RESUMEN
Regardless of its effect on the concentrations of serum cholesterol, statins exert pleiotropic effects, including the regulation of endothelial function, reduced oxidative stress and inflammation, as well as a slight improvement in the concentrations of high density lipoprotein (HDL). However, its role on the composition of HDL is not yet established. The aim of this study was to evaluate the composition of HDL subfractions, HDLsub>2 and HDL3, after 14 days of placebo and atorvastatin (10 mg/day) use in 30 asymptomatic volunteers. The serum parameters and the HDL subfractions compositions were determined using radiometric, nephelometric and biochemical enzymatic methods. We observed significant reductions of total cholesterol, low density lipoprotein (LDL) and apolipoprotein B-100 by 28%, 40% and 38%, respectively. The analyses of chemical composition of the subfractions revealed a lower lipid protein ratio in HDL2, suggesting enrichment in proteins, and also lower in HDL3, probably by an increase in the number of particles. Several mechanisms can be suggested for the effects observed after the use of atorvastatin, such as a possible action on the reverse cholesterol transport (decreased activity of hepatic lipase and increased phospholipid transfer protein, PLTP), which would explain the enrichment of HDL. The results suggest that statin use may be relevant in the primary prevention of atherosclerosis not only by its lowering effect on LDLcholesterol and its anti-inflammatory effect but also by beneficial changes in HDL subfractions.
Asunto(s)
Ácidos Heptanoicos/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Lipoproteínas HDL2/análisis , Lipoproteínas HDL3/análisis , Pirroles/farmacología , Adulto , Atorvastatina , Humanos , MasculinoRESUMEN
BACKGROUND: Cholesteryl ester transfer protein (CETP) plays a major role in lipid metabolism, but studies on the association of CETP polymorphisms with risks of cardiovascular disease are inconsistent. This study investigated whether the CETP gene I405V and Taq1B polymorphisms modified subclinical atherosclerosis in an asymptomatic Brazilian population sample. METHODS: The polymorphisms were analyzed using polymerase chain reaction in 207 adult volunteers. Serum lipid profiles, oxLDL Ab titers, C-reactive protein and tumor necrosis factor-α concentrations and CETP and phospholipid transfer protein (PLTP) activities were determined, and common carotid artery intima-media thickness (cIMT) was measured using ultrasonography. RESULTS: No differences in cIMT were observed between the presence or absence of the minor B2 and V alleles in either polymorphism. However, inverse correlations between mean cIMT and CETP activity in the presence of these polymorphisms were observed, and positive correlations of these polymorphisms with PLTP activity and oxLDL Ab titers were identified. Moreover, logistic multivariate analysis revealed that the presence of the B2 allele was associated with a 5.1-fold (CI 95%, OR: 1.26 - 21.06) increased risk for cIMT, which was equal and above the 66th percentile and positively interacted with age. However, no associations with the V allele or CETP and PLTP activities were observed. CONCLUSIONS: None of the studied parameters, including CETP activity, explained the different relationships between these polymorphisms and cIMT, suggesting that other non-determined factors were affected by the genotypes and related to carotid atherosclerotic disease.