Vitamin C Powers Up Pills
Supplement helps drugs for brain disease reach their target, study shows
FRIDAY, Feb. 1, 2002 (HealthDayNews) -- Adding vitamin C to medications for brain disorders may lead to safer, more effective treatments for such diseases such Alzheimer's, Parkinson's and epilepsy.
That's the hope of a group of Italian researchers, who have just published the results of a study they say proves the premise could work.
"The improvements would be in the development of new pharmacologic approaches," says lead author Stefano Manfredini, a professor of pharmaceutical chemistry at the University of Ferrara in Italy.
For a drug to treat a brain disorder, it must reach the central nervous system. That means it has to cross a natural blood-brain barrier, a kind of safety wall that helps regulate the movement of chemicals throughout brain tissue.
Currently, experts say, most drugs used for brain disorders accomplish this quite easily.
However, there are other drugs -- ones that could be more potent -- that can't get into the brain easily. They would have to be given in such high doses that the toxic effects would outweigh the benefits. This, Manfredini says, is where the vitamin C molecules could help.
Because vitamin C has its own transport system into the brain, attaching the drugs to the vitamin C molecules is a bit like sending a pharmacological limousine to drive the drugs directly to their destination. Zipping right past the blood-brain barrier, they can immediately go to work in the exact spot where they are needed, he explains.
For Dr. Steven Ferris, the concept is smart and could result in a wider range of treatment options.
"I can see some potential in using this system to develop new medications that, right now, are not even being considered, either because the required dosing is too high or not enough of the medication can get into the brain," says Ferris, director of the Alzheimer's Center at New York University Medical Center.
Because vitamin C isn't toxic, and might even be good for the brain, the combination could quite powerful -- if future studies pan out.
"And that's a big 'if,'" says Ferris, who points out it's a long way between laboratory research and human use.
The study, which appears in the current Journal of Medicinal Chemistry, involved three different compounds used to treat a range of brain disorders. However, some have trouble gaining entry to brain tissue.
To test the compounds, the researchers added vitamin C to human epithelial cells -- which are rich in the factors that help transport vitamin C. In fact, these cells contain the same transport cells that are found in the brain, and they help bring vitamin C molecules across the blood-brain barrier, Manfredini explains.
To test their theory on an animal model, Manfredini's group used a group of mice that were chemically induced to have convulsions.
First, they injected the mice with a medication that might stop the convulsions if it could get into the brain. By itself, it had no effect.
However, when a modified version of the drug was injected -- one in which the medication was attached to vitamin C molecules -- convulsions were delayed.
"We just made a speculation based on our previous knowledge of vitamin C and selective delivery of drugs, and we may say that we were pleasantly surprised [with the results]," says Manfredini.
Ferris believes the study has merit, and at least some indications for future use.
"Right now, there is a lot of interest in developing novel, different drug delivery systems -- more effective ways of getting medication into the body," he says.
More importantly, the better the transport system, the less medication that is needed to get the desired effect. Often, the less drug you need, the fewer side effects you have, Ferris says.
"Vitamin C may be one way to accomplish this," he says.
What To Do
For more information on the latest treatments for brain disorders, visit The National Institute of Mental Health.
To learn more about Alzheimer's disease, go to the The National Institutes of Health. For more on epilepsy, check out the Epilepsy Foundation. To discover more about Parkinson's disease, visit the Parkinson's Disease Foundation.