Cocoa, blood pressure, and cardiovascular health

New light on changes in the number and function of blood platelets stimulated by cocoa and its products

Hyperactivation of blood platelets, one of the causes of heart attack, and other cardiovascular diseases (CVDs), is influenced by various dietary components, including phenolic compounds from vegetables, fruits, teas, wines, cocoa and its products, including chocolate. The present paper sheds new light on the effect of cocoa and its products, especially dark chocolate, on the number and function of blood platelets, and the anti-platelet activity of their constituent phenolic compounds. A review was performed of papers identified in various electronic databases, including PubMed, Science Direct, Scopus, Web of Knowledge, and Google Scholar, with the aim of determining whether their anti-platelet activity may serve as part of a sweet strategy in countering CVDs. Various studies demonstrate that cocoa consumption, especially in the form of dark chocolate, with a high flavanol concentration, has anti-platelet activity and may play a significant role in cardioprotection; they also note that cocoa consumption may be a good strategy in diminishing cardiovascular risk, including hyperactivation of blood platelets.

Cocoa Consumption Decreases Oxidative Stress, Proinflammatory Mediators and Lipid Peroxidation in Healthy Subjects: A Randomized Placebo-Controlled Dose-Response Clinical Trial

INTRODUCTION

Cocoa flavonoids have been described to reduce the cardiovascular risk. Nevertheless, the involved mechanisms should be clarified and the dose-effect relation has never been evaluated.

AIM

To investigate the dose-dependent effects of cocoa flavonoids on markers of endothelial and platelet activation and oxidative stress.

METHODS

According to a randomized, double-blind, controlled, cross-over design, 20 healthy nonsmokers were assigned to receive either five treatments with daily intake of 10 g cocoa (0, 80, 200, 500 and 800 mg cocoa flavonoids/day) in five periods lasting 1 week each.

RESULTS

Compared with flavonoid-free cocoa control, cocoa reduced sICAM-1 mean values [from 1190.2 to 1123.0; 906.3; 741.7 and 625.6 pg/mL (p = 0.0198 and p = 0.0016, for 500 and 800 mg respectively], sCD40L mean values [from 218.8 to 210.2; 165.5; 134.5 and 128.4 pg/mL (p = 0.023 and p = 0.013, for 500 and 800 mg respectively] and 8-isoprostanes F2 mean values [from 4703.9 to 4670.7; 2000.1; 2098.4 and 2052.3 pg/mL (p = 0.025; p = 0.034 and p = 0.029, for 200, 500 and 800 mg respectively)].

CONCLUSIONS

In our study we observed that short-term cocoa consumption improved proinflammatory mediators, lipid peroxidation and oxidative stress with a significant effect for higher dosages of flavonoids. Our findings suggest cocoa might be a valid tool for dietary intervention in prevention of atherosclerosis.

Cocoa Flavanol Supplementation and the Effect on Insulin Resistance in Females Who Are Overweight or Obese: A Randomized, Placebo-Controlled Trial

There is interest in the impact that dietary interventions can have on preventing the transition from insulin resistance to type 2 diabetes, including a suggestion that the bioactive components of cocoa may enhance fasting insulin sensitivity. However, a role for cocoa flavanols (CF) in reducing insulin resistance in the insulin-stimulated state, an important risk factor for cardiovascular disease, is unresolved. This study investigated whether CF consumption improved whole-body insulin-mediated glucose uptake ('M') in females with overweight/obesity, using a randomized, double-blinded, placebo-controlled, parallel-group design. Thirty-two premenopausal females (19-49 years; 27-35 kg·m-2) with elevated HOMA-IR (HOMA-IR >1.5) supplemented their habitual diet with two servings/day of a high-flavanol cocoa drink (HFC; 609 mg CF/serving; n = 16) or low-flavanol cocoa drink (LFC; 13 mg CF/serving; n = 16) for 4 weeks. Assessment of HOMA-IR and 'M' during a 3-h, 60 mIU insulin·m-2·min-1 euglycemic clamp was performed before and after the intervention. Data are the mean (SD). Changes to HOMA-IR (HFC -0.003 (0.57); LFC -0.0402 (0.86)) and 'M' (HFC 0.99 (7.62); LFC -1.32 (4.88) µmol·kg-1·min-1) after the intervention were not different between groups. Four weeks' consumption of ~1.2 g CF/day did not improve indices of fasting insulin sensitivity or insulin-mediated glucose uptake. A recommendation for dietary supplementation with cocoa flavanols to improve glycemic control is therefore not established.

