Expression and significance of autophagy-related genes in acute pancreatitis / 中华胰腺病杂志

ABSTRACT

Objective To examine the expression and analyze the significance of autophagy-related gene microtubule-associated protein 1 light chain 3 (MAP1-LC3,LC3),p62 and lysosorne-associated membrane protein 2 (LAMP-2) in pancreatic tissues of mice with acute pancreatitis (AP).Methods Twenty mice were randomized into AP group and control group,and the number of mice was equal between two groups.AP group was intra-peritoneally injected by 20％ L-arginine solution (two injections of 4 g/kg body weight,every 1 h) in the dosage of 4 g/l kg twice every 1 hour to establish AP model,while control group was administered with equal volume of normal saline by intra-peritoneal injection.All the mice were euthanized at 24 hour after the last injection.Pancreatic histopathological changes were measured.In addition,the protein expressions of LC3,p62 and LAMP-2 were detected by Western blot.Results No obvious pathological changes were observed in control group.Pancreatic acinar edema,structure destruction,missing,the obvious widening of interlobular septum,small interlobular septum and acinar septum,and the necrosis of acinar cells at different degrees were observed in AP group.The pathological score for tissue edema,hemorrhage,necrosis and inflammation in AP group was 3.13 ± 0.50,2.83 ± 0.32,3.25 ± 0.46 and 3.16 ± 0.47,respectively,which was all 0 in control group.The differences were statistically significant between AP group and control group (P ＜ 0.01).In AP group,the ratio of LC3-Ⅱ/LC3-Ⅰ,p62 and LAMP-2 protein in pancreatic tissue were 1.16 ± 0.08,0.94 ± 0.04 and 0.35 ± 0.04,respectively,which were 0.24 ± 0.02,0.34 ± 0.03 and 0.95 ± 0.03 in control group.The ratio of LC3-Ⅱ/LC3-Ⅰ and p62 protein in pancreatic tissue in AP group were much higher than those in control group,while LAMP-2 in AP group was lower than that in control group,and there was statistically significant difference between two groups (all P ＜0.01).Conclusions Intraperitoneal injection of L-arginine could induce acute pancreatitis,and autophagy is impaired,which was associated with decreased LAMP-2 protein expression.