Figure 8.

αKlotho upregulates autophagy and protects kidney cell against oxidative stress–induced cell injury. OK cells were treated with H₂O₂ with or without Baf (200 nM). In addition, recombinant αKlotho protein was added to examine whether αKlotho suppresses cell injury induced by H₂O₂. (A) LDH in supernatants released from OK cells was used for assessment of cell injury. (B) Protein expression of LC3-I, LC3-II, and p62 protein in OK cells. (Left panel) Representative immunoblots for LC3-I and LC3-II, p62, and β-actin protein. (Right panel) Summary of immunoblots from three independent experiments. Data are expressed as means±SDs. (C) Representative immunocytochemistry for αKlotho (blue), LC3 (green), and phalloidin (red) in OK cells. OK cells were seeded on coverslips and transfected with GFP-LC3 plasmid. After 24 hours of transfection, cells were treated with H₂O₂ and/or Baf. Vehicle (upper panel) or recombinant αKlotho protein (0.4 nM; lower panel) was added to examine whether αKlotho suppresses cell injury induced by H₂O₂ in the presence of αKlotho or vehicle for control for 24 hours. Scale bar, 20 μm. (D) Quantification of the number of GFP-LC3 punctae per cell in OK cells (100 cells analyzed per sample). Results represent as means±SDs from three independent experiments. Statistical significance was assessed by one-way ANOVA followed by Newman–Keuls test. Statistical significance was accepted when *P<0.05; **P<0.01 between two groups.