Structure-Activity Relationship (SAR) of Flavones on Their Anti-Inflammatory Activity in Murine Macrophages in Culture through the NF-κB Pathway and c-Src Kinase Receptor

Flavones benefit human health through their anti-inflammatory activity; however, their structure-activity relationship is unclear. Herein, we selected 15 flavones with the same backbone but different substituents and systematically assessed their anti-inflammatory activities in RAW 264.7 regarding cellular-Src kinase (c-Src) affinity, suppression of IκBα phosphorylation, inhibition of nitric oxide (NO) and inducible nitric oxidase (iNOS) production, and downregulation of genes of proinflammatory cytokines interleukin 6 (IL-6), interleukin 1β (IL-1β), and tumor necrosis factor α (TNF-α). Overall, our results showed that the double bond between C2-C3 and C3'- and C4'-OH promoted anti-inflammatory activity, while C8- and C5'-OH and the methoxy group on C4' attenuated the overall anti-inflammatory and antioxidant activities. The hydroxyl groups at other positions exhibited more complicated functions. The two most effective flavones are 3',4'-dihydroxyflavone and luteolin with inhibitory concentration (IC₅₀) values for inhibiting the LPS-induced nitric oxide level are 9.61 ± 1.36 and 16.90 ± 0.74 μM, respectively. Furthermore, they suppressed the production of iNOS by approximately 90% and inhibited IL-1β and IL-6 by more than 95%. Taken together, our results established a relationship between the flavone structure and anti-inflammatory activity in vitro.

Supplementation with a Cocoa-Carob Blend, Alone or in Combination with Metformin, Attenuates Diabetic Cardiomyopathy, Cardiac Oxidative Stress and Inflammation in Zucker Diabetic Rats

Diabetic cardiomyopathy (DCM) is one of the main causes of mortality among diabetic patients, with oxidative stress and inflammation major contributors to its development. Dietary flavonoids show strong antioxidant and anti-inflammatory activities, although their potential additive outcomes in combination with antidiabetic drugs have been scarcely explored. The present study investigates the cardioprotective effects of a cocoa–carob blend (CCB) diet, rich in flavonoids, alone or in combination with metformin, in the development of DCM. Zucker diabetic fatty rats (ZDF) were fed with a CCB rich-diet or a control diet, with or without metformin for 12 weeks. Glucose homeostasis, cardiac structure and function, and oxidative and inflammatory biomarkers were analysed. CCB improved glucose homeostasis, and mitigated cardiac dysfunction, hypertrophy, and fibrosis in ZDF rats. Mechanistically, CCB counteracted oxidative stress in diabetic hearts by down-regulating NADPH oxidases, reducing reactive oxygen species (ROS) generation and modulating the sirtuin-1 (SIRT1)/ nuclear factor E2-related factor 2 (Nrf2) signalling pathway, overall improving antioxidant defence. Moreover, CCB suppressed inflammatory and fibrotic reactions by inhibiting nuclear factor kappa B (NFκB) and pro-inflammatory and pro-fibrotic cytokines. Noteworthy, several of these effects were further improved in combination with metformin. Our results demonstrate that CCB strongly prevents the cardiac remodelling and dysfunction observed in diabetic animals, highlighting its potential, alone or in adjuvant therapy, for treating DCM.

