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Worden CP, Hicks KB, Hackman TG, Yarbrough WG, Kimple AJ, Farzal Z. The Toxicological Effects of e-Cigarette Use in the Upper Airway: A Scoping Review. Otolaryngol Head Neck Surg 2024; 170:1246-1269. [PMID: 38353408 PMCID: PMC11060921 DOI: 10.1002/ohn.652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/07/2023] [Accepted: 12/30/2023] [Indexed: 05/02/2024]
Abstract
OBJECTIVE While evidence continues to emerge on the negative health effects of electronic cigarettes (e-cigarettes) on the lungs, little is known regarding their deleterious effects on the upper airway. The purpose of this review is to summarize the toxicological effects of e-cigarettes, and their components, on the upper airway. DATA SOURCES PubMed, SCOPUS, EMBASE databases. REVIEW METHODS Systematic searches were performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines from 2003 to 2023. Studies were included if they investigated the toxicological effects of e-cigarette exposure on human or animal upper airway tissue. Two authors independently screened, reviewed, and appraised all included articles. RESULTS A total of 822 unique articles were identified, of which 53 met inclusion criteria and spanned subsites including the oral cavity (22/53 studies), nasal cavity/nasopharynx (13/53), multiple sites (10/53), larynx (5/53), trachea (2/53), and oropharynx (1/53). The most commonly observed consequences of e-cigarette use on the upper airway included: proinflammatory (15/53 studies), histological (13/53), cytotoxicity (11/53), genotoxicity (11/53), and procarcinogenic (6/53). E-cigarette humectants independently induced toxicity at multiple upper airway subsites, however, effects were generally amplified when flavoring(s) and/or nicotine were added. Across almost all studies, exposure to cigarette smoke exhibited increased toxicity in the upper airway compared with exposure to e-cigarette vapor. CONCLUSION Current data suggest that while e-cigarettes are generally less harmful than traditional cigarettes, they possess a distinct toxicological profile that is enhanced upon the addition of flavoring(s) and/or nicotine. Future investigations into underexamined subsites, such as the oropharynx and hypopharynx, are needed to comprehensively understand the effects of e-cigarettes on the upper airway.
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Affiliation(s)
- Cameron P Worden
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Kayla B Hicks
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Trevor G Hackman
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Wendell G Yarbrough
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, Division of Virology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Adam J Kimple
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, Division of Virology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Cystic Fibrosis Center, Marsico Lung Institute, Department of Medicine, Division of Pulmonary, Critical Care Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Zainab Farzal
- Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Emma Sarles S, Hensel EC, Terry J, Nuss C, Robinson RJ. Flow Rate and Wall Shear Stress Characterization of a Biomimetic Aerosol Exposure System. J Biomech Eng 2024; 146:045001. [PMID: 38270928 PMCID: PMC10983703 DOI: 10.1115/1.4064549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 01/16/2024] [Accepted: 01/18/2024] [Indexed: 01/26/2024]
Abstract
Current in vitro emissions and exposure systems lack biomimicry, use unrealistic flow conditions, produce unrealistic dose, and provide inaccurate biomechanical cues to cell cultures, limiting ability to correlate in vitro outcomes with in vivo health effects. A biomimetic in vitro system capable of puffing aerosol and clean air inhalation may empower researchers to investigate complex questions related to lung injury and disease. A biomimetic aerosol exposure system (BAES), including an electronic cigarette adapter, oral cavity module (OCM), and bifurcated exposure chamber (BEC) was designed and manufactured. The fraction of aerosol deposited in transit to a filter pad or lost as volatiles was 0.116±0.021 in a traditional emissions setup versus 0.098 ± 0.015 with the adapter. The observed flowrate was within 5% of programed flowrate for puffing (25 mL/s), puff-associated respiration (450 mL/s), and tidal inhalation (350 mL/s). The maximum flowrate observed in the fabricated BAES was 450 mL/s, exceeding the lower target nominal wall shear stress of 0.025 Pa upstream of the bifurcation and fell below the target of 0.02 Pa downstream. This in vitro system addresses several gaps observed in commercially available systems and may be used to study many inhaled aerosols. The current work illustrates how in silico models may be used to correlate results of an in vitro study to in vivo conditions, rather than attempting to design an in vitro system that performs exactly as the human respiratory tract.
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Affiliation(s)
- S. Emma Sarles
- Department of Mechanical Engineering, Rochester Institute of Technology, 77 Lomb Memorial Drive, Rochester, NY 14623
| | - Edward C. Hensel
- Department of Mechanical Engineering, Rochester Institute of Technology, 77 Lomb Memorial Drive, Rochester, NY 14623
| | - Janessa Terry
- Department of Mechanical Engineering, Rochester Institute of Technology, 77 Lomb Memorial Drive, Rochester, NY 14623
| | - Caleb Nuss
- Department of Mechanical Engineering, Rochester Institute of Technology, 77 Lomb Memorial Drive, Rochester, NY 14623
| | - Risa J. Robinson
- Department of Mechanical Engineering, Rochester Institute of Technology, 77 Lomb Memorial Drive, Rochester, NY 14623
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3
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Manna VJ, Dwyer S, Pizutelli V, Caradonna SJ. Utilizing primary human airway mucociliary tissue cultures to model ramifications of chronic E-cigarette usage. Toxicol In Vitro 2024; 94:105725. [PMID: 37884163 DOI: 10.1016/j.tiv.2023.105725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 09/27/2023] [Accepted: 10/22/2023] [Indexed: 10/28/2023]
Abstract
Electronic cigarettes are battery powered devices that use a vape-liquid to produce a vapor that is inhaled. A consequence of the rise in e-cigarette usage was the 2019 emergence of a vaping-induced respiratory disease denoted as 'e-cigarette or vaping use-associated lung injury' (EVALI). One of the suspected causes of EVALI is Vitamin E Acetate (VEA), which was found to be a diluent in certain illicit vape-pens, whereas nicotine is commonly diluted in equal parts propylene glycol and vegetable glycerin (PG:VG). The prevalent use of e-cigarettes and the emergence of a novel illness has made understanding how e-cigarette vapors affect our respiratory tissues a public health concern. We have designed and produced a simple device that can operate e-cigarettes and deliver the vapor to a chamber containing a standard cell culture multi-well plate. Here we utilize our device to model the response of human airway mucociliary tissue after chronic exposure to vapors produced from either PG:VG or VEA. We note several differences between how PG:VG and VEA vapors interact with and alter airway tissue cultures and suggest potential mechanisms for how VEA-vapors can exacerbate EVALI symptoms. Our device combined with primary human airway tissue cultures make an economical and compact model system that allows for animal-free investigations into the acute and chronic consequences of e-cigarette vapors on primary respiratory cells.
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Affiliation(s)
- Vincent J Manna
- Department of Molecular Biology, Graduate School of Biomedical Sciences and School of Osteopathic Medicine, Rowan University, Stratford, NJ, United States.
| | - Shannon Dwyer
- Department of Molecular Biology, Graduate School of Biomedical Sciences and School of Osteopathic Medicine, Rowan University, Stratford, NJ, United States
| | - Vanessa Pizutelli
- Department of Molecular Biology, Graduate School of Biomedical Sciences and School of Osteopathic Medicine, Rowan University, Stratford, NJ, United States
| | - Salvatore J Caradonna
- Department of Molecular Biology, Graduate School of Biomedical Sciences and School of Osteopathic Medicine, Rowan University, Stratford, NJ, United States
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Shipman JG, Onyenwoke RU, Sivaraman V. Vaping-Dependent Pulmonary Inflammation Is Ca 2+ Mediated and Potentially Sex Specific. Int J Mol Sci 2024; 25:1785. [PMID: 38339063 PMCID: PMC10855597 DOI: 10.3390/ijms25031785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/12/2024] Open
Abstract
Here we use the SCIREQ InExpose system to simulate a biologically relevant vaping model in mice to investigate the role of calcium signaling in vape-dependent pulmonary disease as well as to investigate if there is a gender-based difference of disease. Male and female mice were vaped with JUUL Menthol (3% nicotine) using the SCIREQ InExpose system for 2 weeks. Additionally, 2-APB, a known calcium signaling inhibitor, was administered as a prophylactic for lung disease and damage caused by vaping. After 2 weeks, mice were exposed to lipopolysaccharide (LPS) to mimic a bacterial infection. Post-infection (24 h), mice were sacrificed, and bronchoalveolar lavage fluid (BALF) and lungs were taken. Vaping primed the lungs for worsened disease burden after microbial challenge (LPS) for both males and females, though females presented increased neutrophilia and inflammatory cytokines post-vape compared to males, which was assessed by flow cytometry, and cytokine and histopathological analysis. This increased inflammatory burden was controlled by calcium signaling inhibition, suggesting that calcium dysregulation may play a role in lung injury caused by vaping in a gender-dependent manner.
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Affiliation(s)
- Jeffrey G. Shipman
- Department of Biological & Biomedical Sciences, North Carolina Central University, Durham, NC 27707, USA; (J.G.S.); (R.U.O.)
| | - Rob U. Onyenwoke
- Department of Biological & Biomedical Sciences, North Carolina Central University, Durham, NC 27707, USA; (J.G.S.); (R.U.O.)
- Biomanufacturing Research Institute and Technology Enterprise (BRITE), North Carolina Central University, Durham, NC 27707, USA
| | - Vijay Sivaraman
- Department of Biological & Biomedical Sciences, North Carolina Central University, Durham, NC 27707, USA; (J.G.S.); (R.U.O.)
- The Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, NC 27707, USA
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Wang H, Lu F, Tian Y, Zhang S, Han S, Fu Y, Li J, Feng P, Shi Z, Chen H, Hou H. Evaluation of toxicity of heated tobacco products aerosol and cigarette smoke to BEAS-2B cells based on 3D biomimetic chip model. Toxicol In Vitro 2024; 94:105708. [PMID: 37806364 DOI: 10.1016/j.tiv.2023.105708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/28/2023] [Accepted: 10/03/2023] [Indexed: 10/10/2023]
Abstract
It is still a controversial topic about evaluating whether heated tobacco products (HTP) really reduce harm, which involves the choice of an experimental model. Here, a three-dimensional (3D) biomimetic chip model was used to evaluate the toxicity of aerosols came from HTP and smoke produced by cigarettes (Cig). Based on cell-related experiments, we found that the toxicity of Cig smoke extract diluted four times was also much higher than that of undiluted HTP, showing higher oxidative stress response and cause mitochondrial dysfunction. Meanwhile, both tobacco products all affect the tricarboxylic acid cycle (TCA), which is manifested by a significant decrease in the mRNA expression of TCA key rate-limiting enzymes. Summarily, 3D Biomimetic chip technology can be used as an ideal model to evaluate HTP. It can provide important data for tobacco risk assessment when 3D chip model was used. Our experimental results showed that HTP may be less harmful than tobacco cigarettes, but it does show significant cytotoxicity with the increase of dose. Therefore, the potential clinical effects of HTP on targeted organs such as lung should be further studied.
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Affiliation(s)
- Hongjuan Wang
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China; Beijing Institute of Life Science and Technology, Beijing, China; Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, China
| | - Fengjun Lu
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China
| | - Yushan Tian
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China; Beijing Institute of Life Science and Technology, Beijing, China; Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, China
| | - Sen Zhang
- Shaanxi Key Laboratory of Degradable Biomedical Materials, School of Chemical Engineering, Northwest University, Xi'an 710069, China
| | - Shulei Han
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China; Beijing Institute of Life Science and Technology, Beijing, China; Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, China
| | - Yaning Fu
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China; Beijing Institute of Life Science and Technology, Beijing, China; Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, China
| | - Jun Li
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China; Beijing Institute of Life Science and Technology, Beijing, China; Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, China
| | - Pengxia Feng
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China
| | - Zhihao Shi
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China
| | - Huan Chen
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China; Beijing Institute of Life Science and Technology, Beijing, China; Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, China.
| | - Hongwei Hou
- China National Tobacco Quality Supervision &Test Center, Zhengzhou, China; Key Laboratory of Tobacco Biological Effects, Zhengzhou, China; Beijing Institute of Life Science and Technology, Beijing, China; Key Labortory of Tobacco Biological Effects and Biosynthesis, Beijing, China.
