A5083171669- Pharmacogenetics and Drug Metabolism
- Drug Transport and Resistance Mechanisms
- Computational Drug Discovery Methods
- Eicosanoids and Hypertension Pharmacology
- Analytical Chemistry and Chromatography
- Pharmacological Effects and Toxicity Studies
- 3D Printing in Biomedical Research
- Estrogen and related hormone effects
- Synthesis and Biological Evaluation
- Drug-Induced Hepatotoxicity and Protection
- Genomics, phytochemicals, and oxidative stress
- Inflammatory mediators and NSAID effects
- Receptor Mechanisms and Signaling
- Metabolomics and Mass Spectrometry Studies
- Glutathione Transferases and Polymorphisms
- Innovative Microfluidic and Catalytic Techniques Innovation
- Diet and metabolism studies
- Animal testing and alternatives
- Mycotoxins in Agriculture and Food
- Cancer Cells and Metastasis
- Bioactive Compounds and Antitumor Agents
- Statistical Methods in Clinical Trials
- Antibiotics Pharmacokinetics and Efficacy
- Neuroscience and Neuropharmacology Research
- Protein Interaction Studies and Fluorescence Analysis
AbbVie (United States)
2018-2024
IQ Samhällsbyggnad
2023
AbbVie (Japan)
2021
Corning (United States)
2013-2018
BD Biosciences (United States)
2002-2016
Weatherford College
2013
Becton Dickinson (United States)
2013
University of Massachusetts Chan Medical School
1998-2001
Foundation for Biomedical Research
1996-1998
Oregon State University
1994-1995
Inhibition of cytochrome P450 catalytic activity is a principal mechanism for pharmacokinetic drug-drug interactions. Rapid, in vitro testing inhibition potential part the current paradigm identifying drug candidates likely to give such We have explored extent that qualitative and quantitative parameters are dependent on (CYP) 3A4 probe substrate. (e.g., IC(50) values from 8-point curves) or activation most compounds varied dramatically depending fluorometric substrates CYP3A4...
Complex in vitro models (CIVM) offer the potential to improve pharmaceutical clinical drug attrition due safety and/ or efficacy concerns. For this technology have an impact, establishment of robust characterization and qualification plans constructed around specific contexts use (COU) is required. This article covers output from a workshop between Food Drug Administration (FDA) Innovation Quality Microphysiological Systems (IQ MPS) Affiliate. The intent was understand how CIVM technologies...
We have tested a panel of 29 cDNA-expressed rat and human enzymes with 9 fluorometric substrates to determine the P450 isoform selectivity in catalysis fluorescent products. The examined were dibenzyl fluorescein, 7-benzyloxyquinoline (BQ), 3-cyano-7-ethoxycoumarin, 3-cyano-7-methoxycoumarin, 7-methoxy-4-trifluoromethylcoumarin, 3-[2-(N,N-diethyl-N-methylamino)ethyl]-7-methoxy-4-methylcoumarin (AMMC), 3-[2-(N,N-diethyl-N-methylamino)ethyl]-7-methoxy-4-trifluoromethylcoumarin,...
Azamulin [14-O-(5-(2-amino-1,3,4-triazolyl)thioacetyl)-dihydromutilin] is an azole derivative of the pleuromutilin class antiinfectives. We tested inhibition potency azamulin toward 18 cytochromes P450 using human liver microsomes or from insect cells expressing single isoforms. In a competitive model, IC(50) values for CYP3A (0.03-0.24 microM) were at least 100-fold lower than all other non-CYP3A enzymes except CYP2J2 ( approximately 50-fold lower). The value with heterologously expressed...
To study cytochrome P-450 (CYP) 2B6 contribution to methoxychlor metabolism within human liver microsomes and initiate an investigation of CYP2B6 protein expression, we developed a polyclonal antibody targeted 20-residue peptide that protein. The was found be highly sensitive monospecific for on immunoblots. Although many immunological studies have described the absence or low expression in livers, present investigation, this not case. We immunoquantified apoprotein panel 28 livers...
Prototypic CYP3A4 inducers were tested in a pregnane X receptor (PXR) reporter gene assay, Fa2N-4 cells, HepaRG and primary human hepatocytes, along with negative controls, using mRNA activity endpoints, where appropriate. Over half of the compounds (14 24) identified as time-dependent inhibitors high mRNA/activity ratios (>10) consistent inhibition for such troleandomycin, ritonavir, verapamil. Induction response was compared between two donors; there an excellent correlation...
Recent guidance from the US Food and Drug Administration (USFDA) has advocated testing of time-dependent inhibition cytochrome P450 (CYP), which can be addressed by performing IC50 shift as well KI/kinact determinations.Direct (IC50, Ki) (IC50 shift, KI/kinact) assays were validated in human liver microsomes with liquid chromatography-tandem mass spectrometry (LC/MS/MS) analysis for following enzyme/substrate/inhibitor combinations: CYP1A2/phenacetin/alpha-naphthoflavone/furafylline,...
