Skin may conceal a viable Parkinson's biomarker

Spotting early-stage Parkinson's disease is a major goal because it could be key to developing treatments that stop, or at least slow, its progression. But where can you reliably find the best biomarker to accomplish this? It might be just under the skin, researchers from Beth Israel Deaconess Medical Center have concluded.

Their work, scheduled for the Oct. 29 print edition of the journal Neurology and published in the interim online, involved the detection of alpha-synuclein in the skin of Parkinson's patients. Typically found throughout the nervous system, alpha-synuclein also is found in Lewy bodies, clumps of protein that experts believe are a major sign of Parkinson's progression.

For their study, the researchers looked at 20 Parkinson's disease patients and 14 control subjects. They found Parkinson's patients had more alpha-synuclein in the cutaneous nerves supplying sweat glands and pilomotor muscles. Also, patients with more advanced Parkinson's disease and worsening autonomic function had much greater amounts of alpha synuclein deposits in the nerves supplying the skin's autonomic structures.

"There is a strong and unmet need for a biomarker for Parkinson's disease," Dr. Roy Freeman, director of BIDMC's Autonomic and Peripheral Nerve Laboratory and the study's senior author, said in a statement. "Alpha-synuclein deposition within the skin has the potential to provide a safe, accessible and repeatable biomarker."

The quest to enable early-stage Parkinson's diagnostics continues on a number of fronts. Among them: the Perelman School of Medicine at the University of Pennsylvania recently developed a test, based on the evaluation of spinal fluid, that establishes 5 potentially viable biomarkers. The University of Alabama believes a reduced sense of smell might be a workable Parkinson's disease biomarker. A global study, meanwhile, is underway to evaluate potential Parkinson's disease biomarkers, including rapid eye movement sleep behavior disorder or a mutation in the LRRK2 gene.

Meanwhile, the Beth Israel Deaconess Medical Center team is plowing ahead with its own work. More research is needed on a wider pool of patients to validate their findings. And they are broadening their study. Next, they'll explore, in part, whether alpha-synuclein can be found in cutaneous nerves of patients at risk for Parkinson's.

Grants from the National Institutes of Health, the Langer Family Foundation and the RJG Foundation helped support the study.

- read the release
- here's the journal abstract