Maternal respiratory viral infections during pregnancy and offspring's neurodevelopmental outcomes: a systematic review

Sex-Specific Behavioral and Molecular Responses to Maternal Lipopolysaccharide-Induced Immune Activation in a Murine Model: Implications for Neurodevelopmental Disorders

Maternal immune activation (MIA) during pregnancy has been increasingly recognized as a critical factor in the development of neurodevelopmental disorders, with potential sex-specific impacts that are not yet fully understood. In this study, we utilized a murine model to explore the behavioral and molecular consequences of MIA induced by lipopolysaccharide (LPS) administration on embryonic day 12.5. Our findings indicate that male offspring exposed to LPS exhibited significant increases in anxiety-like and depression-like behaviors, while female offspring did not show comparable changes. Molecular analyses revealed alterations in pro-inflammatory cytokine levels and synaptic gene expression in male offspring, suggesting that these molecular disruptions may underlie the observed behavioral differences. These results emphasize the importance of considering sex as a biological variable in studies of neurodevelopmental disorders and highlight the need for further molecular investigations to understand the mechanisms driving these sex-specific outcomes. Our study contributes to the growing evidence that prenatal immune challenges play a pivotal role in the etiology of neurodevelopmental disorders and underscores the potential for sex-specific preventative approaches of MIA.

Positive Autism Screening Rates in Toddlers Born During the COVID-19 Pandemic

Importance

Stress and viral illness during pregnancy are associated with neurodevelopmental conditions in offspring. Autism screening positivity for children born during the pandemic remains unknown.

Objective

To examine associations between prenatal exposure to the pandemic milieu and maternal SARS-CoV-2 infection with rates of positive Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R) screenings.

Design, Setting, and Participants

Data for this cohort study were drawn from the COVID-19 Mother Baby Outcomes (COMBO) Initiative. M-CHAT-R scores obtained from children aged 16 to 30 months during routine clinical care at Columbia University Irving Medical Center in New York City were abstracted from electronic health records (EHRs) for children born between January 2018 and September 2021 (COMBO-EHR cohort). Separately, the M-CHAT-R was administered at 18 months for children born between February 2020 and September 2021 through a prospective longitudinal study (COMBO-RSCH cohort). Prenatal pandemic exposure (birth after March 1, 2020) and maternal SARS-CoV-2 status during pregnancy was determined through EHRs. Data were analyzed from March 2022 to June 2024.

Exposures

Prenatal exposures to the pandemic milieu and maternal SARS-CoV-2 infection.

Main Outcomes and Measures

The primary outcome was rate of positive M-CHAT-R screenings. For all primary analyses, unadjusted χ2 tests and adjusted logistic regression models were performed.

Results

The COMBO-EHR cohort included 1664 children (442 born before the pandemic and 1222 born during the pandemic; 997 SARS-CoV-2 unexposed, 130 SARS-CoV-2 exposed, and 95 with unknown SARS-CoV-2 exposure status), of whom 266 (16.0%) were Black, 991 (59.6%) were Hispanic, 400 (24.0%) were White, 1245 (74.8%) were insured through Medicaid, 880 (52.9%) were male, and 204 (12.3%) were born prematurely. The COMBO-RSCH cohort included 385 children (74 born before the pandemic and 311 born during the pandemic; 201 SARS-CoV-2 unexposed, 101 SARS-CoV-2 exposed, and 9 with unknown SARS-CoV-2 exposure status), of whom 39 (10.1%) were Black, 168 (43.6%) were Hispanic, 157 (40.8%) were White, 161 (41.8%) were insured through Medicaid, 222 (57.7%) were male, and 38 (9.9%) were born prematurely. Prenatal pandemic exposure was not associated with a higher positive M-CHAT-R screening rate in either the COMBO-EHR or COMBO-RSCH cohort. Prenatal exposure to maternal SARS-CoV-2 infection was associated with a lower rate of M-CHAT-R positivity in the COMBO-EHR cohort (12.3% [16 children] vs 24.0% [239 children]; adjusted odds ratio, 0.40; 95% CI, 0.22-0.68; P = .001), but no association was found in the COMBO-RSCH cohort (12.9% [13 children] vs 19.9% [40 children]; adjusted odds ratio, 0.51; 95% CI, 0.24-1.04; P = .07).

Conclusions and Relevance

In this cohort study of 2 groups of children with prenatal pandemic exposure and/or exposure to maternal SARS-CoV-2 infection, neither exposure was associated with greater M-CHAT-R positivity.

