title: The role of adipose tissue-associated macrophages and T lymphocytes in the pathogenesis of inflammatory bowel disease.
abstract: Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders of the gastrointestinal tract that affect more than 3 million people worldwide, but the pathological etiology is still unknown. The overall purpose of our investigations was to elucidate the possibility of pathological causes of IBD, and therefore, we determined the difference of inflammatory cytokine profiles in adipose tissue macrophages (ATMs) and T lymphocytes (ATTs) obtained near active lesions of IBD; investigated whether the alteration in ATM activation induces genes involved in collagen formation; and evaluated the effects of fatty acid oxidation inhibitors on factors involved in inflammation and collagen production by ATMs in IBD. Adipose tissues (ATs) were collected near active lesions and also at the margin of resected segments of the bowel from IBD patients with ulcerative colitis (UC) and CD (n=14/group). Normal appearing ATs from control subjects (n=14) who had colon resection for adenocarcinoma were collected as far away from the cancer lesion as possible to rule out possible changes. Compared with inactive disease lesions, ATMs and ATTs from active lesions released more IL-6, IL-4 and IL-13. Treatments of cytokine IL-4 and/or IL-13 to ATMs reduced iNOS expression but increased Arg-I expression which were exacerbated when treated with T cell- and adipocyte-conditioned medium. However, fatty acid oxidation inhibitors prevented the effects of cytokines IL-4 and/or IL-13 on iNOS and Arg-I expressions. This study was the first to show the effect of IL-4 and IL-13 on collagen formation, through iNOS and Arg-I expressions, that was exacerbated in a condition that mimics in vivo condition of active lesions. Moreover, our study was the first to provide potential benefits of fatty acid oxidation inhibitors to ATMs on preventing collagen formation; thus, providing therapeutic implications for individuals with intestinal fibrosis and stricture lesions, although future study should be guaranteed to elucidate the underlying mechanisms.
authors.affiliation: Department of Pharmacology, Physiology & Neuroscience, School of Medicine, University of South Carolina, Columbia, SC 29208, USA.
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Jung
authors.forename: Arpit
authors.initials: A
authors.lastname: Saxena
authors.forename: Kamaljeet
authors.initials: K
authors.lastname: Kaur
authors.forename: Emma
authors.initials: E
authors.lastname: Fletcher
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Ponemone
authors.forename: James M
authors.initials: JM
authors.lastname: Nottingham
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Sheppe
authors.forename: Maria
authors.initials: M
authors.lastname: Petroni
authors.forename: Jennifer
authors.initials: J
authors.lastname: Greene
authors.forename: Kelly
authors.initials: K
authors.lastname: Graves
authors.forename: Manjeshwar Shrinath
authors.initials: MS
authors.lastname: Baliga
authors.forename: Raja
authors.initials: R
authors.lastname: Fayad
mesh_terms: D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D000273:Adipose Tissue / Q000187:drug effects / Q000473:pathology*; D000328:Adult; D001119:Arginase / Q000378:metabolism; D016022:Case-Control Studies; D017077:Culture Media, Conditioned / Q000494:pharmacology; D016207:Cytokines / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000209:etiology* / Q000276:immunology / Q000473:pathology* / Q000601:surgery; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D009578:Nitrobenzenes / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D013864:Thioglycolates / Q000494:pharmacology; D055815:Young Adult
chemical_list: D017077:Culture Media, Conditioned; D016207:Cytokines; D009578:Nitrobenzenes; D013449:Sulfonamides; D013864:Thioglycolates; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; C017487:2-mercaptoacetate; D052247:Nitric Oxide Synthase Type II; D001119:Arginase; D015232:Dinoprostone