Valorización de lías de vino como ingredientes antihipertensivos

Resumen Algunos coproductos vitivinícolas se han utilizado para obtener extractos enriquecidos en (poli)fenoles con efectos antihipertensivos. Sin embargo, aún se desconoce si las lías de vino (LV) contienen compuestos antihipertensivos. Este estudio se centró en estudiar si las LV podría ser fuente de estos compuestos. Se evaluó la actividad antihipertensiva de cinco LV (fracción líquida, 5 mL/kg) en ratas hipertensas (SHR). Una de las LV mostró un fuerte efecto antihipertensivo, que se asoció con su alto contenido en flavanoles y antocianinas. La reducción del estrés oxidativo y mejora del estado redox y disfunción endotelial fueron algunos mecanismos involucrados en su bioactividad. Además, las LV se sometieron a extracción asistida por enzimas (Flavourzyme®), lo cual solubilizó compuestos fenólicos (57.20%) inicialmente no solubles. Ácido gálico, catequina y malvidina-3-glucósido fueron los principales (poli)fenoles de este hidrolizado. Además, el hidrolizado mostró una mayor actividad inhibitoria de la enzima convertidora de angiotensina, antioxidante y antihipertensiva que las LV. Los péptidos FKTTDQQTRTTVA, NPKLVTIV, TVTNPARIA, LDSPSEGRAPG y LDSPSEGRAPGAD, identificados en el hidrolizado, exhibieron actividad antihipertensiva en SHR (10 mg/kg). LV son una buena fuente de compuestos antihipertensivos con potencial para usarse como nutracéuticos o ingredientes funcionales. Esto permitiría la valorización de las mismas y contribuiría a la economía circular de la industria vitivinícola

Antioxidant properties of polyphenol-rich cocoa products industrially processed

Fermentation and roasting are the main causes of polyphenol degradation during the process for obtaining cocoa products. In the present study, a process for obtaining polyphenol-rich cocoa products on an industrial scale is described. The process avoids the fermentation and roasting steps and includes a step for the inactivation of the enzyme Polyphenol Oxidase (PPO), which helps preserve the polyphenol content present in the raw cocoa bean. In addition, our study evaluates the antioxidant capacity and characterizes the flavonoid profile of the polyphenol-rich cocoa products obtained from the natural polyphenolrich cocoa cake. Using different protocols, we have obtained three cocoa extracts with high polyphenol content, namely extracts A (167 mg/g), B (374 mg/g) and C (787 mg/g). The scavenging capacity of the extracts was measured as their ability to bleach the stable radicals DPPH and ABTS + while their antioxidant effect was evaluated with the FRAP assay. The results for A, B and C in the DPPH test expressed as Trolox equivalent (lmol)/mg dry weight of extract were 0.2, 1.4 and 3.0, respectively; in the ABTS test the results were 1.0, 4.7 and 9.8. The antioxidant capacity expressed as ascorbic acid equivalent (lmol)/mg dry weight of each product were 17.2, 76.1 and 207.7, respectively. The scavenging properties of cocoa powder against the superoxide anion, H2O2, HClO, and peroxynitrite were also determined. The IC50 (lg/mL) values in the hypoxanthine/xanthine oxidase test were 77.5, 12.3 and 10.3, for A, B and C, respectively, while as an HOCl scavenger the IC50 (lg/mL) values were 225.4, 73.2 and 21.5. As a peroxynitrite anion scavenger, only extract C had a relevant effect, with IC50 (lg/mL) values of 76.1 or 110.0 in the absence or presence of bicarbonate. None of the extracts tested showed activity in the hydrogen peroxide test, but B and C significantly increased the deoxyribose degradation in the absence of ascorbate. Likewise, none of the extracts inhibited the ferrous or copper chelating activity at 100 lg/mL, but they inhibited the lipid peroxidation in brain homogenates and human plasma through non-enzymatic generation systems, with extract C giving the best IC50 (lg/mL) values: 17.4 and 8.1 against lipid peroxidation in brain homogenates and human plasma, respectively. In conclusion, if the extractive protocol is well characterized, defined and optimized, cocoa could constitute a source of polyphenols for enriching foods, nutraceuticals and alimentary supplements.Facultad de Ciencias Médicas (FCM

Alimentos de temporada, ritmos y sincronización biológica

III Congreso de Alimentación, Nutrición y Dietética. Combinar la nutrición comunitaria y personalizada: nuevos retos

