Effects of exercise on the development of atherosclerosis in apolipoprotein E-deficient mice.

It has already been shown that mild to moderate exercise training may protect against the development of atherosclerosis. However, the precise mechanisms behind this protection are still unknown. The hypothesis that exercise training reduces the severity of experimental atherosclerosis in apolipoprotein (apo) E-deficient mice was assessed. Swimming training was conducted three times per week for 20 min on apo E-deficient mice fed a high-fat diet for eight or 16 weeks. Atherosclerotic lesions were evaluated. Fatty streak formation and fibrofatty plaques developed in apo E-deficient mice fed the high-fat diet, and were markedly suppressed in mice that received exercise for eight or 16 weeks compared with in nonexercise mice. Differences in lesion area did not correlate with any significant alterations in serum lipid levels. Thus, exercise therapy markedly suppressed experimental atherosclerosis.