ABSTRACT Background: Medical students experience high levels of psychological stress during clinical training. However, most medical curricula do not teach self-care skills. The COVID-19 pandemic has disrupted medical education causing increased distress among students. Aim: To report the implementation and impact of an eight-week multifaceted mindfulness-based self-care program on medical students’ distress and well-being during the COVID-19 pandemic. Material and Methods: One hundred twenty-three fourth-year medical students attended the program as part of a mandatory course from April to May 2020, during the rising phase of COVID-19 in Chile. They were evaluated using validated tests before and immediately after the program. The measures included burnout, dispositional mindfulness, perceived stress, traumatic stress reactions, general well-being, resilience, and stress coping strategies. Results: Burnout prevalence decreased from 48% to 24%, whereas students with high dispositional mindfulness increased from 25% to 44%. Burnout reduction was mostly due to decreased emotional exhaustion. Additionally, students reported lower levels of stress, self-blaming, and traumatic stress reactions alongside an increased use of active coping strategies and resilience levels after the program. Conclusions: A formal educational intervention, teaching self-awareness and self-regulation skills can help reduce medical students’ distress and promote their well-being even amidst a pandemic.

Antecedentes: Los estudiantes de medicina experimentan altos niveles de estrés y burnout durante la formación clínica. Sin embargo, la mayoría de los planes de estudios médicos no enseñan habilidades de autocuidado. La pandemia de COVID-19 ha conmocionado la educación médica provocando mayor distrés entre los estudiantes. Objetivo: Informar sobre la implementación y el impacto de un programa multifacético de autocuidado -basado en mindfulness (atención consciente)-sobre el distrés y el bienestar de los estudiantes de medicina durante la pandemia de COVID-19. Material y Métodos: Ciento veintitrés estudiantes de medicina de cuarto año asistieron al programa como parte de un curso obligatorio de abril a mayo de 2020, durante la fase ascendente de COVID-19 en Chile. Fueron evaluados mediante pruebas validadas antes e inmediatamente después del programa. Las medidas incluyeron burnout, mindfulness disposicional, estrés percibido, reacciones de estrés traumático, bienestar general, resiliencia y estrategias de afrontamiento del estrés. Resultados: La prevalencia del burnout disminuyó del 48% al 24%, mientras que los estudiantes con alto mindfulness aumentaron del 25% al 44%. La reducción del burnout se debió principalmente a la disminución del agotamiento emocional. Además, los estudiantes informaron niveles más bajos de estrés, autoinculpación y reacciones de estrés traumático junto con un mayor uso de estrategias activas de afrontamiento y mayores niveles de resiliencia, después del programa de autocuidado. Conclusiones: Una intervención educativa formal que enseñe habilidades de autoconciencia y autorregulación puede ayudar a reducir el burnout de los estudiantes de medicina y promover su bienestar incluso en medio de una pandemia.

Abstract: SR-B1 KO/ApoER6 1h/h mice fed a high saturated fat diet develop severe coronary atheromatosis, and cardiac failure with a high mortality rate. Cardiac remodeling under these conditions has not been well studied. Aim: To evaluate the time course of left ventricular function, cardiac remodeling and survival associated to the administration of an atherogenic diet. Method: Homozygote SR-B1 KO/ApoER6 1h/h mice received an atherogenic diet for 8 weeks. Mice receiving a normal diet served as controls. Survival rate, myocardial fibrosis, cardiomyocyte size, apoptosis and infiltration by inflammatory or mononuclear cells were compared between groups. A TUNEL technique was used to evaluate apoptosis. Results: A 46.7% survival reduction compared to controls was observed in the experimental group (p<0.01), due to left ventricular and atrial dilatation associated to a decrease in ejection fraction (79,3 ± 1,3% vs 66 ± 3,7%, p<0,01, respectively). Also, an increased cardiac weight, 2.6 times greater was observed in the experimental group, compared to controls. Mice receiving the atherogenic diet showed an 80% increased lung weight. There was no evident change in cardiomyocytes, but there was more (7.9 times) cardiac fibrosis (p<0.01) and 55.9 times more apoptotic cells. (p<0.01), along with a greater number of inflammatory cells and ED1 mononuclear cells. Conclusion: Mice receiving an atherogenic diet develop heart failure and reduced survival rate. This is associated with cardiac remodeling with underlying apoptosis an ventricular wall fibrosis. It is posible that wall edema might contribute to the observed cardiac remodeling.

