A blend of polyphenolic compounds explains the stimulatory effect of red wine on human endothelial NO synthase

Effects of resveratrol on calcium regulation in rats with severe acute pancreatitis

Intracellular calcium overload plays a key role in severe acute pancreatitis. Resveratrol can decrease the severity of pancreatitis; however, the mechanism of action of resveratrol has not been determined. The aim of our study was to examine the relationship between calcium overload and the effects of resveratrol in severe acute pancreatitis. Animals were randomly divided into 3 groups: control group (sham operation), model group (0.1 ml/100 g of 3.5% sodium taurocholate used to induce severe acute pancreatitis), and treated group (treated with resveratrol, 10 mg/kg). In model group, the severity of pancreatitis was aggravated; this was evaluated by pancreatic weight/body weight and lung weight/body weight ratios, serum amylase activities, and pancreatic histopathological scoring; the Ca(2+)-Mg(2+)-ATPase and Ca(2+)-ATPase activities decreased while PLA(2) activity and [Ca(2+)](i) increased gradually with time. Compared to the control group, in the model group, these changes were observed in the pancreatic tissue at the 3 h time point and in the lung tissue at the 6 h time point. Resveratrol ameliorated the changes in the laboratory parameters and significantly reduced the pathological damage in the tissues at the corresponding time points. In conclusion, intracellular calcium overload leads to tissue damage in severe acute pancreatitis, and the beneficial effects of resveratrol appear to be mediated by reducing the intracellular calcium overload; this not only limits pancreatic cellular injury but also secondary lung injury.

Reciprocal regulation of endothelial nitric-oxide synthase and NADPH oxidase by betulinic acid in human endothelial cells

Nitric oxide (NO) produced by endothelial NO synthase (eNOS) is a protective principle in the vasculature. Many cardiovascular diseases are associated with reduced NO bioactivity and eNOS uncoupling due to oxidative stress. Compounds that reverse eNOS uncoupling and increase eNOS expression are of therapeutic interest. Zizyphi Spinosi semen (ZSS) is one of the most widely used traditional Chinese herbs with protective effects on the cardiovascular system. In human umbilical vein endothelial cells (HUVEC) and HUVEC-derived EA.hy 926 cells, an extract of ZSS increased eNOS promoter activity, eNOS mRNA and protein expression, and NO production in a concentration- and time-dependent manner. Major ZSS constituents include saponins, such as jujuboside A and B, and pentacyclic triterpenes, such as betulin and betulinic acid. Jujuboside A, jujuboside B, or betulin had no significant effect on eNOS expression, whereas betulinic acid increased eNOS mRNA and protein expression in HUVEC and EA.hy 926 cells. Interestingly, betulinic acid also attenuated the expression of NADPH oxidase subunits Nox4 and p22phox, thereby reducing oxidative stress and improving eNOS function. Consequently, betulinic acid-treated endothelial cells showed an increased production of bioactive NO (as indicated by a higher efficacy in stimulating cGMP generation in RFL-6 reporter cells). Thus, betulinic acid possesses combined properties of eNOS up-regulation and NADPH oxidase down-regulation. Compounds such as betulinic acid may have a therapeutic potential in cardiovascular disease.

Icariin enhances endothelial nitric-oxide synthase expression on human endothelial cells in vitro

Icariin, a flavonoid isolated from Epimedii herba, is considered to be the major therapeutical constituent of E. herba. The aim of this study was to investigate the possible protective effects and to clarify the mechanism of icariin on endothelial cells in vitro. Incubation of human umbilical vein endothelial cells (HUVEC) derived EA. hy926 cells with icariin(0.1, 1, 10 micromol l(-1)) from 6 h to 72 h, then the production of NO was measured to evaluate the protective effects of icariin. RT-PCR was employed to confirm the mRNA expression of endothelial nitric oxide synthase (eNOS). Western blotting was used to evaluate the protein expression of eNOS. NO production was enhanced in a time- and concentration-dependent manner (P<0.05), which was well matched with the expression of eNOS mRNA (up to 2.4-fold) and protein (up to 2.5-fold) after long-term incubation with icariin in endothelial cells (P<0.05). Moreover, activated NF-kappaB was increased in EA. hy926 cells incubated with icariin for 24 h, in association with an increase in the expression of eNOS gene. In addition to its long-term effects on eNOS expression, icariin also enhanced the production of bioactive NO in the short-term (after a 5 min incubation, P<0.05). In concert with other effects, the protective effects of icariin on endothelial cells may contribute to the cardiovascular protective effects.

