Studies show that the Th17/IL-17A axis plays an important role in the pathogenesis of kidney diseases. Previously, we also showed that IL-17A may play a role in the pathogenesis of primary nephrotic syndrome; however, the underlying mechanism(s) is unclear. The aim of this study was to explore the molecular mechanism of IL-17A-inducing podocyte injury in vitro. In this study, the NLRP3 inflammasome activation and the morphology of podocytes were detected by Western blot and immunofluorescence. The results showed that podocytes persistently expressed IL-17A receptor and that NLRP3 inflammasome in these cells was activated upon exposure to IL-17A. Also, activity of caspase-1 and secretion of IL-1β increased in the presence of IL-17A. In addition, IL-17A disrupted podocyte morphology by decreasing expression of podocin and increasing expression of desmin. Blockade of intracellular ROS or inhibition of caspase-1 prevented activation of the NLRP3 inflammasome, thereby restoring podocyte morphology. Taken together, the results suggest that IL-17A induces podocyte injury by activating the NLRP3 inflammasome and IL-1β secretion and contributes to disruption of the kidney's filtration system.
Keywords: IL-17A; IL-1β; NLRP3 inflammasome activation; ROS; podocytes.
© 2018 The Foundation for the Scandinavian Journal of Immunology.