Resumen: Introducción: Los ratones SR-B1 KO/ApoER6 1h/h que son alimentados con una dieta rica en grasas saturadas, desarrollan enfermedad coronaria aterosclerótica severa, complicaciones isquémicas e insuficiencia cardíaca, con alta mortalidad. Los estudios con este modelo se han enfocado fundamentalmente en la enfermedad coronaria y menos en el remodelado cardíaco. El objetivo del trabajo ha sido caracterizar el remodelado miocárdico, evaluar la evolución temporal de la función ventricular izquierda y la sobrevida asociada a enfermedad cardíaca por ateromatosis. Método: Ratones homocigotos SR-B1 KO/ApoER6 1h/h fueron alimentados por 8 semanas con dieta aterogénica o dieta normal y se comparó la sobrevida en ambos grupos. A las 4 semanas se realizó un ecocardiograma bidimensional. En los ratones eutanasiados se evaluó en la pared cardíaca fibrosis miocárdica y tamaño de los cardiomiocitos por morfometría, apoptosis con técnica de TUNEL e infiltración por células inflamatorias mononucleares (ED1) por inmunohistoquímica. Resultados: En el grupo que recibió dieta aterogénica la sobrevida se redujo en 46,7% (p < 0.001), debido a muerte súbita y a falla cardíaca progresiva. En este grupo, a las 4 semanas se observó dilatación de cavidades izquierdas y disminución de la fracción de eyección del ventrículo izquierdo en comparación con el grupo control (79,3 ± 1,3% vs 66 ± 3,7%, p<0,01). También se observó aumento de la masa cardíaca relativa de 2.1 veces (p<0,001) y del peso pulmonar relativo en 80% (p<0,001), sin cambios en las dimensiones de los cardiomiocitos. En el miocardio de los ratones que recibieron dieta aterogénica hubo un aumento de la fibrosis cardíaca de 7.9 veces (p < 0.01) y del número de cardiomiocitos apoptóticos en 55.9 veces (p < 0.01), junto a un aumento del número de células inflamatorias mononucleares ED1. Conclusiones: En el modelo de falla cardíaca severa de etiología isquémica con alta mortalidad en el ratón homocigoto SR-B1 KO/ApoER6 1h/h sometido a una dieta aterogénica, con falla cardíaca izquierda por disfunción sistólica, el remodelado patológico del miocardio está dado fundamentalmente por apoptosis y fibrosis. También se observa un aumento discreto de macrófagos en la pared cardíaca. Es posible que el edema parietal también pueda ser un mecanismo de remodelado relevante en este modelo.

Background Despite aggressive treatment aimed at lowering LDL cholesterol (LDL-C) levels with statins, there is a high residual prevalence of cardiovascular diseases, which may depend on plasma cholesterol transported in other atherogenic lipoproteins. Aims To describe non-HDL cholesterol (non-HDL-C) levels in the Chilean population and their association with diabetes mellitus and cardiovascular disease. To evaluate compliance with non-HDL-C therapeutic goals -according to individual cardiovascular risk- at different levels of triglycerides, in comparison with LDL-C goal achievement. Material and Methods: We analyzed data from 2,792 Chilean subjects aged ≥ 15 years who were included in the 2009-2010 National Health Survey and had valid data for blood lipids, diabetes, and cardiovascular disease. Results Forty five percent of subjects had high non-HDL-C levels. The proportion of diabetic and non-diabetic subjects with high non-HDL-C levels was 81 and 42%, respectively (p < 0.01). A significant discordance was observed in the achievement of therapeutic objectives when LDL-C or non-HDL-C levels were considered, particularly in presence of triglycerides ≥ 150 mg/dl. Namely, 8% of the population showed elevated levels of high non-HDL-C despite adequate LDL-C levels. Conclusions Evaluation and management of elevated non-HDL-C in patients with adequate levels of LDL-C seems worthwhile considering the discordance observed between these blood cholesterol fractions. This strategy may be effective to reduce the residual cardiovascular risk in the Chilean population.

