Microbial Translocation and Perinatal Asphyxia/Hypoxia: A Systematic Review

Effects of hypothermia and hypoxia on cytochrome P450-mediated drug metabolism in neonatal Göttingen minipigs

Asphyxiated neonates often undergo therapeutic hypothermia (TH) to reduce morbidity and mortality. As perinatal asphyxia and TH impact neonatal physiology, this could also influence enzyme functionality. Therefore, this study aimed to unravel the impact of age, hypothermia and hypoxia on porcine hepatic cytochrome P450 (CYP) gene expression, protein abundance and activity. Hepatic CYP expression, protein abundance and activity were assessed in naive adult and neonatal Göttingen minipigs, alongside those from an (non-survival) in vivo study, where four conditions-control (C), therapeutic hypothermia (TH), hypoxia (H), hypoxia and TH (H + TH)-were examined. Naive neonatal Göttingen minipigs exhibited 75% lower general CYP activity and different gene expression patterns than adults. In vitro hypothermia (33°C) decreased general CYP activity in adult liver microsomes by 36%. Gene expression was not different between TH and C while hypoxia up-regulated several genes (i.e., CYP3A29 [expression ratio; ER = 5.1472] and CYP2C33 [ER = 3.2292] in the H group and CYP2C33 [ER = 2.4914] and CYP2C42 [ER = 4.0197] in the H + TH group). The medical treatment and the interventions over 24 h, along with hypoxia and TH, affected the protein abundance. These data on CYP expression, abundance and activity in young animals can be valuable in building physiologically-based pharmacokinetic models for neonatal drug dose predictions.

The Impact of Gestational Diabetes Mellitus (GDM) on the Development and Composition of the Neonatal Gut Microbiota: A Systematic Review

Gestational diabetes mellitus (GDM) is an important health issue, as it is connected with adverse effects to the mother as well as the fetus. A factor of essence for the pathology of this disorder is the gut microbiota, which seems to have an impact on the development and course of GDM. The role of the gut microbiota on maternal reproductive health and all the changes that happen during pregnancy as well as during the neonatal period is of high interest. The correct establishment and maturation of the gut microbiota is of high importance for the development of basic biological systems. The aim of this study is to provide a systematic review of the literature on the effect of GDM on the gut microbiota of neonates, as well as possible links to morbidity and mortality of neonates born to mothers with GDM. Systematic research took place in databases including PubMed and Scopus until June 2024. Data that involved demographics, methodology, and changes to the microbiota were derived and divided based on patients with exposure to or with GDM. The research conducted on online databases revealed 316 studies, of which only 16 met all the criteria and were included in this review. Research from the studies showed great heterogeneity and varying findings at the level of changes in α and β diversity and enrichment or depletion in phylum, gene, species, and operational taxonomic units in the neonatal gut microbiota of infants born to mothers with GDM. The ways in which the microbiota of neonates and infants are altered due to GDM remain largely unclear and require further investigation. Future studies are needed to explore and clarify these mechanisms.

Drug Disposition in Neonatal Göttingen Minipigs: Exploring Effects of Perinatal Asphyxia and Therapeutic Hypothermia

