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Kiziltunc E, Sabanoglu C, Felekoglu MA, Eyerci N, Karayigit O, Ates O. Association between inflammation and cigarette smoking in cardiac remodeling after acute myocardial infarction. HEART, VESSELS AND TRANSPLANTATION 2022. [DOI: 10.24969/hvt.2022.361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Rocha DFA, Machado-Junior PA, Souza ABF, Castro TDF, Costa GDP, Talvani A, Bezerra FS, Cangussú SD. Lycopene Ameliorates Liver Inflammation and Redox Status in Mice Exposed to Long-Term Cigarette Smoke. BIOMED RESEARCH INTERNATIONAL 2021; 2021:7101313. [PMID: 34869769 PMCID: PMC8639233 DOI: 10.1155/2021/7101313] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/09/2021] [Indexed: 01/11/2023]
Abstract
Cigarette smoke (CS) is the major cause of preventable death worldwide, and it can also cause damage to extrapulmonary organs, such as the liver, mainly due the generation of reactive oxygen species (ROS). The liver is an essential organ for human survival since it is mainly responsible for the body metabolism and among other things and it is the place where many endogenous and exogenous substances undergo biological transformation. Lycopene is a nonprovitamin A carotenoid found in red fruits and vegetables, and its role as a potent antioxidant is well known. In this study, we hypothesized that lycopene could protect mouse liver against long-term CS exposure. Thirty C57BL/6 mice were exposed to twelve cigarette smoke (12 cigarettes per day) for 60 days and pretreated with 25 mg/kg/day or 50 mg/kg/day of lycopene via orogastric gavage. After euthanasia, the hepatic tissue was collected for histopathological, antioxidant defense, oxidative stress, inflammatory, and collagen deposition analysis. Our analysis demonstrated that lycopene results in a suitable outcome to ameliorate the pathological changes, inflammatory and antioxidant profile in a mouse model of long-term CS exposure, and collagen accumulation in the hepatic extracellular matrix. This study demonstrates for the first time that supplementation of lycopene can be a possible pharmacological tool for the treatment of hepatic damage caused by exposure to long-term CS.
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Affiliation(s)
- Daniela Fonseca Abdo Rocha
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
| | - Pedro Alves Machado-Junior
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
| | - Ana Beatriz Farias Souza
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
| | - Thalles de Freitas Castro
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
| | - Guilherme de Paula Costa
- Laboratory of Immunobiology of Inflammation (LABIIN), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
| | - André Talvani
- Laboratory of Immunobiology of Inflammation (LABIIN), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
| | - Frank Silva Bezerra
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
| | - Silvia Dantas Cangussú
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences (DECBI), Institute of Exact and Biological Sciences (ICEB), Federal University of Ouro Preto (UFOP), 35400-00 Ouro Preto, MG, Brazil
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Tellez CS, Juri DE, Phillips LM, Do K, Thomas CL, Willink R, Dye WW, Wu G, Zhou Y, Irshad H, Kishida S, Kiyono T, Belinsky SA. Comparative Genotoxicity and Mutagenicity of Cigarette, Cigarillo, and Shisha Tobacco Products in Epithelial and Cardiac Cells. Toxicol Sci 2021; 184:67-82. [PMID: 34390580 PMCID: PMC8557423 DOI: 10.1093/toxsci/kfab101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Epidemiology studies link cigarillos and shisha tobacco (delivered through a hookah waterpipe) to increased risk for cardiopulmonary diseases. Here we performed a comparative chemical constituent analysis between 3 cigarettes, 3 cigarillos, and 8 shisha tobacco products. The potency for genotoxicity and oxidative stress of each product's generated total particulate matter (TPM) was also assessed using immortalized oral, lung, and cardiac cell lines to represent target tissues. Levels of the carcinogenic carbonyl formaldehyde were 32- to 95-fold greater, while acrolein was similar across the shisha aerosols generated by charcoal heating compared to cigarettes and cigarillos. Electric-mediated aerosol generation dramatically increased acrolein to levels exceeding those in cigarettes and cigarillos by up to 43-fold. Equivalent cytotoxic-mediated cell death and dose response for genotoxicity through induction of mutagenicity and DNA strand breaks was seen between cigarettes and cigarillos, while minimal to no effect was observed with shisha tobacco products. In contrast, increased potency of TPM from cigarillos compared to cigarettes for inducing oxidative stress via reactive oxygen radicals and lipid peroxidation across cell lines was evident, while positivity was seen for shisha tobacco products albeit at much lower levels. Together, these studies provide new insight into the potential harmful effects of cigarillos for causing tobacco-associated diseases. The high level of carbonyls in shisha products, that in turn is impacted by the heating mechanism, reside largely in the gas phase which will distribute throughout the respiratory tract and systemic circulation to likely increase genotoxic stress.
