A few neurons in the brain undergo a lot of stress to die prematurely and that could lead to Parkinson's disease, a study said.

The dopamine-releasing neurons in the brain lead a lifestyle that requires lots of energy, generating stress that could harm the neurons. The death of these neurons in the region called the substantia nigra causes Parkinson's disease.

"Why this small group of neurons dies in Parkinson's disease is the core question we struggled with," says lead author D. James Surmeier, the Nathan Smith Davis Professor and chair of physiology at Northwestern University Feinberg School of Medicine. "Our research provides a potential answer by showing this small group of neurons uses a metabolically expensive strategy to do its job. This 'lifestyle' choice stresses the neurons' mitochondria and elevates the production of superoxide and free radicals – molecules closely linked to aging, cellular dysfunction and death."

Researchers say a drug that is already approved for human use can control the stress of the neurons. The drug isradipine prevents calcium entry and reduces the stress in the dopamine-releasing neurons.

Parkinson's disease is the second most common neurodegenerative disease in the United States, with over one million patients, second only to Alzheimer's disease. "By lowering their metabolic stress level, we should be able to make dopamine-releasing neurons live longer and delay the onset of Parkinson's disease," Surmeier said. "For individuals diagnosed with Parkinson's disease, the hope is that this drug can slow disease progression, giving symptomatic therapies a broader window in which to work."

The study done on Mice is being published in Nature.