Ginsenoside Rb1-based dual-functional liposomes for enhanced siRNA delivery and synergistic anti-fibrotic therapy of hepatic fibrosis

Despite the high nucleic acid loading capacity, cationic liposomes (CLs) are facing challenges of insufficient nucleic acid drug release. Ginsenosides, natural product with a steroidal structure similar with cholesterol, not only have the potential to replace cholesterol in modulating the mobility of phospholipid bilayer and the release of nucleic acid drugs, but also exhibit therapeutic activities such as anti-fibrosis capacity. In this study, we screened potential ginsenosides and developed an efficient siRNA delivery ginsenoside liposome by replacing cholesterol with preferred ginsenoside Rb1, aiming for enhanced hepatic fibrosis treatment. To further enhance the targeted internalization to the activated hepatic stellate cells, ginsenoside liposomes were further modified with targeting cell penetrating peptide R8-dGR. Compared with cholesterol liposomes, the optimized Rb1 liposomes effectively enhanced the cellular internalization and gene silencing efficiency using Yes-associated protein (YAP) as a target. Mechanism studies reveal that the replacement of cholesterol with ginsenoside Rb1 allows membrane perturbation upon insertion into the phospholipid bilayer, leading to enhanced cell membrane fusion and lysosomal release of siRNA, which may account for enhanced cell internalization and gene silencing. Combined with the internal antifibrotic activity of ginsenoside and the downregulation of YAP, the functionalized liposome inhibited hepatic stellate cell activation and reversed abnormal extracellular matrix deposition, leading to enhanced anti-hepatic fibrosis activity both in vitro and in vivo. Owing to the transfection-promoting effect and pharmacological activity of ginsenoside Rb1, the ginsenoside liposome represents an efficient siRNA delivery approach for the treatment of hepatic fibrosis.