Protective effect of Misgurnus anguillicaudatus polysaccharide on immunological liver injury in mice

The modulation influence of Misgurnus anguillicaudatus polysaccharide on the expression of nitric oxide synthase (NOS), B cell lymphoma/leukemia-2 (Bcl-2, hepatocyte apoptosis inhibitor) and Bcl-2 associated X protein (Bax, hepatocyte apoptosis promoter) in mice's liver with immunological hepatic injury was studied. Immunological hepatic injury was induced by lipopolysaccharide (LPS ip, 0.2 mg kg− 1) in bacillus calmette-guerin (BCG ip, 0.15 g kg− 1, once, before 7 days) primed mice. The mice were treated with M. anguillicaudatus polysaccharides (MAP) at doses of 30 mg kg− 1, 60 mg kg− 1, respectively, ig, once a day, and sacrificed on the 8th day after ip LPS for 4 h. In comparison to the normal mice, the nitric oxide production, serum alanine aminotransferase (sALT) and serum glutathione s-transferase (sGST) levels were increased significantly, iNOS and Bax expression were up-regulated by 16.5 times (P < 0.001 vs. normal animal group) and 0.43 times (P < 0.05, vs. normal animal group) respectively, cNOS expression was not apparently changed, and no Bcl-2 expression was found in immunological hepatic injury mice. The M. anguillicaudatus polysaccharide (30 mg kg− 1) could reduce sALT, sGST and nitric oxide production levels (vs. BCG-LPS model control group) by 25.1%, 42.6% and 17.8% respectively, and the expression of iNOS and Bax was decreased (vs. BCG-LPS model control group) by 80.3% and 38.4%, while the expression of cNOS and Bcl-2 increased (vs. BCG-LPS model control group) by 58.7% and 352%, respectively.