Salidroside attenuates hypoxia-induced pulmonary arterial smooth muscle cell proliferation and apoptosis resistance by upregulating autophagy through the AMPK-mTOR-ULK1 pathway.
Salidroside attenuates hypoxia-induced pulmonary arterial smooth muscle cell proliferation and apoptosis resistance by upregulating autophagy through the AMPK-mTOR-ULK1 pathway.
复制标题
红景天苷通过 AMPK-mTOR-ULK1 途径上调自噬，从而减弱缺氧诱导的肺动脉平滑肌细胞增殖和凋亡抵抗。
DOI：
10.1186/s12890-017-0477-4
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发表时间：
2017-12-12
影响因子：
3.1
通讯作者：
Huang X
中科院分区：
文献类型：
--
作者：
Gui D;Cui Z;Zhang L;Yu C;Yao D;Xu M;Chen M;Wu P;Li G;Wang L;Huang X
最近的研究表明，腺苷一磷酸激活的蛋白激酶（AMPK）和雷帕霉素的哺乳动物靶蛋白（mTOR）都是能量传感器，与自噬有关。我们最近的报告表明，红景天苷可以通过AMPK途径对缺氧诱导的肺动脉平滑肌细胞（PASMC）增殖和抗凋亡发挥保护作用。本研究旨在探讨缺氧条件下PASMCs中AMPK、mTOR和ULK 1之间的关系，并探讨红景天苷的保护作用是否与自噬细胞死亡途径有关。培养大鼠PASMCs，分为常氧组、低氧组、低氧+mTOR激动剂MHY 1485组、低氧+mTOR抑制剂雷帕霉素组和低氧+红景天苷组。将低分化细胞按所示处理24小时。通过CCK-8测定评价细胞活力。TUNEL法检测细胞凋亡。采用串联mRFP-GFP荧光显微镜观察PASMCs的自噬通量。电镜下观察自噬体。Western blot检测LC 3、p62、AMPK、P-AMPK（Thr 172）、P-ULK 1（Ser 555和Ser 317）、mTOR、P-mTOR（Ser 2448）、ULK 1和P-ULK 1（Ser 757）蛋白表达。低氧条件下PASMC增殖和凋亡抵抗。与常氧组相比，低氧组自噬流量、自噬体数量和LC 3 II/LC 3 I比值增加，而p62表达降低。雷帕霉素或红景天苷治疗逆转缺氧诱导的PASMC增殖和凋亡抵抗，并进一步增加自噬流量，自噬体水平和LC 3 II/LC 3 I比值，但降低p62表达。用MHY 1485处理逆转缺氧诱导的PASMC凋亡抗性，降低自噬通量，以及增加自噬体水平、LC 3 II/LC 3 I比率和p62表达。AMPK-ULK 1通路中的P-AMPK（Thr 172）和P-ULK 1（Ser 555）在缺氧组中增加，并且在红景天苷组中进一步增加。雷帕霉素和MHY 1485对P-AMPK（Thr 172）或P-ULK 1（Ser 555）均无影响。ULK 1在丝氨酸317处的磷酸化对五组没有显著影响。此外，AMPK-mTOR-ULK 1通路的P-mTOR（Ser 2448）和P-ULK 1（Ser 757）在缺氧组中降低，并且在红景天苷组中进一步降低。MHY 1485增加P-mTOR（Ser 2448）和P-ULK 1（Ser 757）的表达，而雷帕霉素具有相反的作用。红景天苷可能通过AMPKα1-ULK 1和AMPKα1-mTOR-ULK 1途径上调自噬，抑制缺氧诱导的PASMC增殖，逆转其凋亡抵抗。
Recent studies have shown that both adenosine monophosphate activated protein kinase (AMPK) and the mammalian target of rapamycin (mTOR) are energy sensors and are related to autophagy. Our recent reports have shown that salidroside can exert protective effects against hypoxia-induced pulmonary arterial smooth muscle cell (PASMC) proliferation and apoptosis resistance through the AMPK pathway. This study aims to explore the relationship among AMPK, mTOR and ULK1 in PASMCs under hypoxic conditions and to investigate whether the protective effects of salidroside are related to the autophagic cell death pathway. Rat PASMCs were cultured and divided into five groups: the normoxia, hypoxia, hypoxia + MHY1485 (mTOR agonist), hypoxia + rapamycin (mTOR inhibitor) and hypoxia + salidroside groups. Hypoxic cells were treated as indicated for 24 h. Cell viability was evaluated by the CCK-8 