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Photoprotective effects of green tea polyphenols

Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Photodermatology Photoimmunology and Photomedicine (Impact Factor: 1.3). 03/2007; 23(1):48-56. DOI: 10.1111/j.1600-0781.2007.00262.x
Source: PubMed

ABSTRACT 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. Green tea polyphenols have the greatest effect with respect to chemoprevention and have been found to be most potent at suppressing the carcinogenic activity of UV radiation. They protect against many of the other damaging effects of UV radiation such as UV-induced sunburn response, UV-induced immunosuppression and photoaging of the skin. They exert their photoprotective effects by various cellular, molecular and biochemical mechanisms in in vitro and in vivo systems. Green tea polyphenols thus have the potential, when used in conjunction with traditional sunscreens, to further protect the skin against the adverse effects of ultraviolet radiation.

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    • "The leaves of this plant are immersed in boiling water a process that, for the most part, prevents oxidation and polymerization of the plant's polyphenols. It is these compounds that are thought to be the major chemopreventive mediators (Yusuf et al., 2007). Another tea presenting antioxidant properties and protection against DNA oxidation is mate tea or yerba mate (Ilex paraguariensis). "
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    ABSTRACT: We evaluated the effects green and mate teas on oxidative and DNA damages in rats exposed to ultraviolet radiation. Were utilized 70 adult male Wistar rats that received daily oral or topic green or mate tea treatment during exposed to radiation by seven days. After, animals were killed by decapitation. Thiobarbituric acid-reactive species levels, protein oxidative damage were evaluated in skin and DNA damage in blood. Our results show that the rats exposed to ultraviolet radiation presented DNA damage in blood and increased protein carbonylation and lipid peroxidation in skin. Oral and topic treatment with green tea and mate tea prevented lipid peroxidation, both treatments with mate tea also prevented DNA damage. However, only topic treatment with green tea and mate tea prevented increases in protein carbonylation. Our findings contribute to elucidate the beneficial effects of green tea and mate tea, here in demonstrated by the antioxidant and antigenotoxic properties presented by these teas.
    12/2013; 37(1):195-201. DOI:10.1016/j.etap.2013.11.028
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    • "UVB is associated with an important part of skin damage, being considered a major risk factor for the development of acute inflammation , photoaging and non-melanoma skin cancer [2]. Although there are many successful treatment methods for these conditions, an increasing interest emerges for effective prevention [3]. The most specific effect of the exposure of human skin to UVB radiation is represented by DNA damage as a consequence of the direct action of UVB on the DNA molecule with the formation of cyclobutane-pyrimidine dimers (CPD), pyrimidine (6-4) pyrimidone photodimers (6-4PP), 8-hydroxy-2 0 -deoxyguanosine (8-OHdG) [4], which, if remain unrepaired can initiate photocarcinogenesis . "
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    ABSTRACT: BACKGROUND: In the recent years, the use of natural antioxidants as photochemoprotective agents against skin damages produced by ultraviolet radiation gained considerable attention. Our goal was to show that the hydroethanolic extract obtained from red grape seeds, Burgund Mare (BM) variety could have a protective effect on keratinocytes exposed to UVB radiation. MATERIALS AND METHODS: HaCaT keratinocytes were treated with BM extract 30min. before UVB exposure. The effect was evaluated by assessing cell viability with MTT; the generation of lipid peroxides with malondialdehide (MDA) assay; DNA damage using comet assay; the quantification of DNA photolesions by ELISA and apoptosis by immunocytochemistry with AnnexinV. RESULTS: After irradiation with UVB, HaCaT cells pretreated with BM showed: increased cell viability compared to those exposed to UVB only; significantly lower lipid peroxides level; the lesion scores and DNA photolesions were significantly lower and a significant reduction of the cells undergoing apoptosis. CONCLUSIONS: These results recommend the use of the BM extract as photochemoprotective agent as such or in combination with sunscreens and/or other natural products with similar or complementary properties.
    Journal of photochemistry and photobiology. B, Biology 11/2012; 118. DOI:10.1016/j.jphotobiol.2012.10.008 · 2.80 Impact Factor
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    • "Although the exact cause of RPE cell degeneration is not clear, it was postulated that the sensitivity of RPE cells to UV light could be an important factor (Noell et al., 1966; Young, 1988; Szaflik et al., 2009; Xu et al., 2010). GTP is a kind of natural antioxidant extracted from green tea which could attenuate cell damage against UV irradiation (Yusuf et al., 2007; Wu et al., 2009; Katiyar et al., 2010; Xu et al., 2010). It was also proved that GTP could protect against damage induced by UV irradiation in vivo (Kelly et al., 2001; Lu, 2002; Jane et al., 2003; Vayalil et al., 2004). "
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    ABSTRACT: Green tea polyphenol (GTP) is water-soluble medical additives which possess particular significance as free radical scavengers or antioxidants in biological systems. The present study investigated the protective effect of green tea polyphenols against ultraviolet B (UVB)–induced damage to human retinal pigment epithelial (RPE) cells. Microstructure of RPE cells was examined by transmission electron microscopy and the expression of c-fos was examined in messenger ribonucleic acid (mRNA) as well as protein level by using real-time polymerase chain reaction (PCR) and western blot assay. The results indicated that UVB irradiation-induced injuries in RPE cells were markedly suppressed by GTP. The mechanism of GTP protected RPE cells from UVB damage might be related to signal pathway regulation and DNA restoration, suggesting GTP as a potential candidate for further development and aslo a chemoprotective material for prevention of UVB exposure induced eye diseases.
    Journal of medicinal plant research 03/2012; 6(9). DOI:10.5897/JMPR11.1546 · 0.88 Impact Factor
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