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1.
Pharmaceutics ; 15(6)2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37376132

ABSTRACT

Drug solubility limits intravenous dosing for poorly water-soluble medicines, which misrepresents their bioavailability estimation. The current study explored a method using a stable isotope tracer to assess the bioavailability of drugs that are poorly water-soluble. HGR4113 and its deuterated analog, HGR4113-d7, were tested as model drugs. To determine the level of HGR4113 and HGR4113-d7 in rat plasma, a bioanalytical method using LC-MS/MS was developed. The HGR4113-d7 was intravenously administered to rats that were orally pre-administered HGR4113 at different doses; subsequently, the plasma samples were collected. HGR4113 and HGR4113-d7 were simultaneously determined in the plasma samples, and bioavailability was calculated using plasma drug concentration values. The bioavailability of HGR4113 was 53.3% ± 19.5%, 56.9% ± 14.0%, and 67.8% ± 16.7% after oral dosages of 40, 80, and 160 mg/kg, respectively. By eliminating the differences in clearance between intravenous and oral dosages at different levels, acquired data showed that the current method reduced measurement errors in bioavailability when compared to the conventional approach. The present study suggests a prominent method for evaluating the bioavailability of drugs with poor aqueous solubility in preclinical studies.

2.
Molecules ; 27(13)2022 Jul 05.
Article in English | MEDLINE | ID: mdl-35807562

ABSTRACT

Plants are an important source of drug development and numerous plant derived molecules have been used in clinical practice for the ailment of various diseases. The Toll-like receptor-4 (TLR-4) signaling pathway plays a crucial role in inflammation including rheumatoid arthritis. The TLR-4 binds with pro-inflammatory ligands such as lipopolysaccharide (LPS) to induce the downstream signaling mechanism such as nuclear factor κappa B (NF-κB) and mitogen activated protein kinases (MAPKs). This signaling activation leads to the onset of various diseases including inflammation. In the present study, 22 natural compounds were studied against TLR-4/AP-1 signaling, which is implicated in the inflammatory process using a computational approach. These compounds belong to various classes such as methylxanthine, sesquiterpene lactone, alkaloid, flavone glycosides, lignan, phenolic acid, etc. The compounds exhibited different binding affinities with the TLR-4, JNK, NF-κB, and AP-1 protein due to the formation of multiple hydrophilic and hydrophobic interactions. With TLR-4, rutin had the highest binding energy (-10.4 kcal/mol), poncirin had the highest binding energy (-9.4 kcal/mol) with NF-κB and JNK (-9.5 kcal/mol), respectively, and icariin had the highest binding affinity (-9.1 kcal/mol) with the AP-1 protein. The root means square deviation (RMSD), root mean square fraction (RMSF), and radius of gyration (RoG) for 150 ns were calculated using molecular dynamic simulation (MD simulation) based on rutin's greatest binding energy with TLR-4. The RMSD, RMSF, and RoG were all within acceptable limits in the MD simulation, and the complex remained stable for 150 ns. Furthermore, these compounds were assessed for the potential toxic effect on various organs such as the liver, heart, genotoxicity, and oral maximum toxic dose. Moreover, the blood-brain barrier permeability and intestinal absorption were also predicted using SwissADME software (Lausanne, Switzerland). These compounds exhibited promising physico-chemical as well as drug-likeness properties. Consequently, these selected compounds portray promising anti-inflammatory and drug-likeness properties.


Subject(s)
Toll-Like Receptor 4 , Transcription Factor AP-1 , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Humans , Inflammation/drug therapy , Molecular Docking Simulation , Molecular Dynamics Simulation , NF-kappa B/metabolism , Rutin/pharmacology , Signal Transduction , Transcription Factor AP-1/metabolism
3.
Biomed Pharmacother ; 142: 112015, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34388532

