Increased hepatic insulin sensitivity in mice lacking inhibitory leptin receptor signals

Leptin regulates food intake and energy expenditure by activating the long form of the leptin receptor (LepRb). Leptin also regulates glucose homeostasis by improving whole-body insulin sensitivity, but the mechanism remains undefined. Leptin action is mediated by phosphorylation of several tyrosine residues on LepRb. LepRb-Tyr985 plays an important role in the attenuation of LepRb signaling. We determined the contribution of LepRb-Tyr985-mediated signals to leptin action on insulin sensitivity using LepRb-Tyr985 mutant mice (l/l mice). Glucose tolerance and whole-body insulin-mediated glucose utilization were determined in wild-type (+/+) and l/l mice. Glucose tolerance was unaltered between female +/+ and l/l mice but enhanced in the male l/l mice. Serum insulin concentration was decreased at baseline and 15 min after a glucose injection in female l/l vs. +/+ mice (P < 0.05) but unaltered in the male l/l mice. However, basal and insulin-stimulated glucose transport in isolated soleus and extensor digitorum longus muscle was similar between +/+ and l/l mice, indicating skeletal muscle insulin sensitivity in vitro was not enhanced. Moreover, euglycemic-hyperinsulinemic clamps reveal hepatic, rather than peripheral, insulin sensitivity is enhanced in female l/l mice, whereas male l/l mice display both improved hepatic and peripheral insulin sensitivity. In conclusion, signals emanating from leptin receptor Tyr985 control hepatic insulin sensitivity in both female and male l/l mice. Lack of LepRb-Tyr985 signaling enhances whole-body insulin sensitivity partly through increased insulin action on the suppression of hepatic glucose production

A Multiple-Choice Maze-like Spatial Navigation Task for Humans Implemented in a Real-Space, Multipurpose Circular Arena.

Spatial navigation is a key aspect of human behavior and it is still not completely understood. A number of experimental approaches exist, although most of the published data in the last decades have relied on virtual maze on-screen simulation or not-completely freely moving 3D devices. Some interesting recent developments, such as circular mazes, have contributed to analyze critical aspects of freely moving human spatial navigation in real space, although dedicated protocols only allow for simple approaches. Here, we have developed both specifically designed and home-assembled hardware equipment, and a customized protocol for spatial navigation evaluation in freely moving humans in a real space circular arena. The spatial navigation protocol poses an imitation of a real-space multiple-choice path maze with cul-de-sac and instances of non-linear movement. We have compared the results of this system to those of a number of validated, both virtual and real, spatial navigation tests in a group of participants. The system composed by hardware, the test protocol, and dedicated measure analysis designed in our laboratory allows us to evaluate human spatial navigation in a complex maze with a small and portable structure, yielding a highly flexible, adaptable, and versatile access to information about the subjects’ spatial navigation abilities.P.M. was funded by a predoctoral fellowship (FPI) grant, PRE2020/093032, from the Ministerio de Ciencia e Innovación; E.C. was funded by a predoctoral fellowship (FPI) grant, BES-2017/080415, from the Ministerio de Economía y Competitividad; P.T. was funded by a predoctoral fellowship (FPU) grant, 18/00069, from the Ministerio de Universidades. This research received no other external specific funding

Next‐generation sequencing reveals that miR‐16‐5p, miR‐19a‐3p, miR‐451a, and miR‐25‐3p cargo in plasma extracellular vesicles differentiates sedentary young males from athletes

A sedentary lifestyle and Olympic participation are contrary risk factors for global mortality and incidence of cancer and cardiovascular disease. Extracellular vesicle miRNAs have been described to respond to exercise. No molecular characterization of young male sedentary people versus athletes is available; so, our aim was to identify the extracellular vesicle miRNA profile of chronically trained young endurance and resistance male athletes compared to their sedentary counterparts. A descriptive case–control design was used with 16 sedentary young men, 16 Olympic male endurance athletes, and 16 Olympic male resistance athletes. Next‐generation sequencing and RT‐qPCR and external and internal validation were performed in order to analyze extracellular vesicle miRNA profiles. Endurance and resistance athletes had significant lower levels of miR‐16‐5p, miR‐19a‐3p, and miR‐451a compared to sedentary people. Taking all together, exercise‐trained miRNA profile in extracellular vesicles provides a differential signature of athletes irrespective of the type of exercise compared to sedentary people. Besides, miR‐25‐3p levels were specifically lower in endurance athletes which defines its role as a specific responder in this type of athletes. In silico analysis of this profile suggests a role in adaptive energy metabolism in this context that needs to be experimentally validated. Therefore, this study provides for the first time basal levels of circulating miRNA in extracellular vesicles emerge as relevant players in intertissue communication in response to chronic exercise exposure in young elite male athletes

A Multiple-Choice Maze-like Spatial Navigation Task for Humans Implemented in a Real-Space, Multipurpose Circular Arena

Spatial navigation is a key aspect of human behavior and it is still not completely understood. A number of experimental approaches exist, although most of the published data in the last decades have relied on virtual maze on-screen simulation or not-completely freely moving 3D devices. Some interesting recent developments, such as circular mazes, have contributed to analyze critical aspects of freely moving human spatial navigation in real space, although dedicated protocols only allow for simple approaches. Here, we have developed both specifically designed and home-assembled hardware equipment, and a customized protocol for spatial navigation evaluation in freely moving humans in a real space circular arena. The spatial navigation protocol poses an imitation of a real-space multiple-choice path maze with cul-de-sac and instances of non-linear movement. We have compared the results of this system to those of a number of validated, both virtual and real, spatial navigation tests in a group of participants. The system composed by hardware, the test protocol, and dedicated measure analysis designed in our laboratory allows us to evaluate human spatial navigation in a complex maze with a small and portable structure, yielding a highly flexible, adaptable, and versatile access to information about the subjects’ spatial navigation abilities

Sustancias enteógenas en Ecuador y los cambios sociales actuales del pueblo shuar

Este trabajo se enmarca en los lineamientos del CONSEP, a través del proyecto “Sustancias enteógenas en Ecuador. El ritual de la ayahuasca en Zamora Chinchipe”. Esta investigación pertenece a la Quinta convocatoria interna de proyectos 2015 de la UTPL titulada “Sustancias ancestrales enteógenas en Ecuador” (PROY_CCCOM_1049).Esta investigación parte del interés por conocer y comprender el papel que puede llegar a jugar un enteógeno como la ayahuasca en el desarrollo humano, dentro de un contexto como es el ritual. Para ello realizamos una observación participante y a través de la antropología visual hemos recabado información sobre el ritual de la ayahuasca (natem) en la comunidad ecuatoriana shuar de Shaime. Además hemos observado los cambios sociales que se están produciendo en la comunidad por los efectos de la globalización. Una de las conclusiones es que el consumo de ayahuasca sobrevive a pesar del proceso de globalización y los procesos de aculturación, por muy fuertes que hayan sido.This investigation of the interest to know and understand the role it could play as an entheogen ayahuasca in human development, in a context such as the ritual. We carry out participant observation and through visual anthropology we have collected information about the ritual of ayahuasca (natem) in the Ecuadorian Shuar community Shaime. We have also observed the social changes that are occurring in the community about the effects of globalization. One conclusion is that the consumption of ayahuasca survives despite the globalization process and the processes of acculturation, however strong they have had.Universidad Técnica Particular de Loja (UTPL) PROY_CCCOM_104

Reflexiones en torno a la inclusión y grupos vulnerables

El presente libro tiene como objetivo principal presentar los retos a los que se enfrentan diferentes grupos vulnerables en su búsqueda por la inclusión socia