Higher glutathione peroxidase expression in thoracic aorta as a protective factor against oxidative stress and atherosclerosis in rabbits.
OBJECTIVE
Atherosclerosis develops in different locations of the vasculature with different degree, which may result from different antioxidant/prooxidant status. This study investigated the effect of high-fat, high-cholesterol chows, with or without vitamin E supplement (450 mg/kg diet), on lipid peroxide levels, glutathione peroxidase expression, and atheroma formation in ascending aorta, pulmonary arteries and thoracic aorta.


METHODS
Sixty-four rabbits were divided to be fed with 4 different chows for 6 weeks. The percentage of atherosclerosis was measured. Plasma and vascular glutathione peroxidase activity and mRNA expression, and lipid peroxide levels were also assayed.


RESULTS
Rabbits on high-fat, high-cholesterol chows had higher lipid peroxide levels and more atherosclerosis in ascending aorta and pulmonary arteries. Tissues in thoracic aorta had higher glutathione peroxidase activity and mRNA expression without any significant increase in lipid peroxide levels and atherosclerosis. Vitamin E supplement decreased plasma lipid peroxide levels, but not in tissues, and thus could not prevent atherosclerosis.


CONCLUSIONS
Higher glutathione peroxidase expression in the thoracic aorta inhibits oxidative stress enhancement and atheroma progression induced by high-fat, high-cholesterol chows. Vitamin E supplement at the current dosage and duration could not prevent atheroma formation.
Lin
Mao-Shin
MS
Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Douliou City, Taiwan.
Hsu
Hsiu-Ching
HC
Lin
Lung-Chun
LC
Li
Hung-Yuan
HY
Lee
Bai-Chin
BC
Lee
Yuan-Teh
YT
Chen
Ming-Fong
MF
D000818:Animals; D001011:Aorta / Q000378:metabolism; D001013:Aorta, Thoracic / Q000378:metabolism*; D050197:Atherosclerosis / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D002791:Cholesterol, Dietary / Q000009:adverse effects; D004036:Diet, Atherogenic; D004041:Dietary Fats / Q000009:adverse effects; D019587:Dietary Supplements; D005979:Glutathione Peroxidase / Q000096:biosynthesis*; D018384:Oxidative Stress / Q000502:physiology*; D011651:Pulmonary Artery / Q000378:metabolism; D011817:Rabbits; D014810:Vitamin E / Q000627:therapeutic use*
D002791:Cholesterol, Dietary; D004041:Dietary Fats; D014810:Vitamin E; D005979:Glutathione Peroxidase