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1.
FASEB J ; 37(9): e23120, 2023 09.
Article in English | MEDLINE | ID: mdl-37527279

ABSTRACT

The α7nAChR is crucial to the anti-inflammatory reflex, and to the expression of neuropeptides that control food intake, but its expression can be decreased by environmental factors. We aimed to investigate whether microRNA modulation could be an underlying mechanism in the α7nAchR downregulation in mouse hypothalamus following a short-term exposure to an obesogenic diet. Bioinformatic analysis revealed Let-7 microRNAs as candidates to regulate Chrna7, which was confirmed by the luciferase assay. Mice exposed to an obesogenic diet for 3 days had increased Let-7a and decreased α7nAChR levels, accompanied by hypothalamic fatty acids and TNFα content. Hypothalamic neuronal cells exposed to fatty acids presented higher Let-7a and TNFα levels and lower Chrna7 expression, but when the cells were pre-treated with TLR4 inhibitor, Let-7a, TNFα, and Chrna7 were rescued to normal levels. Thus, the fatty acids overload trigger TNFα-induced Let-7 overexpression in hypothalamic neuronal cells, which negatively regulates α7nAChR, an event that can be related to hyperphagia and obesity predisposition in mice.


Subject(s)
Tumor Necrosis Factor-alpha , alpha7 Nicotinic Acetylcholine Receptor , Animals , Mice , alpha7 Nicotinic Acetylcholine Receptor/genetics , alpha7 Nicotinic Acetylcholine Receptor/metabolism , Tumor Necrosis Factor-alpha/metabolism , Fatty Acids , Down-Regulation , Hypothalamus/metabolism
2.
Acta Obstet Gynecol Scand ; 102(12): 1730-1740, 2023 12.
Article in English | MEDLINE | ID: mdl-37697658

ABSTRACT

INTRODUCTION: With category II fetal heart rate tracings, the preferred timing of interventions to prevent fetal hypoxic brain damage while limiting operative interventions remains unclear. We aimed to estimate fetal extracellular base deficit (BDecf ) during labor with category II tracings to quantify the timing of potential interventions to prevent severe fetal metabolic acidemia. MATERIAL AND METHODS: A longitudinal study was conducted using the database of the Recurrence Prevention Committee, Japan Obstetric Compensation System for Cerebral Palsy, including infants with severe cerebral palsy born at ≥34 weeks' gestation between 2009 and 2014. Cases included those presumed to have an intrapartum onset of hypoxic-ischemic insult based on the fetal heart rate pattern evolution from reassuring to an abnormal pattern during delivery, in association with category II tracings marked by recurrent decelerations and an umbilical arterial BDecf ≥ 12 mEq/L. BDecf changes during labor were estimated based on stages of labor and the frequency/severity of fetal heart rate decelerations using the algorithm of Ross and Gala. The times from the onset of recurrent decelerations to BDecf 8 and 12 mEq/L (Decels-to-BD8, Decels-to-BD12) and to delivery were determined. Cases were divided into two groups (rapid and slow progression) based upon the rate of progression of acidosis from onset of decelerations to BDecf 12 mEq/L, determined by a finite-mixture model. RESULTS: The median Decels-to-BD8 (28 vs. 144 min, p < 0.01) and Decels-to-BD12 (46 vs. 177 min, p < 0.01) times were significantly shorter in the rapid vs slow progression. In rapid progression cases, physicians' decisions to deliver the fetus occurred at ~BDecf 8 mEq/L, whereas the "decisions" did not occur until BDecf reached 12 mEq/L in slow progression cases. CONCLUSIONS: Fetal BDecf reached 12 mEq/L within 1 h of recurrent fetal heart rate decelerations in the rapid progression group and within 3 h in the slow progression group. These findings suggest that cases with category II tracings marked by recurrent decelerations (i.e., slow progression) may benefit from operative intervention if persisting for longer than 2 h. In contrast, cases with sudden bradycardia (i.e., rapid progression) represent a challenge to prevent severe acidosis and hypoxic brain injury due to the limited time opportunity for emergent delivery.


Subject(s)
Acidosis , Brain Injuries , Cerebral Palsy , Fetal Diseases , Labor, Obstetric , Pregnancy , Infant , Female , Humans , Longitudinal Studies , Acidosis/prevention & control , Hypoxia , Heart Rate, Fetal/physiology , Cardiotocography
3.
Acta Obstet Gynecol Scand ; 100(5): 979-987, 2021 05.
Article in English | MEDLINE | ID: mdl-33247942

