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Vincent A van der Mark, D Rudi de Waart, Valery Shevchenko, Ronald P J Oude Elferink, Robert A F M Chamuleau, Ruurdtje Hoekstra
Dimethyl sulfoxide (DMSO) induces cellular differentiation and expression of drug metabolic enzymes in the human liver cell line HepaRG. However, DMSO also induces cell death and interferes with cellular activities. The aim of this study was to examine if overexpression of the constitutive androstane receptor (CAR, NR1I3), the nuclear receptor controlling various drug metabolism genes, would sufficiently promote differentiation and drug metabolism in HepaRG cells, optionally without using DMSO. By stable lentiviral overexpression of CAR, HepaRG cultures were less affected by DMSO in total protein content and obtained increased resistance to acetaminophen- and amiodarone-induced cell death...
October 25, 2016: Drug Metabolism and Disposition: the Biological Fate of Chemicals
Alena Vanduchova, Veronika Tomankova, Pavel Anzenbacher, Eva Anzenbacherova
The influence of metabolites of sulforaphane, natural compounds present in broccoli (Brassica oleracea var. botrytis italica) and in other cruciferous vegetables, on drug-metabolizing cytochrome P450 (CYP) enzymes in human liver microsomes and possible entry of sulforaphane into human hepatic cells were investigated. Metabolites studied are compounds derived from sulforaphane by the mercapturic acid pathway (conjugation with glutathione and by following reactions), namely sulforaphane glutathione and sulforaphane cysteine conjugates and sulforaphane-N-acetylcysteine...
October 25, 2016: Journal of Medicinal Food
Teresa T Vo, Sheeba Varghese Gupta
For treatment-naïve patients with human immunodeficiency virus infection, efavirenz (EFV) together with tenofovir and emtricitabine were once widely prescribed given its efficacy and ease of administration in a combination pill. However, the high rate of central nervous system toxicities from EFV prompted the United States Department of Health and Human Services to move the EFV-based regimen from the recommended to the alternative category. For patients who do meet the criteria for newer recommended antiretroviral treatments, EFV is a viable option and is often the mainstay of treatment outside the United States, as newer antiretroviral treatments are more expensive...
October 25, 2016: Pharmacotherapy
Barry C Jones, Helen Rollison, Susanne A Johansson, Kajsa P Kanebratt, Craig Lambert, Karthick Vishwanathan, Tommy B Andersson
Induction of cytochrome P450 (CYP) can impact the efficacy and safety of a drug molecule upon multiple dosing of co-administered drugs. This strategy is focused on CYP3A since the majority of clinically relevant cases of CYP induction are related to this enzyme. However, the in vitro evaluation of induction is applicable to other CYP enzymes but the in vivo relevance cannot be assessed because the scarcity of relevant clinical data. In the pre-clinical phase, compounds are screened using PXR reporter gene assay and, if necessary, structure-activity relationships (SAR) are developed...
October 24, 2016: Drug Metabolism and Disposition: the Biological Fate of Chemicals
A D B Vliegenthart, R A Kimmitt, J H Seymour, N Z Homer, J I Clarke, M Eddleston, A Gray, D M Wood, P I Dargan, J G Cooper, D J Antoine, D J Webb, S C Lewis, D N Bateman, J W Dear
: Acetaminophen (paracetamol-APAP) is the commonest cause of drug-induced liver injury in the Western world. Reactive metabolite production by cytochrome P450 enzymes (CYP-metabolites) causes hepatotoxicity. We explored the toxicokinetics of human circulating APAP metabolites following overdose. Plasma from patients treated with acetylcysteine (NAC) for a single APAP overdose was analysed from discovery (N=116) and validation (N=150) patient cohorts. In the discovery cohort, patients who developed acute liver injury (ALI) had higher CYP-metabolites than those without ALI...
October 22, 2016: Clinical Pharmacology and Therapeutics
Maïlys De Sousa Mendes, Gabrielle Lui, Yi Zheng, Claire Pressiat, Deborah Hirt, Elodie Valade, Naïm Bouazza, Frantz Foissac, Stephane Blanche, Jean-Marc Treluyer, Saik Urien, Sihem Benaboud
BACKGROUND: Pregnant women and their fetuses are exposed to numerous drugs; however, they are orphan populations with respect to the safety and efficacy of drugs. Therefore, the prediction of maternal and fetal drug exposure prior to administration would be highly useful. METHODS: A physiologically-based pharmacokinetic (PBPK) model for nevirapine, which is metabolized by the cytochrome P450 (CYP) 3A4, 2B6 and 2D6 pathways, was developed to predict maternal and fetal pharmacokinetics (PK)...