Background: The burnout syndrome affects more than half of students and professionals involved in healthcare worldwide and is characterized by emotional exhaustion, depersonalization and a low perception of self-efficacy. Several studies indicate that when students are burnt-out, clinical work, professionalism and ethical behavior, as well as empathy, are negatively affected, while the risk of academic attrition, depression and suicidal ideation tend to increase. At a national level, recent information shows that one out of every two medical students suffer burnout at the beginning of the clinical cycle, a situation that does not improve after finishing undergraduate medical training. There is no consensus on which are the most appropriate strategies to face the problem of burnout in students and health-care professionals. Some studies indicate that the experience of medical and health educators may be key to the design of effective strategies to address this problem. Aim: To identify the burnout risk and protection factors of students at different medical schools. Material and Methods: In this study -in which 34 expert health educators from eight Chilean medical schools and other health-related schools participated- we used a qualitative methodology based on the appreciative inquiry to explore the key elements associated with the occurrence of burnout, identify protective and risk factors, as well as discuss possible effective interventions to prevent it. Results: There are personal, academic and contextual elements that act as protective or risk factors of burnout. In addition, the educators identified key elements to design organizational and curricular interventions to face the problem of burnout at a local level. Conclusions: Burnout is a serious problem in the formation of health care professionals. Teacher training aimed at promoting student'well-being must include the teaching of communication skills that consider both the generation gap and the profile of the professional medical schools intend to form.

Abstract Eggs are a highly nutritive food. They contain high quality protein and several nutrients with potential health benefits. Nevertheless, the appearance of cardiovascular disease as an important public health issue, with high morbidity and mortality rates worldwide, along with the identification of high blood cholesterol levels as a risk factor for this disease, was responsible for the advice to limit dietary cholesterol (and, therefore, eggs) that was promoted by health care professionals and institutions during the 70s. To date, several cohort studies show that the intake of one egg a day does not increase cardiovascular risk in the general population. However, this evidence is not clear among diabetic patients, and raises the question whether its consumption in large quantities is entirely safe in this particular population. Additionally, intervention studies have shown that egg consumption does not adversely affect cardiovascular risk factors neither in healthy individuals nor in those with cardiometabolic disease. Moreover, these studies suggest that the incorporation of egg to the diet could bring additional benefits such as promoting a less atherogenic lipid profile.

Resumen El huevo es un alimento que aporta proteína de alta calidad y numerosos nutrientes con potenciales beneficios para la salud. Sin embargo, la aparición de la enfermedad cardiovascular como importante causa de morbilidad y mortalidad en el mundo, junto con la identificación de los niveles elevados de colesterol plasmático como factor de riesgo para esta patología, llevó, en los años 70, a profesionales e instituciones de salud a limitar el consumo de colesterol y, por tanto, de huevo en la población. Hasta la fecha, los análisis de cohortes prospectivas tienden a mostrar que el consumo de hasta un huevo diario no aumenta significativamente el riesgo cardiovascular en la población sana. Sin embargo, esta evidencia no es clara en los pacientes diabéticos y pone en duda que este alimento consumido en cantidades elevadas sea del todo inocuo en esta población en particular. Asimismo, estudios de intervención a corto plazo han mostrado que, en general, el consumo de huevo no afecta negativamente los factores de riesgo cardiovascular en individuos sanos así como en aquellos con enfermedad cardiometabólica. Además, estos estudios sugieren que la incorporación del huevo en la dieta podría traer beneficios adicionales, promoviendo un perfil lipídico menos aterogénico.

The Mediterranean diet is currently considered a healthy dietary pattern. It includes a great variety of foods, which are eaten in moderation and within a positive social environment. The generic term “Mediterranean diet” was born after the “Seven Countries Study” led by Ancel Keys around 1960. This dietary pattern is characterized by a high intake of fruits and vegetables, whole grains, legumes, nuts, fish, white meats and olive oil. It also includes moderate consumption of fermented dairy products, low intake of red meat and drinking wine with moderation during meals. Nutritionally, this diet is low in saturated fats and animal protein, high in antioxidants, fiber and monounsaturated fats, and exhibits an adequate omega-6/omega-3 fatty acid balance. The main bioactive compounds, which explain the health benefits of this dietary pattern, are antioxidants, fiber, monounsaturated and omega-3 fatty acids, phytosterols and probiotics. This diet is not exclusively confined to the Mediterranean Basin. Central Chile has a Mediterranean climate and our agriculture and culinary traditions are similar to those found in Mediterranean countries. Therefore, it is fundamental to increase awareness about the richness of our natural produce as well as our culinary culture, which may bring many health benefits and improve the quality of life in our population.

