Table 1.
IC50 values for inhibition of cytochrome P450 enzymes in human liver microsomes by licochalcone A and extracts of G. uralensis, G. inflata and G. glabra (mean ± standard deviation).
| Enzyme | Substrate |
G. glabra IC50 (µg/mL) |
G. uralensis IC50 (µg/mL) |
G. inflata IC50 (µg/mL) |
Licochalcone A IC50 (µg/mL) |
|---|---|---|---|---|---|
| CYP1A2 | Phenacetin | 83.04 ± 16.96 | 68.25 ± 26.75 | 18.07 ± 4.14 | 12.40 ± 3.47 |
| CYP2A6 | Coumarin | >100 | >100 | >100 | >25 |
| CYP2B6 | Bupropion | 19.58 ± 1.80 | 6.51 ± 0.97 | 23.89 ± 4.55 | 17.96 ± 4.58 |
| CYP2C8 | Amodiaquine | 17.06 ± 1.54 | 24.03 ± 3.00 | 2.08 ± 0.15 | 1.05 ± 0.08 |
| CYP2C9 | Tolbutamide | 12.36 ± 1.14 | 12.65 ± 2.57 | 1.50 ± 0.19 | 0.78 ± 0.09 |
| CYP2C19 | (S)-Mephenytoin | 19.68 ± 2.70 | 25.46 ± 5.12 | 6.75 ± 0.96 | 3.60 ± 0.79 |
| CYP2D6 | Dextromethorphan | >100 | >100 | 11.73 ± 1.20 | 17.23 ± 1.68 |
| CYP3A4 | Midazolam | >100 | >100 | 15.47 ± 2.19 | 16.05 ± 1.91 |
| Testosterone | 55.64 ± 18.49 | >100 | 70.22 ± 21.80 | 6.78 ± 1.27 | |
| CYP2E1 | Chloroxazone | >100 | >100 | >100 | >25 |