中文摘要：

Neural stem cells(NSCs) proliferation can be influenced by repetitive transcranial magnetic stimulation(r TMS) in vivo via micro RNA-106b-25 cluster,but the underlying mechanisms are poorly understood. This study investigated the involvement of micro RNA-106b-25 cluster in the proliferation of NSCs after repetitive magnetic stimulation(r MS) in vitro. NSCs were stimulated by r MS(200/400/600/800/1000 pulses per day,with 10 Hz frequency and 50% maximum machine output) over a 3-day period. NSCs proliferation was detected by using ki-67 and Ed U staining. Ki-67,p21,p57,cyclin D1,cyclin E,cyclin A,cdk2,cdk4 proteins and mi R-106 b,mi R-93,mi R-25 m RNAs were detected by Western blotting and q RT-PCR,respectively. The results showed that r MS could promote NSCs proliferation in a dose-dependent manner. The proportions of ki-67+ and Edu+ cells in 1000 pulses group were 20.65% and 4.00%,respectively,significantly higher than those in control group(9.25%,2.05%). The expression levels of mi R-106 b and mi R-93 were significantly upregulated in 600–1000 pulses groups compared with control group(P<0.05 or 0.01 for all). The expression levels of p21 protein were decreased significantly in 800/1000 pulses groups,and those of cyclin D1,cyclin A,cyclin E,cdk2 and cdk4 were obviously increased after r MS as compared with control group(P<0.05 or 0.01 for all). In conclusion,our findings suggested that r MS enhances the NSCs proliferation in vitro in a dose-dependent manner and mi R-106b/p21/cdks/cyclins pathway was involved in the process.

英文摘要：

Neural stem cells（NSCs） proliferation can be influenced by repetitive transcranial magnetic stimulation（r TMS） in vivo via micro RNA-106b-25 cluster,but the underlying mechanisms are poorly understood. This study investigated the involvement of micro RNA-106b-25 cluster in the proliferation of NSCs after repetitive magnetic stimulation（r MS） in vitro. NSCs were stimulated by r MS（200/400/600/800/1000 pulses per day,with 10 Hz frequency and 50% maximum machine output） over a 3-day period. NSCs proliferation was detected by using ki-67 and Ed U staining. Ki-67,p21,p57,cyclin D1,cyclin E,cyclin A,cdk2,cdk4 proteins and mi R-106 b,mi R-93,mi R-25 m RNAs were detected by Western blotting and q RT-PCR,respectively. The results showed that r MS could promote NSCs proliferation in a dose-dependent manner. The proportions of ki-67＋ and Edu＋ cells in 1000 pulses group were 20.65% and 4.00%,respectively,significantly higher than those in control group（9.25%,2.05%）. The expression levels of mi R-106 b and mi R-93 were significantly upregulated in 600–1000 pulses groups compared with control group（P〈0.05 or 0.01 for all）. The expression levels of p21 protein were decreased significantly in 800/1000 pulses groups,and those of cyclin D1,cyclin A,cyclin E,cdk2 and cdk4 were obviously increased after r MS as compared with control group（P〈0.05 or 0.01 for all）. In conclusion,our findings suggested that r MS enhances the NSCs proliferation in vitro in a dose-dependent manner and mi R-106b/p21/cdks/cyclins pathway was involved in the process.