ABSTRACT

INTRODUCTION: Preterm infants with necrotizing enterocolitis (NEC) are at increased risk of cerebral injury and neurodevelopmental dysfunction. N-acetyl-cysteine (NAC) is a known anti-inflammatory and antioxidant agent. Currently, there is no prophylactic treatment in clinical use to prevent NEC and its neurodevelopmental sequelae. We sought to determine whether brain inflammation/apoptosis accompanies NEC systemic inflammation, and whether it can be attenuated by maternal NAC treatment during pregnancy and/or in the neonatal period in a rat model. MATERIAL AND METHODS: An established NEC newborn model (hypoxia 5% O2 for 10 min and formula feeding thrice daily, beginning on day 1 for 4 days) was used in Sprague-Dawley rat pups (n = 32). An additional group of pups (n = 33) received NAC (300 mg/kg intraperitoneal thrice daily) in addition to NEC conditions (NEC-NAC). Control pups (n = 33) were nursed and remained with the dam in room air. Two additional groups included pups of dams treated once daily with NAC (300 mg/kg intravenous) in the last 3 days of pregnancy. After birth, pups were randomized into NAC-NEC (n = 33) with NEC conditions and NAC-NEC-NAC (n = 36) with additional postnatal NAC treatment. Pups were sacrificed on the fifth day of life. Pup serum interleukin (IL)-6 protein levels, and brain nuclear factor kappa B (NF-κB) p65, neuronal nitric oxide synthase (nNOS), Caspase 3, tumor necrosis factor alpha (TNF-α), IL-6 and IL-1ß protein levels were determined by ELISA, western blot and TUNEL staining, and the groups were compared using analysis of variance (ANOVA). RESULTS: NEC pups had significantly increased serum IL-6 levels compared with the control group as well as increased neuronal apoptosis and brain protein levels of NF-κB, nNOS, Caspase 3, TNF-α, IL-6 and IL-1ß compared with control. In all NAC treatment groups, levels of serum IL-6, neuronal apoptosis and brain NF-κB, nNOS, Caspase 3, TNF-α, IL-6 and IL-1ß protein levels were significantly reduced compared with the NEC group. The most pronounced decrease was demonstrated within the NAC-NEC-NAC group. CONCLUSIONS: NAC treatment can attenuate newborn inflammatory response syndrome and decrease offspring brain neuroapoptosis and inflammation in a rat model of NEC by inhibition of NF-κB, nNOS and Caspase 3 pathways.


Subject(s)
Acetylcysteine/pharmacology , Acetylcysteine/therapeutic use , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Brain Injuries/drug therapy , Enterocolitis, Necrotizing/drug therapy , Inflammation/drug therapy , Animals , Animals, Newborn , Antioxidants/pharmacology , Antioxidants/therapeutic use , Apoptosis/drug effects , Brain Injuries/etiology , Caspase 3/metabolism , Disease Models, Animal , Enterocolitis, Necrotizing/complications , Enterocolitis, Necrotizing/prevention & control , Female , In Situ Nick-End Labeling , Inflammation/complications , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Nitric Oxide Synthase Type I/metabolism , Oxidative Stress/drug effects , Pregnancy , Rats , Rats, Sprague-Dawley , Transcription Factor RelA/metabolism , Tumor Necrosis Factor-alpha/metabolism
4.
Int J Mol Sci ; 22(24)2021 Dec 20.
Article in English | MEDLINE | ID: mdl-34948425

ABSTRACT

Perinatal hypoxia is a major cause of infant brain damage, lifelong neurological disability, and infant mortality. N-Acetyl-Cysteine (NAC) is a powerful antioxidant that acts directly as a scavenger of free radicals. We hypothesized that maternal-antenatal and offspring-postnatal NAC can protect offspring brains from hypoxic brain damage.Sixty six newborn rats were randomized into four study groups. Group 1: Control (CON) received no hypoxic intervention. Group 2: Hypoxia (HYP)-received hypoxia protocol. Group 3: Hypoxia-NAC (HYP-NAC). received hypoxia protocol and treated with NAC following each hypoxia episode. Group 4: NAC Hypoxia (NAC-HYP) treated with NAC during pregnancy, pups subject to hypoxia protocol. Each group was evaluated for: neurological function (Righting reflex), serum proinflammatory IL-6 protein levels (ELISA), brain protein levels: NF-κB p65, neuronal nitric oxide synthase (nNOS), TNF-α, and IL-6 (Western blot) and neuronal apoptosis (histology evaluation with TUNEL stain). Hypoxia significantly increased pups brain protein levels compared to controls. NAC administration to dams or offspring demonstrated lower brain NF-κB p65, nNOS, TNF-α and IL-6 protein levels compared to hypoxia alone. Hypoxia significantly increased brain apoptosis as evidenced by higher grade of brain TUNEL reaction. NAC administration to dams or offspring significantly reduce this effect. Hypoxia induced acute sensorimotor dysfunction. NAC treatment to dams significantly attenuated hypoxia-induced acute sensorimotor dysfunction. Prophylactic NAC treatment of dams during pregnancy confers long-term protection to offspring with hypoxia associated brain injury, measured by several pathways of injury and correlated markers with pathology and behavior. This implies we may consider prophylactic NAC treatment for patients at risk for hypoxia during labor.


Subject(s)
Acetylcysteine/metabolism , Asphyxia Neonatorum/complications , Brain/metabolism , Hypoxia, Brain/prevention & control , Inflammation , Oxidative Stress , Animals , Animals, Newborn , Antioxidants/metabolism , Gene Expression Regulation , Hypoxia, Brain/etiology , Hypoxia, Brain/metabolism , In Situ Nick-End Labeling , Interleukin-6/genetics , Nitric Oxide Synthase Type I/genetics , Rats , Rats, Sprague-Dawley , Transcription Factor RelA/genetics , Tumor Necrosis Factor-alpha/genetics
5.
Am J Obstet Gynecol ; 220(4): 348-353, 2019 04.
Article in English | MEDLINE | ID: mdl-30529344

ABSTRACT

Obstetricians and gynecologists belong to 1 of the medical specialties with the highest rate of litigation claims. Among birth injury cases, those cases with cerebral palsy outcomes account for litigation settlements or judgments often in the millions of dollars. In cases of potential perinatal asphyxia, a threshold level of metabolic acidosis (base deficit ≥12 mmol/L) is necessary to attribute neonatal encephalopathy to an intrapartum hypoxic event. With increasing duration or severity of a hypoxic stress resulting in metabolic acidosis, newborn infant umbilical artery base deficit increases. It may be alleged that, as base deficit levels increase beyond 12 mmol/L, there is an increased likelihood and severity of cerebral palsy. As a corollary, it may be claimed that an earlier delivery (by minutes) would reduce the base deficit and prevent or reduce the severity of cerebral palsy. This issue is of relevance to obstetricians as defendants, because retrospective "expert" analysis of cases may suggest that optimal management decisions would have resulted in an earlier delivery. In addressing the association of metabolic acidosis and cerebral palsy, base deficit should be measured as the extracellular component (base deficitextracellular fluid) rather than the commonly used base deficitblood. Studies suggest that, beyond the base deficit threshold of 12 mmol/L, the incidence and severity of cerebral palsy does not significantly increase (until ≥20 mmol/L), although the risk of neonatal death rises markedly. Thus, among most infants with hypoxia-associated neonatal encephalopathy, the occurrence of cerebral palsy is unlikely to be impacted by delivery time variation of few minutes, and this argument should not serve as the basis for medical legal claims.


