|
|
||||||||
1 Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin 53706; and 2 Howard Hughes Medical Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
Insulin stimulates muscle and adipose tissue to absorb glucose through a signaling cascade that is incompletely understood. Insulin resistance, the inability of insulin to appropriately stimulate glucose uptake, is a hallmark of type 2 diabetes mellitus. The development of experimental systems that model human insulin resistance is important in elucidating the defects responsible for the development of type 2 diabetes. When two strains of mice, BTBR and C57BL/6J (B6), are crossed, the resultant male offspring (BtB6) demonstrate insulin resistance in muscle tissue. Here, we report an insulin resistance phenotype in adipose tissue from lean, nondiabetic BtB6 mice similar to that observed in human muscle. Adipocytes isolated from insulin-resistant male mice display 65% less insulin-stimulated glucose uptake compared with insulin-sensitive female mice. Similarly, adipocytes from insulin-resistant mice have diminished insulin-stimulated IRS-1 phosphorylation and phosphatidylinositol 3-kinase (PI3K) activation. However, normal activation of protein kinase B (Akt/PKB) by insulin is observed. Thus BtB6 mice demonstrate the dissociation of insulin-stimulated PI3K activity and Akt/PKB activation and represent a useful model to investigate the causes of insulin resistance in humans.
protein kinase B; phosphatidylinositol 3-kinase
This article has been cited by other articles:
![]() |
A. L Rodrigues, E. P G De Souza, S. V Da Silva, D. S B Rodrigues, A. B Nascimento, C. Barja-Fidalgo, and M. S De Freitas Low expression of insulin signaling molecules impairs glucose uptake in adipocytes after early overnutrition J. Endocrinol., December 1, 2007; 195(3): 485 - 494. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. Hoy, C. R. Bruce, A. Cederberg, N. Turner, D. E. James, G. J. Cooney, and E. W. Kraegen Glucose infusion causes insulin resistance in skeletal muscle of rats without changes in Akt and AS160 phosphorylation Am J Physiol Endocrinol Metab, November 1, 2007; 293(5): E1358 - E1364. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. B. Flowers, M. E. Rabaglia, K. L. Schueler, M. T. Flowers, H. Lan, M. P. Keller, J. M. Ntambi, and A. D. Attie Loss of Stearoyl-CoA Desaturase-1 Improves Insulin Sensitivity in Lean Mice but Worsens Diabetes in Leptin-Deficient Obese Mice Diabetes, May 1, 2007; 56(5): 1228 - 1239. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Le Foll, C. Corporeau, V. Le Guen, J.-P. Gouygou, J.-P. Berge, and J. Delarue Long-chain n-3 polyunsaturated fatty acids dissociate phosphorylation of Akt from phosphatidylinositol 3'-kinase activity in rats Am J Physiol Endocrinol Metab, April 1, 2007; 292(4): E1223 - E1230. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. B. Flowers, A. T. Oler, S. T. Nadler, Y. Choi, K. L. Schueler, B. S. Yandell, C. M. Kendziorski, and A. D. Attie Abdominal obesity in BTBR male mice is associated with peripheral but not hepatic insulin resistance Am J Physiol Endocrinol Metab, March 1, 2007; 292(3): E936 - E945. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Shetty, E. R.M. Eckhardt, S. R. Post, and D. R. van der Westhuyzen Phosphatidylinositol-3-Kinase Regulates Scavenger Receptor Class B Type I Subcellular Localization and Selective Lipid Uptake in Hepatocytes Arterioscler. Thromb. Vasc. Biol., September 1, 2006; 26(9): 2125 - 2131. [Abstract] [Full Text] [PDF] |
||||
![]() |
F Sentinelli, E Filippi, M G Cavallo, S Romeo, M Fanelli, and M G Baroni The G972R variant of the insulin receptor substrate-1 gene impairs insulin signaling and cell differentiation in 3T3L1 adipocytes; treatment with a PPAR{gamma} agonist restores normal cell signaling and differentiation J. Endocrinol., February 1, 2006; 188(2): 271 - 285. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. E. Rabaglia, M. P. Gray-Keller, B. L. Frey, M. R. Shortreed, L. M. Smith, and A. D. Attie {alpha}-Ketoisocaproate-induced hypersecretion of insulin by islets from diabetes-susceptible mice Am J Physiol Endocrinol Metab, August 1, 2005; 289(2): E218 - E224. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Sugita, M. Kaneki, M. Sugita, T. Yasukawa, S. Yasuhara, and J. A. J. Martyn Burn injury impairs insulin-stimulated Akt/PKB activation in skeletal muscle Am J Physiol Endocrinol Metab, March 1, 2005; 288(3): E585 - E591. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. E. McCurdy, R. T. Davidson, and G. D. Cartee Brief calorie restriction increases Akt2 phosphorylation in insulin-stimulated rat skeletal muscle Am J Physiol Endocrinol Metab, October 1, 2003; 285(4): E693 - E700. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Sakamoto, M. F. Hirshman, W. G. Aschenbach, and L. J. Goodyear Contraction Regulation of Akt in Rat Skeletal Muscle J. Biol. Chem., March 29, 2002; 277(14): 11910 - 11917. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |