Inhibition of Yes-Associated Protein by Verteporfin Ameliorates Unilateral Ureteral Obstruction-Induced Renal Tubulointerstitial Inflammation and Fibrosis

Yes-associated protein (YAP) activation after acute ischemic kidney injury might be related to interstitial fibrosis and impaired renal tubular regeneration. Verteporfin (VP) is a photosensitizer used in photodynamic therapy to treat age-related macular degeneration. In cancer cells, VP inhibits TEA domain family member (TEAD)-YAP interactions without light stimulation. The protective role of VP in unilateral ureteral obstruction (UUO)-induced renal fibrosis and related mechanisms remains unclear. In this study, we investigate the protective effects of VP on UUO-induced renal tubulointerstitial inflammation and fibrosis and its regulation of the transforming growth factor-beta 1 (TGF-beta 1)/Smad signaling pathway. We find that VP decreased the UUO-induced increase in tubular injury, inflammation, and extracellular matrix deposition in mice. VP also decreased myofibroblast activation and proliferation in UUO kidneys and NRK-49F cells by modulating Smad2 and Smad3 phosphorylation. Therefore, YAP inhibition might have beneficial effects on UUO-induced tubulointerstitial inflammation and fibrosis by regulating the TGF-beta 1/Smad signaling pathway.