三七总皂苷对过氧化氢诱导的骨髓基质细胞凋亡的保护作用

目的：观察三七总皂苷（Panax notoginseng saponins，PNS）对过氧化氢诱导的兔骨髓基质细胞（bone marrow stromal cell，BMSC）凋亡的影响。方法：从2月龄新西兰兔获得原代BMSC，给予不同浓度PNS处理后，通过检测BMSC增殖能力和碱性磷酸酶活性观察BMSC早期成骨分化能力，筛选出PNS对BMSC作用的最佳浓度。采用过氧化氢（100 μmol/L）诱导BMSC凋亡。PNS对过氧化氢诱导前的BMSC进行预处理后，应用2′,7′-二氯荧光黄双乙酸盐法检测细胞活性氧水平，流式细胞术检测细胞凋亡率，免疫印迹法检测BMSC内Bax蛋白水平，荧光分光光度计检测BMSC内半胱氨酸天冬氨酸特异性蛋白酶3（caspase-3）活性。结果：PNS作用的最佳浓度是0.1 g/L。与单纯过氧化氢处理组相比，0.1 g/L PNS预处理能减少过氧化氢诱导后BMSC内的活性氧含量的升高，降低BMSC凋亡率，减少Bax蛋白表达，并降低caspase-3活性（P〈0.01）。结论：PNS可能通过减少氧化应激反应、Bax表达及caspase-3活性发挥其对过氧化氢诱导BMSC凋亡的保护作用。

Panax notoginseng saponins protect rabbit bone marrow stromal cells from hydrogen peroxide-induced apoptosis

Objective: To investigate the effects of Panax notoginseng saponins (PNSs) on hydrogen peroxide-induced apoptosis in rabbit bone marrow stromal cells (BMSCs).Methods: BMSCs were isolated from 2-month-old New Zealand rabbits and cultured with different doses of PNSs to determine the most effective dose of PNSs by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and alkaline phosphatase (ALP) assay. The most effective dose of PNSs was used in subsequent experiments. Apoptosis of BMSCs was induced by hydrogen peroxide (100 μmol/L). BMSCs in PNSs group were also pretreated with PNSs before hydrogen peroxide exposure. Reactive oxygen species (ROSs) levels were measured by using 2′,7′-dichlorodihydrofluorescein diacetate. Apoptosis rate of BMSCs was observed by flow cytometry after staining with Annexin V-fluorescein isothiocyanate/propidium iodide. The protein expression of Bax in BMSCs was analyzed by Western blotting. Activity of caspase-3 was measured by spectrofluorometry. Results: The most effective dose of PNSs was 0.1 g/L. PNSs at dose of 0.1 g/L markedly reversed the augmentation of ROS level, decreased the apoptosis rate of, and the Bax expression and activity of caspase-3 in BMSCs treated with hydrogen peroxide (P<0.01).Conclusion: PNSs can protect cultured rabbit BMSCs from hydrogen peroxide-induced apoptosis by decreasing oxidative stress, Bax expression and caspase-3 activity.