Figure 12.

The effect of UAs concentration on P4503A4 and UGT activity. The modulation of: (A,B) testosterone β-hydroxylation with P4503A4 by C-2045 and C-2053 (C) glucuronidation activity of human recombinant UGT isoenzymes studied with the specific substrates: SN-38 for UGT1A1, epirubicin for UGT2B7 and TFK for UGT2B15 by C-2028. Values are expressed as the mean ± SD of duplicate experiments. Enzymatic activities towards standard substrates in the absence of UAs were normalized to 100%. Comparisons were made using one-way ANOVA, followed by Bonferroni’s multiple comparisons test, or an unpaired t-test. Levels were considered significant at * p < 0.05; ** p < 0.01; *** p < 0.001.