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Pinkston R, Penn AL, Noël A. Increased oxidative stress responses in murine macrophages exposed at the air-liquid interface to third- and fourth-generation electronic nicotine delivery system (ENDS) aerosols. Toxicol Rep 2023; 11:40-57. [PMID: 37405056 PMCID: PMC10315815 DOI: 10.1016/j.toxrep.2023.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 06/06/2023] [Accepted: 06/14/2023] [Indexed: 07/06/2023] Open
Abstract
Background New fourth generation electronic nicotine delivery system (ENDS) devices contain high levels of nicotine salt (up to 60 mg/mL), whose cellular and molecular effects on immune cells are currently unknown. Here, we used a physiologically-relevant in vitro air-liquid interface (ALI) exposure model to assess the toxicity of distinct ENDS, a 3rd-generation electronic-cigarette (e-cig) and two 4th-generation ENDS devices (JUUL and Posh Plus). Methods Murine macrophages (RAW 264.7) were exposed at the ALI to either air, Menthol or Crème Brûlée-flavored ENDS aerosols generated from those devices for 1-hour per day for 1 or 3 consecutive days. Cellular and molecular toxicity was evaluated 24 h post-exposure. Results 1-day of Menthol-flavored JUUL aerosol exposure significantly decreased cell viability and significantly increased lactate dehydrogenase (LDH) levels compared to air controls. Further, JUUL Menthol elicited significantly increased reactive oxygen species (ROS) and nitric oxide (NO) production compared to air controls. Posh Crème Brûlée-flavored aerosols displayed significant cytotoxicity - decreased cell viability and increased LDH levels -after 1- and 3-day exposures, while the Crème Brûlée-flavored aerosol produced by the 3rd-generation e-cig device only displayed significant cytotoxicity after 3 days compared to air controls. Further, both Posh and third-generation e-cig Crème Brûlée flavored-aerosols elicited significantly increased ROS plus high levels of 8-isoprostane after 1 and 3 days compared to air controls, indicating increased oxidative stress. Posh and third-generation e-cig Crème Brûlée flavored-aerosols elicited reduction in NO levels after one day, but elicited increase in NO after 3 days. Genes in common dysregulated by both devices after 1 day included α7nAChR, Cyp1a1, Ahr, Mmp12, and iNos. Conclusion Our results suggest that ENDS Menthol and Crème Brûlée-flavored aerosol exposures from both 3rd- and 4th-generation ENDS devices are cytotoxic to macrophages and cause oxidative stress. This can translate into macrophage dysfunction. Although 4th-generation disposable ENDS devices have no adjustable operational settings and are considered low-powered ENDS devices, their aerosols can induce cellular toxicity compared to air-exposed control cells. This study provides scientific evidence for regulation of nicotine salt-based disposable ENDS products.
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Affiliation(s)
- Rakeysha Pinkston
- Department of Environmental Toxicology, Southern University and A & M College, Baton Rouge, LA 70813, USA
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, 1909 Skip Bertman Drive, Baton Rouge, LA 70803, USA
| | - Arthur L Penn
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, 1909 Skip Bertman Drive, Baton Rouge, LA 70803, USA
| | - Alexandra Noël
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, 1909 Skip Bertman Drive, Baton Rouge, LA 70803, USA
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Sachdeva J, Karunananthan A, Shi J, Dai W, Kleinman MT, Herman D, Kloner RA. Flavoring Agents in E-cigarette Liquids: A Comprehensive Analysis of Multiple Health Risks. Cureus 2023; 15:e48995. [PMID: 38111420 PMCID: PMC10726647 DOI: 10.7759/cureus.48995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/15/2023] [Indexed: 12/20/2023] Open
Abstract
The availability of a wide range of flavored e-cigarettes is one of the primary reasons for vaping initiation and persistent use among adolescents and young people. This plethora of flavors available on the market are crafted using different flavoring agents such as cinnamaldehyde, vanillin, benzaldehyde, ethyl maltol, menthol, and dimethylpyrazine. Recent studies have brought to light the potential risks associated with e-cigarette flavoring agents and their effects on various organ systems, both with and without nicotine. Research has demonstrated that flavoring agents can induce inflammation, endothelial dysfunction, epithelial barrier disruption, oxidative stress, DNA damage, electrophysiological alterations, immunomodulatory effects, and behavioral changes, even independently of nicotine. Notably, these negative outcomes adversely affect cardiovascular system by reducing cell viability, decreasing endothelial nitric oxide synthase, nitric oxide bioavailability, soluble guanylyl cyclase activity and cyclic guanosine monophosphate accumulation, impairing endothelial proliferation and tube formation, and altering vasoreactivity resulting in vascular dysfunction. In the heart, these agents decrease parasympathetic activity, induce depolarization of resting membrane potential, loss of rhythmicity, increase isovolumic relaxation time, and change in ventricular repolarization and ventricular tachyarrhythmias. It is found that the specific response elicited by flavoring agents in different organ systems varies depending on the flavor used, the concentration of the flavoring agent, and the duration of exposure. However, the literature on the effects of flavoring agents is currently limited, emphasizing the need for more preclinical and randomized clinical trials to gain a deeper understanding and provide further evidence of the harmful effects of flavored e-cigarette use. In summary, recent research suggests that flavoring agents themselves can have detrimental effects on the body. To fully comprehend these effects, additional preclinical and clinical studies are needed to explore the risks associated with flavored e-cigarette usage.
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Affiliation(s)
- Jaspreet Sachdeva
- Cardiovascular Sciences, Huntington Medical Research Institutes, Pasadena, USA
| | | | - Jianru Shi
- Cardiovascular Sciences, Huntington Medical Research Institutes, Pasadena, USA
| | - Wangde Dai
- Cardiovascular Sciences, Huntington Medical Research Institutes, Pasadena, USA
| | - Michael T Kleinman
- Environmental and Occupational Health, College of Health Sciences, University of California, Irvine, USA
| | - David Herman
- Environmental and Occupational Health, College of Health Sciences, University of California, Irvine, USA
| | - Robert A Kloner
- Cardiovascular Sciences, Huntington Medical Research Institutes, Pasadena, USA
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Been T, Alakhtar B, Traboulsi H, Tsering T, Bartolomucci A, Heimbach N, Paoli S, Burnier J, Mann KK, Eidelman DH, Baglole CJ. Chronic low-level JUUL aerosol exposure causes pulmonary immunologic, transcriptomic, and proteomic changes. FASEB J 2023; 37:e22732. [PMID: 36694994 DOI: 10.1096/fj.202201392r] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 11/18/2022] [Accepted: 12/14/2022] [Indexed: 01/26/2023]
Abstract
E-cigarettes currently divide public opinion, with some considering them a useful tool for smoking cessation and while others are concerned with potentially adverse health consequences. However, it may take decades to fully understand the effects of e-cigarette use in humans given their relative newness on the market. This highlights the need for comprehensive preclinical studies investigating the effects of e-cigarette exposure on health outcomes. Here, we investigated the impact of chronic, low-level JUUL aerosol exposure on multiple lung outcomes. JUUL is a brand of e-cigarettes popular with youth and young adults. To replicate human exposures, 8- to 12-week-old male and female C57BL/6J mice were exposed to commercially available JUUL products (containing 59 mg/ml nicotine). Mice were exposed to room air, PG/VG, or JUUL daily for 4 weeks. After the exposure period, inflammatory markers were assessed via qRT-PCR, multiplex cytokine assays, and differential cell count. Proteomic and transcriptomic analyses were also performed on samples isolated from the lavage of the lungs; this included unbiased analysis of proteins contained within extracellular vesicles (EVs). Mice exposed to JUUL aerosols for 4 weeks had significantly increased neutrophil and lymphocyte populations in the BAL and some changes in cytokine mRNA expression. However, BAL cytokines did not change. Proteomic and transcriptomic analysis revealed significant changes in numerous biological pathways including neutrophil degranulation, PPAR signaling, and xenobiotic metabolism. Thus, e-cigarettes are not inert and can cause significant cellular and molecular changes in the lungs.
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Affiliation(s)
- Terek Been
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada.,Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Bayan Alakhtar
- Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
| | - Hussein Traboulsi
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Thupten Tsering
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Pathology, McGill University, Montreal, Quebec, Canada
| | - Alexandra Bartolomucci
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Pathology, McGill University, Montreal, Quebec, Canada
| | - Nicole Heimbach
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada.,Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Sofia Paoli
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada.,Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Julia Burnier
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Pathology, McGill University, Montreal, Quebec, Canada
| | - Koren K Mann
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada.,Department of Oncology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
| | - David H Eidelman
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Carolyn J Baglole
- Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada.,Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada.,Department of Pathology, McGill University, Montreal, Quebec, Canada.,Department of Medicine, McGill University, Montreal, Quebec, Canada
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Noël A, Ghosh A. Carbonyl Profiles of Electronic Nicotine Delivery System (ENDS) Aerosols Reflect Both the Chemical Composition and the Numbers of E-Liquid Ingredients-Focus on the In Vitro Toxicity of Strawberry and Vanilla Flavors. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:16774. [PMID: 36554655 PMCID: PMC9779252 DOI: 10.3390/ijerph192416774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/11/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Propylene glycol (PG) and glycerin (G) are the most widely used humectants in electronic nicotine delivery system (ENDS) devices. Carbonyls are present in aerosols produced when ENDS devices heat PG and G. Whether aerosolized PG and G are innocuous to the lungs has not been established. Here, we determined the chemical profiles of ENDS aerosols containing three humectant ratios (30/70, 50/50 and 70/30, PG/VG), for three flavors (strawberry, vanilla and Catalan cream) containing either 12 or 18 mg/mL of nicotine. Additionally, we examined the in vitro toxicity of the strawberry- and vanilla-flavored ENDS aerosol in human lung epithelial cells (BEAS-2B) exposed at the air-liquid interface for 1 h. For strawberry- and vanilla-flavored aerosols produced by a 3rd-generation ENDS device with the same PG/G ratio, the e-liquid nicotine content of 12 and 18 mg/mL did not transfer to the aerosol with substantial differences in concentrations. Our data also indicate the presence of carbonyls in all three flavored e-cig aerosols analyzed, with levels exceeding 1 µg/puff for acetone, butyraldehyde, and acetaldehyde, in strawberry-, vanilla, and Catalan cream-flavored e-cig aerosols, respectively. Furthermore, closed-system ENDS of the fourth generation emitted trace levels of carbonyls in the aerosols (<0.3 µg/puff), while open-system tank-style ENDS of the third generation produced elevated levels of harmful chemicals, including acrolein (>1 µg/puff), formaldehyde (>5 µg/puff), and m- & p-tolualdehyde (>4 µg/puff). Moreover, under non-cytotoxic conditions, BEAS-2B cells exposed to strawberry-flavored aerosols exhibited significantly increased reactive oxygen and nitric oxide species (ROS/NOS) levels in cell media compared to air controls, while vanilla-flavored ENDS aerosols up-regulated the expression of pro-inflammatory and oxidative stress markers. Our data suggest (a) that ENDS aerosol chemical composition will vary based upon the presence and concentration of the initial e-liquid ingredients, with a pronounced impact of the flavoring components; and (b) short-term exposures to flavored ENDS aerosols may impair lung cells' redox signaling in a flavor-specific manner.
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Effah F, Taiwo B, Baines D, Bailey A, Marczylo T. Pulmonary effects of e-liquid flavors: a systematic review. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2022; 25:343-371. [PMID: 36154615 PMCID: PMC9590402 DOI: 10.1080/10937404.2022.2124563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Electronic cigarettes (ECs) are purported to be tobacco harm-reduction products whose degree of harm has been highly debated. EC use is considered less hazardous than smoking but is not expected to be harmless. Following the banning of e-liquid flavors in countries such as the US, Finland, Ukraine, and Hungary, there are growing concerns regarding the safety profile of e-liquid flavors used in ECs. While these are employed extensively in the food industry and are generally regarded as safe (GRAS) when ingested, GRAS status after inhalation is unclear. The aim of this review was to assess evidence from 38 reports on the adverse effects of flavored e-liquids on the respiratory system in both in vitro and in vivo studies published between 2006 and 2021. Data collected demonstrated greater detrimental effects in vitro with cinnamon (9 articles), strawberry (5 articles), and menthol (10 articles), flavors than other flavors. The most reported effects among these investigations were perturbations of pro-inflammatory biomarkers and enhanced cytotoxicity. There is sufficient evidence to support the toxicological impacts of diacetyl- and cinnamaldehyde-containing e-liquids following human inhalation; however, safety profiles on other flavors are elusive. The latter may result from inconsistencies between experimental approaches and uncertainties due to the contributions from other e-liquid constituents. Further, the relevance of the concentration ranges to human exposure levels is uncertain. Evidence indicates that an adequately controlled and consistent, systematic toxicological investigation of a broad spectrum of e-liquid flavors may be required at biologically relevant concentrations to better inform public health authorities on the risk assessment following exposure to EC flavor ingredients.
