Modulation of HIF-1α and STAT3 signaling contributes to anti-angiogenic effect of YC-1 in mice with liver fibrosis

Hypoxia has been shown to have a role in the pathogenesis of several forms of liver disease. The aim of the study was to evaluate the mechanisms of HIF-1 alpha inhibitor, YC-1, during bile duct ligation (BDL)-induced liver fibrosis in mice. Liver fibrosis was induced in mice, and YC-1 was then given intraperitoneally (50 mg/kg) once daily following 5 days. Liver injuries mice that were treated with YC-1 showed improved inflammatory response and diminished angiogenesis and hepatic fibrosis. YC-1 treatment inhibited liver neutrophil infiltration, while a decreased in TNF-alpha signaling as well as macrophage aggregation. In addition, YC-1 downregulates iNOS and COX-2 levels by inhibiting the activation of NF-kappa B and STAT3 phosphorylation by negative regulation the expression of SOCS1 and SOCS3 signaling. On the other hand, YC-1 decreased angiogenesis, as shown by the downregulation of hypoxia-inducible cascade genes, i.e. VEGF. YC-1 treatment resulted in a significant decrease in hepatic fibrogenesis, alpha-SMA abundance, and TGF-beta R1 expression as well as hypoxia were assessed using VEGFR1, vWF and HIF-1 alpha immunostaining. These results suggest that multi-targeted therapies directed against angiogenesis, hypoxia, and fibrosis. Therefore, it may be suggested that YC-1 treatment may be a novel therapeutic agent for the treatment of liver disease.