Asphyxiated neonates often undergo therapeutic hypothermia (TH) to reduce morbidity and mortality. Since both perinatal asphyxia (PA) and TH influence physiology, altered pharmacokinetics (PK) and pharmacodynamics (PD) are expected. Given that TH is the standard of care for PA with moderate to severe hypoxic-ischemic encephalopathy, disentangling the effect of PA versus TH on PK/PD is not possible in clinical settings. However, animal models can provide insights into this matter. The (neonatal) Göttingen Minipig, the recommended strain for nonclinical drug development, was selected as translational model. Four drugs-midazolam (MDZ), fentanyl (FNT), phenobarbital (PHB), and topiramate (TPM)-were intravenously administered under four conditions: control (C), therapeutic hypothermia (TH), hypoxia (H), and hypoxia plus TH (H+TH). Each group included six healthy male neonatal Göttingen Minipigs anesthetized for 24 hours. Blood samples were drawn at 0 (predose) and 0.5, 2, 2.5, 3, 4, 4.5, 6, 8, 12, and 24 hours post drug administration. Drug plasma concentrations were determined using validated bioanalytical assays. The PK parameters were estimated through compartmental and noncompartmental PK analysis. The study showed a statistically significant decrease in FNT clearance (CL; 66% decrease), with an approximately threefold longer half-life (t1/2) in the TH group. The H+TH group showed a 17% reduction in FNT CL, with a 62% longer t1/2 compared with the C group; however, it was not statistically significant. Although not statistically significant, trends toward lower CL and longer t1/2 were observed in the TH and H+TH groups for MDZ and PHB. Additionally, TPM demonstrated a 28% decrease in CL in the H group compared with controls. SIGNIFICANCE STATEMENT: The overarching goal of this study using the neonatal Göttingen Minipig model was to disentangle the effects of systemic hypoxia and TH on PK using four model drugs. Such insights can subsequently be used to inform and develop a physiologically based pharmacokinetic model, which is useful for drug exposure prediction in human neonates.

Clinical characteristics, seizure control, and delivery outcomes in pregnant women with focal and generalized epilepsies

OBJECTIVE

To prospectively investigate the course of epilepsy and assess seizure control during pregnancy in women with focal epilepsy (FE) compared with generalized epilepsy (GE), to ascertain the effects of epilepsy and its types on delivery and neonatal outcomes, and to compare adverse outcomes between pregnancies complicated by epilepsy and normal pregnancies.

METHODS

124 pregnant women with epilepsy (WWE) were enrolled in a prospective study. Obstetric and neonatal outcomes were compared with those of 277 healthy women in the control group.

RESULTS

Occurrence of seizures during pregnancy was more often in FE (77.1 %) compared with GE (50.0 %) (Odds ratio [OR] 2.08; 95 % confidence interval [CI] 0.97-4.46, p = 0.06); the overall seizure freedom was significantly higher in women with GE compared with women with FE (p = 0.0038). Poor seizure control one year prior to the pregnancy and nonadherence to treatment were significantly associated with presence of seizures during pregnancy (p < 0.0001). Compared with pregnancies of women without epilepsy, WWE were at increased risk of cesarean section (CS) (p < 0.0001) and preterm birth (p = 0.03). Offspring of mothers with epilepsy were at higher risks of Apgar scores at 5 min ≤7 (p < 0.0001) and perinatal hypoxia (p = 0.03) compared with infants of unaffected women. Seizures during pregnancy were significantly correlated with the higher rate of CS, Apgar scores at 5 min ≤7, and perinatal hypoxia (p = 0.0069; p = 0.0098; and p = 0.0045, respectively). The risks of adverse outcomes were not significantly increased in women with FE compared to women with GE.

CONCLUSION

Epileptic seizures in pregnancy are associated with increased risks of adverse delivery and neonatal outcomes. Hence, early assessment of seizure disorder, adequate seizure control prior to and during pregnancy, and effective treatment are required to prevent potential seizure-related complications and improve maternal and fetal outcomes.

Henriques T. Machine learning models based on clinical indices and cardiotocographic features for discriminating asphyxia fetuses—Porto retrospective intrapartum study

Introduction

Perinatal asphyxia is one of the most frequent causes of neonatal mortality, affecting approximately four million newborns worldwide each year and causing the death of one million individuals. One of the main reasons for these high incidences is the lack of consensual methods of early diagnosis for this pathology. Estimating risk-appropriate health care for mother and baby is essential for increasing the quality of the health care system. Thus, it is necessary to investigate models that improve the prediction of perinatal asphyxia. Access to the cardiotocographic signals (CTGs) in conjunction with various clinical parameters can be crucial for the development of a successful model.

Objectives

This exploratory work aims to develop predictive models of perinatal asphyxia based on clinical parameters and fetal heart rate (fHR) indices.

Methods

Single gestations data from a retrospective unicentric study from Centro Hospitalar e Universitário do Porto de São João (CHUSJ) between 2010 and 2018 was probed. The CTGs were acquired and analyzed by Omniview-SisPorto, estimating several fHR features. The clinical variables were obtained from the electronic clinical records stored by ObsCare. Entropy and compression characterized the complexity of the fHR time series. These variables' contribution to the prediction of asphyxia perinatal was probed by binary logistic regression (BLR) and Naive-Bayes (NB) models.

