Role of Resveratrol in Regulating Cutaneous Functions

Resveratrol-coated chitosan mats promote angiogenesis for enhanced wound healing in animal model

BACKGROUND

Growing incidences of chronic wounds recommend the development of optimal therapeutic wound dressings. Electrospun nanofibers have been considered to show potential wound healing properties when accompanied by other wound dressing materials. This study aimed to explore the potential role of Chitosan (CS) nanofibrous mats coated with resveratrol (RS) as an antioxidant and pro-angiogenic agent in rat models of skin wound healing.

METHODS

Electrospun chitosan/polyethylene oxide (PEO) nanofibers were prepared using electrospinning technology and coated by 0.05 and 0.1 mg.ml resveratrol named as (CS/RS 0.05) and (CS/RS 0.1), respectively. The scaffolds were characterized physiochemically such as in vitro release study, TGA, FTIR spectroscopy analysis, biodegradability, and human dermal fibroblast seeding assay. The scaffold was subsequently used in vivo as a skin substitute on a rat skin wound model.

RESULTS

In vitro tests revealed that all scaffolds promoted cell adhesion and proliferation. However, more cell viability was observed in CS/RS 0.1 scaffold. The biocompatibility of the scaffolds was validated by MTT assay, and the results did not show any toxic effects on human dermal fibroblasts. It was observed that RS-coated scaffolds had the ability to release RS in a controlled manner. In in vivo tests CS/RS 0.1 scaffold had the greatest impact on the healing process by improving the neodermis formation and modulated inflammation in wound granulation tissue. Histological analysis revealed enhanced vascular endothelial growth factor expression, epithelialization and increased depth of wound granulation tissue.

CONCLUSIONS

The RS-coated CS/PEO nanofibrous scaffold accelerates wound healing and may be useful as a dressing for cell transfer and clinical skin regeneration.

The Promising Role of Polyphenols in Skin Disorders

The biochemical characteristics of polyphenols contribute to their numerous advantageous impacts on human health. The existing research suggests that plant phenolics, whether consumed orally or applied directly to the skin, can be beneficial in alleviating symptoms and avoiding the development of many skin disorders. Phenolic compounds, which are both harmless and naturally present, exhibit significant potential in terms of counteracting the effects of skin damage, aging, diseases, wounds, and burns. Moreover, polyphenols play a preventive role and possess the ability to delay the progression of several skin disorders, ranging from small and discomforting to severe and potentially life-threatening ones. This article provides a concise overview of recent research on the potential therapeutic application of polyphenols for skin conditions. It specifically highlights studies that have investigated clinical trials and the use of polyphenol-based nanoformulations for the treatment of different skin ailments.

Polyphenols from Mediterranean Plants: Biological Activities for Skin Photoprotection in Atopic Dermatitis, Psoriasis, and Chronic Urticaria

Polyphenols are a diverse class of natural compounds that are widely distributed in various fruits, vegetables, and herbs. They possess antioxidant and anti-inflammatory properties and bring benefits in the prevention and treatment of various diseases. Studies suggested that polyphenols may improve cardiovascular health and may have neuroprotective effects. The Mediterranean region is a vast area. Although the territory encompasses a wide variety of cultures and dietary patterns, there are some commonalities in terms of the plant-based foods and their polyphenol content. Such polyphenols have been studied for their potential photoprotective effects on the skin. We focused on nutraceutical effects of Mediterranean plants in skin photoprotection in atopic dermatitis, psoriasis, and chronic urticaria. Results highlight the importance of exploring natural compounds for therapeutic purposes. The wide variety of polyphenols found in different foods and plants allows for a diverse range of pharmacological effects. The Mediterranean diet, rich in polyphenol-containing foods, is associated with a lower incidence of various chronic diseases, including dermatological conditions. While more research is needed to fully understand the mechanisms of action and optimal dosing of polyphenols, there is initial evidence to support their potential use as adjunctive therapy for atopic dermatitis, psoriasis, and chronic urticaria.