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Affiliation(s)
- Felix Effah
- Pharmacology Section, St George’s University of London, London, UK
- Radiation, Chemical and Environmental Hazards, UK Health Security Agency, Didcot, UK
| | - Benjamin Taiwo
- Physiology Section, St George’s University of London, London, UK
| | - Deborah Baines
- Infection and Immunity Institute, St George’s University of London, London, UK
| | - Alexis Bailey
- Pharmacology Section, St George’s University of London, London, UK
| | - Tim Marczylo
- Radiation, Chemical and Environmental Hazards, UK Health Security Agency, Didcot, UK
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11
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Wong ET, Luettich K, Cammack L, Chua CS, Sciuscio D, Merg C, Corciulo M, Piault R, Ashutosh K, Smith C, Leroy P, Moine F, Glabasnia A, Diana P, Chia C, Tung CK, Ivanov N, Hoeng J, Peitsch M, Lee KM, Vanscheeuwijck P. Assessment of inhalation toxicity of cigarette smoke and aerosols from flavor mixtures: 5-week study in A/J mice. J Appl Toxicol 2022; 42:1701-1722. [PMID: 35543240 PMCID: PMC9545811 DOI: 10.1002/jat.4338] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/20/2022] [Accepted: 05/05/2022] [Indexed: 11/10/2022]
Abstract
Most flavors used in e-liquids are generally recognized as safe for oral consumption, but their potential effects when inhaled are not well characterized. In vivo inhalation studies of flavor ingredients in e-liquids are scarce. A structure-based grouping approach was used to select 38 flavor group representatives (FGR) on the basis of known and in silico-predicted toxicological data. These FGRs were combined to create prototype e-liquid formulations and tested against cigarette smoke (CS) in a 5-week inhalation study. Female A/J mice were whole-body exposed for 6 h/day, 5 days/week, for 5 weeks to air, mainstream CS, or aerosols from (1) test formulations containing propylene glycol (PG), vegetable glycerol (VG), nicotine (N; 2% w/w), and flavor (F) mixtures at low (4.6% w/w), medium (9.3% w/w), or high (18.6% w/w) concentration or (2) base formulation (PG/VG/N). Male A/J mice were exposed to air, PG/VG/N, or PG/VG/N/F-high under the same exposure regimen. There were no significant mortality or in-life clinical findings in the treatment groups, with only transient weight loss during the early exposure adaptation period. While exposure to flavor aerosols did not cause notable lung inflammation, it caused only minimal adaptive changes in the larynx and nasal epithelia. In contrast, exposure to CS resulted in lung inflammation and moderate-to-severe changes in the epithelia of the nose, larynx, and trachea. In summary, the study evaluates an approach for assessing the inhalation toxicity potential of flavor mixtures, thereby informing the selection of flavor exposure concentrations (up to 18.6%) for a future chronic inhalation study.
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Affiliation(s)
- Ee Tsin Wong
- PMI R&DPhilip Morris International Research Laboratories Pte LtdSingapore
| | | | - Lydia Cammack
- PMI R&DPhilip Morris International Research Laboratories Pte LtdSingapore
| | - Chin Suan Chua
- PMI R&DPhilip Morris International Research Laboratories Pte LtdSingapore
| | | | - Celine Merg
- PMI R&DPhilip Morris Products S.ANeuchâtelSwitzerland
| | | | - Romain Piault
- PMI R&DPhilip Morris Products S.ANeuchâtelSwitzerland
| | | | | | - Patrice Leroy
- PMI R&DPhilip Morris Products S.ANeuchâtelSwitzerland
| | - Fabian Moine
- PMI R&DPhilip Morris Products S.ANeuchâtelSwitzerland
| | | | | | - Cecilia Chia
- PMI R&DPhilip Morris International Research Laboratories Pte LtdSingapore
| | - Ching Keong Tung
- PMI R&DPhilip Morris International Research Laboratories Pte LtdSingapore
| | | | - Julia Hoeng
- PMI R&DPhilip Morris Products S.ANeuchâtelSwitzerland
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12
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Been T, Traboulsi H, Paoli S, Alakhtar B, Mann KK, Eidelman DH, Baglole CJ. Differential impact of JUUL flavors on pulmonary immune modulation and oxidative stress responses in male and female mice. Arch Toxicol 2022; 96:1783-1798. [PMID: 35254488 DOI: 10.1007/s00204-022-03269-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/23/2022] [Indexed: 12/17/2022]
Abstract
JUUL is a popular e-cigarette brand that manufactures e-liquids in a variety of flavors, such as mango and mint. Despite their popularity, the pulmonary effects of flavored JUUL e-liquids that are aerosolized and subsequently inhaled are not known. Therefore, the purpose of this study was to evaluate if acute exposure to JUUL e-cigarette aerosols in three popular flavors elicits an immunomodulatory or oxidative stress response in mice. We first developed a preclinical model that mimics human use patterns of e-cigarettes using 1 puff/min or 4 puffs/min exposure regimes. Based on cotinine levels, these exposures were representative of light/occasional and moderate JUUL users. We then exposed C57BL/6 mice to JUUL e-cigarette aerosols in mango, mint, and Virginia tobacco flavors containing 5% nicotine for 3 days, and assessed the inflammatory and oxidative stress response in the lungs and blood. In response to the 1 puff/min regime (light/occasional user), there were minimal changes in BAL cell composition or lung mRNA expression. However, at 4 puffs/min (moderate user), mint-flavored JUUL significantly increased lung neutrophils, while mango-flavored JUUL significantly increased Tnfα and Il13 mRNA in the lungs. Both the 1- and 4 puffs/min regimes significantly increased oxidative stress markers in the blood, indicating systemic effects. Thus, JUUL products are not inert; even short-term inhalation of flavored JUUL e-cigarette aerosols differentially causes immune modulation and oxidative stress responses.
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Affiliation(s)
- Terek Been
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada.,Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Hussein Traboulsi
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,Department of Medicine, McGill University, Montreal, QC, Canada
| | - Sofia Paoli
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada.,Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Bayan Alakhtar
- Division of Experimental Medicine, McGill University, Montreal, QC, Canada
| | - Koren K Mann
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada.,Department of Oncology, Lady Davis Institute for Medical Research, McGill University, Montreal, QC, Canada
| | - David H Eidelman
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,Department of Medicine, McGill University, Montreal, QC, Canada
| | - Carolyn J Baglole
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada. .,Research Institute of the McGill University Health Centre, Montreal, QC, Canada. .,Department of Medicine, McGill University, Montreal, QC, Canada. .,Department of Pathology, McGill University, Montreal, QC, Canada.
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13
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Wong CY, Ong HX, Traini D. The application of in vitro cellular assays for analysis of electronic cigarettes impact on the airway. Life Sci 2022; 298:120487. [DOI: 10.1016/j.lfs.2022.120487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/01/2022] [Accepted: 03/14/2022] [Indexed: 10/18/2022]
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14
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Zhang W, Lin H, Zou M, Yuan Q, Huang Z, Pan X, Zhang W. Nicotine in Inflammatory Diseases: Anti-Inflammatory and Pro-Inflammatory Effects. Front Immunol 2022; 13:826889. [PMID: 35251010 PMCID: PMC8895249 DOI: 10.3389/fimmu.2022.826889] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/21/2022] [Indexed: 11/13/2022] Open
Abstract
As an anti-inflammatory alkaloid, nicotine plays dual roles in treating diseases. Here we reviewed the anti-inflammatory and pro-inflammatory effects of nicotine on inflammatory diseases, including inflammatory bowel disease, arthritis, multiple sclerosis, sepsis, endotoxemia, myocarditis, oral/skin/muscle inflammation, etc., mainly concerning the administration methods, different models, therapeutic concentration and duration, and relevant organs and tissues. According to the data analysis from recent studies in the past 20 years, nicotine exerts much more anti-inflammatory effects than pro-inflammatory ones, especially in ulcerative colitis, arthritis, sepsis, and endotoxemia. On the other hand, in oral inflammation, nicotine promotes and aggravates some diseases such as periodontitis and gingivitis, especially when there are harmful microorganisms in the oral cavity. We also carefully analyzed the nicotine dosage to determine its safe and effective range. Furthermore, we summarized the molecular mechanism of nicotine in these inflammatory diseases through regulating immune cells, immune factors, and the vagus and acetylcholinergic anti-inflammatory pathways. By balancing the “beneficial” and “harmful” effects of nicotine, it is meaningful to explore the effective medical value of nicotine and open up new horizons for remedying acute and chronic inflammation in humans.
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Affiliation(s)
- Wenji Zhang
- Guangdong Provincial Engineering & Technology Research Center for Tobacco Breeding and Comprehensive Utilization, Key Laboratory of Crop Genetic Improvement of Guangdong Province, Crops Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Hui Lin
- Department of Radiation Oncology, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Mingmin Zou
- Guangdong Provincial Engineering & Technology Research Center for Tobacco Breeding and Comprehensive Utilization, Key Laboratory of Crop Genetic Improvement of Guangdong Province, Crops Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Qinghua Yuan
- Guangdong Provincial Engineering & Technology Research Center for Tobacco Breeding and Comprehensive Utilization, Key Laboratory of Crop Genetic Improvement of Guangdong Province, Crops Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Zhenrui Huang
- Guangdong Provincial Engineering & Technology Research Center for Tobacco Breeding and Comprehensive Utilization, Key Laboratory of Crop Genetic Improvement of Guangdong Province, Crops Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Xiaoying Pan
- Guangdong Provincial Engineering & Technology Research Center for Tobacco Breeding and Comprehensive Utilization, Key Laboratory of Crop Genetic Improvement of Guangdong Province, Crops Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- *Correspondence: Xiaoying Pan, ; Wenjuan Zhang,
| | - Wenjuan Zhang
- Department of Public Health and Preventive Medicine, School of Medicine, Jinan University, Guangzhou, China
- *Correspondence: Xiaoying Pan, ; Wenjuan Zhang,
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15
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Goenka S, Simon SR. Effects of E-Cigarette Refill Liquid Flavorings with and without Nicotine on Human Retinal Pigment Epithelial Cells: A Preliminary Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182111655. [PMID: 34770169 PMCID: PMC8582700 DOI: 10.3390/ijerph182111655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/30/2021] [Accepted: 11/03/2021] [Indexed: 02/07/2023]
Abstract
Smoking is an etiologic factor for age-related macular degeneration (AMD). Although cigarette smoke has been extensively researched for retinal pigment epithelial (RPE) cell degeneration, the potential for adverse effects on the retinal epithelium following exposure to flavored e-cigarette refill liquid has never been explored. In this preliminary study, we have examined the effects of 20 e-liquids (10 different flavored nicotine-free and 10 nicotine-rich e-liquids) used in e-cigarettes on the metabolic activity, membrane integrity, and mitochondrial membrane potential of RPE cells. Our results showed that of the flavors studied over the concentration range: 0.5, 1, and 2% v/v for a duration of 48 h, cinnamon was the most toxic and menthol was the second most toxic, while other flavors showed lesser or no cytotoxicity. The presence of nicotine augmented cytotoxicity for cinnamon, menthol, strawberry, vanilla, and banana while for other flavors there was no synergism. Together, our results demonstrate that exposure of RPE to flavored e-cigarette refill liquids caused significant cytotoxicity and may be a risk factor for the development of retinal pathogenesis, although further in-depth studies are necessary.
