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Topical Vitamin C: A Useful Agent for Treating Photoaging and Other Dermatologic Conditions
Abstract
Cosmeceuticals containing antioxidants are among the most popular antiaging remedies. Topically applied antioxidants exert their benefits by offering protection from damaging free radicals produced when skin is exposed to ultraviolet light or allowed to age naturally. Vitamin C is a naturally occurring potent water-soluble antioxidant. Accordingly, it has been incorporated into a variety of cosmeceuticals designed to protect and rejuvenate photoaged skin.
This article reviews the scientific data and clinical studies supporting the use of topically applied vitamin C for treating photoaged skin. Other innovative uses for vitamin C cosmeceuticals are also discussed.
A significant body of scientific research supports the use of cosmeceuticals containing vitamin C. Cutaneous benefits include promoting collagen synthesis, photoprotection from ultraviolet A and B, lightening hyperpigmentation, and improvement of a variety of inflammatory dermatoses. Because of the diverse biologic effects of this compound, topical vitamin C has become a useful part of the dermatologist's armamentarium.
... When used together, these vitamins offer synergistic protection against the harmful effects of UV radiation, reducing the signs of photoaging. Clinical studies indicate that products containing these vitamins reduce the depth of wrinkles and improve skin texture, contributing to skin regeneration (Farris, 2005). ...
... Ingredients such as vitamin C, vitamin E and polyphenols act by neutralizing ROS generated by UV radiation. Clinical trials indicate that combining topical antioxidants with sunscreens improves protection against photoaging and reduces skin inflammation (Farris, 2005). ...
... These products offer convenience and additional benefits, such as hydration and uniform skin tone. Studies indicate that such formulations increase the frequency of use, especially among women, contributing to long-term prevention (Farris, 2005). Sustainability also encompasses the production and packaging of sunscreens. ...
Introduction: Photoprotection is fundamental in preventing signs of skin ageing and in caring for skin health. Chronic exposure to ultraviolet (UV) radiation accelerates premature aging, characterized by wrinkles, loss of elasticity, hyperpigmentation and other cumulative damage to cellular DNA, as well as increasing the risk of developing skin cancer. Objective: To analyze the relevance of photoprotection as an indispensable strategy for preventing the signs of skin aging and maintaining skin health. Methodology: This study used a literature review methodology to investigate the importance of photoprotection in preventing signs of skin ageing and maintaining skin health. Results and Discussion: Broad-spectrum sunscreens (UVA/UVB) play an essential role in preventing photodamage and photoaging. Ultraviolet (UV) radiation is one of the main causes of premature skin ageing and structural damage to the skin. Broad-spectrum sunscreens offer protection against UVB rays, which cause sunburn, and against UVA rays, which are responsible for deeper damage to the dermis. Studies show that regular use of sunscreens reduces the incidence of changes in the extracellular matrix and protects cellular DNA, preventing mutations associated with skin cancer. Conclusion: The regular use of broad-spectrum sunscreens (UVA and UVB), combined with antioxidants and physical barriers, is essential to reduce the harmful effects of the sun. Adopting healthy habits, such as avoiding intense sun exposure and wearing protective clothing, enhances prevention. Strategies combined with dermo-cosmetics help to delay the effects of ageing and preserve the integrity of the skin.
... Vitamin C, for instance, plays a dual role as both an antioxidant and a stimulator of collagen production, making it a popular ingredient in anti-aging formulations. However, antioxidant-based treatments typically require consistent, long-term use to produce visible benefits and may be less effective in more advanced cases of photoaging [55]. ...
... Peptides, such as palmitoyl pentapeptide-4, mimic growth factors that naturally decline with age and help to reinforce the skin's structural integrity. Peptides are generally well-tolerated with minimal side effects, making them suitable for most skin types, including sensitive skin [53,55]. ...
... Antioxidants, although protective, require long-term use for noticeable results, and peptides, while less irritating, may offer more modest improvements compared to other interventions. For optimal results, topical treatments are often combined with other anti-aging therapies, such as laser treatments or chemical peels, to achieve a more comprehensive improvement in skin appearance [54,55]. ...
Background/Aim
Aging involves a progressive deterioration in physiological functions and increased disease susceptibility, impacting all organs and tissues, especially the skin. Skin aging is driven by intrinsic factors (genetics, cellular metabolism) and extrinsic factors (environment, lifestyle). Understanding these mechanisms is vital for promoting healthy aging and mitigating skin aging effects. This review aims to summarize the key factors influencing skin and intrinsic aging, providing a comprehensive understanding of the underlying mechanisms and contributing elements.
Methods
A comprehensive literature review was conducted, focusing on peer‐reviewed journals, clinical studies, and scientific reviews published within the last two decades. The inclusion criteria prioritized studies that addressed intrinsic and extrinsic mechanisms of skin aging. To ensure the relevance and quality of the selected sources, a systematic approach was used to assess study design, sample size, methodology, and the significance of the findings in the context of skin aging.
Findings
The review identifies major internal factors, such as cellular senescence, genetic predisposition, telomere shortening, oxidative stress, hormonal changes, metabolic processes, and immune system decline, as pivotal contributors to intrinsic aging. External factors, including UV radiation, pollution, lifestyle choices (diet, smoking, alcohol consumption, and sleep patterns), and skincare practices, significantly influence extrinsic skin aging. The interplay between these factors accelerates aging processes, leading to various clinical manifestations like wrinkles, loss of skin elasticity, pigmentation changes, and texture alterations.
Conclusion
A comprehensive understanding of both extrinsic and intrinsic factors contributing to skin aging is essential for developing effective prevention and intervention strategies. The insights gained from this review highlight the importance of a multifaceted approach, incorporating lifestyle modifications, advanced skincare routines, and emerging therapeutic technologies, to mitigate the effects of aging and promote healthier, more resilient skin.
... [1] The human body cannot synthesize AA due to the lack of enzyme L-glucono-gamma lactone oxidase hence obtains it through diet. Even when consumed adequately, the amount of AA is too small to have a significant result on the skin, hence topical application becomes the only route to provide vitamin C [2]. L-AA is a water soluble, non-enzymatic antioxidant (which interrupts free radical chain reaction) that can be used alone or in combination with other ingredients in a cosmetic formula. ...
... O HO HO H [2] AA modulates photoaging by donating electrons to neutralize the free radicals that are accumulated in our skin. A more stable ascorbate free radical is formed on the donation of first electron; donation of second electron results in formation of DHA which is non-reactive and can be converted back to AA by the enzyme DHA reductase in presence of glutathione [3]. ...
... The procollagen mRNA which regulates type I and type III collagen synthesis are stabilized and transcription factors are activated by vitamin c thereby imparting anti-aging effect. [2] Vitamin C acts as a depigmenting agent by interrupting the step of melanogenesis by interacting with copper ions present in the active site of tyrosinase enzyme. Tyrosinase enzyme helps in the conversion of tyrosine to melanin [4]. ...
The last two decades have seen an increase in active-led skin care products in over the counter and retail market
places. Consumers have become more knowledgeable about ingredients used in topical products resulting in formulations with
vitamins and other active ingredients gaining popularity. Further, the need for instantaneous and short-term benefits, consumers
are moving towards high doses of active products. This poses a challenge for formulation scientists to stabilize high active doses
and ensure potency over shelf life. Vitamin C or ascorbic acid is one such ubiquitous active commonly found in topical products
claiming brightening, skin firming and toning benefits. As humans lack the enzyme required for synthesis of Vitamin C, we
obtain it through diet or topical application. Vitamin C consumption results in insignificant benefits due to limited bioavailability,
making topical application the major route of delivery. Ascorbic acid is an antioxidant; when applied topically it protects the skin
from damaging free radicals produced due to exposure to UV-rays and other environmental stressors. However, ascorbic acid has
been reported to be unstable in aqueous systems and readily undergoes oxidation making it inactive. This has led to the
generation of multiple pro-drugs and derivatives which dissociate to release free ascorbic acid or its ionic form in the skin. In this
review, we have focused on the clinical efficacy of vitamin C and its derivatives, suitable for various applications. This will serve
as a ready reckoner for formulators creating vitamin C based products.
... L-ascorbic acid is a vital component of collagen biosynthesis, as it acts as the enzymatic cofactor for prolyl hydroxylases, which are essential enzymes for crosslinking and stabilizing the collagen fibers. In a variety of inflammatory dermatoses, the use of L-ascorbic acid is beneficial in enhancing the cohesion in the dermal-epidermal junction [12,13]. In studies to date, this molecule has been shown to be successfully applied in the treatment of hyperpigmentation and melasma. ...
... By affecting the active site of tyrosinase, an enzyme necessary for melanin production, it acts as a skin-lightening agent [14]. It was demonstrated that topically applied L-ascorbic acid reduces post laserresurfacing erythema and decreases acne appearance and acne scarring [13]. Due to its high susceptibility to environmental conditions, the greatest obstacle in utilizing this molecule for incorporation in pharmaceutics, cosmetic products and food is preserving its stability. ...
... Therefore, the future lies in the development of stable and safer new delivery systems, such as microemulsions, emulgels, microcapsules, nanospheres, and liposomes. Additionally, the usage of L-ascorbic acid derivatives such as magnesium ascorbyl phosphate and sodium ascorbyl phosphate (water-soluble derivatives), and ascorbyl-6-palmitate and tetra-isopalmitoyl ascorbic acid (liposoluble derivatives) are increasingly replacing the use of the free L-ascorbic acid form [37]. Studies comparing the stability of the L-ascorbic acid derivatives have demonstrated that of all forms incorporated in solutions or emulsions, magnesium ascorbyl phosphate was the most stable one, followed by ascorbyl-palmitate, whereas the L-ascorbic acid was the least stable [13]. Ascorbyl palmitate, an amphiphilic ascorbic acid derivative, has better stability and ability to penetrate the skin than L-ascorbic acid [38]. ...
The dual controlled release of emulgels makes them efficient drug delivery systems of increasing interest. The framework of this study was to incorporate selected L-ascorbic acid derivatives into emulgels. From the formulated emulgels, the release profiles of actives were evaluated considering their different polarities and concentrations, and consequently their effectiveness on the skin via a long-term in vivo study that lasted for 30 days was determined. Skin effects were assessed by measuring the electrical capacitance of the stratum corneum (EC), trans-epidermal water loss (TEWL), melanin index (MI) and skin pH. In addition, the sensory and textural properties of emulgel formulations were compared with each other. The changes in the rate of the release of the L-ascorbic acid derivatives were monitored using the Franz diffusion cells. The obtained data were statistically significant, and indicated an increase in the degree of hydration of the skin and skin whitening potential, while no significant changes in TEWL and pH values were detected. The consistency, firmness and stickiness of the emulgels were estimated by volunteers applying the established sensory evaluation protocol. In addition, it was revealed that the difference in hydrophilic/lipophilic properties of L-ascorbic acid derivatives influenced their release profiles without changing their textural characteristics. Therefore, this study highlighted emulgels as L-ascorbic acid suitable carrier systems and one of the promising candidates as novel drug delivery systems.
... This occurs upon directly neutralizing ROS through donating it with electrons, inducing collagen synthesis (collagen I and III), and enhancing the activation of lipid-soluble vitamin E (Z. Liu et al. 2018;Farris 2005). This will reduce the membrane-bound α-tocopherol from its oxidized states and ROS-mediated signaling cascades (JNK, NFκB). ...
... Several clinical studies proved such an enhancement of photoaged skin. A 3-month double-blind and randomized study showed that applying 10 percent of vitamin C improves the patients' skin wrinkles, tiredness, and hyperpigmentation brightness compared to control (Farris 2005). Also, vitamin C can prevent ROS-induced inflammation by suppressing transcription factor NFκB, thereby inhibiting the production of proinflammatory cytokines (TNF, Interleukin-1/6/8) (Z. ...
... Also, vitamin C can prevent ROS-induced inflammation by suppressing transcription factor NFκB, thereby inhibiting the production of proinflammatory cytokines (TNF, Interleukin-1/6/8) (Z. Liu et al. 2018;Farris 2005). ...
Xeroderma pigmentosum C (XPC) protein initiates global genome-nucleotide excision repair (GG-NER) to remove UV-induced helix-distorting DNA lesions such as pyrimidine (6-4) pyrimidone photoproducts [(6-4) PPs] and cyclobutane pyrimidine dimers (CPDs). XPC deficient (XP-C) patients show a persistence of such lesions triggering high skin cancer incidences. They also suffer from internal cancers that could be due to the accumulation of oxidative DNA damage. Such oxidative DNA damage, including 8-oxoguanine (8-oxoGua), is usually repaired by the base excision repair (BER) pathway. Despite growing evidence about how XPC enhances the activity of several BER DNA glycosylases, the effect of XPC mutations on other BER factors and their activities is still elusive. Herein, we seek to answer this open question by characterizing normal and XP-C fibroblasts derived from patients, optimizing the conditions, and dividing our project into two parts.In part one, we showed a global downregulation of BER’s genes in XP-C cells post-UVB compared to normal ones. Furthermore, the major proteins linked to oxidative DNA damage repair (OGG1, MYH, and APE1) were downregulated. This led to an ineffectiveness of BER in excising UVB-induced oxidized purines. In part two, we investigated whether treating XP-C cells with different drugs balancing the redox state could boost BER’s activity in XP-C cells. We showed that nicotinamide (NIC) and N-acetyl cysteine (NAC) pretreatments increase glutathione level, decrease ROS level, and enhance BER’s gene expression and activity post-UVB. Meanwhile, buthionine sulfoximine/dimethylfumuate (BSO/DMF) pretreatment depletes glutathione level, increases ROS level, and impairs BER’s gene expression and activity post-UVB.Based on these results, we could propose that pretreatment with drugs that could enhance glutathione’s level may protect XP-C cells from an imbalanced redox state that affects DNA repair. This could pave the way for therapeutic strategies for XP-patients and other DNA repair-deficient patients.Future work is required to check the efficiency of such treatments on 3D reconstructed skin and in vivo models. Additionally, studying the interactome linking XPC and glutathione signaling could be interesting.Keywords: Ultraviolet irradiation-B (UVB), xeroderma pigmentosum C (XPC), nucleotide excision repair (NER), bulky lesions (CPDs and (6-4) PPs), base excision repair (BER), oxidative DNA lesions (8-oxoguanine), oxidative stress, glutathione (GSH), nicotinamide (NIC), N-acetylcysteine (NAC), buthionine sulfoximine/dimethyl fumarate (BSO/DMF)
... L-ascorbic acid (AA; vitamin C), a well-known water-soluble vitamin, has extremely low passive permeability owing to its intrinsic hydrophilicity (log K ow = −2.13) and the characteristics of the stratum corneum (SC) of the skin [20,21]. Various strategies to facilitate skin penetration of AA have been studied, such as encapsulation of AA in soluble microneedles [22] or hydrogels [23] or the use of iontophoresis techniques [24]. ...
... L-ascorbic acid (AA; vitamin C), a well-known water-soluble vitamin, has extremely low passive permeability owing to its intrinsic hydrophilicity (log Kow = −2.13) and the characteristics of the stratum corneum (SC) of the skin [20,21]. Various strategies to facilitate skin penetration of AA have been studied, such as encapsulation of AA in soluble microneedles [22] or hydrogels [23] or the use of iontophoresis techniques [24]. ...
L-ascorbic acid (AA), a potent antioxidant, is commonly used topically in the pharmaceutical and cosmetic fields. However, the incorporation of AA into topical formulations is difficult because of its highly unstable nature and relatively poor skin permeability. In this study, we propose an alternative strategy for improving the solubility and topical delivery of AA through its conversion to a therapeutic deep eutectic system (THEDES). AA and betaine (Bet)-based THEDESs were prepared at certain molar ratios and characterized using polarized optical microscopy, Fourier transform infrared spectroscopy, and differential scanning calorimetry. Solubility tests showed that AA in the form of THEDES was readily soluble in various polyols (glycerin, 1,3-butylene glycol, dipropylene glycol, and 1,3-propanediol) at a high concentration (approximately 40%). Furthermore, compared to AA alone or the physical mixture of AA and Bet, AA-based THEDES significantly enhanced AA delivery through porcine skin. In an in vivo human study, THEDES-containing serum reduced the markers of aging and induced an even skin tone. These findings indicate the utility of AA and Bet-based THEDES as novel transdermal delivery systems for AA. Furthermore, our approach also showed good extension to developing gluconolactone, a well-known natural antioxidant, and Bet-based THEDES, showing potential application in transdermal delivery systems.
... Food containing vitamin C consists of citrus culmination, kiwifruit, broccoli, Brussel sprouts, uncooked bell peppers, and strawberries. Besides being an antioxidant, vitamin C has different skin aids such as enhancing collagen formation and blurring dark spots [42,45,57]. ...
... Tulsi oil is acquired by way of distillation of sparkling and dried leaves of Ocimum sanctum from the family Labiatae. It contains approximately 70% eugenol, eugenol methyl ether, and also contains considerable amounts of Vitamin C. It has antibacterial properties and eliminates bad breath and, additionally, has enamel cleaning activities [42,57]. ...
Abstract: Cosmetic-containing herbals are a cosmetic that has or is claimed to have medicinal properties, with bioactive ingredients purported to have medical benefits. There are no legal requirements
to prove that these products live up to their claims. The name is a combination of “cosmetics” and “pharmaceuticals”. “Nutricosmetics” are related dietary supplements or food or beverage products with additives that are marketed as having medical benefits that affect appearance. Cosmetic-containing herbals are topical cosmetic–pharmaceutical hybrids intended to enhance the health and beauty of the skin. Cosmetic-containing herbals improve appearance by delivering essential
nutrients to the skin. Several herbal products, such as cosmetic-containing herbals, are available. The present review highlights the use of natural products in cosmetic-containing herbals, as
natural products have many curative effects as well as healing effects on skin and hair growth with minimal to no side effects. A brief description is given on such plants, their used parts, active ingredients,
and the therapeutic properties associated with them. Mainly, the utilization of phytoconstituents as cosmetic-containing herbals in the care of skin and hair, such as dryness of skin, acne, eczema,
inflammation of the skin, aging, hair growth, and dandruff, along with natural ingredients, such as for hair colorant, are explained in detail in the present review.
Keywords: cosmetic-containing herbals; bioactive ingredients; cosmetics
... Food containing vitamin C consists of citrus culmination, kiwifruit, broccoli, Brussel sprouts, uncooked bell peppers, and strawberries. Besides being an antioxidant, vitamin C has different skin aids such as enhancing collagen formation and blurring dark spots [42,45,57]. ...
... Tulsi oil is acquired by way of distillation of sparkling and dried leaves of Ocimum sanctum from the family Labiatae. It contains approximately 70% eugenol, eugenol methyl ether, and also contains considerable amounts of Vitamin C. It has antibacterial properties and eliminates bad breath and, additionally, has enamel cleaning activities [42,57]. ...
Cosmetic containing herbals,a cosmetic that has or is claimed to have medicinal properties. Cosmetic-containing herbals are cosmetic products with bioactive ingre-dients purported to have medical benefits. There are no legal requirements to prove that these products live up to their claims. The name is a combination of "cosmetics" and "pharmaceuticals". "Nutricosmetics" are related dietary supplements or food or beverage products with additives that are marketed as having medical benefits that affect appearance. Cosmetic-containing herbals are topical cosmetic- pharmaceuti-cal hybrids intended to enhance the health and beauty of the skin. Cosmet-ic-containing herbals improve appearance by delivering essential nutrients to the skin. Several herbal products as cosmetics containing herbals are available. The pre-sent review highlighted the use of natural products in cosmetics containing herbals, as natural products have manycurative effects as well as healing effects on skin and hair growth, with minimum or no side effects on the same.A brief description has been given here about plants, their part used, active ingredients, and the therapeutic properties associated with the same. Mainly, the utilization of phytoconstituents as cosmetic containing herbals, in the care of skin and hair, like dryness of skin, acne, eczema, inflammation of the skin, aging, hair growth, dandruff, along with natural ingredients as hair colorant has been well explained in the present review.
... These are highly susceptible for carrying out any oxidation reactions. Harmful effects of oxidative reaction includes disordered deoxyribonucleic acid (DNA), impaired cell membranes, proteins, and collagen in elderly skin [6]. Certain antioxidants have been reported that counter these harmful effects of ROS. ...
... Vitamin C, specifically in its L-ascorbic acid form, is a potent antioxidant known for its ability to mitigate oxidative stress and inhibit melanin production by blocking the tyrosinase enzyme [52,53]. However, the poor stability of L-ascorbic acid compromises its penetration into the skin and diminishes its efficacy. ...
Facial hyperpigmentation is a highly prevalent dermatological condition, characterized by dark spots on the skin resulting from excess melanin production. Hyperpigmentation significantly impacts patients’ quality of life and self-esteem. Current treatments often present disadvantages linked to poor product tolerability. A topical cosmetic approach combining three lightening active ingredients (tranexamic acid, niacinamide, vitamin C) offers a new option for treating dark spots on the skin. The present in-use test under dermatological control evaluated the clinical safety and efficacy of a cream and serum containing these three ingredients, formulated with hyaluronic acid for enhanced delivery, stability, and efficacy. A total of 22 Caucasian patients with facial hyperpigmentation, both male and female, aged between 45 and 67 years, applied the cream and serum for 8 weeks. Clinical assessments, colorimetric evaluations, standardized photography, and self-assessment questionnaires were used to measure outcomes. No serious adverse effects were recorded, and the incidence of local adverse effects was low, highlighting good tolerability of the investigated test items. In most participants, significant improvements in hyperpigmented areas were recorded. Clinical scoring by the dermatologist investigator indicated a statistically significant 13% reduction in color intensity and a 6% reduction in the size of dark spots after 8 weeks of treatment. Colorimetric evaluation showed a statistically significant 1% increase in luminosity (L* parameter) and an 8% improvement in the Individual Typological Angle (ITA°) in endpoint, indicating lighter skin spots. Subjective assessments reflected high user satisfaction, with 95% of participants noting improvements in skin hydration and luminosity, and 77% reporting a reduced appearance of dark spots. Overall, the present work supports the use of tranexamic acid, niacinamide, and vitamin C as an effective and well-tolerated combined topical management option for hyperpigmentation. This combination offers a viable alternative to classical whiteners for individuals seeking to reduce facial skin coloration imbalance and improve skin tone.
... Lifestyle modifications play a pivotal role in preventing premature skin aging by addressing both intrinsic and extrinsic factors. 60,61 Dietary habits, for instance, significantly impact skin health, with the formation of advanced glycation end-products (AGEs) from high sugar intake being linked to skin aging through the stiffening of collagen fibers and loss of skin elasticity. 60 Additionally, environmental factors, such as exposure to pollutants, have been identified as major contributors to atmospheric skin aging, exacerbating oxidative stress and accelerating the aging process. ...
Introduction and Aim. Premature skin aging results from both intrinsic and extrinsic factors, requiring a comprehensive management strategy. This review evaluates current and emerging approaches for preventing and treating premature skin aging, focusing on efficacy and safety.Materials and Methods. A review of recent scientific literature on topical, oral, and procedural interventions for managing premature skin aging was conducted.Analysis of Literature. Topical treatments, particularly retinoids and antioxidants, are key in skin regeneration and oxidative stress reduction. Oral interventions, including systemic retinoids and nutraceuticals, support overall skin health. Procedural methods like laser therapies, microneedling, and chemical peels are effective in skin rejuvenation. Preventive measures, such as photoprotection and lifestyle changes, are crucial. Emerging therapies, such as stem cell treatments, show promise in reversing age-related skin changes.Conclusion. Managing premature skin aging requires a combination of topical, oral, and procedural treatments with preventive strategies. Future research should focus on refining protocols, assessing novel therapies' long-term safety, and developing personalized approaches considering genetic, environmental, and lifestyle factors.
... Despite its numerous benefits, several limitations and challenges are associated with the use of Vitamin C in cosmetics. Vitamin C, particularly L-ascorbic acid, is very unstable and can easily oxidize when exposed to air, light, and heat, reducing its effectiveness and potentially causing the product to yellow or brown [6,7]. Stabilizing Vitamin C requires careful attention to pH, as it is more stable at a pH below 3.5, but maintaining this low pH can be difficult and may not be suitable for all skin types, especially sensitive skin [8]. 2 Effective concentrations of Vitamin C in skincare products typically range from 5% to 20%. ...
Introduction: This study explores the stabilization and efficacy enhancement of Vitamin C in dermocosmetic formulations through its association with Poly-L-lysine dendrimers. Vitamin C, critical for collagen synthesis and skin hydration, faces challenges due to its instability and low bioavailability. The research aims to evaluate the liposolubility of Vitamin C in the presence of Poly-L-lysine vectors, assess its stability in both aqueous and emulsion media, and determine the moisturizing efficacy of second-generation Poly-L-lysine (diameter: 4.5 nm, PM: 8.6 kDa) and third-generation Poly-L-lysine (diameter: 7 nm, PM: 22 kDa). Methods : Methods included high-performance liquid chromatography (HPLC) for concentration analysis, partition coefficient determination, and stability assessments under various conditions. Hydration potential and kinetics were evaluated on 11 volunteers using a corneometer. Results: The liposolubility of Vitamin C increased by over 300% with Poly-L-lysine, enhancing its stability. Emulsion stability tests confirmed that formulations with Poly-L-lysine maintained their physical and chemical properties under stress conditions. Physiological tests showed significant improvements in skin hydration with the Poly-L-lysine/Vitamin C formulations, achieving 66.2% hydration increase at T3h for third-generation dendrimers. Conclusion In conclusion, Poly-L-lysine vectors significantly enhance the stability and moisturizing efficacy of Vitamin C in dermocosmetic formulations. These findings suggest that Poly-L-lysine can mitigate Vitamin C's instability and improve its dermocosmetic benefits, offering a promising approach for advanced skincare solutions.
... Research on the mechanism of skin photoaging has demonstrated that ascorbic acid, an antioxidant, donates two electrons and scavenges ROS [4]. It protects the skin by promoting collagen synthesis; suppressing MMP-1, a collagen-degrading enzyme; and providing photoprotection against ultraviolet rays and inflammation [5]. Organically synthesized vitamin derivatives are primarily available commercially; however, they have an unstable molecular structure. ...
Allomyrina dichotoma larvae (ADL) is an insect type that is used ethnopharmacologically to treat various diseases; however, its use as an antiaging treatment has not been widely studied. Previously, we found that an ethyl acetate (EA) fraction derived from an ADL extract (ADLE) has a high polyphenol content and antioxidant properties. In this study, we identified the underlying molecular mechanism for the protective effect of the EA fraction against UVB-induced photodamage in vitro and ex vivo. UVB treatment increased intracellular reactive oxygen species levels and DNA damage; the latter of which was significantly decreased following cotreatment with the EA fraction. Biological markers of aging, such as p16INK4a, p21WAF1, and senescence-associated β-gal levels, were induced by UVB treatment but significantly suppressed following EA-fraction treatment. UVB-induced upregulation of matrix metalloproteinase (MMP)-1 and downregulation of COL1A1 were also reversed by EA-fraction treatment in both cells and a 3D skin model, which resulted in increased keratin and collagen deposition. Moreover, EA-fraction treatment inhibited the phosphorylation of MAPKs (p38, ERK, and JNK) and nuclear factor (NF-)-kB and decreased the levels of inflammatory cytokines in UVB-treated cells. The results indicate that an EA fraction from ADLE ameliorates UVB-induced degradation of COL1A1 by inhibiting MMP expression and inactivating the MAPK/NF-κB p65/AP-1 signaling pathway involved in this process.
... Additionally, it inhibits the tyrosinase enzyme responsible for hyperpigmentation collagen synthesis and processing [41]. However, the extensive list of prophylactic or therapeutic antioxidant agents in dermocosmetics includes both synthetic and naturally obtained bioactives [42]. ...
The quest for youthful, healthy skin and full, vibrant hair has long been a driving force in the dermocosmetics field. However, traditional approaches often struggle to address the underlying causes of aging, damage, and hair loss. Regenerative cosmetics powered by skin tissue engineering offer a transformative alternative. This review explores the emerging field of using engineered skin tissues for cosmetic purposes, focusing specifically on their potential for anti-aging, repair, and hair restoration applications. We discuss how these technologies aim to rejuvenate aging skin by promoting collagen production, reducing wrinkles, and improving overall skin function. Additionally, the use of engineered skin for wound healing and scar reduction is examined, highlighting their potential to improve the appearance and functionality of damaged skin. Finally, we advance the exciting prospects of utilizing skin tissue engineering techniques to regenerate hair follicles, potentially offering solutions for hair loss and promoting denser hair growth.
... In its natural form or modified in more stable derivatives, ascorbic acid acts as a potent hydrosoluble electron donor, neutralizing free radicals [36]. In cosmetology, this molecule possesses additional several relevant properties such as regenerating α-tocopherol to protect against lipid peroxidation, reversing hyperpigmentation by inhibiting the tyrosinase enzyme [38] and enhancing collagen synthesis and processing {Nusgens, 2001 #106]. However, the list of prophylactic or therapeutic antioxidant agents in dermocosmetics is extensive and includes other synthetic and naturally-obtained bioactives [39]. ...
The quest for youthful, healthy skin and full, vibrant hair has long been a driving force in the dermocosmetics field. However, traditional approaches often struggle to address the underlying causes of aging, damage, and hair loss. Regenerative cosmetics, powered by skin tissue engineering, offer a transformative alternative. This review explores the emerging field of using engineered skin tissues for cosmetic purposes, focusing specifically on their potential for anti-aging, repair, and hair restoration applications. We discuss how these technologies aim to rejuvenate aging skin by promoting collagen production, reducing wrinkles, and improving overall skin function. Additionally, the use of engineered skin for wound healing and scar reduction is examined, highlighting their potential to improve the appearance and functionality of damaged skin. Finally, we advance the exciting prospects of utilizing skin tissue engineering techniques to regenerate hair follicles, potentially offering solutions for hair loss and promoting denser hair growth.
... The rationale behind our choice of CE Ferulic © serum lies in its formulation, which integrates potent depigmenting agents, including 15% L-Ascorbic Acid (Vitamin C), 1% α-tocopherol (Vitamin E), and 0.5% Ferulic Acid. These constituents have been widely recognized for their antioxidative and skin-rejuvenating properties, making them ideal candidates for synergistic integration with microneedling therapy [43][44][45][46][47]. ...
Pigmentary disorders of the face present a significant challenge in dermatology, impacting the confidence and well-being of affected individuals. Various approaches have been developed to address these concerns, including microneedling and topical vitamin C products. This study involved 15 participants undergoing three treatment sessions over 12 weeks, assessing the efficacy of a combined microneedling and CE Ferulic© serum approach. Clinical evaluation and statistical analysis were conducted before and after the intervention. Significant improvement of akin hyperpigmentation was observed, particularly on the side treated with microneedling and CE Ferulic© serum compared to microneedling alone. The integrated treatment protocol demonstrated a synergistic effect in improving skin texture and appearance. Integrated treatment protocols, such as combining microneedling with CE Ferulic© serum, show promise in managing facial hyperpigmentation disorders. Further research with larger cohorts is warranted to validate these findings and optimize treatment strategies, highlighting the potential of combined therapeutic modalities for achieving optimal clinical outcomes in pigmentary disorder management.
... They help diminish the appearance of fine lines, improve skin hydration, and enhance the skin's natural defence against UV-induced damage. 14,15 2.1.2 Niacinamide: Vitamin B3, also known as niacinamide, enhances the skin barrier, reduces hyperpigmentation, and improves skin texture. ...
Cosmeceuticals represent an innovative product category positioned between cosmetics and pharmaceuticals, aimed at improving both skin health and its aesthetic qualities. As an ever-growing sector within the skincare industry, cosmeceuticals are crafted using a wide range of ingredients, which we will delve into in this article by categorizing them into primary groups. Given the increasing interest among consumers in these products and the strong marketing claims made by manufacturers, physicians must become acquainted with these agents, and comprehend their benefits, limitations, and potential adverse effects.
... They help diminish the appearance of fine lines, improve skin hydration, and enhance the skin's natural defence against UV-induced damage. 14,15 2.1.2 Niacinamide: Vitamin B3, also known as niacinamide, enhances the skin barrier, reduces hyperpigmentation, and improves skin texture. ...
Cosmeceuticals represent an innovative product category positioned between cosmetics and pharmaceuticals, aimed at improving both skin health and its aesthetic qualities. As an ever growing sector within the skincare industry, cosmeceuticals are crafted using a wide range of ingredients, which we will delve into in this article by categorizing them into primary groups. Given the increasing interest among consumers in these products and the strong marketing claims made by manufacturers, physicians must become acquainted with these agents, and comprehend their benefits, limitations, and potential adverse effects.
... By targeting underlying skin issues and stimulating cellular processes, cosmeceuticals aim to deliver noticeable and lasting results [8]. The incorporation of active ingredients in cosmeceuticals is supported by scientific research and studies [7]. These studies demonstrate the efficacy and potential benefits of specific ingredients in improving various skin conditions and promoting skin wellness. ...
Cosmeceuticals, a fusion of cosmetics and pharmaceuticals, have emerged as powerful tools in addressing a myriad of skin concerns, ranging from combating signs of aging to managing acne. These advanced skincare products are distinguished by their enriched formulations, featuring active ingredients that go beyond traditional cosmetic offerings. The key to unlocking their full potential lies in a nuanced understanding of individual skin types and specific needs. One of the primary advantages of cosmeceuticals is their ability to deliver tailored solutions for diverse skincare issues. Whether someone is seeking to diminish fine lines and wrinkles, control acne breakouts, or address hyperpigmentation, these products are designed to provide targeted benefits. The incorporation of potent ingredients, such as retinoids, hyaluronic acid, and antioxidants, allows for a more sophisticated and effective approach to skincare. To harness the maximum benefits of cosmeceuticals, it is crucial to comprehend the unique characteristics of one's skin. Different skin types, whether oily, dry, sensitive, or combination, necessitate specific formulations to achieve optimal results. Tailoring the skincare routine to individual needs ensures that active ingredients address concerns without causing unnecessary irritation or imbalance. Moreover, the synergy between cosmeceuticals and professional cosmetic treatments can elevate skincare outcomes. Combining the benefits of at-home products with in-office procedures, such as chemical peels or laser treatments, can enhance and prolong the effectiveness of the overall skincare regimen. Professional guidance becomes invaluable in navigating the intricate landscape of cosmeceuticals, helping individuals customize their routines for optimal results. However, the transformative potential of cosmeceuticals comes with a responsibility for cautious application. Ingredient compatibility is a critical consideration to avoid adverse reactions and maximize efficacy.
... In this regard, vitamin C is one of the main antioxidants present in various nutritional supplements and fruits, such as orange and lemon. Vitamin C counteracts lipid peroxidation, reduces ROS-induced damage, inhibits NfκB activation, stimulates collagen production by enhancing its genetic expression, and acts as a collagen-stabilizing molecule structure because of its action on lysine and proline hydroxylases [78][79][80]. Furthermore, a study on 33 patients using electron paramagnetic resonance spectroscopy showed that vitamin C supplementation at doses of 100 mg/d and 180 mg/d for 4 weeks caused an increase in ROS elimination by 22% and 37%, respectively [81]. ...
Photoaging (PA) is considered a silent disease affecting millions of people globally and is defined as skin damage due to prolonged exposure to ultraviolet radiation (UVR) from the sun. Physiologically, the skin is in a state of renewal and synthesis of components of the extracellular matrix (ECM). However, exposure to UVR affects the production of the ECM, and the functioning and response of skin cells to UVR begins to change, thus expressing clinical and phenotypic characteristics of PA. The primary mechanisms involved in PA are direct damage to the DNA of skin cells, increases in oxidative stress, the activation of cell signaling pathways responsible for the loss of skin integrity, and cytotoxicity. The medical and scientific community has been researching new therapeutic tools that counteract PA, considering that the damage caused by UVR exceeds the antioxidant defense mechanisms of the skin. Thus, in recent years, certain nutraceuticals and phytochemicals have been found to exhibit potential antioxidant and photoprotective effects. Therefore, the main objective of this review is to elucidate the molecular bases of PA and the latest pharmaceutical industry findings on antioxidant treatment against the progression of PA.
... Overall, the results demonstrated the superiority of adding PRP to microneedling. However, Farris [17] demonstrated that vitamin C, when applied topically, stimulates the collagen production of the skin dermis, leading to the improvement in skin photoaging. As well, Nada et al. [18] made a cross-sectional clinical study on 10 patients with acne scars who were treated with six microneedling sessions plus topical vitamin C with 4-week intervals. ...
Background and aim
Postacne scars may affect about 95% of patients with past history of acne that is related to its duration and severity of. Treatment of acne scarring is challenging. Microneedling with platelet-rich plasma (PRP) or vitamin C is a new, simple, and effective treatment modality for such scars. The authors aimed to compare between microneedling plus PRP versus microneedling plus vitamin C in treatment of postacne scars.
Patients and methods
This is a comparative study that was carried out on 20 patients (their ages ranged from 22 to 37 years). They are four males and 16 females, they presented with postacne scars. The patients were divided randomly to receive microneedling plus PRP on one side of the face, and microneedling plus vitamin C on the other side.
Results
The authors found a significant improvement of atrophic acne scars, with significant reduction in the number of acne scars as well as Goodman score after treatment by microneedling plus PRP as well as microneedling plus vitamin C, moreover, most of the patients were satisfied after treatment with no significant difference between both treatment methods. Microneedling with PRP and vitamin C was well-tolerated with no major adverse events that were observed.
Conclusion
PRP as well as vitamin C combined with microneedling is a safe, effective, and promising option in treatment of acne scars.
... Vitamin C interrupts copper ions, inhibiting the tyrosinase pathway, and thereby decreasing melanin synthesis. In addition, it also plays a role in collagen synthesis and serves as an antioxidant, making it a multifactorial treatment option to target photodamage along with pigmentation [19]. It is currently used for many applications within dermatology, as both a single-agent option and an adjunct to other treatment modalities, such as chemical peels [20]. ...
Hyperpigmentation disorders greatly impact the quality of life of many patients. Vitamin C and ascorbic acid derivatives are commonly used as topical agents to reduce the effect of facial dyschromia. The market for vitamin C topicals has greatly increased, but with little oversight, resulting in a wide variety of products with regard to purity and efficacy. In this study, we conducted an analysis of the most highly rated vitamin C-containing compounds on Amazon and Sephora. It was found that consumers for both retailers prioritized efficacy and cosmetic elegance in their rating of products. Additionally, consumers displayed no preference among vitamin C derivatives in the products available to them. This study highlights the diverse vitamin C formulations currently available as well as consumer preferences, emphasizing the importance of fully reviewing all products patients are utilizing to better counsel on treatment regimens.
... 14 Vitamin C is a potent antioxidant and topical vitamin C has been shown to be a useful agent for the treatment of photoaging and other dermatological conditions. 15 Vitamin C derivatives are used in various skin-care products for skin lightening and protection against ultraviolet A/B light. Dermatix (Registered trademark, Menarini, Singapore) Ultra and Dermatix Ultra Kids are silicone gels that contain vitamin C ester. ...
Preventing abnormal scar formation and correcting non-aesthetic mature scars are important to prevent physical and psychosocial consequences of abnormal scarring. Evidence-based guidelines for scar management in Asian patients recommend first-line silicone-based products. Dermatix® Ultra and Dermatix Ultra Kids are topical silicone gels containing a vitamin C ester that helps lighten scar tissue. Herein, we report a case series including patients with hypertrophic and keloid scars treated with Dermatix, showing that Dermatix is effective for scar treatment and prevention, as well as expert consensus supporting the safe and effective use of Dermatix.
... It is also necessary for the proper functioning of the body, so its content in animal feed as well as in diet supplements is highly recommended. Thanks to its antioxidant potential, it can be used topically in dermatology to treat and prevent changes associated with photoaging [58]. Citrus fruit juice is one of the best sources of vitamin C. ...
Kaffir lime (Citrus hystrix) is a popular citrus in Southeast Asia. Despite the growing interest in the peel of the fruit, the leaves are the most frequently used part of the fruit. The aim of the study was to determine the main by-products of the peel, such as pectins, minerals, essential oil, and bioactive compounds, and to evaluate the possibility of using them in various branches of industry. In the study of the essential oil obtained by hydrodistillation performed using the TGA chromatography technique (GC-MS), sabinene (31.93%), β-pinene (26%), and limonene (19%) were selected as the most abundant volatile compounds. Nine microelements (Fe, Zn, Cu, Mn, Co, Ni, Cr, Mo, and V), four macroelements (Mg, Ca, K, and Na), and seven ballast substances (Cd, Hg, Pb, Al, V, Sr, and Pt) were also determined using the microwave plasma-atomic emission spectrometry technique (MP-AES). In the case of microelements, iron 32.72 ± 0.39 mg/kg DW (dry weight) had the highest concentration. In the case of macroelements, the calcium content was 9416 ± 34 mg/kg DW. Optimization of the pectin extraction was also performed by selecting citric acid and obtaining a yield of 7.6–17.6% for acid extraction and 9.9–28.2% for ultrasound-assisted extraction (UAE), depending on the temperature used. The obtained pectins were characterized by the degree of methylation, galacturonic acid content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, and DSC (differential scanning calorimetry) analysis. Among bioactive compounds, the contents of polyphenols (22.63 ± 2.12 mg GAE/g DW), flavonoids (2.72 ± 0.25 mg CE/g DW, vitamin C (2.43 ± 0.19 mg Asc), xantoproteins + carotenes (53.8 ± 4.24 ug), anthocyanins (24.8 ± 1.8 mg CGE/kg DW), and chlorophylls A and B (188.5 ± 8.1, 60.4 ± 3.23 µg/g DW) were evaluated. Antioxidant capacity using (cupric ion-reducing antioxidant capacity) CUPRAC and DPPH assays was also provided with the results of 76.98 ± 8.1, and 12.01 ± 1.02 µmol TE/g DW, respectively.
... Different strategies have been tested to solve the problem of the stability of vitamin C, such as encapsulation, formulation at low pH, oxygen-tight packaging, and the addition of electrolytes and other antioxidants [25]. ...
The topical use of vitamin C as a cosmetic arouses much interest within the field of medicine and cosmetic dermatology. Its different forms of presentation have evolved over the years to increase its bioavailability. Its use in cosmetics generates significant amounts of money day after day. Is there scientific evidence of its usefulness and its absorption? Is there scientific support for the marketing campaigns on the cosmetic use of Vitamin C? Does it present any contraindication or can it be used universally? What is new in the topical use of Vitamin C? Are all cosmetic presentations effective? Is it as useful as the cosmetic industry tells us?
