Visceral adiposity influences glucose and glycogen metabolism in control and hyperlipidic-fed animals / La adiposidad visceral influye en el metabolismo de la glucosa y el glucógeno en animales control y con alimentación hiperlipídica

Introduction: Evidences suggest that fat intake, visceral obesity and intracellular lipids are related to insulin impairment. Objective: The objective of the present paper was correlate visceral obesity and metabolic alterations in control (CTR) and hyperlipidic cafeteria diet (CFT) fed animals. Methods: After 6 months of diet treatment, liver and muscle of the male rats were utilized to determined glucose uptake and glycogen metabolism after administration of 0.4I U/kg insulin in vivo, and correlate the visceral adiposity to these two parameters. Results: Ample range of physiologic answers to body composition in metabolic profile of the both diets was found. No differences were found in glycemia and triacylglycerol after insulin action in both groups, however CFT group accumulated higher adiposity, mostly visceral fat, and showed lower glycogen content in the liver. We also found an inverse correlation between visceral adiposity and glucose uptake and a decrease of the glycogen synthase active form in the liver. CTR animals demonstrated an inverse correlation between glucose uptake and visceral adiposity in the muscle. Discussion and conclusion: It was observed a variability of metabolic alterations in animals which can be related to degree of accumulation of abdominal adiposity and ingestion of diet fats. Further studies will be required to clarify the reasons for the observed liver alterations in CFT and muscle alterations in CTR animals (AU)

Introducción: Las evidencias sugieren que la ingesta de grasas, obesidad visceral y lípidos intracelulares están relacionados con resistencia a la acción de la insulina. Objetivo: El objetivo del presente trabajo fue correlacionar la obesidad visceral con alteraciones metabólicas en los animales controles (CTR) y alimentados con la dieta de cafeteria hiperlipidica (CFT). Metodos: Después de 6 meses de tratamiento con dieta, el hígado y lo musculo esqueletico de los ratones se utilizaron para determinar la captación de glucosa y el metabolismo del glucógeno después de la administración de la insulina 0.4 UI/kg in vivo y correlacionar la adiposidad visceral a estos dos parámetros. Resultados: Una amplia gama de respuestas fisiológicas a la composición corporal era encontrado. No se encontraron diferencias en la glucemia y triglicéridos después de la acción de la insulina en ambos grupos, sin embargo CFT grupo acumuló mayor adiposidad, principalmente adiposidad visceral, y mostraron menor contenido de glucógeno en el hígado. También se encontró una correlación inversa entre la adiposidad visceral y la captación de glucosa y una disminución de la forma activa de la enzima glucógeno sintasa en el hígado. Animales CTR demostrado una correlación inversa entre la captación de glucosa y la adiposidad visceral en el músculo. Discusión y conclusiones: Se observó una gran variabilidad de alteraciones metabólicas en los animales que se pueden relacionados con las tasas de acumulación de la adiposidad visceral y la ingestión de grasas dietéticas. Más estudios serán necesarios para aclarar las razones de las alteraciones observadas en el hígado de los animales CFT y las alteraciones musculares en animales CTR (AU)

Metabolic effects of perinatal asphyxia in the rat cerebral cortex.

We reported previously that intrauterine asphyxia acutely affects the rat hippocampus. For this reason, the early effects of this injury were studied in the cerebral cortex, immediately after hysterectomy (acute condition) or following a recovery period at normoxia (recovery condition). Lactacidemia and glycemia were determined, as well as glycogen levels in the muscle, liver and cortex. Cortical tissue was also used to assay the ATP levels and glutamate uptake. Asphyxiated pups exhibited bluish coloring, loss of movement, sporadic gasping and hypertonia. However, the appearance of the controls and asphyxiated pups was similar at the end of the recovery period. Lactacidemia and glycemia were significantly increased by asphyxia in both the acute and recovery conditions. Concerning muscle and hepatic glycogen, the control group showed significantly higher levels than the asphyxic group in the acute condition and when compared with groups of the recovery period. In the recovery condition, the control and asphyxic groups showed similar glycogen levels. However, in the cortex, the control groups showed significantly higher glycogen levels than the asphyxic group, in both the acute and recovery conditions. In the cortical tissue, asphyxia reduced ATP levels by 70 % in the acute condition, but these levels increased significantly in asphyxic pups after the recovery period. Asphyxia did not affect glutamate transport in the cortex of both groups. Our results suggest that the cortex uses different energy resources to restore ATP after an asphyxia episode followed by a reperfusion period. This strategy could sustain the activity of essential energy-dependent mechanisms.