DUSP1通过AMPK/mTOR/ULK1信号通路介导BCG诱导的巨噬细胞自噬

DUSP1 mediates BCG-induced macrophage autophagy via AMPK/mTOR/ULK1 signaling pathway

目的探讨双特异性磷酸酶1(dual-specificity phosphatase-1,DUSP1)对卡介苗(Bacillus Calmette-Guérin,BCG)感染引起的THP-1巨噬细胞自噬的调控作用。方法利用小干扰RNA技术建立DUSP1干扰巨噬细胞模型,BCG感染细胞后,通过Western blot、qRT-PCR、免疫荧光等技术检测DUSP1和自噬相关蛋白LC3-II、Beclin1、ATG5、ATG7、ATG12以及自噬相关信号通路关键蛋白p-AMPK、p-ULK1、p-mTOR的表达水平。结果BCG感染巨噬细胞后,可显著上调DUSP1和LC3-II的表达水平,并呈时间梯度依赖性(P<0.001);与BCG单独感染组相比,si-DUSP1+BCG组自噬相关蛋白LC3-II、Beclin1、ATG5、ATG7和ATG12的表达水平显著降低(P<0.001),自噬流减弱,同时,p-AMPK、p-ULK1的表达显著降低(P<0.001),而p-mTOR的表达水平则显著升高(P<0.001)。结论DUSP1可能通过AMPK/mTOR/ULK1通路促进BCG感染引起的细胞自噬。

This study was designed to investigate the role of dual-specificity phosphatase-1(DUSP1)in the regulation of autophagy in THP-1 macrophages induced by Bacillus Calmette-Guérin(BCG)infection.A model of DUSP1-interfering macrophages was established using small interfering RNA technology,which was then infected with BCG.Western blot,qRT-PCR and immunofluorescence were used to detect the expression levels of DUSP1and autophagy-related proteins LC3-II,Beclin1,ATG5,ATG7,ATG12,and key proteins of autophagy-related signaling pathway p-AMPK,p-ULK1,p-mTOR in the model cells.Data showed that BCG infection of macrophages upregulated the expression levels of DUSP1 and LC3-II in a time-gradient-dependent manner(P<0.001);compared with the BCG-infected group alone,the expression levels of autophagy-related proteins LC3-II,Beclin1,ATG5,ATG7 and ATG12 were significantly reduced in the si-DUSP1+BCG group(P<0.001),and autophagic flow was attenuated,the expression of p-AMPK and p-ULK1 were significantly reduced(P<0.001),while the p-mTOR expression level was significantly increased(P<0.001).Taken together,DUSP1 may promote BCG infectioninduced cellular autophagy via the AMPK/mTOR/ULK1 pathway.