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Li M, Chen Z, Yang X, Li W. Causal relationship between iron deficiency anemia and asthma: a Mendelian randomization study. Front Pediatr 2024; 12:1362156. [PMID: 38853780 PMCID: PMC11158623 DOI: 10.3389/fped.2024.1362156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 05/06/2024] [Indexed: 06/11/2024] Open
Abstract
Background Observational studies have suggested an association between iron deficiency anemia (IDA) and asthma, which may affect the occurrence of asthma. However, whether IDA is a new management goal for asthma remains to be determined. Objective We conducted a two-sample Mendelian randomization(MR)analysis to assess the association between IDA and asthma. Methods We performed a two-sample MR study to assess a causal relationship between IDA (ncase = 12,434, ncontrol = 59,827) and asthma (ncase = 20,629, ncontrol = 135,449). Inverse variance weighted (IVW) was used as the primary method for the analyses. Furthermore, we used weighted medians and MR-Egger to enhance robustness. Data linking genetic variation to IDA and asthma were combined to assess the impact of IDA on asthma risk. Results There are five single nucleotide polymorphisms (SNPs) were used as genetic tool variables for exposure factors. Genetically determined IDA was significantly associated with an increased risk of asthma (OR = 1.37, 95% CI: 1.09-1.72, p = 0.007). There was little heterogeneity in the MR studies and no evidence of level pleiotropy was found. Conclusions In our MR study, our findings emphasize that IDA may be associated with a high risk of asthma, indicating a potential role for IDA in the development of asthma. Future research needs to elucidate its potential mechanisms to pave the way for the prevention and treatment of asthma.
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Affiliation(s)
| | | | - Xin Yang
- Department of Pediatrics, Daping Hospital, Army Medical University, Chongqing, China
| | - Wanwei Li
- Department of Pediatrics, Daping Hospital, Army Medical University, Chongqing, China
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2
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Wen J, Wang C, Xia J, Giri M, Guo S. Relationship between serum iron and blood eosinophil counts in asthmatic adults: data from NHANES 2011-2018. Front Immunol 2023; 14:1201160. [PMID: 37731511 PMCID: PMC10507334 DOI: 10.3389/fimmu.2023.1201160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 08/21/2023] [Indexed: 09/22/2023] Open
Abstract
Background So far, quite a few studies have revealed that systemic iron levels are related to asthmatic inflammatory reactions. And most studies have focused on the correlation between systemic iron levels and asthma, with inconsistent findings. Yet, few studies have investigated the connection between serum iron and blood eosinophil counts. Hence, we have explored the connection between serum iron and blood eosinophil counts in asthmatics by utilizing data from NHANES. Methods A total of 2549 individuals were included in our study after screening NHANES participants from 2011 to 2018. The linear regression model and XGBoost model were used to discuss the potential connection. Linear or nonlinear association was further confirmed by the generalized additive model and the piecewise linear regression model. And we also performed stratified analyses to figure out specific populations. Results In the multivariable linear regression models, we discovered that serum iron levels were inversely related to blood eosinophil counts in asthmatic adults. Simultaneously, we found that for every unit increase in serum iron (umol/L), blood eosinophil counts reduced by 1.41/uL in model 3, which adjusted for all variables excluding the analyzed variables. Furthermore, the XGBoost model of machine learning was applied to assess the relative importance of chosen variables, and it was determined that vitamin C intake, age, vitamin B12 intake, iron intake, and serum iron were the five most important variables on blood eosinophil counts. And the generalized additive model and piecewise linear regression model further verify this linear and inverse association. Conclusion Our investigation discovered that the linear and inverse association of serum iron with blood eosinophil counts in asthmatic adults, indicating that serum iron might be related to changes in the immunological state of asthmatics. Our work offers some new thoughts for next research on asthma management and therapy. Ultimately, we hope that more individuals become aware of the role of iron in the onset, development, and treatment of asthma.
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Affiliation(s)
- Jun Wen
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical University, Chongqing, China
| | - Changfen Wang
- Department of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical University, Chongqing, China
| | - Jing Xia
- Department of Respiratory and Critical Care Medicine, The Third Affiliated Hospital of Chongqing Medical University, Chongqing Medical University, Chongqing, China
| | - Mohan Giri
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical University, Chongqing, China
| | - Shuliang Guo
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical University, Chongqing, China
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3
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Fakhimahmadi A, Hasanaj I, Hofstetter G, Pogner C, Gorfer M, Wiederstein M, Szepannek N, Bianchini R, Dvorak Z, Jensen SA, Berger M, Jensen-Jarolim E, Hufnagl K, Roth-Walter F. Nutritional Provision of Iron Complexes by the Major Allergen Alt a 1 to Human Immune Cells Decreases Its Presentation. Int J Mol Sci 2023; 24:11934. [PMID: 37569310 PMCID: PMC10418924 DOI: 10.3390/ijms241511934] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/14/2023] [Accepted: 07/20/2023] [Indexed: 08/13/2023] Open
Abstract
Alternaria alternata is a common fungus strongly related with severe allergic asthma, with 80% of affected individuals being sensitized solely to its major allergen Alt a 1. Here, we assessed the function of Alt a 1 as an innate defense protein binding to micronutrients, such as iron-quercetin complexes (FeQ2), and its impact on antigen presentation in vitro. Binding of Alt a 1 to FeQ2 was determined in docking calculations. Recombinant Alt a 1 was generated, and binding ability, as well as secondary and quaternary structure, assessed by UV-VIS, CD, and DLS spectroscopy. Proteolytic functions were determined by casein and gelatine zymography. Uptake of empty apo- or ligand-filled holoAlt a 1 were assessed in human monocytic THP1 cells under the presence of dynamin and clathrin-inhibitors, activation of the Arylhydrocarbon receptor (AhR) using the human reporter cellline AZ-AHR. Human PBMCs were stimulated and assessed for phenotypic changes in monocytes by flow cytometry. Alt a 1 bound strongly to FeQ2 as a tetramer with calculated Kd values reaching pico-molar levels and surpassing affinities to quercetin alone by a factor of 5000 for the tetramer. apoAlt a 1 but not holoAlta 1 showed low enzymatic activity against casein as a hexamer and gelatin as a trimer. Uptake of apo- and holo-Alt a 1 occurred partly clathrin-dependent, with apoAlt a 1 decreasing labile iron in THP1 cells and holoAlt a 1 facilitating quercetin-dependent AhR activation. In human PBMCs uptake of holoAlt a 1 but not apoAlt a 1 significantly decreased the surface expression of the costimulatory CD86, but also of HLADR, thereby reducing effective antigen presentation. We show here for the first time that the presence of nutritional iron complexes, such as FeQ2, significantly alters the function of Alt a 1 and dampens the human immune response, thereby supporting the notion that Alt a 1 only becomes immunogenic under nutritional deprivation.
