Glucuronidation of endobiotics catalyzed by stably expressed human UGT1A8 and 1A10
Substrate | Glucuronide Formation | |
---|---|---|
UGT1A8 | UGT1A10 | |
pmol/min/mg protein | ||
Estrogens | ||
Estrone | 79 | ND |
2-Hydroxyestrone | 277 | 23 |
4-Hydroxyestrone | 1183 | 49 |
Diethylstilbestrol | 166 | ND |
17α-Ethynyl estradiol | 160 | ND |
Androgens | ||
Androsterone | ND | ND |
Testosterone | 20 | ND |
Dihydrotestosterone | 81 | 36 |
Epitestosterone | 12 | ND |
Progestins | ||
Pregnenolone | ND | ND |
17α-hydroxyprogesterone | ND | ND |
Fatty acids (0.5 mM) | ||
Butyric acid (n = 4) | ND | ND |
Caproic acid (n = 6) | ND | ND |
Caprylic acid (n = 8) | 7 | ND |
Decanoic acid (n = 10) | 19 | ND |
Dedecanoic acid (n = 12) | 12 | ND |
Tetradecanoicacid (n = 14) | ND | ND |
Bile acids (0.1 mM) | ||
Lithocholic acid | 11 | ND |
5β-etianic acid | 9 | ND |
Hyocholic acid | 39 | ND |
Hyodeoxycholic acid | 18 | ND |
Retinoids | ||
All-trans retinoic acid1-a | 35 | ND |
5,6 epoxy retinoic acid1-a | 36 | ND |
4-Hydroxyretinoic acid1-a | 67 | ND |
4-Hydroxyretinoic acid methylester | ND | ND |
Assays were performed using pH 7.4 Tris buffer at 37°C for 1.0 h and membrane preparations of HK293 cells expressing UGT1A8 or UGT1A10. The concentration of UDP-glucuronic acid was 2.0 mM and the aglycone concentrations were 0.1 mM or as otherwise indicated. Values represent the average enzymatic rates from two different experiments.
ND, not detected (limit of detection is 2.0 pmol/min/mg protein).
↵1-a Carboxyl-linked glucuronides.