The influence of different types of fasting on lipid profile of volunteers from a city of Rio Grande do Sul, Brazil / A influência de diferentes tipos de jejum no perfil lipídico em voluntários de um município do Rio Grande do Sul, Brasil

ABSTRACT Introduction: Determination of lipid profile includes triglycerides (TG), total cholesterol and fractions as high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c). These parameters are valuable in the risk assessment of developing cardiovascular disease. However, some pre-analytical factors, such as the fasting state, may interfere with the results of these tests. Objective: The aim of this study was to evaluate differences on lipid profile measurements in blood samples collected at different fasting periods in men and women with or without a diagnosis of hypercholesterolemia. Methods: Fifty volunteers of both sexes, aged between 22 and 86 years, were evaluated. Sociodemographic data and two blood samples were collected, one after 12 hours fast and another during postprandial period, with subsequent measurement of total cholesterol, HDL-c, LDL-c and TG. Results: Comparing the values of the lipid profile obtained in the two collections, it was observed that the total cholesterol and HDL-c did not present significant differences among the evaluated subjects. On the other hand, LDL-c and TG showed significant higher values on postprandial samples, preferably in male group. Conclusion: These data suggest that TG and LDL-c levels are the fractions with greater susceptibility to variations when they are collected without prior fasting.

RESUMEN Introducción: La determinación del perfil lipídico incluye los triglicéridos (TG), colesterol total y fracciones del colesterol de la lipoproteína de alta densidad (HDL-c) y colesterol de la lipoproteína de baja densidad (LDL-c). Eses parámetros son muy valiosos en la evaluación del riesgo cardiovascular. Sin embargo, algunos factores preanalíticos, como el estado de ayuno, pueden interferir en los resultados de esos exámenes. Objetivo: Evaluar si hay diferencias significativas en la determinación del perfil lipídico en muestras de sangre recolectadas de hombres y mujeres con o sin diagnóstico de hipercolesterolemia. Método: Se evaluaron 50 voluntarios de ambos sexos, con edades comprendidas entre 22 y 86 años. Se recolectaron informaciones sociodemográficas y dos muestras de sangre, una con ayuno previo de 12 horas y otra posprandial, con determinación posterior de colesterol total, HDL-c, LDL-c, y TG. Resultados: Comparándose los valores obtenidos del perfil lipídico en las dos coletas, se observó que el colesterol total y el HDL-c no presentaron diferencias significativas en los sujetos evaluados. Al mismo tiempo, LDL-c y TG mostraron valores significativamente más elevados en la recolecta posprandial, preferencialmente en el grupo masculino. Conclusión: El conjunto de datos obtenidos sugiere que los niveles de TG y LDL-c son las fracciones con mayor susceptibilidad a variaciones cuando son recolectadas sin ayuno previo.

RESUMO Introdução: A determinação do perfil lipídico inclui dosagens de triglicerídeos (TG), colesterol total e frações do colesterol da lipoproteína de alta densidade (HDL-c) e do colesterol da lipoproteína de baixa densidade (LDL-c). Esses parâmetros são muito valiosos na avaliação do risco do desenvolvimento de doenças cardiovasculares. Porém, alguns fatores pré-analíticos, como o estado de jejum, podem interferir nos resultados desses exames. Objetivo: Avaliar se existem diferenças significativas nas dosagens do perfil lipídico em amostras de sangue coletadas em diferentes períodos de jejum em homens e mulheres com ou sem diagnóstico de hipercolesterolemia. Método: Foram avaliados 50 voluntários de ambos os sexos, com faixa etária entre 22 e 86 anos. Foram coletadas informações sociodemográficas e duas amostras de sangue, uma com jejum prévio de 12 horas e outra pós-prandial, com posterior dosagem de colesterol total, HDL-c, LDL-c e TG. Resultados: Ao comparar os valores obtidos do perfil lipídico nas duas coletas, observou-se que o colesterol total e o HDL-c não apresentaram diferenças significativas nos sujeitos avaliados. Por outro lado, o LDL-c e o TG expressaram valores significativamente mais elevados na coleta realizada de forma pós-prandial, preferencialmente no grupo masculino. Conclusão: O conjunto dos dados obtidos sugere que os níveis de TG e LDL-c são as frações com maior suscetibilidade a variações quando são coletadas sem jejum prévio.