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Affiliation(s)
- Aila Fakhimahmadi
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria
| | - Ilir Hasanaj
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
| | - Gerlinde Hofstetter
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria
| | - Clara Pogner
- Bioresources Unit, Center for Health & Bioresources, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria; (C.P.); (M.G.)
| | - Markus Gorfer
- Bioresources Unit, Center for Health & Bioresources, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria; (C.P.); (M.G.)
| | - Markus Wiederstein
- Department of Biosciences, University of Salzburg, 5020 Salzburg, Austria;
| | - Nathalie Szepannek
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
| | - Rodolfo Bianchini
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
| | - Zdenek Dvorak
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, 779 00 Olomouc, Czech Republic;
| | - Sebastian A. Jensen
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
| | - Markus Berger
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
| | - Erika Jensen-Jarolim
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria
| | - Karin Hufnagl
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria
| | - Franziska Roth-Walter
- Comparative Medicine, The Interuniversity Messerli Research Institute, 1210 Vienna, Austria; (A.F.); (I.H.); (G.H.); (N.S.); (R.B.); (S.A.J.); (M.B.); (E.J.-J.); (K.H.)
- Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria
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4
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Mineral Micronutrients in Asthma. Nutrients 2021; 13:nu13114001. [PMID: 34836256 PMCID: PMC8625329 DOI: 10.3390/nu13114001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/07/2021] [Accepted: 11/08/2021] [Indexed: 01/01/2023] Open
Abstract
Asthma represents one of the most common medical issues in the modern world. It is a chronic inflammatory disease characterized by persistent inflammation of the airways and disturbances in redox status, leading to hyperresponsiveness of bronchi and airway obstruction. Apart from classical risk factors such as air pollution, family history, allergies, or obesity, disturbances of the levels of micronutrients lead to impairments in the defense mechanisms of the affected organism against oxidative stress and proinflammatory stimuli. In the present review, the impact of micronutrients on the prevalence, severity, and possible risk factors of asthma is discussed. Although the influence of classical micronutrients such as selenium, copper, or zinc are well known, the effects of those such as iodine or manganese are only rarely mentioned. As a consequence, the aim of this paper is to demonstrate how disturbances in the levels of micronutrients and their supplementation might affect the course of asthma.
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5
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Chan Y, Raju Allam VSR, Paudel KR, Singh SK, Gulati M, Dhanasekaran M, Gupta PK, Jha NK, Devkota HP, Gupta G, Hansbro PM, Oliver BGG, Chellappan DK, Dua K. Nutraceuticals: unlocking newer paradigms in the mitigation of inflammatory lung diseases. Crit Rev Food Sci Nutr 2021:1-31. [PMID: 34613853 DOI: 10.1080/10408398.2021.1986467] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Persistent respiratory tract inflammation contributes to the pathogenesis of various chronic respiratory diseases, such as asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis. These inflammatory respiratory diseases have been a major public health concern as they are the leading causes of worldwide mortality and morbidity, resulting in heavy burden on socioeconomic growth throughout these years. Although various therapeutic agents are currently available, the clinical applications of these agents are found to be futile due to their adverse effects, and most patients remained poorly controlled with a low quality of life. These drawbacks have necessitated the development of novel, alternative therapeutic agents that can effectively improve therapeutic outcomes. Recently, nutraceuticals such as probiotics, vitamins, and phytochemicals have gained increasing attention due to their nutritional properties and therapeutic potential in modulating the pathological mechanisms underlying inflammatory respiratory diseases, which could ultimately result in improved disease control and overall health outcomes. As such, nutraceuticals have been held in high regard as the possible alternatives to address the limitations of conventional therapeutics, where intensive research are being performed to identify novel nutraceuticals that can positively impact various inflammatory respiratory diseases. This review provides an insight into the utilization of nutraceuticals with respect to their molecular mechanisms targeting multiple signaling pathways involved in the pathogenesis of inflammatory respiratory diseases.
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Affiliation(s)
- Yinghan Chan
- School of Pharmacy, International Medical University (IMU), Kuala Lumpur, Malaysia
| | | | - Keshav Raj Paudel
- Centre for Inflammation, Centenary Institute, Sydney, NSW, Australia.,School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Sachin K Singh
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Monica Gulati
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Muralikrishnan Dhanasekaran
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, Alabama, USA
| | - Piyush Kumar Gupta
- Department of Life Sciences, School of Basic Sciences and Research (SBSR), Sharda University, Greater Noida, Uttar Pradesh, India
| | - Niraj Kumar Jha
- Department of Biotechnology, School of Engineering & Technology (SET), Sharda University, Greater Noida, Uttar Pradesh, India
| | - Hari Prasad Devkota
- Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto City, Kumamoto, Japan
| | - Gaurav Gupta
- School of Pharmacy, Suresh Gyan Vihar University, Jagatpura, Jaipur, India
| | - Philip M Hansbro
- Centre for Inflammation, Centenary Institute, Sydney, NSW, Australia.,School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Brian Gregory George Oliver
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia.,Woolcock Institute of Medical Research, University of Sydney, Sydney, NSW, Australia
| | - Dinesh Kumar Chellappan
- Department of Life Sciences, School of Pharmacy, International Medical University, Kuala Lumpur, Malaysia
| | - Kamal Dua
- Department of Biotechnology, School of Engineering & Technology (SET), Sharda University, Greater Noida, Uttar Pradesh, India.,Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney, Ultimo, NSW, Australia.,Faculty of Health, Australian Research Centre in Complementary and Integrative Medicine, University of Technology Sydney, Ultimo, NSW, Australia
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6
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Allam VSRR, Chellappan DK, Jha NK, Shastri MD, Gupta G, Shukla SD, Singh SK, Sunkara K, Chitranshi N, Gupta V, Wich PR, MacLoughlin R, Oliver BGG, Wernersson S, Pejler G, Dua K. Treatment of chronic airway diseases using nutraceuticals: Mechanistic insight. Crit Rev Food Sci Nutr 2021; 62:7576-7590. [PMID: 33977840 DOI: 10.1080/10408398.2021.1915744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Respiratory diseases, both acute and chronic, are reported to be the leading cause of morbidity and mortality, affecting millions of people globally, leading to high socio-economic burden for the society in the recent decades. Chronic inflammation and decline in lung function are the common symptoms of respiratory diseases. The current treatment strategies revolve around using appropriate anti-inflammatory agents and bronchodilators. A range of anti-inflammatory agents and bronchodilators are currently available in the market; however, the usage of such medications is limited due to the potential for various adverse effects. To cope with this issue, researchers have been exploring various novel, alternative therapeutic strategies that are safe and effective to treat respiratory diseases. Several studies have been reported on the possible links between food and food-derived products in combating various chronic inflammatory diseases. Nutraceuticals are examples of such food-derived products which are gaining much interest in terms of its usage for the well-being and better human health. As a consequence, intensive research is currently aimed at identifying novel nutraceuticals, and there is an emerging notion that nutraceuticals can have a positive impact in various respiratory diseases. In this review, we discuss the efficacy of nutraceuticals in altering the various cellular and molecular mechanisms involved in mitigating the symptoms of respiratory diseases.
