Ginsenoside Rf protects against acetaminophen‐induced liver injury by targeting CCAR2 to activate the SIRT1‐FXR signalling pathway

BACKGROUND AND PURPOSE: Acetaminophen (paracetamol) overdose has emerged as a major cause of drug-induced liver failure, and effective clinical treatment is limited. This study investigated the effects of ginsenoside Rf, a natural product from the Chinese herbal medicine ginseng, on acetaminophen-induced liver injury (AILI) in mice. EXPERIMENTAL APPROACH: The protective effects of ginsenoside Rf against AILI were evaluated using cellular and mouse models. RNA sequencing and subsequent experimental validations were conducted to investigate the mechanisms of ginsenoside Rf against AILI. A pull-down assay was used to identify the potential targets of ginsenoside Rf. KEY RESULTS: Pretreatment with ginsenoside Rf significantly alleviated AILI. Ginsenoside Rf also inhibited acetaminophen-induced excessive oxidative stress, inflammatory response, hepatocellular apoptosis and abnormalities in bile acid metabolism. One protein, cell cycle and apoptosis regulator 2 (CCAR2), was identified as a specific target of ginsenoside Rf. By binding with CCAR2, ginsenoside Rf significantly disrupted acetaminophen overdose-induced interaction of CCAR2 with the deacetylase sirtuin 1 (SIRT1), thereby reducing farnesoid X receptor (FXR) acetylation modification. Simultaneously, ginsenoside Rf up-regulated FXR, facilitating its nuclear translocation, and transcriptionally activating its target genes required for bile acid metabolism. Liver-specific Ccar2 gene deletion attenuated acetaminophen-induced mice liver injury and abolished the hepatoprotective effects of ginsenoside Rf in AILI. CONCLUSION AND IMPLICATIONS: Collectively, these findings propose CCAR2 as a potential target to prevent AILI. Ginsenoside Rf exhibits a significant hepatoprotective effect against AILI through the CCAR2-SIRT1-FXR signalling pathway.