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Nutrition and aging skin: Sugar and glycation

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Abstract

The effect of sugars on aging skin is governed by the simple act of covalently cross-linking two collagen fibers, which renders both of them incapable of easy repair. Glucose and fructose link the amino acids present in the collagen and elastin that support the dermis, producing advanced glycation end products or "AGEs." This process is accelerated in all body tissues when sugar is elevated and is further stimulated by ultraviolet light in the skin. The effect on vascular, renal, retinal, coronary, and cutaneous tissues is being defined, as are methods of reducing the glycation load through careful diet and use of supplements.

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... Although its significance was not appreciated at the time, this finding demonstrated a quintessential connection between diet and skin health. We now understand that food is a source of both monosaccharides that, in high amounts, catalyze the production of AGEs in the body, and preformed AGEs [226]. ...
... TNFα, IL-6 and CRP) in diabetic human patients, as well as an improvement in wound healing and other diabetes-associated sequelae in mice [136,216]. Other authors have cited the relatively youthful appearance that is often associated with the elderly Asian population as evidence of the long-term impact of employing water-based cooking practices, which are characteristic of Asian cooking [226]. ...
... Tight glycemic control over a 4-month period can result in a reduction of glycated collagen formation by 25% [226,227]. Consumption of a low-sugar diet prepared through waterbased cooking methods would limit both the consumption of preformed exogenous AGES and endogenous production through physiological glycation. Avoiding foods that result in higher levels of AGEs, such as donuts, barbecued meats, and dark-colored soft drinks, can be an effective strategy for slowing "sugar sag" [21]. ...
Chapter
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First described in the context of diabetes, advanced glycation end products (AGEs) are formed through a type of non-enzymatic reaction called glycation. Protein glycation and formation of advanced glycation end products (AGEs) play an important role in the pathogenesis of diabetic complications like retinopathy, nephropathy, neuropathy, cardiomyopathy along with some other diseases such as rheumatoid arthritis, osteoporosis, and, recently, skin aging. Glycation of proteins interferes with their normal functions by disrupting molecular conformation, altering enzymatic activity, and interfering with receptor functioning. AGEs form intra- and extracellular cross linking not only with proteins, but with some other endogenous key molecules including lipids and nucleic acids to contribute in the development of diabetic complications. Recent studies suggest that AGEs interact with plasma membrane localized receptors for AGEs (RAGE) to alter intracellular signaling, gene expression, release of pro-inflammatory molecules and free radicals. Characteristic findings of aging skin, including decreased resistance to mechanical stress, impaired wound healing, and distorted dermal vasculature, can be in part attributable to glycation. Multiple factors mediate cutaneous senescence, and these factors are generally characterized as endogenous (e.g., telomere shortening) or exogenous (e.g., ultraviolet radiation exposure). Interestingly, AGEs exert their pathophysiological effects from both endogenous and exogenous routes. The former entails the consumption of sugar in the diet, which then covalently binds an electron from a donor molecule to form an AGE. The latter process mostly refers to the formation of AGEs through cooking. Results of several studies in animal models and humans show that the restriction of dietary AGEs has positive effects on wound healing, insulin resistance and cardiovascular diseases. Recently, the effect of restriction in AGEs intake has been reported to increase the lifespan in animal models. Recent studies have revealed that certain methods of food preparation (i.e. grilling, frying, and roasting) produce much higher levels of AGEs than water-based cooking methods such as boiling and steaming. Moreover, several dietary compounds have emerged as promising candidates for the inhibition of glycation-mediated aging. In this chapter, we summarize the evidence supporting the critical role of glycation in skin aging and highlight preliminary studies on dietary strategies that may be able to combat this process.
... Once the concentrations of glucose bonded to elastin proteins are sufficiently high, such as during old age or in diabetics, elastin begins to degrade which may cause results such as lowered elastic response. This loss of elasticity can be easily viewed as wrinkles in the skin [10,11]. Coinciding with the change of mechanical properties, the ferroelectric response of elastin is also suppressed by the increasing severity of glycation [9]. ...
... Solving these equations and using the relation given in (8)/(9) will lead to the exact same result as given by Eq. (11). There is a common parameter; (10) and (11) that cannot be estimated without some additional information about the material which is being examined. ...
... This can help us effectively find the Curie temperature for the model system. Since we know that The two-site model exhibits some unphysical behavior in the middle, which is an artifact of switching the independent and dependent variables when plotting (11). This is discussed further in the next section where we also present results from the six-site model. ...
Article
Biological tissues are soft, amorphous and often appear to possess a high degree of material symmetry. This would appear to preclude a phenomenon like ferroelectricity which, in the world of hard materials, only occurs in selected crystalline materials that are non-centrosymmetric. Recent experiments, however, indicate the presence of ferroelectricity in soft biological entities such as the protein elastin—a large biopolymer found in the extracellular domains of most tissues. In this letter, we present a model and an explanation for this intriguing observation. Based on a very simple physical hypothesis, we develop an analytical statistical mechanics model that, coupled with insights from molecular dynamics, provides a plausible mechanism underpinning biological ferroelectricity. Furthermore, we predict for the first time, piezoelectric properties of tropoelastin, a precursor/monomer of elastin—properties that are not easily obtained from experiments. Specifically we find that the piezoelectric constant of tropoelastin is larger than any known polymer.
... The satisfaction level depends on education level, tumor size, and histopathological results in the form of malignanc. 5,9 However, the authors did not find any statistically significant difference in satisfaction rate between two groups, although the purse-string technique results in a shorter length of the scar and no wrinkle observed. The authors realized that this study still has limitations. ...
... The difference between scar and wrinkles could also be caused by differences in the surgeon skills and differences in the use of surgical tools. 5,9,12 Nevertheless, these factors were not analyzed in this study. ...
... Whisker box plots showing the median scar length and width between purse string and conventional groups.The wrinkles found in two subjects (15.38%) of the conventional suture group. In the perspective of subjects' satisfaction on the esthetic findings in both groups, there was no difference between the pursestring suture group with the satisfaction rate of 9 (8-9, Likert scale) and the conventional suture group with the satisfaction rate of 9 (8-10, Likert scale).5The scars in purse string method. ...
... In the beginning of 1942, warning signs have been issued regarding the elevated amounts of sugar contained in North American diet (13). Soon after that, in 1945, Urbach and Lentz revealed the fact that a high sugar diet was associated with elevated serum and skin sugar levels and that a hypoglycemic diet lowered the skin's sugar level (14). ...
... Moreover, some of the excess sugars are bounded to proteins and this form of protein-bounded sugars are involved in the process named glycation, which results in the formation of a complex named advanced glycation end products or AGE (13). ...
... It is now current knowledge that modern food is a source of preformed AGEs and monosaccharides, which also catalyze AGE's production (13). ...
... One important mechanism proved to be involved in this connection is represented by the advanced glycation end products (AGEs), which have the ability to exert their negative effects by impacting on both intrinsic and extrinsic skin ageing mechanisms. Food is the source of sugars, which are involved in the production of AGEs but, additionally, some foods contain preformed AGEs (46), which induce changes in cutaneous collagen, elastin and fibronectin. ...
... Glucose and fructose (from diet) bond to the amino acids from collagen or elastin, leading to the production of advanced glycation end products (AGEs), process which is accelerated by hyperglycemia. Accumulation of AGEs in skin is strongly associated with increased stiffness and reduced elasticity (46). Glycation (Maillard reaction) is a non-enzymatic reaction between digested sugars (glucose, fructose) and proteins, lipids or nucleic acids (48) that leads to the formation of advanced glycation end products (AGEs). ...
Article
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Objectives: The skin is a dynamic, visible organ, showing the most obvious signs of aging. The mechanisms of extrinsic aging, most of them presented in this paper, are currently well known and also the only ones that can be counteracted. Therefore, the transition of this knowledge in the general population is of the most importance, in order to introduce healthy aging strategies, to prevent the development of chronic or malignant diseases and psychological burden related to old age. Materials and methods: A thorough review of the literature has been performed in order to identify the main factors involved in skin health and aging. Outcomes: This concept article represents a compilation of seven anti-ageing directions regarding major factors involved in health, aging and beauty, respectively sun, sugar, smoking, skin care, stress, sleep and second (the passage of time), easy to comprehend by the general public but sustained by a strong scientific documentation. Conclusions: Despite its final destination, every quality concept has to pass through academic purgatory as, once accepted, it comes to respond to ever more educated society’s demands in terms of anti-ageing.
... Glycation is an aging reaction of naturally occurring sugars and dermal proteins [46], which begins in early life, develops clinical symptoms at around 30, and progressively accumulates in tissues and skin due to the glycated collagens that are difficult to be decomposed [47]. AGEs derived from natural sugars (such as glyceraldehyde-3-PO4, glucose-6-PO4, and fructose) are formed several times faster than AGEs derived from glucose. ...
