Crossing the Blood-Brain Barrier

Florence (Reuters Health) -- Vitamin C could provide a key to unlock the blood-brain barrier, which stops many drugs from getting into the brain where they could potentially treat diseases such as Alzheimer's or epilepsy, according to preliminary findings from researchers in Italy. Dr. Stefano Manfredini and colleagues found that drugs used to treat neurological disorders appear to slip past the blood-brain barrier more easily when a vitamin C molecule is attached.

"Ascorbic acid works like a sort of a shuttle. Theoretically, it could transport onto the brain any compound," Manfredini told Reuters Health.

Potential applications include not only drugs for Alzheimer's, Parkinson's and epilepsy, but also viral infections, including AIDS.

In the past, glucose and amino acid units have already shown an ability to cross the blood-brain barrier, Manfredini explained. "But they do not guarantee a selective target, while the SVCT2 transporter can get directly to the central nervous system."

In the laboratory, the researchers evaluated the effect of adding vitamin C to drugs known to have difficulty crossing the blood-brain barrier -- namely diclophenamic acid, nipecotic acid and kynurenic acid. Adding a vitamin C component to each of these three compounds greatly improved their ability to interact with the SVCT2 transporter, the researchers report in the January issue of the Journal of Medicinal Chemistry.

Manfredini told Reuters Health that further tests and additional animal studies of vitamin C-modified drugs were planned. He has filed a patent for the discovery.

Note: It's important that HIV meds cross the blood brain barrier in order to attack the virus in the central nervous system.

Source: Journal of Medicinal Chemistry, 2002 January.