High glucose induces autophagy in podocytes

Autophagy is a cellular pathway involved in protein and organelle degradation. It is relevant to many types of cellular homeostasis and human diseases. High level of glucose is known to inflict podocyte injury, but little is reported about the relationship between high concentrations of glucose and autophagy in these cells. The present study demonstrates that high glucose promotes autophagy in podocytes. Rapamycin further enhances this effect, but 3-methyadenine inhibits it. The proautophagic effect of high glucose manifested in the form of enhanced podocyte expression of LC3-2 and beclin-1; interestingly, antioxidants such as NAC were found to inhibit high glucose-induced autophagy. High glucose induced the generation of ROS by podocytes in a time-dependent manner. High glucose also enhanced podocyte expression of MnSOD and catalase. These findings indicate that high glucose-induced autophagy is mediated through podocyte ROS generation. (C) 2013 Elsevier Inc. All rights reserved.