Subject(s)
Acidosis/blood , Birth Injuries/blood , Cerebral Palsy/blood , Hypoxia, Brain/blood , Jurisprudence , Acidosis/epidemiology , Birth Injuries/epidemiology , Cerebral Palsy/epidemiology , Female , Fetal Blood , Humans , Hypoxia, Brain/epidemiology , Incidence , Infant, Newborn , Infant, Newborn, Diseases , Liability, Legal , Obstetrics , Pregnancy , Umbilical Arteries
6.
Am J Obstet Gynecol ; 219(1): 113.e1-113.e9, 2018 07.
Article in English | MEDLINE | ID: mdl-29709511

ABSTRACT

BACKGROUND: Maternal inflammation is a risk factor for neonatal brain injury and future neurological deficits. Pomegranates have been shown to exhibit anti-inflammatory, anti-apoptotic and anti-oxidant activities. OBJECTIVE: We hypothesized that pomegranate juice (POM) may attenuate fetal brain injury in a rat model of maternal inflammation. STUDY DESIGN: Pregnant rats (24 total) were randomized for intraperitoneal lipopolysaccharide (100 µg/kg) or saline at time 0 at 18 days of gestation. From day 11 of gestation, 12 dams were provided ad libitum access to drinking water, and 12 dams were provided ad libitum access to drinking water with pomegranate juice (5 mL per day), resulting in 4 groups of 6 dams (saline/saline, pomegranate juice/saline, saline/lipopolysaccharide, pomegranate juice/lipopolysaccharide). All dams were sacrificed 4 hours following the injection and maternal blood and fetal brains were collected from the 4 treatment groups. Maternal interleukin-6 serum levels and fetal brain caspase 3 active form, nuclear factor-κB p65, neuronal nitric oxide synthase (phosphoneuronal nitric oxide synthase), and proinflammatory cytokine levels were determined by enzyme-linked immunosorbent assay and Western blot. RESULTS: Maternal lipopolysaccharide significantly increased maternal serum interleukin-6 levels (6039 ± 1039 vs 66 ± 46 pg/mL; P < .05) and fetal brain caspase 3 active form, nuclear factor-κB p65, phosphoneuronal nitric oxide synthase, and the proinflammatory cytokines compared to the control group (caspase 3 active form 0.26 ± 0.01 vs 0.20 ± 0.01 U; nuclear factor-κB p65 0.24 ± 0.01 vs 0.1 ± 0.01 U; phosphoneuronal nitric oxide synthase 0.23 ± 0.01 vs 0.11 ± 0.01 U; interleukin-6 0.25 ± 0.01 vs 0.09 ± 0.01 U; tumor necrosis factor-α 0.26 ± 0.01 vs 0.12 ± 0.01 U; chemokine (C-C motif) ligand 2 0.23 ± 0.01 vs 0.1 ± 0.01 U). Maternal supplementation of pomegranate juice to lipopolysaccharide-exposed dams (pomegranate juice/lipopolysaccharide) significantly reduced maternal serum interleukin-6 levels (3059 ± 1121 pg/mL, fetal brain: caspase 3 active form (0.2 ± 0.01 U), nuclear factor-κB p65 (0.22 ± 0.01 U), phosphoneuronal nitric oxide synthase (0.19 ± 0.01 U) as well as the brain proinflammatory cytokines (interleukin-6, tumor necrosis factor-α and chemokine [C-C motif] ligand 2) compared to lipopolysaccharide group. CONCLUSION: Maternal pomegranate juice supplementation may attenuate maternal inflammation-induced fetal brain injury. Pomegranate juice neuroprotective effects might be secondary to the suppression of both the maternal inflammatory response and inhibition of fetal brain apoptosis, neuronal nitric oxide synthase, and nuclear factor-κB activation.


Subject(s)
Apoptosis/drug effects , Brain/drug effects , Fetus/drug effects , Fruit and Vegetable Juices , Lipopolysaccharides/pharmacology , Lythraceae , Nitric Oxide Synthase Type I/drug effects , Transcription Factor RelA/drug effects , Animals , Antioxidants , Apoptosis/immunology , Brain/immunology , Brain/metabolism , Caspase 3/drug effects , Caspase 3/metabolism , Chemokine CCL2/drug effects , Chemokine CCL2/immunology , Cytokines/drug effects , Cytokines/immunology , Dietary Supplements , Female , Fetus/immunology , Fetus/metabolism , Inflammation , Interleukin-6/immunology , NF-kappa B/drug effects , NF-kappa B/immunology , NF-kappa B/metabolism , Nitric Oxide Synthase Type I/immunology , Nitric Oxide Synthase Type I/metabolism , Oxidative Stress/drug effects , Oxidative Stress/immunology , Pregnancy , Rats , Transcription Factor RelA/immunology , Tumor Necrosis Factor-alpha/drug effects , Tumor Necrosis Factor-alpha/immunology
7.
Nature ; 488(7409): 106-10, 2012 Aug 02.
Article in English | MEDLINE | ID: mdl-22820256

