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Akalay S, Rayyan M, Fidlers T, van den Heuvel L, Levtchenko E, Arcolino FO. Impact of preterm birth on kidney health and development. Front Med (Lausanne) 2024; 11:1363097. [PMID: 38601116 PMCID: PMC11004308 DOI: 10.3389/fmed.2024.1363097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 03/14/2024] [Indexed: 04/12/2024] Open
Abstract
Preterm birth, defined as birth before the gestational age of 37 weeks, affects 11% of the newborns worldwide. While extensive research has focused on the immediate complications associated with prematurity, emerging evidence suggests a link between prematurity and the development of kidney disease later in life. It has been demonstrated that the normal course of kidney development is interrupted in infants born prematurely, causing an overall decrease in functional nephrons. Yet, the pathogenesis leading to the alterations in kidney development and the subsequent pathophysiological consequences causing kidney disease on the long-term are incompletely understood. In the present review, we discuss the current knowledge on nephrogenesis and how this process is affected in prematurity. We further discuss the epidemiological evidence and experimental data demonstrating the increased risk of kidney disease in these individuals and highlight important knowledge gaps. Importantly, understanding the intricate interplay between prematurity, abnormal kidney development, and the long-term risk of kidney disease is crucial for implementing effective preventive and therapeutic strategies.
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Affiliation(s)
- Sara Akalay
- Department of Development and Regeneration, Katholieke Universiteit Leuven, Leuven, Belgium
- Department of Nephrology, Dialysis and Renal Transplantation, University Hospitals Leuven, Leuven, Belgium
| | - Maissa Rayyan
- Department of Development and Regeneration, Katholieke Universiteit Leuven, Leuven, Belgium
- Neonatal Intensive Care Unit, University Hospitals Leuven, Leuven, Belgium
| | - Tom Fidlers
- Department of Gynecologic Oncology, Oscar Lambret Cancer Center, Lille, France
| | - Lambertus van den Heuvel
- Department of Development and Regeneration, Katholieke Universiteit Leuven, Leuven, Belgium
- Department of Pediatric Nephrology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Elena Levtchenko
- Department of Pediatric Nephrology, Emma Children’s Hospital, Amsterdam University Medical Centers, Amsterdam, Netherlands
| | - Fanny Oliveira Arcolino
- Department of Pediatric Nephrology, Emma Children’s Hospital, Amsterdam University Medical Centers, Amsterdam, Netherlands
- Emma Center for Personalized Medicine, Amsterdam University Medical Centers, Amsterdam, Netherlands
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Sutherland MR, Black MJ. The impact of intrauterine growth restriction and prematurity on nephron endowment. Nat Rev Nephrol 2023; 19:218-228. [PMID: 36646887 DOI: 10.1038/s41581-022-00668-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2022] [Indexed: 01/18/2023]
Abstract
In humans born at term, maximal nephron number is reached by the time nephrogenesis is completed - at approximately 36 weeks' gestation. The number of nephrons does not increase further and subsequently remains stable until loss occurs through ageing or disease. Nephron endowment is key to the functional capacity of the kidney and its resilience to disease; hence, any processes that impair kidney development in the developing fetus can have lifelong adverse consequences for renal health and, consequently, for quality and length of life. The timing of nephrogenesis underlies the vulnerability of developing human kidneys to adverse early life exposures. Indeed, exposure of the developing fetus to a suboptimal intrauterine environment during gestation - resulting in intrauterine growth restriction (IUGR) - and/or preterm birth can impede kidney development and lead to reduced nephron endowment. Furthermore, emerging research suggests that IUGR and/or preterm birth is associated with an elevated risk of chronic kidney disease in later life. The available data highlight the important role of early life development in the aetiology of kidney disease and emphasize the need to develop strategies to optimize nephron endowment in IUGR and preterm infants.
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Affiliation(s)
- Megan R Sutherland
- Department of Anatomy and Developmental Biology and Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Mary Jane Black
- Department of Anatomy and Developmental Biology and Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
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3
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Garcia Kako Rodriguez M, Correia Santos VJ, Ramirez Uscategui RA, Gomes Mariano RS, Rodrigues Simões AP, Del Aguila da Silva P, Maronezi MC, Padilha-Nakaghi LC, Lopes Avante M, M Bartlewski P, Rossi Feliciano MA. Maternal and fetal ultrasonographic characteristics, vulvar temperature, and vaginal mucous impedance as variables associated with the onset of parturition in term and induced pre-term ewes. Anim Reprod Sci 2020; 223:106647. [PMID: 33220617 DOI: 10.1016/j.anireprosci.2020.106647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 11/28/2022]
Abstract
The aim of this study was to assess and compare ultrasonographic characteristics of maternal and fetal structures, vulvar temperatures, and vaginal mucous impedance in pregnant ewes in the term parturition group (TPG, n = 15) and induced pre-term parturition group (IPPG; n = 15). All the measurements were taken every 12 h throughout the last gestational week. Maternal and fetal structures and the fetal heart rate (HR) were assessed using ultrasonography. The vulvar temperature and vaginal mucous impedance were determined using a non-contact infrared thermometer, and an electronic estrous detector, respectively. The vulvar temperature was less in the TPG and greater in the IPPG; the end-diastolic velocities (EDVs) of the arteries of the placentome and uterus gradually increased before parturition in the IPPG (P = 0.02, P = 0.02 and P = 0.009, respectively). The placentome shear wave velocity (SWV) was greater in the ewes of the IPPG than TPG 48, 36, and 0 h before parturition (P = 0.001). The following variables were associated with the onset of parturition within the next 12 h in the ewes of the IPPG: resistance index (< 0.54) and EDV (> 0.34 cm/s) of the uterine artery; and vulvar temperature (> 37.3 °C). A fetal kidney SWV of < 1.31 m/s was associated with the onset of parturition in the next 12 h in all the ewes. Results indicate vulvar temperature and certain maternal and fetal factors detected using ultrasonograpy may aid in determining fetal maturity and/or the time of parturition in ewes.
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Affiliation(s)
- Mariana Garcia Kako Rodriguez
- Department of Animal Reproduction, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Victor José Correia Santos
- Department of Animal Reproduction, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Ricardo Andres Ramirez Uscategui
- Institute of Agricultural Sciences, Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), 38610-000, Unaí, Minas Gerais, Brazil.
| | - Renata Sitta Gomes Mariano
- Department of Animal Reproduction, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Ana Paula Rodrigues Simões
- Department of Animal Reproduction, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Priscila Del Aguila da Silva
- Department of Animal Reproduction, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Marjury Cristina Maronezi
- Department of Veterinary Surgery, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Luciana Cristina Padilha-Nakaghi
- Department of Animal Reproduction, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Michele Lopes Avante
- Department of Veterinary Surgery, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil.
| | - Pawel M Bartlewski
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, N1G 2W1, Guelph, Ontario, Canada.
| | - Marcus Antônio Rossi Feliciano
- Department of Animal Reproduction, Faculdade de Ciências Agrárias e Veterinárias, Univ. Estadual Paulista "Júlio de Mesquita Filho" (FCAV/UNESP), 14884-900, Jaboticabal, São Paulo, Brazil; Department of Large Animals Clinic and Surgery, Universidade Federal de Santa Maria (UFSM), 97105-900, Santa Maria, Rio Grande do Sul, Brazil.
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Charlton JR, Boohaker L, Askenazi D, Brophy PD, D'Angio C, Fuloria M, Gien J, Griffin R, Hingorani S, Ingraham S, Mian A, Ohls RK, Rastogi S, Rhee CJ, Revenis M, Sarkar S, Smith A, Starr M, Kent AL. Incidence and Risk Factors of Early Onset Neonatal AKI. Clin J Am Soc Nephrol 2019. [PMID: 34497098 DOI: 10.2215/cjn.03670318.2019.2.test] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Neonatal AKI is associated with poor short- and long-term outcomes. The objective of this study was to describe the risk factors and outcomes of neonatal AKI in the first postnatal week. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS The international retrospective observational cohort study, Assessment of Worldwide AKI Epidemiology in Neonates (AWAKEN), included neonates admitted to a neonatal intensive care unit who received at least 48 hours of intravenous fluids. Early AKI was defined by an increase in serum creatinine >0.3 mg/dl or urine output <1 ml/kg per hour on postnatal days 2-7, the neonatal modification of Kidney Disease: Improving Global Outcomes criteria. We assessed risk factors for AKI and associations of AKI with death and duration of hospitalization. RESULTS Twenty-one percent (449 of 2110) experienced early AKI. Early AKI was associated with higher risk of death (adjusted odds ratio, 2.8; 95% confidence interval, 1.7 to 4.7) and longer duration of hospitalization (parameter estimate: 7.3 days 95% confidence interval, 4.7 to 10.0), adjusting for neonatal and maternal factors along with medication exposures. Factors associated with a higher risk of AKI included: outborn delivery; resuscitation with epinephrine; admission diagnosis of hyperbilirubinemia, inborn errors of metabolism, or surgical need; frequent kidney function surveillance; and admission to a children's hospital. Those factors that were associated with a lower risk included multiple gestations, cesarean section, and exposures to antimicrobials, methylxanthines, diuretics, and vasopressors. Risk factors varied by gestational age strata. CONCLUSIONS AKI in the first postnatal week is common and associated with death and longer duration of hospitalization. The AWAKEN study demonstrates a number of specific risk factors that should serve as "red flags" for clinicians at the initiation of the neonatal intensive care unit course. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER Assessment of Worldwide AKI Epidemiology in Neonates (AWAKEN), NCT02443389.
