Intrauterine Viral Infections: Impact of Inflammation on Fetal Neurodevelopment.

Sourav Ganguli,Pavithra L Chavali

doi:10.3389/fnins.2021.771557

Abstract

Intrauterine viral infections during pregnancy by pathogens such as Zika virus, Cytomegalovirus, Rubella and Herpes Simplex virus can lead to prenatal as well as postnatal neurodevelopmental disorders. Although maternal viral infections are common during pregnancy, viruses rarely penetrate the trophoblast. When they do cross, viruses can cause adverse congenital health conditions for the fetus. In this context, maternal inflammatory responses to these neurotropic pathogens play a significant role in negatively affecting neurodevelopment. For instance, intrauterine inflammation poses an increased risk of neurodevelopmental disorders such as microcephaly, schizophrenia, autism spectrum disorder, cerebral palsy and epilepsy. Severe inflammatory responses have been linked to stillbirths, preterm births, abortions and microcephaly. In this review, we discuss the mechanistic basis of how immune system shapes the landscape of the brain and how different neurotropic viral pathogens evoke inflammatory responses. Finally, we list the consequences of neuroinflammation on fetal brain development and discuss directions for future research and intervention strategies.

Highlights

Neurodevelopment is a complex developmental process that begins during the third week of gestation and continues postnatally until adulthood (Stiles and Jernigan, 2010)
In the sections that follow, we provide insights into how the proper functioning of the immune system is critical for brain development, and how prolonged inflammation caused by the maternal immune system in response to viral infections might jeopardize fetal neurodevelopment
Understanding the role of inflammation in neurodevelopmental disorders has opened up avenues for targeting the immune system of patients with neuropsychiatric disorders such as bipolar disorder, autism spectrum disorders (ASD) and schizophrenia

Summary

Introduction

Neurodevelopment is a complex developmental process that begins during the third week of gestation and continues postnatally until adulthood (Stiles and Jernigan, 2010). Microglia provide tropic support to the other major cells of brain such as astrocytes and neurons and facilitate response to signals received from the surrounding neural environment (Nayak et al, 2014; Prinz et al, 2019) (Figure 2). Immune cells defend against invading microbes and fight infection, but they contribute to the brain development through the secretion of unique molecules known as cytokines.

Results

Conclusion