The cytoprotective effect of pure phenolic compounds on HepG2 cell lines against tert-butylhydroperoxide­ induced oxidative stress / Nurul Hidayah Adnan

Reactive oxygen species (ROS) such as tert-butylhydroperoxide (t-BOOH) is a product of normal cellular metabolism and are recognized to be harmful or beneficial to living systems. Antioxidants such as superoxide dismutase (SOD) and catalase efficiently remove ROS surplus to maintain the normal cell homeostasis. When the exposure to oxidative stress becomes extended, antioxidant enzymes naturally occurring in the cells might not be able to protect the cells anymore. There are many studies regarding phenolic compounds nowadays. This is may be due to low cost in discovery and developing stage or to find an alternative to agents used in medication therapy yet producing many side effects. Cytoprotective effects of three different phenolic compounds which are resveratrol, catechin and quercetin had been studied and the outcome obtained showed that each of them affected catalase activities in the cells. HepG2 cell I ines were plated and treated by different concentrations (I, I 0, I 00 and 1000 µM) of pure phenolic compounds to provide the protection before the cells were exposed to 200 µM of t-BOOH. This study showed that I 000 µM of resveratrol, catechin and quercetin significantly increased catalase activities as compared to treat with 200 µM t-BOOH, without phenolic compounds treatment. Resveratrol, catechin and quercetin at different concentration ( 1-1000 µM) showed some tendency to increase SOD activity but the differences as compared to O µM was not significant. In conclusion, resveratrol, catechin and quercetin showed protection against t-BOOH (200 µM) in HepG2 cell lines.