Life Extension Skin Care Sale

Abstracts

Life Extension Magazine November 2011
Abstracts

Skin aging

Anti-aging properties of resveratrol: review and report of a potent new antioxidant skin care formulation.

Resveratrol, an antioxidant polyphenol from red wine, has been the subject of intense interest in recent years due to a range of unique anti-aging properties. These include cardiovascular benefits via increased nitric oxide production, down-regulation of vasoactive peptides, lowered levels of oxidized low-density lipoprotein, and cyclooxygenase inhibition; possible benefits on Alzheimer’s disease by breakdown of beta-amyloid and direct effects on neural tissues; phytohormonal actions; anticancer properties via modulation of signal transduction, which translates into anti-initiation, antipromotion, and antiprogression effects; antimicrobial effects; and sirtuin activation, which is believed to be involved in the caloric restriction-longevity effect. Here we report a resveratrol-based skin care formulation, with 17 times greater antioxidant activity than idebenone. The role of resveratrol in prevention of photoaging is reviewed and compared with other antioxidants used in skin care products.

J Cosmet Dermatol. 2008 Mar;7(1):2-7

Protective effect of resveratrol against oxidative damage of UVA irradiated HaCaT cells.

OBJECTIVE: To observe the photoprotective effect and possible mechanisms of resveratrol for ultraviolet A (UVA) irradiated HaCaT cells. METHODS: HaCaT cells under UVA irradiation with 5J/cm(2) were interfered with 0.01 mmol/L and 0.1 mmol/L resveratrol. The testing objects were divided into a control and a UVA irradiation group, and then we detected the proliferation capacity with methylthiazdyl tetrazolium (MTT) and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity, content of maleic dialdehyde (MDA) with hydroxylamine, colorimetric, thiobarbituric acid (TBA) methods. The ultrastructure was observed under electron microscope. RESULTS: Resveratrol could enhance the proliferation activity, SOD, GSH-Px activity of HaCaT cells under UVA irradiation, decrease the content of MDA in dose-dependent manner (P<0.05). The electron microscope revealed that resveratrol could relieve the injury of HaCaT cells’ ultrastructure. CONCLUSION: Resveratrol can relieve the inhibition to HaCaT cell proliferation,injury of their ultrastructure and oxidation by UVA irradiation. The protection is dose-dependent. That resveratrol raises the oxidase activity and clears the oxyradical may account for these results.

Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2006 Oct;31(5):635-9

Skin photoprotection by green tea: antioxidant and immunomodulatory effects.

Because of a characteristic aroma and health benefits, green tea is consumed worldwide as a popular beverage. The epicatechin derivatives, commonly called polyphenols, present in green tea possess antioxidant, anti-inflammatory and anti-carcinogenic properties. The major and most highly chemopreventive constituent in green tea responsible for the biochemical or pharmacological effects is (-)-epigallocatechin-3-gallate (EGCG). Epidemiological, clinical and biological studies have implicated that solar ultraviolet (UV) light is a complete carcinogen and repeated exposure can lead to the development of various skin disorders including melanoma and nonmelanoma skin cancers. We and others have shown that topical treatment or oral consumption of green tea polyphenols (GTP) inhibit chemical carcinogen- or UV radiation-induced skin carcinogenesis in different laboratory animal models. Topical treatment of GTP and EGCG or oral consumption of GTP resulted in prevention of UVB-induced inflammatory responses, immunosuppression and oxidative stress, which are the biomarkers of several skin disease states. Topical application of GTP and EGCG prior to exposure of UVB protects against UVB-induced local as well as systemic immune suppression in laboratory animals, which was associated with the inhibition of UVB-induced infiltration of inflammatory leukocytes. Prevention of UVB-induced suppression of immune responses by EGCG was also associated with the reduction in immunosuppressive cytokine interleukin (IL)-10 production at UV irradiated skin and draining lymph nodes, whereas IL-12 production was significantly enhanced in draining lymph nodes. Antioxidant and anti-inflammatory effects of green tea were also observed in human skin. Treatment of EGCG to human skin resulted in the inhibition of UVB-induced erythema, oxidative stress and infiltration of inflammatory leukocytes. We also showed that treatment of GTP to human skin prevents UVB-induced cyclobutane pyrimidine dimers formation, which are considered to be mediators of UVB-induced immune suppression and skin cancer induction. The in vitro and in vivo animal and human studies suggest that green tea polyphenols are photoprotective in nature, and can be used as pharmacological agents for the prevention of solar UVB light-induced skin disorders including photoaging, melanoma and nonmelanoma skin cancers after more clinical trials in humans.

