Preterm birth and sustained inflammation: consequences for the neonate

Arachidonic acid and docosahexaenoic acid levels correlate with the inflammation proteome in extremely preterm infants

BACKGROUND & AIM

Clinical trials supplementing the long-chain polyunsaturated fatty acids (LCPUFAs) docosahexaenoic acid (DHA) and arachidonic acid (AA) to preterm infants have shown positive effects on inflammation-related morbidities, but the molecular mechanisms underlying these effects are not fully elucidated. This study aimed to determine associations between DHA, AA, and inflammation-related proteins during the neonatal period in extremely preterm infants.

METHODS

A retrospective exploratory study of infants (n = 183) born below 28 weeks gestation from the Mega Donna Mega trial, a randomized multicenter trial designed to study the effect of DHA and AA on retinopathy of prematurity. Serial serum samples were collected after birth until postnatal day 100 (median 7 samples per infant) and analyzed for phospholipid fatty acids and proteins using targeted proteomics covering 538 proteins. Associations over time between LCPUFAs and proteins were explored using mixed effect modeling with splines, including an interaction term for time, and adjusted for gestational age, sex, and center.

RESULTS

On postnatal day one, 55 proteins correlated with DHA levels and 10 proteins with AA levels. Five proteins were related to both fatty acids, all with a positive correlation. Over the first 100 days after birth, we identified 57 proteins to be associated with DHA and/or AA. Of these proteins, 41 (72%) related to inflammation. Thirty-eight proteins were associated with both fatty acids and the overall direction of association did not differ between DHA and AA, indicating that both LCPUFAs similarly contribute to up- and down-regulation of the preterm neonate inflammatory proteome. Primary examples of this were the inflammation-modulating cytokines IL-6 and CCL7, both being negatively related to levels of DHA and AA in the postnatal period.

CONCLUSIONS

This study supports postnatal non-antagonistic and potentially synergistic effects of DHA and AA on the inflammation proteome in preterm infants, indicating that supplementation with both fatty acids may contribute to limiting the disease burden in this vulnerable population.

CLINICAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT03201588).

Impact of preterm birth on muscle mass and function: a systematic review and meta-analysis

Individuals born preterm present lower exercise capacity. Along with the cardiopulmonary responses and activity level, muscle strength is a key determinant of exercise capacity. This systematic review aimed to summarize the current knowledge on the impact of preterm birth on skeletal muscle mass and function across the lifespan. The databases PubMed, MEDLINE, EBM, Embase, CINAHL Plus, Global Index Medicus, and Google Scholar were searched using keywords and MeSH terms related to skeletal muscle, preterm birth, and low birth weight. Two independent reviewers undertook study selection, data extraction, and quality appraisal using Covidence review management. Data were pooled to estimate the prematurity effect on muscle mass and function using the R software. From 4378 studies retrieved, 132 were full-text reviewed and 25 met the inclusion/exclusion criteria. Five studies presented a low risk of bias, and 5 had a higher risk of bias due to a lack of adjustment for confounding factors and presenting incomplete outcomes. Meta-analyses of pooled data from homogenous studies indicated a significant reduction in muscle thickness and jump test (muscle power) in individuals born preterm versus full-term with standardized mean difference and confidence interval of - 0.58 (0.27, 0.89) and - 0.45 (0.21, 0.69), respectively.    Conclusion: Overall, this systematic review summarizing the existing literature on the impact of preterm birth on skeletal muscle indicates emerging evidence that individuals born preterm, display alteration in the development of their skeletal muscle mass and function. This work also highlights a clear knowledge gap in understanding the effect of preterm birth on skeletal muscle development. What is Known: • Preterm birth, which occurs at a critical time of skeletal muscle development and maturation, impairs the development of different organs and tissues leading to a higher risk of comorbidities such as cardiovascular diseases. • Preterm birth is associated with reduced exercise capacity. What is New: • Individuals born preterm display alterations in muscle mass and function compared to individuals born at term from infancy to adulthood. • There is a need to develop preventive or curative interventions to improve skeletal muscle health in preterm-born individuals.

The role of placental insufficiency in spontaneous preterm birth: A literature review

Preterm Birth (delivery before 37 weeks of gestation) is the leading cause of childhood mortality and is also associated with significant morbidity both in the neonatal period and beyond. The aetiology of spontaneous preterm birth is unclear and likely multifactorial incorporating factors such as infection/inflammation and cervical injury. Placental insufficiency is emerging as an additional contributor to spontaneous preterm delivery; however, the mechanisms by which this occurs are not fully understood. Serum biomarkers and imaging techniques have been investigated as potential predictors of placental insufficiency, however none have yet been found to have a sufficient predictive value. This review examines the evidence for the role of the placenta in preterm birth, preterm prelabour rupture of the membranes and abruption as well as highlighting areas where further research is required.

Human chorionic gonadotropin decreases cerebral cystic encephalomalacia and parvalbumin interneuron degeneration in a pro-inflammatory model of mouse neonatal hypoxia-ischemia

The pregnancy hormone, human chorionic gonadotropin (hCG) is an immunoregulatory and neurotrophic glycoprotein of potential clinical utility in the neonate at risk for cerebral injury. Despite its well-known role in its ability to modulate the innate immune response during pregnancy, hCG has not been demonstrated to affect the pro-degenerative actions of inflammation in neonatal hypoxia-ischemia (HI). Here we utilize a neonatal mouse model of mild HI combined with intraperitoneal administration of lipopolysaccharide (LPS) to evaluate the neuroprotective actions of hCG in the setting of endotoxin-mediated systemic inflammation. Intraperitoneal treatment of hCG shortly prior to LPS injection significantly decreased tissue loss and cystic degeneration in the hippocampal and cerebral cortex in the term-equivalent neonatal mouse exposed to mild HI. Noting that parvalbumin immunoreactive interneurons have been broadly implicated in neurodevelopmental disorders, it is notable that hCG significantly improved the injury-mediated reduction of these neurons in the cerebral cortex, striatum and hippocampus. The above findings were associated with a decrease in the amount of Iba1 immunoreactive microglia in most of these brain regions. These observations implicate hCG as an agent capable of improving the neurological morbidity associated with peripheral inflammation in the neonate affected by HI. Future preclinical studies should aim at demonstrating added neuroprotective benefit by hCG in the context of therapeutic hypothermia and further exploring the mechanisms responsible for this effect. This research is likely to advance the therapeutic role of gonadotropins as a treatment for neonates with neonatal brain injury.

Risk of adverse perinatal outcomes among women with clinical and subclinical histopathological chorioamnionitis

Introduction

Histologic chorioamnionitis (HCA) is a placental inflammatory condition associated with adverse perinatal outcomes (APOs). This historical cohort study explores the risk of APOs in pregnant women with HCA and compares the impact of clinical chorioamnionitis (CCA) with subclinical chorioamnionitis (SCCA).

Methodology

Placentas were evaluated by a perinatal pathologist tand all women with HCA were included. Two groups were integrated: (1) women with clinical chorioamnionitis (CCA) and (2) women with subclinical chorioamnionitis (SCCA). Additionally, we conducted a secondary analysis to compare the prevalence of APOs among stage 1, 2 and 3 of HCA and the risk of APOs between grades 1 and 2 of HCA. The APOs analyzed were preterm birth, stillbirth, neonatal weight < 1,500 g, neonatal sepsis. Relative risk with 95% confidence interval was calculated.

Results

The study included 41 cases of CCA and 270 cases of SCCA. The mean gestational age at diagnosis and birth was 30.2 ± 5.4 weeks and 32.5 ± 5.1 weeks, for group 1 and 2, respectively. The study also found that women with HCA stage 3 and grade 2 had a higher prevalence and risk of adverse perinatal outcomes.

Discussion

The findings of this study suggest the importance of placental histological study to excluded SCCA, which represents a significant risk to both maternal and neonatal health, contributing to high morbidity and mortality.

Key roles of glial cells in the encephalopathy of prematurity

Across the globe, approximately one in 10 babies are born preterm, that is, before 37 weeks of a typical 40 weeks of gestation. Up to 50% of preterm born infants develop brain injury, encephalopathy of prematurity (EoP), that substantially increases their risk for developing lifelong defects in motor skills and domains of learning, memory, emotional regulation, and cognition. We are still severely limited in our abilities to prevent or predict preterm birth. No longer just the "support cells," we now clearly understand that during development glia are key for building a healthy brain. Glial dysfunction is a hallmark of EoP, notably, microgliosis, astrogliosis, and oligodendrocyte injury. Our knowledge of glial biology during development is exponentially expanding but hasn't developed sufficiently for development of effective neuroregenerative therapies. This review summarizes the current state of knowledge for the roles of glia in infants with EoP and its animal models, and a description of known glial-cell interactions in the context of EoP, such as the roles for border-associated macrophages. The field of perinatal medicine is relatively small but has worked passionately to improve our understanding of the etiology of EoP coupled with detailed mechanistic studies of pre-clinical and human cohorts. A primary finding from this review is that expanding our collaborations with computational biologists, working together to understand the complexity of glial subtypes, glial maturation, and the impacts of EoP in the short and long term will be key to the design of therapies that improve outcomes.

Predictors of upstream inflammation and oxidative stress pathways during early pregnancy

BACKGROUND

Inflammation and oxidative stress are critical to pregnancy, but most human study has focused on downstream, non-causal indicators. Oxylipins are lipid mediators of inflammation and oxidative stress that act through many biological pathways. Our aim was to characterize predictors of circulating oxylipin concentrations based on maternal characteristics.

METHODS

Our study was conducted among 901 singleton pregnancies in the LIFECODES Fetal Growth Study, a nested case-cohort with recruitment from 2007 to 2018. We measured a targeted panel of oxylipins in early pregnancy plasma and urine samples from several biosynthetic pathways, defined by the polyunsaturated fatty acid (PUFA) precursor and enzyme group. We evaluated levels across predictors, including characteristics of participants' pregnancy, socioeconomic determinants, and obstetric and medical history.

