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Fee EL, Takahashi T, Takahashi Y, Carter SWD, Clarke MW, Milad MA, Usuda H, Ikeda H, Kumagai Y, Saito Y, Ireland DJ, Newnham JP, Saito M, Jobe AH, Kemp MW. Respiratory benefit in preterm lambs is progressively lost when the concentration of fetal plasma betamethasone is titrated below two nanograms per milliliter. Am J Physiol Lung Cell Mol Physiol 2023; 325:L628-L637. [PMID: 37697929 DOI: 10.1152/ajplung.00139.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/09/2023] [Accepted: 08/30/2023] [Indexed: 09/13/2023] Open
Abstract
Antenatal steroid therapy is the standard of care for women at imminent risk of preterm delivery. Current dosing regimens use suprapharmacological doses to achieve extended fetal steroid exposures. We aimed to determine the lowest fetal plasma betamethasone concentration sufficient to achieve functional preterm lung maturation. Ewes with single fetuses underwent surgery to install a fetal jugular catheter. Adopting a stepwise design, ewes were randomized to either a saline-only group (negative control group; n = 9) or one of four betamethasone treatment groups. Each betamethasone group fetus received a fetal intravenous infusion to target a constant plasma betamethasone level of either 1) 2 ng/mL (2 ng/mL positive control group, n = 9); 2) 1 ng/mL, (1 ng/mL group, n = 10); 3) 0.5 ng/mL (0.5 ng/mL group, n = 10); or 4) 0.25 ng/mL (0.25 ng/mL group, n = 10). Fetuses were infused for 48 h, delivered, and ventilated. The positive control group, negative control group, and mid-point 0.5 ng/mL group animals were tested first. An interim analysis informed the final betamethasone group tested. Positive control group animals had large, statistically significant improvements in respiratory function. Based on an interim analysis, the 1.0 ng/mL group was studied in favor of the 0.25 ng/mL group. Treatment efficacy was progressively lost at plasma betamethasone concentrations lower than 2 ng/mL. We demonstrated that the acute respiratory benefit conveyed by antenatal steroid exposure in the fetal sheep is progressively lost when constant fetal plasma betamethasone concentrations are reduced below a targeted value of 2 ng/mL.NEW & NOTEWORTHY Lung maturation benefits in preterm lambs were progressively lost when fetal plasma betamethasone concentrations fell below 2 ng/mL. The effective floor threshold for a robust, lung-maturing exposure likely lies between 1 and 2 ng betamethasone per milliliter of plasma. Hypothalamic pituitary adrenal axis signaling and immunocyte populations remained materially disrupted at subtherapeutic steroid concentrations. These data demonstrate the potential to improve antenatal steroid therapy using reduced dose regimens informed by glucocorticoid pharmacokinetics and pharmacodynamics.
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Affiliation(s)
- Erin L Fee
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- School of Biomedical Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Tsukasa Takahashi
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Yuki Takahashi
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Sean W D Carter
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
| | - Michael W Clarke
- Metabolomics Australia, Centre for Microscopy, Characterization and Analysis, The University of Western Australia, Perth, Western Australia, Australia
- School of Biomedical Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Mark A Milad
- Milad Pharmaceutical Consulting LLC, Plymouth, Michigan, United States
| | - Haruo Usuda
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Hideyuki Ikeda
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Yusaku Kumagai
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Yuya Saito
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Demelza J Ireland
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- School of Biomedical Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - John P Newnham
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
| | - Masatoshi Saito
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Alan H Jobe
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati School of Medicine, Cincinnati, Ohio, United States
| | - Matthew W Kemp
- Division of Obstetrics and Gynaecology, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
- School of Veterinary Medicine, Murdoch University, Perth, Western Australia, Australia
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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Schmid L, Hyde DM, Schittny JC. Microvascular maturation of the septal capillary layers takes place in parallel to alveolarization in human lungs. Am J Physiol Lung Cell Mol Physiol 2023; 325:L537-L541. [PMID: 37605833 PMCID: PMC11068427 DOI: 10.1152/ajplung.00425.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 08/02/2023] [Accepted: 08/16/2023] [Indexed: 08/23/2023] Open
Abstract
Primary and secondary septa formed during lung development contain a double-layered capillary network. To improve gas exchange, the capillary network is remodeled into a single-layered one, a process that is called microvascular maturation (MVM). It takes place during classical and continued alveolarization. Classical alveolarization is defined as a formation of new septa from immature septa and continued alveolarization as a formation from mature septa. Until now, MVM was never quantitatively evaluated in human lungs. To correlate alveolarization and MVM, and to determine the transition point from classical to continued alveolarization, the degree of MVM was stereologically estimated. In 12 human lungs (0.1-15 yr), the alveolar surface area of immature and mature septa was estimated stereologically by intersection counting. An MVM-quotient (RMVM) was defined as the mature alveolar surface area over total alveolar surface area. The MVM-quotient increased logarithmically over age and showed a biphasic increase similar to alveolarization. It did not reach 100% maturity in these samples. A linear correlation between the MVM-quotient and the logarithm of the number of alveoli was observed. We conclude that MVM increased logarithmically and biphasically in parallel to alveolarization until alveolarization ceased. However, at 2-3 yr of age three-quarters of the alveolar microvasculature are mature. This result may explain a previous postulate that MVM is finished at this age. We hypothesize that as long as alveolarization takes place, MVM will take place in parallel. We propose that the transition from classical to continued alveolarization takes place between the ages of 1-3 yr in humans.NEW & NOTEWORTHY Newly formed alveolar septa contain a double-layered capillary network. To optimize gas exchange, the two layers fuse to a single-layered capillary network during microvascular maturation. Because its timing is unknow in humans, microvascular maturation was stereologically estimated throughout postnatal human lung development. It is shown that maturation of the microvascular and alveolar septa takes place in parallel to alveolarization. At an age of 2-3 yr three-quarters of the septa are mature.
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Affiliation(s)
- Lukas Schmid
- Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Dallas M Hyde
- California National Primate Research Center, University of California, Davis, California, United States
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis, California, United States
| | - Johannes C Schittny
- Institute of Anatomy, University of Bern, Bern, Switzerland
- California National Primate Research Center, University of California, Davis, California, United States
- Center for Health and the Environment, University of California, Davis, California, United States
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Fee EL, Stock SJ, Kemp MW. Antenatal steroids: benefits, risks, and new insights. J Endocrinol 2023; 258:e220306. [PMID: 37130353 DOI: 10.1530/joe-22-0306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/02/2023] [Indexed: 05/04/2023]
Abstract
Being born before 37 weeks' gestation, or preterm birth, is a leading cause of early childhood death and life-long disability. Antenatal steroids (ANS) are recommended for women judged at risk of imminent preterm delivery. The primary intent of ANS treatment is to rapidly mature the fetal lungs to reduce the risk of mortality and lasting morbidity. Despite being used clinically for some 50 years, a large number of uncertainties remain surrounding the use of ANS. In particular, the choice of agent, dose/regimen, and appropriate gestational age range for ANS therapy all remain unclear. Unresolved concerns regarding the potential risk of harms from ANS treatment, especially in light of the modest benefits seen with expanding latepreterm administration, make it increasingly important to optimize the dosing and application of this important and widely used treatment. This review will serve to summarize past data, provide an update on recent developments, and chart a way forward to maximize the overall benefit of this important therapy.
