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Biomedical Chromatography : BMC Jan 2022Coumarins are a group of natural compounds commonly found in the families of Rutaceae and Umbelliferae. 7-Isopentenyloxycoumarin (ISC), auraptene (AUR), and...
Coumarins are a group of natural compounds commonly found in the families of Rutaceae and Umbelliferae. 7-Isopentenyloxycoumarin (ISC), auraptene (AUR), and umbelliprenin (UM) belong to prenyloxycoumarins (PYCs), which link isopentenyl, geranyl, and farnesyl group at C7 position, respectively. The substituent of 7-ethoxycoumarin (ETC) is the ethyl group. In this study, UPLC-ESI-QTOF-MS (ultra-performance liquid chromatography-electrospray ionization-quadrupole time of flight-MS)-based metabolomics was used to evaluate the in vivo and in vitro metabolism of PYCs. Results showed that ETC produced 10 known metabolites, and ISC was transformed into 17 metabolites in vivo and in vitro, which were undescribed compounds. A total of 35 AUR metabolites, including 34 undescribed metabolites were identified, and 21 metabolites were reported for the first time in UM. The results indicated that hydroxylation and N-acetylcysteine conjugation were the common metabolic reactions for PYCs. The metabolic rates of ETC, ISC, AUR and UM were 26%, 36%, 81%, and 38%, respectively, in human liver microsome, while they were 24%, 40%, 80%, and 37%, respectively, in mouse liver microsomes. In addition, recombinant cytochrome P450s (CYPs) screening showed that CYP1A1, 2C19, 3A4, and 3A5 were the major metabolic enzymes involved in the formation of hydroxylation metabolites. Together, these results suggest that the isopentenyl group plays an important role in the metabolism of PYCs.
Topics: Animals; Chromatography, High Pressure Liquid; Coumarins; Humans; Male; Metabolomics; Mice; Mice, Inbred C57BL; Microsomes, Liver; Pentanols; Tandem Mass Spectrometry
PubMed: 34494281
DOI: 10.1002/bmc.5239 -
Life Science Alliance Feb 2023The ability to investigate tissues and organs through an integrated systems biology approach has been thought to be unobtainable in the field of structural biology,...
The ability to investigate tissues and organs through an integrated systems biology approach has been thought to be unobtainable in the field of structural biology, where the techniques mainly focus on a particular biomacromolecule of interest. Here we report the use of cryo-electron microscopy (cryo-EM) to define the composition of a raw human kidney microsomal lysate. We simultaneously identify and solve cryo-EM structures of four distinct kidney enzymes whose functions have been linked to protein biosynthesis and quality control, biosynthesis of retinoic acid, gluconeogenesis and glycolysis, and the regulation and metabolism of amino acids. Interestingly, all four of these enzymes are directly linked to cellular processes that, when disrupted, can contribute to the onset and progression of diabetes. This work underscores the potential of cryo-EM to facilitate tissue and organ proteomics at the atomic level.
Topics: Humans; Cryoelectron Microscopy; Microsomes; Kidney; Amino Acids; Glycolysis
PubMed: 36450445
DOI: 10.26508/lsa.202201580 -
International Journal of Molecular... Aug 2022Phytochemicals like pyrrolizidine alkaloids (PAs) can affect the health of humans and animals. PAs can occur for example in tea, honey or herbs. Some PAs are known to be...
Phytochemicals like pyrrolizidine alkaloids (PAs) can affect the health of humans and animals. PAs can occur for example in tea, honey or herbs. Some PAs are known to be cytotoxic, genotoxic, and carcinogenic. Upon intake of high amounts, hepatotoxic and pneumotoxic effects were observed in humans. This study aims to elucidate different toxicokinetic parameters like the uptake of PAs and their metabolism with in vitro models. We examined the transport rates of differently structured PAs (monoester, open-chained diester, cyclic diester) over a model of the intestinal barrier. After passing the intestinal barrier, PAs reach the liver, where they are metabolized into partially instable electrophilic metabolites interacting with nucleophilic centers. We investigated this process by the usage of human liver, intestinal, and lung microsomal preparations for incubation with different PAs. These results are completed with the detection of apoptosis as indicator for bioactivation of the PAs. Our results show a structure-dependent passage of PAs over the intestinal barrier. PAs are structure-dependently metabolized by liver microsomes and, to a smaller extent, by lung microsomes. The detection of apoptosis of A549 cells treated with lasiocarpine and monocrotaline following bioactivation by human liver or lung microsomes underlines this result. Conclusively, our results help to shape the picture of PA toxicokinetics which could further improve the knowledge of molecular processes leading to observed effects of PAs in vivo.
