Microglia derived from aging mice exhibit an altered inflammatory profile
Article first published online: 3 JAN 2007
Copyright © 2007 Wiley-Liss, Inc.
Volume 55, Issue 4, pages 412–424, March 2007
How to Cite
Sierra, A., Gottfried-Blackmore, A. C., McEwen, B. S. and Bulloch, K. (2007), Microglia derived from aging mice exhibit an altered inflammatory profile. Glia, 55: 412–424. doi: 10.1002/glia.20468
- Issue published online: 11 JAN 2007
- Article first published online: 3 JAN 2007
- Manuscript Accepted: 15 NOV 2006
- Manuscript Revised: 13 NOV 2006
- Manuscript Received: 15 AUG 2006
- NIA. Grant Number: AG16765
- Moody Foundation
- brain inflammation;
- flow cytometry;
Microglia play a critical role in neurodegenerative diseases and in the brain aging process. Yet, little is known about the functional dynamics of microglia during aging. Thus, using young and aging transgenic mice expressing enhanced-green fluorescent protein (EGFP) under the promoter of the c-fms gene for macrophage-colony stimulating factor receptor, we evaluated invivo-induced inflammatory responses of EGFP-expressing microglia sorted by flow cytometry. Aging microglia were characterized by the presence of lipofuscin granules, decreased processes complexity, altered granularity, and increased mRNA expression of both pro-inflammatory (TNFα, IL-1β, IL-6) and anti-inflammatory (IL-10, TGFβ1) cytokines. Following lipopolysaccharide (LPS) challenge (1 mg/kg, 3 h), aging microglia exhibit increased basal expression of TNFα, IL-1β, IL-6, and IL-10. Yet, the fold-over-basal LPS response remained constant across age, implying that the inflammatory machinery in aging microglia is functional and adjusted to the basal state. Gender differences were not overall observed across the treatments (age, LPS). The low but sustained production of pro-inflammatory cytokines by aging microglia may have a profound impact in the brain aging process. © 2007 Wiley-Liss, Inc.