LDL particle size and composition and incident cardiovascular disease in a South-European population: The Hortega-Liposcale Follow-up Study.

BACKGROUND: The association of low-density lipoprotein (LDL) particle composition with cardiovascular risk has not been explored before. The aim was to evaluate the relationship between baseline LDL particle size and composition (proportions of large, medium and small LDL particles over their sum expressed as small-LDL %, medium-LDL % and large-LDL %) and incident cardiovascular disease in a population-based study. METHODS: Direct measurement of LDL particles was performed using a two-dimensional NMR-technique (Liposcale®). LDL cholesterol was assessed using both standard photometrical methods and the Liposcale® technique in a representative sample of 1162 adult men and women from Spain. RESULTS: The geometric mean of total LDL particle concentration in the study sample was 827.2 mg/dL (95% CI 814.7, 839.8). During a mean follow-up of 12.4 ±â€¯3.3 years, a total of 159 events occurred. Medium LDL particles were positively associated with all cardiovascular disease, coronary heart disease (CHD) and stroke after adjustment for traditional risk factors and treatment. Regarding LDL particle composition, the multivariable adjusted hazard ratios for CHD for a 5% increase in medium and small LDL % by a corresponding decrease of large LDL % were 1.93 (1.55, 2.39) and 1.41 (1.14, 1.74), respectively. CONCLUSIONS: Medium LDL particles were associated with incident cardiovascular disease. LDL particles showed the strongest association with cardiovascular events when the particle composition, rather than the total concentration, was investigated. A change in baseline composition of LDL particles from large to medium and small LDL particles was associated with an increased cardiovascular risk, especially for CHD.

Soy-derived phytoestrogens as preventive and acute neuroprotectors in experimental ischemic stroke: influence of rat strain.

The ability of a soy-based high-phytoestrogen diet (nutritional intervention) or genistein (pharmacological intervention), to limit ischemic brain damage in Wistar, Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats, has been assessed. As to the nutritional intervention, two groups from each strain received either a phytoestrogen-free (PE-0) or a high-phytoestrogen (PE-600) diet from weaning to adulthood. As to the pharmacological intervention, all animals were fed the standard soy-free AIN-93G diet and subsequently separated into two groups from each strain to receive either pure genistein (aglycone form, 1mg/kg/day intraperitoneal) or vehicle at 30 min reperfusion. After an episode of 90 min ischemia (intraluminal thread procedure) followed by 3 days reperfusion, cerebral infarct volume was measured. Arterial blood pressure (ABP) was significantly higher at the basal stage (just before ischemia) in SHR (140 ± 7 mmHg, n=17, p<0.05) than in Wistar (113 ± 4mmHg, n=23) and WKY (111 ± 6mmHg, n=14) rats. No significant differences were shown among the three stages (basal, ischemia, reperfusion) within each rat strain for both PE-0 and PE-600 diets. Wistar, but not WKY or SHR, rats fed the PE-600 diet showed significantly lower infarct volumes than their counterparts fed the PE-0 diet (30 ± 3% vs. 17 ± 3%, p<0.01). Genistein-treated Wistar, but not WKY or SHR, rats showed significantly lower infarct volumes than their vehicle-treated controls (27 ± 2% vs. 15 ± 2%, p<0.01). Our results demonstrate that: (1) the neuroprotective action of either chronic or acute exposure to soy isoflavones is strain-dependent, since it was shown in Wistar but not WKY or SHR rats; and (2) the soy-based diet does not prevent development of hypertension in SHR rats.