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Affiliation(s)
- Carmen S Tellez
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Daniel E Juri
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Loryn M Phillips
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Kieu Do
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Cindy L Thomas
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Randy Willink
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Wendy W Dye
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Guodong Wu
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Yue Zhou
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Hammad Irshad
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Shosei Kishida
- Departments of Biochemistry and Genetics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Tohru Kiyono
- Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Chiba, Japan
| | - Steven A Belinsky
- Lung Cancer Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
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Miguel JP, Dias ADC, Bettini NR, Sousa SABAD, Durão MPL, Oliveira LVDC, Monedeiro F, Ramalho LNZ, Branco LGS, Sabino JPJ, Durand MDT. Cigarette smoke exposure causes systemic and autonomic cardiocirculatory changes in rats depending on the daily exposure dose. Life Sci 2021; 277:119498. [PMID: 33864817 DOI: 10.1016/j.lfs.2021.119498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 11/15/2022]
Abstract
AIMS To evaluate the systemic changes and autonomic cardiocirculatory control of awaken rats chronically exposed to the cigarette smoke (CS) of 1 or 2 cigarettes/day. MAIN METHODS Rats were exposed to clean air (control) or cigarette smoke of 1 (CS1) or 2 (CS2) cigarettes/animal/day for 30 days. Then, arterial pressure (AP) and heart rate (HR) were recorded in conscious rats to assess spontaneous baroreflex sensitivity and HR and AP variabilities. Evoked baroreflex and cardiac autonomic tone were evaluated by vasoactive drugs and autonomic blockers, respectively. In another group, ventilatory and cardiovascular parameters were recorded under hypoxia and hypercapnia stimulus. At the end of protocols, heart, lung, kidneys and liver were collected for histological analysis. KEY FINDINGS Rats exposed to CS showed morphological changes, being more evident in the CS2 group. Also, less weight gain and cardiac hypertrophy were prominent in CS2 rats. Basal AP and HR, spontaneous baroreflex sensitivity and cardiovascular variabilities were similar among groups. CS exposure progressively blunted the bradycardia response to phenylephrine (-2.2 ± 0.1 vs. -1.7 ± 0.2 vs. -1.5 ± 0.2) while the tachycardia response to sodium nitroprusside was slightly increased compared to control. Vagal tone was not affected by CS, but CS2 rats exhibited higher sympathetic tone (-25 ± 4 vs. -28 ± 4 vs. -56 ± 9) and lower intrinsic HR (411 ± 4 vs. 420 ± 8 vs. 390 ± 6). Exposure to CS of 2 cigarettes also exacerbated the reflex cardiovascular and ventilatory responses to hypoxia and hypercapnia. SIGNIFICANCE CS exposure for 30 days promoted systemic changes and autonomic cardiocirculatory dysfunction in rats depending on the daily exposure dose.
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Affiliation(s)
- João Paulo Miguel
- Medical School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil
| | | | | | | | | | - Lucas Vaz de Castro Oliveira
- Department of Biophysics and Physiology, Postgraduate Program in Pharmaceutical Sciences, Federal University of Piaui, Teresina, PI, Brazil
| | - Fernanda Monedeiro
- Department of Chemistry, Physiology and Basic Pathology, University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Luiz Guilherme S Branco
- Department of Morphology, Physiology and Basic Pathology, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - João Paulo Jacob Sabino
- Department of Biophysics and Physiology, Postgraduate Program in Pharmaceutical Sciences, Federal University of Piaui, Teresina, PI, Brazil
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Azevedo PS, Polegato BF, Paiva S, Costa N, Santos P, Bazan S, Fernandes AAH, Fabro A, Pires V, Tanni SE, Leal Pereira F, Lo A, Grassi L, Campos D, Androcioli V, Zornoff L, Minicucci M. The role of glucose metabolism and insulin resistance in cardiac remodelling induced by cigarette smoke exposure. J Cell Mol Med 2021; 25:1314-1318. [PMID: 33300293 PMCID: PMC7812248 DOI: 10.1111/jcmm.16053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/08/2020] [Accepted: 10/11/2020] [Indexed: 11/29/2022] Open
Abstract
The aim of this study is to evaluate whether the alterations in glucose metabolism and insulin resistance are mechanisms presented in cardiac remodelling induced by the toxicity of cigarette smoke. Male Wistar rats were assigned to the control group (C; n = 12) and the cigarette smoke-exposed group (exposed to cigarette smoke over 2 months) (CS; n = 12). Transthoracic echocardiography, blood pressure assessment, serum biochemical analyses for catecholamines and cotinine, energy metabolism enzymes activities assay; HOMA index (homeostatic model assessment); immunohistochemistry; and Western blot for proteins involved in energy metabolism were performed. The CS group presented concentric hypertrophy, systolic and diastolic dysfunction, and higher oxidative stress. It was observed changes in energy metabolism, characterized by a higher HOMA index, lower concentration of GLUT4 (glucose transporter 4) and lower 3-hydroxyl-CoA dehydrogenase activity, suggesting the presence of insulin resistance. Yet, the cardiac glycogen was depleted, phosphofructokinase (PFK) and lactate dehydrogenase (LDH) increased, with normal pyruvate dehydrogenase (PDH) activity. The activity of citrate synthase, mitochondrial complexes and ATP synthase (adenosine triphosphate synthase) decreased and the expression of Sirtuin 1 (SIRT1) increased. In conclusion, exposure to cigarette smoke induces cardiac remodelling and dysfunction. The mitochondrial dysfunction and heart damage induced by cigarette smoke exposure are associated with insulin resistance and glucose metabolism changes.
