Abstract
Alzheimer’s disease (AD) and related dementias are closely associated with alterations in microglial states. These microglial changes occur in response to amyloid-β (Aβ) accumulation and aberrant tau phosphorylation and can either protect against or exacerbate AD progression, depending on factors such as disease stage, genetic background, and environmental influences. This review focuses on recent advances in understanding the protective functions and features of microglia during the early stages of AD, while highlighting the outstanding questions regarding how these protective states deteriorate and become dysfunctional as the disease progresses. Interestingly, epidemiological studies have suggested an inverse relationship between AD and cancer incidence, and in this context we provide a comparative analysis of microglial phenotypes in AD and cancer to speculate how insights from anti-tumor microglia may inspire new strategies for reprogramming microglia to combat AD and related dementias.
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