ABSTRACT

Medulloblastomas are the most common malignant brain tumours in children. Identifying and understanding the genetic events that drive these tumours is critical for the development of more effective diagnostic, prognostic and therapeutic strategies. Recently, our group and others described distinct molecular subtypes of medulloblastoma on the basis of transcriptional and copy number profiles. Here we use whole-exome hybrid capture and deep sequencing to identify somatic mutations across the coding regions of 92 primary medulloblastoma/normal pairs. Overall, medulloblastomas have low mutation rates consistent with other paediatric tumours, with a median of 0.35 non-silent mutations per megabase. We identified twelve genes mutated at statistically significant frequencies, including previously known mutated genes in medulloblastoma such as CTNNB1, PTCH1, MLL2, SMARCA4 and TP53. Recurrent somatic mutations were newly identified in an RNA helicase gene, DDX3X, often concurrent with CTNNB1 mutations, and in the nuclear co-repressor (N-CoR) complex genes GPS2, BCOR and LDB1. We show that mutant DDX3X potentiates transactivation of a TCF promoter and enhances cell viability in combination with mutant, but not wild-type, ß-catenin. Together, our study reveals the alteration of WNT, hedgehog, histone methyltransferase and now N-CoR pathways across medulloblastomas and within specific subtypes of this disease, and nominates the RNA helicase DDX3X as a component of pathogenic ß-catenin signalling in medulloblastoma.


Subject(s)
Cerebellar Neoplasms/genetics , Exome/genetics , Genome, Human/genetics , Medulloblastoma/genetics , Mutation/genetics , Cerebellar Neoplasms/classification , Child , DEAD-box RNA Helicases/chemistry , DEAD-box RNA Helicases/genetics , DEAD-box RNA Helicases/metabolism , DNA Helicases/chemistry , DNA Helicases/genetics , DNA-Binding Proteins/genetics , Hedgehog Proteins/metabolism , Histone Methyltransferases , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolism , Humans , Intracellular Signaling Peptides and Proteins/genetics , LIM Domain Proteins/genetics , Medulloblastoma/classification , Models, Molecular , Neoplasm Proteins/genetics , Nuclear Proteins/chemistry , Nuclear Proteins/genetics , Patched Receptors , Patched-1 Receptor , Promoter Regions, Genetic/genetics , Protein Structure, Tertiary/genetics , Proto-Oncogene Proteins/genetics , Receptors, Cell Surface/genetics , Repressor Proteins/genetics , Signal Transduction , TCF Transcription Factors/metabolism , Transcription Factors/chemistry , Transcription Factors/genetics , Tumor Suppressor Protein p53/genetics , Wnt Proteins/metabolism , beta Catenin/genetics , beta Catenin/metabolism
8.
Environ Res ; 164: 45-52, 2018 07.
Article in English | MEDLINE | ID: mdl-29476947

ABSTRACT

In utero exposure to the ubiquitous plasticizer, bisphenol A (BPA) is associated with offspring obesity. As food intake/appetite is one of the critical elements contributing to obesity, we determined the effects of in vivo maternal BPA and in vitro BPA exposure on newborn hypothalamic stem cells which form the arcuate nucleus appetite center. For in vivo studies, female rats received BPA prior to and during pregnancy via drinking water, and newborn offspring primary hypothalamic neuroprogenitor (NPCs) were obtained and cultured. For in vitro BPA exposure, primary hypothalamic NPCs from healthy newborns were utilized. In both cases, we studied the effects of BPA on NPC proliferation and differentiation, including putative signal and appetite factors. Maternal BPA increased hypothalamic NPC proliferation and differentiation in newborns, in conjunction with increased neuroproliferative (Hes1) and proneurogenic (Ngn3) protein expression. With NPC differentiation, BPA exposure increased appetite peptide and reduced satiety peptide expression. In vitro BPA-treated control NPCs showed results that were consistent with in vivo data (increase appetite vs satiety peptide expression) and further showed a shift towards neuronal versus glial fate as well as an increase in the epigenetic regulator lysine-specific histone demethylase1 (LSD1). These findings emphasize the vulnerability of stem-cell populations that are involved in life-long regulation of metabolic homeostasis to epigenetically-mediated endocrine disruption by BPA during early life.


Subject(s)
Appetite , Prenatal Exposure Delayed Effects , Animals , Appetite/physiology , Benzhydryl Compounds , Female , Neurogenesis , Phenols , Pregnancy , Rats
10.
Am J Obstet Gynecol ; 216(3): 290.e1-290.e9, 2017 03.
Article in English | MEDLINE | ID: mdl-27836638