RESULTS

Current pregnancy and sociodemographic characteristics were the most important predictors of circulating oxylipins concentrations. Plasma oxylipins were lower and urinary oxylipins higher for participants with a later gestational age at sampling (13-23 weeks), higher prepregnancy BMI (obesity class I, II, or III), Black or Hispanic race and ethnicity, and lower socioeconomic status (younger age, lower education, and uninsured). For example, compared to those with normal or underweight prepregnancy BMI, participants with class III prepregnancy obesity had 45-46% lower plasma epoxy-eicosatrienoic acids, the anti-inflammatory oxylipins produced from arachidonic acid (AA) by cytochrome P450, and had 81% higher urinary 15-series F2-isoprostanes, an indicator of oxidative stress produced from non-enzymatic AA oxidation. Similarly, in urine, Black participants had 92% higher prostaglandin E2 metabolite, a pro-inflammatory oxylipin, and 41% higher 5-series F2-isoprostane, an oxidative stress indicator.

CONCLUSIONS

In this large pregnancy study, we found that circulating levels of oxylipins were different for participants of lower socioeconomic status or of a systematically marginalized racial and ethnic groups. Given associations differed along biosynthetic pathways, results provide insight into etiologic links between maternal predictors and inflammation and oxidative stress.

Analysis of Vaginal Microbiota Variations in the Third Trimester of Pregnancy and Their Correlation with Preterm Birth: A Case-Control Study

This study conducted a detailed analysis of the vaginal microbiota in pregnant women to explore its correlation with preterm birth (PTB) outcomes. The primary objective was to identify microbial variations associated with increased PTB risk. Secondary objectives included investigating how changes in microbial composition relate to the local immune environment and PTB. Utilizing a retrospective case-control design, the study involved pregnant women with liveborn infants between 2019 and 2023. In total, 89 women who delivered preterm and 106 term deliveries were included. Data collection focused on third-trimester vaginal cultures. Statistically significant differences were observed between the preterm and full-term groups in several areas. The median white blood cell count (10.2 × 103/mm3 vs. 7.6 × 103/mm3, p = 0.009) and neutrophil count (7.2 × 103/mm3 vs. 5.1 × 103/mm3, p < 0.001) were higher in the preterm group. Vaginal pH was also elevated in preterm births (5.6 vs. 4.4, p < 0.001), with a higher prevalence of bacterial vaginosis (29.2% vs. 12.3%, p = 0.001) as indicated by the Nugent Score. The study noted a significant association of PTB with the presence of Candida spp. (OR = 1.84, p = 0.018), Gardnerella vaginalis (OR = 2.29, p = 0.003), Mycoplasma hominis (OR = 1.97, p = 0.007), and Ureaplasma urealyticum (OR = 2.43, p = 0.001). Conversely, a reduction in Lactobacillus spp. correlated with a decreased PTB risk (OR = 0.46, p = 0.001). The study provides compelling evidence that specific vaginal microbiota components, particularly certain pathogenic bacteria and an altered Lactobacillus profile, are significantly associated with PTB risk. These findings highlight the potential of targeting microbial factors in strategies aimed at reducing PTB rates. Further research is necessary to fully understand the complex interplay between microbial dynamics, host immunity, and PTB outcomes.

Recent Advances and Challenges in the Early Diagnosis and Treatment of Preterm Labor

Preterm birth (PTB) is the primary cause of neonatal mortality and long-term disabilities. The unknown mechanism behind PTB makes diagnosis difficult, yet early detection is necessary for controlling and averting related consequences. The primary focus of this work is to provide an overview of the known risk factors associated with preterm labor and the conventional and advanced procedures for early detection of PTB, including multi-omics and artificial intelligence/machine learning (AI/ML)- based approaches. It also discusses the principles of detecting various proteomic biomarkers based on lateral flow immunoassay and microfluidic chips, along with the commercially available point-of-care testing (POCT) devices and associated challenges. After briefing the therapeutic and preventive measures of PTB, this review summarizes with an outlook.

Associations of maternal inflammatory states with human milk composition in mothers of preterm infants

Introduction

Overweight/obesity (ow/ob) is increasing in prevalence in pregnant women, and it is associated with other pro-inflammatory states, such as pre-eclampsia, gestational diabetes, and preterm labor. Data are lacking if mothers experiencing inflammatory states who deliver preterm have mother's own milk (MOM) with differing inflammatory markers or pro-inflammatory fatty acid (FA) profiles.

Methods

The aim was to explore associations of maternal pre- and perinatal inflammatory states with levels of inflammatory markers and/or FAs in longitudinal samples of MOM from mothers of preterm infants born <1,250 g. Inflammatory states included pre-pregnancy ow/ob, diabetes, chorioamnionitis (chorio), preterm labor (PTL), premature rupture of membranes (PROM), pre-eclampsia, and cesarian delivery. In MOM, inflammatory markers studied included c-reactive protein (CRP), free choline, IFN-Ɣ, IL-10, IL-1β, IL-1ra, IL-6, IL-8, and TNF-α, and FAs included omega-6:omega-3 ratio, arachidonic acid, docosahexaenoic acid, linoleic acid, monounsaturated FAs, and saturated FAs. The above inflammatory states were assessed individually, and the healthiest mothers (normal BMI, no chorio, and ± no pre-eclampsia) were grouped. Regression analysis tested associations at baseline (day 5) and over time using generalized estimating equations.

Results

A total of 92 infants were included who were delivered to mothers (42% ow/ob) at a median gestational age of 27.7 weeks and birth weight of 850 g. MOM CRP was 116% higher (relative change 2.16) in mothers with ow/ob at baseline than others (p = 0.01), and lower (relative change 0.46, 0.33, respectively) in mothers in the two "healthy groups" at baseline (both p < 0.05) than others. MOM IL-8 levels were lower with chorio and PTL at baseline. No significant associations were found for other individual or grouped inflammatory states nor for other MOM inflammatory markers nor FA profiles at baseline.

Discussion

In conclusion, MOM CRP levels are positively associated with inflammatory states, such as ow/ob. Reassuringly, there was no association between FA profiles or most other inflammatory markers and maternal inflammatory states. Further studies are needed to determine potential associations or ramifications of MOM CRP in vulnerable preterm infants.

Antisecretory factor in breastmilk is associated with reduced incidence of sepsis in preterm infants

BACKGROUND

Antisecretory Factor (AF) is a protein present in breastmilk that regulates inflammatory processes. We aimed to investigate the level of AF in mothers' own milk (MOM) in relation to sepsis and other neonatal morbidities in preterm infants.

METHODS

Samples of breastmilk and infant plasma were collected at 1, 4, and 12 weeks after birth from 38 mothers and their 49 infants born before 30 weeks gestation. AF-compleasome in MOM was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) and inflammatory markers in infant plasma by a panel of 92 inflammatory proteins. Neonatal treatments and outcomes were recorded.

RESULTS

The level of AF in MOM week 1 was lower for infants with later sepsis compared to no sepsis (p = 0.005). Corrected for nutritional intake of MOM, higher levels of AF decreased the risk for sepsis, OR 0.24. AF in MOM week 1 was negatively correlated to inflammatory proteins in infant plasma week 4, markedly IL-8, which was also associated with infant sepsis. Overall, higher AF levels in MOM was associated with fewer major morbidities of prematurity.

CONCLUSION

Mother's milk containing high levels of antisecretory factor is associated with reduced risk for sepsis and inflammation in preterm infants.

IMPACT

High level of antisecretory factor (AF) in mothers' own milk is associated with less risk for later sepsis in preterm infants. Receiving mothers' milk with low AF levels during the first week after birth is correlated with more inflammatory proteins in infant's plasma 2-4 weeks later. Human breastmilk has anti-inflammatory properties, and antisecretory factor in mothers' own milk is a component of potential importance for infants born preterm. The findings suggest that food supplementation with AF to mothers of preterm infants to increase AF-levels in breastmilk may be a means to decrease the risk of inflammatory morbidities of prematurity.

Associations between gestational weight gain under different guidelines and adverse birth outcomes: A secondary analysis of a randomized controlled trial in rural western China

Several gestational weight gain (GWG) guidelines have been established based on monocenter or multicenter researches. We aimed to examine the associations between categories of GWG under the Institute of Medicine (IOM) recommendation guideline, the Chinese National Health Commission (NHC) guideline, and weight-gain-for-gestational-age z-scores derived from the INTERGROWTH-21st Project and adverse birth outcomes. We used data from an antenatal micronutrient supplementation trial in rural western China between 2002 and 2006. Maternal weekly average GWG during the second and third trimesters was calculated and classified into inadequate, adequate and excessive GWG according to the IOM and NHC, respectively. Weight-gain-for-gestational-age z-scores derived from the INTERGROWTH-21st Project were grouped into three subgroups using two approaches: z-score percentile<25th, 25th to 75th, >75th and z-score <-1, -1 to 1, >1 SD. Infant birth weight and gestational age were measured using standard approaches. Generalized linear model with binomial family and logit link was applied to estimate the odds ratio (OR) and 95% confidential intervals (CI) for GWG categories and adverse birth outcomes. Among 1,239 women with normal weight (18.5 kg/m2 to 23.9 kg/m2) during early pregnancy, 18.0% and 34.2% were classified as adequate GWG according to IOM and NHC, respectively. Less than half of Chinese women reached optimal GWG by any recommendation guideline. According to NHC, excessive GWG showed a significant association with macrosomia (OR 3.75, 95% CI 1.03, 13.74), large-for-gestation-age (LGA) (OR 2.12, 95% CI 1.01, 4.45), and inadequate GWG was associated with post-term birth (OR 2.25, 95% CI 1.21, 4.16), compared with adequate GWG. Inappropriate GWG was associated with adverse birth outcomes even among women with normal weight during early pregnancy. The monitoring and interventions of weight status during pregnancy, especially for the second and third trimesters, are of great public health importance for optimal birth outcomes. Additionally, developing guideline of appropriate GWG ranges should account for the traits of regional population.

