The protective effects of epigallocatechin gallate on lipopolysa ccharide-induced hepatotoxicity: an in vitro study on Hep3B cells

OBJECTIVES In the present study, our aim was to investigate the possible protective effects of epigallocatechin gallate (EGCG) on lipopolysaccharide (LPS)-induced hepatotoxicity by using Hep3B human hepatoma cells. Specifically, the study examines the role of some proinflammatory markers and oxidative damage as possible mechanisms of LPS-associated cytotoxicity. Consequently, the hepatocellular carcinoma cell line Hep3B was chosen as a model for investigation of LPS toxicity and the effect of EGCG on LPS-exposed cells. MATERIALS AND METHODS The Hep3B human hepatoma cells were used for this study. The cytotoxic effects of chemicals (EGCG and LPS), AST and ALT levels, SOD and CAT activities, GSH-Px level and TNF-alpha and IL-6 levels were detected by using different biochemical and molecular methods. LPS and EGCG were applied to cells at various times and doses. RESULTS The highest treatment dose of EGCG (400 µM) led to a dramatic decrease in SOD level and increase in CAT and GSH levels. Additionally, the highest dose of EGCG also led to a dramatic increase in TNF-alpha and IL-6 levels. On the other hand, effective doses of EGCG (200 and 100 µM) normalized all related parameters levels. CONCLUSION LPS caused hepatotoxicity, but interestingly, a high dose of EGCG was found to be a cytotoxic agent in this study. However, other two doses of EGCG led to a decrease in both inflammatory cytokine levels and antioxidant enzyme levels. Further studies should examine the effect of EGCG on secondary cellular signaling pathways.