丹参素对缺氧/缺糖损伤神经细胞线粒体的保护作用

目的观察丹参素对SH-SY5Y细胞缺氧/缺糖损伤时胞浆内Ca2 ]i、细胞凋亡率、细胞活性和线粒体膜电位的变化,探讨其对神经细胞线粒体的保护作用及其可能的机理.方法应用细胞培养、四唑盐比色实验(MTT)检测细胞活力,流式细胞术检测细胞内Ca2 ]i、细胞凋亡百分率和线粒体膜电位.结果 SH-SY5Y细胞缺氧/缺糖损伤2 h时,细胞内Ca2 ]i明显增加,为8.46 nmol/L(P<0.01),细胞凋亡率明显增高,为18.59% (P<0.01),细胞内Ca2 ]i的浓度4 h时达到高峰,为9.89 nmol/L(P<0.01),而后呈下降趋势,细胞凋亡率随缺氧/缺糖损伤时间的延长而明显增高12 h时达到45.91%,细胞经缺氧/缺糖处理2 h后,线粒体膜电位和细胞活性分别降低29.17%(P<0.01)、38.80%(P<0.01),随着缺氧/缺糖时间的延长线粒体膜电位和细胞活性进一步下降, 12 h时分别降低56.72%(P<0.01)、63.58%(P<0.01),丹参素能显著降低细胞内Ca2 ]i,抑制细胞凋亡的发生,提高细胞活性和线粒体膜电位,与缺氧/缺糖组相比均有显著性差异(P<0.05,P<0.01).结论丹参素可抑制缺氧/缺糖损伤所致的线粒体膜电位的降低,从而具有稳定线粒体膜电位的作用,抑制细胞凋亡的发生,这种作用可能与其能抑制神经细胞内钙超载有关.

Protective Effects of Danshensu on the Mitochondria in the Nerve Cells Injured by Hypoxia/Hypoglycemia

Objective To observe the changes in Ca 2+ ]i, apoptotic rate, cell activity and mitochondrial membrane potential when Danshensu (3,4-dihydroxyphenyllactic acid) was administered to the SH-SY5Y cells injured by hypoxia/hypoglycemia, and to investigate the possible mechanism of the protective effects of Danshensu on the mitochondria of the nerve cells.Methods The cell cultivation techniques and MTT colorimetric test were used to examine cell activity; and the flow cytometry was used to detect the Ca 2+ ]i, apoptotic percentage and mitochondrial membrane potential.Results The Ca 2+ ]i increased markedly, reaching to 8.46 nmol/L (P<0.01); and the apoptotic rate increased remarkably, being 18.59% (P<0.01), in the SH-SY5Y cells after being with hypoxia/hypoglycemia for 2 hours.After 4 hours of hypoxia/hypoglycemia, the Ca 2+ ]i reached the peak, 9.89 nmol/L (P<0.01), and after that, it tended to decrease. The apoptotic rate increased markedly along with the prolonging of the duration in which the cells were with hypoxia/hypoglycemia, and the rate was 45.91% when hypoxia/hypoglycemia lasted for 12 hours. The mitochondrial membrane potential and cell activity decreased to 29.17% (P<0.01) and 38.80% (P<0.01), respectively after 2 hours of hypoxia/hypoglycemia; they further decreased along with the prolonging of the time of hypoxia/hypoglycemia, being 56.72% (P< 0.01) and 36.58% (P<0.01), respectively when hypoxia/hypoglycemia lasted for 12 hours. Danshensu was found to markedly decrease Ca 2+ ]i, inhibited the onset of apoptosis and increase mitochondrial membrane potential and cell activity (P<0.05 to 0.01).Conclusion Danshensu exerts a stabilizing effect on mitochondrial membrane potential by inhibiting the decrease in mitochondrial membrane potential due to hypoxia/hypoglycemia. It also inhibits the onset of apoptosis, which may be related with its effect for inhibiting the calcium overload in nerve cells.