Fig. 7. Modulation of SIRT1 activity affects HIF-2α and fibrosis gene expression.

a NRK-49F cells were treated with CoCl₂, NMN, Sirtinol as indicated. Cell lysates were prepared for western blot analysis. HIF-1α, HIF-2α, Fibronectin, and Col I were increased by inhibition of SIRT1. GAPDH was used as a loading control. b Quantitative analysis of western blot data as shown in a. c SIRT1 interacts with and deacetylates HIF-2α. NRK-49F cells were treated with NMN, Sirtinol as indicated. Total cell lysates were prepared and subjected to co-immunoprecipitation analysis using an anti-HIF-2α antibody. The immunocomplex was analyzed by western blot. IP: immunoprecipitation. IB: immunoblot. Data are means ± SEM. ns means no significance. *P > 0.05, **P < 0.01, ***P < 0.001.