Avaliação do efeito do extrato metanólico de Allium cepa L. e S-metilcisteína em rim de ratos diabéticos induzidos por estreptozotocina

Abstract

Type 1 diabetes mellitus (DM1) is an autoimmune disease that results from the destruction of pancreatic β cells, lack of insulin secretion and, consequently, hyperglycemia. Diabetic nephropathy (DN) is one of the most important microvascular complications of DM and results in end-stage kidney disease. The extract of Allium cepa L. (EAC) and S-methylcysteine ​​sulfoxide (SMCS) have been studied in organs targeted by DM complications, such as pancreas, liver and intestine, but have not yet been investigated in diabetic nephropathy. Therefore, this study aimed to evaluate the preclinical, biochemical and morphological changes in the kidney of diabetic rats treated with EAC or SMCS. 35 Wistar rats (Rattus norvegicus) were used, divided into 4 groups: CONT: control group (n = 8); DM1: streptozotocin-induced diabetic group (STZ) (n = 7); DM1-EAC: diabetic group induced by STZ treated with EAC (n = 9); DM1-SMCS: diabetic rats induced by STZ treated with SMCS (n = 8). Diabetes was induced by STZ (40 mg / kg intraperitoneally) and treatment with EAC (400mg / kg) or SMCS (200mg / kg) was administered by gavage daily for 30 consecutive days one week after the induction of DM (CEUA- UFRN N.012.018 / 2017). After euthanasia the kidneys were extracted, weighed and fixed for histological processing with Hematoxylin - eosin (HE) or Schiff Periodic Acid (PAS) staining followed by histopathological and morphometric analysis, using parameters such as: Hyaline bodies, glomerular diameter and Bowman space . Interventions with EAC and SMCS were able to significantly attenuate fasting glycemia (p <0.05), polyphagia (p <0.05) and renal hypertrophy (p <0.05) of diabetic rats in relation to the group DM1. In the histomorphometric analysis, both treatments reduced the precipitates of hyaline bodies (CH) in the renal tubules (p <0.01) and the Bowman space in the glomerular corpuscle (p <0.05) when compared to the DM1 group. In view of this, therapeutic intervention, with natural products studied here, EAC and SMCS, were effective in improving harmful morphological effects on renal tissue in experimental diabetes, suggesting that these compounds may be promising candidates in the alternative or adjunctive treatment of DM.