Chrononutrition and Polyphenols: Roles and Diseases

Biological rhythms can influence the activity of bioactive compounds, and at the same time, the intake of these compounds can modulate biological rhythms. In this context, chrononutrition has appeared as a research field centered on the study of the interactions among biological rhythms, nutrition, and metabolism. This review summarizes the role of phenolic compounds in the modulation of biological rhythms, focusing on their effects in the treatment or prevention of chronic diseases. Heterotrophs are able to sense chemical cues mediated by phytochemicals such as phenolic compounds, promoting their adaptation to environmental conditions. This is called xenohormesis. Hence, the consumption of fruits and vegetables rich in phenolic compounds exerts several health benefits, mainly attributed to the product of their metabolism. However, the profile of phenolic compounds present in plants differs among species and is highly variable depending on agricultural and technological factors. In this sense, the seasonal consumption of polyphenol-rich fruits could induce important changes in the regulation of physiology and metabolism due to the particular phenolic profile that the fruits contain. This fact highlights the need for studies that evaluate the impact of these specific phenolic profiles on health to establish more accurate dietary recommendations.España MINISTERIO DE ECONOMÍA, INDUSTRIA Y COMPETITIVIDAD (AGL2016-77105-R

Antioxidant properties of polyphenol-rich cocoa products industrially processed

Fermentation and roasting are the main causes of polyphenol degradation during the process for obtaining cocoa products. In the present study, a process for obtaining polyphenol-rich cocoa products on an industrial scale is described. The process avoids the fermentation and roasting steps and includes a step for the inactivation of the enzyme Polyphenol Oxidase (PPO), which helps preserve the polyphenol content present in the raw cocoa bean. In addition, our study evaluates the antioxidant capacity and characterizes the flavonoid profile of the polyphenol-rich cocoa products obtained from the natural polyphenolrich cocoa cake. Using different protocols, we have obtained three cocoa extracts with high polyphenol content, namely extracts A (167 mg/g), B (374 mg/g) and C (787 mg/g). The scavenging capacity of the extracts was measured as their ability to bleach the stable radicals DPPH and ABTS + while their antioxidant effect was evaluated with the FRAP assay. The results for A, B and C in the DPPH test expressed as Trolox equivalent (lmol)/mg dry weight of extract were 0.2, 1.4 and 3.0, respectively; in the ABTS test the results were 1.0, 4.7 and 9.8. The antioxidant capacity expressed as ascorbic acid equivalent (lmol)/mg dry weight of each product were 17.2, 76.1 and 207.7, respectively. The scavenging properties of cocoa powder against the superoxide anion, H2O2, HClO, and peroxynitrite were also determined. The IC50 (lg/mL) values in the hypoxanthine/xanthine oxidase test were 77.5, 12.3 and 10.3, for A, B and C, respectively, while as an HOCl scavenger the IC50 (lg/mL) values were 225.4, 73.2 and 21.5. As a peroxynitrite anion scavenger, only extract C had a relevant effect, with IC50 (lg/mL) values of 76.1 or 110.0 in the absence or presence of bicarbonate. None of the extracts tested showed activity in the hydrogen peroxide test, but B and C significantly increased the deoxyribose degradation in the absence of ascorbate. Likewise, none of the extracts inhibited the ferrous or copper chelating activity at 100 lg/mL, but they inhibited the lipid peroxidation in brain homogenates and human plasma through non-enzymatic generation systems, with extract C giving the best IC50 (lg/mL) values: 17.4 and 8.1 against lipid peroxidation in brain homogenates and human plasma, respectively. In conclusion, if the extractive protocol is well characterized, defined and optimized, cocoa could constitute a source of polyphenols for enriching foods, nutraceuticals and alimentary supplements.Facultad de Ciencias Médicas (FCM

Evidence that Nitric Oxide is Involved in the Blood Pressure Lowering Effect of the Peptide AVFQHNCQE in Spontaneously Hypertensive Rats