ABSTRACT

BACKGROUND: The obesogenic and diabetogenic effects of the environmental toxin bisphenol A during critical windows of development are well recognized. Liver and skeletal muscle play a central role in the control of glucose production, utilization, and storage. OBJECTIVES: We hypothesized that maternal bisphenol A exposure disrupts insulin signaling in rat offspring liver and skeletal muscle. We determined the protein expression of hepatic and skeletal muscle insulin signaling molecules including insulin receptor beta, its downstream target insulin receptor substrate 1 and glucose transporters (glucose transporter 2, glucose transporter 4), and hepatic glucose-regulating enzymes phosphoenolpyruvate carboxykinase and glucokinase. STUDY DESIGN: Rat dams had ad libitum access to filtered drinking water (control) or drinking water with bisphenol A from 2 weeks prior to mating and through pregnancy and lactation. Offspring litters were standardized to 4 males and 4 females and nursed by the same dam. At weaning, bisphenol A exposure was removed from all offspring. Glucose tolerance was tested at 6 weeks and 6 months. Liver and skeletal muscle was collected from 3 week old and 10 month old offspring for protein expression (Western blot) of insulin receptor beta, insulin receptor substrate 1, glucose transporter 2, glucose transporter 4, phosphoenolpyruvate carboxykinase, and glucokinase. RESULTS: Male, but not female, bisphenol A offspring had impaired glucose tolerance at 6 weeks and 6 months. Both male and female adult offspring had higher glucose-stimulated insulin secretion as well as the ratio of stimulated insulin to glucose. Male bisphenol A offspring had higher liver protein abundance of the 200 kDa insulin receptor beta precursor (2-fold), and insulin receptor substrate 1 (1.5-fold), whereas glucose transporter 2 was 0.5-fold of the control at 3 weeks of age. In adult male bisphenol A offspring, the abundance of insulin receptor beta was higher (2-fold) and glucose transporter 4 was 0.8-fold of the control in skeletal muscle. In adult female bisphenol A offspring, the skeletal muscle protein abundance of glucose transporter 4 was 0.4-fold of the control. CONCLUSION: Maternal bisphenol A had sex- and tissue-specific effects on insulin signaling components, which may contribute to increased risk of glucose intolerance in offspring. Glucose transporters were consistently altered at both ages as well as in both sexes and may contribute to glucose intolerance. These data suggest that maternal bisphenol A exposure should be limited during pregnancy and lactation.


Subject(s)
Benzhydryl Compounds/adverse effects , Insulin/physiology , Liver/drug effects , Liver/metabolism , Maternal Exposure , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Phenols/adverse effects , Protein Biosynthesis/drug effects , Signal Transduction/drug effects , Animals , Female , Male , Pregnancy , Rats , Rats, Sprague-Dawley
11.
Am J Obstet Gynecol ; 224(3): 337-338, 2021 03.
Article in English | MEDLINE | ID: mdl-33152315
13.
Am J Obstet Gynecol ; 215(3): 382.e1-6, 2016 09.
Article in English | MEDLINE | ID: mdl-27018467

ABSTRACT

BACKGROUND: Maternal magnesium administration has been shown to protect the preterm fetus from white- and gray-matter injury, although the mechanism is unknown. OBJECTIVE: The purpose of the study is to test the following hypotheses: (1) maternal infections/inflammation activate fetal neuronal N-methyl-D-aspartate receptors that up-regulate neuronal nitric oxide synthase and nuclear factor kappa-light-chain-enhancer of activated B cells pathways; and (2) maternal magnesium sulfate attenuates fetal brain neuronal nitric oxide synthase and nuclear factor kappa-light-chain-enhancer of activated B cells activation through N-methyl-D-aspartate receptors. STUDY DESIGN: Pregnant rats at embryonic day 16 and embryonic day 18 (n = 6, 48 total) received injections of intraperitoneal lipopolysaccharide 500 µg/kg or saline at time 0. Dams were randomized for treatment with subcutaneous magnesium sulfate (270 mg/kg) or saline for 2 hours prior to and following lipopolysaccharide/saline injections. At 4 hours after lipopolysaccharide administration, fetal brains were collected from the 4 treatment groups (lipopolysaccharide/saline, lipopolysaccharide/magnesium sulfate, saline/magnesium sulfate, saline/saline), and phosphoneuronal nitric oxide synthase, nuclear factor kappa-light-chain-enhancer of activated B cells p65, and chemokine (C-C motif) ligand 2 protein levels were determined by Western blot. An additional group of pregnant rats (n = 5) received N-methyl-D-aspartate-receptor antagonist following the lipopolysaccharide injection to study magnesium sulfate protective mechanism. RESULTS: Lipopolysaccharide (lipopolysaccharide/saline) significantly increased fetal brain phosphoneuronal nitric oxide synthase, nuclear factor kappa-light-chain-enhancer of activated B cells p65, and chemokine (C-C motif) ligand 2 protein levels compared to the saline/saline group at both embryonic day 16 (phosphoneuronal nitric oxide synthase 0.23 ± 0.01 vs 0.11 ± 0.01 U; nuclear factor kappa-light-chain-enhancer of activated B cells 0.24 ± 0.01 vs 0.14 ± 0.01 U; chemokine (C-C motif) ligand 2 0.28 ± 0.01 vs .01 ± 0.01 U) and embryonic day 18 (phosphoneuronal nitric oxide synthase 0.28 ± 0.01 vs 0.12 ± 0.01 U; nuclear factor kappa-light-chain-enhancer of activated B cells 0.12 ± 0.01 vs 0.1 ± 0.01 U; chemokine (C-C motif) ligand 2 0.27 ± 0.01 vs 0.11 ± 0.01 U). Magnesium sulfate treatment to lipopolysaccharide dams (lipopolysaccharide/magnesium sulfate) significantly decreased fetal brain phosphoneuronal nitric oxide synthase, nuclear factor kappa-light-chain-enhancer of activated B cells, and chemokine (C-C motif) ligand 2 protein levels compared to lipopolysaccharide/saline dams at both embryonic day 16 (neuronal nitric oxide synthase 0.17 ± 0.02 U; nuclear factor kappa-light-chain-enhancer of activated B cells 0.17 ± 0.03 U; chemokine (C-C motif) ligand 2 0.18 ± 0.01 U) and embryonic day 18 (phosphoneuronal nitric oxide synthase 0.1 ± 0.01 U; nuclear factor kappa-light-chain-enhancer of activated B cells 0.09 ± 0.01 U; chemokine (C-C motif) ligand 2 0.21 ± 0.01 U). Notably, maternal lipopolysaccharide at embryonic day 16 activated nuclear factor kappa-light-chain-enhancer of activated B cells twice as often compared to dams induced at embryonic day 18. N-methyl-D-aspartate-receptor antagonist decreased fetal brain phosphoneuronal nitric oxide synthase and nuclear factor kappa-light-chain-enhancer of activated B cells levels comparable to magnesium sulfate. CONCLUSION: Lipopolysaccharide-simulated inflammation during pregnancy may cause brain injury through activation of neuronal nitric oxide synthase and nuclear factor kappa-light-chain-enhancer of activated B cells pathways and, potentially, production of excitotoxic nitric oxide and inflammatory mediators. The increased susceptibility to brain injury in preterm fetuses may be due to enhanced nuclear factor kappa-light-chain-enhancer of activated B cells activation. Magnesium sulfate protective effects may be secondary, in part, to inhibition of neuronal nitric oxide synthase and nuclear factor kappa-light-chain-enhancer of activated B cells activation and decrease proinflammatory cytokine production through blocking nuclear factor kappa-light-chain-enhancer of activated B cells receptors.