Predictive and Diagnostic Values of Systemic Inflammatory Indices in Bronchopulmonary Dysplasia

BACKGROUND

Bronchopulmonary dysplasia (BPD) is the most common respiratory complication in preterm infants, and there is a lag in the diagnosis of BPD. Inflammation is a vital pathogenic factor for BPD; we aim to evaluate the predictive and diagnostic values of systemic inflammatory indices in BPD.

METHODS

Between 1 January 2019 and 31 May 2023, the clinical data of 122 premature infants with a gestational age of <32 weeks in the Department of Neonatology, the Affiliated Huai'an No. 1 People's Hospital of Nanjing Medical University, were retrospectively collected and classified into non-BPD (n = 72) and BPD (n = 50) groups based on the National Institute of Child Health and Human Development 2018 criteria. To compare the general characteristics of each group, we identified the independent risk variables for BPD using multivariate logistic regression analysis, compared the systemic inflammatory indices at birth, 72 h, 1 week, 2 weeks, and 36 weeks postmenstrual age (PMA), and constructed the receiver operating characteristic curves of neutrophil-to-lymphocyte ratio (NLR) diagnosis of BPD at different time points.

RESULTS

① The independent risk factors for BPD in preterm infants were birth weight, small for gestational age, and days of oxygen therapy (all p < 0.05). ② At 72 h and 1 week after birth, the serum NLR of the BPD group was higher than for the non-BPD group (p < 0.05). Furthermore, the neutrophil count (N), NLR, monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index, systemic inflammation response index (SIRI), and pan-immune-inflammation value of infants with BPD were higher than the non-BPD group at 3 weeks after birth (p < 0.05). Moreover, at 36 weeks of PMA, the serum N, NLR, MLR, and SIRI of BPD infants were higher than those of non-BPD infants (p < 0.05). ③ The NLR of infants with and without BPD gradually increased after birth, reaching a peak at 72 h and 1 week, respectively. At 3 weeks postnatal, the NLR had the highest predictive power for BPD, with an area under the curve (AUC) of 0.717 (p < 0.001); the sensitivity was 56% and specificity was 86.1%. In addition, the NLR at 36 weeks of PMA exhibited some diagnostic value for BPD. The AUC was 0.693 (p < 0.001), the sensitivity was 54%, and specificity was 83.3%.

CONCLUSIONS

At 3 weeks after birth and 36 weeks of PMA, some systemic inflammation indices (like N, NLR, SIRI) of preterm infants with BPD have specific predictive and diagnostic values; these indices may help the management of high-risk preterm infants with BPD.

Overnutrition during Pregnancy and Lactation Induces Gender-Dependent Dysmetabolism in the Offspring Accompanied by Heightened Stress and Anxiety

Maternal obesity and gestational diabetes predispose the next generation to metabolic disturbances. Moreover, the lactation phase also stands as a critical phase for metabolic programming. Nevertheless, the precise mechanisms originating these changes remain unclear. Here, we investigate the consequences of a maternal lipid-rich diet during gestation and lactation and its impact on metabolism and behavior in the offspring. Two experimental groups of Wistar female rats were used: a control group (NC) that was fed a standard diet during the gestation and lactation periods and an overnutrition group that was fed a high-fat diet (HF, 60% lipid-rich) during the same phases. The offspring were analyzed at postnatal days 21 and 28 and at 2 months old (PD21, PD28, and PD60) for their metabolic profiles (weight, fasting glycemia insulin sensitivity, and glucose tolerance) and euthanized for brain collection to evaluate metabolism and inflammation in the hypothalamus, hippocampus, and prefrontal cortex using Western blot markers of synaptic dynamics. At 2 months old, behavioral tests for anxiety, stress, cognition, and food habits were conducted. We observed that the female offspring born from HF mothers exhibited increased weight gain and decreased glucose tolerance that attenuated with age. In the offspring males, weight gain increased at P21 and worsened with age, while glucose tolerance remained unchanged. The offspring of the HF mothers exhibited elevated levels of anxiety and stress during behavioral tests, displaying decreased predisposition for curiosity compared to the NC group. In addition, the offspring from mothers with HF showed increased food consumption and a lower tendency towards food-related aggression. We conclude that exposure to an HF diet during pregnancy and lactation induces dysmetabolism in the offspring and is accompanied by heightened stress and anxiety. There was sexual dimorphism in the metabolic traits but not behavioral phenotypes.

Histologic chorioamnionitis in extremely preterm births, microbiological findings and infant outcome

BACKGROUND

Histologic chorioamnionitis (HCA) is most often caused by ascending bacterial infection originating from the cervicovaginal tract.

OBJECTIVES

To investigate whether HCA with a fetal inflammatory response (FIR) has a worse clinical outcome than HCA alone. Further, if FIR or a positive maternal microbiologic culture obtained prior to birth were related to adverse neonatal outcomes in a cohort of extremely preterm (EP) neonates.

METHODS

Prospective observational cohort study recruiting EP singleton pregnancies (gestational age at birth ≤28 weeks) with confirmed HCA. FIR was defined by fetal neutrophils in the chorionic vessels and/or umbilical vessels. Positive culture was defined as growth of potentially pathogenic bacteria in a sample from the cervicovaginal tract prior to birth, or if a cervicovaginal culture was lacking, a culture result from the placenta was used. Logistic regression was used to estimate odds ratios and 95% confidence intervals for the associations between FIR, a positive culture result and adverse outcomes, defined as bronchopulmonary dysplasia (BPD), brain pathology assessed by magnetic resonance imaging, retinopathy of prematurity, necrotizing enterocolitis, early-onset neonatal sepsis, and perinatal death. A composite outcome variable included one or more adverse outcomes.

RESULTS

We included 71 cases with HCA, of which 51 (72%) had FIR. Maternal age, rate of clinical chorioamnionitis (CCA), preterm pre-labor rupture of membranes (PPROM), the number of women receiving antenatal steroids and antibiotics, and the rate of positive maternal cultures of potentially pathogenic bacteria were all significantly higher in the HCA with FIR. Neonates in the FIR group had significantly higher levels of blood leukocytes compared to those without. FIR was associated with a longer interval from PPROM to delivery (log-rank test: p = .022). Microbiological sampling had been performed in 63 (89%) cases, of which 60 (95%) were cervicovaginal samples. No associations were found between a positive culture and adverse neonatal outcomes, in contrast to FIR, that was significantly associated to BPD and brain pathology.

CONCLUSIONS

In a cohort of EP pregnancies with confirmed HCA, the presence of FIR was associated with advanced maternal age, CCA, PPROM, antenatal steroids and antibiotics, and a positive maternal culture of potentially pathogenic bacteria. However, the presence of FIR, and not a positive culture, was associated with adverse neonatal outcomes.

Leveraging transcriptomics to develop bronchopulmonary dysplasia endotypes: a concept paper

IMPACT

Bronchopulmonary dysplasia has multiple definitions that are currently based on phenotypic characteristics. Using an unsupervised machine learning approach, we created BPD subclasses (e.g., endotypes) by clustering whole microarray data. T helper 17 cell differentiation was the most significant pathway differentiating the BPD endotypes.

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is the most common complication of extreme prematurity. Discovery of BPD endotypes in an unbiased format, derived from the peripheral blood transcriptome, may uncover patterns underpinning this complex lung disease.

METHODS

An unsupervised agglomerative hierarchical clustering approach applied to genome-wide expression of profiling from 62 children at day of life five was used to identify BPD endotypes. To identify which genes were differentially expressed across the BPD endotypes, we formulated a linear model based on least-squares minimization with empirical Bayes statistics.

RESULTS

Four BPD endotypes (A, B,C,D) were identified using 7,319 differentially expressed genes. Across BPD endotypes, 5,850 genes had a p value < 0.05 after multiple comparison testing. Endotype A consisted of neonates with a higher gestational age and birthweight. Endotypes B-D included neonates between 25 and 26 weeks and a birthweight range of 640 to 940 g. Endotype D appeared to have a protective role against BPD compared to Endotypes B and C (36% vs. 62% vs. 60%, respectively). The most significant pathway focused on T helper 17 cell differentiation.

CONCLUSION

Bioinformatic analyses can help identify BPD endotypes that associate with clinical definitions of BPD.

Inflammation and Oxidative Stress Induced by Obesity, Gestational Diabetes, and Preeclampsia in Pregnancy: Role of High-Density Lipoproteins as Vectors for Bioactive Compounds

Inflammation and oxidative stress are essential components in a myriad of pathogenic entities that lead to metabolic and chronic diseases. Moreover, inflammation in its different phases is necessary for the initiation and maintenance of a healthy pregnancy. Therefore, an equilibrium between a necessary/pathologic level of inflammation and oxidative stress during pregnancy is needed to avoid disease development. High-density lipoproteins (HDL) are important for a healthy pregnancy and a good neonatal outcome. Their role in fetal development during challenging situations is vital for maintaining the equilibrium. However, in certain conditions, such as obesity, diabetes, and other cardiovascular diseases, it has been observed that HDL loses its protective properties, becoming dysfunctional. Bioactive compounds have been widely studied as mediators of inflammation and oxidative stress in different diseases, but their mechanisms of action are still unknown. Nonetheless, these agents, which are obtained from functional foods, increase the concentration of HDL, TRC, and antioxidant activity. Therefore, this review first summarizes several mechanisms of HDL participation in the equilibrium between inflammation and oxidative stress. Second, it gives an insight into how HDL may act as a vector for bioactive compounds. Third, it describes the relationships between the inflammation process in pregnancy and HDL activity. Consequently, different databases were used, including MEDLINE, PubMed, and Scopus, where scientific articles published in the English language up to 2023 were identified.

Accelerated Aging and the Life Course of Individuals Born Preterm

Individuals born preterm have shorter lifespans and elevated rates of chronic illness that contribute to mortality risk when compared to individuals born at term. Emerging evidence suggests that individuals born preterm or of low birthweight also exhibit physiologic and cellular biomarkers of accelerated aging. It is unclear whether, and to what extent, accelerated aging contributes to a higher risk of chronic illness and mortality among individuals born preterm. Here, we review accelerated aging phenotypes in adults born preterm and biological pathways that appear to contribute to accelerated aging. We highlight biomarkers of accelerated aging and various resiliency factors, including both pharmacologic and non-pharmacologic factors, that might buffer the propensity for accelerated aging among individuals born preterm.