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Affiliation(s)
- Erin L Fee
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Sarah J Stock
- University of Edinburgh Usher Institute, Edinburgh, Scotland, UK
| | - Matthew W Kemp
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
- School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
- Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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Jo HS, Lim MN, Cho SI. Required biological time for lung maturation and duration of invasive ventilation: a Korean cohort study of very low birth weight infants. Front Pediatr 2023; 11:1184832. [PMID: 37416815 PMCID: PMC10320392 DOI: 10.3389/fped.2023.1184832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 06/07/2023] [Indexed: 07/08/2023] Open
Abstract
Background We investigated the duration of invasive ventilation among very low birth weight (VLBW) infants to evaluate the current minimum time required for lung maturation to breathe without ventilator assistance after preterm birth. Methods A total of 14,658 VLBW infants born at ≤32+6 weeks between 2013 and 2020 were enrolled. Clinical data were collected from the Korean Neonatal Network, a national prospective cohort registry of VLBW infants from 70 neonatal intensive care units. Differences in the duration of invasive ventilation according to gestational age and birth weight were investigated. Recent trends and changes in assisted ventilation duration and associated perinatal factors between 2017-20 and 2013-16 were compared. Risk factors related to the duration of assisted ventilation were also identified. Results The overall duration of invasive ventilation was 16.3 days and the estimated minimum time required corresponded to 30+4 weeks of gestation. The median duration of invasive ventilation was 28.0, 13.0, 3.0, and 1.0 days at <26, 26-27, 28-29, and 30-32 weeks of gestation, respectively. In each gestational age group, the estimated minimum weaning points from the assisted ventilator were 29+5, 30+2, 30+2, and 31+5 weeks of gestation. The duration of non-invasive ventilation (17.9 vs. 22.5 days) and the incidence of bronchopulmonary dysplasia (28.1% vs. 31.9%) increased in 2017-20 (n = 7,221) than in 2013-16 (n = 7,437). In contrast, the duration of invasive ventilation and overall survival rate did not change during the periods 2017-20 and 2013-16. Surfactant treatment and air leaks were associated with increased duration of invasive ventilation (inverse hazard ratio 1.50, 95% CI, 1.04-2.15; inverse hazard ratio 1.62, 95% CI, 1.29-2.04). We expressed the incidence proportion of ventilator weaning according to the invasive ventilation duration using Kaplan-Meier survival curves. The slope of the curve slowly decreased as gestational age and birth weight were low and risk factors were present. Conclusions This population-based data on invasive ventilation duration among VLBW infants suggest the present limitation of postnatal lung maturation under specific perinatal conditions after preterm birth. Furthermore, this study provides detailed references for designing and/or assessing earlier ventilator weaning protocols and lung protection strategies by comparing populations or neonatal networks.
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Affiliation(s)
- Heui Seung Jo
- Department of Pediatrics, Kangwon National University Hospital, Chuncheon, Republic of Korea
| | - Myoung Nam Lim
- Biomedical Research Institute, Kangwon National University Hospital, Chuncheon, Republic of Korea
| | - Sung-Il Cho
- Graduate School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea
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Takahashi T, Jobe AH, Fee EL, Newnham JP, Schmidt AF, Usuda H, Kemp MW. The complex challenge of antenatal steroid therapy nonresponsiveness. Am J Obstet Gynecol 2022; 227:696-704. [PMID: 35932879 DOI: 10.1016/j.ajog.2022.07.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 07/11/2022] [Accepted: 07/18/2022] [Indexed: 11/01/2022]
Abstract
Antenatal steroid therapy is standard care for women at imminent risk of preterm delivery. When deliveries occur within 7 days of treatment, antenatal steroid therapy reduces the risk of neonatal death and improves preterm outcomes by exerting diverse developmental effects on the fetal organs, in particular the preterm lung and cardiovascular system. There is, however, sizable variability in antenatal steroid treatment efficacy, and an important percentage of fetuses exposed to antenatal steroid therapy do not respond sufficiently to derive benefit. Respiratory distress syndrome, for example, is a central metric of clinical trials to assess antenatal steroid outcomes. In the present analysis, we addressed the concept of antenatal steroid nonresponsiveness, and defined a failed or suboptimal response to antenatal steroids as death or a diagnosis of respiratory distress syndrome following treatment. For deliveries at 24 to 35 weeks' gestation, the number needed to treat to prevent 1 case of respiratory distress syndrome was 19 (95% confidence interval, 14-28). Reflecting gestation-dependent risk, for deliveries at >34 weeks' gestation the number needed to treat was 55 (95% confidence interval, 30-304), whereas for elective surgical deliveries at term this number was 106 (95% confidence interval, 61-421). We reviewed data from clinical and animal studies investigating antenatal steroid therapy to highlight the significant incidence of antenatal steroid therapy nonresponsiveness (ie, residual mortality or respiratory distress syndrome after treatment), and the potential mechanisms underpinning this outcome variability. The origins of this variability may be related to both the manner in which the therapy is applied (ie, the treatment regimen itself) and factors specific to the individual (ie, genetic variation, stress, infection). The primary aims of this review were: (1) to emphasize to the obstetrical and neonatal communities the extent of antenatal steroid response variability and its potential impact; (2) to propose approaches by which antenatal steroid therapy may be better applied to improve overall benefit; and (3) to stimulate further research toward the empirical optimization of this important antenatal therapy.
