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Cassar S, Huang X, Cole T. A high-throughput method for predicting drug effects on gut transit time using larval zebrafish. J Pharmacol Toxicol Methods 2015; 76:72-5. [PMID: 26311656 DOI: 10.1016/j.vascn.2015.08.156] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 05/18/2015] [Accepted: 08/19/2015] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Zebrafish are an attractive vertebrate model due to their small size, transparency through organogenesis, and high fecundity. The zebrafish gastrointestinal (GI) tract is similar to the mammalian GI tract in gene expression, nervous system control, and response to chemical challenges. GI intolerance is a common preclinical finding and can be a serious clinical safety concern. Mammalian GI liability tests are conducted at the expense of time, test article, and labor. We developed a high-throughput method to predict mammalian GI safety issues using larval zebrafish. METHODS Fluorescent food is fed to larval zebrafish (7 days post fertilization). After feeding, larvae are placed individually into wells of a 96-well plate and dosed with test compounds. Fluorescence is measured from the bottom of the wells repeatedly over the course of 24h and thus fecal accumulation is tracked over time. The area under the curve is compared between treated and vehicle-treated groups. RESULTS Drugs with established clinical GI effects significantly impacted zebrafish GI transit time as measured by this method; tegaserod and metoclopramide accelerated transit time, while atropine and amitriptyline slowed transit time. This method is sensitive enough to reflect dose-level associated effects as demonstrated using atropine. Using a suite of 24 compounds with known (positive or negative) mammalian GI effects, we characterized this method as having a high positive predictive value. DISCUSSION Here we present an efficient assay for predicting mammalian GI transit liabilities using larval zebrafish. With this assay, an investigator can evaluate dozens of compounds in a single day using very little amount of each test article. As such, safe drug candidates can be prioritized for mammalian testing, which expedites the discovery process and provides 3 Rs impact.
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Intracellular concentrations determine the cytotoxicity of adefovir, cidofovir and tenofovir. Toxicol In Vitro 2015; 29:251-8. [PMID: 25448811 DOI: 10.1016/j.tiv.2014.10.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 09/27/2014] [Accepted: 10/22/2014] [Indexed: 01/01/2023]
Abstract
Lack of in vitro to in vivo translation is a major challenge in safety prediction during early drug discovery.One of the most common in vitro assays to evaluate the probability of a compound to cause adverse effects is a cytotoxicity assay. Cytotoxicity of a compound is often measured by dose–response curves assuming the administered doses and intracellular exposures are equal at the time of measurement.However, this may not be true for compounds with low membrane permeability or those which are substrates for drug transporters as intracellular concentrations are determined both by passive permeability and active uptake through drug transporters. We show here that three antiviral drugs, adefovir, cidofovir and tenofovir exhibit significantly increased cytotoxicity in HEK293 cells transfected with organic anion transporter (OAT) 1 and 3 compared to a lack of cytotoxicity in HEK293 wildtype cells. A further look at the media and intracellular drug concentrations showed that 24 h after dosing, all three drugs had higher intracellular drug concentrations than that of media in the HEK-OAT1 cells whereas the intracellular drug concentrations in the wildtype cells were much lower than the administered doses. Comparing cytotoxicity IC(50) values of adefovir, cidofovir and tenofovir based on administered doses and measured intracellular concentrations in HEK-OAT1 cells revealed that intracellular drug concentrations have significant impact on calculated IC(50) values. Tenofovir showed much less intrinsic cytotoxicity than adefovir and cidofovir using intracellular concentrations rather than media concentration. Our data suggest that for low permeable drugs or drugs that are substrates for drug transporters, the choice of cellular model is critical for providing an accurate determination of cytotoxicity.
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103
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Bradford AB, McNutt PM. Importance of being Nernst: Synaptic activity and functional relevance in stem cell-derived neurons. World J Stem Cells 2015; 7:899-921. [PMID: 26240679 PMCID: PMC4515435 DOI: 10.4252/wjsc.v7.i6.899] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 02/28/2015] [Accepted: 05/11/2015] [Indexed: 02/06/2023] Open
Abstract
Functional synaptogenesis and network emergence are signature endpoints of neurogenesis. These behaviors provide higher-order confirmation that biochemical and cellular processes necessary for neurotransmitter release, post-synaptic detection and network propagation of neuronal activity have been properly expressed and coordinated among cells. The development of synaptic neurotransmission can therefore be considered a defining property of neurons. Although dissociated primary neuron cultures readily form functioning synapses and network behaviors in vitro, continuously cultured neurogenic cell lines have historically failed to meet these criteria. Therefore, in vitro-derived neuron models that develop synaptic transmission are critically needed for a wide array of studies, including molecular neuroscience, developmental neurogenesis, disease research and neurotoxicology. Over the last decade, neurons derived from various stem cell lines have shown varying ability to develop into functionally mature neurons. In this review, we will discuss the neurogenic potential of various stem cells populations, addressing strengths and weaknesses of each, with particular attention to the emergence of functional behaviors. We will propose methods to functionally characterize new stem cell-derived neuron (SCN) platforms to improve their reliability as physiological relevant models. Finally, we will review how synaptically active SCNs can be applied to accelerate research in a variety of areas. Ultimately, emphasizing the critical importance of synaptic activity and network responses as a marker of neuronal maturation is anticipated to result in in vitro findings that better translate to efficacious clinical treatments.
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Silveira JEPS, Pereda MCV, Nogueira C, Dieamant G, Cesar CKM, Assanome KM, Silva MS, Torello CO, Queiroz MLS, Eberlin S. Preliminary safety assessment of C-8 xylitol monoester and xylitol phosphate esters. Int J Cosmet Sci 2015; 38:41-51. [PMID: 26193758 DOI: 10.1111/ics.12262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 06/10/2015] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Most of the cosmetic compounds with preservative properties available in the market pose some risks concerning safety, such as the possibility of causing sensitization. Due to the fact that there are few options, the proper development of new molecules with this purpose is needed. Xylitol is a natural sugar, and the antimicrobial properties of xylitol-derived compounds have already been described in the literature. C-8 xylitol monoester and xylitol phosphate esters may be useful for the development of skincare products. As an initial screen for safety of chemicals, the combination of in silico methods and in vitro testing can aid in prioritizing resources in toxicological investigations while reducing the ethical and monetary costs that are related to animal and human testing. This study was designed to evaluate the safety of C-8 xylitol monoester and xylitol phosphate esters regarding carcinogenicity, mutagenicity, skin and eye irritation/corrosion and sensitization through alternative methods. METHODS For the initial safety assessment, quantitative structure-activity relationship methodology was used. The prediction of the parameters carcinogenicity/mutagenicity, skin and eye irritation/corrosion and sensitization was generated from the chemical structure. The analysis also comprised physical-chemical properties, Cramer rules, threshold of toxicological concern and Michael reaction. In silico results of candidate molecules were compared to 19 compounds with preservative properties that are available in the market. Additionally, in vitro tests (Ames test for mutagenicity, cytotoxicity and phototoxicity tests and hen's egg test--chorioallantoic membrane for irritation) were performed to complement the evaluation. RESULTS In silico evaluation of both molecules presented no structural alerts related to eye and skin irritation, corrosion and sensitization, but some alerts for micronucleus and carcinogenicity were detected. However, by comparison, C-8 xylitol monoester, xylitol phosphate esters showed similar or better results than the compounds available in the market. Concerning experimental data, phototoxicity and mutagenicity results were negative. As expected for compounds with preservative activity, xylitol-derived substances presented positive result in cytotoxicity test. In hen's egg test, both molecules were irritants. CONCLUSION Our results suggested that xylitol-derived compounds appear to be suitable candidates for preservative systems in cosmetics.
