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Open Access 01-12-2010 | Review

Microglia in the aging brain: relevance to neurodegeneration

Authors: Xiao-Guang Luo, Jian-Qing Ding, Sheng-Di Chen

Published in: Molecular Neurodegeneration | Issue 1/2010

Abstract

Microglia cells are the brain counterpart of macrophages and function as the first defense in the brain. Although they are neuroprotective in the young brain, microglia cells may be primed to react abnormally to stimuli in the aged brain and to become neurotoxic and destructive during neurodegeneration. Aging-induced immune senescence occurs in the brain as age-associated microglia senescence, which renders microglia to function abnormally and may eventually promote neurodegeneration. Microglia senescence is manifested by both morphological changes and alterations in immunophenotypic expression and inflammatory profile. These changes are likely caused by microinvironmental factors, but intrinsic factors cannot yet be completely excluded. Microglia senescence appears to underlie the switching of microglia from neuroprotective in the young brain to neurotoxic in the aged brain. The hypothesis of microglia senescence during aging offers a novel perspective on their roles in aging-related neurodegeneration. In Parkinson's disease and Alzheimer's disease, over-activation of microglia may play an active role in the pathogenesis because microglia senescence primes them to be neurotoxic during the development of the diseases.

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Title: Microglia in the aging brain: relevance to neurodegeneration
Authors: Xiao-Guang Luo
Jian-Qing Ding
Sheng-Di Chen
Publication date: 01-12-2010
Publisher: BioMed Central
Published in: Molecular Neurodegeneration / Issue 1/2010
Electronic ISSN: 1750-1326
DOI: https://doi.org/10.1186/1750-1326-5-12

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Microglia in the aging brain: relevance to neurodegeneration

Abstract

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

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