The PI3K-Akt-mTOR and Associated Signaling Pathways as Molecular Drivers of Immune-Mediated Inflammatory Skin Diseases: Update on Therapeutic Strategy Using Natural and Synthetic Compounds

The dysregulated phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway has been implicated in various immune-mediated inflammatory and hyperproliferative dermatoses such as acne, atopic dermatitis, alopecia, psoriasis, wounds, and vitiligo, and is associated with poor treatment outcomes. Improved comprehension of the consequences of the dysregulated PI3K/Akt/mTOR pathway in patients with inflammatory dermatoses has resulted in the development of novel therapeutic approaches. Nonetheless, more studies are necessary to validate the regulatory role of this pathway and to create more effective preventive and treatment methods for a wide range of inflammatory skin diseases. Several studies have revealed that certain natural products and synthetic compounds can obstruct the expression/activity of PI3K/Akt/mTOR, underscoring their potential in managing common and persistent skin inflammatory disorders. This review summarizes recent advances in understanding the role of the activated PI3K/Akt/mTOR pathway and associated components in immune-mediated inflammatory dermatoses and discusses the potential of bioactive natural products, synthetic scaffolds, and biologic agents in their prevention and treatment. However, further research is necessary to validate the regulatory role of this pathway and develop more effective therapies for inflammatory skin disorders.

Nanotechnology-Based Topical Delivery of Natural Products for the Management of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic eczematous inflammatory disease that may arise from environmental, genetic, and immunological factors. Despite the efficacy of current treatment options such as corticosteroids, such approaches are mainly focused on symptom relief and may present certain undesirable side effects. In recent years, isolated natural compounds, oils, mixtures, and/or extracts have gained scientific attention because of their high efficiency and moderate to low toxicity. Despite their promising therapeutic effects, the applicability of such natural healthcare solutions is somewhat limited by their instability, poor solubility, and low bioavailability. Therefore, novel nanoformulation-based systems have been designed to overcome these limitations, thus enhancing the therapeutic potential, by promoting the capacity of these natural drugs to properly exert their action in AD-like skin lesions. To the best of our knowledge, this is the first literature review that has focused on summarizing recent nanoformulation-based solutions loaded with natural ingredients, specifically for the management of AD. We suggest that future studies should focus on robust clinical trials that may confirm the safety and effectiveness of such natural-based nanosystems, thus paving the way for more reliable AD treatments.

Effects of Natural Polyphenols on Skin and Hair Health: A Review

The skin is the largest organ of the body and plays multiple essential roles, ranging from regulating temperature, preventing infections, to ultimately affecting human health. A hair follicle is a complex cutaneous appendage. Skin diseases and hair loss have a significant effect on the quality of life and psychosocial adjustment of individuals. However, the available traditional drugs for treating skin and hair diseases may have some insufficiencies; therefore, a growing number of researchers are interested in natural materials that could achieve satisfactory results and minimize adverse effects. Natural polyphenols, named for the multiple phenolic hydroxyl groups in their structures, are promising candidates and continue to be of scientific interest due to their multifunctional biological properties and safety. Polyphenols have a wide range of pharmacological effects. In addition to the most common effect, antioxidation, polyphenols have anti-inflammatory, bacteriostatic, antitumor, and other biological effects associated with reduced risk of a number of chronic diseases. Various polyphenols have also shown efficacy against different types of skin and hair diseases, both in vitro and in vivo, via different mechanisms. Thus, this paper reviews the research progress in natural polyphenols for the protection of skin and hair health, especially focusing on their potential therapeutic mechanisms against skin and hair disorders. A deep understanding of natural polyphenols provides a new perspective for the safe treatment of skin diseases and hair loss.

