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Tesfa D, Tiruneh SA, Azanaw MM, Gebremariam AD, Engidaw MT, Tiruneh M, Dessalegn T, Zemene MA, Sisay E. Prognostic risk score development to predict birth asphyxia using maternal and fetal characteristics in South Gondar zone hospitals, north West Ethiopia. BMC Pediatr 2022; 22:537. [PMID: 36088319 PMCID: PMC9463805 DOI: 10.1186/s12887-022-03582-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 08/25/2022] [Indexed: 12/03/2022] Open
Abstract
Background Birth asphyxia leads to profound systemic and neurological sequela to decrease blood flow or oxygen to the fetus followed by lethal progressive or irreversible life-long pathologies. In low resource setting countries, birth asphyxia remains a critical condition. This study aimed to develop and validate prognostic risk scores to forecast birth asphyxia using maternal and neonatal characteristics in south Gondar zone hospitals. Methods Prospective cohorts of 404 pregnant women were included in the model in south Gondar Zone Hospitals, Northwest Ethiopia. To recognize potential prognostic determinants for birth asphyxia, multivariable logistic regression was applied. The model discrimination probability was checked using the receiver operating characteristic curve (AUROC) and the model calibration plot was assessed using the ‘givitiR’ R-package. To check the clinical importance of the model, a cost-benefit analysis was done through a decision curve and the model was internally validated using bootstrapping. Lastly, a risk score prediction measurement was established for simple application. Results Of 404, 108 (26.73%) (95% CI: 22.6–31.3) newborns were exposed to birth asphyxia during the follow-up time. Premature rupture of membrane, meconium aspiration syndrome, malpresentation, prolonged labor, Preterm, and tight nuchal was the significant prognostic predictors of birth asphyxia. The AUROC curve for birth asphyxia was 88.6% (95% CI: 84.6-92.2%), which indicated that the tool identified the newborns at risk for birth asphyxia very well. The AUROC of the simplified risk score algorithm, was 87.9 (95% CI, 84.0– 91.7%) and the risk score value of 2 was selected as the optimal cut-off value, with a sensitivity of 78.87%, a specificity of 83.26%, a positive predictive value of 63.23%, and a negative predictive value of 91.52%. Conclusions We established birth asphyxia prediction tools by applying non-sophisticated maternal and neonatal characteristics for resource scares countries. The driven score has very good discriminative ability and prediction performance. This risk score tool would allow reducing neonatal morbidity and mortality related to birth asphyxia. Consequently, it will improve the overall neonatal health / under-five child health in low-income countries.
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Amsalu S, Dheresa M, Dessie Y, Eshetu B, Balis B. Birth asphyxia, determinants, and its management among neonates admitted to NICU in Harari and Dire Dawa Public Hospitals, eastern Ethiopia. Front Pediatr 2022; 10:966630. [PMID: 36727014 PMCID: PMC9885038 DOI: 10.3389/fped.2022.966630] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/30/2022] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Despite a declining neonatal mortality rate globally, Ethiopia has scored 29-30 deaths per 1,000 live births. Birth asphyxia is a major contributor to neonatal mortality, where 4-9 million newborns develop birth asphyxia each year. This study aimed to assess the prevalence of birth asphyxia, its determinants, and its management among neonates admitted to the NICU in Harari and Dire Dawa public hospitals. METHODS A facility-based cross-sectional study was conducted among 409 randomly selected neonates and their index mothers admitted to neonatal intensive care units of public hospitals in Harari and Dire Dawa from June 20 to August 20, 2021. Data were collected through card review and interviewer-administered questionnaires. The collected data were entered into Epi data version 3.1 and exported to SPSS version 20 for analysis. Logistic regression models were fitted to identify factors associated with birth asphyxia. Adjusted odds ratios along with 95% CIs were estimated to measure the strength of the association, and statistical significance was declared at p-value <0.05. RESULTS One-fifth of neonates [20.8% (95% CI: 16.4, 24.6%)] had birth asphyxia. Neonates born by instrumental delivery (AOR = 2.29, 95% CI: 1.10, 4.76) and neonates born to mother with PIH (AOR = 3.49, 95% CI: 1.47, 8.27), PROM (AOR = 2.23, 95% CI: 1.17, 4.26), and chorioamnionitis (AOR = 3.26, 95% CI: 1.10, 9.61) were more likely to have birth asphyxia compared to their counterpart. Ventilation with a bag and mask 50(58.8), putting on free oxygen 19(22.4), and endotracheal intubation 15(17.6) were taken as management methods. CONCLUSION One out of five neonates had birth asphyxia. This urges care providers to adhere to national guidelines of obstetrics and neonatal continuum care. They also need to decrease instrumental delivery and treat PIH, PROM, and chorioamnionitis.
