1
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Nachtnebel M, Führer B, Ettenberger-Bornberg G, Mertl J, Kaufmann L, Schroettner H, Rattenberger J. Determination of ragweed allergen Amb a 1 distribution in aerosols using ELISA and immunogold scanning electron microscopy. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY. GLOBAL 2022; 1:265-272. [PMID: 37779543 PMCID: PMC10509994 DOI: 10.1016/j.jacig.2022.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/19/2022] [Accepted: 05/30/2022] [Indexed: 10/03/2023]
Abstract
Background Ragweed as an invasive species in Europe has become more important for allergy sufferers in the last decade. Because pollen fractions can be found in the respirable fraction of aerosols, they can generate severe disease progressions. Objective To obtain information about the concentration and distribution of 1 of the main ragweed allergens Ambrosia artemisiifolia 1 in the air of Vienna, PM10 and PM2.5 fine dust filters were analyzed. Methods Standard fine dust filters used for air quality monitoring were analyzed via ELISA and immunogold scanning electron microscopy. Results Via ELISA it was possible to show that already at pollen season start in August a recognizably high A artemisiifolia 1 concentration can be found. In addition, the allergen concentration in the air stays comparatively high after the peak season has ended even when the pollen concentration drops to a moderate level. The immunogold electron microscopy investigation directly applied on filters shows that the allergen can be found on organic as well as on mixtures of organic and inorganic particles. A first semistatistical analysis of the labeled particle sizes indicates that a large number of the allergen carriers can be found within the smallest particle size range. Nevertheless, further investigations are needed to obtain enough particle counts for a significant statistical analysis. Conclusions It was possible to show that reliable results can be obtained from ELISA and immunogold scanning electron microscopy directly applied on filters that are used in air quality monitoring sites. By adaptation of the used protocols, it should be possible to obtain respective information about further allergens.
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Affiliation(s)
| | - Bernadette Führer
- Österreichisches Forschungsinstitut für Chemie und Technik (OFI), Franz-Grill-Straße 5/Objekt 213, Wien, Austria
| | | | - Johannes Mertl
- Österreichisches Forschungsinstitut für Chemie und Technik (OFI), Franz-Grill-Straße 5/Objekt 213, Wien, Austria
| | - Lilian Kaufmann
- Österreichisches Forschungsinstitut für Chemie und Technik (OFI), Franz-Grill-Straße 5/Objekt 213, Wien, Austria
| | - Hartmuth Schroettner
- Graz Centre for Electron Microscopy (ZFE), Steyrergasse, Graz, Austria
- Institute of Electron Microscopy and Nanoanalysis (FELMI), NAWI Graz, Graz University of Technology, Steyrergasse 17, Graz, Austria
| | - Johannes Rattenberger
- Graz Centre for Electron Microscopy (ZFE), Steyrergasse, Graz, Austria
- Institute of Electron Microscopy and Nanoanalysis (FELMI), NAWI Graz, Graz University of Technology, Steyrergasse 17, Graz, Austria
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2
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Li Y, Zhu Y, Zhao B, Yao Q, Xu H, Lv S, Wang J, Sun Z, Li Y, Guo C. Amorphous silica nanoparticles caused lung injury through the induction of epithelial apoptosis via ROS/Ca 2+/DRP1-mediated mitochondrial fission signaling. Nanotoxicology 2022; 16:713-732. [PMID: 36441139 DOI: 10.1080/17435390.2022.2144774] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 11/03/2022] [Indexed: 11/30/2022]
Abstract
The adverse effects of amorphous silica nanoparticles (SiNPs) exposure on the respiratory system were increasingly recognized, however, its potential pathogenesis still remains not fully elucidated. So, this study aimed to explore its effects on pulmonary injury, and to investigate related mechanisms. Histological investigations illustrated SiNPs triggered the lung injury, mainly manifested as alveolar structure destruction, collagen deposition, and mitochondrial ultrastructural injury. In particular, SiNPs greatly enhanced pulmonary ROS and TUNEL positive rate in lungs, both of which were positively correlated with lung impairments. Further, the underlying mechanisms were investigated in cultured human bronchial epithelial cells (16HBE). Consistent with the in vivo findings, SiNPs caused the impairments on mitochondrial structure, as well as the activation of ROS generation and oxidative injury. Upon SiNPs stimuli, mitochondrial respiration was greatly inhibited, while Ca2+ overload in cytosol and mitochondria owing to ER calcium release was noticed, resulting in mitochondrial-dependent epithelial apoptosis. More importantly, mitochondrial dynamics was imbalanced toward a fission type, as evidenced by upregulated DRP1 and its phosphorylation at Ser616 (DRP1s616), while downregulated DRP1s637, and also MFN1, MFN2. Mechanistic investigations revealed that the activation of ROS/Ca2+ signaling promoted DRP1-mediated mitochondrial fission by SiNPs, forming a vicious cycle, and ultimately contributing to apoptosis in 16HBE. In summary, our results disclosed SiNPs caused pulmonary injury through the induction of epithelial apoptosis via a ROS/Ca2+/DRP1-mediated mitochondrial fission axis.
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Affiliation(s)
- Yan Li
- Department of Occupational Health and Environmental Health, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
| | - Yawen Zhu
- Department of Occupational Health and Environmental Health, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
| | - Bosen Zhao
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing, China
| | - Qing Yao
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing, China
| | - Hailin Xu
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing, China
| | - Songqing Lv
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing, China
| | - Ji Wang
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing, China
| | - Zhiwei Sun
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing, China
| | - Yanbo Li
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
- Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing, China
| | - Caixia Guo
- Department of Occupational Health and Environmental Health, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
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3
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Khan K, Ahmad W, Amin MN, Nazar S. Nano-Silica-Modified Concrete: A Bibliographic Analysis and Comprehensive Review of Material Properties. NANOMATERIALS 2022; 12:nano12121989. [PMID: 35745327 PMCID: PMC9228660 DOI: 10.3390/nano12121989] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/27/2022] [Accepted: 06/06/2022] [Indexed: 02/05/2023]
Abstract
Several review studies have been performed on nano-silica-modified concrete, but this study adopted a new method based on scientometric analysis for the keywords’ assessment in the current research area. A scientometric analysis can deal with vast bibliometric data using a software tool to evaluate the diverse features of the literature. Typical review studies are limited in their ability to comprehensively and accurately link divergent areas of the literature. Based on the analysis of keywords, this study highlighted and described the most significant segments in the research of nano-silica-modified concrete. The challenges associated with using nano-silica were identified, and future research is directed. Moreover, prediction models were developed using data from the literature for the strength estimation of nano-silica-modified concrete. It was noted that the application of nano-silica in cement-based composites is beneficial when used up to an optimal dosage of 2–3% due to high pozzolanic reactivity and a filler effect, whereas a higher dosage of nano-silica has a detrimental influence due to the increased porosity and microcracking caused by the agglomeration of nano-silica particles. The mechanical strength might enhance by 20–25% when NS is incorporated in the optimal amount. The prediction models developed for predicting the strength of nano-silica-modified concrete exhibited good agreement with experimental data due to lower error values. This type of analysis may be used to estimate the essential properties of a material, therefore saving time and money on experimental tests. It is recommended to investigate cost-effective methods for the dispersion of nano-silica in higher concentrations in cement mixes; further in-depth studies are required to develop more accurate prediction models to predict nano-silica-modified concrete properties.