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Affiliation(s)
| | - Louis Boohaker
- University of Alabama at Birmingham, Birmingham, Alabama
| | - David Askenazi
- University of Alabama at Birmingham, Birmingham, Alabama
| | - Patrick D Brophy
- Golisano Children's Hospital, University of Rochester, Rochester, New York
| | - Carl D'Angio
- Golisano Children's Hospital, University of Rochester, Rochester, New York
| | - Mamta Fuloria
- Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York
| | - Jason Gien
- Children's Hospital Colorado, University of Colorado, Aurora, Colorado
| | | | - Sangeeta Hingorani
- Seattle Children's Hospital/University of Washington, Seattle, Washington
| | - Susan Ingraham
- Kapi'olani Medical Center for Women and Children, Honolulu, Hawaii
| | - Ayesa Mian
- Golisano Children's Hospital, University of Rochester, Rochester, New York
| | - Robin K Ohls
- University of New Mexico, Albuquerque, New Mexico
| | | | | | - Mary Revenis
- Children's National Medical Center, The George Washington University School of Medicine and The Health Sciences, Washington, DC
| | - Subrata Sarkar
- C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan; and
| | | | - Michelle Starr
- Seattle Children's Hospital/University of Washington, Seattle, Washington
| | - Alison L Kent
- Golisano Children's Hospital, University of Rochester, Rochester, New York
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5
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Charlton JR, Boohaker L, Askenazi D, Brophy PD, D'Angio C, Fuloria M, Gien J, Griffin R, Hingorani S, Ingraham S, Mian A, Ohls RK, Rastogi S, Rhee CJ, Revenis M, Sarkar S, Smith A, Starr M, Kent AL. Incidence and Risk Factors of Early Onset Neonatal AKI. Clin J Am Soc Nephrol 2019; 14:184-195. [PMID: 31738181 PMCID: PMC6390916 DOI: 10.2215/cjn.03670318] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 10/05/2018] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Neonatal AKI is associated with poor short- and long-term outcomes. The objective of this study was to describe the risk factors and outcomes of neonatal AKI in the first postnatal week. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS The international retrospective observational cohort study, Assessment of Worldwide AKI Epidemiology in Neonates (AWAKEN), included neonates admitted to a neonatal intensive care unit who received at least 48 hours of intravenous fluids. Early AKI was defined by an increase in serum creatinine >0.3 mg/dl or urine output <1 ml/kg per hour on postnatal days 2-7, the neonatal modification of Kidney Disease: Improving Global Outcomes criteria. We assessed risk factors for AKI and associations of AKI with death and duration of hospitalization. RESULTS Twenty-one percent (449 of 2110) experienced early AKI. Early AKI was associated with higher risk of death (adjusted odds ratio, 2.8; 95% confidence interval, 1.7 to 4.7) and longer duration of hospitalization (parameter estimate: 7.3 days 95% confidence interval, 4.7 to 10.0), adjusting for neonatal and maternal factors along with medication exposures. Factors associated with a higher risk of AKI included: outborn delivery; resuscitation with epinephrine; admission diagnosis of hyperbilirubinemia, inborn errors of metabolism, or surgical need; frequent kidney function surveillance; and admission to a children's hospital. Those factors that were associated with a lower risk included multiple gestations, cesarean section, and exposures to antimicrobials, methylxanthines, diuretics, and vasopressors. Risk factors varied by gestational age strata. CONCLUSIONS AKI in the first postnatal week is common and associated with death and longer duration of hospitalization. The AWAKEN study demonstrates a number of specific risk factors that should serve as "red flags" for clinicians at the initiation of the neonatal intensive care unit course.
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Affiliation(s)
| | - Louis Boohaker
- University of Alabama at Birmingham, Birmingham, Alabama
| | - David Askenazi
- University of Alabama at Birmingham, Birmingham, Alabama
| | - Patrick D Brophy
- Golisano Children's Hospital, University of Rochester, Rochester, New York
| | - Carl D'Angio
- Golisano Children's Hospital, University of Rochester, Rochester, New York
| | - Mamta Fuloria
- Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York
| | - Jason Gien
- Children's Hospital Colorado, University of Colorado, Aurora, Colorado
| | | | - Sangeeta Hingorani
- Seattle Children's Hospital/University of Washington, Seattle, Washington
| | - Susan Ingraham
- Kapi'olani Medical Center for Women and Children, Honolulu, Hawaii
| | - Ayesa Mian
- Golisano Children's Hospital, University of Rochester, Rochester, New York
| | - Robin K Ohls
- University of New Mexico, Albuquerque, New Mexico
| | | | | | - Mary Revenis
- Children's National Medical Center, The George Washington University School of Medicine and The Health Sciences, Washington, DC
| | - Subrata Sarkar
- C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, Michigan; and
| | | | - Michelle Starr
- Seattle Children's Hospital/University of Washington, Seattle, Washington
| | - Alison L Kent
- Golisano Children's Hospital, University of Rochester, Rochester, New York
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Mrocki MM, Nguyen VB, Lombardo P, Sutherland MR, Bensley JG, Nitsos I, Allison BJ, Harding R, De Matteo R, Schneider M, Polglase GR, Black MJ. Moderate preterm birth affects right ventricular structure and function and pulmonary artery blood flow in adult sheep. J Physiol 2018; 596:5965-5975. [PMID: 29508407 DOI: 10.1113/jp275654] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 02/26/2018] [Indexed: 12/25/2022] Open
Abstract
KEY POINTS Preterm birth occurs when the heart muscle is immature and ill-prepared for the changes in heart and lung function at birth. MRI imaging studies show differences in the growth and function of the heart of young adults born preterm, with the effects more pronounced in the right ventricle. The findings of this study, conducted in sheep, showed that following moderate preterm birth the right ventricular wall was thinner in adulthood, with a reduction in the number and size of the heart muscle cells; in addition, there was impaired blood flow in the main artery leading from the right ventricle to the lungs. The findings indicate that being born only a few weeks early adversely affects the cellular structure of the right ventricle and blood flow to the lungs in adulthood. The reduced number of heart muscle cells has the potential to deleteriously affect right ventricular growth potential and function. ABSTRACT Preterm birth prematurely exposes the immature heart to the haemodynamic transition at birth, which has the potential to induce abnormal cardiac remodelling. Magnetic resonance imaging studies in young adults born preterm have shown abnormalities in the gross structure of the ventricles (particularly the right ventricle; RV), but the cellular basis of these alterations is unknown. The aim of this study, conducted in sheep, was to determine the effect of moderate preterm birth on RV cellular structure and function in early adulthood. Male singleton lambs were delivered moderately preterm (132 ± 1 days; n = 7) or at term (147 ± 1 days; n = 7). At 14.5 months of age, intra-arterial blood pressure and heart rate were measured. Pulmonary artery diameter and peak systolic blood flow were determined using ultrasound imaging, and RV stroke volume and output calculated. Cardiomyocyte number, size, nuclearity and levels of cardiac fibrosis were subsequently assessed in perfusion-fixed hearts using image analysis and stereological methods. Blood pressure (systolic, diastolic and mean), heart rate, levels of myocardial fibrosis and RV stroke volume and output were not different between groups. There was, however, a significant reduction in RV wall thickness in preterm sheep, and this was accompanied by a significant reduction in peak systolic blood flow in the pulmonary artery and in RV cardiomyocyte number. Cellular changes in the RV wall and reduced pulmonary artery blood flow following preterm birth have the potential to adversely affect cardiac and respiratory haemodynamics, especially when the cardiovascular system is physiologically or pathologically challenged.
