Drp1-mediated mitochondrial fission promotes carbon tetrachloride-induced hepatic fibrogenesis in mice

Background: Mitochondrial dynamics is essential for the maintenance of healthy mitochondrial network. Emerging evidence suggests that mitochondrial dysfunction is closely linked to the pathogenesis of hepatic fibrogenesis following chronic liver injury. However, the role of dynamin-related protein 1 (Drp1)-mediated mitochondrial fission in the context of liver fibrosis remains unclear.

Methods and results: In this study, C57BL/6 mice were used to establish a model of liver fibrosis via oral gavage with CCl₄ treatment for 8 weeks. Furthermore, mitochondrial fission intervention experiments were achieved by the mitochondrial division inhibitor 1 (Mdivi-1). The results demonstrated that chronic CCl₄ exposure resulted in severe hepatic fibrogenesis and mitochondrial damage. By contrast, pharmacological inhibition of mitochondrial division by Mdivi-1 substantially reduced the changes of mitochondrial dynamics and finally prevented the deposition of extracellular matrix proteins. Mechanistically, excessive mitochondrial fission may activate hepatic stellate cells through RIPK1-MLKL-dependent hepatocyte death, which ultimately promotes liver fibrosis.

Conclusion: Our study imply that inhibiting Drp1-mediated mitochondrial fission attenuates CCl₄-induced liver fibrosis and may serve as a therapeutic target for retarding progression of chronic liver disease.

Mdivi-1; hepatotoxicity; liver fibrosis; mitochondrial fission.