Levels, lipid and protein composition, and functional properties of high density lipoproteins (HDL) determine the biological functions of this lipoprotein fraction and its protective role in cardiovascular disease. These HDL-related parameters can be modulated by pharmacological and non-pharmacological interventions. In the last two decades, it has been established that consumption of Mediterranean diet, especially when supplemented with extra virgin olive oil, improves different quantitative parameters (cholesterol levels and number of particles, as well as particle size) and functional properties (cell cholesterol efflux, cholesterol esterification as well as antioxidant, endothelial relaxation, and anti-inflammatory activities) of HDL in humans. Most likely, these effects contribute to the widely demonstrated benefits of Mediterranean diet intake against different chronic diseases.

Los niveles, la composición lipídica y proteica y las propiedades funcionales de las li-poproteínas de alta densidad (HDL) determinan las funciones biológicas de esta fracción lipoproteica y su papel protector contra el desarrollo de enfermedad cardiovascular. Estos parámetros de las HDL pueden ser modulados por intervenciones farmacológicas y no farmacológicas. En las dos últimas décadas, se ha establecido que el consumo de una dieta mediterránea, especialmente cuando se suplementa con aceite de oliva extra virgen, mejora diferentes parámetros cuantitativos (niveles de colesterol y número de partículas, en particular de mayor tamaño) y cualitativo-funcionales (capacidad de eflujo celular y esterificadora de colesterol libre, así como las actividades antioxidantes, de relajación endotelial y antiinflamatoria) de las partículas de HDL en humanos. Estos efectos probablemente contribuyen a la acción protectora ampliamente demostrada para la dieta mediterránea frente a diferentes enfermedades crónicas.

RESUMEN El huevo es un alimento altamente nutritivo con potenciales beneficios para la salud. Sin embargo, debido a su elevado contenido de colesterol, su consumo ha sido restringido en la población general. El objetivo de esta revisión es difundir en la comunidad científica la evidencia más reciente sobre los efectos del consumo de huevo específicamente en sujetos con diabetes mellitus. Estudios observacionales muestran que el consumo de hasta un huevo al día no se asocia a una mayor prevalencia de enfermedad cardiovascular en la población general, pero podría aumentar el riesgo entre los diabéticos. Asimismo, algunos de estos estudios han mostrado que un elevado consumo de huevo se asocia a un aumento en la incidencia de diabetes en la población general. Por otro lado, estudios de intervención a corto plazo en este subgrupo muestra que el consumo de huevo no afecta negativamente los factores de riesgo cardiovascular ni control glicémico en estos pacientes. Además, su consumo podría aumentar el impacto del uso de dietas hipocalóricas en la disminución de peso corporal, una importante herramienta en el manejo médico de la diabetes.

RESUMO Neste relato se examinam os desafios de realizar um estudo transversal multicêntrico em países com culturas diversas e os ensinamentos tirados. O Estudo Latino-americano de Nutrição e Saúde (ELANS) serviu de estudo de viabilidade, englobando as cidades mais populosas de oito países da América Latina (Argentina, Brasil, Chile, Colômbia, Costa Rica, Equador, Peru e Venezuela) em 2014–2015, representando cerca de 40% da população das Américas. A amostra pretendida compreendeu 9.000 indivíduos com 15 a 65 anos de idade e foi estratificada por localização geográfica (exclusivamente áreas urbanas), sexo, idade e nível socioeconômico. Os seis principais desafios identificados foram: estruturar as equipes e selecionar as sedes, elaborar um único protocolo, obter as aprovações dos comitês de ética, realizar trabalho de campo simultâneo, assegurar a qualidade dos dados e extrair os dados e manter a consistência em todas as bases de dados. Os ensinamentos tirados demonstram serem imprescindíveis harmonização, estudo-piloto, uniformidade dos procedimentos, ótimo controle da qualidade dos dados e comunicação e colaboração entre as sedes. Entre as barreiras estão a complexidade organizacional, recrutamento de colaboradores e pessoal de pesquisa, cooperação institucional, desenvolvimento de infraestrutura e identificação dos recursos. Antes do início do trabalho de campo, deve-se chegar a um consenso sobre medidas e resultados uniformes e metodologia de coleta de dados assim como um plano para o gerenciamento e análise dos dados, comunicação, publicação e disseminação dos resultados dos estudos. Apesar da sua complexidade, tais estudos têm um grande potencial de fundar uma base científica para estudos de nutrição, atividade física e outros tópicos relacionados à saúde, ao mesmo tempo que facilitam comparações entre os países da América Latina.

