CaMKIα regulates AMP kinase-dependent, TORC-1-independent autophagy during lipopolysaccharide-induced acute lung neutrophilic inflammation.
CaMKIα regulates AMP kinase-dependent, TORC-1-independent autophagy during lipopolysaccharide-induced acute lung neutrophilic inflammation.
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DOI：
10.4049/jimmunol.1102975
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发表时间：
2013-04-01
期刊：
影响因子：
--
通讯作者：
Rosengart MR
中科院分区：
文献类型：
--
作者：
Guo L;Stripay JL;Zhang X;Collage RD;Hulver M;Carchman EH;Howell GM;Zuckerbraun BS;Lee JS;Rosengart MR
自噬是一种进化上保守的细胞质过程，由能量变阻器mTOR和AMPK调节，其回收受损或未使用的蛋白质和细胞器。它已被描述为免疫细胞的重要效应臂。我们已经证明，细胞质定向的钙/钙调素依赖性蛋白激酶I α（CaMKIα）调节巨噬细胞（Mφ）的炎症表型。在此，我们假设CaMKIα介导Mφ自噬。LPS诱导RAW 264.7细胞和小鼠腹膜Mφ中的自噬，其被生化CaMK抑制或CaMKIα siRNA减弱。抑制CaMKIα可降低LPS诱导的p-Thr 172 AMPK和TORC 1活性，组成型活性CaMKIα的表达可诱导p-Thr 172 AMPK和自噬，而激酶缺陷型突变体则不会诱导自噬，AMPK抑制剂化合物C可减弱自噬。免疫共沉淀和体外激酶试验表明，CaMKIα激活AMPK，从而诱导ATG 7，后者也定位于该CaMKIα-AMPK复合物。在LPS诱导的肺部炎症期间，接受CaMKIαsiRNA的C57 Bl/6小鼠显示肺和支气管肺泡免疫细胞自噬减少，这与中性粒细胞募集减少、髓过氧化物酶活性和空气空间细胞因子浓度降低相关。使用靶向PI 3激酶VPS 34的siRNA独立抑制自噬，在肺自噬和中性粒细胞募集方面产生类似的减少。因此，一种新的CaMKIα-AMPK通路在暴露于LPS的Mφ中被迅速激活，并调节早期自噬反应，而不依赖于TORC 1抑制。这些机制似乎在体内协调LPS诱导的肺中性粒细胞募集和炎症中起作用。
Autophagy is an evolutionarily conserved cytoplasmic process regulated by the energy rheostats mTOR and AMPK that recycles damaged or unused proteins and organelles. It has been described as an important effector arm of immune cells. We have shown that the cytoplasmically oriented calcium/calmodulin-dependent protein kinase I α (CaMKIα) regulates the inflammatory phenotype of the macrophage (Mφ). Here, we hypothesize that CaMKIα mediates Mφ autophagy. LPS induced autophagy in RAW 264.7 cells and murine peritoneal Mφ that was attenuated with biochemical CaMK inhibition or CaMKIα siRNA. Inhibition of CaMKIα reduced LPS-induced p-Thr172AMPK and TORC1 activity, and expression of a constitutively active CaMKIα but not a kinase-deficient mutant induced p-Thr172AMPK and autophagy that was attenuated by the AMPK inhibitor Compound C. Co-immunoprecipitation and in vitro kinase assays demonstrated that CaMKIα activates AMPK, thereby inducing ATG7, which also localizes to this CaMKIα-AMPK complex. During LPS-induced lung inflammation, C57Bl/6 mice receiving CaMKIαsiRNA displayed reduced lung and bronchoalveolar immune cell autophagy that correlated with reduced neutrophil recruitment, myeloperoxidase activity, and air space cytokine concentration. Independently inhibiting autophagy, using siRNA targeting the PI3 kinase VPS34, yielded similar reductions in lung autophagy and neutrophil recruitment. Thus, a novel CaMKIα-AMPK pathway is rapidly activated in Mφ exposed to LPS and regulates an early autophagic response, independent of TORC1 inhibition. These mechanisms appear to be operant in vivo in orchestrating LPS-induced lung neutrophil recruitment and inflammation.
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DOI：
10.1042/bj20091372
发表时间：
2010-01-27
期刊：
The Biochemical journal
影响因子：
--
作者：
Fogarty S;Hawley SA;Green KA;Saner N;Mustard KJ;Hardie DG
通讯作者：
Hardie DG
影响因子：
11.1
作者：
He C;Klionsky DJ
通讯作者：
Klionsky DJ
影响因子：
21.3
作者：
通讯作者：
--
影响因子：
4.8
作者：
Chatila, T;Anderson, KA;Means, AR
通讯作者：
Means, AR
影响因子：
7.5
作者：
Nobukuni, Takahiro;Kozma, Sara C.;Thomas, George
通讯作者：
Thomas, George