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Affiliation(s)
- J E P S Silveira
- Department of Pharmacology/Hemocenter, Faculty of Medical Science, State University of Campinas (Unicamp), Campinas, SP, Brazil
| | - M C V Pereda
- Research and Development Department, Chemyunion Química Ltda, Sorocaba, SP, Brazil
| | - C Nogueira
- Research and Development Department, Chemyunion Química Ltda, Sorocaba, SP, Brazil
| | - G Dieamant
- Department of Pharmacology/Hemocenter, Faculty of Medical Science, State University of Campinas (Unicamp), Campinas, SP, Brazil
| | - C K M Cesar
- Research and Development Department, Chemyunion Química Ltda, Sorocaba, SP, Brazil
| | | | - M S Silva
- Department of Pharmacology/Hemocenter, Faculty of Medical Science, State University of Campinas (Unicamp), Campinas, SP, Brazil
| | - C O Torello
- Department of Pharmacology/Hemocenter, Faculty of Medical Science, State University of Campinas (Unicamp), Campinas, SP, Brazil
| | - M L S Queiroz
- Department of Pharmacology/Hemocenter, Faculty of Medical Science, State University of Campinas (Unicamp), Campinas, SP, Brazil
| | - S Eberlin
- Department of Pharmacology/Hemocenter, Faculty of Medical Science, State University of Campinas (Unicamp), Campinas, SP, Brazil
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Vernetti LA, Senutovitch N, Boltz R, DeBiasio R, Shun TY, Gough A, Taylor DL. A human liver microphysiology platform for investigating physiology, drug safety, and disease models. Exp Biol Med (Maywood) 2015. [PMID: 26202373 DOI: 10.1177/1535370215592121] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
This paper describes the development and characterization of a microphysiology platform for drug safety and efficacy in liver models of disease that includes a human, 3D, microfluidic, four-cell, sequentially layered, self-assembly liver model (SQL-SAL); fluorescent protein biosensors for mechanistic readouts; as well as a microphysiology system database (MPS-Db) to manage, analyze, and model data. The goal of our approach is to create the simplest design in terms of cells, matrix materials, and microfluidic device parameters that will support a physiologically relevant liver model that is robust and reproducible for at least 28 days for stand-alone liver studies and microfluidic integration with other organs-on-chips. The current SQL-SAL uses primary human hepatocytes along with human endothelial (EA.hy926), immune (U937) and stellate (LX-2) cells in physiological ratios and is viable for at least 28 days under continuous flow. Approximately, 20% of primary hepatocytes and/or stellate cells contain fluorescent protein biosensors (called sentinel cells) to measure apoptosis, reactive oxygen species (ROS) and/or cell location by high content analysis (HCA). In addition, drugs, drug metabolites, albumin, urea and lactate dehydrogenase (LDH) are monitored in the efflux media. Exposure to 180 μM troglitazone or 210 μM nimesulide produced acute toxicity within 2-4 days, whereas 28 μM troglitazone produced a gradual and much delayed toxic response over 21 days, concordant with known mechanisms of toxicity, while 600 µM caffeine had no effect. Immune-mediated toxicity was demonstrated with trovafloxacin with lipopolysaccharide (LPS), but not levofloxacin with LPS. The SQL-SAL exhibited early fibrotic activation in response to 30 nM methotrexate, indicated by increased stellate cell migration, expression of alpha-smooth muscle actin and collagen, type 1, alpha 2. Data collected from the in vitro model can be integrated into a database with access to related chemical, bioactivity, preclinical and clinical information uploaded from external databases for constructing predictive models.
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Affiliation(s)
- Lawrence A Vernetti
- University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA University of Pittsburgh Dept. of Computational & Systems Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Nina Senutovitch
- University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA University of Pittsburgh Dept. of Computational & Systems Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Robert Boltz
- University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA University of Pittsburgh Dept. of Computational & Systems Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Richard DeBiasio
- University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Tong Ying Shun
- University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Albert Gough
- University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA University of Pittsburgh Dept. of Computational & Systems Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - D Lansing Taylor
- University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA University of Pittsburgh Dept. of Computational & Systems Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA
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Shirakawa M, Sekine S, Tanaka A, Horie T, Ito K. Metabolic activation of hepatotoxic drug (benzbromarone) induced mitochondrial membrane permeability transition. Toxicol Appl Pharmacol 2015; 288:12-8. [PMID: 26148448 DOI: 10.1016/j.taap.2015.06.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 06/22/2015] [Accepted: 06/26/2015] [Indexed: 12/23/2022]
Abstract
The risk of drug-induced liver injury (DILI) is of great concern to the pharmaceutical industry. It is well-known that metabolic activation of drugs to form toxic metabolites (TMs) is strongly associated with DILI onset. Drug-induced mitochondrial dysfunction is also strongly associated with increased risk of DILI. However, it is difficult to determine the target of TMs associated with exacerbation of DILI because of difficulties in identifying and purifying TMs. In this study, we propose a sequential in vitro assay system to assess TM formation and their ability to induce mitochondrial permeability transition (MPT) in a one-pot process. In this assay system, freshly-isolated rat liver mitochondria were incubated with reaction solutions of 44 test drugs preincubated with liver microsomes in the presence or absence of NADPH; then, NADPH-dependent MPT pore opening was assessed as mitochondrial swelling. In this assay system, several hepatotoxic drugs, including benzbromarone (BBR), significantly induced MPT in a NADPH-dependent manner. We investigated the rationality of using BBR as a model drug, since it showed the most prominent MPT in our assay system. Both the production of a candidate toxic metabolite of BBR (1',6-(OH)2 BBR) and NADPH-dependent MPT were inhibited by several cytochrome P450 (CYP) inhibitors (clotrimazole and SKF-525A, 100μM). In summary, this assay system can be used to evaluate comprehensive metabolite-dependent MPT without identification or purification of metabolites.
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Affiliation(s)
- Maho Shirakawa
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Shuichi Sekine
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Ayaka Tanaka
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Toshiharu Horie
- Faculty of Pharmaceutical Sciences, Teikyo Heisei University, Tokyo, Japan
| | - Kousei Ito
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan.
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Moulin F, Flint O. In VitroModels for the Prediction of Drug-Induced Liver Injury in Lead Discovery. ACTA ACUST UNITED AC 2015. [DOI: 10.1002/9783527673643.ch07] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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108
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Nallathamby PD, Mortensen NP, Palko HA, Malfatti M, Smith C, Sonnett J, Doktycz MJ, Gu B, Roeder RK, Wang W, Retterer ST. New surface radiolabeling schemes of super paramagnetic iron oxide nanoparticles (SPIONs) for biodistribution studies. NANOSCALE 2015; 7:6545-55. [PMID: 25790032 PMCID: PMC4847546 DOI: 10.1039/c4nr06441k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Nanomaterial based drug delivery systems allow for the independent tuning of the surface chemical and physical properties that affect their biodistribution in vivo and the therapeutic payloads that they are intended to deliver. Additionally, the added therapeutic and diagnostic value of their inherent material properties often provides extra functionality. Iron based nanomaterials with their magnetic properties and easily tailorable surface chemistry are of particular interest as model systems. In this study the core radius of the iron oxide nanoparticles (NPs) was 14.08 ± 3.92 nm while the hydrodynamic radius of the NPs, as determined by Dynamic Light Scattering (DLS), was between 90-110 nm. In this study, different approaches were explored to create radiolabeled NPs that are stable in solution. The NPs were functionalized with polycarboxylate or polyamine surface functional groups. Polycarboxylate functionalized NPs had a zeta potential of -35 mV and polyamine functionalized NPs had a zeta potential of +40 mV. The polycarboxylate functionalized NPs were chosen for in vivo biodistribution studies and hence were radiolabeled with (14)C, with a final activity of 0.097 nCi mg(-1) of NPs. In chronic studies, the biodistribution profile is tracked using low level radiolabeled proxies of the nanoparticles of interest. Conventionally, these radiolabeled proxies are chemically similar but not chemically identical to the non-radiolabeled NPs of interest. This study is novel as different approaches were explored to create radiolabeled NPs that are stable, possess a hydrodynamic radius of <100 nm and most importantly they exhibit an identical surface chemical functionality as their non-radiolabeled counterparts. Identical chemical functionality of the radiolabeled probes to the non-radiolabeled probes was an important consideration to generate statistically similar biodistribution data sets using multiple imaging and detection techniques. The radiolabeling approach described here is applicable to the synthesis of a large class of nanomaterials with multiple core and surface functionalities. This work combined with the biodistribution data suggests that the radiolabeling schemes carried out in this study have broad implications for use in pharmacokinetic studies for a variety of nanomaterials.
