Recent findings suggest that apoptosis or programmed cell death contributes to diabetic neuropathy, and, moreover, treatment with IGF-1 protects nerves by inhibiting glucose-induced apoptosis, apparently by signaling through the IGF-1 receptor, phosphatidylinositol 3-kinase (PI3K) and Akt. Akt in turn appears to phosphorylate and inhibit BAD, thereby interrupting an otherwise constitutive interaction of BAD with Bcl-xL, thereby freeing up Bcl-xL, which maintains mitochondrial integrity and prevents apoptosis. The present proposal will test this hypothesis in neural cells in three ways: (1) determine the role of IGF-I receptor-dependent signaling cascades in IGF-1 mediated neuroprotection; (2) examine the function of BAD phosphorylation and BAD/Bcl-xL association in IGF-mediated neuroprotection; and (3) characterize neuronal apoptosis and clinical endpoints of diabetic neuropathy in streptozotocin-diabetic rats treated with IGF-1. The ultimate goal is to understand the pathogenesis of diabetic neuropathy, and develop new treatment strategies for this problem.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS038849-02
Application #
2892486
Study Section
Special Emphasis Panel (ZRG2-NMS (01))
Program Officer
Nichols, Paul L
Project Start
1998-09-30
Project End
2001-08-31
Budget Start
1999-09-01
Budget End
2001-08-31
Support Year
2
Fiscal Year
1999
Total Cost
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Neurology
Type
Schools of Medicine
DUNS #
791277940
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
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Sullivan, Kelli A; Lentz, Stephen I; Roberts Jr, John L et al. (2008) Criteria for creating and assessing mouse models of diabetic neuropathy. Curr Drug Targets 9:3-13

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