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Affiliation(s)
- Kaffayatullah Khan
- Department of Civil and Environmental Engineering, College of Engineering, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
- Correspondence:
| | - Waqas Ahmad
- Department of Civil Engineering, COMSATS University Islamabad, Abbottabad 22060, Pakistan; (W.A.); (S.N.)
| | - Muhammad Nasir Amin
- Department of Civil and Environmental Engineering, College of Engineering, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Sohaib Nazar
- Department of Civil Engineering, COMSATS University Islamabad, Abbottabad 22060, Pakistan; (W.A.); (S.N.)
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4
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Racovita AD. Titanium Dioxide: Structure, Impact, and Toxicity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19095681. [PMID: 35565075 PMCID: PMC9104107 DOI: 10.3390/ijerph19095681] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/02/2022] [Accepted: 05/03/2022] [Indexed: 12/27/2022]
Abstract
Titanium dioxide, first manufactured a century ago, is significant in industry due to its chemical inertness, low cost, and availability. The white mineral has a wide range of applications in photocatalysis, in the pharmaceutical industry, and in food processing sectors. Its practical uses stem from its dual feature to act as both a semiconductor and light scatterer. Optical performance is therefore of relevance in understanding how titanium dioxide impacts these industries. Recent breakthroughs are summarised herein, focusing on whether restructuring the surface properties of titanium dioxide either enhances or inhibits its reactivity, depending on the required application. Its recent exposure as a potential carcinogen to humans has been linked to controversies around titanium dioxide's toxicity; this is discussed by illustrating discrepancies between experimental protocols of toxicity assays and their results. In all, it is important to review the latest achievements in fast-growing industries where titanium dioxide prevails, while keeping in mind insights into its disputed toxicity.
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Affiliation(s)
- Anca Diana Racovita
- Department of Chemistry, Faculty of Science, University of Warwick, Coventry CV4 7AL, UK
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5
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Guo C, Liu Y, Li Y. Adverse effects of amorphous silica nanoparticles: Focus on human cardiovascular health. JOURNAL OF HAZARDOUS MATERIALS 2021; 406:124626. [PMID: 33296760 DOI: 10.1016/j.jhazmat.2020.124626] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 11/04/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
Amorphous silica nanoparticle (SiNPs) has tremendous potential for a host of applications, while its mass production, broad application and environmental release inevitably increase the risk of human exposure. SiNPs could enter into the human body through different routes such as inhalation, ingestion, skin contact and even injection for medical applications. The cardiovascular system is gradually recognized as one of the primary sites for engineered NPs exerting adverse effects. Accumulating epidemiological or experimental evidence support the association between SiNPs exposure and adverse cardiovascular effects. However, this topic is still in its infancy, and the literature shows high inter-study variability and even contradictory results. New challenges still present in the safety evaluation of SiNPs, and its toxicological mechanisms are poorly understood. Here, scientific papers related to cardiovascular studies of SiNPs in vivo and in vitro were selected, and the updated particle-caused cardiovascular toxicity and potential mechanisms were summarized. Moreover, the understanding of how factors primarily including exposure dose, route of administration, particle size and surface properties, influence the interaction between SiNPs and cardiovascular system was discussed. In particular, the adverse outcome pathway (AOP) framework by which SiNPs cause deleterious effects in the cardiovascular system was described, aiming to provide useful information necessary for the regulatory decision and to guide a safer application of nanotechnology.
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Affiliation(s)
- Caixia Guo
- Department of Occupational Health and Environmental Health, School of Public Health, Capital Medical University, Beijing 100069, China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China
| | - Yufan Liu
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Yanbo Li
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing 100069, China; Department of Toxicology and Sanitary Chemistry, School of Public Health, Capital Medical University, Beijing 100069, China.
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6
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Wang L, Wu WM, Bolan NS, Tsang DCW, Li Y, Qin M, Hou D. Environmental fate, toxicity and risk management strategies of nanoplastics in the environment: Current status and future perspectives. JOURNAL OF HAZARDOUS MATERIALS 2021; 401:123415. [PMID: 32763705 PMCID: PMC7345412 DOI: 10.1016/j.jhazmat.2020.123415] [Citation(s) in RCA: 248] [Impact Index Per Article: 82.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/23/2020] [Accepted: 07/04/2020] [Indexed: 05/19/2023]
Abstract
Tiny plastic particles considered as emerging contaminants have attracted considerable interest in the last few years. Mechanical abrasion, photochemical oxidation and biological degradation of larger plastic debris result in the formation of microplastics (MPs, 1 μm to 5 mm) and nanoplastics (NPs, 1 nm to 1000 nm). Compared with MPs, the environmental fate, ecosystem toxicity and potential risks associated with NPs have so far been less explored. This review provides a state-of-the-art overview of current research on NPs with focus on currently less-investigated fields, such as the environmental fate in agroecosystems, migration in porous media, weathering, and toxic effects on plants. The co-transport of NPs with organic contaminants and heavy metals threaten human health and ecosystems. Furthermore, NPs may serve as a novel habitat for microbial colonization, and may act as carriers for pathogens (i.e., bacteria and viruses). An integrated framework is proposed to better understand the interrelationships between NPs, ecosystems and the human society. In order to fully understand the sources and sinks of NPs, more studies should focus on the total environment, including freshwater, ocean, groundwater, soil and air, and more attempts should be made to explore the aging and aggregation of NPs in environmentally relevant conditions. Considering the fact that naturally-weathered plastic debris may have distinct physicochemical characteristics, future studies should explore the environmental behavior of naturally-aged NPs rather than synthetic polystyrene nanobeads.
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Affiliation(s)
- Liuwei Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Wei-Min Wu
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA
| | - Nanthi S Bolan
- Global Centre for Environmental Remediation, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Yang Li
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Muhan Qin
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Deyi Hou
- School of Environment, Tsinghua University, Beijing 100084, China.
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7
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The Impact of Nanoparticles on Innate Immune Activation by Live Bacteria. Int J Mol Sci 2020; 21:ijms21249695. [PMID: 33353206 PMCID: PMC7766945 DOI: 10.3390/ijms21249695] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 02/07/2023] Open
Abstract
The innate immune system evolved to detect and react against potential dangers such as bacteria, viruses, and environmental particles. The advent of modern technology has exposed innate immune cells, such as monocytes, macrophages, and dendritic cells, to a relatively novel type of particulate matter, i.e., engineered nanoparticles. Nanoparticles are not inherently pathogenic, and yet cases have been described in which specific nanoparticle types can either induce innate/inflammatory responses or modulate the activity of activated innate cells. Many of these studies rely upon activation by agonists of toll-like receptors, such as lipopolysaccharide or peptidoglycan, instead of the more realistic stimulation by whole live organisms. In this review we examine and discuss the effects of nanoparticles on innate immune cells activated by live bacteria. We focus in particular on how nanoparticles may interfere with bacterial processes in the context of innate activation, and confine our scope to the effects due to particles themselves, rather than to molecules adsorbed on the particle surface. Finally, we examine the long-lasting consequences of coexposure to nanoparticles and bacteria, in terms of potential microbiome alterations and innate immune memory, and address nanoparticle-based vaccine strategies against bacterial infection.
