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Blue light-induced oxidative stress in live skin
Abstract and Figures
Skin damage from exposure to sunlight induces aging-like changes in appearance and is attributed to the ultraviolet (UV) component of light. Photosensitized production of reactive oxygen species (ROS) by UVA light is widely accepted to contribute to skin damage and carcinogenesis, but visible light is thought not to do so. Using mice expressing redox-sensitive GFP to detect ROS, blue light could produce oxidative stress in live skin. Blue light induced oxidative stress preferentially in mitochondria, but green, red, far red or infrared light did not. Blue light-induced oxidative stress was also detected in cultured human keratinocytes, but the per photon efficacy was only 25% of UVA in human keratinocyte mitochondria, compared to 68% of UVA in mouse skin. Skin autofluorescence was reduced by blue light, suggesting flavins are the photosensitizer. Exposing human skin to the blue light contained in sunlight depressed flavin autofluorescence, demonstrating that the visible component of sunlight has a physiologically significant effect on human skin. The ROS produced by blue light is probably superoxide, but not singlet oxygen. These results suggest that blue light contributes to skin aging similar to UVA.
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... Their development is the result of recent research into the effects of high energy visible radiation (HEVR), which causes skin hyperpigmentation as well as oxidative stress, immunomodulation, altered hydration levels, and even damage to cellular DNA. [6,[28][29][30][31][32] HEVR corresponds to wavelengths above 380 nm, including blue light wavelengths up to 450 nm. In 2021, a UVA1-type filter called methoxypropylamino cyclohexenylidene ethoxyethylcyanoacetate (MCE) appeared on the list of EU-approved sunscreens. ...
Topical sunscreen application is one of the most important photoprotection tool to prevent sun damaging effects in human skin at the short and long term. Although its efficacy and cosmeticity have significantly improved in recent years, a better understanding of the biological and clinical effects of longer wavelength radiation, such as long ultraviolet A (UVA I) and blue light, has driven scientists and companies to search for effective and safe filters and substances to protect against these newly identified forms of radiation. New technologies have sought to imbue sunscreen with novel properties, such as the reduction of calorific radiation. Cutaneous penetration by sunscreens can also be reduced using hydrogels or nanocrystals that envelop the filters, or by binding filters to nanocarriers such as alginate microparticles, cyclodextrins, and methacrylate polymers. Finally, researchers have looked to nature as a source of healthier products, such as plant products (e.g., mycosporines, scytonemin, and various flavonoids) and even fungal and bacterial melanin, which could potentially be used as substitutes or enhancers of current filters.
Graphical abstract
... The most relevant extrinsic factors are ultraviolet radiation (UV), infrared (IR), visible light, blue light, alcohol consumption and cigarette smoke; they all have a cumulative effect on the skin. It becomes leathery, drier, showing signs of hyperpigmentation and deep wrinkles [30][31][32][33][34][35][36][37]. These factors are involved in the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS), which cause lipid peroxidation, damage to desoxiribonucleic acid (DNA), degradation of the extracellular matrix, protein damage and glycation, also generating an inflammatory response of the skin, which triggers the immune response and causes additional oxidative stress that increases the damage [38][39][40]. ...
Currently, in addition to the use of olive oil in cosmetics, the use of olive-derived bioactives and their incorporation into cosmetics is a growing trend. The olive oil industry produces vast quantities of by-products, such as olive mill wastewater, olive pomace and leaves from which new ingredients may be obtained for cosmetic use. In this way, by-products are revalorized, which contributes to the implementation of a sustainable economy or upcycling. This review intends to provide a detailed overview of the different extraction techniques reported in order to obtain the bioactive compounds of cosmetic value that can be found in olive by-products: fatty acids, tocopherols, polyphenols, phytosterols and squalene. Different extraction techniques are presented, including some traditional techniques (solid–liquid extraction) and more novel or “greener” ones: ultrasound, microwave, supercritical extraction, pressurized fluids and deep eutectic solvents. Additionally, different applications of olive by-products in skin care products are explored: emollient, antioxidant, anti-age, anti-inflammatory, antiviral, antifungal and antibacterial, and the perspective of consumers is also considered since they increasingly demand products formulated with natural ingredients.