Enhanced Anti-Skin-Aging Activity of Yeast Extract-Treated Resveratrol Rice DJ526

Resveratrol is a powerful antioxidant that defends against oxidative stress in cells but is not found in large quantities in plants. Resveratrol-enriched rice DJ526, which was developed as a functional crop, shows a diverse range of biological activities. Resveratrol production is measured as total resveratrol and its glycoside, piceid, which is mainly found in plant-derived resveratrol. In the present study, elicitation using yeast extract (YE), methyl jasmonate, and jasmonic acid increased resveratrol production in DJ526 rice seeds. DJ526 seeds elicited using 1 g/L (YE1) and 5 g/L yeast extract (YE5) showed enhanced resveratrol production and antioxidant activity. YE5-treated DJ526 seeds showed decreased melanin content by 46.1% and 37.0% compared with the negative control and DJ526 (non-elicitation), respectively. Both YE1 and YE5 efficiently improved the wound-healing activity by reducing the wound gap faster than in untreated cells, with a maximum rate of 60.2% at 24 h and complete closure at 48 h. YE1 and YE5 significantly decreased the levels of proinflammatory cytokine, TNF-α, and enhanced collagen synthesis in inflammatory cells. These findings indicate that YE-treated resveratrol rice DJ526 may improve resveratrol production and could be an active antiaging ingredient for cosmetic and skin therapy applications.

Antioxidant Activity of Resveratrol Diastereomeric Forms Assayed in Fluorescent-Engineered Human Keratinocytes

Resveratrol is a powerful antioxidant molecule. In the human diet, its most important source is in Vitis vinifera grape peel and leaves. Resveratrol exists in two isoforms, cis- and trans. The diastereomeric forms of many drugs have been reported as affecting their activity. The aim of this study was to set up a cellular model to investigate how far resveratrol could counteract cytotoxicity in an oxidant agent. For this purpose, a keratinocyte cell line, which was genetically engineered with jelly fish green fluorescent protein, was treated with the free radical promoter Cumene hydroperoxide. The antioxidant activity of the trans-resveratrol and its diastereomeric mixture was evaluated indirectly in these treated fluorescent-engineered keratinocytes by analyzing the cell number and cell proliferation index. Our results demonstrate that cells, which were pre-incubated with resveratrol, reverted the oxidative damage progression induced by this free radical agent. In conclusion, fluorescent-engineered human keratinocytes represent a rapid and low-cost cellular model to determine cell numbers by studying emitted fluorescence. Comparative studies carried out with fluorescent keratinocytes indicate that trans-resveratrol is more efficient than diastereomeric mixtures in protecting cells from the oxidative stress.

Promising Natural Products in New Drug Design, Development, and Therapy for Skin Disorders: An Overview of Scientific Evidence and Understanding Their Mechanism of Action

The skin is the largest organ in the human body, composed of the epidermis and the dermis. It provides protection and acts as a barrier against external menaces like allergens, chemicals, systemic toxicity, and infectious organisms. Skin disorders like cancer, dermatitis, psoriasis, wounds, skin aging, acne, and skin infection occur frequently and can impact human life. According to a growing body of evidence, several studies have reported that natural products have the potential for treating skin disorders. Building on this information, this review provides brief information about the action of the most important in vitro and in vivo research on the use of ten selected natural products in inflammatory, neoplastic, and infectious skin disorders and their mechanisms that have been reported to date. The related studies and articles were searched from several databases, including PubMed, Google, Google Scholar, and ScienceDirect. Ten natural products that have been reported widely on skin disorders were reviewed in this study, with most showing anti-inflammatory, antioxidant, anti-microbial, and anti-cancer effects as the main therapeutic actions. Overall, most of the natural products reported in this review can reduce and suppress inflammatory markers, like tumor necrosis factor-alpha (TNF-α), scavenge reactive oxygen species (ROS), induce cancer cell death through apoptosis, and prevent bacteria, fungal, and virus infections indicating their potentials. This review also highlighted the challenges and opportunities of natural products in transdermal/topical delivery systems and their safety considerations for skin disorders. Our findings indicated that natural products might be a low-cost, well-tolerated, and safe treatment for skin diseases. However, a larger number of clinical trials are required to validate these findings. Natural products in combination with modern drugs, as well as the development of novel delivery mechanisms, represent a very promising area for future drug discovery of these natural leads against skin disorders.