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Affiliation(s)
- Shilpi Goenka
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-5281, USA;
- Department of Biochemistry and Cellular Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
- Correspondence:
| | - Sanford R. Simon
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-5281, USA;
- Department of Biochemistry and Cellular Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
- Department of Pathology, Stony Brook University, Stony Brook, NY 11794, USA
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16
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Shipman JG, Onyenwoke RU, Sivaraman V. Calcium-Dependent Pulmonary Inflammation and Pharmacological Interventions and Mediators. BIOLOGY 2021; 10:1053. [PMID: 34681152 PMCID: PMC8533358 DOI: 10.3390/biology10101053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 12/17/2022]
Abstract
Pulmonary diseases present a significant burden worldwide and lead to severe morbidity and mortality. Lung inflammation caused by interactions with either viruses, bacteria or fungi is a prominent characteristic of many pulmonary diseases. Tobacco smoke and E-cig use ("vaping") are considered major risk factors in the development of pulmonary disease as well as worsening disease prognosis. However, at present, relatively little is known about the mechanistic actions by which smoking and vaping may worsen the disease. One theory suggests that long-term vaping leads to Ca2+ signaling dysregulation. Ca2+ is an important secondary messenger in signal transduction. Cellular Ca2+ concentrations are mediated by a complex series of pumps, channels, transporters and exchangers that are responsible for triggering various intracellular processes such as cell death, proliferation and secretion. In this review, we provide a detailed understating of the complex series of components that mediate Ca2+ signaling and how their dysfunction may result in pulmonary disease. Furthermore, we summarize the recent literature investigating the negative effects of smoking and vaping on pulmonary disease, cell toxicity and Ca2+ signaling. Finally, we summarize Ca2+-mediated pharmacological interventions that could potentially lead to novel treatments for pulmonary diseases.
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Affiliation(s)
- Jeffrey G. Shipman
- Department of Biological and Biomedical Sciences, College of Health and Sciences, North Carolina Central University, Durham, NC 27707, USA;
| | - Rob U. Onyenwoke
- Department of Pharmaceutical Sciences, North Carolina Central University, Durham, NC 27707, USA;
- Biomanufacturing Research Institute and Technology Enterprise (BRITE), North Carolina Central University, Durham, NC 27707, USA
| | - Vijay Sivaraman
- Department of Biological and Biomedical Sciences, College of Health and Sciences, North Carolina Central University, Durham, NC 27707, USA;
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17
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Bennet TJ, Randhawa A, Hua J, Cheung KC. Airway-On-A-Chip: Designs and Applications for Lung Repair and Disease. Cells 2021; 10:1602. [PMID: 34206722 PMCID: PMC8304815 DOI: 10.3390/cells10071602] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/21/2021] [Accepted: 06/23/2021] [Indexed: 12/22/2022] Open
Abstract
The lungs are affected by illnesses including asthma, chronic obstructive pulmonary disease, and infections such as influenza and SARS-CoV-2. Physiologically relevant models for respiratory conditions will be essential for new drug development. The composition and structure of the lung extracellular matrix (ECM) plays a major role in the function of the lung tissue and cells. Lung-on-chip models have been developed to address some of the limitations of current two-dimensional in vitro models. In this review, we describe various ECM substitutes utilized for modeling the respiratory system. We explore the application of lung-on-chip models to the study of cigarette smoke and electronic cigarette vapor. We discuss the challenges and opportunities related to model characterization with an emphasis on in situ characterization methods, both established and emerging. We discuss how further advancements in the field, through the incorporation of interstitial cells and ECM, have the potential to provide an effective tool for interrogating lung biology and disease, especially the mechanisms that involve the interstitial elements.
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Affiliation(s)
- Tanya J. Bennet
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (T.J.B.); (A.R.); (J.H.)
- Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Avineet Randhawa
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (T.J.B.); (A.R.); (J.H.)
- Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jessica Hua
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (T.J.B.); (A.R.); (J.H.)
- Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Karen C. Cheung
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; (T.J.B.); (A.R.); (J.H.)
- Centre for Blood Research, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Department of Electrical & Computer Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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18
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Da Silva E, Vogel U, Hougaard KS, Pérez-Gil J, Zuo YY, Sørli JB. An adverse outcome pathway for lung surfactant function inhibition leading to decreased lung function. Curr Res Toxicol 2021; 2:225-236. [PMID: 34345865 PMCID: PMC8320609 DOI: 10.1016/j.crtox.2021.05.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/19/2021] [Accepted: 05/25/2021] [Indexed: 12/27/2022] Open
Abstract
Inhaled substances, such as consumer products, chemicals at the workplace, and nanoparticles, can affect the lung function in several ways. In this paper, we explore the adverse outcome pathway (AOP) that starts when inhaled substances that reach the alveoli inhibit the function of the lung surfactant, and leads to decreased lung function. Lung surfactant covers the inner surface of the alveoli, and regulates the surface tension at the air-liquid interface during breathing. The inhibition of the lung surfactant function leads to alveolar collapse because of the resulting high surface tension at the end of expiration. The collapsed alveoli can be re-opened by inspiration, but this re-opening causes shear stress on cells covering the alveoli. This can damage the alveolar-capillary membrane integrity, allowing blood components to enter the alveolar airspace. Blood components, such as albumin, can interact with the lung surfactant and further inhibit its function. The collapse of the alveoli is responsible for a decrease in the surface area available for blood oxygenation, and it reduces the volume of air that can be inhaled and exhaled. These different key events lead to decreased lung function, characterized by clinical signs of respiratory toxicity and reduced blood oxygenation. Here we present the weight of evidence that supports the AOP, and we give an overview of the methods available in vitro and in vivo to measure each key event of the pathway, and how this AOP can potentially be used in screening for inhalation toxicity.
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Key Words
- AO, adverse outcome
- AOP, adverse outcome pathway
- ARDS, acute respiratory distress syndrome
- Adverse outcome pathway
- Alternative method
- EAGMST, Extended Advisory Group on Molecular Screening and Toxicogenomics
- GHS, Globally Harmonized System of Classification and Labelling of Chemicals
- Inhalation
- KE, key event
- Lung surfactant
- MIE, molecular initiating event
- Nanomaterials
- New approach methodology
- OECD, Organisation for Economic Cooperation and Development
- OI, oxygenation index
- PaO2, dissolved oxygen in the plasma
- SaO2, percentage of hemoglobin saturated with oxygen
- Spray products
- TEER, trans epithelial electrical resistance
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Affiliation(s)
- Emilie Da Silva
- National Research Centre for the Working Environment, Copenhagen, Denmark
- DTU Environment, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ulla Vogel
- National Research Centre for the Working Environment, Copenhagen, Denmark
- DTU Health Tech, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Karin S. Hougaard
- National Research Centre for the Working Environment, Copenhagen, Denmark
- Department of Public Health, University of Copenhagen, Denmark
| | - Jesus Pérez-Gil
- Faculty of Biology and Research Institute “12 de Octubre (imas12)”, Complutense University, Madrid, Spain
| | - Yi Y. Zuo
- Department of Mechanical Engineering, University of Hawaii at Manoa, Honolulu, HI, United States
| | - Jorid B. Sørli
- National Research Centre for the Working Environment, Copenhagen, Denmark
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19
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Toxicology of flavoring- and cannabis-containing e-liquids used in electronic delivery systems. Pharmacol Ther 2021; 224:107838. [PMID: 33746051 DOI: 10.1016/j.pharmthera.2021.107838] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/11/2021] [Indexed: 12/15/2022]
Abstract
Electronic cigarettes (e-cigarettes) were introduced in the United States in 2007 and by 2014 they were the most popular tobacco product amongst youth and had overtaken use of regular tobacco cigarettes. E-cigarettes are used to aerosolize a liquid (e-liquid) that the user inhales. Flavorings in e-liquids is a primary reason for youth to initiate use of e-cigarettes. Evidence is growing in the scientific literature that inhalation of some flavorings is not without risk of harm. In this review, 67 original articles (primarily cellular in vitro) on the toxicity of flavored e-liquids were identified in the PubMed and Scopus databases and evaluated critically. At least 65 individual flavoring ingredients in e-liquids or aerosols from e-cigarettes induced toxicity in the respiratory tract, cardiovascular and circulatory systems, skeletal system, and skin. Cinnamaldehyde was most frequently reported to be cytotoxic, followed by vanillin, menthol, ethyl maltol, ethyl vanillin, benzaldehyde and linalool. Additionally, modern e-cigarettes can be modified to aerosolize cannabis as dried plant material or a concentrated extract. The U.S. experienced an outbreak of lung injuries, termed e-cigarette, or vaping, product use-associated lung injury (EVALI) that began in 2019; among 2,022 hospitalized patients who had data on substance use (as of January 14, 2020), 82% reported using a delta-9-tetrahydrocannabinol (main psychoactive component in cannabis) containing e-cigarette, or vaping, product. Our literature search identified 33 articles related to EVALI. Vitamin E acetate, a diluent and thickening agent in cannabis-based products, was strongly linked to the EVALI outbreak in epidemiologic and laboratory studies; however, e-liquid chemistry is highly complex, and more than one mechanism of lung injury, ingredient, or thermal breakdown product may be responsible for toxicity. More research is needed, particularly with regard to e-cigarettes (generation, power settings, etc.), e-liquids (composition, bulk or vaped form), modeled systems (cell type, culture type, and dosimetry metrics), biological monitoring, secondhand exposures and contact with residues that contain nicotine and flavorings, and causative agents and mechanisms of EVALI toxicity.
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20
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Singh DP, Begum R, Kaur G, Bagam P, Kambiranda D, Singh R, Batra S. E-cig vapor condensate alters proteome and lipid profiles of membrane rafts: impact on inflammatory responses in A549 cells. Cell Biol Toxicol 2021; 37:773-793. [PMID: 33469865 DOI: 10.1007/s10565-020-09573-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 11/12/2020] [Indexed: 01/14/2023]
Abstract
Electronic cigarettes (e-cigs) are battery-operated heating devices that aerosolize e-liquid, typically containing nicotine and several other chemicals, which is then inhaled by a user. Over the past decade, e-cigs have gained immense popularity among both smokers and non-smokers. One reason for this is that they are advertised as a safe alternative to conventional cigarettes. However, the recent reports of e-cig use associated lung injury have ignited a considerable debate about the relative harm and benefits of e-cigs. The number of reports about e-cig-induced inflammation and pulmonary health is increasing as researchers seek to better understand the effects of vaping on human health. In line with this, we investigated the molecular events responsible for the e-cig vapor condensate (ECVC)-mediated inflammation in human lung adenocarcinoma type II epithelial cells (A549). In an attempt to limit the variables caused by longer ingredient lists of flavored e-cigs, tobacco-flavored ECVC (TF-ECVC±nicotine) was employed for this study. Interestingly, we observed significant upregulation of cytokines and chemokines (IL-6, IL-8, and MCP-1) in A549 cells following a 48 h TF-ECVC challenge. Furthermore, there was a significant increase in the expression of pattern recognition receptors TLR-4 and NOD-1, lipid raft-associated protein caveolin-1, and transcription factor NF-кB in TF-ECVC with and/or without nicotine-challenged lung epithelial cells. Our results further demonstrate the harboring of TLR-4 and NOD-1 in the caveolae of TF-ECVC-challenged A549 cells. Proteomic and lipidomic analyses of lipid raft fractions from control and challenged cells revealed a distinct protein and lipid profile in TF-ECVC (w/wo nicotine)-exposed A549 cells. Interestingly, the inflammatory effects of TF-ECVC (w/wo nicotine) were inhibited following the caveolin-1 knockdown, thus demonstrating a critical role of caveolae raft-mediated signaling in eliciting inflammatory responses upon TF-ECVC challenge. Graphical Abstract Graphical Abstract.
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Affiliation(s)
- Dhirendra Pratap Singh
- Laboratory of Pulmonary Immunotoxicology, Department of Environmental Toxicology, 129 Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Rizwana Begum
- Laboratory of Pulmonary Immunotoxicology, Department of Environmental Toxicology, 129 Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Gagandeep Kaur
- Laboratory of Pulmonary Immunotoxicology, Department of Environmental Toxicology, 129 Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Prathyusha Bagam
- Laboratory of Pulmonary Immunotoxicology, Department of Environmental Toxicology, 129 Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Devaiah Kambiranda
- Southern University Agriculture Research and Extension Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Rakesh Singh
- Translational Science Laboratory, FSU College of Medicine, Tallahassee, FL, 32309, USA
| | - Sanjay Batra
- Laboratory of Pulmonary Immunotoxicology, Department of Environmental Toxicology, 129 Health Research Center, Southern University and A&M College, Baton Rouge, LA, 70813, USA.
