Immature Neurons in the Postnatal Brain: Markers, Modulation, and Involvement in Normal and Aberrant Plasticity

Area of Science:

• Neuroscience
• Developmental Biology
• Cellular Plasticity

Background:

• Cortical immature neurons (cINs) are a unique population of prenatally generated, non-dividing neurons.
• They maintain an immature phenotype, marked by doublecortin (DCX) and polysialylated neural cell adhesion molecule (PSA-NCAM) expression, into adulthood.
• cINs represent a form of structural plasticity termed "neurogenesis without division," distinct from canonical adult neurogenesis.

Purpose of the Study:

• To comprehensively review the molecular markers, morphology, origins, and maturation of cINs across species.
• To examine factors influencing cIN phenotype and their clinical relevance in neurological conditions.
• To identify knowledge gaps and potential therapeutic applications of cIN biology.

Main Methods:

• Literature review of studies on cortical immature neurons.
• Comparative analysis of cIN abundance and canonical adult neurogenesis across mammalian lineages.
• Evaluation of clinical evidence linking cIN alterations to neurological disorders.

Main Results:

• An inverse relationship exists between cIN abundance and canonical adult neurogenesis across species.
• Factors like neurotransmitters, stress, sensory experience, and aging modulate cIN phenotype.
• cIN alterations are implicated in temporal lobe epilepsy, traumatic brain injury, and stroke.

Conclusions:

• Understanding cIN biology provides new perspectives on cortical plasticity.
• cINs may play roles in pathological remodeling and endogenous repair mechanisms.
• Further research into cINs could inform therapeutic strategies for brain repair targeting endogenous cellular reserves.