The prevention of endothelial dysfunction through endothelial cell apoptosis inhibition in a hypercholesterolemic rabbit model: the effect of L-arginine supplementation.
BACKGROUND
The impact of L-arginine on atherogenesis and its ability to prevent endothelial dysfunction have been studied extensively during the past years. L-arginine is a substance for nitric oxide synthesis which involves in apoptosis. Hypercholesterolemia promotes endothelial dysfunction, and it is hypothesized that L-arginine prevents endothelial dysfunction through endothelial cells apoptosis inhibition. To test this hypothesis, thirty rabbits were assigned into two groups. The control group received 1% cholesterol diet for 4 weeks, and the L-arginine group received same diets plus 3% L-arginine in drinking water.


RESULTS
No significant differences were observed in cholesterol level between two groups, but the nitrite concentration in L-arginine group was significantly higher than other group (control group: 11.8 +/- 1; L-arginine group: 14.7 +/- 0.5 micromol/l); (p < 0.05). The aorta score of fatty streak in control group was 0.875 +/- 0.35, but no fatty streak lesion was detected in L-arginine group (p < 0.05). The number of intimal apoptotic cells/500 cells of aorta in two groups of experiment were statistically different (control group: 39.3 +/- 7.6; L-arginine group: 21.5 +/- 5.3) (p < 0.05).


CONCLUSIONS
The inhibition of endothelial cells apoptosis by L-arginine restores endothelial function in a model of hypercholesterolemia.
Nematbakhsh
Mehdi
M
Deparment of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran. nematbakhsh@gmail.com
Haghjooyjavanmard
Shaghayegh
S
Mahmoodi
Farzaneh
F
Monajemi
Ali Reza
AR
D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000473:pathology; D017209:Apoptosis / Q000187:drug effects*; D001120:Arginine / Q000008:administration & dosage / Q000494:pharmacology*; D050197:Atherosclerosis / Q000473:pathology; D002452:Cell Count; D002784:Cholesterol / Q000097:blood; D019587:Dietary Supplements; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000187:drug effects* / Q000473:pathology*; D006937:Hypercholesterolemia / Q000503:physiopathology* / Q000517:prevention & control*; D020287:In Situ Nick-End Labeling; D008297:Male; D009573:Nitrites / Q000097:blood; D011817:Rabbits
D009573:Nitrites; D001120:Arginine; D002784:Cholesterol