The effect of intravenous c-kit + injection on the process of apoptosis in renal tissue via PI3K / Akt / GSK 3β signaling pathway and Bax, Caspase 3 and Bcl2 expression in type 2 diabetic male rats

Abstract

Stem cell-based therapy has been proposed as a novel therapeutic strategy for diabetic nephropathy. This study was designed to evaluate the effect of systemic administration of rat bone marrow-derived c-kit positive (c-kit) cells on diabetic nephropathy in male rats, focusing on PI3K/AKT/GSK-3β pathway and apoptosis as a possible therapeutic mechanism. Methods: Twenty-eight animals were randomly classifed into four groups: Control group (C), diabetic group (D), diabetic group, intravenously received 50 μl phosphatebuffered saline (PBS) containing 3×105 c-kit- cells (D+ckit-); and diabetic group, intravenously received 50 μl PBS containing 3×105 c-Kit positive cells (D+ckit+). Control and diabetic groups intravenously received 50 μl PBS. At the end of the protocols and after deep anesthesia, left kidney was isolated for apoptosis examination and the right kidney was isolated and frozen to determine the level of the PI3K, Akt, β GSK 3, Bax, Bcl2 and Caspase3 by western blot method. Results: C-kit+ cell therapy could reduce renal apoptosis, which was associated with attenuation of inflammation as indicated by decreased TNF-α and IL-6 levels in the kidney tissue. In addition, c-kit+ cells restored the levels of PI3K, pAKT, and GSK-3β proteins which decreased in diabetic condition. Furthermore, renal apoptosis was decreased following c-kit+ cell therapy, evidenced by the increased Bcl-2 and decreased Bax and Caspase-3 levels.