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Affiliation(s)
- Prakash D. Nallathamby
- Battelle Center for Fundamental and Applied Systems Toxicology, Battelle Memorial Institute, Columbus, OH 43201, USA
- Biological and Environmental Sciences Divisions, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- Department of Aerospace and Mechanical Engineering; Bioengineering Graduate Program, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Ninell P. Mortensen
- Biological and Environmental Sciences Divisions, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Heather A. Palko
- Battelle Center for Fundamental and Applied Systems Toxicology, Battelle Memorial Institute, Columbus, OH 43201, USA
- Biosciences and Biotechnology Division, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Mike Malfatti
- Biosciences and Biotechnology Division, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Catherine Smith
- Battelle Center for Fundamental and Applied Systems Toxicology, Battelle Memorial Institute, Columbus, OH 43201, USA
| | - James Sonnett
- Battelle Center for Fundamental and Applied Systems Toxicology, Battelle Memorial Institute, Columbus, OH 43201, USA
| | - Mitchel J. Doktycz
- Biological and Environmental Sciences Divisions, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Baohua Gu
- Biological and Environmental Sciences Divisions, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Ryan K. Roeder
- Department of Aerospace and Mechanical Engineering; Bioengineering Graduate Program, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Wei Wang
- Biological and Environmental Sciences Divisions, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Scott T. Retterer
- Biological and Environmental Sciences Divisions, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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Kelly C, Lawlor C, Burke C, Barlow JW, Ramsey JM, Jefferies C, Cryan SA. High-throughput methods for screening liposome–macrophage cell interaction. J Liposome Res 2014; 25:211-221. [DOI: 10.3109/08982104.2014.987785] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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110
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Cachat E, Liu W, Hohenstein P, Davies JA. A library of mammalian effector modules for synthetic morphology. J Biol Eng 2014; 8:26. [PMID: 25478005 PMCID: PMC4255936 DOI: 10.1186/1754-1611-8-26] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 10/02/2014] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND In mammalian development, the formation of most tissues is achieved by a relatively small repertoire of basic morphogenetic events (e.g. cell adhesion, locomotion, apoptosis, etc.), permutated in various sequences to form different tissues. Together with cell differentiation, these mechanisms allow populations of cells to organize themselves into defined geometries and structures, as simple embryos develop into complex organisms. The control of tissue morphogenesis by populations of engineered cells is a potentially very powerful but neglected aspect of synthetic biology. RESULTS We have assembled a modular library of synthetic morphogenetic driver genes to control (separately) mammalian cell adhesion, locomotion, fusion, proliferation and elective cell death. Here we describe this library and demonstrate its use in the T-REx-293 human cell line to induce each of these desired morphological behaviours on command. CONCLUSIONS Building on from the simple test systems described here, we want to extend engineered control of morphogenetic cell behaviour to more complex 3D structures that can inform embryologists and may, in the future, be used in surgery and regenerative medicine, making synthetic morphology a powerful tool for developmental biology and tissue engineering.
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Affiliation(s)
- Elise Cachat
- University of Edinburgh, Centre for Integrative Physiology, Hugh Robson Building, George Square, Edinburgh, EH8 9XD UK
| | - Weijia Liu
- University of Edinburgh, Centre for Integrative Physiology, Hugh Robson Building, George Square, Edinburgh, EH8 9XD UK
| | - Peter Hohenstein
- The Roslin Institute, University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG UK
| | - Jamie A Davies
- University of Edinburgh, Centre for Integrative Physiology, Hugh Robson Building, George Square, Edinburgh, EH8 9XD UK
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Nam KH, Smith AST, Lone S, Kwon S, Kim DH. Biomimetic 3D Tissue Models for Advanced High-Throughput Drug Screening. ACTA ACUST UNITED AC 2014; 20:201-15. [PMID: 25385716 DOI: 10.1177/2211068214557813] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Indexed: 12/13/2022]
Abstract
Most current drug screening assays used to identify new drug candidates are 2D cell-based systems, even though such in vitro assays do not adequately re-create the in vivo complexity of 3D tissues. Inadequate representation of the human tissue environment during a preclinical test can result in inaccurate predictions of compound effects on overall tissue functionality. Screening for compound efficacy by focusing on a single pathway or protein target, coupled with difficulties in maintaining long-term 2D monolayers, can serve to exacerbate these issues when using such simplistic model systems for physiological drug screening applications. Numerous studies have shown that cell responses to drugs in 3D culture are improved from those in 2D, with respect to modeling in vivo tissue functionality, which highlights the advantages of using 3D-based models for preclinical drug screens. In this review, we discuss the development of microengineered 3D tissue models that accurately mimic the physiological properties of native tissue samples and highlight the advantages of using such 3D microtissue models over conventional cell-based assays for future drug screening applications. We also discuss biomimetic 3D environments, based on engineered tissues as potential preclinical models for the development of more predictive drug screening assays for specific disease models.
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Affiliation(s)
- Ki-Hwan Nam
- Department of Bioengineering, University of Washington, Seattle, WA, USA Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea Center for Analytical Instrumentation Development, The Korea Basic Science Institute, Deajeon, Republic of Korea
| | - Alec S T Smith
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Saifullah Lone
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea
| | - Sunghoon Kwon
- Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea
| | - Deok-Ho Kim
- Department of Bioengineering, University of Washington, Seattle, WA, USA Center for Cardiovascular Biology, University of Washington, Seattle, WA, USA Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
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Lan J, Gou N, Gao C, He M, Gu AZ. Comparative and mechanistic genotoxicity assessment of nanomaterials via a quantitative toxicogenomics approach across multiple species. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:12937-45. [PMID: 25338269 PMCID: PMC4224493 DOI: 10.1021/es503065q] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 10/02/2014] [Accepted: 10/03/2014] [Indexed: 05/19/2023]
Abstract
This study reports a comparative and mechanistic genotoxicity assessment of four engineered nanomaterials (ENMs) across three species, including E. coli, yeast, and human cells, with the aim to reveal the distinct potential genotoxicity mechanisms among the different nanomaterials and their association with physiochemical features. Both the conventional phenotypic alkaline comet test and the newly developed quantitative toxicogenomics assay, that detects and quantifies molecular level changes in the regulation of six DNA damage repair pathways, were employed. The proposed molecular endpoints derived from the toxicogenomics assays, namely TELI (Transcriptional Effect Level Index) and PELI (Protein Effect Level Index), correlated well with the phenotypic DNA damage endpoints from comet tests, suggesting that the molecular genotoxicity assay is suitable for genotoxicity detection. Temporal altered gene or protein expression profiles revealed various potential DNA damage types and relevant genotoxic mechanisms induced by the tested ENMs. nTiO2_a induced a wide spectrum of DNA damage consistently across three species. Three carbon-based ENMs, namely carbon black, single wall carbon nanotube (SWCNT) and fullerene, exhibited distinct, species and ENM property-dependent DNA damage mechanisms. All carbon based ENMs induced relatively weak DNA damage repair response in E. coli, but more severe DNA double strand break in eukaryotes. The differences in cellular structure and defense systems among prokaryotic and eukaryotic species lead to distinct susceptibility and mechanisms for ENM uptake and, thus, varying DNA damages and repair responses. The observation suggested that eukaryotes, especially mammalian cells, are likely more susceptible to genotoxicity than prokaryotes in the ecosystem when exposed to these ENMs.
