La Captación de radicales libres y la inhibición de α-glucosidasa, dos posibles mecanismos involucrados en la actividad antidiabética del ácido oleanólico

This work investigates the role of oleanolic acid (OA), isolated from the olive (Olea europaea L.) leaf, as a radical scavenger and inhibitor of the hydrolyzing enzymes of dietary carbohydrates. New evidence is provided showing that OA may capture 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) and peroxyl radicals, and also exert a strong and non -competitive inhibition of α-glucosidase (IC50 10.11 ± 0.30 μM). The kinetic and spectrometric analyses performed indicate that OA interacts with this enzyme inside a hydrophobic pocket, through an endothermic and non spontaneous process of a hydrophobic nature. These are two possible mechanisms by which OA may facilitate a better control of post-prandial hyperglycaemia and oxidative stress, so contributing to preserving insulin signalling. Obesity, insulin resistance and Type 2 Diabetes Mellitus are considered the first pandemics of the 21st century. In this sense, OA might be used in future preventive and therapeutic strategies, as an ingredient in new drugs and functional foods.Este trabajo estudia el papel del ácido oleanólico (OA), aislado de la hoja de olivo, como secuestrador de radicales libres e inhibidor de enzimas implicados en la hidrolisis de los carbohidratos de la dieta, dos mecanismos por los que el triterpeno podría mitigar la hiperglicemia postprandial y el estrés oxidativo. Se aportan nuevas evidencias que muestran que el OA puede capturar radicales ácido 2,2’-azino-bis-(3-etilbenzotiazolín)-6-sulfónico y peroxilo, y que ejerce una potente inhibición no-competitiva de α-glucosidasa (IC50 10.11±0.30 μM). El análisis cinético y espectrométrico llevado a cabo indica que OA interacciona con este enzima en el interior de un bolsillo hidrofóbico, mediante un proceso endotérmico no espontáneo, de naturaleza hidrofóbica. Estos son dos posibles mecanismos por los cuales el OA puede facilitar un mejor control de la hiperglucemia postprandial y el estrés oxidativo, lo que contribuye a preservar la señalización de la insulina. La obesidad, la resistencia a la insulina y la diabetes mellitus tipo 2 se consideran la primera pandemia del siglo XXI. En este sentido, el OA podría ser utilizado en futuras estrategias preventivas y terapéuticas, como ingrediente de nuevos fármacos y alimentos funcionales

PREVALENCE OF UNKNOWN DIABETES AND IMPAIRED GLUCOSE TOLERANCE IN PATIENTS WITH IMPAIRED FASTING GLUCOSE

There are many community-based studies on the prevalence of diabetes, impaired glucose tolerance (IGT) and impaired fasting glucose (IFG). However, studies on the prevalence of IGT and diabetes unknown in patients with IFG, by 75-g oral glucose tolerance test (OGTT), are few and small.CIBEROBN is an Instituto de Salud Carlos III initiative. This work has been co-financied by CIBEROBN, Research Grants of the Ministerio de Economía y Competitividad of Spain (Instituto de Salud Carlos III: PI10/00913), and Consejería de Salud de la Junta de Andalucía of Spain (PI-0037/2008 and PI-0112-2013).Peer Reviewe

Dietary glycemic index and glycemic load are positively associated with risk of developing metabolic syndrome in middle-aged and elderly adults

© 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society. Objectives To evaluate how glycemic index (GI) and glycemic load (GL) are associated with the metabolic syndrome (MetS) and its features in middle-aged and elderly adults at high cardiovascular risk. Design Prospective, longitudinal, population-based cohort. Setting PREvenciõn con DIeta MEDiterránea study. Participants Men and women (N = 6,606) divided into three age groups (<65, 65-74, ≥75). Measurements Energy and nutrient intake was evaluated using a validated 137-item food frequency questionnaire. MetS and its features were defined in accordance with the criteria of the American Heart Association and National Heart, Lung, and Blood Institute. Results A positive association was observed between GI and MetS prevalence in the youngest and middle age groups for participants without diabetes mellitus, but no relationship was found for those with diabetes mellitus. During the median follow-up of 4.8 years, higher GI and GL were related to greater risk of MetS in the middle age group, independent of the presence of diabetes mellitus. Changes in dietary GI were associated with risk of developing the high fasting glucose component of the MetS in the oldest age category, and changes in dietary GL were associated with risk of developing abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol, and high blood pressure in the youngest age category. Conclusion Dietary GI and GL have a potential role in the development of MetS and associated clinical features, with particular age-dependent considerations.Funded by: Centro Nacional de Investigaciones Cardiovasculares. Grant Number: 06/2007; Instituto de Salud Carlos III; Fondo de Investigación Sanitaria PI. Grant Number: 07/0473; Ministerio de Ciencia e Innovación. Grant Numbers: AGL-2009–13906-C02, AGL2010–22319-C03; Ministerio de Sanidad-Plan Nacional de Drogas. Grant Number: 2010/087; Fondo de Investigaciones Sanitarias. Grant Number: PI1002658 Fundación Mapfre 2010 Government of the Basque Country. Grant Number: IT386–10 University of the Basque Country. Grant Number: UFI 11/32 Catalan government Miguel Servet. Grant Number: 06/00100Peer Reviewe

