Red wine polyphenols prevent metabolic and cardiovascular alterations associated with obesity in Zucker fatty rats (Fa/Fa)

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Molecular mechanisms of the cardiovascular protective effects of polyphenols

Epidemiological studies have reported a greater reduction in cardiovascular risk and metabolic disorders associated with diets rich in polyphenols. The antioxidant effects of polyphenols are attributed to the regulation of redox enzymes by reducing reactive oxygen species production from mitochondria, NADPH oxidases and uncoupled endothelial NO synthase in addition to also up-regulating multiple antioxidant enzymes. Although data supporting the effects of polyphenols in reducing oxidative stress are promising, several studies have suggested additional mechanisms in the health benefits of polyphenols. Polyphenols from red wine increase endothelial NO production leading to endothelium-dependent relaxation in conditions such as hypertension, stroke or the metabolic syndrome. Numerous molecules contained in fruits and vegetables can activate sirtuins to increase lifespan and silence metabolic and physiological disturbances associated with endothelial NO dysfunction. Although intracellular pathways involved in the endothelial effects of polyphenols are partially described, the molecular targets of these polyphenols are not completely elucidated. We review the novel aspects of polyphenols on several targets that could trigger the health benefits of polyphenols in conditions such as metabolic and cardiovascular disturbances

Estrogen Receptor Alpha as a Key Target of Red Wine Polyphenols Action on the Endothelium

BACKGROUND: A greater reduction in cardiovascular risk and vascular protection associated with diet rich in polyphenols are generally accepted; however, the molecular targets for polyphenols effects remain unknown. Meanwhile evidences in the literature have enlightened, not only structural similarities between estrogens and polyphenols known as phytoestrogens, but also in their vascular effects. We hypothesized that alpha isoform of estrogen receptor (ERalpha) could be involved in the transduction of the vascular benefits of polyphenols. METHODOLOGY/PRINCIPAL FINDINGS: Here, we used ERalpha deficient mice to show that endothelium-dependent vasorelaxation induced either by red wine polyphenol extract, Provinols, or delphinidin, an anthocyanin that possesses similar pharmacological profile, is mediated by ERalpha. Indeed, Provinols, delphinidin and ERalpha agonists, 17-beta-estradiol and PPT, are able to induce endothelial vasodilatation in aorta from ERalpha Wild-Type but not from Knock-Out mice, by activation of nitric oxide (NO) pathway in endothelial cells. Besides, silencing the effects of ERalpha completely prevented the effects of Provinols and delphinidin to activate NO pathway (Src, ERK 1/2, eNOS, caveolin-1) leading to NO production. Furthermore, direct interaction between delphinidin and ERalpha activator site is demonstrated using both binding assay and docking. Most interestingly, the ability of short term oral administration of Provinols to decrease response to serotonin and to enhance sensitivity of the endothelium-dependent relaxation to acetylcholine, associated with concomitant increased NO production and decreased superoxide anions, was completely blunted in ERalpha deficient mice. CONCLUSIONS/SIGNIFICANCE: This study provides evidence that red wine polyphenols, especially delphinidin, exert their endothelial benefits via ERalpha activation. It is a major breakthrough bringing new insights of the potential therapeutic of polyphenols against cardiovascular pathologies

Situation and determinants of the infant and young child feeding (IYCF) indicators in Madagascar: analysis of the 2009 Demographic and Health Survey

Background: Studies evaluating child feeding in Madagascar are scarce despite its importance in child growth during the first two years of life. This study assessed the associations between the WHO infant and young child feeding (IYCF) indicators and stunting and identified determinants of inappropriate child feeding practices.Methods: The most recent Demographic and Health Survey was used including a total of 1956 infants aged 0–23 months. Logistic regressions were performed for the association between IYCF indicators and stunting and for the determination of risk factors for inappropriate feeding practices.Results: The rates of initiation of breastfeeding within one hour after birth (77.2%), continued breastfeeding at one year (99.6%) and timely introduction of solid, semi-solid or soft foods at 6–8 months (88.3%) were high. Exclusive breastfeeding under 6 months (48.8%), attaining minimum dietary diversity (22.2%) and consumption of iron-rich foods (19.6%) were relatively low. Higher length-for-age was associated with achieving minimum dietary diversity (p<0.01). The other indicators assessed (early initiation of breastfeeding, exclusive breastfeeding under 6 months, timely introduction of complementary foods and consumption of iron-rich foods) were not associated with stunting. Infants born to mothers who had first given birth at an age younger than 19 were more likely not to be breastfed within one hour after birth, not to be exclusively breastfed and not to have the recommended dietary diversity. Infants whose mothers had low media exposure were at increased risk of being inappropriately fed. Low household wealth also was associated with higher odds of not meeting the minimum dietary diversity.Conclusions: Despite almost total continued breastfeeding at one year and early initiation of breastfeeding by more than three-quarter of mothers, minimum dietary diversity scores were still low, confirming the need for more effective programs for improving child feeding practices in Madagascar. Improving dietary diversity in children aged 6–23 months may help reduce stunting. The identified risk factors for inappropriate feeding practices could be used in directing future nutrition sensitive interventions.Peer reviewedNutritional Science

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly

Cardiovascular properties of aqueous extract from Tapinanthus dodoneifolius DC Danser

Aqueous extracts of Tapinanthus dodoneifolius DC Danser. (Loranthaceae) (AETD) were investigated for cardiovascular activities on isolated rat aorta and heart. AETD did not affect heart rate but significantly enhanced heart contraction force and relaxation capacity. AETD (0.001-1mg/ml) elicited a dose-dependent relaxation on arteries which was previously contracted with phenylephrine [10-6M] (rat aorta). AETD induces relaxation in endothelium dependent manner. When Indomethacin failed to inhibit AETD vasodilatory activity, in the presence of L-NAME, the vasodilatory activity of AETD was completely abolished. These results suggest a cardiotropic activity without any tachycardia as a side effect for AETD. However, AETD elicited vasodilatory activity which involved NO from endothelium. Key words : Tapinanthus dodoneifolius, endothelium , vasodilator , rat. Afr. J. Trad. Comp. Alt. Med. , 2005, 2 (1): 25-3