... High-sugar foods activate the reward system of hypothalamic regulation to promote the intake of more foods that are easily metabolized as glucose [49]. A correlation has been shown between a high-sugar diet and elevated sugar levels in the blood and skin, and a low-sugar diet can reduce skin sugar levels [47]. ...
Article
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Our skin is an organ with the largest contact area between the human body and the external environment. Skin aging is affected directly by both endogenous factors and exogenous factors (e.g., UV exposure). Skin saccharification, a non-enzymatic reaction between proteins, e.g., dermal collagen and naturally occurring reducing sugars, is one of the basic root causes of endogenous skin aging. During the reaction, a series of complicated glycation products produced at different reaction stages and pathways are usually collectively referred to as advanced glycation end products (AGEs). AGEs cause cellular dysfunction through the modification of intracellular molecules and accumulate in tissues with aging. AGEs are also associated with a variety of age-related diseases, such as diabetes, cardiovascular disease, renal failure (uremia), and Alzheimer’s disease. AGEs accumulate in the skin with age and are amplified through exogenous factors, e.g., ultraviolet radiation, resulting in wrinkles, loss of elasticity, dull yellowing, and other skin problems. This article focuses on the damage mechanism of glucose and its glycation products on the skin by summarizing the biochemical characteristics, compositions, as well as processes of the production and elimination of AGEs. One of the important parts of this article would be to summarize the current AGEs inhibitors to gain insight into the anti-glycation mechanism of the skin and the development of promising natural products with anti-glycation effects.
... A high-sugar diet, ultraviolet irradiation, and eating barbecued fried foods, lead to the accumulation of AGEs and acceleration of skin aging. However, strict control of blood sugar for four months can reduce the production of glycosylated collagen by 25%, and low-sugar food prepared by boiling can also reduce the production of AGEs [93][94][95]. When the mice were fed with carbohydrate-controlled diets for 50 weeks, the epidermis and dermis were significantly thinned, autophagy was inhibited, and inflammation was exacerbated. ...
... [81,82] Sugar and baked goods Associated with skin thickness, AGEs, autophagy, and inflammation. [93][94][95][96] ...
Article
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We regularly face primary challenges in deciding what to eat to maintain young and healthy skin, defining a healthy diet and the role of diet in aging. The topic that currently attracts maximum attention is ways to maintain healthy skin and delay skin aging. Skin is the primary barrier that protects the body from external aggressions. Skin aging is a complex biological process, categorized as chronological aging and photo-aging, and is affected by internal factors and external factors. With the rapid breakthrough of medicine in prolonging human life and the rapid deterioration of environmental conditions, it has become urgent to find safe and effective methods to treat skin aging. For diet, as the main way for the body to obtain energy and nutrients, people have gradually realized its importance to the skin. Therefore, in this review, we discuss the skin structure, aging manifestations, and possible mechanisms, summarize the research progress, challenges, possible directions of diet management, and effects of foodborne antioxidants on skin aging from the perspective of food and nutrition.
... Advanced glycation end (AGE) products are formed by a nonenzymatic process called glycation, during which proteins, lipids, or nucleic acids are covalently bound by sugar molecules such as glucose or fructose, resulting in the inhibition of normal function of target molecules 46 . This is quite different from normal glycosylation, which occurs at defined sites under mediation of enzymes and is necessary for target molecules to fulfill their functions. ...
... Because it's still technically infeasible to reverse glycated proteins to their original state, currently the primary strategy still stays on the prevention of proteins from glycation. But the problem is that diet provides not only sugars such as glucose and fructose but also preformed AGEs, and the latter have a large amount in grilled, fried, or roasted food but very low content in foods prepared by water-based cooking such as boiling and steaming 46 . Therefore, low-sugar food cooked with water would decrease the intake of preformed exogenous AGEs and endogenous production of physiologically glycated proteins. ...
Article
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As the most voluminous organ of the body that is exposed to the outer environment, the skin suffers from both intrinsic and extrinsic aging factors. Skin aging is characterized by features such as wrinkling, loss of elasticity, laxity, and rough-textured appearance. This aging process is accompanied with phenotypic changes in cutaneous cells as well as structural and functional changes in extracellular matrix components such as collagens and elastin. In this review, we summarize these changes in skin aging, research advances of the molecular mechanisms leading to these changes, and the treatment strategies aimed at preventing or reversing skin aging.
... As well as environmental agents, dietary factors, especially the consumption of too much sugar, are also thought to cause wrinkles [25]. The factors responsible for this are advanced glycation end-products (AGEs) that are formed when glucose and fructose bind to and crosslink collagen and elastin fibers within the dermis [26]. Cross-linking of these proteins alters skin's mechanical properties and prevents their repair following damage [25,26]. ...
... The factors responsible for this are advanced glycation end-products (AGEs) that are formed when glucose and fructose bind to and crosslink collagen and elastin fibers within the dermis [26]. Cross-linking of these proteins alters skin's mechanical properties and prevents their repair following damage [25,26]. With the inclusion of carnosine, which we have previously shown to limit AGE formation [25], NC should also reduce AGE levels. ...
Article
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Introduction: Extrinsic factors, such as solar radiation and urban pollution, cause damage that alters the structure, function and appearance of skin. The aim of this study was to determine the ability of a night cream containing melatonin, carnosine and Helichrysum italicum extract (referred to here as Night Cream) to reduce extrinsic skin damage, and to evaluate the efficacy of this Night Cream to reduce clinical signs of age and photodamage under normal conditions of use. Methods: Recovery from extrinsic damage was assessed by exposing human skin explants to ultraviolet (UV) A, infrared light, blue light or pollution and then treating the stress-exposed explants with Night Cream. Markers of oxidative stress were examined by immunohistochemistry. Anti-aging and calming properties were determined in four single-center, open-label trials involving 117 individuals. Subjects applied Night Cream to their face once nightly for up to 12 weeks. Improvements in clinical signs of age and photodamage, and reduction of lactic acid-induced stinging were evaluated by investigator assessment and subject self-assessment. Results: Night Cream significantly reduced oxidative stress in human skin ex vivo. Clinically, hydration (+ 64.4%; p < 0.05) and transepidermal water loss (TEWL) values (- 10.0%; p < 0.05) were improved within 1 h of use. Wrinkle counts were reduced by up to 18.9% (p < 0.05), and brown and UV spot numbers by 5.5% (p < 0.05) and 13.2% (p < 0.05), respectively. Lactic acid-induced stinging was significantly reduced within 7 days of use, with 86.7% of subjects reporting that their skin felt calmer. Conclusion: These findings suggest that Night Cream reduces skin damage caused by environmental factors and that its nightly use can improve clinical signs of aging with additional skin calming benefits.
... Due to its greater risk of glycation, a hyperglycemic diet is a predisposing factor for skin aging. 83 It is challenging to study this relationship because obesity and diabetes are associated in most patients. ...
Article
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Studies assessing the impact of extrinsic factors on skin aging have increased during the last with the increase in life expectancy. Although most of the studies are about the sun radiation impact, many factors should be considered in elderly people, beyond environmental conditions. Lifestyle factors, like diet, sleeping, smoking, should be analyzed carefully, as common age-related conditions (menopause, diabetes, pulmonary diseases, etc.). All these factors could accelerate the natural decline of skin structure and functions, possibly affecting the responses to treatments and drugs. This review demonstrates that growing evidence regarding environmental factors that are associated with lifestyle and comorbidities deserve greater attention from researchers and dermatologists and may require new approaches in the management of skin aging.
... AGEs banyak ditemukan pada makanan yang dipanggang, digoreng, atau dibakar, tetapi kandungan yang sangat rendah dalam makanan yang dimasak berbasis air seperti merebus dan mengukus. Oleh karena itu, makanan rendah gula yang dimasak dengan air akan menurunkan asupan AGEs eksogen yang telah terbentuk sebelumnya dan produksi endogen protein terglikasi [7], [47]. ...
Article
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Geriatric have different skin characteristic compared with they who are in young age. There is a change in both intrinsic and extrinsic aging factors causing skin aging which is marked by skin wrinkles, loss of elasticity, and textural changes. The composition of collagen in geriatrics has decreased and there is an increase in matrix metalloproteinases resulted in skin aging. These conditions together with exposure to UVR, infection, and other risk factors cause various skin problems such as xerosis cutis, decubitus ulcers, dermatophytosis, and herpes zoster. Skin problems can be prevented by changing lifestyles, using some cosmetics, medications, and having treatments. The prevention methods continues to grow and is still being researched to get optimal results and best suit skin conditions. Treatment of skin diseases in geriatrics should be carried out with caution considering the multimorbidity and immunosuppression that often occur in geriatrics. This article discusses skin differences in geriatrics, mechanisms of skin aging, common skin diseases, prevention, and safe treatment in geriatrics.
... In both in vitro experiments [70] and in vivo [71] studies, it has been shown that UV irradiation may also enhance the formation of AGEs in the skin. A diet too high in sugar (hyperglycemia) and certain methods of food preparation are also responsible for higher levels of AGEs in the skin [72]. Interestingly, a non-invasive method (AGE-Reader, DiagnOptics B.V., Groningen, The Netherlands) has been developed to measure the skin content of AGEs. ...
