Immunosenescence of microglia and macrophages: impact on the ageing central nervous system

As we age, the central nervous system (CNS) experiences a decline in both gray and white matter, leading to cognitive impairment. This decline is often worsened by neurological disorders such as Alzheimer's disease and multiple sclerosis. Macrophages and microglia, which are immune cells in the CNS, play a role in these conditions. This article explores how macrophages and microglia age differently and how these differences impact the aging CNS. It suggests that targeting these differences with specific therapies might help rejuvenate these cells and improve neurological repair. The authors propose therapeutic strategies that selectively target these diverse mechanisms may rejuvenate macrophages and microglia for repair in the ageing central nervous system.

• 1
  Macrophages and microglia, two types of immune cells in the brain, age in distinct ways, with macrophages showing diminished pro-inflammatory responses and microglia exhibiting an exaggerated pro-inflammatory response with age.
• 2
  Ageing microglia and macrophages exhibit deficits in phagocytic and chemotactic functions.
• 3
  The mechanisms behind these age-related changes vary, ranging from changes in the environment surrounding the cells to intrinsic changes within the cells themselves, such as genomic instability.