Reviewing the Role of the Glymphatic System in Brain Aging

That the brain has a lymphatic system is a comparatively recent realization. It coincides with another recent realization that perhaps drainage of fluid from the brain is important in maintaining brain health, carrying away molecular waste that would otherwise accumulate to cause pathology. Common age-related neurodegenerative diseases are characterized by rising inflammation and increasing presence of protein aggregates and other molecular waste in the brain, and it is now known that drainage pathways from the brain to the body are impaired with age. It remains to be seen how well restored drainage performs as a basis for therapy, though Leucadia Therapeutics nears human clinical trials of their implant to restore cerebrospinal fluid drainage through the cribriform plate, a different pathway from the glymphatic system that is more relevant to the onset of Alzheimer's disease. It was traditionally believed that the lymphatic system didn't exist in the central nervous system. Thus, cell debris, potential neurotoxic proteins, and other metabolites with large molecular weight were considered to be removed in a different clearance pathway than brain vasculature. In 2012, the researchers found that cerebrospinal fluid (CSF) can enter brain parenchyma and exchange with brain interstitial fluid (ISF) in the presence of aquaporin-4 (AQP4) on astrocytes. Likewise, when the mixed fluid was drained from the brain, Amyloid-β (Aβ) was transported along with the outflow. Since t...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs