News - Hypertension Week of Jan. 25, 2004/ Vol. 3 No. 04

Study: Chemical May Protect Brain Cells from Damage During Stroke

A surprising discovery in mice by Johns Hopkins University researchers could pave the way for new treatments for stroke.

As reported in the January 7 issue of the Journal of Neuroscience, the researchers found that a chemical known as prostaglandin-E2 protects brain cells from damage even though it causes damage in other tissues and is made by an enzyme, COX-2, known to wreak havoc in the brain after injury.

If given within an hour of the stroke, an existing drug called t-PA can prevent extensive damage by dissolving the blood clot that caused the stroke, but a need exists for a treatment that can be given later to stroke victims whose symptoms aren't immediately recognized or who are more than an hour from a hospital.

"Prostaglandins have not previously been implicated in reducing damage from stroke, so our finding provides a completely new strategy for tackling and understanding the condition," said lead researcher Dr. Katrin Andreasson, an assistant professor of neurology and of neuroscience.

Andreasson added that future treatments for stroke might use drugs to block COX-2 and enhance the effects of prostaglandin-E2, providing sort of a double whammy of protection.

The researchers found that prostaglandin-E2 is beneficial in the brain because the stimulation of its receptor increases production of a molecule called cyclic-AMP, which is known to help the brain. Prostaglandin-E2 also has anti-inflammatory effects that may also contribute to its protective abilities in the brain, says Andreasson.

"We think that COX-2 products that increase cyclic-AMP may prove to be protective, like PGE2, while those that lower cyclic-AMP may contribute to COX-2's known negative effects on brain damage from stroke," Andreasson said.

Andreasson said she and her colleagues still need to determine whether stimulating the prostaglandin-E2 receptor hours after a stroke can protect mice from damage.

"If so, pursuing this prostaglandin as a potential clinical target will be of great importance," she added.

Other sources: Johns Hopkins