Senescent microglia: The hidden culprits accelerating Alzheimer's disease

Area of Science:

• Neuroscience
• Immunology
• Aging Research

Background:

• Aging is a primary risk factor for neurodegenerative diseases, including Alzheimer's disease (AD).
• Microglia, the brain's resident immune cells, play crucial roles in brain health but become dysfunctional with age.
• Age-related microglial dysfunction is increasingly recognized as a key driver of age-associated brain diseases.

Purpose of the Study:

• To review the detrimental effects of senescent microglia in aging and AD pathogenesis.
• To explore how factors secreted by senescent microglia contribute to AD hallmarks like Aβ accumulation and neuroinflammation.
• To highlight senescent microglia as a potential therapeutic target for neurodegenerative diseases.

Main Methods:

• Literature review focusing on immunomodulatory functions of factors secreted by senescent microglia.
• Analysis of alterations in microglial gene expression, morphology, and function in aging and AD.
• Examination of the impact of microglial secretomes on Aβ pathology, Tau deposition, synaptic dysfunction, and neuroinflammation.

Main Results:

• Senescent microglia secrete various factors, including cytokines, chemokines, complement factors, and reactive oxygen species (ROS).
• These secreted factors exacerbate Aβ accumulation, Tau deposition, synaptic dysfunction, and neuroinflammation in AD.
• Dysfunctional microglia significantly contribute to the progression of neurodegenerative pathologies.

Conclusions:

• Senescent microglia play a pivotal role in the pathological processes of aging and Alzheimer's disease.
• Targeting senescent microglia presents a promising therapeutic avenue for combating neurodegenerative diseases.
• Further research into microglial senescence could unlock novel treatment strategies for AD and other age-related brain disorders.