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Affiliation(s)
- Venkata Sita Rama Raju Allam
- Department of Medical Biochemistry and Microbiology, Biomedical Centre (BMC), Uppsala University, Uppsala, Sweden
| | - Dinesh Kumar Chellappan
- Department of Life Sciences, School of Pharmacy, International Medical University (IMU), Kuala Lumpur, Malaysia
| | - Niraj Kumar Jha
- Department of Biotechnology, School of Engineering & Technology (SET), Sharda University, Greater Noida, Uttar Pradesh, India
| | - Madhur D Shastri
- School of Health Sciences, College of Health and Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Gaurav Gupta
- School of Pharmacy, Suresh Gyan Vihar University, Jagatpura, Jaipur, India
| | - Shakti D Shukla
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute (HMRI), University of Newcastle, New Lambton Heights, Newcastle, New South Wales, Australia
| | - Sachin K Singh
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Krishna Sunkara
- Emergency Clinical Management, Intensive Care Unit, John Hunter Hospital, Newcastle, New South Wales, Australia
| | - Nitin Chitranshi
- Faculty of Medicine, Health and Human Sciences, Macquarie University, North Ryde, New South Wales, Australia
| | - Vivek Gupta
- Faculty of Medicine, Health and Human Sciences, Macquarie University, North Ryde, New South Wales, Australia
| | - Peter R Wich
- School of Chemical Engineering, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Nanomedicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Ronan MacLoughlin
- Aerogen, IDA Business Park, Dangan, Galway, Ireland.,School of Pharmacy & Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland.,School of Pharmacy and Pharmaceutical Sciences, Trinity College, Dublin, Ireland
| | - Brian Gregory George Oliver
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, Australia.,Woolcock Institute of Medical Research, The University of Sydney, Sydney, Australia
| | - Sara Wernersson
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Gunnar Pejler
- Department of Medical Biochemistry and Microbiology, Biomedical Centre (BMC), Uppsala University, Uppsala, Sweden.,Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Kamal Dua
- Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney, Sydney, Australia
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Nutritional immunity: the impact of metals on lung immune cells and the airway microbiome during chronic respiratory disease. Respir Res 2021; 22:133. [PMID: 33926483 PMCID: PMC8082489 DOI: 10.1186/s12931-021-01722-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 04/15/2021] [Indexed: 12/15/2022] Open
Abstract
Nutritional immunity is the sequestration of bioavailable trace metals such as iron, zinc and copper by the host to limit pathogenicity by invading microorganisms. As one of the most conserved activities of the innate immune system, limiting the availability of free trace metals by cells of the immune system serves not only to conceal these vital nutrients from invading bacteria but also operates to tightly regulate host immune cell responses and function. In the setting of chronic lung disease, the regulation of trace metals by the host is often disrupted, leading to the altered availability of these nutrients to commensal and invading opportunistic pathogenic microbes. Similarly, alterations in the uptake, secretion, turnover and redox activity of these vitally important metals has significant repercussions for immune cell function including the response to and resolution of infection. This review will discuss the intricate role of nutritional immunity in host immune cells of the lung and how changes in this fundamental process as a result of chronic lung disease may alter the airway microbiome, disease progression and the response to infection.
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8
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Latent-space embedding of expression data identifies gene signatures from sputum samples of asthmatic patients. BMC Bioinformatics 2020; 21:457. [PMID: 33059594 PMCID: PMC7560063 DOI: 10.1186/s12859-020-03785-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 09/28/2020] [Indexed: 11/30/2022] Open
Abstract
Background The pathogenesis of asthma is a complex process involving multiple genes and pathways. Identifying biomarkers from asthma datasets, especially those that include heterogeneous subpopulations, is challenging. Potentially, autoencoders provide ideal frameworks for such tasks as they can embed complex, noisy high-dimensional gene expression data into a low-dimensional latent space in an unsupervised fashion, enabling us to extract distinguishing features from expression data. Results Here, we developed a framework combining a denoising autoencoder and a supervised learning classifier to identify gene signatures related to asthma severity. Using the trained autoencoder with 50 hidden units, we found that hierarchical clustering on the low-dimensional embedding corresponds well with previously defined and clinically relevant clusters of patients. Moreover, each hidden unit has contributions from each of the genes, and pathway analysis of these contributions shows that the hidden units are significantly enriched in known asthma-related pathways. We then used genes that contribute most to the hidden units to develop a secondary random-forest classifier for directly predicting asthma severity. The feature importance metric from this classifier identified a signature based on 50 key genes, which are associated with severity. Furthermore, we can use these key genes to successfully estimate FEV1/FVC ratios across patients, via support-vector-machine regression. Conclusion We found that the denoising autoencoder framework can extract meaningful patterns corresponding to functional gene groups and patient clusters from the gene expression of asthma patients.
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9
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Sato K, Inoue S, Igarashi A, Tokairin Y, Yamauchi K, Kimura T, Nishiwaki M, Nemoto T, Nakano H, Sato M, Machida H, Yang S, Minegishi Y, Furuyama K, Watanabe M, Shibata Y. Effect of Iron Deficiency on a Murine Model of Smoke-induced Emphysema. Am J Respir Cell Mol Biol 2020; 62:588-597. [DOI: 10.1165/rcmb.2018-0239oc] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- Kento Sato
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Sumito Inoue
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Akira Igarashi
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Yoshikane Tokairin
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Keiko Yamauchi
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Tomomi Kimura
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Michiko Nishiwaki
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Takako Nemoto
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Hiroshi Nakano
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Masamichi Sato
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Hiroyoshi Machida
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Sujeong Yang
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Yukihiro Minegishi
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Kodai Furuyama
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Masafumi Watanabe
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University Faculty of Medicine, Yamagata, Japan; and
| | - Yoko Shibata
- Department of Pulmonary Medicine, Fukushima Medical University, Fukushima, Japan
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10
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Santos KD, Traebert J, Piovezan AP, Silva JD. Relevance of the first thousand days of life to the development of wheezing in children aged 6-7 years. Allergol Immunopathol (Madr) 2020; 48:270-280. [PMID: 32284262 DOI: 10.1016/j.aller.2019.12.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 11/27/2019] [Accepted: 12/17/2019] [Indexed: 12/22/2022]
Abstract
INTRODUCTION The first thousand days of life are a critical stage for the development of respiratory and immune systems. Many events in this period may be associated with wheezing in childhood. OBJECTIVE This study aimed to investigate the association between early life determinants and wheezing in children aged 6-7 years. MATERIALS AND METHODS Population-based case-control study using early-life related questions. We used the International Study of Asthma and Allergies in Childhood questionnaire to assess wheezing symptoms. Multiple logistic regressions were performed according to a hierarchical framework, considering the complex dynamic of wheezing/asthma and potential interaction between different levels of determination. RESULTS A total of 820 children were included, from which 162 reported wheezing symptoms (19.7%). Multivariable analysis identified socioeconomic conditions (OR 2.08, 95% CI 1.08-4.00), family history of asthma (OR 2.28, 95% CI 1.37-3.75), vaginal discharge that required treatment during pregnancy (OR 1.68, 95% CI 1.00-2.83), neonatal hyperbilirubinemia (OR 2.00, 95% CI 1.17-3.42), anemia and intestinal parasitosis in the first two years (OR 2.28, 95% CI 1.22-4.25; OR 1.72, 95% CI 1.02-2.92, respectively) independently associated to wheezing at 6-7 years. Intended pregnancy was associated with reduced wheezing (OR 0.47, 95% CI 0.28-0.77). CONCLUSIONS Several factors were associated with wheezing in childhood. Considering that intended pregnancy reduced wheezing and other associated exposures are considered modifiable, these findings may guide the planning of strategies to decrease the susceptibility to asthma symptoms in childhood.