... Ascorbic acid is known to enhance collagen synthesis (99,100) and wound healing (101), reduce UV-induced damage (102,103), and exhibit anti-inflammatory effects (104,105); however, these effects are primarily skin-confined. Recently, the CAF cancer microenvironment has attracted considerable attention (10,11), although few studies have described the effects of ascorbic acid on CAFs. ...
Ascorbic acid has attracted substantial attention for its potential antitumor effects by acting as an antioxidant in vivo and as a cofactor in diverse enzymatic reactions. However, solid proof of its clinical efficacy against cancer and the mechanism behind its effect have not been established. Moreover, cancer forms cancer-specific microenvironments and interacts with various cells, such as cancer-associated fibroblasts (CAFs), to maintain cancer growth and progression; however, the effect of ascorbic acid on the cancer microenvironment is unclear. This review discusses the effects and mechanisms of ascorbic acid on cancer, including the role of ascorbic acid concentration. In addition, we present future perspectives on the effects of ascorbic acid on cancer cells and the CAF microenvironment. Ascorbic acid has a variety of effects, which contributes to the complexity of these effects. Oral administration of ascorbic acid results in low blood concentrations (<0.2 mM) and acts as a cofactor for antioxidant effects, collagen secretion, and HIFα degradation. In contrast, intravenous treatment achieves large blood concentrations (>1 mM) and has oxidative-promoting actions that exert anticancer effects via reactive oxygen species. Therefore, intravenous administration at high concentrations is required to achieve the desired effects on cancer cells during treatment. Partial data on the effect of ascorbic acid on fibroblasts indicate that it may also modulate collagen secretion in CAFs and impart tumor-suppressive effects. Thus, future studies should verify the effect of ascorbic acid on CAFs. The findings of this review can be used to guide further research and clinical trials.
... Vitamin C is known to be involved: (1) in collagen formation by acting as a co-factor for the proline and lysine hydroxylases; (2) as a potent antioxidant as a scavenger of free radicals; (3) in the inhibition of melanogenesis; and (4) in the differentiation or proliferation of skin component cells such as keratinocytes and fibroblasts [37]. Evidence about the variability and roles of vitamin C in intrinsic skin aging and extrinsic skin aging induced by ultraviolet radiation is still emerging [38]. For that reason, topical application of vitamin C in a cosmetic formulation has been proposed as an effective approach for protecting against intrinsic or UV-induced photoaging, while transdermal delivery of vitamin C has been challenging due to numerous factors. ...
Microneedles have emerged as a novel transdermal delivery tool that enables the delivery of various products such as drugs, vaccines, or cosmetic ingredients. Although the demand for solid microneedles composed of biocompatible polymer is increasing, the manufacture of microneedles using poly-lactic acid (PLA) with rapid drug-releasing is yet to be established and the process is still in its infancy. Here, we propose a novel strategy for the fabrication of PLA solid microneedles which enable a drug to be burst-released based on a solvent-casting process. This approach offers extreme simplicity, broad geometric capability, cost-effectiveness, and scalability based on high fidelity-replicas. It was verified that microneedles of various heights (250–500 μm) could be fabricated with appropriate mechanical strength to penetrate the stratum corneum layer of skin. By adding sugar in the composition of PLA microneedle, it was observed that both hydrophilic and hydrophobic drugs can be rapidly released within 30 min. Our burst drug-releasing PLA microneedle having both characteristics of solid microneedle and soluble microneedle and its fabrication approach based on solvent-casting will contribute to getting microneedle technology close to commercialization and beyond existing technical limitations.
... Antioxidants such as AA play an important role in preventing signs of photoaging and hyperpigmentation [11][12][13]. Unlike chronological aging, which is predetermined by an individual's physiological predisposition, photoaging depends primarily on the degree of sun exposure and the amount of melanin in the skin. Clinical signs of photoaging include wrinkles, mottled pigmentation (hypo-or hyperpigmentation), rough skin, loss of skin tone, dryness, sallowness, deep furrows, severe atrophy, telangiectasias, laxity, leathery appearance, solar elastosis, actinic purpura, precancerous lesions, skin cancer, and melanoma [14,15]. ...
Vitamin C is one of the naturally occurring antioxidants capable of reducing or preventing skin photoaging. Achieving a stable formulation with the optimal dose of ascorbic acid to ensure a biologically significant antioxidant effect is a challenge when developing cosmetic formulations. The objective of this study was to develop a stable formula in a non-aqueous media with 15% pure vitamin C supplemented with ginger and to study its efficacy, skin tolerance, and cosmetic assessment in 33 women. Vitamin C stability over time was determined via a high-performance liquid chromatography (HPLC) technique versus an aqueous option. Reactive oxygen species (ROS) determination was quantified to provide antioxidant effect. A 56-day in vivo study was performed to evaluate skin luminosity and hyperpigmentation reduction. Skin acceptability was verified by a dermatologist. The HPLC studies demonstrated a high stability of the anhydrous formula compared to an aqueous option. The in vitro studies showed a reduction in ROS of 93% (p-value < 0.0001). In vivo, luminosity increased by 17% (p-value < 0.0001) and skin tone became 10% more uniform (p-value < 0.007). Moreover, very good skin tolerance was determined as the dermatologist did not determine any clinical signs, and the subjects did not report any feelings of discomfort. We were able to develop an anhydrous formula of pure vitamin C that combines very good stability, consumer acceptance, and skin tolerance with a high level of efficacy.
... Indeed, some are not cleaved by the skin to the active antioxidants, ascorbic acid or αtocopherol; thus, they have lower activity [19,21]. Ester or ether derivatives of AA, for example magnesium-L-ascorbyl-2-phosphate, 3-O-ethyl-l-ascorbic acid, have been used to stabilize AA and are reported to be enzymatically converted to AA within the skin [22][23][24][25][26]. Although in vivo and in vitro studies demonstrated antioxidants effects of this type of prodrugs after enzymatic cleavage, this does not always lead to an increase levels of AA in the skin, for example magnesium ascorbyl phosphate, ascorbyl-6-palmitate and dehydroascorbic acid [19]. ...
Objective:
Deleterious effects of pollutants and ultraviolet radiation on the skin can be attenuated using formulations containing antioxidants. However, these have disadvantages, including chemical instability, photodegradation, poor bioavailability or biological activity. Here, two commercial formulations were evaluated: one optimized to stabilize and deliver ascorbic acid (AA) at 15% and the other containing a glucoside form of AA, namely ascorbic acid 2-glucoside (AA2G), at 1.8% and at a physiological pH. We compared the skin delivery, antioxidative effects and chemical stability of AA2G with AA in their respective formulations.
Methods:
Skin delivery was measured using fresh viable human skin explants, and oxidative stress was measured using a human reconstructed epidermal (RHE) model according to levels of malondialdehyde (MDA), superoxide dismutase (SOD) and catalase.
Results:
Ascorbic acid 2-glucoside was completely metabolized to AA by the skin before entering the receptor compartment. The skin contained parent and AA, indicating a reserve of AA2G was present for further metabolism. For AA2G and AA, maximum flux of AA-equivalents was at 12 h, with continued absorption over 24 h. The absolute amount in µg was higher in the skin after application of AA than after application of AA2G. This may suggest a greater antioxidative effect; however, according to all three measurements of oxidative stress, the protective effect of AA and AA2G was similar. Unlike AA, AA2G was chemically stable under storage conditions.
Conclusion:
A lower concentration of AA2G is as effective as the active metabolite, AA, in terms of antioxidant effects. AA2G was chemically stable and can be applied at a lower concentration than AA, thus avoiding the need for an acidic formulation with a pH below 3.5.
... Besides that, the action of multiple targets in the therapeutic mechanism is also an important factor. VC can not only inhibit the transformation of tyrosine to pigment but also be antioxidant-promoting collagen synthesis (42). Antiphotoaging in the melasma area is recently considered to be an important strategy for melasma therapy. ...
Background: Melasma is an acquired pigmentation disorder with challenges in treatment because of its refractory nature and high risk of recurrence.
Objectives: This study aimed to compare the efficacy and side effects of 14 common therapies for melasma using a systematic review and network meta-analysis (NMA).
Methods: The PubMed, Embase, and Cochrane Library databases were searched till December 2020 using the melasma area and severity index as a therapeutic index. A total of 59 randomized controlled trials (RCTs) met the inclusion criteria and were selected.
Results: The ranking of relative efficacy compared with placebo in descending order was Q-switched Nd:Yag 1,064-nm laser (QSND), intense pulsed light, ablative fractional laser (AFL), triple combined cream (TCC), topical vitamin C, oral tranexamic acid (oTA), peeling, azelaic acid, microneedles (MNs), topical tranexamic acid (tTA), tretinoin, picosecond laser, hydroquinone (HQ), and non-AFL. Moreover, QSND was more effective than HQ and tTA against melasma. The ranking of percentage (%) of side effects in ascending order for each of 14 therapies with more than 80 participants was tretinoin (10.1%), oTA (17.6%), HQ (18.2%), AFL (20.0%), QSND (21.5%), TCC (25.7%), tTA (36.75%), peeling (38.0%), and MN (52.3%). Taking both efficacy and safety into consideration, TCC was found to be the most favorable selection among the topical drugs for melasma. QSND and AFL were still the best ways to treat melasma among photoelectric devices. oTA as system administration was a promising way recommended for melasma. Among 31 studies, 87% (27/31) studies showed that the efficacy of combination therapies is superior to that of single therapy. The quality of evidence in this study was generally high because of nearly 50% of split-face RCTs.
Conclusions: Based on the published studies, this NMA indicated that QSND, AFL, TCC, and oTA would be the preferred ways to treat melasma for dermatologists. However, more attention should be paid to the efficacy and safety simultaneously during the clinical application. Most of the results were in line with those of the previous studies, but a large number of RCTs should be included for validation or update.
Systematic Review Registration: identifier: CRD42021239203.
... Perricone et al. showed that AA-PAL has biologic activity that is not dependent on conversion to AA. 7,47 Rather, it is a free radical scavenger on its own and has advantages over AA in topical formulation. This study concluded that 15% AA-PAL was effective at reducing UVB-generated erythema. ...
Vitamin C is a popular ingredient in over‐the‐counter cosmeceuticals due to its many biological functions in maintaining and improving skin health by treating UV damage, improving discoloration, and boosting collagen production. Several chemically modified derivatives of vitamin C have been developed in an attempt to increase the stability, percutaneous absorption, and overall activity of this ingredient in topical formulations. The goal of this review is to evaluate the differences between vitamin C derivatives that have been designed for cosmeceutical use and their efficacy.
... Recovery of catalase following UVA exposure is also diminished in the skin of older subjects, which contributes to extrinsic skin aging [59]. To compensate for this decline in antioxidant defense, the use of topical AA or AA precursors has been proposed [60], but THDC alone may be counterproductive since even more H 2 O 2 may be generated as a degradation product [37]. Our results suggest that the use of combined THDC-AZ formulations may provide a more stable formulation to maximize ascorbate release. ...
Tetrahexyldecyl Ascorbate (THDC) is an L-ascorbic acid precursor with improved stability and ability to penetrate the epidermis. The stability and transdermal penetration of THDC, however, may be compromised by the oxidant-rich environment of human skin. In this study, we show that THDC is a poor antioxidant that degrades rapidly when exposed to singlet oxygen. This degradation, however, was prevented by combination with acetyl zingerone (AZ) as a stabilizing antioxidant. As a standalone ingredient, THDC led to unexpected activation of type I interferon signaling, but this pro-inflammatory effect was blunted in the presence of AZ. Moreover, the combination of THDC and AZ increased expression of genes associated with phospholipid homeostasis and keratinocyte differentiation, along with repression of MMP1 and MMP7 expression, inhibition of MMP enzyme activity, and increased production of collagen proteins by dermal fibroblasts. Lastly, whereas THDC alone reduced viability of keratinocytes exposed to oxidative stress, this effect was completely abrogated by the addition of AZ to THDC. These results show that AZ is an effective antioxidant stabilizer of THDC and that combination of these products may improve ascorbic acid delivery. This provides a step towards reaching the full potential of ascorbate as an active ingredient in topical preparations.
... Ascorbic acid protects the skin from oxidative stress via a sequential donation of its electrons to neutralize free radicals. Further, it reduces the production of ROS such as superoxide radicals, hydroxyl radicals and singlet oxygen molecules [118,119]. ...
Skin, our first interface to the external environment, is subjected to oxidative stress caused by a variety of factors such as solar ultraviolet, infrared, and visible light, environmental pollution, including ozone and particulate matters, and psychological stress. Excessive reactive species, including reactive oxygen species and reactive nitrogen species, exacerbate skin pigmentation and aging, which further lead to skin tone unevenness, pigmentary disorder, skin roughness, and wrinkles. Besides these, skin microbiota is also a very important factor ensuring the proper functions of skin. While environmental factors such as UV and pollutants impact skin microbiota compositions, skin dysbiosis results in various skin conditions. In this review, we summarize the generation of oxidative stress from exogenous and endogenous sources. We further introduce current knowledge on the possible roles of oxidative stress in skin pigmentation and aging, specifically with emphasis on oxidative stress and skin pigmentation. Meanwhile, we summarize the science and rationale of using three well‐known antioxidants, namely vitamin C, resveratrol, and ferulic acid, in the treatment of hyperpigmentation. Finally, we discuss the strategy for preventing oxidative stress‐induced skin pigmentation and aging.
