Effects of schisandrin B pretreatment on tumor necrosis factor-alpha induced apoptosis and Hsp70 expression in mouse liver

Tumor necrosis factor-alpha (TNF alpha) could cause apoptosis in hepatic tissue of D-galactosamine sensitized mice, as evidenced by the increase in the extent of DNA fragmentation. The hepatic apoptosis induced by TNFa was associated with hepatocellular damage as assessed by plasma alanine aminotransferase activity. Schidandrin B (Sch B) pretreatment at daily doses ranging from 0.5 to 2 mmol/kg for 3 days caused a dose-dependent protection against TNF alpha -induced apoptosis in mice. The hepatoprotection was accompanied by a parallel reduction in the extent of hepatocellular damage. The same Sch B pretreatment regimens increased hepatic Hsp70 level in a dose-dependent manner. The relevance of Sch B-induced increase in Hsp70 expression to the prevention of TNF alpha -triggered hepatic apoptosis remains to be elucidated.