Preventative effects of antioxidants on changes in sebocytes, outer root sheath cells, and Cutibacterium acnes-pretreated mice by particulate matter: No significant difference among antioxidants

OBJECTIVES

Particulate matter (PM) is an air pollutant that can damage human skin; antioxidants have shown some efficacy in alleviating PM-induced skin inflammation. We investigated the antioxidant effects of punicalagin, epigallocatechin-3-gallate (EGCG), and resveratrol on PM-induced changes in cultured human sebocytes, outer root sheath (ORS) cells, and Cutibacterium acnes-pretreated mice.

METHODS

Sebocytes and ORS cells were cultured with 100 μg/mL PM10 and 5 μM punicalagin, 1 μM EGCG, or 1 μM resveratrol for 24 h. In C. acnes-pretreated mice, inflammatory nodules were treated with 100 μg/mL PM10 and 5 μM punicalagin, 1 μM EGCG, or 1 μM resveratrol. Cell viability was measured using an MTT assay. Antioxidant effects were analyzed according to RNA expression, using real-time PCR, as well as reactive oxygen species (ROS) and sebum measurements.

RESULTS

Antioxidants inhibited the upregulation of inflammatory cytokines, matrix metalloproteinase, aryl hydrocarbon receptor, and NF-kB as well as the production of ROS induced by PM10 in cultured sebocytes and ORS cells. The preventative effects of punicalagin and EGCG on biomarker expression in cultured sebocytes and ORS cells were slightly greater than those of resveratrol, though the difference was not significant. In C. acnes-pretreated mice, the antioxidants inhibited inflammatory cytokine and matrix metalloproteinase expression as well as sebum production.

CONCLUSIONS

Antioxidants effectively reduced the expression of inflammatory biomarkers and sebum production in cultured sebocytes, ORS cells, and C. acnes-pretreated mice.

Compatibility of Different Formulations in Pentravan® and Pentravan® Plus for Transdermal Drug Delivery

The potential therapeutic benefit of transdermal delivery systems for some active pharmaceutical ingredients (APIs) has been well-established for decades within the scientific community. However, together with the clinical efficacy, there is the need for an evaluation of the stability of such APIs in bases with known transdermal capabilities, which is necessary to provide the compounding pharmacist with confidence when providing transdermal products. In this study, the stability of danazol, metformin HCl, and resveratrol as individual ingredients, as well as metformin HCl, resveratrol, and Vitamin D3 in combinations at bracketed high and low concentrations, were evaluated over a period of 6 months, using a ready-to-use transdermal vehicle for compounding pharmacies (Pentravan® or Pentravan® Plus). The five formulations tested (F1: Danazol 50 mg/g + MiodesinTM 85 mg/g in Pentravan®, F2: Metformin HCl 200 mg/g in Pentravan®, F3: Resveratrol 200 mg/g in Pentravan®, F4: Metformin HCl 100 mg/g + Resveratrol 100 mg/g + Vitamin D3 5000 IU in Pentravan®, and F5: Metformin HCl 200 mg/g + Resveratrol 200 mg/g + Vitamin D3 5000 IU in Pentravan® Plus) presented a beyond-use date of at least 6 months, presenting high convenience for the compounding pharmacies.

Topical Cyperus rotundus essential oil for treatment of axillary hyperpigmentation: a randomized, double-blind, active- and placebo-controlled study

BACKGROUND

The oil of the grass Cyperus rotundus (purple nutsedge) is an effective and safe treatment option for a variety of conditions. It has anti-inflammatory and antipigmenting properties. There have been no clinical trials comparing topical C. rotundus oil with skin-lightening treatments for axillary hyperpigmentation.

AIM

To assess the efficacy of C. rotundus essential oil (CREO) in treating axillary hyperpigmentation, and compare with another active treatment hydroquinone (HQ) and a placebo (cold cream) in this study.