Background: Aluminum chloride (AlCl3) toxicity is a growing concern due to its prevalence usage in various industrial and environmental settings. Prolonged exposure to aluminum chloride can lead to oxidative stress, electrolyte imbalances, and alterations in lipid metabolism. This study aimed to investigate the effects of supplementation of ascorbic acid and Massularia acuminata extracts on electrolyte function and lipid profile parameters in adult Wistar rats exposed to aluminum chloride toxicity. Methodology: The stem barks of Massularia acuminata were air-dried at room temperature for thirty (30) days and were mechanically ground into fine powder by using an electrical mill. The powder was kept in air-tight container until use. Six hundred (600 g) of the dried powders was dissolved in 4 litres of 80 % (v/v) of methanol, ethanol and butanol respectively for 72 h with occasional agitation using sterile rod. The resulting mixture obtained was then filtered using pieces of white cotton gauze and concentrated in a rotary evaporator following by dryness under vacuo at 40 0C in a rotary evaporator. The extracts that were obtained were then concentrated to dryness ‘in vacuo’ to yield the respective solvent extracts For the animal study, then, fifty Adult Wistar rats was randomly divided into several groups, including a control group, an aluminum chloride-exposed group, and treatment groups supplemented with ascorbic acid, Massularia acuminata extracts, and combination of both in varied doses. The dosage of supplementation was determined based on preliminary experiments and relevant literature. The rats in the aluminum chloride-exposed group and the treatment groups received oral administration of aluminum chloride at a specific dose of (34 mg/kg) for a defined duration to induce toxicity. The control group received a placebo. The treatment groups received supplementation of Ascorbic Acid and Massularia acuminata extracts received daily oral supplementation of ascorbic acid, Massularia acuminata extracts, or a combination of both, while the control and aluminum chloride-exposed groups received a placebo. Results: The result showed that there was a significant (p < 0.05) decrease in the lipid profile of Total Cholesterol (TC), Very Low-Density Lipoprotein (VLDL) and a non-significant decrease in High Density Lipoprotein (HDL) treated with vitamin C while a significant decrease in the level of HDL, VLDL, LDL and cholesterol were observed from the groups treated with the various plant extracts. Conclusion: From the study, it can therefore be concluded that ethanol leaf extract of Massularia acuminata has protective effect against aluminium chloride induced hepatotoxicity, oxidative stress and alterations in lipid and electrolyte profile in Wistar rats.
Background
Skin aging is inevitable. Wrinkles, skin texture abnormalities, senile hyperpigmentation, loss of skin tone, dryness, atrophy, and telangiectasias represent some of the hallmarks of aged skin. Skin rejuvenation can be addressed by topical therapies, such as topical retinoids and antioxidants or physical modalities with energy‐based devices, all providing acceptable outcomes. In this case series, we aimed to test the rejuvenating potential of the combination of cysteamine (a naturally occurring antioxidant) and isobionicamide (a derivative of the anti‐aging molecule niacinamide) applied topically.
Methods
Healthy male and female patients (N = 7) aged between 25 and 70 years and having Fitzpatrick skin types I–VI were recruited. Topical application of a cysteamine‐isobionicamide formula was done once daily. Treatment lasted for 16 weeks. Clinical high‐resolution photos were acquired using LifeViz 3D at recruitment and after 16 weeks. Blinded dermatological examinations and scoring were performed. Self‐assessment and quality of life (QoL) questionnaires were collected.
Results
Clinical photos showed improvement in skin luminosity, increased evenness of skin tone, and reduction of fine wrinkles as well as hyperpigmentation. Patients as well as clinical investigators blinded to the chronology of photos observed the improvements in skin texture, luminosity, and radiance, the brightening of the dark spots, as well as the reduction of both number and volume of wrinkles after 16 weeks of daily application. Furthermore, a significant improvement in patients' quality of life was recorded.
Conclusion
This case series represents the first evidence that topical application of cysteamine isobionic‐amide complex could be considered as a safe and effective option in the reversal of skin photoaging.
Kosmetik: Merujuk pada produk-produk perawatan kulit dan kecantikan yang digunakan untuk memperbaiki atau mempertahankan kondisi kulit dan penampilan fisik secara umum. Ini termasuk produk seperti krim pelembab, pembersih wajah, sunscreen, lipstick, dan lain-lain. Produk kosmetik fokus pada perbaikan estetika dan penampilan, dan dapat digunakan oleh siapa saja tanpa resep dokter.
Kosmeseutical: Istilah ini merupakan gabungan dari “kosmetik” dan “farmasi”. Kosmeseutical mengacu pada produk-produk yang memiliki manfaat kosmetik tetapi juga dirancang untuk menyediakan perawatan khusus bagi kondisi medis tertentu, seperti jerawat, sensitivitas kulit, atau penuaan. Produk-produk ini mungkin mengandung bahan-bahan aktif yang diakui secara ilmiah untuk membantu mengatasi masalah kulit tertentu, sering kali lebih kuat atau lebih konsentrasi daripada produk kosmetik biasa.
There is overwhelming evidence from in vitro and in vivo investigations as well as animal and human studies that incorporation of some vitamins in skincare products and cosmeceuticals promote healthy skin and re-engineer the skin to a healthy state. This comprehensive review illustrates the protective roles of vitamins A, B3, C, D, and E in skin- care products and cosmeceuticals. We have evaluated the impact of vitamin-based skincare products on the skin microbiomes and reviewed the popular vitamin-based cosmeceuticals. Our review also identifies the gaps in our knowledge for future research and describe the potential mechanisms of vitamins to promote skin health and reduce wrinkle formation in the ageing skin. The challenges and future opportunities in the area of cosmeceuticals and skincare products also are discussed, along with consumer perceptions, safety implications, and the comparison of dietary vitamin intake as opposed to topical applications. Overall, the aims of this review are to enhance our understanding regarding the physiological role of vitamins in skincare products and cosmeceuticals and to rejuvenate the skin towards healthy state. Such information would provide a valuable resource for consumers, dermatologists, and stakeholders in this important and evolving field of environmental skin protection and anti-aging research in elderly population.
Dalam buku "Garam Ajaib; Pemanfaatan Garam dalam Usaha Kosmetik," pembaca diajak untuk menjelajahi dunia kecantikan yang terbuka lebar oleh keajaiban garam. Dari dasar-dasar kimia hingga inovasi masa depan, buku ini menyuguhkan pengetahuan mendalam mengenai bagaimana garam, yang biasa kita temui di meja makan, mampu menjadi bintang dalam perawatan kulit.
Buku ini dimulai dengan memberikan landasan yang kuat, menggali definisi garam, jenis-jenisnya, dan proses pembuatannya. Pembaca diajak menyelami sifat-sifat kimia garam dan perannya dalam produk konsumsi sehari-hari. Bab demi bab, buku ini membuka tirai keajaiban garam dalam konteks kosmetik.
Eksplorasi dimulai dengan membahas peran garam dalam eksfoliasi kulit, membebaskan kulit dari sel-sel mati dan merangsang regenerasi sel-sel baru. Pembersihan alami dengan garam juga menjadi fokus, mengungkap bagaimana garam dapat menjadi agen pembersih alami yang efektif. Pembaca akan dibimbing melalui proses pembuatan scrub garam untuk pembersihan dalam, menciptakan pengalaman perawatan kulit yang menyegarkan.
Melangkah lebih jauh, buku ini mengulas bagaimana garam berperan sebagai bahan dasar dalam formulasi pembersih wajah alami. Pembaca akan memahami bagaimana garam tidak hanya membersihkan, tetapi juga melembapkan kulit, menciptakan kombinasi unik untuk perawatan kulit yang holistik.
Puncaknya, buku ini membawa pembaca ke masa depan pemanfaatan garam dalam industri kosmetik. Dari perkembangan teknologi yang menjanjikan hingga potensi inovasi lebih lanjut, buku ini menutup dengan membahas tantangan dan peluang yang mungkin dihadapi di masa mendatang.
"Garam Ajaib; Pemanfaatan Garam dalam Usaha Kosmetik " bukan hanya kumpulan fakta ilmiah, tetapi juga perjalanan inspiratif yang menggugah pembaca untuk lebih cermat memilih produk kecantikan yang ramah lingkungan dan alami. Dengan gaya penulisan yang jelas dan mengundang, buku ini menghadirkan keindahan dan keajaiban garam dalam membantu kita merawat kulit, menjadikannya panduan tak tergantikan bagi pecinta kosmetik dan pemerhati kecantikan alami.
The term cosmeceutical refers to a category of skincare products that are purported to have active ingredients whose physiological or pharmacological actions are capable of inducing cosmetic enhancements to the skin. Given a demand for brighter, healthier, younger‐appearing skin, and relatively limited regulatory control, thousands of different cosmeceutical formulations have found their way onto store shelves and onto the skin of hopeful consumers, despite a lack of scientific evidence. This chapter summarizes new and old, common and rare cosmeceutical ingredients; their uses and side effects; and the science, where available, behind the claims.
Demand on natural products that contain biological ingredients mimicking growth factors and cytokines made natural polysaccharides popular in pharmaceutical and cosmetic industries. Levan is the β-(2-6) linked, nontoxic, biocompatible, water-soluble, film former fructan polymer that has diverse applications in pharmacy and cosmeceutical industries with its moisturizing, whitening, anti-irritant, anti-aging and slimming activities. Driven by the limited reports on few structurally similar levan polymers, this study presents the first systematic investigation on the effects of structurally different extremophilic Halomonas levan polysaccharides on human skin epidermis cells. In-vitro experiments with microbially produced linear Halomonas levan (HL), its hydrolyzed, (hHL) and sulfonated (ShHL) derivatives as well as enzymatically produced branched levan (EL) revealed increased keratinocyte and fibroblast proliferation (113-118 %), improved skin barrier function through induced expressions of involucrin (2.0 and 6.43 fold changes for HL and EL) and filaggrin (1.74 and 3.89 fold changes for hHL and ShHL) genes and increased type I collagen (2.63 for ShHL) and hyaluronan synthase 3 (1.41 for HL) gene expressions together with fast wound healing ability within 24 h (100 %, HL) on 2D wound models clearly showed that HL and its derivatives have high potential to be used as natural active ingredients in cosmeceutical and skin regenerating formulations.
L-ascorbic acid （Vitamin C, VC） is the most abundant antioxidant in human skin. But its poor penetration into the skin and unstability limit the application. The aim of the study was to promote the topical skin permeation and retention of VC, increase the stability as well as effectiveness by a novel solid in oil nanodispersion. In the nanodispersions system, nano-sized particles of hydrophilic molecules are dispersed in an oil vehicle with the assistance of hydrophobic surfactants. The optimized formula composed of O170 and S1570 (12.5:1, w/w) showed high EE% of 98% and good stability. FTIR analysis confirmed that there may be hydrogen bond between VC and surfactants. The results of DSC, and XRD revealed that the drug was successfully encapsulated in the surfactants, which maintained the stability of drug. By analyzing and fitting the release data in vitro, the drug release mechanism of SONDs was predicted as a multi-dynamic model. Skin permeation of VC was improved 3.43-fold for SONDs compared with VC aqueous solution, highlighting that the lipophilicity and nano size of the carrier more easily penetrated into the skin. Finally, the photoaging study revealed that topical application of VC-SONDs provided the highest skin protection compared UV and VC aqueous solution treated group which was evident by the normal thick epidermal morphology, no obvious melanocytes and the densely arranged dermal elastic fibers. These results demonstrated that the solid-in-oil nanodispersions may be a potential transdermal delivery system for hydrophilic bioactive ingredients.
The skin is a physical barrier that protects our body against various environmental, chemical and physical agents, and is the main organ that is easily visible as time progresses. Aging is a dynamic, progressive and undesirable biological process that unfortunately cannot be stopped, according to present knowledge. Intrinsic aging (chronological, spontaneous and biological aging) is a programmed natural process, while extrinsic aging (environmental aging and photoaging) is associated with sun exposure, smoking and malnutrition, which weakens the skin structure and functions. Over time, aging skin starts to lose elastin fibers, collagen and other proteins, which are the basic constituents that make skin healthy, bright, fit and elastic. There has been increasing interest in studies on various molecular and hormonal mechanisms, such as hormone dysfunction, changes in signaling pathways, the downregulation of mitochondrial function with cytokine increase, and mitochondrial DNA mutation. Antiaging treatment strategies can be divided into two parts: primary (basic) preventive antiaging approaches and secondary antiaging approaches after the phenotypic features of aging are revealed. The present study aims to review the literature information on the underlying causes of skin aging, healthy skin aging, and basic protective antiaging approaches. Understanding the extrinsic and intrinsic pathophysiological processes of aging would increase the effectiveness of future treatment-finding efforts.
The purpose of the study was to analyse and update consumers’ changing preferences in the choice of citrus fruit juices and to evaluate the sensory and physicochemical characteristics of two kinds of juices: juice squeezed from raw fruit and a commercial juice indicated by respondents as best matching their preferences. The survey was conducted in the form of an online survey posted on app.ankieteo.pl. The survey was also sent via a link through social networks. A total of 862 people took part in the survey. Consumers are most likely to consume juices one to three times a week (28.3%). Orange juice was the most popular among respondents (52.4%). The main factors influencing decisions to purchase citrus fruit juices are the type of fruit from which the juice was made, the vitamin content and the product’s price. In choosing juices, respondents were also guided by favourable health qualities and the presence of minerals. From the physicochemical determinations of orange juices obtained from a juicer and squeezer and commercial juice “O”, it was found that the quality of commercial orange juice indicated by consumers in the survey is comparable to juices made with a squeezer or a juice.
Background
the topical use of vitamin C has been explored for many decades due to its antioxidant potential, whitening action, and the essential role it plays in the synthesis and maintenance of collagen. As Ascorbic Acid (AA) is unstable, derivative molecules and stabilization strategies have been explored to facilitate its incorporation into dermatological products. Even though these molecules are already for sale, there is still a shortage of scientific data regarding efficacy studies of these assets, especially in vivo.
Objective
the purpose of this review was to investigate and discuss issues regarding the topical application of vitamin C and its most common derivatives, including the difficulties, biases, and prospects for future clinical studies to better elucidate its effects.
Method
a literature review was carried out to select studies that evaluated the topical use of ascorbic acid and/or its derivatives. The studies which are “fully available”, “in vivo”, and “in vitro” were used as inclusion criteria.
Results
due to the instability of Ascorbic Acid, it is essential to study derivative molecules that maintain or even improve their effectiveness in dermatological products. Despite this, the studies of these derivatives, presented in the scientific literature, are mostly in vitro. In recent years, it has been possible to observe an increase in in vivo efficacy tests, and this trend is expected to continue in the future. However, they present very different approaches and issues.
Conclusion
studies of stability, safety, adverse reactions, and especially in vivo efficacy studies with a relevant number of subjects and standardized parameters are essential for better elucidating the effects of the topical application of vitamin C derivatives in comparison with ascorbic acid formulations for the skin.
Introduction:
Vitamins C, E, A and substances of plant origin, including azelaic acid and phytic acid are frequently used in cosmetic preparations to counteract oxidative stress and negative effects of free radicals. The aim of the study was to evaluate a novel combined therapy consisting of azelaic acid, ascorbic acid, and phytic acid applied layer on layer.
