TABLE 1

Enzyme activities of main DMEs

Mice were treated with silybin (50 mg/kg or 150 mg/kg, once daily) for a consecutive 2 weeks. Twenty-four hours after the last administration, the mice were sacrificed and their livers were immediately removed to prepared microsomes. Enzyme activities of main P450s and UGTs were tested using the typical probe substrate approach. Data are shown as mean ± S.D. (n = 3).

SubstratesActivity of DMEs (pmol/min/mg microsome protein)
VehicleSilybin (50 mg/kg)Silybin (150 mg/kg)
Phenacetin516.23 ± 79.93440.59 ± 33.02319.10 ± 27.71a
Diclofenac159.06 ± 4.39168.32 ± 8.92126.97 ± 1.51a
Chlorzoxazone1446.31 ± 29.981553.31 ± 59.821332.36 ± 81.52
Midazolam1291.11 ± 98.691305.59 ± 29.69907.76 ± 60.01b
β-estradiol718.71 ± 42.12621.71 ± 16.36a419.42 ± 21.95b
4-MU75,459.46 ± 9478.70109,474.65 ± 2324.0283,348.31 ± 8070.37
Naloxone286.74 ± 38.05295.84 ± 31.74289.04 ± 29.78
  • a P < 0.01 represents the comparison of activities of DMEs between Silybin treated groups and vehicle group.

  • b P < 0.001.