ABSTRACT This report examines the challenges of conducting a multicenter, cross-sectional study of countries with diverse cultures, and shares the lessons learned. The Latin American Study of Nutrition and Health (ELANS) was used as a feasibility study involving the most populous cities of eight countries in Latin America (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela) in 2014–2015, about 40% of the population of the Americas. The target sample included 9 000 individuals, 15–65 years of age, and was stratified by geographic location (only urban areas), gender, age, and socioeconomic status. Six principal challenges were identified: team structuring and site selections; developing a single protocol; obtaining ethic approvals; completing simultaneous fieldwork; ensuring data quality; and extracting data and maintaining consistency across databases. Lessons learned show that harmonization, pilot study, uniformity of procedures, high data quality control, and communication and collaboration across sites are imperative. Barriers included organizational complexity, recruitment of collaborators and research staff, institutional cooperation, development of infrastructure, and identification of resources. Consensus on uniform measures and outcomes and data collection methodology, as well as a plan for data management and analysis, communication, publication, and dissemination of study results should be in place prior to beginning fieldwork. While challenging, such studies offer great potential for building a scientific base for studies on nutrition, physical activity, and other health topics, while facilitating comparisons among countries.

RESUMEN En este informe se examinan los retos de llevar a cabo un estudio transversal multicéntrico en países con culturas diversas y se transmiten las enseñanzas extraídas. Se usó el Estudio Latinoamericano de Nutrición y Salud (ELANS) como un estudio de factibilidad realizado en el período 2014–2015, que incluyó las ciudades más populosas de ocho países de América Latina (Argentina, Brasil, Chile, Colombia, Costa Rica, Ecuador, Perú y Venezuela) y abarcó a cerca de 40% de la población de la Región de las Américas. La muestra establecida incluyó a 9 000 personas de 15 a 65 años de edad, y fue estratificada según la ubicación geográfica (solo zonas urbanas) y por sexo, edad y situación socioeconómica. Se encontraron seis retos principales: estructurar los equipos y seleccionar los sitios; preparar un protocolo único; obtener las aprobaciones éticas; terminar simultáneamente el trabajo sobre el terreno; velar por la calidad de los datos y extraer datos y mantener la uniformidad en todas las bases de datos. Las enseñanzas extraídas muestran que la armonización, los estudios piloto, la uniformidad de los procedimientos, el riguroso control de la calidad de los datos y la comunicación y colaboración entre todos los sitios son imperativos. Los obstáculos incluyeron la complejidad de la organización, el reclutamiento de colaboradores y personal de investigación, la cooperación institucional, el desarrollo de infraestructura y la definición de los recursos. Antes de comenzar el trabajo sobre el terreno, se debe llegar a un consenso acerca de mediciones y resultados uniformes y la metodología de recopilación de datos, así como un plan para la gestión y el análisis de los datos y la comunicación, publicación y difusión de los resultados del estudio. A pesar de que estos estudios constituyen un desafío, hacen posible establecer una base científica para los estudios sobre la nutrición, la actividad física y otros temas de salud, al facilitar las comparaciones entre los países de América Latina.

