The Blood-Brain Barrier: A Barrier To Drug Uptake

The brain is one of our most vital organs pertinent to life and all of our bodily functions.  So it is not surprising that we come equipped with a blood-brain barrier to ensure that not everything that enters the bloodstream or the body is able to make it to the brain.  It acts as both a filter and protectant.  The brain possesses epithelial-like tight junctions within its capillary endothelium which is thought to contribute to its ability to provide such a barrier.  It has long been known that the blood-brain barrier prevents the uptake of a large majority of therapeutic agents into the brain, posing a challenge for researchers seeking to treat diseases of the brain such as cancers and other diseases.  There are certain chemical properties that make a compound more likely to cross the blood-brain barrier which are not present in most drugs; however, there are groups of chemists who specialize in optimizing and re-engineering drugs for this exact purpose: to cross the blood brain barrier and successfully carry out their intended function.  This video highlights the physiology of the bood-brain barrier.

Sources: Wikipedia, Journal of Cebral Blood Flow and Metabolism, Johns Hopkins University, Youtube