Nelumbo nucifera leaves extract attenuate the pathological progression of diabetic nephropathy in high-fat diet-fed and streptozotocin-induced diabetic rats

• Published in: Yàowu shi͡p︡in fenxi 2019-07, Vol.27 (3), p.736-748
• Main Authors: Chen, Huan-Wei, Yang, Mon-Yuan, Hung, Tung-Wei, Chang, Yun-Ching, Wang, Chau-Jong
• Format: Article
• Language: English
• Subjects: Anticancer properties; Antidiabetics; Antioxidant enzyme; Antioxidants; Blood; Blood glucose; Body weight; Bowman's capsule; Catalase; Creatinine; Deoxyguanosine; Diabetes; Diabetes mellitus; Diabetes mellitus (non-insulin dependent); Diabetic nephropathy; Diet; Enzymatic activity; Flavonoids; Free radicals; Glucose; Glutathione; Glutathione peroxidase; High fat diet; Hyperglycemia; Injury prevention; Insulin; Insulin resistance; Kidneys; Kinases; Lipids; Lotus (Nelumbo nucifera) leaves; Malondialdehyde; Medical research; Mesangial cells; Metabolism; Metabolites; Microvasculature; Nelumbo nucifera; Nephropathy; Nitrogen; Original; Oxidative stress; Peroxidase; Peroxide; Plant extracts; Prevention; Quercetin; Reactive oxygen species (ROS); Renal failure; Staining; Streptozocin; Studies; Superoxide dismutase; Urea
• ISSN: 1021-9498; 2224-6614
• DOI: 10.1016/j.jfda.2018.12.009

Diabetic nephropathy is not only a common and severe microvascular complication of diabetes mellitus but also the leading cause of renal failure. Lotus (Nelumbo nucifera) possesses antioxidative and anticancer properties. The present study aimed to investigate the antidiabetic and renoprotective effects of N. nucifera leaf extract (NLE) in a rat model of type 2 diabetic mellitus. Male Sprague–Dawley rats with type 2 diabetes induced by a high-fat diet (HFD)/streptozotocin (STZ) were treated with NLE at dosages of 0.5% and 1% (w/w) daily for 6 weeks. At the end of the experimental period, body weight, serum glucose levels, insulin levels, and kidney function were assessed. Furthermore, antioxidant enzyme and lipid peroxide levels were determined in the kidney, and histopathological examination was performed using hematoxylin and eosin staining, periodic acid Schiff staining, and Masson trichrome staining. To shed light on the molecular mechanism underlying the functioning of NLE, mouse glomerular mesangial cells (MES-13) treated with high glucose (HG, 25 mM glucose) were chosen as a model for an examination of the signal transduction pathway of NLE. The results revealed that NLE improved diabetic kidney injury by reducing blood glucose, serum creatinine, and blood urea nitrogen levels and enhanced antioxidant enzyme activities in kidney tissue. Treatment with NLE significantly reduced the malondialdehyde and 8-hydroxy-2-deoxyguanosine levels and increased serum insulin levels; expression of renal superoxide dismutase, catalase, and glutathione peroxidase activities; and glutathione content. Histological studies have also demonstrated that NLE treatment inhibited the dilation of Bowman's capsule, which confirmed its renoprotective action in diabetes. In addition, treatment with NLE and its major component quercetin 3-glucuronide attenuated 25 mM HG-induced suppressed nuclear factor erythroid 2-related factor 2 and antioxidant enzyme expression in MES-13 cells. Collectively, these findings indicate that NLE may have antidiabetic and renoprotective effects against HFD/STZ-induced diabetes, at least in part, through antioxidative pathways. [Display omitted] •The protective mechanism of NLE treatment to renal tissue in type 2 diabetic rats.•Treatment with NLE improved glycemic status and renal functions in rats.•NLE down-regulated the expression of 8-OHdG and up-regulated expression of Nrf2.•NLE protected renal tissues and MES-13 cells from oxidative stress.•NLE