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Kaur G, Gaurav A, Lamb T, Perkins M, Muthumalage T, Rahman I. Current Perspectives on Characteristics, Compositions, and Toxicological Effects of E-Cigarettes Containing Tobacco and Menthol/Mint Flavors. Front Physiol 2020; 11:613948. [PMID: 33329065 PMCID: PMC7710937 DOI: 10.3389/fphys.2020.613948] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 10/23/2020] [Indexed: 11/13/2022] Open
Abstract
Electronic nicotine delivery systems/devices (ENDS) such as electronic cigarettes (e-cigarettes) have been made available globally, with the intent to reduce tobacco smoking. To make these products more appealing to young adults, many brands have added flavoring agents. However, these flavoring agents are shown to progressively result in lung toxicity when inhaled via e-cigarettes. While recent federal regulations have banned the sale of flavored e-cigarettes other than tobacco or menthol flavors, concerns have been raised about the health effects of even these flavors. In this review, we evaluate the current toxicological data with regard to effects upon exposure in animal models and in vitro cell culture for these popular flavorants. We have tabulated the current e-cigarette products containing these most common flavors (menthol, mint, and tobacco) in the market. We have also indicated the prevalence of tobacco and menthol-flavor use among e-cigarette users and highlighted the possible challenges and benefits that will result from new federal regulations.
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Affiliation(s)
- Gurjot Kaur
- School of Pharmaceutical Sciences, Shoolini University, Solan, India
| | - Anshuman Gaurav
- School of Pharmaceutical Sciences, Shoolini University, Solan, India
| | - Thomas Lamb
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States
| | - Melanie Perkins
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States
| | - Thivanka Muthumalage
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States
| | - Irfan Rahman
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, United States
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22
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Vermehren MF, Wiesmann N, Deschner J, Brieger J, Al-Nawas B, Kämmerer PW. Comparative analysis of the impact of e-cigarette vapor and cigarette smoke on human gingival fibroblasts. Toxicol In Vitro 2020; 69:105005. [PMID: 32956835 DOI: 10.1016/j.tiv.2020.105005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/01/2020] [Accepted: 09/16/2020] [Indexed: 11/21/2022]
Abstract
Human gingival fibroblasts (HGF) play a vital role in wound healing, oral cancer, and are among the first cells being exposed to e-cigarette vapor (eCV) or cigarette smoke (CS) during inhalation. Although the cell-damaging effect of CS has been well studied, the effects of eCV on gingival cells are still unclear. The aim of this in vitro study was to compare the effects of eCV and CS on HGF in terms of proliferation, metabolic activity, cell death, and formation of reactive oxygen species (ROS). After 24 h cell numbers in CS-exposed cells in contrast to eCV-exposed cells were significantly decreased compared to the control. At later points in time, such differences could no longer be observed. Compared to the control, HGF stimulated with eCV showed a significantly higher metabolic activity 1 h, 24 h, and 48 h after exposure. 24 h after exposure, the metabolic activity was increased in both test groups. No caspase 3/7 activation nor significant differences in the amount of apoptosis/necrosis among the groups were seen. Only in CS-exposed cells ROS formation was increased at 1 h, 3 h, and 6 h after exposition. In conclusion, when compared to conventional CS, a less harmful effect of eCV on HGF can be assumed.
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Affiliation(s)
- M F Vermehren
- Department of Oral and Maxillofacial Surgery, Plastic Surgery, University Medical Centre Mainz, Augustusplatz 2, 55131 Mainz, Germany
| | - N Wiesmann
- Department of Oral and Maxillofacial Surgery, Plastic Surgery, University Medical Centre Mainz, Augustusplatz 2, 55131 Mainz, Germany; Department of Otorhinolaryngology, University Medical Centre Mainz, Langenbeckstr. 1, 55131 Mainz, Germany.
| | - J Deschner
- Department of Periodontology and Operative Dentistry, University Medical Centre Mainz, Augustusplatz 2, 55131 Mainz, Germany
| | - J Brieger
- Department of Otorhinolaryngology, University Medical Centre Mainz, Langenbeckstr. 1, 55131 Mainz, Germany
| | - B Al-Nawas
- Department of Oral and Maxillofacial Surgery, Plastic Surgery, University Medical Centre Mainz, Augustusplatz 2, 55131 Mainz, Germany
| | - P W Kämmerer
- Department of Oral and Maxillofacial Surgery, Plastic Surgery, University Medical Centre Mainz, Augustusplatz 2, 55131 Mainz, Germany
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23
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Smart DJ, Phillips G. Collecting e-cigarette aerosols for in vitro applications: A survey of the biomedical literature and opportunities to increase the value of submerged cell culture-based assessments. J Appl Toxicol 2020; 41:161-174. [PMID: 33015847 PMCID: PMC7756347 DOI: 10.1002/jat.4064] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/11/2020] [Accepted: 08/18/2020] [Indexed: 12/11/2022]
Abstract
Electronic nicotine delivery systems (ENDS) are being developed as potentially reduced‐risk alternatives to the continued use of combustible tobacco products. Because of the widespread uptake of ENDS—in particular, e‐cigarettes—the biological effects, including the toxic potential, of their aerosols are under investigation. Preclinically, collection of such aerosols is a prerequisite for testing in submerged cell culture‐based in vitro assays; however, despite the growth in this research area, there is no apparent standardized collection method for this application. To this end, through an Institute for in vitro Sciences, Inc. workshop initiative, we surveyed the biomedical literature catalogued in PubMed® to map the types of methods hitherto used and reported publicly. From the 47 relevant publications retrieved, we identified seven distinct collection methods. Bubble‐through (with aqueous solvents) and Cambridge filter pad (CFP) (with polar solvents) collection were the most frequently cited methods (57% and 18%, respectively), while the five others (CFP + bubble‐through; condensation; cotton filters; settle‐upon; settle‐upon + dry) were cited less often (2–10%). Critically, the collected aerosol fractions were generally found to be only minimally characterized chemically, if at all. Furthermore, there was large heterogeneity among other experimental parameters (e.g., vaping regimen). Consequently, we recommend that more comprehensive research be conducted to identify the method(s) that produce the fraction(s) most representative of the native aerosol. We also endorse standardization of the aerosol generation process. These should be regarded as opportunities for increasing the value of in vitro assessments in relation to predicting effects on human health. Collection of e‐cigarette aerosols is a prerequisite to enable testing in submerged culture‐based in vitro assays; however, there is no standardized method for this. Thus, we surveyed the biomedical literature to map the types of published methods. Bubble‐through and Cambridge filter pad methods were most common, although there was heterogeneity among other parameters, and moreover, the resulting fractions were only minimally characterized. Comprehensive research is required to identify the method(s) that produce the fraction(s) most representative of the native aerosol.
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Affiliation(s)
- Daniel J Smart
- PMI R&D, Philip Morris Products SA, Neuchâtel, Switzerland
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24
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Barrameda R, Nguyen T, Wong V, Castro G, Rodriguez de la Vega P, Lozano J, Zevallos J. Use of E-Cigarettes and Self-Reported Lung Disease Among US Adults. Public Health Rep 2020; 135:785-795. [PMID: 32972319 DOI: 10.1177/0033354920951140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVES Initially marketed for smoking cessation, electronic cigarettes (e-cigarettes) are commonly regarded as safer than combustible cigarettes because they usually contain less nicotine and do not use combustion. However, few studies have examined the health effects of e-cigarettes. The objective of this study was to examine whether e-cigarette use had a differential effect on the prevalence of lung disease among current, former, and never tobacco users. METHODS We analyzed data from respondents aged ≥18 (n = 45 908) who responded to questions about e-cigarette use and lung disease in the 2016 Behavioral Risk Factor Surveillance System (BRFSS) survey. We calculated crude odd ratios (ORs) and ORs adjusted by 15 sociodemographic and health behavior factors: age, sex, race/ethnicity, annual household income, health insurance, personal physician, health status, body mass index, education, marital status, exercise, alcohol use, tobacco smoking, tobacco chewing, and metropolitan status. RESULTS We found a significant association between e-cigarette use and lung disease, which was significantly modified by tobacco use. Among never tobacco users, the adjusted odds of reporting lung disease were 4.36 (95% CI, 1.76-10.77) times higher among everyday e-cigarette users than among never e-cigarette users. Among current tobacco users, the adjusted odds of reporting lung disease were 1.47 (95% CI, 1.13-1.92) times higher among everyday e-cigarette users than among never e-cigarette users. CONCLUSIONS People who have never smoked combustible cigarettes should refrain from starting e-cigarettes, because e-cigarettes carry a significant risk of lung disease independent of tobacco smoking. Additional prospective research into the harmful effects of e-cigarettes would help to further elucidate this link.
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Affiliation(s)
- Robelyn Barrameda
- 158263 Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
| | - Trisha Nguyen
- 158263 Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
| | - Vivian Wong
- 158263 Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
| | - Grettel Castro
- 158263 Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
| | | | - Juan Lozano
- 158263 Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
| | - Juan Zevallos
- 158263 Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
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25
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Rao DR, Maple KL, Dettori A, Afolabi F, Francis JK, Artunduaga M, Lieu TJ, Aldy K, Cao DJ, Hsu S, Feng SY, Mittal V. Clinical Features of E-cigarette, or Vaping, Product Use-Associated Lung Injury in Teenagers. Pediatrics 2020; 146:peds.2019-4104. [PMID: 32393606 PMCID: PMC7961805 DOI: 10.1542/peds.2019-4104] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/06/2020] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND In the United States in 2019, there was an outbreak of electronic cigarette, or vaping, product use-associated lung injury (EVALI). The manifestations of EVALI in adolescents are not well characterized. We describe the diagnosis, evaluation, and management of EVALI in adolescents hospitalized at a tertiary care, university-affiliated children's hospital. METHODS A multidisciplinary committee developed an EVALI algorithm on the basis of guidelines from the Centers for Disease Control and Prevention. A retrospective chart review was conducted on patients diagnosed with EVALI. Descriptive analyses included sociodemographic characteristics, clinical presentation, laboratory and imaging results, pulmonary function testing, oxygen requirements, and clinic follow-up. RESULTS Thirteen hospitalized adolescents were diagnosed with confirmed or probable EVALI. The majority were female (54%) with a mean age of 15.9 years. Sixty-nine percent of patients presented with respiratory symptoms, whereas gastrointestinal symptoms were prominent in 85% of patients. Vaping Δ-9-tetrahydrocannabinol was reported in 92% of patients, and vaping nicotine was reported in 62% of patients. All had bilateral ground-glass opacities on the chest computed tomography (CT) scan. Treatment with glucocorticoids led to clinical improvement in 11 of 12 patients. Treatment with glucocorticoids led to improvement in both forced expiratory volume in 1 second and forced vital capacity (P < .05). Four patients required home oxygen on the basis of 6-minute walk test results. CONCLUSIONS Diagnosis of EVALI should be suspected on the basis of vaping history and clinical presentation. Glucocorticoid treatment led to an improvement in symptoms and lung function. The 6-minute walk test may help determine oxygen needs at discharge.