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Affiliation(s)
- Sewmehon Amsalu
- Department Midwifery, College of Health and Medical Sciences, Dire Dawa University, Dire Dawa, Ethiopia
| | - Merga Dheresa
- School of Public Health, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | - Yadeta Dessie
- School of Public Health, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | - Bajrond Eshetu
- School of Nursing and Midwifery, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | - Bikila Balis
- School of Nursing and Midwifery, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
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Müller H, Schmiedl A, Weiss C, Ai M, Jung S, Renner M. DMBT1 is upregulated in lung epithelial cells after hypoxia and changes surfactant ultrastructure. Pediatr Pulmonol 2020; 55:2964-2969. [PMID: 32770804 DOI: 10.1002/ppul.25018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/05/2020] [Indexed: 11/11/2022]
Abstract
BACKGROUND Hypoxia and asphyxia are known to induce surfactant inactivation in newborns. Deleted in Malignant Brain Tumors 1 (DMBT1) is an innate immunity protein with functions in epithelial differentiation and angiogenesis. It was detected in hyaline membranes of infants with respiratory distress syndrome. Human recombinant DMBT1 is able to increase the surface tension of exogenous surfactant preparations in a dose-dependent manner. METHODS Immunohistochemistry was performed on lung sections of infants who died due to pre-, peri- or postnatal hypoxia. The lung epithelial cell line A549 was stably transfected with a DMBT1 (DMBT1+ cells) expression plasmid or with an empty plasmid (DMBT1- cells). The cells were cultured in normoxic or hypoxic conditions, and then DMBT1 as well as HIF-1α RNA expression were analyzed by using real-time-polymerase chain reaction. Human recombinant DMBT1 was added to the modified porcine natural surfactant Curosurf to examine the effect of DMBT1 on surfactant ultrastructure with electron microscopy. RESULTS DMBT1 expression was upregulated in human lung tissue after fetal/peri-/postnatal hypoxia. In addition, in vitro experiments showed increased DMBT1 RNA expression in A549 cells after hypoxia. HIF-1α was upregulated in both DMBT1+ and DMBT1- cells in response to hypoxia. The addition of human recombinant DMBT1 to Curosurf caused an impaired surfactant ultrastructure. CONCLUSIONS DMBT1 is upregulated in response to hypoxia and there seems to be a link between hypoxia and surfactant inactivation.
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Affiliation(s)
- Hanna Müller
- Division of Neonatology and Pediatric Intensive Care, Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Andreas Schmiedl
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Christel Weiss
- Department for Medical Statistics and Biomathematics, University Hospital Mannheim, Mannheim, Germany
| | - Maria Ai
- Division of Neonatology and Pediatric Intensive Care, Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Susan Jung
- Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Marcus Renner
- Institute of Pathology, University of Heidelberg, Heidelberg, Germany
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Autilio C, Echaide M, Shankar-Aguilera S, Bragado R, Amidani D, Salomone F, Pérez-Gil J, De Luca D. Surfactant Injury in the Early Phase of Severe Meconium Aspiration Syndrome. Am J Respir Cell Mol Biol 2020; 63:327-337. [PMID: 32348683 DOI: 10.1165/rcmb.2019-0413oc] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
No in vivo data are available regarding the effect of meconium on human surfactant in the early stages of severe meconium aspiration syndrome (MAS). In the present study, we sought to characterize the changes in surfactant composition, function, and structure during the early phase of meconium injury. We designed a translational prospective cohort study of nonbronchoscopic BAL of neonates with severe MAS (n = 14) or no lung disease (n = 18). Surfactant lipids were analyzed by liquid chromatography-high-resolution mass spectrometry. Secretory phospholipase A2 subtypes IB, V, and X and SP-A (surfactant protein A) were assayed by ELISA. SP-B and SP-C were analyzed by Western blotting under both nonreducing and reducing conditions. Surfactant function was assessed by adsorption test and captive bubble surfactometry, and lung aeration was evaluated by semiquantitative lung ultrasound. Surfactant nanostructure was studied using cryo-EM and atomic force microscopy. Several changes in phospholipid subclasses were detected during MAS. Lysophosphatidylcholine species released by phospholipase A2 hydrolysis were increased. SP-B and SP-C were significantly increased together with some shorter immature forms of SP-B. Surfactant function was impaired and correlated with poor lung aeration. Surfactant nanostructure was significantly damaged in terms of vesicle size, tridimensional complexity, and compactness. Various alterations of surfactant phospholipids and proteins were detected in the early phase of severe meconium aspiration and were due to hydrolysis and inflammation and a defensive response. This impairs both surfactant structure and function, finally resulting in reduced lung aeration. These findings support the development of new surfactant protection and antiinflammatory strategies for severe MAS.
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Affiliation(s)
- Chiara Autilio
- Department of Biochemistry and Molecular Biology and Research Institute "Hospital 12 de Octubre (imas12)", Complutense University, Madrid, Spain
| | - Mercedes Echaide
- Department of Biochemistry and Molecular Biology and Research Institute "Hospital 12 de Octubre (imas12)", Complutense University, Madrid, Spain
| | - Shivani Shankar-Aguilera
- Division of Pediatrics and Neonatal Critical Care, A. Béclère Medical Center, Paris Saclay University Hospitals, APHP, Paris, France
| | - Rafael Bragado
- Research Institute "Instituto de Investigación Sanitaria-Fundación Jiménez Díaz (IIS FJD)", Madrid, Spain
| | - Davide Amidani
- Pharmacology and Toxicology Department Preclinical R&D, Chiesi Farmaceutici, Parma, Italy; and
| | - Fabrizio Salomone
- Pharmacology and Toxicology Department Preclinical R&D, Chiesi Farmaceutici, Parma, Italy; and
| | - Jesús Pérez-Gil
- Department of Biochemistry and Molecular Biology and Research Institute "Hospital 12 de Octubre (imas12)", Complutense University, Madrid, Spain
| | - Daniele De Luca
- Division of Pediatrics and Neonatal Critical Care, A. Béclère Medical Center, Paris Saclay University Hospitals, APHP, Paris, France.,Physiopathology and Therapeutic Innovation Unit, INSERM U999, Paris-Saclay University, Paris, France
