SGK1 Attenuates Oxidative Stress-Induced Renal Tubular Epithelial Cell Injury by Regulating Mitochondrial Function

Figure 6

Inhibition of SGK1 downregulates mitochondrial biogenesis in a GSK3β-dependent manner. HK-2 cells transfected with scramble control (null) or SGK1 shRNA (shRNA-SGK1) for 72 h were incubated with 10 μM SB21 for 1 h and then treated with H₂O₂ (250 μM) for 2 h. (a) The mitochondrial DNA (mtDNA) copy number was detected by real-time quantitative PCR analysis. (b, c) Phosphorylated GSK3β protein levels after SGK1 knockdown and (d, e) SB21 treatment are shown. (f–i) Western blot analysis was performed to elucidate the effect of SGK1 knockdown and SB21 treatment on PGC-1α, NRF-1, and TFAM protein abundance. Relative protein levels were normalized to GAPDH and total GSK3β protein levels. Data are presented as the (). and .

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