ABSTRACT

COVID-19, an infectious disease, has emerged as one of the leading causes of death worldwide, making it one of the severe public health issues in recent decades. nCoV, the novel SARS coronavirus that causes COVID-19, has brought together scientists in the quest for possible therapeutic and preventive measures. The development of new drugs to manage COVID-19 effectively is a challenging and time-consuming process, thus encouraging extensive investigation of drug repurposing and repositioning candidates. Several medications, including remdesivir, hydroxychloroquine, chloroquine, lopinavir, favipiravir, ribavirin, ritonavir, interferons, azithromycin, capivasertib and bevacizumab, are currently under clinical trials for COVID-19. In addition, several medicinal plants with considerable antiviral activities are potential therapeutic candidates for COVID-19. Statistical data show that the pandemic is yet to slow down, and authorities are placing their hopes on vaccines. Within a short period, four types of vaccines, namely, whole virus, viral vector, protein subunit, and nucleic acid (RNA/DNA), which can confer protection against COVID-19 in different ways, were already in a clinical trial. SARS-CoV-2 variants spread is associated with antibody escape from the virus Spike epitopes, which has grave concerns for viral re-infection and even compromises the effectiveness of the vaccines. Despite these efforts, COVID-19 treatment is still solely based on clinical management through supportive care. We aim to highlight the recent trends in COVID-19, relevant statistics, and clinical findings, as well as potential therapeutics, including in-line treatment methods, preventive measures, and vaccines to combat the prevalence of COVID-19.


Subject(s)
Antiviral Agents , COVID-19 Drug Treatment , COVID-19 Vaccines , SARS-CoV-2/drug effects , Antiviral Agents/classification , Antiviral Agents/pharmacology , COVID-19/classification , COVID-19/complications , COVID-19/prevention & control , COVID-19 Vaccines/classification , COVID-19 Vaccines/pharmacology , Drug Development/methods , Drug Discovery/methods , Drug Repositioning/methods , Humans
4.
Molecules ; 25(23)2020 Dec 02.
Article in English | MEDLINE | ID: mdl-33276545

ABSTRACT

According to WHO report, globally about 10 million active tuberculosis cases, resulting in about 1.6 million deaths, further aggravated by drug-resistant tuberculosis and/or comorbidities with HIV and diabetes are present. Incomplete therapeutic regimen, meager dosing, and the capability of the latent and/or active state tubercular bacilli to abide and do survive against contemporary first-line and second line antitubercular drugs escalate the prevalence of drug-resistant tuberculosis. As a better understanding of tuberculosis, microanatomy has discovered an extended range of new promising antitubercular targets and diagnostic biomarkers. However, there are still no new approved antitubercular drugs of routine therapy for several decades, except for bedaquiline, delamanid, and pretomanid approved tentatively. Despite this, innovative methods are also urgently needed to find potential new antitubercular drug candidates, which potentially decimate both latent state and active state mycobacterium tuberculosis. To explore and identify the most potential antitubercular drug candidate among various reported compounds, we focused to highlight the promising lead derivatives of isoniazid, coumarin, griselimycin, and the antimicrobial peptides. The aim of the present review is to fascinate significant lead compounds in the development of potential clinical drug candidates that might be more precise and effective against drug-resistant tuberculosis, the world research looking for a long time.


Subject(s)
Antitubercular Agents/pharmacology , Drug Design , Mycobacterium tuberculosis/drug effects , Pharmaceutical Preparations/administration & dosage , Pharmaceutical Preparations/chemistry , Tuberculosis, Multidrug-Resistant/drug therapy , Animals , Coumarins/chemistry , Humans , Isoniazid/chemistry , Peptides, Cyclic/chemistry , Pore Forming Cytotoxic Proteins/chemistry , Tuberculosis, Multidrug-Resistant/microbiology
5.
Nutrients ; 11(8)2019 Aug 19.
Article in English | MEDLINE | ID: mdl-31430927

ABSTRACT

Caffeine is commonly taken via the daily dietary consumption of caffeine-containing foods. The absorbed caffeine is metabolized to yield various metabolites by drug-metabolizing enzymes, and measuring the levels of each caffeine metabolite can provide useful information for evaluating the phenotypes of those enzymes. In this study, the urinary concentrations of caffeine and its 13 metabolites were determined, and the phenotypes of drug metabolic enzymes were investigated based on the caffeine metabolite ratios. Human urine samples were pretreated using solid phase extraction, and caffeine and its metabolites were analyzed using liquid chromatography-tandem mass spectrometry. Based on the urinary caffeine metabolite concentrations, the caffeine metabolite ratios were calculated for six human subjects at specified time points after caffeine intake. Variations in urinary metabolite levels among individuals and time points were reported. In addition, the resultant enzyme activities showed different patterns, depending on the metabolite ratio equations applied. However, some data presented a constant metabolite ratio range, irrespective of time points, even at pre-dose. This suggests the possibility of urinary caffeine metabolite analysis for routine clinical examination. These findings show that urinary caffeine and the metabolite analysis would be useful in evaluating metabolic phenotypes for personalized medicine.


