Efeitos da oxigenoterapia hiperbárica no duodeno de ratos com diabetes induzida por estreptozotocina

Abstract

Diabetes Mellitus (DM) is a metabolic disorder that results in persistent hyperglycemia resulting from a lack of insulin or failures in its action. This disorder is generally accompanied by changes in cellular redox state signaling pathways that result in inflammatory responses and subsequently in morphological damage to tissues and organs, complications associated with diabetes. Given the damage that DM causes to patients, many studies have been testing alternative therapies that can reduce these complications, such as tissue hyperoxygenation. Hyperbaric Oxygen Therapy (OHB) involves inhaling pure oxygen at high pressure. In the present study, the aim is to evaluate the effects of (OHB) on the clinical, morphological, inflammatory and oxidative parameters of the duodenum of diabetic rats. For this, 33 Wistar rats aged 60 days, weighing around 220-270g, were used. The animals were distributed into four experimental groups: control group composed of healthy animals (C), control group treated with hyperbaric oxygen therapy (C+OHB), diabetic group without treatment (D) and diabetic group treated with oxygen therapy (D+OHB). DM was induced with an intraperitoneal injection of streptozotocin 60 mg/kg. It was used inside the chamber at 2.5 absolute atmospheres (ATA) at a rate of 2 ATA/min and maintained at that pressure for 60 min. The chamber was ventilated with 100% O2 at a flow rate of 20 L/min in order to minimize CO2 accumulation for a period of 5 weeks. After euthanasia, the entire duodenum was removed, where 5 centimeters were allocated for histomorphometric, immunohistochemical and stereological analyzes and 2 centimeters for marking reactive oxygen species (ERO). It was found that OHB improved polyphagia and reversed changes in the reference volume of the duodenal lumen and absolute volume of the submucosa. It also improved the expression of Caspase-3, VEGF, SOD-1 AND GPX. From the results we conclude that hyperoxygenation in this study, despite not reducing blood glucose, had positive effects at tissue level, reducing morphological changes in volume as well as improving the expression of proteins involved in apoptosis, inflammation and oxidative stress.