Antihypertensive Potential of Plant Foods: Research Progress and Prospect of Plant-Derived Angiotensin-Converting Enzyme Inhibition Compounds

Global health concerns are clearly evidenced by cardiovascular disease, kidney damage, and heart attacks. Antihypertensive synthetic drugs, including angiotensin-converting enzyme (ACE) inhibitors, effectively control hypertension but with unpleasant side effects. In recent decades, studies on the role of food-derived compounds have provided a positive contribution to ACE regulation. Here, the research progress of plant food-derived phenolic compounds as ACE inhibitors is reviewed. A survey of bioactive compounds of plant food is presented to broaden the source scope of natural ACE inhibitors. A consecutive understanding of plant-derived ACE inhibitors classification, inhibition mechanism, structure-activity relationship, and bioavailability are scientifically organized. The emerging evidence highlights areas that need further research, including those related to molecular structure, bioaccessibility, and interactions with gut microflora. Future research on such topics may encourage basic research and clinic application to exploit these plant food constituents as novel ACE inhibitors.

Impact of cocoa flavanols on human health

Cocoa is a source of flavanols, and these phenolic compounds exert beneficial effects on health and aging, and reduce the risk of suffering chronic diseases (cardiovascular diseases, metabolic disorders, cancer). An increasing body of evidence has emerged to suggest that cocoa flavanols potentially are important chemopreventive natural agents. This review summarizes human studies from the past two decades, providing data related to the effects derived from cocoa intake on health and disease. Most human studies have reported beneficial effects of cocoa consumption on health and chronic diseases; however, outcomes are not unequivocal. Review of human studies enable to identify different mechanisms of action for cocoa, although they are not fully understood at present. In addition, it remains unclear whether cocoa consumption should be recommended to healthy subjects or to patients and what is the appropriate dosage or duration of cocoa consumption. Elucidation of information regarding these crucial issues could lead to cocoa use as an approach for decreasing the risk of certain chronic diseases, as well as improving health and quality of life.

Chronic flavanol-rich cocoa powder supplementation reduces body fat mass in endurance athletes by modifying the follistatin/myostatin ratio and leptin levels

Flavanols-rich cocoa has positive effects on lipid metabolism and might enhance the performance of athletes through an improvement in their body composition. To test this hypothesis a placebo-controlled intervention study in training endurance athletes who received 5 g of cocoa daily (425 mg of flavanols) for 10 weeks was performed. Dietary intake, body composition, exercise performance and plasma levels of follistatin, myostatin and leptin were measured. Cocoa intake significantly reduced body fat percentage (p = 0.020), specifically in the trunk (p = 0.022), visceral area (p = 0.034) and lower limbs (p = 0.004). The reduction in body fat mass was accompanied by an increase in plasma follistatin and a decrease in leptin, while myostatin levels remained unchanged. The intake of cocoa reduced the percentage of body fat of athletes, without any impact on athletes' performance. The change in fat body composition did not improve athletes' performance.

Preventive effect of cocoa flavanols against glucotoxicity-induced vascular inflammation in the arteria of diabetic rats and on the inflammatory process in TNF-α-stimulated endothelial cells

Hyperglycaemia induces a vascular inflammatory process that is a critical event in cardiovascular disease in type 2 diabetes. Cocoa and its flavanols have been widely investigated for its antioxidant and anti-inflammatory properties, and several clinical and pre-clinical studies support their vascular benefits. However, the effects of cocoa flavanols on vascular inflammation in diabetes remains to be elucidated. Herein, we evaluated the anti-inflammatory effect of a cocoa-rich diet on the aortas of Zucker diabetic fatty (ZDF) rats. Moreover, the potential role of flavanol-derived colonic metabolites to modulate the adhesion and inflammatory processes were also evaluated using TNF-α-stimulated endothelial cells. Results demonstrate that cocoa attenuates the levels of phospho-p65-nuclear factor-kappaB (NF-κB) and the expression of inflammatory factors including intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1) and inducible nitric oxide synthase in the aortas of ZDF rats. Experiments with endothelial cells further confirm that a mix of flavanol-derived colonic metabolites effectively down-regulate the levels of p-p65-NF-κB and the cell adhesion molecules ICAM-1 and VCAM-1, preventing thus the increase of monocyte-endothelial adhesion induced by TNF-α. These novel data provide the first evidence of the relevant role of cocoa and their flavanol-derived metabolites to avoid the development of endothelial inflammation and diabetic complications.

