Débora Ribeiro Orlando

Adaptation to physical training in rats orally supplemented with glycerol.

We evaluated training adaptation and physical performance parameters in rats orally supplemented with glycerol, glucose, or saline, and submitted to moderate aerobic exercise. Thirty male rats were trained for 6 weeks and administered the supplements during the last 4 weeks of the experiment. Animals were distributed in a completely randomized factorial 2 × 3 design (with or without exercise and 3 substrates). Data were subjected to analysis of variance (ANOVA) and means were compared using the Student-Newmann-Keuls test at 5%. Among the trained animals, none of the substances caused differences in the percentages of protein, fat, or water content in the carcass. Compared with the sedentary animals, the trained animals supplemented with saline and glucose showed a higher protein percentage in the carcass. The relative mass of the heart and adrenal glands was higher in the trained animals. Glycerol improved the protein content in non-trained animals and increased the relative adrenal mass in both groups. Glycerol reduced the variation in levels of lactate and aspartate aminotransferase (AST) during the last exercise session. There was no difference between groups regarding the relative mass of the thymus and gastrocnemius or with the diameter of muscle fibers or the neutrophil-lymphocyte ratio. Supplementation with glycerol was efficient at attenuating variation in AST and lactate levels during exercise.

Exercise and Beta-Glucan Consumption (Saccharomyces cerevisiae) Improve the Metabolic Profile and Reduce the Atherogenic Index in Type 2 Diabetic Rats (HFD/STZ)

Physical activity and the ingestion of dietary fiber are non-drug alternatives commonly used as adjuvants to glycemic control in diabetic individuals. Among these fibers, we can highlight beta-glucans. However, few studies have compared isolated and synergic effects of physical exercise and beta-glucan ingestion, especially in type 2 diabetic rats. Therefore, we evaluated the effects beta-glucan (Saccharomyces cerevisiae) consumption, associated or not to exercise, on metabolic parameters of diabetic Wistar rats. The diabetes mellitus (DM) was induced by high-fat diet (HFD) associated with a low dose of streptozotocin (STZ—35 mg/kg). Trained groups were submitted to eight weeks of exercise in aquatic environment. In the last 28 days of experiment, animals received 30 mg/kg/day of beta-glucan by gavage. Isolated use of beta-glucan decreased glucose levels in fasting, Glycated hemoglobin (HbA1c), triglycerides (TAG), total cholesterol (TC), low-density lipoprotein (LDL-C), the atherogenic index of plasma. Exercise alone also decreased blood glucose levels, HbA1c, and renal lesions. An additive effect for reducing the atherogenic index of plasma and renal lesions was observed when both treatments were combined. It was concluded that both beta-glucan and exercise improved metabolic parameters in type 2 (HFD/STZ) diabetic rats.

Influence of training in the dark or light phase on physiologic and metabolic parameters of Wistar rats submitted to aerobic exercise

Light and dark phase training may influences rodents’ physiologic parameters because these animals have nocturnal habits. Thus, we verify the effects of the training in different photoperiods on metabolism and corporal composition of rats. Eighteen rats were divided into three groups – G1: non-trained; G2: trained in the light phase; G3: trained in the dark phase. Rats were allowed to swim for 60 min, five times per week during six weeks. Trained animals presented a smaller weight gain and fat percentage in carcass. Rats of G3 increased gastrocnemius relative weight. The adipocyte diameter of G3 rats was smaller than the other groups. The levels of the total cholesterol, low-density proteins, and triacylglycerols were decreased in animals of G2 while the glycemia was increased. Training in light phase provided more alterations in the blood biochemical profile while the training in the dark increased the gastrocnemius weight and decreased the diameter of the adipocyte.

Mechanisms involved in glycemic control promoted by exercise in diabetics

INTRODUCTION Diabetes mellitus is a metabolic disease characterized by high glycemic levels for long periods. This disease has a high prevalence in the world population, being currently observed an increase in its incidence. This fact is mainly due to the sedentary lifestyle and hypercaloric diets. Non-pharmacological interventions for glycemic control include exercise, which promotes changes in skeletal muscle and adipocytes. Thus, increased glucose uptake by skeletal muscle and decreased insulin resistance through modulating adipocytes are the main factors that improve glycemic control against diabetes. CONCLUSION It was sought to elucidate mechanisms involved in the improvement of glycemic control in diabetics in front of the exercise.

Effects of β-Glucans Ingestion on Alveolar Bone Loss, Intestinal Morphology, Systemic Inflammatory Profile, and Pancreatic β-Cell Function in Rats with Periodontitis and Diabetes

This study aimed to evaluate the effects of β-glucan ingestion (Saccharomyces cerevisiae) on the plasmatic levels of tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10), alveolar bone loss, and pancreatic β-cell function (HOMA-BF) in diabetic rats with periodontal disease (PD). Besides, intestinal morphology was determined by the villus/crypt ratio. A total of 48 Wistar rats weighing 203 ± 18 g were used. Diabetes was induced by the intraperitoneal injection of streptozotocin (80 mg/kg) and periodontal inflammation, by ligature. The design was completely randomized in a factorial scheme 2 × 2 × 2 (diabetic or not, with or without periodontitis, and ingesting β-glucan or not). The animals received β-glucan by gavage for 28 days. Alveolar bone loss was determined by scanning electron microscopy (distance between the cementoenamel junction and alveolar bone crest) and histometric analysis (bone area between tooth roots). β-glucan reduced plasmatic levels of TNF-α in diabetic animals with PD and of IL-10 in animals with PD (p < 0.05). β-glucan reduced bone loss in animals with PD (p < 0.05). In diabetic animals, β-glucan improved β-cell function (p < 0.05). Diabetic animals had a higher villus/crypt ratio (p < 0.05). In conclusion, β-glucan ingestion reduced the systemic inflammatory profile, prevented alveolar bone loss, and improved β-cell function in diabetic animals with PD.