As is well known, the blood-brain barrier is a strict checkpoint that prevents variety of drugs from reaching the brain. At the Massachusetts Eye and Ear/Harvard Medical School and Boston University researchers have developed a technique that enabled them to deliver glial derived neurotrophic factor (GDNF), a large protein being tested for treatment of Parkinson’s disease, into the brains of mice. Currently GDNF is delivered by direct injection into the brain, a dangerous procedure that often leads to complications. The new technique relies on nasal mucosal grafting that is normally performed after minimally invasive brain tumor procedures to close the access route.
Nasal mucosa is considerably more lenient in letting molecules through than the blood-brain barrier, and so can act as a secret passage for drug delivery. When the researchers used this access point to deliver GDNF, they showed that the protein had an equivalent effect when compared to being delivered by a direct injection.