The Blood-Cerebrospinal Fluid Barrier Dysfunction in Brain Disorders and Stroke: Why, How, What For?

Ischemic stroke (IS) results in the interruption of blood flow to the brain, which can cause significant damage. The pathophysiological mechanisms of IS include ionic imbalances, oxidative stress, neuroinflammation, and impairment of brain barriers. Brain barriers, such as the blood–brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (B-CSF), protect the brain from harmful substances by regulating the neurochemical environment. Although the BBB is widely recognized for its crucial role in protecting the brain and its involvement in conditions such as stroke, the B-CSF requires further study. The B-CSF plays a fundamental role in regulating the CSF environment and maintaining the homeostasis of the central nervous system (CNS). However, the impact of B-CSF impairment during pathological events such as IS is not yet fully understood. In conditions like IS and other neurological disorders, the B-CSF can become compromised, allowing the entry of inflammatory substances and increasing neuronal damage. Understanding and preserving the integrity of the B-CSF are crucial for mitigating damage and facilitating recovery after ischemic stroke, highlighting its fundamental role in regulating the CNS during adverse neurological conditions.