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Affiliation(s)
- Tsukasa Takahashi
- Division of Obstetrics and Gynaecology, University of Western Australia, Perth, Australia; Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Alan H Jobe
- Cincinnati Children's Hospital Medical Center, University of Cincinnati School of Medicine, Cincinnati, OH
| | - Erin L Fee
- Division of Obstetrics and Gynaecology, University of Western Australia, Perth, Australia
| | - John P Newnham
- Division of Obstetrics and Gynaecology, University of Western Australia, Perth, Australia
| | | | - Haruo Usuda
- Division of Obstetrics and Gynaecology, University of Western Australia, Perth, Australia; Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Matthew W Kemp
- Division of Obstetrics and Gynaecology, University of Western Australia, Perth, Australia; Center for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan; School of Veterinary and Life Sciences, Murdoch University, Perth, Australia; Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
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Takahashi T, Takahashi Y, Fee EL, Usuda H, Furfaro L, Newnham JP, Jobe AH, Kemp MW. Single nucleotide polymorphisms in surfactant protein A1 are not associated with a lack of responsiveness to antenatal steroid therapy in a pregnant sheep model. Physiol Rep 2022; 10:e15477. [PMID: 36200269 PMCID: PMC9535346 DOI: 10.14814/phy2.15477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/29/2022] [Accepted: 09/04/2022] [Indexed: 06/16/2023] Open
Abstract
Treatment with antenatal steroids (ANS) is standard practice for reducing the risk of respiratory distress in the preterm infant. Despite clear overall benefits when appropriately administered, many fetuses fail to derive benefit from ANS therapies. In standardized experiments using a pregnant sheep model, we have demonstrated that around 40% of ANS-exposed lambs did not have functional lung maturation significantly different from that of saline-treated controls. Surfactant protein A is known to play an important role in lung function. In this genotyping study, we investigated the potential correlation between polymorphisms in SFTPA1, messenger RNA and protein levels, and ventilation outcomes in animals treated with ANS. 45 preterm lambs were delivered 48 h after initial ANS therapy and 44 lambs were delivered 8 days after initial ANS therapy. The lambs were ventilated for 30 min after delivery. SFTPA1 mRNA expression in lung tissue was not correlated with arterial blood PaCO2 values at 30 min of ventilation in lambs delivered 48 h after treatment. SFTPA1 protein in lung tissue was significantly correlated with PaCO2 at 30 min of ventilation in lambs ventilated both 48 h and 8 days after ANS treatment. Six different single nucleotide polymorphisms (SNPs) in the Ovis aries SFTPA1 sequence were detected by Sanger Sequencing. No individual SNPs or SNP haplotypes correlated with alterations in PaCO2 at 30 min of ventilation or SFTPA1 protein levels in the lung. For the subset of animals analyzed in the present study, variable lung maturation responses to ANS therapy were not associated with mutations in SFTPA1.
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Affiliation(s)
- Tsukasa Takahashi
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
- Centre for Perinatal and Neonatal MedicineTohoku University HospitalSendaiJapan
| | - Yuki Takahashi
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
- Centre for Perinatal and Neonatal MedicineTohoku University HospitalSendaiJapan
| | - Erin L. Fee
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
| | - Haruo Usuda
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
- Centre for Perinatal and Neonatal MedicineTohoku University HospitalSendaiJapan
| | - Lucy Furfaro
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
| | - John P. Newnham
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
| | - Alan H. Jobe
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
- Perinatal Research, Department of PediatricsCincinnati Children's Hospital Medical Centre, University of CincinnatiCincinnatiOhioUSA
| | - Matthew W. Kemp
- Division of Obstetrics and GynaecologyThe University of Western AustraliaPerthWestern AustraliaAustralia
- Centre for Perinatal and Neonatal MedicineTohoku University HospitalSendaiJapan
- School of Veterinary and Life SciencesMurdoch UniversityPerthWestern AustraliaAustralia
- Department of Obstetrics and GynaecologyYong Loo Lin School of Medicine, National University of SingaporeSingapore
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Fee EL, Takahashi T, Takahashi Y, Carter S, Furfaro L, Clarke MW, Milad MA, Usuda H, Newnham JP, Saito M, Jobe AH, Kemp MW. 1% of the clinical dose used for antenatal steroid therapy is sufficient to induce lung maturation when administered directly to the preterm ovine fetus. Am J Physiol Lung Cell Mol Physiol 2022; 322:L853-L865. [PMID: 35438005 DOI: 10.1152/ajplung.00058.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION Antenatal steroids (ANS) are standard of care for women at imminent risk of preterm delivery. ANS accelerate functional maturation of the preterm fetal lung. Current dosing regimens expose the mother and fetus to high steroid levels with increased risk of adverse outcomes. Using a sheep model of pregnancy, we aimed to demonstrate that direct fetal administration would be sufficient to elicit functional maturation of the fetal lung. STUDY DESIGN Ewes and fetuses at 122d gestation underwent recovery surgery to install a fetal jugular catheter. Animals were then immediately randomised to either: i) fetal intravenous betamethasone phosphate infusion of 2ng/ml for 26 hours (fetal low-dose group; n=16); ii) fetal intravenous saline infusion for 26 hours and two maternal intramuscular injections of 0.25mg/kg betamethasone-phosphate + betamethasone-acetate (maternal clinical treatment group; n=12); or iii) fetal intravenous saline infusion for 26 hours (negative control group; n=10). Fetuses were delivered 48 hours after surgery, ventilated for 30 min to allow collection of physiological data, and euthanised. RESULTS The average betamethasone dose for the fetal low-dose group was 1% (0.3mg) of that used in the maternal clinical treatment group (30mg). At 30 minutes of ventilation, arterial paCO2, pH, heart rate and VEI were significantly (p<0.05) and equivalently improved in both the fetal low-dose and maternal clinical treatment group relative to negative control. CONCLUSION Maternal steroid administration was not required to elicit fetal lung maturation. Targeted fetal ANS treatments may allow the use of materially reduced antenatal steroid exposures, significantly reducing the risk of adverse outcomes.
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Affiliation(s)
- Erin L Fee
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia
| | - Tsukasa Takahashi
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Yuki Takahashi
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Sean Carter
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia
| | - Lucy Furfaro
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia
| | - Michael W Clarke
- Metabolomics Australia, Center for Microscopy, Characterization and Analysis, The University of Western Australia, Perth, Australia.,School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, Australia
| | - Mark A Milad
- Milad Pharmaceutical Consulting LLC, Plymouth, MI, United States
| | - Haruo Usuda
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - John P Newnham
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia
| | - Masatoshi Saito
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Alan Hall Jobe
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia.,Cincinnati Children's Hospital Medical Centre, University of Cincinnati School of Medicine, Cincinnati, OH, United States
| | - Matthew W Kemp
- Division of Obstetrics and Gynecology, Medical School, The University of Western Australia, Perth, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan.,School of Veterinary Medicine, Murdoch University, Perth, Australia.,Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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8
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Takahashi T, Takahashi Y, Fee EL, Saito M, Yaegashi N, Usuda H, Bridges JP, Milad MA, Furfaro L, Carter S, Schmidt AF, Newnham JP, Jobe AH, Kemp MW. Continuous but not pulsed low-dose fetal betamethasone exposures extend the durability of antenatal steroid therapy. Am J Physiol Lung Cell Mol Physiol 2022; 322:L784-L793. [PMID: 35380907 DOI: 10.1152/ajplung.00018.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Antenatal steroid (ANS) therapy is standard care for women at imminent risk of preterm labor. Despite extensive and long-standing use, 40-50% of babies exposed antenatally to steroids do not derive benefit; remaining undelivered 7d or more after ANS treatment is associated with a lack of treatment benefit, and increased risk of harms. We used a pregnant sheep model to evaluate the impact of continuous vs. pulsed ANS treatments on fetal lung maturation at an extended, eight-day treatment to delivery interval. Continuous low-dose ANS treatments for more than 72 hours in duration improved fetal lung maturation at eight days after treatment initiation. If fetal ANS exposure was interrupted, the beneficial ANS effect was lost. Truncated treatments, including that simulating the current clinical treatment regimen, did not improve lung function. Variable fetal lung maturation was correlated to the amount of saturated phosphatidylcholine present in the lung fluid. These data demonstrate that: i) the durability of ANS therapy may be enhanced by employing an extended, low-dose treatment regimen with reducing total dose; and ii) interrupting the continuity of fetal exposure by allowing it to fall below a minimal threshold was associated with comparably poor functional maturation of the preterm ovine lung.
