Fig. 8.

Silencing PINK1 or PARK2 increased mitochondrial ROS production and subsequently activated the NLRP3 inflammasome in contrast-treated HK-2 cells. HK-2 cells were transfected with negative control siRNA, PINK1 siRNA, or PARK2 siRNA. After transfection for 8 h, cells were pretreated with MitoTEMPO (100 μM) for 4 h and then cultured with iohexol for 72 h. (A–C) Representative images and quantification of mitochondrial ROS (MitoSOX) and 8-OHdG in HK-2 cells. Scale bar: 50 μm (MitoSOX) and 25 μm (8-OHdG). (D) Mitochondrial ROS was also assessed by MnSOD activity (U/mg protein) of HK-2 cells. (E, F) Immunoblot analysis and quantification of NLRP3, caspase-1 p20, and IL-1β p17 in SiNC, SiPINK1, and SiPARK2 cells with iohexol. (G, H). Representative images and quantification of immunofluorescence staining caspase-1 and IL-1β in HK-2cells. Scale bar: 50μm. (I–J) Immunoblot analysis and quantification of NLRP3, caspase-1 p20, and IL-1β p17 in HK-2 cells pretreated with or without MitoTEMPO, after silencing PINK1 or PARK2 in response to iohexol. Data were presented as mean ± TEM. *p < 0.05, **p < 0.01, ***p < 0.001. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)