Loganin attenuates diabetic nephropathy in C57BL/6J mice with diabetes induced by streptozotocin and fed with diets containing high level of advanced glycation end products

Aims: Diabetic nephropathy is the most common cause of end-stage renal disease in patients with diabetes. Advanced glycation end-products (AGES) play a prominent role in the development of diabetic nephropathy. We herein evaluated the effects of loganin on diabetic nephropathy in vivo. Main methods: We established a diabetic nephropathy model in C57BL/6 J mice with diabetes induced by streptozotocin and fed with diets containing high level of AGEs. Diabetic symptoms, renal functions, and pathohistology of pancreas and kidney were evaluated. AGE-RAGE pathway and oxidative stress parameters were determined. Key findings: The model mice exhibited characteristic symptoms of diabetes including weight loss, polydipsia, polyphagia, polyuria, elevated blood glucose levels and low serum insulin levels during the experiments. However, loganin at doses of 0.02 and 0.1 g/kg effectively improved these diabetic symptoms. Loganin reduced kidney/body weight ratio, 24 h urine protein levels, and serum levels of urea nitrogen and creatinine in diabetic mice to different degrees compared to positive controls. Moreover, loganin improved the histology of pancreas and kidney, and alleviated the structural alterations in endothelial cells, mesangial cells and podocytes in renal cortex. Finally, we found that loganin reduced AGE levels in serum and kidney and downregulated mRNA and protein expression of receptors for AGEs in kidney in diabetic mice. Loganin also reduced the levels of malondialdehyde and increased the levels of superoxide dismutase in serum and kidney. Significance: Loganin improved diabetic nephropathy in vivo associated with inhibition of AGE pathways, and could be a promising remedy for diabetic nephropathy. (C) 2015 Elsevier Inc. All rights reserved.