Risk Factors for Dehiscence of Operative Incisions in Newborns after Laparotomy

BACKGROUND

 Surgical wound dehiscence (SWD) in neonates is a life-threatening complication. The aim was to define risk factors of postoperative incision dehiscence in this population.

METHODS

 Data of 144 patients from 2010 to 2020 were analyzed retrospectively. All full-term newborns or preterm newborns up to 42 weeks of amenorrhea (adjusted) who had a laparotomy within 30 days were included. Descriptive patient information and perioperative data were collected. SWD was defined as any separation of cutaneous edges of postoperative wounds.

RESULTS

 Overall, SWD occurred in 16/144 (11%) patients, with a significantly increased incidence in preterm newborns (13/59, 22%) compared with full-term newborns (3/85, 4%; p < 0.001). SWD was significantly associated with exposure to postnatal steroids (60% vs. 4%, p < 0.001) and nonsteroidal anti-inflammatory drugs (25% vs. 4%, p < 0.01), invasive ventilation duration before surgery (median at 10 vs. 0 days, p < 0.001), preoperative low hemoglobin concentration (115 vs. 147 g/L, p < 0.001) and platelet counts (127 vs. 295 G/L, p < 0.001), nonabsorbable suture material (43% vs. 8%, p < 0.001), the presence of ostomies (69% vs. 18%, p < 0.001), positive bacteriological wound cultures (50% vs. 6%, p < 0.001), and relaparotomy (25% vs. 3%, p < 0.01). Thirteen of 16 patients with SWD presented necrotizing enterocolitis/intestinal perforations (81%, p < 0.001).

CONCLUSION

 This study identified prematurity and a number of other factors linked to the child's general condition as risk factors for SWD. Some of these can help physicians recognize and respond to at-risk patients and provide better counseling for parents.

Prognostic accuracy of Neonatal SOFA score versus SIRS criteria in preterm infants with late-onset sepsis

Neonatal SOFA score was reported as an accurate predictor of mortality while the prognostic accuracy of SIRS criteria is unknown. The aim was to compare neonatal SOFA and SIRS criteria for the prediction of late onset sepsis-related mortality in preterm newborns. Newborns ≤ 32 weeks with late onset sepsis were retrospectively studied. Neonatal SOFA and SIRS criteria were calculated at onset of sepsis (T0), and after 6 ± 1 (T1), 12 ± 3 (T2) and 24 ± 3 h (T3). Outcome was death during antibiotic treatment for late onset sepsis. We studied 112 newborns with gestational age 26.9 ± 2.3 weeks; 11% met the study outcome. Neonatal SOFA was significantly higher in non-survivors vs. survivors at all time intervals; SIRS criteria were significantly higher in non-survivors vs. survivors at T1, T2 and T3. Neonatal SOFA increased over time in non-survivors (p = 0.003). At T0, the area under receiver operating characteristics curve was significantly higher for neonatal SOFA score than SIRS criteria (0.950 vs. 0.569; p = 0.0002), and the best calculated cut-off for T0 neonatal SOFA score was 4. In multivariate analysis T0 and T1 neonatal SOFA were predictors of late onset sepsis-related mortality (p = 0.048 and p < 0.001).  Conclusion: Neonatal SOFA score showed greater discriminatory capacity for mortality than SIRS criteria and might be helpful to plan management for patients at higher risk of death. What is Known: • Neonatal SOFA score may be an accurate prognostic tool. • No prognostic score has been fully standardized for septic newborns in NICU. What is New: • Neonatal SOFA score outperformed SIRS criteria for the prediction of prognosis in preterm infants with late onset sepsis. • Neonatal SOFA score assessed at onset of sepsis and 6 hrs later is a predictor of mortality.

Consequences of Preterm Birth: Knowns, Unknowns, and Barriers to Advancing Cardiopulmonary Health

Preterm birth occurs in 10% of all live births and creates challenges to neonatal life, which persist into adulthood. Significant previous work has been undertaken to characterize and understand the respiratory and cardiovascular sequelae of preterm birth, which are present in adulthood, i.e., "late" outcomes. However, many gaps in knowledge are still present and there are several challenges that will make filling these gaps difficult. In this perspective we discuss the obstacles of studying adults born preterm, including (1) the need for invasive (direct) measures of physiologic function; (2) the need for multistate, multinational, and diverse cohorts; (3) lack of socialized medicine in the United States; (4) need for detailed and better-organized birth records; and (5) transfer of neonatal and pediatric knowledge to adult care physicians. We conclude with a discussion on the "future" of studying preterm birth in regards to what may happen to these individuals as they approach middle and older age and how the improvements in perinatal and postnatal care may be changing the phenotypes observed in adults born preterm on or after the year 2000.

Late-onset sepsis in very preterm infants in Norway in 2009-2018: a population-based study

OBJECTIVE

To evaluate epidemiology and outcomes among very preterm infants (<32 weeks' gestation) with culture-positive and culture-negative late-onset sepsis (LOS).

DESIGN

Cohort study using a nationwide, population-based registry.

SETTING

21 neonatal units in Norway.

PARTICIPANTS

All very preterm infants born 1 January 2009-31 December 2018 and admitted to a neonatal unit.

MAIN OUTCOME MEASURES

Incidences, pathogen distribution, LOS-attributable mortality and associated morbidity at discharge.

RESULTS

Among 5296 very preterm infants, we identified 582 culture-positive LOS episodes in 493 infants (incidence 9.3%) and 282 culture-negative LOS episodes in 282 infants (incidence 5.3%). Extremely preterm infants (<28 weeks' gestation) had highest incidences of culture-positive (21.6%) and culture-negative (11.1%) LOS. The major causative pathogens were coagulase-negative staphylococci (49%), Staphylococcus aureus (15%), group B streptococci (10%) and Escherichia coli (8%). We observed increased odds of severe bronchopulmonary dysplasia (BPD) associated with both culture-positive (adjusted OR (aOR) 1.7; 95% CI 1.3 to 2.2) and culture-negative (aOR 1.6; 95% CI 1.3 to 2.6) LOS. Only culture-positive LOS was associated with increased odds of cystic periventricular leukomalacia (cPVL) (aOR 2.2; 95% CI 1.4 to 3.4) and severe retinopathy of prematurity (ROP) (aOR 1.8; 95% CI 1.2 to 2.8). Culture-positive LOS-attributable mortality was 6.3%, higher in Gram-negative (15.8%) compared with Gram-positive (4.1%) LOS, p=0.009. Among extremely preterm infants, survival rates increased from 75.2% in 2009-2013 to 81.0% in 2014-2018, p=0.005. In the same period culture-positive LOS rates increased from 17.1% to 25.6%, p<0.001.

CONCLUSIONS

LOS contributes to a significant burden of disease in very preterm infants and is associated with increased odds of severe BPD, cPVL and severe ROP.

Role of the gut-microbiota-metabolite-brain axis in the pathogenesis of preterm brain injury

Brain injury, a common complication in preterm infants, includes the destruction of the key structural and functional connections of the brain and causes neurodevelopmental disorders; it has high morbidity and mortality rates. The exact mechanism underlying brain injury in preterm infants is unclear. Intestinal flora plays a vital role in brain development and the maturation of the immune system in infants; however, detailed understanding of the gut microbiota-metabolite-brain axis in preterm infants is lacking. In this review, we summarise the key mechanisms by which the intestinal microbiota contribute to neurodevelopment and brain injury in preterm infants, with special emphasis on the influence of microorganisms and their metabolites on the regulation of neurocognitive development and neurodevelopmental risks related to preterm birth, infection and neonatal necrotising enterocolitis (NEC). This review provides support for the development and application of novel therapeutic strategies, including probiotics, prebiotics, synbiotics, and faecal bacteria transplantation targeting at brain injury in preterm infants.

Melatonin as a Therapy for Preterm Brain Injury: What Is the Evidence?

Despite significant improvements in survival following preterm birth in recent years, the neurodevelopmental burden of prematurity, with its long-term cognitive and behavioral consequences, remains a significant challenge in neonatology. Neuroprotective treatment options to improve neurodevelopmental outcomes in preterm infants are therefore urgently needed. Alleviating inflammatory and oxidative stress (OS), melatonin might modify important triggers of preterm brain injury, a complex combination of destructive and developmental abnormalities termed encephalopathy of prematurity (EoP). Preliminary data also suggests that melatonin has a direct neurotrophic impact, emphasizing its therapeutic potential with a favorable safety profile in the preterm setting. The current review outlines the most important pathomechanisms underlying preterm brain injury and correlates them with melatonin's neuroprotective potential, while underlining significant pharmacokinetic/pharmacodynamic uncertainties that need to be addressed in future studies.

The Association Between Immune-Related Conditions Across the Life-Course and Provoked Vulvodynia

Vulvodynia, impacts up to 8% of women by age 40, and is hypothesized to manifest through an altered immune-inflammatory response. To test this hypothesis, we identified all women born in Sweden between 1973 and 1996 diagnosed with localized provoked vulvodynia (N76.3) and/or vaginismus (N94.2 or F52.5) between 2001 and 2018. We matched each case to two women from the same birth year with no vulvar pain ICD codes. As a proxy for immune dysfunction, we used Swedish Registry data to capture 1) immunodeficiencies, 2) single organ and multiorgan autoimmune conditions, 3) allergy and atopies, and 4) malignancies involving immune cells across the life course. Women with vulvodynia, vaginismus or both were more likely to experience immune deficiencies (OR 1.8, 95% CI, 1.2-2.8), single organ (OR 1.4, 95% CI, 1.2-1.6) and/or multi-organ (OR 1.6, 95% CI, 1.3-1.9) immune disorders, and allergy/atopy conditions (OR 1.7, 95% CI, 1.6-1.8) compared to controls. We observed greater risk with increasing numbers of unique immune related conditions (1 code: OR = 1.6, 95% CI, 1.5-1.7; 2 codes: OR = 2.4, 95% CI, 2.1-2.9; 3 or more codes: OR = 2.9, 1.6-5.4). These findings suggest that women with vulvodynia may have a more compromised immune system either at birth or at points across the life course than women with no vulvar pain history. PERSPECTIVE: Women with vulvodynia are substantially more likely to experience a spectrum of immune related conditions across the life course. These findings lend support to the hypothesis that chronic inflammation initiates the hyperinnervation that causes the debilitating pain in women with vulvodynia.

