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Review Article
Photoprotective Effect of Tea and its Extracts
against Ultraviolet Radiation-Induced Skin Disorders
Na-Na Li1, Li Deng1,
Li-Ping Xiang2 and Yue-Rong Liang1*
1Zhejiang University
Tea Research Institute, Hangzhou, 310058,
2Guizhou Tea and Tea
Products Quality Supervision and Inspection Center,
Zunyi 563100, China
*For
correspondence: Email:
yrliang@zju.edu.cn; Tel: +86 571 88982704;
Fax: +86 571 88982704
Received: 28 December 2013
Revised accepted: 18
February 2014
Tropical Journal of
Pharmaceutical Research, March 2014;
13(3):
475-483
http://dx.doi.org/10.4314/tjpr.v13i3.24
Abstract
Ultraviolet (UV) exposure
induces photodamage of skin. It is a matter of concern
that the level of UV radiation reaching the earth
surface is increasing as a result of depletion of the
stratospheric ozone, and climate change. It is urgently
necessary to develop strategies to protect the skin from
UV-induced injuries. Tea extracts are gaining increasing
attention as a supplement in skin care products.
However, the factors contributing to the photoprotective
effects of tea extracts have not been systematically
defined and conflicting results about the effect of tea
extracts on photodamage have been reported. In this
paper, the literature dealing with the use of tea and
its extracts for the prevention of photodamage to the
skin as well as the photoprotective effects of tea and
its extracts have been highlighted. The potential
chemopreventive agents in tea include catechins,
caffeine, polysaccharides, apigenin and luteolin which
inhibit, reverse or retard the process of the skin
photodamage via their sunscreen and antioxidant
properties, regulation of signal transduction pathway
and gene expression, alleviation of DNA damage, and
modulation immunological function are also presented.
Existing gaps in this research field include incomplete
clarity of photochemopreventive mechanism of tea, the
adverse or side effects of tea extracts owing to
residues or impurity and the instability of the
functional components of tea during storage.
Keywords: Camellia sinensis;
Photoageing, Antioxidant, Tea extracts, Sunburn, DNA
damage; Immunological modulation; Gene expression. |