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Studies have linked the development of sarcopenia to reductions in capillary vessel network density and suggest that such changes may partly account for the loss of skeletal muscle (SkM) mass and function. Thus, the interest in identifying and evaluating safe and effective candidate compounds that can stimulate angiogenesis. We previously reported on the capacity of (+)-epicatechin (+Epi) to reverse SkM atrophy and loss of function in aged rats. We also reported on the apparent angiogenic effect of +Epi in mouse brain cortex. However, no studies have evaluated the angiogenic potential of +Epi in SkM. Using 23 month old male rats, we evaluated the angiogenic effect of 8 weeks of 1 mg/kg/day oral treatment of +Epi on SkM (gastrocnemius). To identify underlying mechanisms, we evaluated the PI3K/eNOS pathway, as well as the expression of the angiogenic factors HIF1-α, VEGF and VEGFR2. Results demonstrate that + Epi stimulates increases in protein levels for HIF1-α (∼35%), VEGF (∼40%), VEGFR2 (∼25%), as well as CD31 (capillaries, ∼25%). Such effects were linked with the activation (phosphorylation) of PI3K (∼30%), eNOS (∼90%), VEGFR2 at T951 (∼90%) and T996 amino acid sites (∼110%). +Epi also stimulated increased synthesis of phosphatidylinositol trisphosphate (∼30%) and tetrahydrobiopterine (∼90%), as well as of nitric oxide (∼140% in gastrocnemius and ∼70% in plasma) and cyclic guanosine monophosphate (∼90%) in gastrocnemius and in plasma (∼40%). In summary, in aged rats oral treatment with +Epi stimulates SkM angiogenesis and such actions may partly account for the reversal of the deleterious effects of sarcopenia.

Nonalcoholic fatty liver disease (NAFLD) is characterized by a spectrum of diseases, ranging from simple steatosis to hepatocellular carcinoma. The main factors for NAFLD are closely related to obesity, insulin resistance, intestinal microbiota alterations, hyperinsulinism, low-grade systemic inflammation, nitroxidative stress, lipid peroxidation, and mitochondrial dysfunction. Currently, the treatment of NAFLD is based on diet and exercise because, to date, there is no specific pharmacological agent, already approved, that raises the need for new therapeutic strategies. Nutraceuticals, such as polyphenols, have potential beneficial effects for health. In this article, the beneficial effects of epigallocatechin-3-gallate (EGCG) and (−)-epicatechin (EC) are discussed. EGCG is the main catechin in green tea, which has shown in various studies its potential effect preventing and treating NAFLD since it has shown antihyperlipidemic, anti-inflammatory, antifibrotic, antioxidant, and improvement of liver lipid metabolism. However, it has been found that excessive consumption may cause hepatotoxicity. EC is widely distributed in nature (fruits and vegetables). This flavanol has shown many beneficial effects, including antihypertensive, anti-inflammatory, anti-hyperglycemic, antithrombotic, and antifibrotic properties. It increases mitochondrial biogenesis, and it also has effects on the regulation of synthesis and metabolism of lipids. This flavanol is a nontoxic substance; it has been classified by the United States Food and Drug Administration as harmless. The EC-induced effects can be useful for the prevention and/or treatment of NAFLD.

La obesidad se caracteriza por un aumento generalizado de tejido adiposo, alta producción de adipocitocinas y presencia de estrés oxidativo sistémico. El objetivo de este estudio fue evaluar los cambios generados en el estrés oxidativo y los parámetros antropométricos en sujetos obesos por la prescripción de una dieta hipocalórica en combinación con ejercicio aeróbico moderado y suplementación con antioxidantes.

More than half of all global deaths in 2010 were related to non-communicable diseases, including obesity, cancers, diabetes, and cardiovascular illnesses. It has been suggested that the alarming increase in the incidence of cardiovascular disease is the epidemiologic result of a nutrition transition characterized by dietary patterns featuring an increase in the intake of total fat, cholesterol, sugars, and other refined carbohydrates, concomitant with low consumption of polyunsaturated fatty acids and fiber. Although traditional dietary approaches have proven successful as part of the treatment for obesity and cardiometabolic derangements within clinical trial scenarios, they lack effectiveness in the long term, mainly due to poor compliance. Research has thus turned its attention to nutraceutics, nutrients that have the ability to modulate physiological and pathophysiological molecular mechanisms, thus resulting in favorable health outcomes. Polyphenols have been considered as among the bioactive molecules as they are thought to yield beneficial effects by exerting antioxidant activity; however, there are other - and even more robust - metabolic pathways through which polyphenols enhance cardiovascular health, such as via promoting vasodilatory, anti-atherogenic, antithrombotic, and anti-inflammatory effects. No standard dose has yet been determined, as the effects greatly vary among polyphenols and food sources; thus, there is an imperative need to generate more evidence in order to support dietary recommendations aimed at the prevention and therapeutics of obesity and its associated cardiometabolic diseases.