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Affiliation(s)
- Jiaqi Lan
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Na Gou
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Ce Gao
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Miao He
- Environmental
simulation and pollution control (ESPC) State Key Joint Laboratory,
School of Environment, Tsinghua University, Beijing, 100084, People’s Republic of China
| | - April Z. Gu
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
- Tel.: + 1-617−373−3631; e-mail:
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Mahto SK, Charwat V, Ertl P, Rothen-Rutishauser B, Rhee SW, Sznitman J. Microfluidic platforms for advanced risk assessments of nanomaterials. Nanotoxicology 2014; 9:381-95. [DOI: 10.3109/17435390.2014.940402] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Sanjeev Kumar Mahto
- Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel,
| | - Verena Charwat
- BioSensor Technologies, Austrian Institute of Technology (AIT), Vienna, Austria,
- Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse, Vienna, Austria,
| | - Peter Ertl
- BioSensor Technologies, Austrian Institute of Technology (AIT), Vienna, Austria,
| | | | - Seog Woo Rhee
- Department of Chemistry, College of Natural Sciences, Kongju National University, Kongju, South Korea
| | - Josué Sznitman
- Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel,
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Kwapiszewska K, Michalczuk A, Rybka M, Kwapiszewski R, Brzózka Z. A microfluidic-based platform for tumour spheroid culture, monitoring and drug screening. LAB ON A CHIP 2014; 14:2096-104. [PMID: 24800721 DOI: 10.1039/c4lc00291a] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The development of novel cellular models that can replace animals in preclinical trials of drug candidates is one of the major goals of cell engineering. Current in vitro screening methods hardly correspond with the in vivo situation, whereas there is a lack of assays for more accurate cell culture models. Therefore, development of automated assays for 3D cell culture models is urgently required. In this work, we present a SpheroChip system: a microfluidic-based platform for long-term 3D cell culture and analysis. The system is compatible with commercially available microplate readers and provides continuous, in situ monitoring of tumour spheroids cultured on a chip. The microfluidic chip consists of cell culture microchambers and hemispherical microwells connected with a concentration gradient generator. HT-29 and Hep-G2 cells were successfully cultured as tumour spheroids in the SpheroChip, and metabolic activity of cells was monitored for up to two weeks by in situ fluorimetric measurements. Cellular response to an anticancer drug was observed using the SpheroChip. The experimental setup provided the unique possibility of observing dynamic changes in metabolic activity of one culture during sequencing days after drug dosage. According to this new approach, unknown phenomena of cellular response to the anticancer drug were observed, such as increase of metabolic activity shortly after drug dosage. Moreover, the influence of a second dose of a drug was evaluated. The SpheroChip system can be used by researchers working on drug screening, evaluation of anticancer procedures and chemoresistance phenomena.
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Affiliation(s)
- K Kwapiszewska
- Institute of Biotechnology, Department of Microbioanalytics, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
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115
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Germano D, Uteng M, Pognan F, Chibout SD, Wolf A. Determination of liver specific toxicities in rat hepatocytes by high content imaging during 2-week multiple treatment. Toxicol In Vitro 2014; 30:79-94. [PMID: 24933330 DOI: 10.1016/j.tiv.2014.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 05/13/2014] [Accepted: 05/19/2014] [Indexed: 12/26/2022]
Abstract
DILI is a major safety issue during drug development and one of the leading causes for market withdrawal. Despite many efforts made in the past, the prediction of DILI using in vitro models remains very unreliable. In the present study, the well-established hepatocyte Collagen I-Matrigel™ sandwich culture was used, mimicking chronic drug treatment after multiple incubations for 14 days. Ten drugs associated with different types of specific preclinical and clinical liver injury were evaluated at non-cytotoxic concentrations. Mrp2-mediated transport, intracellular accumulation of neutral lipids and phospholipids were selected as functional endpoints by using Cellomics™ Arrayscan® technology and assessed at five timepoints (day 1, 3, 7, 10, 14). Liver specific functional impairments after drug treatment were enhanced over time and could be monitored by HCI already after few days and before cytotoxicity. Phospholipidosis-inducing drugs Chlorpromazine and Amiodarone displayed the same response as in vivo. Cyclosporin A, Chlorpromazine, and Troglitazone inhibited Mrp2-mediated biliary transport, correlating with in vivo findings. Steatosis remained difficult to be reproduced under the current in vitro testing conditions, resulting into false negative and positive responses. The present results suggest that the repeated long-term treatment of rat hepatocytes in the Collagen I-Matrigel™ sandwich configuration might be a suitable tool for safety profiling of the potential to induce phospholipidosis and impair Mrp2-mediated transport processes, but not to predict steatosis.
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Affiliation(s)
- Davide Germano
- Discovery and Investigative Safety, Preclinical Safety, Novartis Institutes for Biomedical Research, CH-4057 Basel, Switzerland
| | - Marianne Uteng
- Discovery and Investigative Safety, Preclinical Safety, Novartis Institutes for Biomedical Research, CH-4057 Basel, Switzerland
| | - Francois Pognan
- Discovery and Investigative Safety, Preclinical Safety, Novartis Institutes for Biomedical Research, CH-4057 Basel, Switzerland
| | - Salah-Dine Chibout
- Discovery and Investigative Safety, Preclinical Safety, Novartis Institutes for Biomedical Research, CH-4057 Basel, Switzerland
| | - Armin Wolf
- Discovery and Investigative Safety, Preclinical Safety, Novartis Institutes for Biomedical Research, CH-4057 Basel, Switzerland.
