微小RNA-320在缺氧诱导的大鼠神经细胞中的表达和功能研究

Expression and function of miR-320 in hypoxia-induced rat nerve cells

目的研究微小RNA-320(microRNA-320,miR-320)在缺氧诱导的大鼠PC12细胞的表达特征,并探讨其对PC12细胞增殖和凋亡的影响。方法采用荧光定量PCR检测常氧组和缺氧诱导组PC12细胞中miR-320表达情况;转染miR-320 mimics(实验组)和mimics control(对照组)至缺氧诱导的PC12细胞,采用细胞增殖实验和ELISA法观察细胞增殖和凋亡情况。结果缺氧诱导组PC12细胞中miR-320表达显著低于常氧组(0.27±0.14vs 1.01±0.21,P<0.05)。实验组细胞内源性miR-320表达显著高于对照组(6.57±0.92 vs 1.54±0.21,P<0.05)。对照组PC12细胞24、48和72h增殖率分别为(11.57±3.21)%、(14.39±3.57)%和(17.28±4.49)%,实验组分别为(19.15±4.02)%、(24.20±5.12)%和(29.36±5.78)%。对照组PC12细胞中Bcl-2、Bax和半胱氨酸天冬氨酸蛋白酶3的表达量分别为(1.67±0.52)μg/L、(2.15±0.24)μg/L和(4.66±0.79)μg/L,实验组分别为(3.01±0.77)μg/L、(0.33±0.04)μg/L和(1.59±0.46)μg/L,2组比较有显著差异(P<0.05)。结论 miR-320在缺氧诱导大鼠PC12细胞呈现低表达,体外升高其表达具有促进缺氧诱导PC12细胞增殖并抑制凋亡的功能。

Objective To study the effect of miR-320 expression on the proliferation and apoptosis of hypoxia-induced rat PC12 cells.Methods The PC12 cells were divided into normal oxygen group,hypoxia group,experimental group and control group.The expression of miR-320 in PC12 cells was detected by quantitative RT-PCR.The proliferation and apoptosis of PC12 cells transfected with miR-320 mimics or mimics control were detected by MTT assay and ELISA.ResultsThe expression level of miR-320 was significantly lower in hypoxia group than in normal oxygen group（0.27±0.14 vs 1.01±0.21,P〈0.05）and in experimental group than in control group（6.57±0.92 vs 1.54±0.21,P〈0.05）.The proliferation rate of PC12 cells was 11.57% ±3.21%,14.39% ±3.57%,17.28% ±4.49% respectively in control group and was 19.15%±4.02%,24.20%±5.12%,29.36%±5.78%respectively in experimental group at 24,48 and 72 h after transfected with mimics control.The expression level of Bcl-2,Bax and caspase-3 was 1.67±0.52μg/L,2.15±0.24μg/L,4.66±0.79μg/L respectively in control group and was 3.01±0.77μg/L,0.33± 0.04μg/L,1.59±0.46μg/L respectively in experimental group.Conclusion The expression of miR-320 is down-regulated in hypoxia-induced rat PC12 cells.Elevated in vitro expression of miR-320 can promote the proliferation and inhibit the apoptosis of PC12 cells.