Using natural dietary sources of antioxidants to protect against ultraviolet and visible radiation-induced DNA damage: an investigation of human green tea ingestion. [2010.11.03]
Oral ingestion of green tea is a potent dietary source of antioxidant polyphenols... Further investigation should consider whether this dietary-induced protection could be extended to cells of the skin.
Anti-angiogenic effects of epigallocatechin-3-gallate in human skin. [2010.08.05]
Epigallocatechin-3-gallate (EGCG) is the main polyphenol component of green tea...
The Promise of Natural Products for Blocking Early Events in Skin Carcinogenesis. [2010.01.26]
This perspective on Stratton et al.
Protective effects of green tea extracts on photoaging and photommunosuppression. [2009.08]
OBJECTIVES: This study aimed to investigate whether the sunscreen-containing 2-5% green tea extracts (GTEs) protect ultraviolet irradiation (UVR)-induced photoaging and photoimmunosuppression... CONCLUSIONS: GTEs-containing sunscreens have potential photoprotective effects on UVR-induced photoaging and photoimmunosuppression.
Topical application of green and white tea extracts provides protection from solar-simulated ultraviolet light in human skin. [2009.06]
BACKGROUND: Tea polyphenols have been found to exert beneficial effects on the skin via their antioxidant properties. AIMS: We sought to determine whether topical application of green tea or white tea extracts would prevent simulated solar radiation-induced oxidative damages to DNA and Langerhans cells that may lead to immune suppression and carcinogenesis...
Inhibition of UVB-induced skin tumor development by drinking green tea polyphenols is mediated through DNA repair and subsequent inhibition of inflammation. [2009.05]
Consumption of green tea polyphenols (GTPs) in drinking water prevents photocarcinogenesis in mice; however, the molecular mechanisms underlying this effect have not been fully elucidated. Using IL-12p40 knockout (KO) mice and their wild-type counterparts and an established photocarcinogenesis protocol, we found that although administration of GTPs (0.2%, w/v) in drinking water significantly reduced UVB-induced tumor development in wild-type mice, this treatment had a nonsignificant effect in IL-12-KO mice...
Green tea and skin cancer: photoimmunology, angiogenesis and DNA repair. [2007.05]
Human skin is constantly exposed to numerous noxious physical, chemical and environmental agents.New mechanistic information strongly supports and explains the chemopreventive activity of GTPs against photocarcinogenesis.
Effects of polyphenols on skin damage due to ultraviolet A rays: an experimental study on rats. [2007.05]
CONCLUSION: These results show a protective effect of EGCG when applied topically before UVA exposure. No benefit was detected when EGCG was applied after UV exposure.
Photoprotective effects of green tea polyphenols. [2007.02]
Non-melanoma skin cancer is the most common malignancy in humans and is equivalent to the incidence of malignancies in all other organs combined in the United States. Current methods of prevention depend on sunscreens in humans, efficacy of which is largely undetermined for non-melanoma skin cancers.
Safety studies on epigallocatechin gallate (EGCG) preparations. Part 2: dermal, acute and short-term toxicity studies. [2006.05]
Green tea extract and its principal active ingredient, epigallocatechin gallate (EGCG), are gaining attention and increased usage due to their healthful properties. Despite the increasing demand for these products, few studies have examined their safety... From these studies a no-observed adverse effect level of 500 mg EGCG preparation/kg/day was established.
Green tea polyphenol epigallocatechin-3-gallate inhibits the expression of nitric oxide synthase and generation of nitric oxide induced by ultraviolet B in HaCaT cells. [2006.02.20]
BACKGROUND: Nitic oxide (NO) has been implicated in the pathogenesis of various inflammatory diseases, including sunburn and pigmentation induced by ultraviolet irradiation. Epigallocatechin-3-gallate (EGCG) is the major effective component in green tea and can protect skin from ultraviolet-induced damage. The purpose of this study was to investigate the protective mechanisms of EGCG on inducible nitric oxide synthase (iNOS) expression and NO generation by ultraviolet B (UVB) irradiation in HaCaT cells... CONCLUSIONS: Green tea derived-EGCG can inhibit and down regulate the UVB-induced activation and translocation of NF-kappaB, expression of iNOS mRNA and generation of NO respectively, indicating EGCG may play a protective role from UVB-induced skin damage.
