Lipid nanoparticle-mediated hepatocyte delivery of siRNA and silibinin in metabolic dysfunction-associated steatotic liver disease.

Lipid nanoparticle-mediated co-delivery of siRNA and small molecule holds a great potential to treat metabolic dysfunction-associated steatotic liver disease (MASLD). However, targeted delivery of therapeutics to hepatocytes remains challenging. Taking the advantage of rising low density lipoprotein receptor/very-low density lipoprotein receptor (LDLR/VLDR) levels in MASLD, the biological fate of dinonylamine-ethylene glycol chlorophosphate-1-nonanol (DNNA-COP-NA) based lipid nanoparticles (LNPs) was oriented to liver tissues via apolipoprotein E (ApoE)-LDLR/VLDLR pathway. We then adopted a three-round screening strategy to optimize the formulation with both high potency and selectivity to deliver siRNA-HIF-1α (siHIF1α) and silibinin (SLB) payloads to hepatocytes. The optimized SLB/siHIF1α-LNPs mediates great siRNA delivery and transfection of hepatocytes. In high fat diet (HFD)- and carbon tetrachloride (CCl4)-induced mouse models of MASLD, SLB/siHIF1α-LNPs enabled the silencing of hypoxia inducible factor-1α (HIF-1α), a therapeutic target primarily expressed by hepatocytes, leading to significantly reduced inflammation and liver fibrosis synergized with SLB. Moreover, it is demonstrated the hepatocyte-targeting delivery of SLB/siHIF1α-LNPs has the potential to restore the immune homeostasis by modulating the population of Tregs and cytotoxic T cells in spleen. This proof-of-concept study enable siRNA and small molecule co-delivery to hepatocytes through intrinsic variation of targeting receptors for MASLD therapy.