Liver-specific delivery of MDM2 antisense oligoneucleotides counteracts diet-induced metabolic dysfunction-associated steatotic liver disease in mouse models

Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses a spectrum of pathogenic conditions ranging from steatosis, inflammation and fibrosis. This chronic metabolic disease progresses through multiple mechanisms, and the treatment options remain limited. We previously demonstrated an upregulation of hepatic murine double minute 2 (MDM2) in human subjects with MASLD, highlighting its potential role as therapeutic target. Genetic deletion of hepatic MDM2 and pharmacological inhibition of systemic MDM2 improves steatosis and fibrosis in mouse models. In this study, we developed and investigated the therapeutic potential of triantennary N-acetylgalactosamine (GalNAc)-conjugated antisense oligonucleotide targeting MDM2 (GalNAc-Mdm2ASO) in two diet-induced mouse models of MASLD: a high-fat-high-cholesterol (HFHC) diet and a choline-deficient L-amino acid-defined high-fat diet (CDAHFD). In the HFHC-induced MASLD model, GalNAc-Mdm2ASO not only alleviated liver injury, steatosis, and fibrosis but also improved obesity-related insulin resistance and hyperlipidaemia. The hepatoprotective effects of GalNAc-Mdm2ASO treatment were associated with a reduced accumulation of hepatic cholesterol and ceramide, both of which are known to trigger MASLD. In CDAHFD mouse model, GalNAc-Mdm2ASO significantly mitigated hepatic inflammation, cholesterol accumulation and fibrosis but not triglyceride accumulation. Overall, we prove hepatic inhibition of MDM2 using GalNAc-Mdm2ASO as a promising therapeutic agent for MASLD in two rodent models with distinct pathogenesis.