Heme oxygenase induction by cyanidin-3-O-β-glucoside in cultured human endothelial cells

The aim of the present research was to investigate the effect of cyanidin-3-O-beta-glucoside (C3G) on heme oxygenase-1 (HO-1), endothelial nitric oxide synthase (eNOS), inducible NOS (iNOS) and dimethylarginine dimethylamino hydrolase-2 (DDAH-2) expression in cultured endothelial cells. Different concentrations (0.00625-250 microM) of C3G were tested in order to investigate possible beneficial and harmful effects of C3G. Our data demonstrated that C3G increased the induction of eNOS and HO-1 in a dose-dependent manner. Higher concentration (62.5-250 microM) also resulted in increase of isoprostane, cGMP and PGE2 levels and in induction of iNOS with consequent oxidative stress. In conclusion, our data evidence that C3G may exert various protective effects against endothelial dysfunction, whereas potentially harmful effects of C3G appear to be limited to concentrations very difficult to be reached in physiological conditions unless there is abundant oral supplementation.

No evidence for modulation of endothelial nitric oxide synthase by the olive oil polyphenol hydroxytyrosol in human endothelial cells

Reduced nitric oxide (NO) availability is associated with the development of atherosclerosis. Upregulation of endothelial nitric oxide synthase (eNOS) activity is pursued as a strategy for the prevention of cardiovascular diseases. The polyphenol hydroxytyrosol (HT) which is present in olive oil and red wine, is regarded to be partly responsible for the beneficial effects associated with olive oil consumption and has shown antiatherogenic activity in vitro and in vivo. To elucidate the underlying molecular mechanisms, we investigated possible effects of HT on the endothelial nitric oxide synthase (eNOS). We used human endothelial cells (EA.hy926) and examined eNOS on three different levels, addressing eNOS promoter transactivation, eNOS enzyme activity and nitric oxide availability. Cells were treated with a broad range of HT concentrations (from 10 nM to 100 microM) and for different incubation times (15 min to 24 h). HT did not exert significant positive effects on eNOS in any of our assay systems. Neither did we find evidence for a possible synergism between the red wine polyphenol resveratrol and HT. We conclude that a direct modulation of eNOS is unlikely to account for the antiatherogenic properties of HT under non-inflammatory conditions.

Activation of endothelial nitric oxide synthase by red wine polyphenols: impact of grape cultivars, growing area and the vinification process

OBJECTIVE

Accumulating data document protective effects of red wine in cardiovascular disease by improved nitric oxide bioavailability. Not all wines, however, seem to be equally effective. The aim of the present study was to elucidate the impact of grape cultivars, growing area and the vinification/fermentation process on the ability of red wine polyphenol extracts to increase human endothelial nitric oxide synthase (eNOS) promotor and enzyme activity.

METHODS

We produced polyphenol extracts from a variety of red wines from all over the world and tested their influence on eNOS promotor activity by a luciferase reporter gene assay. Selected extracts were subjected to the L-arginine-L-citrulline conversion assay to confirm that enhanced eNOS transcription results in enhanced enzyme activity.

RESULTS

We show that polyphenol extracts from wines of specific origin and grape cultivars vary strongly in their individual activity. However, when averaged, the activity could not be attributed to a specific grape cultivar or growing area. Resveratrol alone significantly enhanced eNOS promotor and enzyme activity, although at concentrations higher than those available in effective concentrations of red wine polyphenol extracts. Extracts of grape juice showed activity as well.

CONCLUSIONS

The biological activity of red wines on eNOS transcription depends neither on grape cultivars nor on growing area in general. Resveratrol may be the most promising ingredient in red wine polyphenol extracts, but does not account for the complete effect. A large part of the active components are genuine grape compounds, since extracts of grape juice that did not undergo a fermentation process also showed activity.

