SRC-3 is required for CAR-regulated hepatocyte proliferation and drug metabolism

JOURNAL OF HEPATOLOGY

卷:56

Article

Chen, Tenghui¹  Chen, Qiang¹  Xu, Yixiang^2,3  Zhou, Qiling¹  Zhu, Jingwei¹  Zhang, Hao^4,5  Wu, Qiao¹  Xu, Jianming^2,3  Yu, Chundong¹ 

[1] Xiamen Univ, Sch Life Sci, State Key Lab Cellular Stress Biol, Xiamen 361005, Fujian, Peoples R China

[2] Baylor Coll Med, Dept Mol & Cellular Biol, Houston, TX 77030 USA

[3] Texas A&M Hlth Sci Ctr, Inst Biosci & Technol, Houston, TX 77030 USA

[4] Shantou Univ, Canc Res Ctr, Coll Med, Shantou 515041, Guangdong, Peoples R China

[5] Shantou Univ, Coll Med, Canc Hosp, Dept Integrat Chinese & Western Med, Shantou 515041, Guangdong, Peoples R China

关键词: SRC-3;    CAR;    Hepatocyte proliferation;    Drug metabolism;   

DOI  :  10.1016/j.jhep.2011.07.015

来源: Elsevier

【 摘 要 】

Background & Aims: Nuclear receptors such as pregnane X receptor and constitutive androstane receptor (CAR) are important regulators of drug-metabolizing systems such as P450 enzymes and modulate xenobiotic metabolism as well as hepatocellular proliferation. Binding of CAR to NR response elements alone is not sufficient to activate gene expression. Here, we investigate the role of steroid receptor co-activator (SRC) family members in CAR-mediated hepatocyte proliferation and drug metabolism. Methods: The role of SRCs in CAR activation was assessed in cell-based transfection assays and protein-protein interaction assays. The in vivo role of SRCs in CAR-mediated hepatocyte proliferation and drug metabolism was examined by using mice deficient in SRCs. Results: SRC-3 displayed the highest co-activating activity to CAR compared with SRC-1 and SRC-2 in a cell-based reporter assay. Knockout of SRC-3 in mice attenuated hepatic hyperplasia induced by a CAR agonist 1,4-bis-[2-(3,5-dichloropyridyloxy)] benzene (TCPOBOP), which was associated with a reduced expression of c-Myc and Foxm-1. In contrast, knockout of SRC-1 or SRC-2 in mice did not affect TCPOBOP-induced hepatic hyperplasia. SRC-3-deficient mice were hypersensitive to zoxazolamine-induced paralysis, but were resistant to acetaminophen hepatotoxicity induced by TCPOBOP, whereas mutant mice deficient in SRC-1 or SRC-2 exhibited severe acetaminophen hepatotoxicity similar to wild-type controls. Accordingly, deficiency in SRC-3, but not SRC-1 or SRC-2, resulted in a reduced CAR-mediated expression of drug metabolism-related genes in the liver. Conclusions: Our study demonstrates that SRC-3 is the predominant transcriptional co-activator among the three SRC family members for CAR activation to promote hepatocyte proliferation and drug metabolism. (C) 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

【 授权许可】

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