Subject(s)
Brain/metabolism , Magnesium Sulfate/pharmacology , NF-kappa B/metabolism , Neuroprotective Agents/pharmacology , Nitric Oxide Synthase/metabolism , Animals , Chemokine CCL2/metabolism , Female , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/adverse effects , Models, Animal , Pregnancy , Rats, Sprague-Dawley
14.
Am J Obstet Gynecol ; 214(2): 270.e1-270.e8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26433172

ABSTRACT

BACKGROUND: Due to limitations of technology, clinicians are typically unable to determine if human fetuses are normoxic or moderately, chronically hypoxic. Risk factors for chronic hypoxia include fetal growth restriction, which is associated with an increased incidence of oligohydramnios and thus a risk for umbilical cord occlusion (UCO) and variable fetal heart rate (FHR) decelerations. At delivery, fetal growth restriction infants (<3rd percentile) have nearly twice the incidence of low Apgar scores and umbilical pH <7.0. Despite the risks of oligohydramnios and intermittent UCO, there is little understanding of the acid/base responses rates of chronically hypoxic fetuses to variable FHR decelerations as might occur during human labor. OBJECTIVE: We sought to compare the increase in base deficit (BD) among chronically hypoxic as compared to normoxic ovine fetuses in response to simulated mild, moderate, and severe variable FHR decelerations. STUDY DESIGN: Near-term ovine fetuses were chronically prepared with brachial artery catheters and an inflatable umbilical cuff occluder. Following a recovery period, normoxic (n = 9) and spontaneously hypoxic (n = 5) fetuses were identified (arterial O2 saturation ≤55%). Both animal groups underwent graded, 1-minute occlusions every 2.5 minutes with 1 hour of mild (∼30 beats/min [bpm] decrease from baseline), 1 hour of moderate (∼60 bpm decrease from baseline), and up to 2 hours of severe (∼90 bpm decrease from baseline) variable FHR decelerations until fetal arterial pH reached 7.00, when occlusions were stopped. RESULTS: Repetitive UCO resulted in development of acidosis (pH <7.0) in both groups. Hypoxic and normoxic fetuses demonstrated similar BD increases in response to both mild (0.39, interquartile range [IQR] 0.28-0.45 vs 0.26, IQR 0.01-0.30 mEq/L/10 min, P = .25) and severe (1.97, IQR 1.50-2.43 vs 1.51, IQR 0.97-2.45 mEq/L/10 min, P = .63) variable decelerations. However, moderate variable decelerations increased BD in hypoxic fetuses at 2.5 times the rate of normoxic fetuses (0.97, IQR 0.52-1.72 vs 0.39, IQR 0.23-0.47 mEq/L/10 min, P = .03). During the recovery period, hypoxic fetuses cleared BD slower than normoxic fetuses (0.08 ± 0.02 vs 0.12 ± 0.03 mEq/L/min, P = .02). CONCLUSION: In comparison to normoxic fetuses, hypoxic fetuses can more rapidly progress to significant metabolic acidosis in response to moderate FHR variable decelerations, and more slowly recover with in utero resuscitation, likely a consequence of impaired placental function and fetal physiologic responses.


Subject(s)
Acidosis/metabolism , Fetal Hypoxia/metabolism , Fetus/metabolism , Heart Rate, Fetal , Animals , Chronic Disease , Female , Hydrogen-Ion Concentration , Labor, Obstetric , Models, Animal , Pregnancy , Sheep , Umbilical Cord/blood supply
15.
Am J Obstet Gynecol ; 215(2): 229.e1-7, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26899904