... Such observed antioxidant properties prompted researchers to further investigate the effects of astaxanthin on humans with a main focus on its eventual photoprotective effect, being the oxidative stress one of the main mechanisms involved in UV-induced skin damage [93]. In particular, the authors of a randomized, double-blind, placebo-controlled trial found that dietary supplementation with astaxanthin enhanced the minimal erythemal dose and reduced the dryness caused by UV rays in healthy human skin [94]. ...
Non-melanoma skin cancers (NMSCs), which include basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and actinic keratosis (AK), are the most common cancer diseases in the Caucasian race. If diagnosed late and improperly treated, BCC and SCC can become locally advanced and metastasize. Malignant melanoma (MM) is less frequent but more lethal than NMSC. Given the individual and social burdens of skin cancers, performing an adequate prevention is needed. Ultraviolet (UV) ray exposure is one of the main risk factors for skin cancer. Thus, the first-choice prevention strategy is represented by photoprotection that can be both topical and systemic. The latter consists of the oral administration of molecules which protect human skin against the damaging effects of UV rays, acting through antioxidant, anti-inflammatory, or immunomodulator mechanisms. Although several compounds are commonly used for photoprotection, only a few molecules have demonstrated their effectiveness in clinical trials and have been included in international guidelines for NMSC prevention (i.e., nicotinamide and retinoids). Moreover, none of them have been demonstrated as able to prevent MM. Clinical and preclinical data regarding the most common compounds used for systemic photoprotection are reported in this review, with a focus on the main mechanisms involved in their photoprotective properties.
... Blue light irradiation induces oxidative stress due to the accumulation of ROS produced. [29] This is due to cytochrome c oxidase, a biological fluorophore in the mitochondria, that produces ROS when affected by blue light. [30] Subsequently, the increased ROS production also significantly increases caspase-3/7 activity, which later induces cell apoptosis. ...
Background
Overexposure to sunlight can have many harmful biological effects on the skin, leading to skin cancer and photoaging. As ultraviolet (UV) radiation has been identified as a cause of DNA damage and oxidative stress in the skin, the photoprotection provided by sunscreens is evaluated through their ability to filter UV light, using the sun protection factor (SPF). However, recent data have shown that high‐energy visible (HEV) light can also cause biological skin damage.
Objectives
To develop a new in vivo method for evaluating the protection provided by sunscreens across a broad range of wavelengths, including the HEV band, based on multispectral image analysis.
Methods
This study evaluated the absorption properties of six commercially available sunscreens (five SPF 50+ products containing organic UV filters, and one product containing the wide spectrum filter, phenylene bis‐diphenyltriazine [TriAsorB™]) and of a control product containing no filter. Multispectral images were acquired from the skin on the forearms of healthy volunteers, before and after application of the test products. Images taken with LEDs emitting light at wavelengths ranging from UV to infrared were used to generate light reflectance maps for each product. The levels of absorbance of light in the UV and visible bands were then calculated.
Results
The product containing the wide spectrum filter exhibited significantly higher absorbance over the HEV band (380–450 nm) than the control product and the other commercial sunscreens. All the sunscreens tested showed the same level of absorbance at 365 nm (UVA).
Conclusions
Multispectral imaging provides a simple and reliable in vivo method for assessing the real‐world protection provided by sunscreens against all forms of photo‐induced skin damage, including that induced by HEV radiation.
Blue light includes rays of lower energy in comparison to UV radiation, but it has a greater power of penetrating the dermis, even to a depth of 1mm. The aim of this review article was to analyze the biological effects of natural and artificial blue light on the skin based on the available literature, as well as to propose preventive measures in order to protect the skin from its harmful effects. The latest research has shown that blue light has various direct and indirect effects on the skin. The direct effects of blue light on the skin are the excessive creation of reactive oxygen species, nitrogen and hyperpigmentation, and it indirectly affects the skin by disrupting the circadian rhythm and secreting melatonin. Blue light has a direct effect on chromophores that are present in the skin and leads to their activation. Their activation leads to the excessive production of reactive oxygen species and release of reactive nitrogen species, that is, nitrogen monoxide (NO), which triggers melanogenesis and hyperpigmentation. Also, there comes to the decrease in cell vitality and/or proliferation of keratinocytes and melanocytes, then increased synthesis of pro-inflammatory interleukins and tumor necrosis factor alpha and altered collagen metabolism. Blue light reduces the antioxidative protection of the skin by causing the degradation of present carotenoids. It can be used in clinical practice in the prevention and treatment of certain dermatoses, as well as in photorejuvenation treatments in aesthetic medicine. Further research in this field is necessary.
