Cannabidiol attenuates the LPS/D-Galactosamine-induced acute liver injury by inhibiting parkin-mediated ubiquitination of MFN2.

ETHNOPHARMACOLOGICAL RELEVANCE: Acute liver injury (A-LI) is a clinical syndrome that can rapidly progress to acute liver failure, resulting in high mortality and poor prognosis. Cannabis sativa L. is an important herbaceous plant that has been widely used in folk medicine since ancient times. Cannabidiol (CBD) is its most abundant non-psychoactive compound, exhibiting hepatoprotective, anti-inflammatory, and antioxidant properties. However, the protective effect of CBD against A-LI and its mechanism remain unclear.

OBJECTIVE

This study aimed to investigate the protective effects of CBD on A-LI and elucidate the underlying molecular mechanisms.

METHODS

In vivo, an A-LI mouse model was induced by LPS/D-GalN. Each group was treated with or without LPS/D-GalN or CBD. H&E staining, alanine aminotransferase (ALT), aspartate aminotransferase (AST) level assay, TUNEL staining, TEM, IF, RT-qPCR, Western blot, Co-IP and adeno-associated virus (AAV) infection were performed. In vitro, RAW264.7 cells were stimulated with LPS. CCK-8, ELISA, MMP, mitochondrial ROS assay, siRNA knockdown and plasmid overexpression were performed.

RESULTS

CBD (2.5 or 5 mg kg-1) mitigated LPS/D-GalN-induced liver damage, suppressed inflammatory cytokine expression, reduced hepatocellular apoptosis, and inhibited oxidative stress. CBD treatment increased hepatic mitofusin-2 (MFN2) protein while decreasing Parkin-MFN2 binding and MFN2 ubiquitination. In RAW264.7 cells, CBD pretreatment (2.5 or 5 μM) dose-dependently attenuated LPS-induced inflammation, apoptosis, and mitochondrial dysfunction and likewise elevated MFN2 levels while limiting its ubiquitination. MFN2 knockdown abolished CBD's protective effects, whereas MFN2 overexpression restored them. Consistently, AAV-mediated delivery of MFN2-targeting short hairpin RNA reversed the hepatoprotective action of CBD in vivo.

CONCLUSION

CBD mediates anti-inflammatory and hepatoprotective effects by inhibiting MFN2 degradation through disrupting the interaction between Parkin and MFN2. These results provide molecular evidence for application of CBD in treatment of A-LI and provide references to the drug development for A-LI.