Dietary intake of phylloquinone is related to a reduced risk of all-cause mortality: the predimed study

Resumen del trabajo presentado en el 20th International Congress of Nutrition, celebrado en Granada (España) del 15 al 20 de septiembre de 2013.[Background and objectives]: Vitamin K has been associated with a reduced risk of CHD and fatal cancer. Dietary menaquinones intake has been associated with cancer mortality. However, the association between the dietary intake of vitamin K and all-cause mortality has not been evaluated in a Mediterranean population at high cardiovascular risk.[Methods]: A prospective analysis was conducted in 7216 participants in the framework of the PREDIMED cohort (median follow-up: 4.8y). Energy and nutrient intakes were evaluated using a previously validated 137-item food frequency questionnaire. Dietary phylloquinone and menaquinone intake was calculated using the USDA database and previous published Abstracts Ann Nutr Metab 2013;63(suppl 1):1– 1960 921 data, respectively. All-cause mortality was verified by medical records and consultation of National Death Index. Cox proportional hazard models were fitted to assess the relative risk of all-cause mortality.[Results]: At baseline, energy-adjusted dietary phylloquinone intake was associated with a significantly reduced risk of all-cause mortality after controlling for potential confounders (HR: 0.64; 95% CI: 0.43, 0.96). No significant associations were found between quartiles of energy adjusted dietary menaquinones intake and risk of all-cause mortality. In a longitudinal manner, subjects who increase their consumption of vitamin K, phylloquinone or menaquinone, had a lower risk of allcause mortality (HR: 0.58; 95% CI: 0.45, 0.74 and HR: 0.59; 95% CI: 0.45, 0.78, respectively) compared with subjects who decrease their consumption.[Conclusions]: The results showed that an increase of dietary intake of vitamin K is related with a reduced risk of all-cause mortality in a Mediterranean population at high cardiovascular risk

Primary prevention of cardiovascular disease with a Mediterranean diet

BACKGROUND: Observational cohort studies and a secondary prevention trial have shown an inverse association between adherence to the Mediterranean diet and cardiovascular risk. We conducted a randomized trial of this diet pattern for the primary prevention of cardiovascular events. METHODS: In a multicenter trial in Spain, we randomly assigned participants who were at high cardiovascular risk, but with no cardiovascular disease at enrollment, to one of three diets: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts, or a control diet (advice to reduce dietary fat). Participants received quarterly individual and group educational sessions and, depending on group assignment, free provision of extra-virgin olive oil, mixed nuts, or small nonfood gifts. The primary end point was the rate of major cardiovascular events (myocardial infarction, stroke, or death from cardiovascular causes). On the basis of the results of an interim analysis, the trial was stopped after a median follow-up of 4.8 years. RESULTS: A total of 7447 persons were enrolled (age range, 55 to 80 years); 57% were women. The two Mediterranean-diet groups had good adherence to the intervention, according to self-reported intake and biomarker analyses. A primary end-point event occurred in 288 participants. The multivariable-adjusted hazard ratios were 0.70 (95% confidence interval [CI], 0.54 to 0.92) and 0.72 (95% CI, 0.54 to 0.96) for the group assigned to a Mediterranean diet with extra-virgin olive oil (96 events) and the group assigned to a Mediterranean diet with nuts (83 events), respectively, versus the control group (109 events). No diet-related adverse effects were reported. CONCLUSIONS: Among persons at high cardiovascular risk, a Mediterranean diet supplemented with extra-virgin olive oil or nuts reduced the incidence of major cardiovascular events

Mediterranean dietary pattern and depression: the PREDIMED randomized trial

Background: A few observational studies have found an inverse association between adherence to a Mediterranean diet and the risk of depression. Randomized trials with an intervention based on this dietary pattern could provide the most definitive answer to the findings reported by observational studies. The aim of this study was to compare in a randomized trial the effects of two Mediterranean diets versus a low-fat diet on depression risk after at least 3 years of intervention. Methods: This was a multicenter, randomized, primary prevention field trial of cardiovascular disease (Prevención con Dieta Mediterránea (PREDIMED Study)) based on community-dwelling men aged 55 to 80 years and women aged 60 to 80 years at high risk of cardiovascular disease (51% of them had type 2 diabetes; DM2) attending primary care centers affiliated with 11 Spanish teaching hospitals. Primary analyses were performed on an intention-to-treat basis. Cox regression models were used to assess the relationship between the nutritional intervention groups and the incidence of depression. Results: We identified 224 new cases of depression during follow-up. There was an inverse association with depression for participants assigned to a Mediterranean diet supplemented with nuts (multivariate hazard ratio (HR) 0.78; 95% confidence interval (CI) 0.55 to 1.10) compared with participants assigned to the control group, although this was not significant. However, when the analysis was restricted to participants with DM2, the magnitude of the effect of the intervention with the Mediterranean diet supplemented with nuts did reach statistical significance (multivariate HR = 0.59; 95% CI 0.36 to 0.98). Conclusions: The result suggest that a Mediterranean diet supplemented with nuts could exert a beneficial effect on the risk of depression in patients with DM2

