Forskning

August 1, 2011

Complimentary antioxidant function of caffeine and green tea polyphenols on normal human skin fibroblast

J Jagdeo & N Brody, Complimentary antioxidant function of caffeine and green tea polyphenols on normal human skin fibroblast, Journal of Drugs in Dermatology,2011, Volume 10, Issue 7.

The study of free radicals is particularly relevant in the context of human skin carcinogenesis and photoaging because of these oxidants ability to induce DNA mutations and produce lipid peroxidation by products, including 4-hydroxy-2-nonenal (HNE). Therefore it is important to identify and evaluate agents with the ability to modulate intracellular free radicals and HNE. The purpose of this study was to investigate the ability of antioxidants green tea polyphenols and caffeine, alone and in combination, to modulate the hydrogen peroxide induced upregulation of reactive oxygen species free radicals and HNE in normal human skin fibroblasts WS-1 cells in vitro. Green tea polyphenols and caffeine were selected for evaluation because these compounds have demonstrated antioxidative properties in various skin models. Furthermore, green tea polyphenols and caffeine share a close natural botanical association as caffeine is present in green tea as well. Hydrogen peroxide is a well-known generator of free radicals that is produced during endogenous and UV-induced oxidation processes in human skin and was used to upregulate reactive oxygen species and HNE in normal human fibroblast WS-1 cells. Using a flow cytometry-based assay, the results demonstrate that at 0.001% concentration, green tea polyphenols alone, and in combination with 0.1 mM caffeine, inhibited the upregulation of hydrogen peroxide generated free radicals and HNE in human skin fibroblasts in vitro. Caffeine alone demonstrated limited antioxidant properties.