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Gordon CP, Hizartzidis L, Tarleton M, Sakoff JA, Gilbert J, Campbell BE, Gasser RB, McCluskey A. Discovery of acrylonitrile-based small molecules active against Haemonchus contortus. MEDCHEMCOMM 2014. [DOI: 10.1039/c3md00255a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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118
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Lapchak PA. Emerging Therapies: Pleiotropic Multi-target Drugs to Treat Stroke Victims. Transl Stroke Res 2013; 2:129-35. [PMID: 21666853 DOI: 10.1007/s12975-011-0074-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Paul A Lapchak
- Translational Research, Cedars-Sinai Medical Center, Department of Neurology, Burns and Allen Research Institute, Davis Research Building, Room D-2091, 110 N. George Burns Road, Los Angeles, CA 90048, USA
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Lapchak PA, Schubert DR, Maher PA. De-Risking of Stilbazulenyl Nitrone (STAZN), a Lipophilic Nitrone to Treat Stroke Using a Unique Panel of In Vitro Assays. Transl Stroke Res 2013; 2:209-17. [PMID: 22003372 DOI: 10.1007/s12975-011-0071-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In the present study, we used a comprehensive panel of in vitro assays to evaluate the efficacy and safety of stilbazulenyl nitrone (STAZN) as a lead compound to treat acute ischemic stroke. First, we measured neuroprotection in vitro using two different HT22 hippocampal nerve cell assays. Secondly, to de-risk drug development, we used CeeTox analysis with the H4IIE rat hepatoma cell line to determine the acute toxicity profile of STAZN. Third, STAZN was tested in microsomes from four species for measures of metabolic stability. Last, we determined the Ames test genotoxicity profile of STAZN using Salmonella typhimurium TA989 and TA100. In vitro, STAZN was neuroprotective against toxicity induced by iodoacetic acid, and oxytosis-induced glutathione depletion was initiated by glutamate, with an EC(50) value of 1-5 μM. Secondly, using CeeTox analysis, the estimated C(Tox) value (i.e., sustained concentration expected to produce toxicity in a rat 14-day repeat dose study) for STAZN was calculated to be 260 μM. Third, the half-life of STAZN in humans, dogs, and rats was 60-78 min. Last, the genotoxicity profile showed that STAZN did not induce bacterial colony growth under any conditions tested, indicating the lack of mutagenicity with this compound. STAZN appears to be a multi-target neuroprotective compound that has an excellent safety profile in both the CeeTox and Ames mutagenicity assays. STAZN may have significant potential as a novel neuroprotective agent to treat stroke and should be pursued in clinically relevant embolic stroke models.
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Affiliation(s)
- Paul A Lapchak
- Department of Neurology, Cedars-Sinai Medical Center, Davis Research Building, D-2091, 110 N. George Burns Road, Los Angeles, CA 90048, USA
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Lapchak PA, McKim JM. CeeTox™ Analysis of CNB-001 a Novel Curcumin-Based Neurotrophic/Neuroprotective Lead Compound to Treat Stroke: Comparison with NXY-059 and Radicut. Transl Stroke Res 2013; 2:51-9. [PMID: 21494575 DOI: 10.1007/s12975-010-0034-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In the present study, we used a comprehensive cellular toxicity (CeeTox) analysis panel to determine the toxicity profile for CNB-001 [4-((1E)-2-(5-(4-hydroxy-3-methoxystyryl-)-1-phenyl-1H-pyrazoyl-3-yl)vinyl)-2-methoxy-phenol)], which is a hybrid molecule created by combining cyclohexyl bisphenol A, a molecule with neurotrophic activity and curcumin, a spice with neuro-protective activity. CNB-001 is a lead development compound since we have recently shown that CNB-001 has significant preclinical efficacy both in vitro and in vivo. In this study, we compared the CeeTox profile of CNB-001 with two neuroprotective molecules that have been clinically tested for efficacy: the hydrophilic free radical spin trap agent NXY-059 and the hydrophobic free radical scavenger edaravone (Radicut). CeeTox analyses using a rat hepatoma cell line (H4IIE) resulted in estimated C(Tox) value (i.e., sustained concentration expected to produce toxicity in a rat 14-day repeat dose study) of 42 μM for CNB-001 compared with >300 μM for both NXY-059 and Radicut. The CeeTox panel suggests that CNB-001 produces some adverse effects on cellular adenosine triphosphate content, membrane toxicity, glutathione content, and cell mass (or number), but only with high concentrations of the drug. After a 24-h exposure, the drug concentration that produced a half-maximal response (TC(50)) on the measures noted above ranges from 55 to 193 μM. Moreover, all CNB-001-induced changes in the markers were coincident with loss of cell number, prior to acute cell death as measured by membrane integrity, suggesting a cytostatic effect of CNB-001. NXY-059 and Radicut did not have acute toxic effects on H4IIE cells. We also found that CNB-001 resulted in an inhibition of ethoxyresorufin-o-deethylase activity, indicating that the drug may affect cytochrome P4501A activity and that CNB-001 was metabolically unstable using a rat microsome assay system. For CNB-001, an estimated in vitro efficacy/toxicity ratio is 183-643-fold, suggesting that there is a significant therapeutic safety window for CNB-001 and that it should be further developed as a novel neuroprotective agent to treat stroke.
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Affiliation(s)
- Paul A Lapchak
- Department of Neurology, Cedars-Sinai Medical Center, Burns and Allen Research Institute, 110 N. George Burns Road, D-2091, Los Angeles, CA 90048, USA
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121
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Atienzar FA, Novik EI, Gerets HH, Parekh A, Delatour C, Cardenas A, MacDonald J, Yarmush ML, Dhalluin S. Predictivity of dog co-culture model, primary human hepatocytes and HepG2 cells for the detection of hepatotoxic drugs in humans. Toxicol Appl Pharmacol 2013; 275:44-61. [PMID: 24333257 DOI: 10.1016/j.taap.2013.11.022] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 11/20/2013] [Accepted: 11/27/2013] [Indexed: 12/19/2022]
Abstract
Drug induced liver injury (DILI) is a major cause of attrition during early and late stage drug development. Consequently, there is a need to develop better in vitro primary hepatocyte models from different species for predicting hepatotoxicity in both animals and humans early in drug development. Dog is often chosen as the non-rodent species for toxicology studies. Unfortunately, dog in vitro models allowing long term cultures are not available. The objective of the present manuscript is to describe the development of a co-culture dog model for predicting hepatotoxic drugs in humans and to compare the predictivity of the canine model along with primary human hepatocytes and HepG2 cells. After rigorous optimization, the dog co-culture model displayed metabolic capacities that were maintained up to 2 weeks which indicates that such model could be also used for long term metabolism studies. Most of the human hepatotoxic drugs were detected with a sensitivity of approximately 80% (n=40) for the three cellular models. Nevertheless, the specificity was low approximately 40% for the HepG2 cells and hepatocytes compared to 72.7% for the canine model (n=11). Furthermore, the dog co-culture model showed a higher superiority for the classification of 5 pairs of close structural analogs with different DILI concerns in comparison to both human cellular models. Finally, the reproducibility of the canine system was also satisfactory with a coefficient of correlation of 75.2% (n=14). Overall, the present manuscript indicates that the dog co-culture model may represent a relevant tool to perform chronic hepatotoxicity and metabolism studies.
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Affiliation(s)
- Franck A Atienzar
- UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l'Alleud, Belgium.
