Dataset Information

PXR Functionally Interacts with NF-?B and AP-1 to Downregulate the Inflammation-Induced Expression of Chemokine CXCL2 in Mice.

ABSTRACT: Pregnane X receptor (PXR) is a liver-enriched xenobiotic-responsive transcription factor. Although recent studies suggest that PXR shows anti-inflammatory effects by suppressing nuclear factor kappa B (NF-?B), the detailed mechanism remains unclear. In this study, we aimed to elucidate this mechanism. Mice were treated intraperitoneally with the PXR agonist pregnenolone 16?-carbonitrile (PCN) and/or carbon tetrachloride (CCl4). Liver injury was evaluated, and hepatic mRNA levels were determined via quantitative reverse transcription polymerase chain reaction. Reporter assays with wild-type and mutated mouse Cxcl2 promoter-containing reporter plasmids were conducted in 293T cells. Results showed that the hepatic expression of inflammation-related genes was upregulated in CCl4-treated mice, and PCN treatment repressed the induced expression of chemokine-encoding Ccl2 and Cxcl2 among the genes investigated. Consistently, PCN treatment suppressed the increased plasma transaminase activity and neutrophil infiltration in the liver. In reporter assays, tumor necrosis factor-?-induced Cxcl2 expression was suppressed by PXR. Although an NF-?B inhibitor or the mutation of an NF-?B-binding motif partly reduced PXR-dependent suppression, the mutation of both NF-?B and activator protein 1 (AP-1) sites abolished it. Consistently, AP-1-dependent gene transcription was suppressed by PXR with a construct containing AP-1 binding motifs. In conclusion, the present results suggest that PXR exerts anti-inflammatory effects by suppressing both NF-?B- and AP-1-dependent chemokine expression in mouse liver.

SUBMITTER: Okamura M

PROVIDER: S-EPMC7602528 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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PXR Functionally Interacts with NF-κB and AP-1 to Downregulate the Inflammation-Induced Expression of Chemokine CXCL2 in Mice.

Okamura Maya M Shizu Ryota R Abe Taiki T Kodama Susumu S Hosaka Takuomi T Sasaki Takamitsu T Yoshinari Kouichi K

Cells 20201015 10

Pregnane X receptor (PXR) is a liver-enriched xenobiotic-responsive transcription factor. Although recent studies suggest that PXR shows anti-inflammatory effects by suppressing nuclear factor kappa B (NF-κB), the detailed mechanism remains unclear. In this study, we aimed to elucidate this mechanism. Mice were treated intraperitoneally with the PXR agonist pregnenolone 16α-carbonitrile (PCN) and/or carbon tetrachloride (CCl<sub>4</sub>). Liver injury was evaluated, and hepatic mRNA levels were ...[more]

PMID: 33076328

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Dataset Information

PXR Functionally Interacts with NF-?B and AP-1 to Downregulate the Inflammation-Induced Expression of Chemokine CXCL2 in Mice.

Publications

PXR Functionally Interacts with NF-κB and AP-1 to Downregulate the Inflammation-Induced Expression of Chemokine CXCL2 in Mice.

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