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El-Amawy HS, Dawoud H. Lysosomal storage diseases in the era of COVID-19: a report of an Egyptian case of alpha-fucosidosis and a summary of the lysosomal storage diseases-COVID-19 relationship. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2022; 23:138. [PMID: 37521839 PMCID: PMC9483389 DOI: 10.1186/s43042-022-00350-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 09/08/2022] [Indexed: 11/30/2022] Open
Abstract
Background We present a case of alpha-fucosidosis, a lysosomal storage disorder, from Egypt. The report also includes a brief review of the COVID-19 and lysosomal storage diseases relationship. Case presentation A female patient aged 18 years, diagnosed with type II fucosidosis, based on the cutaneous signs, characteristic facies, and systemic symptoms, and diagnosis was confirmed using genetic analysis. The patient died from COVID-19 pneumonia during the COVID-19 pandemic after getting the infection from her father and being hospitalized. Conclusions Patients with lysosomal storage diseases with local or systemic immune suppression may be predisposed to respiratory complications of COVID-19. Intense care with protective guidelines should be applied to those patients.
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Affiliation(s)
| | - Heba Dawoud
- Faculty of Medicine, Tanta University, Tanta, Egypt
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2
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Liang EY, Li GH, Wang WG, Qiu XM, Ke PF, He M, Huang XZ. Clinical relevance of serum α-l-fucosidase activity in the SARS-CoV-2 infection. Clin Chim Acta 2021; 519:26-31. [PMID: 33826953 PMCID: PMC8019593 DOI: 10.1016/j.cca.2021.03.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/24/2021] [Accepted: 03/31/2021] [Indexed: 11/18/2022]
Abstract
Background and aims The reduced fucosylation in the spike glycoprotein of SARS-CoV-2 and the IgG antibody has been observed in COVID-19. However, the clinical relevance of α-l-fucosidase, the enzyme for defucosylation has not been discovered. Materials and methods 585 COVID-19 patients were included to analyze the correlations of α-l-fucosidase activity with the nucleic acid test, IgM/IgG, comorbidities, and disease progression. Results Among the COVID-19 patients, 5.75% were double-negative for nucleic acid and antibodies. All of them had increased α-l-fucosidase, while only one had abnormal serum amyloid A (SAA) and C-reactive protein (CRP). The abnormal rate of α-l-fucosidase was 81.82% before the presence of IgM, 100% in the presence of IgM, and 66.2% in the presence of IgG. 73.42% of patients with glucometabolic disorders had increased α-l-fucosidase activity and had the highest mortality of 6.33%. The increased α-l-fucosidase was observed in 55.8% of non-severe cases and 72.9% of severe cases, with an odds ratio of 2.118. The α-l-fucosidase mRNA was irrelevant to its serum activity. Conclusion The change in α-l-fucosidase activity in COVID-19 preceded the IgM and SAA and showed a preferable relation with glucometabolic disorders, which may be conducive to virus invasion or invoke an immune response against SARS-CoV-2.
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Affiliation(s)
- En-Yu Liang
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Guo-Hua Li
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China; Hubei Integrated Traditional Chinese and Western Medicine Hospital, Wuhan 430015, China
| | - Wen-Gong Wang
- Hubei Integrated Traditional Chinese and Western Medicine Hospital, Wuhan 430015, China
| | - Xin-Min Qiu
- Genetic Testing Lab, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Pei-Feng Ke
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Min He
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China; Guangdong Provincial Key Laboratory of Research on Emergency in TCM, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China.
| | - Xian-Zhang Huang
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China; Guangdong Provincial Key Laboratory of Research on Emergency in TCM, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China.