Curr Drug Targets Immune Endocr Metabol Disord. 2003 Sep;3(3):234-42

Prevention of ultraviolet-B radiation damage by resveratrol in mouse skin is mediated via modulation in survivin.

Nonmelanoma skin cancer is the most frequently diagnosed malignancy in the United States, and multiple exposures to solar ultraviolet (UV) radiation (particularly its UV-B component, 290-320 nm), is its major cause. ‘Chemoprevention’ by naturally occurring agents is being appreciated as a newer dimension in the management of neoplasia including skin cancer. We recently demonstrated that resveratrol (trans-3, 5, 4-trihydroxystilbene), an antioxidant found in grapes, red wines and a variety of nuts and berries, imparts protection from acute UV-B-mediated cutaneous damages in SKH-1 hairless mice. Understanding the mechanism of resveratrol-mediated protection of UV responses is important. We earlier demonstrated that resveratrol imparts chemopreventive effects against multiple UV-exposure-mediated modulations in (1) cki-cyclin-cdk network, and (2) mitogen activated protein kinase (MAPK)-pathway. This study was conducted to assess the involvement of inhibitor of apoptosis protein family Survivin during resveratrol-mediated protection from multiple exposures of UV-B (180 mJ/cm(2); on alternate days; for a total of seven exposures) radiations in the SKH-1 hairless mouse skin. Our data demonstrated that topical pre-treatment of resveratrol (10 micromol in 200 microl acetone/mouse) resulted in significant inhibition of UV-B exposure-mediated increases in (1) cellular proliferations (Ki-67 immunostaining), (2) protein levels of epidermal cyclooxygenase-2 and ornithine decarboxylase, established markers of tumor promotion, (3) protein and messenger RNA levels of Survivin, and (4) phosphorylation of survivin in the skin of SKH-1 hairless mouse. Resveratrol pretreatment also resulted in (1) reversal of UV-B-mediated decrease of Smac/DIABLO, and (2) enhancement of UV-B-mediated induction of apoptosis, in mouse skin. Taken together, our study suggested that resveratrol imparts chemopreventive effects against UV-B exposure-mediated damages in SKH-1 hairless mouse skin via inhibiting Survivin and the associated events.

Photochem Photobiol. 2005 Jan-Feb;81(1):25-31

Botanical antioxidants in the prevention of photocarcinogenesis and photoaging.

Exposure of the skin to ultraviolet (UV) radiation, particularly its UV-B component (280-320 nm), from the sun results in erythema, edema, hyperplasia, hyperpigmentation, sunburn cells, immunosuppression, photoaging, and skin cancer. Amongst these various adverse effects of UV-B radiation, skin cancer and photoaging are of great concern. More recent changes in lifestyle have led to a significant increase in the amount of UV-B radiation people receive leading to a surge in the incidence of skin cancer and photoaging. As these trends are likely to continue in the foreseeable future, the adverse effect of UV-B has become a major human health concern. Therefore, development of novel strategies to reduce the occurrence of skin cancer and delay the process of photoaging are highly desirable goals. One approach to reduce their occurrence is through photochemoprevention, which we define as the use of agents capable of ameliorating the adverse effects of UV-B on the skin. Photochemoprevention via use of botanical antioxidants, present in the common diet of human have gained considerable attention as photochemopreventive agents for human use. Many such agents have also found a place in skin care products. This review will focus on the effects of selected botanical antioxidants in the prevention of photocarcinogenesis and photoaging.

Exp Dermatol. 2006 Sep;15(9):678-84

The effect of green, black and white tea on the level of alpha and gamma tocopherols in free radical-induced oxidative damage of human red blood cells.

The present study was undertaken to investigate the effect of aqueous tea extracts on lipid peroxidation and alpha and gamma tocopherols concentration in the oxidative damage of human red blood cells (RBC). RBC was taken as the model for study of the oxidative damage was induced by cumene hydroperoxide (cumOOH). The antioxidative property of leaf green tea, leaf and granulate of black tea and white tea at levels 1, 2, 4 g/150 mL of water were evaluated. The correlation was observed between reducing power of tea extract and formation of malondialdehyde--MDA (an indicator of lipid peroxidation) in oxidative damage of RBC. All tea extracts at level of 4 g/150 mL of water significantly decreased concentration of MDA. The extract of green tea in comparison to black and white tea extracts at the same levels seems to be a better protective agent against oxidative stress. The antioxidant synergism between components extracted from leaves of green tea and endogenous alpha tocopherol in the oxidative damage of red blood cells was observed. The consumption of alpha tocopherol in oxidative damage of RBC was the lowest after treatment with the highest dose of green tea extract. All tea extracts did not protect against decrease of gamma tocopherol in human erythrocytes treated with cumOOH.