Article
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The relationship between oxidative stress and skin aging/disorders is well established. Many topical and oral antioxidants (vitamins C and E, carotenoids, polyphenols) have been proposed to protect the skin against the deleterious effect induced by increased reactive oxygen species production, particularly in the context of sun exposure. In this review, we focused on the combination of vitamin E and selenium taken in supplements since both molecules act in synergy either by non-enzymatic and enzymatic pathways to eliminate skin lipids peroxides, which are strongly implicated in skin and hair disorders.
... A wrinkle is a fold, ridge or crease in the skin, also known as a rhytide. The appearance of wrinkles is one of the typical sign of aging processes [23]. Different causes which can enhance wrinkle formation include, habitual sleeping positions, loss of body mass, prolonged immersion in water, habitual facial expressions, aging, sun damage, smoking, and poor hydration. ...
Article
Full-text available
Hyaluronic acid (HA) plays multifaceted role in regulating the various biological processes such as skin repairmen, diagnosis of cancer, wound healing, tissue regeneration, anti-inflammatory, and immunomodulation. Owing to its remarkable biomedical and tissue regeneration potential, HA has been numerously employed as one of the imperative components of the cosmetic and nutricosmetic products. The present review aims to summarize and critically appraise recent developments and clinical investigations on cosmetic and nutricosmetic efficacy of HA for skin rejuvenation. A thorough analysis of the literature revealed that HA based formulations (i.e., gels, creams, intra-dermal filler injections, dermal fillers, facial fillers, autologous fat gels, lotion, serum, and implants, etc.) exhibit remarkable anti-wrinkle, anti-nasolabial fold, anti-aging, space-filling, and face rejuvenating properties. This has been achieved via soft tissue augmentation, improved skin hydration, collagen and elastin stimulation, and face volume restoration. HA, alone or in combination with lidocaine and other co-agents, showed promising efficacy in skin tightness and elasticity, face rejuvenation, improving aesthetic scores, reducing the wrinkle scars, longevity, and tear trough rejuvenation. Our critical analysis evidenced that application/administration of HA exhibits outstanding nutricosmetic efficacy and thus is warranted to be used as a prime component of cosmetic products.
... Micronutrients like vitamin A, E, C, and B, iron, copper, phosphorous, manganese are the active ingredients of dietary supplements. Apart from these omega-3 fatty acids (eicosapentaenoic acid and docosahexaenoic acid), flavonoids (phytoestrogen), free radical quenching compounds like coenzyme Q10, other substances like carotenoids, lycopene, lutein, and zeaxanthin are imperative nutrient supplements as they possess antioxidant properties [8,9]. Herbs and spices like oregano, cinnamon, cloves, garlic, ginger and lipoic acids from fruits and vegetables play vital role in maintaining the normal glucose level as its higher concentration may lead to reduced elasticity and increased stiffness in skin [8,10]. ...
Chapter
Skin, known to be the largest organ, consists of epidermis and dermis. Any physiological change associated with age is ultimately reflected by a person’s skin. Two major factors responsible for premature aging are intrinsic, i.e., involvement of genes, and extrinsic that covers exposure of skin to ultraviolet (UV) radiation. UV rays induce the oxidative stress and consequently cause the loss of cellular regulation. Dietary nutriments may help the body to fight against signs of early aging as antioxidants and by regulating keratinocytes proliferation and differentiation. Main ingredients of these dietary supplements include several vitamins, minerals, phytochemicals, omega-3 fatty acids, amino acids, and probiotics. Vitamin A, C, D, and E assist in maintaining skin veracity. Zinc, copper, and selenium are the main minerals which are involved in sustenance of healthy skin. Phytochemicals consisting of flavonoids, terpenoids, and alkaloids with antibacterial, antifungal, and antioxidative property may benefit the texture and physiological parameters of skin delaying its aging. Amino acids like arginine, proline, ornithine, and glutamine alone as well as in combination support the healthy being of skin. The probiotic bacteria like Lactobacillus johnsonii and Lactobacillus plantarum commonly found in intestine aid in delaying aging by hydrating the skin as well as by showing protective effect on UV-exposed area. Though many clinical studies favor the role of dietary substances in prevention of early skin aging there is a need to cover the wider population and understand the various contributory factors.
... It induces skin aging and leads to numerous diseases (e.g. inflammation, atherosclerosis, neurodegenerative disorders, cancer) (Dandy, 2010;Fatima, Jairajpuri, & Saleemuddin, 2008). Much research is thus carried out to mitigate the MR in the human body. ...
... Skin is a multifunctional organ, serving important defense functions against external insults to the body, as both a physical barrier toward the external milieu and an immune defense against potentially pathogenic microbial forms. 1 The skin is subject to both intrinsic (chronological) and extrinsic (environmental) aging, resulting in a loss of functional capacity. 2 Wrinkle formation is a sign of accelerated aging of skin as an organ and is negatively affected by metabolic dysfunction and loss of glycemic control, 3 as well as increased blood lipids. Age-related wrinkling in the skin is promoted by habitual facial expressions, aging, sun damage, smoking, poor hydration, and various other factors. ...
Article
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Objective The aim of this study was to evaluate the effects of water-soluble egg membrane (WSEM) on wrinkle reduction in a clinical pilot study and to elucidate specific mechanisms of action using primary human immune and dermal cell-based bioassays. Methods To evaluate the effects of topical application of WSEM (8%) on human skin, an open-label 8-week study was performed involving 20 healthy females between the age of 45 years and 65 years. High-resolution photography and digital analysis were used to evaluate the wrinkle depth in the facial skin areas beside the eye (crow’s feet). WSEM was tested for total antioxidant capacity and effects on the formation of reactive oxygen species by human polymorphonuclear cells. Human keratinocytes (HaCaT cells) were used for quantitative polymerase chain reaction analysis of the antioxidant response element genes Nqo1, Gclm, Gclc, and Hmox1. Evaluation of effects on human primary dermal fibroblasts in vitro included cellular viability and production of the matrix components collagen and elastin. Results Topical use of a WSEM-containing facial cream for 8 weeks resulted in a significant reduction of wrinkle depth (P<0.05). WSEM contained antioxidants and reduced the formation of reactive oxygen species by inflammatory cells in vitro. Despite lack of a quantifiable effect on Nrf2, WSEM induced the gene expression of downstream Nqo1, Gclm, Gclc, and Hmox1 in human keratinocytes. Human dermal fibroblasts treated with WSEM produced more collagen and elastin than untreated cells or cells treated with dbcAMP control. The increase in collagen production was statistically significant (P<0.05). Conclusion The topical use of WSEM on facial skin significantly reduced the wrinkle depth. The underlying mechanisms of this effect may be related to protection from free radical damage at the cellular level and induction of several antioxidant response elements, combined with stimulation of human dermal fibroblasts to secrete high levels of matrix components.
... 41,61 The process of glycation starts quite early in life and varies according to diet and also ultraviolet exposure, which independently increases cross-linking in the skin. 62 In addition, it has been shown that in Asian populations, differences in skincare habits correspond with variations in skin parameters; subjects with the least severe photodamage reported a generally early onset of their skincare habits related to sun exposure, facial cleansing, make-up usage, and sun protection product usage. 41 ...
Article
Aging is an inevitable and complex process that can be described clinically as features of wrinkles, sunspots, uneven skin color, and sagging skin. These cutaneous effects are influenced by both intrinsic and extrinsic factors and often are varied based on ethnic origin given underlying structural and functional differences. The authors sought to provide updated information on facets of aging and how it relates to ethnic variation given innate differences in skin structure and function. Publications describing structural and functional principles of ethnic and aging skin were primarily found through a PubMed literature search and supplemented with a review of textbook chapters. The most common signs of skin aging despite skin type are dark spots, loss of elasticity, loss of volume, and rhytides. Skin of color has many characteristics that make its aging process unique. Those of Asian, Hispanic, and African American descent have distinct facial structures. Differences in the concentration of epidermal melanin makes darkly pigmented persons more vulnerable to dyspigmentation, while a thicker and more compact dermis makes facial lines less noticeable. Ethnic skin comprises a large portion of the world population. Therefore, it is important to understand the unique structural and functional differences among ethnicities to adequately treat the signs of aging.
... In addition, repair processes are less efficient. Basal glycation that occurs over a number of years contributes to aging and can lead to various pathologies by exerting deleterious effects that, while similar to those caused by diabetes, are expressed later and often to a lesser degree [130]. In contrast, it can also be hypothesized that the dietary restriction and qualitative and quantitative changes observed in the elderly diet, may limit their consumption of exogenous AGEs [131]. ...
