ESRRA (estrogen related receptor alpha) is a critical regulator of intestinal homeostasis through activation of autophagic flux via gut microbiota.

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.