miRNA-125a 靶向调控 Bcl-2 对癫痫大鼠神经元凋亡的影响

摘要:目的 探讨 miRNA-125a 靶向调控 Bcl-2 对癫痫大鼠神经元凋亡的影响。 方法 选择清洁级 SD 雄性大鼠32 只随机分为正常对照组( A 组) 、癫痫组( B 组) 、miRNA-125a antagomir control 组( C 组) 和 miRNA-125a antagomir组( D 组) 。 qRT-PCR 检测各组大鼠脑组织 miRNA-125a 表达水平;HE 检测各组大鼠脑海马组织 CA-1 区病理形态学改变;TUNEL 法检测脑海马 CA-1 区神经元细胞凋亡数;Western blot 和 qRT-PCR 法检测各组大鼠脑组织中 Bcl-2的表达水平;荧光素酶活性检测 miRNA-125a 与 Bcl-2 的靶向关系。 结果 与 A 组相比,B 组和 C 组大鼠脑组织miRNA-125a 表达升高,差异具有统计学意义( P<0. 05) ;A 组海马细胞排列整齐,细胞形态结构及层次清晰完整,核仁明显,间质无水肿;B 组可见坏死灶,细胞排列紊乱,细胞核固缩,核仁消失,细胞间隙增宽出现水肿;TUNEL 结果显示,B 组、C 组和 D 组脑海马神经元凋亡细胞数明显高于 A 组,而大鼠脑组织 Bcl-2 mRNA 及蛋白表达降低。 D 组miRNA-125a 表达与 C 组相比降低而 Bcl-2 表达增加( P<0. 05) ,且 D 组大鼠脑组织水肿现象明显减轻,海马细胞排列紊乱现象有所改善。 荧光素酶报告基因实验结果显示,miRNA-125a 和 Bcl-2 能够靶向结合。 结论 癫痫模型大鼠脑组织 miRNA-125a 可通过调控 Bcl-2 表达,进一步导致脑海马神经元损伤及大量神经元细胞凋亡;抑制 miRNA-125a 的表达水平可改善癫痫大鼠神经元损伤。

Effect of miRNA-125a Targeted Regulation of Bcl-2 on Neuronal Apoptosis in Epileptic Rats

Objective To investigate the effect of miRNA-125a targeting Bcl-2 on neuronal apoptosis in epileptic rats.Method Thirty two male SD rats were randomly divided into normal control group(group A),epilepsy group(group B),miRNA-125a antigomir control group(group G)and miRNA-125a antigomir group(group D).The expression level of miRNA-125a was detected by qRT-PCR.HE was used to detect the pathomorphological changes of CA-1 region in hippocampus in each group.TUNEL method was used to detect the apoptosis number of neurons in CA-1 region in hippocampal.Western blot and qRT-PCR were used to detect the expression of Bcl-2 in brain tissue of rats in each group.The targeting relationship between miRNA-125a and Bcl-2 was detected by luciferase activity.Result Compared with group A,the expression of miRNA-125a in brain tissue of group B and group C increased significantly(P<0.05).In group A,hippocampal cells were arranged orderly,cell morphology and structure were clear and complete,nucleolus was obvious,interstitial tissue had no edema;in group B,necrosis was seen,cell arrangement was disordered,nuclear pyknosis and nucleolus disappeared,cell gap widened and edema appeared.The result of TUNEL showed that the number of apoptotic cells in hippocampus of group B,C and D was significantly higher than that of group A,while the expression of Bcl-2 mRNA and protein was decreased.The expression of miRNA-125a in group D was lower than that in group C,while the expression of Bcl-2 in group D was higher than that in group C(P<0.05).The result of luciferase reporter gene experiment showed that miRNA-125a and Bcl-2 could target to combine.Conclusion The expression of miRNA-125a in brain tissue of epileptic rats can be further regulated by Bcl-2,which can further lead to brain horse neuron injury and a large number of neuron apoptosis;inhibition of miRNA-125a expression level can improve the neuron injury of epileptic rats.