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Affiliation(s)
- Tsukasa Takahashi
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Yuki Takahashi
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Erin L Fee
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Masatoshi Saito
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Nobuo Yaegashi
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Haruo Usuda
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - James P Bridges
- University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Mark A Milad
- Milad Pharmaceutical Consulting LLC, Plymouth, MI, United States
| | - Lucy Furfaro
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Sean Carter
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Augusto F Schmidt
- Department of Neonatology, Pulmonary Biology and Pediatrics, Cincinnati Children's Hospital Medical Centre, University of Cincinnati, Cincinnati, OH, United States.,Miller School of Medicine, University of Miami, Miami, FL, United States
| | - John P Newnham
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Alan Hall Jobe
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia.,Department of Neonatology, Pulmonary Biology and Pediatrics, Cincinnati Children's Hospital Medical Centre, University of Cincinnati, Cincinnati, OH, United States
| | - Matthew W Kemp
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia.,Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan.,School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.,Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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9
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Takahashi T, Fee EL, Takahashi Y, Saito M, Yaegashi N, Usuda H, Furfaro L, Carter S, Schmidt AF, Newnham JP, Jobe AH, Kemp MW. Betamethasone phosphate reduces the efficacy of antenatal steroid therapy and is associated with lower birthweights when administered to pregnant sheep in combination with betamethasone acetate. Am J Obstet Gynecol 2022; 226:564.e1-564.e14. [PMID: 34626553 DOI: 10.1016/j.ajog.2021.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 10/01/2021] [Accepted: 10/04/2021] [Indexed: 12/25/2022]
Abstract
BACKGROUND Antenatal corticosteroid therapy is a standard of care for women at imminent risk of preterm labor. However, the optimal (maximum benefit and minimal risk of side effects) antenatal corticosteroid dosing strategy remains unclear. Although conveying overall benefit when given to the right patient at the right time, antenatal corticosteroid treatment efficacy is highly variable and is not risk-free. Building on earlier findings, we hypothesized that when administered in combination with slow-release betamethasone acetate, betamethasone phosphate and the high maternal-fetal betamethasone concentrations it generates are redundant for fetal lung maturation. OBJECTIVE Using an established sheep model of prematurity and postnatal ventilation of the preterm lamb, we aimed to compare the pharmacodynamic effects of low-dosage treatment with betamethasone acetate only against a standard dosage of betamethasone phosphate and betamethasone acetate as recommended by the American College of Obstetricians and Gynecologists for women at risk of imminent preterm delivery between 24 0/7 and 35 6/7 weeks' gestation. STUDY DESIGN Ewes carrying a single fetus at 122±1 days' gestation (term=150 days) were randomized to receive either (1) maternal intramuscular injections of sterile saline (the saline negative control group, n=12), (2) 2 maternal intramuscular injections of 0.25 mg/kg betamethasone phosphate+betamethasone acetate administered at 24-hour dosing intervals (the betamethasone phosphate+betamethasone acetate group, n=12); or (3) 2 maternal intramuscular injections of 0.125 mg/kg betamethasone acetate administered at 24-hour dosing intervals (the betamethasone acetate group, n=11). The fetuses were surgically delivered 48 hours after treatment initiation and ventilated for 30 minutes to determine functional lung maturation. The fetuses were euthanized after ventilation, and the lungs were collected for analysis using quantitative polymerase chain reaction and Western blot assays. Fetal plasma adrenocorticotropic hormone levels were measured in the cord blood samples taken at delivery. RESULTS Preterm lambs were defined as either antenatal corticosteroid treatment responders or nonresponders using an arbitrary cutoff, being a PaCO2 level at 30 minutes of ventilation being more extreme than 2 standard deviations from the mean value of the normally distributed saline control group values. Compared with the animals in the saline control group, the animals in the antenatal corticosteroid treatment groups showed significantly improved lung physiological responses (blood gas and ventilation data) and had a biochemical signature (messenger RNA and surfactant protein assays) consistent with functional maturation. However, the betamethasone acetate group had a significantly higher treatment response rate than the betamethasone phosphate+betamethasone acetate group. These physiological results were strongly correlated to the amount of surfactant protein A. Birthweight was lower in the betamethasone phosphate+betamethasone acetate group and the fetal hypothalamic-pituitary-adrenal axis was suppressed to a greater extent in the betamethasone phosphate+betamethasone acetate group. CONCLUSION Low-dosage antenatal corticosteroid therapy solely employing betamethasone acetate was sufficient for fetal lung maturation. The elevated maternal-fetal betamethasone concentrations associated with the coadministration of betamethasone phosphate did not in addition improve lung maturation but were associated with greater fetal hypothalamic-pituitary-adrenal axis suppression, a lower antenatal corticosteroid treatment response rate, and lower birthweight-outcomes not desirable in a clinical setting. These data warranted a clinical investigation of sustained low-dosage antenatal corticosteroid treatments that avoid high maternal-fetal betamethasone exposures.
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Affiliation(s)
- Tsukasa Takahashi
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan.
| | - Erin L Fee
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Yuki Takahashi
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Masatoshi Saito
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Nobuo Yaegashi
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Haruo Usuda
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Lucy Furfaro
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Sean Carter
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Augusto F Schmidt
- Perinatal Research, Department of Pediatrics, Cincinnati Children's Hospital Medical Centre, University of Cincinnati, Cincinnati, OH; Miller School of Medicine, University of Miami, Miami, FL
| | - John P Newnham
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Alan H Jobe
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Perinatal Research, Department of Pediatrics, Cincinnati Children's Hospital Medical Centre, University of Cincinnati, Cincinnati, OH
| | - Matthew W Kemp
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan; School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia; Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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10
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Abstract
Objectives: The purpose of this study was to compare short-term outcomes in children born between 24 and 34 weeks' gestation, according to observed antenatal corticosteroids (ACS)-to-birth intervals. Research question: 'Is there a difference in short-term outcomes between observed ACS-to-birth intervals across a range of gestational ages at birth?'Methods: Cohort study assessing differences in incidence of short-term neonatal outcomes according to the observed interval between the last administration of ACS and birth. Linear, non-weighted GEE models with an independence working correlation structure were fitted to infant level data providing valid point estimates for either incidence or rate differences (binary outcomes) or average differences (continuous outcomes).Results: Of 886 children, 35.9% were born within 2 days after the last administration of ACS, 32.2% within 2 to 7 days, 14.1% within 8 to 14 days, and 17.8% more than 14 days after. Across gestational ages at birth, there were no differences in birth weight between children born at an ACS-to-birth interval of 7 days or less compared to more than 7 days, nor were there differences in respiratory outcomes, cerebral outcomes, or composite outcome.Conclusion: Drawing conclusions on the importance of the ACS-to-birth interval is difficult due to the post-hoc nature of the variable. In the absence of tools to better estimate if and when PTB will occur, it might not have any value in daily practice, regardless of whether there is an optimal ACS-to-birth interval or not.
