【摘要】 目的:探讨白藜芦醇(RES)抑制白血病K562细胞增殖的机制及非折叠蛋白应答(UPR)对其机制的影响。方法:选取不同浓度的RES干预K562细胞,并且用RES(100μmol/L)干预K562细胞不同时段;利用MTT法检测细胞存活率;利用流式细胞仪分析细胞周期并检测细胞凋亡率;利用蛋白质印迹法检测凋亡早期蛋白及UPR靶点蛋白表达水平;利用实时定量PCR法检测GRP78和CHOP mRNA的表达。结果:RES导致K562细胞细胞存活率明显减少,并呈剂量依赖方式;RES的生长抑制作用主要是阻断细胞周期中的G1期,G2/M期的变化较小;RES处理的K562细胞没有显著的细胞凋亡。RES可提高GRP78mRNA的表达水平,呈剂量及时效依赖方式;RES对CHOP mRNA水平也有诱导作用,但只有在RES浓度较大时(50μmol/L)或作用时间较长时(8h)才开始上调,并且上调幅度较小。蛋白质印迹分析证实RES提高UPR靶点(GRP78、GRP94、磷酸化eIF2a和剪接作用XBP-1)的蛋白表达水平。结论:RES优先诱导UPR存活分支,表明UPR参与RES抑制白血病K562细胞增殖的机制。更多还原

【Abstract】 OBJECTIVE:To investigate whether unfolded protein response(UPR) involved in mechanisms underlying resveratrol-induced inhibition of K562 cell proliferation.METHODS: K562 cells were treated with different concentration of resveratrol,and 100 μmol/L of resveratrol were selected for treating K562 cells with different period;3-(4,5-dimethylthiahiazo-2-thiazolyl)-2,5-diphenyl tetrazolium bromide(MTT) assay was used for cell viability assays;Analysis of the cell cycle or detection of cell death was confirmed by flow cytometry;marked protein of early apoptosis phase and UPR targets were detected by western blot analysis;the expression of GRP78 and CHOP mRNA were measured by real-time RT-PCR.RESULTS: Exposure of K562 leukemia cells to RES resulted in a marked reduction of cell viability in a dose-dependent manner;the growth inhibitory effect of RES was the result of a block of cell cycle primarily at G1 phase,to a lesser extent at G2/M phase.Remarkable apoptosis in RES-treated K562 cells was not observed.RES-induced GRP78 expression in a dose-dependent manner;After longer period(8 h) or larger concentrations(50 μmol/L) of RES exposure,CHOP mRNA levels was also upregulated,but with rather minor degree.Several targets of UPR including GRP78,GRP94,phosphorylated eIF2a and splicing of XBP-1 were also demonstrated to be increased by western blot analysis.CONCLUSION: UPR involved in mechanisms underlying resveratrol-induced inhibition of K562 cell proliferation.更多还原