低频磁刺激对人神经干细胞生长和分化的影响

Early treatment with high-volume hemofiltration combined with rhubarb for patients with severe acute pancreatitis

目的:探讨体外不同条件的磁刺激对神经干细胞细胞增殖、细胞周期、细胞凋亡和细胞分化等方面的影响。方法:对离体人胚神经干细胞进行磁刺激处理,采用频率0.5 Hz,脉冲刺激波宽为72μs,刺激强度为阈上刺激1.44 T,每天1次,连续刺激3 d。按刺激次数分为A组(30个脉冲刺激/次)、B组(60个脉冲刺激/次)、C组(90个脉冲刺激/次)、D组(对照组,不进行磁刺激处理);用四甲基偶氮唑盐(MTT)法检测磁刺激对神经干细胞增殖的作用;用流式细胞术检测磁刺激对神经干细胞的细胞周期、细胞凋亡和细胞分化的作用。结果:A、B、C组神经干细胞在接受磁刺激后24～48 h的D值较D组明显增高(P<0.05),提示磁刺激对神经干细胞有轻度促增殖作用;A、B、C组G0/G1期细胞比例稍低于D组,而相应的G2/M比例较高,但无统计学差异;A、B、C组β-tuberlin阳性细胞比例较D组高,神经元比例由21.70%上升至34.17%(P<0.05)。结论:磁刺激在轻度促进细胞增殖的条件下,可诱导神经干细胞向神经元方向分化,有利于神经功能重建。

Objective：To investigate the effects of different magnetic simulations on cell proliferation, cell cycle, apoptosis, and cell differentiation of human fetal neural stem cell in vitro. Methods： Isolated neural stem cells were exposed to magnetic stimulation （with a frequency of 0.5 Hz, a wave wide of 72 μs and an intensity of 1.44 Tesla） once daily for 3 days. The cells were divided into three groups according to the pulses of magnetic stimulation each time： A group （thirty pulses each time）, B group （sixty pulses each time）, C group （ninety pulses each time） and D group （control group）. MTT assay was applied to detect the proliferation activity of the neural stem cells, and flow cytometry was employed to detect the effect of magnetic stimulation on cell cycle, cell apoptosis, and cell differentiation. Results： The D values of neural stem cells in A, B, and C groups were significantly higher than those in the control group 24 to 48 hours after stimulation（P〈0.05）, indicating a slightly promoted proliferation of neural stem cells after magnetic stimulation. The proportions of G0/G1 phase cells of A, B, and C groups were less than those of the control group, and the proportion of G2/M-phase cells was higher than that of the control group. The proportions of β-tuberlin positive neurons in A, B, and C groups were higher than those in the control group as demonstrated by flow eytometry, and the proportion of neurons increased from 21. 70% to 34. 17% （P〈0.05）. Conclusion： Under proper condition, magnetic simulation can slightly promote cell proliferation and can induce neural stem cell differentiation into neurons in vitro, which may benefit neural function reconstruction.