The central hypothesis to be tested in this proposal is that binding of saturated fatty acid to SR-BI activates AMP kinase which results in the production of eNOS-dependent peroxynitrite and subsequently an increase in atherosclerotic lesions. Reducing total dietary fat intake has been used as a method for reducing the risk of coronary heart disease for decades; however, numerous studies have demonstrated that the type of fat may be more important than the total amount of fat in the diet. Unsaturated fats, such as, n-3 and n-6 fatty acids are thought to be anti-atherogenic whereas saturated fatty acids with 14-16 carbon atoms (i.e., myristic acid and palmitic acid) are considered to be pro-atherogenic. Saturated fatty acids are thought to be pro-atherogenic, in part, by causing an increase in total plasma cholesterol levels. Although plasma cholesterol levels clearly influence the development of atherosclerotic lesions cholesterol is only one factor in the multi-factorial disease of atherosclerosis. Our preliminary studies demonstrate that saturated fatty acid can cause an increase in atherosclerosis independent of changes in plasma cholesterol levels. The goal of this proposal is to determine the mechanism whereby saturated fatty acid promotes atherosclerosis without altering plasma cholesterol. The preliminary data suggest that a novel signaling mechanism exists for saturated fatty acids that involve SR-BI, caveolin, AMP kinase, and eNOS which subsequently results in the generation of the pro- atherogenic compound, peroxynitrite.
Three specific aims are proposed.
Aim 1 : To determine the domains within SR-BI that interact with saturated fatty acids and caveolin and to determine the domain within caveolin that interacts with SR-BI.
Aim 2 : To elucidate the residue(s) in caveolin that are phosphorylated and the domains within caveolin and AMP kinase that interact.
Aim 3 : To determine if an endothelial-specific caveolin null mouse is protected from saturated fatty acid-induced peroxynitrite production and subsequently atherosclerosis. ? ? ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL078976-02
Application #
7208080
Study Section
Vascular Cell and Molecular Biology Study Section (VCMB)
Program Officer
Ershow, Abby
Project Start
2006-03-15
Project End
2011-02-28
Budget Start
2007-03-01
Budget End
2008-02-29
Support Year
2
Fiscal Year
2007
Total Cost
$355,629
Indirect Cost
Name
University of Kentucky
Department
Pediatrics
Type
Schools of Medicine
DUNS #
939017877
City
Lexington
State
KY
Country
United States
Zip Code
40506
Zhai, Jianjun; Ström, Anna-Lena; Kilty, Renee et al. (2009) Proteomic characterization of lipid raft proteins in amyotrophic lateral sclerosis mouse spinal cord. FEBS J 276:3308-23
Thomas, Candice M; Smart, Eric J (2008) Caveolae structure and function. J Cell Mol Med 12:796-809