Topics: Animals; Carcinogens; Humans; Liver; Microsomes, Liver; Pyrrolizidine Alkaloids; Toxicokinetics
PubMed: 36012484
DOI: 10.3390/ijms23169214 -
Xenobiotica; the Fate of Foreign... May 2022S-011-1559 is a tyrosine-derived novel benzoxazine CDRI molecule targeted to the oestrogen-related receptor (ER-α/β) modulator in breast cancer. To explore the...
S-011-1559 is a tyrosine-derived novel benzoxazine CDRI molecule targeted to the oestrogen-related receptor (ER-α/β) modulator in breast cancer. To explore the pharmacokinetics of S-011-1559, a selective and sensitive bioanalytical method using LC-MS/MS was established and validated in different biological matrices of female rats.Blood-to-plasma ratio and plasma protein binding (PPB) of S-011-1559 were found to be <1 and >97% in both rats and humans, respectively. The human serum albumin (HSA) and alpha-1-acid glycoprotein (AAG) binding was found in the range of > 68 to 45% and >14% respectively. Half-life and intrinsic clearance by microsomal stability study were found to be 28.83 min and 0.05 mL/min/mg in rats, 78.35 min and 0.036 mL/min/mg in humans, respectively. The IC value of S-011-1559 against CYP isoforms was revealed to moderately inhibit CYP2D6 by a reversible non-competitive mechanism.Tissue distribution of S-011-1559 on single intravenous injection at 2 mg/kg was found in the order of C lungs > C mammary gland > C spleen > C heart > C kidney > C liver > C brain.The data from the present study provides crucial information about S-011-1559 for further development as a novel potential drug candidate in modulating ER-α/β receptors of lung and breast neoplasia.
Topics: Animals; Breast Neoplasms; Chromatography, Liquid; Female; Humans; Microsomes, Liver; Rats; Tandem Mass Spectrometry; Tissue Distribution
PubMed: 35819259
DOI: 10.1080/00498254.2022.2101033 -
Chemical Research in Toxicology Jun 2022As a selective β-receptor antagonist, metoprolol tartrate (MTA) is commonly used to treat cardiovascular diseases such as hypertension and angina pectoris. There have...
As a selective β-receptor antagonist, metoprolol tartrate (MTA) is commonly used to treat cardiovascular diseases such as hypertension and angina pectoris. There have been cases of liver injury induced by MTA, but the mechanism of hepatotoxicity induced by MTA is not clear. The purposes of this study were to identify the reactive metabolites of MTA, to determine the pathway for the metabolic activation of MTA, and to define a possible correlation between the metabolic activation and cytotoxicity of MTA. Three oxidative metabolites (M1-M3), a glutathione (GSH) conjugate (M4), and an -acetyl cysteine (NAC) conjugate (M5) were detected in rat liver microsomal incubations containing MTA and GSH or NAC. M4 was also detected in cultured rat primary hepatocytes and bile of rats given MTA, and M5 was detected in the urine of MTA-treated rats. A quinone methide intermediate may be produced from the metabolic activation process and . The metabolite was reactive to glutathione and -acetyl cysteine. MTA induced marked cytotoxicity in cultured rat primary hepatocytes. Pretreatment of aminobenzotriazole, a nonselective P450 enzyme inhibitor, attenuated the susceptibility of hepatocytes to MTA cytotoxicity.
Topics: Animals; Rats; Acetylcysteine; Glutathione; Metoprolol; Microsomes, Liver
PubMed: 35575346
DOI: 10.1021/acs.chemrestox.2c00052 -
Bioorganic Chemistry Sep 2021The upregulation of the CB receptors in neuroinflammation and cancer and their potential visualization with PET (positron emission tomography) could provide a valuable...