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Abdo RA, Halil HM, Kebede BA, Anshebo AA, Gejo NG. Prevalence and contributing factors of birth asphyxia among the neonates delivered at Nigist Eleni Mohammed memorial teaching hospital, Southern Ethiopia: a cross-sectional study. BMC Pregnancy Childbirth 2019; 19:536. [PMID: 31888542 PMCID: PMC6937931 DOI: 10.1186/s12884-019-2696-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 12/23/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Birth asphyxia is a major contributor to neonatal mortality worldwide. In Ethiopia, birth asphyxia remains a severe condition that leads to significant mortality and morbidity. This study aims to assess the prevalence and contributing factors of birth asphyxia among the neonates delivered at the Nigist Eleni Mohammed Memorial Teaching Hospital, Southern Ethiopia. METHODS This hospital-based cross-sectional study was carried out on 279 participants using the systematic sampling method during June 1-30, 2019. Data were collected using a pretested structured interviewer administered questionnaire, check list and chart review, which was used to retrieve medical information and mother's test results that could not be captured by the interview. Data were entered into EpiData (version 3.1) and analyzed using SPSS software (version 24). Multivariable regression analysis was used to identify the association between the independent variables and outcome variable with a 95% confidence interval (CI). RESULT The overall prevalence of birth asphyxia among newborns was found to be 15.1%. Factors that were significantly associated with birth asphyxia included mothers aged ≥35 (AOR = 6.4; 95% CI = 2.0-20.5), primigravida (AOR = 5.1; 95% CI =2.0-13.3), prolonged second stage of labor (AOR = 4.6; 95%CI =1.6-13.3), preterm birth (AOR = 4.7; 95% CI =1.5-14.1), meconium stained amniotic fluid (AOR = 7.5; 95% CI =2.5-21.4) and tight nuchal (AOR = 3.1; 95% CI =1.2-9.3). CONCLUSION Birth asphyxia is still prevalent in the study setting. The obtained findings indicated that the mothers aged ≥35, being primigravida, preterm birth, meconium stained amniotic fluid and tight nuchal were the factors associated with birth asphyxia. The results of this study show the need for better maternal care, creating awareness about contributing factors of birth asphyxia to the maternity health professionals, careful monitoring of labor, and identifying and taking proper measures that could help in reducing the occurrence of birth asphyxia.
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Affiliation(s)
- Ritbano Ahmed Abdo
- Department of Midwifery, College of Medicine and Health Sciences, Wachemo University, Hossana, Ethiopia.
| | - Hassen Mosa Halil
- Department of Midwifery, College of Medicine and Health Sciences, Wachemo University, Hossana, Ethiopia
| | - Biruk Assefa Kebede
- Department of Midwifery, College of Medicine and Health Sciences, Wachemo University, Hossana, Ethiopia
| | - Abebe Alemu Anshebo
- Department of Midwifery, College of Medicine and Health Sciences, Wachemo University, Hossana, Ethiopia
| | - Negeso Gebeyehu Gejo
- Department of Midwifery, College of Medicine and Health Sciences, Wachemo University, Hossana, Ethiopia
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6
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Fröhlich E. Biological Obstacles for Identifying In Vitro- In Vivo Correlations of Orally Inhaled Formulations. Pharmaceutics 2019; 11:E316. [PMID: 31284402 PMCID: PMC6680885 DOI: 10.3390/pharmaceutics11070316] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 06/15/2019] [Accepted: 07/02/2019] [Indexed: 12/26/2022] Open
Abstract
Oral inhalation of drugs is the classic therapy of obstructive lung diseases. In contrast to the oral route, the link between in vitro and in vivo findings is less well defined and predictive models and parameters for in vitro-in vivo correlations are missing. Frequently used in vitro models and problems in obtaining in vivo values to establish such models and to identify the action of formulations in vivo are discussed. It may be concluded that major obstacles to link in vitro parameters on in vivo action include lack of treatment adherence and incorrect use of inhalers by patients, variation in inhaler performance, changes by humidity, uncertainties about lung deposition, and difficulties to measure drug levels in epithelial lining fluid and tissue. Physiologically more relevant in vitro models, improvement in inhaler performance, and better techniques for in vivo measurements may help to better understand importance and interactions between individual in vitro parameters in pulmonary delivery.
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Affiliation(s)
- Eleonore Fröhlich
- Center for Medical Research, Medical University of Graz, 8010 Graz, Austria.
- Research Center Pharmaceutical Engineering GmbH, 8010 Graz, Austria.
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7
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Jörger A, Acevedo C, Busley D, Ganter M, Schmiedl A, Humann-Ziehank E. Stereological and biophysical characteristics of the ovine surfactant system and its changes caused by ovine pulmonary adenocarcinoma. Res Vet Sci 2017. [DOI: 10.1016/j.rvsc.2017.06.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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8
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Steffen L, Ruppert C, Hoymann HG, Funke M, Ebener S, Kloth C, Mühlfeld C, Ochs M, Knudsen L, Lopez-Rodriguez E. Surfactant replacement therapy reduces acute lung injury and collapse induration-related lung remodeling in the bleomycin model. Am J Physiol Lung Cell Mol Physiol 2017; 313:L313-L327. [PMID: 28450283 DOI: 10.1152/ajplung.00033.2017] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 04/11/2017] [Accepted: 04/22/2017] [Indexed: 12/13/2022] Open
Abstract
Bleomycin-induced lung injury leads to surfactant dysfunction and permanent loss of alveoli due to a remodeling process called collapse induration. Collapse induration also occurs in acute interstitial lung disease and idiopathic pulmonary fibrosis in humans. We hypothesized that surfactant dysfunction aggravates lung injury and early remodeling resulting in collapse induration within 7 days after lung injury. Rats received bleomycin to induce lung injury and either repetitive surfactant replacement therapy (SRT: 100 mg Curosurf/kg BW = surf group) or saline (0.9% NaCl = saline group). After 3 (D3) or 7 (D7) days, invasive pulmonary function tests were performed to determine tissue elastance (H) and static compliance (Cst). Bronchoalveolar lavage (BAL) was taken for surfactant function, inflammatory markers, and protein measurements. Lungs were fixed by vascular perfusion for design-based stereology and electron microscopic analyses. SRT significantly improved minimum surface tension of alveolar surfactant as well as H and Cst at D3 and D7. At D3 decreased inflammatory markers including neutrophilic granulocytes, IL-1β, and IL-6 correlated with reduced BAL-protein levels after SRT. Numbers of open alveoli were significantly increased at D3 and D7 in SRT groups whereas at D7 there was also a significant reduction in septal wall thickness and parenchymal tissue volume. Septal wall thickness and numbers of open alveoli highly correlated with improved lung mechanics after SRT. In conclusion, reduction in surface tension was effective to stabilize alveoli linked with an attenuation of parameters of acute lung injury at D3 and collapse induration at D7. Hence, SRT modifies disease progression to collapse induration.
