Effect of glycine on COX-2 expression in the rat nonalcoholic fatty liver

Objective To explore the effect of glycine on COX-2 expression in liver tissue of rats with non-alcoholic fatty liver di-sease(NALFD).Methods Fifty-four rats were randomly divided into 3 groups:control group,model group(high fat-fed)and treatment group(high fat-fed+glycine).These rats were sacrificed at the end of weeks 8,12,16.The blood of abdominal aorta was obtained,and the levels of serum ET and MDA in liver were measured.Histopathology of liver tissue was analyzed by light microscope,and COX-2 expression in liver tissue was detected by immunohistochemistry.Results The serum MDA of the liver tissue increase significantly at week 12 in model group(P0.05).Compared with control group and treatment group,serum endotoxin significantly increased at week 16(P0.05),while it increased at the end of weeks 8,12,but there was no significant difference.COX-2 expression was negative in 3 groups at the end of weeks 8 and 12 by immunohistochemistry.But COX-2 expression was positive in model group and treatment group at the end of week 16,and there was significant difference among 3 groups(P0.05).Conclusion Non-alcoholic fatty liver disease accompanies intestinal endotoxemia,and glycine could attenuate the levels of endotoxemia,MDA,and the expression of COX-2,which could prevent NALFD.