Glial Cells in Alzheimer's Disease: Pathogenic Mechanisms and Therapeutic Frontiers

The rising incidence of brain diseases parallels the global trend of an aging population, with Alzheimer's disease (AD) being a leading neurodegenerative disorder characterized by memory loss, dementia, and cognitive decline. Despite extensive research, current treatments for AD remain largely symptomatic and have had limited success in halting disease progression, thereby shifting attention toward glial cells as promising therapeutic targets due to their emerging roles in AD pathogenesis. Astrocytes are involved in both beneficial and pathological processes in AD, such as cytokine secretion, Aβ removal, metabolic support, and tau pathology, with deficiency resulting in neuroinflammation and excitotoxicity. Microglia have dual functions in AD by phagocytosing amyloid plaques and limiting tau spread in initial phases but may develop a pro-inflammatory, neurodegenerative phenotype with progression of the disease. Oligodendrocytes and their precursors are involved in Aβ generation and myelin homeostasis, and their disturbance is responsible for white matter lesions and cognitive impairment, though their exact mechanisms are less clear. This review also examines emerging therapeutic strategies targeting glial cells, including modulating TREM2 pathways and novel drug candidates. These methods highlight the therapeutic value of the glial cells and provide valuable leads for furthering the treatment of AD by elucidating their changing roles in the course of the disease.