Methods:
Twenty study participants received a series of eight treatments performed every seven days. 20% azelaic acid and then 30% phytic acid were applied to the entire face, while 40% L-ascorbic acid only on the left side. The preparations were applied layer by layer. Skin parameters were measured before the series of treatments (T0), after the series of eight treatments (T1 - 8 weeks) and one month after the end of the treatment (T2 - 12 weeks).
Results:
The application of two and three active compounds resulted in a significant improvement in erythema and hyperpigmentation both on the forehead and the cheeks, however, more pronounced effects were observed when all the three active compounds were used. Both applied types of treatment considerably increased skin moisture. All the participants (100%) were satisfied with the effects of the treatment. A majority of them reported an improvement in skin hydration, firmness and elasticity, more uniform skin tone and a reduction of skin redness and wrinkles.
Conclusions:
Topical application of these active compounds resulted in improvement of skin elasticity and flexibility, reduction of wrinkles, hyperpigmentation, erythema and telangiectasia as well as amelioration of skin tone.
Introduction
Damage to human skin occurs either chronologically or through repetitive exposure to ultraviolet (UV) radiation, where collagen photodegradation leads to the formation of wrinkles and skin imperfections. Consequently, cosmeceutical products containing natural bioactives to restore or regenerate collagen have gained a remarkable attention as an ameliorative remedy.
Methods
This study aimed to develop and optimize collagen-loaded water-in-oil nanoemulsion (W/O NE) through a D-optimal mixture design to achieve an ideal multifunctional nanosystem containing active constituents. Vit E was included as a constituent of the formulation for its antioxidant properties to minimize the destructive impact of UV radiation. The formulated systems were characterized in terms of their globule size, optical clarity, and viscosity. An optimized system was selected and evaluated for its physical stability, in vitro wound healing properties, and in vivo permeation and protection against UV radiation. In addition, the effect of collagen-loaded NE was compared to Vit C-loaded NE and collagen-/Vit C-loaded NEs mixture as Vit C is known to enhance collagen production within the skin.
Results
The optimized NE was formulated with 25% oils (Vit E: safflower oil, 1:3), 54.635% surfactant/cosurfactant (Span 80: Kolliphor EL: Arlasolve, 1:1:1), and 20.365% water. The optimized NE loaded with either collagen or Vit C exhibited a skin-friendly appearance with boosted permeability, and improved cell viability and wound healing properties on fibroblast cell lines. Moreover, the in vivo study and histopathological investigations confirmed the efficacy of the developed system to protect the skin against UV damage. The results revealed that the effect of collagen-/Vit C-loaded NEs mixture was more pronounced, as both drugs reduced the skin damage to an extent that it was free from any detectable alterations.
Conclusion
NE formulated using Vit E and containing collagen and/or Vit C could be a promising ameliorative remedy for skin protection against UVB irradiation.
Foods can affect the physical, mental, and emotional aspects of our lives and determine our overall health and productivity. Whether we eat chicken nuggets, apples, or watermelon, food is a vital source of energy that keeps the body’s tissues and organs going during our day-to-day activities. In this article, we examine how various nutrients from foods affect the skin and its ability to protect the body from infections and the elements of the environment. In addition, we briefly discuss a patient who had a wound that was taking a long time to heal, which required surgery to fix. Recommending the right nutrition led to complete healing and cancellation of the surgery.
background.Aging of the population, in particular the “baby boomers,” has resulted in increased interest in methods of reversal of photodamage. Non-invasive treatments are in high demand, and our knowledge of mechanisms of photodamage to skin, protection of the skin, and repair of photodamage are becoming more sophisticated and complex.objective.The objective of this study is to determine if the topical use of a vitamin C preparation can stimulate the skin to repair photodamage and result in clinically visible differences, as well as microscopically visible improvement.methods.Ten patients applied in a double-blind manner a newly formulated vitamin C complex having 10% ascorbic acid (water soluble) and 7% tetrahexyldecyl ascorbate (lipid soluble) in an anhydrous polysilicone gel base to one-half of the face and the inactive polysilicone gel base to the opposite side. Clincial evaluation of wrinkling, pigmentation, inflammation, and hydration was performed prior to the study and at weeks 4, 8, and 12. Two mm punch biopsies of the lateral cheeks were performed at 12 weeks in four patients and stained with hematoxylin and eosin, as well as in situ hybridization studies using an anti-sense probe for mRNA for type I collagen. A questionnaire was also completed by each patient.results.A statistically significant improvement of the vitamin C-treated side was seen in the decreased photoaging scores of the cheeks (P = 0.006) and the peri-oral area (P = 0.01). The peri-orbital area improved bilaterally, probably indicating improved hydration. The overall facial improvement of the vitamin C side was statistically significant (P = 0.01). Biopsies showed increased Grenz zone collagen, as well as increased staining for mRNA for type I collagen. No patients were found to have any evidence of inflammation. Hydration was improved bilaterally. Four patients felt that the vitamin C-treated side improved unilaterally. No patient felt the placebo side showed unilateral improvement.conclusion.This formulation of vitamin C results in clinically visible and statistically significant improvement in wrinkling when used topically for 12 weeks. This clinical improvement correlates with biopsy evidence of new collagen formation.
Proliferation of human skin fibroblasts was stimulated significantly by the presence of L-ascorbic acid 2-phosphate (Asc 2-P). The presence of Asc 2-P (0.1–1.0 mM) in the culture medium for 3 weeks enhanced the relative rate of collagen synthesis to total protein synthesis 2-fold as well as cell growth 4-fold. Coexistence of L-azetidine 2-carboxylic acid (AzC), an inhibitor of collagen synthesis, attenuated both effects of Asc 2-P in a dose-dependent manner. Supplementation of the medium with Asc 2-P also accelerated procollagen processing to collagen and deposition of collagen in the cell layer. Among the acidic glycosaminoglycans (GAG), another major component of extracellular matrix (ECM), deposition of sulfated forms was increased by the additive. Electron microscopic observations showed multilayered, rough endoplasmic reticulum-rich cells surrounded by dense ECM. These results indicate that Asc 2-P is useful in culture systems as a long-acting vitamin C derivative and also that it promotes reorganization of a three-dimensional tissuelike substance from skin fibroblasts in culture by stimulating collagen accumulation in the fibroblasts.
Background:
Reactive oxygen species generated by ultraviolet light result in photocarcinogenic and photoaging changes in the skin. Antioxidants protect skin from these insults.
Objective:
This study defines formulation characteristics for delivering L-ascorbic acid into the skin to supplement the skin's natural antioxidant reservoir.
Methods:
L-ascorbic acid or its derivatives were applied to pig skin. Skin levels of L-ascorbic acid were measured to determine percutaneous delivery.
Results:
L-ascorbic acid must be formulated at pH levels less than 3.5 to enter the skin. Maximal concentration for optimal percutaneous absorption was 20%. Tissue levels were saturated after three daily applications; the half-life of tissue disappearance was about 4 days. Derivatives of ascorbic acid including magnesium ascorbyl phosphate, ascorbyl-6-palmitate, and dehydroascorbic acid did not increase skin levels of L-ascorbic acid.
Conclusions:
Delivery of topical L-ascorbic acid into the skin is critically dependent on formulation characteristics.
Recombinant human epidermal growth factor (EGF, 2-10 ng/ml) stimulated growth and production of non-collagenous proteins, but inhibited production of collagen by 60% in cultured human skin fibroblasts. Type analysis of the collagen produced indicated that inhibition of the collagen production observed was mainly a reflection of a reduction in type I collagen. The accumulation of pro alpha 1(I) and pro alpha 2(I) mRNAs and the transcriptional activity of these genes were determined in human skin fibroblasts in order to investigate site(s) of regulation of type I collagen production by human EGF in the absence and presence of L-ascorbic acid 2-phosphate (Asc 2-P), a long-acting vitamin C derivative. Human EGF (10 ng/ml) used alone reduced the steady state levels of mRNAs for pro alpha 1(I) and pro alpha 2(I) chains and transcriptional activity of these genes in vitro by 45%. Asc 2-P (0.2 mM) alone, on the other hand, raised production of type I collagen and the steady state levels of mRNAs for pro alpha 1(I) and pro alpha 2(I) collagen chains as well as stimulated transcriptional activity of these genes. Human EGF attenuated these stimulative effects of Asc 2-P. These results indicate that human EGF regulates type I collagen synthesis at the transcriptional level in cultured fibroblasts in the presence and absence of Asc 2-P. The possibility that human EGF plays a role as a regulator of type I collagen genes in vivo was discussed.
Man is among the exceptional higher animals that are unable to synthesize L-ascorbic acid because of their deficiency in L-gulono-gamma-lactone oxidase, the enzyme catalyzing the terminal step in L-ascorbic acid biosynthesis. In the present study, we isolated a segment of the nonfunctional L-gulono-gamma-lactone oxidase gene from a human genomic library, and mapped it on chromosome 8p21.1 by spot blot hybridization using flow-sorted human chromosomes and fluorescence in situ hybridization. Sequencing analysis indicated that the isolated segment represented a 3'-part of the gene, where the regions corresponding to exons VII, IX, X, and XII of the rat L-gulono-gamma-lactone oxidase gene remain with probable deletion of the regions corresponding to exons VIII and XI. In the identified exon regions were found various anomalous nucleotide changes, such as deletion and insertion of nucleotide(s) and nonconformance to the GT/AG rule at intron/exon boundaries. When the conceptual amino acid sequences deduced from the four exon sequences were compared with the corresponding rat sequences, there were a large number of nonconservative substitutions and also two stop codons. These findings indicate that the human nonfunctional L-gulono-gamma-lactone oxidase gene has accumulated a large number of mutations without selective pressure since it ceased to function during evolution.
Under normal physiological conditions, the use of oxygen by cells of aerobic organisms generates potentially deleterious reactive
oxygen metabolites. A chronic state of oxidative stress exists in cells because of an imbalance between prooxidants and antioxidants.
The amount of oxidative damage increases as an organism ages and is postulated to be a major causal factor of senescence.
Support for this hypothesis includes the following observations: (i) Overexpression of antioxidative enzymes retards the age-related
accrual of oxidative damage and extends the maximum life-span of transgenic Drosophila melanogaster. (ii) Variations in longevity among different species inversely correlate with the rates of mitochondrial generation of the
superoxide anion radical (O·−2) and hydrogen peroxide. (iii) Restriction of caloric intake lowers steady-state levels of oxidative stress and damage, retards
age-associated changes, and extends the maximum life-span in mammals.
Ascorbate contributes to several metabolic processes including efficient hydroxylation of hydroxyproline in elastin, collagen,
and proteins with collagenous domains, yet hydroxyproline in elastin has no known function. Prolyl hydroxylation is essential
for efficient collagen production; in contrast, ascorbate has been shown to decrease elastin accumulation in vitro and to alter morphology of elastic tissues in vivo. Ascorbate doses that maximally stimulated collagen production (10-200 μM) antagonized elastin biosynthesis in vascular smooth muscle cells and skin fibroblasts, depending on a combination of dose
and exposure time. Diminished elastin production paralleled reduced elastin mRNA levels, while collagen I and III mRNAs levels
increased. We compared the stability of mRNAs for elastin and collagen I with a constitutive gene after ascorbate supplementation
or withdrawal. Ascorbate decreased elastin mRNA stability, while collagen I mRNA was stabilized to a much greater extent.
Ascorbate withdrawal decreased collagen I mRNA stability markedly (4.9-fold), while elastin mRNA became more stable. Transcription
of elastin was reduced 72% by ascorbate exposure. Differential effects of ascorbic acid on collagen I and elastin mRNA abundance
result from the combined, marked stabilization of collagen mRNA, the lesser stability of elastin mRNA, and the significant
repression of elastin gene transcription.
The stability of ascorbic acid, ascorbyl palmitate and magnesium ascorbyl phosphate (VC-PMG) in both standard solutions and topical formulations was investigated by direct RP-HPLC analysis after sample dilution with a suitable aqueous-organic solvent mixture. The results showed that, whereas the two vitamin C derivatives were more stable than ascorbic acid, the ascorbyl esters showed significant differences. Esterification with palmitic acid in 6 position did not prevent hydrolysis of the molecule, either in solution or in emulsion; only the special preparation of products with high viscoelastic properties was able to reduce the typical behaviour of this compound. Conversely, the introduction of the phosphoric group in 2 position protected the molecule from break-up of the enediol system, confirming VC-PMG as a very stable derivative of vitamin C that may be easily used in various types of cosmetic products.
The recently released Recommended Dietary Allowance of vitamin C for women, 75 mg daily, was based on data for men. We now report results of a depletion-repletion study with healthy young women hospitalized for 186 +/- 28 days, using vitamin C doses of 30-2,500 mg daily. The relationship between dose and steady-state plasma concentration was sigmoidal. Only doses above 100 mg were beyond the linear portion of the curve. Plasma and circulating cells saturated at 400 mg daily, with urinary elimination of higher doses. Biomarkers of endogenous oxidant stress, plasma and urine F(2)-isoprostanes, and urine levels of a major metabolite of F(2)-isoprostanes were unchanged by vitamin C at all doses, suggesting this vitamin does not alter endogenous lipid peroxidation in healthy young women. By using Food and Nutrition Board guidelines, the data indicate that the Recommended Dietary Allowance for young women should be increased to 90 mg daily.
Virtually all plants and animals protect themselves from the sun using vitamins C and E.
The purpose of this study was to see if a combination of topical vitamins C and E is better for UV protection to skin than an equivalent concentration of topical vitamin C or E alone.
We developed a stable aqueous solution of 15% L-ascorbic acid (vitamin C) and 1% alpha-tocopherol (vitamin E). We applied antioxidant or vehicle solutions to pig skin daily for 4 days. We irradiated (1-5x minimal erythema dose) control- and antioxidant-treated skin using a solar simulator with a 295-nm band-pass filter. On day 5, we measured antioxidant protection factor, erythema, sunburn cells, and thymine dimers.
The combination of 15% L-ascorbic acid and 1% alpha-tocopherol provided significant protection against erythema and sunburn cell formation; either L-ascorbic acid or 1% alpha-tocopherol alone also was protective but the combination was superior. Application during 4 days provided progressive protection that yielded an antioxidant protection factor of 4-fold. In addition, the combination of vitamins C and E provided protection against thymine dimer formation.