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Affiliation(s)
- Devika R. Rao
- Division of Respiratory Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,Children’s Health Medical Center Dallas, Dallas, Texas
| | - Kendra L. Maple
- Medical School, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Amy Dettori
- Division of Respiratory Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,Children’s Health Medical Center Dallas, Dallas, Texas
| | - Folashade Afolabi
- Division of Respiratory Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,Children’s Health Medical Center Dallas, Dallas, Texas
| | - Jenny K.R. Francis
- Division of Developmental-Behavioral Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,Children’s Health Medical Center Dallas, Dallas, Texas
| | - Maddy Artunduaga
- Division of Pediatric Radiology, Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas;,Children’s Health Medical Center Dallas, Dallas, Texas
| | - Tiffany J. Lieu
- Division of Pediatric Hospital Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Kim Aldy
- Division of Medical Toxicology, Department of Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,North Texas Poison Center, Parkland Health and Hospital System, Dallas, Texas
| | - Dazhe James Cao
- Division of Medical Toxicology, Department of Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,North Texas Poison Center, Parkland Health and Hospital System, Dallas, Texas
| | - Stephanie Hsu
- Division of Critical Care Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,Children’s Health Medical Center Dallas, Dallas, Texas
| | - Sing Yi Feng
- Division of Emergency Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,North Texas Poison Center, Parkland Health and Hospital System, Dallas, Texas
| | - Vineeta Mittal
- Division of Pediatric Hospital Medicine, University of Texas Southwestern Medical Center, Dallas, Texas;,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas;,Children’s Health Medical Center Dallas, Dallas, Texas
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26
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Al-Saleh I, Elkhatib R, Al-Rajoudi T, Al-Qudaihi G, Manogarannogaran P, Eltabache C, Alotaibi A, Mummer AB, Almugbel S. Cytotoxic and genotoxic effects of e-liquids and their potential associations with nicotine, menthol and phthalate esters. CHEMOSPHERE 2020; 249:126153. [PMID: 32058129 DOI: 10.1016/j.chemosphere.2020.126153] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/15/2020] [Accepted: 02/06/2020] [Indexed: 05/06/2023]
Abstract
In this study, we determined DNA damage and chromosome breakage (indicators of genotoxicity) and cell viability (an indicator of cytotoxicity) in human lymphoblastoid TK6 and Chinese hamster ovary (CHO) cells treated with 33 e-liquids using in vitro single cell gel (comet), micronucleus (MN), and trypan blue assays, respectively. We also measured the contents of nicotine, five phthalate esters, and DL-menthol in the e-liquids to examine their effects on DNA damage, chromosome breakage, and cell viability. Our chemical analyses showed that: (1) six e-liquids had nicotine ≥2-fold higher than the manufacture's label claim (2-3.5 mg); (2) both dimethyl- and dibutyl-phthalate levels were >0.1 μg/g, i.e., their threshold limits as additives in cosmetics; and (3) the DL-menthol contents ranged from 0.0003 to 85757.2 μg/g, with those of two e-liquids being >1 mg/g, the threshold limit for trigging sensory irritation. Though all the e-liquids induced DNA damage in TK6 cells, 20 resulted in cell viabilities ≤75%, indicating cytotoxicity, yet the inverse relationship between cell viability and DNA damage (r = -0.628, p = 0.003) might reflect their role as pro-apoptotic and DNA damage inducers. Fifteen e-liquids induced MN% in TK6 cells ≥3-fold that of untreated cells. Some of the increase in %MN might be false due to high cytotoxicity, yet six brands showed acceptable cell viabilities (59-71%), indicating chromosome damage. DNA damage and %MN increased when the TK6 cells were exposed to metabolic activation. The CHO cells were less sensitive to the genotoxic effects of the e-liquids than the TK6 cells. DL-menthol was found to be associated with decreased cell viability and increased DNA damage, even at low levels. We cannot dismiss the presence of other ingredients in e-liquids with cytotoxic/genotoxic properties since out of the 63 different flavors, 47 induced DNA damage (≥3-folds), and 26 reduced cell viability (≤75%) in TK6 cells.
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Affiliation(s)
| | | | | | | | | | | | - Aminah Alotaibi
- National Center for Biotechnology and Genomic Research, King Abdulaziz City for Science and Technology, Saudi Arabia
| | - Abdulrahman Bin Mummer
- Biostatistics, Epidemiology & Scientific Computing Department, King Faisal Specialist Hospital & Research Centre, Saudi Arabia
| | - Saad Almugbel
- College of Medicine, Al-Imam Muhammed Ibn Saud Islamic University, Riyadh, Saudi Arabia
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27
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Traboulsi H, Cherian M, Abou Rjeili M, Preteroti M, Bourbeau J, Smith BM, Eidelman DH, Baglole CJ. Inhalation Toxicology of Vaping Products and Implications for Pulmonary Health. Int J Mol Sci 2020; 21:E3495. [PMID: 32429092 PMCID: PMC7278963 DOI: 10.3390/ijms21103495] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/28/2020] [Accepted: 05/12/2020] [Indexed: 12/17/2022] Open
Abstract
E-cigarettes have a liquid that may contain flavors, solvents, and nicotine. Heating this liquid generates an aerosol that is inhaled into the lungs in a process commonly referred to as vaping. E-cigarette devices can also contain cannabis-based products including tetrahydrocannabinol (THC), the psychoactive component of cannabis (marijuana). E-cigarette use has rapidly increased among current and former smokers as well as youth who have never smoked. The long-term health effects are unknown, and emerging preclinical and clinical studies suggest that e-cigarettes may not be harmless and can cause cellular alterations analogous to traditional tobacco smoke. Here, we review the historical context and the components of e-cigarettes and discuss toxicological similarities and differences between cigarette smoke and e-cigarette aerosol, with specific reference to adverse respiratory outcomes. Finally, we outline possible clinical disorders associated with vaping on pulmonary health and the recent escalation of acute lung injuries, which led to the declaration of the vaping product use-associated lung injury (EVALI) outbreak. It is clear there is much about vaping that is not understood. Consequently, until more is known about the health effects of vaping, individual factors that need to be taken into consideration include age, current and prior use of combustible tobacco products, and whether the user has preexisting lung conditions such as asthma and chronic obstructive pulmonary disease (COPD).
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Affiliation(s)
- Hussein Traboulsi
- Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (H.T.); (M.A.R.); (M.P.); (J.B.); (B.M.S.)
| | - Mathew Cherian
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada; (M.C.); (D.H.E.)
| | - Mira Abou Rjeili
- Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (H.T.); (M.A.R.); (M.P.); (J.B.); (B.M.S.)
- Respiratory Epidemiology and Clinical Research Unit, McGill University Health Centre, Montreal, QC H4A 3J1, Canada
| | - Matthew Preteroti
- Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (H.T.); (M.A.R.); (M.P.); (J.B.); (B.M.S.)
- Department of Pathology, McGill University, Montreal, QC H3A 2B4, Canada
| | - Jean Bourbeau
- Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (H.T.); (M.A.R.); (M.P.); (J.B.); (B.M.S.)
- Respiratory Epidemiology and Clinical Research Unit, McGill University Health Centre, Montreal, QC H4A 3J1, Canada
| | - Benjamin M. Smith
- Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (H.T.); (M.A.R.); (M.P.); (J.B.); (B.M.S.)
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada; (M.C.); (D.H.E.)
- Respiratory Epidemiology and Clinical Research Unit, McGill University Health Centre, Montreal, QC H4A 3J1, Canada
| | - David H. Eidelman
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada; (M.C.); (D.H.E.)
| | - Carolyn J. Baglole
- Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (H.T.); (M.A.R.); (M.P.); (J.B.); (B.M.S.)
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada; (M.C.); (D.H.E.)
- Department of Pathology, McGill University, Montreal, QC H3A 2B4, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC H3G 1Y6, Canada
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28
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Nemmar A, Al-Salam S, Beegam S, Yuvaraju P, Zaaba NE, Yasin J, Ali BH. Waterpipe Tobacco Smoke Inhalation Triggers Thrombogenicity, Cardiac Inflammation and Oxidative Stress in Mice: Effects of Flavouring. Int J Mol Sci 2020; 21:E1291. [PMID: 32075078 PMCID: PMC7072969 DOI: 10.3390/ijms21041291] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 12/29/2019] [Accepted: 01/02/2020] [Indexed: 12/26/2022] Open
Abstract
The consumption of water-pipe smoking (WPS) has been promoted by the use of flavoured tobacco. However, little is known about the impact of flavouring on the cardiovascular toxicity induced by WPS inhalation. Here, we compared the cardiovascular effects and underlying mechanism of actions of plain (P) (unflavoured) versus apple-flavoured (AF) WPS (30 minutes/day, 5 days/week for 1 month) in mice. Control mice were exposed to air. Both P- and AF-WPS inhalation induced an increase in systolic blood pressure, thrombogenicity and plasma concentration of fibrinogen and von Willebrand factor. In heart homogenates, AF-WPS inhalation caused an increase of 8-isoprostane and a decrease in the levels of reduced glutathione (GSH) and superoxide dismutase (SOD). Nevertheless, P-WPS decreased only the activity of SOD. The concentrations of tumour necrosis factor α and interleukin 1β were increased only in heart homogenates of mice exposed to AF-WPS. Although both P- and AF-WPS increased the concentration of troponin I in heart homogenates and induced DNA damage, the concentration of cleaved caspase 3 was only increased in mice exposed to AF-WPS. Immunohistochemical analysis of the hearts showed that both P- and AF- WPS inhalation decreased the expression of SOD. Moreover, the expression of nuclear factor erythroid-derived 2-like 2 at nuclear level in the heart was higher in both AF-WPS and P-WPS compared with control group, and the effect observed in AF-WPS group was more significant than that seen in P-WPS group. Likewise, the concentration of heme oxygenase-1 was significantly increased in both P-WPS and AF-WPS groups compared with control group, and the effect seen in AF-group was higher than that observed in P-WPS group. In conclusion, our findings showed that both P- and AF-WPS induce thrombogenicity and cardiac injury, and that this toxicity is potentiated by the presence of flavouring.
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Affiliation(s)
- Abderrahim Nemmar
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666 Al Ain, UAE; (S.B.); (P.Y.); (N.E.Z.)
- Zayed Center for Health Sciences, United Arab Emirates University, P.O. Box 17666 Al Ain, UAE
| | - Suhail Al-Salam
- Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666 Al Ain, UAE;
| | - Sumaya Beegam
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666 Al Ain, UAE; (S.B.); (P.Y.); (N.E.Z.)
| | - Priya Yuvaraju
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666 Al Ain, UAE; (S.B.); (P.Y.); (N.E.Z.)
| | - Nur Elena Zaaba
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666 Al Ain, UAE; (S.B.); (P.Y.); (N.E.Z.)
| | - Javed Yasin
- Department of Internal Medicine, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666 Al Ain, UAE;
| | - Badreldin H. Ali
- Department of Pharmacology and Clinical Pharmacy, College of Medicine & Health Sciences, Sultan Qaboos University, P.O. Box 35, Muscat 123, Al-Khod, Oman;
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29
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Go YY, Mun JY, Chae SW, Chang J, Song JJ. Comparison between in vitro toxicities of tobacco- and menthol-flavored electronic cigarette liquids on human middle ear epithelial cells. Sci Rep 2020; 10:2544. [PMID: 32054887 PMCID: PMC7018737 DOI: 10.1038/s41598-020-59290-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 01/17/2020] [Indexed: 12/20/2022] Open
Abstract
Since electronic-cigarettes (e-cigarettes) are considered less toxic than conventional tobacco smoking, the use of e-cigarettes has increased, and the market for e-cigarette liquids (e-liquids) is continuously increasing. However, many studies showed that e-cigarettes may cause various harmful effects in lung, oral and heart. In this study, we investigated the effects of e-liquids on otitis media (OM) using human middle ear epithelial cells (HMEECs). Menthol-flavored e-liquid induced significant cell death in HMEECs (IC50: 1.45 ± 0.14%) and tobacco-flavored e-liquid led to increase in inflammatory cytokine levels and higher mucin production. Flavored e-liquids decreased the mRNA levels of genes encoding epithelial sodium channels (ENaCs) in HMEECs. Apoptosis and autophagy reactions were induced by exposure of HMEECs to menthol- and tobacco-flavored e-liquids. Tobacco-flavored e-liquids caused a greater increase in the levels of autophagosome marker, LC3-II, compared to menthol-flavored e-liquids, which was followed by cell death. These results demonstrate that flavored e-liquids cause cytotoxicity via apoptosis, autophagy, inflammatory response, and mucin production in HMEECs. The flavors present in e-liquids might be a risk factor for the development of otitis media.
