miR-34a在幼鼠海马神经元细胞增殖和凋亡中的作用

目的:探讨miR-34a在幼鼠海马神经元细胞增殖凋亡中的作用。方法:分离幼鼠海马神经元细胞,转染miR-34a抑制剂(miR-34a inhibitor)、抑制剂对照(inhibitor control)、miR-34a模拟物(miR-34a mimics)、模拟物对照(mimics control),RT-PCR检测细胞中miR-34a表达水平。MTT检测转染后细胞增殖情况。流式细胞仪检测细胞凋亡情况。Western blot检测细胞中Cleaved-caspase-3、Bcl-2、Bax的表达水平。结果:转染miR-34a inhibitor可以抑制miR-34a的表达,miR-34a mimics可以促进miR-34a的表达。miR-34a mimics对细胞增殖抑制率明显高于mimics control组(P0.05),miR-34a inhibitor组抑制率明显低于inhibitor control组(P0.05)。miR-34a inhibitor组神经元细胞凋亡率明显低于inhibitor control组(P0.05),miR-34a mimics组神经元细胞凋亡率明显高于mimics control组(P0.01),inhibitor control组和mimics control组神经元细胞凋亡率差异不显著(P0.05)。miR-34a inhibitor组Cleaved-caspase-3、Bax蛋白表达量低于inhibitor control组,差异显著(P0.05);miR-34a inhibitor组Bcl-2蛋白表达量高于inhibitor control组,差异显著(P0.05);miR-34a mimics组Cleaved-caspase-3、Bax蛋白表达量高于mimics control,差异显著(P0.05);miR-34a mimics组Bcl-2蛋白表达量低于mimics control,差异显著(P0.05)。结论:miR-34a抑制海马神经元细胞增殖,促进细胞凋亡,其作用机制可能与调控Cleaved-caspase-3、Bcl-2、Bax表达有关。

Effects of miR-34a on Proliferation and Apoptosis of Hippocampal Neuronal Cell from Rats

ABSTRACT Objective: To investigate the role of miR-34a on proliferation and apoptosis of hippocampal neurons cell. Methods: Isolated rats hippocampal neurons were transfected with miR-34a inhibitor, inhibitor control, miR-34a mimics, mimics control, respectively. RT-PCR was used to detect the expression level of miR-34a, and MTT was used to detect cell proliferation. Apoptosis was detected by flow cytometry. Western blot analysis was determined the expression levels of Cleaved-caspase-3, Bcl-2, Bax. Results: Transfection with miR-34a inhibitor could inhibit the expression of miR-34a, miR-34a mimics could promote the expression of miR-34a.The cell proliferation inhibition rate in miR-34a mimics group was significantly higher than that of mimics control group (P <0.05), and the inhibition rate in miR-34a inhibitor group was significantly lower than that of inhibitor control group (P <0.05). The neuronal apoptosis in miR-34a inhibitor group was significantly lower than that of inhibitor control group (P <0.05), and the neuronal apoptosis was significantly higher in miR-34a mimics group than that of mimics control group (P <0.01). The neuronal apoptosis rate was not significantly different between inhibitory control group and mimics control group (P> 0.05). The cleaved-caspase-3, Bax protein expression level lower in miR-34a inhibitor group than that of inhibitor control group, and the difference was significant (P <0.05); and Bcl-2 protein expression was higher in miR-34a inhibitor group than that of inhibitor control group, and the difference was significant (P <0.05). The cleaved-caspase-3, Bax protein expression was higher in miR-34a mimics group than that of mimics control with statistical significance (P <0.05); and Bcl-2 protein expression of miR-34a mimics group was lower than that of mimics control (P <0.05). Conclusion: miR-34a can inhibit proliferation of hippocampal neurons and promote neuronal apoptosis, and its mechanism may be related to Cleaved-caspase-3, Bcl-2, Bax.