Ventricular-subventricular zone stem cell niche adaptations in a mouse model of post-infectious hydrocephalus

Congenital post-infectious hydrocephalus (PIH) is a condition characterized by enlargement of the ventricular system, consequently imposing a burden on the associated stem cell niche, the ventricular-subventricular zone (V-SVZ). To investigate how the V-SVZ adapts in PIH, we developed a mouse model of influenza virus-induced PIH based on direct intracerebroventricular injection of mouse-adapted influenza virus at two distinct time points: embryonic day 16 (E16), when stem cells line the ventricle, and postnatal day 4 (P4), when an ependymal monolayer covers the ventricle surface and stem cells retain only a thin ventricle-contacting process. Global hydrocephalus with associated regions of astrogliosis along the lateral ventricle was found in 82% of the mice infected at P4. Increased ependymogenesis was observed at gliotic borders and throughout areas exhibiting intact ependyma based on tracking of newly divided cells. Additionally, in areas of intact ependyma, stem cell numbers were reduced; however, we found no significant reduction in new neurons reaching the olfactory bulb following onset of ventriculomegaly. At P4, injection of only the non-infectious viral component neuraminidase resulted in limited, region-specific ventriculomegaly due to absence of cell-to-cell transmission. In contrast, at E16 intracerebroventricular injection of influenza virus resulted in death at birth due to hypoxia and multiorgan hemorrhage, suggesting an age-dependent advantage in neonates, while the viral component neuraminidase resulted in minimal, or no, ventriculomegaly. In summary, we tracked acute adaptations of the V-SVZ stem cell niche following onset of ventriculomegaly and describe developmental changes that help mitigate the severity of congenital PIH.

Neonatal immune cells have heightened responses following in-utero exposure to chorioamnionitis or COVID-19

BACKGROUND

Chorioamnionitis alters neonatal immune responses. Gestational COVID-19 infection is associated with adverse pregnancy outcomes, but its impact on neonatal immunity is unclear. We hypothesized that gestational COVID-19 exposure would result in exaggerated neonatal immune responses, similar to chorioamnionitis-exposed neonates.

METHODS

Term umbilical cord blood mononuclear cells (CBMCs) were isolated from neonates exposed to chorioamnionitis, gestational COVID-19 or unexposed controls. CBMCs were cultured and stimulated with heat-killed Escherichia coli, Streptococcus agalactiae or Staphylococcus epidermidis. A multiplexed protein assay was used to measure cytokine levels in cell culture supernatants and flow cytometry was used to evaluate cellular-level cytokine expression.

RESULTS

Both chorioamnionitis-exposed and COVID-19 exposed CBMCs demonstrated upregulation of IL-1β and IL-6 compared to unexposed CBMCs, while only COVID-19 exposure resulted in IL-8 upregulation. There were no differences between chorioamnionitis-exposed and COVID-19 exposed CBMCs when these groups were directly compared. Flow cytometry demonstrated immune cell subset specific differences in cytokine expression between the exposure groups.

CONCLUSION

The fetal/neonatal response to maternal inflammation differed based on immune cell subset and etiology of inflammation, but the global neonatal cytokine responses were similar between exposure groups. This suggests that targeting perinatal inflammation rather than the specific etiology may be a possible therapeutic approach.

IMPACT

Neonatal immune cells have similar pathogen-associated global cytokine responses, but different cell-level immune responses, following in-utero exposure to chorioamnionitis or COVID-19. This is the first study to directly compare immune responses between neonates exposed to chorioamnionitis and COVID-19. This suggests that the fetal/neonatal cellular response to perinatal inflammation differs based on the etiology and severity of maternal inflammation, but still results in a similar overall inflammatory profile regardless of the cause of perinatal inflammation.

Gestational testosterone excess early to mid-pregnancy disrupts maternal lipid homeostasis and activates biosynthesis of phosphoinositides and phosphatidylethanolamines in sheep

Gestational hyperandrogenism is a risk factor for adverse maternal and offspring outcomes with effects likely mediated in part via disruptions in maternal lipid homeostasis. Using a translationally relevant sheep model of gestational testosterone (T) excess that manifests maternal hyperinsulinemia, intrauterine growth restriction (IUGR), and adverse offspring cardiometabolic outcomes, we tested if gestational T excess disrupts maternal lipidome. Dimensionality reduction models following shotgun lipidomics of gestational day 127.1 ± 5.3 (term 147 days) plasma revealed clear differences between control and T-treated sheep. Lipid signatures of gestational T-treated sheep included higher phosphoinositides (PI 36:2, 39:4) and lower acylcarnitines (CAR 16:0, 18:0, 18:1), phosphatidylcholines (PC 38:4, 40:5) and fatty acids (linoleic, arachidonic, Oleic). Gestational T excess activated phosphatidylethanolamines (PE) and PI biosynthesis. The reduction in key fatty acids may underlie IUGR and activated PI for the maternal hyperinsulinemia evidenced in this model. Maternal circulatory lipids contributing to adverse cardiometabolic outcomes are modifiable by dietary interventions.

