title: Multidrug Resistance-Associated Protein 3 Plays an Important Role in Protection against Acute Toxicity of Diclofenac.
abstract: Diclofenac (DCF) is a nonsteroidal anti-inflammatory drug commonly prescribed to reduce pain in acute and chronic inflammatory diseases. One of the main DCF metabolites is a reactive diclofenac acyl glucuronide (DCF-AG) that covalently binds to biologic targets and may contribute to adverse drug reactions arising from DCF use. Cellular efflux of DCF-AG is partially mediated by multidrug resistance-associated proteins (Mrp). The importance of Mrp2 during DCF-induced toxicity has been established, yet the role of Mrp3 remains largely unexplored. In the present work, Mrp3-null (KO) mice were used to study the toxicokinetics and toxicodynamics of DCF and its metabolites. DCF-AG plasma concentrations were 90% lower in KO mice than in wild-type (WT) mice, indicating that Mrp3 mediates DCF-AG basolateral efflux. In contrast, there were no differences in DCF-AG biliary excretion between WT and KO, suggesting that only DCF-AG basolateral efflux is compromised by Mrp3 deletion. Susceptibility to toxicity was also evaluated after a single high DCF dose. No signs of injury were detected in livers and kidneys; however, ulcers were found in the small intestines. Furthermore, the observed intestinal injuries were consistently more severe in KO compared with WT. DCF covalent adducts were observed in liver and small intestines; however, staining intensity did not correlate with the severity of injuries, implying that tissues respond differently to covalent modification. Overall, the data provide strong evidence that (1) in vivo Mrp3 plays an important role in DCF-AG disposition and (2) compromised Mrp3 function can enhance injury in the gastrointestinal tract after DCF treatment.
authors.affiliation: University of Connecticut, School of Pharmacy, Department of Pharmaceutical Sciences, Storrs, Connecticut (R.J.S., J.E.M.); University of Kansas Medical Center, Department of Internal Medicine, Kansas City, Kansas (I.L.C.); and Office of Translational Science, Rutgers University, Piscataway, New Jersey (M.J.G.).
authors.forename: Renato J
authors.initials: RJ
authors.lastname: Scialis
authors.affiliation: University of Connecticut, School of Pharmacy, Department of Pharmaceutical Sciences, Storrs, Connecticut (R.J.S., J.E.M.); University of Kansas Medical Center, Department of Internal Medicine, Kansas City, Kansas (I.L.C.); and Office of Translational Science, Rutgers University, Piscataway, New Jersey (M.J.G.).
authors.forename: Iván L
authors.initials: IL
authors.lastname: Csanaky
authors.affiliation: University of Connecticut, School of Pharmacy, Department of Pharmaceutical Sciences, Storrs, Connecticut (R.J.S., J.E.M.); University of Kansas Medical Center, Department of Internal Medicine, Kansas City, Kansas (I.L.C.); and Office of Translational Science, Rutgers University, Piscataway, New Jersey (M.J.G.).
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Goedken
authors.affiliation: University of Connecticut, School of Pharmacy, Department of Pharmaceutical Sciences, Storrs, Connecticut (R.J.S., J.E.M.); University of Kansas Medical Center, Department of Internal Medicine, Kansas City, Kansas (I.L.C.); and Office of Translational Science, Rutgers University, Piscataway, New Jersey (M.J.G.) jose.manautou@uconn.edu.
authors.forename: José E
authors.initials: JE
authors.lastname: Manautou
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000493:pharmacokinetics / Q000633:toxicity*; D001646:Bile / Q000378:metabolism; D004008:Diclofenac / Q000493:pharmacokinetics / Q000633:toxicity*; D020719:Glucuronides / Q000378:metabolism; D007150:Immunohistochemistry; D007410:Intestinal Diseases / Q000139:chemically induced / Q000235:genetics / Q000473:pathology; D007421:Intestine, Small / Q000378:metabolism / Q000473:pathology; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010437:Peptic Ulcer / Q000139:chemically induced / Q000473:pathology
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D000894:Anti-Inflammatory Agents, Non-Steroidal; D020719:Glucuronides; D004008:Diclofenac; C095122:multidrug resistance protein 3