Cardiovascular diseases are a leading cause of mortality and morbidity worldwide, with hypertension being a major risk factor. Numerous studies support the contribution of reactive oxygen and nitrogen species in the pathogenesis of hypertension, as well as other pathologies associated with ischemia/reperfusion. However, the validation of oxidative stress-related biomarkers in these settings is still lacking and novel association of these biomarkers and other biomarkers such as endothelial progenitor cells, endothelial microparticles, and ischemia modified albumin, is just emerging. Oxidative stress has been suggested as a pathogenic factor and therapeutic target in early stages of essential hypertension. Systolic and diastolic blood pressure correlated positively with plasma F2-isoprostane levels and negatively with total antioxidant capacity of plasma in hypertensive and normotensive patients. Cardiac surgery with extracorporeal circulation causes an ischemia/reperfusion event associated with increased lipid peroxidation and protein carbonylation, two biomarkers associated with oxidative damage of cardiac tissue. An enhancement of the antioxidant defense system should contribute to ameliorating functional and structural abnormalities derived from this metabolic impairment. However, data have to be validated with the analysis of the appropriate oxidative stress and/or nitrosative stress biomarkers.

Acute myocardial infarction (AMI) is the leading cause of mortality worldwide. Major advances in the treatment of acute coronary syndromes and myocardial infarction, using cardiologic interventions, such as thrombolysis or percutaneous coronary angioplasty (PCA) have improved the clinical outcome of patients. Nevertheless, as a consequence of these procedures, the ischemic zone is reperfused, giving rise to a lethal reperfusion event accompanied by increased production of reactive oxygen species (oxidative stress). These reactive species attack biomolecules such as lipids, DNA, and proteins enhancing the previously established tissue damage, as well as triggering cell death pathways. Studies on animal models of AMI suggest that lethal reperfusion accounts for up to 50% of the final size of a myocardial infarct, a part of the damage likely to be prevented. Although a number of strategies have been aimed at to ameliorate lethal reperfusion injury, up to date the beneficial effects in clinical settings have been disappointing. The use of antioxidant vitamins could be a suitable strategy with this purpose. In this review, we propose a systematic approach to the molecular basis of the cardioprotective effect of antioxidant vitamins in myocardial ischemia-reperfusion injury that could offer a novel therapeutic opportunity against this oxidative tissue damage.

These data are consistent with the protective effect of high plasma levels of ascorbate against the oxidative challenge caused by reperfusion injury in patients subjected to PCA following an AMI. Further studies are needed to elucidate the mechanism accounting for this beneficial antioxidant effect.

Polyphenols are a structural class of natural and synthetic, organic chemicals characterized mainly by the presence of phenol structural units. Numerous epidemiological and experimental studies have strongly suggested their beneficial effects for human health. This view is supported by their biological activities, which are associated with chemical and biochemical properties, including the ability to act as antioxidants, their antineoplastic effect and the regulation of gene expression in chronic degenerative diseases. These mechanisms of action could account for their preventive and therapeutic uses in human subjects. Moreover, in some therapeutic uses, such as antineoplastic effect, a prooxidant therapeutic action has been suggested. In the diet, numerous compounds could participate in the beneficial properties, and this likely could result in synergistic effects because the whole effect is better than the separately action of each compound. However, the pharmacokinetic and pharmacodynamic properties of these bioactive micronutrients are yet to be further characterized. More research is required to fully establish the therapeutic use of polyphenols against human disease. Based on biological and pharmacological properties of polyphenols both as diet components and supplements, the objective of this work is to show an updated version about the role that polyphenols could play in several chronic diseases such as hypertension, diabetes mellitus, cancer and neurodegenerative disorders.

BackgroundAcute myocardial infarction (AMI) is the leading cause of mortality worldwide. Oxidative stress has been involved in the ischemia-reperfusion injury in AMI. It has been suggested that reperfusion accounts for up to 50% of the final size of a myocardial infarct, a part of the damage likely to be prevented.Therefore, we propose that antioxidant reinforcement through vitamins C and E supplementation should protect against the ischemia-reperfusion damage, thus decreasing infarct size.The PREVEC Trial (Prevention of reperfusion damage associated with percutaneous coronary angioplasty following acute myocardial infarction) seeks to evaluate whether antioxidant vitamins C and E reduce infarct size in patients subjected to percutaneous coronary angioplasty after AMI.Methods/DesignThis is a randomized, 1:1, double-blind, placebo-controlled clinical trial.The study takes place at two centers in Chile: University of Chile Clinical Hospital and San Borja Arriarán Clinical Hospital.The subjects will be 134 adults with acute myocardial infarction with indication for percutaneous coronary angioplasty.This intervention is being performed as a pilot study, involving high-dose vitamin C infusion plus oral administration of vitamin E (Vitamin-treatment group) or placebo (Control group) during the angioplasty procedure. Afterward, the Vitamin-treatment group receives oral doses of vitamins C and E, and the Control group receives placebo for 84 days after coronary angioplasty.Primary outcome is infarct size, assessed by cardiac magnetic resonance (CMR), measured 6 and 84 days after coronary angioplasty.Secondary outcomes are ejection fraction, measured 6 and 84 days after coronary angioplasty with CMR, and biomarkers for oxidative stress, antioxidant status, heart damage, and inflammation, which will be measured at baseline, at the onset of reperfusion, 6 to 8 hours after revascularization, and at hospital discharge.DiscussionThe ischemia-reperfusion event occurring during angioplasty is known to increase myocardial infarct size. The cardioprotective benefits of high doses of vitamin C combined with vitamin E have not been fully explored. The PREVEC Trial seeks to determine the suitability of the therapeutic use of vitamins C and E against the reperfusion damage produced during angioplasty.Patient recruitment opened in February 2013. The trial is scheduled to end in March 2016.Trial registrationISRCTN56034553