Background: Availability of brief dietary indexes that can effectively evaluate dietary patterns and their association with health is critical for prevention and management of several chronic disease conditions. Aim: To adapt a self-applicable Mediterranean Dietary Index in Chile (Chilean-MDI). Material and Methods: The Chilean-MDI was developed based on a previous Mediterranean eating score that was adapted to Chilean dietary habits. This index was further validated in a sample of 153 adults by comparing the concordance between the results obtained by self-application of the Chilean-MDI with those obtained by a trained nutritionist. Additionally, the index was applied in a sample of 53,366 Chilean adults in order to describe the diet quality of our population. Results: There was an adequate concordance between findings obtained by self-application of the Chilean-MDI and those achieved by the nutritionist. The application of the index in Chilean adult population showed a better diet quality (high Mediterranean diet adherence) among women, with advanced age and among people with higher educational levels. Conclusions: The Chilean-MDI can be successfully self-applied to portray the overall diet quality in the Chilean adult population. Additionally, this dietary index describes overall food intake in Chilean adults, showing demographic trends that are comparable to those obtained with similar indexes applied in other populations.

The Mediterranean diet is currently considered a functional diet with an increasing amount of scientific evidence that supports its beneficial effects in human health. Several observational cross-sectional and prospective cohort studies show an association between this diet and a lower prevalence and incidence of chronic diseases, such as cardiovascular disease, cancer, metabolic syndrome, diabetes, and neurodegenerative diseases as well as a reduced overall mortality. Additionally, clinical interventional studies, particularly the PREDIMED (Prevención con Dieta Mediterránea) initiative, have shown, with high quality scientific evidence, that a Mediterranean diet -supplemented either with olive oil or nuts- can lower by 30% the incidence of cardiovascular disease, reverse the metabolic syndrome, and prevent the development of diabetes and aging-related cognitive decline. Chile has one of the five Mediterranean ecosystems in the world, and therefore the implementation of this food pattern and lifestyle in our country may determine large benefits to the health status and quality of life in the Chilean population.

Background: Increased serum levels of LDL cholesterol and/or decreased values of HDL cholesterol are very relevant for atherosclerotic cardiovascular disease. Low HDL cholesterol is the most prevalent dyslipidemia in the Chilean population. Regarding reduced HDL cholesterol and high triglyceride levels, fibrates, nuclear receptor PPAR-a agonists that modulate transcription of genes involved in lipid metabolism, represent an important alternative for pharmacological management of dyslipidemia. However, recent clinical studies have been inconclusive with respect to their real benefit on atherosclerosis when used in combination with statins. Aim: To evaluate the impact of fibrate administration on HDL cholesterol metabolism and antioxidant plasma functionality using the mouse as experimental model. Methodology: Using wild-type C57BL/6 mice, ciprofibrate was administered at 0.2% in chow diet for 7 days. After treatment, plasma cholesterol and triglycerides levels, hepatic expression of key proteins involved in HDL cholesterol metabolism, liver cholesterol content, biliary cholesterol secretion, and plasma oxidative damage and antioxidant function were analyzed. Results: Ciprofibrate treatment significantly decreased plasma triglycerides levels and hepatic HDL receptor SR-BI expression. This latter finding was associated with increased HDL particle size, without changes in HDL cholesterol levels. Furthermore, ci-profibrate decreased hepatic expression of cholesterol transporters ABCG1 and ABCG8, but not ABCA1, which correlated with reduced liver cholesterol content and increased biliary cholesterol secretion. Fina-lly, fibrate therapy improved plasma antioxidant func-tion, even though increased nitrosative plasma protein damage was detected. Conclusion: This study has provided new information on metabolic and functional effects derived from fibrate use in mice and it may help to better understand recent clinical findings using this lipid-lowering drug class in humans.