Acute Smoking Induces Endothelial Dysfunction in Healthy Smokers. Is This Reversible by Red Wine's Antioxidant Constituents?

OBJECTIVE

Acute smoking causes endothelial dysfunction through impairment of nitric oxide (NO) production, or increased oxidative stress, but the exact mechanism still needs to be elucidated. In healthy non-smokers acute endothelial dysfunction caused by smoking one cigarette was counterbalanced by red wine's antioxidants. The aim of the present study is to investigate whether red wine's antioxidant substances could counteract the acute endothelial dysfunction induced by acute cigarette smoking in healthy smokers as well.

METHODS

Twenty healthy volunteers (12 males) participated in a double-blind, cross-over study, comprised of three study days. All subjects either smoked one cigarette, or smoked and drank 250 ml of red wine, or smoked and drank 250 ml of dealcoholized red wine in each one of the study days. Flow mediated dilatation (FMD) was measured at fast and 30, 60 and 90 minutes after each trial.

RESULTS

Smoking one cigarette induced a significant decrease in FMD (p < 0.001), which remained significant 30 (p < 0.001), and 60 (p = 0.003) minutes after the end of smoking. FMD remained statistically unchanged after consumption of either regular red wine, or dealcoholized red wine together with smoking.

CONCLUSIONS

The observed endothelial dysfunction following smoking of one cigarette was counterbalanced by consumption of either red wine or dealcoholized red wine in healthy smokers. It is possible that acute endothelial dysfunction caused by smoking could be attributed to increased oxidative stress and red wine's antioxidants counteract these acute effects of smoke on endothelium.

Resveratrol—A boon for treating Alzheimer's disease?

Resveratrol, a red wine polyphenol, is known to protect against cardiovascular diseases and cancers, as well as to promote antiaging effects in numerous organisms. It also modulates pathomechanisms of debilitating neurological disorders, such as strokes, ischemia, and Huntington's disease. The role of resveratrol in Alzheimer's disease is still unclear, although some recent studies on red wine bioactive compounds suggest that resveratrol modulates multiple mechanisms of Alzheimer's disease pathology. Emerging literature indicates that mechanisms of aging and Alzheimer's disease are intricately linked and that these mechanisms can be modulated by both calorie restriction regimens and calorie restriction mimetics, the prime mediator of which is the SIRT1 protein, a human homologue of yeast silent information regulator (Sir)-2, and a member of NAD+-dependent histone deacetylases. Calorie restriction regimens and calorie restriction-mimetics trigger sirtuins in a wide variety of organisms, ranging from bacteria to mouse. In a mouse model of Huntington's disease, resveratrol-induced SIRT1 was found to protect neurons against ployQ toxicity and in Wallerian degeneration slow mice, resveratrol was found to protect the degeneration of neurons from axotomy, suggesting that resveratrol may possess therapeutic value to neuronal degeneration. This paper mainly focuses on the role of resveratrol in modulating AD pathomechanisms.

Pomegranate juice protects nitric oxide against oxidative destruction and enhances the biological actions of nitric oxide

Pomegranate juice (PJ), which is a rich source of potent flavonoid antioxidants, was tested for its capacity to protect nitric oxide (NO) against oxidative destruction and enhance the biological actions of NO. Employing chemiluminescence headspace analysis, PJ was found to be a potent inhibitor of superoxide anion-mediated disappearance of NO. PJ was much more potent than Concord grape juice, blueberry juice, red wine, ascorbic acid, and DL-alpha-tocopherol. As little as 3 microl of a 6-fold dilution of PJ, in a reaction volume of 5000 microl, produced a marked antioxidant effect, whereas 300 microl of undiluted blueberry juice or nearly 1000 microl of undiluted Concord grape juice were required to produce similar effects. PJ and other antioxidant-containing products were found to augment the anti-proliferative action of NO (DETA/NO) on vascular smooth muscle cell (rat aorta) proliferation. PJ was much more effective than the other products tested and elicited no effects when tested alone in the absence of added NO. Similarly, neither PJ nor the other products enhanced the anti-proliferative action of alpha-difluoromethylornithine, a stable substance that inhibits cell growth by NO-independent mechanisms. In order to determine whether PJ is capable of increasing the production of NO by vascular endothelial cells, PJ was tested for its capacity to upregulate and/or activate endothelial NO synthase (eNOS) in bovine pulmonary artery endothelial cells. PJ elicited no effects on eNOS protein expression or catalytic activity. Moreover, PJ did not enhance promoter activity in the eNOS gene (COS-7 cells transfected with eNOS). These observations indicate that PJ possesses potent antioxidant activity that results in marked protection of NO against oxidative destruction, thereby resulting in augmentation of the biological actions of NO.

