Butyrate reduces adherent-invasive E. coli-evoked disruption of epithelial mitochondrial morphology and barrier function: involvement of free fatty acid receptor 3
Samira A. Hamed,
Armaan Mohan,
Saranya Navaneetha Krishnan,
Arthur Wang,
Marija Drikic,
Nicole L. Prince,
Ian A. Lewis,
Jane Shearer,
Åsa V. Keita,
Johan D. Söderholm,
Timothy E. Shutt,
Derek M. McKay
Affiliations
Samira A. Hamed
Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
Armaan Mohan
Departments of Medical Genetics and Biochemistry & Molecular Biology, Alberta Children’s Hospital Research Institute, Hotchkiss Brain Institute, Snyder Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
Saranya Navaneetha Krishnan
Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
Arthur Wang
Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
Marija Drikic
Calgary Metabolomics Research Facility, Department of Biological Sciences, Faculty of Science, University of Calgary, Calgary, Canada
Nicole L. Prince
Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
Ian A. Lewis
Calgary Metabolomics Research Facility, Department of Biological Sciences, Faculty of Science, University of Calgary, Calgary, Canada
Jane Shearer
Department of Biochemistry and Molecular Biology, Faculty of Kinesiology, University of Calgary, Calgary, Canada
Åsa V. Keita
Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology, Linköping University, Linköping, Sweden
Johan D. Söderholm
Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology, Linköping University, Linköping, Sweden
Timothy E. Shutt
Departments of Medical Genetics and Biochemistry & Molecular Biology, Alberta Children’s Hospital Research Institute, Hotchkiss Brain Institute, Snyder Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
Derek M. McKay
Gastrointestinal Research Group, Inflammation Research Network, Host-Parasite Interactions Program, Department of Physiology & Pharmacology, Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
ABSTRACTGut bacteria provide benefits to the host and have been implicated in inflammatory bowel disease (IBD), where adherent-invasive E. coli (AIEC) pathobionts (e.g., strain LF82) are associated with Crohn’s disease. E. coli-LF82 causes fragmentation of the epithelial mitochondrial network, leading to increased epithelial permeability. We hypothesized that butyrate would limit the epithelial mitochondrial disruption caused by E. coli-LF82. Human colonic organoids and the T84 epithelial cell line infected with E. coli-LF82 (MOI = 100, 4 h) showed a significant increase in mitochondrial network fission that was reduced by butyrate (10 mM) co-treatment. Butyrate reduced the loss of mitochondrial membrane potential caused by E. coli-LF82 and increased expression of PGC-1[Formula: see text] mRNA, the master regulator of mitochondrial biogenesis. Metabolomics revealed that butyrate significantly altered E. coli-LF82 central carbon metabolism leading to diminished glucose uptake and increased succinate secretion. Correlating with preservation of mitochondrial network form/function, butyrate reduced E. coli-LF82 transcytosis across T84-cell monolayers. The use of the G-protein inhibitor, pertussis toxin, implicated GPCR signaling as critical to the effect of butyrate, and the free fatty acid receptor three (FFAR3, GPR41) agonist, AR420626, reproduced butyrate’s effect in terms of ameliorating the loss of barrier function and reducing the mitochondrial fragmentation observed in E. coli-LF82 infected T84-cells and organoids. These data indicate that butyrate helps maintain epithelial mitochondrial form/function when challenged by E. coli-LF82 and that this occurs, at least in part, via FFAR3. Thus, loss of butyrate-producing bacteria in IBD in the context of pathobionts would contribute to loss of epithelial mitochondrial and barrier functions that could evoke disease and/or exaggerate a low-grade inflammation.
