A Critical Review on Vasoactive Nutrients for the Management of Endothelial Dysfunction and Arterial Stiffness in Individuals under Cardiovascular Risk

Pathophysiological conditions such as endothelial dysfunction and arterial stiffness, characterized by low nitric oxide bioavailability, deficient endothelium-dependent vasodilation and heart effort, predispose individuals to atherosclerotic lesions and cardiac events. Nitrate (NO₃^-), L-arginine, L-citrulline and potassium (K⁺) can mitigate arterial dysfunction and stiffness by intensifying NO bioavailability. Dietary compounds such as L-arginine, L-citrulline, NO₃^- and K⁺ exert vasoactive effects as demonstrated in clinical interventions by noninvasive flow-mediated vasodilation (FMD) and pulse-wave velocity (PWV) prognostic techniques. Daily L-arginine intakes ranging from 4.5 to 21 g lead to increased FMD and reduced PWV responses. Isolated L-citrulline intake of at least 5.6 g has a better effect compared to watermelon extract, which is only effective on endothelial function when supplemented for longer than 6 weeks and contains at least 6 g of L-citrulline. NO₃^- supplementation employing beetroot at doses greater than 370 mg promotes hemodynamic effects through the NO₃^--NO2-/NO pathway, a well-documented effect. A potassium intake of 1.5 g/day can restore endothelial function and arterial mobility, where decreased vascular tone takes place via ATPase pump/hyperpolarization and natriuresis, leading to muscle relaxation and NO release. These dietary interventions, alone or synergically, can ameliorate endothelial dysfunction and should be considered as adjuvant therapies in cardiovascular diseases.

Betanin as a multipath oxidative stress and inflammation modulator: a beetroot pigment with protective effects on cardiovascular disease pathogenesis

Oxidative stress is a common physiopathological condition enrolled in risk factors for cardiovascular diseases. Individuals in such a redox imbalance status present endothelial dysfunctions and inflammation, reaching the onset of heart disease. Phytochemicals are able to attenuate the main mechanisms of oxidative stress and inflammation and should be considered as supportive therapies to manage risk factors for cardiovascular diseases. Beetroot (Beta vulgaris L.) is a rich source of bioactive compounds, including betanin (betanidin-5-O-β-glucoside), a pigment displaying the potential to alleviate oxidative stress and inflammantion, as previously demonstrated in preclinical trials. Betanin resists gastrointestinal digestion, is absorbed by the epithelial cells of intestinal mucosa and reaches the plasma in its active form. Betanin displays free-radical scavenger ability through hydrogen or electron donation, preserving lipid structures and LDL particles while inducing the transcription of antioxidant genes through the nuclear factor erythroid-2-related factor 2 and, simultaneously, suppressing the pro-inflammatory nuclear factor kappa-B pathways. This review discusses the anti-radical and gene regulatory cardioprotective activities of betanin in the pathophysiology of endothelial damage and atherogenesis, the main conditions for cardiovascular disease. In addition, betanin influences on these multipath cellular signals and aiding in reducing cardiovascular disorders is proposed.

Short-Term Betanin Intake Reduces Oxidative Stress in Wistar Rats

Oxidative stress is a common condition described in risk factors for cardiovascular disease. Betanin, a bioactive pigment from red beetroot demonstrates anti-inflammatory and antioxidant properties. The main aim of this study was to evaluate the short-term intake of betanin against oxidative stress in a rodent model, a common condition described in several risk factors for cardiovascular disease. Oxidative stress was induced in Wistar rats by a hyperlipidemic diet for 60 days, followed by betanin administration (20 mg·kg⁻¹) through oral gavage for 20 days. Plasma biochemical parameters and antioxidant enzyme activities were evaluated. Lipid peroxidation and histopathological changes were determined in the liver. The hyperlipidemic diet caused hyperglycemia, hyperinsulinemia, insulin resistance, and increases in alanine transaminase and aspartate transaminase levels. Oxidative stress status was confirmed by reduction of antioxidant enzyme activities, increased lipid peroxidation, and liver damage. Purified betanin regulated glucose levels, insulin, and insulin resistance. Hepatic damage was reversed as evidenced by the reduction in alanine transaminase and aspartate transaminase levels and confirmed by histological analyses. Betanin reduced hepatic malondialdehyde and increased superoxide dismutase, catalase, and glutathione peroxidase activities. Short-term betanin intake modulated biochemical parameters, reversed hepatic tissue damage, and attenuated oxidative stress in Wistar rats.

Betanin, a Natural Food Additive: Stability, Bioavailability, Antioxidant and Preservative Ability Assessments

Betanin is the only betalain approved for use in food and pharmaceutical products as a natural red colorant. However, the antioxidant power and health-promoting properties of this pigment have been disregarded, perhaps due to the difficulty in obtaining a stable chemical compound, which impairs its absorption and metabolism evaluation. Herein, betanin was purified by semi-preparative HPLC-LC/MS and identified by LC-ESI(+)-MS/MS as the pseudomolecular ion m/z 551.16. Betanin showed significant stability up to -30 °C and mild stability at chilling temperature. The stability and antioxidant ability of this compound were assessed during a human digestion simulation and ex vivo colon fermentation. Half of the betanin amount was recovered in the small intestine digestive fluid and no traces were found after colon fermentation. Betanin high antioxidant ability was retained even after simulated small intestine digestion. Betanin, besides displaying an inherent colorant capacity, was equally effective as a natural antioxidant displaying peroxy-radical scavenger ability in pork meat. Betanin should be considered a multi-functional molecule able to confer an attractive color to frozen or refrigerated foods, but with the capacity to avoid lipid oxidation, thereby preserving food quality. Long-term supplementation by beetroot, a rich source of betanin, should be stimulated to protect organisms against oxidative stress.

Polyphenols from Root, Tubercles and Grains Cropped in Brazil: Chemical and Nutritional Characterization and Their Effects on Human Health and Diseases

Throughout evolution, plants have developed the ability to produce secondary phenolic metabolites, which are important for their interactions with the environment, reproductive strategies and defense mechanisms. These (poly)phenolic compounds are a heterogeneous group of natural antioxidants found in vegetables, cereals and leguminous that exert beneficial and protective actions on human health, playing roles such as enzymatic reaction inhibitors and cofactors, toxic chemicals scavengers and biochemical reaction substrates, increasing the absorption of essential nutrients and selectively inhibiting deleterious intestinal bacteria. Polyphenols present in some commodity grains, such as soy and cocoa beans, as well as in other vegetables considered security foods for developing countries, including cassava, taro and beetroot, all of them cropped in Brazil, have been identified and quantified in order to point out their bioavailability and the adequate dietary intake to promote health. The effects of the flavonoid and non-flavonoid compounds present in these vegetables, their metabolism and their effects on preventing chronic and degenerative disorders like cancers, diabetes, osteoporosis, cardiovascular and neurological diseases are herein discussed based on recent epidemiological studies.