The upregulation of the CB receptors in neuroinflammation and cancer and their potential visualization with PET (positron emission tomography) could provide a valuable diagnostic and therapy-monitoring tool in such disorders. However, the availability of reliable CB-selective imaging probes is still lacking in clinical practice. We have recently identified a benzothiazole-2-ylidine amide hit (6a) as a highly potent CB ligand. With the aim of enhancing its CB over CB selectivity and introducing structural sites suitable for radiolabeling, we herein describe the development of fluorinated and methoxylated benzothiazole derivatives endowed with extremely high CB binding affinity and an exclusive selectivity to the CB receptor. Compounds 14, 15, 18, 19, 21, 24 and 25 displayed subnanomolar CBK values (ranging from 0.16 nM to 0.68 nM) and interestingly, all of the synthesized compounds completely lacked affinity at the CB receptor (K > 10,000 nM for all compounds), indicating their remarkably high CB over CB selectivity factors. The fluorinated analogs, 15 and 21, were evaluated for their in vitro metabolic stability in mouse and human liver microsomes (MLM and HLM). Both 15 and 21 displayed an exceptionally high stability (98% and 91% intact compounds, respectively) after 60 min incubation with MLM. Contrastingly, a 5- and 2.8-fold lower stability was demonstrated for compounds 15 and 21, respectively, upon incubation with HLM for 60 min. Taken together, our data present extremely potent and selective CB ligands as credible leads that can be further exploited for F- or C-radiolabeling and utilization as PET tracers.
Topics: Animals; Benzothiazoles; Dose-Response Relationship, Drug; Drug Development; Halogenation; Humans; Ligands; Mice; Microsomes, Liver; Molecular Structure; Receptor, Cannabinoid, CB2; Structure-Activity Relationship
PubMed: 34375194
DOI: 10.1016/j.bioorg.2021.105191 -
Chemical Research in Toxicology Dec 2021Capsaicin, primarily known as the pungent ingredient in hot peppers, is rapidly metabolized in the human body by enzymatic processes altering the pharmacological as well...
Capsaicin, primarily known as the pungent ingredient in hot peppers, is rapidly metabolized in the human body by enzymatic processes altering the pharmacological as well as toxicological properties. Herein, the oxidative transformation of capsaicin was investigated with electrochemistry as well as human liver microsomal incubations. The reaction mixtures were analyzed with liquid chromatography-mass spectrometry. Structure elucidation involved accurate mass measurements and multistage tandem mass spectrometry experiments. In total, 126 transformation products were detected. Electrochemistry provided evidence for 101 transformation products and the microsomal incubations for 46 species. 21 compounds were observed with both approaches. Identified oxidative pathways likely occurring during the phase I metabolism included dehydrogenation, O-demethylation, and hydroxylation reactions as well as combinations thereof. Furthermore, trapping of reactive intermediates either with glutathione or with electrochemically activated ribonucleosides provided evidence for the possible production of phase II metabolites and covalent adducts with a genetic material. Evidence for the occurrence of some capsaicin metabolites in humans was obtained by urine screening.
Topics: Capsaicin; Chromatography, Liquid; Electrochemical Techniques; Healthy Volunteers; Humans; Mass Spectrometry; Microsomes, Liver; Oxidation-Reduction
PubMed: 34879203
DOI: 10.1021/acs.chemrestox.1c00288 -
Cannabis and Cannabinoid Research Dec 2023The year 2020 began with the world being flounced with a wave of novel coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) disease, named...
The year 2020 began with the world being flounced with a wave of novel coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) disease, named COVID-19. Based on promising pre-clinical and clinical data, remdesivir (RDV) was the first drug to receive FDA approval and so far, it is the most common therapy for treatment of SARS-CoV-2/MERS-CoV. However, following intravenous administration, RDV metabolizes majorly by human liver carboxylesterase 1 (CES1) and marginally by the CYP3A4 enzyme in merely less than an hour. Its resultant active metabolite is a hydrophilic nucleoside with very limited accumulation within lung tissues. Therefore, there is a need to investigate strategies to overcome such premature metabolism issues and improve the antiviral efficacy of RDV at the target site. Considering the major CES1-mediated metabolism of RDV on systemic administration, we intend to explore the remarkable CES1 plus CYP3A4 inhibitory activity of cannabidiol (CBD) against microsomal metabolism of RDV to indicate its therapeutic potential as an adjuvant to RDV in the treatment and management of COVID-19. We investigated the human liver microsomal metabolism of RDV in the presence of two potential CES1 inhibitors-CBD and nelfinavir, and two standard CYP3A4 inhibitors-ritonavir (RITO) and cyclosporin A. The microsomal metabolism assay was further validated by using a well-characterized CYP3A4-selective substrate, midazolam (MDZ), in the presence of CBD and RITO. Our findings depicted that RDV was rapidly and completely metabolized by human liver microsomes within 60 min. Coincubation with CBD substantially reduced microsomal metabolism of RDV and prolonged its half-life from 8.93 to 31.07 min. CBD showed significantly higher inhibition of RDV compared with known CES1 and CYP3A4 inhibitors. Inhibition of MDZ metabolism by CBD and RITO further validated the assay. The current study strongly suggests that CBD significantly inhibits human liver microsomal metabolism of RDV and extends its half-life. Thus, concomitant administration of CBD with RDV intravenous injection could be a promising strategy to prevent premature metabolism in COVID-19 patients.
