Barrier function in the peripheral and central nervous system-a review.
The peripheral (PNS) and central nervous system (CNS) are delicate structures, highly sensitive to homeostatic changes-and crucial for basic vital functions. Thus, a selection of barriers ensures the protection of the nervous system from noxious blood-borne or surrounding stimuli. In this chapter, anatomy and functioning of the blood-nerve (BNB), the blood-brain (BBB), and the blood-spinal cord barriers (BSCB) are presented and the key tight junction (TJ) proteins described: claudin-1, claudin-3, claudin-5, claudin-11, claudin-12, claudin-19, occludin, Zona occludens-1 (ZO-1), and tricellulin are by now identified as relevant for nerval barriers. Different diseases can lead to or be accompanied by neural barrier disruption, and impairment of these barriers worsens pathology. Peripheral nerve injury and inflammatory polyneuropathy cause an increased permeability of BNB as well as BSCB, while, e.g., diseases of the CNS such as amyotrophic lateral sclerosis, multiple sclerosis, spinal cord injury, or Alzheimer's disease can progress and worsen through barrier dysfunction. Moreover, the complex role and regulation of the BBB after ischemic stroke is described. On the other side, PNS and CNS barriers hamper the delivery of drugs in diseases when the barrier is intact, e.g., in certain neurodegenerative diseases or inflammatory pain. Understanding of the barrier - regulating processes has already lead to the discovery of new molecules as drug enhancers. In summary, the knowledge of all of these mechanisms might ultimately lead to the invention of drugs to control barrier function to help ameliorating or curing neurological diseases.
['Reinhold|A K|AK|', 'Rittner|H L|HL|']
D000818:Animals D001812:Blood-Brain Barrier D002490:Central Nervous System D006801:Humans D062793:Occludin D017933:Peripheral Nervous System D013116:Spinal Cord D062725:Tight Junction Proteins D019108:Tight Junctions
Tight junction Occludin ZO-1 Tricellulin Nerve injury Inflammatory polyneuropathy Amyotrophic lateral sclerosis Multiple sclerosis Spinal cord injury Ischemic stroke Alzheimer’s disease Barrier opening Blood–brain barrier Blood–nerve barrier Blood–spinal cord barrier Claudin Drug delivery