Article
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Glycation is both a physiological and pathological process which mainly affects proteins, nucleic acids and lipids. Exogenous and endogenous glycation produces deleterious reactions that take place principally in the extracellular matrix environment or within the cell cytosol and organelles. Advanced glycation end product (AGE) formation begins by the non-enzymatic glycation of free amino groups by sugars and aldehydes which leads to a succession of rearrangements of intermediate compounds and ultimately to irreversibly bound products known as AGEs. Epigenetic factors, oxidative stress, UV and nutrition are important causes of the accumulation of chemically and structurally different AGEs with various biological reactivities. Cross-linked proteins, deriving from the glycation process, present both an altered structure and function. Nucleotides and lipids are particularly vulnerable targets which can in turn favor DNA mutation or a decrease in cell membrane integrity and associated biological pathways respectively. In mitochondria, the consequences of glycation can alter bioenergy production. Under physiological conditions, anti-glycation defenses are sufficient, with proteasomes preventing accumulation of glycated proteins, while lipid turnover clears glycated products and nucleotide excision repair removes glycated nucleotides. If this does not occur, glycation damage accumulates, and pathologies may develop. Glycation-induced biological products are known to be mainly associated with aging, neurodegenerative disorders, diabetes and its complications, atherosclerosis, renal failure, immunological changes, retinopathy, skin photoaging, osteoporosis, and progression of some tumors.
... A wrinkle is a fold, a ridge or crease in the skin, which appears as a result of the ageing processes such as glycation [7], or promoted by habitual facial expressions, skin type, photo-aging, solar UV irradiation, the effect of gravity, tobacco smoke, hormonal status, pollution, malnutrition, poor hydration and genetic factors [8,9]. ...
Article
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The study aimed to evaluate the instrumental and clinical properties of an innovative gel formulation for anti-aging treatment. This was an open, controlled study, where the eligible subjects, divided into three subgroups according to age, had to perform a single dose application of the gel on the face for a short-term evaluation and a 4-week repeated use, twice a day, for a long-term evaluation. Instrumental and clinical evaluations had to be performed mono-laterally at the level of the face (right or left side according to a predisposed randomization list) in basal conditions (T0), 20 minutes after the first dose application (T20min) and after 2 and 4 weeks of treatment (T2wks - T4wks). Thirty-three subjects completed the study showing, after only 20 minutes from the 1st product application, a clinically important and statistically significant improvement of crow’s feet, skin dullness clinical score and cutaneous microrelief clinical score (p < 0.05), after 2 weeks of treatment an improvement of skin tonicity (p < 0.05) and after 4 weeks of treatment having a significant decrease of nasolabial folds clinical score (p < 0.05). The study showed the great efficacy of an innovative anti-aging gel in reducing the skin roughness and skin dryness, improving the skin firmness and, in general, providing a global skin rejuvenation.
... AGEs are biomolecules of various nature (proteins, lipids, nucleic acids) that are abnormally covalently bound by glucose or fructose, with the final effect of inhibition of their function. The term "glycation" is used to distinguish this process from glycosilation, a physiological enzyme-mediated binding of sugars that occurs at specific sites of target molecules to enable their functions [10]. Scientific interest in AGEs has grown rapidly in the past decades: published papers went from less than 10 per year in 1991 to about one thousand per year in the last seven years (2014-2020). ...
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The surface receptor for advanced glycosylation end-products (RAGE) and its soluble (sRAGE) and endogenous secretory (EN-RAGE) forms belong to the superfamily of toll-like receptors and play important roles in inflammation and autoimmunity, directly or through binding with advanced glycosylation end-products (AGE) and advanced oxidation protein products (AOPP). We reviewed the literature on the role of RAGE in skin diseases. Research in this field is still rather limited (28 articles) but suggests the involvement of RAGE and RAGE-related pathways in chronic inflammatory diseases (lupus, psoriasis, atopic dermatitis, and lichen planus), infectious diseases (leprosy, Staphylococcus aureus-induced skin lesions), alterations of the repairing processes in diabetic skin, systemic sclerosis, and ulcers. These data prompt further research in this field, which not only will be useful to better understand the pathogenetic mechanisms of diseases, but is also likely to have intriguing clinical implications. Indeed, when their role in the complex and multifactorial inflammatory balance will be adequately defined, RAGE and related molecules could be used as markers of disease severity and/or response to treatment. Moreover, future promising therapeutic perspectives could be topical administration of some of these molecules (e.g., sRAGE) to modulate local inflammatory response and/or the development of anti-RAGE antibodies for systemic treatment.
... In fact, an unbalanced diet with the domination of refined carbohydrates has been linked to the development of obesity and obesity-associated metabolic syndrome [13][14][15], which in turn is associated with diabetes and skin diseases [16], while a balanced nutritional diet helps maintain healthy skin and ensures its normal functioning [17][18][19]. The results of several studies have demonstrated that skin aging is also associated with a higher dietary intake of carbohydrates [20][21][22]. It has been established that the primary constructional molecules of the skin, elastin and collagen, can be damaged by carbohydrates via nonenzymatic glycation, the covalent attachment of sugar to a protein, and subsequent production of AGEs [8,[23][24][25][26], and these processes are closely linked to oxidative stress [27]. ...
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Skin aging has been associated with a higher dietary intake of carbohydrates, particularly glucose and galactose. In fact, the carbohydrates are capable of damaging the skin’s vital components through nonenzymatic glycation, the covalent attachment of sugar to a protein, and subsequent production of advanced glycation end products (AGEs). This review is focused on the role of D-galactose in the development of skin aging and its relation to oxidative stress. The interest in this problem was dictated by recent findings that used in vitro and in vivo models. The review highlights the recent advances in the underlying molecular mechanisms of D-galactose-mediated cell senescence and cytotoxicity. We have also proposed the possible impact of galactosemia on skin aging and its clinical relevance. The understanding of molecular mechanisms of skin aging mediated by D-galactose can help dermatologists optimize methods for prevention and treatment of skin senescence and aging-related skin diseases.
... We showed that the cell surface RAGE contributed to HSV recognition by corneal endothelial cells and route signaling to TLR9. AGE can be formed by the collagen or elastin of the extracellular matrix in the skin of elderly individuals [24]. This can also occur in the Descemet's membrane of diseased cornea or FECD [8], and the altered extracellular matrix environment can signal back to the endothelial cells through RAGE [25]. ...
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Senescence, sterile inflammation, and infection cause dysfunction of corneal endothelial cells, leading to visual morbidity that may require corneal transplantation. With increasing age, the extracellular matrix is modified by non-enzymatic glycation forming advanced glycation end products (AGEs). The modifications are primarily sensed by the receptors for the AGEs (RAGE) and are manifested as a type I interferon response. Interestingly, in our study, human corneal endothelial cells (HCEn) cells did not respond to the typical RAGE ligands, including the AGEs, high mobility group box 1 (HMGB1), and serum amyloid-A (SAA). Instead, HCEn cells responded exclusively to the CpG DNA, which is possessed by typical corneal pathogen, herpes simplex virus-1 (HSV-1). Upon HSV-1 infection, the surface expression of RAGE was increased, and endocytosed HSV-1 was associated with RAGE and CpG DNA receptor, TLR9. RAGE DNA transfection markedly increased interferon-β secretion by CpG DNA or HSV-1 infection. HSV-1 infection-induced interferon-β secretion was abolished by TLR9 inhibition and partially by RAGE inhibition. Global transcriptional response analysis confirmed that RAGE and TLR9 were both significantly involved in type I interferon responses. We conclude that RAGE is a sensor of HSV-1 infection and provokes a type I interferon response.
... For example, hyperglycaemia accelerates glycation, a covalent bonding process that cross-links the amino acids present in the collagen and elastin that support the dermis. Cross-linked collagen fibers are incapable of repair through the usual process of remodeling, directly impacting youthful skin appearance, which relies on flexible and repairable collagen fibers (Danby, 2010). Thus chronic hyperglycaemia generated by chronic between-meal snacks could affect attractiveness because skin aging directly impacts age appearance (Nkengne et al., 2008), and age affects attractiveness (Samson et al., 2010). ...
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Since the second half of the 20th century, a massive increase in the consumption of refined carbohydrates has occurred, generating well-described detrimental health effects such as obesity, insulin resistance, type II diabetes, cardiovascular diseases and dental caries. Certain physiological mechanisms involved, particularly through chronic hyperglycaemia and hyperinsulinaemia, suggest that a non-medical trait such as facial attractiveness could also be affected. To explore this possibility, variation in facial attractiveness was evaluated relative to refined carbohydrate consumption. Attractiveness was assessed from facial pictures as judged by raters of the opposite sex. Estimates of refined carbohydrate consumption were based on the glycaemic load of three mealtimes at-higher glycaemic risk (breakfast, afternoon snack and between-meal snack). In the presence of several control variables, facial pictures of women and men with higher between-meal glycaemic loads were preferred by opposite-sex raters. Structural equation modeling suggests that this result is possibly mediated by an increase in apparent age for men and an increase in femininity for women. The different physiological ecologies of the three meals at-higher glycaemic risk are discussed as well as the interpretation of the results in terms of adaptation or maladaptation to the modern and unique dietary environment.