The consumption of moderate amounts of cocoa products has been associated with reductions in the incidence of cardiovascular diseases. In animal studies, the flavanol (-)-epicatechin (Epi) yields cardioprotection. The effects may be partly due to its capacity to stimulate endothelial nitric oxide synthase (eNOS). The sustained activation of eNOS, as observed with exercise, can serve as a trigger of muscle angiogenesis via the activation of vascular endothelial growth factor (VEGF)–related events. Experiments were pursued to examine the potential of Epi to stimulate myocardial angiogenesis and determine the effects that its combined use with exercise (Ex) may trigger. Hearts obtained from a previous study were used for this purpose. Animals received 1 mgkg of Epi or water (vehicle) via oral gavage (twice daily). Epi andor Ex (by treadmill) was provided for 15 days. Results indicate that Ex or Epi significantly stimulate myocardial angiogenesis by ∼30 above control levels. The use of Epi-Ex lead to further significant increases (to ∼50). Effects were associated with increases in protein levels andor activation of canonical angiogenesis pathway associated events (HIF1a, VEGF, VEGFR2, PI3K, PDK, AKT, eNOS, NO, cGMP, MMP-2-9, Src-1, and CD31). Thus, the use of Epi may represent a safe and novel means to stimulate myocardial angiogenesis.

Caveolins are a family of integral membrane proteins implicated in various cell functions, including the organization and inactivation of signaling molecules of G protein-coupled receptors. We tested the ability of human caveolin scaffolding peptide-1 (CSP-1) to regulate norepinephrine- (NE) or histamine (HIS)-induced increases on intracellular calcium concentrations ([Ca2+]i). In cultured rat vascular smooth muscle cells (VSMC), CSP-1 inhibited in a concentration-dependent manner NE- and HIS-induced increases in [Ca2+]i. This effect can be explained by the fact that CSP-1 inhibited a common signaling pathway. We tested the ability of this peptide to decrease the activation of PLC-β3 and MAPK. CSP-1 inhibited the expression of the activated form of both enzymes, suggesting a direct effect of the peptide on the signaling cascade. CSP-1 readily enters VSMC in culture, as observed when FITC-conjugated CPS-1 is added to cell culture media. Taken together, these data suggest that CSP-1 blocks the effects of NE and HIS on [Ca2+]iof VSMC by inhibiting the activation of PLC-β3 and MAPK.

Gonadal steroid hormones influence vascular tone and the development of hypertension. There are sex differences in the incidence of cardiovascular diseases, and great attention has been placed on the study of estrogen cardiovascular effects. However, there are only a few reports on the effects of testosterone on the vasculature. It is commonly accepted that the mechanism of the action of steroid hormones on target tissues is mediated through the binding of hormones to cytoplasmic or nuclear receptors. However, some studies indicate that steroid action can be extremely rapid and therefore unlikely to be through a genomic mechanism. The purpose of this study was to assess the effect of intravascularly confined testosterone on an isolated rat heart to demonstrate acute and possibly nongenomic effects of the steroid. Our results show that testosterone blocked the adenosine vasodilator effect and increased vascular resistance, even when its presence was restricted to the coronary vascular lumen. These effects were exerted rapidly and possibly through nongenomic mechanisms.

Age-related muscle decline, when associated with obesity, leads to adverse outcomes with increased risks for falling, loss of independence, disability and risk of premature mortality. The aim of this study was to assess the potential beneficial effects of flavonoids in improving the age-/high-fat-diet-induced decrease in physical activity/capacity related to the onset of skeletal muscle decline. The effects of the administration of a cocoa beverage enriched with flavanols or pure (−)-epicatechin for 5 wk in a model of physical activity decline induced by the ingestion of a high-fat diet (60% fat) in middle-age mice were evaluated. The results showed that both products, the cocoa beverage enriched with flavanols and pure (−)-epicatechin, improved physical performance evaluated with the hang-wire, inverted-screen, and weight-lifting tests and dynamometry compared with the performance of the controls. The beverage and (−)-epicatechin increased the follistatin/myostatin ratio and increased the expression of myocyte enhancer factor 2A (MEF2A), suggesting an effect on molecular modulators of growth differentiation. Furthermore, the beverage and (−)-epicatechin decreased the expression of O-type fork-head transcription factor (FOXO1A) and muscle ring finger 1 (MURF1) markers of the skeletal muscle ubiquitin-proteasome degradation pathway.