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Affiliation(s)
- Marshall M Mrocki
- Biomedicine Discovery Institute and the Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Vivian B Nguyen
- Biomedicine Discovery Institute and the Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Paul Lombardo
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Victoria, Australia
| | - Megan R Sutherland
- Biomedicine Discovery Institute and the Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Jonathan G Bensley
- Biomedicine Discovery Institute and the Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Ilias Nitsos
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Clayton, Victoria, Australia
| | - Beth J Allison
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Clayton, Victoria, Australia
| | - Richard Harding
- Biomedicine Discovery Institute and the Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Robert De Matteo
- Biomedicine Discovery Institute and the Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Michal Schneider
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Victoria, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - M Jane Black
- Biomedicine Discovery Institute and the Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
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Stonestreet BS, Watkins S, Petersson KH, Sadowska GB. Effects of Multiple Courses of Antenatal Corticosteroids on Regional Brain and Somatic Tissue Water Content in Ovine Fetuses. ACTA ACUST UNITED AC 2016; 11:166-74. [PMID: 15051036 DOI: 10.1016/j.jsgi.2003.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To study the effects of single and multiple courses of antenatal corticosteroids on tissue water content in ovine fetuses. METHODS After chronic catheterization of the ewes and fetuses, the ewes were randomly assigned to receive single or multiple courses of dexamethasone or placebo beginning at 104-106 or 76-78 days' gestation, respectively. In the single course groups, the ewes received dexamethasone (6 mg, n = 6) or placebo (n = 6) as four intramuscular injections every 12 hours over 48 hours. The fetal tissues were harvested for water content determination 66 hours after the first injection of dexamethasone or placebo was given. In the multiple-course groups, the ewes received the same treatment (dexamethasone, n = 10, or placebo, n = 8), once a week for 5 weeks starting at 76-78 days' gestation. In these groups, the tissues were harvested 66 hours after the first the injection of the fifth and last treatment course. In both groups, tissues were harvested at 106-107 days' gestation. Tissue water content was determined by wet-to-dry weight ratio in brain (cerebral cortex, caudate nucleus, cerebellum, midbrain, and medulla) and somatic tissues (kidney, liver, muscle, and skin). RESULTS Water content in the brain regions (cerebellum and medulla) was lower (P <.05) in fetuses of dexamethasone-treated ewes than placebo-treated ewes after the multiple course but not the single course. Water content of somatic tissue was lower (P <.05) in fetuses of dexamethasone-treated ewes than placebo-treated ewes after the multiple courses, and in the liver after a single course. CONCLUSION Dexamethasone treatment of ewes at 70% of gestation results in decreased regional brain water content in the fetuses after multiple but not single treatment courses, in somatic tissues (kidney, liver, muscle, and skin) after multiple courses, and in the liver after a single course.
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Affiliation(s)
- Barbara S Stonestreet
- Department of Pediatrics, Brown University Medical School, Women and Infants' Hospital of Rhode Island, Providence 02905-2499, USA.
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8
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Peffer ME, Zhang JY, Umfrey L, Rudine AC, Monaghan AP, DeFranco DB. Minireview: the impact of antenatal therapeutic synthetic glucocorticoids on the developing fetal brain. Mol Endocrinol 2015; 29:658-66. [PMID: 25763611 DOI: 10.1210/me.2015-1042] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The life-threatening, emotional, and economic burdens of premature birth have been greatly alleviated by antenatal glucocorticoid (GC) treatment. Antenatal GCs accelerate tissue development reducing respiratory distress syndrome and intraventricular hemorrhage in premature infants. However, they can also alter developmental processes in the brain and trigger adverse behavioral and metabolic outcomes later in life. This review summarizes animal model and clinical studies that examined the impact of antenatal GCs on the developing brain. In addition, we describe studies that assess glucocorticoid receptor (GR) action in neural stem/progenitor cells (NSPCs) in vivo and in vitro. We highlight recent work from our group on two GR pathways that impact NSPC proliferation, ie, a nongenomic GR pathway that regulates gap junction intercellular communication between coupled NSPCs through site-specific phosphorylation of connexin 43 and a genomic pathway driven by differential promoter recruitment of a specific GR phosphoisoform.
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Affiliation(s)
- Melanie E Peffer
- Program in Integrative Molecular Biology (M.E.P., D.B.D.), Department of Pharmacology and Chemical Biology (M.E.P., J.Y.Z., L.U., D.B.D.), and Newborn Medicine Program (A.C.R.), Children's Hospital of Pittsburgh, and Department of Neurobiology (A.P.M.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260
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9
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Gubhaju L, Sutherland MR, Black MJ. Preterm birth and the kidney: implications for long-term renal health. Reprod Sci 2011; 18:322-33. [PMID: 21427457 DOI: 10.1177/1933719111401659] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although the majority of preterm neonates now survive infancy, there is emerging epidemiological evidence to demonstrate that individuals born preterm exhibit an elevated risk for the development of hypertension and renal impairment later in life, thus supporting the developmental origins of health and disease hypothesis. The increased risk may potentially be attributed to a negative impact of preterm birth on nephron endowment. Indeed, at the time when most preterm neonates are delivered, nephrogenesis in the kidney is still ongoing with the majority of nephrons normally formed during the third trimester of pregnancy. A number of clinical studies have provided evidence of altered renal function during the neonatal period, but to date there have been limited studies describing the consequences of preterm birth on kidney structure. Importantly, studies in the preterm baboon have shown that nephrogenesis is clearly ongoing following preterm birth; however, the presence of abnormal glomeruli (up to 18% in some cases) is of concern. Similar glomerular abnormalities have been described in autopsied preterm infants. Prenatal and postnatal factors such as exposure to certain medications, hyperoxia and intrauterine and/or extrauterine growth restriction are likely to have a significant influence on nephrogenesis and final nephron endowment. Further studies are required to determine the factors contributing to renal maldevelopment and to identify potential interventional strategies to maximize nephron endowment at the start of life, thereby optimizing long-term renal health for preterm individuals.
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Affiliation(s)
- Lina Gubhaju
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
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10
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Sutherland MR, Gubhaju L, Black MJ. Stereological assessment of renal development in a baboon model of preterm birth. Am J Nephrol 2011; 33 Suppl 1:25-33. [PMID: 21659732 DOI: 10.1159/000327073] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
At the time when most preterm babies are delivered, nephrogenesis is still ongoing, with the majority of nephrons normally formed during the third trimester of pregnancy. The extrauterine environment, however, is suboptimal for organogenesis, and therefore renal development is likely to be adversely affected by preterm birth. In the long-term, there is emerging evidence of high blood pressure and renal dysfunction amongst young adults born preterm. There is little knowledge to date, however, regarding the effects of preterm birth on renal structural development, perhaps due to the lack of an appropriate animal model. We have demonstrated that the baboon (Papio sp.) has a similar time course of nephrogenesis as the human kidney, and the baboon neonate can also be cared for in the same manner as a human neonate following preterm birth. Through a series of studies assessing renal development in the baboon model of preterm birth, involving the use of gold-standard stereological techniques, we have demonstrated that nephron endowment in the preterm baboon kidney is not reduced. Furthermore, antenatal glucocorticoid exposure prior to preterm delivery was associated with an increase in mature nephrons. There was, however, evidence of morphological abnormalities in a variable percentage of the glomeruli formed ex utero. Further research is therefore essential in order to establish what factors are involved in contributing to the glomerular abnormalities, and to identify ways in which 'normal' renal development can be conserved and optimised in the extrauterine setting.
