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Background Docosahexaenoic acid (DHA) protects against hepatic steatosis, yet its endogenous regulation in Metabolic dysfunction-associated fatty liver disease (MAFLD) remains elusive. This study investigates the clinical significance of DHA and explores Squalene epoxidase (SQLE) as its upstream regulator, delineating the SQLE-DHA-SOCS2 axis in hepatic lipid homeostasis.Methods GEO datasets and multi-omics from Sqle HepTg mice were analyzed to assess DHA levels and SQLE-regulated metabolism. In free fatty acid-induced WRL68/HepG2 models, the effects of DHA and SOCS2 modulation were evaluated. Lipid accumulation was quantified via Oil Red O/lipid droplet staining and total triglycerides and total cholesterol measurements, while CETSA and chloroquine treatment validated protein binding and stability.Results Analysis of GEO datasets revealed that hepatic DHA levels were significantly decreased in MAFLD patients and inversely correlated with the severity of steatosis, inflammation, and fibrosis. ROC curve analysis demonstrated that DHA effectively distinguished MASH patients from healthy controls (AUC=0.936). Integrated multi-omics analysis revealed that SQLE overexpression was associated with alterations in unsaturated fatty acid metabolism ( IDDF2026-ABS-0162 Figure 1). In SQLE-overexpressing hepatocytes, DHA treatment significantly ameliorated FFA-induced lipid accumulation, as confirmed by Oil Red O staining and decreased triglycerides and total cholesterol (IDDF2026-ABS-0162 Figure 2). Intersection analysis identified SOCS2 as a downstream effector. Western blot confirmed that SOCS2 protein was significantly reduced in the liver tissues of MAFLD patients and CD-HFD mice. Notably, SQLE knockout upregulated, while SQLE knock-in suppressed, hepatic SOCS2 expression. Furthermore, DHA treatment increased SOCS2 protein levels in hepatocytes (IDDF2026-ABS-0162 Figure 3). Mechanistically, CETSA confirmed that DHA directly bound to SOCS2, enhancing its stability by inhibiting autophagy-dependent degradation. Finally, SOCS2 knockdown significantly abrogated the lipid-lowering effects of DHA, whereas SOCS2 overexpression recapitulated DHA-mediated cytoprotection, as consistently validated by Oil Red O/lipid droplet staining and quantitative analysis of triglycerides and total cholesterol (IDDF2026-ABS-0162 Figure 4).Conclusions This study identifies the SQLE-DHA-SOCS2 axis as a novel link in MAFLD, where DHA serves as a MASH biomarker and rescues SQLE-induced lipid accumulation by stabilizing SOCS2, offering a promising therapeutic strategy.Abstract IDDF2026-ABS-0162 Figure 1Abstract IDDF2026-ABS-0162 Figure 2Abstract IDDF2026-ABS-0162 Figure 3Abstract IDDF2026-ABS-0162 Figure 4