Purpose: This study aimed to extract phyto DNA from the adventitious root of Aloe vera and confirm its role in improving and regenerating skin and antiaging properties caused by blue light.Methods: Phyto DNA was extracted and a complex containing polylysine and Poly (amidoamine) was made. The antioxidant activity was confirmed using the DPPH method. The MTT test was performed on fibroblasts. The expression of SOD1 , FLG , LOR , COL1A1 , and MMP1 was measured using RT–PCR after blue light irradiation on HaCaT cells. The wound-healing test was performed. A phyto DNA complex cream formulation was created. Using this method, skin epidermal water loss was determined after human application.Results: At 0.85% of the cation polymer–phyto DNA complex concentration, 100% of fibroblasts survived. At 0.1% concentration, the antioxidant effect was 93%. After being exposed to blue light, only 40.4% of fibroblasts survived, but after being treated with a 100 μg/mL complex, 80.5% survived. At a mineral–cation-phyto DNA complex ratio of 10:1, the expression of skin barrier factors was highest. About 95.7% of HaCaT cells regenerated at 10:1 ratio of the mineral with phyto DNA complex in comparison to complex with only the minerals without phyto DNA.Conclusion: Phyto DNA from aloe vera’s adventitious root has no cytotoxicity, has excellent DPPH free radical scavenging ability, and can mitigate blue light cytotoxicity. It can improve skin barrier function by increasing the expression of barrier factors via a synergistic action in a specific ratio composition of phyto DNA, cationic polymer, and mineral complexes.
Background:
Studies indicate that blue light (BL) irradiation can damage human skins, but the impact of BL irradiation on skin aging is unknown.
Objectives:
This study aimed to give an insight to phenotypic characteristics and molecular mechanism of blue light-induced skin aging, and thus provide a theoretical basis for the precise protection of photodermatosis.
Methods:
The effect of BL on skin photoaging in mice was evaluated by non-invasive measurement equipment and histopathology analysis. The effect of BL irradiation on the proliferation of HFF-1 cells was detected by the Real-Time Cell Analyzer. The expression and protein levels of genes associated with skin aging were examined.
Results:
Our studies indicated photoaging caused by BL irradiation, including collagen disorder and increased MMP1. BL irradiation also inhibited cell proliferation and collagen expression in human skin fibroblasts by inhibiting TGF-β signaling pathway, based on in vitro experiments. Importantly, BL irradiation promoted the degradation of collagen by increasing MMP1 activated by the JNK/c-Jun and EGFR pathways. Moreover, ROS levels were significantly increased after BL irradiation in human skin fibroblasts. Yet, the transcriptional change in human skin fibroblasts caused by BL irradiation was unable to be completely restored by ROS scavenger.
Conclusion:
BL irradiation down-regulated expression of type I collagen genes and up-regulated MMP1 expression to inhibit the proliferation of human skin fibroblasts. Multiple key pathways including TGF-β, JNK, and EGFR signaling were involved in BL-induced skin aging. Our results provide theoretical bases for the protection of photoaging caused by BL irradiation.