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Affiliation(s)
- Karoliny Dos Santos
- Postgraduate Program in Health Sciences, University of Southern Santa Catarina (UNISUL), Av. Pedra Branca, 25, Cidade Universitária Pedra Branca, 88137-270, Palhoça, Santa Catarina, SC, Brazil.
| | - Jefferson Traebert
- Postgraduate Program in Health Sciences, University of Southern Santa Catarina (UNISUL), Av. Pedra Branca, 25, Cidade Universitária Pedra Branca, 88137-270, Palhoça, Santa Catarina, SC, Brazil.
| | - Anna Paula Piovezan
- Postgraduate Program in Health Sciences, University of Southern Santa Catarina (UNISUL), Av. Pedra Branca, 25, Cidade Universitária Pedra Branca, 88137-270, Palhoça, Santa Catarina, SC, Brazil.
| | - Jane da Silva
- Department of Internal Medicine and Allergy Clinic of Professor Polydoro Ernani de São Thiago University Hospital, Federal University of Santa Catarina (UFSC), Florianopolis, SC, Brazil.
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11
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Ghio AJ, Soukup JM, Dailey LA, Madden MC. Air pollutants disrupt iron homeostasis to impact oxidant generation, biological effects, and tissue injury. Free Radic Biol Med 2020; 151:38-55. [PMID: 32092410 PMCID: PMC8274387 DOI: 10.1016/j.freeradbiomed.2020.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 01/27/2020] [Accepted: 02/10/2020] [Indexed: 02/07/2023]
Abstract
Air pollutants cause changes in iron homeostasis through: 1) a capacity of the pollutant, or a metabolite(s), to complex/chelate iron from pivotal sites in the cell or 2) an ability of the pollutant to displace iron from pivotal sites in the cell. Through either pathway of disruption in iron homeostasis, metal previously employed in essential cell processes is sequestered after air pollutant exposure. An absolute or functional cell iron deficiency results. If enough iron is lost or is otherwise not available within the cell, cell death ensues. However, prior to death, exposed cells will attempt to reverse the loss of requisite metal. This response of the cell includes increased expression of metal importers (e.g. divalent metal transporter 1). Oxidant generation after exposure to air pollutants includes superoxide production which functions in ferrireduction necessary for cell iron import. Activation of kinases and phosphatases and transcription factors and increased release of pro-inflammatory mediators also result from a cell iron deficiency, absolute or functional, after exposure to air pollutants. Finally, air pollutant exposure culminates in the development of inflammation and fibrosis which is a tissue response to the iron deficiency challenging cell survival. Following the response of increased expression of importers and ferrireduction, activation of kinases and phosphatases and transcription factors, release of pro-inflammatory mediators, and inflammation and fibrosis, cell iron is altered, and a new metal homeostasis is established. This new metal homeostasis includes increased total iron concentrations in cells with metal now at levels sufficient to meet requirements for continued function.
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Affiliation(s)
- Andrew J Ghio
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA.
| | - Joleen M Soukup
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA
| | - Lisa A Dailey
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA
| | - Michael C Madden
- From the National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill, NC, USA
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12
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Ali MK, Kim RY, Brown AC, Mayall JR, Karim R, Pinkerton JW, Liu G, Martin KL, Starkey MR, Pillar AL, Donovan C, Pathinayake PS, Carroll OR, Trinder D, Tay HL, Badi YE, Kermani NZ, Guo YK, Aryal R, Mumby S, Pavlidis S, Adcock IM, Weaver J, Xenaki D, Oliver BG, Holliday EG, Foster PS, Wark PA, Johnstone DM, Milward EA, Hansbro PM, Horvat JC. Crucial role for lung iron level and regulation in the pathogenesis and severity of asthma. Eur Respir J 2020; 55:13993003.01340-2019. [PMID: 32184317 DOI: 10.1183/13993003.01340-2019] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 01/28/2020] [Indexed: 01/08/2023]
Abstract
Accumulating evidence highlights links between iron regulation and respiratory disease. Here, we assessed the relationship between iron levels and regulatory responses in clinical and experimental asthma.We show that cell-free iron levels are reduced in the bronchoalveolar lavage (BAL) supernatant of severe or mild-moderate asthma patients and correlate with lower forced expiratory volume in 1 s (FEV1). Conversely, iron-loaded cell numbers were increased in BAL in these patients and with lower FEV1/forced vital capacity (FVC) ratio. The airway tissue expression of the iron sequestration molecules divalent metal transporter 1 (DMT1) and transferrin receptor 1 (TFR1) are increased in asthma, with TFR1 expression correlating with reduced lung function and increased Type-2 (T2) inflammatory responses in the airways. Furthermore, pulmonary iron levels are increased in a house dust mite (HDM)-induced model of experimental asthma in association with augmented Tfr1 expression in airway tissue, similar to human disease. We show that macrophages are the predominant source of increased Tfr1 and Tfr1+ macrophages have increased Il13 expression. We also show that increased iron levels induce increased pro-inflammatory cytokine and/or extracellular matrix (ECM) responses in human airway smooth muscle (ASM) cells and fibroblasts ex vivo and induce key features of asthma in vivo, including airway hyper-responsiveness (AHR) and fibrosis, and T2 inflammatory responses.Together these complementary clinical and experimental data highlight the importance of altered pulmonary iron levels and regulation in asthma, and the need for a greater focus on the role and potential therapeutic targeting of iron in the pathogenesis and severity of disease.