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8
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How Reversible Are the Effects of Fumed Silica on Macrophages? A Proteomics-Informed View. NANOMATERIALS 2020; 10:nano10101939. [PMID: 33003391 PMCID: PMC7600894 DOI: 10.3390/nano10101939] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/09/2020] [Accepted: 09/23/2020] [Indexed: 12/16/2022]
Abstract
Synthetic amorphous silica is one of the most used nanomaterials, and numerous toxicological studies have studied its effects. Most of these studies have used an acute exposure mode to investigate the effects immediately after exposure. However, this exposure modality does not allow the investigation of the persistence of the effects, which is a crucial aspect of silica toxicology, as exemplified by crystalline silica. In this paper, we extended the investigations by studying not only the responses immediately after exposure but also after a 72 h post-exposure recovery phase. We used a pyrolytic silica as the test nanomaterial, as this variant of synthetic amorphous silica has been shown to induce a more persistent inflammation in vivo than precipitated silica. To investigate macrophage responses to pyrolytic silica, we used a combination of proteomics and targeted experiments, which allowed us to show that most of the cellular functions that were altered immediately after exposure to pyrolytic silica at a subtoxic dose, such as energy metabolism and cell morphology, returned to normal at the end of the recovery period. However, some alterations, such as the inflammatory responses and some aldehyde detoxification proteins, were persistent. At the proteomic level, other alterations, such as proteins implicated in the endosomal/lysosomal pathway, were also persistent but resulted in normal function, thus suggesting cellular adaptation.
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9
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Boraschi D, Alijagic A, Auguste M, Barbero F, Ferrari E, Hernadi S, Mayall C, Michelini S, Navarro Pacheco NI, Prinelli A, Swart E, Swartzwelter BJ, Bastús NG, Canesi L, Drobne D, Duschl A, Ewart MA, Horejs-Hoeck J, Italiani P, Kemmerling B, Kille P, Prochazkova P, Puntes VF, Spurgeon DJ, Svendsen C, Wilde CJ, Pinsino A. Addressing Nanomaterial Immunosafety by Evaluating Innate Immunity across Living Species. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2000598. [PMID: 32363795 DOI: 10.1002/smll.202000598] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 06/11/2023]
Abstract
The interaction of a living organism with external foreign agents is a central issue for its survival and adaptation to the environment. Nanosafety should be considered within this perspective, and it should be examined that how different organisms interact with engineered nanomaterials (NM) by either mounting a defensive response or by physiologically adapting to them. Herein, the interaction of NM with one of the major biological systems deputed to recognition of and response to foreign challenges, i.e., the immune system, is specifically addressed. The main focus is innate immunity, the only type of immunity in plants, invertebrates, and lower vertebrates, and that coexists with adaptive immunity in higher vertebrates. Because of their presence in the majority of eukaryotic living organisms, innate immune responses can be viewed in a comparative context. In the majority of cases, the interaction of NM with living organisms results in innate immune reactions that eliminate the possible danger with mechanisms that do not lead to damage. While in some cases such interaction may lead to pathological consequences, in some other cases beneficial effects can be identified.
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Affiliation(s)
- Diana Boraschi
- Institute of Biochemistry and Cell Biology, National Research Council, Napoli, 80131, Italy
| | - Andi Alijagic
- Institute for Biomedical Research and Innovation, National Research Council, Palermo, 90146, Italy
| | - Manon Auguste
- Department of Earth, Environment and Life Sciences, University of Genova, Genova, 16126, Italy
| | - Francesco Barbero
- Institut Català de Nanosciència i Nanotecnologia (ICN2), Bellaterra, Barcelona, 08193, Spain
| | - Eleonora Ferrari
- Center for Plant Molecular Biology - ZMBP, Eberhard-Karls University Tübingen, Tübingen, 72076, Germany
| | - Szabolcs Hernadi
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK
| | - Craig Mayall
- Department of Biology, Biotechnical Faculty, University of Liubljana, Ljubljana, 1000, Slovenia
| | - Sara Michelini
- Department of Biosciences, Paris-Lodron University Salzburg, Salzburg, 5020, Austria
| | | | | | - Elmer Swart
- UK Centre for Ecology and Hydrology, Wallingford, OX10 8BB, UK
| | | | - Neus G Bastús
- Institut Català de Nanosciència i Nanotecnologia (ICN2), Bellaterra, Barcelona, 08193, Spain
| | - Laura Canesi
- Department of Earth, Environment and Life Sciences, University of Genova, Genova, 16126, Italy
| | - Damjana Drobne
- Department of Biology, Biotechnical Faculty, University of Liubljana, Ljubljana, 1000, Slovenia
| | - Albert Duschl
- Department of Biosciences, Paris-Lodron University Salzburg, Salzburg, 5020, Austria
| | | | - Jutta Horejs-Hoeck
- Department of Biosciences, Paris-Lodron University Salzburg, Salzburg, 5020, Austria
| | - Paola Italiani
- Institute of Biochemistry and Cell Biology, National Research Council, Napoli, 80131, Italy
| | - Birgit Kemmerling
- Center for Plant Molecular Biology - ZMBP, Eberhard-Karls University Tübingen, Tübingen, 72076, Germany
| | - Peter Kille
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK
| | - Petra Prochazkova
- Institute of Microbiology of the Czech Academy of Sciences, Prague, 142 20, Czech Republic
| | - Victor F Puntes
- Institut Català de Nanosciència i Nanotecnologia (ICN2), Bellaterra, Barcelona, 08193, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, 08010, Spain
- Vall d Hebron, Institut de Recerca (VHIR), Barcelona, 08035, Spain
| | | | - Claus Svendsen
- UK Centre for Ecology and Hydrology, Wallingford, OX10 8BB, UK
| | | | - Annalisa Pinsino
- Institute for Biomedical Research and Innovation, National Research Council, Palermo, 90146, Italy
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10
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Repeated vs. Acute Exposure of RAW264.7 Mouse Macrophages to Silica Nanoparticles: A Bioaccumulation and Functional Change Study. NANOMATERIALS 2020; 10:nano10020215. [PMID: 32012675 PMCID: PMC7074975 DOI: 10.3390/nano10020215] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/20/2020] [Accepted: 01/22/2020] [Indexed: 02/07/2023]
Abstract
Synthetic amorphous silica is used in various applications such as cosmetics, food, or rubber reinforcement. These broad uses increase human exposure, and thus the potential risk related to their short- and long-term toxicity for both consumers and workers. These potential risks have to be investigated, in a global context of multi-exposure, as encountered in human populations. However, most of the in vitro research on the effects of amorphous silica has been carried out in an acute exposure mode, which is not the most relevant when trying to assess the effects of occupational exposure. As a first step, the effects of repeated exposure of macrophages to silica nanomaterials have been investigated. The experiments have been conducted on in vitro macrophage cell line RAW264.7 (cell line from an Abelson murine leukemia virus-induced tumor), as this cell type is an important target cell in toxicology of particulate materials. The bioaccumulation of nanomaterials and the persistence of their effects have been studied. The experiments carried out include the viability assay and functional tests (phagocytosis, NO and reactive oxygen species dosages, and production of pro- and anti-inflammatory cytokines) using flow cytometry, microscopy and spectrophotometry. Accumulation of silica nanoparticles (SiO2 NP) was observed in both exposure scenarii. However, differences in the biological effects between the exposure scenarii have also been observed. For phagocytosis, NO production and Tumor Necrosis Factor (TNF) release, repeated exposure tended to induce fewer effects than acute exposure. Nevertheless, repeated exposure still induces alterations in the macrophage responses and thus represents a scenario to be tested in detail.
