TABLE 4

Structures of compounds that modulate UGT1A1 enzyme activity in vitro


Compound

Structure

In Vitro IC50a

Reference
Tangeretin Embedded Image 1 Williams et al. (2002)
Silybin Embedded Image 1b Goosen et al. (2004)
Chrysin Embedded Image <10 Williams et al. (2002)
Nobiletin Embedded Image >10 Williams et al. (2002)
Bilirubin Embedded Image <30 Williams et al. (2002)
17α-Ethinylestradiol
Embedded Image
Stimulation
Williams et al. (2002)
  • a Pooled human liver microsomes using estradiol 3-glucuronidation as a marker for UGT1A1 activity (Williams et al., 2002) unless indicated

  • b Recombinant UGT1A1 using HFC as substrate (Goosen et al., 2004). Ethinylestradiol stimulation of estradiol 3-glucuronidation was maximal (180% of control activity) at the lowest tested ethinylestradiol concentration (5 μM)