Liuyu Xie, Beng Wu, Yuanyuan Fan, Ye Tao, Xiaoyong Jiang, Qing Li, Huaiping Zhu, Hua Wang, Chaojie Hu
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引用次数: 0
Abstract
Background: Dysregulated fatty acid metabolism is closely linked to the development of alcohol-associated liver disease (ALD). KCs, which are resident macrophages in the liver, play a critical role in ALD pathogenesis. However, the effect of alcohol on fatty acid metabolism in KCs remains poorly understood. The current study aims to investigate fatty acid metabolism in KCs and its potential effect on ALD development.
Methods: Wild-type C57BL/6 mice were fed a Lieber-DeCarli ethanol liquid diet for 3 days. Then, the liver injury and levels of intrahepatic bacteria were assessed. Next, we investigated the effects and underlying mechanisms of ethanol exposure on fatty acid metabolism and the phagocytosis of KCs, both in vivo and in vitro. Finally, we generated KCs-specific Fasn knockout and overexpression mice to evaluate the impact of FASN on the phagocytosis of KCs and ethanol-induced liver injury.
Results: Using Bodipy493/503 to stain intracellular neutral lipids, we found significantly reduced lipid levels in KCs from mice fed an alcohol-containing diet for 3 days and in RAW264.7 macrophages exposed to ethanol. Mechanistically, alcohol exposure suppressed sterol regulatory element-binding protein 1 transcriptional activity, thereby inhibiting fatty acid synthase (FASN)-mediated de novo lipogenesis in macrophages both in vitro and in vivo. We show that genetic ablation and pharmacologic inhibition of FASN significantly impaired KC's ability to take up and eliminate bacteria. Conversely, KCs-specific Fasn overexpression reverses the impairment of macrophage phagocytosis caused by alcohol exposure. We also revealed that KCs-specific Fasn knockout augmented KCs apoptosis and exacerbated liver injury in mice fed an alcohol-containing diet for 3 days.
Conclusions: Our findings indicate the crucial role of de novo lipogenesis in maintaining effective KCs phagocytosis and suggest a therapeutic target for ALD based on fatty acid synthesis in KCs.
期刊介绍：
Hepatology Communications is a peer-reviewed, online-only, open access journal for fast dissemination of high quality basic, translational, and clinical research in hepatology. Hepatology Communications maintains high standard and rigorous peer review. Because of its open access nature, authors retain the copyright to their works, all articles are immediately available and free to read and share, and it is fully compliant with funder and institutional mandates. The journal is committed to fast publication and author satisfaction.
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