October 10, 2008, 11:03 am
A daily dose of the herbal remedy gingko biloba may help prevent brain damage after stroke, new research suggests.
The findings, published online in the medical journal Stroke, have been shown only in mice, but researchers say the studies support theories that ginkgo biloba may be a useful treatment for stroke patients.
“It’s still a large leap from rodent brains to human brains, but these results strongly suggest that further research into the protective effects of ginkgo is warranted,” said lead researcher Sylvain Doré, an associate professor in the Johns Hopkins department of anesthesiology and critical care medicine, in a press release. “If further work confirms what we’ve seen, we could theoretically recommend a daily regimen of ginkgo to people at high risk of stroke as a preventive measure against brain damage.”
In the series of mouse studies, scientists induced stroke in animals, including some that had previously been given various doses of ginkgo biloba. Normal mice that had been pretreated with the herb had 51 percent less neurological dysfunction than untreated mice, and areas of brain damage were reduced by 48 percent in the ginkgo group.
“Our results suggest that some element or elements in ginkgo actually protect brain cells during stroke,” Dr. Doré said.
About 700,000 people experience a stroke in the United States annually. Nearly nine out of 10 stroke sufferers experience ischemic stroke, which is caused by a blocked artery in the brain. The stroke itself can cause brain damage by depriving brain cells of blood. But toxic oxygen molecules, known as free radicals, also can cause additional damage after the clot is cleared.
Ginkgo biloba, which comes from a Chinese tree with fan-shaped leaves, may work to prevent further brain damage because it increases levels of an enzyme that eliminates free radicals around the stroke site in the brain.
“Ginkgo has long been touted for its positive effects on the brain and is even prescribed in Europe and Asia for memory loss,” Dr. Doré said. “Now we have a possible understanding for how ginkgo actually works to protect neurons from damage.”
Patients should talk to their doctor before taking gingko. One concern is that gingko thins blood, and patients at risk for strokes and seizures are warned against taking it. Ginkgo biloba should be discontinued at least 36 hours before surgery due to the risk of increased bleeding. Patients with bleeding or clotting disorders, or those who use warfarin, insulin and several other drugs, should also not take ginkgo.
http://well.blogs.nytimes.com/2008/10/10/ginkgo-holds-promise-for-stroke-patients/
