Lithocholic acid induction of the FGF19 promoter in intestinal cells is mediated by PXR

Figure 3 Localization of the LCA/Rif/PXR responsive element in the human FGF19 promoter. A: Relative CYP3A4 and FGF19 promoter activities of LS174T cells treated with LCA (250 μmol/L) and Rif (10 μmol/L) compared to control treated cells for 24 h (P < 0.05 between LCA and Rif treatment groups and control treated groups); B: Reporter constructs were cotransfected with PXR/RXR or mock plasmids and stimulated with LCA (250 μmol/L) and Rif (10 μmol/L) as indicated for 24 h. Mock transfected and solely LCA/Rif stimulated cells were used for normalization and calculation of relative promoter induction (mean ± SD, Student’s t-test). The dotted line indicates the threshold for significant promoter induction. P < 0.05 between PXR/RXR cotransfected and LCA/Rif treated groups and mock transfected and LCA/Rif treated groups. The used reporter constructs are indicated on the x-axis.