Results

The data consisted of 517 cases, with 15 pathological cases. The asphyxia prediction models showed promising results, with an area under the receiver operator characteristic curve (AUC) &gt;70%. In NB approaches, the best models combined clinical and SisPorto features. The best model was the univariate BLR with the variable compression ratio scale 2 (CR2) and an AUC of 94.93% [94.55; 95.31%].

Conclusion

Both BLR and Bayesian models have advantages and disadvantages. The model with the best performance predicting perinatal asphyxia was the univariate BLR with the CR2 variable, demonstrating the importance of non-linear indices in perinatal asphyxia detection. Future studies should explore decision support systems to detect sepsis, including clinical and CTGs features (linear and non-linear).

Asphyxia-Induced Bacterial Translocation in an Animal Experimental Model in Neonatal Piglets

BACKGROUND

The term "bacterial translocation" (BT) refers to the migration of bacteria or their products from the gastrointestinal tract to tissues located outside it, and may occur after intestinal ischemia-reperfusion injury. The term "endotoxin" is synonymous, and is used interchangeably with the term lipopolysaccharide (LPS). LPS, a component of Gram-negative gut bacteria, is a potent microbial virulence factor, that can trigger production of pro-inflammatory mediators, causing localized and systemic inflammation. The aim of this study is to investigate if neonatal asphyxia provokes BT and an increased concentration of LPS in an animal model of asphyxia in piglets.

METHODS

Twenty-one (21) newborn male Landrace/Large White piglets, 1-4 days old, were randomly allocated into three groups, Control (A), Asphyxia (B) and Asphyxia-Cardiopulmonary Resuscitation (CPR) (C). All animals were instrumented, anesthetized and underwent hemodynamic monitoring. In Group A, the animals were euthanized. In Group B, the endotracheal tube was occluded to cause asphyxia leading to cardiopulmonary arrest. In Group C, the animals were resuscitated after asphyxia and further monitored for 30'. Bacterial translocation was assessed by the measurement of endotoxin in blood from the portal vein and the aorta, and also by the measurement of endotoxin in mesenteric lymph nodes (MLNs) at euthanasia. The results are given as median (IQR) with LPS concentration in EU/mL.

RESULTS

BT was observed in all groups with minimum LPS concentration in the MLN and maximum concentration in the portal vein. LPS levels in the MLNs were higher in the Group B: 6.38 EU/mL (2.69-9.34) compared to the other groups (Group A: 2.1 EU/mL (1.08-2.52), Group C: 1.66 EU/mL (1.51-2.48), p = 0.012). The aorta to MLNs LPS difference (%) was lower in Group B: 0.13% (0.04-1.17), compared to Group A: 5.08% (2.2-10.7), and Group C: 3.42% (1.5-5.1)) (p = 0.042). The same was detected for portal to MLNs LPS difference (%) which was lower in Group B: 0.94% (0.5-3) compared to Group A: 4.9% (4-15), and Group C: 3.85% (1.5-5.1)) (p = 0.044).

CONCLUSIONS

Neonatal asphyxia can provoke ΒΤ and increased LPS concentration in blood and tissue located outside the gastrointestinal system.

Is acidemia at birth a risk factor for functional gastrointestinal disorders?

Functional gastrointestinal disorders (FGIDs) are common in early childhood. It has been demonstrated that neonatal acidemia at delivery can lead to significant neonatal morbidity. The primary aim of this study was to evaluate the relationship between acidemia at birth and the development of FGIDs, as regurgitation, colic, and constipation, in term infants. Term newborns born at the Foggia University Hospital, Italy during the year 2020 were included in the study. As per routine clinical practice, a cord blood gas analysis on a blood sample drawn from the umbilical artery (UA) of each infant immediately after birth was performed, and Apgar score was recorded. One year after birth, each infant's parents were interviewed through a phone call to investigate development of FGIDs, feeding practices, and morbidities. During the study period, 1574 term newborns met the inclusion criteria. The prevalence of infantile colic, regurgitation, and constipation was higher in infants with low UA pH (colic 51.5% vs. 25.4%, p < 0.001; regurgitation 30.6% vs. 15.2%, p < 0.001; constipation 24.6% vs. 16.0%, p = 0.015), with infants having moderate-severe acidemia facing the highest risk for all the examined FGIDs. In binary logistic regression analyses, UA pH and perinatal antibiotic exposure proved to be independently associated with the later diagnosis of each FGID.