Antecedentes: Las dislipidemias, ya sea un aumento en los niveles de colesterol LDL y/o una disminución en las cifras de colesterol HDL, son muy relevantes para el desarrollo de la enfermedad cardiovascular ateroesclerótica, siendo el colesterol HDL bajo la dislipidemia más frecuente en la población chilena. Con respecto al colesterol HDL bajo y los tri -glicéridos elevados, los fibratos, agonistas del receptor nuclear PPAR-a que modula la transcripción de genes involucrados en el metabolismo de lípidos, representan una importante alternativa de manejo farmacológico de las dislipidemias. Sin embargo, estudios clínicos recientes no han sido concluyentes con respecto a su beneficio real sobre el control de la ateroesclerosis cuando se usan combinados con estatinas. Objetivo: Evaluar el impacto de la administración de fibratos sobre el metabolismo del colesterol HDL y la función antioxidante del plasma usando el ratón como modelo experimental. Metodología: Los ratones de la cepa C57BL/6 fueron tratados con ciprofibrato al 0,2% en dieta control durante 7 días. Luego del tratamiento, se analizaron los niveles de colesterol plasmático y triglicéridos, la expresión hepática de proteínas claves involucradas en el metabolismo de colesterol HDL, el contenido de colesterol hepático, la secreción de colesterol biliar y el daño oxidativo y la función antioxidante plasmática. Resultados: El tratamiento con ciprofibrato disminuyó significativamente los niveles de triglicéridos plasmáticos y la expresión hepática del receptor de HDL SR-BI, efecto que se correlacionó con un aumento en el tamaño de las partículas de HDL, pero no en los niveles de colesterol HDL. Además, el ciprofibrato disminuyó los niveles proteicos de los transportadores de colesterol ABCG1 y ABCG8, aunque no modificó ABCA1, en conjunto con una reducción del contenido hepático de colesterol y un aumento en la secreción de colesterol hacia la bilis. Finalmente, el uso de este hipolipemiante mejoró la función antioxidante del plasma, aunque se detectó un aumento en el daño nitrosativo de las proteínas plasmáticas. Conclusión: Este estudio ha permitido obtener nueva información sobre el efecto metabólico y funcional de la administración de fibratos en ratones, lo cual podría ayudar comprender los resultados de estudios clínicos recientes que han usado esta clase de hipolipemiantes en humanos.

Introduction: metabolic syndrome (MS) is a clustering of risk factors known to promote cardiovascular disease and diabetes. Environmental factors, such as unhealthy diet, play a major role in the development of this condition. In this study, we evaluated the prevalence of MS and its association with food intake quality among Chilean adults. Methods: we analyzed data of 2 561 adults (. 18 years-old) included in the last National Health Survey (NHS 2009-2010) who had appropriate information to diagnose MS based on ATP III-NCEP guidelines. Consumption frequency of fish, whole grains, dairy, fruits and vegetables was also analyzed and associated with MS prevalence. Using a healthy diet score (HDS), we described the overall diet quality and further correlated it with MS prevalence. Results: we found that lower whole grain intake was associated with greater MS prevalence (OR = 1.78; 95% CI: 1.088-2.919; p = 0.022). HDS showed better diet quality among women and in subjects with increasing age and higher educational level. A HDS < 3 points was associated with an increased risk of MS (OR HDS < 3 / HDS ≥3 = 3.69; 95% CI 1.884-7.225, p < 0.001). Conclusion: Chilean adult population exhibits a high prevalence of MS linked to a poor diet quality.

Introducción: el síndrome metabólico (SM) es un conjunto de factores de riesgo que predisponen a padecer enfermedad cardiovascular y diabetes. Una dieta poco saludable juega un rol importante en el desarrollo de esta condición. En este estudio evaluamos la prevalencia de síndrome metabólico y su asociación con la calidad de la dieta en adultos chilenos. Métodos: se analizaron los datos de 2.561 adultos mayores de 18 anos de edad incluídos en la última Encuesta Nacional de Salud (ENS 2009-2010), que contaban con informacion para el diagnostico de síndrome metabólico siguiendo los criterios de ATP III-NCEP. La frecuencia de consumo de pescado, cereales integrales, frutas, verduras y lácteos fue analizada y asociada a la presencia de SM. Por medio de un índice de dieta saludable (IDS), se evaluó la calidad global de la dieta y se correlacionó con la prevalencia de este sindrome. Resultados: un menor consumo de cereales integrales se asoció a una mayor prevalencia de síndrome metabólico (OR = 1,78; 95% IC: 1,088-2,919; p = 0,022). El IDS mostró que el consumo de alimentos tiene mejor calidad en mujeres y a mayor edad y mejor nivel educacional. Un IDS < 3 puntos se asoció con un mayor riesgo de síndrome metabólico (OR IDS < 3 / IDS ≥3 = 3,69 95% IC:1,884- 7,225, p < 0,001). Conclusión: la población adulta chilena presenta una elevada prevalencia de síndrome metabólico asociado al consumo de una alimentación de mala calidad.

