Diammonium glycyrrhizinate ameliorates alcohol-induced liver injury by reducing oxidative stress, steatosis, and inflammation

Alcohol-induced liver injury (ALI) is a serious global health issue. Diammonium glycyrrhizinate (DG), a pharmaceutical form of glycyrrhizic acid, has been reported to have anti-inflammatory and anti-oxidative stress properties. We investigated the potential hepatoprotective effects of DG against ALI and explored the mechanisms of it. In vivo, C57BL/6J mice were used to investigate the protective effect of DG on ALI induced by chronic plus binge alcohol exposure. In vitro, AML-12 cells were applied to evaluate the role of DDX5 in the hepatic protection of DG and explore the possible mechanism of STAT1 activation regulated by DDX5. The results showed that DG significantly alleviated liver injury, inflammation, and lipid deposition in hepatocytes. It also beneficially influenced oxidative stress dysregulation. RNA-seq expression in mouse liver tissue indicated that Dead-box helicase 5 (DDX5) might be a potential target of DG. Compared with the control group, the expression of DDX5 decreased significantly in the ethanol-fed group, while DDX5 was restored in the DG treatment group. In addition, the protective effects of DG against ALI were impaired by DDX5 deficiency. DDX5 inhibited the phosphorylation of signal transducer and activator of transcription 1 (STAT1) by recruiting the protein inhibitor of activated STAT1 (PIAS1) to STAT1. The protective effect of DG against ALI associated with oxidative stress, steatosis, and inflammation was probably via regulating the DDX5/STAT1 axis.