... This process of uncontrolled glycation also reduces the cell's ability to generate nitric oxide from L-arginine, which is required for proper cross-linking of collagen fibers, and inactivates proteins responsible for collagen and elastin repair. 22 Clinically, this results in lower skin tensile strength, as seen in the aged skin of older individuals. 24 ...
Article
BACKGROUND: Previous studies have demonstrated that a whole-food, plant-based (WFPB) diet can aid in the prevention, and in some cases reversal, of some of the leading chronic diseases in the United States. The medical literature on the relationship between diet and disease is steadily growing. Over the last decade, the possible connection between diet and many dermatological conditions has been studied, including skin aging. OBJECTIVE: As patients are increasingly seeking dietary advice from their dermatologist related to preventing and reversing the aging of skin, dermatologists need an evidence-based approach to tackle this challenging topic. This review focuses on dietary factors that contribute to telomere length, a marker for cellular aging. Although various factors contribute to accelerating telomere shortening, this review focuses on dietary factors that contribute to telomere length, specifically gerontotoxins and antioxidants. These can be measured in the blood, making them biomarkers of accelerated cellular skin aging. Included in this discussion is an evidence-based approach to increase the amount of antioxidants and decrease the amount of gerontotoxins in the diet, resulting in healthier skin. METHODS: A comprehensive MEDLINE (PubMed) literature review search was performed. Keywords used included: WFPB, telomerase, coronary artery disease, cellular aging, cigarette smoke, photoaging, telomeres, antioxidants, gerontotoxins, intrinsic cutaneous aging, extrinsic cutaneous aging, advanced glycation end products (AGEs), vitamin E, vitamin C, vitamin E, CoQ10, polyphenols, chlorophyll, zeaxanthin, polyunsaturated fatty acids, eicosapentaenoic acid, docosahexaenoic acid, alpha-linolenic acid, and monounsaturated fatty acids. Inclusion criteria included the above stated keywords and access to full text. RESULTS: A WFPB diet maximizes the antioxidant potential within our cells by providing essential vitamins, including vitamins A, C, and E. It also helps to eliminate harmful carcinogens and gerontotoxins within our bloodstream and has been shown to lengthen telomeres, which prevents cellular damage. CONCLUSION: Evidence obtained within this literature review supports a WFPB diet for preventing skin aging. .
... The increase in wrinkles in the 250 g group was notable and unexpected. Since a significant increase in total sugar intake was noted in this group after eight and sixteen weeks, this increased sugar intake may have led to glycation of collagen fibers, thereby disrupting the collagen structure [22]. The effects of whole food intake on skin health in humans is a relatively new area of research. ...
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Mangos are rich in β-carotene and other carotenoids, along with several phenolic acids that may provide oxidant defense and photoprotection to the skin. The objectives of this study are to investigate the effects of Ataulfo mango intake on the development of facial wrinkles and erythema. A randomized two-group parallel-arm study was conducted to assess 16 weeks of either 85 g or 250 g of mango intake in healthy postmenopausal women with Fitzpatrick skin type II or III. Facial photographs were captured at weeks 0, 8, and 16, and wrinkles at the lateral canthi and erythema at the cheeks were quantified. Skin carotenoid values were measured with reflection spectroscopy. Deep wrinkle severity decreased significantly in the 85 g group after 8 (p = 0.007) and 16 (p = 0.03) weeks compared to baseline measures. In contrast, those in the 250 g group showed an increase after 16 weeks in average wrinkle severity (p = 0.049), average wrinkle length (p = 0.007), fine wrinkle severity (p = 0.02), and emerging wrinkle severity (p = 0.02). Erythema in the cheeks increased with 85 g of mango intake (p = 0.04). The intake of 85 g of mangos reduced wrinkles in fair-skinned postmenopausal women, while an intake of 250 g showed the opposite effect. Further studies feeding 85 g of mangos are warranted.
Chapter
Non-enzymatic glycation of proteins occurs in intrinsic and extrinsic skin aging resulting in the formation of advanced glycation end products (AGEs). Proteins such as collagen and elastin are particularly susceptible to AGE modification. Glycated collagen is cross-linked, stiff, difficult to repair and remove from tissues. Sun exposure exacerbates glycation resulting in AGE modification of elastin which has been identified in areas of actinic elastosis. In addition, AGEs have direct effects on tissue and interact with receptors for AGEs (RAGE) increasing oxidative stress and inflammation. The use of nutritional antioxidants and cosmeceuticals that inhibit glycation will be discussed as a strategy to prevent AGE formation and ultimately skin aging.
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Nutraceuticals are defined as a food, or part of a food, that provides medical or health benefits, including the prevention and/or treatment of a disease. Specific nutraceuticals have been proven beneficial in optimising skin health and promoting healthy skin ageing. This article discusses the evidence surrounding nutrients that are essential for skin collagen synthesis and skin cell renewal. It also investigates nutrients that have been proven capable of providing anti-inflammatory and antioxidant effects in the skin, as well as protection from sun damage, and the promotion of skin hydration. In this paper, the author suggests key considerations when recommending nutraceuticals to aesthetic patients, including the importance of choosing well-researched nutrients, provided in bioavailable forms, at a dose proven to be effective. When combined with a healthy, balanced diet and the use of high-quality cosmeceuticals, nutraceuticals can help provide a global approach to optimising skin health and delaying si...
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Aging of the periorbital and midface complex is a dynamic, multifactorial, and inevitable process. This article reviews the morphologic changes that occur in the aging midface and discusses the pathogenesis of midfacial and lower eyelid aging based on its anatomic components, from the craniofacial skeleton to the skin surface. Copyright © 2015 Elsevier Inc. All rights reserved.
Book
This book describes mechanisms of skin damage generation and examines the potential impact of free radicals, reactive oxygen species (ROS) and oxidative damage on the skin aging process. It also evaluates methods to decrease skin oxidative stress, oxidative damage, and skin aging. The identification of free radical reactions as promoters of the skin aging process implies that interventions aimed at limiting or inhibiting free radical reactions should be able to reduce the rate of formation of aging-related changes with a consequent reduction of the aging rate. This book highlights how aging of the skin happens, as well as what are the causes and the best ways to prevent and treat it.
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Learn to accurately diagnose, prevent and treat all three acnes using both traditional and novel approaches to understanding the causes and selecting the most effective treatments. Acne vulgaris is an extremely common condition. It is troublesome to manage, often persisting into middle age. Exact causes are becoming clear and include several hormonal stimulants, some triggered by the Western diet, and a pathogen ignored for decades. Acnes rosacea and inversa (hidradenitis suppurativa) are discussed from entirely new viewpoints. Acne: Causes and Practical Management will provide readers at all levels with a practical, well-illustrated approach to fully understanding these disorders; a faster and more cost-effective management regimen and the rationales for their prevention. In full colour throughout and with over 200 excellent clinical images, key highlights include: Full coverage of all acne presentations - acne vulgaris, acne rosacea and acne inversa (hidradenitis suppurativa) An integrated view of the causes of the varied and overlapping acnes Preventive, novel and curative approaches to treatment Medical, surgical, and dietary components of management, fully integrated Highly practical focus on prevention, treatment and prophylaxis based on emerging pathogenetic conceps. Brought to you by one of the world's leading authorities on the subject, Acne: Causes and Practical Management will be a valuable re-education for the dermatologist and all those who treat or suffer from these three conditions.
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Background : Carotenoids play important role in delay of aging process. Orange coloured tubular calyx of flowers of Nyctanthes arbor-tristis. contains crocin, an apocarotenoid which forms a major component of stigma of saffron. Due to presence of crocin in orange coloured tubular calyx of Nyctanthes arbor-tristis, it can be used as an economical substitute to saffron for its medicinal and cosmetic utilities. Lutein from flower petals of Tagetes patula L, is another popular carotenoid which has antioxidant effect and many health benefits. The carotenoids are highly unstable when exposed to atmosphere, hence in the present study crocin and lutein rich extracts were entrapped into phytosomes to improve stability and efficacy of topical preparation. Hypothesis : Oxidative stress is considered to be a major contributor to the process of aging. Carotenoids viz, Lutein and crocin, being powerful antioxidants, can delay aging of skin through upregulating col type I gene and elastin gene. The carotenoids have very low oxidation potential, due to which they get oxidized fast and protect oxidation of other compounds which make them highly unstable. One of the ways to improve stability of these phytoconstituents, is their entrapment in phytosomes. Preparation of phytosomes will have dual advantages of improving stability as well as bioavailability of molecule. Methods : The phytosomes of Carotenoid rich extract of tubular calyx of Nyctanthes arbor-tristis L. and the petals of Tagetes patula L. (standardized for crocin and lutein content) were prepared using lipid film hydration technique and these phytosomes were then incorporated into gel base. The gel formulation was evaluated for stability as per ICH guidelines. Efficacy of formulation was evaluated by D-galactose induced aging model. Aging in skin was induced by administration of D-Galactose (100mg/kg b.w.s.c.) to albino mice for 42 days. The gel formulation was applied topically for 42 days. Then the effect of formulation on skin aging was evaluated by estimation of biochemical parameters viz. glutathione and malondialdehyde (MDA) and histopathological studies of treated skin samples. Also expression of COL type I and elastin genes was carried out from the skin samples by RT-PCR method. Results : Percent entrapment (%w/w) of crocin and lutein in phytosomes were found to be 60.20 and 50.81 respectively. Accelerated stability studies showed improvement in stability of carotenoids viz. crocin and lutein and the content of crocin and lutein in formulation was found in the range of 99.98 % w/w to 99.85%w/w at the end of three months. The formulation containing extract of Phytosomes of carotenoid rich extracts of Nyctanthes arbor-tristis L. and the petals of Tagetes patula L. exhibited potent antiaging activity through significant (p<0.05)increase in dermal and epidermal layers, and increase in GSH levels of skin as compared to the untreated group. The treatment with the gel formulation revealed upregulation of col type I and elastin genes. There was significant reduction in lipid peroxidation as revealed through reduction in MDA levels as compared to untreated group. Conclusion : Crocin and lutein have potential to prevent skin aging via upregulation of COL type I gene and elastin gene. Upregulation of genes resulted into increase in the thickness of epidermal and dermal layer along with reduction in oxidative stress in skin. Entrapment of carotenoid rich extracts of Nyctanthes arbor-tristis and Tagetes patula in Phytosomes enhanced the stability and efficacy of the formulation.
