SIRT1/NF-κB信号轴在人参皂苷Rg_1延缓D-半乳糖致衰老模型大鼠造血干/祖细胞衰老过程中的作用

Effect of SIRT1/NF-κB signal axis on delaying hematopoietic stem cell and progenitor cell senescence with ginsenoside R_1 in aging model rat induced by D-galactose

目的探讨SIRT1／NF-κB信号轴在人参皂苷Rgl对抗衰老模型大鼠造血干／祖细胞衰老中的作用。方法6～8周雄性SD大鼠50只，随机分为对照组、模型组、人参皂苷Rgl对照组、人参皂苷Rgl治疗组和人参皂苷Rg，预防组，每组10只。以连续42 d sc D-半乳糖（D-gal）制备衰老动物模型，人参皂苷Rg1各组ip给药不同时间，药物注射完成第2天，免疫磁性分选法分离纯化各组Sca-1^＋造血干／祖细胞（HSC／HPC），衰老相关β-半乳糖苷酶（SA-β-Gal）染色、流式细胞周期分析和造血祖细胞混合集落（CFU-Mix）培养观察人参皂苷Rg1对Sca-1^＋ HSC／HPC抗衰老的生物学作用。荧光定量PCR及Western blotting检测衰老调控分子SIRTl、NF-κB mRNA及蛋白的表达。结果与模型组比较，人参皂苷Rgl治疗组和预防组SA-β-Gal染色阳性率、G0／G1期细胞比例下降，生成CFU-Mix数增高，SIRTlmRNA及蛋白表达上调，NF-κB mRNA及蛋白表达下调；人参皂苷Rgl预防组各指标变化均较人参皂苷Rgl治疗组明显。结论SIRTl／NF-κB信号轴在人参皂苷Rgl对抗D-gal致衰老模型大鼠HSC／HPC衰老过程中发挥重要作用，人参皂苷Rgl具有抗HSC／HPC衰老作用。

Objective To investigate the effect of SIRT1/NF-κB signal axis on delaying hematopoietic stem cell and progenitor cell senescence with ginsenoside Rgl in ageing model rat induced by D-galactose. Methods Male SD rats （n = 40） aging from 6 to 8 weeks old were randomly divided into control group, aging model group, positive control group, RgI treated group, and RgI prevented group （n = 10）. The aging rat model was prepared by sc D-galactose for continuous 42 d, then ginsenoside Rg1 was given in different time. After 2 d of the treatment, the Sca-1^＋ HSC/HPC was isolated by magnetic cell sorting （MACS）. The changes of cells observed by senescence-associated β-galactosidase （SA-β-Gal） staining, cell cycle analysis and culture of mixed hematopoietic progenitor cell were used to investigate the treated aging effect of ginsenoside Rgl.The expression of senescence associated SIRT1, NF-κB mRNA and protein was examined by real time fluorescence quantitative PCR （FQ-PCR） and Western blotting. Results In ginsenoside Rg1 treated group and ginsenoside Rgl prevented group, the percentage of positive cells expressed SA-β-Gal and the number of cells entering G0/G1 phase were lower than that of aging model group, but the number of CFU-Mix was increased than aging model group. Compared with aging model group, the expression of SIRT1 mRNA and protein was upregulated and the expression of NF-κB mRNA and protein was downregulated in Rgl treated group and prevented group. Changes in Rgl prevented group were more than those in Rgl treated group. Conclusion SIRT1/NF-κB signal axis may play a key role in the anti-aging effect of Rgl to Sca-1 HSC/HPC senescenc in ageing model rat induced by D-galactose.