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Affiliation(s)
- Megan R Sutherland
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Vic., Australia
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Kim CR, Sadowska GB, Newton SA, Merino M, Petersson KH, Padbury JF, Stonestreet BS. Na+,K+-ATPase activity and subunit protein expression: ontogeny and effects of exogenous and endogenous steroids on the cerebral cortex and renal cortex of sheep. Reprod Sci 2010; 18:359-73. [PMID: 20959645 DOI: 10.1177/1933719110385137] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We examined the effects of development, exogenous, and endogenous glucocorticoids on Na(+),K(+)-ATPase activity and subunit protein expression in ovine cerebral cortices and renal cortices. Ewes at 60%, 80%, and 90% gestation, newborns, and adults received 4 dexamethasone or placebo injections. Cerebral cortex Na(+),K(+)-ATPase activity was higher (P < .05) in placebo-treated newborns than fetuses of placebo-treated ewes and adults, α(1)-expression was higher at 90% gestation than the other ages; α(2)-expression was higher in newborns than fetuses; α(3)-expression was higher in newborns than 60% gestation; β(1)-expression was higher in newborns than the other ages, and β(2)-expression higher at 60% than 80% and 90% gestation, and in adults. Renal cortex Na(+),K(+)-ATPase activity was higher in placebo-treated adults and newborns than fetuses. Cerebral cortex Na(+),K(+)-ATPase activity was higher in dexamethasone- than placebo-treated adults, and α(1)-expression higher in fetuses of dexamethasone- than placebo-treated ewes at 60% and 80% gestation. Renal cortex Na(+),K(+)-ATPase activity and α(1)-expression were higher in fetuses of dexamethasone- than placebo-treated ewes at each gestational age, and β(1)-expression was higher in fetuses of dexamethasone- than placebo-treated ewes at 90% gestation and in dexamethasone- than placebo-treated adults. Cerebral cortex Na(+),K(+)-ATPase activity, α(1)-expression, β(1)-expression, and renal cortex α(1)-expression correlated directly with increases in fetal cortisol. In conclusion, Na(+),K(+)-ATPase activity and subunit expression exhibit specific developmental patterns in brain and kidney; exogenous glucocorticoids regulate activity and subunit expression in brain and kidney at some ages; endogenous increases in fetal cortisol regulate cerebral Na(+),K(+)-ATPase, but exogenous glucocorticoids have a greater effect on renal than cerebral Na(+),K(+)-ATPase.
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Affiliation(s)
- Chang-Ryul Kim
- Department of Pediatrics, Women and Infants Hospital of Rhode Island, The Warren Alpert Medical School of Brown University, Providence, RI 02905,USA
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Duncan AR, Sadowska GB, Stonestreet BS. Ontogeny and the effects of exogenous and endogenous glucocorticoids on tight junction protein expression in ovine cerebral cortices. Brain Res 2009; 1303:15-25. [PMID: 19785997 DOI: 10.1016/j.brainres.2009.09.086] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2009] [Revised: 09/12/2009] [Accepted: 09/21/2009] [Indexed: 10/20/2022]
Abstract
Maternal glucocorticoid treatment reduces blood-brain permeability early, but not late in fetal development, and pretreatment with glucocorticoids does not affect barrier permeability in newborn lambs. In addition, endogenous increases in plasma cortisol levels are associated with decreases in blood-brain barrier permeability during normal fetal development. Therefore, we tested the hypotheses that development as well as endogenous and exogenous glucocorticoids alters the expression of tight junction proteins in the cerebral cortex of sheep. Cerebral cortices from fetuses at 60%, 70%, and 90% of gestation, newborn and adult sheep were snap frozen after four 6-mg dexamethasone or placebo injections were given over 48-h to the ewes and adult sheep. Lambs were treated similarly with 0.25 mg/kg-dexamethasone or placebo. Tight junction protein expression was measured by Western immunoblot. Claudin-1 was higher (P<0.05) in fetuses at 60% of gestation than in newborn and adult sheep. Claudin-5 was higher at 60% than 70% of gestation, and than in newborn and adult sheep. ZO-1 was higher in newborn than adult sheep. ZO-2 was higher at 90% gestation, in newborn and adult sheep than 60% gestation. Claudin-5 was higher in dexamethasone than placebo-treated lambs, and ZO-2 was higher in fetuses of dexamethasone than placebo-treated ewes at 90% gestation. ZO-2 expression demonstrated a direct correlation with increases in plasma cortisol during fetal development. We conclude that claudin-1, claudin-5, ZO-1, and ZO-2 expression exhibit differential developmental regulation, exogenous glucocorticoids regulate claudin-5 and ZO-2 in vivo at some, but not all ages, and increases in endogenous fetal glucocorticoids are associated with increases in ZO-2 expression, but not with occludin, claudin-1, claudin-5 or ZO-1 expression in ovine cerebral cortices.
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Affiliation(s)
- Anna R Duncan
- The Warren Alpert Medical School of Brown University Department of Pediatrics Women and Infants' Hospital of Rhode Island 101 Dudley Street Providence, RI 02905-2499, USA
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13
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Gubhaju L, Sutherland MR, Yoder BA, Zulli A, Bertram JF, Black MJ. Is nephrogenesis affected by preterm birth? Studies in a non-human primate model. Am J Physiol Renal Physiol 2009; 297:F1668-77. [PMID: 19759270 DOI: 10.1152/ajprenal.00163.2009] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Nephrogenesis occurs predominantly in late gestation at a time when preterm infants are already delivered. The aims of this study were to assess the effect of preterm birth and the effect of antenatal glucocorticoid treatment on nephrogenesis. Preterm baboons, which were delivered at 125 days gestation and ventilated for up to 21 days postnatally, were compared with gestational controls. A cohort of preterm baboons that had been exposed to antenatal glucocorticoids were compared with unexposed preterm baboons. The number of glomerular generations was estimated using a medullary ray glomerular-counting method, and glomerular number was estimated using unbiased stereology. CD31 and WT-1 localization was examined using immunohistochemistry and VEGF was localized using in situ hybridization. The number of glomerular generations was not affected by preterm birth, and total glomerular numbers were within the normal range. Kidneys were significantly enlarged in preterm baboons with a significant decrease in glomerular density (number of glomeruli per gram of kidney) in the preterm kidney compared with gestational controls. Neonates exposed to antenatal steroids had an increased kidney-to-body weight ratio and also more developed glomeruli compared with unexposed controls. Abnormal glomeruli, with a cystic Bowman's space and shrunken glomerular tuft, were often present in the superficial renal cortex of both the steroid-exposed and unexposed preterm kidneys; steroid exposure had no significant effect on the proportion of abnormal glomeruli. The proportion of abnormal glomeruli in the preterm kidneys ranged from 0.2 to 18%. In conclusion, although nephrogenesis is ongoing in the extrauterine environment, our findings demonstrate that preterm birth, independent of steroid exposure, is associated with a high proportion of abnormal glomeruli in some, but not all neonatal kidneys. Whether final nephron endowment is affected in those kidneys exhibiting a high proportion of abnormal glomeruli is yet to be confirmed.
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Affiliation(s)
- Lina Gubhaju
- Dept. of Anatomy and Developmental Biology, Monash Univ., Victoria 3800, Australia
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Mehter NS, Sadowska GB, Malaeb SN, Stonestreet BS. Na+, K+-ATPase activity and subunit isoform protein abundance: effects of antenatal glucocorticoids in the frontal cerebral cortex and renal cortex of ovine fetuses. Reprod Sci 2008; 16:294-307. [PMID: 19001554 DOI: 10.1177/1933719108325507] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We examined the effects of single and multiple maternal glucocorticoid courses on cerebral cortical (CC) and renal cortical (RC) Na(+),K(+)-ATPase activity and protein isoform abundance in fetal sheep. Ewes received four dexamethasone or placebo injections in the single course (SC) groups, and the same treatment once a week for five-weeks in the multiple course (MC) groups. CC Na(+),K(+)-ATPase a(2)-abundance was higher (P<0.05) and beta(2)-abundance lower in the SC dexamethasone than placebo group, but Na(+),K(+)-ATPase activity did not change. CC Na(+),K(+)-ATPase activity, a(1)-, beta(1) -, and beta(2)-abundance were lower in the MC dexamethasone than placebo group, but a(2)- and a(3)-abundance did not change. Both dexamethasone courses did not affect CC cell number. RC Na(+),K(+)-ATPase activity, a(1)- and beta(1) -abundance were higher in the MC dexamethasone than placebo group, but did not change in the SC dexamethasone group. We conclude MC, but not a SC of dexamethasone, affect fetal cerebral and renal Na(+),K(+)-ATPase, and MC result in differential effects on Na(+),K(+)-ATPase in these organs.
