Lower expression of HNF4α and PGC1α might impair rifampicin-mediated CYP3A4 induction under conditions where PXR is overexpressed in human fetal liver cells.

@article{Takezawa2012LowerEO,
  title={Lower expression of HNF4$\alpha$ and PGC1$\alpha$ might impair rifampicin-mediated CYP3A4 induction under conditions where PXR is overexpressed in human fetal liver cells.},
  author={Takashi Takezawa and Tamihide Matsunaga and Kaori Aikawa and Katsunori Nakamura and Shigeru Ohmori},
  journal={Drug metabolism and pharmacokinetics},
  year={2012},
  volume={27 4},
  pages={
          430-8
        }
}
Pregnane X receptor (PXR) mRNA was detected in HepG2 cells by RT-PCR, but not in human fetal liver (HFL) cells. CYP3A4 was induced by rifampicin (RIF), mifepristone (RU486), clotrimazole (CTZ), and dexamethasone (DEX) in HepG2 cells, while these PXR ligands with the exception of DEX did not induce CYP3A4 mRNA expression in HFL cells. Ad-PXR infection increased mRNA levels of PXR and CYP3A4 in both cells despite the absence of PXR ligands. Similar results were observed in reporter gene assays… 

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