title: Peroxynitrite mediates muscle insulin resistance in mice via nitration of IRbeta/IRS-1 and Akt.
abstract: Accumulating evidence suggests that peroxynitrite (ONOO(-)) is involved in the pathogenesis of insulin resistance. In the current study, we investigated whether insulin resistance in vivo could be mediated by nitration of proteins involved in the early steps of the insulin signal transduction pathway. Exogenous peroxynitrite donated by 3-morpholinosydnonimine hydrochloride (SIN-1) induced in vivo nitration of the insulin receptor beta subunit (IRbeta), insulin receptor substrate (IRS)-1, and protein kinase B/Akt (Akt) in skeletal muscle of mice and dramatically reduced whole-body insulin sensitivity and muscle insulin signaling. Moreover, in high-fat diet (HFD)-fed insulin-resistant mice, we observed enhanced nitration of IRbeta and IRS-1 in skeletal muscle, in parallel with impaired whole-body insulin sensitivity and muscle insulin signaling. Reversal of nitration of these proteins by treatment with the peroxynitrite decomposition catalyst FeTPPS yielded an improvement in whole-body insulin sensitivity and muscle insulin signaling in HFD-fed mice. Taken together, these findings provide new mechanistic insights for the involvement of peroxynitrite in the development of insulin resistance and suggest that nitration of proteins involved in the early steps of insulin signal transduction is a novel molecular mechanism of HFD-induced muscle insulin resistance.
authors.affiliation: Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.forename: Kaixun
authors.initials: K
authors.lastname: Huang
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage; D015971:Gene Expression Regulation, Enzymologic; D007328:Insulin / Q000378:metabolism*; D055504:Insulin Receptor Substrate Proteins / Q000378:metabolism; D007333:Insulin Resistance; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008981:Molsidomine / Q000031:analogs & derivatives / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D030421:Peroxynitrous Acid / Q000378:metabolism* / Q000494:pharmacology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011972:Receptor, Insulin / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D004041:Dietary Fats; D007328:Insulin; D055504:Insulin Receptor Substrate Proteins; C526295:Irs1 protein, mouse; D030421:Peroxynitrous Acid; C002385:linsidomine; D008981:Molsidomine; D052247:Nitric Oxide Synthase Type II; D011972:Receptor, Insulin; D051057:Proto-Oncogene Proteins c-akt