Microglial Senescence And Epigenetic Reprogramming In Alzheimer’S Disease: An Immunometabolic Perspective
Our brains have dedicated immune cells called microglia, which are crucial for keeping the brain healthy by clearing debris and protecting against damage. However, as we age, and particularly in conditions like Alzheimer’s disease, these vital cells can become “senescent.” This means they essentially grow old and dysfunctional, losing their ability to perform their protective tasks effectively. Instead of clearing harmful substances like the amyloid-beta plaques and tau tangles associated with Alzheimer’s, these senescent microglia can actually start releasing inflammatory chemicals that harm surrounding brain cells.
This shift in microglial behavior is influenced by two key factors. First, there’s “epigenetic reprogramming,” which refers to changes in how genes are turned on or off without altering the underlying DNA sequence. These changes can fundamentally alter a microglial cell’s identity and function, pushing it towards a senescent, pro-inflammatory state. Second, “immunometabolism” plays a critical role. This term describes how immune cells, like microglia, process and use energy. In Alzheimer’s, the energy metabolism of microglia can become dysfunctional, impairing their ability to clear waste and respond appropriately to threats. Understanding how these processes—cellular aging, gene regulation, and energy use—interact within microglia is crucial. By unraveling these complex mechanisms, scientists hope to develop new strategies to reprogram these cells, restore their protective functions, and ultimately slow or prevent the progression of Alzheimer’s disease.
Source: link to paper