Could estrogen help treat Parkinson's?

Researchers already knew that men and postmenopausal women have a higher risk of developing Parkinson's disease than premenopausal women. Now, a recent study in mice concludes that estrogen may be responsible. The authors also hope that estrogen might form the basis of future treatments.

Parkinson's disease is a neurodegenerative condition. According to the National Institutes of Health (NIH), about 50,000 people in the United States receive a diagnosis of Parkinson's every year.

Today, approximately 500,000 people in the U.S. are living with Parkinson's disease.

One of the primary risk factors is advanced age, so as the population grows ever older, the number of Parkinson's cases is likely to rise.

Understanding how and why the condition develops is paramount because there is currently no cure.

Alpha-synuclein and Parkinson's

The primary driver of Parkinson's is a mutated, shorter-than-normal version of a protein called alpha-synuclein.

This protein congregates inside the dopamine-producing neurons that are responsible for coordinating movements and forms structures called Lewy bodies and neurites.

Over time, the buildup of alpha-synuclein prevents brain cells from functioning and, eventually, they die. The resultant loss of neurons causes the movement problems that are characteristic of Parkinson's, such as tremor and rigidity.

Although scientists have been studying Parkinson's for decades, there are still many gaps in their knowledge.

One of these unanswered questions is why Parkinson's occurs earlier in men and is more common in postmenopausal women.

Recently, a group of researchers from Harvard Medical School in Boston, MA, decided to take a close look at the role of estrogen. They published their findings in the journal JNeurosci.

Why estrogen?

Earlier studies identified a relationship between estrogen and Parkinson's disease.

For instance, the authors of a 2004 study investigating Parkinson's risk and its relationship with "reproductive characteristics" concluded that there was "[a]n association between factors reducing estrogen stimulation during life and [Parkinson's disease]."

Other findings over the years have hinted that estrogen might protect the brain. One studyrecruited women who had undergone an oophorectomy, which is the surgical removal of one or both ovaries, the primary source of estrogen in women.

They found that these women had an increased risk of cognitive decline and Parkinson's disease.

Other studies have found evidence that estrogen might help reduce symptoms of Parkinson's. One small-scale study, for example, found that low doses of estrogen reduced motor symptoms in postmenopausal women with Parkinson's.

Although estrogen's neuroprotective powers are becoming better established, exactly how estrogen might protect against Parkinson's disease is still a mystery.

Source: Medical News Today