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Affiliation(s)
- Md Khadem Ali
- Division of Pulmonary and Critical Care Medicine, Stanford University, Stanford, CA, USA.,Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Richard Y Kim
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Centre for Inflammation, Centenary Institute and University of Technology Sydney, Sydney, Australia
| | - Alexandra C Brown
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Jemma R Mayall
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Rafia Karim
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - James W Pinkerton
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Respiratory Pharmacology and Toxicology Group, National Heart and Lung Institute, Imperial College London, London, UK
| | - Gang Liu
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Centre for Inflammation, Centenary Institute and University of Technology Sydney, Sydney, Australia
| | - Kristy L Martin
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Malcolm R Starkey
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Dept of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, Australia
| | - Amber L Pillar
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Chantal Donovan
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Centre for Inflammation, Centenary Institute and University of Technology Sydney, Sydney, Australia
| | - Prabuddha S Pathinayake
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Medicine and Public Health, University of Newcastle, Newcastle, Australia
| | - Olivia R Carroll
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Debbie Trinder
- Medical School, Harry Perkins Medical Research Institute, University of Western Australia, Fiona Stanley Hospital, Perth, Australia
| | - Hock L Tay
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Yusef E Badi
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, London, UK
| | - Nazanin Z Kermani
- Data Science Institute, Dept of Computing, Imperial College London, London, UK
| | - Yi-Ke Guo
- Data Science Institute, Dept of Computing, Imperial College London, London, UK
| | - Ritambhara Aryal
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Sharon Mumby
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, London, UK
| | - Stelios Pavlidis
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, London, UK
| | - Ian M Adcock
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, London, UK
| | - Jessica Weaver
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Dikaia Xenaki
- Woolcock Institute of Medical Research, University of Sydney and School of Life Sciences, University of Technology Sydney, Sydney, Australia
| | - Brian G Oliver
- Woolcock Institute of Medical Research, University of Sydney and School of Life Sciences, University of Technology Sydney, Sydney, Australia
| | - Elizabeth G Holliday
- Hunter Medical Research Institute, New Lambton, Australia.,School of Medicine and Public Health, University of Newcastle, Callaghan, Australia
| | - Paul S Foster
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Peter A Wark
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Dept of Respiratory and Sleep Medicine, John Hunter Hospital, Newcastle, Australia
| | - Daniel M Johnstone
- Discipline of Physiology and Bosch Institute, University of Sydney, Sydney, Australia
| | - Elizabeth A Milward
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Philip M Hansbro
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Centre for Inflammation, Centenary Institute and University of Technology Sydney, Sydney, Australia.,These authors contributed equally
| | - Jay C Horvat
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,These authors contributed equally
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13
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Huang L, Li L, Luo X, Huang S, Hou Q, Ge X, Lv Y, Mo Z, Yang X. The association between serum iron status and risk of asthma: a 2-sample Mendelian randomization study in descendants of Europeans. Am J Clin Nutr 2019; 110:959-968. [PMID: 31380560 DOI: 10.1093/ajcn/nqz162] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 06/27/2019] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Observational studies present conflicting results about a possible association of iron status with asthma risk, pointing to potential modifiable targets for prevention. OBJECTIVE The aim of this study was to use Mendelian randomization (MR) to estimate associations between iron status and asthma risk. METHODS We used the Genetics of Iron Status consortium to identify genetic variants that could be used as instrumental variables for the effect of systemic iron status. The following sets of instruments were used: a conservative set (instruments restricted to variants with concordant relations to 4 iron status biomarkers) and a liberal set (instruments selected using variants associated with at least 1 of 4 iron status biomarkers). Associations of these genetic variants with asthma risk were estimated in data from the Trans-National Asthma Genetics Consortium (TAGC) and the GABRIEL consortium (A Multidisciplinary Study to Identify the Genetic and Environmental Causes of Asthma in the European Community). Data on the association of genetic variants with iron status and with asthma were combined to assess the influence of iron status on asthma risk. RESULTS In the conservative approach, the MR OR of asthma was 1.00 (95% CI: 0.91, 1.10) per SD increase in iron, 0.96 (95% CI: 0.78, 1.18) in log-transformed ferritin, 0.99 (95% CI: 0.93, 1.06) in transferrin saturation, and 1.03 (95% CI: 0.93, 1.14) in transferrin in the TAGC dataset (none of the values were statistically significant). An age at onset-stratified analysis in the GABRIEL dataset suggested no effect of iron status in childhood onset, later onset, or unknown age at onset asthma. Findings from the liberal approach were similar, and the results persisted in sensitivity analyses (all P > 0.05). CONCLUSIONS This MR study does not provide evidence of an effect of iron status on asthma, suggesting that efforts to change iron concentrations will probably not result in decreased risk of asthma.
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Affiliation(s)
- Lulu Huang
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.,School of Nursing, Guangxi Medical University, Nanning, Guangxi, China
| | - Longman Li
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaoyu Luo
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Sifang Huang
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Qingzhi Hou
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaoting Ge
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Yingnan Lv
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Zengnan Mo
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaobo Yang
- Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.,Department of Occupational Health and Environmental Health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
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14
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Zinc and iron complexes of oleanolic acid, (OA) attenuate allergic airway inflammation in rats. Inflammopharmacology 2019; 27:1179-1192. [PMID: 31069605 DOI: 10.1007/s10787-019-00597-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 04/10/2019] [Indexed: 12/13/2022]
Abstract
Oleanolic acid (OA) is a hydroxyl pentacyclic triterpene acid (HTAs) used in various ailments. Inflammatory diseases may be profoundly influenced by iron (Fe) and zinc (Zn) status. We studied the anti-asthmatic effects of two metal complexes (Fe and Zn) of OA in the ovalbumin (OVA)-induced rat model. Delayed type hypersensitivity (DTH) was measured. Total and differential leucocyte count was done in blood as well as bronchoalveolar lavage fluid (BALF). The mRNA expression levels of pro-inflammatory cytokines were measured in lung tissue by reverse transcription polymerase chain reaction. The levels of cyclooxygenase-2 (COX-2), immunoglobulin E (IgE) and 5-lipoxygenase (5-LOX) were estimated by enzyme linked immunosorbent assay. Splenocyte proliferation was performed through BrdU uptake method and nitric oxide levels were measured by colorimetric assay kit. The acute toxicity study was also done for the complexes. The asthmatic group developed allergic airway inflammation shown by increased DTH and inflammatory markers in blood and BALF. OA + Fe and OA + Zn displayed significant decrease in DTH, NO, expression of IL-4, 5, 13, 17, toll-like receptor-2, nuclear factor-kappa B and tumor necrosis factor-α; serum IgE, COX-2, and 5-LOX. The metal complexes also attenuated OVA-stimulated splenocyte proliferation. While no hepatotoxic or nephrotoxic potential was shown by OA + Fe and OA + Zn. Our findings indicate that both OA + Fe and OA + Zn possess significant anti-asthmatic effect which may be ascribed to its immunomodulatory and anti-inflammatory features.
