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 tetrachlorid e-induced hepatotoxicity, mice were pretreated for 7 days with either crude extract or total saponins. Crude extract and total saponins dramatically d ecreased carbon tetrachloride-induced increase of serum GST alpha level (- 50.0%, -49.5% respectively). Serum AST level was significantly decreased on ly with total saponins (-52.2%) and ALT level was slightly modified. In vit ro experiments shown that both preparations at high concentrations (> 2000 mug/ml) are able to inhibit CYP2E1 enzymatic activity in mouse and human mi crosomes. However, we did not observe any modification of Cyp2e1 gene expre ssion (enzymatic activity, protein and mRNA levels) in mice treated with ei ther crude extract or total saponins. Taken together, these data demonstrat ed that Panax vietnamensis could be used as an hepatoprotectant. However, t he mechanism of action is not associated with CYP2E1 expression, as previou sly suggested in vitro in rat for total saponins from Panax ginseng.