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Affiliation(s)
- Lilian Steffen
- Institute of Functional and Applied Anatomy, Hannover Medical School, Germany and Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research, Hannover, Germany
| | - Clemens Ruppert
- Department of Internal Medicine, Justus-Liebig-University Giessen, Germany, and Universities of Giessen and Marburg Lung Center, Member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Heinz-Gerd Hoymann
- Fraunhofer Institute of Toxicology and Experimental Medicine, Hannover, Germany
| | - Manuela Funke
- Department of Pulmonary Medicine, Bern University Hospital, University of Bern, Bern, Switzerland.,Department of Clinical Research, University of Bern, Bern, Switzerland; and
| | - Simone Ebener
- Department of Pulmonary Medicine, Bern University Hospital, University of Bern, Bern, Switzerland.,Department of Clinical Research, University of Bern, Bern, Switzerland; and
| | - Christina Kloth
- Institute of Functional and Applied Anatomy, Hannover Medical School, Germany and Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research, Hannover, Germany
| | - Christian Mühlfeld
- Institute of Functional and Applied Anatomy, Hannover Medical School, Germany and Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research, Hannover, Germany.,Cluster of Excellence Regenerative Biology to Reconstructive Therapy, Hannover, Germany
| | - Matthias Ochs
- Institute of Functional and Applied Anatomy, Hannover Medical School, Germany and Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research, Hannover, Germany.,Cluster of Excellence Regenerative Biology to Reconstructive Therapy, Hannover, Germany
| | - Lars Knudsen
- Institute of Functional and Applied Anatomy, Hannover Medical School, Germany and Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research, Hannover, Germany; .,Cluster of Excellence Regenerative Biology to Reconstructive Therapy, Hannover, Germany
| | - Elena Lopez-Rodriguez
- Institute of Functional and Applied Anatomy, Hannover Medical School, Germany and Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research, Hannover, Germany.,Cluster of Excellence Regenerative Biology to Reconstructive Therapy, Hannover, Germany
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Echaide M, Autilio C, Arroyo R, Perez-Gil J. Restoring pulmonary surfactant membranes and films at the respiratory surface. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:1725-1739. [PMID: 28341439 DOI: 10.1016/j.bbamem.2017.03.015] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/14/2017] [Accepted: 03/19/2017] [Indexed: 02/08/2023]
Abstract
Pulmonary surfactant is a complex of lipids and proteins assembled and secreted by the alveolar epithelium into the thin layer of fluid coating the respiratory surface of lungs. There, surfactant forms interfacial films at the air-water interface, reducing dramatically surface tension and thus stabilizing the air-exposed interface to prevent alveolar collapse along respiratory mechanics. The absence or deficiency of surfactant produces severe lung pathologies. This review describes some of the most important surfactant-related pathologies, which are a cause of high morbidity and mortality in neonates and adults. The review also updates current therapeutic approaches pursuing restoration of surfactant operative films in diseased lungs, mainly through supplementation with exogenous clinical surfactant preparations. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá.
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Affiliation(s)
- Mercedes Echaide
- Dept. Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, Madrid, Spain
| | - Chiara Autilio
- Dept. Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, Madrid, Spain
| | - Raquel Arroyo
- Dept. Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, Madrid, Spain
| | - Jesus Perez-Gil
- Dept. Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, Madrid, Spain.
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Kopincova J, Calkovska A. Meconium-induced inflammation and surfactant inactivation: specifics of molecular mechanisms. Pediatr Res 2016; 79:514-21. [PMID: 26679157 DOI: 10.1038/pr.2015.265] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 10/03/2015] [Indexed: 12/21/2022]
Abstract
This review summarizes neonatal meconium aspiration syndrome in light of meconium-induced inflammation and inflammatory surfactant inactivation, related to both endogenous and therapeutic exogenous surfactant. The wide effect of meconium on surfactant properties is divided into three points. Direct effect of meconium on surfactant properties refers mainly to fragmentation of dipalmitoylphosphatidylcholine and other surfactant phospholipids together with cleavage of surfactant proteins. Initiation of inflammatory response due to activation of receptors by yet unspecified compounds involves complement and Toll-like receptor activation. A possible role of lung collectins, surfactant proteins A and D, which can exert both pro- and anti-inflammatory reactions, is discussed. Initiation of inflammatory response by specified compounds in meconium reflects inflammatory functioning of cytokines, bile acids, and phospholipases contained in meconium. Unifying sketch of many interconnections in all these actions aims at providing integrated picture of inflammatory surfactant inactivation.
