Protein expression levels of drug-metabolizing enzymes in human liver microsomal fraction
The expression of enzymes was determined in microsomal fraction of human liver tissues from 17 donors. Each value represents the mean ± S.D. (n = 17). When the quantification value was under the limit of quantification, the value was taken as 0 pmol/mg protein for calculating the mean value of each protein. Amounts of CYP3A4 were determined by using the equation shown under Experimental Procedures. UGT1A4 was under the limit of quantification in all samples.
| Enzyme | No. of Quantified Donors | Protein Amount | Max/Min | |||
|---|---|---|---|---|---|---|
| Mean | S.D. | Max | Min | |||
| pmol/mg protein | ||||||
| CYP2C9 | 17 | 76.3 | 26.6 | 115 | 40.2 | 2.9 |
| CYP2E1 | 17 | 66.1 | 27.4 | 147 | 36.3 | 4.0 |
| CYP3A4 | 17 | 60.4 | 75.0 | 270 | 6.22 | 43.4 |
| CYP2A6 | 17 | 56.2 | 45.0 | 168 | 5.45 | 30.8 |
| CYP2C8 | 17 | 30.0 | 22.6 | 83.5 | 5.66 | 14.8 |
| CYP1A2 | 17 | 25.1 | 21.2 | 65.5 | 3.26 | 20.1 |
| CYP4A11 | 17 | 21.8 | 8.7 | 46.5 | 9.29 | 5.0 |
| CYP2D6 | 17 | 17.2 | 8.4 | 36.4 | 6.16 | 5.9 |
| CYP2B6 | 17 | 6.72 | 3.19 | 14.9 | 4.05 | 3.7 |
| CYP2C19 | 17 | 5.31 | 5.20 | 22.2 | 2.08 | 10.7 |
| CYP3A43 | 14 | 4.10 | 2.01 | 6.42 | <LOQ | |
| CYP3A5 | 17 | 3.86 | 3.43 | 17.1 | 2.48 | 6.9 |
| CYP3A7 | 13 | 2.40 | 3.09 | 9.39 | <LOQ | |
| P450R | 17 | 71.6 | 17.0 | 99.0 | 41.7 | 2.4 |
| UGT1A6 | 17 | 114 | 54 | 277 | 45.0 | 6.2 |
| UGT2B7 | 17 | 84.3 | 29.5 | 146 | 53.1 | 2.8 |
| UGT2B15 | 17 | 61.8 | 21.5 | 103 | 24.2 | 4.3 |
| UGT1A1 | 17 | 33.2 | 11.5 | 59.7 | 20.8 | 2.9 |
| UGT1A9 | 17 | 25.9 | 6.3 | 38.0 | 15.5 | 2.5 |
| UGT1A3 | 17 | 17.3 | 7.8 | 37.1 | 8.16 | 4.5 |
| Na+/K+-ATPase | 17 | 12.1 | 2.3 | 15.8 | 7.42 | 2.1 |
Max, maximum; Min, minimum; <LOQ, under the lower limit of quantification.