三丁基过氧化氢体外诱导造血干/祖细胞衰老中的SIRT6/NF-κB信号轴

背景：SIRT6/NF-κB信号轴是细胞衰老的调控通路，但其在造血干/祖细胞（hematopoietic stem and progenitor cel ，HSC/HPC）衰老中的作用尚不清楚。目的：探讨SIRT6/NF-κB信号通路在三丁基过氧化氢体外诱导造血干/祖细胞衰老中的作用。方法：免疫磁性分选法分离、纯化小鼠Sca-1＋ HSC/HPC。用100μmol/L三丁基过氧化氢体外诱导Sca-1＋HSC/HPC构建体外衰老模型，通过衰老相关β-半乳糖苷酶细胞化学染色、流式细胞术分析细胞周期、造血祖细胞混合集落培养确定三丁基过氧化氢诱导 Sca-1＋HSC/HPC 衰老的生物学作用。荧光定量 PCR 及Western blotting检测衰老调控分子SIRT6、NF-κB mRNA及蛋白的表达。结果与结论：与对照组比较，衰老组Sca-1＋ HSC/HPC β-半乳糖苷酶染色阳性细胞数、G0/G1期细胞比例增高，形成造血祖细胞混合集落数量减少；SIRT6 mRNA及蛋白表达下调，NF-κB mRNA及蛋白表达上调。结果表明三丁基过氧化氢可能通过调控SIRT6/NF-κB信号通路发挥诱导Sca-1＋HSC/HPC衰老作用。

Effect of SIRT6/NF-kappa B signal axis during hematopoietic stem and progenitor cell senescence induced by tert-butylhydroperoxide in vitro

BACKGROUND：SIRT6/NF-κB is the important signal axis to cellsenescence, but the effect of SIRT6/NF-κB signal axis to hematopoietic stem and progenitor cell（HSC/HPC） senescence is unclear. OBJECTIVE：To induce （t-BHP） in vitro and to investigate the role of SIRT6/NF-κB signal axis in Sca-1＋HSC/HPC senescence induced by tert-butylhydroperoxide in vitro. METHODS：Sca-1＋HSC/HPC was isolated and purified by magnetic activated cellsorting. Sca-1＋HSC/HPC senescence was induced by 100μmol/L tert-butylhydroperoxide in vitro. The senescence-associatedβ-Galactosidase staining, cellcycle analysis and culture of mixed hematopoietic progenitor cellwere used to investigate the biological effects of tert-butylhydroperoxide on Sca-1＋HSC/HPC senescence. The expression of senescence associated SIRT6, NF-κB mRNA and protein was examined by real-time fluorescence quantitative PCR and western blot assay. RESULTS AND CONCLUSION：Compared with control group, the percentage of positive cells expressing SA-β-Gal and cells in G0/G1 phase increased and the number of forming colony of mixed hematopoietic progenitor decreased in the aging group. It showed lower expression of SIRT6 and higher expression of NF-κB in the aging group. The SIRT6/NF-κB signal axis may play a key role in the Sca-1＋ HSC /HPC senescence inducted by tert-butylhydroperoxide.