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3
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Fucosidosis-Clinical Manifestation, Long-Term Outcomes, and Genetic Profile-Review and Case Series. Genes (Basel) 2020; 11:genes11111383. [PMID: 33266441 PMCID: PMC7700486 DOI: 10.3390/genes11111383] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/10/2020] [Accepted: 11/19/2020] [Indexed: 12/21/2022] Open
Abstract
Fucosidosis is a neurodegenerative disorder which progresses inexorably. Clinical features include coarse facial features, growth retardation, recurrent upper respiratory infections, dysostosis multiplex, and angiokeratoma corporis diffusum. Fucosidosis is caused by mutations in the FUCA1 gene resulting in α-L-fucosidase deficiency. Only 36 pathogenic variants in the FUCA1 gene are related to fucosidosis. Most of them are missense/nonsense substitutions; six missense and 11 nonsense mutations. Among deletions there were eight small and five gross changes. So far, only three splice site variants have been described—one small deletion, one complete deletion and one stop-loss mutation. The disease has a significant clinical variability, the cause of which is not well understood. The genotype–phenotype correlation has not been well defined. This review describes the genetic profile and clinical manifestations of fucosidosis in pediatric and adult cases.
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Carpenter J, Lynch SE, Cribb JA, Kylstra S, Hill DB, Superfine R. Buffer drains and mucus is transported upward in a tilted mucus clearance assay. Am J Physiol Lung Cell Mol Physiol 2018; 315:L910-L918. [PMID: 30211652 DOI: 10.1152/ajplung.00274.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Mucociliary clearance (MCC) plays an essential role in maintaining airway sterility and health. Conversely, mucociliary dysfunction is implicated across many airway obstructive diseases. Understanding the necessary requirements for successful MCC is imperative to establish the pathology of disease, as well as to develop therapeutic strategies. Although postural, that is, gravitational, drainage is used clinically to aid mucus clearance, it is ignored in both animal and cell culture models of MCC. In this study, we develop a novel mucus clearance assay that enables the first particle image velocimetry of human bronchial epithelial cell cultures tilted relative to the gravitational field. This tilting system makes it possible to observe drainage of the airway surface liquid and, thus, reveals the effect gravity has on mucociliary clearance. First, we use this assay to demonstrate that beating cilia alone cannot transport buffer upward against gravity. Next, we show the same cilia successfully transporting mucus upward. These results indicate that the biophysical and biochemical properties of mucus enable vertical clearance and that current assay systems are not equipped to determine which properties are required for physiologically relevant vertical mucociliary clearance.
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Affiliation(s)
- Jerome Carpenter
- Department of Pathology and Laboratory Medicine, The University of North Carolina , Chapel Hill, North Carolina.,Marsico Lung Institute, The University of North Carolina , Chapel Hill, North Carolina
| | - Suzanne E Lynch
- Department of Biochemistry and Biophysics, The University of North Carolina , Chapel Hill, North Carolina
| | - Jeremy A Cribb
- Department of Physics and Astronomy, The University of North Carolina , Chapel Hill, North Carolina
| | - Schuyler Kylstra
- Department of Physics and Astronomy, The University of North Carolina , Chapel Hill, North Carolina
| | - David B Hill
- Marsico Lung Institute, The University of North Carolina , Chapel Hill, North Carolina.,Department of Physics and Astronomy, The University of North Carolina , Chapel Hill, North Carolina
| | - Richard Superfine
- Department of Applied Physical Sciences, The University of North Carolina , Chapel Hill, North Carolina
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Guglani L, Moir D, Jain A. Sweat chloride concentrations in children with Idiopathic Nephrotic Syndrome. Pediatr Pulmonol 2016; 51:49-52. [PMID: 26309139 DOI: 10.1002/ppul.23213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 02/14/2015] [Accepted: 03/30/2015] [Indexed: 11/07/2022]
Abstract
BACKGROUND Idiopathic Nephrotic Syndrome (INS) has been believed to cause a false positive elevation of sweat chloride concentrations, as measured by the sweat test. METHODS Sweat tests were done for 11 children with acute onset INS at admission and again while they were in remission, with results being compared to normal historical controls. RESULTS The initial sweat chloride concentration for 10 patients was normal (mean16.7 ± 11.02 mmol/L) and 1 patient had inadequate collection. This latter patient and two others were excluded during follow-up because of diagnoses other than INS. Sweat test results for the eight INS patients during follow up remained unchanged when they were in remission (16.94 ± 7.88 mmol/L; P = 0.98; Wilcoxon Matched-Pairs Signed Rank Test). In comparing sweat chloride concentrations from INS patients to those from 20 historical control subjects, we found no significant differences (Mann-Whitney Test; initial vs. control P = 0.643; follow up vs. control P = 0.806). CONCLUSIONS INS does not cause a false positive sweat test. Further studies should be done to objectively assess the conditions that have been reported to affect sweat chloride concentrations.
