Therapeutic role of Arabic gum against nicotinamide/streptozotocin-induced diabetes and nephropathy in Wistar rats

Abstract

Chronic kidney disease is mainly caused by diabetic nephropathy and also causes a lot of suffering and death for people with diabetes, as one of the worst long-term complications. Arabic gum (AG) has been reported to have antioxidant, hypolipidemic and hypoglycemic effects. The goal of this study was to scrutinize the antioxidant and anti-inflammatory roles of AG against nicotinamide (NA)/streptozotocin (STZ)-induced diabetic nephropathy in Wistar rats. The experiment involved three groups of 18 adult male Wistar rats (six each). The normal control group received 0.9% NaCl orally for 8 weeks. The diabetic group received NA intraperitoneal injection (120 mg/kg b.w.) followed by 60 mg/kg body weight (bw) STZ in citrate buffer (pH 4.5) after 15 min. After confirming the induction of diabetes, animals received 0.9% NaCl orally for 8 weeks. The AG-treated diabetic group received 20 mg AG/kg bw/day orally for 8 weeks after diabetes induction. Diabetic rats exhibited hyperglycemia which was confirmed by increased levels of serum fasting glucose and fructosamine. Elevated serum urea, creatinine, uric acid, cystatin c, and sodium levels were noticed in the serum of diabetic rats while potassium levels were markedly reduced reflecting nephropathy. Oxidative stress was evident in the diabetic kidney, as indicated by increased malondialdehyde (MDA) and decreased reduced glutathione (GSH), glutathione peroxidase (GPx) and superoxide dismutase (SOD). AG administration ameliorated elevated fasting blood glucose and serum fructosamine levels as well as the kidney function parameters in serum. AG also attenuated oxidative stress and increased antioxidant capacity in the diabetic kidney. Immune-inflammatory mediators, such as tumor necrosis factor-alpha (TNF-α), nuclear factor kappa B (NF-κB), and tumor suppressor protein (p53) expression were significantly upregulated in diabetic rats, but AG produced a downregulation of them. Thus, AG possesses an antidiabetic effect and has a nephropreventive effect that was manifested by a decrease of urea, creatinine, uric acid, cystatin c and sodium. AG also has anti-inflammatory and antioxidant effects and minimizes histopathological alterations in the kidneys of diabetic rats. Despite these ameliorative effects, the efficacy and safety of AG as an adjunct drug for diabetic kidney disease needs to be validated by more scientific research.