title: Multidrug resistance-associated transporter 2 regulates mucosal inflammation by facilitating the synthesis of hepoxilin A3.
abstract: Neutrophil transmigration across mucosal surfaces contributes to dysfunction of epithelial barrier properties, a characteristic underlying many mucosal inflammatory diseases. Thus, insight into the directional movement of neutrophils across epithelial barriers will provide important information relating to the mechanisms of such inflammatory disorders. The eicosanoid hepoxilin A(3), an endogenous product of 12-lipoxygenase activity, is secreted from the apical surface of the epithelial barrier and establishes a chemotactic gradient to guide neutrophils from the submucosa across epithelia to the luminal site of an inflammatory stimulus, the final step in neutrophil recruitment. Currently, little is known regarding how hepoxilin A(3) is secreted from the intestinal epithelium during an inflammatory insult. In this study, we reveal that hepoxilin A(3) is a substrate for the apical efflux ATP-binding protein transporter multidrug resistance-associated protein 2 (MRP2). Moreover, using multiple in vitro and in vivo models, we show that induction of intestinal inflammation profoundly up-regulates apical expression of MRP2, and that interfering with hepoxilin A(3) synthesis and/or inhibition of MRP2 function results in a marked reduction in inflammation and severity of disease. Lastly, examination of inflamed intestinal epithelia in human biopsies revealed up-regulation of MRP2. Thus, blocking hepoxilin A(3) synthesis and/or inhibiting MRP2 may lead to the development of new therapeutic strategies for the treatment of epithelial-associated inflammatory conditions.
authors.affiliation: Department of Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital, Boston, MA 02129, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Pazos
authors.forename: Dario
authors.initials: D
authors.lastname: Siccardi
authors.forename: Karen L
authors.initials: KL
authors.lastname: Mumy
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Bien
authors.forename: Steve
authors.initials: S
authors.lastname: Louie
authors.forename: Hai Ning
authors.initials: HN
authors.lastname: Shi
authors.forename: Karsten
authors.initials: K
authors.lastname: Gronert
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Mrsny
authors.forename: Beth A
authors.initials: BA
authors.lastname: McCormick
mesh_terms: D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives* / Q000276:immunology / Q000378:metabolism; D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000276:immunology / Q000378:metabolism; D005786:Gene Expression Regulation / Q000276:immunology; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D007410:Intestinal Diseases / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D007413:Intestinal Mucosa / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000096:biosynthesis / Q000276:immunology*; D020556:Neutrophil Infiltration / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
chemical_list: D015126:8,11,14-Eicosatrienoic Acid; D001092:Arachidonate 12-Lipoxygenase; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C000715087:ABCC2 protein, human; C038243:8-hydroxy-11,12-epoxyeicosa-5,9,14-trienoic acid