Developmental impairment in children exposed during pregnancy to maternal SARS-COV2: A Brazilian cohort study

OBJECTIVES

To determine the effects of in-utero exposure to maternal SARS-CoV-2 infection on offspring's neurodevelopment during the first year of life.

METHODS

We performed a prospective cohort of babies exposed to SARS-CoV-2 during pregnancy, and a control group (CG) of unexposed babies in a low-income area in Brazil. Children's neurodevelopment was assessed using the guide for Monitoring Child Development in the Integrated Management of Childhood Illness context for both groups (at 1,2,3,4,5,6, 9, and 12 months), and the Ages & Stages Questionnaire (ASQ-3) for the exposed group (EG) (at 4, 6 and 12 months).

RESULTS

We followed 137 children for 1 year, 69 in the COVID-19-EG, and 68 in the CG. All mothers were unvaccinated at the time of cohort inclusion, and maternal demographics were similar in the two groups. 20.3% of EG children and 5.9% of the CG received a diagnosis of neurodevelopmental delay within 12 months of life (P = 0.013, relative risk = 3.44; 95% confidence interval, 1.19- 9.95). For the EG, the prevalence of neurodevelopment impairment using Ages & Stages Questionnaire was 35.7% at 4 months, 7% at 6 months, and 32.1% at 12 months.

CONCLUSION

SARS-CoV-2 exposure was associated with neurodevelopmental impairment, and specific guidelines are needed for the follow-up of these high-risk children to mitigate the long-term effects on children's health.

Impact of respiratory viral infections during pregnancy on the neurological outcomes of the newborn: current knowledge

Brain development is a complex process that begins during pregnancy, and the events occurring during this sensitive period can affect the offspring's neurodevelopmental outcomes. Respiratory viral infections are frequently reported in pregnant women, and, in the last few decades, they have been related to numerous neuropsychiatric sequelae. Respiratory viruses can disrupt brain development by directly invading the fetal circulation through vertical transmission or inducing neuroinflammation through the maternal immune activation and production of inflammatory cytokines. Influenza virus gestational infection has been consistently associated with psychotic disorders, such as schizophrenia and autism spectrum disorder, while the recent pandemic raised some concerns regarding the effects of severe acute respiratory syndrome coronavirus 2 on neurodevelopmental outcomes of children born to affected mothers. In addition, emerging evidence supports the possible role of respiratory syncytial virus infection as a risk factor for adverse neuropsychiatric consequences. Understanding the mechanisms underlying developmental dysfunction allows for improving preventive strategies, early diagnosis, and prompt interventions.

Maternal Influenza and Offspring Neurodevelopment

This review examines the complex interactions between maternal influenza infection, the immune system, and the neurodevelopment of the offspring. It highlights the importance of high-quality studies to clarify the association between maternal exposure to the virus and neuropsychiatric disorders in the offspring. Additionally, it emphasizes that the development of accurate animal models is vital for studying the impact of infectious diseases during pregnancy and identifying potential therapeutic targets. By drawing attention to the complex nature of these interactions, this review underscores the need for ongoing research to improve the understanding and outcomes for pregnant women and their offspring.

COVID-19 Infection during Pregnancy: Disruptions in Lipid Metabolism and Implications for Newborn Health

The COVID-19 pandemic has raised questions about indirect impact in pregnant women on the development of their future children. Investigating the characteristics of lipid metabolism in the "mother-placenta-fetus" system can give information about the pathophysiology of COVID-19 infection during pregnancy. A total of 234 women were included in study. Maternal plasma, cord blood, and amniotic fluid lipidome were analyzed using HPLC-MS/MS. Differences in lipid profile were searched by Mann-Whitney and Kruskall-Wallis test, and diagnostic model based on logistic regression were built by AIC. Elevated levels of lysophospholipids, triglycerides, sphingomyelins, and oxidized lipids were registered in patients' maternal and cord plasma after COVID-19 infection. An increase in maternal plasma sphingomyelins and oxidized lipids was observed in cases of infection during the second trimester. In amniotic fluid, compared to the control group, nine lipids were reduced and six were elevated. Levels of phosphoglycerides, lysophosphoglycerides, and phosphatidylinositols decreased during infection in the second and third trimesters of pregnancy. A health diagnostic model for newborns based on maternal plasma was developed for each group and exhibited good diagnostic value (AUC > 0.85). Maternal and cord plasma's lipidome changes during delivery, which are associated with COVID-19 infection during pregnancy, are synergistic. The most significant disturbances occur with infections in the second trimester of pregnancy.