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Affiliation(s)
- Paula Schmidt Azevedo
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Bertha F. Polegato
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Sergio Paiva
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Nara Costa
- Faculty of NutritionUFG – Univ Federal de GoiásGoiâniaBrazil
| | - Priscila Santos
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Silmeia Bazan
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | | | - Alexandre Fabro
- Department of Pathology and Legal MedicineRibeirão Preto Medical SchoolUniversity of São PauloRibeirão PretoBrazil
| | - Vanessa Pires
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Suzana E. Tanni
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Filipe Leal Pereira
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Angelo Lo
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Leticia Grassi
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Dijon Campos
- Department of Pathology and Legal MedicineRibeirão Preto Medical SchoolUniversity of São PauloRibeirão PretoBrazil
| | - Vickeline Androcioli
- Experimental Research Unit – UNIPEXBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Leonardo Zornoff
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
| | - Marcos Minicucci
- Department of Internal MedicineBotucatu Medical SchoolSão Paulo State University‐UNESPBotucatuBrazil
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Associations between Lifestyle Factors and Vitamin E Metabolites in the General Population. Antioxidants (Basel) 2020; 9:antiox9121280. [PMID: 33333950 PMCID: PMC7765431 DOI: 10.3390/antiox9121280] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/08/2020] [Accepted: 12/11/2020] [Indexed: 12/31/2022] Open
Abstract
The antioxidant vitamin E (α-tocopherol, α-TOH) protects lipids from oxidation by reactive oxygen species. We hypothesized that lifestyle factors associate with vitamin E metabolism marked by urinary α-tocopheronolactone hydroquinone (α-TLHQ) and α-carboxymethyl-hydroxychroman (α-CEHC levels), as potential reflection of lipid oxidation. We conducted a cross-sectional study in the Netherlands Epidemiology of Obesity Study. Serum α-TOH, and urinary α-TLHQ and α-CEHC were quantified by liquid chromatography coupled with tandem mass spectrometry. Information on the lifestyle factors (sleep, physical activity (PA), smoking and alcohol) were collected through questionnaires. Multivariable linear regression analyses were performed to assess the associations between the lifestyle factors and α-TOH measures. A total of 530 participants (46% men) were included with mean (SD) age of 56 (6) years. Of the examined lifestyle factors, only poor sleep was associated with a higher serum α-TOH (mean difference: 4% (95% CI: 1, 7%)). Current smoking was associated with higher urinary α-CEHC (32%: (14%, 53%)), with evidence of a dose–response relationship with smoking intensity (low pack years, 24% (2, 52%); high pack years, 55% (25, 93%)). Moderate physical activity was associated with a lower α-TLHQ relative to α-CEHC (−17%: (−26, −6%), compared with low PA). Only specific lifestyle factors associate with vitamin E metabolism. Examining serum α-TOH does not provide complete insight in vitamin E antioxidant capacity.
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Abstract
PURPOSE Hyperlipidemia, characterized by an increase in circulating lipid levels, doubles the chance of developing cardiovascular diseases. It prompts inflammation, immune activation, and oxidative stress in the bloodstream and organs of rats. Thus, we theorized that the metabolism of purines, an immunomodulatory mechanism, is altered in cells involved in the development of cardiovascular diseases. METHODS Therefore, we induced acute hyperlipidemia in Wistar rats with Poloxamer-407 and euthanized the animals 36 h later. The leucocyte differential, the rate of purine metabolism on the surface of platelets and heart cells, and markers of oxidative stress in the heart tissue were evaluated. These parameters were also assessed in animals pretreated for 30 days with curcumin and/or rutin. RESULTS Hyperlipidemia increased the hydrolyses of adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) in platelets. In heart cells, the metabolism of ATP and adenosine (ADO) were increased, while ADP hydrolysis was reduced. Additionally, lipid damage and antioxidant defenses were increased in heart homogenates. Hyperlipidemic rats also exhibited a reduced percentage of eosinophils and lymphocytes. CONCLUSION Together, these findings are indicative of an increased risk of developing cardiovascular diseases in hyperlipidemic rats. The pretreatments with antioxidants reverted some of the changes prompted by hyperlipidemia preventing detrimental changes in the cells and tissues. Graphical Abstract.