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15
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A Wearable Iron-Based Implant as an Intramedullary Nail in Tibial Shaft Fracture of Sheep. Int J Biomater 2019; 2019:8798351. [PMID: 30941179 PMCID: PMC6420965 DOI: 10.1155/2019/8798351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 12/25/2018] [Accepted: 01/28/2019] [Indexed: 12/22/2022] Open
Abstract
A stable repaired fracture is the key factor responsible for the recovery of a damaged bone. The iron-based implant is one of the biodegradable metals that have been proven safe as a fracture fixation device. The objective of our experimental approach was to examine the potential of the iron-based implant as a biodegradable metal in tibia shaft fracture in sheep chronically. The samples used for this experiment were iron-based and stainless steel implants. Each had a diameter of 5 mm. These samples were analyzed through 3 phases which are material characterization, in vitro and in vivo examination. The samples were examined using a scanning electron microscope with energy dispersive spectrometer and X-ray diffraction. Based on the analysis carried out, the samples contained 90,02% and 60,81% Fe for iron-based implant and stainless implant, respectively. Both implants maintained high viability when being in contact with calf pulmonary artery endothelial cells, indicating that both implants had a minimum response to the cell in a hemocytometer and methyl tetrazolium (MTT) assay. The systemic effect of the implants was observed using hematology and blood chemistry examination. Data collection also shows that both implants also had a minimum response to the erythrocytes, leucocytes, blood chemistry, and blood mineral during the period of observation. Therefore, it could be concluded that the iron-based implant is tolerable for a period of 9 months. It also has the potential to be used as a biodegradable orthopedic implant.
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16
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Roth-Walter F, Pacios LF, Bianchini R, Jensen-Jarolim E. Linking iron-deficiency with allergy: role of molecular allergens and the microbiome. Metallomics 2017; 9:1676-1692. [PMID: 29120476 DOI: 10.1039/c7mt00241f] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Atopic individuals tend to develop a Th2 dominant immune response, resulting in hyperresponsiveness to harmless antigens, termed allergens. In the last decade, epidemiological studies have emerged that connected allergy with a deficient iron-status. Immune activation under iron-deficient conditions results in the expansion of Th2-, but not Th1 cells, can induce class-switching in B-cells and hampers the proper activation of M2, but not M1 macrophages. Moreover, many allergens, in particular with the lipocalin and lipocalin-like folds, seem to be capable of binding iron indirectly via siderophores harboring catechol moieties. The resulting locally restricted iron-deficiency may then lead during immune activation to the generation of Th2-cells and thus prepare for allergic sensitization. Moreover, iron-chelators seem to also influence clinical reactivity: mast cells accumulate iron before degranulation and seem to respond differently depending on the type of the encountered siderophore. Whereas deferoxamine triggers degranulation of connective tissue-type mast cells, catechol-based siderophores reduce activation and degranulation and improve clinical symptoms. Considering the complex interplay of iron, siderophores and immune molecules, it remains to be determined whether iron-deficiencies are the cause or the result of allergy.
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Affiliation(s)
- Franziska Roth-Walter
- Department of Comparative Medicine, at the Interuniversity Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna and University of Vienna, Vienna, Austria.
| | - Luis F Pacios
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA), Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo-UPM, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Rodolfo Bianchini
- Department of Comparative Medicine, at the Interuniversity Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna and University of Vienna, Vienna, Austria.
| | - Erika Jensen-Jarolim
- Department of Comparative Medicine, at the Interuniversity Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna and University of Vienna, Vienna, Austria. and Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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17
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Shaheen SO, Macdonald-Wallis C, Lawlor DA, Henderson AJ. Haemoglobin concentrations in pregnancy and respiratory and allergic outcomes in childhood: Birth cohort study. Clin Exp Allergy 2017; 47:1615-1624. [PMID: 28940397 PMCID: PMC5725736 DOI: 10.1111/cea.13034] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/31/2017] [Accepted: 09/12/2017] [Indexed: 12/23/2022]
Abstract
Background Limited epidemiological evidence suggests that low maternal iron status and anaemia in pregnancy may increase the risk of childhood respiratory and allergic outcomes. Objectives To investigate the relation between maternal haemoglobin concentrations in pregnancy and childhood respiratory and allergic outcomes. Methods In the Avon Longitudinal Study of Parents and Children (ALSPAC), we examined associations of maternal haemoglobin concentrations (g/dL) in pregnancy with hayfever, eczema, wheezing, doctor‐diagnosed asthma, allergic sensitisation and total IgE at 7 years, and with lung function at 8‐9 years in the offspring, after controlling for potential confounders (N = 3234‐5335). Results Maternal haemoglobin was not associated with offspring hayfever, eczema, wheezing or asthma. However, the first haemoglobin measurement in pregnancy (<18 weeks' gestation) and the last measurement (>28 weeks' gestation) were negatively associated with allergic sensitisation (adjusted odds ratio [95% CI] per g/dL 0.91 [0.83 to 0.99] and 0.90 [0.83 to 0.98], respectively). The last haemoglobin measurement was also negatively associated with total IgE (adjusted geometric mean ratio 0.94 [0.88 to 0.99]). Anaemia (haemoglobin <11 g/dL) in late pregnancy was negatively associated with forced vital capacity (difference in standard deviation score −0.07 [−0.13 to −0.01]). Conclusions and Clinical Relevance Lower maternal haemoglobin in pregnancy may be a risk factor for allergic sensitisation, elevated IgE and lower FVC in childhood, which may reflect effects of lower prenatal iron status. However, maternal haemoglobin was not associated with risk of childhood asthma or other allergic disorders.
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Affiliation(s)
- S O Shaheen
- Centre for Primary Care and Public Health, Barts and The London School of Medicine and Dentistry, London, UK
| | - C Macdonald-Wallis
- School of Social and Community Medicine, University of Bristol, Bristol, UK.,MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
| | - D A Lawlor
- School of Social and Community Medicine, University of Bristol, Bristol, UK.,MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
| | - A J Henderson
- School of Social and Community Medicine, University of Bristol, Bristol, UK
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18
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Ali MK, Kim RY, Karim R, Mayall JR, Martin KL, Shahandeh A, Abbasian F, Starkey MR, Loustaud-Ratti V, Johnstone D, Milward EA, Hansbro PM, Horvat JC. Role of iron in the pathogenesis of respiratory disease. Int J Biochem Cell Biol 2017; 88:181-195. [PMID: 28495571 DOI: 10.1016/j.biocel.2017.05.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 05/01/2017] [Accepted: 05/03/2017] [Indexed: 12/13/2022]
Abstract
Iron is essential for many biological processes, however, too much or too little iron can result in a wide variety of pathological consequences, depending on the organ system, tissue or cell type affected. In order to reduce pathogenesis, iron levels are tightly controlled in throughout the body by regulatory systems that control iron absorption, systemic transport and cellular uptake and storage. Altered iron levels and/or dysregulated homeostasis have been associated with several lung diseases, including chronic obstructive pulmonary disease, lung cancer, cystic fibrosis, idiopathic pulmonary fibrosis and asthma. However, the mechanisms that underpin these associations and whether iron plays a key role in the pathogenesis of lung disease are yet to be fully elucidated. Furthermore, in order to survive and replicate, pathogenic micro-organisms have evolved strategies to source host iron, including freeing iron from cells and proteins that store and transport iron. To counter these microbial strategies, mammals have evolved immune-mediated defence mechanisms that reduce iron availability to pathogens. This interplay between iron, infection and immunity has important ramifications for the pathogenesis and management of human respiratory infections and diseases. An increased understanding of the role that iron plays in the pathogenesis of lung disease and respiratory infections may help inform novel therapeutic strategies. Here we review the clinical and experimental evidence that highlights the potential importance of iron in respiratory diseases and infections.