Attenuating Effect of Peruvian Cocoa Populations on the Acute Asthmatic Response in Brown Norway Rats

Cocoa contains bioactive components, which vary according to genetic and environmental factors. The present study aimed to ascertain the anti-allergic properties of native Peruvian cocoa populations ("Blanco de Piura" or BPC, "Amazonas Peru" or APC, "Criollo de Montaña" or CMC, "Chuncho" or CCC, and an ordinary cocoa or OC). To do so, after an initial in vitro approach, an in vivo study focused on the induction of an anaphylactic response associated with allergic asthma in Brown Norway rats was carried out. Based on their polyphenol content, antioxidant activity and in vitro effects, the APC and CMC were selected to be included in the in vivo study. Cocoa diets were tested in a model of allergic asthma in which anaphylactic response was assessed by changes in body temperature, motor activity and body weight. The concentration of specific immunoglobulin E (IgE), mast cell protease and leukotrienes was also quantified in serum and/or bronchoalveolar lavage fluid. CMC and OC populations exhibited a protective effect on the allergic asthma rat model as evidenced by means of a partial protection against anaphylactic response and, above all, in the synthesis of IgE and the release of mast cell protease.

Systemic anti-oxidant capacity is inversely correlated with systolic blood pressure and pulse pressure in children with obesity

BACKGROUND AND AIMS

Oxidative stress leading to endothelial dysfunction is a candidate driver of obesity-related hypertension. We aimed to assess whether the total anti-oxidant capacity (TAC) was associated with blood pressure in children/adolescents with obesity.

METHODS AND RESULTS

One hundred and fifty-two children/adolescents with obesity (79 boys; age 11.9+/-2.5 years) underwent blood drawing for the assessment of TAC, lipids and HOMA-IR. Blood pressure was measured and classified according to the latest American Academy of Pediatrics Guidelines. Serum TAC was measured by a commercial kit (Sigma-Aldrich). The average TAC was 1.11+/-0.4 mMol/Trolox equivalents. Systolic blood pressure was predicted by TAC (B = -5.8, p = 0.003), z-BMI (B = 2.39, p = 0.008), height [cm] (B = 0.38, p < 0.001) and diastolic blood pressure (B = 0.56, p < 0.001). Diastolic blood pressure was predicted by age [years] (B = 0.58, p = 0.001), log-HOMA-IR (B = 3.0, p = 0.002), and systolic blood pressure (B = 0.26, p < 0.001), but not by TAC. The pulse pressure was predicted only by TAC (B = - 6.6, p = 0.002), and height [cm] (B = 0.42, p < 0.001). Overall "elevated blood pressure + hypertension" or hypertension alone were not associated with TAC. However, systolic "elevated blood pressure + hypertension" was associated with TAC (OR = 0.4 [0.1-0.9], p = 0.037), and z-BMI (OR = 2.1 [1.3-3.6], p = 0.004).

CONCLUSION

The systemic anti-oxidant capacity is inversely associated with systolic blood pressure and pulse pressure in children and adolescents with obesity.

Bioavailability and metabolism of selected cocoa bioactive compounds: A comprehensive review

Cocoa beans and their co-products are a rich source of beneficial compounds for health promotion, including polyphenols and methylxanthines. Knowledge of bioavailability and in vivo bioactivity of these phytochemicals is crucial to understand their role and function in human health. Therefore, many studies concerning bioavailability and bioactivity of cocoa bioactive compound have been done in both in vivo animal models and in humans. This critical review comprehensively summarizes the existing knowledge about the bioavailability and the major metabolic pathways of selected cocoa bioactive compounds (i.e. monomeric flavan-3-ols, procyanidins, anthocyanins, flavonols, phenolic acids, N-phenylpropenoyl-L-amino acids, stilbenes, and methylxanthines). The compiled results indicated that many of these compounds undergo extensive metabolism prior to absorption. Different factors have been suggested to influence the bioavailability of polyphenols and methylxanthines among them the role of gut microbiota, structure of these compounds, food matrix and occurrence of other substances were the most often considered. Aforementioned factors decided about the site where these bioactive compounds are digested and absorbed from the alimentary tract, as well as the pathway by which they are metabolized. These factors also determine of the type of transport through the intestine barrier (passive, involving specific enzymes or mediated by specific transporters) and their metabolic path and profile.