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Affiliation(s)
- Jana Kopincova
- Department of Physiology and Martin Biomedical Centre, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Slovak Republic
| | - Andrea Calkovska
- Department of Physiology and Martin Biomedical Centre, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Slovak Republic
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Minocchieri S, Knoch S, Schoel WM, Ochs M, Nelle M. Nebulizing poractant alfa versus conventional instillation: Ultrastructural appearance and preservation of surface activity. Pediatr Pulmonol 2014; 49:348-56. [PMID: 24039226 DOI: 10.1002/ppul.22838] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 04/23/2013] [Accepted: 05/20/2013] [Indexed: 11/06/2022]
Abstract
BACKGROUND Nebulized surfactant therapy has been proposed as an alternative method of surfactant administration. The use of a perforated vibrating membrane nebulizer provides a variety of advantages over conventional nebulizers. We investigated the molecular structure and integrity of poractant alfa pre- and post-nebulization. METHOD Curosurf® was nebulized using an Investigational eFlow® Nebulizer System. Non-nebulized surfactant ("NN"), recollected surfactant droplets from nebulization through an endotracheal tube ("NT") and nebulization of surfactant directly onto a surface ("ND") were investigated by transmission electron microscopy. Biophysical characteristics were assessed by the Langmuir-Wilhelmy balance and the Captive Bubble Surfactometer. RESULTS Volume densities of lamellar body-like forms (LBL) and multi-lamellar forms (ML) were high for "NN" and "NT" samples (38.8% vs. 47.7% for LBL and 58.2% vs. 47.8% for ML). In the "ND" sample, we found virtually no LBL's, ML's (72.6%) as well as uni-lamellar forms (16.4%) and a new structure, the "garland-like" forms (9.4%). Surface tension for "NN" and "NT" was 23.33 ± 0.29 and 25.77 ± 1.12 mN/m, respectively. Dynamic compression-expansion cycling minimum surface tensions were between 0.91 and 1.77 mN/m. CONCLUSION The similarity of surfactant characteristics of nebulized surfactant via a tube and the non-nebulized surfactant suggests that vibrating membrane nebulizers are suitable for surfactant nebulization. Alterations in surfactant morphology and characteristics after nebulization were transient. A new structural subtype of surfactant was identified.
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Affiliation(s)
- Stefan Minocchieri
- The University of Western Australia, Centre for Neonatal Research and Education, Perth, Australia; Department of Neonatology and Intensive Care, University Children's Hospital, Zurich, Switzerland; Department of Pediatrics, University Hospital Bern, Bern, Switzerland
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12
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Martínez Sarrasague M, Cimato A, Piehl L, Brites F, Facorro G. Effect of serum lipoproteins and cholesterol on an exogenous pulmonary surfactant. ESR analysis of structural changes and their relation with surfactant activity. Respir Physiol Neurobiol 2013; 189:581-7. [PMID: 23994827 DOI: 10.1016/j.resp.2013.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Revised: 08/02/2013] [Accepted: 08/14/2013] [Indexed: 12/15/2022]
Abstract
The study of structural changes in the surfactant may help to understand the mechanisms by which the surfactant is inactivated by serum. Here, we compared the in vitro effects of serum, albumin, lipoproteins (VLDL, LDL, HDL) and cholesterol on the dynamic and structural properties of surfactant suspensions by electronic spin resonance and surface tension measurements. Our results showed that albumin seems to be responsible for macrostructure disaggregation and increased rigidity in the hydrophobic region, but it did not affect surfactant activity. Fluidity in the polar area seems to be critical for proper physiological activity, and the changes induced by serum observed in this area would be generated by HDL or cholesterol, but the amount of cholesterol transferred by serum is not significant. Statistical analysis showed that surfactant activity correlated with the fluidity in the polar area but not with that in the hydrophobic region. We obtained strong evidence that among all the serum components tested, HDL is the one that causes the structural changes that compromise surfactant performance.
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Affiliation(s)
- María Martínez Sarrasague
- Cátedra de Física, Departamento de Fisicomatemática, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
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How to overcome surfactant dysfunction in meconium aspiration syndrome? Respir Physiol Neurobiol 2013; 187:58-63. [DOI: 10.1016/j.resp.2013.02.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 02/26/2013] [Accepted: 02/28/2013] [Indexed: 01/06/2023]
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14
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Pallem V, Kaviratna A, Chimote G, Banerjee R. Effect of meconium on surface properties of surfactant monolayers and liposomes. Colloids Surf A Physicochem Eng Asp 2010. [DOI: 10.1016/j.colsurfa.2010.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Zasadzinski JA, Stenger PC, Shieh I, Dhar P. Overcoming rapid inactivation of lung surfactant: analogies between competitive adsorption and colloid stability. BIOCHIMICA ET BIOPHYSICA ACTA 2010; 1798:801-28. [PMID: 20026298 PMCID: PMC2834873 DOI: 10.1016/j.bbamem.2009.12.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 12/13/2009] [Accepted: 12/15/2009] [Indexed: 01/05/2023]
Abstract
Lung surfactant (LS) is a mixture of lipids and proteins that line the alveolar air-liquid interface, lowering the interfacial tension to levels that make breathing possible. In acute respiratory distress syndrome (ARDS), inactivation of LS is believed to play an important role in the development and severity of the disease. This review examines the competitive adsorption of LS and surface-active contaminants, such as serum proteins, present in the alveolar fluids of ARDS patients, and how this competitive adsorption can cause normal amounts of otherwise normal LS to be ineffective in lowering the interfacial tension. LS and serum proteins compete for the air-water interface when both are present in solution either in the alveolar fluids or in a Langmuir trough. Equilibrium favors LS as it has the lower equilibrium surface pressure, but the smaller proteins are kinetically favored over multi-micron LS bilayer aggregates by faster diffusion. If albumin reaches the interface, it creates an energy barrier to subsequent LS adsorption that slows or prevents the adsorption of the necessary amounts of LS required to lower surface tension. This process can be understood in terms of classic colloid stability theory in which an energy barrier to diffusion stabilizes colloidal suspensions against aggregation. This analogy provides qualitative and quantitative predictions regarding the origin of surfactant inactivation. An important corollary is that any additive that promotes colloid coagulation, such as increased electrolyte concentration, multivalent ions, hydrophilic non-adsorbing polymers such as PEG, dextran, etc. added to LS, or polyelectrolytes such as chitosan, also promotes LS adsorption in the presence of serum proteins and helps reverse surfactant inactivation. The theory provides quantitative tools to determine the optimal concentration of these additives and suggests that multiple additives may have a synergistic effect. A variety of physical and chemical techniques including isotherms, fluorescence microscopy, electron microscopy and X-ray diffraction show that LS adsorption is enhanced by this mechanism without substantially altering the structure or properties of the LS monolayer.
