Cystathionine γ-Lyase Protects Against Choline-Deficient High-Fat Diet-Induced Metabolic Dysfunction-Associated Steatotic Liver Disease Through the Cysteine-Glutathione Axis in Mice.

Abstract

AIM: Metabolic dysfunction-associated steatotic liver disease (MASLD) is a major cause of chronic liver disease, yet its pathogenesis remains incompletely understood. Oxidative stress is thought to play a key role in MASLD progression. This study aimed to investigate the role of cystathionine γ-lyase (CSE), an enzyme essential for cysteine and glutathione (GSH) biosynthesis, in MASLD development. RESULTS: Choline-deficient high-fat diet (CDHFD) feeding led to elevated aspartate aminotransferase, alanine aminotransferase, hepatic triglyceride accumulation, vacuolization, macrophage infiltration, and cell death in both genotypes, with significantly greater changes observed inmice. CDHFD also reduced hepatic CSE expression inmice and decreased cysteine/GSH levels in both genotypes, with more pronounced reductions inmice. Furthermore,deletion was associated with increased oxidized glutathione/total GSH ratios and elevated levels of 4-hydroxynonenal and malondialdehyde. Expression of glutathione synthetase and γ-glutamyl transpeptidase was increased by CDHFD inmice but blunted inmice. Furthermore, CSE deficiency exacerbated CDHFD-induced hepatic iron accumulation. INNOVATION: Our findings suggest that the CSE-cysteine-GSH axis may serve as a potential therapeutic target for MASLD, providing new intervention strategies beyond traditional approaches. This study provides new insights into the molecular mechanisms of MASLD and supports the development of antioxidant-based therapies. CONCLUSIONS: CSE deficiency exacerbates CDHFD-induced impairments of cysteine-GSH antioxidant axis, leading to hepatic oxidative stress and cell death. This indicates that CSE plays a protective role against MASLD development and progression.44, 11-23.