Low-concentration exposure to glyphosate-based herbicide modulates the complexes of the mitochondrial respiratory chain and induces mitochondrial hyperpolarization in the Danio rerio brain.

Glyphosate (N-phosphonomethyl-glycine) (GLY) is the active ingredient of the most used herbicides in the world. GLY is applied in formulated products known as glyphosate-based herbicides (GBH), which could induce effects that are not predicted by toxicity assays with pure GLY. This herbicide is classified as organophosphorus compound, which is known to induce neurotoxic effects. Although this compound is classified as non-neurotoxic by regulatory agencies, acute exposure to GBH causes neurological symptoms in humans. However, there is no consensus in relation to neurotoxic effects of GBH. Thus, the aim of this study was to investigate the neurotoxic effects of the GBH in the zebrafish Danio rerio, focusing on acute toxicity, the activity and transcript levels of mitochondrial respiratory chain complexes, mitochondrial membrane potential, reactive species (RS) formation, and behavioral repertoire. Adult zebrafish were exposed in vivo to three concentrations of GBH Scout®, which contained GLY in formulation (fGLY) (0.065, 1.0 and 10.0 mg L-1 fGLY) for 7 d, and an in vitro assay was performed using also pure GLY. Our results show that GBH induced in zebrafish brain a decrease in cell viability, inhibited mitochondrial complex enzymatic activity, modulated gene expression related to mitochondrial complexes, induced an increase in RS production, promoted hyperpolarization of mitochondrial membrane, and induced behavioral impairments. Together, our data contributes to the knowledge of the neurotoxic effects of GBH. Mitochondrial dysfunction has been recognized as a relevant cellular response that should not be disregarded. Moreover, this study pointed to the mitochondria as an important target of GBH.

In vivo manganese exposure modulates Erk, Akt and Darpp-32 in the striatum of developing rats, and impairs their motor function.

Manganese (Mn) is an essential metal for development and metabolism. However, exposures to high Mn levels may be toxic, especially to the central nervous system (CNS). Neurotoxicity is commonly due to occupational or environmental exposures leading to Mn accumulation in the basal ganglia and a Parkinsonian-like disorder. Younger individuals are more susceptible to Mn toxicity. Moreover, early exposure may represent a risk factor for the development of neurodegenerative diseases later in life. The present study was undertaken to investigate the developmental neurotoxicity in an in vivo model of immature rats exposed to Mn (5, 10 and 20 mg/kg; i.p.) from postnatal day 8 (PN8) to PN12. Neurochemical analysis was carried out on PN14. We focused on striatal alterations in intracellular signaling pathways, oxidative stress and cell death. Moreover, motor alterations as a result of early Mn exposure (PN8-12) were evaluated later in life at 3-, 4- and 5-weeks-of-age. Mn altered in a dose-dependent manner the activity of key cell signaling elements. Specifically, Mn increased the phosphorylation of DARPP-32-Thr-34, ERK1/2 and AKT. Additionally, Mn increased reactive oxygen species (ROS) production and caspase activity, and altered mitochondrial respiratory chain complexes I and II activities. Mn (10 and 20 mg/kg) also impaired motor coordination in the 3(rd), 4(th) and 5(th) week of life. Trolox™, an antioxidant, reversed several of the Mn altered parameters, including the increased ROS production and ERK1/2 phosphorylation. However, Trolox™ failed to reverse the Mn (20 mg/kg)-induced increase in AKT phosphorylation and motor deficits. Additionally, Mn (20 mg/kg) decreased the distance, speed and grooming frequency in an open field test; Trolox™ blocked only the decrease of grooming frequency. Taken together, these results establish that short-term exposure to Mn during a specific developmental window (PN8-12) induces metabolic and neurochemical alterations in the striatum that may modulate later-life behavioral changes. Furthermore, some of the molecular and behavioral events, which are perturbed by early Mn exposure are not directly related to the production of oxidative stress.