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11
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Sanchez-Guzman D, Le Guen P, Villeret B, Sola N, Le Borgne R, Guyard A, Kemmel A, Crestani B, Sallenave JM, Garcia-Verdugo I. Silver nanoparticle-adjuvanted vaccine protects against lethal influenza infection through inducing BALT and IgA-mediated mucosal immunity. Biomaterials 2019; 217:119308. [PMID: 31279103 DOI: 10.1016/j.biomaterials.2019.119308] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/21/2019] [Accepted: 06/25/2019] [Indexed: 12/19/2022]
Abstract
Most of current influenza virus vaccines fail to develop a strong immunity at lung mucosae (site of viral entry) due to sub-optimal vaccination protocols (e.g. inactivated virus administered by parenteral injections). Mucosal immunity could be improved by using locally-delivered vaccines containing appropriate adjuvants. Here we show, in a mouse model, that inclusion of silver nanoparticles (AgNPs) in virus-inactivated flu vaccine resulted in reduction of viral loads and prevention of excessive lung inflammation following influenza infection. Concomitantly, AgNPs enhanced specific IgA secreting plasma cells and antibodies titers, a hallmark of successful mucosal immunity. Moreover, vaccination in the presence of AgNPs but not with gold nanoparticles, protected mice from lethal flu. Compared with other commercial adjuvants (squalene/oil-based emulsion) or silver salts, AgNPs stimulated stronger antigen specific IgA production with lower toxicity by promoting bronchus-associated lymphoid tissue (BALT) neogenesis, and acted as a bona fide mucosal adjuvant.
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Affiliation(s)
- Daniel Sanchez-Guzman
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France
| | - Pierre Le Guen
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France; Department of Pneumology A, AP-HP, Groupe Hospitalier Bichat-Claude Bernard, Paris, 75018, Paris, France
| | - Berengere Villeret
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France
| | - Nuria Sola
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France
| | - Remi Le Borgne
- ImagoSeine, Electron Microscopy Facility, Institut Jacques Monod, CNRS UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75205, Cedex 13, Paris, France
| | - Alice Guyard
- Department of Pathology, AP-HP, Groupe Hospitalier Bichat-Claude Bernard, Paris, 75018, Paris, France
| | - Alix Kemmel
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France
| | - Bruno Crestani
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France; Department of Pneumology A, AP-HP, Groupe Hospitalier Bichat-Claude Bernard, Paris, 75018, Paris, France
| | - Jean-Michel Sallenave
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France
| | - Ignacio Garcia-Verdugo
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation and Remodeling), Université Paris Diderot, Sorbonne Paris Cité, 75018, Paris, France.
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12
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Kan H, Pan D, Castranova V. Engineered nanoparticle exposure and cardiovascular effects: the role of a neuronal-regulated pathway. Inhal Toxicol 2019; 30:335-342. [PMID: 30604639 DOI: 10.1080/08958378.2018.1535634] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Human and animal studies have confirmed that inhalation of particles from ambient air or occupational settings not only causes pathophysiological changes in the respiratory system, but causes cardiovascular effects as well. At an equal mass lung burden, nanoparticles are more potent in causing systemic microvascular dysfunction than fine particles of similar composition. Thus, accumulated evidence from animal studies has led to heightened concerns about the potential short- and long-term deleterious effects of inhalation of engineered nanoparticles on the cardiovascular system. This review highlights the new observations from animal studies, which document the adverse effects of pulmonary exposure to engineered nanoparticles on the cardiovascular system and elucidate the potential mechanisms involved in regulation of cardiovascular function, in particular, how the neuronal system plays a role and reacts to pulmonary nanoparticle exposure based on both in vivo and in vitro studies. In addition, this review also discusses the possible influence of altered autonomic nervous activity on preexisting cardiovascular conditions. Whether engineered nanoparticle exposure serves as a risk factor in the development of cardiovascular diseases warrants further investigation.
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Affiliation(s)
- H Kan
- a Health Effects Laboratory Division , National Institute for Occupational Safety and Health , Morgantown , WV , USA.,b Department of Pharmaceutical Sciences , West Virginia University , Morgantown , WV , USA
| | - D Pan
- a Health Effects Laboratory Division , National Institute for Occupational Safety and Health , Morgantown , WV , USA
| | - V Castranova
- b Department of Pharmaceutical Sciences , West Virginia University , Morgantown , WV , USA
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13
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You R, Ho YS, Hung CHL, Liu Y, Huang CX, Chan HN, Ho SL, Lui SY, Li HW, Chang RCC. Silica nanoparticles induce neurodegeneration-like changes in behavior, neuropathology, and affect synapse through MAPK activation. Part Fibre Toxicol 2018; 15:28. [PMID: 29970116 PMCID: PMC6029039 DOI: 10.1186/s12989-018-0263-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/29/2018] [Indexed: 12/27/2022] Open
Abstract
Background Silica nanoparticles (SiO2-NPs) are naturally enriched and broadly utilized in the manufacturing industry. While previous studies have demonstrated toxicity in neuronal cell lines after SiO2-NPs exposure, the role of SiO2-NPs in neurodegeneration is largely unknown. Here, we evaluated the effects of SiO2-NPs-exposure on behavior, neuropathology, and synapse in young adult mice and primary cortical neuron cultures. Results Male C57BL/6 N mice (3 months old) were exposed to either vehicle (sterile PBS) or fluorescein isothiocyanate (FITC)-tagged SiO2-NPs (NP) using intranasal instillation. Behavioral tests were performed after 1 and 2 months of exposure. We observed decreased social activity at both time points as well as anxiety and cognitive impairment after 2 months in the NP-exposed mice. NP deposition was primarily detected in the medial prefrontal cortex and the hippocampus. Neurodegeneration-like pathological changes, including reduced Nissl staining, increased tau phosphorylation, and neuroinflammation, were also present in the brains of NP-exposed mice. Furthermore, we observed NP-induced impairment in exocytosis along with decreased synapsin I and increased synaptophysin expression in the synaptosome fractions isolated from the frontal cortex as well as primary neuronal cultures. Extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) were also activated in the frontal cortex of NP-exposed mice. Moreover, inhibition of ERK activation prevented NP-mediated changes in exocytosis in cultured neurons, highlighting a key role in the changes induced by NP exposure. Conclusions Intranasal instillation of SiO2-NPs results in mood dysfunction and cognitive impairment in young adult mice and causes neurodegeneration-like pathology and synaptic changes via ERK activation. Electronic supplementary material The online version of this article (10.1186/s12989-018-0263-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ran You
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China.,Present address: Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, 210008, China
| | - Yuen-Shan Ho
- School of Nursing, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, SAR, China
| | - Clara Hiu-Ling Hung
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China
| | - Yan Liu
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China
| | - Chun-Xia Huang
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China
| | - Hei-Nga Chan
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, SAR, China
| | - See-Lok Ho
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, SAR, China
| | - Sheung-Yeung Lui
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, SAR, China
| | - Hung-Wing Li
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong, SAR, China
| | - Raymond Chuen-Chung Chang
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China. .,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China. .,School of Biomedical Sciences, Rm. L4-49, Laboratory Block, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong.
