Can Consuming Flavonoids Restore Old Microglia to their Youthful State?

摘要

Microglial cells, resident macrophages in the central nervous system, are “primed” in the aged brain and are hypersensitive to messages emerging from immune-to-brain signaling pathways. Thus, in old individuals with an infection, microglia over react to signals from the peripheral immune system and produce excessive levels of cytokines causing behavioral pathology including serious deficits in cognition. Importantly, recent studies indicate dietary flavonoids have anti-inflammatory properties and are capable of mitigating microglial cells in the brain of aged mice. Thus, dietary or supplemental flavonoids and other bioactives have potential to restore the population of microglial cells in the old brain to its youthful state. This review briefly describes the immune-to-brain signaling pathways, consequences of microglial cell priming, and the potential of flavonoids to mitigate brain microglia and cognitive deficits induced by inflammatory cytokines.