Microglia, neuroinflammation, and beta-amyloid protein in Alzheimer's disease

Compelling evidence from basic molecular biology has demonstrated the dual roles of microglia in the pathogenesis of Alzheimer's disease (AD). On one hand, microglia are involved in AD pathogenesis by releasing inflammatory mediators such as inflammatory cytokines, complement components, chemokines, and free radicals that are all known to contribute to beta-amyloid (Aβ) production and accumulation. On the other hand, microglia are also known to play a beneficial role in generating anti-Aβ antibodies and stimulating clearance of amyloid plaques. Aβ itself, an inducer of microglia activation and neuroinflammation, has been considered as an underlying and unifying factor in the development of AD. A vicious cycle…