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Affiliation(s)
- Yoon Young Go
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Ji Yoen Mun
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Sung-Won Chae
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea
| | - Jiwon Chang
- Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University College of Medicine, Seoul, Korea.
| | - Jae-Jun Song
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
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30
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Gómez AC, Rodríguez-Fernández P, Villar-Hernández R, Gibert I, Muriel-Moreno B, Lacoma A, Prat-Aymerich C, Domínguez J. E-cigarettes: Effects in phagocytosis and cytokines response against Mycobacterium tuberculosis. PLoS One 2020; 15:e0228919. [PMID: 32040536 PMCID: PMC7010305 DOI: 10.1371/journal.pone.0228919] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 01/22/2020] [Indexed: 01/17/2023] Open
Abstract
Cigarette smoking and tuberculosis are a significant cause of death worldwide. Several epidemiological studies have demonstrated cigarette smoking is a risk factor for tuberculosis. Electronic cigarettes have recently appeared as a healthier alternative to conventional smoking, although their impact in tuberculosis is not well understood. The aim of this study was to explore the effect of electronic cigarettes in phagocytosis of Mycobacterium tuberculosis and cytokines production. In vitro infection was carried out by exposing THP-1 macrophages to four electronic vapor extracts and the intracellular burden of M. tuberculosis was determined. The percentage of infection was evaluated by confocal microscopy and the cytokine production by Luminex. A reduction of intracellular M. tuberculosis burden in THP-1 macrophages was found after its exposure to electronic vapor extract; the same trend was observed by confocal microscopy when Mycobacterium bovis BCG-GFP strain was used. Electronic cigarettes stimulate a pro-inflammatory cytokine response. We conclude that electronic cigarettes impair the phagocytic function and the cytokine response to M. tuberculosis.
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Affiliation(s)
- Andromeda-Celeste Gómez
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Badalona, Catalonia, Spain
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB), Bellaterra (Cerdanyola del Vallès), Barcelona, Catalonia, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Barcelona, Catalonia, Spain
| | - Pablo Rodríguez-Fernández
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Badalona, Catalonia, Spain
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB), Bellaterra (Cerdanyola del Vallès), Barcelona, Catalonia, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Barcelona, Catalonia, Spain
| | - Raquel Villar-Hernández
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Badalona, Catalonia, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Barcelona, Catalonia, Spain
| | - Isidre Gibert
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB), Bellaterra (Cerdanyola del Vallès), Barcelona, Catalonia, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Barcelona, Catalonia, Spain
| | - Beatriz Muriel-Moreno
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Badalona, Catalonia, Spain
| | - Alicia Lacoma
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Badalona, Catalonia, Spain
| | - Cristina Prat-Aymerich
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Badalona, Catalonia, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Barcelona, Catalonia, Spain
| | - Jose Domínguez
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Badalona, Catalonia, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Barcelona, Catalonia, Spain
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Short-term E-cigarette toxicity effects on brain cognitive memory functions and inflammatory responses in mice. Toxicol Res 2020; 36:267-273. [PMID: 32685431 DOI: 10.1007/s43188-019-00031-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 11/05/2019] [Accepted: 12/06/2019] [Indexed: 12/18/2022] Open
Abstract
Exposure to cigarette smoke (CS) is associated with an increased risk of several neurological diseases such as stroke, Alzheimer's disease, and dementia. At present, commercialization of E-cigarettes (ECs) is increasing, and they are advertised as a less harmful nicotine-delivery system. There are, however, limited studies regarding the neurotoxicity effects of ECs on the brain, which remains a subject of debate. In the present study, we aimed to evaluate the in vivo effects of short-term EC vapor exposure on the brain and compare them with the effects of cigarette smoke (CS). BALB/c mice were exposed to air, CS, and EC for 14 days. We then assessed the inflammatory responses, oxidative stress, and cognitive functions of the mice by using maze tests. Cognitive spatial tests showed that the mice exposed to CS and ECs had delayed time in finding food rewards. EC exposure demonstrated no improvement in spatial memory learning to find the food reward on the next day. This implies that CS and EC exposure possibly causes damage to the olfactory system. Notably, EC exposure potentially causes abnormalities in mice memory functions. Histological staining of the cerebral cortex of mice brain in the EC-exposed group demonstrated inflammatory responses such as necrosis and cytoplasm vacuolization. Immunohistochemical staining revealed high expression of proinflammatory cytokine TNF-α in both the EC- and CS-exposed groups. Hence, we conclude that ECs share similar toxicity profiles as CS, which potentially negatively impact brain function.
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Bozier J, Chivers EK, Chapman DG, Larcombe AN, Bastian NA, Masso-Silva JA, Byun MK, McDonald CF, Crotty Alexander LE, Ween MP. The Evolving Landscape of e-Cigarettes: A Systematic Review of Recent Evidence. Chest 2020; 157:1362-1390. [PMID: 32006591 DOI: 10.1016/j.chest.2019.12.042] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 12/15/2019] [Accepted: 12/16/2019] [Indexed: 01/12/2023] Open
Abstract
Smoking continues to be a burden to economies and health-care systems across the world. One proposed solution to the problem has been e-cigarettes; however, because they are a relatively new product in the market, little is known about their potential health impacts. Furthermore, e-cigarettes continue to evolve at a rapid rate, making it necessary to regularly review and summarize available studies. Although e-cigarettes are marketed as a smoking cessation tool by some manufacturers, the reality is that many nonsmokers, including youth, are using them. This review focuses on two major demographic groups (smokers and nonsmokers) and evaluates the most recent data (early 2017 to mid 2019) regarding the potential health effects of e-cigarettes. We assessed peer-reviewed studies on the health impacts of e-cigarettes, with a particular focus on common questions asked by policy makers, clinicians, and scientists: (1) What are the effects of e-cigarettes compared with air/not smoking?; (2) Is there any direct evidence of harm or benefit to humans?; (3) Is there a risk from secondhand exposure?; (4) What are the risks and/or benefits of e-cigarettes compared with tobacco cigarette use?; (5) Are there risks or benefits to specific populations (eg, people with COPD or asthma, pregnant women [and their offspring])?; (6) What are the effects of flavoring chemicals?; (7) What are the effects of including nicotine in e-liquids?; (8) How often is nicotine concentration labeling incorrect?; and (9) What are the risks when e-cigarettes explode?
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Affiliation(s)
- Jack Bozier
- School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia; Woolcock Institute of Medical Research, University of Sydney, Sydney, NSW, Australia
| | | | - David G Chapman
- School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia; Woolcock Institute of Medical Research, University of Sydney, Sydney, NSW, Australia
| | - Alexander N Larcombe
- Telethon Kids Institute, Perth, WA, Australia; School of Public Health, Curtin University, Perth, WA, Australia
| | - Nicole A Bastian
- Discipline of Obstetrics and Gynaecology, School of Medicine, Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - Jorge A Masso-Silva
- Department of Medicine, Division of Pulmonary Critical Care & Sleep, University of California San Diego, San Diego, CA
| | - Min Kwang Byun
- Department of Medicine, Division of Pulmonary Critical Care & Sleep, University of California San Diego, San Diego, CA; Division of Pulmonology, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
| | - Christine F McDonald
- Department of Respiratory and Sleep Medicine, Austin Health, Heidelberg, VIC, Australia; Institute for Breathing and Sleep, Heidelberg, VIC, Australia; School of Medicine, University of Melbourne, VIC, Australia
| | - Laura E Crotty Alexander
- Department of Medicine, Division of Pulmonary Critical Care & Sleep, University of California San Diego, San Diego, CA; Pulmonary Critical Care Section, Veterans Affairs San Diego Healthcare System, San Diego, CA
| | - Miranda P Ween
- School of Medicine, University of Adelaide, Adelaide, SA, Australia; Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia.
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Merecz-Sadowska A, Sitarek P, Zielinska-Blizniewska H, Malinowska K, Zajdel K, Zakonnik L, Zajdel R. A Summary of In Vitro and In Vivo Studies Evaluating the Impact of E-Cigarette Exposure on Living Organisms and the Environment. Int J Mol Sci 2020; 21:ijms21020652. [PMID: 31963832 PMCID: PMC7013895 DOI: 10.3390/ijms21020652] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/03/2020] [Accepted: 01/15/2020] [Indexed: 12/11/2022] Open
Abstract
Worldwide use of electronic cigarettes has been rapidly expanding over recent years, but the long-term effect of e-cigarette vapor exposure on human health and environment is not well established; however, its mechanism of action entails the production of reactive oxygen species and trace metals, and the exacerbation of inflammation, which are associated with potential cytotoxicity and genotoxicity. The present study examines the effects of selected liquid chemicals used in e-cigarettes, such as propylene glycol/vegetable glycerin, nicotine and flavorings, on living organisms; the data collected indicates that exposure to e-cigarette liquid has potentially detrimental effects on cells in vitro, and on animals and humans in vivo. While e-liquid exposure can adversely influence the physiology of living organisms, vaping is recommended as an alternative for tobacco smoking. The study also compares the impact of e-cigarette liquid exposure and traditional cigarette smoke on organisms and the environmental impact. The environmental influence of e-cigarette use is closely connected with the emission of airborne particulate matter, suggesting the possibility of passive smoking. The obtained data provides an insight into the impact of nicotine delivery systems on living organisms and the environment.
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Affiliation(s)
- Anna Merecz-Sadowska
- Department of Economic Informatics, University of Lodz, 90-214 Lodz, Poland; (K.M.); (L.Z.); (R.Z.)
- Correspondence: ; Tel.: +48-663-626-667
| | - Przemyslaw Sitarek
- Department of Biology and Pharmaceutical Botany, Medical University of Lodz, 90-151 Lodz, Poland;
| | | | - Katarzyna Malinowska
- Department of Economic Informatics, University of Lodz, 90-214 Lodz, Poland; (K.M.); (L.Z.); (R.Z.)
- Department of Allergology and Respiratory Rehabilitation, Medical University of Lodz, 90-725 Lodz, Poland;
| | - Karolina Zajdel
- Department of Medical Informatics and Statistics, Medical University of Lodz, 90-645 Lodz, Poland;
| | - Lukasz Zakonnik
- Department of Economic Informatics, University of Lodz, 90-214 Lodz, Poland; (K.M.); (L.Z.); (R.Z.)
| | - Radoslaw Zajdel
- Department of Economic Informatics, University of Lodz, 90-214 Lodz, Poland; (K.M.); (L.Z.); (R.Z.)
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34
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Krishnan-Sarin S, O’Malley SS. The science of flavour in tobacco products. WORLD HEALTH ORGANIZATION TECHNICAL REPORT SERIES 2019; 1015:125-142. [PMID: 36743396 PMCID: PMC9896977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Abstract
Sale of electronic cigarette (e-cigarette) products has exponentially increased in the past decade, which raise concerns about its safety. This updated review provides the available toxicology profile of e-cigarettes, summarizing evidence from in vitro and in vivo studies. Data regarding which components in e-liquids exhibit potential toxicities are inconsistent. Some studies have reported that nicotine plays a significant role in inducing adverse outcomes and that solvents alone do not induce any adverse effects. However, other studies have suggested that nicotine is not associated with any adverse outcomes, whereas solvents and flavorings are the key components to elicit considerable deleterious effects on cells or animals. In addition, most of the studies that have compared the toxicity of e-cigarettes with tobacco cigarettes have suggested that e-cigarettes are less toxic than tobacco cigarettes. Nevertheless, scientific evidence regarding the toxicity profile of e-cigarette is insufficient owing to the lack of a standardized research approach. In the future, scientific toxicology data derived from standardized testing protocols including nicotine, ingredients analysis, the various e-cigarette devices made from different materials are urgently needed for thorough toxicology assessment. This review aims to update the toxicity profiles, identify knowledge gaps, and outline future directions for e-cigarettes research, which would greatly benefit public health professionals.
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Affiliation(s)
- Guanghe Wang
- Department of Environmental Health, School of Public Health, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Wenjing Liu
- Science and Technology Museum of Inner Mongolia , Hohhot, Inner Mongolia , China
| | - Weimin Song
- Department of Environmental Health, School of Public Health and the Key Laboratory of Public Health Safety, Fudan University , Shanghai , China
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36
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Abstract
Purpose of the review The purpose of this review is to describe current trends in e-cigarette use, provide an overview of the potential health risks and benefits, and discuss tobacco policy and regulatory considerations. Recent Findings E-cigarette use is popular among youth and adults, despite limited evidence about the long-term risks or benefits. Internationally there is wide variability in how e-cigarettes are classified, which has also led to large differences in regulations on these products. Regulatory policies that strike a balance between the potential benefit of these devices for adult smokers who are trying to quit smoking with reducing the appeal and addictive potential for youth are critically needed. Summary Continued research on the health effects and consequences of e-cigarette use will be essential to inform e-cigarette product standards and tobacco regulatory policies as scientific research strives to keep pace with the ever-changing landscape of e-cigarette technology.
