Mechanisms involved in anti-aging effects of guarana (Paullinia cupana) in Caenorhabditis elegans

Guarana (Paullinia cupana) is habitually ingested by people in the Amazon region and is a key ingredient in various energy drinks consumed worldwide. Extension in longevity and low prevalence of chronic age-related diseases have been associated to habitual intake of guarana. Anti-aging potential of guarana was also demonstrated in Caenorhabditis elegans; however, the mechanisms involved in its effects are not clear. Herein, we investigated the putative pathways that regulate the effects of guarana ethanolic extract (GEE) on lifespan using C. elegans. The major known longevity pathways were analyzed through mutant worms and RT-qPCR assay (DAF-2, DAF-16, SKN-1, SIR-2.1, HSF-1). The possible involvement of purinergic signaling was also investigated. This study demonstrated that GEE acts through antioxidant activity, DAF-16, HSF-1, and SKN-1 pathways, and human adenosine receptor ortholog (ADOR-1) to extend lifespan. GEE also downregulated skn-1, daf-16, sir-2.1 and hsp-16.2 in 9-day-old C. elegans, which might reflect less need to activate these protective genes due to direct antioxidant effects. Our results contribute to the comprehension of guarana effects in vivo, which might be helpful to prevent or treat aging-associated disorders, and also suggest purinergic signaling as a plausible therapeutic target for longevity studies.

Clinical practice guideline for the prevention, early detection, diagnosis, management and follow up of type 2 diabetes mellitus in adults / Guía de práctica clínica para la prevención, diagnóstico, tratamiento y seguimiento de la diabetes mellitus tipo 2 en la población mayor de 18 años

In Colombia, diabetes mellitus is a public health program for those responsible for creating and implementing strategies for prevention, diagnosis, treatment, and follow-up that are applicable at all care levels, with the objective of establishing early and sustained control of diabetes. A clinical practice guide has been developed following the broad outline of the methodological guide from the Ministry of Health and Social Welfare, with the aim of systematically gathering scientific evidence and formulating recommendations using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. The current document presents in summary form the results of this process, including the recommendations and the considerations taken into account in formulating them. In general terms, what is proposed here is a screening process using the Finnish Diabetes Risk Score questionnaire adapted to the Colombian population, which enables early diagnosis of the illness, and an algorithm for determining initial treatment that can be generalized to most patients with diabetes mellitus type 2 and that is simple to apply in a primary care context. In addition, several recommendations have been made to scale up pharmacological treatment in those patients that do not achieve the objectives or fail to maintain them during initial treatment. These recommendations also take into account the evolution of weight and the individualization of glycemic control goals for special populations. Finally, recommendations have been made for opportune detection of micro- and macrovascular complications of diabetes.

En Colombia la Diabetes Mellitus es un problema de salud pública por lo que deben generarse e implementarse estrategias de prevención, diagnóstico, tratamiento y seguimiento, aplicables en todos los niveles de atención con miras a establecer el control de la diabetes en forma temprana y sostenida. Se elaboró una guía de práctica clínica siguiendo los lineamientos de la guía metodológica del Ministerio de Salud y Protección Social para recolectar de forma sistemática la evidencia científica y formular las recomendaciones utilizando la metodología GRADE. El presente documento muestra, de forma resumida, el resultado de ese proceso, incluyendo las recomendaciones y las consideraciones tenidas en cuenta para llegar a ellas. En términos generales, se propone un proceso de tamización mediante el cuestionario FINDRISC adaptado a población Colombiana que permite llegar a un diagnóstico temprano de la enfermedad y un algoritmo para el manejo inicial que es generalizable a la gran mayoría de los pacientes con diabetes mellitus tipo 2 y que es sencillo de aplicar en atención primaria. También se hacen unas recomendaciones para escalar el tratamiento farmacológico de los pacientes que no alcanzan la meta o la pierden con el manejo inicial, teniendo en cuenta principalmente la evolución del peso y la individualización de la meta de control glucémico en poblaciones especiales. Finalmente se proponen algunas recomendaciones para la detección oportuna de las complicaciones micro y macrovasculares de la diabetes.

Involvement of glutamate and reactive oxygen species in methylmercury neurotoxicity

This review addresses the mechanisms of methylmercury (MeHg)-induced neurotoxicity, specifically examining the role of oxidative stress in mediating neuronal damage. A number of critical findings point to a central role for astrocytes in mediating MeHg-induced neurotoxicity as evidenced by the following observations: a) MeHg preferentially accumulates in astrocytes; b) MeHg specifically inhibits glutamate uptake in astrocytes; c) neuronal dysfunction is secondary to disturbances in astrocytes. The generation of reactive oxygen species (ROS) by MeHg has been observed in various experimental paradigms. For example, MeHg enhances ROS formation both in vivo (rodent cerebellum) and in vitro (isolated rat brain synaptosomes), as well as in neuronal and mixed reaggregating cell cultures. Antioxidants, including selenocompounds, can rescue astrocytes from MeHg-induced cytotoxicity by reducing ROS formation. We emphasize that oxidative stress plays a significant role in mediating MeHg-induced neurotoxic damage with active involvement of the mitochondria in this process. Furthermore, we provide a mechanistic overview on oxidative stress induced by MeHg that is triggered by a series of molecular events such as activation of various kinases, stress proteins and other immediate early genes culminating in cell damage.

Gemfibrozil en hiperlipidemias / Gemfibrozil in hyperlipidemia

En el presente estudio se evaluo el efecto de un nuevo hipolipemiante introducido en nuestro medio, el gemfibrozil. Se administro la droga en dosis de 1200 mg diarios durante tres meses a 21 pacientes, en su mayoria diabeticos no insulino-dependientes, que no habian respondido a dieta y continuaban con valores de colesterol superiores a 275 mg/dl y/o de trigliceridos superiores a 200 mg/dl. En todos los pacientes se redujo el nivel de trigliceridos (en promedio un 54.2%) y en doce se lograron valores inferiores a 175 mg/dl. Tambien se incrementaron los valores de colesterol HDL (en promedio un 30.3%) alcanzando la mayor significancia estadistica al cabo del segundo mes. El colesterol no vario significativamente pero el indice colesterol HDL/colesterol total se elevo y el incremento se mantuvo constante durante todo el periodo experimental. Los resultados confirman el efecto hipolipemiante del gemfibrozil, especificamente al normalizar la hipertrigliceridemia y elevar las HDL, ambos considerados actualmente como factores importntes en la prevencion de enfermedad coronaria especialmente en poblaciones de mayor riesgo como la diabetica.