MiR-145 inhibited lipopolysaccharide-induced apoptosis of gastric mucosal via up-regulating JNK-mediated cytoprotective autophagy

Abstract

It has been reported that specific microRNA could inhibit apoptosis of gastric mucosa. Our study was designed to investigate the effect and mechanisms of miR-145 in gastric mucosa. Gastric mucosal cells (GES-1) were treated with null-vector or miR-145 over expression plasmid. Cell viability was determined by CCK-8 assay and detection of apoptosis by flow cytometry. Autophagic and apoptosis protein expression and c-Jun NH2-terminal kinase (JNK) phosphorylation were determined by Western blotting. Autophagy response and JNK activities were inhibited by specific inhibitor, 3MA or SP600125, respectively. LDH release assay was used to detect cytotoxicity. We confirmed that miR-145 triggered an autophagic response in GES-1 cells and depended on JNK activation. Blocking autophagy or JNK activation with specific inhibitor, 3MA or SP600125, potentiated cell death and caspase-3 activation. Furthermore, we confirmed that miR-145 enhanced the viability of GES-1 cells, phosphorylation of JNK and inhibited apoptosis of gastric mucosal miR-145 inhibited apoptosis of gastric mucosal via up-regulating JNK-mediated cytoprotective autophag.