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Affiliation(s)
- Isabelle Dehaene
- Obstetrics and Gynecology, Ghent University Hospital, Ghent, Belgium
| | - Kris De Coen
- Neonatal Intensive Care Unit, Ghent University Hospital, Ghent, Belgium
| | - Anna Oostra
- Pediatrics, Ghent University Hospital, Ghent, Belgium
| | | | - Kristien Roelens
- Obstetrics and Gynecology, Ghent University Hospital, Ghent, Belgium
| | - Koenraad Smets
- Neonatal Intensive Care Unit, Ghent University Hospital, Ghent, Belgium
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11
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Bayraktar S, Tanyeri Bayraktar B, Kılıç Ü. Umbilical cord levels of macrophage migration inhibitory factor in neonatal respiratory distress syndrome. Turk J Med Sci 2021; 51:722-726. [PMID: 33356032 PMCID: PMC8203148 DOI: 10.3906/sag-2008-113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 12/26/2020] [Indexed: 11/03/2022] Open
Abstract
Background/aim We aimed to evaluate the association of the umbilical cord macrophage migration inhibitory factor (MIF) with the
respiratory distress syndrome (RDS) in preterm infants. Materials and methods A total of eighty six preterm infants (38 with RDS and 48 without RDS) were involved in the study. ELISA is the technique assaying MIF values. Results The mean of the infants’ gestational ages and birth weights were significantly different (P = 0.0001). There were no significant differences in sex, delivery mode or exposure to antenatal steroid among the groups (P > 0.05). Umbilical cord MIF levels of the infants were not correlated with gestational age and birth weight (Spearman’s rho = –0.22 and 0.28 respectively, P > 0.05). There was no statistically significant difference in umbilical cord MIF levels of infants whether or not they were administered antenatal steroid (median:17.88 vs. median:17.60, Mann–Whitney U test, P = 0.42). Cord serum MIF levels were higher (mean, 17.09 ± 5.86 ng/mL) in the RDS group than in the non-RDS group (mean, 14.72 ± 4.18 ng/mL) (P = 0.005). Conclusion This study shows that, MIF level is higher in the cord blood of the infants with RDS than of the infants without RDS. This supports that MIF expression begins in prior to the birth of the preterm infants and MIF has enhancing impact on the lung development of premature babies. With future studies, the assessment of the cord MIF levels at the bedside may be beneficial for the diagnosis and treatment of RDS, and taking actions to prevent long-term consequences.
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Affiliation(s)
- Süleyman Bayraktar
- Department of Pediatric Intensive Care, Bezmiâlem Vakıf University, İstanbul, Turkey
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12
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Takahashi T, Saito M, Schmidt AF, Usuda H, Takahashi Y, Watanabe S, Hanita T, Sato S, Kumagai Y, Koshinami S, Ikeda H, Carter S, Clarke M, Fee EL, Yaegashi N, Newnham JP, Jobe AH, Kemp MW. Variability in the efficacy of a standardized antenatal steroid treatment was independent of maternal or fetal plasma drug levels: evidence from a sheep model of pregnancy. Am J Obstet Gynecol 2020; 223:921.e1-921.e10. [PMID: 32445634 DOI: 10.1016/j.ajog.2020.05.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 05/05/2020] [Accepted: 05/14/2020] [Indexed: 11/23/2022]
Abstract
BACKGROUND Administration of antenatal steroids is standard of care for women assessed to be at imminent risk of preterm delivery. There is a marked variation in antenatal steroid dosing strategy, selection for treatment criteria, and agent choice worldwide. This, combined with very limited optimization of antenatal steroid use per se, means that treatment efficacy is highly variable, and the rate of respiratory distress syndrome is decreased to perhaps as low as 40%. In some cases, antenatal steroid use is associated with limited benefit and potential harm. OBJECTIVE We hypothesized that individual differences in maternofetal steroid exposure would contribute to observed variability in antenatal steroid treatment efficacy. Using a chronically catheterized sheep model of pregnancy, we aimed to explore the relationship between maternofetal steroid exposure and antenatal steroid treatment efficacy as determined by functional lung maturation in preterm lambs undergoing ventilation. STUDY DESIGN Ewes carrying a single fetus underwent surgery to catheterize a fetal and maternal jugular vein at 119 days' gestation. Animals recovered for 24 hours before being randomized to either (1) a single maternal intramuscular injection of 2 mL saline (negative control group, n=10) or (2) a single maternal intramuscular injection of 0.25 mg/kg betamethasone phosphate plus acetate (antenatal steroid group, n=20). Serial maternal and fetal plasma samples were collected from each animal after 48 hours before fetuses were delivered and ventilated for 30 minutes. Total and free plasma betamethasone concentration was measured by mass spectrometry. Fetal lung tissue was collected for analysis using quantitative polymerase chain reaction. RESULTS One animal from the control group and one animal from the antenatal steroid group did not complete their treatment protocol and were removed from analyses. Animals in the antenatal steroid group were divided into a responder subgroup (n=12/19) and a nonresponder subgroup (n=7/19) using a cutoff of partial pressure of arterial CO2 at 30-minute ventilation within 2 standard deviations of the mean value from saline-treated negative control group animals. Although antenatal steroid improved fetal lung maturation in the undivided antenatal steroid group and in the responder subgroup both physiologically (blood gas- and ventilation-related data) and biochemically (messenger ribonucleic acid expression related to fetal lung maturation), these values did not improve relative to saline-treated control group animals in the antenatal steroid nonresponder subgroup. No differences in betamethasone distribution, clearance, or protein binding were identified between the antenatal steroid responder and nonresponder subgroups. CONCLUSION This study correlated individual maternofetal steroid exposures with preterm lung maturation as determined by pulmonary ventilation. Herein, approximately 40% of preterm lambs exposed to antenatal steroids had lung maturation that was not significantly different to saline-treated control group animals. These nonresponsive animals received maternal and fetal betamethasone exposures identical to animals that had a significant improvement in functional lung maturation. These data suggest that the efficacy of antenatal steroid therapy is not solely determined by maternofetal drug levels and that individual fetal or maternal factors may play a role in determining treatment outcomes in response to glucocorticoid signaling.
