Inflammation and the developing brain: Consequences for hippocampal neurogenesis and behavior

• Maternal inflammation during pregnancy elicits inflammation in utero.
• The developing hippocampus is vulnerable to an inflammatory insult.
• Prenatal inflammation can have life-long consequences for hippocampal neurogenesis.
• Decreased hippocampal neurogenesis may have behavioral consequences.
• Exposure to inflammation in utero can have life-long behavioral consequences.

While the detrimental impact of inflammation on adult hippocampal neurogenesis and associated behaviors has recently gained credence, the effects of inflammation on the developing brain is an area of research which is quickly gaining momentum, and a growing number of research articles on this topic have been published in recent years. Indeed, we now know that pro-inflammatory mediators negatively influence both hippocampal neurogenesis and neuronal cytoarchitecture during brain development. Here we present a comprehensive review of the current literature on inflammation-induced changes in hippocampal neurogenesis during early life and the consequent behavioral deficits which may ensue in later life. We also offer insights into the cellular and molecular mechanisms underlying the hippocampal-dependant behavioral changes observed in neurodevelopmental disorders, particularly in those where cognitive dysfunction plays a major role. We further consider whether early-life inflammation-induced changes in hippocampal neurogenesis may contribute to the onset of mood and cognitive deficits in later life.