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Affiliation(s)
- Joseph A Zasadzinski
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA.
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16
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Mühlfeld C, Becker L, Bussinger C, Vollroth M, Nagib R, Schaefer IM, Knudsen L, Richter J, Madershahian N, Wahlers T, Wittwer T, Ochs M. Exogenous surfactant in ischemia/reperfusion: Effects on endogenous surfactant pools. J Heart Lung Transplant 2010; 29:327-34. [DOI: 10.1016/j.healun.2009.07.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 07/28/2009] [Accepted: 07/29/2009] [Indexed: 11/26/2022] Open
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17
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Georgiev GA, Kutsarova E, Jordanova A, Tsanova A, Vassilieff C, Lalchev Z. Tuning of Surface Properties of Thin Lipid-Protein Films by Hydrophilic Non-Surface Active Polymers. BIOTECHNOL BIOTEC EQ 2009. [DOI: 10.1080/13102818.2009.10818483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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18
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Bronchoalveolar lavage with pulmonary surfactant/dextran mixture improves meconium clearance and lung functions in experimental meconium aspiration syndrome. Eur J Pediatr 2008; 167:851-7. [PMID: 17952467 DOI: 10.1007/s00431-007-0596-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2007] [Accepted: 08/21/2007] [Indexed: 10/22/2022]
Abstract
Surfactant lung lavage is a promising approach in the treatment of meconium aspiration syndrome (MAS). We hypothesise that the enrichment of modified natural surfactant with dextran will enhance meconium clearance from the airspaces during lung lavage and improve lung function in experimental MAS. Human meconium (30 mg/ml; 4 ml/kg) was instilled into the tracheal cannula of anaesthetised and paralysed adult rabbits to induce respiratory failure. The animals were then lavaged with saline (Sal), surfactant without (Surf) and with dextran (Surf+dex). Lung lavage (10 ml/kg in three portions) was performed with diluted surfactant (Curosurf, 10 mg/ml, 100 mg/kg) without or with dextran (3 mg/mg of surfactant phospholipids) or saline and the animals were conventionally ventilated with 100% O(2) for an additional hour. Lung functions were measured prior to and after meconium instillation, and 10, 30 and 60 min after lavage. The recovery of meconium in bronchoalveolar lavage (BAL) fluid was quantified. More meconium solids was recovered in the surfactant-lavaged than in the saline-lavaged groups (Surf: 12.4 +/- 3.9% and Surf+dex: 17.5 +/- 3.5% vs. Sal: 4.8 +/- 1.0%; both P < 0.01). Moreover, more meconium solids was obtained by Curosurf/dextran than by Curosurf-only lavage (P < 0.05). In the Surf group, the values for PaO(2)/FiO(2) were significantly higher than in the controls (at 60 min: 24.5 +/- 4.2 kPa vs.9.1 +/- 2.2 kPa, P < 0.01). An additional increase in oxygenation was seen in the Surf+dex group (at 60 min: 34.2 +/- 8.1 kPa, P vs. Surf group <0.01). The lung-thorax compliance was higher in the Surf+dex group in comparison with the Sal and Surf groups (at 60 min: 9.6 +/- 0.9 vs.7.6 +/- 1.2, P < 0.01 and 8.0 +/- 0.7 ml/kPa/kg, P < 0.05). The enrichment of Curosurf with dextran improves meconium clearance and lung functions in surfactant-lavaged rabbits with meconium aspiration.
