Fluvastatin depresses the enhanced lipid peroxidation in vitamin E-deficient hamsters

Dietary fat type affects vitamins C and E and biomarkers of oxidative status in peripheral and brain tissues of golden Syrian hamsters

Oxidative stress is an important trigger in the complex chain of events leading to neurodegenerative diseases. On the other hand, dietary fatty acids play an essential role in brain function. The objectives of this study were to assess the effect of dietary fat type on vitamin C and vitamin E (alpha-and gamma-tocopherol) concentrations in peripheral and brain tissues and its effect on 8-epiPGF(2)alpha (F(2)-isoprostanes). Male Golden Syrian hamsters (n = 120, 8 wk old) were fed diets enriched in butter, hydrogenated fat (margarine), and canola and soybean oils. After 12 wk, hamsters were deprived of food, anesthetized with isoflurane, and killed via terminal exsanguination. Analyses of vitamins C, E, and 8-epiPGF(2)alpha were performed in peripheral tissues and brain. Hamsters consuming the margarine-enriched diet had lower (P < 0.05) vitamin C and alpha-tocopherol concentrations in liver, plasma, and brain, and higher (P < 0.02) plasma 8-epiPGF(2)alpha than groups fed the butter, and the canola and soybean oil diets. Liver and plasma gamma-tocopherol concentration was higher (P < 0.001) among the groups fed the soybean- and margarine-enriched diets compared with the other groups. alpha-Tocopherol was higher (P < 0.05) and 8-epiPGF(2)alpha lower (P < 0.01) among the groups fed the canola and soybean oil diets compared with the other groups. Across the groups, an inverse correlation between plasma levels of vitamin C and 8-epiPGF(2)alpha (r = -0.37, P = 0.03) and a positive correlation between plasma levels of vitamin C and alpha-tocopherol were observed (r = 0.341, P = 0.003). Hamsters fed the butter-enriched diet had a higher (P < 0.03) plasma uric acid concentration than the other groups. The results of this study provide new evidence concerning the effect of dietary fat on antioxidant status, which is important for the maintenance of good health.

Long-Term Treatment with Probucol Improves Endothelial Function in Patients with Coronary Artery Disease

Recent studies have shown that endothelial function is impaired in patients with coronary artery disease (CAD). Probucol has been recognized to have antioxidant properties as well as lipid-lowering effects, and may improve endothelial function. The aim of this study was to evaluate the effects of probucol on endothelial function in patients with CAD. We evaluated endothelial function, based on flow-mediated vasodilation during reactive hyperemia (FMD), and the intima-media thickness (IMT) of the common carotid artery using high resolution ultrasonography in patients either with (CAD group, n=26) or without CAD (Control group, n=12). We measured the serum cholesterol concentration, including the low-density lipoprotein cholesterol (LDL-cholesterol) concentration, and the plasma concentrations of homocyst(e)ine and asymmetric dimethylarginine (ADMA). Measurements of FMD and serum cholesterol were repeated after 3 months of probucol (500 mg/day, n=9) or placebo (n=9) treatment in patients with CAD. The IMT was significantly greater (p < 0.001) and FMD was significantly lower (p < 0.001) in the CAD group than in the Control group. While the serum cholesterol concentration and plasma ADMA were similar in the two groups, the plasma homocyst(e)ine concentrations were higher in the CAD group than in the Control group (p < 0.01). After probucol therapy, FMD was significantly improved in the CAD group (p < 0.05). The serum LDL-cholesterol concentration did not significantly decrease after probucol treatment. Placebo treatment did not alter FMD or the serum cholesterol concentration. Our findings suggest that long-term treatment with probucol improves endothelial function in patients with CAD, an outcome independent of the LDL-cholesterol-lowering effects of probucol, and that homocyst(e)ine may be a better predictor of atherosclerosis than ADMA.

Inhibition of the thrombogenic and inflammatory properties of antiphospholipid antibodies by fluvastatin in an in vivo animal model

OBJECTIVE

Antiphospholipid antibodies (aPL) have thrombogenic properties in vivo, through their interactions with soluble coagulation factors and their ability to modulate the functions of cells involved in coagulation homeostasis. These antibodies have also been shown to enhance the adhesion of leukocytes to endothelial cells (ECs) in vivo. New lipophilic statins such as fluvastatin have antiinflammatory and antithrombogenic effects. This study uses an in vivo mouse model to investigate whether fluvastatin has an effect on decreasing both the adhesion of leukocytes to ECs and the thrombus formation induced by aPL.

METHODS

Two groups of CD-1 male mice, each comprising approximately 18 mice, were fed either normal saline solution or 15 mg/kg fluvastatin for 15 days. Each of the 2 groups was further subdivided to receive either purified IgG from patients with the antiphospholipid syndrome (IgG-APS) or normal IgG from healthy subjects. Analysis of thrombus dynamics was performed in treated and control mice, using a standardized thrombogenic injury procedure, and the area (size) of the thrombus was measured. Adhesion of leukocytes to ECs was analyzed with a microcirculation model of exposed cremaster muscle. Baseline and posttreatment soluble intercellular adhesion molecule 1 (sICAM-1) levels were determined by enzyme-linked immunosorbent assay.

RESULTS

IgG-APS mice treated with fluvastatin showed significantly smaller thrombi, a reduced number of adherent leukocytes, and decreased levels of sICAM-1 compared with IgG-APS animals treated with placebo.

CONCLUSION

These findings indicate that fluvastatin significantly diminishes aPL-mediated thrombosis and EC activation in vivo. These results may have important implications for the design of new treatment strategies aimed at preventing recurrent thrombosis in patients with APS.

Fluvastatin Increases LDL Particle Size and Reduces Oxidative Stress in Patients with Hyperlipidemia

The effects of fluvastatin on levels of urinary 8-iso-prostaglandin F2alpha (iPF2alphaIII), a marker of oxidative stress, and low-density lipoprotein (LDL) particle size in serum were investigated in patients with hypercholesterolemia. After 6 months of fluvastatin therapy, levels of urinary iPF2alphaIII decreased from 1720.1 +/- 392.0 to 539.6 +/- 75.5 pg/mg (p < 0.01), and LDL particle size increased from 24.3 +/- 0.3 to 26.5 +/- 0.2 nm (p < 0.001). These changes from the treatment of fluvastatin were not correlated with those of the serum LDL cholesterol (LDL-C) levels. The results imply that fluvastatin, with its unique antioxidant property among statins, reduces oxidative stress and increases LDL particle size simultaneously in hyperlipidemic patients.