A ROS-Responsive DNA Nanodevice for Targeted Cytosolic siRNA Delivery in Metabolic Dysfunction-Associated Steatohepatitis.

Metabolic dysfunction-associated steatohepatitis (MASH) arises from an intricate interplay of dysregulated metabolic, inflammatory, and fibrogenic pathways, necessitating coordinated therapeutic intervention that remains inadequately achieved by current treatments. Small interfering RNA (siRNA) therapeutics offer a promising solution to this unmet need, but their potential is limited by reliance on endosomal escape, which is often associated with endosomal disruption and inflammatory signaling. Here, we introduce a steric gating strategy that programs thiol-mediated uptake for hepatocyte-selective, endosome-independent cytosolic siRNA delivery through on-demand exposure of latent disulfide moieties. To implement this strategy, we developed TRIO (Thiol-mediated siRNA delivery by Inflammation-responsive DNA Origami), a DNA origami nanodevice that reconfigures in response to reactive oxygen species to expose disulfide moieties in inflamed hepatic microenvironments. Coupling N-acetylgalactosamine (GalNAc) ligands to the nanodevice promoted hepatocyte cell-surface engagement, facilitating proximity-driven thiol-mediated uptake and efficient cytosolic delivery of siRNA payloads. Functionally, the TRIO nanodevice enabled coordinated downregulation of HSD17B13 and TAZ, two mechanistically distinct yet convergent drivers of MASH progression, thereby attenuating lipid metabolic dysregulation, inflammatory signaling, and fibrogenic activation at the cellular level. In a murine model of MASH, the nanodevice ameliorated hepatic steatosis, inflammation, and fibrosis under sustained dietary stress and expedited disease resolution upon dietary normalization. This study establishes a steric gating strategy for targeted cytosolic siRNA delivery and provides an integrated system for MASH intervention, with implications for the development of inflammation-responsive nucleic acid therapeutics.