Ginsenoside Rk2 alleviates hepatic ischemia/reperfusion injury by enhancing AKT membrane translocation and activation.

Abstract

Hepatic ischemia-reperfusion injury (IRI) poses a significant threat to clinical outcomes and graft survival during hemorrhagic shock, hepatic resection, and liver transplantation. Current pharmacological interventions for hepatic IRI are inadequate. In this study, we identified ginsenoside Rk2 (Rk2), a rare dehydroprotopanaxadiol saponin, as a promising agent against hepatic IRI through high-throughput screening. The pharmacological effects and molecular mechanisms of Rk2 on hepatic IRI were further evaluated and elucidated in vitro and in vivo. Rk2 significantly reduced inflammation and apoptosis caused by oxygen-glucose deprivation and reperfusion in hepatocytes and dose dependently protected against hepatic I/R-induced liver injury in mice. Integrated approaches, including network pharmacology, molecular docking, transcriptome analysis, and isothermal titration calorimetry, along with experimental validation, indicated that Rk2 protects against hepatic IRI by targeting and activating the AKT (RAC serine/threonine protein kinase) signaling pathway. Pharmacological inhibition of AKT pathway or knockdown of AKT1 effectively diminished protective effects of Rk2. Rk2 directly binds to AKT1, facilitating its translocation from the cytoplasm to plasma membrane. This process markedly enhanced AKT interaction with PDPK1, promoting the activation of AKT1 and its downstream signaling. Our findings demonstrate that Rk2 protects against hepatic IRI by activating AKT signaling through direct binding to AKT1 and facilitating its membrane translocation.