The increase in air pollution worldwide represents an environmental risk factor that has global implications for the health of humans worldwide. The skin of billions of people is exposed to a mixture of harmful air pollutants, which can affect its physiology and are responsible for cutane-ous damage. Some polycyclic aromatic hydrocarbons are photoreactive and could be activated by ultraviolet radiation (UVR). Therefore, such UVR exposure would enhance their deleterious effects on the skin. Air pollution also affects vitamin D synthesis by reducing UVB radiation, which is essential for the production of vitamin D3, tachysterol, and lumisterol derivatives. Ambient air pollutants , photopollution, blue-light pollution, and cigarette smoke compromise cutaneous structural integrity, can interact with human skin microbiota, and trigger or exacerbate a range of skin diseases through various mechanisms. Generally, air pollution elicits an oxidative stress response on the skin that can activate the inflammatory responses. The aryl hydrocarbon receptor (AhR) can act as a sensor for small molecules such as air pollutants and plays a crucial role in responses to (photo)pollu-tion. On the other hand, targeting AhR/Nrf2 is emerging as a novel treatment option for air pollutants that induce or exacerbate inflammatory skin diseases. Therefore, AhR with downstream regulatory pathways would represent a crucial signaling system regulating the skin phenotype in a Yin and Yang fashion defined by the chemical nature of the activating factor and the cellular and tissue context.
Genetically encoded probes based on the H2O2-sensing proteins OxyR and Orp1 have greatly increased the ability to detect elevated H2O2 levels in stimulated or stressed cells. However, these proteins are not sensitive enough to monitor metabolic H2O2 baseline levels. Using yeast as a platform for probe development, we developed two peroxiredoxin-based H2O2 probes, roGFP2-Tsa2ΔCR and roGFP2-Tsa2ΔCPΔCR, that afford such sensitivity. These probes are ∼50% oxidized under 'normal' unstressed conditions and are equally responsive to increases and decreases in H2O2. Hence, they permit fully dynamic, real-time measurement of basal H2O2 levels, with subcellular resolution, in living cells. We demonstrate that expression of these probes does not alter endogenous H2O2 homeostasis. The roGFP2-Tsa2ΔCR probe revealed real-time interplay between basal H2O2 levels and partial oxygen pressure. Furthermore, it exposed asymmetry in H2O2 trafficking between the cytosol and mitochondrial matrix and a strong correlation between matrix H2O2 levels and cellular growth rate.
Background:
Observational and experimental data suggest that antioxidant and/or zinc supplements may delay progression of age-related macular degeneration (AMD) and vision loss.
Objective:
To evaluate the effect of high-dose vitamins C and E, beta carotene, and zinc supplements on AMD progression and visual acuity.
Design:
The Age-Related Eye Disease Study, an 11-center double-masked clinical trial, enrolled participants in an AMD trial if they had extensive small drusen, intermediate drusen, large drusen, noncentral geographic atrophy, or pigment abnormalities in 1 or both eyes, or advanced AMD or vision loss due to AMD in 1 eye. At least 1 eye had best-corrected visual acuity of 20/32 or better. Participants were randomly assigned to receive daily oral tablets containing: (1) antioxidants (vitamin C, 500 mg; vitamin E, 400 IU; and beta carotene, 15 mg); (2) zinc, 80 mg, as zinc oxide and copper, 2 mg, as cupric oxide; (3) antioxidants plus zinc; or (4) placebo.
Main outcome measures:
(1) Photographic assessment of progression to or treatment for advanced AMD and (2) at least moderate visual acuity loss from baseline (> or =15 letters). Primary analyses used repeated-measures logistic regression with a significance level of.01, unadjusted for covariates. Serum level measurements, medical histories, and mortality rates were used for safety monitoring.
Results:
Average follow-up of the 3640 enrolled study participants, aged 55-80 years, was 6.3 years, with 2.4% lost to follow-up. Comparison with placebo demonstrated a statistically significant odds reduction for the development of advanced AMD with antioxidants plus zinc (odds ratio [OR], 0.72; 99% confidence interval [CI], 0.52-0.98). The ORs for zinc alone and antioxidants alone are 0.75 (99% CI, 0.55-1.03) and 0.80 (99% CI, 0.59-1.09), respectively. Participants with extensive small drusen, nonextensive intermediate size drusen, or pigment abnormalities had only a 1.3% 5-year probability of progression to advanced AMD. Odds reduction estimates increased when these 1063 participants were excluded (antioxidants plus zinc: OR, 0.66; 99% CI, 0.47-0.91; zinc: OR, 0.71; 99% CI, 0.52-0.99; antioxidants: OR, 0.76; 99% CI, 0.55-1.05). Both zinc and antioxidants plus zinc significantly reduced the odds of developing advanced AMD in this higher-risk group. The only statistically significant reduction in rates of at least moderate visual acuity loss occurred in persons assigned to receive antioxidants plus zinc (OR, 0.73; 99% CI, 0.54-0.99). No statistically significant serious adverse effect was associated with any of the formulations.
Conclusions:
Persons older than 55 years should have dilated eye examinations to determine their risk of developing advanced AMD. Those with extensive intermediate size drusen, at least 1 large druse, noncentral geographic atrophy in 1 or both eyes, or advanced AMD or vision loss due to AMD in 1 eye, and without contraindications such as smoking, should consider taking a supplement of antioxidants plus zinc such as that used in this study.
Fluorescent protein sensors have re-vitalized the field of redox biology by revolutionizing the study of redox processes in living cells and organisms. Recent Advances: Within one decade a set of fundamental new insights has been gained, driven by the rapid technical development of in vivo redox sensing. Redox-sensitive yellow and green fluorescent protein variants (rxYFP and roGFPs) have been the central players.
Although widely used as an established standard tool, important questions remain surrounding their meaningful use in vivo. We review the growing range of thiol redox sensor variants and their application in different cells, tissues and organisms. We highlight five key findings where in vivo sensing has been instrumental in changing our understanding of redox biology, critically assess the interpretation of in vivo redox data and discuss technical and biological limitations of current redox sensors and sensing approaches.
We explore how novel sensor variants may further add to the current momentum towards a novel mechanistic and integrated understanding of redox biology in vivo.
Mutations in sunlight-induced melanoma arise from cyclobutane pyrimidine dimers (CPDs), DNA photoproducts that are typically created picoseconds after an ultraviolet (UV) photon is absorbed at thymine or cytosine. We found that in melanocytes, CPDs are generated for >3 hours after exposure to UVA, a major component of the radiation in sunlight and in tanning beds. These "dark CPDs" constitute the majority of CPDs and include the cytosine-containing CPDs that initiate UV-signature C→T mutations. Dark CPDs arise when UV-induced reactive oxygen and nitrogen species combine to excite an electron in fragments of the pigment melanin. This creates a quantum triplet state that has the energy of a UV photon but induces CPDs by energy transfer to DNA in a radiation-independent manner. Melanin may thus be carcinogenic as well as protective against cancer. These findings also validate the long-standing suggestion that chemically generated excited electronic states are relevant to mammalian biology.
Copyright © 2015, American Association for the Advancement of Science.
Most of us know there is a payoff to looking good, and in the quest for beauty we spend countless hours and billions of dollars on personal grooming, cosmetics, and plastic surgery. But how much better off are the better looking? Based on the evidence, quite a lot. The first book to seriously measure the advantages of beauty,Beauty Paysdemonstrates how society favors the beautiful and how better-looking people experience startling but undeniable benefits in all aspects of life. Noted economist Daniel Hamermesh shows that the attractive are more likely to be employed, work more productively and profitably, receive more substantial pay, obtain loan approvals, negotiate loans with better terms, and have more handsome and highly educated spouses. Hamermesh explains why this happens and what it means for the beautiful--and the not-so-beautiful--among us. Exploring whether a universal beauty standard exists, Hamermesh illustrates how attractive workers make more money, how these amounts differ by gender, and how looks are valued differently based on profession. The author wonders whether extra pay for good-looking people represents discrimination, and, if so, who is discriminating. He investigates the commodification of beauty in dating and how this influences the search for intelligent or high-earning mates, and even considers whether government programs should aid the ugly. Hamermesh also discusses whether the economic benefits of beauty will persist into the foreseeable future and what the "looks-challenged" can do to overcome their disadvantage. © Daniel S. Hamermesh Princeton University Press. All Rights Reserved.