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Affiliation(s)
- Najma S Mehter
- Warren Alpert Medical School of Brown University, Department of Pediatrics, Women & Infants' Hospital of Rhode Island, Providence, Rhode Island 02905, USA
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Boubred F, Vendemmia M, Garcia-Meric P, Buffat C, Millet V, Simeoni U. Effects of maternally administered drugs on the fetal and neonatal kidney. Drug Saf 2006; 29:397-419. [PMID: 16689556 DOI: 10.2165/00002018-200629050-00004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The number of pregnant women and women of childbearing age who are receiving drugs is increasing. A variety of drugs are prescribed for either complications of pregnancy or maternal diseases that existed prior to the pregnancy. Such drugs cross the placental barrier, enter the fetal circulation and potentially alter fetal development, particularly the development of the kidneys. Increased incidences of intrauterine growth retardation and adverse renal effects have been reported. The fetus and the newborn infant may thus experience renal failure, varying from transient oligohydramnios to severe neonatal renal insufficiency leading to death. Such adverse effects may particularly occur when fetuses are exposed to NSAIDs, ACE inhibitors and specific angiotensin II receptor type 1 antagonists. In addition to functional adverse effects, in utero exposure to drugs may affect renal structure itself and produce renal congenital abnormalities, including cystic dysplasia, tubular dysgenesis, ischaemic damage and a reduced nephron number. Experimental studies raise the question of potential long-term adverse effects, including renal dysfunction and arterial hypertension in adulthood. Although neonatal data for many drugs are reassuring, such findings stress the importance of long-term follow-up of infants exposed in utero to certain drugs that have been administered to the mother.
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Affiliation(s)
- Farid Boubred
- Faculté de Médecine, Université de la Méditerrannée and Assistance Publique Hôpitaux de Marseille, Hôpital de la Conception, Service de Néonatologie, Marseille, France
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16
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Sadowska GB, Patlak CS, Petersson KH, Stonestreet BS. Effects of multiple courses of antenatal corticosteroids on blood-brain barrier permeability in the ovine fetus. ACTA ACUST UNITED AC 2006; 13:248-55. [PMID: 16697940 DOI: 10.1016/j.jsgi.2006.02.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2005] [Indexed: 10/24/2022]
Abstract
OBJECTIVE To test the hypothesis that multiple courses of antenatal corticosteroids accentuate the decreases in blood-brain barrier permeability observed after a single course of corticosteroids in preterm ovine fetuses. METHODS Chronically instrumented 106-day gestation ovine fetuses were studied after single and multiple courses of dexamethasone or placebo were given to ewes beginning at 104 to 106 or 76 to 78 days of gestation, respectively. In the single-course groups, the ewes received dexamethasone (6 mg, n = 6) or placebo (n = 6) as four intramuscular injections every 12 hours over 48 hours. In the multiple course groups, the ewes received the same treatment (dexamethasone, n = 9, or placebo, n = 8), once per week for 5 weeks starting at 76 to 78 days of gestation. Blood-brain barrier permeability was quantified with the blood-to-brain transfer constant (K(i)) for alpha-aminoisobutyric acid (AIB) in the brain regions of the fetuses 12 hours after the last injection of dexamethasone was given to the ewes at 106 to 107 days of gestation. RESULTS Both single (analysis of variance [ANOVA]; main effects for dexamethasone treatment, F = 5.92, P <.04) and multiple (ANOVA; main effects for dexamethasone treatment, F = 4.74, P <.04) courses of antenatal corticosteroids were associated with decreases in blood-brain barrier permeability in the brain regions of the ovine fetus. However, the multiple courses did not accentuate (ANOVA; main effects for single versus multiple courses, F = 1.06, P = .32) the decreases in permeability observed after a single course. CONCLUSION Contrary to our hypothesis, antenatal treatment with a 5-week course of corticosteroids did not accentuate the reductions in blood-brain barrier permeability that we observed after a single course of corticosteroids in the fetus.
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Affiliation(s)
- Grazyna B Sadowska
- Department of Pediatrics, Brown University Medical School, Women and Infants' Hospital of Rhode Island, Providence, RI 02905-2499 , USA
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17
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Kim CR, Sadowska GB, Petersson KH, Merino M, Sysyn GD, Padbury JF, Stonestreet BS. Effects of postnatal steroids on Na+/K+-ATPase activity and alpha1- and beta1-subunit protein expression in the cerebral cortex and renal cortex of newborn lambs. Reprod Fertil Dev 2006; 18:413-23. [PMID: 16737634 DOI: 10.1071/rd05114] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2005] [Accepted: 01/02/2006] [Indexed: 11/23/2022] Open
Abstract
Na(+)/K(+)-ATPase is a membrane-bound enzyme responsible for Na(+)/K(+) translocation across cell membranes. It is essential for the generation of electrochemical gradients, which control the ionic environment necessary for electrical activity and water and electrolyte balance. Newborn infants who are at risk of developing bronchopulmonary dysplasia (BPD) are frequently treated with corticosteroids. Although these infants are at risk for neurological, water and electrolyte abnormalities, there is little information regarding the effects of clinically relevant doses of corticosteroids on Na(+)/K(+)-ATPase activity and protein isoform expression in the brain and kidney of newborns. In the present study, we examined the effects of dexamethasone on cerebral cortical and renal cortical Na(+)/K(+)-ATPase activity and alpha1- and beta1-protein isoform expression in newborn lambs. Lambs were given four injections of a placebo (n = 11) or one of three different doses of dexamethasone (0.01 mg kg(-1), n = 9; 0.25 mg kg(-1), n = 11; or 0.50 mg kg(-1), n = 9) 12 h apart on Postnatal Days 3 and 4 up to 18 h before harvest of the cerebral cortex and renal cortex. We selected doses in a range to approximate those used to treat infants with BPD. Na(+)/K(+)-ATPase activity was measured in membrane preparations as ouabain-sensitive inorganic phosphate liberation from ATP and alpha1- and beta1-subunit abundance by Western immunoblot. Postnatal treatment of lambs with dexamethasone resulted in a 21.4% increase in Na(+)/K(+)-ATPase activity and a 30.4% increase in catalytic alpha1-protein expression in the cerebral cortex at a dose of 0.50 mg kg(-1) dexamethasone, but not at the lower doses. Dexamethasone treatment was not associated with changes in beta1-isoform expression in the cerebral cortex. In the kidney, dexamethasone treatment was not associated with significant changes in Na(+)/K(+)-ATPase activity or alpha1- or beta1-isoform expression for the doses we examined. Therefore, clinically relevant corticosteroid treatment exerts dose-related, differential organ-specific effects on Na(+)/K(+)-ATPase activity and protein isoform expression in newborn lambs.
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Affiliation(s)
- Chang-Ryul Kim
- Pediatrics, Women & Infants' Hospital of Rhode Island and Brown Medical School, Providence, RI 02905-2499, USA
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18
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Williams SJ, Olson DM, Zaragoza DB, Coulter CL, Butler TG, Ross JT, McMillen IC. Cortisol infusion decreases renin, but not PGHS-2, EP2, or EP4 mRNA expression in the kidney of the fetal sheep at days 109-116. Pediatr Res 2004; 55:637-44. [PMID: 14711886 DOI: 10.1203/01.pdr.0000113786.35966.2c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Renal prostaglandins (PG), renin, and cortisol are necessary for normal kidney development and function during fetal life. We examined the effects of cortisol infusion before completion of nephrogenesis (d 109-116 gestation; 2.0-3.0 mg hydrocortisone succinate/24 h) on the renal mRNA expression of PGHS-2, the PGE(2) receptors, EP(2) and EP(4), and renin in fetal sheep. Cortisol infusion raised plasma cortisol levels to 42.8 +/- 6.0 nmol/L compared with saline infusion levels of 1.5 +/- 0.5 nmol/L (p < 0.001), but had no effect on fetal body weight, proportional kidney mass, or blood gases. Cortisol decreased significantly the relative expression of renin mRNA (saline: 0.93 +/- 0.06 units; cortisol: 0.32 +/- 0.03 units, p < 0.05), however it had no effect upon the expression of PGHS-2, EP(2), or EP(4) mRNA in fetal sheep kidney. Although there is substantial evidence that PGE(2) acting through either the EP(2) or EP(4) receptor stimulates renin synthesis in the adult kidney, our results have demonstrated that before the completion of nephrogenesis, cortisol down-regulation of renin mRNA expression is independent of any change in the expression of PGHS-2, EP(2), or EP(4) mRNA expression. During nephrogenesis, the insensitivity of PGHS-2, EP(2), and EP(4) expression to down-regulation by cortisol may permit continued PG regulation of renal development and urine formation.
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19
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Jahnukainen T, Chen M, Berg U, Celsi G. Antenatal glucocorticoids and renal function after birth. SEMINARS IN NEONATOLOGY : SN 2001; 6:351-5. [PMID: 11972436 DOI: 10.1053/siny.2001.0070] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Antenatal glucocorticoid treatment is widely used in cases of threatening preterm delivery. Both human and animal studies have confirmed that glucocorticoids promote pulmonary maturation in fetuses. Several studies indicate that prenatal glucocorticoids also stimulate renal maturation. Although the current knowledge about the effects of glucocorticoids on kidney function is mainly concentrated on short-term effects, there are animal studies suggesting that antenatal glucocorticoid treatment may also cause permanent changes in kidney morphology and renal function. It still remains to be investigated if antenatal glucocorticoid treatment induces long-term effects in humans.
