Islet transplantation restores the damage of glomerulus filtration membrane in a rat model of streptozotocin-induced diabetic nephropathy.

Objective: To evaluate the effects on filtration membrane of glomerulus after islet transplantation in a rat model of streptozotocin-induced diabetic nephropathy. Methods: The experimental case-control study was conducted at Wenzhou Medical University, Wenzhou, China from January to May 2015, and comprised male Sprague Dawley rats obtained from the Laboratory Animal Centre of Wenzhou Medical University. The rats were intraperitoneally injected with streptozotocin to induce diabetic nephropathy. Diabetic rats were divided into two groups; the islets group received islets transplantation under the kidney capsule; and the diabetic nephropathy (DN) group consisted of untreated diabetic nephropathy rats. The control group consisted of non-diabetic rats. Islets were surgically transplanted under the kidney capsule. Kidney function and blood glucose were measured and pathological changes in the kidney were observed by electron microscope, while the expressions of Wilms' tumour-1, caspase-3 and transforming growth factor-beta 1 were tested by immunohistochemical method and Western blot analysis. Results: Each of the three groups had 6 rats each with body weights ranging from 180g to 220g. Reduced urinary protein excretion and alleviated damage of podocytes and glomerular basement membrane were seen in the islet transplanted rats. The alleviation of podocyte damage was related to alteration in the synthesis of caspase-3, transforming growth factor-beta 1, and Wilms' tumour-1 protein in the glomerulus. Conclusion: Diabetic nephropathy rats after islet transplantation can ameliorate the damage of podocytes and basement membrane by inhibiting the pathway of transforming growth factor-beta 1.