| | - Eric I Novik
- Hμrel Corporation, 675 U.S. Highway 1, North Brunswick, NJ 08902, USA
| | - Helga H Gerets
- UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l'Alleud, Belgium
| | - Amit Parekh
- Hμrel Corporation, 675 U.S. Highway 1, North Brunswick, NJ 08902, USA
| | - Claude Delatour
- UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l'Alleud, Belgium
| | - Alvaro Cardenas
- UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l'Alleud, Belgium
| | - James MacDonald
- Chrysalis Pharma Consulting, LLC, 385 Route 24, Suite 1G, Chester, NJ 07930, USA
| | - Martin L Yarmush
- Department of Biomedical Engineering, Rutgers University, Piscataway, NJ 08854, USA
| | - Stéphane Dhalluin
- UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l'Alleud, Belgium
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Lapchak PA. Fast neuroprotection (fast-NPRX) for acute ischemic stroke victims: the time for treatment is now. Transl Stroke Res 2013; 4:704-9. [PMID: 24323424 DOI: 10.1007/s12975-013-0303-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 10/23/2013] [Indexed: 01/25/2023]
Affiliation(s)
- Paul A Lapchak
- Department of Neurology and Neurosurgery, Cedars-Sinai Medical Center, Advanced Health Sciences Pavilion, Rm 8305, 127 S. San Vicente Blvd, Los Angeles, CA, 90048, USA,
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Pereira-Fernandes A, Demaegdt H, Vandermeiren K, Hectors TLM, Jorens PG, Blust R, Vanparys C. Evaluation of a screening system for obesogenic compounds: screening of endocrine disrupting compounds and evaluation of the PPAR dependency of the effect. PLoS One 2013; 8:e77481. [PMID: 24155963 PMCID: PMC3796469 DOI: 10.1371/journal.pone.0077481] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 09/02/2013] [Indexed: 12/21/2022] Open
Abstract
Recently the environmental obesogen hypothesis has been formulated, proposing a role for endocrine disrupting compounds (EDCs) in the development of obesity. To evaluate this hypothesis, a screening system for obesogenic compounds is urgently needed. In this study, we suggest a standardised protocol for obesogen screening based on the 3T3-L1 cell line, a well-characterised adipogenesis model, and direct fluorescent measurement using Nile red lipid staining technique. In a first phase, we characterised the assay using the acknowledged obesogens rosiglitazone and tributyltin. Based on the obtained dose-response curves for these model compounds, a lipid accumulation threshold value was calculated to ensure the biological relevance and reliability of statistically significant effects. This threshold based method was combined with the well described strictly standardized mean difference (SSMD) method for classification of non-, weak- or strong obesogenic compounds. In the next step, a range of EDCs, used in personal and household care products (parabens, musks, phthalates and alkylphenol compounds), were tested to further evaluate the obesogenicity screening assay for its discriminative power and sensitivity. Additionally, the peroxisome proliferator activated receptor γ (PPARγ) dependency of the positive compounds was evaluated using PPARγ activation and antagonist experiments. Our results showed the adipogenic potential of all tested parabens, several musks and phthalate compounds and bisphenol A (BPA). PPARγ activation was associated with adipogenesis for parabens, phthalates and BPA, however not required for obesogenic effects induced by Tonalide, indicating the role of other obesogenic mechanisms for this compound.
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Affiliation(s)
- Anna Pereira-Fernandes
- Systemic Physiological and Ecotoxicological Research (SPHERE), Department of Biology, University of Antwerp, Antwerp, Belgium
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Cui JJ, Shen H, Tran-Dubé M, Nambu M, McTigue M, Grodsky N, Ryan K, Yamazaki S, Aguirre S, Parker M, Li Q, Zou H, Christensen J. Lessons from (S)-6-(1-(6-(1-methyl-1H-pyrazol-4-yl)-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)ethyl)quinoline (PF-04254644), an inhibitor of receptor tyrosine kinase c-Met with high protein kinase selectivity but broad phosphodiesterase family inhibition leading to myocardial degeneration in rats. J Med Chem 2013; 56:6651-65. [PMID: 23944843 DOI: 10.1021/jm400926x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The hepatocyte growth factor (HGF)/c-Met signaling axis is deregulated in many cancers and plays important roles in tumor invasive growth and metastasis. An exclusively selective c-Met inhibitor (S)-6-(1-(6-(1-methyl-1H-pyrazol-4-yl)-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)ethyl)quinoline (8) was discovered from a highly selective high-throughput screening hit via structure-based drug design and medicinal chemistry lead optimization. Compound 8 had many attractive properties meriting preclinical evaluation. Broad off-target screens identified 8 as a pan-phosphodiesterase (PDE) family inhibitor, which was implicated in a sustained increase in heart rate, increased cardiac output, and decreased contractility indices, as well as myocardial degeneration in in vivo safety evaluations in rats. Compound 8 was terminated as a preclinical candidate because of a narrow therapeutic window in cardio-related safety. The learning from multiparameter lead optimization and strategies to avoid the toxicity attrition at the late stage of drug discovery are discussed.
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Affiliation(s)
- J Jean Cui
- La Jolla Laboratories, Pfizer Worldwide Research and Development , 10770 Science Center Drive, San Diego, California 92121, United States
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Samluk A, Zakrzewska KE, Pluta KD. Generation of fluorescently labeled cell lines, C3A hepatoma cells, and human adult skin fibroblasts to study coculture models. Artif Organs 2013; 37:E123-30. [PMID: 23581829 DOI: 10.1111/aor.12064] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hepatic/nonhepatic cell cocultures are widely used in studies on the role of homo- and heterotypic interactions in liver physiology and pathophysiology. In this article, for the first time, establishment of the coculture model employing hepatoma C3A cells and human skin fibroblasts, stably expressing fluorescent markers, is described. Suitability of the model in studying coculture conditions using fluorescence microscopy and flow cytometry was examined. C3A cells spontaneously formed island-like growth patterns surrounded by fibroblasts. The "islands" size and resulting intensity of the homo- and heterotypic interactions can easily be tuned by applying various plated cells ratios. We examined the capability of the hepatoma cells to produce albumin in hepatic/nonhepatic cell cocultures. The enzyme-linked immunosorbent assay (ELISA) tests showed that greater number of fibroblasts in coculture, resulting in smaller sizes of hepatoma "islands," and thus, a larger heterotypic interface, promoted higher albumin synthesis. The use of fluorescently labeled cells in flow cytometry measurements enabled us to separately gate two cell populations and to evaluate protein expression only in/on cells of interest. Flow cytometry confirmed ELISA results indicating the highest albumin production in hepatoma cells cocultured with the greatest number of fibroblasts and the inhibited protein synthesis in coculture with osteosarcoma cells.
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Affiliation(s)
- Anna Samluk
- Department of Hybrid Microbiosystem Engineering, Nalecz Institute of Biocybernetics and Biomedical Engineering, PAS, Warsaw, Poland
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Lapchak PA. Drug-like property profiling of novel neuroprotective compounds to treat acute ischemic stroke: guidelines to develop pleiotropic molecules. Transl Stroke Res 2013; 4:328-42. [PMID: 23687519 PMCID: PMC3653324 DOI: 10.1007/s12975-012-0200-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The development of novel neuroprotective compounds to treat acute ischemic stroke (AIS) has been problematic and quite complicated, since many candidates that have been tested clinically lacked significant pleiotropic activity, were unable to effectively cross the blood brain barrier (BBB), had poor bioavailability or were toxic. Moreover, the compounds did not confer significant neuroprotection or clinical efficacy measured using standard behavioral endpoints, when studied in clinical trials in a heterogeneous population of stroke patients. To circumvent some of the drug development problems describe above, we have used a rational funnel approach to identify and develop promising candidates. Using a step-wise approach, we have identified a series of compounds based upon two different neuroprotection assays. We have then taken the candidates and determined their "drug-like" properties. This guidelines article details in vitro screening assays used to show pleiotropic activity of a series of novel compounds; including enhanced neuroprotective activity compared to the parent compound fisetin. Moreover, for preliminary drug de-risking or risk reduction during development, we used compound assessment in the CeeTox assay, ADME toxicity using the AMES test for genotoxicity and interaction with Cytochrome P450 using CYP450 inhibition analysis against a spectrum of CYP450 enzymes (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4) as a measure of drug interaction. Moreover, the compounds have been studied using a transfected Madin Darby canine kidney (MDCK) cell assay to assess blood brain barrier penetration (BBB). Using this series of assays, we have identified 4 novel molecules to be developed as an AIS treatment.