The photochemical aspects of flavins have been reviewed with reference to the analysis of flavins and photoproducts in degraded solutions, spectral and photophysical properties, photodegradation reactions, photosensitization reactions, and photostability of riboflavin in pharmaceutical preparations. The photochemistry of flavins in aqueous solution involves two major photodegradation reactions, viz intramolecular photoreduction and photoaddition, occurring separately or concomitantly in the presence of phosphate buffer, leading to the formation of lumichrome and cyclodehydroriboflavin, respectively. The photoreduction is catalyzed by H2PO4- ions and the photoaddition by HPO42− ions. Intermolecular photoreduction also takes place in a large number of flavin-substrate interactions involving the flavin triplet state. Knowledge of the spectral and photophysical properties, and photochemical behaviour of flavins is necessary to understand the nature of flavin–protein interactions, flavin photosensitization reactions, and their role in biological processes. The study of the photochemical behaviour of riboflavin as a function of pH is a prerequisite to achieve optimum stability of the vitamin in pharmaceutical preparations. Technological processes are being developed to utilize riboflavin as a photosensitizer in the pathogenic inactivation of blood components. Riboflavin-sensitized photooxidation of amino acids in protein may have important biological implications to control photoinduced damage in biological systems. The application of femtosecond-resolved fluorescence spectroscopy and transient absorption techniques may provide useful information on the dynamics of flavoproteins.
Integrity of human skin is endangered by exposure to UV irradiation and chemical stressors, which can provoke a toxic production of reactive oxygen species (ROS) and oxidative damage. Since oxidation of proteins and metabolites occurs virtually instantaneously, immediate cellular countermeasures are pivotal to mitigate the negative implications of acute oxidative stress. We investigated the short-term metabolic response in human skin fibroblasts and keratinocytes to H2O2 and UV exposure. In time-resolved metabolomics experiments, we observed that within seconds after stress induction, glucose catabolism is routed to the oxidative pentose phosphate pathway (PPP) and nucleotide synthesis independent of previously postulated blocks in glycolysis (i.e., of GAPDH or PKM2). Through ultra-short (13)C labeling experiments, we provide evidence for multiple cycling of carbon backbones in the oxidative PPP, potentially maximizing NADPH reduction. The identified metabolic rerouting in oxidative and non-oxidative PPP has important physiological roles in stabilization of the redox balance and ROS clearance.
Copyright © 2015 Elsevier Inc. All rights reserved.
DNA damage induced by UV radiation and visible light (290-500 nm) in AS52 Chinese hamster cells was analysed by an alkaline elution assay with specific repair endonucleases. Cells were exposed to extensively filtered monochrome or broad-band radiation. Between 290 and 315 nm, the ratio of base modifications sensitive to Fpg protein (i.e. 8-hydroxyguanine and formamidopyrimidines) and T4 endonuclease V (i.e. cyclobutane pyrimidine dimers) was constant (approximately 1:200), indicating that the direct excitation of DNA is responsible for both types of damage in this range of the spectrum. While the yield of pyrimidine dimers per unit dose continued to decrease exponentially beyond 315 nm, the yield of Fpg-sensitive modifications increased to a second maximum between 400 and 450 nm. The damage spectrum in this wavelength range consisted of only a few other modifications (strand breaks, abasic sites and pyrimidine modifications sensitive to endonuclease III) and is attributed to endogenous photosensitizers that give rise to oxidative DNA damage via singlet oxygen and/or type I reactions. The generation of Fpg-sensitive modifications by visible light was not linear with dose but followed a saturation curve. It is calculated that the exposure of the cells to low doses of solar radiation results in the formation of cyclobutane pyrimidine dimers and Fpg-sensitive modifications in a ratio of 10:1.
Description
Flavins and flavoproteins are a widely investigated and highly versatile group of compounds. Participation of these compounds in photochemistry and photobiology processes are of particular importance in the fields of biology, chemistry and medicine. Written by leading experts in the field each section of the book includes a historical overview of the subject, state of the art developments and future perspectives. Flavins: Photochemistry and Photobiology begins with the properties and applications of flavins, including their photochemistry in aqueous and organic solutions. Subsequent sections discuss riboflavin as a visible light sensitizer in the photo degradation of drugs, antiviral and antibacterial effects, the role of flavins in light induced toxicity and blue light initiated DNA repair by photolyase. Finally there are sections on the flavin based photoreceptors in plants, bacteria and eukaryotic photosynthetic flagelettes. This book brings together leading experts with a unique interdisciplinary emphasis, to provide an authoritative resource on flavins and their role in photochemistry and photobiology.