Article
Skin aging is due to extrinsic and intrinsic factors that converge, leading to macro- and microscopic alterations. Histologically, there are a loss of dermal collagen and decreased lipid production, leading to a thinning of the skin. This process is enhanced by the effect of cumulative sun exposure and oxidative damage caused by pollution, stress, and smoking. These changes manifest as wrinkles, loss of elasticity, dryness, and texture changes in mature skin. Within this reality, and the pursuit to reduce the effects of time, emerged cosmeceuticals, topical products which, in contact with skin, can cause structural and/or functional changes, not for therapy but for possible prevention and not restricted exclusively to beautification. Cosmeceuticals are still the most popular option to improve the appearance of the skin and delay aging. Although there are many examples of merely cosmetic action, manufacturers of most successful cosmeceuticals have been studying the aging process and turned this knowledge into formulations that can make a difference from a cellular point of view. In this chapter, we talk about the different classes of cosmeceuticals and how they can contribute to postmenopausal skin.
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Advanced glycation end products accumulate in the aging body and interfere with the function of many protein structures, including the skin. Diet plays an important role in skin glycation. High circulating serum glucose levels increase protein glycation, and the consumption of AGEs contributes to the total body load of these substances. Foods that are fried or have high sugar content are modern inventions. Are these foods prematurely aging the population? The answer probably is yet to come, but there are some observations that may support this contention. Notably, Asian countries where people eat a lower glycemic diet and boil and poach foods as a preferred preparation method tend to have older inhabitants. Is it possible to eat yourself young? I am not sure.
Article
The potential role of plant-based foods in the promotion of skin health is an emerging area of nutrition research. Plant-based foods are rich in bioactive compounds, including vitamin C, vitamin E, beta-carotene, polyphenols, and phenolic acids, which can contribute to oxidant defense, lower inflammation, and promote structural support of the skin. Epidemiological studies have associated higher intakes of select fruits and vegetables with positive skin health.1,2 Beneficial effects of certain fruits, vegetables, nuts, legumes, and polyphenolic-rich beverages on the skin have been reported, with each of these providing a unique phytochemical composition. While most studies use extracts, this review will focus on data from whole foods and minimally processed products. Collectively, the evidence to date suggests a promising future for plant-based dietary interventions that promote skin barrier health and function. However, additional research is required to address issues such as the optimal quality and duration of intake as well as potential mechanisms. Studies in the above areas will help formulate specific targeted dietary recommendations.
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Background: Skin reflects the general health status and is not an exception in the process of aging. Intervention studies indicate that it is possible to delay skin aging and improve skin conditions through diet-based anti-aging strategies. The purpose of the current work was to review recent existing literature regarding the role of nutrition, for and against skin aging processes. Method: This review provides updates on the effects of nutrition strategies on skin aging developed during 2008-2014. Databases such as the ISI web of science, PubMed, Scopus and Google Scholar were investigated. Result: The most important role of nutrition on skin aging is by restricting the generation or activation of reactive oxygen species (ROS) which is considered as the main cause of extrinsic skin aging. Excess sugar in daily diet accelerates aging processes through the production of advanced glycation end products that inhibit proper repair of collagen fibers. Monounsaturated and omega-3 polyunsaturated fatty acids have inverse association with severe photoaging. Antioxidants such as vitamins C, A, E, carotenoids, flavonoids and botanical antioxidants such as resveratrol, curcumin and green tea polyphenols effectively decelerate this process. Zinc, selenium and copper are coenzymes of metallothioneins and glutathione that reduce intracellular oxidative stress and result in skin protection. Conclusion: The link between nutritional issues and skin aging is an interesting but conflicting subject that requires many interventional studies. Intracellular antioxidant mechanisms are the most effective protection against skin aging.
Article
Albumin, a major plasma protein with extraordinary ligand binding properties, transports various ligands ranging from drugs, hormones, fatty acids, and toxins to different tissues and organs in the body. Albumin can undergo glycation on reacting with circulating reducing sugars, and this modification can occur even more frequently under hyperglycaemic conditions. Glycation is a non-enzymatic reaction of proteins and sugars, which gives rise to the formation of early and advanced glycation end products (AGEs). AGEs are a fundamental factor in the development and progression of severe diabetic complications such as nephropathy, neuropathy, retinopathy and cardiovascular disorders. The pathological impact of AGEs is mainly attributed to the structural modifications of proteins due to their cross-linking properties and the modification of lysine and arginine side chains. Herein, we review the structure-function effects of glycation on albumin, specifically focusing on its drug binding functions. Considering its physiological significance, there is a need to focus current research on determining the structure-function impacts of non-enzymatic glycation on serum albumin.
Chapter
Increased life spans have created a need for greater understanding of the diseases of old age including the integumentary system – the skin. The skin is the largest organ of the human body and performs multiple functions, including homeostatic regulation; prevention of percutaneous loss of fluid, electrolytes, and proteins; temperature maintenance; sensory perception; and immune surveillance. Aging involves both internal aging processes and external stressors to produce consistent changes such as thinning, drying, wrinkling, and uneven pigmentation. Understanding the fundamental physiology of changes in the epidermis, dermis, and hypodermis provides a foundation for progress in understanding the dermatological needs of those whose skin is aging. Physiological changes in aged skin include changes in biochemistry, permeability, vascularization and thermoregulation, response to irritants, immune response, repair capacity and response to injury, and neurosensory perception as well as changes at the genome level. Although aging of the skin, like other systems, is inevitable, research is beginning to define ways to both delay and minimize the troublesome effects of aging on the skin.
Chapter
Skin, known to be the largest organ, consists of epidermis and dermis. Any physiological change associated with age is ultimately reflected by a person’s skin. Two major factors responsible for premature aging are intrinsic, i.e., involvement of genes, and extrinsic that covers exposure of skin to ultraviolet (UV) radiation. UV rays induce the oxidative stress and consequently cause the loss of cellular regulation. Dietary nutriments may help the body to fight against signs of early aging as antioxidants and by regulating keratinocytes proliferation and differentiation. Main ingredients of these dietary supplements include several vitamins, minerals, phytochemicals, omega-3 fatty acids, amino acids, and probiotics. Vitamin A, C, D, and E assist in maintaining skin veracity. Zinc, copper, and selenium are the main minerals which are involved in sustenance of healthy skin. Phytochemicals consisting of flavonoids, terpenoids, and alkaloids with antibacterial, antifungal, and antioxidative property may benefit the texture and physiological parameters of skin delaying its aging. Amino acids like arginine, proline, ornithine, and glutamine alone as well as in combination support the healthy being of skin. The probiotic bacteria like Lactobacillus johnsonii and Lactobacillus plantarum commonly found in intestine aid in delaying aging by hydrating the skin as well as by showing protective effect on UV-exposed area. Though many clinical studies favor the role of dietary substances in prevention of early skin aging there is a need to cover the wider population and understand the various contributory factors.
Article
Nutraceuticals are defined as a food, or part of a food, that provides medical or health benefits, including the prevention and/or treatment of a disease. Kim Pearson covers key considerations when recommending nutraceuticals to aesthetic patients, including the importance of choosing well-researched nutrients, provided in bioavailable forms, at a dose proven to be effective
Chapter
Cosmeceuticals are considered to be all products containing biologically active substances and ingredients with beneficial effects on the skin, interfering positively on skin physiology, without therapeutic pretension, but may have preventive effects beyond beautification. Thirty-five percent of US dermatologists already include cosmeceuticals in their prescriptions, and since then cosmeceutical has represented constantly expanding group. In addition, it is certain that it is up to dermatologists to carefully evaluate each patient and the correct indication and need for the use of such substances. Although not individualized in a particular category, according to the American standards defined by the FDA, cosmeceuticals should always be evaluated to have checked their safety and efficacy profiles, since these are created with pharmacologically active substances that must respect certain pharmacokinetic principles, as they reach the deeper layers of the skin.