Subject(s)
Arylamine N-Acetyltransferase/metabolism , Caffeine/metabolism , Caffeine/urine , Cytochrome P-450 CYP1A2/metabolism , Cytochrome P-450 CYP2A6/metabolism , Xanthine Oxidase/metabolism , Adult , Biomarkers/metabolism , Biomarkers/urine , Chromatography, High Pressure Liquid , Humans , Male , Middle Aged , Phenotype , Urinalysis , Young Adult
6.
Pharmaceutics ; 11(4)2019 Apr 03.
Article in English | MEDLINE | ID: mdl-30987254

ABSTRACT

Acetyl triethyl citrate (ATEC) is a water-soluble plasticizer used in pharmaceutical plasticized polymers. In this study, the pharmacokinetics and metabolism of ATEC were investigated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in rats. Plasma protein precipitation with methanol was used for sample preparation. For chromatographic separation, a C18 column was used. The mobile phases consisted of 0.1% formic acid and 90% acetonitrile, and gradient elution was used. The following precursor-product ion pairs were selected for reaction monitoring analysis: 319.1 m/z → 157 m/z for ATEC and 361.2 m/z → 185.1 m/z for tributyl citrate (internal standard) in positive ion mode. The LC-MS/MS method was fully validated and successfully applied to a pharmacokinetic study of ATEC in rats. The pharmacokinetic study showed that the volume of distribution and mean residence time of ATEC were higher after oral administration than after intravenous administration, pointing to extensive first-pass metabolism and distribution in tissue. In addition, the plasma concentration profile of the postulated metabolites of ATEC was investigated in plasma, urine, and feces. The resulting data indicated that ATEC was extensively metabolized and excreted mainly as metabolites rather than as the parent form. The developed analytical method and the data on the pharmacokinetics and metabolism of ATEC may be useful for understanding the safety and toxicity of ATEC.

7.
Environ Sci Pollut Res Int ; 25(5): 5033-5039, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29273993

ABSTRACT

Epoxidized soybean oil (ESBO) has been used in polyvinyl chloride (PVC)/polyvinylidene chloride (PVDC) food packaging cling film as a plasticizer and stabilizer. The aim of this study was to investigate the migration of ESBO from PVC/PVDC cling film, based on gas chromatography mass spectrometry (GC-MS). The specific migration of ESBO was evaluated using various food simulants (water, 4% acetic acid, 50% ethanol and n-heptane) for PVC and PVDC wrap products. ESBO did not migrate into water and 4% acetic acid for all the tested samples. However, it was released into 50% ethanol and n-heptane in several PVC/PVDC wraps, with maximum migration levels of 38.4 ± 0.7 and 37.4 ± 0.8 µg/mL, respectively. These results demonstrate that ESBO is capable of being released from PVC/PVDC wrap into amphiphilic/oily food and its migration should be regularly monitored.


Subject(s)
Food Contamination/analysis , Food Packaging/standards , Plasticizers/analysis , Polyvinyl Chloride/analogs & derivatives , Polyvinyl Chloride/chemistry , Soybean Oil/analysis , Gas Chromatography-Mass Spectrometry , Models, Theoretical
8.
Molecules ; 22(7)2017 Jul 24.
Article in English | MEDLINE | ID: mdl-28737724

ABSTRACT

The extract of Hedera helix L. (Araliaceae), a well-known folk medicine, has been popularly used to treat respiratory problems, worldwide. It is very likely that this herbal extract is taken in combination with conventional drugs. The present study aimed to evaluate the effects of H. helix extract on cytochrome P450 (CYP) enzyme-mediated metabolism to predict the potential for herb-drug interactions. A cocktail probe assay was used to measure the inhibitory effect of CYP. H. helix extracts were incubated with pooled human liver microsomes or CYP isozymes with CYP-specific substrates, and the formation of specific metabolites was investigated to measure the inhibitory effects. H. helix showed significant inhibitory effects on CYP2C8, CYP2C19 and CYP2D6 in a concentration-dependent manner. In recombinant CYP2C8, CYP2C19 and CYP2D6 isozymes, the IC50 values of the extract were 0.08 ± 0.01, 0.58 ± 0.03 and 6.72 ± 0.22 mg/mL, respectively. Further investigation showed that H. helix extract has a positive time-dependent inhibition property on both CYP2C8 and CYP2C19 with IC50 shift value of 2.77 ± 0.12 and 6.31 ± 0.25, respectively. Based on this in vitro investigation, consumption of herbal medicines or dietary supplements containing H. helix extracts requires careful attention to avoid any CYP-based interactions.


