Tertiary Oxidation of Deoxycholate Is Predictive of CYP3A Activity in Dogs
Autor: | Xuejing Li, Lanlan Gui, Lian Yang, Qingliang Wu, Ping-Ping Zhu, Wushuang Zeng, Changxiao Liu, Wei Jia, Xian-Wen Tan, Yiting Hu, Ke Lan |
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Rok vydání: | 2021 |
Předmět: |
Adult
Male medicine.drug_class CYP3A Midazolam Pharmaceutical Science Pharmacology 030226 pharmacology & pharmacy 03 medical and health sciences chemistry.chemical_compound Dogs 0302 clinical medicine Pharmacokinetics In vivo medicine Animals Cytochrome P-450 CYP3A Humans GABA Modulators Enterohepatic circulation Bile acid Chemistry Deoxycholic acid Metabolism Enzyme Activation Ketoconazole 030220 oncology & carcinogenesis Microsomes Liver Cytochrome P-450 CYP3A Inhibitors Female Oxidation-Reduction Deoxycholic Acid Forecasting medicine.drug |
Zdroj: | Drug Metabolism and Disposition. 49:369-378 |
ISSN: | 1521-009X 0090-9556 |
Popis: | Deoxycholic acid (DCA, 3α, 12α-dihydroxy-5β-cholan-24-oic acid) is the major circulating secondary bile acid, which is synthesized by gut flora in the lower gut and selectively oxidized by CYP3A into tertiary metabolites, including 1β,3α,12α-trihydroxy-5β-cholan-24-oic acid (DCA-1β-ol) and 3α,5β,12α-trihydroxy-5β-cholan-24-oic acid (DCA-5β-ol) in humans. Since DCA has the similar exogenous nature and disposition mechanisms as xenobiotics, this work aimed to investigate whether the tertiary oxidations of DCA are predictive of in vivo CYP3A activities in beagle dogs. In vitro metabolism of midazolam (MDZ) and DCA in recombinant canine CYP1A1, 1A2, 2B11, 2C21, 2C41, 2D15, 3A12, and 3A26 enzymes clarified that CYP3A12 was primarily responsible for either the oxidation elimination of MDZ or the regioselective oxidation metabolism of DCA into DCA-1β-ol and DCA-5β-ol in dog liver microsomes. Six male dogs completed the CYP3A intervention studies including phases of baseline, inhibition (ketoconazole treatments), recovery, and induction (rifampicin treatments). The oral MDZ clearance after a single dose was determined on the last day of the baseline, inhibition, and induction phases, and subjected to correlation analysis with the tertiary oxidation ratios of DCA detected in serum and urine samples. The results confirmed that the predosing serum ratios of DCA oxidation, DCA-5β-ol/DCA, and DCA-1β-ol/DCA were significantly and positively correlated both intraindividually and interindividually with oral MDZ clearance. It was therefore concluded that the tertiary oxidation of DCA is predictive of CYP3A activity in beagle dogs. Clinical transitional studies following the preclinical evidence are promising to provide novel biomarkers of the enterohepatic CYP3A activities. Significance Statement Drug development, clinical pharmacology, and therapeutics are under insistent demands of endogenous CYP3A biomarkers that avoid unnecessary drug exposure and invasive sampling. This work has provided the first proof-of-concept preclinical evidence that the CYP3A catalyzed tertiary oxidation of deoxycholate, the major circulating secondary bile acid synthesized in the lower gut by bacteria, may be developed as novel in vivo biomarkers of the enterohepatic CYP3A activities. |
Databáze: | OpenAIRE |
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