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Styskal J, Nwagwu FA, Watkins YN, Liang H, Richardson A, Musi N, Salmon AB. Methionine sulfoxide reductase A affects insulin resistance by protecting insulin receptor function. Free Radic Biol Med 2013; 56:123-32. [PMID: 23089224 PMCID: PMC3578155 DOI: 10.1016/j.freeradbiomed.2012.10.544] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 10/07/2012] [Accepted: 10/15/2012] [Indexed: 02/06/2023]
Abstract
Oxidative stress plays a significant role in the development of insulin resistance; however, the cellular targets of oxidation that cause insulin resistance have yet to be fully elucidated. Methionine sulfoxide reductases reduce oxidized methionine residues, thereby repairing and protecting proteins from oxidation. Recently, several genome-wide analyses have found human obesity to be strongly correlated with polymorphisms near the methionine sulfoxide reductase A (MsrA) locus. In this study, we tested whether modulation of MsrA expression significantly alters the development of obesity and/or insulin resistance in mice. We show that mice lacking MsrA (MsrA(-/-)) are prone to the development of high-fat-diet-induced insulin resistance and a reduced physiological insulin response compared to high-fat-fed wild-type mice. We also show that oxidative stress in C2C12 cell cultures reduces both insulin-stimulated phosphorylation and autophosphorylation of the insulin receptor. Tissues from high-fat-fed mice show similar reduction in insulin receptor function and increase in insulin receptor oxidation, which are further exacerbated by the lack of MsrA. Together, these data demonstrate for the first time that MsrA and protein oxidation play a role in the regulation of glucose homeostasis. In addition, these data support a novel hypothesis that obesity-induced insulin resistance is caused in part by reduced function of insulin signaling proteins arising from protein oxidation.
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Affiliation(s)
- JennaLynn Styskal
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Cellular & Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Florence A. Nwagwu
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Yvonne N. Watkins
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Hanyu Liang
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Division of Diabetes, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
| | - Arlan Richardson
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Cellular & Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, 78229
| | - Nicolas Musi
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Division of Diabetes, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, 78229
| | - Adam B. Salmon
- The Sam and Ann Barshop Institute for Longevity and Aging Studies, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78229
- The Geriatric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, Texas, 78229
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