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Affiliation(s)
- Lokesh Guglani
- Carman and Ann Adams Department of Pediatrics, Division of Pediatric Pulmonology, Wayne State University School of Medicine, Children's Hospital of Michigan, Detroit, Michigan
| | - Devin Moir
- Carman and Ann Adams Department of Pediatrics, Division of Pediatric Pulmonology, Wayne State University School of Medicine, Children's Hospital of Michigan, Detroit, Michigan
| | - Amrish Jain
- Carman and Ann Adams Department of Pediatrics, Division of Pediatric Nephrology, Wayne State University School of Medicine, Children's Hospital of Michigan, Detroit, Michigan
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Guglani L, Stabel D, Weiner DJ. False-Positive and False-Negative Sweat Tests: Systematic Review of the Evidence. PEDIATRIC ALLERGY IMMUNOLOGY AND PULMONOLOGY 2015; 28:198-211. [DOI: 10.1089/ped.2015.0552] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Lokesh Guglani
- Division of Pulmonology Allergy/Immunology Cystic Fibrosis & Sleep (PACS), Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, CA
| | - Danelle Stabel
- Division of General Pediatrics, Department of Pediatrics, Children's Hospital of Michigan, Detroit, Michigan
| | - Daniel J. Weiner
- Division of Allergy, Immunology and Pulmonology, Department of Pediatrics, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania
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Secretion properties, clearance, and therapy in airway disease. TRANSLATIONAL RESPIRATORY MEDICINE 2014; 2:6. [PMID: 25505698 PMCID: PMC4215824 DOI: 10.1186/2213-0802-2-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 02/19/2014] [Indexed: 01/26/2023]
Abstract
Chronic airway diseases like cystic fibrosis, chronic bronchitis, asthma, diffuse panbronchiolitis, and bronchiectasis are all associated with chronic inflammation. The airway mucosa responds to infection and inflammation in part by surface mucous (goblet) cell and submucosal gland hyperplasia and hypertrophy with mucus hypersecretion. Products of inflammation including neutrophil derived DNA and filamentous actin, effete cells, bacteria, and cell debris all contribute to mucus purulence and, when this is expectorated it is called sputum. Mucus is usually cleared by ciliary movement, and sputum is cleared by cough. These airway diseases each are associated with the production of mucus and sputum with characteristic composition, polymer structure, and biophysical properties. These properties change with the progress of the disease making it possible to use sputum analysis to identify the potential cause and severity of airway diseases. This information has also been important for the development of effective mucoactive therapy to promote airway hygiene.
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Sobkowicz AD, Gallagher ME, Reid CJ, Crean D, Carrington SD, Irwin JA. Modulation of expression in BEAS-2B airway epithelial cells of α-L-fucosidase A1 and A2 by Th1 and Th2 cytokines, and overexpression of α-L-fucosidase 2. Mol Cell Biochem 2014; 390:101-13. [PMID: 24469468 DOI: 10.1007/s11010-014-1961-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 01/14/2014] [Indexed: 01/27/2023]
Abstract
Chronic Th2-driven airway inflammation with excessive mucus production occurs in asthma. The regulation of FUCA1 and FUCA2 gene expression and enzyme activity in response to asthma-associated Th2 cytokines and, for contrast, Th1 cytokine IFN-γ, were investigated in a human airway cell line. BEAS-2B cells were supplemented with Th2-derived cytokines (IL-13, IL-4, IL-5) or/and IFN-γ. RNA and cell supernatants from stimulated and unstimulated cells were collected over a period of 3 h. Alpha-L-fucosidase A1 and A2 gene expression were assessed using real time RT-PCR, while enzymatic activities were measured using a fluorescent assay. To characterise α-L-fucosidase A2, CHO-K1 and BEAS-2B cell lines were transiently transfected, the FUCA2 gene was overexpressed, and the protein was immunoprecipitated. The transcription of FUCA1 was upregulated (p < 0.01) in response to IFN-γ, suggesting that FUCA1 transcription and fucosidase activity are regulated in a Th1-dependent manner. The gene expression was the highest for 30 min after IFN-γ stimulation (>twofold induction), whereas secreted enzyme activity in BEAS-2B cells was significantly increased 1 h after IFN-γ addition. IL-4, IL-5 and IL-13 had no effect on FUCA1 and FUCA2 expression and activity. The IFN-γ-induced increase in expression and activity was repressed by the presence of the Th2 cytokine IL-5. Enzymatically active α-L-fucosidase 2 was immunoprecipitated from BEAS-2B cells, with highest activity at pH 4.9. IL-13, IL-4 and IL-5 have no effect on the expression of FUCA1 and FUCA2, but its expression is upregulated by IFN-γ, a Th1 cytokine. Active α-L-fucosidase 2 was overexpressed in BEAS-2B cells.
