Applied In Vitro Toxicology最新文献

{"title":"Avoiding False Positives and Optimizing Identification of True Negatives in Estrogen Receptor Binding and Agonist/Antagonist Assays.","authors":"Michael W Hornung,&nbsp;Mark A Tapper,&nbsp;Jeffrey S Denny,&nbsp;Barbara R Sheedy,&nbsp;Raymond Erickson,&nbsp;Taylor J Sulerud,&nbsp;Richard C Kolanczyk,&nbsp;Patricia K Schmieder","doi":"10.1089/aivt.2016.0021","DOIUrl":"https://doi.org/10.1089/aivt.2016.0021","url":null,"abstract":"<p><p>The potential for chemicals to affect endocrine signaling is commonly evaluated via <i>in vitro</i> receptor binding and gene activation, but these assays, especially antagonism assays, have potential artifacts that must be addressed for accurate interpretation. Results are presented from screening 94 chemicals from 54 chemical groups for estrogen receptor (ER) activation in a competitive rainbow trout ER (rtER) binding assay and a trout liver slice vitellogenin mRNA expression assay. Results from true competitive agonists and antagonists, and inactive chemicals with little or no indication of ER binding or gene activation were easily interpreted. However, results for numerous industrial chemicals were more challenging to interpret, including chemicals with: (1) apparent competitive binding curves but no gene activation, (2) apparent binding and gene inhibition with evidence of either cytotoxicity or changes in assay media pH, (3) apparent binding but non-competitive gene inhibition of unknown cause, or (4) no rtER binding and gene inhibition not due to competitive ER interaction but due to toxicity, pH change, or some unknown cause. The use of endpoints such as toxicity, pH, precipitate formation, and determination of inhibitor dissociation constants (Ki) for interpreting the results of antagonism and binding assays for diverse chemicals is presented. Of the 94 chemicals tested for antagonism only two, tamoxifen and ICI-182780, were found to be true competitive antagonists. This report highlights the use of two different concentrations of estradiol tested in combination with graded concentrations of test chemical to provide the confirmatory evidence to distinguish true competitive antagonism from apparent antagonism.</p>","PeriodicalId":37448,"journal":{"name":"Applied In Vitro Toxicology","volume":"3 2","pages":"163-181"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1089/aivt.2016.0021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36430370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tobacco Smoke Constituents Trigger Cytoplasmic Calcium Release.","authors":"M Flori Sassano,&nbsp;Arunava Ghosh,&nbsp;Robert Tarran","doi":"10.1089/aivt.2016.0039","DOIUrl":"https://doi.org/10.1089/aivt.2016.0039","url":null,"abstract":"<p><p>Cytosolic Ca²⁺ is a universal second messenger that is involved in many processes throughout the body, including the regulation of cell growth/cell division, apoptosis, and the secretion of both ions, and macromolecules. Tobacco smoke exerts multiple effects on airway epithelia and we have previously shown that Kentucky reference cigarette smoke exposure elevated the second messenger Ca²⁺, leading to dysfunctional ion secretion. In this study, we tested whether little cigar and commercial cigarette smoke exposure exerts similar effects on intracellular Ca²⁺ levels. Indeed, Swisher Sweets, Captain Black, and Cheyenne little cigars, as well as Camel, Marlboro, and Newport cigarettes, triggered a comparable increase in intracellular Ca²⁺ as seen with Kentucky reference cigarettes in human bronchial epithelia. We also found that Kentucky reference cigarette smoke exposure caused increases in Ca²⁺ in HEK293T cells and that similar increases in Ca²⁺ were seen with the tobacco smoke metabolites 1-NH₂-naphthalene, formaldehyde, nicotine, and nicotine-derived nitrosamine ketone. Given the large number of physiological processes governed by changes in cytosolic Ca²⁺, our data suggest that Ca²⁺ signaling is a useful and reproducible assay that can be used to probe the propensity of tobacco products and their constituents to cause toxicity.</p>","PeriodicalId":37448,"journal":{"name":"Applied In Vitro Toxicology","volume":"3 2","pages":"193-198"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1089/aivt.2016.0039","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35092907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inflammatory Response and Barrier Dysfunction by Different e-Cigarette Flavoring Chemicals Identified by Gas Chromatography-Mass Spectrometry in e-Liquids and e-Vapors on Human Lung Epithelial Cells and Fibroblasts.","authors":"Janice Gerloff,&nbsp;Isaac K Sundar,&nbsp;Robert Freter,&nbsp;Emily R Sekera,&nbsp;Alan E Friedman,&nbsp;Risa Robinson,&nbsp;Todd Pagano,&nbsp;Irfan Rahman","doi":"10.1089/aivt.2016.0030","DOIUrl":"https://doi.org/10.1089/aivt.2016.0030","url":null,"abstract":"<p><p>Recent studies suggest that electronic cigarette (e-cig) flavors can be harmful to lung tissue by imposing oxidative stress and inflammatory