Join us in this enlightening episode with Dr. Bolton, who explores the fascinating relationships between early-life adversity (ELA), the maturation of stress-related brain circuits, and subsequent mental health vulnerabilities. Her recent study delves into the profound ways ELA influences brain development, specifically impacting the hypothalamic corticotropin-releasing hormone (CRH) neurons.

Dr. Bolton reveals that ELA increases functional excitatory synapses onto these stress-sensitive neurons, disrupting the typical developmental synapse pruning process performed by adjacent microglia. The disrupted activity of these microglia is connected to diminished signaling of the microglial phagocytic receptor MerTK in mice exposed to ELA.

This intricate neural dance doesn't stop there. Dr. Bolton delves deeper, sharing how selective chronic chemogenetic activation of ELA microglia can help increase microglial process dynamics and reduce excitatory synapse density to control levels. Notably, such selective activation during early life can normalize adult acute and chronic stress responses, hormonal stress-induced secretion, and even behavioral threat responses.

As we navigate through this complex world of early-life stress and its long-term impact on stress regulation and mental health, Dr. Bolton's insights shed valuable light. The episode underscores the critical role of microglial actions during development and how they shape our stress-response system, adding a fresh perspective to the discussion of mental illnesses arising from early-life stress.

Intrigued about the power of early-life events on your brain and mental health? Tune into this episode and uncover the fascinating mechanisms of stress regulation with Dr. Bolton!

https://doi.org/10.1016/j.celrep.2022.110600