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Affiliation(s)
- Paul A Lapchak
- Director of Translational Research, Cedars-Sinai Medical Center, Department of Neurology, Davis Research Building, D-2091, 110 N. George Burns Road, Los Angeles, CA 90048 USA
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Endeshaw M, Zhu X, He S, Pandharkar T, Cason E, Mahasenan KV, Agarwal H, Li C, Munde M, Wilson WD, Bahar M, Doskotch RW, Kinghorn AD, Kaiser M, Brun R, Drew ME, Werbovetz KA. 8,8-dialkyldihydroberberines with potent antiprotozoal activity. JOURNAL OF NATURAL PRODUCTS 2013; 76:311-5. [PMID: 23167812 DOI: 10.1021/np300638f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Semisynthetic 8,8-dialkyldihydroberberines (8,8-DDBs) were found to possess mid- to low-nanomolar potency against Plasmodium falciparum blood-stage parasites, Leishmania donovani intracellular amastigotes, and Trypanosoma brucei brucei bloodstream forms. For example, 8,8-diethyldihydroberberine chloride (5b) exhibited in vitro IC50 values of 77, 100, and 5.3 nM against these three parasites, respectively. In turn, two 8,8-dialkylcanadines, obtained by reduction of the corresponding 8,8-DDBs, were much less potent against these parasites in vitro. While the natural product berberine is a weak DNA binder, the 8,8-DDBs displayed no affinity for DNA, as assessed by changes in the melting temperature of poly(dA·dT) DNA. Selected 8,8-DDBs showed efficacy in mouse models of visceral leishmaniasis and African trypanosomiasis, with 8,8-dimethyldihydroberberine chloride (5a) reducing liver parasitemia by 46% in L. donovani-infected BALB/c mice when given at an intraperitoneal dose of 10 mg/kg/day for five days. The 8,8-DDBs may thus serve as leads for discovering new antimalarial, antileishmanial, and antitrypanosomal drug candidates.
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Affiliation(s)
- Molla Endeshaw
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University , Columbus, Ohio 43210, USA
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Metabolite structure analysis by high-resolution MS: supporting drug-development studies. Bioanalysis 2013; 5:463-79. [DOI: 10.4155/bio.13.3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Effective characterization of drug metabolites in complex biological matrices is facilitated by mass spectrometers with high resolving power, mass accuracy and sensitivity. This review begins with an overview of high-resolution MS terminology and the different types of instrumentation that are currently available. Metabolite structure analysis offers unique challenges and, therefore, the different types of approaches used to solve problems are highlighted through specific examples. Overall, this review describes the value that high-resolution MS brings to drug-metabolism studies.
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129
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Long-term three-dimensional cell culture and anticancer drug activity evaluation in a microfluidic chip. Biosens Bioelectron 2013; 40:68-74. [DOI: 10.1016/j.bios.2012.06.017] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 06/11/2012] [Accepted: 06/12/2012] [Indexed: 12/21/2022]
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130
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Lapchak PA, Bombien R, Rajput PS. J-147 a Novel Hydrazide Lead Compound to Treat Neurodegeneration: CeeTox ™ Safety and Genotoxicity Analysis. ACTA ACUST UNITED AC 2013; 4. [PMID: 25364619 PMCID: PMC4215638 DOI: 10.4172/2155-9562.1000158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
J-147 is a broad spectrum neuroprotective phenyl hydrazide compound with significant neurotrophic properties related to the induction of brain-derived neurotrophic factor (BDNF). Because this molecule is pleiotropic, it may have substantial utility in the treatment of a wide range of neurodegenerative diseases including acute ischemic stroke (AIS), traumatic brain injury(TBI), and Alzheimer’s disease(AD) where both neuroprotection and neurotrophism would be beneficial. Because of the pleiotropic actions of J-147, we sought to determine the safety profile of the drug using multiple assay analysis. For CeeTox analyses, we used a rat hepatoma cell line (H4IIE) resulted in estimated CTox value (i.e.: sustained concentration expected to produce toxicity in a 14 day repeat dosing study) of 90 μM for J-147. The CeeTox panel shows that J-147 produced some adverse effects on cellular activities, in particular mitochondrial function, but only with high concentrations of the drug. J-147 was also not genetoxic with or without Aroclor-1254 treatment. For J-147, based upon extensive neuroprotection assay data previously published, and the CeeTox assay (CTox value of 90 μM) in this study, we estimated in vitro neuroprotection efficacy (EC50 range 0.06–0.115 μM)/toxicity ratio is 782.6–1500 fold and the neurotrophism (EC50 range 0.025 μM)/toxicity ratio is 3600, suggesting that there is a significant therapeutic safety window for J-147 and that it should be further developed as a novel neuroprotective-neurotrophic agent to treat neurodegenerative disease taking into account current National Institute of Neurological Disorders and Stroke (NINDS) RIGOR guidelines.
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Affiliation(s)
- Paul A Lapchak
- Department of Neurology and Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, USA
| | - Rene Bombien
- Division of Cardiothoracic Surgery, Cedars-Sinai Medical Center, Los Angeles, USA
| | - Padmesh S Rajput
- Department of Neurology, Advanced Health Sciences Pavilion, Los Angeles, USA
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131
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Mining the Potential of Label-Free Biosensors for Seven-Transmembrane Receptor Drug Discovery. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 115:123-42. [DOI: 10.1016/b978-0-12-394587-7.00003-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Bancos S, Tsai DH, Hackley V, Weaver JL, Tyner KM. Evaluation of Viability and Proliferation Profiles on Macrophages Treated with Silica Nanoparticles In Vitro via Plate-Based, Flow Cytometry, and Coulter Counter Assays. ACTA ACUST UNITED AC 2012. [DOI: 10.5402/2012/454072] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Nanoparticles (NPs) are known to interfere with many high-throughput cell viability and cell proliferation assays, which complicates the assessment of their potential toxic effects. The aim of this study was to compare viability and proliferation results for colloidal silica (SiO2 NP; 7 nm) in the RAW 264.7 mouse macrophage cell line using three different techniques: plate-based assays, flow cytometry analysis, and Coulter counter assays. Our data indicate that CellTiter-Blue, XTT, and CyQuant plate-based assays show increased values over control at low SiO2 NPs concentrations (0.001–0.01 g/L). SiO2 NPs show little-to-no interference with flow cytometry and Coulter counter assays, which not only were more reliable in determining cell viability and proliferation at low concentrations in vitro, but also identified changes in cell granularity and size that were not captured by the plate-based assays. At high SiO2 NP concentrations (1 g/L) all techniques indicated cytotoxicity. In conclusion, flow cytometry and Coulter counter identified new cellular features, and flow cytometry offered more flexibility in analyzing the viability and proliferation profile of SiO2 NP-treated RAW 264.7 cells.
