Fig. 2.

INT-767 is a potent TGR5 agonist. A, NCI-H716 cells were stimulated with increasing concentrations of INT-767 and cAMP levels measured by TR-FRET. INT-767 induces a robust increase of cAMP (EC₅₀ = 0.68 μM). LCA and INT-777 were used as positive controls. The results show mean ± S.D. of triplicate samples from a representative experiment of 10 performed. The Z′ factor of 0.75 indicates that the assay is robust and suitable for high-throughput screening. B, HEK293T cells were transiently transfected with TGR5 or vector only, and cAMP levels were measured by TR-FRET. INT-767 induces TGR5-dependent cAMP production. The results show mean ± S.D. of triplicate samples from a representative experiment of three performed. C, transactivation assay performed in HEK293 cells transiently transfected with TGR5 or vector only and the CRE-Luc reporter plasmid. Cells transfected with vector only were stimulated with 100 μM INT-767. The results show mean ± S.D. of triplicate samples from a representative experiment of three performed. D, c-fos expression determined by quantitative RT-PCR in NCI-H716 cells treated with the indicated concentrations of test compounds for 1 h. *, p < 0.0001 versus NT, cells stimulated with medium only.