Subject(s)
Cytochrome P-450 CYP2C19/metabolism , Cytochrome P-450 CYP2C8/metabolism , Hedera/chemistry , Herbal Medicine/methods , Plants, Medicinal/chemistry , Araliaceae/chemistry , Humans , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Plant Extracts/pharmacology
9.
J Pharm Biomed Anal ; 145: 52-58, 2017 Oct 25.
Article in English | MEDLINE | ID: mdl-28648788

ABSTRACT

In this study, a robust, selective and simplified method was developed and validated for the simultaneous quantitative analysis of 23 underivatized amino acids in human serum using mixed-mode chromatography with tandem mass spectrometry (LC-MS/MS). Serum samples were deproteinized with acetonitrile and subjected to LC-MS/MS analysis. The chromatographic separation of amino acids was achieved using a mixed-mode column (150×3mm, 3µm) with a gradient elution system; the mobile phase consisted of 50mM ammonium formate and 0.1% formic acid in acetonitrile. The total run time was 22min. Eluted compounds were detected in the electrospray ionization-positive mode with multiple reaction monitoring. The validation study evaluated linearity, repeatability, intra and inter-day accuracy and precision, and matrix effect. The validation results were satisfactory in all the tested parameters. This method was successfully applied to the analysis of amino acids in the clinical sample of human serum.


Subject(s)
Amino Acids/blood , Chromatography, Liquid , Humans , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry
10.
Pharmacogn Mag ; 13(50): 236-239, 2017.
Article in English | MEDLINE | ID: mdl-28539714

ABSTRACT

BACKGROUND: Hovenia dulcis (Rhamnaceae) fruits are popularly used as herbal medicines or dietary supplements in Asian countries due to functions such as liver protection and detoxification from alcohol poisoning. Accordingly, it is very likely for dietary supplemental products, including H. dulcis fruit extracts, to be taken with prescription drugs. OBJECTIVE: In this study, possible food-drug interactions involving H. dulcis fruit extracts were evaluated based on the inhibition of cytochrome P450 (CYP) enzyme activity. MATERIAL AND METHODS: The water extract of H. dulcis fruit extracts was incubated in human liver microsomes with CYP-specific substrates. The formation of the CYP-specific metabolites was measured using liquid chromatography-tandem mass spectrometry. RESULTS: H. dulcis fruit extracts showed negligible effects on seven CYP isozyme activities at all concentrations tested. CONCLUSION: This result suggests that H. dulcis fruit extracts may have minimal pharmacokinetic interactions with coadministered drugs through the modulation of CYP enzymes. SUMMARY: Food-drug interactions involving H. dulcis fruit extracts were evaluated.The inhibition of CYPs by H. dulcis extracts was tested.H. dulcis extracts showed negligible effects on CYP activities.H. dulcis extracts may have minimal pharmacokinetic interactions with co-administered drugs. Abbreviations Used: CYP: cytochrome P450 enzymes, HPLC: High performance liquid chromatography, LC-MS/MS : liquid chromatography-tandem mass spectrometry, MRM: multiple-reaction monitoring.

11.
Bioorg Med Chem Lett ; 27(8): 1826-1830, 2017 04 15.
Article in English | MEDLINE | ID: mdl-28274629

ABSTRACT

Paradols are unsaturated ketones produced by biotransformation of shogaols in gingers. Among them, 6-paradol has been investigated as a new drug candidate due to its anti-inflammatory, apoptotic, and neuroprotective activities. In this study, the inhibitory effects of 6-paradol on the activities of cytochrome P450 (CYP) enzymes were investigated with human liver microsomes and recombinant CYP isozymes. 6-Paradol showed concentration-dependent inhibitory effects on CYP1A2, CYP2B6, CYP2C8, CYP2C9, and CYP2C19 isozymes, with IC50 values ranging from 3.8 to 21.4µM in recombinant CYP isozymes. However, the inhibition was not potentiated following pre-incubation, indicating that 6-paradol is not a mechanism-based inhibitor. These results suggest that pharmacokinetic drug-drug interactions might occur with 6-paradol, which must be considered in the process of new drug development.