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Affiliation(s)
- T Jahnukainen
- Hospital for Children and Adolescents, Helsinki University, Helsinki, Finland
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20
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Abstract
The objective of the present study was to examine the effect of antenatal or postnatal treatment with corticosteroids on the NMDA receptor, one of the mediators of both normal brain development and hypoxic-ischemic injury, by determining the characteristics of the receptor MK-801 binding site in untreated and corticosteroid-treated fetal and newborn lambs. (3)H-MK-801 binding was performed in cerebral cortical cell membranes from fetal sheep at 88, 120, and 136 d gestation (term = 150 d), and from 5-d-old lambs and adult ewes. Animals were randomized to receive dexamethasone [fetuses: 6 mg, i.m. every 12 hr for four doses to mother; lambs: 0.01 mg/kg (low dose) or 0.25 mg/kg (high dose) every 12 hr for four doses] or placebo. During development, B(max) (apparent number of receptors) increased, reaching a maximum in 5-d-old lambs (p < 0.05) and decreasing in the adult brain. K(d) (dissociation constant) did not change, suggesting that receptor affinity was not altered during maturation. Dexamethasone treatment had no effect on MK-801 binding in the fetus or adult, but in lambs was associated with a significant decrease in B(max) from 2.17 +/- 0.18 pmol/mg protein in placebo-treated animals to 1.65 +/- 0.8 and 1.62 +/- 0.07 pmol/mg protein in low-dose and high-dose animals, respectively. Affinity for (3)H-MK-801 decreased 20% after dexamethasone treatment in lambs only (p < 0.05). Thus, dexamethasone treatment appears to modify the NMDA receptor only during a specific period of brain development.
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Sysyn GD, Petersson KH, Patlak CS, Sadowska GB, Stonestreet BS. Effects of postnatal dexamethasone on blood-brain barrier permeability and brain water content in newborn lambs. Am J Physiol Regul Integr Comp Physiol 2001; 280:R547-53. [PMID: 11208586 DOI: 10.1152/ajpregu.2001.280.2.r547] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We showed that antenatal corticosteroids reduced blood-brain barrier permeability in fetuses at 60 and 80%, but not 90% of gestation, and decreased brain water content in fetuses. Our objective was to examine the effects of postnatal corticosteroids on regional blood-brain barrier permeability and brain water content in newborn lambs. Three dexamethasone treatment groups were studied in 3- to 5-day-old lambs. A 0.01 mg/kg dose was selected to estimate the amount of dexamethasone that might have reached fetuses via antenatal treatment of ewes in our previous studies. The other doses (0.25 and 0.5 mg/kg) were chosen to approximate those used clinically to treat infants with bronchopulmonary dysplasia. Lambs were randomly assigned to receive four intramuscular injections of dexamethasone or placebo given 12 h apart on days 3 and 4 of age. Blood-brain barrier function was measured with the blood-to-brain transfer constant (K(i)) to alpha-aminoisobutyric acid, brain plasma volume was measured with polyethylene glycol for the calculation of K(i,) and brain water was measured by wet-to-dry tissue weights. Postnatal treatment with corticosteroids did not reduce barrier permeability in newborn lambs. Brain blood volume was higher in the 0.25 and 0.5 mg/kg dose dexamethasone groups than in the placebo group. Brain water content did not differ among the groups. We conclude that postnatal treatment with corticosteroids did not reduce regional blood-brain barrier permeability or brain water content but increased the brain plasma volume in newborn lambs. These findings are consistent with our previous work indicating that barrier permeability is responsive to corticosteroids at 60 and 80% of gestation and brain water regulation at 60% of gestation, but not in near-term fetuses or newborn lambs.
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Affiliation(s)
- G D Sysyn
- Department of Pediatrics, Women and Infants' Hospital of Rhode Island, Brown University School of Medicine, Providence, Rhode Island 02905, USA
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22
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Stonestreet BS, Sadowska GB, McKnight AJ, Patlak C, Petersson KH. Exogenous and endogenous corticosteroids modulate blood-brain barrier development in the ovine fetus. Am J Physiol Regul Integr Comp Physiol 2000; 279:R468-77. [PMID: 10938234 DOI: 10.1152/ajpregu.2000.279.2.r468] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously reported decreases in blood-brain barrier permeability in the ovine fetus at 80% of gestation after antenatal corticosteroids and shown that permeability is not reduced in newborn lambs after postnatal corticosteroids. We now test the hypotheses that exogenous antenatal corticosteroids decrease blood-brain barrier permeability at 60% but not 90% of gestation in ovine fetuses and that endogenous increases in plasma cortisol concentrations are associated with ontogenic decreases in barrier permeability during gestation. Chronically instrumented ovine fetuses were studied 12 h after the last of four 6-mg dexamethasone or placebo injections were given 12 h apart over 48 h to ewes. Fetuses at 80% of gestation from placebo-treated ewes studied under the same protocol were also included. Blood-brain barrier function was quantified with the blood-to-brain transfer constant (K(i)) to alpha-aminoisobutyric acid. K(i) values were lower in cerebral cortex, caudate nucleus, hippocampus, superior colliculus, thalamus, medulla, and cervical spinal cord in fetuses of dexamethasone- than placebo-treated ewes at 60% but not 90% of gestation. Regional brain K(i) values demonstrated inverse correlations with increases in gestation and plasma cortisol concentrations in most brain regions. We conclude that maternal treatment with exogenous corticosteroids was associated with decreases in blood-brain barrier permeability at 60% but not 90% of gestation and that increases in gestation and endogenous cortisol concentrations were associated with ontogenic decreases in barrier permeability during fetal development.
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Affiliation(s)
- B S Stonestreet
- Department of Pediatrics, Women and Infants Hospital of Rhode Island, Brown University School of Medicine, Providence 02905, USA.
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23
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Fetal renal circulation. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s1569-2590(00)09070-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Petershack JA, Nagaraja SC, Guillery EN. Role of glucocorticoids in the maturation of renal cortical Na+-K+-ATPase during fetal life in sheep. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:R1825-32. [PMID: 10362766 DOI: 10.1152/ajpregu.1999.276.6.r1825] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Glucocorticoid levels increase greatly at the time of birth in humans and sheep, coinciding with an increased ability of the kidney to reabsorb sodium. Cortisol induces proximal tubule apical membrane Na+/H+ exchanger maturation in near-term fetal sheep. Proximal tubule salt transport is ultimately dependent on Na+ pump activity, so we studied the effects of cortisol treatment on renal cortical Na+-K+-ATPase. We first looked at six 140 day gestation fetal sheep (term is 145) and compared their renal cortical Na+-K+-ATPase to that of six 1-day-old lambs. Na+-K+-ATPase activity increased 80% after birth. Then nine pairs of twin fetal sheep were chronically instrumented at 127 days gestation. After 72 h recovery, one twin was given a 48-h continuous intraperitoneal infusion of cortisol. Both twins were then killed, and their renal cortices were studied. Na+-K+-ATPase activity increased 122% with cortisol treatment; activity equaled that of 1-day-old lambs. Protein abundance of the alpha1-subunit of the Na+-K+-ATPase increased 19%; the beta1-subunit increased 39% with cortisol treatment. mRNA abundance of the alpha1-subunit increased 58%; the beta1-subunit increased 72%. These results indicate that cortisol matures Na+-K+-ATPase activity.
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Affiliation(s)
- J A Petershack
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan 48197, USA.
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Stonestreet BS, Petersson KH, Sadowska GB, Pettigrew KD, Patlak CS. Antenatal steroids decrease blood-brain barrier permeability in the ovine fetus. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:R283-9. [PMID: 9950903 DOI: 10.1152/ajpregu.1999.276.2.r283] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Antenatal corticosteroid therapy reduces the incidence of intraventricular hemorrhage in premature infants. Enhanced microvascular integrity might provide protection against intraventricular hemorrhage. In the adult, there is evidence to suggest that the blood-brain barrier may be under hormonal control. We hypothesized that antenatal corticosteroids decrease blood-brain barrier permeability in the preterm ovine fetus. Chronically instrumented 120-day-gestation fetuses were studied 12 h after the last of four 6-mg dexamethasone (n = 5) or placebo (n = 6) injections had been given over 48 h to the ewes. Blood-brain barrier function was quantified with the blood-to-brain transfer constant (Ki) for alpha-aminoisobutyric acid (AIB). Ki was significantly lower across brain regions in the fetuses of ewes that received antenatal dexamethasone compared with placebo (ANOVA; interaction, F = 2.54, P < 0.004). In fetuses of dexamethasone- and placebo-treated ewes, Ki (microliter . g brain wt-1. min-1, mean +/- SD) was, respectively, 2.43 +/- 0.27 vs. 3.41 +/- 0.74 in the cortex, 4.46 +/- 0.49 vs. 5.29 +/- 0.85 in the cerebellum, and 3.70 +/- 0.49 vs. 5.11 +/- 0.70 in the medulla. We conclude that antenatal treatment with corticosteroids reduces blood-brain permeability in the ovine fetus.