AVFQHNCQE is an antihypertensive nonapeptide obtained from a chicken foot protein hydrolysate. The present study aims to investigate the mechanisms involved in its blood pressure (BP)-lowering effect. Male (17–20 weeks old) spontaneously hypertensive rats (SHR) were used in this study. Rats were divided into two groups and orally administered water or 10 mg/kg body weight (bw) AVFQHNCQE. One hour post administration, animals of both groups were intra peritoneally treated with 1 mL of saline or with 1 mL of saline containing 30 mg/kg bw Nω-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) synthesis, or with 1 mL of saline containing 5 mg/kg bw indomethacin, which is an inhibitor of prostacyclin synthesis (n = 6 per group). Systolic BP was recorded before oral administration and six hours after oral administration. In an additional experiment, SHR were administered water or 10 mg/kg bw AVFQHNCQE (n = 6 per group) and sacrificed six hours post administration to study the mechanisms underlying the peptide anti-hypertensive effect. Moreover, the relaxation caused by AVFQHNCQE in isolated aortic rings from Sprague Dawley rats was evaluated. The BP-lowering effect of the peptide was not changed after indomethacin administration but was completely abolished by L-NAME, which demonstrates that its anti-hypertensive effect is mediated by changes in endothelium-derived NO availability. In addition, AVFQHNCQE administration downregulated aortic gene expression of the vasoconstrictor factor endothelin-1 and the endothelial major free radical producer NADPH. Moreover, while no changes in plasma ACE activity were observed after its administration, liver GSH levels were higher in the peptide treated group than in the water group, which demonstrates that AVFQHNCQE presents antioxidant properties

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LONG-TERM ADMINISTRATION OF GALLIC ACID DECREASES BLOOD PRESSURE IN METABOLIC SYNDROME ANIMAL MODEL VIA AN IMPROVEMENT OF ENDOTHELIAL FUNCTION

Gallic acid (GA, 3,4,5-trihidroxibenzoic) is a phenolic compound, widely represented in the plant kingdom, which has been demonstrated to exert beneficial health effects, including antihypertensive effect . The aim of this study was to evaluate the chronic antihypertensive effect of GA in hypertensive cafeteria diet-fed rats and the mechanisms involved in this effect. After 8 weeks of cafeteria diet feeding, male Wistar rats (n=6 per group) were daily orally supplemented with GA (6.65 mg/kg), Captopril (50 mg/kg) as a positive control or vehicle as a negative control for 3 weeks. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured by the tail cuff method and thoracic aorta was extracted to evaluate endothelium-dependent genes expression. After 3 weeks of GA administration, there was a significant reduction in blood pressure (BP) (-20 mmHg decrement of SBP and -15 mmHg decrement on DBP) when compared to animals from the vehicle group. Regarding gene expression, GA produced the upregulation of Sirt-1 and eNOS gene expression resulting in an increase of NO production and promoting a vasodilatation effect. In addition, GA downregulated the gene expression of the vasoconstrictor agent, ET-1, which could contribute to BP reduction observed after GA administration. Moreover, the antihypertensive effect of GA could be explained through the overexpression of NOX4 which has been reported to exert vasoprotective effects. Considering these results, we can conclude that GA had chronic antihypertensive effect in cafeteria diet-fed rats through an improvement in the endothelial function

Dose-Related Antihypertensive Properties and the Corresponding Mechanisms of a Chicken Foot Hydrolysate in Hypertensive Rats

The antihypertensive properties of different doses of a chicken foot hydrolysate, Hpp11 and the mechanisms involved in this effect were investigated. Spontaneously hypertensive rats (SHR) were administered water, Captopril (50 mg/kg) or Hpp11 at different doses (25, 55 and 85 mg/kg), and the systolic blood pressure (SBP) was recorded. The SBP of normotensive Wistar-Kyoto (WKY) rats administered water or Hpp11 was also recorded. Additionally, plasmatic angiotensin-converting enzyme (ACE) activity was determined in the SHR administered Hpp11. Moreover, the relaxation caused by Hpp11 in isolated aortic rings from Sprague-Dawley rats was evaluated. Hpp11 exhibited antihypertensive activity at doses of 55 and 85 mg/kg, with maximum activity 6 h post-administration. At this time, no differences were found between these doses and Captopril. Initial SBP values of 55 and 85 mg/kg were recovered 24 or 8 h post-administration, respectively, 55 mg/kg being the most effective dose. At this dose, a reduction in the plasmatic ACE activity in the SHR was found. However, Hpp11 did not relax the aortic ring preparations. Therefore, ACE inhibition could be the mechanism underlying Hpp11 antihypertensive effect. Remarkably, Hpp11 did not modify SBP in WKY rats, showing that the decreased SBP effect is specific to the hypertensive state