Subject(s)
Cytochrome P-450 Enzyme Inhibitors/pharmacology , Cytochrome P-450 Enzyme System/metabolism , Guaiacol/analogs & derivatives , Ketones/pharmacology , Microsomes, Liver/drug effects , Pharmaceutical Preparations/metabolism , Zingiber officinale/chemistry , Cytochrome P-450 Enzyme Inhibitors/chemistry , Guaiacol/chemistry , Guaiacol/pharmacology , Humans , Ketones/chemistry , Microsomes, Liver/enzymology , Microsomes, Liver/metabolism , Recombinant Proteins/metabolism
12.
Planta Med ; 83(11): 895-900, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28288493

ABSTRACT

This study assessed the inhibitory effects of Garcinia cambogia extract on the cytochrome P450 enzymes in vitro. G. cambogia extract was incubated with cytochrome P450 isozyme-specific substrates in human liver microsomes and recombinant CYP2B6 isozyme, and the formation of the marker metabolites was measured to investigate the inhibitory potential on cytochrome P450 enzyme activities. The results showed that G. cambogia extract has significant inhibitory effects on CYP2B6 activity in a concentration-dependent manner. Furthermore, the inhibition was potentiated following preincubation with NADPH, indicating that G. cambogia extract is a time-dependent inhibitor of CYP2B6. Meanwhile, hydroxycitric acid, the major bioactive ingredient of G. cambogia extract, did not exhibit significant inhibition effects on cytochrome P450 enzyme activities. G. cambogia extract could modulate the pharmacokinetics of CYP2B6 substrate drugs and lead to interactions with those drugs. Therefore, caution may be required with respect to concomitant intake of dietary supplements containing G. cambogia extract with CYP2B6 substrates.


Subject(s)
Cytochrome P-450 CYP2B6 Inhibitors/isolation & purification , Garcinia cambogia/chemistry , Microsomes, Liver/drug effects , Plant Extracts/pharmacology , Cytochrome P-450 CYP2B6/metabolism , Cytochrome P-450 CYP2B6 Inhibitors/pharmacology , Humans , In Vitro Techniques , Microsomes, Liver/enzymology , Plants, Medicinal/chemistry
13.
J Pharm Biomed Anal ; 138: 92-99, 2017 May 10.
Article in English | MEDLINE | ID: mdl-28189891

ABSTRACT

In this study, various neurosteroids in brain and plasma were simultaneously determined using liquid chromatography-tandem mass spectrometry and their profile changes in a stress-induced rats were investigated. The investigated neurosteroids are as follows: progesterone (P4), 5α-dihydroprogesterone (5α-DHP), 5ß-dihydroprogesterone, estrone, androstenedione (AE), cortisol, cortisone, corticosterone (CORT), dehydroepiandrosterone (DHEA), pregnanolone (3α,5ß-THP), allopregnanolone (ALLO), 11-deoxycorticosterone (DOC), 11-deoxycortisol, pregnenolone (PREG), and 5α/5ß-tetrahydrodeoxycorticosterone (5α/5ß-THDOC). Brain and plasma samples were processed using solid-phase extraction with methanol and acetic acid (99:1), and derivatized with a hydroxylamine reagent. Separation was achieved within 13min at a flow rate of 0.4mL/min with a C18 column (3.0×50mm, 2.7µm). The triple quadrupole mass spectrometer was operated in the positive electrospray ionization mode. Using this method, the neurosteroid level variation was quantitated and investigated in the brain and plasma upon immobilization stress in rats. As a result, AE, CORT, DOC, P4, 5α-DHP, 5α/5ß-THDOC, DHEA, 3α,5ß-THP, ALLO, and PREG levels were significantly altered in both the brain and plasma samples when stress was induced. These findings demonstrated that stress leads to the alteration of the GABAergic neurosteroid profile. The present results will be helpful for furthering an understanding of the role of neurosteroids in stressed conditions.


