Researchers at the University of Rochester Medical Center point to a newly discovered system, which processes and removes waste in the brain, as a possible key to treating neurological disorders such as Alzheimer’s disease.
Modern scientists are beginning to build on the late-1800s understanding of the “blood-brain barrier” with new incoming knowledge of the brain’s dynamics for removing waste, recently dubbed the glymphatic system. The lymphatic system, a circulatory network of organs and vessels, removes waste materials from the rest of the body, but does not extend to the brain. Scientists began to postulate about how the brain kept house, one of the main issues being that there is no trace of any such system within brain tissue samples. But new technology known as two-photon microscopy allowed scientists to delve deeper into the living brain for study. Coupling the new tech with mice brains, Dr. Maiken Nedergaard, co-director of the URMC for Transitional Medicine, and her colleagues were able to observe and document the extensive waste system of the brain.
The brain is surrounded by a membrane, called the arachnoid, that is flushed with cerebral spinal fluid (CSF) which flows through the brain on the same pathways as the arteries reaching the brain. CSF is drawn into the brain tissue through a system of conduits controlled by glia, support cells. CSF is moved through the brain at high speeds, picking up excess proteins and waste products along the way. The fluid and waste are channeled into a system which parallels veins and transports the byproducts from the brain, down the spinal column, and to the liver where everything is ultimately broken down. With this discovery, scientists can delve into the research regarding how to apply this knowledge in the treatment of neurological disorders. This find may prove especially beneficial in the case of Alzheimer’s, a disease whose hallmark is the build-up of beta amyloid plaques. Further research would test whether manipulating glia to ramp up waste removal would better prevent the build-up of excess proteins such as beta amyloid.
1) University of Rochester Medical Center (2013, June 27). Brain’s ‘garbage truck’ may hold key to treating Alzheimer’s and other disorders. ScienceDaily. Retrieved July 1, 2013, from http://www.sciencedaily.com/releases/2013/06/130627142402.htm
By Lauren Horne