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Affiliation(s)
- S. Bancos
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Building 64, Room 2086 HFD-910, 10903 New Hampshire Avenue, Silver Spring, MD 20993, USA
| | - D.-H. Tsai
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 8520, Gaithersburg, MD 20899-850, USA
| | - V. Hackley
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Mail Stop 8520, Gaithersburg, MD 20899-850, USA
| | - J. L. Weaver
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Building 64, Room 2086 HFD-910, 10903 New Hampshire Avenue, Silver Spring, MD 20993, USA
| | - K. M. Tyner
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Building 64, Room 2086 HFD-910, 10903 New Hampshire Avenue, Silver Spring, MD 20993, USA
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133
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Tarleton M, Gilbert J, Sakoff JA, McCluskey A. Cytotoxic 2-phenyacrylnitriles, the importance of the cyanide moiety and discovery of potent broad spectrum cytotoxic agents. Eur J Med Chem 2012; 57:65-73. [PMID: 23047225 DOI: 10.1016/j.ejmech.2012.09.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 09/08/2012] [Accepted: 09/11/2012] [Indexed: 01/09/2023]
Abstract
We previously reported the discovery of a simple conjugated cyano pharmacophore which had led to the development of (Z)-2-(3,4-dichlorophenyl)-3-(4-nitrophenyl)acrylonitrile, as a selective inhibitor of oestrogen receptor positive (ER+ve) human breast cancer cell line, MCF-7. Further exploration though modification of the acrylonitrile and aromatic substituents has highlighted key structural components necessary for broad spectrum cytotoxicity. The acrylic acid derivates (Z)-2-(3,4-dichlorophenyl)-3-(4-nitrophenyl)acrylic acid and (Z)-2-(3,4-dichlorophenyl)-3-(4-methoxyphenyl)acrylic acid (9) were inactive; confirming the importance of the cyanide moiety. The most potent 2-phenylacrylonitriles synthesized were (Z)-2-(3,4-dichlorophenyl)-3-(1H-indol-3-yl)acrylonitrile and (Z)-2-(3,4-dichlorophenyl)-3-(1H-indol-5-yl)acrylonitrile (20) with an average GI(50) values of 1.4 and 0.53 μM respectively. Five additional (Z)-2-(3,4-dichlorophenyl)-3-(indolyl)acrylonitriles also displayed average GI(50) values of ≤8.4 μM. In the case of indole, this represents a 32-fold increase in broad spectrum cytotoxicity relative to the lead.
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Affiliation(s)
- Mark Tarleton
- Chemistry, School of Environmental & Life Science, The University of Newcastle, University Drive Callaghan, NSW 2308, Australia
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134
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Rampersad SN. Multiple applications of Alamar Blue as an indicator of metabolic function and cellular health in cell viability bioassays. SENSORS (BASEL, SWITZERLAND) 2012; 12:12347-60. [PMID: 23112716 PMCID: PMC3478843 DOI: 10.3390/s120912347] [Citation(s) in RCA: 604] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 08/21/2012] [Accepted: 08/31/2012] [Indexed: 02/07/2023]
Abstract
Accurate prediction of the adverse effects of test compounds on living systems, detection of toxic thresholds, and expansion of experimental data sets to include multiple toxicity end-point analysis are required for any robust screening regime. Alamar Blue is an important redox indicator that is used to evaluate metabolic function and cellular health. The Alamar Blue bioassay has been utilized over the past 50 years to assess cell viability and cytotoxicity in a range of biological and environmental systems and in a number of cell types including bacteria, yeast, fungi, protozoa and cultured mammalian and piscine cells. It offers several advantages over other metabolic indicators and other cytotoxicity assays. However, as with any bioassay, suitability must be determined for each application and cell model. This review seeks to highlight many of the important considerations involved in assay use and design in addition to the potential pitfalls.
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Affiliation(s)
- Sephra N Rampersad
- Department of Life Sciences, The University of the West Indies, West Indies, St Augustine, Trinidad and Tobago.
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135
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Vinken M, Vanhaecke T, Rogiers V. Primary hepatocyte cultures as in vitro tools for toxicity testing: quo vadis? Toxicol In Vitro 2012; 26:541-4. [PMID: 22261203 DOI: 10.1016/j.tiv.2012.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 12/20/2011] [Accepted: 01/04/2012] [Indexed: 12/29/2022]
Abstract
Cultures of primary hepatocytes are versatile tools that can serve many in vitro toxicity testing purposes. However, they cope with dedifferentiation, a process that is already initiated during the hepatocyte isolation procedure and that is manifested as the progressive loss of functionality upon subsequent cultivation. A number of strategies to prevent dedifferentiation have been introduced over the last decades, all which aim at re-establishing the in vivo hepatocyte micro-environment in vitro, but that are of merely limited success. Recent mechanistic insight into the mechanisms that underlie hepatocyte dedifferentiation has opened new avenues for the development of novel approaches that target the actual causes of this deteriorative process and thus for the generation of a long-term hepatic in vitro tool. Such experimental system is urgently needed, especially in the light of the stringent European legislative modifications that are currently encountered by the pharmaceutical, chemical and, particularly, the cosmetic industry.
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Affiliation(s)
- Mathieu Vinken
- Department of Toxicology, Center for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium.
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136
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Wallace AD. Toxic Endpoints in the Study of Human Exposure to Environmental Chemicals. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 112:89-115. [DOI: 10.1016/b978-0-12-415813-9.00004-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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137
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Lapchak PA. CeeTox Analysis to De-risk Drug Development: The Three Antioxidants (NXY-059, Radicut, and STAZN). Transl Stroke Res 2012. [DOI: 10.1007/978-1-4419-9530-8_31] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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138
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Lin Z, Will Y. Evaluation of Drugs With Specific Organ Toxicities in Organ-Specific Cell Lines. Toxicol Sci 2011; 126:114-27. [DOI: 10.1093/toxsci/kfr339] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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139
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Smart DJ, Ahmedi KP, Harvey JS, Lynch AM. Genotoxicity screening via the γH2AX by flow assay. Mutat Res 2011; 715:25-31. [PMID: 21824484 DOI: 10.1016/j.mrfmmm.2011.07.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 06/10/2011] [Accepted: 07/08/2011] [Indexed: 05/31/2023]
Abstract
The measurement of serine139-phosphorylated histone H2AX (γH2AX) provides a biomarker of DNA double-strand breaks (DSBs) and may identify potential genotoxic activity. In order to evaluate a flow cytometry assay for γH2AX detection (hereafter termed the γH2AX by flow assay), 6 prototypical (3 pro- and 3 proximate) genotoxins, i.e. dimethylbenz[a]anthracene (DMBA), 2-acetylaminofluorene (2-AAF), benzo[a]pyrene (B[a]P), methyl methane sulphonate (MMS), methyl nitrosourea (MNU) and 4-nitroquinoline oxide (4NQO), were selected to define assay evaluation criteria. In addition, 3 non-genotoxic cytotoxins (phthalic anhydride, n-butyl chloride and hexachloroethane) were included to investigate the influence of cytotoxicity on assay performance. At similar cytotoxicity levels (relative cell counts; RCC 75-40%) all prototypical genotoxins induced marked concentration-dependent increases in γH2AX compared with the non-genotoxins. As a result, assay evaluation criteria for a positive effect were defined as >1.5-fold γH2AX @ RCC >25%. Twenty five additional chemicals with diverse structures and genotoxic activity were selected to evaluate the γH2AX by flow assay. Results were compared with Ames bacterial and in vitro mammalian genotoxicity tests (mouse lymphoma assay and/or chromosome aberration assay). γH2AX by flow assay results were highly predictive of Ames (sensitivity 100%; specificity 67%; concordance 82%) and in vitro mammalian genotoxicity tests (sensitivity 91%; specificity 89%; concordance 91%) and provide additional evidence that γH2AX is a biomarker of potential genotoxic activity, underpinned mechanistically by the cellular response to DSBs. Discordant findings were predominately attributed to differences in specificity for some mammalian cell genotoxins that are Ames non-mutagens or for "biologically-irrelevant" positives in the mammalian tests. Simple anilines were classified as genotoxic following rat liver S9-mediated bioactivation, however, effects on γH2AX were atypical and limited to a small sub-population of S-phase nuclei. Nevertheless, the γH2AX by flow assay represents a novel genotoxicity assay with the potential to flag both pro- and proximate genotoxins.
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Affiliation(s)
- D J Smart
- Safety Assessment, GlaxoSmithKline R&D, Park Road, Ware, Hertfordshire SG12 0DP, UK.
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