Topics: Humans; Cannabidiol; Microsomes, Liver; Cytochrome P-450 CYP3A; Cytochrome P-450 CYP3A Inhibitors; SARS-CoV-2; COVID-19; Midazolam; Liver
PubMed: 34918945
DOI: 10.1089/can.2021.0109 -
Journal of Pharmaceutical and... Sep 2021Irisflorentin is one of the bioactive constituents from the root of Belamcanda chinensis (L.) DC, which displayed anti-inflammatory and anti-tumor activities. In this... (Review)
Review
Irisflorentin is one of the bioactive constituents from the root of Belamcanda chinensis (L.) DC, which displayed anti-inflammatory and anti-tumor activities. In this work, the in vitro metabolism of irisflorentin was investigated using liver microsomes and hepatocytes. The metabolites were identified by ultra-high performance liquid chromatography combined with quadrupole/orbitrap tandem mass spectrometry. Under the current conditions, a total of 11 metabolites were detected and structurally identified according to accurate masses, fragment ions and retention times. Metabolite M10, identified as 6,7-dihydroxy-5,3',4',5'-tetramethoxy isoflavone, was biosynthesized and unambiguously characterized by nuclear magnetic resonance spectroscopy. The metabolic pathways of irisflorentin included oxidation, demethylation and glucuronidation. M10 was the most abundant metabolite in all tested species. Further phenotyping studies revealed that α-naphthoflavone and ketoconazole displayed significant inhibitory effect on the formation of M10. Cytochrome P450 (CYP) 1A2 and 3A4 were the major enzymes responsible for the formation of M10 by using individual recombinant human CYP450 enzymes. For the first time the current study provides an overview of the in vitro metabolic fates of irisflorentin, which is helpful for us to predict the human metabolism and the potential drug-drug interactions caused by irisflorentin.
Topics: Chromatography, High Pressure Liquid; Humans; Isoflavones; Microsomes, Liver; Tandem Mass Spectrometry
PubMed: 34214765
DOI: 10.1016/j.jpba.2021.114222 -
Journal of Biochemical and Molecular... Jun 2021Tuberculosis, an airborne infectious disease, results in a high morbidity and mortality rate. The continuous emergence of TB resistance strains including MDR...
Tuberculosis, an airborne infectious disease, results in a high morbidity and mortality rate. The continuous emergence of TB resistance strains including MDR (multidrug-resistant tuberculosis), XDR (extensive drug-resistant tuberculosis), and especially TDR (totally drug-resistant tuberculosis) is a major public health threat and has intensified the need to develop new antitubercular agents. A natural product, curcumin, possesses diverse biological activities but suffers due to a lack of water solubility and bioavailability. To overcome these limitations, a series of 17 water-soluble monocarbonyl curcuminoids was synthesized and evaluated for antimycobacterial activity. All compounds exhibited good to moderate anti-TB activity with MIC in the range of 3.12-25.0 µM, out of which 7c and 7p were found the most potent compounds with MIC in the range of 3.12-6.25 µM. Furthermore, these compounds were observed to be nonhaemolytic, nontoxic, and stable under both physiological as well as reducing conditions. In-vitro metabolic stability data of the representative compound 7p with the human liver microsome revealed that these compounds possess a moderate metabolism with a half-life of 1.2 h and an intrinsic clearance of 1.12 ml/h/mg.
Topics: Antitubercular Agents; Diarylheptanoids; Humans; Microbial Sensitivity Tests; Microsomes, Liver; Mycobacterium tuberculosis
PubMed: 33751730
DOI: 10.1002/jbt.22754