METHODS

The study included 153 participants, who were assigned to one of three study groups: CREO, HQ group or placebo group. A tri-stimulus colorimeter was used to assess pigmentation and erythema. Two independent experts completed the Physician Global Assessment, and the patients completed a self-assessment questionnaire.

RESULTS

CREO had significantly (P < 0.001) better depigmenting effects than HQ. CREO and HQ did not differ significantly in terms of depigmentation effects (P > 0.05); however, there were statistically significant differences in anti-inflammatory effects and decrease in hair growth (P < 0.05) in favour of CREO.

CONCLUSIONS

CREO is a cost-effective and safe treatment for axillary hyperpigmentation.

Dermal Drug Delivery of Phytochemicals with Phenolic Structure via Lipid-Based Nanotechnologies

Phenolic compounds are a large, heterogeneous group of secondary metabolites found in various plants and herbal substances. From the perspective of dermatology, the most important benefits for human health are their pharmacological effects on oxidation processes, inflammation, vascular pathology, immune response, precancerous and oncological lesions or formations, and microbial growth. Because the nature of phenolic compounds is designed to fit the phytochemical needs of plants and not the biopharmaceutical requirements for a specific route of delivery (dermal or other), their utilization in cutaneous formulations sets challenges to drug development. These are encountered often due to insufficient water solubility, high molecular weight and low permeation and/or high reactivity (inherent for the set of representatives) and subsequent chemical/photochemical instability and ionizability. The inclusion of phenolic phytochemicals in lipid-based nanocarriers (such as nanoemulsions, liposomes and solid lipid nanoparticles) is so far recognized as a strategic physico-chemical approach to improve their in situ stability and introduction to the skin barriers, with a view to enhance bioavailability and therapeutic potency. This current review is focused on recent advances and achievements in this area.

Omega-3- and Resveratrol-Loaded Lipid Nanosystems for Potential Use as Topical Formulations in Autoimmune, Inflammatory, and Cancerous Skin Diseases

Resveratrol (RSV) and omega 3 (ω₃), because of their biological favorable properties, have become subjects of interest for researchers in dermocosmetic and pharmaceutical industries; however, these bioactives present technological limitations that hinder their effective delivery to the target skin layer. To overcome the stability and skin permeation limitations of free bioactives, this work proposes a combined strategy involving two different lipid nanosystems (liposomes and lipid nanoparticles) that include ω₃ in their lipid matrix. Additionaly, RSV is only encapsulated in liposomes that provid an adequate amphiphilic environment. Each formulation is thoroughly characterized regarding their physical–chemical properties. Subsequently, the therapeutic performance of the lipid nanosystems is evaluated based on their protective roles against lipid peroxidation, as well as inhibition of cicloxygenase (COX) and nitric oxid (NO) production in the RWA264.7 cell line. Finally, the lipid nanosystems are incorporated in hydrogel to allow their topical administration, then rheology, occlusion, and RSV release–diffusion assays are performed. Lipid nanoparticles provide occlusive effects at the skin surface. Liposomes provide sustained RSV release and their flexibility conferred by edge activator components enhances RSV diffusion, which is required to reach NO production cells and COX cell membrane enzymes. Overall, the inclusion of both lipid nanosystems in the same semisolid base constitutes a promising strategy for autoimmune, inflammatory, and cancerous skin diseases.

Resveratrol and endoplasmic reticulum stress: A review of the potential protective mechanisms of the polyphenol

The endoplasmic reticulum (ER) is an organelle that performs a set of essential functions in cellular biology. These include synthesis of lipids, homeostasis of calcium, and controlling the folding of proteins. Inflammation and oxidative stress are two important reasons behind the accumulation of misfolded or unfolded proteins in the ER. In such circumstances, a series of measures are undertaken in the cell which are collectively called unfolded protein response (UPR). The aim of UPR is to reduce the burden of protein aggregates and promote survival. However, extended and unrestricted ER stress (ERS) can induce further inflammation and apoptosis. ERS and the UPR are involved in different diseases such as neurodegenerative and cardiovascular diseases. Resveratrol (RSV), a natural polyphenol, has well-documented evidence supporting its numerous biological properties including antioxidant, antiinflammatory, antiobesity, antidiabetic, and antiischemic activities. The compound is also known for its potential beneficial effects on cognitive function and liver, kidney, and lung health. In this review, the role of ERS in several pathological conditions and the potential protective effects of RSV are discussed. However, the scarcity of clinical data means that more research needs to be conducted to gain a lucid understanding of RSV's effects on endoplasmic reticulum stress (ERS) in humans.

