Japanese research using induced pluripotent stem (iPS) cell technology has brought new hope to Parkinson’s disease patients with the discovery that an existing drug for high blood pressure could also be effective on their condition.

The findings were published in U.S. science journal Stem Cell Reports on Oct. 18.

The joint research team included a group from Keio University led by Hideyuki Okano, a professor at the Department of Physiology at the university’s Graduate School of Medicine, and leading pharmaceutical manufacturer Eisai Co.

Parkinson’s disease is caused by a reduction of nerve cells that produce dopamine, which functions as a neurotransmitter in the brain, leading to debilitating symptoms such as tremors, loss of balance and extreme stiffness in the limbs.

An effective treatment for the disease has remained elusive to date. There are an estimated 160,000 sufferers in Japan.

The researchers reproduced the conditions of sufferers by creating iPS cells from cells harvested from two patients of different types of Parkinson’s disease that both run in the family. The researchers then tested 1,165 different drugs, leading to the discovery that benidipine hydrochloride can effectively preserve nerve cells.

About 90 percent of Parkinson’s patients suffer from the sporadic category of the disease that appears with no family history, the research team said. It is difficult to figure out how that category of the disease develops because a wide variety of factors are thought to play a part.

If the mechanism behind the development of the Parkinson’s disease category that runs in the family can be worked out, and drugs that can treat them are discovered, it could lead to the development of treatments for the sporadic types of the intractable disease, too, according to a joint announcement made by Keio University and Eisai.

Okano also led another research team that discovered that amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease, can be treated with ropinirole hydrochloride, an existing drug used for Parkinson’s disease.

That finding was announced by Okano at a regenerative medicine gathering held in Tokyo on Oct. 13.