人参皂苷Rg_1在造血干/祖细胞连续移植中抗细胞衰老的作用机制

Mechanism of ginsenoside Rg_1 against hematopoietic stem/progenitor cells senescence during serial transplantation

目的探讨人参皂苷Rg1在造血干/祖细胞(HSC/HPC)连续移植中抗细胞衰老的作用机制。方法免疫磁性分选法分离纯化的雄性供体小鼠Sca-1+HSC/HPC连续移植3代构建HSC/HPC衰老体内模型。经60Coγ射线致死剂量辐射的雌性受体小鼠分成4组:对照组、模型组、人参皂苷Rg1(20 mg/kg)治疗给药组、人参皂苷Rg1(20 mg/kg)预防给药组,每天给药1次,连续给药30 d。荧光定量PCR法检测各组小鼠Sca-1+HSC/HPC p16INK4a、p19Arf、p53、p21Cip1/Waf1基因的表达,Western blotting法检测p16INK4a、p21Cip1/Waf1、CDK4、CDK2、CyclinD1、Cyclin E蛋白的表达。结果与模型组比较,各代移植Sca-1+HSC/HPC雌性小鼠中,人参皂苷Rg1治疗给药组及预防给药组小鼠Sca-1+HSC/HPC p16INK4a、p19Arf、p53、p21Cip1/Waf1基因及p16INK4a、p21Cip1/Waf1、CyclinD1蛋白表达下调;CDK4、CDK2、CyclinE蛋白表达上调。人参皂苷Rg1预防给药组小鼠各项检测指标的改善均优于其治疗给药组。结论人参皂苷Rg1可能通过调控p16INK4a-Rb和p19Arf-p53-p21Cip1/Waf1信号转导通路,对Sca-1+HSC/HPC连续移植衰老模型发挥拮抗作用。

Objective To investigate the mechanism of ginsenoside Rg1 against the hematopoietic stem/progenitor cell （HSC/HPC） senescence during serial transplantation. Methods Male mice Sca-1＋HSC/HPC isolated and purified by magnetic activated cell sorting （MACS） were transplanted for three generations to establish aging in vivo model of mice. The female recipient mice radiated lethal dose from 60Co γ ray were divided into four groups： the control, model, Rgl-treated （20 mg/kg）, and RgI prevention （20 mg/kg） groups. The mice were administered once daily for 30 d. The expression of p 16INK4a, p 19Arf, p53, and p21Cipl/Wafl mRNA was detected by quantitative PCR. The expression of p16INK4a, p21Cipl/wafl, CDK4, CDK2, CyclinD1, and CyclinE proteins was examined by Western blotting. Results Compared with the model group, the expression ofp16INK4a, p19Arf, p53, p21Cipl/Wafl mRNA and pl6INK4a, p21Cipl/Wafl, CyclinD1 proteins was down-regulated, and the expression of CDK4, CDK2, and CyclinE proteins was up-regulated in both Rg1-treated and Rg1 prevention groups. The all index changes of mice in Rg1 prevention group were significantly higher than those of mice in Rgl-treated group. Conclusion Rgl could prevent and treat the Sca-1＋HSC/HPC senescence during serial transplantation in which the signaling pathways of p16INK4a-Rb and p19Arfp53-p21cip/Wafl may play an important role.