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Mühlfeld C, Liakopoulos OJ, Schaefer IM, Schöndube FA, Richter J, Dörge H. Methylprednisolone Fails to Preserve Pulmonary Surfactant and Blood–Air Barrier Integrity in a Porcine Cardiopulmonary Bypass Model. J Surg Res 2008; 146:57-65. [PMID: 17583746 DOI: 10.1016/j.jss.2007.03.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 03/01/2007] [Accepted: 03/13/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND Pulmonary inflammation after cardiac surgery with cardiopulmonary bypass (CPB) has been linked to respiratory dysfunction and ultrastructural injury. Whether pretreatment with methylprednisolone (MP) can preserve pulmonary surfactant and blood-air barrier, thereby improving pulmonary function, was tested in a porcine CPB-model. MATERIALS AND METHODS After randomizing pigs to placebo (PLA; n = 5) or MP (30 mg/kg, MP; n = 5), animals were subjected to 3 h of CPB with 1 h of cardioplegic cardiac arrest. Hemodynamic data, plasma tumor necrosis factor-alpha (TNF-alpha, ELISA), and pulmonary function parameters were assessed before, 15 min after CPB, and 8 h after CPB. Lung biopsies were analyzed for TNF-alpha (Western blot) or blood-air barrier and surfactant morphology (electron microscopy, stereology). RESULTS Systemic TNF-alpha increased and cardiac index decreased at 8 h after CPB in PLA (P < 0.05 versus pre-CPB), but not in MP (P < 0.05 versus PLA). In both groups, at 8 h after CPB, PaO2 and PaO2/FiO2 were decreased and arterio-alveolar oxygen difference and pulmonary vascular resistance were increased (P < 0.05 versus baseline). Postoperative pulmonary TNF-alpha remained unchanged in both groups, but tended to be higher in PLA (P = 0.06 versus MP). The volume fraction of inactivated intra-alveolar surfactant was increased in PLA (58 +/- 17% versus 83 +/- 6%) and MP (55 +/- 18% versus 80 +/- 17%) after CPB (P < 0.05 versus baseline for both groups). Profound blood-air barrier injury was present in both groups at 8 h as indicated by an increased blood-air barrier integrity score (PLA: 1.28 +/- 0.03 versus 1.70 +/- 0.1; MP: 1.27 +/- 0.08 versus 1.81 +/- 0.1; P < 0.05). CONCLUSION Despite reduction of the systemic inflammatory response and pulmonary TNF-alpha generation, methylprednisolone fails to decrease pulmonary TNF-alpha and to preserve pulmonary surfactant morphology, blood-air barrier integrity, and pulmonary function after CPB.
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Affiliation(s)
- Christian Mühlfeld
- Department of Anatomy, Division of Electron Microscopy, University of Göttingen, Göttingen, Germany.
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20
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Zuo YY, Veldhuizen RAW, Neumann AW, Petersen NO, Possmayer F. Current perspectives in pulmonary surfactant--inhibition, enhancement and evaluation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:1947-77. [PMID: 18433715 DOI: 10.1016/j.bbamem.2008.03.021] [Citation(s) in RCA: 361] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 03/26/2008] [Accepted: 03/26/2008] [Indexed: 02/06/2023]
Abstract
Pulmonary surfactant (PS) is a complicated mixture of approximately 90% lipids and 10% proteins. It plays an important role in maintaining normal respiratory mechanics by reducing alveolar surface tension to near-zero values. Supplementing exogenous surfactant to newborns suffering from respiratory distress syndrome (RDS), a leading cause of perinatal mortality, has completely altered neonatal care in industrialized countries. Surfactant therapy has also been applied to the acute respiratory distress syndrome (ARDS) but with only limited success. Biophysical studies suggest that surfactant inhibition is partially responsible for this unsatisfactory performance. This paper reviews the biophysical properties of functional and dysfunctional PS. The biophysical properties of PS are further limited to surface activity, i.e., properties related to highly dynamic and very low surface tensions. Three main perspectives are reviewed. (1) How does PS permit both rapid adsorption and the ability to reach very low surface tensions? (2) How is PS inactivated by different inhibitory substances and how can this inhibition be counteracted? A recent research focus of using water-soluble polymers as additives to enhance the surface activity of clinical PS and to overcome inhibition is extensively discussed. (3) Which in vivo, in situ, and in vitro methods are available for evaluating the surface activity of PS and what are their relative merits? A better understanding of the biophysical properties of functional and dysfunctional PS is important for the further development of surfactant therapy, especially for its potential application in ARDS.
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Affiliation(s)
- Yi Y Zuo
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada
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21
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Müller H, End C, Renner M, Helmke BM, Gassler N, Weiss C, Hartl D, Griese M, Hafner M, Poustka A, Mollenhauer J, Poeschl J. Deleted in Malignant Brain Tumors 1 (DMBT1) is present in hyaline membranes and modulates surface tension of surfactant. Respir Res 2007; 8:69. [PMID: 17908325 PMCID: PMC2164949 DOI: 10.1186/1465-9921-8-69] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 10/01/2007] [Indexed: 11/24/2022] Open
Abstract
Background Deleted in Malignant Brain Tumors 1 (DMBT1) is a secreted scavenger receptor cysteine-rich protein that binds various bacteria and is thought to participate in innate pulmonary host defense. We hypothesized that pulmonary DMBT1 could contribute to respiratory distress syndrome in neonates by modulating surfactant function. Methods DMBT1 expression was studied by immunohistochemistry and mRNA in situ hybridization in post-mortem lungs of preterm and full-term neonates with pulmonary hyaline membranes. The effect of human recombinant DMBT1 on the function of bovine and porcine surfactant was measured by a capillary surfactometer. DMBT1-levels in tracheal aspirates of ventilated preterm and term infants were determined by ELISA. Results Pulmonary DMBT1 was localized in hyaline membranes during respiratory distress syndrome. In vitro addition of human recombinant DMBT1 to the surfactants increased surface tension in a dose-dependent manner. The DMBT1-mediated effect was reverted by the addition of calcium depending on the surfactant preparation. Conclusion Our data showed pulmonary DMBT1 expression in hyaline membranes during respiratory distress syndrome and demonstrated that DMBT1 increases lung surface tension in vitro. This raises the possibility that DMBT1 could antagonize surfactant supplementation in respiratory distress syndrome and could represent a candidate target molecule for therapeutic intervention in neonatal lung disease.
