Hepatoprotective drug screening identifies daclatasvir, a promising therapeutic candidate for MASLD by targeting PLIN2.

Metabolic dysfunction-associated steatohepatitis (MASH) has become a global health challenge with limited therapeutic strategy. Here, this study aims to identify promising drug candidates for MASH and clarify its pharmacological mechanism. By extensive screening of FDA-approved hepatoprotective medicines using a PA/OA-stimulated hepatocytes model, we identified daclatasvir showing potent anti-MASH capacity against hepatic steatosis deposition and inflammatory response. The hepatoprotective benefits of daclatasvir were further validated in MASH mouse models, induced by a high-fat high-cholesterol (HFHC) diet for 16 weeks or a methionine-choline-deficient (MCD) diet for 4 weeks, as supported by markedly improved histopathological characteristics, serum biochemical level, and transcriptomic analyses. Using the molecular docking assay followed by isothermal titration calorimetry confirmation, we identified that daclatasvir functions as a new perilipin-2 (PLIN2) inhibitor by interrupting its stability. In specific, PLIN2 subjected to MARCH6-mediated protein degradation in a K11-type ubiquitination. Daclatasvir can directly bind to PLIN2 and enhance its interaction with MARCH6, leading to markedly strengthened PLIN2 ubiquitinational degradation and the subsequent decline in lipid droplet disintegration and lipotoxicity. The specific mutation at the binding amino acid sites of PLIN2 with daclatasvir largely abolished the anti-MASH benefit of daclatasvir. In conclusion, the findings of our study for the first time identified the anti-HCV drug daclatasvir as a novel and potent PLIN2 protein degradant for protection against MASH.