Cyanidin-3-O-galactoside Attenuates Metabolic Dysfunction-associated Steatotic Liver Disease by Modulating the CCL3-FABP4 Axis.

Metabolic Dysfunction-associated Steatotic Liver Disease (MASLD) is a common liver disease associated with metabolic dysfunction, and there is a lack of effective prophylactic interventions. Cyanidin-3-O-galactoside (C3G) has potential anti-inflammatory and lipid metabolism regulating activities. C57BL/6J mice were induced with high-fat diet (HFD) to establish MASLD model. Low and high dose C3G and tea polyphenols (TP) were given for 2 weeks advance. C-C motif chemokine 3 (CCL3) knockout mice were utilized to verify the key role of CCL3. C3G dose-dependently alleviated HFD-induced weight gain, liver index elevation, and hepatic steatosis. Serum levels of TC, TG, AST, and ALT were significantly reduced following C3G intervention. Two-sample Mendelian randomization (MR) identified a significant causal association between genetically predicted CCL3 elevation and increased MASLD risk. Molecular docking and molecular dynamics simulations confirmed that C3G stably binds to CCL3. C3G could down regulate the protein expression of CCL3 and fatty acid-binding protein 4 (FABP4) in liver, while attenuating macrophage infiltration and inflammatory. In addition, CCL3 deletion could simulate the intervention effect of C3G, significantly alleviate hepatic steatosis and metabolic disorders. And MR analysis and in vivo validation revealed that CCL3 serves as a positive regulator of FABP4. Collectively, C3G modulates the expression of CCL3 and is associated with the regulation of downstream FABP4, potentially contributing to the alleviation of hepatic lipid accumulation and macrophage-mediated inflammatory infiltration. These findings provide a theoretical reference for the potential role of C3G in influencing the hepatic immune-metabolic microenvironment in MASLD.