October 21, 2016: Clinical Pharmacokinetics
Laureen A Lammers, Roos Achterbergh, Marcel C M Pistorius, Yuma Bijleveld, Emmely M de Vries, Anita Boelen, Heinz-Josef Klümpen, Johannes A Romijn, RonA A Mathôt
BACKGROUND: The metabolic activity of P450 enzymes in vivo can be determined by using selective probe drugs. The simultaneous administration of multiple CYP-specific probe drugs is commonly referred to as the "cocktail approach." Disadvantages of a cocktail are large volumes of samples required for analysis and time-consuming analyses. The aim of this study was to develop and validate a simplified but sensitive method for the simultaneous quantification of five probe drugs (caffeine (CYP1A2), metoprolol (CYP2D6), midazolam (CYP3A4), omeprazole (CYP2C19), and S-warfarin (CYP2C9)) in a previously validated cocktail using an LC-MS/MS method...
October 19, 2016: Therapeutic Drug Monitoring
Bera Rammohan, Karmakar Samit, Das Chinmoy, Saha Arup, Kundu Amit, Sarkar Ratul, Karmakar Sanmoy, Adhikari Dipan, Sen Tuhinadri
BACKGROUND: Traditionally GS is used to treat diabetes mellitus. Drug-herb interaction of GS via cytochrome P450 enzyme system by substrate cocktail method using HLM has not been reported. OBJECTIVE: To evaluate the in-vitro modulatory effects of GS extracts (aqueous, methanol, ethyl acetate, chloroform and n-hexane) and deacylgymnemic acid (DGA) on human CYP1A2, 2C8, 2C9, 2D6 and 3A4 activities in HLM. MATERIAL AND METHODS: Probe substrate-based LCMS/MS method was established for all CYPs...
July 2016: Pharmacognosy Magazine
Nikolaos Tsamandouras, Tomasz Kostrzewski, Cynthia L Stokes, Linda G Griffith, David J Hughes, Murat Cirit
In this work, we first describe the population variability in hepatic drug metabolism using cryopreserved hepatocytes from 5 different donors cultured in a perfused 3D human liver microphysiological system and then show how the resulting data can be integrated with a modeling and simulation framework to accomplish in vitro-in vivo translation. For each donor, metabolic depletion profiles of 6 compounds (phenacetin, diclofenac, lidocaine, ibuprofen, propranolol and prednisolone) were measured, along with metabolite formation, mRNA levels of 90 metabolism-related genes, and markers of functional viability (LDH release, albumin and urea production)...
October 19, 2016: Journal of Pharmacology and Experimental Therapeutics
Tania E Perez Jimenez, Katrina L Mealey, Tamara L Grubb, Stephen A Greene, Michael H Court
Tramadol is widely used to manage mild to moderately painful conditions in dogs. However, this use is controversial since clinical efficacy studies in dogs showed conflicting results, while pharmacokinetic studies demonstrated relatively low circulating concentrations of O-desmethyltramadol (M1). Analgesia has been attributed to the opioid effects of M1, while tramadol and the other major metabolite (N-desmethyltramadol, M2) are considered inactive at opioid receptors. The aims of this study were to determine whether cytochrome P450 (CYP) dependent M1 formation by dog liver microsomes is slower compared with cat and human liver microsomes; and identify the CYPs responsible for M1 and M2 formation in canine liver...
October 6, 2016: Drug Metabolism and Disposition: the Biological Fate of Chemicals
Julian A Michely, Sascha K Manier, Achim T Caspar, Simon D Brandt, Jason Wallach, Hans H Maurer
3-Methoxyphencyclidine (3-MeO-PCP) and 3-methoxyrolicyclidine (3-MeO-PCPy) are two new psychoactive substances (NPS). The aims of the present study were the elucidation of their metabolic fate in rat and pooled human liver microsomes (pHLM), the identification of the cytochrome P450 (CYP) isoenzymes involved, and the detectability using standard urine screening approaches (SUSA) after intake of common users' doses using gas chromatography-mass spectrometry (GC-MS), liquid chromatography-multi-stage mass spectrometry (LC-MSn), and liquid chromatography-high-resolution tandem mass spectrometry (LC-HR-MS/MS)...
October 18, 2016: Current Neuropharmacology
Tsuyoshi Chiba, Keiko Noji, Shohei Shinozaki, Sachina Suzuki, Keizo Umegaki, Kentaro Shimokado
OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is associated with impaired liver function, and resveratrol could suppress NAFLD progression. This study examined the effects of NAFLD on the expression of major cytochrome P450 (CYP) subtypes in the liver and whether the expression could be attenuated by resveratrol. METHODS: C57BL/6 mice (male, 10 weeks of age) were fed a high-fat and high-sucrose (HFHS) diet to induce NAFLD. Major Cyp subtype mRNA expression in the liver was measured by real-time RT-PCR...
October 19, 2016: Journal of Pharmacy and Pharmacology
Devendra Kumar, Neerja Trivedi, Rakesh K Dixit
AIMS/BACKGROUND: This study was to investigated the synergistic effect of polyherbal formulations (PHF) of Allium sativum L., Eugenia jambolana Lam., Momordica charantia L., Ocimum sanctum Linn., and Psidium guajava L. in the inhibition/induction of hepatic and intestinal cytochrome P450 (CYPs) and Phase-II conjugated drug metabolizing enzymes (DMEs). Consumption of these herbal remedy has been extensively documented for diabetes treatment in Ayurveda. METHODOLOGY: PHF of these five herbs was prepared, and different doses were orally administered to Sprague-Dawley rats of different groups except control group...
