Estudio del efecto protector frente al estrés oxidativo en ratas diabéticas suplementadas con un sazonador obtenido a partir de residuos vitivinícolas

Abstract

Oxidative stress is well-known to play an important role in the pathogenesis of diabetes mellitus type 1 (DMT1) and also in its development. Hyperglycemia induces a pro-oxidative environment leading to the initiation and propagation of endothelial dysfunction and vascular complications characteristic of DMT1. As a consequence of the excessive levels of reactive oxygen and nitrogen species (RONS) generated, considerable structural damage to lipids and proteins in the vasculature may take place. Wine pomace is a winery by-product with recognized antioxidant properties, so wine pomace derived products might improve the antioxidant status in the microenvironment of blood vessels. Therefore, the aim of the current study was to evaluate the protection of a patented functional seasoning, obtained from wine pomace, against vascular oxidative damage and several classical symptoms associated to DMT1. Streptozotocin-induced type 1 diabetic (DB) Wistar rats and control (C) rats were supplemented with the seasoning (+S) or vehicle (water) for 4 weeks. Daily food and water intakes were registered, and blood glucose levels and body weight body weight were measured weekly. Total antioxidant capacity assessed using the ABTS method and F2-isoprostanes quantified by gas chromatography-mass spectrometry were measured in plasma collected at the end of the study. F2-Isoprostanes are widely recognized as the best biomarker of lipid peroxidation in vivo. The results showed that food and water intakes were higher in diabetic than in control rats at the beginning of the study. Supplementation with the seasoning tended to normalize both intakes, although levels observed in the control groups were not reached. Blood glucose levels tended to increase along the study in the DB group. Seasoning supplementation did not succeed to reduce blood glucose concentration significantly in the DB+S rats, but it was relatively stable during the whole experiment in this group. In the DB rats, considerable body weight loss was observed after 4 weeks, whereas the decrease in body weight was less marked in the DB+S rats. Plasma total antioxidant capacity decreased significantly only in the DB group, with the rest of groups showing similar values. Moreover, plasma levels of F2-isoprostanes were increased in the DB rats compared to the DB+S rats. In conclusion, 4-week supplementation with a seasoning derived from vinification residues tended to normalize food and water intakes, avoided a higher increase in blood glucose levels, ameliorated the weight loss, improved the redox status, and protected against lipid peroxidation in the vascular microenvironment of diabetic rats affected by DMT1.