A research group led by Koji Sugada, a full-time lecturer at Keio University, discovered the mechanism necessary for the brain to form a barrier function to prevent foreign body invasion.
About 15% of the blood that flows through the body is in the brain, carrying nutrients and carrying out unwanted substances.Therefore, in order to maintain the delicate functions of nerve cells and the brain, it is necessary to have a mechanism to prevent harmful substances from leaking from blood vessels to the brain and a mechanism to quickly push unnecessary substances back into the blood.This barrier function of intracerebral capillaries is called the blood-brain barrier, and its function decreases due to inflammation of the brain, brain tumors, and aging.However, many of the mechanisms of blood-brain barrier formation and function maintenance have not been elucidated.
This time, we worked on elucidating this mechanism using the brain of Drosophila, which is widely used in the fields of medicine and biology, and its barrier function as an experimental model.It is said that humans and Drosophila have much in common in the mechanism that strictly limits the contact between the brain and blood (body fluid in flies) and the genes that control it.
As a result of research, we found that proteolytic enzymes belonging to the group "matrix metalloproteinase (Mmp)" are indispensable for the correct formation of the mechanism of the blood-brain barrier with barrier function.Until now, this enzyme has been regarded as a "breaker" that decomposes collagen around blood vessels and reduces the function of the blood-brain barrier due to inflammation of the brain.However, this time, it was found that this degrading enzyme and its function, while having a function of disrupting the function of the blood-brain barrier, are also indispensable for its formation.
The results of this research include elucidation of the molecular mechanism in the formation of the blood-brain barrier, future treatment of brain diseases, nerve regenerative medicine, and the barrier function of the blood-brain barrier when inducing vascular endothelial cells from iPS cells and the like. It is expected to contribute to the improvement of.
Paper information:[IScience] Degradation of extracellular matrix by Matrix metalloproteinase 2 is essential for the establishment of the blood-brain barrier in Drosophila
