Panax vietnamensis protects mice against carbon tetrachloride-induced hepatotoxicity without any modification of CYP2E1 gene expression.

In order to explore the effect of Panax vietnamensis on carbon tetrachloride-induced hepatotoxicity, mice were pretreated for 7 days with either crude extract or total saponins. Crude extract and total saponins dramatically decreased carbon tetrachloride-induced increase of serum GST alpha level (-50.0%, -49.5% respectively). Serum AST level was significantly decreased only with total saponins (-52.2%) and ALT level was slightly modified. In vitro experiments shown that both preparations at high concentrations (> 2000 micrograms/ml) are able to inhibit CYP2E1 enzymatic activity in mouse and human microsomes. However, we did not observe any modification of Cyp2e1 gene expression (enzymatic activity, protein and mRNA levels) in mice treated with either crude extract or total saponins. Taken together, these data demonstrated that Panax vietnamensis could be used as an hepatoprotectant. However, the mechanism of action is not associated with CYP2E1 expression, as previously suggested in vitro in rat for total saponins from Panax ginseng.