온라인강의

Adipocyte Death-Induced Steatotic Liver Disease: The Role of S100A8⁺ Macrophages
강사명Seonghwan Hwang 강의시간22분 강의개설일2025-12-10
온라인강의

강의소개

Objective: Both adipocytes and hepatocytes have the capacity to store fat, but the factor(s) that determine fat distribution between these cell types remain unknown. In mice fed a high-fat diet, fat initially accumulates predominantly in adipocytes, while hepatic fat accumulation mainly emerges after the onset of epididymal adipocyte death that results in elevated free fatty acids to promote lipid accumulation in hepatocytes. However, it remains unclear whether other signals following adipocyte death are required to direct and/or promote hepatocytes to store fat and subsequently trigger metabolic dysfunction-associated steatotic liver disease (MASLD). Methods and Results: Using genetically modified mouse models combined with bulk and single-cell RNA sequencing analysis, we demonstrated that visceral adipocyte death induces an accumulation of S100A8+ macrophages in the liver, which is partially induced by fatty acids. Macrophage-specific deletion of the S100a8 gene reduced hepatic fat accumulation and MASLD severity in mice. Mechanistically, S100A8+ macrophages suppress cellular communication network factor (CCN3), a negative regulator of CD36, thereby enhancing CD36 expression in hepatocytes. Conclusion: Visceral adipocyte death promotes hepatic infiltration of S100A8+ macrophages, which drive hepatocyte lipid storage and subsequently promote MASLD progression through CD36 upregulation, partially mediated by CCN3 suppression.

강사소개

Dr. Seonghwan Hwang is an Associate Professor in the College of Pharmacy at Pusan National University. He completed his undergraduate and master’s studies in pharmacy at Seoul National University and received his Ph.D. from the University of Texas Southwestern Medical Center. His research explores the pathogenic mechanisms underlying metabolic liver diseases.