Pharmacological evidence for the participation of NO-cyclic GMP-PKG-K+ channel pathway in the antiallodynic action of resveratrol

The possible participation of the nitric oxide (NO)-cyclic GMP-protein kinase G (PKG)-K+ channels pathway in the antiallodynic action of resveratrol and YC-1 in spinal nerve injured rats was assessed. Ligation of L5/L6 spinal nerves produced a clear-cut tactile allodynia in the rats. Intrathecal administration of resveratrol (100-600 microg) and 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (0.1-2.7 microg, YC-1, a soluble guanylyl cyclase activator) decreased tactile allodynia induced by ligation of L5/L6 spinal nerves. Intrathecal treatment with NG-L-nitro-arginine methyl ester (10-100 microg, L-NAME, a NO synthase inhibitor), 1H-(1,2,4)-oxadiazolo(4,2-a)quinoxalin-1-one (1-10 microg, ODQ, a soluble guanylyl cyclase inhibitor), KT-5823 (5-500 ng, a PKG inhibitor) and iberiotoxin (5-500 ng, a large-conductance Ca2+ -activated K+ channel blocker), but not NG-D-nitro-arginine methyl ester (100 microg, D-NAME, an inactive isomer of L-NAME), glibenclamide (12.5-50 microg, ATP-sensitive K+ channel blocker) or vehicle, significantly diminished resveratrol (300 microg)- and YC-1 (2.7 microg)-induced spinal antiallodynia. These effects were independent of prostaglandin synthesis inhibition as indomethacin did not affect resveratrol-induced antiallodynia. Results suggest that resveratrol and YC-1 could activate the proteins of the NO-cyclic GMP-PKG spinal pathway or large-conductance Ca2+ -activated, but not ATP-sensitive, K+ channels at the spinal cord in order to produce at least part of their antiallodynic effect in this model of neuropathy.

Anthocyanidins decrease endothelin-1 production and increase endothelial nitric oxide synthase in human endothelial cells

Epidemiological and intervention studies correlate anthocyanin-rich beverages and a low incidence of coronary heart diseases. Since endothelin-1 (ET-1) and nitric oxide (NO) produced by endothelial NO synthase (eNOS) are vascular tension regulators secreted by endothelial cells, we studied the influence of two anthocyanidins, namely cyanidin (CY) and delphinidin (DP), on the regulation of ET-1 and eNOS in cultured human umbilical vein endothelial cells (HUVECs). Aglycon anthocyanidin forms, such as CY and DP, may be present in vivo after the first deglycosylation step occurring in the jejunum and in the liver. DP showed a major action compared to CY inducing a significant dose-dependent inhibitory effect on both protein and mRNA levels of ET-1. CY and DP both increased the protein level of eNOS, but DP showed the major effect raising eNOS protein in a dose-dependent manner. To correlate the vasoprotective effect of CY and DP with their antioxidant activity, we analysed also the antioxidant effect of anthocyanidins both in vitro and in HUVECs. In particular, we examined the effect of anthocyanidins on endothelial heme oxygenase-1 (HO-1), an inducible stress protein. In all tests, DP showed a higher antioxidant activity than CY. Finally, the antiproliferative effect induced by DP was detected in HUVECs. DP and CY differ in the number and position of hydroxyl groups in their structure; therefore, the greater biological activity by DP, compared with CY, seems to be due to the presence of the three hydroxyl groups on the B ring in the molecular structure of DP.