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Affiliation(s)
- Krysten W Bold
- Yale University School of Medicine, 34 Park Street CMHC, New Haven, CT 06519
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37
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Rankin GD, Wingfors H, Uski O, Hedman L, Ekstrand-Hammarström B, Bosson J, Lundbäck M. The toxic potential of a fourth-generation E-cigarette on human lung cell lines and tissue explants. J Appl Toxicol 2019; 39:1143-1154. [PMID: 30957912 DOI: 10.1002/jat.3799] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/21/2019] [Accepted: 02/26/2019] [Indexed: 12/19/2022]
Abstract
The use of electronic cigarettes (E-cigs) is rapidly increasing. The latest generation of E-cigs is highly customizable, allowing for high heating coil temperatures. The aim of this study was to assess the toxic potential of a fourth-generation E-cig. Aerosols generated from E-liquid with (24 mg/mL) and without nicotine, using a fourth-generation E-cig, were chemically analysed and compared with cigarette smoke (K3R4F). Human lung epithelial cell lines and distal lung tissue explants were exposed to E-cig vapour extract (EVE) and cigarette smoke extract for 24 hours and assessed for viability, inflammation, oxidative stress and genotoxicity. E-cig aerosols contained measurable levels of volatile organic compounds, aldehydes and polycyclic aromatic hydrocarbons, in general, to a much lesser extent than cigarette smoke. Higher levels of certain carbonyls, e.g. formaldehyde, were detected in the E-cig aerosols. EVEs decreased cell viability of BEAS-2B cells, whereas little effect was seen in A549 cells and distal lung tissue. The nicotine-containing EVE caused a greater decrease in cell viability and significant increase in DNA damage than the nicotine-free EVE. Increased cytotoxicity, reactive oxygen species production and genotoxicity were seen with cells and tissue exposed to cigarette smoke extract compared with EVEs. Although E-cig aerosols were less toxic than cigarette smoke, it was not benign. Moreover, the EVE containing nicotine was more toxic than the nicotine-free EVE. More research is needed on the short- and long-term health effects of vaping and the usage of newly emerging E-cig devices to evaluate better the potential negative effects of E-cigs on human health.
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Affiliation(s)
- Gregory D Rankin
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine and Allergy, Umeå University, Umeå, Sweden
| | - Håkan Wingfors
- Swedish Defence Research Agency, CBRN Defence and Security, Umeå, Sweden
| | - Oskari Uski
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine and Allergy, Umeå University, Umeå, Sweden
| | - Linnéa Hedman
- Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine, The OLIN Unit, Umeå University, Umeå, Sweden.,Department of Health Sciences, Division of Nursing, Luleå University of Technology, Luleå, Sweden
| | | | - Jenny Bosson
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine and Allergy, Umeå University, Umeå, Sweden
| | - Magnus Lundbäck
- Karolinska Institutet, Department of Clinical Sciences, Division of Cardiology, Danderyd University Hospital, Stockholm, Sweden
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Czekala L, Simms L, Stevenson M, Tschierske N, Maione AG, Walele T. Toxicological comparison of cigarette smoke and e-cigarette aerosol using a 3D in vitro human respiratory model. Regul Toxicol Pharmacol 2019; 103:314-324. [DOI: 10.1016/j.yrtph.2019.01.036] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/25/2019] [Accepted: 01/28/2019] [Indexed: 10/27/2022]
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Hayes AW, Li R, Hoeng J, Iskandar A, Peistch MC, Dourson ML. New approaches to risk assessment of chemical mixtures. TOXICOLOGY RESEARCH AND APPLICATION 2019. [DOI: 10.1177/2397847318820768] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
| | - Roman Li
- Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Dübendorf, Switzerland
- Philip Morris International (PMI) Research & Development, Neuchâtel, Switzerland
| | - Julia Hoeng
- Philip Morris International (PMI) Research & Development, Neuchâtel, Switzerland
| | - Anita Iskandar
- Philip Morris International (PMI) Research & Development, Neuchâtel, Switzerland
| | - Manuel C Peistch
- Philip Morris International (PMI) Research & Development, Neuchâtel, Switzerland
| | - Michael L Dourson
- Toxicology Excellence for Risk Assessment (TERA), Cincinnati, OH, USA
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40
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Krishnan-Sarin S, Jackson A, Morean M, Kong G, Bold KW, Camenga DR, Cavallo DA, Simon P, Wu R. E-cigarette devices used by high-school youth. Drug Alcohol Depend 2019; 194:395-400. [PMID: 30497057 PMCID: PMC6312472 DOI: 10.1016/j.drugalcdep.2018.10.022] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/23/2018] [Accepted: 10/24/2018] [Indexed: 10/27/2022]
Abstract
Background E-cigarette use rates are high among youth, but there is limited information on the types of e-cigarette devices that are used by youth. Methods During Spring 2017, students from 4 high schools completed surveys on use of e-cigarette devices (cig-a-like, vape/hookah pen, modified devices or mods, and JUUL). Among youth who endorsed ever (lifetime) use of an e-cigarette and of at least one device (n = 875), we assessed 1) prevalence rates of ever and current (past-month) use of each device, 2) use of nicotine in each device, and 3) predictors [age, sex, race, socioeconomic status (SES), other tobacco use] of ever use of each device and of use of single versus multiple devices. Results Cig-a-likes were used least frequently (Ever use: cig-a-likes: 25.4%; vape/hookah pens: 60.6%; JUUL: 64.2%; mods: 71.2%; Current use: cig-a-likes: 7.3%; vape/hookah pens; 18.7%; mods: 33.1%; JUUL: 47.1%;). Nicotine use was highest for JUUL (JUUL: 80.3%; mods: 56.3%; cig-a-likes: 51.4%; vape/hookah pens: 46.8%). Among ever users of single devices, use of JUUL was highest (JUUL: 43%; mods: 32%; vape/hookah pens: 21%; cig-a-likes: 4%). Ever use of all devices, except JUUL, was associated with other tobacco product use. Ever use of JUUL was associated with higher SES. Ever use of multiple devices (two: 34.7%; three: 25.8%; four: 11.7%) compared with a single device (27.8%) was associated with other tobacco product use. Conclusions Targeted regulatory and prevention efforts that consider the use of multiple e-cigarette devices are needed to lower youth e-cigarette use rates.
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Affiliation(s)
- Suchitra Krishnan-Sarin
- Department of Psychiatry, Yale University School of Medicine, 300 George St. #901, New Haven, CT, 06511, USA.
| | - Asti Jackson
- Department of Psychiatry, Yale University School of Medicine, 300 George St. #901, New Haven, CT, 06511, USA
| | - Meghan Morean
- Department of Psychology, Oberlin College, 120 W. Lorain St., Oberlin, OH, 44074, USA
| | - Grace Kong
- Department of Psychiatry, Yale University School of Medicine, 300 George St. #901, New Haven, CT, 06511, USA
| | - Krysten W Bold
- Department of Psychiatry, Yale University School of Medicine, 300 George St. #901, New Haven, CT, 06511, USA
| | - Deepa R Camenga
- Department of Emergency Medicine, Yale University School of Medicine, 464 Congress Ave. Suite 260, New Haven, CT, 06519, USA
| | - Dana A Cavallo
- Department of Psychiatry, Yale University School of Medicine, 300 George St. #901, New Haven, CT, 06511, USA
| | - Patricia Simon
- Department of Psychiatry, Yale University School of Medicine, 300 George St. #901, New Haven, CT, 06511, USA
| | - Ran Wu
- Department of Psychiatry, Yale University School of Medicine, 300 George St. #901, New Haven, CT, 06511, USA
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Alanazi H, Park HJ, Chakir J, Semlali A, Rouabhia M. Comparative study of the effects of cigarette smoke and electronic cigarettes on human gingival fibroblast proliferation, migration and apoptosis. Food Chem Toxicol 2018; 118:390-398. [PMID: 29800583 DOI: 10.1016/j.fct.2018.05.049] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 04/08/2018] [Accepted: 05/19/2018] [Indexed: 12/12/2022]
Abstract
In an effort to reduce smoking-related diseases, alternative products such as e-cigarettes have been proposed. However, despite their growing popularity, the potential toxicity of e-cigarettes remains largely unknown. In this study, human gingival fibroblasts were repeatedly exposed to cigarette smoke condensate (CSC) and to nicotine-rich (NR) or nicotine-free (NF) e-vapor condensates for 60 min once a day for various time periods. They were then used to perform different analyses. Results indicate that cells exposed to CSC or NR condensates showed an altered morphology and a reduced proliferation rate, as ascertained by MTT and BrdU assays. Fibroblast cultures exposed to either CSC or e-vapor condensates also showed increased levels of TUNEL-positive apoptotic cells, compared to that recorded in the control. Furthermore, the cell scratch test revealed that repeated exposures to CSC or to e-vapor condensates delayed both fibroblast migration and wound healing. It should be noted that CSC was much more damageable to gingival fibroblasts than were the NR and NF e-vapor condensates. The representative chain of damage thus translates to CSC > NR e-vapor condensate > NF e-vapor condensate.
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Affiliation(s)
- Humidah Alanazi
- Groupe de Recherche en Ecologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec, QC, Canada
| | - Hyun Jin Park
- Groupe de Recherche en Ecologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec, QC, Canada
| | - Jamila Chakir
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Abdelhabib Semlali
- Department of Biochemistry, Genome Research Chair, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Mahmoud Rouabhia
- Groupe de Recherche en Ecologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec, QC, Canada.
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Sosnowski TR, Odziomek M. Particle Size Dynamics: Toward a Better Understanding of Electronic Cigarette Aerosol Interactions With the Respiratory System. Front Physiol 2018; 9:853. [PMID: 30038580 PMCID: PMC6046408 DOI: 10.3389/fphys.2018.00853] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/15/2018] [Indexed: 11/17/2022] Open
Abstract
The knowledge of possible acute and long-term health effects of aerosols inhaled from electronic cigarettes (ECs) is still limited partially due to incomplete awareness of physical phenomena related to EC-aerosol dynamics. This short review discusses the basic processes of aerosol transformation (dynamics) upon inhalation, indicating also the need for the accurate determination of the size of droplets in the inhaled EC-mist. The significance of differences in the aerosol particle size distribution for the prediction of regional deposition of inhaled mist in the respiratory system is highlighted as a decisive factor in the interactions of inhaled EC-aerosols with the organism.
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Affiliation(s)
- Tomasz R Sosnowski
- Faculty of Chemical and Process Engineering, Warsaw University of Technology, Warsaw, Poland
| | - Marcin Odziomek
- Faculty of Chemical and Process Engineering, Warsaw University of Technology, Warsaw, Poland
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Kaur G, Muthumalage T, Rahman I. Mechanisms of toxicity and biomarkers of flavoring and flavor enhancing chemicals in emerging tobacco and non-tobacco products. Toxicol Lett 2018; 288:143-155. [PMID: 29481849 PMCID: PMC6549714 DOI: 10.1016/j.toxlet.2018.02.025] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/19/2018] [Accepted: 02/21/2018] [Indexed: 01/11/2023]
Abstract
Tobacco products containing flavorings, such as electronic nicotine delivery devices (ENDS) or e-cigarettes, cigars/cigarillos, waterpipes, and heat-not-burn devices (iQOS) are continuously evolving. In addition to increasing the exposure of teenagers and adults to nicotine containing flavoring products and flavoring enhancers, chances of nicotine addiction through chronic use and abuse also increase. These flavorings are believed to be safe for ingestion, but little information is available about their effects on the lungs. In this review, we have discussed the in vitro and in vivo data on toxicity of flavoring chemicals in lung cells. We have further discussed the common flavoring agents, such as diacetyl and menthol, currently available detection methods, and the toxicological mechanisms associated with oxidative stress, inflammation, mucociliary clearance, and DNA damage in cells, mice, and humans. Finally, we present potential biomarkers that could be utilized for future risk assessment. This review provides crucial parameters important for evaluation of risk associated with flavoring agents and flavoring enhancers used in tobacco products and ENDS. Future studies can be designed to address the potential toxicity of inhaled flavorings and their biomarkers in users as well as in chronic exposure studies.
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Affiliation(s)
- Gurjot Kaur
- Human and Environmental Toxicology, Department of Biology, University of Konstanz, Konstanz, Germany
| | - Thivanka Muthumalage
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, USA
| | - Irfan Rahman
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, USA.
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