Neuroinflammatory changes increase the impact of stressors on neuronal function.

In the last few years, several research groups have reported that neuroinflammation is one feature common to several neurodegenerative diseases and that similar, although perhaps less profound, neuroinflammatory changes also occur with age. Age is the greatest risk factor in many neurodegenerative diseases, and the possibility exists that the underlying age-related neuroinflammation may contribute to this increased risk. Several animal models have been used to examine this possibility, and it is now accepted that, under experimental conditions in which microglial activation is up-regulated, responses to stressors are exacerbated. In the present article, these findings are discussed and data are presented from in vitro and in vivo experiments which reveal that responses to Abeta (amyloid beta-peptide) are markedly up-regulated in the presence of LPS (lipopolysaccharide). These, and previous findings, point to a vulnerability associated with inflammation and suggest that, even though inflammation may not be the primary cause of neurodegenerative disease, its treatment may decelerate disease progression.