亚硒酸钠通过AMPK/mTOR通路调控白血病NB4细胞凋亡

摘要

Objective To explore the effect of sodium selenite on AMPK/mTOR signaling pathway and its regulation of apoptosis in leukemia cells NB4. Methods NB4 cells were treated with sodium selenite with different concentrations or in a time dependent manner, then the phosphorylation level of AMPK, mTOR and P70S6K were detected by Western blot. To investigate the effect of AMPK on mTOR and apoptosis in NB4, cells were treated by AMPK activator AICAR and siRNA which targeted AMPK. The phosphorylation level of AMPK, mTOR and P70S6K were detected by Western blot, and apoptotic rates were analyzed by Annexin V/PI double staining. The interaction between AMPK and mTOR was evaluated by co-immunoprecipitation assay. Results Sodium selenite can activate AMPK, inhibit mTOR and promote apoptosis in NB4 cells. When NB4 cells were treated with AICAR alone, an activator of AMPK, apoptosis was induced which was similar to that of selenite. When AMPK was knocked down with specific siRNA, phosphorylation of mTOR and P70S6K increased and selenite-induced apoptosis was attenuated in NB4 cells. Results of co-immunoprecipitation show there is a direct interaction between AMPK and mTOR. Conclusions Sodium selenite can activate AMPK, inhibit mTOR and P70S6K, thus promotes apoptosis in NB4 cells.%目的 研究亚硒酸钠对白血病NB4细胞中AMPK及其下游靶蛋白对细胞凋亡的调控作用.方法 分别用亚硒酸钠、AICAR和AMPK干扰序列处理NB4细胞.用Western blot检测细胞AMPK、mTOR及其下游蛋白P70S6K的磷酸化水平及激活和干扰AMPK后AMPK、mTOR及P70S6K的磷酸化水平、流式细胞术检测NB4细胞凋亡率；免疫共沉淀法检测AMPK和mTOR的相互作用.结果 亚硒酸钠可以上调NB4细胞中AMPK的磷酸化水平,下调mTOR及P70S6K的磷酸化水平；AICAR和亚硒酸钠单独处理具有类似的促进NB4细胞凋亡的效果；干扰AMPK后,mTOR及P70S6K的磷酸化水平上升,亚硒酸钠对NB4细胞的促凋亡作用被拮抗；AMPK和mTOR有直接相互作用.结论 亚硒酸钠可通过激活AMPK表达,抑制mTOR及P70S6K,促进NB4细胞凋亡.