Preterm-born individuals: a vulnerable population at risk of cardiovascular morbidity and mortality during thermal extremes?

NEW FINDINGS

What is the topic of this review? Thermal extremes disproportionately affect populations with cardiovascular conditions. Preterm birth, across all gestational age ranges below 37 weeks, has been identified as a non-modifiable risk factor for cardiovascular disease. The hypothesis is presented that individuals born preterm are at an increased risk of cardiovascular morbidity and mortality during thermal extremes. What advances does it highlight? Cardiovascular stress tests performed in preterm-born populations, from infancy through adulthood, highlight a progression of cardiovascular dysfunction accelerating through adolescence and adulthood. This dysfunction has many similarities with populations known to be at risk in thermal extremes.

ABSTRACT

Preterm-born individuals are a uniquely vulnerable population. Preterm exposure to the extrauterine environment and the (mal)adaptations that occur during the transitional period can result in alterations to their macro- and micro-physiological state. The physiological adaptations that increase survival in the short term may place those born preterm on a trajectory of lifelong dysfunction and later-life decompensation. Cardiovascular compensation in children and adolescents, which masks this trajectory of dysfunction, is overcome under stress, such that the functional cardiovascular capacity is reduced and recovery impaired following physiological stress. This has implications for their response to thermal stress. As the Anthropocene introduces greater changes in our environment, thermal extremes will impact vulnerable populations as yet unidentified in the climate change context. Here, we present the hypothesis that individuals born preterm are a vulnerable population at an increased risk of cardiovascular morbidity and mortality during thermal extremes.

Proteomics identifies lipocalin-2 in neonatal inflammation associated with cerebrovascular alteration in mice and preterm infants

Staphylococcus (S.) epidermidis is the most common nosocomial coagulase-negative staphylococci infection in preterm infants. Clinical signs of infection are often unspecific and novel markers to complement diagnosis are needed. We investigated proteomic alterations in mouse brain after S. epidermidis infection and in preterm infant blood. We identified lipocalin-2 (LCN2) as a crucial protein associated with cerebrovascular changes and astrocyte reactivity in mice. We further proved that LCN2 protein expression was associated with endothelial cells but not astrocyte reactivity. By combining network analysis and differential expression approaches, we identified LCN2 linked to blood C-reactive protein levels in preterm infants born <28 weeks of gestation. Blood LCN2 levels were associated with similar alterations of cytokines and chemokines in both infected mice and human preterm infants with increased levels of C-reactive protein. This experimental and clinical study suggests that LCN2 may be a marker of preterm infection/inflammation associated with cerebrovascular changes and neuroinflammation.

Determinants of microbial colonization in the premature gut

Abnormal microbial colonization in the gut at an early stage of life affects growth, development, and health, resulting in short- and long-term adverse effects. Microbial colonization patterns of preterm infants differ from those of full-term infants in that preterm babies and their mothers have more complicated prenatal and postnatal medical conditions. Maternal complications, antibiotic exposure, delivery mode, feeding type, and the use of probiotics may significantly shape the gut microbiota of preterm infants at an early stage of life; however, these influences subside with age. Although some factors and processes are difficult to intervene in or avoid, understanding the potential factors and determinants will help in developing timely strategies for a healthy gut microbiota in preterm infants. This review discusses potential determinants of gut microbial colonization in preterm infants and their underlying mechanisms.

Association between prenatal socioeconomic disadvantage, adverse birth outcomes, and inflammatory response at birth

Prenatal socioeconomic disadvantage is associated with inflammation in mid- to late-life, yet whether a pro-inflammatory phenotype is present at birth and the role of adverse birth outcomes in this pathway remains unclear. We utilized data on prenatal socioeconomic disadvantage at the individual- (i.e., mother's and father's education level, insurance type, marital status, and Women, Infants, and Children benefit receipt) and census-tract level as well as preterm (< 37 weeks gestation) and small-for-gestational-age (SGA) (i.e., < 10th percentile of sex-specific birth weight for gestational age) birth status, and assessed inflammatory markers (i.e., C-reactive protein, serum amyloid p, haptoglobin, and α-2 macroglobulin) in archived neonatal bloodspots from a Michigan population-based cohort of 1000 neonates. Continuous latent variables measuring individual- and combined individual- and neighborhood-level prenatal socioeconomic disadvantage were constructed and latent profile analysis was used to create a categorical inflammatory response variable (high versus low) based on continuous inflammatory marker levels. Structural equation models were used to estimate the total and direct effect of prenatal socioeconomic disadvantage on the inflammatory response at birth as well as indirect effect via preterm or SGA birth (among term neonates only), adjusting for mother's age, race/ethnicity, body mass index, smoking status, comorbidities, and antibiotic use/infection as well as grandmother's education level. There was a statistically significant total effect of both individual- and combined individual- and neighborhood-level prenatal socioeconomic disadvantage on high inflammatory response among all neonates as well as among term neonates only, and a positive but not statistically significant direct effect in both groups. The indirect effects via preterm and SGA birth were both negative, but not statistically significant. Our findings suggest prenatal socioeconomic disadvantage contributes to elevated neonatal inflammatory response, but via pathways outside of these adverse birth outcomes.

Interrogating Components of 2 Diet Quality Indices in Pregnancy using a Supervised Statistical Mixtures Approach

BACKGROUND

The Healthy Eating Index (HEI)-2015 and Alternative Healthy Eating Index (AHEI)-2010 evaluate diet holistically in pregnancy. However, it remains unclear how individual index components interact to contribute to health.

OBJECTIVES

To evaluate associations of HEI-2015 and AHEI-2010 components with gestational length using traditional and novel statistical methods in a prospective cohort.

METHODS

Pregnant women completed a 3-mo food-frequency questionnaire (FFQ) at median 13 wk gestation to calculate the HEI-2015 or AHEI-2010. Covariate-adjusted linear regression models evaluated associations of HEI-2015 and AHEI-2010 total scores and individual components (one at a time and simultaneously adjusted) with gestational length. Covariate-adjusted weighted quantile sum regression models evaluated 1) associations of HEI-2015 or AHEI-2010 components as mixtures with gestational length and 2) contributions of components to these associations.

RESULTS

Each 10-point increase in HEI-2015 and AHEI-2010 total score was associated with 0.11 (95% CI: -0.05, 0.27) and 0.14 (95% CI: 0.00, 0.28) wk longer gestation, respectively. In individual or simultaneously adjusted HEI-2015 models, higher intakes of seafood/plant proteins, total protein foods, greens/beans, and saturated fats but lower intakes of added sugars and refined grains were associated with longer gestational length. For the AHEI-2010, higher intake of nuts/legumes and lower intake of sugar-sweetened beverages (SSBs)/fruit juice were associated with longer gestational length. Jointly, 10% increases in HEI-2015 or AHEI-2010 mixtures were associated with 0.17 (95% CI: 0.001, 0.34) and 0.18 (95% CI: 0.05, 0.30) wk longer gestational length, respectively. Seafood/plant protein, total protein foods, dairy, greens/beans, and added sugars were the largest contributors to the HEI-2015 mixture. Nuts/legumes, SSBs/fruit juice, sodium, and DHA/EPA were the largest contributors to the AHEI-2010 mixture. Associations were less precise but consistent in women with spontaneous labors.

CONCLUSIONS

Compared to traditional methods, associations of diet index mixtures with gestational length were more robust and identified unique contributors. Additional studies could consider interrogating these statistical approaches using other dietary indices and health outcomes.

Increased Expression of Anaphylatoxin C5a-Receptor-1 in Neutrophils and Natural Killer Cells of Preterm Infants

Preterm infants are susceptible to infection and their defense against pathogens relies largely on innate immunity. The role of the complement system for the immunological vulnerability of preterm infants is less understood. Anaphylatoxin C5a and its receptors C5aR1 and -2 are known to be involved in sepsis pathogenesis, with C5aR1 mainly exerting pro-inflammatory effects. Our explorative study aimed to determine age-dependent changes in the expression of C5aR1 and C5aR2 in neonatal immune cell subsets. Via flow cytometry, we analyzed the expression pattern of C5a receptors on immune cells isolated from peripheral blood of preterm infants (n = 32) compared to those of their mothers (n = 25). Term infants and healthy adults served as controls. Preterm infants had a higher intracellular expression of C5aR1 on neutrophils than control individuals. We also found a higher expression of C5aR1 on NK cells, particularly on the cytotoxic CD56^dim subset and the CD56^- subset. Immune phenotyping of other leukocyte subpopulations revealed no gestational-age-related differences for the expression of and C5aR2. Elevated expression of C5aR1 on neutrophils and NK cells in preterm infants may contribute to the phenomenon of "immunoparalysis" caused by complement activation or to sustained hyper-inflammatory states. Further functional analyses are needed to elucidate the underlying mechanisms.

