ITPR3 promotes liver fibrosis by damaging hepatocytes via the Ca2+/NF-B/LECT2 pathway.

Hepatocyte damage is the initial factor in liver injury. De novo expression of inositol 1,4,5-triphosphate receptor type 3 (ITPR3) typically occurs in hepatocellular carcinoma and may contribute to its pathogenesis. However, the role of de novo expression of ITPR3 by hepatocytes in the pathological processes of liver fibrosis remains unclear. Expression analyses of ITPR3 in hepatocytes were combined with an evaluation Ca2+/nuclear factor-κB (NF-κB)/leukocyte cell-derived chemotaxin 2 (LECT2) pathway and characterization of the effect of ITPR3 expression on hepatocytes damage. The effect of ITPR3 expression on liver fibrosis were evaluated in mice. ITPR3 expression was significantly increased in fibrotic mice livers and in hepatocytes induced by carbon tetrachloride (CCl4), correlating with hepatocytes apoptosis. Data from treatment with ITPR3 siRNA and an NF-κB inhibitor demonstrated that excessive Ca2+ release mediated by ITPR3 activated NF-κB, which in turn initiated LECT2 expression and induced hepatocytes apoptosis, leading to hepatic stellate cell activation-mediated liver fibrosis. These results demonstrate that de novo expression of ITPR3 may play an essential role in hepatocytes damage and liver fibrosis via Ca2+/NF-κB/LECT2 pathway. Suppression of ITPR3 may represent a novel strategy for attenuating hepatocyte damage and liver fibrosis.