Inhibition of the transient receptor potential vanilloid 3 channel attenuates carbon tetrachloride-induced hepatic fibrosis.

ABSTRACT

Transient receptor potential vanilloid 3 (TRPV3) is a member of the TRP superfamily. Previous studies have demonstrated that TRPV3 is associated with myocardial fibrosis. However, the role of TRPV3 in hepatic fibrosis and its underlying mechanisms are still unclear. This study aimed to elucidate the underlying effects of TRPV3 on hepatic fibrosis at multiple biological levels. First, immunohistochemical staining was performed to examine TRPV3 expression in human hepatic cirrhosis tissues. Then, we established a CCl4-induced hepatic fibrosis mouse model. The TRPV3 selective agonist drofenine and its inhibitor, forsythoside B, were intraperitoneally injected to investigate the relationship between TRPV3 and liver fibrosis progression. Finally, in vitro studies were performed using hepatic stellate cells (HSCs) to discover the potential molecular biological mechanisms. Immunohistochemistry revealed TRPV3 overexpression in liver cirrhosis. In the liver fibrosis groups, TRPV3 inhibitor treatment significantly reduced liver fibrosis, while TRPV3 agonist exacerbated its progression. In HSCs, knocking down TRPV3 with siRNA impaired DNA synthesis and cell proliferation and increased cell apoptosis. Furthermore, we found that knockdown of TRPV3 could reduce the lectin like oxidized lowdensity lipoprotein receptor-1 (LOX-1) protein levels. Our research suggests that lower expression or functional levels of TRPV3 can ameliorate the inflammatory response and fibrotic tissue proliferation.