Inflammation is the body’s first response to threat — a tightly coordinated mobilisation of immune cells to contain damage and initiate repair. In the brain, this response is managed by a specialised set of resident immune cells – microglia - and infiltrating peripheral immune cells governed by the blood-brain barrier, a selective boundary that normally limits what passes between the bloodstream and neural tissue. When these mechanisms are properly functioning, inflammation is brief, targeted, and followed by recovery. When they do not, it can become chronic, self-sustaining, and destructive.
Neuroinflammation — persistent inflammatory activity within the central nervous system — is now understood to be a driving factor in a wide range of conditions. In Multiple Sclerosis, it is the mechanism by which exacerbates the myelin destruction around the neuronal axons and impair oligodendrocyte remyelination. In Alzheimer’s Disease, chronic activation of microglia and accumulation of inflammatory signals around amyloid plaques appears to accelerate neuronal loss. In neurodevelopmental disorders, early-life inflammatory events may alter the trajectory of brain development in lasting ways.
A critical question in this field is how peripheral inflammation — inflammation originating outside the central nervous system, in response to infection, metabolic disease, or chronic stress — reaches and amplifies processes inside the brain. The blood-brain barrier integrity can be compromised by systemic inflammatory conditions. This connection between body-wide inflammation and neurological outcomes is a key focus of current research.
For brain regeneration, neuroinflammation is both an obstacle and a target. Any tissue repair strategy must consider the inflammatory environment associated to the disease. At the same time, inflammatory pathways, if modulated rather than simply suppressed, may themselves be part of the repair process.