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Affiliation(s)
- Anna D Sobkowicz
- Veterinary Sciences Centre, School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
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Guglani L, Sitwat B, Lower D, Kurland G, Weiner DJ. Elevated sweat chloride concentration in children without cystic fibrosis who are receiving topiramate therapy. Pediatr Pulmonol 2012; 47:429-33. [PMID: 22081517 DOI: 10.1002/ppul.21563] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 09/03/2011] [Indexed: 12/22/2022]
Abstract
BACKGROUND Topiramate, which is used as an anticonvulsant and for migraine prophylaxis in children, causes oligohydrosis as a side-effect, but its effect on sweat chloride concentrations has not been studied systematically. METHODS Twenty-one children receiving topiramate and 20 healthy controls with no signs or symptoms of pulmonary or gastrointestinal disease and a negative family history for cystic fibrosis (CF) underwent bilateral pilocarpine iontophoresis and sweat collection via Macroduct® system. RESULTS Adequate samples (>15 µl volume) were obtained from 17/19 topiramate subjects (89%), and 19/20 (95%) controls. The mean sweat chloride concentration was 37.7 ± 18.8 mmol/L for patients receiving topiramate, and 15.9 ± 6.9 mmol/L for controls (p = 0.0001). The mean sweat volume was 29.1 ± 17.4 µl for patients receiving topiramate, and 41.2 ± 17.5 µl for controls (p = 0.037). Overall 8/17 (47%) of patients on topiramate with a measurable sweat chloride had either an intermediate (>40 mmol/L but <60 mmol/L) or elevated (>60 mmol/L) sweat chloride test result, while 0/19 control subjects had elevated sweat chloride (p = 0.0008). Further analysis of the in vitro activity of topiramate on cultured human bronchial epithelial cells in modified Ussing chambers showed no differences in chloride conductance measured in cells exposed to 10 or 50 µg/ml of topiramate when compared to non-exposed cells. CONCLUSIONS This is the first report of a medication affecting sweat chloride values and shows that topiramate therapy can cause elevated sweat chloride concentrations in the absence of clinical manifestations of CF.
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Affiliation(s)
- Lokesh Guglani
- Division of Pediatric Pulmonology, Department of Pediatrics, Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
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10
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Chen EY, Daley D, Wang YC, Garnica M, Chen CS, Chin WC. Functionalized carboxyl nanoparticles enhance mucus dispersion and hydration. Sci Rep 2012; 2:211. [PMID: 22355725 PMCID: PMC3251626 DOI: 10.1038/srep00211] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 12/14/2011] [Indexed: 11/09/2022] Open
Abstract
Luminal accumulation of viscous, poorly hydrated, and less transportable mucus has been associated with altered mucus rheology and reduced mucociliary clearance. These symptoms are some of the cardinal clinical manifestations found throughout major respiratory diseases as well as gastrointestinal and digestive disorders. Applications of current mucolytics may yield short-term improvements but are continuously challenged by undesirable side-effects. While nanoparticles (NPs) can interact with mucin polymers,whether functionalized NPs can rectify mucus rheology is unknown. Herein, we report that carboxyl-functionalized NPs (24 nm and 120 nm) dramatically reduced mucin gel size and accelerated mucin matrix hydration rate (diffusivity). Our results suggest that carboxyl-functionalized NPs disperse mucin gels possibly by enhancing network hydration. This report highlights the prospective usages of carboxyl-functionalized NPs as a novel mucus dispersant or mucolytic agent in adjusting mucus rheological properties and improving mucociliary transport to relieve clinical symptoms of patients suffering from relevant diseases.