Dietary Polyphenols Targeting Arterial Stiffness: Interplay of Contributing Mechanisms and Gut Microbiome-Related Metabolism

Increased arterial stiffness is a degenerative vascular process, progressing with age that leads to a reduced capability of arteries to expand and contract in response to pressure changes. This progressive degeneration mainly affects the extracellular matrix of elastic arteries and causes loss of vascular elasticity. Recent studies point to significant interference of dietary polyphenols with mechanisms involved in the pathophysiology and progression of arterial stiffness. This review summarizes data from epidemiological and interventional studies on the effect of polyphenols on vascular stiffness as an illustration of current research and addresses possible etiological factors targeted by polyphenols, including pathways of vascular functionality, oxidative status, inflammation, glycation, and autophagy. Effects can either be inflicted directly by the dietary polyphenols or indirectly by metabolites originated from the host or microbial metabolic processes. The composition of the gut microbiome, therefore, determines the resulting metabolome and, as a consequence, the observed activity. On the other hand, polyphenols also influence the intestinal microbial composition, and therefore the metabolites available for interaction with relevant targets. As such, targeting the gut microbiome is another potential treatment option for arterial stiffness.

Cardioprotective Mechanisms of Cocoa

Cardiovascular diseases are the main cause of deaths in highly developed countries. Dietetic interventions that involve recommendations for consumption of products with a confirmed health-improving action are an important aspect of prevention of cardiovascular diseases. Cocoa is an alimentary product with significant cardioprotective potential due to its high content of bioactive compounds. The aim of the present study was to review the most recent literature concerning the effectiveness and mechanisms of action of compounds contained in cocoa with regard to selected cardiovascular risk factors and cardiometabolic markers. Study results indicate that cocoa consumption, especially in the form of dark chocolate with high flavonoid content, may be a good strategy to diminish cardiovascular risk due to its beneficial effect on platelet aggregation, decreasing blood pressure, diminishing dyslipidemia, and decreasing blood plasma glucose concentration. Many studies have shown that cocoa-derived flavonoids have antioxidant and anti-inflammatory activity and also play a significant role in preventing insulin resistance. However, in order to completely confirm the potential cardiovascular benefits, it is necessary to conduct larger and longer studies, also with regard to potential dangers associated with long-term consumption of large amounts of flavonoids and determination of a safe and effective dose. Key teaching points Cocoa consumption may be a good strategy in diminishing cardiovascular risk. Beneficial effects on platelet aggregation, blood pressure, dyslipidemia, glycemia, as well as antioxidant and anti-inflammatory activity are observed. There is a need to conduct larger and longer studies to determine a safe and effective dose of cocoa flavonoids.

Cocoa Flavanol Supplementation and Exercise: A Systematic Review

BACKGROUND

Cocoa flavanols (CFs) have antioxidant and anti-inflammatory capacities and can improve vascular function. It has recently been suggested that CF intake may improve exercise performance and recovery. This systematic review aimed to evaluate the literature on the effects of CF intake on exercise performance and recovery and exercise-induced changes in vascular function, cognitive function, oxidative stress, inflammation, and metabolic parameters.

METHODS

Two electronic databases (Pubmed and Web of Science) were searched for studies examining the combination of CF intake and exercise in humans (up to 28 March 2017). Articles were included if the exact amount of CFs was mentioned. The methodological quality and level of bias of the 13 included studies was assessed according to the checklist for randomized controlled trials from the Dutch Cochrane center.

RESULTS

Acute, sub-chronic (2 weeks) and chronic (3 months) CF intake reduced exercise-induced oxidative stress. Evidence on the effect of CF on exercise-induced inflammation and platelet activation was scarce. Acute CF intake reduced and tempered the exercise-induced increase in blood pressure in obese participants. Acute and sub-chronic CF intake altered fat and carbohydrate metabolism during exercise. Acute and sub-chronic CF intake did not have ergogenic effects in athletes, while chronic CF intake improved mitochondrial efficiency in untrained participants. While combining sub-chronic CF intake and exercise training improved cardiovascular risk factors and vascular function, evidence on the synergistic effects of CF and exercise training on oxidative stress, inflammation, and fat and glucose metabolism was lacking.

