Efeitos da suplementação de creatina no estado redox do tecido renal de ratos diabéticos induzidos por estreptozotocina

Abstract

Introduction: Creatine is a nutritional supplement that has been the subject of research in several pathologies, with a wide possibility of clinical applications. Studies have shown the effect of creatine on increasing glucose uptake by elevating the expression of GLUT4 receptors in metabolic disorders such as type II Diabetes Mellitus, however, there are no studies that report the effect of creatine on the glycemic metabolism of type I Diabetes Mellitus. Thus, this work aims to evaluate the effect of creatine supplementation in diabetic rats induced by streptozotocin. Methods: Thirty-two Wistar rats were divided into four groups: (C) animals without diabetes and without creatine supplementation (n = 8), (CCr) animals without diabetes and creatine supplementation (n = 8), (D) animals Streptozotocin-induced diabetics without supplementation (n = 8), (DCr) creatine-treated diabetic-induced diabetic animals (n = 8). Groups D and DCr received a single dose of streptozotocin (40 mg/kg i.p.). The following evaluations were performed: clinical, biochemical, as well as the analysis of redox state parameters in the renal tissue of the animals. Results and discussion: In fasting glycemia, diabetic groups presented significant hyperglycemia in comparison with the control groups, but the DCr group showed a significant improvement in relation to group D. This result corroborates previous studies that verified the same positive effect in pathological conditions that culminate in hyperglycemia. In the quantification of urea and alanine transaminase, the diabetic groups presented a significant increase in comparison with the control groups, however, the DCr group showed a significant improvement in relation to group D in both parameters. Our results of ALT and serum urea in group D can be interpreted as an increase in systemic gluconeogenesis, provable hepatic injury and protein catabolism, since urea is the main product of the ornithine cycle. The enzymatic activity of catalase, superoxide dismutase and glutathione peroxidase were significantly lower in group D compared to control groups, however, group DCr had restored activity at similar level to the control groups in all enzymes. In the quantification of the hydrogen peroxide content, group D had significantly higher levels in comparison to the control groups, however, group DCr had a similar level of restoration to the control groups in this parameter. These results converge with previous studies that observed that creatine supplementation modulates the enzymatic antioxidant activity and may be a direct antioxidant agent of reactive oxygen species. Conclusion: Creatine can improve metabolic profile in DM and restore redox state parameters in this condition. These results support creatine supplementation as a potential adjunctive therapeutic agent.