Diabetes 52:935-941, 2003
© 2003 by the American Diabetes Association, Inc.
Defective Signaling Through Akt-2 and -3 But Not Akt-1 in Insulin-Resistant Human Skeletal Muscle
Potential Role in Insulin Resistance
Joseph T. Brozinick, Jr1,
Brian R. Roberts2,3, and
G. Lynis Dohm3
1 Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana
2 East Carolina University School of Medicine, Department of Biochemistry, Greenville, North Carolina
3 Emory University School of Medicine, Atlanta, Georgia
Recent evidence has shown that activation of phosphatidyinositol-3-kinase (PI3K) and Akt, necessary for insulin stimulation of glucose transport, is impaired in insulin resistance. It is unknown, however, which Akt isoform shows impaired activation in insulin resistance. Additionally, related growth factors (epidermal or platelet-derived vascular) also stimulate PI3K, but it is unknown whether production of 3,4,5 phosphatidyinositol is sufficient to stimulate glucose transport in insulin-resistant muscle. Moreover, these studies were performed in rodents, and little data exists from humans. Hence, we investigated the stimulation of PI3K and Akt-1, -2, and -3 by insulin and epidermal growth factors (EGFs) in skeletal muscles from lean and obese insulin-resistant humans. Insulin activated all Akt isoforms in lean muscles, whereas only Akt-1 was activated in obese muscles. Insulin receptor substrate (IRS)-1 was associated with PI3K activity, which is necessary for Akt activation by insulin, and was reduced in obese muscles, and this was accompanied by decreased IRS-1 expression. In contrast, insulin- or EGF-stimulated phosphotyrosine-associated PI3K activity was not different between lean and obese muscles. These results show that a defect in the ability of insulin to activate Akt-2 and -3 may explain the impaired insulin-stimulated glucose transport in insulin resistance. Additionally, these data also show that different upstream or downstream signals may regulate the activity of the various Akt isoforms.

CiteULike Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
C. Le Stunff, A. Dechartres, V. Mariot, C. Lotton, C. Trainor, E. Miraglia Del Giudice, D. Meyre, I. Bieche, I. Laurendeau, P. Froguel, et al.
Association Analysis Indicates That a Variant GATA-Binding Site in the PIK3CB Promoter Is a Cis-Acting Expression Quantitative Trait Locus for This Gene and Attenuates Insulin Resistance in Obese Children
Diabetes,
February 1, 2008;
57(2):
494 - 502.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. D. Wadley, N. Konstantopoulos, L. Macaulay, K. F. Howlett, A. Garnham, M. Hargreaves, and D. Cameron-Smith
Increased insulin-stimulated Akt pSer473 and cytosolic SHP2 protein abundance in human skeletal muscle following acute exercise and short-term training
J Appl Physiol,
April 1, 2007;
102(4):
1624 - 1631.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. Li, R. E. Anderson, H. Tomita, R. Adler, X. Liu, D. J. Zack, and R. V. S. Rajala
Nonredundant Role of Akt2 for Neuroprotection of Rod Photoreceptor Cells from Light-Induced Cell Death
J. Neurosci.,
January 3, 2007;
27(1):
203 - 211.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. E. Cleasby, T. A. Reinten, G. J. Cooney, D. E. James, and E. W. Kraegen
Functional Studies of Akt Isoform Specificity in Skeletal Muscle in Vivo; Maintained Insulin Sensitivity Despite Reduced Insulin Receptor Substrate-1 Expression
Mol. Endocrinol.,
January 1, 2007;
21(1):
215 - 228.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. M. McCarthy, K. O. Spisak, J. T. Brozinick, and J. S. Elmendorf
Loss of cortical actin filaments in insulin-resistant skeletal muscle cells impairs GLUT4 vesicle trafficking and glucose transport
Am J Physiol Cell Physiol,
November 1, 2006;
291(5):
C860 - C868.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. I. Kim, F. N. Lee, W. S. Choi, S. Lee, and J. H. Youn
Insulin Regulation of Skeletal Muscle PDK4 mRNA Expression Is Impaired in Acute Insulin-Resistant States.
Diabetes,
August 1, 2006;
55(8):
2311 - 2317.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. E.N. Reiter, X. Wu, L. Sandirasegarane, M. Nakamura, K. A. Gilbert, R. S.J. Singh, P. E. Fort, D. A. Antonetti, and T. W. Gardner
Diabetes reduces Basal retinal insulin receptor signaling: reversal with systemic and local insulin.
Diabetes,
April 1, 2006;
55(4):
1148 - 1156.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. K. Bandyopadhyay, J. G. Yu, J. Ofrecio, and J. M. Olefsky
Increased p85/55/50 Expression and Decreased Phosphotidylinositol 3-Kinase Activity in Insulin-Resistant Human Skeletal Muscle
Diabetes,
August 1, 2005;
54(8):
2351 - 2359.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. A. Velliquette, J. E. Friedman, J. Shao, B. B. Zhang, and P. Ernsberger
Therapeutic Actions of an Insulin Receptor Activator and a Novel Peroxisome Proliferator-Activated Receptor {gamma} Agonist in the Spontaneously Hypertensive Obese Rat Model of Metabolic Syndrome X
J. Pharmacol. Exp. Ther.,
July 1, 2005;
314(1):
422 - 430.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. K.R. Karlsson, J. R. Zierath, S. Kane, A. Krook, G. E. Lienhard, and H. Wallberg-Henriksson
Insulin-Stimulated Phosphorylation of the Akt Substrate AS160 Is Impaired in Skeletal Muscle of Type 2 Diabetic Subjects
Diabetes,
June 1, 2005;
54(6):
1692 - 1697.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. B. Strawbridge and J. S. Elmendorf
Phosphatidylinositol 4,5-Bisphosphate Reverses Endothelin-1-Induced Insulin Resistance via an Actin-Dependent Mechanism
Diabetes,
June 1, 2005;
54(6):
1698 - 1705.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. J. Herr, J. R. Bernard, D. W. Reeder, D. A. Rivas, J. J. Limon, and B. B. Yaspelkis III
Insulin-stimulated plasma membrane association and activation of Akt2, aPKC {zeta} and aPKC {lambda} in high fat fed rodent skeletal muscle
J. Physiol.,
June 1, 2005;
565(2):
627 - 636.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. E. McCurdy and G. D. Cartee
Akt2 Is Essential for the Full Effect of Calorie Restriction on Insulin-Stimulated Glucose Uptake in Skeletal Muscle
Diabetes,
May 1, 2005;
54(5):
1349 - 1356.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. K.R. Karlsson, K. Hallsten, M. Bjornholm, H. Tsuchida, A. V. Chibalin, K. A. Virtanen, O. J. Heinonen, F. Lonnqvist, P. Nuutila, and J. R. Zierath
Effects of Metformin and Rosiglitazone Treatment on Insulin Signaling and Glucose Uptake in Patients With Newly Diagnosed Type 2 Diabetes: A Randomized Controlled Study
Diabetes,
May 1, 2005;
54(5):
1459 - 1467.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. Sugita, M. Fujimoto, T. Yasukawa, N. Shimizu, M. Sugita, S. Yasuhara, J. A. J. Martyn, and M. Kaneki
Inducible Nitric-oxide Synthase and NO Donor Induce Insulin Receptor Substrate-1 Degradation in Skeletal Muscle Cells
J. Biol. Chem.,
April 8, 2005;
280(14):
14203 - 14211.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. Yamada, S. Okada, T. Saito, K. Ohshima, M. Sato, T. Tsuchiya, Y. Uehara, H. Shimizu, and M. Mori
Akt2 phosphorylates Synip to regulate docking and fusion of GLUT4-containing vesicles
J. Cell Biol.,
March 14, 2005;
168(6):
921 - 928.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. S. Anderson, M. Thamotharan, D. Kao, S. U. Devaskar, L. Qiao, J. E. Friedman, and W. W. Hay Jr
Effects of acute hyperinsulinemia on insulin signal transduction and glucose transporters in ovine fetal skeletal muscle
Am J Physiol Regulatory Integrative Comp Physiol,
February 1, 2005;
288(2):
R473 - R481.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
T. Yuasa, R. Kakuhata, K. Kishi, T. Obata, Y. Shinohara, Y. Bando, K. Izumi, F. Kajiura, M. Matsumoto, and Y. Ebina
Platelet-Derived Growth Factor Stimulates Glucose Transport in Skeletal Muscles of Transgenic Mice Specifically Expressing Platelet-Derived Growth Factor Receptor in the Muscle, but It Does Not Affect Blood Glucose Levels
Diabetes,
November 1, 2004;
53(11):
2776 - 2786.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. A. McIntyre, R. Halse, S. J. Yeaman, and M. Walker
Cultured Muscle Cells from Insulin-Resistant Type 2 Diabetes Patients Have Impaired Insulin, but Normal 5-Amino-4-Imidazolecarboxamide Riboside-Stimulated, Glucose Uptake
J. Clin. Endocrinol. Metab.,
July 1, 2004;
89(7):
3440 - 3448.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. R. Gosmanov, G. E. Umpierrez, A. H. Karabell, R. Cuervo, and D. B. Thomason
Impaired expression and insulin-stimulated phosphorylation of Akt-2 in muscle of obese patients with atypical diabetes
Am J Physiol Endocrinol Metab,
July 1, 2004;
287(1):
E8 - E15.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. D. Krisan, D. E. Collins, A. M. Crain, C. C. Kwong, M. K. Singh, J. R. Bernard, and B. B. Yaspelkis III
Resistance training enhances components of the insulin signaling cascade in normal and high-fat-fed rodent skeletal muscle
J Appl Physiol,
May 1, 2004;
96(5):
1691 - 1700.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Y. Christ-Roberts, T. Pratipanawatr, W. Pratipanawatr, R. Berria, R. Belfort, and L. J. Mandarino
Increased insulin receptor signaling and glycogen synthase activity contribute to the synergistic effect of exercise on insulin action
J Appl Physiol,
December 1, 2003;
95(6):
2519 - 2529.
[Abstract]
[Full Text]
|
 |
|
Copyright © 2003 by the American Diabetes Association.
|
|
| |
|