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14
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Wang X, Gong J, Gui Z, Hu T, Xu X. Halloysite nanotubes-induced Al accumulation and oxidative damage in liver of mice after 30-day repeated oral administration. ENVIRONMENTAL TOXICOLOGY 2018; 33:623-630. [PMID: 29457689 DOI: 10.1002/tox.22543] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 01/22/2018] [Accepted: 01/27/2018] [Indexed: 06/08/2023]
Abstract
Halloysite (Al2 Si2 O5 (OH)4 ·nH2 O) nanotubes (HNTs) are natural clay materials and widely applied in many fields due to their natural hollow tubular structures. Many in vitro studies indicate that HNTs exhibit a high level of biocompatibility, however the in vivo toxicity of HNTs remains unclear. The objective of this study was to assess the hepatic toxicity of the purified HNTs in mice via oral route. The purified HNTs were orally administered to mice at 5, 50, and 300 mg/kg body weight (BW) every day for 30 days. Oral administration of HNTs stimulated the growth of the mice at the low dose (5 mg/kg BW) with no liver toxicity, but inhibited the growth of the mice at the middle (50 mg/kg BW) and high (300 mg/kg BW) doses. In addition, oral administration of HNTs at the high dose caused Al accumulation in the liver but had no marked effect on the Si content in the organ. The Al accumulation caused significant oxidative stress in the liver, which induced hepatic dysfunction and histopathologic changes. These findings demonstrated that Al accumulation-induced oxidative stress played an important role in the oral HNTs-caused liver injury.
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Affiliation(s)
- Xue Wang
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Jiachun Gong
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Zongxiang Gui
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Tingting Hu
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | - Xiaolong Xu
- Department of Chemistry, University of Science and Technology of China, Hefei, 230026, People's Republic of China
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15
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Wang X, Gong J, Rong R, Gui Z, Hu T, Xu X. Halloysite Nanotubes-Induced Al Accumulation and Fibrotic Response in Lung of Mice after 30-Day Repeated Oral Administration. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:2925-2933. [PMID: 29470912 DOI: 10.1021/acs.jafc.7b04615] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Natural halloysite (Al2Si2O5(OH)4· nH2O) nanotubes (HNT) are clay materials with hollow tubular structure and are widely applied in many fields. Many in vitro studies indicate that HNTs exhibit a high level of biocompatibility; however, the in vivo toxicity of HNTs remains unclear. In this study, the biodistribution and pulmonary toxicity of the purified HNTs in mice were investigated after intragastric administration for 30 days. HNTs have high stability in biological conditions. Oral administration of HNTs caused significant Al accumulation predominantly in the lung with relative slight effects on Si biodistribution. Oral administration of HNTs stimulated the growth of the mice at low dose (5 mg/kg BW) with no pulmonary toxicity but inhibited the mouse growth and resulted in oxidative stress and inflammation in lung at high dose (50 mg/kg BW). In addition, oral HNTs at high dose could be absorbed from the gastrointestinal tract and deposited in lung and could also induce pulmonary fibrosis.
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Affiliation(s)
- Xue Wang
- Department of Chemistry , University of Science and Technology of China , Hefei , 230026 , P. R. China
| | - Jiachun Gong
- Department of Chemistry , University of Science and Technology of China , Hefei , 230026 , P. R. China
| | - Rui Rong
- Department of Chemistry , University of Science and Technology of China , Hefei , 230026 , P. R. China
| | - Zongxiang Gui
- Department of Chemistry , University of Science and Technology of China , Hefei , 230026 , P. R. China
| | - Tingting Hu
- Department of Chemistry , University of Science and Technology of China , Hefei , 230026 , P. R. China
| | - Xiaolong Xu
- Department of Chemistry , University of Science and Technology of China , Hefei , 230026 , P. R. China
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16
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Villeret B, Dieu A, Straube M, Solhonne B, Miklavc P, Hamadi S, Le Borgne R, Mailleux A, Norel X, Aerts J, Diallo D, Rouzet F, Dietl P, Sallenave JM, Garcia-Verdugo I. Silver Nanoparticles Impair Retinoic Acid-Inducible Gene I-Mediated Mitochondrial Antiviral Immunity by Blocking the Autophagic Flux in Lung Epithelial Cells. ACS NANO 2018; 12:1188-1202. [PMID: 29357226 DOI: 10.1021/acsnano.7b06934] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Silver nanoparticles (AgNPs) are microbicidal agents which could be potentially used as an alternative to antivirals to treat human infectious diseases, especially influenza virus infections where antivirals have generally proven unsuccessful. However, concerns about the use of AgNPs on humans arise from their potential toxicity, although mechanisms are not well-understood. We show here, in the context of an influenza virus infection of lung epithelial cells, that AgNPs down-regulated influenza induced CCL-5 and -IFN-β release (two cytokines important in antiviral immunity) through RIG-I inhibition, while enhancing IL-8 production, a cytokine important for mobilizing host antibacterial responses. AgNPs activity was independent of coating and was not observed with gold nanoparticles. Down-stream analysis indicated that AgNPs disorganized the mitochondrial network and prevented the antiviral IRF-7 transcription factor influx into the nucleus. Importantly, we showed that the modulation of RIG-I-IRF-7 pathway was concomitant with inhibition of either classical or alternative autophagy (ATG-5- and Rab-9 dependent, respectively), depending on the epithelial cell type used. Altogether, this demonstration of a AgNPs-mediated functional dichotomy (down-regulation of IFN-dependent antiviral responses and up-regulation of IL-8-dependent antibacterial responses) may have practical implications for their use in the clinic.