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13
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Bozkaya D, Korkmaz Toygar A, Turgal M, Ozyuncu O, Yigit S, Yurdakok M. Is chlorine and sodium levels in the amniotic fluid a new marker for fetal lung maturation and RDS severity? J Matern Fetal Neonatal Med 2020; 35:3998-4003. [PMID: 33231495 DOI: 10.1080/14767058.2020.1846179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND Amniotic fluid (AF) is a dynamic liquid whose contents vary according to the needs of the fetus. Levels of the amniotic components have been used in numerous studies as potential biomarkers to screen pregnancy-related abnormalities. As a reflection of Na+ and Cl- levels of fetal lung fluid, amniotic fluid's Na+ and Cl- levels can be used as an indicator of lung maturation in the newborn period. This study aimed to investigate whether Na+ and Cl- levels in the amniotic fluid would be a new marker to determine the severity of respiratory distress and pulmonary maturation in the newborn. METHODS This prospective cohort study was conducted at Hacettepe University Neonatal Intensive Care Unit. One hundred twenty single infants who were delivered with the cesarean section between January 2015 and March 2016 were included. Na+ and Cl- levels were measured from AF. RESULTS There were 46 of 120 infants (33.3%) in Group-1 and 74 infants (66.7%) in Group-2. Na + and Cl- levels of the AF of Group-1 were higher than Group 2 and this was statistically significant (p < .001/p: .01, respectively). Na+ and Cl- levels of the AF were significantly higher in infants who needed surfactant (p < .001/p: .001, respectively). CONCLUSION Our results showed that Na+ and Cl- levels of the AF can be used as an indicator of infant lung maturation.
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Affiliation(s)
- Davut Bozkaya
- Department of Neonatology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Ayse Korkmaz Toygar
- Department of Neonatology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Mert Turgal
- Koç University School of Medicine, Department of Obstetrics and Gynecology, Section of Perinatology, Istanbul, Turkey
| | - Ozgur Ozyuncu
- Department of Obstetrics and Gynecology, Hacettepe University School of Medicine, Ankara, Turkey
| | - Sule Yigit
- Department of Neonatology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Murat Yurdakok
- Department of Neonatology, Hacettepe University Faculty of Medicine, Ankara, Turkey
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14
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Kemp MW, Saito M, Schmidt AF, Usuda H, Watanabe S, Sato S, Hanita T, Kumagai Y, Takahashi T, Musk GC, Furfaro L, Stinson L, Fee EL, Eddershaw PJ, Payne MS, Smallwood K, Bridges J, Newnham JP, Jobe AH. The duration of fetal antenatal steroid exposure determines the durability of preterm ovine lung maturation. Am J Obstet Gynecol 2020; 222:183.e1-183.e9. [PMID: 31494126 DOI: 10.1016/j.ajog.2019.08.046] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/14/2019] [Accepted: 08/23/2019] [Indexed: 01/05/2023]
Abstract
BACKGROUND Antenatal corticosteroids (ACS) are the standard of care for maturing the fetal lung and improving outcomes for preterm infants. Antenatal corticosteroid dosing remains nonoptimized, and there is little understanding of how different treatment-to-delivery intervals may affect treatment efficacy. The durability of a lung maturational response is important because the majority of women treated with antenatal corticosteroids do not deliver within the widely accepted 1- to 7-day window of treatment efficacy. OBJECTIVE We used a sheep model to test the duration of fetal exposures for efficacy at delivery intervals from 1 to 10 days. MATERIALS AND METHODS For infusion studies, ewes with single fetuses were randomized to receive an intravenous bolus and maintenance infusion of betamethasone phosphate to target 1-4 ng/mL fetal plasma betamethasone for 36 hours, with delivery at 2, 4 ,or 7 days posttreatment or sterile saline solution as control. Animals receiving the clinical treatment were randomised to receive either a single injection of 0.25 mg/kg with a 1:1 mixture of betamethasone phosphate + betamethasone acetate with delivery at either 1 or 7 days posttreatment, or 2 treatments of 0.25 mg/kg betamethasone phosphate + betamethasone acetate spaced at 24 hours (giving ∼48 hours of fetal steroid exposure) with delivery at 2, 5, 7, or 10 days posttreatment. Negative control animals were treated with saline solution. All lambs were delivered at 121 ± 3 days gestational age and ventilated for 30 minutes to assess lung function. RESULTS Preterm lambs delivered at 1 or 2 days post-antenatal corticosteroid treatment had significant improvements in lung maturation for both intravenous and single-dose intramuscular treatments. After 2 days, the efficacy of 36-hour betamethasone phosphate infusions was lost. The single dose of 1:1 betamethasone phosphate + betamethasone acetate also was ineffective at 7 days. In contrast, animals treated with 2 doses had significant improvements in lung maturation at 2, 5, and 7 days, with treatment efficacy reduced by 10 days. CONCLUSION In preterm lambs, the durability of antenatal corticosteroids treatment depends on the duration of fetal exposure and is independent of the intravenous or intramuscular maternal route of administration. For acute 24- to 48-hour posttreatment deliveries, a 24-hour fetal antenatal corticosteroids exposure was sufficient for lung maturation. A fetal exposure duration of at least 48 hours was necessary to maintain long-term treatment durability. A single-dose ACS treatment should be sufficient for women delivering within <48 hours of antenatal corticosteroids treatment.
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Affiliation(s)
- Matthew W Kemp
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan; School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia.
| | - Masatoshi Saito
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | | | - Haruo Usuda
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Shimpei Watanabe
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Shinichi Sato
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Takushi Hanita
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Yusaku Kumagai
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Tsukasa Takahashi
- Centre for Perinatal and Neonatal Medicine, Tohoku University Hospital, Sendai, Japan
| | - Gabrielle C Musk
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Lucy Furfaro
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Lisa Stinson
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Erin L Fee
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | | | - Matthew S Payne
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Kiara Smallwood
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - James Bridges
- Cincinnati Children's Hospital Medical Centre, Cincinnati, OH
| | - John P Newnham
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia
| | - Alan H Jobe
- Division of Obstetrics and Gynaecology, The University of Western Australia, Perth, Western Australia, Australia; Cincinnati Children's Hospital Medical Centre, Cincinnati, OH
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15
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Abstract
The physiological changes that occur during pregnancy include altered regulation of the hypothalamo-pituitary-adrenal axis. The fetoplacental unit plays a major role in this, together with alteration of circulating cortisol-binding globulin levels, with a net effect to increase both total and free cortisol levels. Importantly, there are several pathological conditions that require steroid treatment or replacement during pregnancy, and optimizing therapy is clearly crucial. The potential for acute and chronic adverse effects that can impact upon both the mother and the fetus makes the decision of how and when to instigate steroid therapy particularly challenging. In this review, we describe the physio-pathological changes to the hypothalamo-pituitary-adrenal axis that occur during pregnancy, tools to assess endogenous glucocorticoid reserve as well as discuss treatment strategies and the potential for the development of adverse events.
