Like airport security barriers that either clear authorized travelers or block unauthorized travelers and their luggage from accessing central operation areas, the blood-brain-barrier (BBB) tightly controls the transport of essential nutrients and energy metabolites into the brain and staves off unwanted substances circulating in the blood stream. Importantly, it's highly organized structure of thin blood vessels and supporting cells is also the major obstacle preventing life-saving drugs from reaching the brain in order to effectively treat cancer, neurodegeneration, and other diseases of the central nervous system. In a number of brain diseases, the BBB can also locally break down, causing neurotoxic substances, blood cells and pathogens to leak into the brain and wreak irreparable havoc.
* This article was originally published here