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Pavlou P, Antoniadou I, Peraki A, Vitsos A, Dallas P, Mostratos D, Deliconstantinos G, Papaioannou G, Grando SA, Rallis M. Protective Effects of Pinus halepensis Bark Extract and Nicotine on Cigarette Smoke-induced Oxidative Stress in Keratinocytes. In Vivo 2020; 34:1835-1843. [PMID: 32606153 DOI: 10.21873/invivo.11978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 04/21/2020] [Accepted: 04/29/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND/AIM Cigarette smoke (CS) is a major environmental health threat. The oxidative stress induced by CS on keratinocytes and the possible protective effect of nicotine, its receptor inhibitors, and Pinus halepensis bark extract in relation to known antioxidants were investigated. MATERIALS AND METHODS Primary mouse keratinocytes were exposed to cigarette smoke in the presence and absence of Pinus halepensis bark extract (1 μg/ml), rutin (50 μM) and ascorbic acid (250 μM), nicotine (1 μM) with or without mecamylamine (5 μM) and α-bungarotoxin (0.1 μM). Keratinocyte viability and oxidative stress were evaluated by MTT and fluorescence assays. RESULTS Pinus halepensis bark extract decreased the oxidative stress and increased the viability of keratinocytes, and moreover, these effects were more pronounced compared to the mixture of rutin and L-ascorbic acid. Nicotine significantly enhanced the viability potentiation of the beneficial effect induced by Pinus halepensis bark extract. Mecamylamine and α-bungarotoxin showed no specific effect. CONCLUSION Pinus halepensis bark extract in combination with nicotine may successfully reverse skin damage induced by cigarette smoke.
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Affiliation(s)
- Panagoula Pavlou
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
| | - Ioanna Antoniadou
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
| | - Asimina Peraki
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
| | - Andreas Vitsos
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
| | - Paraskevas Dallas
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
| | - Dimitrios Mostratos
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
| | - Georgios Deliconstantinos
- National and Kapodistrian University of Athens, School of Medicine, Department of Experimental Physiology, Athens, Greece
| | - Georgios Papaioannou
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
| | - Sergei A Grando
- University of California, Health Gottschalk Medical Plaza, Institute for Immunology, Irvine, CA, U.S.A
| | - Michail Rallis
- National and Kapodistrian University of Athens, School of Health Sciences, Department of Pharmacy, Athens, Greece
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Wavreil FD, Heggland SJ. Cinnamon-flavored electronic cigarette liquids and aerosols induce oxidative stress in human osteoblast-like MG-63 cells. Toxicol Rep 2019; 7:23-29. [PMID: 31871899 PMCID: PMC6909334 DOI: 10.1016/j.toxrep.2019.11.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 11/27/2019] [Accepted: 11/28/2019] [Indexed: 12/26/2022] Open
Abstract
As noncombustible nicotine delivery devices, electronic cigarettes (e-cigarettes) are the most popular tobacco product among youth. The widespread popularity of e-cigarettes combined with possible health consequences suggest a need to further research health hazards associated with e-cigarette use. Since conventional tobacco use is a risk factor for osteoporosis, this study investigates the impact of nicotine-free, cinnamon-flavored e-cigarette liquid (e-liquid) on bone-forming osteoblasts compared to flavorless e-liquid. Human tumor-derived osteoblast-like MG-63 cells were exposed for 24 h or 48 h to 0.0.4 %, 0.04 %, 0.4 % or 1 % of unvaped e-liquid or 0.0025 %, 0.025 %, 0.25 %, 1 % or 2.5 % of aerosol condensate in addition to a culture medium only control. Changes in cell viability were assessed by MTT assay, and the expression of a key bone protein, collagen type I, was analyzed by immunofluorescence. Production of reactive oxygen species (ROS) was detected by fluorometry to assess oxidative stress. Cell viability decreased in a dose-dependent manner, and ROS production increased, which was most pronounced with cinnamon-flavored e-liquids. There were no detectable changes in collagen type I protein following exposure to any of the aerosol condensates. This study demonstrates osteoblast-like cells are sensitive to both e-liquids and aerosol condensates and suggests the cytotoxicity of cinnamon-flavored e-liquids might be associated with oxidative stress rather than changes in collagen type I protein expression. This in vitro study provides insight into the potential impacts of e-cigarette use on bone cells.
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Affiliation(s)
| | - Sara J. Heggland
- Department of Biology, The College of Idaho, 2112 Cleveland Blvd, Caldwell, ID, 83605, USA
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