Microglia as Mediators of the Link Between Psychological Stress and Cognitive Aging

Psychological stress appears to modestly accelerate some measures of aging, though most of the evidence for this correlation comes from animal studies. Evidence points to chronic inflammation, and the immune system in general, as an important factor in this correlation. Separately, chronic inflammation in brain tissue is known to be important in neurodegenerative conditions, and the behavior of innate immune cells known as microglia are of late receiving increased attention in this context. Researchers here join the dots to discuss whether microglia may be a primary link between stress and accelerated aging. The relationship between the central nervous system (CNS) and microglia is lifelong. Microglia originate in the embryonic yolk sac during development and populate the CNS before the blood-brain barrier forms. In the CNS, they constitute a self-renewing population. Although they represent up to 10% of all brain cells, we are only beginning to understand how much brain homeostasis relies on their physiological functions. Often compared to a double-edged sword, microglia hold the potential to exert neuroprotective roles that can also exacerbate neurodegeneration once compromised. Microglia can promote synaptic growth in addition to eliminating synapses that are less active. Synaptic loss, which is considered one of the best pathological correlates of cognitive decline, is a distinctive feature of major depressive disorder (MDD) and cognitive aging. Long-term ...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs