Dependence of benzo[a]pyrene metabolic profile on the concentration of cumene hydroperoxide with uninduced and induced rat liver microsomes

AbstractProtoberberine alkaloids including berberine, palmatine, jatrorrhizine, coptisine, and epiberberine are major components in many medicinal plants. They have been widely used for the treatment of cancer, inflammation, diabetes, depression, hypertension, and various infectious areas. However, the metabolism of five protoberberine alkaloids among different species has not been clarified previously. In order to elaborate on the in vitro metabolism of them, a comparative analysis of their metabolic profile in rat, rhesus monkey, and human liver microsomes was carried out using ultrahigh-performance liquid chromatography coupled with a high-resolution linear trap quadrupole-Orbitrap mass spectrometer (UHPLC-electrospray ionization-Orbitrap MS) for the first time. Each metabolite was identified and semiquantified by its accurate mass data and peak area. Fifteen metabolites were characterized based on accurate MS/MS spectra and the proposed MS/MS fragmentation pathways including demethylation, hydroxylation, and methyl reduction. Among them, the content of berberine metabolites in human liver microsomes was similar with those in rhesus monkey liver microsomes, whereas berberine in rat liver microsomes showed no demethylation metabolites and the content of metabolites showed significant differences with that in human liver microsomes. On the contrary, the metabolism of palmatine in rat liver microsomes resembled that in human liver microsomes. The content of jatrorrhizine metabolites presented obvious differences in all species. The HR-ESI-MS/MS fragmentation behavior of protoberberine alkaloids and their metabolic profile in rat, rhesus monkey, and human liver microsomes were investigated for the first time. The results demonstrated that the biotransformation characteristics of protoberberine alkaloids among different species had similarities as well differences that would be beneficial for us to better understand the pharmacological activities of protoberberine alkaloids.

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DETECTION OF FREE RADICAL SPECIES DERIVED FROM CUMENE HYDROPEROXIDE IN MODEL HEMEPROTEIN SYSTEMS AND IN RAT LIVER MICROSOMES BY SPIN-TRAPPING TECHNIQUES

Microsomes, Drug Oxidations and Chemical Carcinogenesis ◽

10.1016/b978-0-12-187701-9.50060-7 ◽

1980 ◽

pp. 319-322

Author(s):

Brenda Walker Griffin

Keyword(s):

Free Radical ◽

Rat Liver ◽

Liver Microsomes ◽

Cumene Hydroperoxide ◽

Spin Trapping ◽

Rat Liver Microsomes ◽

Radical Species ◽

Free Radical Species

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Metabolic Analysis of Triptolide Microspheres in Human, Dog, Rabbit and Rat Liver Microsomes with UPLC-MS/MS Method

Current Pharmaceutical Analysis ◽

10.2174/1573412917999200909143213 ◽

2020 ◽

Vol 17 ◽

Author(s):

LiJuan Wang ◽

Yan Liu ◽

Rui Li ◽

DongXian He

Keyword(s):

Rat Liver ◽

Liver Microsomes ◽

Internal Standard ◽

Gradient Elution ◽

Rat Liver Microsomes ◽

Good Precision ◽

Kinetics Parameters ◽

Measure Concentration ◽

Standard Curve ◽

Variation Of Parameters

Objectives: Triptolide (TPL) has been shown to have a good clinical effect on rheumatoid arthritis (RA). We designed TPL microspheres (TPL-MS) and investigated its metabolic behavior in human, dog, rabbit and rat liver microsomes (HLM, DLM, RLM and SDRLM) with UPLC-MS/MS method. Methods: First, a UPLC-MS/MS method was established to measure concentration of TPL in samples. The sample was separated on a C18 column (2.1×100 mm, 1.8μm) and eluted with a gradient elution. The precursor ion/product ion were m/z 378.1/361.0 for TPL and 260.0/116.2 for the internal standard. Then T1/2, Vmax and CLint were calculated from the above data. Finally, the metabolites of TPL-MS were identified by high-resolution UPLC-MS/MS. The sample was separated on a C18 column (2.1×100 mm, 2.2 μm) and eluted with isocratic elution. Mass spectrometric detection was carried out on a thermo Q-exactive mass spectrometer with HESI. The scanning range of precursor ions was from m/z 50 to m/z 750. Result and Discussion: Through several indicators including standard curve, precision, accuracy, stability, matrix effect and recovery rate, the enzymatic kinetics parameters including T1/2, Vmax and CLint were completed. Several metabolites of TPL-MS were identified. Conclusion: UPLC-MS/MS method is an accurate and sensitive method for determination of TPL in liver microsome samples with good precision, accuracy and stability. The variation of parameters indicated that the microspheres can delay the elimination of TPL in liver microsomes. The metabolism of TPL-MS varied among species, but no new metabolites appeared.

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