responses. The potential inflammatory response by lung epithelial cells and fibroblasts exposed to e-cig flavoring chemicals in addition to other risk-anticipated flavor enhancers inhaled by e-cig users is not known. The goal of this study was to evaluate the release of the proinflammatory cytokine (interleukin-8 [IL-8]) and epithelial barrier function in response to different e-cig flavoring chemicals identified in various e-cig e-liquid flavorings and vapors by chemical characterization using gas chromatography-mass spectrometry analysis. Flavorings, such as acetoin (butter), diacetyl, pentanedione, maltol (malt), ortho-vanillin (vanilla), coumarin, and cinnamaldehyde in comparison with tumor necrosis factor alpha (TNFα), were used in this study. Human bronchial epithelial cells (Beas2B), human mucoepidermoid carcinoma epithelial cells (H292), and human lung fibroblasts (HFL-1) were treated with each flavoring chemical for 24 hours. The cells and conditioned media were then collected and analyzed for toxicity (viability %), lung epithelial barrier function, and proinflammatory cytokine IL-8 release. Cell viability was not significantly affected by any of the flavoring chemicals tested at a concentration of 10 μM to 1 mM. Acetoin and diacetyl treatment induced IL-8 release in Beas2B cells. Acetoin- and pentanedione-treated HFL-1 cells produced a differential, but significant response for IL-8 release compared to controls and TNFα. Flavorings, such as ortho-vanillin and maltol, induced IL-8 release in Beas2B cells, but not in H292 cells. Of all the flavoring chemicals tested, acetoin and maltol were more potent inducers of IL-8 release than TNFα in Beas2B and HFL-1 cells. Flavoring chemicals rapidly impaired epithelial barrier function in human bronchial epithelial cells (16-HBE) as measured by electric cell surface impedance sensing. Our findings suggest that some of the e-cig liquids/aerosols containing flavoring chemicals can cause significant loss of epithelial barrier function and proinflammatory response in lung cells.</p>","PeriodicalId":37448,"journal":{"name":"Applied In Vitro Toxicology","volume":"3 1","pages":"28-40"},"PeriodicalIF":0.0,"publicationDate":"2017-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1089/aivt.2016.0030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"34852058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>In Vitro</i> and <i>Ex Vivo</i> Approaches to Evaluate Next-Generation Tobacco and Non-Tobacco Products on Human Blood Platelets.","authors":"Sherry L Spinelli,&nbsp;Katie L Lannan,&nbsp;Shannon G Loelius,&nbsp;Richard P Phipps","doi":"10.1089/aivt.2016.0034","DOIUrl":"https://doi.org/10.1089/aivt.2016.0034","url":null,"abstract":"Abstract Human blood platelets are major hemostatic regulators in the circulation and important in the mediation of chronic inflammation and immunomodulation. They are key elements that promote cardiovascular pathogenesis that leads to atherosclerosis, thrombosis, myocardial infarction, and stroke. New information on tobacco use and platelet dysregulation shows that these highly understudied vascular cells are dysregulated by tobacco smoke. Thus, platelet function studies should be an important consideration for the evaluation of existing and next-generation tobacco and non-tobacco products. Novel in vitro approaches are being sought to investigate these products and their influence on platelet function. Platelets are ideally suited for product assessment, as robust and novel in vitro translational methods are available to assess platelet function. Furthermore, the use of human biological systems has the advantage that risk predictions will better reflect the human condition.","PeriodicalId":37448,"journal":{"name":"Applied In Vitro Toxicology","volume":"3 1","pages":"110-120"},"PeriodicalIF":0.0,"publicationDate":"2017-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1089/aivt.2016.0034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"34852060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Bench-Top <i>In Vitro</i> Wound Assay to Demonstrate the Effects of Platelet-Rich Plasma and Depleted Uranium on Dermal Fibroblast Migration.","authors":"Bronson I Pinto,&nbsp;Aaron J Tabor,&nbsp;Diane M Stearns,&nbsp;Robert B Diller,&nbsp;Robert S Kellar","doi":"10.1089/aivt.2016.0001","DOIUrl":"https://doi.org/10.1089/aivt.2016.0001","url":null,"abstract":"<p><p>Cellular migration assays are useful tools to investigate physiologic events on the bench top. Furthermore, this migration assay can be utilized to investigate wound healing therapeutics (those that encourage or accelerate wound closure) as well as deleterious agents (ones that mitigate or slow wound closure). The current study used an <i>in vitro</i> scratch assay to measure the effects of platelet-rich plasma (PRP) and depleted uranium (DU) in the form of uranyl acetate on cellular migration of human neonatal dermal fibroblasts in an <i>in vitro</i> simulation of wound healing. Data analyses included percent