Red Wine Induced Modulation of Vascular Function: Separating the Role of Polyphenols, Ethanol, and Urates

By using red wine (RW), dealcoholized red wine (DARW), polyphenols-stripped red wine (PSRW), ethanol-water solution (ET), and water (W), the role of wine polyphenols, ethanol, and urate on vascular function was examined in humans (n = 9 per beverage) and on isolated rat aortic rings (n = 9). Healthy males randomly consumed each beverage in a cross-over design. Plasma ethanol, catechin, and urate concentrations were measured before and 30, 60 and 120 minutes after beverage intake. Endothelial function was assessed before and 60 minutes after beverage consumption by normalized flow-mediated dilation (FMD). RW and DARW induced similar vasodilatation in the isolated vessels whereas PSRW, ET, and W did not. All ethanol-containing beverages induced similar basal vasodilatation of brachial artery. Only intake of RW resulted in enhancement of endothelial response, despite similar plasma catechin concentration after DARW. The borderline effect of RW on FMD (P = 0.0531) became significant after FMD normalization (P = 0.0043) that neutralized blunting effect of ethanol-induced basal vasodilatation. Effects of PSRW and ET did not differ although plasma urate increased after PSRW and not after ET, indicating lack of urate influence on endothelial response. Acute vascular effects of RW, mediated by polyphenols, cannot be predicted by plasma catechin concentration only.

Consumption of Bing sweet cherries lowers circulating concentrations of inflammation markers in healthy men and women

The purpose of this study was to determine the effects of consuming sweet cherries on plasma lipids and markers of inflammation in healthy humans. Healthy men and women (n = 18) supplemented their diets with Bing sweet cherries (280 g/d) for 28 d. After a 12-h fast, blood samples were taken before the start of cherry consumption (study d 0 and 7), 14 and 28 d after the start of cherry supplementation (study d 21 and 35), and 28 d after the discontinuation (study d 64) of cherry consumption. After cherries were consumed for 28 d, circulating concentrations of C-reactive protein (CRP), regulated upon activation, normal T-cell expressed, and secreted (RANTES), and NO decreased by 25 (P < 0.05), 21 (P < 0.05), and 18% (P = 0.07) respectively. After the discontinuation of cherry consumption for 28 d (d 64), concentrations of RANTES continued to decrease (P = 0.001), whereas those of CRP and NO did not differ from either d 7 (pre-cherries) or d 35 (post-cherries). Plasma concentrations of IL-6 and its soluble receptor, intercellular adhesion molecule-1, and tissue inhibitor of metalloproteinases-2 did not change during the study. Cherry consumption did not affect the plasma concentrations of total-, HDL-, LDL-, and VLDL- cholesterol, triglycerides, subfractions of HDL, LDL, VLDL, and their particle sizes and numbers. It also did not affect fasting blood glucose or insulin concentrations or a number of other chemical and hematological variables. Results of the present study suggest a selective modulatory effect of sweet cherries on CRP, NO, and RANTES. Such anti-inflammatory effects may be beneficial for the management and prevention of inflammatory diseases.

A central role of eNOS in the protective effect of wine against metabolic syndrome

The positive health effects derived from moderate wine consumption are pleiotropic. They appear as improvements in cardiovascular risk factors such as plasma lipids, haemostatic mechanisms, endothelial function and antioxidant defences. The active principles would be ethanol and mainly polyphenols. Results from our and other laboratories support the unifying hypothesis that the improvements in risk factors after red wine consumption are mediated by endothelial nitric oxide synthase (eNOS). Many genes are involved, but the participation of eNOS would be a constant feature. The metabolic syndrome is a cluster of metabolic risk factors associated with high risk of cardiovascular disease (CVD). The National Cholesterol Education Programmmes Adult Treatment Panel III (NCEPATP III) clinical definition of the metabolic syndrome requires the presence of at least three risk factors, from among abdominal obesity, high plasma triacylglycerols, low plasma HDL, high blood pressure and high fasting plasma glucose. The molecular mechanisms responsible for the metabolic syndrome are not known. Since metabolic syndrome apparently affects 10-30% of the population in the world, research on its pathogenesis and control is needed. The recent finding that eNOS knockout mice present a cluster of cardiovascular risk factors comparable to those of the metabolic syndrome suggests that defects in eNOS function may cause human metabolic syndrome. These mice are hypertensive, insulin resistant and dyslipidemic. Further support for a pathogenic role of eNOS comes from the finding in humans that eNOS polymorphisms associate with insulin resistance and diabetes, with hypertension, with inflammatory and oxidative stress markers and with albuminuria. So, the data sustain the hypothesis that eNOS enhancement should reduce metabolic syndrome incidence and its consequences. Therefore red wine, since it enhances eNOS function, should be considered as a potential tool for the control of metabolic syndrome. This hypothesis is supported by epidemiological observations and needs experimental validation in human intervention studies.