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Affiliation(s)
- Berengere Villeret
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation, and Remodeling), University Paris Diderot , Sorbonne Paris Cité, 75018 Paris, France
| | - Alexandra Dieu
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation, and Remodeling), University Paris Diderot , Sorbonne Paris Cité, 75018 Paris, France
| | - Marjolene Straube
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation, and Remodeling), University Paris Diderot , Sorbonne Paris Cité, 75018 Paris, France
| | - Brigitte Solhonne
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation, and Remodeling), University Paris Diderot , Sorbonne Paris Cité, 75018 Paris, France
| | - Pika Miklavc
- Biomedical Research Centre, School of Environment and Life Sciences, University of Salford , Salford, United Kingdom
| | - Sena Hamadi
- Université Paris Est, ICMPE (UMR7182), CNRS, UPEC , F-94320 Thiais, France
| | - Rémi Le Borgne
- ImagoSeine, Electron Microscopy Facility, Institut Jacques Monod, CNRS UMR 7592, Université Paris Diderot , Sorbonne Paris Cité, 75205 Cedex 13 Paris, France
| | - Arnaud Mailleux
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation, and Remodeling), University Paris Diderot , Sorbonne Paris Cité, 75018 Paris, France
| | - Xavier Norel
- Inserm U1148, UMR-S1148, University Paris Nord , 75018 Paris, France
| | - Joel Aerts
- AP-HP, Groupe Hospitalier Bichat-Claude Bernard, Service de Médecine Nucléaire, Université Denis Diderot-Paris 7, U1148, Inserm , 75013 Paris, France
| | - Devy Diallo
- AP-HP, Groupe Hospitalier Bichat-Claude Bernard, Service de Médecine Nucléaire, Université Denis Diderot-Paris 7, U1148, Inserm , 75013 Paris, France
| | - Francois Rouzet
- AP-HP, Groupe Hospitalier Bichat-Claude Bernard, Service de Médecine Nucléaire, Université Denis Diderot-Paris 7, U1148, Inserm , 75013 Paris, France
| | - Paul Dietl
- Institute of General Physiology, University of Ulm , Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Jean-Michel Sallenave
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation, and Remodeling), University Paris Diderot , Sorbonne Paris Cité, 75018 Paris, France
| | - Ignacio Garcia-Verdugo
- INSERM, UMR U1152, Laboratoire d'Excellence Inflamex, Département Hospitalo-Universitaire FIRE (Fibrosis, Inflammation, and Remodeling), University Paris Diderot , Sorbonne Paris Cité, 75018 Paris, France
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17
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Sanchez A, Alvarez JL, Demydenko K, Jung C, Alpizar YA, Alvarez-Collazo J, Cokic SM, Valverde MA, Hoet PH, Talavera K. Silica nanoparticles inhibit the cation channel TRPV4 in airway epithelial cells. Part Fibre Toxicol 2017; 14:43. [PMID: 29100528 PMCID: PMC5670529 DOI: 10.1186/s12989-017-0224-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 10/27/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Silica nanoparticles (SiNPs) have numerous beneficial properties and are extensively used in cosmetics and food industries as anti-caking, densifying and hydrophobic agents. However, the increasing exposure levels experienced by the general population and the ability of SiNPs to penetrate cells and tissues have raised concerns about possible toxic effects of this material. Although SiNPs are known to affect the function of the airway epithelium, the molecular targets of these particles remain largely unknown. Given that SiNPs interact with the plasma membrane of epithelial cells we hypothesized that they may affect the function of Transient Receptor Potential Vanilloid 4 (TRPV4), a cation-permeable channel that regulates epithelial barrier function. The main aims of this study were to evaluate the effects of SiNPs on the activation of TRPV4 and to determine whether these alter the positive modulatory action of this channel on the ciliary beat frequency in airway epithelial cells. RESULTS Using fluorometric measurements of intracellular Ca2+ concentration ([Ca2+]i) we found that SiNPs inhibit activation of TRPV4 by the synthetic agonist GSK1016790A in cultured human airway epithelial cells 16HBE and in primary cultured mouse tracheobronchial epithelial cells. Inhibition of TRPV4 by SiNPs was confirmed in intracellular Ca2+ imaging and whole-cell patch-clamp experiments performed in HEK293T cells over-expressing this channel. In addition to these effects, SiNPs were found to induce a significant increase in basal [Ca2+]i, but in a TRPV4-independent manner. SiNPs enhanced the activation of the capsaicin receptor TRPV1, demonstrating that these particles have a specific inhibitory action on TRPV4 activation. Finally, we found that SiNPs abrogate the increase in ciliary beat frequency induced by TRPV4 activation in mouse airway epithelial cells. CONCLUSIONS Our results show that SiNPs inhibit TRPV4 activation, and that this effect may impair the positive modulatory action of the stimulation of this channel on the ciliary function in airway epithelial cells. These findings unveil the cation channel TRPV4 as a primary molecular target of SiNPs.
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Affiliation(s)
- Alicia Sanchez
- Department of Cellular and Molecular Medicine, Laboratory of Ion Channel Research, KU Leuven; VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Julio L Alvarez
- Department of Cellular and Molecular Medicine, Laboratory of Ion Channel Research, KU Leuven; VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Kateryna Demydenko
- Department of Cellular and Molecular Medicine, Laboratory of Ion Channel Research, KU Leuven; VIB Center for Brain & Disease Research, Leuven, Belgium.,Present address: Department of Cardiovascular Sciences, Laboratory of Experimental Cardiology, Leuven, KU, Belgium
| | - Carole Jung
- Department of Experimental and Health Sciences, Laboratory of Molecular Physiology and Channelopathies, Universitat Pompeu Fabra, Barcelona, Spain
| | - Yeranddy A Alpizar
- Department of Cellular and Molecular Medicine, Laboratory of Ion Channel Research, KU Leuven; VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Julio Alvarez-Collazo
- Department of Cellular and Molecular Medicine, Laboratory of Ion Channel Research, KU Leuven; VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Stevan M Cokic
- KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven & Dentistry University Hospitals Leuven, Leuven, Belgium
| | - Miguel A Valverde
- Department of Experimental and Health Sciences, Laboratory of Molecular Physiology and Channelopathies, Universitat Pompeu Fabra, Barcelona, Spain
| | - Peter H Hoet
- Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
| | - Karel Talavera
- Department of Cellular and Molecular Medicine, Laboratory of Ion Channel Research, KU Leuven; VIB Center for Brain & Disease Research, Leuven, Belgium.
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18
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Mebert AM, Baglole CJ, Desimone MF, Maysinger D. Nanoengineered silica: Properties, applications and toxicity. Food Chem Toxicol 2017; 109:753-770. [DOI: 10.1016/j.fct.2017.05.054] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 05/26/2017] [Indexed: 02/06/2023]
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19
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da Luz CM, Boyles MSP, Falagan-Lotsch P, Pereira MR, Tutumi HR, de Oliveira Santos E, Martins NB, Himly M, Sommer A, Foissner I, Duschl A, Granjeiro JM, Leite PEC. Poly-lactic acid nanoparticles (PLA-NP) promote physiological modifications in lung epithelial cells and are internalized by clathrin-coated pits and lipid rafts. J Nanobiotechnology 2017; 15:11. [PMID: 28143572 PMCID: PMC5282631 DOI: 10.1186/s12951-016-0238-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 12/03/2016] [Indexed: 02/07/2023] Open
Abstract