Mediterranean Diet and atherothrombosis biomarkers: a randomized controlled trial

Scope. To assess whether following a Mediterranean diet (MedDiet) improved atherothrombosis biomarkers in high cardiovascular risk individuals. Methods and results. In 358 random volunteers from the PREvención con DIeta MEDiterránea trial, we assessed the 1-year effects on atherothrombosis markers of an intervention with MedDiet, enriched with virgin olive oil (MedDiet-VOO; n=120) or nuts (MedDiet-Nuts; n=119) versus a low-fat control diet (n=119). We also studied whether large increments in MedDiet adherence (≥3 score points, relative to compliance decreases) and intake changes in key food items were associated with 1-year differences in biomarkers. We observed differences between 1-year changes in the MedDiet-VOO intervention and control diet on the activity of platelet activating factor acetylhydrolase in HDLs (+7.5% [95% confidence interval: 0.17; 14.8]) and HDL-bound α1-antitrypsin levels (- 6.1% [-11.8; -0.29]), and between the MedDiet-Nuts intervention and the control arm on non-esterified fatty acid concentrations (-9.3% [-18.1; -0.53]). Large MedDiet adherence increments were associated with less fibrinogen (-9.5% [-18.3; -0.60]) and non-esterified fatty acid concentrations (-16.7% [-31.7; -1.74]). Increases in nut, fruit, vegetable, and fatty fish consumption, and decreases in processed meat intake were linked to beneficial changes in atherothrombosis biomarkers. Conclusion. Following a MedDiet improved atherothrombosis biomarkers in high cardiovascular risk individual

Alcohol intake, wine consumption and the development of depression: the PREDIMED study

Background: Alcoholic beverages are widely consumed. Depression, the most prevalent mental disorder worldwide, has been related to alcohol intake. We aimed to prospectively assess the association between alcohol intake and incident depression using repeated measurements of alcohol intake. Methods: We followed-up 5,505 high-risk men and women (55 to 80 y) of the PREDIMED Trial for up to seven years. Participants were initially free of depression or a history of depression, and did not have any history of alcohol-related problems. A 137-item validated food frequency questionnaire administered by a dietician was repeated annually to assess alcohol intake. Participants were classified as incident cases of depression when they reported a new clinical diagnosis of depression, and/or initiated the use of antidepressant drugs. Cox regression analyses were fitted over 23,655 person-years. Results: Moderate alcohol intake within the range of 5 to 15 g/day was significantly associated with lower risk of incident depression (hazard ratio (HR) and 95% confidence interval (95% CI) = 0.72 (0.53 to 0.98) versus abstainers). Specifically, wine consumption in the range of two to seven drinks/week was significantly associated with lower rates of depression (HR (95% CI) = 0.68 (0.47 to 0.98)). Conclusions: Moderate consumption of wine may reduce the incidence of depression, while heavy drinkers seem to be at higher risk

American heart association's life simple 7 and the risk of atrial fibrillation in the PREDIMED study cohort

Background and aims The American Heart Association proposed 7 ideal cardiovascular health metrics (Life's Simple 7 [LS7]) namely, not smoking, body mass index <25 kg/m2, healthy diet, moderate physical activity ≥150 min/week, total blood cholesterol <200 mg/dL, blood pressure <120/80 mmHg and fasting blood glucose <100 mg/dL. Our objective was to assess the association between these LS7 metrics and the incidence of atrial fibrillation (AF). Methods and results A total of 6,479 participants of the PREDIMED study were included. We calculated the participants’ baseline LS7 index ranging 0–7 points to categorize them according to their adherence to these LS7 health metrics. Multivariable Cox regression models were used to estimate Hazard Ratios (HR) and their 95% Confidence Intervals (95% CI). After a median follow-up of 4.8 years, we identified 250 incident cases of AF. After adjusting for potential confounders, adherence to LS7 index was not associated with the incidence of AF (adjusted HR 0.90 [95% CI: 0.56–1.45] for highest vs. lowest LS7 categories). Body mass index <25 kg/m2 was the only health metric individually associated with a lower risk of AF (HR 0.36 [95% CI: 0.16–0.78]). Conclusions In a high cardiovascular risk Spanish population, adherence to American Heart Association's LS7 metrics was not associated with the risk of incident AF