Stilbene Derivatives from Pholidota chinensis and Their Anti-inflammatory Activity

Ethyl acetate extract of Pholidota chinensis L. showed strong NO production inhibitory activity in murine macrophage-like cell line, RAW 264.7, which was activated by a lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). Fractionation of the active extract led to the isolation of two new stilbene derivatives, 2,3'-dihydroxy-5-methoxy-3,4-methylenedioxydihydrostilbene (Pholidotol A) and 2-hydroxy-5-methoxy-3,4,3',4'-dimethylenedioxydihydrostilbene (Pholidotol B) together with six known stilbene derivatives. Pholidotols A both B and inhibited Nitric oxide (NO) production with an IC(50) value at 24.3 and 17.1 microM, respectively.

Cinnamaldehyde Induces Endothelium-Dependent and -Independent Vasorelaxant Action on Isolated Rat Aorta

The vasorelaxant effect of cinnamaldehyde, one of the major oil components in Cinnamomi Cortex, was studied using isolated rat aorta. Cinnamaldehyde at final concentrations of 1 microM to 1 mM showed dose-dependent relaxation of the rat aorta contracted by treatment with prostaglandin F2alpha, norepinephrine or KCl. In addition, cinnamaldehyde relaxed prostaglandin F2alpha-precontracted aortic rings with endothelium and without endothelium, with the latter being significantly less sensitive than the former. Relaxation induced by cinnamaldehyde with endothelium was significantly inhibited by NG-nitro-L-arginine methyl ester (L-NAME), while nonselective cyclooxygenase inhibitor (indomethacin), beta-adrenergic receptor blocker (propranolol), an inhibitor of phosphodiesterase (theophylline), a delayed rectifier K+ channel blocker (tetraethyl ammonium chloride), or an ATP-sensitive K+ channel blocker (glibenclamide) did not reduce the relaxation induced by cinnamaldehyde with endothelium treated by L-NAME. Conversely, aorta pretreatment with L-NAME and theophylline increased the relaxation by cinnamaldehyde significantly compared to aorta pretreatment with only L-NAME. Furthermore, cinnamaldehyde significantly inhibited Ca2+-induced contraction. These results suggested that the vasorelaxant effects of cinnamaldehyde were derived from both endothelium-dependent and -independent effects. Endothelium-dependent relaxation is affected by nitric oxide, and one of the mechanisms of endothelium-independent relaxation is thought to be influenced by the blocking of Ca2+ channels.

Epicatechin protects endothelial cells against oxidized LDL and maintains NO synthase

Intake of flavanol-rich food or beverages was previously shown to ameliorate endothelial function and to enhance bioactivity of nitric oxide with individuals at risk for cardiovascular disease. Here, we examined whether the major dietary flavanol, (-)-epicatechin, counteracts the action of oxidized LDL on endothelial cells, an action considered pivotal for endothelial dysfunction in the pathogenesis of atherosclerosis. Oxidation by myeloperoxidase plus nitrite rendered human LDL cytotoxic towards endothelial cells, more so than oxidation by Cu2+. Oxidized LDL also caused a marked loss of endothelial NO synthase protein which did not occur in the presence of a proteasome inhibitor, lactacystin. Both actions of oxidized LDL, which were not evoked by native LDL, were effectively counteracted by (-)-epicatechin. We conclude that dietary flavanols contribute to protection of the integrity of endothelial cells not only by scavenging free radicals but also by maintaining endothelial NO synthase.

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.