CONCLUSION

CF intake may improve vascular function, reduce exercise-induced oxidative stress, and alter fat and carbohydrate utilization during exercise, but without affecting exercise performance. There is a strong need for future studies examining the synergetic effect of chronic CF intake and exercise training.

Insulin resistance in ischemic stroke

Insulin resistance often refers to a pathological condition in which cells fail to respond to the normal actions of insulin. Increasing literature has noted a critical role of insulin resistance in the pathogenesis of ischemic stroke. Insulin resistance plays an important role in the pathogenesis of ischemic stroke via enhancing advanced changes of atherosclerosis. A variety of literature indicates that insulin resistance enhances platelet adhesion, activation and aggregation which are conducive to the occurrence of ischemic stroke. Insulin resistance also induces hemodynamic disturbances and contributes to the onset of ischemic stroke. In addition, insulin resistance may augment the role of the modifiable risk factors in ischemic stroke and induce the occurrence of ischemic stroke. Preclinical and clinical studies have supported that improving insulin resistance may be an effective measure to prevent or delay ischemic stroke.

Cocoa, Blood Pressure, and Vascular Function

Cardiovascular disease (CVD) represents the most common cause of death worldwide. The consumption of natural polyphenol-rich foods, and cocoa in particular, has been related to a reduced risk of CVD, including coronary heart disease and stroke. Intervention studies strongly suggest that cocoa exerts a beneficial impact on cardiovascular health, through the reduction of blood pressure (BP), improvement of vascular function, modulation of lipid and glucose metabolism, and reduction of platelet aggregation. These potentially beneficial effects have been shown in healthy subjects as well as in patients with risk factors (arterial hypertension, diabetes, and smoking) or established CVD (coronary heart disease or heart failure). Several potential mechanisms are supposed to be responsible for the positive effect of cocoa; among them activation of nitric oxide (NO) synthase, increased bioavailability of NO as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on BP and vascular function.

Evaluation of the Ability of Polyphenol Extracts of Cocoa and Red Grape to Promote the Antioxidant Response in Yeast Using a Rapid Multiwell Assay

Saccharomyces cerevisiae has been used as a model organism to study the capacity of cocoa and red grape extracts to trigger an antioxidant response. A methodology adapted to microtiter plates has been developed to monitor yeast growth after culture preincubation with food ingredients and exposure to oxidative stress by hydrogen peroxide and menadione. This methodology proved effective in measuring the ability of cocoa and red grape extracts to promote an antioxidant response in yeast, and also the prospect of conducting dose-response studies. Additionally, the method has proven useful to perform studies with mutant strains lacking genes that may be related to the mechanism of action underlying the antioxidant properties. Thus, in a single assay, it is possible to elucidate the sensitivity of strains to oxidative stress, the ability of an ingredient to promote an antioxidant response, and the possible implication of certain genes. Results of assays using strain hst3Δ showed that the antioxidant protection provided by exposure to cocoa and red grape extracts was not present in the strain lacking gene HST3 when H₂ O₂ and menadione were used as oxidizing agents. This effect was previously reported for cocoa extract only, with H₂ O₂ as stressor. Moreover, the results showed that the mutant strain hst3Δ is more resistant to menadione and H₂ O₂ in the absence of preincubation with cocoa and red grape extract, hinting at the possible implication of sirtuin Hst3 in the antioxidant cellular response.

Food and plant bioactives for reducing cardiometabolic disease risk: an evidence based approach

Nutraceuticals active on the main cardiovascular disease risk factors.

Chocolate, Air Pollution and Children's Neuroprotection: What Cognition Tools should be at Hand to Evaluate Interventions?