Chemoprevention of photocarcinogenesis by selected dietary botanicals. [2006.02]
Epidemiological, clinical and laboratory studies have implicated solar ultraviolet (UV) radiation as a tumor initiator, tumor promoter and complete carcinogen, and their excessive exposure can lead to the development of various skin disorders including melanoma and nonmelanoma skin cancers...
Double-blinded, placebo-controlled trial of green tea extracts in the clinical and histologic appearance of photoaging skin. [2005.07]
BACKGROUND: Green tea extracts have gained popularity as ingredients in topical skin care preparations to treat aging skin. Green tea polyphenolic compounds have significant antioxidant and anti-inflammatory activities, and studies suggest that these extracts help mediate ultraviolet radiation damage. OBJECTIVE: To evaluate the effects of a combination regimen of topical and oral green tea supplementation on the clinical and histologic characteristics of photoaging... CONCLUSION: Participants treated with a combination regimen of topical and oral green tea showed histologic improvement in elastic tissue content. Green tea polyphenols have been postulated to protect human skin from the cutaneous signs of photoaging, but clinically significant changes could not be detected. Longer supplementation may be required for clinically observable improvements.
Green tea polyphenols prevent ultraviolet light-induced oxidative damage and matrix metalloproteinases expression in mouse skin. [2004.06]
Chronic exposure of solar ultraviolet (UV) light to human skin results in photoaging...
Green tea extract suppresses the age-related increase in collagen crosslinking and fluorescent products in C57BL/6 mice. [2003.11]
Collagen crosslinking during aging in part results from Maillard reaction endproducts of glucose and oxoaldehydes. Because of the tight link between oxidative and carbonyl stress, we hypothesized that natural antioxidants and "nutriceuticals" could block collagen aging in C57BL/6 mice...
Skin photoprotection by green tea: antioxidant and immunomodulatory effects. [2003.09]
Because of a characteristic aroma and health benefits, green tea is consumed worldwide as a popular beverage.
Cutaneous photoprotection from ultraviolet injury by green tea polyphenols. [2001.03]
BACKGROUND: In animal models, extracts from green tea have been shown to be remarkably effective at reducing the severity of adverse human health effects of overexposure to ultraviolet (UV) radiation. Although sunscreens and other photoprotective measures have traditionally been used for this purpose, there is a need for additional measures and natural products are increasingly being explored for that purpose. OBJECTIVE: Our purpose was to evaluate the effect of polyphenols from green tea on parameters associated with acute UV injury... CONCLUSION: Polyphenolic extracts of green tea are effective chemopreventive agents for many of the adverse effects of sunlight on human health and may thus serve as natural alternatives for photoprotection.
Green tea and skin. [2000.08]
CONCLUSIONS: The outcome of the several experimental studies suggests that green tea possess anti-inflammatory and anticarcinogenic potential, which can be exploited against a variety of skin disorders. Although more clinical studies are needed, supplementation of skin care products with green tea may have a profound impact on various skin disorders in the years to come. Arch Dermatol. 2000;136:989-994
Green tea protects against psoralen plus ultraviolet A-induced photochemical damage to skin. [1999.12]
The use of psoralens combined with exposure to ultraviolet A radiation is a major form of treatment for psoriasis and a number of other common skin diseases. Although psoralen plus ultraviolet A treatment is highly effective, careful follow-up cohort studies have shown that it greatly increases risk for the development of cutaneous squamous cell carcinoma and melanoma...
Photoprotective effect of black tea extracts against UVB-induced phototoxicity in skin. [1999.10]
In previous studies, we showed that green tea and black tea extracts and their major polyphenolic constituents protect against UVB light-induced carcinogenesis in murine skin...