Subject(s)
Brain/metabolism , Neurotransmitter Agents/blood , Neurotransmitter Agents/metabolism , Plasma/chemistry , Plasma/metabolism , Acetic Acid/chemistry , Animals , Chromatography, Liquid/methods , Male , Mass Spectrometry/methods , Methanol/chemistry , Neurotransmitter Agents/chemistry , Rats , Rats, Sprague-Dawley , Solid Phase Extraction/methods
14.
Biomed Chromatogr ; 31(4)2017 Apr.
Article in English | MEDLINE | ID: mdl-27572280

ABSTRACT

In this study, a rapid, sensitive, and reliable hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS) method for the determination of eurycomanone in rat plasma was developed and validated. Plasma samples were pretreated with a protein precipitation method and quercitrin was used as an internal standard (IS). A HILIC silica column (2.1 × 100 mm, 3 µm) was used for hydrophilic-based chromatographic separation, using the mobile phase of 0.1% formic acid with acetonitrile in gradient elution at a flow rate of 0.25 mL/min. Precursor-product ion pairs for multiple-reaction monitoring were m/z 409.1 → 391.0 for eurycomanone and m/z 449.1 → 303.0 for IS. The linear range was 2-120 ng/mL. The intra- and inter-day accuracies were between 95.5 and 103.4% with a precision of <4.2%. The developed method was successfully applied to the pharmacokinetic analysis of eurycomanone in rat plasma after oral dosing with pure compound and E. longifolia extract. The Cmax and AUC0-t , respectively, were 40.43 ± 16.08 ng/mL and 161.09 ± 37.63 ng h/mL for 10 mg/kg eurycomanone, and 9.90 ± 3.97 ng/mL and 37.15 ± 6.80 ng h/mL for E. longifolia extract (2 mg/kg as eurycomanone). The pharmacokinetic results were comparable with each other, based on the dose as eurycomanone.


Subject(s)
Chromatography, Liquid/methods , Plant Extracts/blood , Plant Extracts/pharmacokinetics , Quassins/blood , Quassins/pharmacokinetics , Tandem Mass Spectrometry/methods , Animals , Area Under Curve , Calibration , Eurycoma/chemistry , Hydrophobic and Hydrophilic Interactions , Limit of Detection , Male , Plant Extracts/administration & dosage , Rats, Sprague-Dawley , Reproducibility of Results
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1033-1034: 296-300, 2016 Oct 15.
Article in English | MEDLINE | ID: mdl-27595649

ABSTRACT

5-(2-Aminopropyl)-2,3-dihydrobenzofuran (5-APDB) is a designer drug of phenethylamine and amphetamine class. In this study, the in vitro metabolism of 5-APDB was investigated in rat and human liver microsomes and human hepatocytes to characterize its metabolites. 5-APDB was incubated with microsomes or hepatocytes, and the reaction mixture was analyzed using liquid chromatography-quadrupole time-of-flight with tandem mass spectrometry (LC-Q/TOF-MS). 5-APDB was metabolized to yield three metabolites (M1, M2 and M3). These metabolites were structurally characterized on the basis of accurate mass analysis and MS/MS fragmentation patterns. Metabolite M1 and M2 were identified as hydroxylated metabolites in the benzofuran moiety; M3 was a reduced metabolite which may be generated from M1 or M2 via dehydration. These results provide evidence for the in vivo 5-APDB metabolism, and would be forensically useful for the detection of 5-APDB and its metabolites in biological samples.


Subject(s)
Benzofurans/metabolism , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Animals , Hepatocytes/metabolism , Humans , Metabolic Networks and Pathways , Microsomes, Liver/metabolism , Rats
16.
J Pharm Biomed Anal ; 131: 160-166, 2016 Nov 30.
Article in English | MEDLINE | ID: mdl-27592254

ABSTRACT

Methylenedioxypyrovalerone (MDPV) has emerged in recent years as a recreational substance with psychostimulant properties. In this study, in vitro metabolites of MDPV were characterized based on liquid chromatography/quadrupole-time-of-flight mass spectrometry (LC/QTOF MS). MDPV was incubated with human liver microsomes, human recombinant cDNA-expressed cytochrome P450 enzymes and flavin monooxygenase (FMO). MDPV was metabolized to yield eight metabolites (M1-M8) with major metabolic reactions such as demethylenation and oxidation. Among them, M6 was assigned as an N-oxide metabolite. FMO was found to be a principal enzyme responsible for the formation of M6; FMO1 and FMO3 were the main enzymes involved in N-oxidation of MDPV.