ABSTRACT

BACKGROUND: Preterm birth remains a major cause of neonatal morbidity and mortality worldwide. Short cervical length (CL) as measured by transvaginal ultrasound (TVU) in the second trimester represents the single most predictive risk factor for spontaneous preterm birth. Previous studies have addressed, in part, the limitations of TVU availability by utilizing a cervicometer to screen patients for short cervix, identifying those patients who may not benefit from TVU CL screening. In view of the prior studies indicating that a cervicometer measurement may have a high negative predictive value (NPV) for a sonographically short cervix, we sought to identify the ideal cervicometer threshold value in a prospective, multicenter study. OBJECTIVE: The primary objective was to determine the cervicometer CL measurement threshold that provides a high NPV for the identification of patients who are highly unlikely to have a TVU CL measurement ≤20 and ≤25 mm and, therefore, may forego TVU. STUDY DESIGN: This prospective study, executed in 5 US centers, included 401 women ≥18 years of age who provided written informed consent to undergo CL measurement in the mid trimester. All women underwent both cervicometer- and TVU-measured CLs by individuals blinded to results of the other measurement. Both measurements were performed at 17-23 weeks' gestation (visit 1) and repeated at 24-29 weeks' gestation (visit 2). All TVU measurement images were reviewed by a central reader. Test characteristics and receiver operating characteristic curves were created to determine and confirm the optimal cervicometer CL threshold, maximizing the NPV. RESULTS: In all, 358 subjects were evaluable at visit 1 and 267 at visit 2. At visit 1, the average TVU CL was 38.7 ± 7.6 mm and the average cervicometer CL was 30.3 ± 8.8 mm. Similar measurements were seen at visit 2. Receiver operating characteristic curves were utilized to graphically identify a cervicometer CL threshold of 30 mm that maximized sensitivity while minimizing the false-positive rate. The 30-mm cervicometer CL threshold provided a 98-100% NPV and 0.0 negative likelihood ratio for identification of women who have a low likelihood to have a sonographic short cervix (ie, transvaginal CL ≤20 mm or ≤25 mm). The 17-23 weeks' gestation 30-mm cervicometer CL threshold has 100% sensitivity, 45-46% specificity, and 1.8 and 0.0 positive and negative likelihood ratios to predict sonographic CL ≤20 and ≤25 mm. CONCLUSION: Cervicometer CL screening successfully identifies women at low risk for short transvaginal CL. Use of a 30-mm threshold by cervicometer CL measurement confers a 98-100% NPV, with high sensitivity and moderate specificity to predict a TVU short CL. Cervicometer measurement of CL may permit almost 50% of women to avoid TVU.


Subject(s)
Cervical Length Measurement/instrumentation , Cervical Length Measurement/methods , Cervix Uteri/diagnostic imaging , Premature Birth/prevention & control , Ultrasonography/methods , Adolescent , Adult , Female , Gestational Age , Humans , Pregnancy , Prospective Studies , Risk Assessment , Sensitivity and Specificity , Young Adult
16.
Birth Defects Res A Clin Mol Teratol ; 106(12): 1008-1015, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27629527

ABSTRACT

BACKGROUND: Acardiac monochorionic twins lack cardiac function but grow by passive perfusion of the pump twin's deoxygenated arterial blood through placental arterioarterial (AA) and venovenous (VV) anastomoses and by hypoxia-mediated neovascularization. Pump twins therefore must continuously increase their cardiac output which may cause heart failure. Our aims were: to adapt our twin-twin transfusion syndrome model for acardiac twin pregnancies, to simulate pump and acardiac twin development, and to examine the model for early prognostic markers of pump twin survival. METHODS: We used an infinite acardiac placental resistance, based on placental dye injection studies and simulations, suggesting the AA-Acardiac-VV series resistance determines the pump twin's excess cardiac output. Pump and acardiac development were expressed by the pump's excess cardiac output versus its normal value, represented by pump/acardiac umbilical venous diameter (UVD) ratios. RESULTS: UVD ratios distinguish between AA-VV anastomoses that do and do not cause hydropic pump twins. Pump twins can handle relative larger acardiac perfusion at later than earlier gestation. Both VV and acardiac resistances are significantly smaller than the AA resistance, based on respectively clinical data and acardiac blood volumetric growth. CONCLUSION: Our simulations support clinical results which show that UVD ratios aid in the prediction of pump twin risk. The AA anastomosis controls the future of both the pump and the acardiac. Correlation between acardiac size and pump twin risk is secondary to the AA size but remains clinically usable. These factors may aid in the development of methods for pump twin prognosis and the promotion of selective clinical interventions.Birth Defects Research (Part A), 2016.© 2016 Wiley Periodicals, Inc. Birth Defects Research (Part A) 106:1008-1015, 2016. © 2016 Wiley Periodicals, Inc.


Subject(s)
Diseases in Twins/physiopathology , Heart Defects, Congenital/physiopathology , Models, Cardiovascular , Neovascularization, Pathologic/physiopathology , Placenta/blood supply , Twins, Monozygotic , Cardiac Output , Computer Simulation , Diseases in Twins/pathology , Female , Fetus , Heart Defects, Congenital/pathology , Humans , Neovascularization, Pathologic/pathology , Placenta/abnormalities , Placental Circulation , Pregnancy , Pregnancy, Twin , Umbilical Veins/pathology , Umbilical Veins/physiopathology
17.
Appetite ; 99: 193-199, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-26785315

ABSTRACT

Maternal overnutrition results in programmed offspring obesity, mediated in part, by hyperphagia. This is remarkably similar to the effects of maternal undernutrition on offspring hyperphagia and obesity. In view of the marked differences in the energy environment of the over and under-nutrition exposures, we studied the expression of select epigenetic modifiers associated with energy imbalance including neurogenic factors and appetite/satiety neuropeptides which are indicative of neurogenic differentiation. HF offspring were exposed to maternal overnutrition (high fat diet; HF) during pregnancy and lactation. We determined the protein expression of energy sensors (mTOR, pAMPK), epigenetic factors (DNA methylase, DNMT1; histone deacetylase, SIRT1/HDAC1), neurogenic factors (Hes1, Mash1, Ngn3) and appetite/satiety neuropeptides (AgRP/POMC) in newborn hypothalamus and adult arcuate nucleus (ARC). Despite maternal obesity, male offspring born to obese dams had similar body weight at birth as Controls. However, when nursed by the same dams, male offspring of obese dams exhibited marked adiposity. At 1 day of age, HF newborn males had significantly decreased energy sensors, DNMT1 including Hes1 and Mash1, which may impact neuroprogenitor cell proliferation and differentiation. This is consistent with increased AgRP in HF newborns. At 6 months of age, HF adult males had significantly increased energy sensors and decreased histone deactylases. In addition, the persistent decreased Hes1, Mash1 as well as Ngn3 are consistent with increased AgRP and decreased POMC. Thus, altered energy sensors and epigenetic responses which modulate gene expression and adult neuronal differentiation may contribute to hyperphagia and obesity in HF male offspring.