Appreciable photoprotection can be obtained from the combination of topical vitamins C and E. We suggest that these natural products may protect against skin cancer and photoaging.
The purpose of this open-label study was to determine the safety and efficacy of sodium L-ascorbyl-2-phosphate (5% W/V) (APS) lotion, used after glycolic acid (GA) peels, compared with a vehicle application for the treatment of acne scars in 70 Japanese patients (59 completed the study). A GA solution with 50% concentration and pH 2.0 was used in the study. The group treated with APS showed greater improvement than the group that received vehicle application for the treatment of facial acne scars. Because APS was well tolerated and has shown a variety of beneficial effects on the skin, the authors concluded that APS has potential applications to treat various skin disorders.
Ascorbic acid (vitamin C) is a cofactor required for the function of several hydroxylases and monooxygenases. It is not synthesized in humans and some other animal species and has to be provided by diet or pharmacologic means. Its absence is responsible for scurvy, a condition related in its initial phases to a defective synthesis of collagen by the reduced function of prolylhydroxylase and production of collagen polypeptides lacking hydroxyproline, therefore, they are unable to assemble into stable triple-helical collagen molecules. In fibroblast cultures, vitamin C also stimulates collagen production by increasing the steady-state level of mRNA of collagen types I and III through enhanced transcription and prolonged half-life of the transcripts. The aim of the experimental work has been to evaluate the effect on dermal cells of a preparation of vitamin C topically applied on one side vs placebo on the other side of the dorsal face of the upper forearm of postmenopausal women. Biopsies were collected on both sides and the level of mRNA measured by non competitive reverse transcription–polymerase chain reaction made quantitative by the simultaneous transcription and amplification of synthetic RNA used as internal standards. The mRNA of collagen type I and type III were increased to a similar extent by vitamin C and that of three post-translational enzymes, the carboxy- and amino-procollagen proteinases and lysyloxidase similarly increased. The mRNA of decorin was also stimulated, but elastin, and fibrillin 1 and 2 were not modified by the vitamin. The expression of matrix metalloproteinases 1, 2, and 9 was not significantly changed, but an increased level of tissue inhibitor of matrix metalloproteinase 1 mRNA was observed without modification of tissue inhibitor of matrix metalloproteinase 2 mRNA. The stimulating activity of topical vitamin C was most conspicuous in the women with the lowest dietary intake of the vitamin and unrelated to the level of actinic damage. The results indicate that the functional activity of the dermal cells is not maximal in postmenopausal women and can be increased.Keywords: ADAMTS2, BMP1, decorin, elastin, matrix metalloproteinases
We measured enzymic and non-enzymic antioxidants in human epidermis and dermis from six healthy volunteers undergoing surgical procedures. Epidermis was separated from dermis by currettage and antioxidants were measured by high-performance liquid chromatography (HPLC) or standard spectrophotometric methods. The concentration of every antioxidant (referenced to skin wet weight) was higher in the epidermis than in the dermis.
Among the enzymic antioxidants, the activities of superoxide dismutase, glutathione peroxidase, and glutathione reductase were higher in the epidermis compared to the dermis by 126, 61 and 215%, respectively. Catalase activity in particular was much higher (720%) in the epidermis. Glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase, which provide reduced nicotinamide adenine dinucleotide phosphate (NADPH), also showed higher activity in the epidermis than the dermis by 111% and 313%, respectively.
Among the lipophilic antioxidants, the concentration of α-tocopherol was higher in the epidermis than the dermis by 90%. The concentration of ubiquinol 10 was especially higher in the epidermis, by 900%. Among the hydrophilic antioxidants, concentrations of ascorbic acid and uric acid were also higher in the epidermis than in the dermis by 425 and 488%, respectively. Reduced glutathione and total glutathione were higher in the epidermis than in the dermis by 513 and 471%.
Thus the antioxidant capacity of the human epidermis is far greater than that of dermis. As the epidermis composes the outermost 10% of the skin and acts as the initial barrier to oxidant assault, it is perhaps not surprising that it has higher levels of antioxidants.
Extracellular stimuli signal for activation of the transcription factor NFκB, leading to gene expression regulating processes involved in immune responses, inflammation, and cell survival. Tumor necrosis factor-α (TNFα) activates NFκB via a well-defined kinase pathways involving NFκB-inducing kinase (NIK), which activates downstream multisubunit IκB kinases (IKK). IKK in turn phosphorylates IκB, the central regulator of NFκB function. We found that intracellular vitamin C inhibits TNFα-induced activation of NFκB in human cell lines (HeLa, monocytic U937, myeloid leukemia HL-60, and breast MCF7) and primary endothelial cells (HUVEC) in a dose-dependent manner. Vitamin C is an important antioxidant, and most cells accumulate ascorbic acid (AA) intracellularly by transporting the oxidized form of the vitamin, dehydroascorbic acid (DHA). Because ascorbic acid is a strong pro-oxidant in the presence of transition metals in vitro, we loaded cells with vitamin C by incubating them with DHA. Vitamin C-loaded cells showed significantly decreased TNFα-induced nuclear translocation of NFκB, NFκB-dependent reporter transcription, and IκBα phosphorylation. Our data point to a mechanism of vitamin C suppression of NFκB activation by inhibiting TNFα-induced activation of NIK and IKKβ kinases independent of p38 MAP kinase. These results suggest that intracellular vitamin C can influence inflammatory, neoplastic, and apoptotic processes via inhibition of NFκB activation.
Postoperative erythema of several months duration is a universal and problematic side effect of cutaneous carbon dioxide (CO2) laser resurfacing.
This study was conducted in order to determine the effectiveness of two formulations of topical ascorbic acid in reducing the degree and duration of post-CO2 laser resurfacing erythema.
The application of topical L-ascorbic acid in an aqueous formulation resulted in a significant decrease in post-CO2 laser resurfacing erythema by the eighth postoperative week when compared with laser-irradiated skin that had not received topical vitamin C. The application of topical ascorbic acid in a cream formulation did not result in a significant reduction in post-CO2 laser resurfacing erythema.
Topical L-ascorbic acid, when used in an appropriate vehicle and when initiated at an appropriate postoperative period, may decrease the degree and duration of erythema after cutaneous CO2 laser resurfacing. It is presumed that the anti-inflammatory effect of vitamin C is responsible for the clinical changes observed in this study.
Ultraviolet radiation damage to the skin is due, in part, to the generation of reactive oxygen species. Vitamin C (L-ascorbic acid) functions as a biological co-factor and antioxidant due to its reducing properties. Topical application of vitamin C has been shown to elevate significantly cutaneous levels of this vitamin in pigs, and this correlates with protection of the skin from UVB damage as measured by erythema and sunburn cell formation. This protection is biological and due to the reducing properties of the molecule. Further, we provide evidence that the vitamin C levels of the skin can be severely depleted after UV irradiation, which would lower this organ's innate protective mechanism as well as leaving it at risk of impaired healing after photoinduced damage. In addition, vitamin C protects porcine skin from UVA-mediated phototoxic reactions (PUVA) and therefore shows promise as a broad-spectrum photoprotectant.
The effect of topical application of ascorbic acid (AA) and ascorbyl palmitate (AP) on 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced tumor promotion in mouse skin was investigated. A single application of TPA decreased epidermal AA by 45%. Repetitive application of 6 and 28 mumol AA with 2 nmol TPA inhibited tumor multiplicity by 39% and 76%. Repetitive application of 0.16, 0.8, and 4.0 mumol AA with 5 nmol TPA inhibited tumor multiplicity by 16%, 46%, and 91%. Because AA may be poorly absorbed cutaneously, we evaluated the effect of dietary AA. Supplementation of drinking water with AA increased epidermal ascorbic acid levels by 50%. Dietary intake of AA did not inhibit TPA-induced tumor promotion. Preliminary data suggest that the mice not receiving AA developed increased epidermal AA levels in response to the tumor promoting regimen. Recently we have found that dietary AP inhibited TPA-induced biochemical parameters associated with tumor promotion.
Albino hairless mice (Skh:HR-1) exposed chronically to suberythemal doses of ultraviolet radiation develop visible skin changes, histological alterations, and tumors. Topical treatment of mice with solutions of superoxide-scavenging antioxidants (such as alpha-tocopherol, ascorbic acid, propyl gallate and Trolox) prior to each UVB radiation exposure reduced significantly the severity of these events. Tocopherol esters and ascorbyl palmitate were not as effective as the parent compounds in providing protection. The data suggest a role for superoxide in UVB radiation-induced skin photoaging and the protective potential of superoxide scavengers. In contrast, the severity of UVA radiation-induced mouse skin damage was not reduced by topical application of the antioxidants tested here.
The free radical theory proposes that photoaging, which is both qualitatively and quantitatively different from chronological aging, may result from imperfect protection against cumulative stress of free radicals produced by chronic and repeated ultraviolet irradiation. Since the skin is always in contact with oxygen and is occasionally exposed to ultraviolet light, skin is one of the best target organs of environmental photo-oxidative stress. A growing body of evidence suggests that reactive oxygen species are generated by ultraviolet irradiation resulting in the structural and functional alteration of cutaneous components which should affect the photoaging process over a long period. The age-related alteration of cutaneous antioxidant defense capacity against cumulative effects of continual photo-oxidative stress to the skin may also affect the photoaging. Thus the possible use of antioxidants that attenuate photo-oxidative toxicity is believed to be an important strategy modulating photoaging. Several antioxidants have readily been proved to work in the experimental conditions. This paper reviews photoaging from a photo-oxidative standpoint and discusses the possible regulation of photoaging by antioxidants that is an important issue in the photodermatological field.
Ascorbic acid has been shown to stimulate collagen synthesis in dermal fibroblasts by increasing the rate of transcription of collagen genes. Experiments involving the use of ascorbic acid require daily supplementation due to the instability of the molecule in aqueous solutions. In order to provide a more stable alternative to ascorbic acid, two salts of ascorbyl-2-phosphate, having a greater chemical stability than ascorbic acid, were tested for their ability to stimulate collagen synthesis in monolayer fibroblast cultures. The concentration and time dependence of their activities were compared with ascorbic acid. The magnesium salt of ascorbyl-2-phosphate was found to be equivalent to ascorbic acid in stimulating collagen synthesis in these assays, while the sodium salt required at least a tenfold greater concentration to produce the same effect as ascorbic acid. Solutions of either ascorbic acid or the ascorbyl-2-phosphate analogs (at 10 mM) in phosphate-buffered saline (PBS) were relatively stable as shown by their decay rates and their ability to stimulate collagen synthesis even after nine days in solution prior to testing their effects on cultured cells. Ascorbic acid was unstable at neutral pH compared to solutions of either sodium or magnesium ascorbyl-2-phosphate. These data support the use of magnesium ascorbyl-2-phosphate in experiments where stability of ascorbic acid is a concern, e.g. in long-term cultures or in in vivo studies.
An inhibitory effect of ascorbic acid (AsA) on melanogenesis has been described. However, AsA is quickly oxidized and decomposed in aqueous solution and thus is not generally useful as a depigmenting agent.
Our purpose was to examine the effect on pigmentation of magnesium-L-ascorbyl-2-phosphate (VC-PMG), a stable derivative of AsA.
Percutaneous absorption of VC-PMG was examined in dermatomed human skin, and its effect on melanin production by mammalian tyrosinase and human melanoma cells in culture was also measured. A 10% VC-PMG cream was applied to the patients.
VC-PMG suppressed melanin formation by tyrosinase and melanoma cells. In situ experiments demonstrated that VC-PMG cream was absorbed into the epidermis and that 1.6% remained 48 hours after application. The lightening effect was significant in 19 of 34 patients with chloasma or senile freckles and in 3 of 25 patients with normal skin.
VC-PMG is effective in reducing skin hyperpigmentation in some patients.
Ascorbic acid is a potent stimulator for type I and III collagen expression in human skin fibroblasts; stimulation of type I and III collagen synthesis and their mRNA levels by ascorbic acid has been reported previously. Nuclear run-on experiments demonstrated that ascorbic acid enhanced the transcription of type I and III collagen genes 4- and 3.4-fold respectively, whereas transcription of type IV collagen was slightly stimulated (1.7-fold). The results suggest that ascorbic acid preferentially enhanced type I and III collagen transcription.
The protective effect of magnesium-L-ascorbyl-2-phosphate (MAP) on cutaneous photodamage such as lipid peroxidation and inflammation induced by ultraviolet B (UVB) exposure (290-320 nm, max. 312 nm) was investigated using hairless mice. When MAP was administered intraperitoneally to mice at a dose of 100 mg of ascorbic acid (AS) per kg body weight base immediately before irradiation (15 kj/m2), the expected increases in thiobarbituric acid reactive substance (TBARS) formation in skin and serum sialic acid, indices of lipid peroxidation and inflammatory reaction, respectively, were significantly reduced. However, the expected decrease in the level of cutaneous AS was unchanged. Similar results were observed for animals given 100 mg of AS-Na per kg body weight before UVB irradiation. When MAP was administered intracutaneously immediately before irradiation, the expected UVB-induced increases in TBARS and sialic acid were again significantly prevented. Ascorbic acid-Na had a less protective effect than intracutaneous MAP administration. The cutaneous AS level was significantly higher in the MAP-treated mice than in the controls, and the UVB-induced decrease in tissue AS was prevented by intracutaneous MAP administration. These results suggest that MAP protects against UVB irradiation-induced lipid peroxidation and inflammation in cutaneous tissue, regardless of the drug administration route. We found, in an in vitro experiment, that MAP was converted to AS as it crossed the epidermis, but that AS-Na did not pass through the epidermis. Furthermore, MAP was also converted to AS in serum. These results suggest that the protective effect of MAP on UVB-induced cutaneous damage is due to conversion of MAP to AS.