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Affiliation(s)
- Md Khadem Ali
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Richard Y Kim
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Rafia Karim
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Jemma R Mayall
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Kristy L Martin
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Ali Shahandeh
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Firouz Abbasian
- Global Centre for Environmental Remediation, Faculty of Science, the University of Newcastle, Callaghan, NSW 2308, Australia
| | - Malcolm R Starkey
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | | | - Daniel Johnstone
- Bosch Institute and Discipline of Physiology, The University of Sydney, Sydney NSW 2000, Australia
| | - Elizabeth A Milward
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Philip M Hansbro
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Jay C Horvat
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia.
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19
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Asthma as a disruption in iron homeostasis. Biometals 2016; 29:751-79. [PMID: 27595579 DOI: 10.1007/s10534-016-9948-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 07/07/2016] [Indexed: 12/28/2022]
Abstract
Over several decades, asthma has evolved from being recognized as a single disease to include a diverse group of phenotypes with dissimilar natural histories, pathophysiologies, responses to treatment, and distinctive molecular pathways. With the application of Occam's razor to asthma, it is proposed that there is one cause underlying the numerous phenotypes of this disease and that the responsible molecular pathway is a deficiency of iron in the lung tissues. This deficiency can be either absolute (e.g. asthma in the neonate and during both pregnancy and menstruation) or functional (e.g. asthma associated with infections, smoking, and obesity). Comparable associations between asthma co-morbidity (e.g. eczema, urticaria, restless leg syndrome, and pulmonary hypertension) with iron deficiency support such a shared mechanistic pathway. Therapies directed at asthma demonstrate a capacity to impact iron homeostasis, further strengthening the relationship. Finally, pathophysiologic events producing asthma, including inflammation, increases in Th2 cells, and muscle contraction, can correlate with iron availability. Recognition of a potential association between asthma and an absolute and/or functional iron deficiency suggests specific therapeutic interventions including inhaled iron.
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20
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Syed A, Bhandari S. Correction of iron deficiency anaemia using IV CosmoFer in CKD patients with asthma: a prospective study. QJM 2016; 109:187-90. [PMID: 26101227 DOI: 10.1093/qjmed/hcv117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Intravenous (IV) iron is commonly used for correcting iron deficiency anaemia in patients with chronic kidney disease (CKD). There remains a concern for its use in patients with asthma as it may trigger an acute exacerbation. Pre-treatment with a single dose of parenteral hydrocortisone may obviate this risk. METHOD We carried out a prospective study of known asthmatic patients with CKD requiring single-dose iron repletion therapy. We analysed the efficacy and safety of IV CosmoFer (low molecular weight iron dextran). Twenty non-dialysis CKD patients with iron deficiency anaemia and a history of asthma were enrolled. Severity of asthma and level of control were recorded as per British Thoracic Society Guidelines and Royal Collage of Physician questionnaire, respectively. All patients received IV hydrocortisone 30 min before the test dose of CosmoFer followed by the remaining total dose. Patients were monitored for adverse reactions. Haemoglobin, serum ferritin levels and estimated glomerular filtration rate were measured pre and 6-weeks post-infusion. All patients were followed up until 6 weeks to assess the control of their asthma. RESULTS All 20 patients completed the study. No patient experienced acute hypersensitivity or infusion reactions. At 6 weeks follow-up, no patient reported worsening of their asthma. There was an increase in mean haemoglobin from 10.1 to 11.1 g/dl and mean ferritin from 93.5 to 302.6 ng/ml. CONCLUSIONS This study demonstrates that IV CosmoFer may be administered safely in asthmatics by administering a single 50 mg dose of hydrocortisone pre-infusion.
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Affiliation(s)
- A Syed
- From the Department of Renal Medicine, Bradford Teaching Hospital NHS Foundation Trust, Duckworth lane, Bradford BD9 6RJ, UK and
| | - S Bhandari
- Department of Renal Medicine, Hull and East Yorkshire Hospitals NHS Trust and Hull York Medical School, Anlaby Road, Kingston-upon-Hull HU3 2JZ, UK
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Brigham EP, McCormack MC, Takemoto CM, Matsui EC. Iron status is associated with asthma and lung function in US women. PLoS One 2015; 10:e0117545. [PMID: 25689633 PMCID: PMC4331366 DOI: 10.1371/journal.pone.0117545] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 12/28/2014] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Asthma and iron deficiency are common conditions. Whether iron status affects the risk of asthma is unclear. OBJECTIVE To determine the relationship between iron status and asthma, lung function, and pulmonary inflammation. METHODS Relationships between measures of iron status (serum ferritin, serum soluble transferrin receptor (sTfR), and sTfR/log10ferritin (sTfR-F Index)) and asthma, lung function, and pulmonary inflammation were examined in women 20-49 years in the National Health and Nutrition Examination Survey. Logistic, linear, and quadratic regression models accounting for the survey design of NHANES were used to evaluate associations between iron status and asthma-related outcomes and were adjusted for race/ethnicity, age, smoking status, income, and BMI. RESULTS Approximately 16% reported a lifetime history of asthma, 9% reported current asthma, and 5% reported a recent asthma episode/attack (n = 2906). Increased ferritin (iron stores) was associated with decreased odds of lifetime asthma, current asthma, and asthma attacks/episodes in the range of ferritin linearly correlated with iron stores (20-300ng/ml). The highest quintile of ferritin (>76 ng/ml) was also associated with a decreased odds of asthma. Ferritin levels were not associated with FEV1. Increased values of the sTfR-F Index and sTfR, indicating lower body iron and higher tissue iron need, respectively, were associated with decreased FEV1, but neither was associated with asthma. None of the iron indices were associated with FeNO. CONCLUSION In US women, higher iron stores were inversely associated with asthma and lower body iron and higher tissue iron need were associated with lower lung function. Together, these findings suggest that iron status may play a role in asthma and lung function in US women.