Subject(s)
Hyperphagia/physiopathology , Hypothalamus/metabolism , Malnutrition/physiopathology , Maternal Nutritional Physiological Phenomena , Adiposity , Agouti-Related Protein/genetics , Agouti-Related Protein/metabolism , Animals , Animals, Newborn , Appetite/physiology , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Body Weight , Cell Differentiation/drug effects , Cell Proliferation/drug effects , DNA (Cytosine-5-)-Methyltransferase 1 , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA (Cytosine-5-)-Methyltransferases/metabolism , Diet, High-Fat , Energy Intake , Epigenesis, Genetic , Female , Hyperphagia/etiology , Hyperphagia/genetics , Male , Malnutrition/complications , Malnutrition/genetics , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Obesity/etiology , Obesity/genetics , Obesity/physiopathology , Pregnancy , Rats , Satiation/physiology , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism , Transcription Factor HES-1/genetics , Transcription Factor HES-1/metabolism
18.
Am J Obstet Gynecol ; 213(6): 851.e1-8, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26232507

ABSTRACT

OBJECTIVE: Maternal chorioamnionitis is associated with newborn neurologic injury. Recent evidence suggests that maternal administration of magnesium sulphate (MG) may protect fetuses from white matter injury. Previously we demonstrated evidence by magnetic resonance imaging that MG may prevent maternal inflammation-induced gray matter injury of offspring. Thus, we sought to determine the potential of maternal inflammation to induce fetal neurological/behavioral deficits and assess whether maternal MG attenuates these effects. STUDY DESIGN: Pregnant rats at day 18 received injections of intraperitoneal lipopolysaccharide (LPS) or saline. Dams were treated with subcutaneous saline/MG (270 mg/kg followed by 27 mg/kg every 20 minutes) for 2 hours before and following LPS/saline injections. Pups were delivered spontaneously. At 1 and 3 months of age, 11-12 offspring of each group (saline, LPS, MG, LPS-MG) underwent a 2-way shuttle box avoidance testing. The shuttle box is divided in half and the animal moves between compartments to avoid an electric shock in response to an auditory stimulus. RESULTS: Control offspring demonstrated significantly improved learning and memory abilities from age 1 to 3 months. At 1 month, LPS-treated dams' offspring were similar to controls with no improvement in learning abilities at 3 months. MG treatment of LPS dams significantly improved offspring learning at 3 months, to equal or better than that of controls. CONCLUSION: LPS-stimulated inflammation during pregnancy impairs offspring learning ability and memory, which is ameliorated by maternal MG treatment. These results suggest that maternal MG therapy may prevent white and gray matter injuries associated with maternal infection/inflammation.


Subject(s)
Avoidance Learning/drug effects , Magnesium Sulfate/administration & dosage , Memory, Short-Term/drug effects , Neuroprotective Agents/administration & dosage , Animals , Animals, Newborn , Chorioamnionitis/drug therapy , Escape Reaction/drug effects , Female , Injections, Subcutaneous , Lipopolysaccharides/adverse effects , Pregnancy , Rats, Sprague-Dawley
20.
Am J Obstet Gynecol ; 211(3): 237.e1-237.e13, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24631702

ABSTRACT

OBJECTIVE: We determined the potential programming effects of maternal obesity and high-fat (HF) diet during pregnancy and/or lactation on offspring metabolic syndrome. STUDY DESIGN: A rat model of maternal obesity was created using an HF diet prior to and throughout pregnancy and lactation. At birth, pups were cross-fostered, thereby generating 4 paradigms of maternal diets during pregnancy/lactation: (1) control (Con) diet during pregnancy and lactation (Con/Con), (2) HF during pregnancy and lactation (HF/HF), (3) HF during pregnancy alone (HF/Con), and (4) HF during lactation alone (Con/HF). RESULTS: Maternal phenotype during pregnancy and the end of lactation evidenced markedly elevated body fat and plasma corticosterone levels in HF dams. In the offspring, the maternal HF diet during pregnancy alone programmed increased offspring adiposity, although with normal body weight, whereas the maternal HF diet during lactation increased both body weight and adiposity. Metabolic disturbances, particularly that of hyperglycemia, were apparent in all groups exposed to the maternal HF diet (during pregnancy and/or lactation), although differences were apparent in the manifestation of insulin resistant vs insulin-deficient phenotypes. Elevated systolic blood pressure was manifest in all groups, implying that exposure to an obese/HF environment is disadvantageous for offspring health, regardless of pregnancy or lactation periods. Nonetheless, the underlying mechanism may differ because offspring that experienced in utero HF exposure had increased corticosterone levels. CONCLUSION: Maternal obesity/HF diet has a marked impact on offspring body composition and the risk of metabolic syndrome was dependent on the period of exposure during pregnancy and/or lactation.


Subject(s)
Maternal Nutritional Physiological Phenomena , Metabolic Syndrome/etiology , Obesity/complications , Animals , Body Composition , Corticosterone/blood , Diet, High-Fat , Eating , Female , Lactation , Lipids/blood , Male , Pregnancy , Rats , Rats, Sprague-Dawley
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