Experimental Study Of MiR-181a-5p Targeting HMGB1 To Regulate The Proliferation And Apoptosis Of Acinar Cells In Acute Pancreatitis

Objective: To study the effect of miR-181a-5p targeting HMGB1 on the proliferation and apoptosis of acinar cells in acute pancreatitis(AP),and preliminarily explore its molecular mechanism.Methods:(1)The untreated AR42 J cells were used as the normal group,1x10-8 mol/L of Cerulein combined with 10 μg/ml of lipopolysaccharide(LPS)induced rat pancreatic acinar cells(AR42J)for 24 hours to establish an in vitro severe AP group.The miR-NC(empty body)and miR-181a-5p mimic were transfected into the severe AP group by lipofection method as the miR-NC control group and the miR-181a-5p overexpression group.(2)Detection of cell proliferation using CCK-8 method;TUNEL staining was used to detect apoptosis;The expression levels of miR-181a-5p,HMGB1 and Caspase-3 mRNA in AR42 J cells were detected by q RT-PCR;Western blot was used to detect the expression of HMGB1 and Caspase-3 protein.(3)The double luciferase reporter gene experiment confirmed the targeting relationship between miR-181a-5p and HMGB1.(4)Pearson correlation analysis confirmed the correlation of miR-181a-5p,HMGB1 and Caspase-3 mRNA expression.Results:(1)Compared with the normal group,the expression level of miR-181a-5p mRNA in the severe AP group was significantly decreased(P<0.01),the expression level of HMGB1 mRNA was significantly increased(P<0.01),the expression level of Caspase-3mRNA was significantly increased(P<0.05),the protein expression of HMGB1 and Caspase-3was increased(both P<0.05),the proliferative activity of cells was decreased,and the apoptosis rate was increased;Compared with the miR-NC control group,the miR-181a-5p overexpression group significantly increased the level of miR-181a-5p mRNA expression(P<0.01),significantly decreased the levels of HMGB1 and Caspase-3 mRNA expression(both P<0.01),decreased the protein expression of HMGB1 and Caspase-3(both P<0.05),increased cell proliferation activity,and decreased the rate of fine cell apoptosis.(2)The dual luciferase reporter gene showed that miR-181a-5p can inhibit the fluorescence activity of wild-type HMGB1 cells and target the regulation of HMGB1 expression.(3)Pearson correlation analysis showed that the expression level of miR-181a-5p was negatively correlated with the expression level of HMGB1(r=-0.905;P<0.01),and negatively correlated with the expression level of Caspase-3(r=-0.809;P<0.01);The expression level of HMGB1 was positively correlated with the expression level of Caspase-3(r=0.691;P<0.05).Conclusion: Low expression of miR-181a-5p in severe acute pancreatitis AR42 J inhibits cell proliferation and promotes cell apoptosis.Overexpression of miR-181a-5p can reverse this effect,and its mechanism may be related to miR-181a-5p targeting HMGB1 and inhibiting the expression of Caspase-3.