In vitro clearance assays are routinely conducted in drug discovery to predict vivo clearance, but low metabolic turnover compounds often difficult evaluate. Hepatocyte spheroids can be cultured for days, achieving higher turnover, have been hindered by limitations on cell number per well. Corning Elplasia microcavity 96-well microplates enable the culture of 79 hepatocyte this study, spheroid properties (size, function, longevity, culturing techniques) were assessed and optimized assays,...
Aflatoxin B1 (AFB1) is a highly hepatotoxic and hepatocarcinogenic secondary metabolite of the grain mold Aspergillus flavus related fungi. Indole-3-carbinol (I3C), found in cruciferous vegetables, can both inhibit promote AFB1-induced carcinogenesis. We have examined influence dietary treatment with I3C well-known Ah receptor agonist beta-naphthoflavone (BNF) on relative levels different cytochrome P-450 (CYP) isoforms known to metabolize AFB1 male Fischer 344 rats. After 7 days feeding...
Rapid screening for cytochrome P450 inhibitors is part of the current paradigm avoiding development drugs likely to give clinical pharmacokinetic drug-drug interactions and associated toxicities. We have developed microtiter plate-based, direct, fluorometric assays activities principal human drug-metabolizing enzymes, CYP1A2, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4, as well CYP2A6, which an important enzyme in environmental toxicology. These are rapid compatible with existing high-throughput...
This study describes the disposition and excretion of indole-3-carbinol (I3C), a natural dietary tumor modulator candidate chemopreventive agent, in male Fisher 344 rats after continuous or single oral administration. Steady-state urinary fecal were attained 40 112 hr, respectively, commencing exposure. These two routes accounted for approximately 75% administered dose, which 77% appeared feces. After 7 days 2,000 ppm I3C, mean 1,154 microM I3C eq was found liver, 17% present as extractable,...
Aflatoxin B1 (AFB1), a metabolite of the grain mold Aspergillus flavus, is potent hepatocarcinogen and widespread contaminant human food supplies. AFB1-induced tumors or preneoplastic lesions in experimental animals can be inhibited by cotreatment with several compounds, including indole-3-carbinol (I3C), component cruciferous vegetables, well-known Ah receptor agonist beta-naphthoflavone (BNF). This study examines influence these two agents on AFB1-glutathione detoxication pathway AFB1-DNA...
Permeability is a key factor driving the absorption of orally administered drugs. In early discovery, efficient evaluation permeability, particularly for compounds violating Lipinski's Rule 5, remains challenging. Addressing this, we established high-throughput method to measure experimental polar surface area (HT-EPSA) as an in vitro surrogate permeability. Compared earlier methods, HT-EPSA significantly reduces data acquisition time with enhanced sensitivity, selectivity, and quality....
The microsomal flavin-containing monooxygenases (FMO) represent a family of xenobiotic-metabolizing enzymes with distinct tissue- and species-specific patterns expression. Expression for two FMO isoforms (FMO1 FMO2) in rabbit was characterized by determining mRNA levels, protein levels catalytic activity male female liver, lung, kidney, esophagus, intestine, nasal mucosa (maxilloturbinates ethmoturbinates) gonadal tissue. Northern blot hybridization analyses performed cDNA probes each...
CYP3A4-mediated biotransformation of (<i>R</i>)-<i>N</i>-(1-(3-(4-ethoxyphenyl)-4-oxo-3,4-dihydropyrido[2,3-<i>d</i>]pyrimidin-2-yl)ethyl)-<i>N</i>-(pyridin-3-ylmethyl)-2-(4-(trifluoromethoxy)phenyl)acetamide (AMG 487) was previously shown to generate an inhibitory metabolite linked dose- and time-dependent pharmacokinetics in humans. Although vitro activity loss assays failed demonstrate CYP3A4 inhibition (TDI) with AMG 487, its M2 phenol readily produced TDI when remaining assessed using...
Breast cancer resistance protein (BCRP) and multidrug 2 (MRP2) can play a role in the absorption, distribution, metabolism, excretion of drugs, impacting on potential for drug–drug interactions. This study has characterized insect cell– mammalian cell–derived ABC-transporter–expressing membrane vesicle test systems validated methodologies evaluation candidate drugs as substrates or inhibitors BCRP MRP2.Concentration-dependent uptake ([3H]oestrone 3-sulfate, [3H]methotrexate,...
Cytochrome P450 (P450) induction is often considered a liability in drug development. Using calibration curve–based approaches, we assessed the parameters <i>R</i><sub>3</sub> (a term indicating amount of liver, expressed as ratio between 0 and 1), relative score, <i>C</i><sub>max</sub>/<i>EC</i><sub>50</sub>, area under curve (<i>AUC</i>)/<i>F</i><sub>2</sub> (the concentration causing 2-fold increase from baseline dose-response curve), derived concentration-response curves CYP3A4 mRNA...