A multi-omic approach identifies an autism spectrum disorder (ASD) regulatory complex of functional epimutations in placentas from children born preterm

Children born preterm are at heightened risk of neurodevelopmental impairments, including Autism Spectrum Disorder (ASD). The placenta is a key regulator of neurodevelopmental processes, though the precise underlying molecular mechanisms remain unclear. Here, we employed a multi-omic approach to identify placental transcriptomic and epigenetic modifications related to ASD diagnosis at age 10, among children born preterm. Working with the extremely low gestational age (ELGAN) cohort, we hypothesized that a pro-inflammatory placental environment would be predictive of ASD diagnosis at age 10. Placental messenger RNA (mRNA) expression, CpG methylation, and microRNA (miRNA) expression were compared among 368 ELGANs (28 children diagnosed with ASD and 340 children without ASD). A total of 111 genes displayed expression levels in the placenta that were associated with ASD. Within these ASD-associated genes is an ASD regulatory complex comprising key genes that predicted ASD case status. Genes with expression that predicted ASD case status included Ewing Sarcoma Breakpoint Region 1 (EWSR1) (OR: 6.57 (95% CI: 2.34, 23.58)) and Bromodomain Adjacent To Zinc Finger Domain 2A (BAZ2A) (OR: 0.12 (95% CI: 0.03, 0.35)). Moreover, of the 111 ASD-associated genes, nine (8.1%) displayed associations with CpG methylation levels, while 14 (12.6%) displayed associations with miRNA expression levels. Among these, LRR Binding FLII Interacting Protein 1 (LRRFIP1) was identified as being under the control of both CpG methylation and miRNAs, displaying an OR of 0.42 (95% CI: 0.17, 0.95). This gene, as well as others identified as having functional epimutations, plays a critical role in immune system regulation and inflammatory response. In summary, a multi-omic approach was used to identify functional epimutations in the placenta that are associated with the development of ASD in children born preterm, highlighting future avenues for intervention.

Immuno-epigenetic signature derived in saliva associates with the encephalopathy of prematurity and perinatal inflammatory disorders

BACKGROUND

Preterm birth is closely associated with a phenotype that includes brain dysmaturation and neurocognitive impairment, commonly termed Encephalopathy of Prematurity (EoP), of which systemic inflammation is considered a key driver. DNA methylation (DNAm) signatures of inflammation from peripheral blood associate with poor brain imaging outcomes in adult cohorts. However, the robustness of DNAm inflammatory scores in infancy, their relation to comorbidities of preterm birth characterised by inflammation, neonatal neuroimaging metrics of EoP, and saliva cross-tissue applicability are unknown.

METHODS

Using salivary DNAm from 258 neonates (n = 155 preterm, gestational age at birth 23.28 - 34.84 weeks, n = 103 term, gestational age at birth 37.00 - 42.14 weeks), we investigated the impact of a DNAm surrogate for C-reactive protein (DNAm CRP) on brain structure and other clinically defined inflammatory exposures. We assessed i) if DNAm CRP estimates varied between preterm infants at term equivalent age and term infants, ii) how DNAm CRP related to different types of inflammatory exposure (maternal, fetal and postnatal) and iii) whether elevated DNAm CRP associated with poorer measures of neonatal brain volume and white matter connectivity.

RESULTS

Higher DNAm CRP was linked to preterm status (-0.0107 ± 0.0008, compared with -0.0118 ± 0.0006 among term infants; p < 0.001), as well as perinatal inflammatory diseases, including histologic chorioamnionitis, sepsis, bronchopulmonary dysplasia, and necrotising enterocolitis (OR range |2.00 | to |4.71|, p < 0.01). Preterm infants with higher DNAm CRP scores had lower brain volume in deep grey matter, white matter, and hippocampi and amygdalae (β range |0.185| to |0.218|). No such associations were observed for term infants. Association magnitudes were largest for measures of white matter microstructure among preterms, where elevated epigenetic inflammation associated with poorer global measures of white matter integrity (β range |0.206| to |0.371|), independent of other confounding exposures.

CONCLUSIONS

Inflammatory-related DNAm captures the allostatic load of inflammatory burden in preterm infants. Such DNAm measures complement biological and clinical metrics when investigating the determinants of neurodevelopmental differences.

Essential Fatty Acid Supplementation and Early Inflammation in Preterm Infants: Secondary Analysis of a Randomized Clinical Trial

INTRODUCTION

Postnatal inflammation is associated with increased mortality and adverse outcomes in preterm infants. The essential fatty acids arachidonic acid (ARA) and docosahexaenoic acid (DHA) are precursors of lipid mediators with a key role in resolving inflammation. Our aim was to investigate the effect of ARA and DHA supplementation on systemic inflammation in very preterm infants and to identify clinical factors associated with early inflammation.

METHODS

Secondary analysis of data from a randomized clinical trial (ImNuT study). Infants with gestational age (GA) less than 29 weeks were randomized to receive a daily enteral supplement with ARA 100 mg/kg and DHA 50 mg/kg (ARA:DHA group) or MCT oil (control group) from the second day of life to 36 weeks postmenstrual age. ARA, DHA, and four proinflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α) were analyzed in repeated dried blood samples from birth to day 28 and the area under the curve (AUC) for each variable was calculated.

RESULTS

The intention to treat population included 120 infants with mean (SD) GA 26.4 (1.7). The ARA:DHA group had significantly lower IL-6 levels from day 3 to day 28 compared to the control group, mean difference AUC log10 (95% CI): 0.16 (0.03-0.30) pg/mL, p = 0.018. There was no correlation between ARA or DHA blood concentrations and cytokine levels. Having a low gestational age was independently associated with increased levels of all cytokines during the first 4 weeks of life.

CONCLUSIONS

Enhanced supplementation with ARA and DHA may modulate inflammation in very preterm infants.

Maternal and Neonatal Factors Modulating Breast Milk Cytokines in the First Month of Lactation

Breast milk (BM) cytokines support and modulate infant immunity, being particularly relevant in premature neonates with adverse outcomes (NAO). This study aimed to examine, in a cohort of Spanish breastfeeding women, changes in BM cytokines in the first month of lactation, their modulation by neonatal factors (sex, gestational age, and NAO), maternal factors (obstetric complications, C-section, and diet), and their relationship with oxidative status. Sixty-three mother-neonate dyads were studied at days 7 and 28 of lactation. Dietary habits were assessed by a 72-h dietary recall, and the maternal dietary inflammatory index (mDII) was calculated. BM cytokines (IL-10, IL-13, IL-8, MCP-1, and TNFα) were assessed by ultra-sensitive chemiluminescence. Total antioxidant capacity was assessed by the ABTS method and lipid peroxidation by the MDA+HNE kit. From days 7 to 28 of lactation, the levels of IL-10 and TNFα remained stable, while IL-13 increased (β = 0.85 ± 0.12, p < 0.001) and IL-8 and MCP-1 levels decreased (β = -0.64 ± 0.27, p = 0.019; β = -0.98 ± 0.22, p < 0.001; respectively). Antioxidant capacity and lipid peroxidation also decrease during lactation. Neonatal sex did not influence any of the cytokines, but BM from mothers with male infants had a higher antioxidant capacity. Gestational age was associated with male sex and NAO, being inversely correlated with the BM proinflammatory cytokines IL-8, MCP-1, and TNFα. From days 7 to 28 of lactation, BM from women with NAO infants increased MCP-1 levels and had a larger drop in antioxidant capacity, with the opposite trend in lipid peroxidation. MCP-1 was also significantly higher in women undergoing C-section; this cytokine declined in women who decreased mDII during lactation, while IL-10 increased. Linear mixed regression models evidenced that the most important factors modulating BM cytokines were lactation period and gestational age. In conclusion, during the first month of lactation, BM cytokines shift towards an anti-inflammatory profile, influenced mainly by prematurity. BM MCP-1 is associated with maternal and neonatal inflammatory processes.

SELENOP rs3877899 Variant Affects the Risk of Developing Advanced Stages of Retinopathy of Prematurity (ROP)

The significance of selenoproteins for the incidence of prematurity and oxidative-damage-related diseases in premature newborns is poorly understood. The latter are at risk for ROP as well as BPD, IVH, PDA, RDS, and NEC, which is particularly high for newborns with extremely low gestational age (ELGA) and extremely low birth weight (ELBW). This study evaluates the hypothesis that variation in the selenoprotein-encoding genes SELENOP, SELENOS, and GPX4 affects the risk of ROP and other comorbidities. The study included infants born ≤ 32 GA, matched for onset and progression of ROP into three groups: no ROP, spontaneously remitting ROP, and ROP requiring treatment. SNPs were determined with predesigned TaqMan SNP genotyping assays. We found the association of the SELENOP rs3877899A allele with ELGA (defined as <28 GA), ROP requiring treatment, and ROP not responsive to treatment. The number of RBC transfusions, ELGA, surfactant treatment, and coexistence of the rs3877899A allele with ELGA were independent predictors of ROP onset and progression, accounting for 43.1% of the risk variation. In conclusion, the SELENOP rs3877899A allele associated with reduced selenium bioavailability may contribute to the risk of ROP and visual impairment in extremely preterm infants.

Monocyte signature as a predictor of chronic lung disease in the preterm infant

Introduction

Inflammation is a key driver of morbidity in the vulnerable preterm infant exposed to pre- and postnatal hazards and significantly contributes to chronic lung disease, i.e. bronchopulmonary dysplasia (BPD). However, the early changes in innate immunity associated with BPD development are incompletely understood.

Methods

In very immature preterm infants below 32 weeks gestational age (GA; n=30 infants), monocyte subtypes were identified by Flow Cytometry at birth and throughout the postnatal course including intracellular TNF expression upon LPS stimulation. Complementing these measurements, cytokine end growth factor expression profiles (Luminex® xMAP®; n=110 infants) as well as gene expression profiles (CodeLinkTM Human I Bioarray; n=22) were characterized at birth.

Results

The abundance of monocyte subtypes differed between preterm and term neonates at birth. Specifically, CD14++CD16+ (intermediate) monocytes demonstrated a dependency on PMA and elevated levels of nonclassical (CD14+CD16++) monocytes characterized preterm infants with developing BPD. Postnatally, lung injury was associated with an increase in intermediate monocytes, while high levels of nonclassical monocytes persisted. Both subtypes were revealed as the main source of intracellular TNF-α expression in the preterm infant. We identified a cytokine and growth factor expression profile in cord blood specimen of preterm infants with developing BPD that corresponded to the disease-dependent regulation of monocyte abundances. Multivariate modeling of protein profiles revealed FGF2, sIL-2 Rα, MCP-1, MIP1a, and TNF-α as predictors of BPD when considering GA. Transcriptome analysis demonstrated genes predicting BPD to be overrepresented in inflammatory pathways with increased disease severity characterized by the regulation of immune and defense response pathways and upstream regulator analysis confirmed TNF-α, interleukin (IL) -6, and interferon α as the highest activated cytokines in more severe disease. Whereas all BPD cases showed downstream activation of chemotaxis and activation of inflammatory response pathways, more severe cases were characterized by an additional activation of reactive oxygen species (ROS) synthesis.

