Prolonged Incubation in PUGNAc Results in Increased Protein O-Linked Glycosylation and Insulin Resistance in Rat Skeletal Muscle

• Edward B. Arias

  From the Department of Kinesiology, University of Wisconsin-Madison, Madison, Wisconsin

• Junghoon Kim

  From the Department of Kinesiology, University of Wisconsin-Madison, Madison, Wisconsin

• Gregory D. Cartee

  From the Department of Kinesiology, University of Wisconsin-Madison, Madison, Wisconsin

抄録

Increased flux through the hexosamine biosynthetic pathway and increased O-linked glycosylation (N-acetylglucosamine [O-GlcNAc]) of proteins have been implicated in insulin resistance. Previous research in 3T3-L1 adipocytes indicated that insulin-stimulated glucose uptake and phosphorylation of Akt were reduced after incubation with O-(2-acetamido-2-deoxy-d-glucopyranosylidene)amino-N-phenylcarbamate (PUGNAc; 100 μmol/l), an inhibitor of the O-GlcNAcase that catalyzes removal of O-GlcNAc from proteins. Therefore, in this study, we tested the effects of PUGNAc on skeletal muscle. Incubation of rat epitrochlearis muscles for 19 h with 100 μmol/l PUGNAc resulted in a marked increase in O-GlcNAcylation of multiple proteins. Incubation with PUGNAc reduced glucose transport with a physiologic insulin concentration without affecting glucose transport without insulin or with supraphysiologic insulin. PUGNAc did not significantly alter insulin-stimulated phosphorylation of Akt (serine and threonine) or its substrates glycogen synthase kinase (GSK)3α and GSK3β. Insulin stimulated a dose-dependent (12.0 > 0.6 > 0 nmol/l) increase in the phosphorylation of a 160-kDa protein detected using an antibody against an Akt substrate phosphomotif. PUGNAc treatment did not alter phosphorylation of this protein. These results indicate that PUGNAc is an effective inhibitor of O-GlcNAcase in skeletal muscle and suggest that O-GlcNAc modification of proteins can induce insulin resistance in skeletal muscle independent of attenuated phosphorylation of Akt, GSK3α, GSK3β, and a 160-kDa protein with an Akt phosphomotif.

収録刊行物

• Diabetes

  Diabetes 53 (4), 921-930, 2004-04-01

  American Diabetes Association

キーワード

• Endocrinology, Diabetes and Metabolism
• Internal Medicine

詳細情報

• CRID: 1362544420567411456
• NII論文ID: 30026272179
• DOI: 10.2337/diabetes.53.4.921
• ISSN: 1939327X
• ISSN: 00121797
• Web Site: https://journals.org/diabetes/diabetes/article-pdf/53/4/921/652835/zdb00404000921.pdf
• Web Site: https://diabetesjournals.org/diabetes/article-pdf/53/4/921/652835/zdb00404000921.pdf
• データソース種別:
  • Crossref
  • CiNii Articles