Introduction: high density lipoproteins (HDL) have important cardiovascular protective effects mediated by their role in reverse cholesterol transport as well as other functional activities, including significant anti-inflammatory and antioxidant properties. It has been shown that HDL anti-inflammatory and antioxidant functions are defective in metabolically stable diabetic patients; however they have not been evaluated during a hyperglycemic crisis. Aim: to determine the antioxidant activity of HDL during a severe diabetic decompensation and to analyze whether this function is restored after resolution of the acute event. Methods: the antioxidant activity of HDL was measured in vitro by a fluorescent assay in plasma samples obtained from diabetic patients with acute metabolic decompensation at admission, recovery within the hospital and follow-up in ambulatory care. As a comparison, HDL particles from some healthy subjects were used as controls. Results: the HDL antioxidant function was significantly reduced in patients during an acute diabetic decompensation compared with the control group, and was gradually restored reaching normal values during the ambulatory follow-up. Hyperglycemic crisis also showed low plasma paraoxonase-1 activity, which increased significantly during at follow-up. Conclusion: HDL particles isolated from acute diabetic descompensated patients exhibit a significantly and reversibly low antioxidant capacity, which is probably due to a reduced paraoxonase-1 activity.

Introducción: las lipoproteínas de alta densidad (HDL) tienen un importante efecto protector cardiovascular mediado por su función durante el transporte reverso del colesterol, así como por otras actividades, incluyendo una significativa acción antiinflamatoria y antioxidante. La funcionalidad antiinflamatoria y antioxidante de las HDL está alterada en los pacientes diabéticos crónicos estables, aunque no existe mayor información en caso de una crisis hiperglicémica. Objetivo: determinar si durante un estado de descompensación diabética aguda las partículas de HDL exhiben un deterioro de su función antioxidante y si esta logra recuperarse una vez resuelto el cuadro agudo. Métodos: la actividad antioxidante de las HDL se midió mediante un ensayo de fluorescencia in vitro en muestras plasmáticas de pacientes diabéticos con descompensación aguda obtenidas tanto al ingreso, alcanzada la resolución intrahospitalaria del evento agudo, así como en un control ambulatorio post-hospitalización. Como comparación, se analizaron partículas de HDL de algunos sujetos sanos como condición control. Resultados: la actividad antioxidante de las HDL en pacientes con descompensación diabética aguda fue significativamente menor a la observada en el grupo control sano, y esta se fue recuperando progresivamente hasta normalizarse en el momento del control ambulatorio. La crisis hiperglicémica también demostró una baja actividad plasmática de la enzima antioxidante paraoxonasa-1, la cual aumentó significativamente en el control ambulatorio. Conclusión: las partículas de HDL presentes en pacientes con una descompensación diabética aguda presentan una reducción significativa y reversible de su capacidad antioxidante, probablemente como consecuencia de una alteración en la actividad de la paraoxonasa-1.

Background: Plasma high density lipoproteins (HDL) are involved in reverse cholesterol transport mediated by the scavenger receptor class B type I (SR-BI). Nicotinic acid increases HDL cholesterol levels, even though its specific impact on SR-BI dependent-cellular cholesterol transport remains unknown. Aim: To determine the effect of nicotinic acid on HDL particle functionality in cholesterol efflux and uptake mediated by SR-BI in cultured cells in hypoalphalipoproteinemic patients. Material and Methods: In a pilot study, eight patients with low HDL (≤ 40 mg/dL) were treated with extended release nicotinic acid. HDL cholesterol and phospholipid levels, HDL2 and HDL3 fractions and HDL particle sizes were measured at baseline and post-therapy. Before and after nicotinic acid treatment, HDL particles were used for cholesterol transport studies in cells transfected with SR-BI. Results: Nicotinic acid treatment raised total HDL cholesterol and phospholipids, HDL2 levels as well as HDL particle size. Nicotinic acid significantly increased HDL cholesterol efflux and uptake capacity mediated by SR-BI in cultured cells. Conclusions: Nicotinic acid therapy increases SR-BI-dependent HDL cholesterol transport in cultured cells, establishing a new cellular mechanism by which this lipid-lowering drug appears to modulate HDL metabolism in patients with hypoalphalipoproteinemia.