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Affiliation(s)
- Eric Y. Chen
- Bioengineering, University of California Merced, CA 95343, USA. 5200 North Lake Road, Merced, CA 95343, USA
| | - David Daley
- Bioengineering, University of California Merced, CA 95343, USA. 5200 North Lake Road, Merced, CA 95343, USA
| | - Yung-Chen Wang
- Bioengineering, University of California Merced, CA 95343, USA. 5200 North Lake Road, Merced, CA 95343, USA
| | - Maria Garnica
- Bioengineering, University of California Merced, CA 95343, USA. 5200 North Lake Road, Merced, CA 95343, USA
| | - Chi-Shuo Chen
- Bioengineering, University of California Merced, CA 95343, USA. 5200 North Lake Road, Merced, CA 95343, USA
| | - Wei-Chun Chin
- Bioengineering, University of California Merced, CA 95343, USA. 5200 North Lake Road, Merced, CA 95343, USA
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Taylor CJ, Hardcastle J, Southern KW. Physiological measurements confirming the diagnosis of cystic fibrosis: the sweat test and measurements of transepithelial potential difference. Paediatr Respir Rev 2009; 10:220-6. [PMID: 19879513 DOI: 10.1016/j.prrv.2009.05.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Revised: 05/19/2009] [Accepted: 05/26/2009] [Indexed: 11/15/2022]
Abstract
Post-natal screening allied with genetic mutation testing has altered our perception of cystic fibrosis (CF) as a clinical entity. Increasingly, infants identified through screening programmes have few or no symptoms or present with atypical forms of the disease. We review how the sweat test has evolved to be the gold standard for confirming the diagnosis of CF and examine its limitations. Other physiological measurements, including nasal potential difference and intestinal current measurement, which might aid in establishing the diagnosis, particularly in patients exhibiting a mild phenotype, are also considered.
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Affiliation(s)
- C J Taylor
- Sheffield Paediatric Cystic Fibrosis Centre, Sheffield, Academic Unit of Child Health, University of Sheffield, UK.
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Abstract
The term "mucoactive agent" refers to any medication used to improve the clearance of airway secretions. It is not synonymous with the word "mucolytic" as this strictly means a drug that decreases the viscosity of secretions. In many cases, decreased viscosity will adversely affect cough transport. For this reason many of the older mucolytic agents such as acetylcysteine are not effective for the therapy of lung disease and their use is not recommended. I review here the many classes of mucoactive agents and identify a number of medications with great promise for the treatment of chronic airway disease.
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Affiliation(s)
- Bruce K Rubin
- Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157-1081, USA.
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14
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Abstract
Airway mucus hypersecretion is a clinical feature of a number of childhood diseases, including asthma and bronchitis-associated conditions. However, compared with adults, there is relatively scarce information concerning mucus pathophysiology in respiratory diseases in children. The available evidence indicates many similarities between adult and childhood respiratory hypersecretory conditions, including goblet-cell hyperplasia and submucosal gland hypertrophy, and airway mucus plugging in asthma. Consequently, it is likely that treatments that are effective in adults would be effective in children. Numerous therapeutic targets are linked to the pathophysiology of airway mucus hypersecretion in experimental models and adults with respiratory disease. Whether or not these same targets are relevant in children is for the most part unclear. These targets include the inflammatory cells mediating the inflammatory response that generates the hypersecretory phenotype, and highly specific cellular elements such as epidermal growth factor receptor tyrosine kinase and calcium-activated chloride (CACL) channels. Identification of these factors is linked with the development of different classes of pharmacotherapeutic molecules directed at these targets. Compounds with a broader spectrum of anti-inflammatory activity are likely to be more effective than compounds with restricted activity. However, certain highly specific targets, such as human CACL1 channels, appear to be strongly associated with the development of an airway hypersecretory phenotype. Data from current clinical trials in adults with blockers of these specific targets are awaited with great interest. The hope is that, if effective, pediatric trials with these compounds could be initiated with a view to alleviation of the clinical impact of airway mucus hypersecretion in children. A significant challenge to the therapeutic progression of these new compounds is effective delivery to the airways in children, with the research effort into development of new compounds matched by advances in inhaler design.
