A joint project of the Graduate School, Peabody College, and the Jean & Alexander Heard Library

Title page for ETD etd-03122015-115410


Type of Document Dissertation
Author Williams, Ashley Silberman
Author's Email Address ashley.s.williams@vanderbilt.edu
URN etd-03122015-115410
Title Integrin Signaling is a Novel Regulator of Hepatic Insulin Action
Degree PhD
Department Molecular Physiology and Biophysics
Advisory Committee
Advisor Name Title
Dr. Maureen Gannon Committee Chair
Dr. Alan D. Cherrington Committee Member
Dr. Ambra Pozzi Committee Member
Dr. John Stafford Committee Member
Keywords
  • integrin
  • extracellular matrix
  • liver
  • insulin
Date of Defense 2015-02-26
Availability unrestricted
Abstract
The prevalence of type 2 diabetes has increased dramatically in parallel with excess caloric intake and sedentary lifestyles. Insulin resistance precedes the development of type 2 diabetes. The liver is a major insulin-responsive organ, thus defects in liver insulin action contribute greatly to the insulin resistant state. Hepatic insulin resistance is associated with increased deposition of extracellular matrix proteins such as collagen. Integrin α1β1 is a collagen binding integrin found on hepatocytes. Results from the Dissertation show that integrin α1 is upregulated in hepatocytes during times of nutritional overload and this exerts a protective effect against the development of hepatic insulin resistance in high fat fed mice. Moreover, a downstream integrin signaling molecule, integrin-linked kinase, is also involved in the regulation of hepatic insulin action. The hepatocyte-specific deletion of integrin-linked kinase protects against hepatic insulin resistance in high fat fed mice. The effects of integrin α1β1 and integrin-linked kinase on hepatic insulin sensitivity were independent of their effects on hepatic lipid accumulation. This was evident as results show that integrins promote hepatic lipid accumulation in high fat fed mice regardless of insulin sensitivity. Collectively, these are the first studies to demonstrate a mechanistic link between integrins and hepatic insulin action in vivo. The data within the Dissertation open new avenues for investigation in a novel area of metabolic research and identify innovative therapeutic targets to treat the underlying insulin resistance associated with type 2 diabetes.
Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  Williams.pdf 4.28 Mb 00:19:49 00:10:11 00:08:55 00:04:27 00:00:22

Browse All Available ETDs by ( Author | Department )

If you have more questions or technical problems, please Contact LITS.