Abstract

Orthosiphon aristatus Blume, a member of the Lamiaceac family, is a medicinal herb known useful as a diuretic agent, used popularly in Vietnam and the nations in the world. In our previous research, it is found that O. aristatus had strong antioxidant in both methods of the ferric reducing/antioxidant power assay and the 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging assay. The purpose of the present study was to examine the methanolic extract of O. aristatus with strong antioxidative activity against carbon tetrachloride (CCl4) induced cytotoxicity in isolated mouse hepatocytes using a modified procedure of Kiso. Suspension of isolated mouse hepatocytes incubated in E’MEM medium under a gas 95% O2 and 5% CO2, 37oC in 2h before the addition of 1.5% CCl4 and incubated in 45’. CCl4 administration significantly increased serum alanine aminotransferase (ALT) activity, a biochemical marker of hepatocyte injury in medium. Pretreatment with different concentration of methanolic extract of O. aristatus reduced ALT level. Methanolic extract with concentration of 0.1 và 0.25 mg/ml, were decreased ALT activity 60% compared to toxic group, remaining of the serum ALT was 104% compared to control group. The results of the present study showed that strong antioxidative activity of methanolic extract plays a crucial role in providing protection against such hepatocyte damage, and also supported the traditional believes on hepatoprotective effect of O. aristatus extract.