Exercise training reduces severity of atherosclerosis in apolipoprotein E knockout mice via nitric oxide.
BACKGROUND
Exercise training may protect against the development of atherosclerosis, although the precise mechanisms are still unknown. The present study assessed the hypothesis that exercise training would reduce the severity of experimental atherosclerosis in apolipoprotein-E (apoE)-deficient mice via nitric oxide (NO).


RESULTS
ApoE-deficient mice fed a high-fat diet underwent exercise training (30 min swimming) 3 times per week for 8 weeks. The exercise group were also given oral N(G)-nitro-L-arginine methylester (L-NAME; 25 mg x kg (-1) x day(-1)), an inhibitor of NO synthase. Fatty streak plaque lesions developed in ApoE-deficient mice fed the high-fat diet, and were suppressed in the mice that underwent swimming training. In contrast, atherosclerotic lesions were not ameliorated in mice that had exercise training plus oral L-NAME treatment. Immunohistochemical analysis revealed that the expression of endothelial NO increased in mice undergoing exercise compared with the mice that did not exercise, and that the expression was suppressed in the mice having exercise plus oral L-NAME treatment. Differences in lesion area did not correlate with any significant alterations in serum lipid levels.


CONCLUSIONS
Exercise training suppressed atherosclerosis via the NO system.
Shimada
Kana
K
Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Kishimoto
Chiharu
C
Okabe
Taka-aki
TA
Hattori
Miki
M
Murayama
Toshinori
T
Yokode
Masayuki
M
Kita
Toru
T
D000818:Animals; D001057:Apolipoproteins E / Q000235:genetics / Q000502:physiology*; D050197:Atherosclerosis / Q000473:pathology / Q000503:physiopathology* / Q000517:prevention & control*; D001794:Blood Pressure / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D008055:Lipids / Q000097:blood; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D012720:Severity of Illness Index
D001057:Apolipoproteins E; D004791:Enzyme Inhibitors; D008055:Lipids; D009569:Nitric Oxide; D019331:NG-Nitroarginine Methyl Ester