Psidium guajava Leaf Extracts and Their Quercetin Protect HepG2 Cell Lines Against CCL4 Induced Cytotoxicity.

The present study was carried out to evaluate the in vitro cytoprotective effects of Psidium guajava and their isolated quercetin fraction to reduce the CCl₄ (carbon tetrachloride) induced toxicity in HepG2 cell lines (Hepatocellular carcinoma G2). Silymarin was used as a standard drug to compare the protective effects of plant extracts in infected cell lines. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay, cell viability assay, leakage parameters [Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and Lactate dehydrogenase (LDH)], lipid peroxidation and reduced glutathione (GSH) levels were used to find out the protection of human derived HepG2 cells against CCl₄-induced damage. The levels of cytotoxicity, viability and GSH were reduced. While the activities of AST, ALT, LDH and lipid peroxidation was increased in CCl₄-treated groups. The treatment of P. guajava and their isolated quercetin fractions (100, 200, 300 µg/mL) decreased the elevated levels of all these parameters. The results of the present study suggest that the ethanolic extract of P. guajava leaf and their isolated quercetin fractions can able to reduce the CCl₄-induced cytotoxicity in HepG2 cell lines.