miRNA-132在癫痫大鼠模型中的作用及意义

Role and significance of miRNA-132 in rat epilepsy model

[目的]探讨miRNA-132对颞叶癫痫大鼠脑组织海马神经元的凋亡及保护作用及其机制.[方法]选择雄性SD大鼠随机分为正常组、癫痫组、agomir-132组和antagomir-132组.建立模型前采用脑立体定位仪向大鼠海马区注射给予agomir-132和antagomir-132,正常组和癫痫组注射给予生理盐水.取脑及海马组织,HE染色观察各组海马组织的病理学变化,利用实时荧光定量PCR法检测各组海马组织中miRNA-132的含量,采用Western blot法及免疫组织化学染色法检测各组海马组织中凋亡相关蛋白Bcl-2、Bax及Caspase-3的表达水平.[结果]与正常组比较,癫痫大鼠miRNA-132含量均升高;与癫痫组比较,agomir-132组miRNA-132含量显著升高(P<0.01),而antagomir-132组miRNA-132含量明显降低(P<0.05).与正常组比较,癫痫组、agomir-132组及antagomir-132组海马组织中Bcl-2表达水平显著降低,Bax、Caspase-3表达水平均显著升高;与癫痫组比较,agomir-132组Bcl-2表达水平显著降低,Bax、Caspase-3表达水平均显著升高,antagomir-132组Bcl-2表达水平显著升高,Bax、Caspase-3表达水平均显著降低;相比较差异均有统计学意义(P<0.05,P<0.01).[结论] miRNA-132在癫痫大鼠海马组织中含量显著升高,antagomir-132可能通过调控癫痫大鼠海马中的凋亡因子而减弱神经元细胞的损伤,agomir-132通过使凋亡因子增多来加速神经元细胞的凋亡.

OBJECTIVE To explore the protective effect and mechanism of miRNA-132 on apoptosis of hippocampal neuron in rats with temporal lobe epilepsy.METHODS Male SD rats were randomly divided into normal group,epilepsy group,agomir-132 group and antagomir-132 group.Before establishing the model,agomir-132 and antagomir-132 were injected into the hippocampus of rats with brain stereotaxic apparatus,and normal group and epilepsy group were injected with normal saline.The brain and hippocampus tissues were collected,and the pathological changes of the hippocampus tissues were observed by HE staining.The contents of miRNA-132 in the hippocampus tissues of each group were detected by real-time fluorescence quantitative PCR.Western blot and immunohistochemical staining method were used to detect the expression levels of apoptosis-related proteins Bcl-2,Bax and Caspase-3 in the hippocampus tissues of each group.RESULTS The content of miRNA-132 in epileptic rats was increased compared with normal group.Compared with epilepsy group,miRNA-132 content in agomir-132 group was significantly increased(P<0.01),while miRNA-132 content in antagomir-132 group was obviously decreased(P<0.05).Compared with normal group,the expression levels of Bcl-2 in hippocampus of epilepsy group,agomir-132 group and antagomir-132 group were significantly decreased,while the expression levels of Bax and Caspase-3 were significantly increased.Compared with epilepsy group,the expression level of Bcl-2 in agomir RNA-132 group was significantly decreased,while the expression levels of Bax and Caspase-3 were significantly increased,the expression level of Bcl-2 in antagomir-132 group was significantly increased,while the expression levels of Bax and Caspase-3 were significantly decreased,the differences were statistically significant(P<0.05,P<0.01).CONCLUSION The content of mi RNA-132 was obviously increased in hippocampus of epileptic rats.Antagomir-132 may weaken the damage of neurons by regulating apoptosis factors in hippocampus of epileptic rats,and agomir-132 may accelerate the apoptosis of neurons by increasing apoptosis factors.