地榆皂苷Ⅰ基于自噬升高白细胞作用研究

Promotion of Ziyuglycoside Ⅰ on white blood cells by autophagy pathway

目的研究地榆皂苷Ⅰ(ZgⅠ)升高外周血液中白细胞数量的作用机制。方法昆明种小鼠按体质量随机分为对照组、模型组、3-甲基腺苷(3-MA)组、ZgⅠ(20 mg/kg)组、ZgⅠ(20 mg/kg)+3-MA组。实验第1天以120 mg/kg剂量ip环磷酰胺诱导小鼠骨髓抑制模型并ig给药,连续给药6 d。实验第6天采用全自动血球计数仪测定小鼠血液中白细胞和中性粒细胞数量;采用透射电镜和免疫荧光显微镜观察造血干细胞自噬程度;流式细胞仪测定造血干细胞凋亡率;Western blotting法检测Atg5、Atg7和Beclin-1蛋白表达水平。结果与模型组和3-MA组比较,ZgⅠ可显著升高骨髓抑制小鼠白细胞数量(P<0.05)和中性粒细胞数量(P<0.05),激发其造血干细胞自噬的发生,并显著上调造血干细胞中Atg5、Atg7和Beclin-1蛋白的表达水平(P<0.01)。结论 ZgⅠ是一种高效的自噬激活剂,其升高白细胞机制可能与促进骨髓抑制小鼠造血干细胞自噬有关。

Objective To study the mechanism of ziyuglycoside Ⅰ（ZgⅠ） increasing the number of white blood cells（WBC） in peripheral blood. Methods KM mice were randomly divided into control group, model group, 3-methyladenosine（3-MA） group, ZgⅠ group（20 mg/kg）, and ZgⅠ（20 mg/kg）＋3-MA group. On the first day of experiment, myelosuppression mice were induced by ip cyclophosphamide of 120 mg/kg and were continuously gavaged with ZgⅠ for 6 d. On the 6 th day, the number of WBC and granulocytes were determined. The degree of hematopoietic stem cells（HSCs） autophagy was observed by transmission electron microscopy and immunofluorescence microscopy. The apoptosis rate of HSCs was determined by flow cytometry, and the expression of Atg5, Atg7, and Beclin-1 proteins were detected by Western blotting. Results Compared with the model group and 3-methyladenine group, ZgⅠ significantly increased the numbers of leukocyte and granulocytes（P〈0.05）, it also significantly stimulated the autophagy of HSCs. Meanwhile, ZgⅠ significantly up-regulated the Atg5, Atg7, and Beclin-1（P〈0.01） proteins expression in HSCs. Conclusion The results suggested that ZgⅠ was an efficient autophagic activator, and the mechanism of increasing WBC might be related to the promotion of HSCs autophagy of myelosuppression mice.