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Affiliation(s)
- Riccardo Pofi
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy.,Oxford Centre for Diabetes, Endocrinology and Metabolism, NIHR Oxford Biomedical Research Centre, University of Oxford, Churchill Hospital, Oxford, UK
| | - Jeremy W Tomlinson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, NIHR Oxford Biomedical Research Centre, University of Oxford, Churchill Hospital, Oxford, UK
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16
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Kemp MW, Saito M, Usuda H, Watanabe S, Sato S, Hanita T, Kumagai Y, Molloy TJ, Clarke M, Eddershaw PJ, Musk GC, Schmidt A, Ireland D, Furfaro L, Payne MS, Newnham JP, Jobe AH. The efficacy of antenatal steroid therapy is dependent on the duration of low-concentration fetal exposure: evidence from a sheep model of pregnancy. Am J Obstet Gynecol 2018; 219:301.e1-301.e16. [PMID: 29758177 DOI: 10.1016/j.ajog.2018.05.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/20/2018] [Accepted: 05/03/2018] [Indexed: 11/27/2022]
Abstract
BACKGROUND Antenatal corticosteroids are among the most important and widely used interventions to improve outcomes for preterm infants. Antenatal corticosteroid dosing regimens remain unoptimized and without maternal weight-adjusted dosing. We, and others, have hypothesized that, once a low concentration of maternofetal steroid exposure is achieved and maintained, the duration of the steroid exposure determines treatment efficacy. Using a sheep model of pregnancy, we tested the relationship among steroid dose, duration of exposure, and treatment efficacy. OBJECTIVE The study was conducted to investigate the relative importance of duration and magnitude of fetal corticosteroid exposure to mature the preterm fetal ovine lung. STUDY DESIGN Ewes with single fetuses at 120 days gestation received an intravenous bolus (loading dose) followed by a maintenance infusion of betamethasone phosphate to target 12-hour fetal plasma betamethasone concentrations of (1) 20 ng/mL, (2) 10 ng/mL, or (3) 2 ng/mL. In a subsequent experiment, fetal plasma betamethasone concentrations were targeted at 2 ng/mL for 26 hours. Negative control animals received sterile saline solution. Positive control animals received 2 intramuscular injections of 0.25 mg/kg Celestone Chronodose (betamethasone phosphate + betamethasone acetate) spaced at 24 hours. Preterm lambs were delivered surgically and ventilated 48 hours after treatment commenced. Maternal and fetal plasma betamethasone concentrations were confirmed by mass spectrometry in a parallel study of chronically catheterized, corticosteroid-treated ewes and fetuses. RESULTS The loading and maintenance doses were achieved and maintained the desired fetal plasma betamethasone concentrations of approximately 20, 10, and 2 ng/mL for 12 hours. Compared with the 12-hour infusion-treated animals, lambs from the positive control (2 intramuscular doses of 0.25 mg/kg Celestone Chronodose) group had the greatest functional lung maturation (compliance, gas exchange, arterial pH) and molecular evidence of maturation (glucocorticoid receptor signaling activation), despite having maximum fetal plasma betamethasone concentrations 2.5 times lower than animals in the 20 ng/mL betamethasone infusion group. Lambs from the 12-hour 2-ng/mL betamethasone infusion group had little functional lung maturation. In contrast, lambs from the 26-hour 2-ng/mL betamethasone infusion group had functional lung maturation equivalent to lambs from the positive control group. CONCLUSION In preterm lambs that were exposed to antenatal corticosteroids, high maternofetal plasma betamethasone concentrations did not correlate with improved lung maturation. The largest and most consistent improvements in lung maturation were in animals that were exposed to either the clinical course of Celestone Chronodose or a low-dose betamethasone phosphate infusion to achieve a fetal plasma betamethasone concentration of approximately 2 ng/mL for 26 hours. The duration of low-concentration maternofetal steroid exposure, not total dose or peak drug exposure, is a key determinant for antenatal corticosteroids efficacy. These findings underscore the need to develop an optimized steroid dosing regimen that may improve both the efficacy and safety of antenatal corticosteroids therapy.
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17
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Lee MK, Smith SM, Banerjee MM, Li C, Minoo P, Volpe MV, Nielsen HC. The p66Shc adapter protein regulates the morphogenesis and epithelial maturation of fetal mouse lungs. Am J Physiol Lung Cell Mol Physiol 2013; 306:L316-25. [PMID: 24375794 DOI: 10.1152/ajplung.00062.2013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Many signaling pathways are mediated by Shc adapter proteins that, in turn, are expressed as three isoforms with distinct functions. The p66(Shc) isoform antagonizes proliferation, regulates oxidative stress, and mediates apoptosis. It is highly expressed in the canalicular but not the later stages of mouse lung development, and its expression persists in bronchopulmonary dysplasia, a chronic disease associated with premature birth. These observations suggest that p66(Shc) has a developmental function. However, constitutive p66(Shc) deletion yields no morphological phenotype, and the structure of the Shc gene precludes its inducible deletion. To elucidate its function in lung development, we transfected p66(Shc) or nonsilencing small-interfering RNA (siRNA) into the epithelia of embryonic day 11 mouse lungs that were then cultured for 3 days and analyzed morphometrically. To assess cellular proliferation and epithelial differentiation, lung explants were immunostained and immunoblotted for p66(Shc), proliferating cell nuclear antigen (PCNA), the proximal airway differentiation antigens Clara cell 10-kDa protein (CC10) and thyroid transcription factor (TTF)-1, and the alveolar surfactant proteins (SP)-A, -B, and -C. Explants transfected with nonsilencing siRNA demonstrated specific epithelial uptake and normal morphological development relative to uninjected controls. In contrast, transfection with p66(Shc) siRNA significantly increased lumenal cross-sectional areas, decreased branching, and increased epithelial proliferation (P < 0.05 for all). Relative to controls, the expression of SP-B, SP-C, CC10, and TTF-1 was decreased by p66(Shc) knockdown. SP-A was not expressed in either control or treated lungs. These data suggest that p66(Shc) attenuates epithelial proliferation while promoting both distal and proximal epithelial maturation.
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Affiliation(s)
- M K Lee
- General Laboratories Bldg., 1201 E. Marengo St., Los Angeles, CA 90033.
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18
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Antalyalı M, Ozmen O, Halıgür M, Sezik M. Fetal pulmonary injury following single high-dose intra-amniotic betamethasone treatment in preterm goat kids. J Turk Ger Gynecol Assoc 2012; 13:242-6. [PMID: 24592050 DOI: 10.5152/jtgga.2012.38] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2012] [Accepted: 10/03/2012] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE Fetal lung maturation is an extremely important process that is necessary for the survival of the neonates. Conventionally, corticosteroids are administered maternally for inducing fetal lung maturation in preterm fetuses. Alternatively, single-dose intra-amniotic (IA) treatment might be speculated to improve lung maturity. In the goat model, we recently showed that high-dose IA betamethasone (BM) was associated with an increased number of stillbirths and emphysematous changes. The aim of the present study is to expand our previous findings and evaluate the histopathological effects of IA injection of a single high-dose of BM 48 h before induced preterm delivery, using our previously collected specimens. MATERIAL AND METHODS Five hair goat fetal lungs that had received 8 mg/kg IA BM at gestational day 118 (term, 150 days) and scheduled for preterm delivery by cesarean section at day 120 of gestation were examined pathologically. Specimens were stained with hematoxylin and eosin (HE) and were interpreted by light microscopy. RESULTS The histopathological examination of the fetal lungs revealed edema, hemorrhage, slight inflammatory reaction, marked emphysema, and desquamation of the pneumocytes and bronchiolar or bronchial epithelial cells. CONCLUSION High-dose IA BM administrations to induce lung maturation can paradoxically cause severe pathological lesions in the fetal lungs. These might explain the toxic effects we encountered with this mode of treatment.