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Affiliation(s)
- B S Stonestreet
- Department of Pediatrics, Women and Infants Hospital of Rhode Island, Brown University School of Medicine, Providence, Rhode Island 02905, USA
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26
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Ervin MG, Seidner SR, Leland MM, Ikegami M, Jobe AH. Direct fetal glucocorticoid treatment alters postnatal adaptation in premature newborn baboons. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:R1169-76. [PMID: 9575985 DOI: 10.1152/ajpregu.1998.274.4.r1169] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Abnormalities of premature newborn adaptation after preterm birth result in significant perinatal mortality and morbidity. We assessed the effects of short-term (24 h) fetal betamethasone exposure on preterm newborn baboon pulmonary and cardiovascular regulation and renal sodium handling during the first 24 h after birth. Male fetal baboons (Papio) (124-day gestation, term 185 days) received ultrasound-guided intramuscular injections of saline (n = 5) or betamethasone (0.5 mg/kg; n = 5). Fetuses were cesarean delivered 24 h later, treated with 100 mg/kg surfactant, and ventilated by adjusting peak inspiratory pressures to maintain PCO2 values of 35-50 mmHg for 24 h. Betamethasone- vs. saline-treated mean +/- SE newborn body weights (0.45 +/- 0.02 vs. 0.41 +/- 0.01 kg) were similar. Although prenatal betamethasone did not affect postnatal lung function (PCO2, arterial/alveolar O2 gradient, or dynamic compliance), plasma hormone (cortisol or thyroxine), or catecholamine levels, mean arterial pressure (25 +/- 1 vs. 32 +/- 1 mmHg), plasma sodium concentration (132 +/- 2 vs. 138 +/- 1 meq/l), glomerular filtration rate (0.07 +/- 0.02 vs. 0.16 +/- 0.02 ml.min-1.kg-1), and renal total sodium reabsorption (1.5 +/- 0.5 vs. 16.0 +/- 3.0 mu eq.min-1.kg-1) values were significantly lower in saline-treated than in betamethasone-treated newborns at 24 h. We conclude that despite the fact that there are no pulmonary and endocrine effects, antenatal glucocorticoid exposure alters premature newborn baboon vascular and renal glomerular function and improves sodium reabsorption after preterm delivery.
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Affiliation(s)
- M G Ervin
- Department of Obstetrics and Gynecology, University of California, Los Angeles School of Medicine, Harbor-UCLA Medical Center, Torrance 90502, USA
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Fowden AL, Li J, Forhead AJ. Glucocorticoids and the preparation for life after birth: are there long-term consequences of the life insurance? Proc Nutr Soc 1998; 57:113-22. [PMID: 9571716 DOI: 10.1079/pns19980017] [Citation(s) in RCA: 330] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- A L Fowden
- Department of Physiology, University of Cambridge, UK.
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Zhao XF, Scrocchi LA, Hammond GL. Glucocorticoids induce corticosteroid-binding globulin biosynthesis by immature mouse liver and kidney. J Steroid Biochem Mol Biol 1997; 60:163-9. [PMID: 9191973 DOI: 10.1016/s0960-0760(96)00181-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Marked changes in mouse corticosteroid-binding globulin (CBG) gene expression in the liver and kidney occur postnatally. To study the influence of glucocorticoids on the initiation of mouse CBG biosynthesis in these tissues during the first two weeks after birth, we administered dexamethasone (0.5 microgram/g body wt/day) to 4- and 11-day-old pups for three days. This resulted in higher serum CBG and hepatic CBG mRNA levels in animals, irrespective of their ages. Higher relative amounts of CBG mRNA in the kidneys of 14-day-old pups after three days of dexamethasone treatment co-incided with higher amounts of intact and proteolytically cleaved CGB in their urine, and both are indicative of increased CGB production by the developing renal tubules. When an additional group of 11-day-old pups (n = 4) was treated with 0.25 microgram dexamethasone/g body weight per day for five days, this also resulted in significantly higher levels of serum CBG (P < 0.01), hepatic CBG mRNA (P < 0.01) and renal CBG mRNA (P < 0.05), compared to littermates treated with the oil vehicle alone. In contrast, serum CBG levels progressively decreased in adult female mice during five days of treatment with 0.5 microgram dexamethasone/g body weight per day. Taken together, these data indicate that glucocorticoids induce murine CBG gene expression in the immature liver and kidney, and support the concept that the effects of glucocorticoids on CBG gene expression are developmentally stage-specific.
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Affiliation(s)
- X F Zhao
- Department of Obstetrics and Gynecology, University of Western Ontario, London, Canada
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Abstract
There is an increase in the survival rate of preterm infants due to rapid advances in medical knowledge and technology. However, the research and attention paid to the proper use of pharmacotherapy in these infants is still a relatively underdeveloped field. Effective and safe drug therapy requires a thorough understanding of human developmental biology and of the dynamic ontogeny of drug absorption, drug disposition, drug metabolism, and drug excretion. It is apparent that maturation of organ system function and changes in body composition during gestation and during the neonatal period exert a significant effect on the disposition of drugs. This review focuses on the effects of maturational and drug-induced changes in renal function on clinical pharmacokinetics in the preterm infant.
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Affiliation(s)
- J N van den Anker
- Department of Pediatrics, Erasmus University, Rotterdam, The Netherlands
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Ervin MG, Berry LM, Ikegami M, Jobe AH, Padbury JF, Polk DH. Single dose fetal betamethasone administration stabilizes postnatal glomerular filtration rate and alters endocrine function in premature lambs. Pediatr Res 1996; 40:645-51. [PMID: 8910927 DOI: 10.1203/00006450-199611000-00001] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
UNLABELLED These studies determined the effects of fetal treatment with betamethasone alone, or in combination with thyroid hormone (thyroxine; T4), on postnatal renal and endocrine adaptations in preterm newborn lambs. Ovine fetuses (126 d of gestation; term = 150 d) received single, ultrasound-guided intramuscular injections of saline, 0.5 mg/kg betamethasone (Celestone Soluspan, or 0.5 mg/kg betamethasone plus 60 micrograms/kg T4. After 48 h, lambs were delivered, treated with surfactant (Survanta, 100 mg/kg), and ventilated for 3 h. Due to maintained urine flow in the betamethasone-treated animals and a significant decrease in the saline group, betamethasone versus saline urine flow values (0.11 +/- 0.03 versus 0.03 +/- 0.004 mL.min-1.kg-1) were significantly elevated by the end of studies. GFR (1.5 +/- 0.3 versus 0.8 +/- 0.2 mL.min-1.kg-1) and mean blood pressure (61 +/- 4 versus 42 +/- 3 mm Hg) values also were higher in the betamethasone-treated animals. Although renal blood flow, renal plasma flow, and fractional sodium excretion rates did not differ, betamethasone versus saline values for the filtration fraction (11.9 +/- 1.5 versus 7.4 +/- 1.5%) and total sodium reabsorption (196 +/- 38 versus 81 +/- 16 microEq.min-1.kg-1) were increased. Betamethasone versus saline treatment also was associated with significant reductions in plasma angiotensin II (125 +/- 23 versus 550 +/- 140 pg/mL) and AVP (116 +/- 19 versus 230 +/- 77 pg/mL) levels. Overall, the effects of combined betamethasone + T4 treatment were similar to the effects of betamethasone alone. CONCLUSIONS 1) fetal betamethasone injection 48 h before delivery stabilizes GFR and significantly alters endocrine function in preterm newborn lambs, and 2) the addition of T4 does not augment betamethasone-induced renal and endocrine responses.