Sirtuin 1 and Skin: Implications in Intrinsic and Extrinsic Aging-A Systematic Review

Skin, as the outermost organ of the body, is constantly exposed to both intrinsic and extrinsic causative factors of aging. Intrinsic aging is related to compromised cellular proliferative capacity, and may be accelerated by harmful environmental influences with the greatest significance of ultraviolet radiation exposure, contributing not only to premature aging, but also to skin carcinogenesis. The overall skin cancer burden and steadily increasing global antiaging market provide an incentive for searching novel targets to improve skin resistance against external injury. Sirtuin 1, initially linked to extension of yeast and rodent lifespan, plays a key role in epigenetic modification of proteins, histones, and chromatin by which regulates the expression of genes implicated in the oxidative stress response and apoptosis. The spectrum of cellular pathways regulated by sirtuin 1 suggests its beneficial impact on skin aging. However, the data on its role in carcinogenesis remains controversial. The aim of this review was to discuss the relevance of sirtuin 1 in skin aging, in the context of intrinsic factors, related to genetic premature aging syndromes, as well as extrinsic modifiable ones, with the assessment of its future application. PubMed were searched from inception to 4 January 2021 for relevant papers with further search carried out on ClinicalTrials.gov. The systematic review included 46 eligible original articles. The evidence from numerous studies proves sirtuin 1 significance in both chronological and premature aging as well as its dual role in cancer development. Several botanical compounds hold the potential to improve skin aging symptoms.

Study of Resveratrol's Interaction with Planar Lipid Models: Insights into Its Location in Lipid Bilayers

Resveratrol, a polyphenolic molecule found in edible fruits and vegetables, shows a wide range of beneficial effects on human health, including anti-microbial, anti-inflammatory, anti-cancer, and anti-aging properties. Due to its poor water solubility and high liposome-water partition coefficient, the biomembrane seems to be the main target of resveratrol, although the mode of interaction with membrane lipids and its location within the cell membrane are still unclear. In this study, using electrophysiological measurements, we study the interaction of resveratrol with planar lipid membranes (PLMs) of different composition. We found that resveratrol incorporates into palmitoyl-oleoyl-phosphatidylcholine (POPC) and POPC:Ch PLMs and forms conductive units unlike those found in dioleoyl-phosphatidylserine (DOPS):dioleoyl-phosphatidylethanolamine (DOPE) PLMs. The variation of the biophysical parameters of PLMs in the presence of resveratrol provides information on its location within a lipid double layer, thus contributing to an understanding of its mechanism of action.

Identifying a Role of Red and White Wine Extracts in Counteracting Skin Aging: Effects of Antioxidants on Fibroblast Behavior

Dermal fibroblasts are the main actor in many proteins' secretion, including collagen, preserving skin function. Free radicals are involved in skin aging and damages involving different cellular components. The imbalance between reactive oxygen species (ROS) amount and natural antioxidant enzymes negatively affects skin homeostasis. Natural compounds have recently emerged as a potential anti-aging tool in tissue regeneration. In the present paper we evaluated the antioxidant activity of white and red wines, considering their probable use, as raw materials, for the formulation of cosmetic products with anti-aging properties. We studied a method that would allow the removal of the alcoholic fraction of wines and determined their composition by LC-MS analysis. We then tested the possible cytotoxic effects of red and white wines on fibroblasts by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay, and their antioxidant activity by the catalase activity test in stressing conditions. Finally, we evaluated their anti-aging potential through the β-galactosidase colorimetric assay. Our results showed that wine extracts exhibit a remarkable antioxidant and anti-aging activity, especially on cells exposed to a marked stressful event. These properties could suggest their possible application as cosmetical products for skin regeneration.

