Senescence in aging and disorders of the central nervous system

Abstract

Aging can be defined as the natural process of accumulating time during the life of an organism. Advancing age correlates with tissue dysfunction, including frailty, malignancies, immobility, and cognitive loss. With increasing age, there is an accumulation of cells that have lost their ability to divide and yet do not undergo cell death, termed senescent cells. These cells, which are characterized by a distinctive proinflammatory phenotype, have been demonstrated to damage surrounding cells, which negatively impact health. Within the brain, senescent cells have been associated with a variety of diseases, including Parkinson’s and Alzheimer’s disease, and maladies where chronic inflammation drives tissue deterioration. Here, we describe the resident cells of the central nervous system (CNS), how they exhibit tendencies toward senescence with age and disease, and discuss tools that will be useful to aid in senescent cell identification and characterization in this tissue.