Senescent Astrocytes in the Aging of the Brain

Cellular senescence in the supporting cells of the brain is increasingly implicated in the onset and progression of neurodegenerative conditions. Senescent cells accumulate with age, as the immune system becomes less competent and falters in their timely removal. These errant cells secrete pro-inflammatory factors that are disruptive of tissue structure and function, contributing to the neuroinflammation that is characteristic of age-related cognitive decline and dementia. We can hope that senolytic treatments capable of passing the blood-brain barrier will help to prevent and treat many forms of neurodegenerative disease but reducing the burden of cellular senescence, both in the brain, and elsewhere in the body. For many decades after their discovery, astrocytes, the abundant glial cells of the brain, were believed to work as a glue, supporting the structure and metabolic functions of neurons. A revolution that started over 30 years ago revealed many additional functions of these cells, including neurogenesis, gliosecretion, glutamate homeostasis, assembly and function of synapses, neuronal metabolism with energy production, and others. These properties have been confirmed, limited however, to proliferating astrocytes. During their aging or following severe brain stress lesions, proliferating astrocytes are converted into their no-longer-proliferating, senescent forms, similar in their morphology but profoundly modified in their functions. The changed specif...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs