Cardiovascular disease (CVD) is the leading cause of death in the United States. Aging is the major risk factor for development of CVD. The major age-related arterial phenotypes, which are thought to be responsible for the development of CVD in older adults, are reduced endothelial function and enhanced large artery stiffness. Recently, it has been demonstrated that inhibition of the mTOR signaling pathway, via rapamycin or genetic manipulation, extends lifespan and reduces age-related physiological dysfunction. The proposed studies aim to determine (a) if increased mTOR signaling is responsible for age-related arterial dysfunction and (b) whether dietary rapamycin treatment and activation of AMPK, a putative """"""""rapalog"""""""", can reverse age-related arterial dysfunction. Our laboratory has performed preliminary studies suggesting that arterial activation of mTOR is increased with advancing age and that this is concomitant with age-associated endothelial dysfunction and large artery stiffening known to result from increases in oxidative stress and inflammation. Furthermore, dietary treatment of old mice with mTOR inhibitor, rapamycin, can reverse this age-associated arterial phenotype and improve arterial function. In the present application, by utilizing dietary rapamycin treatment, we will directly assess the role that mTOR plays in modulating transcription factor activity and downstream gene/protein expression and the subsequent effects on arterial phenotype and function. In addition, we will determine if pharmacological activation of AMPK by AICAR will act as a """"""""rapalog,"""""""" mimicking the effects of rapamycin-induced mTOR inhibition on arterial function and phenotype.

Public Health Relevance

Advancing age is associated with arterial dysfunction. The proposed studies aim to determine if elevated arterial mTOR signaling contributes to dysfunction. In addition, we will determine if rapamycin or a rapalog, the AMPK activator AICAR, can reverse age-related arterial dysfunction and the cellular and molecular mechanisms involved.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AG043952-02
Application #
8726271
Study Section
Aging Systems and Geriatrics Study Section (ASG)
Program Officer
Kohanski, Ronald A
Project Start
2013-09-01
Project End
2015-05-31
Budget Start
2014-06-01
Budget End
2015-05-31
Support Year
2
Fiscal Year
2014
Total Cost
$223,500
Indirect Cost
$73,500
Name
University of Utah
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
009095365
City
Salt Lake City
State
UT
Country
United States
Zip Code
84112
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