wound closure measured as the distance between cell margins, and rates of wound closure versus untreated controls. The highest doses of PRP (0.063, 0.125%) resulted in 50-65% wound closure after 4-8 hours relative to 38-44% in controls and the low-dose treatment group (0.031%). The high-dose treatments of PRP (0.125, 0.063%) reached 100% wound closure at 12 hours postwound versus 16 hours for controls and the low-dose treatment group (0.031%). Conversely, the higher doses of DU treatments (50 and 100 μM) resulted in <80% closure versus 100% closure in controls after 16 hours, with full closure observed at 20 hours. The highest dose of DU (1,000 μM) resulted in <20% closure versus 100% closure in controls after 16 hours. The use of the described scratch assay serves as a translatable bench-top model that has the potential to predict <i>in vivo</i> outcomes, and in many early studies can help to demonstrate proof-of-concept before moving into complex biological systems.</p>","PeriodicalId":37448,"journal":{"name":"Applied In Vitro Toxicology","volume":"2 3","pages":"151-156"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1089/aivt.2016.0001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35465969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Microphysiology Systems Database for Analyzing and Modeling Compound Interactions with Human and Animal Organ Models.","authors":"Albert Gough,&nbsp;Lawrence Vernetti,&nbsp;Luke Bergenthal,&nbsp;Tong Ying Shun,&nbsp;D Lansing Taylor","doi":"10.1089/aivt.2016.0011","DOIUrl":"https://doi.org/10.1089/aivt.2016.0011","url":null,"abstract":"<p><p>Microfluidic human organ models, microphysiology systems (MPS), are currently being developed as predictive models of drug safety and efficacy in humans. To design and validate MPS as predictive of human safety liabilities requires safety data for a reference set of compounds, combined with <i>in vitro</i> data from the human organ models. To address this need, we have developed an internet database, the MPS database (MPS-Db), as a powerful platform for experimental design, data management, and analysis, and to combine experimental data with reference data, to enable computational modeling. The present study demonstrates the capability of the MPS-Db in early safety testing using a human liver MPS to relate the effects of tolcapone and entacapone in the <i>in vitro</i> model to human <i>in vivo</i> effects. These two compounds were chosen to be evaluated as a representative pair of marketed drugs because they are structurally similar, have the same target, and were found safe or had an acceptable risk in preclinical and clinical trials, yet tolcapone induced unacceptable levels of hepatotoxicity while entacapone was found to be safe. Results demonstrate the utility of the MPS-Db as an essential resource for relating <i>in vitro</i> organ model data to the multiple biochemical, preclinical, and clinical data sources on <i>in vivo</i> drug effects.</p>","PeriodicalId":37448,"journal":{"name":"Applied In Vitro Toxicology","volume":"2 2","pages":"103-117"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1089/aivt.2016.0011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35296393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cardiovascular Organ-on-a-Chip Platforms for Drug Discovery and Development.","authors":"João Ribas, Hossein Sadeghi, Amir Manbachi, Jeroen Leijten, Katelyn Brinegar, Yu Shrike Zhang, Lino Ferreira, Ali Khademhosseini","doi":"10.1089/aivt.2016.0002","DOIUrl":"10.1089/aivt.2016.0002","url":null,"abstract":"<p><p>Cardiovascular diseases are prevalent worldwide and are the most frequent causes of death in the United States. Although spending in drug discovery/development has increased, the amount of drug approvals has seen a progressive decline. Particularly, adverse side effects to the heart and general vasculature have become common causes for preclinical project closures, and preclinical models do not fully recapitulate human <i>in vivo</i> dynamics. Recently, organs-on-a-chip technologies have been proposed to mimic the dynamic conditions of the cardiovascular system-in particular, heart and general vasculature. These systems pay particular attention to mimicking structural organization, shear stress, transmural pressure, mechanical stretching, and electrical stimulation. Heart- and vasculature-on-a-chip platforms have been successfully generated to study a variety of physiological phenomena, model diseases, and probe the effects of drugs. Here, we review and discuss recent breakthroughs in the development of cardiovascular organs-on-a-chip platforms, and their current and future applications in the area of drug discovery and development.</p>","PeriodicalId":37448,"journal":{"name":"Applied In Vitro Toxicology","volume":"2 2","pages":"82-96"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5044977/pdf/aivt.2016.0002.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35467425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}