In vitro hepatic conversion of the anticancer agent nemorubicin to its active metabolite PNU-159682 in mice, rats and dogs: A comparison with human liver microsomes

Metabolism of both carbamazepine (CBZ) and oxcarbaze-pine (OCBZ) were catalyzed by human liver microsomes and microsomes from livers of CBZ-induced or non-induced C57BL/6 mice. Human placental microsomes metabolized only OCBZ. Mouse liver microsomes metabolized CBZ to carbamazepine-10,11-epoxide (CBZ-E), 10- hydroxy-10,11-dihydro-carbamazepine (10-OH-CBZ), 3- hydroxy-carbamazepine (3-OH-CBZ), 10,11-trans-dihydroxy-10,11-dihydro-carbamazepine (10,11-D) and to an unidentified metabolite. CBZ-pretreatment of mice increased both ethoxyresorufin O-deethylase activity in the liver and the amount of CBZ-E in microsomal incubations regardless of the age of mice. Human liver microsomes catalyzed the formation of CBZ to 9-hydroxymethyl-10-carbamoyl acridan (9-AC) in addition to CBZ-E, 3-OH-CBZ and 10-OH-CBZ. OCBZ was metabolized to its active metabolite in all incubations. An unknown metabolite was also present in some of the incubations. Human liver microsomes catalyzed only minute covalent binding of CBZ and OCBZ to DNA. Binding of OCBZ was, however, one order of magnitude greater than binding of CBZ. Human placental micro-somes from the mothers on CBZ therapy did not catalyze CBZ metabolism. The same microsomes catalyzed OCBZ metabolism to 10-OH-CBZ and to an unknown metabolite. These results indicate autoinduction in CBZ metabolism in mouse liver. Due to the higher binding of OCBZ than CBZ to DNA in vitro, further studies on the potential mutagenicity of OCBZ may be warranted.

Download Full-text

Evaluation of Diallyl Sulfide Analogs for Cytotoxicity, Inhibition of CYP2E1, and Metabolite Profiling Using In Vitro Cell Culture, Human Liver Microsomes and LCMS/MS

10.26226/morressier.57d6b2b8d462b8028d88ee12 ◽

2016 ◽

Author(s):

Mohammad Rahman

Keyword(s):

Cell Culture ◽

Metabolite Profiling ◽

Human Liver ◽

Liver Microsomes ◽

Human Liver Microsomes ◽

Diallyl Sulfide ◽

In Vitro Cell Culture

Download Full-text

Nontargeted Metabolomics by High-Resolution Mass Spectrometry to Study the In Vitro Metabolism of a Dual Inverse Agonist of Estrogen-Related Receptors β and γ, DN203368

Pharmaceutics ◽

10.3390/pharmaceutics13060776 ◽

2021 ◽

Vol 13 (6) ◽

pp. 776

Author(s):

Sin-Eun Kim ◽

Seung-Bae Ji ◽

Euihyeon Kim ◽

Minseon Jeong ◽

Jina Kim ◽

...

Keyword(s):

Mass Spectrometry ◽

High Resolution ◽

Human Liver ◽

High Resolution Mass Spectrometry ◽

Liver Microsomes ◽

Human Liver Microsomes ◽

Rat Liver Microsomes ◽

High Resolution Mass ◽

Resolution Mass

DN203368 ((E)-3-[1-(4-[4-isopropylpiperazine-1-yl]phenyl) 3-methyl-2-phenylbut-1-en-1-yl] phenol) is a 4-hydroxy tamoxifen analog that is a dual inverse agonist of estrogen-related receptor β/γ (ERRβ/γ). ERRγ is an orphan nuclear receptor that plays an important role in development and homeostasis and holds potential as a novel therapeutic target in metabolic diseases such as diabetes mellitus, obesity, and cancer. ERRβ is also one of the orphan nuclear receptors critical for many biological processes, such as development. We investigated the in vitro metabolism of DN203368 by conventional and metabolomic approaches using high-resolution mass spectrometry. The compound (100 μM) was incubated with rat and human liver microsomes in the presence of NADPH. In the metabolomic approach, the m/z value and retention time information obtained from the sample and heat-inactivated control group were statistically evaluated using principal component analysis and orthogonal partial least-squares discriminant analysis. Significant features responsible for group separation were then identified using tandem mass spectra. Seven metabolites of DN203368 were identified in rat liver microsomes and the metabolic pathways include hydroxylation (M1-3), N-oxidation (M4), N-deisopropylation (M5), N,N-dealkylation (M6), and oxidation and dehydrogenation (M7). Only five metabolites (M2, M3, and M5-M7) were detected in human liver microsomes. In the conventional approach using extracted ion monitoring for values of mass increase or decrease by known metabolic reactions, only five metabolites (M1-M5) were found in rat liver microsomes, whereas three metabolites (M2, M3, and M5) were found in human liver microsomes. This study revealed that nontargeted metabolomics combined with high-resolution mass spectrometry and multivariate analysis could be a more efficient tool for drug metabolite identification than the conventional approach. These results might also be useful for understanding the pharmacokinetics and metabolism of DN203368 in animals and humans.

Download Full-text