Menopause and the Skin: Old Favorites and New Innovations in Cosmeceuticals for Estrogen-Deficient Skin

Estrogen is a pivotal signaling molecule; its production is regulated by the expression of the aromatase (CYP19A1) gene from ovarian and peripheral tissue sites, and it is transmitted via estrogen receptors to influence many important biological functions. However, the narrative for this overview focuses on the decline of 17β-estradiol levels from ovarian sites after menopause. This estrogen-deficient condition is associated with a dramatic reduction in skin health and wellness by negatively impacting dermal cellular and homeostatic mechanisms, as well as other important biological functions. The changes include loss of collagen, elastin, fibroblast function, vascularity, and increased matrix metalloproteinase(s) enzymatic activities, resulting in cellular and extracellular degradation that leads to dryness, wrinkles, atrophy, impaired wound healing/barrier function, decreased antioxidant capacity [i.e., defense against reactive oxygen species (ROS) and oxidative stress], decreased attractiveness and psychological health, and increased perception of aging. While topical estrogen may reverse these changes, the effects of today's low-dose systemic hormone treatments are not well established, raising the need for more concentrated local administration of hormones or newer cosmeceutical agents such as selective estrogen receptor modulators (SERMs), including phytoestrogens that have become major active ingredients for skin care products, especially when addressing estrogen-deficient skin. Two example compounds are presented, an analog of resveratrol (i.e., 4'-acetoxy resveratrol) and the isoflavonoid equol, both of which are involved in a variety of biochemical/molecular actions and mechanisms, as demonstrated via in vitro and clinical studies that enhance human dermal health, especially in estrogen-deficient skin.

4′,7-Isoflavandiol (Equol) Enhances Human Dermal Fibroblast Renewal and Has Effects Similar to 17β-Estradiol in Stimulating Collagen and Elastin Expression. Cell Cycle and RT-PCR Analysis without Phenol Red

Polyphenols have general health benefits including anti-photoaging influences to counter the negative effects of ultra-violet (UV) rays from solar light (via the generation of reactive oxygen species (ROS) and oxidative stress (OS)), which leads to the stimulation of matrix metalloproteinases (MMPs) that break down collagen and elastin. The changes in elastin and collagen represent major factors in dermal aging along with a decrease in skin fibroblast number and function. The purpose of this study was to determine the influence of a polyphenolic molecule, 4′,7-Isoflavandiol (Equol) at 10 nM on: (1) fibroblast number and function via cell cycle testing (including apoptosis) and collagen protein expression (types I and III) using long-term (eight-week) 3D human fibroblast cultures by intracellular fluorescent-activated cell sorting (FACS) analysis, and (2) quantifying elastin gene expression levels in short-term (four day) cultures using human monolayer fibroblasts by RT-PCR. In both in vitro testing methods, the presence of phenol red (tissue culture indicator) interfered with the parameter results. Therefore, all experiments were performed without phenol red. Using FACS analysis in the long-term 3D cultures exposure to 10 nM of equol for four days significantly increased the percentage of cycling fibroblasts (rejuvenation) above vehicle control (dimethyl sulfoxide (DMSO)) or 17β-estradiol levels, while apoptosis was not altered by any treatment. In addition, in the long-term cultures, collagen levels were significantly increased in the equol and 17β-estradiol treatments above vehicle control values. In short-term cultures, 10 nM of equol or 17β-estradiol significantly increased elastin gene expression levels above vehicle control values. In summary: (a) phenol red may interfere with tissue culture parameter results and (b) the polyphenolic equol compound, derived from plants, may provide protection against photoaging in cosmetic formulations by stimulating collagen, elastin, and enhancing fibroblast renewal.