assay. Cell apoptosis was measured by the TUNEL assay. The autophagy flux of PASMCs was evaluated with tandem mRFP-GFP fluorescence microscopy. Autophagosomes were detected by electron microscopy. Protein expression of LC3, p62, AMPK, P-AMPK (Thr 172), P-ULK1 (Ser 555 and Ser 317), mTOR, P-mTOR (Ser 2448), ULK1 and P-ULK1 (Ser 757) was detected by western blot assay. PASMC proliferation and apoptosis resistance were observed under hypoxic conditions. Autophagy flux, the number of autophagosomes and the LC3II/LC3I ratio were increased in the hypoxia group compared with the normoxia group, whereas p62 expression was decreased. Treatment with rapamycin or salidroside reversed hypoxia-induced PASMC proliferation and apoptosis resistance and further increased autophagy flux, autophagosome levels and the LC3II/LC3I ratio but decreased p62 expression. Treatment with MHY1485 reversed hypoxia-induced PASMC apoptosis resistance and decreased autophagy flux as well as increased autophagosome levels, the LC3II/LC3I ratio and p62 expression. P-AMPK (Thr 172) and P-ULK1 (Ser 555) of the AMPK-ULK1 pathway were increased in the hypoxia group and were further increased in the salidroside group. Rapamycin and MHY1485 had no effect on either P-AMPK (Thr 172) or P-ULK1 (Ser 555). Phosphorylation of ULK1 at serine 317 did not significantly affect the five groups. Furthermore, P-mTOR (Ser 2448) and P-ULK1 (Ser 757) of the AMPK-mTOR-ULK1 pathway were decreased in the hypoxia group and were further decreased in the salidroside group. MHY1485 increased the expression of both P-mTOR(Ser 2448) and P-ULK1(Ser 757), whereas rapamycin had the opposite effect. Salidroside might inhibit hypoxia-induced PASMC proliferation and reverse apoptosis resistance via the upregulation of autophagy through both the AMPKα1-ULK1 and AMPKα1-mTOR-ULK1 pathways.
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影响因子：
11.1
作者：
He C;Klionsky DJ
通讯作者：
Klionsky DJ
AMP激活的蛋白激酶对ULK1（HATG1）的磷酸化将能量传感连接到线粒体。
DOI：
10.1126/science.1196371
发表时间：
2011-01-28
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Egan DF;Shackelford DB;Mihaylova MM;Gelino S;Kohnz RA;Mair W;Vasquez DS;Joshi A;Gwinn DM;Taylor R;Asara JM;Fitzpatrick J;Dillin A;Viollet B;Kundu M;Hansen M;Shaw RJ
通讯作者：
Shaw RJ
MTORC1激活减少了衰老和特发性肺纤维化的自噬，并有助于IPF成纤维细胞的凋亡抗性。
影响因子：
7.8
作者：
Romero Y;Bueno M;Ramirez R;Álvarez D;Sembrat JC;Goncharova EA;Rojas M;Selman M;Mora AL;Pardo A
通讯作者：
Pardo A
影响因子：
21.3
作者：
通讯作者：
--
影响因子：
15.9
作者：
Ruderman, Neil B.;Carling, David;Cacicedo, Jose M.
通讯作者：
Cacicedo, Jose M.