Millions of children across the world are exposed to multiple sources of indoor and outdoor air pollutants, including high concentrations of fine particulate matter (PM_2.5) and ozone (O₃). The established link between exposure to PM_2.5, brain structural, volumetric and metabolic changes, severe cognitive deficits (1.5-2 SD from average IQ) in APOE 4 heterozygous females with >75 − < 94% BMI percentiles, and the presence of Alzheimer's disease (AD) hallmarks in urban children and young adults necessitates exploration of ways to protect these individuals from the deleterious neural effects of pollution exposure. Emerging research suggests that cocoa interventions may be a viable option for neuroprotection, with evidence suggesting that early cocoa interventions could limit the risk of cognitive and developmental concerns including: endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, and metabolic detrimental brain effects. Currently, however, it is not clear how early we should implement consumption of cocoa to optimize its neuroprotective effects. Moreover, we have yet to identify suitable instruments for evaluating cognitive responses to these interventions in clinically healthy children, teens, and young adults. An approach to guide the selection of cognitive tools should take into account neuropsychological markers of cognitive declines in patients with Alzheimer's neuropathology, the distinct patterns of memory impairment between early and late onset AD, and the key literature associating white matter integrity and poor memory binding performance in cases of asymptomatic familial AD. We highlight potential systemic and neural benefits of cocoa consumption. We also highlight Working Memory Capacity (WMC) and attention control tasks as opened avenues for exploration in the air pollution scenario. Exposures to air pollutants during brain development have serious brain consequences in the short and long term and reliable cognition tools should be at hand to evaluate interventions.

Ex Vivo Treatment with a Polyphenol-Enriched Cocoa Extract Ameliorates Myocardial Infarct and Postischemic Mitochondrial Injury in Normotensive and Hypertensive Rats

Our objective was to determine the effects of a polyphenol-enriched cocoa extract (PCE) on myocardial postischemic alterations in normotensive (Wistar rats, W) and spontaneously hypertensive rats (SHR). Isolated hearts were submitted to 110 min of perfusion or 20 min stabilization, 30 min global ischemia, and 60 min reperfusion (R). Other hearts were treated with PCE at the onset of R. Infarct size, the reduced glutathione (GSH), and the expression of phospho-Akt, P-GSK-3β, and P-eNOS were assessed. In isolated mitochondria, the Ca(2+)-mediated response of mitochondrial permeability transition pore (mPTP), membrane potential (Δψm), and superoxide production were determined. PCE decreased infarct size, partly preserved GSH, increased the P-Akt, P-GSK-3β, and P-eNOS contents, improved mPTP response to Ca(2+), decreased the superoxide production, and restored Δψm. These data show that PCE decreases the cardiac postischemic damage in W rats and SHR and suggest that Akt/GSK-3β/eNOS dependent pathways are involved.

Polyphenol protection and treatment of hypertension

INTRODUCTION

High blood pressure is the major risk factor for cardiovascular diseases and the rising prevalence of human hypertension precedes the trend toward a global epidemic of unhealthy ageing. A focus on lifestyle and dietary interventions minimizes dependency on pharmacological antihypertensive therapies.

REVIEW

Observational studies indicate that the intake of dietary flavonoids is associated with a decreased risk of cardiovascular disease (CVD). The evidence suggests that the dietary intakes of polyphenol-rich foods, herbs and beverages including flavonols, anthocyanidins, proanthocyanidins, flavones, flavanones, isoflavones and flavan-3-ols, improves vascular health, thereby significantly reducing the risk of hypertension and CVD. Consumption is associated with an improvement in endothelial function via vascular eNOS and Akt activation. Increased NO bioavailability improves vasodilation and blood circulation, effects protein kinases, ion channels and phosphodiesterases, counteracting vascular inflammation and LDL oxidative stress. Importantly, some polyphenols also inhibit the activity of matrix metalloproteinases, inhibit angiotensin converting enzyme activity and thereby improving SBP and DSB. We review the improvement of polyphenol intake on blood pressure and endothelial function for the treatment of hypertension, including not only observational but also RCTs and pre-clinical studies.

CONCLUSION

The antihypertensive phytotherapy of polyphenol-rich foods for protection and improving endothelial function with vascular relaxation occurs via the NO-cGMP pathway and ACE inhibition. OPCs stimulate endothelium-dependent vasodilation, suppress vasoconstrictor ET-1 synthesis, activate a laminar shear stress response in endothelial cells and also inhibit the activity of metalloproteinases including ACE lowering blood pressure.