These are accompanied by reactive microglia and astrocytes in the vicinity of the neuritic plaques and by changes to the peripheral immune system, e.g., an increase of the pro-inflammatory cytokines IL-1β, IL-6, and TNF-α in the peripheral blood.
Since complex interactions among cytokines have been suggested around senile plaques in Alzheimer's disease, TNF might be associated with ageing and the pathophysiology of Alzheimer's disease.
Tumor necrosis factor (TNF), a proinflammatory cytokine, may be involved in the pathogenesis of Alzheimer disease (AD) based on observations that senile plaques have been found to upregulate proinflammatory cytokines.