Enhanced plasma soluble CD40 ligand levels in essential hypertensive patients with blunted nocturnal blood pressure decrease.

BACKGROUND: Hypertensives with a blunted nocturnal blood pressure (BP) decrease have increased risk of developing atherosclerotic disease. Soluble CD40 ligand (sCD40L) is involved in the pathogenesis of risk factor-related vascular damage. Therefore, we evaluated the relationship between circulating sCD40L levels, circadian BP profile, and early carotid atherosclerosis in essential hypertensives. METHODS: Plasma sCD40L concentrations were assessed in two groups of 25 never-treated hypertensives, without additional cardiovascular risk factors, differentiated on the basis of a nocturnal decrease of BP either of >10% (dippers) or <10% (nondippers) of daytime values, and in 25 matched normotensives. Carotid intima-media thickness (IMT) was also measured in all participants. RESULTS: Plasma sCD40L concentrations were higher in nondippers (4.9 +/- 1.2 ng/mL) than in dippers (3.7 +/- 0.7, P = .0005) and controls (1.6 +/- 0.6, P < .0001). These latter had lower sCD40L concentrations than dippers (P < .0001). The IMT was higher in both hypertensive groups than in normotensives (P < .0001). In the entire hypertensive population IMT directly correlated with circulating levels of sCD40L (r = 0.365, P = .01) and inversely correlated with nocturnal systolic BP decreases (r = -0.286, P = .043). In a multivariate regression analysis sCD40L was the main determinant of IMT (r(2) = 0.157, P = .004). CONCLUSIONS: Nondippers have enhanced plasma sCD40L levels, which may contribute to their increased susceptibility to develop vascular damage.

Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensives.

Consumption of flavanol-rich dark chocolate (DC) has been shown to decrease blood pressure (BP) and insulin resistance in healthy subjects, suggesting similar benefits in patients with essential hypertension (EH). Therefore, we tested the effect of DC on 24-hour ambulatory BP, flow-mediated dilation (FMD), and oral glucose tolerance tests (OGTTs) in patients with EH. After a 7-day chocolate-free run-in phase, 20 never-treated, grade I patients with EH (10 males; 43.7+/-7.8 years) were randomized to receive either 100 g per day DC (containing 88 mg flavanols) or 90 g per day flavanol-free white chocolate (WC) in an isocaloric manner for 15 days. After a second 7-day chocolate-free period, patients were crossed over to the other treatment. Noninvasive 24-hour ambulatory BP, FMD, OGTT, serum cholesterol, and markers of vascular inflammation were evaluated at the end of each treatment. The homeostasis model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), and insulin sensitivity index (ISI) were calculated from OGTT values. Ambulatory BP decreased after DC (24-hour systolic BP -11.9+/-7.7 mm Hg, P<0.0001; 24-hour diastolic BP -8.5+/-5.0 mm Hg, P<0.0001) but not WC. DC but not WC decreased HOMA-IR (P<0.0001), but it improved QUICKI, ISI, and FMD. DC also decreased serum LDL cholesterol (from 3.4+/-0.5 to 3.0+/-0.6 mmol/L; P<0.05). In summary, DC decreased BP and serum LDL cholesterol, improved FMD, and ameliorated insulin sensitivity in hypertensives. These results suggest that, while balancing total calorie intake, flavanols from cocoa products may provide some cardiovascular benefit if included as part of a healthy diet for patients with EH.

Effects of bezafibrate and simvastatin on endothelial activation and lipid peroxidation in hypercholesterolemia: evidence of different vascular protection by different lipid-lowering treatments.

Hypercholesterolemia is combined with enhanced lipid peroxidation, which can promote atherogenesis by inducing endothelial adhesion molecule expression. Statins may protect vascular endothelium in hypercholesterolemia by reducing enhanced plasma levels of low-density lipoprotein and decreasing oxidative stress. Herein, we describe increased circulating levels of soluble intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin and total 8-iso-prostaglandin F(2 alpha) (8-iso-PGF(2 alpha)) concentrations, as indexes of endothelial activation and lipid peroxidation, respectively, in 67 hypercholesterolemic patients compared with 32 normocholesterolemic subjects. Significant cholesterol reductions were achieved in hypercholesterolemic patients after 6 months under either simvastatin (40 mg/d) or bezafibrate (800 mg/d) treatment, given according to a randomized double-blind trial. Simvastatin but not bezafibrate simultaneously reduced soluble adhesin and total 8-iso-PGF(2 alpha) concentrations also. Vitamin E supplementation (400 IU/d) further reduced indexes of endothelial activation and lipid peroxidation in simvastatin-treated patients and significantly reduced the above indexes in bezafibrate-treated patients. Changes in circulating soluble adhesion molecule levels were directly correlated with changes in total 8-iso-PGF(2 alpha) concentrations in simvastatin-treated patients also receiving vitamin E supplementation. All together, our data demonstrated that hypercholesterolemia was combined with endothelial activation and lipid peroxidation, which were efficaciously counteracted by simvastatin but not bezafibrate treatment. Thus, a different vascular protection can be achieved by different lipid-lowering treatments.

Prolonged, low dose alpha-tocopherol therapy counteracts intercellular cell adhesion molecule-1 activation.

BACKGROUND: Up-regulation of ICAM-1 at the vascular endothelial level is one of the most important promoters in the slow progression of a healthy vessel to an atherosclerotic one. The current study aimed to evaluate whether low dose of the antioxidant alpha-tocopherol affects the circulating soluble (s) ICAM-1 in healthy subjects. METHODS: Either alpha-tocopherol E (50 I.U./day) or placebo was randomly, double-blindly given to 39 healthy male volunteers (mean age 41.6+/-5.9 years) over a period of 20 weeks. RESULTS: At the baseline, sICAM-1 levels were inversely correlated with alpha-tocopherol concentrations (r=-0.525, p<0.0001). Twenty weeks of alpha-tocopherol supplementation (n=20 subjects) significantly decreased the circulating sICAM-1 levels (from 149.2+/-18.4 to 131.5+/-17.2 microg l(-1), p<0.004) while it increased the alpha-tocopherol concentrations (from 25.8+/-5.0 to 31.2+/-5.7 micromol l(-1), p<0.003). No significant changes in plasma sICAM-1 and alpha-tocopherol levels were observed in placebo-treated subjects (n=19). In actively treated subjects, changes in circulating sICAM-1 were inversely correlated with changes in alpha-tocopherol concentrations (r=-0.597, p=0.005). CONCLUSIONS: Plasma sICAM-1 concentrations are stable in healthy subjects over a period of 20 weeks while they significantly decreased with low dose of alpha-tocopherol. Thus, antioxidant vitamins are likely to counteract with endothelial changes that could potentially trigger the atherogenetic process.