When tamoxifen is used as the substrate metabolized by UGT1A4 in HLMs, Gitogenin exhibits potent inhibition of tamoxifen, with an
IC
50
value of 6.13 µM. Similarly, for midazolam as the substrate of UGT1A4, the
IC
50
value is 5.7 µM. In addition, when olanzapine is used as a substrate of UGT1A4, the
IC
50
value is determined as 6.0 µM. Finally, we also evaluats Gitogenin for asenapine glucuronidation mediated by UGT1A4, and similar inhibition effect is observed, with an
IC
50
value of 22.0 µM.
Stimulation of growth hormone release is investigated on rat pituitary cells in vitro. Gitogenin (20 μg/mL) shows rat growth-hormone (rGH) release stimulating activities (26.1 ng/mL).
