ABSTRACT

The orphan nuclear receptor ESRRA (estrogen related receptor alpha) is critical in mitochondrial biogenesis and macroautophagy/autophagy function; however, the roles of ESRRA in intestinal function remain uncharacterized. Herein we identified that ESRRA acts as a key regulator of intestinal homeostasis by amelioration of colonic inflammation through activation of autophagic flux and control of host gut microbiota. Esrra-deficient mice presented with increased susceptibility to dextran sodium sulfate (DSS)-induced colitis with upregulation of intestinal inflammation. In addition, esrra-null mice had depressed AMP-activated protein kinase phosphorylation (AMPK), lower levels of TFEB (transcription factor EB), and accumulation of SQSTM1/p62 (sequestosome 1) with defective mitochondria in intestinal tissues. Esrra-deficient mice showed distinct gut microbiota composition and significantly higher microbial diversity than wild-type (WT) mice. Cohousing or fecal microbiota transplantation from WT mice to Esrra-deficient mice ameliorated DSS-induced colitis severity. Importantly, patients with ulcerative colitis (UC) had significantly decreased ESRRA expression in intestinal mucosal tissues that correlated with disease activity, suggesting clinical relevance of ESRRA in UC. Taken together, our results show that ESRRA contributes to intestinal homeostasis through autophagy activation and gut microbiota control to protect the host from detrimental inflammation and dysfunctional mitochondria.

Abbreviations: ABX, antibotics; AMPK, AMP-activated protein kinase; ATP5A1, ATP synthase, H+ transporting, mitochondrial F1 complex, alpha subunit 1; BECN1, beclin1, autophagy related, CCL, C-C motif chemokine ligand; CD, Crohn disease; CLDN, claudin; COX4I1, cytochrome c oxidase subunit 4I1; cKO, conditional knockout; cWT, conditional wild-type; CXCL, C-X-C motif chemokine ligand; DAI, disease activity index; DSS, dextran sodium sulfate; EGFP, enhanced green fluorescent protein; ESRR, estrogen related receptor; ESRRA, estrogen related receptor alpha; Esrra+/+, Esrra wild type; esrra–/-, esrra homozygous knockout; FMT, fecal microbiota transplantation; GABARAP, gamma-aminobutyric acid receptor associated protein; GSEA, gene set enrichment analysis; IBD, inflammatory bowel disease; IL, interleukin; KO, knockout; LAMP1, lysosomal-associated membrane protein 1; LCN2, lipocalin 2; LEfSe, linear discriminant analysis (LDA) effect size; LPS, lipopolysachharide; MAP1LC3/LC3, microtubule associated protein 1 light chain 3; NDUFAB1, NADH: ubiquinone oxidoreductase subunit AB1; OCLN, occludin; OUT, operational taxonomic unit; OXPHOS, oxidative phosphorylation; PCoA, principal coordinate analysis; PPARGC1A, PPARG coactiva- tor 1 alpha; PRKAA, 5’-AMP-activated protein kinase catalytic subunit alpha; PTGS2/COX2, prostaglandin-endoperoxide synthase 2; RAB7, member RAS oncogene family; SDHB, succinate dehydrogenase complex, subunit B, iron sulfur (Ip); SQSTM1/p62, sequestosome 1; S100A9, S100 calcium binding protein A9 (calgranulin B); TCA, tricarboxylic acid; TFEB, transcription factor EB; TNF, tumor necrosis factor; UC, ulcerative colitis; UCP2, uncoupling protein 2 (mitochondrial, proton carrier); UQCRC1, ubiquinol-cytochrome c reductase core protein 1; UVRAG, UV radiation resistance associated gene; Vil1, villin; VPS11, VPS11, CORVET/HOPS core sub-unit; WT, wild type.

摘要

孤儿核受体 ESRRA（雌激素相关受体 α）在线粒体生物发生和巨自噬/自噬功能中至关重要；然而，ESRRA 在肠道功能中的作用仍未明确。在这里，我们发现 ESRRA 通过激活自噬通量和控制宿主肠道微生物群来改善结肠炎症，从而充当肠道稳态的关键调节剂。Esrra 缺陷小鼠对葡聚糖硫酸钠 (DSS) 诱导的结肠炎的易感性增加，并伴有肠道炎症的上调。此外，esrra-null 小鼠的 AMP 活化蛋白激酶磷酸化 (AMPK) 降低，TFEB (转录因子 EB) 水平降低，SQSTM1/p62 (sequestosome 1) 积累，肠组织中有缺陷的线粒体。与野生型 (WT) 小鼠相比，Esrra 缺陷小鼠表现出明显的肠道微生物群组成和显着更高的微生物多样性。从 WT 小鼠到Esrra 缺陷小鼠的同居或粪便微生物群移植改善了 DSS 诱导的结肠炎严重程度。重要的是，溃疡性结肠炎 (UC) 患者的ESRRA显着降低与疾病活动相关的肠黏膜组织中的表达，表明 ESRRA 在 UC 中的临床相关性。总之，我们的研究结果表明，ESRRA 通过自噬激活和肠道微生物群控制来促进肠道稳态，以保护宿主免受有害炎症和线粒体功能障碍。

缩写：ABX，抗生素；AMPK，AMP 活化蛋白激酶；ATP5A1、ATP 合酶、H+ 转运、线粒体 F1 复合物、α 亚基 1；BECN1、beclin1、自噬相关、CCL、CC基序趋化因子配体；CD，克罗恩病；CLDN，克劳丁；COX4I1，细胞色素 c 氧化酶亚基 4I1；cKO，有条件淘汰赛；cWT，条件野生型；CXCL，CXC基序趋化因子配体；DAI，疾病活动指数；DSS，葡聚糖硫酸钠；EGFP，增强型绿色荧光蛋白；ESRR，雌激素相关受体；ESRRA，雌激素相关受体α；Esrra+/+，Esrra 野生型；esrra–/-，esrra 纯合子敲除；FMT，粪便微生物群移植；GABARAP，γ-氨基丁酸受体相关蛋白；GSEA，基因集富集分析；IBD，炎症性肠病；IL，白细胞介素；KO，淘汰赛；LAMP1，溶酶体相关膜蛋白 1；LCN2，脂质运载蛋白 2；LEfSe，线性判别分析（LDA）效应大小；LPS，脂多糖；MAP1LC3/LC3，微管相关蛋白 1 轻链 3；NDUFAB1，NADH：泛醌氧化还原酶亚基 AB1；OCLN，闭塞蛋白；OUT，操作分类单元；OXPHOS，氧化磷酸化；PCoA，主坐标分析；PPARGC1A，PPARG 共激活剂 1 α；PRKAA，5'-AMP 活化蛋白激酶催化亚基 α；PTGS2/COX2，前列腺素内过氧化物合酶 2；RAB7，RAS癌基因家族成员；SDHB，琥珀酸脱氢酶复合物，亚基 B，铁硫 (Ip)；SQSTM1/p62，隔离体 1；S100A9、S100 钙结合蛋白 A9（钙颗粒蛋白 B）；TCA，三羧酸；TFEB，转录因子 EB；TNF，肿瘤坏死因子；UC，溃疡性结肠炎；UCP2，解偶联蛋白 2（线粒体，质子载体）；UQCRC1, 泛醇-细胞色素 c 还原酶核心蛋白 1；UVRAG，抗紫外线辐射相关基因；Vil1，小人；VPS11、VPS11、CORVET/HOPS核心子单元；WT，野生型。