Regulatory role of microRNA-1187 in caspase-8 mediated hepatocyte apoptosis / 中华传染病杂志

ABSTRACT

Objective To observe the regulatory role of microRNA-1187(miR-1187)in hepatocyte apoptosis through miR-1187 targeting regulation of caspase-8 mRNA expression.Methods The acute liver failure model was established by injection of D-galactosamine plus lipopolysaccharides(LPS)in BALB/c mice.The liver tissues were collected for LNA-miRNA array analysis and functional analysis of genes targeted by miRNA.Embryonic murine hepatocyte cell line 2(BNL-CL2)was cultivated in vitro and treated with tumor necrosis factor(TNF)-α and D-galactosamine to induce the transfection of miR-1187 in transfected group or untransfected group.The expressions of miR-1187 and caspase-8 mRNA were detected by real-time polymeramse chain reaction(PCR)and caspase-8 protein was determined by Western blot.The apoptosis rate was detected by flow cytometry.The comparison of means between groups was done by t test.Results The miR-1187 signal was deceased with the development of acute liver failure.The 3'UTR of caspase-8 mRNA had direct binding sites with miR1187.In BNL-CL2 cell experiments,miR-1187 was down-regulated in untransfected group and decreased more slowly in transfected group(t=6.371,P<0.01).The expression of caspase-8 mRNA was up-regulated in untransfected group and increased less in transfected group(t=4.539,P<0.01).The apoptosis rate in transfected group was significantly lower than untransfected group(t=3.365,P<0.05).Conclusios miR-1187 is one of inhibitors of hepatocyte apoptosis.High expression of miR-1187 could regulate the expression of caspase-8 mRNA,thus inhibit the apoptosis of hepatocytes.