Discussion

In the present study, we identified the early postnatal presence of nonclassical (CD14+CD16++) and intermediate (CD14++CD16+) monocytes as a critical characteristic of BPD development including a specific response pattern of monocyte subtypes to lung injury. Pathophysiological insight was provided by the protein and transcriptome signature identified at birth, centered around monocyte and corresponding granulocyte activation and highlighting TNFα as a critical regulator in infants with developing BPD. The disease severity-dependent expression patterns could inform future diagnostic and treatment strategies targeting the monocytic cell and its progeny.

Growth and Duration of Inflammation Determine Short- and Long-Term Outcome in Very-Low-Birth-Weight Infants Requiring Abdominal Surgery

Necrotizing enterocolitis (NEC), spontaneous intestinal perforation (SIP) and meconium-related ileus (MI) requiring surgical intervention are associated with a high risk of severe short- and long-term complications in very-low-birth-weight (VLBW) infants including poor growth, cholestasis and neurodevelopmental impairment. This retrospective study aimed to identify risk factors for such complications in a cohort of 55 VLBW preterm infants requiring surgery with enterostomy creation due to NEC, SIP or MI. Long-term follow-up was available for 43 (78%) infants. Multiple regression analyses revealed that the duration of inflammation and longitudinal growth determined the risk of cholestasis and neurodevelopmental outcome at 2 years corrected age independent of the aetiology of the intestinal complication. Direct bilirubin increased by 4.9 μmol/L (95%CI 0.26-9.5), 1.4 μmol/L (95%CI 0.6-2.2) and 0.8 μmol/L (95%CI 0.22-1.13) with every day of elevated (Interleukin-6) IL-6, (C-reactive protein) CrP and parenteral nutrition. The mental development index at 2 years corrected age decreased by 3.8 (95%CI -7.3--0.36), 0.4 (95%CI 0.07-0.80) and 0.3 (95%CI 0.08-0.57) with every day of elevated IL-6 and every 1 point decrease in weight percentile at discharge and 2 years. These data stress the importance of optimal timing for the initial surgery in order to prevent prolonged inflammation and an early reversal of the enterostomy in case of poor growth or insufficient enteral nutrition.

Preterm Birth, Developmental Smoke/Nicotine Exposure, and Life-Long Pulmonary Sequelae

This review delineates the main pulmonary issues related to preterm birth, perinatal tobacco/nicotine exposure, and its effects on offspring, focusing on respiratory health and its possible transmission to subsequent generations. We review the extent of the problem of preterm birth, prematurity-related pulmonary effects, and the associated increased risk of asthma later in life. We then review the impact of developmental tobacco/nicotine exposure on offspring asthma and the significance of transgenerational pulmonary effects following perinatal tobacco/nicotine exposure, possibly via its effects on germline epigenetics.

High Glucose Promotes Inflammation and Weakens Placental Defenses against E. coli and S. agalactiae Infection: Protective Role of Insulin and Metformin

Placentas from gestational diabetes mellitus (GDM) patients undergo significant metabolic and immunologic adaptations due to hyperglycemia, which results in an exacerbated synthesis of proinflammatory cytokines and an increased risk for infections. Insulin or metformin are clinically indicated for the treatment of GDM; however, there is limited information about the immunomodulatory activity of these drugs in the human placenta, especially in the context of maternal infections. Our objective was to study the role of insulin and metformin in the placental inflammatory response and innate defense against common etiopathological agents of pregnancy bacterial infections, such as E. coli and S. agalactiae, in a hyperglycemic environment. Term placental explants were cultivated with glucose (10 and 50 mM), insulin (50–500 nM) or metformin (125–500 µM) for 48 h, and then they were challenged with live bacteria (1 × 105 CFU/mL). We evaluated the inflammatory cytokine secretion, beta defensins production, bacterial count and bacterial tissue invasiveness after 4–8 h of infection. Our results showed that a GDM-associated hyperglycemic environment induced an inflammatory response and a decreased beta defensins synthesis unable to restrain bacterial infection. Notably, both insulin and metformin exerted anti-inflammatory effects under hyperglycemic infectious and non-infectious scenarios. Moreover, both drugs fortified placental barrier defenses, resulting in reduced E. coli counts, as well as decreased S. agalactiae and E. coli invasiveness of placental villous trees. Remarkably, the double challenge of high glucose and infection provoked a pathogen-specific attenuated placental inflammatory response in the hyperglycemic condition, mainly denoted by reduced TNF-α and IL-6 secretion after S. agalactiae infection and by IL-1β after E. coli infection. Altogether, these results suggest that metabolically uncontrolled GDM mothers develop diverse immune placental alterations, which may help to explain their increased vulnerability to bacterial pathogens.

Impaired pulmonary function mediates the impact of preterm birth on later-life stroke: a 2-step, multivariable Mendelian randomization study

OBJECTIVES

Observational studies have suggested an association between preterm birth and stroke in late adulthood, but it remains unclear whether the association is causal. The purpose of this study was to evaluate the causal effects of gestational age on stroke and to determine the pathophysiological mechanisms underlying the causal associations.

METHODS

Two-sample Mendelian randomization (MR) was performed to assess the causal effects of fetal gestational duration, early preterm birth (EPB), preterm birth, or postterm birth on stroke and its subtypes. Two-step Mendelian randomization (TSMR) and multivariable Mendelian randomization (MVMR) were additionally used to determine the role of common stroke risk factors, including cardiovascular diseases, hypertension, pulmonary impairment, inflammation, and metabolic diseases, in mediating the causal associations between gestational age and stroke and its subtypes.

RESULTS

Genetically predicted EPB increased the risk of cardioembolic stroke (CES; odds ratio [OR], 1.115; 95% confidence interval [CI], 1.036 to 1.200; p=0.004) and large artery stroke (LAS; OR, 1.131; 95% CI, 1.031 to 1.241; p=0.009). The TSMR results showed that EPB was associated with a lower forced expiratory volume in the first second and forced vital capacity ratio (FEV1/FVC) (β=-0.020; 95% CI, -0.035 to -0.005; p=0.009), which increased the risk of CES and LAS. Further MVMR analysis showed that the associations between EPB and stroke disappeared after adjustment for FEV1/FVC.

CONCLUSIONS

Our data demonstrate that EPB is causally associated with an elevated risk of CES and LAS, and that pulmonary dysfunction mediates the causal impact of EPB on CES and LAS.

Imbalanced Inflammatory Responses in Preterm and Term Cord Blood Monocytes and Expansion of the CD14+CD16+ Subset upon Toll-like Receptor Stimulation

Developmentally regulated features of innate immunity are thought to place preterm and term infants at risk of infection and inflammation-related morbidity. Underlying mechanisms are incompletely understood. Differences in monocyte function including toll-like receptor (TLR) expression and signaling have been discussed. Some studies point to generally impaired TLR signaling, others to differences in individual pathways. In the present study, we assessed mRNA and protein expression of pro- and anti-inflammatory cytokines in preterm and term cord blood (CB) monocytes compared with adult controls stimulated ex vivo with Pam3CSK4, zymosan, polyinosinic:polycytidylic acid, lipopolysaccharide, flagellin, and CpG oligonucleotide, which activate the TLR1/2, TLR2/6, TLR3, TLR4, TLR5, and TLR9 pathways, respectively. In parallel, frequencies of monocyte subsets, stimulus-driven TLR expression, and phosphorylation of TLR-associated signaling molecules were analyzed. Independent of stimulus, pro-inflammatory responses of term CB monocytes equaled adult controls. The same held true for preterm CB monocytes-except for lower IL-1β levels. In contrast, CB monocytes released lower amounts of anti-inflammatory IL-10 and IL-1ra, resulting in higher ratios of pro-inflammatory to anti-inflammatory cytokines. Phosphorylation of p65, p38, and ERK1/2 correlated with adult controls. However, stimulated CB samples stood out with higher frequencies of intermediate monocytes (CD14⁺CD16⁺). Both pro-inflammatory net effect and expansion of the intermediate subset were most pronounced upon stimulation with Pam3CSK4 (TLR1/2), zymosan (TR2/6), and lipopolysaccharide (TLR4). Our data demonstrate robust pro-inflammatory and yet attenuated anti-inflammatory responses in preterm and term CB monocytes, along with imbalanced cytokine ratios. Intermediate monocytes, a subset ascribed pro-inflammatory features, might participate in this inflammatory state.

Causes of preterm birth: Genetic factors in preterm birth and preterm infant phenotypes

AIM

The aim is to provide an overview of recent research on genetic factors that influence preterm birth in the context of neonatal phenotypic assessment.

METHODS

This is a nonsystematic review of the recent scientific literature.

RESULTS

Maternal and fetal genetic diversity and rare genome variants are linked with crucial immune response sites. In addition, more frequent in preterm neonates, de novo variants may lead to attention deficits, hyperactivity, autism spectrum disorders, and infertility of both sexes later in life. Environmental factors may also greatly burden fetal, and consequently, neonatal development and neurodevelopment through a failure in the fetal epigenome reprogramming process and even influence the initiation of spontaneous preterm pregnancy termination. Minimally invasive analysis of the transcription factors associated with preterm birth helps elucidate labor mechanisms and predict its timing. We also provide valuable summaries of genomic and transcriptomic factors that contribute to preterm birth.

CONCLUSIONS

Investigation of the human genome, epigenome, and transcriptome helps to identify molecular mechanisms linked with preterm delivery and premature newborn clinical appearance in early and late neonatal life and even predict developmental outcomes. Further studies are needed to fully understand the implications of genetic changes in preterm births. These data could be used to develop targeted interventions aimed at selecting the most effective individual treatment and rehabilitation plan.