Subject(s)
Benzodioxoles/pharmacokinetics , Microsomes, Liver/metabolism , Oxygenases/metabolism , Pyrrolidines/pharmacokinetics , Cytochrome P-450 Enzyme System/metabolism , Humans , In Vitro Techniques , Molecular Structure , Synthetic Cathinone
17.
J Pharm Biomed Anal ; 129: 90-95, 2016 Sep 10.
Article in English | MEDLINE | ID: mdl-27411171

ABSTRACT

Hederacoside C is a principal bioactive pharmaceutical ingredient of Hedera helix leaf extracts. H. helix extracts have long been used in folk medicine for the treatment of respiratory disorders. Currently, hederacoside C is investigated as a promising candidate for the treatment of respiratory diseases. In this study, an accurate, sensitive, rapid, and reliable bioanalytical method was developed for the determination of hederacoside C in rat plasma using ultra high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). For sample preparation, plasma proteins were precipitated with 0.1% acetic acid in acetonitrile. Waters UPLC BEH C18 (2.1mm I.D.×100mm, 1.7µm) column was used for chromatographic separation. A gradient elution of mobile phases consisting of 0.02% acetic acid in distilled water (solvent A) and 0.02% acetic acid in acetonitrile (solvent B) was used at a flow rate of 0.3mL/min. The multiple reaction monitoring (MRM) mode was used for mass spectrometric detection; the MRM transitions were m/z 1219.7→m/z 469.2 for hederacoside C and m/z 1108.3→m/z 221.2 for ginsenoside Rb1 (internal standard) in the negative ionization mode. A calibration curve was constructed in the range of 10-1000ng/mL. The intra- and inter-day precision and accuracy were within 5%. The developed UPLC-MS/MS method was successfully applied in a pharmacokinetic study of hederacoside C in rats. Hederacoside C was quickly but inadequately absorbed from the gastrointestinal tract of rats resulting in extremely low bioavailability and relatively slow clearance.


Subject(s)
Hedera , Oleanolic Acid/analogs & derivatives , Plant Extracts/blood , Respiration Disorders/blood , Tandem Mass Spectrometry/methods , Animals , Chromatography, High Pressure Liquid/methods , Male , Oleanolic Acid/administration & dosage , Oleanolic Acid/blood , Oleanolic Acid/isolation & purification , Plant Extracts/administration & dosage , Plant Extracts/isolation & purification , Rats , Rats, Sprague-Dawley , Respiration Disorders/drug therapy
18.
Molecules ; 21(6)2016 Jun 18.
Article in English | MEDLINE | ID: mdl-27322236

ABSTRACT

Kinsenoside, the herb-derived medicine isolated from the plant Anoect chilus, has diverse pharmacological actions, and it is considered to be a promising antihyperlipidemic drug candidate. This study evaluates the effects of kinsenoside on CYP enzyme-mediated drug metabolism in order to predict the potential for kinsenoside-drug interactions. Kinsenoside was tested at different concentrations of 0.1, 0.3, 1, 3, 10, 30, and 100 µM in human liver microsomes. The c Cktail probe assay based on liquid chromatography-tandem mass spectrometry was conducted to measure the CYP inhibitory effect of kinsenoside. Subsequently, the metabolism profiles of amlodipine and lovastatin in human liver microsomes were analyzed following co-incubation with kinsenoside. The concentration levels of the parent drug and the major metabolites were compared with the kinsenoside-cotreated samples. The effect of kinsenoside was negligible on the enzyme activity of all the CYP isozymes tested even though CYP2A6 was slightly inhibited at higher concentrations. The drug-drug interaction assay also showed that the concomitant use of kinsenoside has a non-significant effect on the concentration of lovastatin or amlodipine, and their major metabolites. So, it was concluded that there is almost no risk of drug interaction between kinsenoside and CYP drug substrates via CYP inhibition.


