Deletion of intestinal epithelial AMP-activated protein kinase alters distal colon permeability but not glucose homeostasis.
Deletion of intestinal epithelial AMP-activated protein kinase alters distal colon permeability but not glucose homeostasis.
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肠上皮AMP活化蛋白激酶的缺失改变远端结肠通透性，但不改变葡萄糖稳态。
DOI：
10.1016/j.molmet.2021.101183
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发表时间：
2021-05
影响因子：
8.1
通讯作者：
Viollet B
中科院分区：
文献类型：
--
作者：
Olivier S;Pochard C;Diounou H;Castillo V;Divoux J;Alcantara J;Leclerc J;Guilmeau S;Huet C;Charifi W;Varin TV;Daniel N;Foretz M;Neunlist M;Salomon BL;Ghosh P;Marette A;Rolli-Derkinderen M;Viollet B
肠上皮屏障（IEB）限制微生物和潜在有害物质从肠腔通过细胞旁空间，并且其完整性的破裂与各种胃肠道疾病和消化道外疾病相关。IEB渗透性增加与代谢稳态的破坏有关，导致肥胖和2型糖尿病。有趣的是，最近的研究发现了令人信服的证据表明，AMP激活的蛋白激酶（AMPK）信号通路在维持上皮细胞屏障功能中起着重要作用。然而，我们对肠道AMPK在调节IEB和葡萄糖稳态中的功能的了解仍然很少。我们产生了在肠上皮细胞中特异性缺失α1和α2 AMPK催化亚基的小鼠（IEC AMPK KO），并确定了高脂饮食（HFD）诱导的肥胖反应中AMPK的肠道特异性缺失的生理后果。我们结合组织学，功能和综合分析，以确定肠道AMPK损失对体内和体外肠通透性以及肥胖和代谢功能障碍的发展的影响。我们还通过粪便16 S rRNA测序测量IEB功能、葡萄糖稳态和肠道微生物群组成，确定了肠道AMPK缺失对诱导型小鼠模型（i-IEC AMPK KO）的影响。虽然在WT和IEC AMPK KO小鼠中体内肠渗透性没有差异，但在IEC AMPK KO小鼠的远端结肠中，在Ussing室中测量的离体跨细胞和细胞旁渗透性显著增加。这与pSer 425 GIV磷酸化的减少有关，pSer 425 GIV磷酸化是肠屏障渗漏的标志。然而，在肠上皮细胞中的紧密连接蛋白和固有层中的促炎细胞因子的表达在基因型之间没有差异。尽管HFD喂养的AMPK KO小鼠显示出应激极性信号传导途径的抑制和结肠通透性的伴随增加，但肠道AMPK的损失不会加剧体重增加或肥胖。AMPK的缺失也不足以改变对照饮食（CD）或HFD喂养小鼠的葡萄糖稳态或二甲双胍的急性降糖作用。CD喂养的i-IEC AMPK KO小鼠在稳态条件下在远端结肠中也表现出更高的渗透性，但令人惊讶的是，在HFD喂养时没有检测到这一点。i-IEC AMPK KO小鼠中上皮屏障功能的改变与肠道微生物群组成的变化相关，其中梭菌目和脱硫弧菌目水平较高。总之，我们的研究结果揭示了肠道AMPK在维持远端结肠IEB完整性方面的重要作用，但在调节葡萄糖稳态方面没有作用。我们的数据还强调了肠道微生物群与宿主AMPK之间的复杂相互作用。肠道AMPKα1和α2的缺失抑制了应激极性信号（SPS）通路。SPS途径的丧失与远端结肠中细胞旁通透性的增加相关。肠道AMPK对于二甲双胍的急性降糖作用是不可或缺的。肠道AMPK的丧失改变了肠道微生物群的组成。
The intestinal epithelial barrier (IEB) restricts the passage of microbes and potentially harmful substances from the lumen through the paracellular space, and rupture of its integrity is associated with a variety of gastrointestinal disorders and extra-digestive diseases. Increased IEB permeability has been linked to disruption of metabolic homeostasis leading to obesity and type 2 diabetes. Interestingly, recent studies have uncovered compelling evidence that the AMP-activated protein kinase (AMPK) signaling pathway plays an important role in maintaining epithelial cell barrier function. However, our understanding of the function of intestinal AMPK in regulating IEB and glucose homeostasis remains sparse. We generated mice lacking the two α1 and α2 AMPK catalytic subunits specifically in intestinal epithelial cells (IEC AMPK KO) and determined the physiological consequences of intestinal-specific deletion of AMPK in response to high-fat diet (HFD)-induced obesity. We combined histological, functional, and integrative analyses to ascertain the effects of gut AMPK loss on intestinal permeability in vivo and ex vivo and on the development of obesity and metabolic dysfunction. We also determined the impact of intestinal AMPK deletion in an inducible mouse model (i-IEC AMPK KO) by measuring IEB function, glucose homeostasis, and the composition of gut microbiota via fecal 16S rRNA sequencing. While there were no differences in in vivo intestinal permeability in WT and IEC AMPK KO mice, ex vivo transcellular and paracellular permeability measured in Ussing chambers was significantly increased in the distal colon of IEC AMPK KO mice. This was associated with a reduction in pSer425 GIV phosphorylation, a marker of leaky gut barrier. However, the expression of tight junction proteins in intestinal epithelial cells and pro-inflammatory cytokines in the lamina propria were not different between genotypes. Although the HFD-fed AMPK KO mice displayed suppression of the stress polarity signaling pathway and a concomitant increase in colon permeability, loss of intestinal AMPK did not exacerbate body weight gain or adiposity. Deletion of AMPK was also not sufficient to alter glucose homeostasis or the acute glucose-lowering action of metformin in control diet (CD)- or HFD-fed mice. CD-fed i-IEC AMPK KO mice also presented higher permeability in the distal colon under homeostatic conditions but, surprisingly, this was not detected upon HFD feeding. Alteration in epithelial barrier function in the i-IEC AMPK KO mice was associated with a shift in the gut microbiota composition with higher levels of Clostridiales and Desulfovibrionales. Altogether, our results revealed a significant role of intestinal AMPK in maintaining IEB integrity in the distal colon but not in regulating glucose homeostasis. Our data also highlight the complex interaction between gut microbiota and host AMPK. Deletion of intestinal AMPKα1 and α2 suppresses the stress-polarity signaling (SPS) pathway. Loss of the SPS pathway is associated with increased paracellular permeability in the distal colon. Intestinal AMPK is dispensable for the acute glucose-lowering action of metformin. Loss of intestinal AMPK alters the gut microbiota composition.
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影响因子：
7.7
作者：
Cani, Patrice D.;Amar, Jacques;Burcelin, Remy
通讯作者：
Burcelin, Remy
影响因子：
3.7
作者：
Chassaing B;Srinivasan G;Delgado MA;Young AN;Gewirtz AT;Vijay-Kumar M
通讯作者：
Vijay-Kumar M
影响因子：
29
作者：
Donohoe DR;Garge N;Zhang X;Sun W;O'Connell TM;Bunger MK;Bultman SJ
通讯作者：
Bultman SJ
影响因子：
48
作者：
Callahan BJ;McMurdie PJ;Rosen MJ;Han AW;Johnson AJ;Holmes SP
通讯作者：
Holmes SP
影响因子：
24.5
作者：
Anhe, Fernando F.;Nachbar, Renato T.;Marette, Andre
通讯作者：
Marette, Andre