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Affiliation(s)
- Meltem Antalyalı
- Department of Gynecology and Obstetrics, Faculty of Medicine, Süleyman Demirel University, Isparta, Turkey
| | - Ozlem Ozmen
- Department of Pathology, Faculty of Veterinary Medicine, Mehmet Akif Ersoy University, Burdur, Turkey
| | - Mehmet Halıgür
- Department of Pathology, Faculty of Veterinary Medicine, Mehmet Akif Ersoy University, Burdur, Turkey
| | - Mekin Sezik
- Department of Gynecology and Obstetrics, Faculty of Medicine, Süleyman Demirel University, Isparta, Turkey
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Abstract
Very preterm infants are commonly exposed to a chronic, often asymptomatic, chorioamnionitis that is diagnosed by histologic evaluation of the placenta only after delivery. The reported effects of these exposures on fetal lungs are inconsistent because exposure to different organisms, durations of exposure, and fetal/maternal responses affect outcomes. In experimental models, chorioamnionitis can both injure and mature the fetal lung and cause immune nodulation. Postnatal care strategies also change how chorioamnionitis relates to clinical outcomes such as bronchopulmonary dysplasia.
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Affiliation(s)
- Alan Jobe
- Cincinnati Children’s Hospital Medical Center, Division of Pulmonary Biology, University of Cincinnati, Cincinnati, OH
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Carlo WA, McDonald SA, Fanaroff AA, Vohr BR, Stoll BJ, Ehrenkranz RA, Andrews WW, Wallace D, Das A, Bell EF, Walsh MC, Laptook AR, Shankaran S, Poindexter BB, Hale EC, Newman NS, Davis AS, Schibler K, Kennedy KA, Sánchez PJ, Van Meurs KP, Goldberg RN, Watterberg KL, Faix RG, Frantz ID, Higgins RD. Association of antenatal corticosteroids with mortality and neurodevelopmental outcomes among infants born at 22 to 25 weeks' gestation. JAMA 2011; 306:2348-58. [PMID: 22147379 PMCID: PMC3565238 DOI: 10.1001/jama.2011.1752] [Citation(s) in RCA: 244] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Current guidelines, initially published in 1995, recommend antenatal corticosteroids for mothers with preterm labor from 24 to 34 weeks' gestational age, but not before 24 weeks due to lack of data. However, many infants born before 24 weeks' gestation are provided intensive care. OBJECTIVE To determine if use of antenatal corticosteroids is associated with improvement in major outcomes for infants born at 22 and 23 weeks' gestation. DESIGN, SETTING, AND PARTICIPANTS Cohort study of data collected prospectively on inborn infants with a birth weight between 401 g and 1000 g (N = 10,541) born at 22 to 25 weeks' gestation between January 1, 1993, and December 31, 2009, at 23 academic perinatal centers in the United States. Certified examiners unaware of exposure to antenatal corticosteroids performed follow-up examinations on 4924 (86.5%) of the infants born between 1993 and 2008 who survived to 18 to 22 months. Logistic regression models generated adjusted odds ratios (AORs), controlling for maternal and neonatal variables. MAIN OUTCOME MEASURES Mortality and neurodevelopmental impairment at 18 to 22 months' corrected age. RESULTS Death or neurodevelopmental impairment at 18 to 22 months was significantly lower for infants who had been exposed to antenatal corticosteroids and were born at 23 weeks' gestation (83.4% with exposure to antenatal corticosteroids vs 90.5% without exposure; AOR, 0.58 [95% CI, 0.42-0.80]), at 24 weeks' gestation (68.4% with exposure to antenatal corticosteroids vs 80.3% without exposure; AOR, 0.62 [95% CI, 0.49-0.78]), and at 25 weeks' gestation (52.7% with exposure to antenatal corticosteroids vs 67.9% without exposure; AOR, 0.61 [95% CI, 0.50-0.74]) but not in those infants born at 22 weeks' gestation (90.2% with exposure to antenatal corticosteroids vs 93.1% without exposure; AOR, 0.80 [95% CI, 0.29-2.21]). If the mothers had received antenatal corticosteroids, the following events occurred significantly less in infants born at 23, 24, and 25 weeks' gestation: death by 18 to 22 months; hospital death; death, intraventricular hemorrhage, or periventricular leukomalacia; and death or necrotizing enterocolitis. For infants born at 22 weeks' gestation, the only outcome that occurred significantly less was death or necrotizing enterocolitis (73.5% with exposure to antenatal corticosteroids vs 84.5% without exposure; AOR, 0.54 [95% CI, 0.30-0.97]). CONCLUSION Among infants born at 23 to 25 weeks' gestation, antenatal exposure to corticosteroids compared with nonexposure was associated with a lower rate of death or neurodevelopmental impairment at 18 to 22 months.
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Affiliation(s)
- Waldemar A Carlo
- Department of Pediatrics, University of Alabama, 9380 Women and Infants Center, 1700 Sixth Ave S, Birmingham, AL 35249, USA.
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Ross AC, Ambalavanan N. Retinoic acid combined with vitamin A synergizes to increase retinyl ester storage in the lungs of newborn and dexamethasone-treated neonatal rats. Neonatology 2007; 92:26-32. [PMID: 17596734 PMCID: PMC3843127 DOI: 10.1159/000100083] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Accepted: 09/25/2006] [Indexed: 12/22/2022]
Abstract
BACKGROUND Retinyl esters (REs), the major storage form of vitamin A (retinol), provide substrates for the production of bioactive retinoids, including retinoic acid (RA), which are known to promote lung development and maturation. We previously showed that the nutrient-metabolite combination VARA (molar ratio 10 vitamin A to 1 RA), synergistically increased REs in the lungs of 1-week-old rats, compared to vitamin A or RA alone. OBJECTIVES To test the hypotheses, first, that VARA is more effective in increasing lung RE than is vitamin A in newborn rats prior to alveolarization, and, second, that the effect of VARA is maintained during concurrent treatment with the glucocorticoid, dexamethasone (Dex). METHODS Newborn rats were treated with VARA, vitamin A alone, or oil (C) on postnatal days (P) 1-3, and RE in the lungs was quantified on P4, and again on P8 to assess retention. Additionally, neonatal rats were treated on P5-7 with VARA with and without Dex, and the lung and liver REs were quantified on P8. RESULTS AND CONCLUSIONS Lung RE was nearly 8-fold higher in VARA compared to vitamin A-treated rats on P4 (p < 0.01) and 2.5-fold higher on P8. In neonates co-treated with Dex and VARA on P5-7, the elevation in lung RE on P8 by VARA was not antagonized by Dex, although Dex reduced growth. Lung morphology and development were not significantly altered. The VARA combination may significantly increase lung RE content even during concurrent Dex therapy. Because lung retinoids are important for lung maturation and repair, increasing lung RE may possibly have clinical benefit.
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Affiliation(s)
- A Catharine Ross
- Department of Nutritional Sciences and Huck Institute for Life Sciences, Pennsylvania State University, University Park, PA 16802, USA
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