September 2016: Journal of Intercultural Ethnopharmacology
Ramona Jühlen, Dana Landgraf, Angela Huebner, Katrin Koehler
It has been shown that the nucleoporin ALADIN plays a significant role in the redox homeostasis of the cell but its function in steroidogenesis contributing to adrenal atrophy in triple A syndrome remains largely unknown. In an attempt to identify new interaction partners of ALADIN, co-immunoprecipitation followed by proteome analysis was conducted in different expression models using the human adrenocortical tumour cell line NCI-H295R. Our results suggest an interaction of ALADIN with the microsomal protein PGRMC2...
October 17, 2016: Biology Open
Jonathan David Tyzack, Peter A Hunt, Matthew D Segall
We describe methods for predicting Cytochrome P450 (CYP) metabolism incorporating both pathway-specific reactivity and isoform-specific accessibility considerations. Semi-empirical quantum mechanical (QM) simulations, parameterized using experimental data and ab initio calculations, estimate the reactivity of each potential site of metabolism in the context of the whole molecule. Ligand-based models, trained using high quality regioselectivity data, correct for orientation and steric effects of the different CYP isoform binding pockets...
October 18, 2016: Journal of Chemical Information and Modeling
Meghan MacKenzie, Richard Hall
PURPOSE: Knowledge of how alterations in pharmacogenomics and pharmacogenetics may affect drug therapy in the intensive care unit (ICU) has received little study. We review the clinically relevant application of pharmacogenetics and pharmacogenomics to drugs and conditions encountered in the ICU. SOURCE: We selected relevant literature to illustrate the important concepts contained within. PRINCIPAL FINDINGS: Two main approaches have been used to identify genetic abnormalities - the candidate gene approach and the genome-wide approach...
October 17, 2016: Canadian Journal of Anaesthesia, Journal Canadien D'anesthésie
Wenwen Wang, Yanqin Yang, Zhewen Xiong, Jiamin Kong, Xinlu Fu, Feihai Shen, Zhiying Huang
Triptolide (TP), a diterpene triepoxide, is a major active component of Tripterygium wilfordii extracts, which are prepared as tablets and has been used clinically for the treatment of inflammation and autoimmune disorders. However, TP's therapeutic potential is limited by severe adverse effects. In a previous study, we reported that TP induced mitochondria dependent apoptosis in cardiomyocytes. Glycogen synthase kinase-3β (GSK-3β) is a multifunctional serine/threonine kinase that plays important roles in the necrosis and apoptosis of cardiomyocytes...
October 14, 2016: Toxicology and Applied Pharmacology
Ping-Ping Lin, Xue-Ning Li, Fei Yuan, Wei-Li Chen, Meng-Jie Yang, Hong-Rong Xu
Huperzine A (HupA), one of the reversible and selective acetylcholinesterase inhibitors derived from Chinese herb Huperzia Serrata, possesses affirmative action of ameliorating cognitive dysfunction of Alzheimer's disease. Up to now, the effects of HupA on human cytochrome P450s (CYPs) have not been fully elucidated. The purpose of the present study was to clarify the metabolic pathway of HupA in vitro and in vivo, and to evaluate the CYPs inhibition/induction profile of HupA in vitro. The catalytic activity of CYP enzymes (CYP1A2, 2A6, 2C9, 2C19, 2D6, 2E1 and 3A4) was measured by the quantification of specific enzyme substrates using validated liquid chromatography-tandem mass spectrometry (LC/MS/MS) methods...
October 14, 2016: Biochemical and Biophysical Research Communications
Sedar Karakurt
Expression of a drug and xenobiotic metabolizing enzymes, cytochrome P450s (CYPs), and antioxidant enzymes can be modulated by various factors. The flavonoid rutin was investigated for its anti-carcinogen and protective effects as well as modulatory action on CYPs and phase II enzymes in human hepatocellular carcinoma cells. Rutin inhibited proliferation of HEPG2 cells in a dose-dependent manner with the IC50 value of 52.7 μmol L-1 and invasion of HEPG2 cells (21.6 %, p = 0.0018) and colony formation of those invaded cells (57...
December 1, 2016: Acta Pharmaceutica
María A Latorre, María L Romito, Alejandro Larriera, Gisela L Poletta, Pablo A Siroski
Agricultural activities associated mainly with soybean crops affect the natural environment and wildlife by habitat destruction and the extensive use of agrochemicals. The aim of this study was to evaluate immunotoxic effects of the insecticides cypermethrin (CYP) and endosulfan (END) in Caiman latirostris analyzing total blood cell count (TWBC) and differential white blood cell count (DWBC) after in ovo and in vivo exposure. Eggs (in ovo) and hatchlings (in vivo) from nests harvested in natural habitats were artificially incubated and reared under controlled conditions in the Proyecto Yacaré (Gob...
October 17, 2016: Journal of Immunotoxicology
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