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Affiliation(s)
- Hanna Müller
- Division of Neonatology, Department of Pediatrics, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg, Germany
| | - Caroline End
- Division of Molecular Genome Analysis, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
- Institute of Molecular Biology and Cell Culture Technology, University of Applied Sciences Mannheim, 68163 Mannheim, Germany
| | - Marcus Renner
- Division of Molecular Genome Analysis, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Burkhard M Helmke
- Institute of Pathology, University of Heidelberg, Im Neuenheimer Feld 220/221, 69120 Heidelberg, Germany
| | - Nikolaus Gassler
- Institute of Pathology, University of Heidelberg, Im Neuenheimer Feld 220/221, 69120 Heidelberg, Germany
- Institute of Pathology, University Hospital, RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany
| | - Christel Weiss
- Institute of Medical Statistics and Biomathematics, University Hospital Mannheim, Theodor-Kutzer-Ufer 1, 68135 Mannheim, Germany
| | - Dominik Hartl
- Children's Hospital, University of Munich, Lindwurmstrasse 2a, 80337 Munich, Germany
| | - Matthias Griese
- Children's Hospital, University of Munich, Lindwurmstrasse 2a, 80337 Munich, Germany
| | - Mathias Hafner
- Institute of Molecular Biology and Cell Culture Technology, University of Applied Sciences Mannheim, 68163 Mannheim, Germany
| | - Annemarie Poustka
- Division of Molecular Genome Analysis, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Jan Mollenhauer
- Division of Molecular Genome Analysis, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Johannes Poeschl
- Division of Neonatology, Department of Pediatrics, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg, Germany
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Braun A, Stenger PC, Warriner HE, Zasadzinski JA, Lu KW, Taeusch HW. A freeze-fracture transmission electron microscopy and small angle x-ray diffraction study of the effects of albumin, serum, and polymers on clinical lung surfactant microstructure. Biophys J 2007; 93:123-39. [PMID: 17416614 PMCID: PMC1914435 DOI: 10.1529/biophysj.106.095513] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Freeze-fracture transmission electron microscopy shows significant differences in the bilayer organization and fraction of water within the bilayer aggregates of clinical lung surfactants, which increases from Survanta to Curosurf to Infasurf. Albumin and serum inactivate all three clinical surfactants in vitro; addition of the nonionic polymers polyethylene glycol, dextran, or hyaluronic acid also reduces inactivation in all three. Freeze-fracture transmission electron microscopy shows that polyethylene glycol, hyaluronic acid, and albumin do not adsorb to the surfactant aggregates, nor do these macromolecules penetrate the interior water compartments of the surfactant aggregates. This results in an osmotic pressure difference that dehydrates the bilayer aggregates, causing a decrease in the bilayer spacing as shown by small angle x-ray scattering and an increase in the ordering of the bilayers as shown by freeze-fracture electron microscopy. Small angle x-ray diffraction shows that the relationship between the bilayer spacing and the imposed osmotic pressure for Curosurf is a screened electrostatic interaction with a Debye length consistent with the ionic strength of the solution. The variation in surface tension due to surfactant adsorption measured by the pulsating bubble method shows that the extent of surfactant aggregate reorganization does not correlate with the maximum or minimum surface tension achieved with or without serum in the subphase. Albumin, polymers, and their mixtures alter the surfactant aggregate microstructure in the same manner; hence, neither inhibition reversal due to added polymer nor inactivation due to albumin is caused by alterations in surfactant microstructure.
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Affiliation(s)
- Andreas Braun
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA
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Abstract
Although there is no doubt that administration of exogenous surfactant to very preterm babies who have respiratory distress syndrome is safe and efficacious, surfactant inactivation or deficiency plays a role in the pathophysiology of other pulmonary disorders affecting newborn infants. Preliminary data suggest that there may be a role for surfactant administration to babies who have meconium aspiration syndrome, pneumonia, and possibly bronchopulmonary dysplasia. Further investigation is necessary but seems warranted.
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Affiliation(s)
- Thierry Lacaze-Masmonteil
- Department of Pediatrics, Stollery Children's Hospital, University of Alberta, Edmonton, Alberta, Canada.
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25
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Been JV, Zimmermann LJI. What's new in surfactant? A clinical view on recent developments in neonatology and paediatrics. Eur J Pediatr 2007; 166:889-99. [PMID: 17516084 PMCID: PMC7102086 DOI: 10.1007/s00431-007-0501-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Accepted: 04/18/2007] [Indexed: 11/29/2022]
Abstract
UNLABELLED Surfactant therapy has significantly changed clinical practice in neonatology over the last 25 years. Recent trials in infants with respiratory distress syndrome (RDS) have not shown superiority of any natural surfactant over another. Advancements in the development of synthetic surfactants are promising, yet to date none has been shown to be superior to natural preparations. Ideally, surfactant would be administered without requiring mechanical ventilation. An increasing number of studies investigate the roles of alternative modes of administration and the use of nasal continuous positive airway pressure to minimise the need for mechanical ventilation. Whether children with other lung diseases benefit from surfactant therapy is less clear. Evidence suggests that infants with meconium aspiration syndrome and children with acute lung injury/acute respiratory distress syndrome may benefit, while no positive effect of surfactant is seen in infants with congenital diaphragmatic hernia. However, more research is needed to establish potential beneficial effects of surfactant administration in children with lung diseases other than RDS. Furthermore, genetic disorders of surfactant metabolism have recently been linked to respiratory diseases of formerly unknown origin. It is important to consider these disorders in the differential diagnosis of unexplained respiratory distress although no established treatment is yet available besides lung transplantation for the most severe cases. CONCLUSION Research around surfactant is evolving and recent developments include further evolution of synthetic surfactants, evaluation of surfactant as a therapeutic option in lung diseases other than RDS and the discovery of genetic disorders of surfactant metabolism. Ongoing research is essential to continue to improve therapeutic prospects for children with serious respiratory disease involving disturbances in surfactant.
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Affiliation(s)
- Jasper V Been
- Department of Paediatrics, Research Institute Growth and Development, Maastricht University Hospital, Maastricht, The Netherlands.
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