Acta Pol Pharm. 2007 Mar-Apr;64(2):159-64

Green tea catechins upregulate superoxide dismutase and catalase in fruit flies.

Chinese Longjing green tea is an excellent source of polyphenol antioxidants. HPLC analysis revealed that Longjing green tea catechin extract (GTC) contained 62% epigallocatechin gallate (EGCG), 19% epigallocatechin (EGC), 9% epicatechin gallate (ECG), and 7% epicatechin (EC). Investigating the effect of GTC on the lifespan of Drosophila melanogaster, we observed that a 10 mg GTC/mL diet could prolong its 50% survival time by 36% and mean lifespan by 16%. This was consistent with 17% reduction in total body lipid hydroperoxide (LPO) level in GTC-treated flies compared to the control group. Supplementation of 10 mg GTC/mL diet increased the survival time only in wild type Oregon-R-C (OR) but not in two mutant fly lines, SOD(n108)/TM3 (gene for superoxide dismutase (SOD) was knocked out) and Cat(n1)/TM3 (gene for catalase was knocked out), when the flies were challenged with paraquat or hydrogen peroxide. Accordingly, SOD and catalase activities in OR wild type increased by 40 and 19%, respectively. RT-PCR analysis indicated that the genes for copper-zinc containing SOD (CuZnSOD), manganese containing SOD (MnSOD), and catalase were upregulated. It was concluded that prolonging lifespan by GTC in D. melanogaster was influenced, among others, by upregulation of endogenous antioxidant enzymes.

Mol Nutr Food Res. 2007 May;51(5):546-54

Antimutagenic/antioxidant activity of green tea components and related compounds.

The ability of green tea components and other antioxidant compounds to function as antimutagens/antioxidants has been well established, and their role in cancer prevention is supported by numerous epidemiological studies. We have utilized modified Ames tests, superoxide scavenging assays, and assays for protection against DNA scissions to compare and contrast the protective effects of various teas and commercial and laboratory-isolated tea components to those produced by compounds such as resveratrol, selenium, curcumin, vitamins C and E, quercetin dihydrate, sulforaphane, ellagic acid dihydrate, glutathione reduced, trolox, butylated hydroxanisole (BHA), butylated hydroxytoluene (BHT), and N-acetyl-L-cysteine (NAC). In Ames tests, employing hydrogen peroxide as a mutagen, epigallocatechin gallate (EGCG) produced the highest level of protection of all antioxidants tested. Measurement of protection against DNA scissions produced results that again showed that EGCG produced the strongest protective effects. In scavenging assays using a xanthine-xanthine oxidase (enzymatic system), epicatechin gallate (ECG) showed the highest scavenging potential. In a nonenzymatic (phenazine methosulfate-NADH) oxidizing system, EGCG once again showed the strongest effects. The implications of these and similar results are discussed in relation to cancer prevention and prevention of drug/antibiotic resistance.

J Environ Pathol Toxicol Oncol. 1999;18(3):147-58

Chelating and antiradical effect of rutin during peroxidation of lipids from microsomes and liposomes.

The antioxidative effect of rutin (vitamin P) on Fe2+-induced lipid peroxidation (LPO) in bovine heart microsomes and lecithin liposomes was studied. It was shown that the LPO-induced inhibition of microsomes and liposomes in the presence of rutin occurs via two mechanisms, i.e., association of Fe2+ ions to form an inactive complex and a direct interaction between rutin and free radicals. The contribution of these mechanisms depends on the composition of the reaction mixture. In bovine heart microsomes and liposomes, ascorbic acid has a dual activity towards LPO. At high concentrations of Fe2+ necessary for LPO induction (approximately 1 x 10(-3) M), ascorbic acid blocks LPO, whereas at low Fe2+ concentrations (less than 1 x 10(-4) M) it has a prooxidative effect. A combined use of ascorbic acid and rutin results in an additive antioxidative effect at high Fe2+ concentrations (approximately 1.10(-3) M). However, at low Fe2+ concentrations rutin acts as an antagonist of the prooxidative effect of ascorbic acid.

Biokhimiia. 1988 Oct;53(10):1660-6