Hypertension Drug Reverses Death of Cells

Purdue University researchers have identified a drug commonly used to treat hypertension that may also reverse damage from spinal cord injuries, cancer and Parkinson's disease.

A research team led by Riyi Shi (REE-yee SHEE) and Richard Borgens found that hydralazine, a medication that relaxes veins and arteries, may be an antidote for acrolein, a deadly toxin that is produced after a nerve cell is injured.

New findings based on research at the cellular level are detailed in two studies published in the Journal of Neuroscience Monday, April 17. In the first article, researchers examine how acrolein attacks and kills cells. In the second article, they demonstrate that cell death caused by acrolein (a-KRO-le-an), a byproduct of an injury, can be reversed when hydralazine is administered.

"This is probably the most important fundamental discovery we have made at the Center for Paralysis Research because we are saving nerve cells from death," said Borgens, Mari Hulman George Professor of Applied Neurology in the School of Veterinary Medicine and founder of the paralysis research center where the research was conducted.

"Initially we may use this discovery for spinal cord injury and stroke, but we can expect further studies will look at how it works against a whole spectrum of injury and disease," he said.

Purdue researchers collected data on acrolein from cell cultures and found that the potent toxin can destroy entire groups of cells in less than 12 hours. But they also determined that the cells would survive if the toxin were treated with hydralazine that acts very much like an antidote, Borgens said.

"We analyzed other natural toxins as well, and our success has been remarkable," Borgens said. "We found that more than 80 percent of the cells can be saved with hydralazine."

Acrolein stays in the body for days and is responsible for secondary damage that keeps injured cells from healing. The idea to use hydralazine against acrolein is a logical extension of research on the toxin, such as the use of a beta blocker against high blood pressure or chicken soup for a cold, Shi said.

"Acrolein is one of the causes of free radicals that are known to damage cells, so it makes sense to stop them from ever being produced," said Shi, who is associate professor of basic medical science in Purdue's School of Veterinary Medicine. "With hydralazine, we are attacking the root of the problem rather than the symptom."

Acrolein is a type of cell toxin called an aldehyde; and the drug, hydralazine, is effective because it has the ability to trap aldehydes and stick to them. Once hydralazine binds to the aldehyde, the toxin is neutralized, deactivated and secreted, Shi said.

The Purdue researchers started looking at alternative methods to save cells because other studies that had tried to use antioxidants to deactivate free radical molecules had failed in human clinical trials in traumatic brain injuries, strokes and spinal cord injuries.