Decreased expression of hypoxia-inducible factor 1α (HIF-1α) in cord blood monocytes under anoxia

BACKGROUND

Infections are a major cause for morbidity and mortality in neonates; however, the underling mechanisms for increased infection susceptibility are incompletely understood. Hypoxia, which is present in inflamed tissues, has been identified as an important activation signal for innate immune cells in adults and is mainly mediated by hypoxia-inducible factor 1α (HIF-1α). Fetal tissue pO₂ physiologically is low but rises immediately after birth.

METHODS

In this study, the effect of low oxygen partial pressure (pO₂) on HIF-1α expression and its targets phagocytosis, reactive oxygen species (ROS) production and vascular endothelial growth factor (VEGF) secretion was compared in vitro between immune cells from adult peripheral blood and cord blood using anoxia, HIF-1α stabilizer desferroxamin (DFO) and E. coli as stimuli.

RESULTS

We show that anoxia-induced HIF-1α protein accumulation, phagocytosis, ROS-production and VEGF-expression were greatly diminished in cord blood compared to adult cells. E. coli led to HIF-1α gene expression in adult and cord blood immune cells; however, cord blood cells failed to accumulate HIF-1α protein and VEGF upon E. coli stimulation.

CONCLUSIONS

Taken together, our results show a diminished activation of cord blood immune cells by low pO₂, which might contribute to impaired reactivity in the context of infection.

IMPACT

Neonatal immune cells do not accumulate HIF-1α under low oxygen partial pressure leading to decreased phagocytosis and decreased ROS production. We demonstrate a previously unknown mechanism of reduced activation of neonatal immune cells in the context of an inflammatory response. This could contribute to the increased susceptibility of newborns and preterm infants to infection.

CpG methylation patterns in placenta and neonatal blood are differentially associated with neonatal inflammation

BACKGROUND

Infants born extremely premature are at increased risk for health complications later in life for which neonatal inflammation may be a contributing biological driver. Placental CpG methylation provides mechanistic information regarding the relationship between prenatal epigenetic programming, prematurity, neonatal inflammation, and later-in-life health.

METHODS

We contrasted CpG methylation in the placenta and neonatal blood spots in relation to neonatal inflammation in the Extremely Low Gestational Age Newborn (ELGAN) cohort. Neonatal inflammation status was based on the expression of six inflammation-related proteins, assessed as (1) day-one inflammation (DOI) or (2) intermittent or sustained systemic inflammation (ISSI, inflammation on ≥2 days in the first 2 postnatal weeks). Epigenome-wide CpG methylation was assessed in 354 placental samples and 318 neonatal blood samples.

RESULTS

Placental CpG methylation displayed the strongest association with ISSI (48 CpG sites) but was not associated with DOI. This was in contrast to CpG methylation in blood spots, which was associated with DOI (111 CpG sites) and not with ISSI (one CpG site).

CONCLUSIONS

Placental CpG methylation was strongly associated with ISSI, a measure of inflammation previously linked to later-in-life cognitive impairment, while day-one neonatal blood methylation was associated with DOI.

IMPACT

Neonatal inflammation increases the risk of adverse later-life outcomes, especially in infants born extremely preterm. CpG methylation in the placenta and neonatal blood spots were evaluated in relation to neonatal inflammation assessed via circulating proteins as either (i) day-one inflammation (DOI) or (ii) intermittent or sustained systemic inflammation (ISSI, inflammation on ≥2 days in the first 2 weeks). Tissue specificity was observed in epigenetic-inflammatory relationships: placental CpG methylation was associated with ISSI, neonatal blood CpG methylation was associated with DOI. Supporting the placental origins of disease framework, placental epigenetic patterns are associated with a propensity for ISSI in neonates.

Molecular Mechanisms of Hyperoxia-Induced Neonatal Intestinal Injury

Oxygen therapy is important for newborns. However, hyperoxia can cause intestinal inflammation and injury. Hyperoxia-induced oxidative stress is mediated by multiple molecular factors and leads to intestinal damage. Histological changes include ileal mucosal thickness, intestinal barrier damage, and fewer Paneth cells, goblet cells, and villi, effects which decrease the protection from pathogens and increase the risk of necrotizing enterocolitis (NEC). It also causes vascular changes with microbiota influence. Hyperoxia-induced intestinal injuries are influenced by several molecular factors, including excessive nitric oxide, the nuclear factor-κB (NF-κB) pathway, reactive oxygen species, toll-like receptor-4, CXC motif ligand-1, and interleukin-6. Nuclear factor erythroid 2-related factor 2 (Nrf2) pathways and some antioxidant cytokines or molecules including interleukin-17D, n-acetylcysteine, arginyl-glutamine, deoxyribonucleic acid, cathelicidin, and health microbiota play a role in preventing cell apoptosis and tissue inflammation from oxidative stress. NF-κB and Nrf2 pathways are essential to maintain the balance of oxidative stress and antioxidants and prevent cell apoptosis and tissue inflammation. Intestinal inflammation can lead to intestinal damage and death of the intestinal tissue, such as in NEC. This review focuses on histologic changes and molecular pathways of hyperoxia-induced intestinal injuries to establish a framework for potential interventions.

Contribution of Fetal Inflammatory Response Syndrome (FIRS) with or without Maternal-Fetal Inflammation in The Placenta to Increased Risk of Respiratory and Other Complications in Preterm Neonates

This study classifies fetal inflammatory response syndrome (FIRS) based on the presence or absence of maternal-fetal inflammation in the placenta and clarifies the association of FIRS with neonatal morbidities. Women (330) who delivered at gestational ages of 22w0d-33w6d were enrolled and grouped into four based on FIRS and maternal/fetal inflammatory response (MIR/FIR) statuses: Group A: without FIRS and MIR/FIR (reference group); Group B: MIR/FIR alone; Group C: FIRS and MIR/FIR; and Group D: FIRS without MIR/FIR. The associations between bronchopulmonary dysplasia (BPD), adverse neonatal outcomes, extremely low gestational age and Groups B, C, and D were investigated after adjustment for potential confounders. Among patients with FIRS, 29% were in Group D. The risk of BPD was increased in Groups C (adjusted odds ratio (aOR): 3.36; 95% confidence interval (CI): 1.14-9.89) and D (aOR: 4.17; 95% CI: 1.03-16.9), as was the risk of adverse neonatal outcomes (Group C: aOR: 7.17; 95% CI: 2.56-20.1; Group D: aOR: 6.84; 95% CI: 1.85-25.2). The risk of extremely low gestational age was increased in Group D (aOR: 3.85; 95% CI: 1.56-9.52). Therefore, FIRS without MIR/FIR is not rare and may be associated with neonatal morbidities more than FIRS and MIR/FIR.

The Molecular and Histopathological Assessment of Inflammatory Status in Very and Extremely Premature Infants: A Prospective Study

Prematurity comes with a varying range of complications, implying a high prevalence of complications and mortality and depending on the severity of prematurity and the sustained inflammation among these infants, which recently sparked an important scientific interest. The primary objective of this prospective study was to establish the degree of inflammation in very (VPIs) and extremely preterm infants (EPIs) in association with the histology findings of the umbilical cord (UC), while the secondary objective was to study the inflammatory markers in the neonates' blood as predictors of fetal inflammatory response (FIR). A total of thirty neonates were analyzed, ten of them being born extremely premature (<28 weeks of gestation) and twenty very premature (28-32 weeks of gestation). The EPIs had considerably higher levels of IL-6 at birth than VPIs (638.2 pg/mL vs. 151.1 pg/mL). The CRP levels at delivery did not vary substantially across groups; however, after days, the EPIs had significantly higher CRP levels (11.0 mg/dL vs. 7.2 mg/dL). In contrast, the LDH was considerably higher in the extremely preterm infants at birth and four days after birth. Surprisingly, the proportions of infants with pathologically increased inflammatory markers did not differ between the EPIs and VPIs. The LDH increased considerably in both groups, although the CRP levels increased exclusively among the VPIs. The stage of inflammation in the UC did not vary substantially between the EPIs and VPIs. The majority of infants were identified with Stage 0 UC inflammation (40% in EPI vs. 55% in VPIs). There was a substantial correlation link between gestational age and newborn weight and a significant inverse correlation among gestational age and IL-6 and LDH levels. There was a strong negative association between weight and IL-6 (rho = -0.349) and LDH (rho = -0.261). The stage of the UC inflammation demonstrated a statistically significant direct connection with IL-6 (rho = 0.461) and LDH (rho = 0.293), but none with the CRP. Further studies involving a bigger population size of preterm newborns are required to validate the findings and analyze more inflammatory markers, while prediction models on inflammatory markers that are measured expectantly, before the onset of preterm labor, need to be created.

Preterm infant body composition, working memory, and temperament

Altered body composition in preterm infants is associated with risks to cognitive development, but the effect specific to prefrontal cortex (PFC) development is unknown. We were interested in the impact of fat mass (FM) and fat free mass (FFM) gains out to 4 months corrected gestational age (CGA) on PFC development, as indexed by working memory and temperament. This is a prospective observational pilot study recruiting 100 preterm (<33 weeks gestation), appropriate for gestational age, and very low birth weight infants, of which 49 infants met inclusion criteria. Body composition was measured using air displacement plethysmography at hospital discharge and 4 months CGA. Questionnaire based temperament assessments were completed at 12 and 24 months CGA and a working memory assessment was completed at 24 months CGA. Associations between developmental tests and body composition obtained at term and 4 months were analyzed. Increased FM at discharge was associated with increased fear and decreased soothability at 12 months. Increased FM at 4 months was associated with increased activity level, increased distress from limitations at 12 months and decreased attentional shifting, decreased frustration, and decreased inhibitory control at 24 months. Increased FFM at 4 months was associated with increased activity level at 12 months and increased impulsivity and decreased low intensity pleasure at 24 months. In this exploratory pilot study, increased FM out to 4 months and increased FFM after discharge are associated with negative markers of infant temperament. Infant temperament may be sensitive to body composition status at least to 4 months CGA.