Interspecies metabolic diversity of harmaline and harmine in in vitro 11 mammalian liver microsomes

Abstract

The β-carboline alkaloids harmaline and harmine are widely present in hallucinogenic plants with great potential for treating depression, Parkinson's disease, and Alzheimer's disease. The present study was to elucidate metabolic difference of harmaline and harmine in 11 mammalian liver microsomes in order to quantitate species-specific metabolic profiles. Using the probe substrate reaction, the enzymatic activities for 8 CYP450 isozymes of 11 liver microsomes were characterized. Combining ultra performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q/TOF-MS) and ultra performance liquid chromatography combined with electrospray ionization quadrupole tandem mass spectrometry (UPLC-ESI-MS/MS) methods, 18 metabolites for harmaline and 11 for harmine were identified. The metabolism patterns differences of them presented discrepancy in the quality and quantity of metabolites. It was notable that O-sulfate conjugation was detected in all species except sheep. The intrinsic clearance CL values for the metabolites harmine and harmol in rabbits (37.5 and 42.4 μL/min/mg) were higher than those in other animals, while dogs (16.2 and 16.7 μL/min/mg) and humans (16.0 and 16.3 μL/min/mg) exhibited similar in vitro metabolic clearance. These observations suggested that harmaline and harmine were rapidly metabolized in liver microsomes of rat, mouse, and rabbit; moderately metabolized in human and dog; while weakly metabolized in sheep. Comprehensive analysis of the metabolism indicated that dogs and humans showed considerable similarity in the elimination of parent drugs, metabolic profiles, and catalytic processes. To summarize, these findings illustrated that in vitro studies of harmaline and harmine metabolic profiles in different species are helpful for the proper selection and interpretation of animal models for pharmacological and toxicological evaluation, and will ultimately provide useful guidance for the development of β-carboline alkaloids. Copyright © 2016 John Wiley & Sons Ltd.

Exposure Characteristics of the Analogous β-Carboline Alkaloids Harmaline and Harmine Based on the Efflux Transporter of Multidrug Resistance Protein 2

“…Harmaline and harmine concentrations were simultaneous quantitative determined on a Waters-ACQUITY™ UPLC system (Waters Corp., Milford, MA, USA) using an ACQUITY UPLC BEH C 18 column (50 × 2.1 mm, 1.7 μm particle size). Mass spectrometric detection was performed using a triple quadrupole mass spectrometer (Waters Corp., Milford, MA, USA) equipped with electrospray ionization in positive ionization mode, and all other instrumental parameters were set according to our previous study (Li et al, 2016 ). The UPLC-ESI-MS/MS method was well-validated (data not shown) and the analytical method was successfully applied to determine the concentration of harmine and harmaline in the HBSS buffers.…”

“…Harmaline or harmine (2 μM) was incubated with human liver microsomes (0.5 mg protein/mL) for 0, 5, 10, 20, 30, 45, 60, 90 min using our previous method (Li et al, 2016 ). The residual percentage of harmaline or harmine was plotted vus incubation time.…”

“…Morton, are ubiquitously available in a variety of medicinal plants (Khan et al, 2013 ; Ingale and Kasture, 2014 ; Stanković et al, 2015 ; Li et al, 2017 ). Harmaline and harmine are endogenously produced in human and animal tissues as a low molecular weight product of secondary metabolism (Li et al, 2016 ). They could affect the content of neurotransmitters by strong inhibition of monoamine oxidase (Jiang et al, 2015 ), acetylcholinesterase (Liu et al, 2014 ), and myeloperoxidase (Bensalem et al, 2014 ).…”

“…It revealed that the efflux ratios ( ER ) of harmaline and harmine were <1.0, suggesting a passive diffusion mechanism for their transport across the Caco-2 monolayer. However, composite evidences indicate that these alkaloids possess a strong cytotoxicity to various cell lines, particularly harmine (Li et al, 2016 ). The drug concentration (250–500 μM) may exceed the safe dosage in the Caco-2 cells, which will result in damage to cells and then change the activity of transporters or the permeability of the cell monolayers.…”

Interspecies Variation of In Vitro Stability and Metabolic Diversity of YZG-331, a Promising Sedative-Hypnotic Compound

“…Values of p < 0.05 were considered to statistically significant. The contents of metabolites from LMs incubation were evaluated by principal component analysis (PCA) using SPSS software ( Li et al, 2016 ; Ma et al, 2016 ).…”