Photoprotective effects of green tea polyphenols

Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Photodermatology Photoimmunology and Photomedicine (Impact Factor: 1.26). 03/2007; 23(1):48-56. DOI: 10.1111/j.1600-0781.2007.00262.x
Source: PubMed


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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    • "Non-melanoma skin cancer has the highest incidence rate among all cancers [1]. In the US alone, more than 1 million cases are diagnosed every year, which is equivalent to the incidence of malignancies in all other organs combined [2]. The phosphoinositide 3-kinase (PI3K) pathway is frequently targeted in the germ line for somatic mutations in many human cancers. "
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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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