Imbalance in mitochondrial dynamics induced by low PGC-1α expression contributes to hepatocyte EMT and liver fibrosis

• Published in: Cell death & disease Vol. 11; no. 4; p. 226
• Main Authors: Zhang, Linzhong, Zhang, Yanghao, Chang, Xinxiang, Zhang, Xiuying
• Format: Journal Article
• Language: English
• Published: England Springer Nature B.V 08.04.2020; Nature Publishing Group UK
• Subjects: Animals; Bile; Carbon tetrachloride; Cell Line; Disease Models, Animal; DNA damage; Epithelial-Mesenchymal Transition; Fibrosis; Hepatocytes - metabolism; Hepatocytes - pathology; Humans; Liver; Liver Cirrhosis - metabolism; Liver Cirrhosis - pathology; Male; Mesenchyme; Mice; Mice, Inbred C57BL; Mitochondrial DNA; Mitochondrial Dynamics; Molecular modelling; Oxidative stress; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha - biosynthesis; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha - metabolism; Reactive oxygen species; Reactive Oxygen Species - metabolism; Transcription Factors - biosynthesis; Transcription Factors - metabolism; Transfection
• ISSN: 2041-4889; 2041-4889
• DOI: 10.1038/s41419-020-2429-9

An imbalance in mitochondrial dynamics induced by oxidative stress may lead to hepatocyte epithelial mesenchymal transition (EMT) and liver fibrosis. However, the underlying molecular mechanisms have not been fully elucidated. This study investigated the role of mitochondrial dynamics in hepatocyte EMT and liver fibrosis using an in vitro human (L-02 cells, hepatic cell line) and an in vivo mouse model of liver fibrosis. Findings showed that oxidative stress-induced mitochondrial DNA damage was associated with abnormal mitochondrial fission and hepatocyte EMT. The reactive oxygen species (ROS) scavengers apocynin and mito-tempo effectively attenuated carbon tetrachloride (CCl )-induced abnormal mitochondrial fission and liver fibrosis. Restoring mitochondrial biogenesis attenuated hepatocyte EMT. Oxidative stress-induced abnormal hepatocyte mitochondrial fission events by a mechanism that involved the down regulation of PGC-1α. PGC-1α knockout mice challenged with CCl had increased abnormal mitochondrial fission and more severe liver fibrosis than wild type mice. These results indicate that PGC-1α has a protective role in oxidative stress-induced-hepatocyte EMT and liver fibrosis.