Administration of antioxidant vitamins does not alter plasma fibrinolytic activity in subjects with central obesity

• Published in: Thrombosis and haemostasis Vol. 78; no. 3; p. 1111
• Main Authors: Rifici, V A, Schneider, S H, Chen, Y, Khachadurian, A K
• Format: Journal Article
• Language: English
• Published: Germany 01-09-1997
• Subjects: Antioxidants - pharmacology; Ascorbic Acid - blood; Blood Glucose - analysis; Fibrinolysis - drug effects; Humans; Lipoproteins, LDL - blood; Lipoproteins, VLDL - blood; Male; Obesity - physiopathology; Plasminogen Activator Inhibitor 1 - blood; Tissue Plasminogen Activator - metabolism; Trinitrobenzenesulfonic Acid - analysis; Vitamins - pharmacology
• ISSN: 0340-6245
• DOI: 10.1055/s-0038-1657695

In vitro studies suggest that oxidized low density lipoprotein inhibits fibrinolysis by stimulating the production of plasminogen activator inhibitor -1 (PAI). We assessed the effects of dietary antioxidant vitamins for four weeks on three indices of copper mediated oxidation of very low and low density lipoproteins (VLDL+LDL) and plasma fibrinolytic activities in 15 male subjects with central obesity, a condition associated with increased PAI activity. Vitamin administration resulted in a decrease in production of thiobarbituric acid reactive substances from 29.3 +/- 3.9 to 13.6 +/- 3.5 nmoles/mg VLDL + LDL protein (mean +/- SE, p <0.003), an increase in the lag phase of conjugated diene formation from 94.8 +/- 5.5 to 225.0 +/- 31.9 min (p <0.001) and an increase in reactivity of lysine residues from 73.6% +/- 4.8% to 86.8% +/- 3.6% (p <0.034) demonstrating a reduction in the susceptibility of the lipoproteins to oxidation. However, antioxidant vitamins had no effect on plasma PAI activity, PAI antigen, tissue-type plasminogen activator activity and antigen, fibrinogen and fibrin degradation products. These results do not support the hypothesis that lipoprotein oxidation is a significant cause of impaired fibrinolysis in men with central obesity.