How brain 'cleaners' fail: Mechanisms and therapeutic value of microglial phagocytosis in Alzheimer's disease

Glia. 2024 Feb;72(2):227-244. doi: 10.1002/glia.24465. Epub 2023 Aug 31.

Abstract

Microglia are the resident phagocytes of the brain, where they primarily function in the clearance of dead cells and the removal of un- or misfolded proteins. The impaired activity of receptors or proteins involved in phagocytosis can result in enhanced inflammation and neurodegeneration. RNA-seq and genome-wide association studies have linked multiple phagocytosis-related genes to neurodegenerative diseases, while the knockout of such genes has been demonstrated to exert protective effects against neurodegeneration in animal models. The failure of microglial phagocytosis influences AD-linked pathologies, including amyloid β accumulation, tau propagation, neuroinflammation, and infection. However, a precise understanding of microglia-mediated phagocytosis in Alzheimer's disease (AD) is still lacking. In this review, we summarize current knowledge of the molecular mechanisms involved in microglial phagocytosis in AD across a wide range of pre-clinical, post-mortem, ex vivo, and clinical studies and review the current limitations regarding the detection of microglia phagocytosis in AD. Finally, we discuss the rationale of targeting microglial phagocytosis as a therapeutic strategy for preventing AD or slowing its progression.

Keywords: Alzheimer's disease; microglia; phagocytosis; therapeutic targets.

Publication types

  • Review

MeSH terms

  • Alzheimer Disease* / pathology
  • Amyloid beta-Peptides / metabolism
  • Animals
  • Brain / metabolism
  • Genome-Wide Association Study
  • Microglia / metabolism
  • Phagocytosis

Substances

  • Amyloid beta-Peptides