Neuroinflammation is an inflammatory response in the tissue of the nervous system. Its main players are microglia (the brain’s own immune cells) and astrocytes. Normally inflammation protects the brain, but prolonged, chronic inflammation harms neurons.
Microglia and astrocytes
Microglia constantly “patrol” the brain and react to damage and pathogens. When activated, microglia and astrocytes release inflammatory signals — the interleukins IL-1β, IL-6 and tumor necrosis factor (TNF-α). In the short term this helps clear damaged cells and debris.
Acute and chronic inflammation
Acute neuroinflammation is a protective and usually helpful response. The problem arises when inflammation becomes chronic and low-grade (part of so-called “inflammaging”): it damages neurons and synapses and sustains neurodegeneration. Systemic inflammation is also linked to the level of C-reactive protein.
The role in aging and dementia
Chronic neuroinflammation is considered one of the mechanisms that raise the risk of and accelerate Alzheimer’s disease. With age the microglia themselves “age”: they accumulate iron, engage autophagy less well and release damaging substances more actively. Meanwhile the direction of causality (what comes first — amyloid or inflammation) remains a matter of debate.
What lowers neuroinflammation
There are no reliable “anti-inflammatory pills for the brain.” But regular physical activity, adequate sleep, control of obesity, diabetes and blood pressure, and a healthy diet are associated with lower systemic and, probably, neuroinflammation. The evidence base is still forming.
Calculate using this marker
Calculators where Neuroinflammation is used directly:
Frequently asked questions
Is neuroinflammation always bad?
No. Acute inflammation protects the brain and helps clear damaged cells. It becomes harmful when it turns chronic and low-grade, damaging neurons and sustaining neurodegeneration.
Can neuroinflammation be measured with a blood test?
There is no direct routine test. Systemic inflammation is judged indirectly by markers such as C-reactive protein, but they are not specific to the brain. Assessing neuroinflammation is still mostly a research matter (PET, cerebrospinal fluid).
Related terms
Sources
- Roles of microglia and astrocytes in neuroinflammation of Alzheimer’s disease (PMC)
- The role of microglia in Alzheimer’s disease (PMC)