Mouse skin was exposed to UVA radiation (320-400 nm). The in vivo chemiluminescence of the skin was measured after irradiation. Chemiluminescence showed a maximum 13-fold increase (control emission, 10 +/- 1 cps cm-2) after 45-60 min of exposure to UVA, with no further increase with 60 min additional exposure. Spectral analysis of the emitted chemiluminescence showed that the principal species emitted in the 400-500 nm range. Topical application with alpha-tocopherol (10% v/w) and beta-carotene (1 mM) greatly reduced the UVA-induced skin chemiluminescence. Thiobarbituric acid reactive substance (TBARS) levels were increased by 130% in skin homogenates after 2 h of exposure to UVA (control value, 77 +/- 14 nmol malonaldehyde equivalents (g tissue)-1). The activities of antioxidant enzymes in skin homogenates were decreased after 2 h of irradiation: the superoxide dismutase (SOD) activity (control value, 181 +/- 10 U SOD (g tissue)-1) was decreased by 40% and the catalase activity (control value, 1.34 +/- 0.14 pmol (g tissue)-1) was decreased by 45%. In vivo chemiluminescence appears to be a suitable method for following the kinetics of the oxidative stress processes and for testing the effect of topical application with antioxidant and photoprotective agents.
Ascorbic acid can recycle alpha-tocopherol from the tocopheroxyl free radical in lipid bilayers and in micelles, but such recycling has not been demonstrated to occur across cell membranes. In this work the ability of intracellular ascorbate to protect and to recycle alpha-tocopherol in intact human erythrocytes and erythrocyte ghosts was investigated. In erythrocytes that were 80% depleted of intracellular ascorbate by treatment with the nitroxide Tempol, both 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and ferricyanide oxidized alpha-tocopherol to a greater extent than in cells not depleted of ascorbate. In contrast, in erythrocytes in which the intracellular ascorbate concentration had been increased by loading with dehydroascorbate, loss of alpha-tocopherol was less with both oxidants than in control cells. Protection against AAPH-induced oxidation of alpha-tocopherol was not prevented by extracellular ascorbate oxidase, indicating that the protection was due to intracellular and not to extracellular ascorbate. Incubation of erythrocytes with lecithin liposomes also generated an oxidant stress, which caused lipid peroxidation in the liposomes and depleted erythrocyte alpha-tocopherol, leading to hemolysis. Ascorbate loading of the erythrocytes delayed liposome oxidation and decreased loss of alpha-tocopherol from both cells and from alpha-tocopherol-loaded liposomes. When erythrocyte ghosts were resealed to contain ascorbate and challenged with free radicals generated by AAPH outside the ghosts, intravesicular ascorbate was totally depleted over 1 h of incubation, whereas alpha-tocopherol decreased only after ascorbate was substantially oxidized. These results suggest that ascorbate within the erythrocyte protects alpha-tocopherol in the cell membrane by a direct recycling mechanism.
Photoprotective effects of topically applied antioxidants when applied before ultraviolet radiation (UVR) exposure are well known. Their protective effect when applied after UVR exposure is, however, less established.
In a randomized, double-blinded, placebo-controlled human study the short-term photoprotective effects of different antioxidants and of their combinations were evaluated when applied after UVR exposure.
Melatonin (N-acetyl-5-methoxytryptamine), vitamin E (alpha-tocopherol) and vitamin C (ascorbic acid) were topically administered alone or in combination following UVR exposure as single applications (immediately or 30 min after irradiation, respectively) or as multiple applications (three times: 30 min, 1 h and 2 h after irradiation). The erythemal reaction was evaluated visually and noninvasively with bioengineering methods (skin color and skin blood flow).
No significant protective effect of melatonin or the vitamins when applied alone or in combination were obtained when antioxidants were applied after UVR exposure. No improved photoprotective effect was obtained when multiple applications were done.
UVR-induced skin damage is a rapid event, and antioxidants possibly prevent such damage only when present in relevant concentration at the site of action beginning and during oxidative stress.
To determine the efficacy of topical ascorbic acid application in treating mild to moderate photodamage of facial skin using an objective, computer-assisted image analysis of skin surface topography and subjective clinical, photographic, and patient self-appraisal questionnaires.
A 3-month, randomized, double-blind, vehicle-controlled study.
Facial plastic surgery private practice.
Nineteen evaluable volunteer sample patients aged between 36 and 72 years with Fitzpatrick skin types I, II, and III who were in good physical and mental health with mild to moderately photodamaged facial skin were considered for analysis.
Coded, unmarked medications were randomly assigned to the left and right sides of each subject's face, one containing the active agent, topical ascorbic acid (Cellex-C high-potency serum; Cellex-C International, Toronto, Ontario), the other, the vehicle serum (Cellex-C International). Three drops (0.5 mL) of each formulation were applied daily to the randomly assigned hemifaces over the 3-month study period. Treatment assignments were not disclosed to subjects, clinicians, or personnel involved in analyzing skin replicas.
Specific clinical parameters were evaluated and graded on a 0- to 9-point scale (0, none; 1-3, mild; 4-6, moderate; and 7-9, severe). Reference photographs were used to standardize grading criteria. Overall investigator scores were compared with baseline and graded as excellent (much improved), good (improved), fair (slightly improved), no change, or worse. Patient self-appraisal questionnaires rated the degree of improvement (much improved, improved, slightly improved, no change, or worse) and reported adverse effects (burning, stinging, redness, peeling, dryness, discoloration, itching, and rash). Standard photographs were taken at baseline, including anteroposterior and left and right oblique views to facilitate subsequent clinical evaluations, and at the end of therapy for comparison. Optical profilometry analysis was performed on the skin surface replicas of the lateral canthal (crow's feet) region, comparing baseline to end-of-study specimens. Using this computer-based system, the resulting image was digitally analyzed, and numeric values were assigned to reflect surface features. The parameters obtained included Rz, Ra, and shadows. These values provided objective data that document pretreatment and posttreatment texture changes proportional to the degree of wrinkling, roughness, and other surface irregularities.
Optical profilometry image analysis demonstrated a statistically significant 73.7% improvement in the Ra and shadows north-south facial axis values with active treatment greater than vehicle control, as well as a trend for improvement in the Rz north-south facial axis parameter, showing a 68.4% greater improvement of active treatment vs vehicle control. Clinical assessment demonstrated significant improvement with active treatment greater than control for fine wrinkling, tactile roughness, coarse rhytids, skin laxity/tone, sallowness/yellowing, and overall features. Patient questionnaire results demonstrated statistically significant improvement overall, active treatment 84.2% greater than control. Photographic assessment demonstrated significant improvement, active treatment 57.9% greater than control.
A 3-month daily regimen of topical ascorbic acid provided objective and subjective improvement in photodamaged facial skin. Skin replica optical profilometry is an objective method for quantification of the skin surface texture changes.
Chronic photodamage of the skin manifests itself as extrinsic skin ageing (photoageing) and photocarcinogenesis. DNA photodamage and UV-generated reactive oxygen species are the initial molecular events that lead to most of the typical histological and clinical manifestations of chronic photodamage of the skin. Knowledge of the UV-absorbing chromophores in the skin and of the molecular mechanisms leading to the unwanted effects of sun exposure provide a basis for the development of novel strategies for the prevention and repair of photoageing. This review provides an overview of the photochemistry of the major skin chromophores and their relationship to chronic photodamage.
Aging of the population, in particular the "baby boomers," has resulted in increased interest in methods of reversal of photodamage. Non-invasive treatments are in high demand, and our knowledge of mechanisms of photodamage to skin, protection of the skin, and repair of photodamage are becoming more sophisticated and complex.
The objective of this study is to determine if the topical use of a vitamin C preparation can stimulate the skin to repair photodamage and result in clinically visible differences, as well as microscopically visible improvement.
Ten patients applied in a double-blind manner a newly formulated vitamin C complex having 10% ascorbic acid (water soluble) and 7% tetrahexyldecyl ascorbate (lipid soluble) in an anhydrous polysilicone gel base to one-half of the face and the inactive polysilicone gel base to the opposite side. Clincial evaluation of wrinkling, pigmentation, inflammation, and hydration was performed prior to the study and at weeks 4, 8, and 12. Two mm punch biopsies of the lateral cheeks were performed at 12 weeks in four patients and stained with hematoxylin and eosin, as well as in situ hybridization studies using an anti-sense probe for mRNA for type I collagen. A questionnaire was also completed by each patient.
A statistically significant improvement of the vitamin C-treated side was seen in the decreased photoaging scores of the cheeks (P = 0.006) and the peri-oral area (P = 0.01). The peri-orbital area improved bilaterally, probably indicating improved hydration. The overall facial improvement of the vitamin C side was statistically significant (P = 0.01). Biopsies showed increased Grenz zone collagen, as well as increased staining for mRNA for type I collagen. No patients were found to have any evidence of inflammation. Hydration was improved bilaterally. Four patients felt that the vitamin C-treated side improved unilaterally. No patient felt the placebo side showed unilateral improvement.
This formulation of vitamin C results in clinically visible and statistically significant improvement in wrinkling when used topically for 12 weeks. This clinical improvement correlates with biopsy evidence of new collagen formation.
Extracellular stimuli signal for activation of the transcription factor NFkappaB, leading to gene expression regulating processes involved in immune responses, inflammation, and cell survival. Tumor necrosis factor-alpha (TNFalpha) activates NFkappaB via a well-defined kinase pathways involving NFkappaB-inducing kinase (NIK), which activates downstream multisubunit IkappaB kinases (IKK). IKK in turn phosphorylates IkappaB, the central regulator of NFkappaB function. We found that intracellular vitamin C inhibits TNFalpha-induced activation of NFkappaB in human cell lines (HeLa, monocytic U937, myeloid leukemia HL-60, and breast MCF7) and primary endothelial cells (HUVEC) in a dose-dependent manner. Vitamin C is an important antioxidant, and most cells accumulate ascorbic acid (AA) intracellularly by transporting the oxidized form of the vitamin, dehydroascorbic acid (DHA). Because ascorbic acid is a strong pro-oxidant in the presence of transition metals in vitro, we loaded cells with vitamin C by incubating them with DHA. Vitamin C-loaded cells showed significantly decreased TNFalpha-induced nuclear translocation of NFkappaB, NFkappaB-dependent reporter transcription, and IkappaBalpha phosphorylation. Our data point to a mechanism of vitamin C suppression of NFkappaB activation by inhibiting TNFalpha-induced activation of NIK and IKKbeta kinases independent of p38 MAP kinase. These results suggest that intracellular vitamin C can influence inflammatory, neoplastic, and apoptotic processes via inhibition of NFkappaB activation.
Human skin, like all other organs, undergoes chronological aging. In addition, unlike other organs, skin is in direct contact with the environment and therefore undergoes aging as a consequence of environmental damage. The primary environmental factor that causes human skin aging is UV irradiation from the sun. This sun-induced skin aging (photoaging), like chronological aging, is a cumulative process. However, unlike chronological aging, which depends on the passage of time per se, photoaging depends primarily on the degree of sun exposure and skin pigment. Individuals who have outdoor lifestyles, live in sunny climates, and are lightly pigmented will experience the greatest degree of photoaging. During the last decade, substantial progress has been made in understanding cellular and molecular mechanisms that bring about chronological aging and photoaging. This emerging information reveals that chronological aging and photoaging share fundamental molecular pathways. These new insights regarding convergence of the molecular basis of chronological aging and photoaging provide exciting new opportunities for the development of new anti-aging therapies. This article reviews our current understanding and presents new data about the molecular pathways that mediate skin damage by UV irradiation and by the passage of time.
Vitamin C is known for its antioxidant potential and activity in the collagen biosynthetic pathway. Photoprotective properties of topically applied vitamin C have also been demonstrated, placing this molecule as a potential candidate for use in the prevention and treatment of skin ageing.
A topically applied cream containing 5% vitamin C and its excipient were tested on healthy female volunteers presenting with photoaged skin on their low-neck and arms in view to evaluate efficacy and safety of such treatment. A double-blind, randomized trial was performed over a 6-month period, comparing the action of the vitamin C cream vs. excipient on photoaged skin. Clinical assessments included evaluation at the beginning and after 3 and 6 months of daily treatment. They were performed by the investigator and compared with the volunteer self assessment. Skin relief parameters were determined on silicone rubber replicas performed at the same time-points. Cutaneous biopsies were obtained at the end of the trial and investigated using immunohistochemistry and electron microscopy. Clinical examination by a dermatologist as well as self-assessment by the volunteers disclosed a significant improvement, in terms of the ‘global score’, on the vitamin C-treated side compared with the control. A highly significant increase in the density of skin microrelief and a decrease of the deep furrows were demonstrated. Ultrastructural evidence of the elastic tissue repair was also obtained and well corroborated the favorable results of the clinical and skin surface examinations.
Topical application of 5% vitamin C cream was an effective and well-tolerated treatment. It led to a clinically apparent improvement of the photodamaged skin and induced modifications of skin relief and ultrastructure, suggesting a positive influence of topical vitamin C on parameters characteristic for sun-induced skin ageing.
The objective of this study was to evaluate the ability of lasers and microdermabrasion, both of which are skin resurfacing modalities, to enhance and control the in vitro skin permeation and deposition of vitamin C. The topical delivery of magnesium ascorbyl phosphate, the pro-drug of vitamin C, was also examined in this study. All resurfacing techniques evaluated produced significant increases in the topical delivery of vitamin C across and/or into the skin. The erbium:yttrium-aluminum-garnet (Er:YAG) laser showed the greatest enhancement of skin permeation of vitamin C among the modalities tested. The laser fluence and spot size were found to play important parts in controlling drug absorption. An excellent correlation was observed in the Er:YAG laser fluence and transepidermal water loss, which is an estimation of skin disruption. Permeation of magnesium ascorbyl phosphate was not enhanced by the Er:YAG laser. The CO2 laser at a lower fluence promoted vitamin C permeation with no ablation of the stratum corneum or epidermal layers. Further enhancement was observed with the CO2 laser at higher fluences, which was accompanied by a prominent ablation effect. Microdermabrasion ablated the stratum corneum layers with minimal disruption of the skin barrier properties according to transepidermal water loss levels. The flux and skin deposition of vitamin C across microdermabrasion-treated skin was approximately 20-fold higher than that across intact skin. The techniques used in this study may be useful for basic and clinical investigations of enhancement of topical vitamin C delivery.
Clinical evaluation of topical sodium l-ascorbyl-2-phosphate lotion (5%W/V) in patients with acne
- Ikeno
Ikeno J, Nishikawa T. Clinical evaluation of topical sodium L-ascorbyl-2-phosphate lotion (5%W/V) in patients with acne. Presented at the Society for Investigative Dermatology 3rd Annual Meeting; 2002 May
Topical vitamin C ester (ascorbyl palmitate)
- Perricone
Perricone NV. Topical vitamin C ester (ascorbyl palmitate). J Geriatr Dermatol 1997;5:162–70.