Article
Background: Aging is a multifactorial process and depends on both intrinsic and extrinsic factors. Procedural options for diminishing signs of intrinsic aging and cosmetic rejuvenation have expanded dramatically. However, less attention is paid to counseling patients on options for mitigating extrinsic factors related to aging. Objective: The objective of this study was to review changes that occur with intrinsic and extrinsic aging, and provide evidence-based holistic counseling recommendations that can be used synergistically with aesthetic procedures to maximize antiaging interventions. Materials and methods: A PubMed search was conducted for articles on intrinsic and extrinsic aging as it relates to skin, fat, muscle, and bone. Key clinical trials and studies on the effect of diet, hormones, exercise, sleep, stress, dental hygiene, smoking, pollution, and oxidative stress on the aging process are reviewed, and treatment recommendations are summarized based on available evidence. Results: Conventional cosmetic procedures and cosmeceuticals work together with nutritious diet, exercise, dental hygiene, hormonal balance, stress reduction, smoking and pollution avoidance, and healthy sleep patterns for a better effect on antiaging. Conclusion: A combination approach of multiple nonsurgical modalities along with healthy lifestyle recommendations to minimize intrinsic and extrinsic aging factors allows cosmetic practitioners to target multiple facets of aging concurrently and maximize the aesthetic interventions cosmetic dermatologists/practitioners provide.
Article
Campaigners have long argued that the Government should restrict the amount of sugar in food and drinks to combat the health consequences of a high sugar intake, such as diabetes and tooth decay. A tax on drinks high in sugar has recently been announced and is to be introduced in 2018. Liz Jenkinson explores why this nudge towards sugar reduction may be beneficial for people's health, including the skin
Article
The purpose of the review was to study the data of the modern literature on the effect of diet on the skin condition and the course of some dermatological diseases. Recent studies have shown a strong link between diet and a number of dermatological conditions. Food allergies and Western eating patterns can dramatically alter microbiome composition and intestinal permeability. In conditions of disturbed microbial balance and changes in the barrier function of the intestine, the penetration of immunogenic molecules into the systemic circulation, including food antigens, bacterial toxins and pathogens, which can accumulate in the skin, disrupt the epidermal barrier and contribute to chronic inflammation, increase. However, in children with atopic dermatitis, elimination diets did not show a significant advantage in reducing the severity of the disease; on the contrary, adverse events associated with malnutrition, lack of vitamins and minerals were more often recorded. Despite the fact that dietary intervention is an important aspect of the treatment and prevention of a wide range of dermatological diseases, many questions remain open today.
Chapter
Cosmeceuticals are considered to be all products containing biologically active substances and ingredients with beneficial effects on the skin, interfering positively on skin physiology, without therapeutic pretension, but may have preventive effects beyond beautification. Thirty-five percent of US dermatologists already include cosmeceuticals in their prescriptions, and since then cosmeceutical has represented constantly expanding group. In addition, it is certain that it is up to dermatologists to carefully evaluate each patient and the correct indication and need for the use of such substances. Although not individualized in a particular category, according to the American standards defined by the FDA, cosmeceuticals should always be evaluated to have checked their safety and efficacy profiles, since these are created with pharmacologically active substances that must respect certain pharmacokinetic principles, as they reach the deeper layers of the skin.
Article
Background Holistic dermatology focuses on treating the human body as a whole and implementing life-style changes to enhance the treatment and prognosis of skin disease. Understanding the interplay between modifiable life factors and patients’ dermatologic health will help physicians better inform patients on self-care methods to mitigate the burden of their skin disease(s). Objective To review the current scientific literature on the relationship between modifiable life factors and dermatological outcome of skin disorders. Methods A systematic literature search on PubMed, Cochrane, and Web of Science was conducted to identify research articles examining the relationship between dermatology and six major categories of modifiable life factors: diet, sleep, exercise, stress, alcohol, and smoking. Results A substantial amount of evidence supports the relationship between modifiable life factors and dermatologic outcomes. There were the most studies on diet, stress, alcohol, and smoking but all life factors were supported by some degree of scientific evidence. Conclusion All the modifiable life factors explored in this review play a critical role in modulating the onset and progression of skin disease. We anticipate more research studies in the future and an increasing integration of holistic dermatology into patient care.
Article
To a large extent, age-related facial skin changes, wrinkles and flabbiness, are attributed to the structural alterations in dermis, including of collagen fibers fragmentation and disorganization. There are various cosmetological correction methods that aim to activate neocollagenesis and dermal remodeling. From this perspective, intradermal injections of exogenous collagen preparations seem logical. This study aimed to investigate the efficacy and safety of Collost 7% collagen complex applied to correct the age-related facial skin changes, as well as clarify the possible mechanisms of skin rejuvenation resulting from a course of intradermal injections. 35 participants entered the study, 30 of them finished it. A set of indicators describing age-related skin changes was assessed with the help of clinical scales; the assessment revealed a pronounced improvement in the quality of the patients' skin, including smoothed relief in the area of localization of fine wrinkles. The therapy resulted in a statistically significant improvement of the skin's elasticity, which, combined with the changes discovered through US scanning (greater dermis thickness and echodensity), is an indirect indication of skin restructuring associated with accumulation of fibrous protein structures. These results allow parallels with the experimental data that shows activation of neocollagenesis in the skin of laboratory animals after a course of Collost 7% gel. The research revealed no serious adverse events. A course of collagen administered intradermally can be recommended as an aesthetic correction procedure, as well as means of prevention of atrophy that has a significant effect on skin's appearance and health status.
Article
Возрастные изменения лица в виде морщин, дряблости кожи во многом связаны со структурными изменениями дермы, в том числе с фрагментацией и дезорганизацией коллагеновых волокон. Различные методы косметологической коррекции направлены на активизацию неоколлагенеза и ремоделирование дермы. С этой точки зрения логичным видится проведение внутрикожных инъекций препаратов экзогенного коллагена. Целью исследования было изучить эффективность и безопасность применения коллагенового комплекса Коллост 7% в коррекции возрастных изменений кожи лица, а также уточнить возможные механизмы развития эффекта омоложения кожи после курса внутрикожных инъекций. В исследование были включены 34 участницы, завершили его 30 участниц. Оценка комплекса показателей возрастных изменений кожи с помощью клинических шкал продемонстрировала выраженное улучшение качества кожи и разглаживание ее рельефа, особенно в области локализации тонких морщин. После завершения курса лечения достоверно повысилась эластичность кожи лица, что вкупе с изменениями, выявленными при УЗ-сканировании (повышение толщины дермы и ее акустической плотности), косвенно свидетельствует о структурной перестройке кожи с накоплением белковых волокнистых структур. Полученные результаты позволяют проводить параллели с данными экспериментальных исследований, показывающими активизацию неоколлагенеза в коже лабораторных животных после курсового введения геля Коллост 7%. Серьезных нежелательных явлений при проведении исследования не выявлено. Курсовое внутрикожное введение коллагена можно рекомендовать как процедуру эстетической коррекции, а также в качестве профилактики развития атрофических процессов, которые существенно сказываются на внешнем виде и здоровье кожи.
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Global facial rejuvenation requires the treatment of several regions, from the forehead to the chin. One of the most common areas practitioners inject with dermal fillers is the temples, however this requires an advanced level of knowledge of both anatomy and complication management. Kev Hubbard explains the impact of ageing on the temples and outlines an evidence-based treatment protocol
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Background.ST-elevation myocardial infarction (STEMI) is associated with increased inflammation and oxidative stress, enhancing the formation of advanced glycation endproducts (AGEs). These encompass a characteristic fluorescence pattern, which can be non-invasively measured as skin autofluorescence (AF). In this study we investigate whether skin AF is elevated in STEMI, its association with inflammatory and glycaemic stress and its predictive value for future events. Methods.Skin AF was measured in 88 STEMI patients (mean age 64±13 years) within 72 hours and around six months after discharge, in 81 stable coronary artery disease (sCAD) patients (64±10 years), and in 32 healthy controls (63±11 years). The cumulative one-year incidence of all-cause mortality and hospitalisation for myocardial infarction or heart failure was documented. Results.Skin AF was significantly higher in STEMI compared with sCAD and controls, irrespective of confounders, and was associated with HbA1c and C-reactive protein. Skin AF decreased significantly in STEMI patients, when measured >200 days after discharge. In STEMI patients, skin AF above the median was predictive of future events (hazard ratio 11.6, 95% CI 1.5 to 90.8, p=0.019). Conclusion.Skin AF is elevated in STEMI, is associated with inflammation and glycaemic stress, and predicts future major adverse cardiac events. (Neth Heart J 2009;17:162–8.)
