| Abstract: | AIM: To explore the role and potential mechanism of miR-30 b regulation of autophagy in hepatic ischemiareperfusion injury(IRI).METHODS: An animal model of hepatic IRI was generated in C57BL/6 mice. For in vitro studies, AML12 cells were immersed in mineral oil for 1 h and then cultured in complete Dulbecco's Modified Eagle's Medium(DMEM)/F12 to simulate IRI. Mice and cells were transfected with miR-30 b agomir/mimics or antagomir/inhibitor to examine the effect of miR-30 b on autophagy to promote hepatic IRI. The expression of miR-30 b was measured by real-time polymerase chain reaction. Apoptotic cells were detected by terminal uridine nickend labeling(TUNEL) staining, and cell viability was detected by methylthiazole tetrazolium assay. The expression of light chain 3, autophagy-related gene(Atg)12, Atg5, P62, and caspase-3 were detected by western blotting analysis.RESULTS: miR-30 b levels were significantly downregulated after hepatic IRI, and the numbers of autophagosomes were increased in response to IRI both in vivo and in vitro. These findings demonstrate that low levels of miR-30 b could promote hepatic IRI. Furthermore, we found that miR-30 b interacted with Atg12-Atg5 conjugate by binding to Atg12. Overexpression of miR-30 b diminished Atg12 and Atg12-Atg5 conjugate levels, which promoted autophagy in response to IR. In contrast, downregulation of miR-30 b was associated with increased Atg12-Atg5 conjugate levels and increased autophagy.CONCLUSION: miR-30 b inhibited autophagy to alleviate hepatic ischemia-reperfusion injury via decreasing the Atg12-Atg5 conjugate. |
