Microglial polarization in Alzheimer's disease: Mechanisms, implications, and therapeutic opportunities

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid-β plaques, neurofibrillary tangles, and chronic neuroinflammation. Microglial cells, the resident immune cells in the central nervous system, play a crucial role in the pathogenesis of AD. Microglia can undergo polarization, shifting between pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes in response to different stimuli. Dysregulation of microglial polarization towards the pro-inflammatory phenotype leads to the release of inflammatory cytokines, oxidative stress, and synaptic dysfunction. These processes contribute to neuronal damage and cognitive decline in AD. However, several challenges remain in this field. The complex molecular mechanisms governing microglial polarization in AD need to be further elucidated. In this review, we discuss the mechanisms underlying microglial polarization in AD and its implications in disease progression.