The Relationship Between MiR-27a Expression And PPAR? Regulation In Rat Ischemic Injury Model Of Cortical Neurons

Object: To investigate the role of miR-27 a and PPAR? in the pathogenesis of ischemic cerebrovascular disease and to provide experimental evidence from miRNA level.Methods: This study established the model of cerebral ischemia and hypoxia in rat cortical neurons,using LDH and MTT to test the injury and viability of neuronal cell.The expression of miR-27 a PPAR?,NF-kB p65,Caspas3-cleaved and Bcl-2 in neurons were detected by real-time quantitative PCR and Western blot at different time point after ischemia and hypoxia.Real-time quantitative PCR and Western blot were used to detected the expression of miR-27 a and PPAR? in neurons after overexpression of miR-27 a and silencing of PPAR?.Finally,the relationship between miR-27 a and PPAR? was verified by double luciferase assay.Results: Compared with control group,the expression of miR-27 a was increased and the expression of PPAR? was decreased at the different time points after ischemia and hypoxia.Meanwhile,the expression of nuclear transcription factor NF-kB p65 and pro-apoptotic protein Caspas3-cleaved was increased,the expression of anti-apoptotic protein Bcl-2 was decreased as compared with control group.We also found that the expression of miR-27 a was increased evidently after overexpression mi R-27 a and the expression of miR-27 a was increased significantly after silenting PPAR?.Compared to the luciferase activity of wild type,we found that miR-27 a mimic decreased luciferase activity of mi R-27 a binding sites significantly,but the luciferase activity of mutant miR-27 a binding sites had no obvious change.It suggested that PPAR? may be the target gene of mi R-27 a.Conclusions: MiR-27 a is closely related to the pathogenesis of cerebral ischemia by regulating its target gene PPAR? and influencing the expression of PPAR?-mediated apoptosis-related factors.