Effect and mechanism of TFEB on pyroptosis in HK-2 cells induced by high glucose

Abstract

As a newly discovered way of cell death, pyroptosis has been gradually discovered in acute and chronic kidney disease. Existing studies have shown that reactive oxygen species (ROS) can induce pyroptosis and release a large number of inflammatory mediators, resulting in kidney damage. As a transcription factor, transcription factor EB(TFEB) can regulate mitochondrial energy metabolism, reduce the production of ROS, and reduce the inflammatory damage of vascular endothelial cells. In a high-glucose environment, whether TFEB can regulate oxidative stress in HK-2 cells, thereby reducing pyroptosis, has not yet been studied. This study found that in HK-2 cells, with the prolongation of high concentration glucose stimulation, the expression level of TFEB showed a trend of first increasing and then decreasing; and nuclear translocation of TFEB expression occurred within 24 h. In high-glucose environment, the expression of pyroptosis-related proteins gradually increased over time, while the expression of anti-oxidative stress proteins superoxide dismutase2(SOD2)and NAD(P)H: quinone oxidoreductase 1(NQO1) showed a trend of first increasing and then decreasing. After TFEB was transfected with overexpression plasmid, the expression levels of SOD2 and NQO1 increased significantly, and the expression of pyroptosis-related proteins decreased. Observed under a confocal microscope after Mitosox red staining, the expression of ROS in the TFEB overexpression group decreased. After down-regulating the expression of TFEB, the expression of ROS increased. The research results suggested that in HK-2 cells in the high glucose environment, TFEB may affect the pyroptosis by regulating the expression of antioxidant enzymes SOD2 and NQO1, which provides a new therapeutic idea for the treatment of diabetic nephropathy.

Keywords: Diabetic nephropathy; HK-2 cells; Pyroptosis; Reactive oxygen species; TFEB.