Background Poly-lactic acid nanoparticles (PLA-NP) are a type of polymeric NP, frequently used as nanomedicines, which have advantages over metallic NP such as the ability to maintain therapeutic drug levels for sustained periods of time. Despite PLA-NP being considered biocompatible, data concerning alterations in cellular physiology are scarce. Methods We conducted an extensive evaluation of PLA-NP biocompatibility in human lung epithelial A549 cells using high throughput screening and more complex methodologies. These included measurements of cytotoxicity, cell viability, immunomodulatory potential, and effects upon the cells’ proteome. We used non- and green-fluorescent PLA-NP with 63 and 66 nm diameters, respectively. Cells were exposed with concentrations of 2, 20, 100 and 200 µg/mL, for 24, 48 and 72 h, in most experiments. Moreover, possible endocytic mechanisms of internalization of PLA-NP were investigated, such as those involving caveolae, lipid rafts, macropinocytosis and clathrin-coated pits. Results Cell viability and proliferation were not altered in response to PLA-NP. Multiplex analysis of secreted mediators revealed a low-level reduction of IL-12p70 and vascular epidermal growth factor (VEGF) in response to PLA-NP, while all other mediators assessed were unaffected. However, changes to the cells’ proteome were observed in response to PLA-NP, and, additionally, the cellular stress marker miR155 was found to reduce. In dual exposures of staurosporine (STS) with PLA-NP, PLA-NP enhanced susceptibility to STS-induced cell death. Finally, PLA-NP were rapidly internalized in association with clathrin-coated pits, and, to a lesser extent, with lipid rafts. Conclusions These data demonstrate that PLA-NP are internalized and, in general, tolerated by A549 cells, with no cytotoxicity and no secretion of pro-inflammatory mediators. However, PLA-NP exposure may induce modification of biological functions of A549 cells, which should be considered when designing drug delivery systems. Moreover, the pathways of PLA-NP internalization we detected could contribute to the improvement of selective uptake strategies. Electronic supplementary material The online version of this article (doi:10.1186/s12951-016-0238-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Camila Macedo da Luz
- Laboratory of Bioengineering and in Vitro Toxicology, Directory of Metrology Applied to Life Sciences (Dimav), National Institute of Metrology Quality and Technology (INMETRO), Duque De Caxias, RJ, Brazil
| | - Matthew Samuel Powys Boyles
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria.,Heriot-Watt University, Edinburg, UK
| | - Priscila Falagan-Lotsch
- Laboratory of Bioengineering and in Vitro Toxicology, Directory of Metrology Applied to Life Sciences (Dimav), National Institute of Metrology Quality and Technology (INMETRO), Duque De Caxias, RJ, Brazil
| | - Mariana Rodrigues Pereira
- Laboratory of Chemical Signaling in Nervous System, Biology Institute, Fluminense Federal University, Niteroi, RJ, Brazil
| | - Henrique Rudolf Tutumi
- Laboratory of Bioengineering and in Vitro Toxicology, Directory of Metrology Applied to Life Sciences (Dimav), National Institute of Metrology Quality and Technology (INMETRO), Duque De Caxias, RJ, Brazil
| | - Eidy de Oliveira Santos
- Laboratory of Bioengineering and in Vitro Toxicology, Directory of Metrology Applied to Life Sciences (Dimav), National Institute of Metrology Quality and Technology (INMETRO), Duque De Caxias, RJ, Brazil.,Laboratory of Biochemistry, State University Center of West Zone (UEZO), Rio de Janeiro, RJ, Brazil
| | - Nathalia Balthazar Martins
- Laboratory of Bioengineering and in Vitro Toxicology, Directory of Metrology Applied to Life Sciences (Dimav), National Institute of Metrology Quality and Technology (INMETRO), Duque De Caxias, RJ, Brazil
| | - Martin Himly
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Aniela Sommer
- Department of Cell Biology, University of Salzburg, Salzburg, Austria
| | - Ilse Foissner
- Department of Cell Biology, University of Salzburg, Salzburg, Austria
| | - Albert Duschl
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - José Mauro Granjeiro
- Laboratory of Bioengineering and in Vitro Toxicology, Directory of Metrology Applied to Life Sciences (Dimav), National Institute of Metrology Quality and Technology (INMETRO), Duque De Caxias, RJ, Brazil.,Dental School, Fluminense Federal University, Niteroi, RJ, Brazil
| | - Paulo Emílio Corrêa Leite
- Laboratory of Bioengineering and in Vitro Toxicology, Directory of Metrology Applied to Life Sciences (Dimav), National Institute of Metrology Quality and Technology (INMETRO), Duque De Caxias, RJ, Brazil. .,, Av. Nossa Senhora das Gracas 50, LABET - Dimav, Predio 27, Duque de Caxias, Xerem, Rio de Janeiro, 25250-020, Brazil.
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20
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Yang M, Jing L, Wang J, Yu Y, Cao L, Zhang L, Zhou X, Sun Z. Macrophages participate in local and systemic inflammation induced by amorphous silica nanoparticles through intratracheal instillation. Int J Nanomedicine 2016; 11:6217-6228. [PMID: 27920528 PMCID: PMC5125762 DOI: 10.2147/ijn.s116492] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Silica nanoparticles (SiNPs) are amongst the most commonly used materials in the field of nanomedicine and, therefore, their influence on organisms has drawn increasing attention in recent years. Most reports have focused on the single tissue reactions induced by SiNPs. Herein, the reaction of primary organs to SiNPs following intratracheal instillation in mice was analyzed by histopathology and ultrastructure observation. Following elucidation of the role of macrophages in local and systemic inflammation, the underlying mechanisms were explored using a macrophage cell line in vitro. The results suggest that macrophages swallow the SiNPs and secrete inflammatory factors by activating the NLRP3 inflammasome, thus participating in local and systemic inflammation.
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Affiliation(s)
- Man Yang
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
| | - Li Jing
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
| | - Ji Wang
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
| | - Yang Yu
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
| | - Lige Cao
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
| | - Lianshuang Zhang
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
| | - Xianqing Zhou
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
| | - Zhiwei Sun
- School of Public Health, Capital Medical University, Beijing, People's Republic of China; Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, People's Republic of China
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Boyles MSP, Ranninger C, Reischl R, Rurik M, Tessadri R, Kohlbacher O, Duschl A, Huber CG. Copper oxide nanoparticle toxicity profiling using untargeted metabolomics. Part Fibre Toxicol 2016; 13:49. [PMID: 27609141 PMCID: PMC5017021 DOI: 10.1186/s12989-016-0160-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 08/26/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The rapidly increasing number of engineered nanoparticles (NPs), and products containing NPs, raises concerns for human exposure and safety. With this increasing, and ever changing, catalogue of NPs it is becoming more difficult to adequately assess the toxic potential of new materials in a timely fashion. It is therefore important to develop methods which can provide high-throughput screening of biological responses. The use of omics technologies, including metabolomics, can play a vital role in this process by providing relatively fast, comprehensive, and cost-effective assessment of cellular responses. These techniques thus provide the opportunity to identify specific toxicity pathways and to generate hypotheses on how to reduce or abolish toxicity. RESULTS We have used untargeted metabolome analysis to determine differentially expressed metabolites in human lung epithelial cells (A549) exposed to copper oxide nanoparticles (CuO NPs). Toxicity hypotheses were then generated based on the affected pathways, and critically tested using more conventional biochemical and cellular assays. CuO NPs induced regulation of metabolites involved in oxidative stress, hypertonic stress, and apoptosis. The involvement of oxidative stress was clarified more easily than apoptosis, which involved control experiments to confirm specific metabolites that could be used as standard markers for apoptosis; based on this we tentatively propose methylnicotinamide as a generic metabolic marker for apoptosis. CONCLUSIONS Our findings are well aligned with the current literature on CuO NP toxicity. We thus believe that untargeted metabolomics profiling is a suitable tool for NP toxicity screening and hypothesis generation.