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Affiliation(s)
- Emily P. Brigham
- Johns Hopkins University School of Medicine, Division of Pulmonary and Critical Care Medicine, Baltimore, Maryland, United States of America
| | - Meredith C. McCormack
- Johns Hopkins University School of Medicine, Division of Pulmonary and Critical Care Medicine, Baltimore, Maryland, United States of America
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Clifford M. Takemoto
- Johns Hopkins University School of Medicine, Division of Pediatric Hematology, Baltimore, Maryland, United States of America
| | - Elizabeth C. Matsui
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins University School of Medicine, Division of Pediatric Allergy and Immunology, Baltimore, Maryland, United States of America
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An exploratory study of the associations between maternal iron status in pregnancy and childhood wheeze and atopy. Br J Nutr 2014; 112:2018-27. [PMID: 25342229 DOI: 10.1017/s0007114514003122] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Maternal nutritional status during pregnancy has been reported to be associated with childhood asthma and atopic disease. The Avon Longitudinal Study of Parents and Children has reported associations between reduced umbilical cord Fe status and childhood wheeze and eczema; however, follow-up was short and lung function was not measured. In the present study, the associations between maternal Fe status during pregnancy and childhood outcomes in the first 10 years of life were investigated in a subgroup of 157 mother-child pairs from a birth cohort with complete maternal, fetal ultrasound, blood and child follow-up data. Maternal Fe intake was assessed using FFQ at 32 weeks of gestation and Hb concentrations and serum Fe status (ferritin, soluble transferrin receptor and TfR-F (transferrin receptor:ferritin) index) were measured at 11 weeks of gestation and at delivery. Maternal Fe intake, Hb concentrations and serum Fe status were found to be not associated with fetal or birth measurements. Unit increases in first-trimester maternal serum TfR concentrations (OR 1.44, 95% CI 1.05, 1.99) and TfR-F index (OR 1.42, 95% CI 1.10, 1.82) (i.e. decreasing Fe status) were found to be associated with an increased risk of wheeze, while unit increases in serum ferritin concentrations (i.e., increasing Fe status) were found to be associated with increases in standardised mean peak expiratory flow (PEF) (β 0.25, 95% CI 0.09, 0.42) and forced expiratory volume in the first second (FEV1) (β 0.20, 95% CI 0.08, 0.32) up to 10 years of age. Increasing maternal serum TfR-F index at delivery was found to be associated with an increased risk of atopic sensitisation (OR 1.35, 95% CI 1.02, 1.79). The results of the present study suggest that reduced maternal Fe status during pregnancy is adversely associated with childhood wheeze, lung function and atopic sensitisation, justifying further studies on maternal Fe status and childhood asthma and atopic disease.
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Ghio AJ, Soukup JM, Dailey LA, Richards JH, Duncan KE, Lehmann J. Iron decreases biological effects of ozone exposure. Inhal Toxicol 2014; 26:391-9. [DOI: 10.3109/08958378.2014.908330] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Maazi H, Shirinbak S, den Boef LE, Fallarino F, Volpi C, Nawijn MC, van Oosterhout AJM. Cytotoxic T lymphocyte antigen 4-immunoglobulin G is a potent adjuvant for experimental allergen immunotherapy. Clin Exp Immunol 2013; 172:113-20. [PMID: 23480191 DOI: 10.1111/cei.12041] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2012] [Indexed: 01/21/2023] Open
Abstract
Allergen-specific immunotherapy (SIT) is the only treatment for allergic diseases that targets allergen-specific T helper type 2 (Th2) cells, which are the cause of the disease. There is an unmet requirement for adjuvants that increase the clinical efficacy of SIT allowing application of lower doses of the allergen, thereby reducing the risk of anaphylactic reactions. Cytotoxic T lymphocyte antigen 4-immunoglobulin (CTLA-4-Ig) has been shown to induce immunological tolerance in autoimmunity and allograft transplantation by blocking T cell co-stimulation and induction of the immunoregulatory enzyme indoleamine 2,3 dioxygenase (IDO). Previously, we showed that CTLA-4-Ig treatment at the time of allergen inhalation induced tolerance to subsequent allergen exposure in a mouse model of asthma. In this study, we test the hypothesis that CTLA-4-Ig acts as an adjuvant for experimental SIT. We evaluated the adjuvant effects of CTLA-4-Ig on SIT in a mouse model of ovalbumin-driven asthma. We used both wild-type and IDO-deficient mice to assess the role of IDO in the adjuvant effects of CTLA-4-Ig. Co-administration of CTLA-4-Ig strongly increased SIT-induced suppression of airway hyperreactivity (AHR), specific IgE in serum, airway eosinophilia and Th2 cytokine levels. Moreover, we found that CTLA-4-Ig, as an adjuvant for SIT, is equally effective in IDO-deficient and wild-type mice, demonstrating that the effect of CTLA-4-Ig is independent of IDO expression. We show that CTLA-4-Ig acts as a potent adjuvant to augment the therapeutic effects of SIT. As the adjuvant activity of CTLA-4-Ig is independent of IDO, we conclude that it acts by blocking CD28-mediated T cell co-stimulation.
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Affiliation(s)
- H Maazi
- Laboratory of Allergology and Pulmonary Diseases, Department of Pathology and Medical Biology, University Medical Center Groningen (UMCG), GRIAC Research Institute, University of Groningen, Groningen, the Netherlands
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Iron supplementation decreases severity of allergic inflammation in murine lung. PLoS One 2012; 7:e45667. [PMID: 23029172 PMCID: PMC3447873 DOI: 10.1371/journal.pone.0045667] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 08/21/2012] [Indexed: 02/07/2023] Open
Abstract
The incidence and severity of allergic asthma have increased over the last century, particularly in the United States and other developed countries. This time frame was characterized by marked environmental changes, including enhanced hygiene, decreased pathogen exposure, increased exposure to inhaled pollutants, and changes in diet. Although iron is well-known to participate in critical biologic processes such as oxygen transport, energy generation, and host defense, iron deficiency remains common in the United States and world-wide. The purpose of these studies was to determine how dietary iron supplementation affected the severity of allergic inflammation in the lungs, using a classic model of IgE-mediated allergy in mice. Results showed that mice fed an iron-supplemented diet had markedly decreased allergen-induced airway hyperreactivity, eosinophil infiltration, and production of pro-inflammatory cytokines, compared with control mice on an unsupplemented diet that generated mild iron deficiency but not anemia. In vitro, iron supplementation decreased mast cell granule content, IgE-triggered degranulation, and production of pro-inflammatory cytokines post-degranulation. Taken together, these studies show that iron supplementation can decrease the severity of allergic inflammation in the lung, potentially via multiple mechanisms that affect mast cell activity. Further studies are indicated to determine the potential of iron supplementation to modulate the clinical severity of allergic diseases in humans.
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