Chaofeng Wu, Junjie Li, Hui Jia, Jiamin Zhao, Mengchen Qin, Hao Shi, Chang Liu, Jiajie Lin, Min Cai, Yong Gu, Bin Liu, Lei Gao
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引用次数: 0
Abstract
Background: Non-alcoholic steatohepatitis (NASH) is a rapidly progressing chronic liver disease of global significance. However, the underlying mechanisms responsible for NASH remain unknown. Indoleamine 2,3-dioxygenase 1 (IDO1) has been recognized as essential factor in immune response and metabolic regulation. Here we aimed to investigate the functions and mechanisms of the IDO1 in macrophages on hepatic lipid deposition and iron metabolism in NASH.
Methods: The effect of IDO1 in NASH was evaluated by WT and IDO1-/- mice model fed with methionine/choline-deficient (MCD) diet in vivo. Macrophages scavenger clodronate liposomes (CL) and overexpressing of IDO1 in macrophages by virus were employed as well. Lipid deposition was assessed through pathological examination and lipid droplet staining, while iron levels were measured using an iron assay kit and western blotting. Primary hepatocytes and bone marrow-derived macrophages were treated with oleic acid/palmitic acid (OA/PA) to assess IDO1 expression via Oil Red O staining and immunofluorescence staining in vitro.
Results: Pathological images demonstrated that the increase of IDO1 exacerbated lipid accumulation in the livers of mice with MCD diet, while reduction of iron accumulation was observed in the liver and the serum of MCD-fed mice. Scavenging of macrophages effectively mitigated both lipid and iron accumulation. In addition, the deficiency of IDO1 in macrophages significantly mitigated lipid accumulation and iron overload in hepatic parenchymal cells. Finally, lentivirus-mediated overexpression of IDO1 in liver macrophages exacerbated hepatic steatosis and iron deposition in NASH.
Conclusions: Our results demonstrated that effective inhibition of IDO1 expression in macrophages in NASH alleviated hepatic parenchymal cell lipid accumulation and iron deposition, which provided new insights for the future treatment of NASH.
期刊介绍:
The Journal of Gastroenterology, which is the official publication of the Japanese Society of Gastroenterology, publishes Original Articles (Alimentary Tract/Liver, Pancreas, and Biliary Tract), Review Articles, Letters to the Editors and other articles on all aspects of the field of gastroenterology. Significant contributions relating to basic research, theory, and practice are welcomed. These publications are designed to disseminate knowledge in this field to a worldwide audience, and accordingly, its editorial board has an international membership.