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Extracellular aging--accumulating molecular damage by glycation, oxidation, and crosslinking of long-lived extracellular proteins, mainly collagen and elastin--is a major cause of several important human aging pathologies. Crosslinking increases mechanical stiffness of blood vessels and urinary bladder. Crosslinking impairs the functioning of the kidney, heart, retina, and other tissues and organs. Glycation adducts trigger inflammatory signaling, provoking tissue damage and cancers. Crosslinking tightens up the extracellular matrix (ECM), hardening it against natural turnover processes. Known crosslink breakers (e.g., alagebrium, of the thiazolium halide family) are only partly effective because they break only a subset of AGE crosslink structures (sugar-derived alpha-diketone bridges). So far, no agent has been found that breaks the prevalent glucosepane and K2P crosslink structures. Enzymes that would be able to recognize and disassemble glycation products may be too big to migrate into the ECM and repair collagen or elastin in vivo. Two approaches to therapy development are presented here. ECM turnover enhancement would enhance natural processes to digest old ECM and replace it with new. It will be important to tune the collagen degradation to a rate slow enough to prevent dire side-effects, such as hemorrhage from leaky blood vessels as collagen molecules are removed and replaced. Glycation breaker discovery would use high-throughput screening and rational drug design to find molecules that are able to break glucosepane crosslinks and K2P crosslinks of extracellular proteins. Candidates would be further screened for selectivity and toxicity in order to avoid damage to other molecules.
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Normal human epidermal keratinocytes (NHEK) show both the Hayflick phenomenon and differentiation in vitro. The aim of this study was to induce senescence in keratinocytes using two sugars, glucose and glyoxal. Induction of senescence in early-passage NHEK was characterized by monitoring cell morphology, short-term growth characteristics, cell proliferation, and viability assay. In addition, apoptosis, senescence-associated (SA) beta-gal activity, proteasomal activity and glycation, and glycoxidation of total proteins were determined. Our results show that a 3-day treatment with 100 mM glucose or 0.1 mM glyoxal induces in early-passage NHEK various cellular and biochemical characteristics comparable to those observed in serially subcultured late passage NHEK. Furthermore, sugar-treated prematurely aged NHEK showed impaired differentiation, as measured by the quantification of involucrin. There is preliminary evidence that a preexposure of NHEK to mild heat shock (41 degrees C, 1 h, 6 h in advance) can abrogate some of the sugar-induced negative effects, which is an example of mild stress-induced hormesis. This experimental model can be useful to study the effects of potential antiaging interventions.
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Differences in skin aging features between Asians and Caucasians are commonly known, whereas little is known about such differences in various Asian populations. A survey was carried out in Tokyo, Shanghai and Bangkok to identify specific features of skin aging in each population and to evaluate whether our conventional photo scale is an appropriate tool for this type of comparative study. Eighty-seven women residing in Tokyo, 100 women residing in Shanghai, and 90 women residing in Bangkok were examined by a specialist. Facial wrinkles (forehead, glabella, upper eyelid, crow's feet, lower eyelid, cheek, nasolabial groove and mouth corner) and cheek sagging were evaluated using photo scales previously obtained from Japanese subjects. Comparisons were made according to 10-year age groups. Women in Bangkok showed the most severe level of wrinkles, followed by those in Shanghai in the three groups. Significant differences were observed between Thai and Japanese women in the intensity of wrinkles at many facial sites. Chinese women had significantly more severe wrinkles in the area around the eyes compared to Japanese women, while Thai women had significantly more severe wrinkles in the lower halves of their faces compared to Chinese women. In cheek sagging scores, significant differences were observed between Japanese and Thai women in their 30s and 50s, but not between Japanese and Chinese women or between Chinese and Thai women in all age groups. These results indicate variations in skin aging features among women from three Asian cities thereby suggesting the diversity of Asian skin. Our scaling method proved to be appropriate for facial wrinkles, but required modification to compare cheek sagging among Asian populations.
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Throughout evolution, exposure to sunlight and the photosynthesis of vitamin D(3) in the skin has been critically important for the evolution of land vertebrates. During exposure to sunlight, the solar UVB photons with energies 290-315 nm are absorbed by 7-dehydrocholesterol in the skin and converted to previtamin D(3). Previtamin D(3) undergoes a rapid transformation within the plasma membrane to vitamin D(3). Excessive exposure to sunlight will not result in vitamin D intoxication because both previtamin D(3) and vitamin D(3) are photolyzed to several noncalcemic photoproducts. During the winter at latitudes above approximately 35 degrees , there is minimal, if any, previtamin D(3) production in the skin. Altitude also has a significant effect on vitamin D(3) production. At 27 degrees N in November, very little ( approximately 0.5%) previtamin D(3) synthesis was detected in Agra (169 m) and Katmandu (1400 m). There was an approximately 2- and 4-fold increase in previtamin D(3) production at approximately 3400 m and at Everest base camp (5300 m), respectively. Increased skin pigmentation, application of a sunscreen, aging, and clothing have a dramatic effect on previtamin D(3) production in the skin. It is estimated that exposure in a bathing suit to 1 minimal erythemal dose (MED) is equivalent to ingesting between 10,000 and 25,000 IU of vitamin D(2). The importance of sunlight for providing most humans with their vitamin D requirement is well documented by the seasonal variation in circulating levels of 25-hydroxyvitamin D [25(OH)D]. Vitamin D deficiency [i.e., 25(OH)D < 20 ng/ml] is common in both children and adults worldwide. Exposure to lamps that produce UVB radiation is an excellent source for producing vitamin D(3) in the skin and is especially efficacious in patients with fat malabsorption syndromes. The major cause of vitamin D deficiency globally is an underappreciation of sunlight's role in providing humans with their vitamin D(3) requirement. Very few foods naturally contain vitamin D, and those that do have a very variable vitamin D content. Recently it was observed that wild caught salmon had between 75% and 90% more vitamin D(3) compared with farmed salmon. The associations regarding increased risk of common deadly cancers, autoimmune diseases, infectious diseases, and cardiovascular disease with living at higher latitudes and being prone to vitamin D deficiency should alert all health care professionals about the importance of vitamin D for overall health and well being.
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Glycation is the non-enzymatic reaction between reducing sugars and proteins that leads to the formation of advanced glycation end products (AGEs). In vivo skin autofluorescence (lambda(ex)/lambda(em)=370/440 nm) was used as a non-invasive clinical tool to study skin AGE accumulation in healthy panellists. Using multiple linear regression analysis, it was shown that for panellists below the age of 40, glycation associated in vivo skin fluorescence intensity increased as a function of chronological age and body mass index (BMI). Above the age of 40, the fluorescence was associated to age but not to BMI, suggesting that the effect of age became dominant over BMI. Since the accumulation of AGEs is expected to affect the biomechanical properties of the skin, in vivo skin elasticity data were gathered on a second panel. It was found that skin elasticity depended on age and BMI in a similar fashion as to what we observed for the skin fluorescence data. It is hypothesised that skin AGE accumulation contributes to the loss of skin elasticity in aged and/or overweight people.
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To investigate the effect of native, heated and glycated bovine serum albumin (BSA) on the ulcerative colitis (UC) and non-UC colonic microbiota in vitro. Continuous flow culture (CFC) models of the human colonic microbiota inoculated with faeces from UC and non-UC volunteers were maintained on BSA as growth substrate. Changes in bacterial populations and short-chain fatty acids were determined. UC and non-UC microbiota differed significantly in microbial populations, with elevated numbers of sulfate-reducing bacteria (SRB) and clostridia in the microbiota from UC patients. Compared with native BSA, glycated BSA modulated the gut microbiota of UC patients in vitro towards a more detrimental community structure with significant increases in putatively harmful bacteria (clostridia, bacteroides and SRB; P < 0.009) and decreases in dominant and putatively beneficial bacterial groups (eubacteria and bifidobacteria; P < 0.0004). The levels of beneficial short-chain fatty acids were significantly decreased by heated or glycated BSA, but were increased significantly by native BSA. The UC colonic microbiota maintained in CFC was significantly modified by glycated BSA. Results suggest that dietary glycated protein may impact upon the composition and activity of the colonic microbiota, an important environmental variable in UC.
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Aging and related diseases are accompanied by increased Oxidative Stress (OS) and accumulation of Advanced Glycation End products (AGEs). One important component of AGEs accumulation with aging appears to be the sustained exposure to dietary AGE (dAGEs), which contributes to overloading of anti-AGE receptors and depletion of anti-oxidant reserves. In this review, we present experimental animal and human data which support this postulation. Lowering the content of AGEs in the normal diet significantly prevents AGEs accumulation and the increased OS caused by aging and also extends lifespan in mice. In humans, short-term trials indicate that a Low AGEs diet reduces oxidant burden and inflammatory markers. Long-term studies are in progress and will help establish definitive causality between age-related disease states and modern dietary practices in Western societies.