Protective effect of 2-deoxy-D-glucose on the cytotoxicity of cyclosporin A in vitro.

The present study aimed to investigate the mechanism underlying the protective effect of 2-deoxy-D-glucose (2-DG) on the cytotoxicity of cyclosporin A (CsA) in vitro using NRK-52E cells. Staining with Hoechst 33342/propidium iodide prior to flow cytometric analysis was performed to assess the rate of cellular apoptosis and necrosis induced by CsA. The expression levels of lactate dehydrogenase (LDH), caspase 3, receptor-interacting protein kinase 3 (RIP3), reactive oxygen species (ROS), glutathione (GSH) and malondialdehyde (MDA) were detected using colorimetry, ELISA, western blotting or flow cytometric analysis to determine the protective effects of 2-DG on CsA-induced cell death. The results demonstrated that 2-DG inhibited the release of LDH, the activation of caspase 3 and the generation of ROS induced by CsA, but had no effect on the expression of RIP3. Treatment with 2-DG increased the expression of GSH and decreased the expression of MDA in dose-dependent manner, and reduced the rate of the cellular apoptosis and necrosis induced by CsA. Therefore, 2-DG inhibited CsA-induced cellular apoptosis and necrosis, possibly by reducing the production of ROS. Inhibiting the activation of caspase 3 is one of the protective mechanisms of 2-DG, however, the expression of RIP3 remained unaltered following treatment with 2-DG. Whether 2-DG inhibits the CsA-induced necrosis and apoptosis by inhibiting the RIP3 signaling pathway remains to be elucidated.