Susceptibility of apolipoprotein B-containing lipoproteins to oxidation and antioxidant status in acute coronary syndromes.
BACKGROUND
Oxidized lipoproteins may play an important role in the pathogenesis of atherosclerosis, and it has been shown that antioxidants have a protective effect against the progression of atherosclerosis.


OBJECTIVE
The aim of this study was to investigate the oxidative susceptibility of apolipoprotein B-containing lipoproteins and antioxidant status in patients with acute coronary syndromes and chronic stable angina pectoris.


METHODS
The study population included 70 patients with acute coronary syndromes (14 with recent acute myocardial infarction and 56 with unstable angina pectoris), 105 patients with stable angina pectoris, and 75 control subjects. In addition to conventional lipid and lipoprotein analysis, the susceptibility of apolipoprotein B-containing lipoproteins to in vitro oxidation (lag phase) and plasma vitamin E and total carotene levels was measured.


RESULTS
The lag phase was significantly shorter in patients with acute coronary syndromes (45 +/- 12 min) than in patients with stable angina pectoris (51 +/- 10 min) and in control subjects (58 +/- 9 min) (p < 0.0001). Both plasma vitamin E and total carotene levels were lowest in patients with acute coronary syndromes (1.11 +/- 0.32 mg/dl and 119 +/- 32 micrograms/dl, respectively), followed by patients with stable angina pectoris (1.25 +/- 0.37 mg/dl and 132 +/- 37 micrograms/dl) and then controls (1.52 +/- 0.31 mg/dl and 167 +/- 41 micrograms/dl).


CONCLUSIONS
These data suggest that there is an intense oxidative process and a lower antioxidant status in acute coronary syndromes. This may lead to plaque instability due to the activation of the inflammatory response in coronary atherosclerotic lesions.
Yesilbursa
D
D
Uludag University, Medical Faculty, Department of Cardiology, Bursa, Turkey.
Serdar
Z
Z
Dirican
M
M
Serdar
A
A
Güllülü
S
S
Cordan
J
J
D000368:Aged; D000787:Angina Pectoris / Q000378:metabolism; D000789:Angina, Unstable / Q000378:metabolism; D001055:Apolipoproteins B / Q000378:metabolism*; D002338:Carotenoids / Q000097:blood; D008078:Cholesterol, LDL / Q000378:metabolism; D015243:Cholesterol, VLDL / Q000378:metabolism; D002908:Chronic Disease; D003327:Coronary Disease / Q000209:etiology / Q000378:metabolism*; D005260:Female; D006801:Humans; D008074:Lipoproteins / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000378:metabolism; D010084:Oxidation-Reduction; D013997:Time Factors; D014810:Vitamin E / Q000097:blood
D001055:Apolipoproteins B; D008078:Cholesterol, LDL; D015243:Cholesterol, VLDL; D008074:Lipoproteins; D014810:Vitamin E; D002338:Carotenoids