Effect of a short-term diet and exercise intervention in youth on atherosclerotic risk factors.

Early stages of atherosclerosis are commonly noted in youth. The present study was designed to examine the effects of lifestyle modification in 19 overweight children (age 8-17) who were placed on a high-fiber, low-fat diet in a 2-week residential program where food was provided ad libitum and daily exercise (2-2.5h) was performed. In each subject, pre- and post-intervention fasting blood was drawn to measure serum lipids, oxidative stress marker 8-isoprostaglandin F2alpha (8-iso-PGF2alpha) and generating enzyme myeloperoxidase (MPO), soluble intracellular adhesion molecule (sICAM)-1 and sE-selectin as indicators of endothelial activation, the inflammatory protein C-reactive protein (CRP) and total matrix metalloproteinase-9 (MMP-9). Using subject sera and human aortic endothelial cell (HAEC) culture systems, monocyte chemotactic protein-1 (MCP-1) production, as well as nitric oxide (NO), superoxide and hydrogen peroxide production were measured in vitro by fluorometric detection. After 2 weeks, significant reductions (p<0.05) in all serum lipids (except HDL cholesterol), 8-iso-PGF2alpha, MPO, sICAM-1, sE-selectin, CRP, MMP-9, and cellular MCP-1 production were noted. Additionally, there was a significant decrease in cultured, serum-stimulated HAEC production of superoxide and hydrogen peroxide, and a concomitant increase in NO production (all p<0.01), These results indicate amelioration of several traditional as well as novel factors associated with atherosclerosis after lifestyle modification, even in youth without documented disease.