Rg1 Attenuates alcoholic hepatic damage through regulating AMP-activated protein kinase and nuclear factor erythroid 2-related factor 2 signal pathways

Rg1 has shown multiple pharmacological activities and been considered to be evaluated for hepatic protective activity, as Rg1 could modulate different pathways in various diseases. Herein we assessed its effect and potential mechanism in a newly modified ethanol model. C57BL/6 mice were fed with Lieber-DeCarli liquid diet containing ethanol or isocaloric maltose dextrin as control diet with or without Rg1. Meanwhile, bicyclol was treated as positive drug to compare the efficacy of Rg1 against alcoholic hepatotoxicity. According to our data, Rg1 indeed improved the survival rate and lowered the abnormal high levels of serum parameters. H&E and Oil Red O staining indicated that the condition of liver damage was mitigated by Rg1 administration. Furthermore, AMPK and Nrf2 pathways were all modulated at both RNA and protein levels. In accordance with these findings, Rg1 effectively protected against alcoholic liver injury, possibly by modulating metabolism, suppressing oxidative stress, and enhancing oxidant defense systems of Nrf2 pathway. In vitro, Rg1 has no cell toxicity and promotes Nrf2 translocate into nuclear. In summary, we demonstrate that Rg1 is a potent activator of Nrf2 pathway, and could therefore be applied for prevention of hepatic damage.