36 research outputs found

    Exercise Counterbalances Rho/ROCK2 Signaling Impairment in the Skeletal Muscle and Ameliorates Insulin Sensitivity in Obese Mice

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    Physical exercise is considered a fundamental strategy in improving insulin sensitivity and glucose uptake in skeletal muscle. However, the molecular mechanisms underlying this regulation, primarily on skeletal muscle glucose uptake, are not fully understood. Recent evidence has shown that Rho-kinase (ROCK) isoforms play a pivotal role in regulating skeletal muscle glucose uptake and systemic glucose homeostasis. The current study evaluated the effect of physical exercise on ROCK2 signaling in skeletal muscle of insulin-resistant obese animals. Physiological (ITT) and molecular analysis (immunoblotting, and RT-qPCR) were performed. The contents of RhoA and ROCK2 protein were decreased in skeletal muscle of obese mice compared to control mice but were restored to normal levels in response to physical exercise. The exercised animals also showed higher phosphorylation of insulin receptor substrate 1 (IRS1 Serine 632/635) and protein kinase B (Akt) in the skeletal muscle. However, phosphatase and tensin homolog (PTEN) and protein-tyrosine phosphatase-1B (PTP-1B), both inhibitory regulators for insulin action, were increased in obesity but decreased after exercise. The impact of ROCK2 action on muscle insulin signaling is further underscored by the fact that impaired IRS1 and Akt phosphorylation caused by palmitate in C2C12 myotubes was entirely restored by ROCK2 overexpression. These results suggest that the exercise-induced upregulation of RhoA-ROCK2 signaling in skeletal muscle is associated with increased systemic insulin sensitivity in obese mice and further implicate that muscle ROCK2 could be a potential target for treating obesity-linked metabolic disorders

    EpIG‐DB: A database of vascular epiphyte assemblages in the Neotropics

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    Vascular epiphytes are a diverse and conspicuous component of biodiversity in tropical and subtropical forests. Yet, the patterns and drivers of epiphyte assemblages are poorly studied in comparison with soil‐rooted plants. Current knowledge about diversity patterns of epiphytes mainly stems from local studies or floristic inventories, but this information has not yet been integrated to allow a better understanding of large‐scale distribution patterns. EpIG‐DB, the first database on epiphyte assemblages at the continental scale, resulted from an exhaustive compilation of published and unpublished inventory data from the Neotropics. The current version of EpIG‐DB consists of 463,196 individual epiphytes from 3,005 species, which were collected from a total of 18,148 relevĂ©s (host trees and ‘understory’ plots). EpIG‐DB reports the occurrence of ‘true’ epiphytes, hemiepiphytes and nomadic vines, including information on their cover, abundance, frequency and biomass. Most records (97%) correspond to sampled host trees, 76% of them aggregated in forest plots. The data is stored in a TURBOVEG database using the most up‐to‐date checklist of vascular epiphytes. A total of 18 additional fields were created for the standardization of associated data commonly used in epiphyte ecology (e.g. by considering different sampling methods). EpIG‐DB currently covers six major biomes across the whole latitudinal range of epiphytes in the Neotropics but welcomes data globally. This novel database provides, for the first time, unique biodiversity data on epiphytes for the Neotropics and unified guidelines for future collection of epiphyte data. EpIG‐DB will allow exploration of new ways to study the community ecology and biogeography of vascular epiphytes

    2 nd Brazilian Consensus on Chagas Disease, 2015

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    Abstract Chagas disease is a neglected chronic condition with a high burden of morbidity and mortality. It has considerable psychological, social, and economic impacts. The disease represents a significant public health issue in Brazil, with different regional patterns. This document presents the evidence that resulted in the Brazilian Consensus on Chagas Disease. The objective was to review and standardize strategies for diagnosis, treatment, prevention, and control of Chagas disease in the country, based on the available scientific evidence. The consensus is based on the articulation and strategic contribution of renowned Brazilian experts with knowledge and experience on various aspects of the disease. It is the result of a close collaboration between the Brazilian Society of Tropical Medicine and the Ministry of Health. It is hoped that this document will strengthen the development of integrated actions against Chagas disease in the country, focusing on epidemiology, management, comprehensive care (including families and communities), communication, information, education, and research

    Spatial and seasonal variation of microphytoplankton community and the correlation with environmental parameters in a hypereutrophic tropical estuary - MaranhĂŁo - Brazil

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    O estuĂĄrio do rio Bacanga apresenta um comportamento hidrodinĂąmico com fluxo de marĂ©s limitado por uma barragem. Ele Ă© considerado como um ambiente hipereutrĂłfico que recebe diariamente altas cargas de esgoto domĂ©stico sem tratamento. Este trabalho teve como objetivo avaliar a variação espaço-sazonal da comunidade fitoplanctĂŽnica e suas relaçÔes com parĂąmetros ambientais. Amostragens bimestrais foram realizadas em seis pontos fixos entre 2012 e 2013, obtendo valores dos parĂąmetros fĂ­sico-quĂ­micos e biolĂłgicos (clorofila a, composição e abundĂąncia do fitoplĂąncton) para realização das anĂĄlises estatĂ­sticas. Os resultados indicam que a comunidade fitoplanctĂŽnica Ă© representada por diatomĂĄceas, sendo Skeletonema costatum a espĂ©cie dominante responsĂĄvel por pulsos de floraçÔes em abril e junho de 2012. O predomĂ­nio dessa espĂ©cie estĂĄ relacionado aos elevados teores de silicato, pH e turbidez da ĂĄgua. Outros eventos de floraçÔes como da Euglena gracilis e Chlamydomonas sp. foram registrados em fevereiro de 2013, quando os teores de fĂłsforo total estiveram elevados e as taxas de oxigĂȘnio dissolvido foram superiores. Os dinoflagelados, cianobactĂ©rias e a diatomĂĄcea Thallassiosira sp. apresentaram ampla distribuição no perĂ­odo de estiagem e estĂŁo altamente correlacionados com a salinidade, transparĂȘncia da ĂĄgua e nutrientes. Desta forma, a distribuição da comunidade fitoplanctĂŽnica Ă© mais definida sazonalmente que espacialmenteThe Bacanga River Estuary has a hydrodynamic behavior and its tidal flow is limited by a dam. It is considered as a hypertrophic environment that receives daily high loads of domestic sewage without treatment. This study aimed to evaluate the spatial and temporal variation of phytoplankton community and its relationship with environmental parameters. Bi-monthly sampling campaigns were carried out at six fixed sites between 2012 and 2013. Physical-chemical and biological parameters were collected (chlorophyll a, phytoplankton composition and abundance) to perform the statistical correlations. The results indicate that phytoplankton community is mostly represented by diatoms, with Skeletonema costatum being the dominant species responsible for bloom in April and June of 2012. The dominance of this species is related to the high silicate concentrations, pH and turbidity. Other blooms events as well as the Euglena gracilis and Chlamydomonas sp. were recorded in February 2013, when the total phosphorus concentrations were high and the dissolved oxygen concentrations were higher. Dinoflagellates, cyanobacteria and diatom Thallassiosira sp. were widely distributed in the dry period and highly correlated with salinity, water transparency and nutrients. Hence, the distribution of phytoplankton community is more defined seasonally, rather than spatially
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