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Affiliation(s)
- M G Ervin
- Department of Obstetrics and Gynecology, University of California, Los Angeles School of Medicine, Harbor-UCLA Medical Center, Torrance 90502, USA
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Affiliation(s)
- J F Padbury
- Department of Pediatrics, University of California, Los Angeles, USA
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Dodic M, Wintour EM. Effects of prolonged (48 h) infusion of cortisol on blood pressure, renal function and fetal fluids in the immature ovine foetus. Clin Exp Pharmacol Physiol 1994; 21:971-80. [PMID: 7736656 DOI: 10.1111/j.1440-1681.1994.tb02659.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
1. This study describes the effects of prolonged (48 h) infusion of cortisol into ovine foetuses (100-110 days of gestation: term is 150 days) at a time when endogenous plasma cortisol concentrations are < 5 nmol/L. 2. In four chronically cannulated foetuses (107 +/- 0.9 day) the infusion of saline (0.9% NaCl; w:v 0.19 mL/h, 48 h) had no effect on blood pressure, renal function, or composition of amniotic and allantoic fluids. 3. In six foetuses (107 +/- 1 day) the infusion of cortisol (250 micrograms/h) increased plasma cortisol concentrations from 4.1 +/- 0.7 to 118 +/- 9 nmol/L (P < 0.001), increased mean arterial pressure from 34 +/- 1 to 40 +/- 1 mmHg (P < 0.001), increased glomerular filtration rate (P < 0.05), urine flow rate, and free water clearance (P < 0.01). 4. There was a significant increase in excretion rates of potassium and creatinine as a result of cortisol infusion, but no natriuresis, indicating some functional maturation of the fetal kidney. 5. Cortisol infusion had no effect on the volumes of amniotic and allantoic fluids; allantoic fluid composition was unchanged; significant decreases occurred in amniotic fluid osmolality, sodium and chloride concentrations, and in lung liquid osmolality, potassium, creatinine, magnesium, glucose and fructose concentrations. 6. Thus prolonged exposure of the immature ovine foetus to elevated cortisol concentrations produced significant alterations in the water and electrolyte balance of the foetus.
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Affiliation(s)
- M Dodic
- Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Victoria, Australia
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Robillard JE, Smith FG, Segar JL, Guillery EN, Jose PA. Mechanisms regulating renal sodium excretion during development. Pediatr Nephrol 1992; 6:205-13. [PMID: 1533309 DOI: 10.1007/bf00866320] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The present review focuses on the ontogeny of mechanisms involved in renal sodium excretion during renal maturation. The effect of birth on renal excretion of sodium and the role played by the different tubular segments in the regulation of sodium excretion during maturation are discussed. The influence of circulating catecholamines and renal sympathetic innervation in regulating sodium excretion during renal development is reviewed. The effects of aldosterone, atrial natriuretic factor, and prostaglandins on sodium regulation during renal maturation are discussed. Special emphasis is given to the potential role of glucocorticoids in modulating sodium excretion early in life.
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Affiliation(s)
- J E Robillard
- Department of Pediatrics, University of Iowa, Iowa City 52242
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Robillard JE, Smith FG. Endocrine control of electrolyte balance during development. BAILLIERE'S CLINICAL ENDOCRINOLOGY AND METABOLISM 1989; 3:659-69. [PMID: 2698149 DOI: 10.1016/s0950-351x(89)80047-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The endocrine control of electrolyte balance during development is reviewed. It is suggested that the high urinary sodium excretion observed in premature infants may be secondary to the immaturity of the adrenal gland to adequately increase the secretion of aldosterone (Sulyok et al, 1979b), and to the inability of the distal tubule to respond appropriately to a rise in circulating aldosterone levels (Sulyok et al, 1979a). On the other hand, the elevated plasma aldosterone levels observed in term newborn infants may play an important role in the blunted response of the newborn kidney to saline loading (Sulyok et al, 1979a; Spitzer, 1982). The ability of ANP to induce a natriuresis and to contribute to fluid and electrolyte homeostasis during development has been investigated. It has been found that the immature kidney is less responsive to ANP than later in life (Chevalier et al, 1988; Robillard et al, 1988). On the other hand, it has been suggested that a rise in plasma ANP during the first five days of life may contribute to the physiological weight loss associated with the extracellular volume contraction occurring shortly after birth (Tulassay et al, 1987). The role of glucocorticoids, prostaglandins and the kallikrein-kinin system in regulating electrolyte balance during development is also reviewed.
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Mellor DJ. Integration of perinatal events, pathophysiological changes and consequences for the newborn lamb. THE BRITISH VETERINARY JOURNAL 1988; 144:552-69. [PMID: 3060214 DOI: 10.1016/0007-1935(88)90025-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Dobrović-Jenik D, Milković S. Regulation of fetal Na+/K+-ATPase in rat kidney by corticosteroids. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 942:227-35. [PMID: 2840119 DOI: 10.1016/0005-2736(88)90024-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The enzymatic differentiation of various tissues is under hormonal control in the perinatal period. Since the regulation of Na+/K+-ATPase has not been explored prenatally, the aim of this study was to determine the corticosteroid sensitivity of sodium pump maturation in the fetal period. Na+/K+-ATPase activity was both measured in kidney homogenates of fetal rats and localized by in-situ histochemistry. Sodium pump activity was first quantifiable on day 18 of fetal development as 1.4 +/- 0.17 mumol Pi/h per mg protein, and was increased 3.4-times by day 22 of gestation. While the Na+/K+-ATPase activity was the most intense in cortical tubules at an earlier fetal age (18th and 19th day), the reaction product in the medullary tubules increased with fetal age, becoming highly intense on the 21st and 22nd day of gestation. From the 18th to 21st day of fetal development homogenate Na+/K+-ATPase activity increased as a function of chronologic age. While mineralocorticoids were without any effect on Na+/K+-ATPase activity, on the last day of the fetal development, the glucocorticoid dexamethasone proved to be successful in stimulating enzyme activity in corticosteroid-suppressed animals. According to our results, glucocorticoid hormones seem to be operating as an endogenous driving force for sodium pump maturation at the end of fetal development.
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Affiliation(s)
- D Dobrović-Jenik
- Laboratory of Pharmacology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Yugoslavia
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Abstract
We have postulated that the maturation of the renal transport mechanism for weak organic acids is controlled by thyroid and adrenal hormones. Administration of T3 and T4 (20 micrograms/100 g body wt. for 3 days) to immature rats enhanced by approximately 50% the accumulation of p-aminohippurate (PAH) in renal cortical slices of 5- to 30-day-old rats. The effect of T3 was lower, while T4 had no effect, in 50- and 105-day-old animals. Enhancement of PAH transport became apparent 24 h and disappeared by 9 days after the end of hormone treatment. Administration of a booster dose of T3 (1 microgram/100 g body wt.) on day 9 brought the level of PAH accumulation to values similar to those observed 24 h after the end of the initial 3 days of T3 administration. Dexamethasone administration (80 mg/100 g body wt. for 3 days) affected PAH uptake only in cortical slices obtained from 5-day-old rats. Changes in PAH accumulation did not correlate with changes in kidney weight or protein synthesis, indicating that they were mediated by the hormones rather than being consequent to growth.
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Affiliation(s)
- H Bräunlich
- Institut für Pharmakologie und Toxikologie der Friedrich-Schiller-Universität Jena, German Democratic Republic
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Ikegami M, Berry D, elKady T, Pettenazzo A, Seidner S, Jobe A. Corticosteroids and surfactant change lung function and protein leaks in the lungs of ventilated premature rabbits. J Clin Invest 1987; 79:1371-8. [PMID: 3571492 PMCID: PMC424392 DOI: 10.1172/jci112964] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Fetal rabbits were treated with corticosteroids by maternal administration for 48 h before delivery at 27 d gestational age. The treated and control rabbits were placed on ventilator-plethysmographs so that ventilation could be adjusted by regulation of tidal volumes to 10-13 ml/kg body wt. [125I]albumin was mixed with fetal lung fluid at birth, alternate rabbits from each litter were treated with Surfactant-TA, and [131I]albumin was injected intravascularly. The movement of the labeled albumins into and out of the alveolar wash and lung tissue was measured after 30 min of ventilation. Corticosteroid treatment (total dose, 0.2 mg/kg betamethasone) significantly decreased the protein leak across the endothelium (P less than 0.001) but increased the protein leak across the epithelium (P less than 0.001). Surfactant treatment decreased both the endothelial and epithelial leaks, and the combination of surfactant and corticosteroid treatments decreased endothelial leaks to 29% of control values and increased compliance more than either treatment alone. The 48-h corticosteroid treatment did not increase alveolar surfactant pool sizes. Corticosteroids significantly changed lung protein leaks independently of surfactant, and improved the response of the preterm lung to surfactant treatments.
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