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Affiliation(s)
- Matthew S. P. Boyles
- Department of Molecular Biology, Division of Allergy and Immunology, University of Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria
| | - Christina Ranninger
- Department of Molecular Biology, Division of Chemistry and Bioanalytics, University of Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria
| | - Roland Reischl
- Department of Molecular Biology, Division of Chemistry and Bioanalytics, University of Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria
| | - Marc Rurik
- Center for Bioinformatics, University of Tübingen, Tübingen, Germany ,Department of Computer Science, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - Richard Tessadri
- Faculty of Geo- and Atmospheric Science, Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria
| | - Oliver Kohlbacher
- Center for Bioinformatics, University of Tübingen, Tübingen, Germany ,Department of Computer Science, University of Tübingen, Sand 14, 72076 Tübingen, Germany ,Quantitative Biology Center, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany ,Faculty of Medicine, University of Tübingen, Geissweg 3, 72076 Tübingen, Germany ,Max Planck Institute for Developmental Biology, Spemannstraße 35, 72076 Tübingen, Germany
| | - Albert Duschl
- Department of Molecular Biology, Division of Allergy and Immunology, University of Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria
| | - Christian G. Huber
- Department of Molecular Biology, Division of Chemistry and Bioanalytics, University of Salzburg, Hellbrunner Strasse 34, 5020 Salzburg, Austria
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22
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Agnihothram SS, Vermudez SA, Mullis L, Townsend TA, Manjanatha MG, Azevedo MP. Silicon Dioxide Impedes Antiviral Response and Causes Genotoxic Insult During Calicivirus Replication. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2016; 16:7720-7730. [PMID: 27547159 PMCID: PMC4986603 DOI: 10.1166/jnn.2016.12828] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Noroviruses (NoV) are the leading cause of nonbacterial gastroenteritis in humans, and replicate extensively in the human gastrointestinal (GI) tract. Silica (also known as silicon dioxide, SiO2) nanoparticles (NPs) used in processed foods, dairy products, and beverages also accumulate in the GI tract. We investigated the effect of silica NPs on NoV replication and host cell response during virus infection, using murine norovirus (MNV-1) infection of RAW 264.7 murine macrophages. Pretreatment with 10 μg/ml silica significantly reduced the viability of macrophages, but no cumulative effects on viability of macrophages were observed with MNV-1 infection. No difference was observed between exposure to control or silica NPs on either the quantity of viral genome copies or the production of infectious virus in macrophages infected with MNV-1. Silica NPs reduced the ability of macrophages to upregulate genes encoding bone morphogenic proteins (BMPs), chemokine ligands and cytokines for which expression levels were otherwise found to be upregulated in response to MNV-1 infection. Furthermore, silica NPs reduced the levels of proinflammatory cytokines secreted by macrophages in response to MNV infection. Finally, silica NPs with MNV-1 infection produced a genotoxic insult to macrophages. Strikingly, this genotoxic insult was also found to occur as a synergistic effect of silica NPs and feline calicivirus infection in feline kidney epithelial cells. Taken together, our study suggests important safety considerations related to reducing exposure to silica NPs affecting the GI tract in individuals infected with NoVs and possibly other foodborne viruses.
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Affiliation(s)
- Sudhakar S Agnihothram
- United States Food and Drug Administration, National Center for Toxicological Research (NCTR), Division of Microbiology, Honolulu, Hawaii, 96816, USA
| | - Sheryl Anne Vermudez
- United States Food and Drug Administration, National Center for Toxicological Research (NCTR), Division of Microbiology, Honolulu, Hawaii, 96816, USA; Chaminade University of Honolulu, Honolulu, Hawaii, 96816, USA
| | - Lisa Mullis
- United States Food and Drug Administration, National Center for Toxicological Research (NCTR), Division of Microbiology, Honolulu, Hawaii, 96816, USA
| | - Todd A Townsend
- United States Food and Drug Administration, National Center for Toxicological Research (NCTR), Division of Genetic and Molecular Toxicology, Honolulu, Hawaii, 96816, USA
| | - Mugimane G Manjanatha
- United States Food and Drug Administration, National Center for Toxicological Research (NCTR), Division of Genetic and Molecular Toxicology, Honolulu, Hawaii, 96816, USA
| | - Marli P Azevedo
- United States Food and Drug Administration, National Center for Toxicological Research (NCTR), Division of Microbiology, Honolulu, Hawaii, 96816, USA
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23
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Beamer GL, Seaver BP, Jessop F, Shepherd DM, Beamer CA. Acute Exposure to Crystalline Silica Reduces Macrophage Activation in Response to Bacterial Lipoproteins. Front Immunol 2016; 7:49. [PMID: 26913035 PMCID: PMC4753301 DOI: 10.3389/fimmu.2016.00049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 02/01/2016] [Indexed: 11/13/2022] Open
Abstract
Numerous studies have examined the relationship between alveolar macrophages (AMs) and crystalline silica (SiO2) using in vitro and in vivo immunotoxicity models; however, exactly how exposure to SiO2 alters the functionality of AM and the potential consequences for immunity to respiratory pathogens remains largely unknown. Because recognition and clearance of inhaled particulates and microbes are largely mediated by pattern recognition receptors (PRRs) on the surface of AM, we hypothesized that exposure to SiO2 limits the ability of AM to respond to bacterial challenge by altering PRR expression. Alveolar and bone marrow-derived macrophages downregulate TLR2 expression following acute SiO2 exposure (e.g., 4 h). Interestingly, these responses were dependent on interactions between SiO2 and the class A scavenger receptor CD204, but not MARCO. Furthermore, SiO2 exposure decreased uptake of fluorescently labeled Pam2CSK4 and Pam3CSK4, resulting in reduced secretion of IL-1β, but not IL-6. Collectively, our data suggest that SiO2 exposure alters AM phenotype, which in turn affects their ability to uptake and respond to bacterial lipoproteins.
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Affiliation(s)
- Gillian L Beamer
- Department of Infectious Diseases and Global Health, Cummings School of Veterinary Medicine, Tufts University , North Grafton, MA , USA
| | - Benjamin P Seaver
- Department of Biomedical and Pharmaceutical Sciences, University of Montana , Missoula, MT , USA
| | - Forrest Jessop
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT, USA; Center for Environmental Health Sciences, Missoula, MT, USA
| | - David M Shepherd
- Department of Biomedical and Pharmaceutical Sciences, University of Montana , Missoula, MT , USA
| | - Celine A Beamer
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, MT, USA; Center for Biomolecular Structure and Dynamics, Missoula, MT, USA
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24
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Dosunmu E, Chaudhari AA, Singh SR, Dennis VA, Pillai SR. Silver-coated carbon nanotubes downregulate the expression of Pseudomonas aeruginosa virulence genes: a potential mechanism for their antimicrobial effect. Int J Nanomedicine 2015; 10:5025-34. [PMID: 26346483 PMCID: PMC4531027 DOI: 10.2147/ijn.s85219] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The antimicrobial activity of silver-coated carbon nanotubes (AgCNTs) and their potential mode of action against mucoid and nonmucoid strains of Pseudomonas aeruginosa was investigated in vitro. The results showed that AgCNTs exhibited antimicrobial activity against both strains with minimum inhibitory concentrations of approximately 8 µg/mL, indicating a high sensitivity of P. aeruginosa to AgCNTs. AgCNTs were also bactericidal against both strains at the same minimum inhibitory concentration. Scanning and transmission electron-microscopy studies further revealed that a majority of the cells treated with AgCNTs transformed from smooth rod-shape morphology to disintegrated cells with broken/damaged membranes, resulting in leakage of cytoplasmic contents to produce ghost cells. The molecular effects of AgCNTs on P. aeruginosa genes involved in virulence and pathogenicity, stress response, and efflux pumps were evaluated for changes in their expression. Quantitative real-time PCR (qRT-PCR) showed that after exposure to AgCNTs, the expression levels of the rpoS, rsmZ, and oprD genes were significantly downregulated in both strains of P. aeruginosa compared to the untreated samples. These results suggest that the mechanism of action of AgCNTs may be attributed to their effect on cell-membrane integrity, downregulation of virulence-gene expression, and induction of general and oxidative stress in P. aeruginosa.
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Affiliation(s)
- Ejovwoke Dosunmu
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, USA
| | - Atul A Chaudhari
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, USA
| | - Shree R Singh
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, USA
| | - Vida A Dennis
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, USA
| | - Shreekumar R Pillai
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, AL, USA
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