Subject(s)
4-Butyrolactone/analogs & derivatives , Cytochrome P-450 CYP2A6/metabolism , Hypolipidemic Agents/pharmacology , Inactivation, Metabolic/genetics , Monosaccharides/pharmacology , 4-Butyrolactone/chemistry , 4-Butyrolactone/pharmacology , Amlodipine/metabolism , Amlodipine/pharmacology , Chromatography, Liquid , Cytochrome P-450 Enzyme Inhibitors/chemistry , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Cytochrome P-450 Enzyme System/drug effects , Drug Interactions , Humans , Hypolipidemic Agents/chemistry , Inactivation, Metabolic/drug effects , Lovastatin/metabolism , Lovastatin/pharmacology , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Monosaccharides/chemistry , Substrate Specificity , Tandem Mass Spectrometry
19.
Environ Sci Pollut Res Int ; 23(10): 10270-5, 2016 May.
Article in English | MEDLINE | ID: mdl-27053047

ABSTRACT

Phthalate acid esters are widely used as plasticizers to impart plastic flexibility in various industrial applications. In this study, the content of seven phthalates, dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), di-(2-ethylhexyl) adipate (DEHA), di-2-ethylhexyl phthalate (DEHP), di-n-octyl phthalate (DNOP), di-isononyl phthalate (DINP), and di-isodecyl phthalate (DIDP) were determined in paper cups using gas chromatography-mass spectrometry (GC-MS). In addition, the potential migration of these seven phthalates from paper cups into various food stimulants under different conditions was evaluated. The levels of DBP, DEHA, DEHP, and DNOP were in the ranges of 0.07-3.14, 0.16-42.69, 0.45-58.56, and 0.3-2.4 mg/kg, respectively. Meanwhile, BBP, DINP, and DIDP were not detected in most of the tested samples. In the migration test, DEHA was released to 50 % ethanol and n-heptane in a time-dependent manner and the maximum migration levels were 65.62 ± 3.61 and 95.56 ± 19.76 µg/L, respectively. The release of other phthalates was very low or negligible. These results demonstrated that paper cups are not a significant source of phthalate exposure; however, DEHA could be released from paper cups into alcoholic beverages or oily liquid beverages in the human diet.


Subject(s)
Cooking and Eating Utensils , Paper , Phthalic Acids/analysis , Adipates , Beverages , Dibutyl Phthalate/analysis , Diethylhexyl Phthalate/analysis , Gas Chromatography-Mass Spectrometry/methods , Heptanes , Humans
20.
Molecules ; 21(3): 331, 2016 Mar 10.
Article in English | MEDLINE | ID: mdl-26978330

ABSTRACT

Eurycoma longifolia Jack (known as tongkat ali), a popular traditional herbal medicine, is a flowering plant of the family Simaroubaceae, native to Indonesia, Malaysia, Vietnam and also Cambodia, Myanmar, Laos and Thailand. E. longifolia, is one of the well-known folk medicines for aphrodisiac effects as well as intermittent fever (malaria) in Asia. Decoctions of E. longifolia leaves are used for washing itches, while its fruits are used in curing dysentery. Its bark is mostly used as a vermifuge, while the taproots are used to treat high blood pressure, and the root bark is used for the treatment of diarrhea and fever. Mostly, the roots extract of E. longifolia are used as folk medicine for sexual dysfunction, aging, malaria, cancer, diabetes, anxiety, aches, constipation, exercise recovery, fever, increased energy, increased strength, leukemia, osteoporosis, stress, syphilis and glandular swelling. The roots are also used as an aphrodisiac, antibiotic, appetite stimulant and health supplement. The plant is reported to be rich in various classes of bioactive compounds such as quassinoids, canthin-6-one alkaloids, ß-carboline alkaloids, triterpene tirucallane type, squalene derivatives and biphenyl neolignan, eurycolactone, laurycolactone, and eurycomalactone, and bioactive steroids. Among these phytoconstituents, quassinoids account for a major portion of the E. longifolia root phytochemicals. An acute toxicity study has found that the oral Lethal Dose 50 (LD50) of the alcoholic extract of E. longifolia in mice is between 1500-2000 mg/kg, while the oral LD50 of the aqueous extract form is more than 3000 mg/kg. Liver and renal function tests showed no adverse changes at normal daily dose and chronic use of E. longifolia. Based on established literature on health benefits of E. longifolia, it is important to focus attention on its more active constituents and the constituents' identification, determination, further development and most importantly, the standardization. Besides the available data, more evidence is required regarding its therapeutic efficacy and safety, so it can be considered a rich herbal source of new drug candidates. It is very important to conserve this valuable medicinal plant for the health benefit of future generations.


Subject(s)
Eurycoma/chemistry , Herbal Medicine , Medicine, Traditional , Plant Extracts/chemistry , Plant Extracts/pharmacology , Animals , Eurycoma/classification , Humans , Metabolomics/methods
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