The protective effects of selenium-enriched probiotics on carbon tetrachloride-induced liver fibrosis in rats Short title:Effects of selenium-enriched probiotics on rat liver fibrosis

This study aimed to investigate the effects of Se-enriched probiotics（SP） on the liver fibrosis induced by CCI4 in rats.The results showed that SP significantly decreased serum alanine aminotransferase（87.0±1.96） U/L,aspartate aminotransferase（101 ±3.13） U/L,hepatic hydroxyproline（898 ±72.5） μg/g and malondialdehyde（2.39±0.34） nmol/mg levels,but increased glutathione peroxidase（37.2 ± 3.19） U/mg,superoxide dismutase（201± 19.2） U/mg and glutathione levels（3.32±0.25） mg/g（P<0.05） in rats treated by CCl4.SP suppressed hepatic inflammation and necrosis induced by CCl4.Moreover,SP significantly reduced the expression of a-smooth muscle actin,collagen,TGF-β1,TIMP-1 and inflammation-related gene and induced apoptosis of activated hepatic stellate cells（P<0.05） in rats treated by CCl4.Our results suggest that SP could protect the liver fibrosis by attenuating hepatic oxidative stress,suppressing hepatic inflammation and inducing apoptosis of hepatic stellate cells.