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Affiliation(s)
- Duncan F Rogers
- Thoracic Medicine, National Heart and Lung Institute, Imperial College London, London, UK.
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15
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King M, Rubin BK. Pharmacological approaches to discovery and development of new mucolytic agents. Adv Drug Deliv Rev 2002; 54:1475-90. [PMID: 12458156 DOI: 10.1016/s0169-409x(02)00156-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Airway mucus is the secretory product of the mucous cells; it is a variable mixture of water, mucous glycoproteins, low molecular weight ions, proteins, and lipids, whose physical properties are important for airway defense. The factors that contribute to the physical properties of mucus are complex, and there are a number of pharmacological strategies that can potentially serve to improve the clearability of airway mucus. Novel mucoactive approaches include strategies for mucoregulation--decreasing the abnormal volume of mucus secretion--and medications designed to improve the cough clearability of airway secretions. In vitro results suggest potential benefits from the additive effects of selected combinations of mucoactive medications. Further studies are required to confirm these findings, to perform direct assessments of mucus clearability, and to extend the observations to patients with various types of pulmonary diseases where mucoactive treatments are required.
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Affiliation(s)
- Malcolm King
- University of Alberta Pulmonary Research Group, 173 Heritage Medical Research Center, Edmonton, Alberta T6G 2S2, Canada.
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Rubin BK. An in vitro comparison of the mucoactive properties of guaifenesin, iodinated glycerol, surfactant, and albuterol. Chest 1999; 116:195-200. [PMID: 10424525 DOI: 10.1378/chest.116.1.195] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVE The mechanism of action of potential mucoactive agents could relate to effects on the mucociliary apparatus or to direct effects on the secretions. The purpose of this study was to determine the in vitro effects of several agents on the properties of mucus simulants and sputum collected from 30 adults with stable chronic bronchitis. DESIGN Sputum or simulants were analyzed untreated and after the addition of the test agent at 1:5 volume to volume ratio for a contact period of 60 s. The concentrations of the agents were as follows: guaifenesin, 20 mg/mL; iodinated glycerol, 3 mg/mL; surfactant (Exosurf; Glaxo Wellcome; Research Triangle Park, NC) containing 13.5 mg of phospholipid per milliliter; albuterol, 5 mg/mL; and amphibian Ringer's solution (ARS) as a control. Dynamic viscoelasticity and surface mechanical impedance were measured in a magnetic microrheometer. Cohesiveness was measured using a filancemeter. The wettability of a hydrophilic surface was measured using an image processing system. The mucociliary transportability of sputum was timed on the frog palate, and cough transportability (CTR) was measured in a cough machine. RESULTS When compared to sputum that had no test agent or ARS added, all agents reduced sputum elasticity G', with surfactant, albuterol, and guaifenesin significant at p < 0.001. As well, guaifenesin (p = 0.006), albuterol (p = 0.003), and surfactant (p = 0.02) decreased surface mechanical impedance (frictional adhesiveness) compared to untreated sputum. However, there were no significant changes in wettability, hydration, cohesiveness, or CTR with any agent, and there were no significant changes in the properties of sputum or simulants treated with test agents when compared to those treated with ARS. Guaifenesin irreversibly disrupted mucociliary transport when applied directly to the frog palate. CONCLUSIONS These agents appear to have a minimal direct action on sputum in vitro, suggesting that at the concentrations studied, these agents do not have a significant beneficial effect on either the mucociliary transportability or CTR of chronic bronchitis sputum. However, there could be an effect of some of these agents after oral administration, especially if there is a secondary effect of the agent on an effector cell.
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Affiliation(s)
- B K Rubin
- Department of Pediatrics, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1081, USA.
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Affiliation(s)
- M S Quraishi
- Department of Otorhinolaryngology, University Hospital, Nottingham, UK
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