Introduction: The choline-deficient L-amino acid defined-high fat diet (CDAA-HFD) mouse model is widely used in preclinical metabolic dysfunction-associated steatohepatitis (MASH) research. To validate the CDAA-HFD mouse, we evaluated disease progression and responsiveness to dietary and pharmacological interventions with semaglutide, lanifibranor, elafibranor, obeticholic acid (OCA), firsocostat and resmetirom.
Methods: Disease phenotyping was performed in C57BL/6J mice fed CDAA-HFD for 3-20 weeks and ranked using the MASLD Human Proximity Score (MHPS). Semaglutide, lanifibranor, elafibranor, OCA, firsocostat or resmetirom were profiled as treatment intervention for 8 weeks, starting after 6 weeks of CDAA-HFD feeding. Semaglutide and lanifibranor were further evaluated as early (preventive) therapy for 9 weeks, starting 3 weeks after CDAA-HFD diet feeding. Additionally, benefits of dietary intervention (chow reversal) for 8 weeks were characterized following 6 weeks of CDAA-HFD feeding.
Results: CDAA-HFD mice demonstrated a non-obese phenotype with fast onset and progression of MASH and fibrosis, high similarity to human MASH-fibrosis, and tumor development after 20 weeks of diet-induction. Semaglutide and lanifibranor partially reversed fibrosis when administered as prevention, but not as treatment intervention. Elafibranor was the only interventional drug therapy to improve fibrosis. In comparison, chow-reversal resulted in complete regression of steatosis with improved liver inflammation and fibrosis in CDAA-HFD mice.
Conclusion: CDAA-HFD mice recapitulate histological hallmarks of advanced MASH with progressive severe fibrosis, however, in the absence of a clinical translational obese dysmetabolic phenotype. CDAA-HFD mice are suitable for profiling drug candidates directly targeting hepatic lipid metabolism, inflammation, and fibrosis. The timing of pharmacological intervention is critical for determining anti-fibrotic drug efficacy in the model.
Keywords: CDAA-HFD mouse; Metabolic dysfunction-associated steatohepatitis; dietary intervention; disease progression; elafibranor; fibrosis; firsocostat; lanifibranor; obeticholic acid; resmetirom; semaglutide.