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P53-mediated regulation of bile acid disposition attenuates cholic acid-induced cholestasis in mice.

ABSTRACT:

Background and purpose

The tumour suppressor p53 is traditionally recognized as a surveillance molecule to preserve genome integrity. Recent studies have demonstrated that it contributes to metabolic diseases. Here, we investigated the role of p53 in the regulation of bile acid disposition and cholestasis.

Experimental approach

The bile acid disposition-related gene expression profile affected by p53 activation was assessed in mouse primary hepatocytes with p53 depletion and in Trp53-null mice. Dual luciferase reporter assay was used to detect the transcriptional activities of target genes. Anticholestatic effects of p53 activator doxorubicin were investigated in a 0.5% cholic acid-fed mouse model of cholestasis. Changes in bile acids were evaluated using metabolomics analysis.

Key results

Doxorubicin-mediated p53 activation induced Cyp2b10, Sult2a1 and Abcc2/3/4 expression in mice in vitro and in vivo. ABCC3 and CYP2B6 (human orthologue of Cyp2b10) were identified as direct p53 target genes. Doxorubicin attenuated cholic acid-induced cholestasis in mice, as demonstrated by shrunken gall bladder, decreased serum total bile acid and total bilirubin levels and alkaline phosphatase activity. Targeted metabolomics analysis revealed that doxorubicin enhanced the excretion of bile acid metabolites from serum and liver to intestine and faeces. Up-regulation of Cyp2b10, Sult2a1 and Abcc2/3/4 expression was further confirmed in cholestatic mice. Cholic acid-induced cholestatic injury was aggravated in p53-deficient mice and levels of bile acid in intestine and faeces were decreased.

Conclusions and implications

Our findings suggest a novel role of p53 in promoting bile acid disposition and alleviating cholestatic syndrome, which provides a potential therapeutic target for cholestasis.

SUBMITTER: Chen P

PROVIDER: S-EPMC5715589 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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p53-mediated regulation of bile acid disposition attenuates cholic acid-induced cholestasis in mice.

Chen Pan P Li Dongshun D Chen Yixin Y Sun Jiahong J Fu Kaili K Guan Lihuan L Zhang Huizhen H Jiang Yiming Y Li Xi X Zeng Xuezhen X Chen Xiao X Huang Min M Bi Huichang H

British journal of pharmacology 20171022 23

<h4>Background and purpose</h4>The tumour suppressor p53 is traditionally recognized as a surveillance molecule to preserve genome integrity. Recent studies have demonstrated that it contributes to metabolic diseases. Here, we investigated the role of p53 in the regulation of bile acid disposition and cholestasis.<h4>Experimental approach</h4>The bile acid disposition-related gene expression profile affected by p53 activation was assessed in mouse primary hepatocytes with p53 depletion and in Tr ...[more]

PMID: 28910492

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