[Neuronal regeneration and the glial barrier]

Area of Science:

• Neuroscience
• Cell Biology
• Regenerative Medicine

Context:

• The long-held belief of limited central nervous system (CNS) axon regeneration is being challenged.
• Recent advancements have identified key impediments to axonal regrowth in higher vertebrates.

Purpose:

• To review the progress in overcoming CNS axonal regeneration barriers.
• To highlight the role of inhibitory molecules and astrocyte responses.
• To introduce tanycytes as a potential substrate for regeneration.

Summary:

• Severed CNS axons can regrow in suitable environments, breaking Cajal's dogma.
• Inhibitory molecules from oligodendrocytes can be neutralized with antibodies, allowing some cortico-spinal axon regrowth.
• Pharmacological reduction of astrocyte hyperplasia aids monoaminergic axon regeneration in hemisected cords.
• Tanycytes, a type of hypothalamic astrocyte, are identified as permissive for axonal regeneration.

Impact:

• Advances in understanding and overcoming CNS injury limitations.
• Potential therapeutic strategies for neurological repair and functional recovery.
• Opens new research avenues for promoting axonal regeneration in the CNS.