CONCLUSION

Newborns with acidemia at birth appear to face a higher risk of FGIDs in infancy. Avoiding low cord blood pH should continue to be the goal for obstetricians, while enhanced long-term surveillance for infants who experienced birth acidemia should be required.

WHAT IS KNOWN

• Cord blood gas analysis is recommended in all high-risk deliveries, and in some centers, it is performed after all deliveries. • Neonatal acidemia at birth has been linked to adverse outcomes, mainly neurological. Recently, perinatal asphyxia has been reported to increase the risk of developing necrotizing enterocolitis in term infants.

WHAT IS NEW

• An association between acidemia at birth and risk of developing FGIDs such as regurgitation and colic during the first year of life had never been described so far. • An increased surveillance of infants with low UA pH at birth may be beneficial and could allow for early detection of any of the reported FGIDs.

Predictive Value of Heat-Shock Protein Gene Expression on Severe Neonatal Hypoxic-Ischemic Encephalopathy

This study aims to evaluate significant gene expression in severe hypoxic ischemic encephalopathy (HIE) in newborns, which can be used as a predictable measure for high-risk HIE infants. The study prospectively recruited 77 inborn near-term or term HIE newborns between January 2018 and December 2020. We measured six different genes within 6 h of life among the HIE infants and compared the gene levels between the mild- and severe-HIE groups. Among these, 64 HIE infants (83.1%) did not receive therapeutic hypothermia (TH) because they were categorized as mild HIE, and the 13 remaining (16.9%) infants were categorized as ≥ moderate-HIE group and received TH. More abnormal MRI findings, seizure, and use of anti-convulsant were more found in the ≥ moderate = HIE group along with longer mechanical ventilation days and hospitalization. Heat-shock protein 70 family 1 A (HSPA1A) and serpin family H member 1 (SERPINH1) genes, which encode heat-shock protein (HSP) 70 and 47, respectively, were significantly elevated in the ≥ moderate-HIE, seizure, and abnormal MRI groups. HSP 70 and 47 were significantly elevated in the severe-HIE group, possibly playing protective roles in inhibiting exacerbated neuroinflammation and maintaining a cellular homeostasis. At 18–24 months, ≥ moderate-HIE group manifested a significant language delay.

Development of the Gastrointestinal Tract in Newborns as a Challenge for an Appropriate Nutrition: A Narrative Review

The second and third trimesters of pregnancy are crucial for the anatomical and functional development of the gastrointestinal (GI) tract. If premature birth occurs, the immaturity of the digestive and absorptive processes and of GI motility represent a critical challenge to meet adequate nutritional needs, leading to poor extrauterine growth and to other critical complications. Knowledge of the main developmental stages of the processes involved in the digestion and absorption of proteins, carbohydrates, and lipids, as well as of the maturational phases underlying the development of GI motility, may aid clinicians to optimize the nutritional management of preterm infants. The immaturity of these GI systems and functions may negatively influence the patterns of gut colonization, predisposing to an abnormal microbiome. This, in turn, further contributes to alter the functional, immune, and neural development of the GI tract and, especially in preterm infants, has been associated with an increased risk of severe GI complications, such as necrotizing enterocolitis. Deeper understanding of the physiological colonization patterns in term and preterm infants may support the promotion of these patterns and the avoidance of microbial perturbations associated with the development of several diseases throughout life. This review aims to provide a global overview on the maturational features of the main GI functions and on their implications following preterm birth. We will particularly focus on the developmental differences in intestinal digestion and absorption functionality, motility, gut–brain axis interaction, and microbiomes.