Researchers from Rush University Medical Center suggest that the levels of a particular brain protein called alpha-synuclein are significantly lower than normal in the spinal fluid collected from Parkinson’s disease patients experiencing postural instability and gait difficulty.

“This report is an important contribution in our efforts to understand and quantify Parkinson’s biology to accelerate drug development,” says Mark Frasier, PhD, senior vice president of research programs at the Michael J. Fox Foundation, which provided funding for the study, and an author of the study, published recently in Movement Disorders.

The cross-sectional, observational study collected data and body fluid samples from 120 people with moderately advanced Parkinson’s disease and 100 control volunteers across eight academic sites in the US at two points over 2 weeks, according to a media release from Rush University Medical Center.

Dr. Jennifer G. Goldman, a movement disorders neurologist at Rush University Medical Center and the study’s lead author, has profiled the Parkinson’s-associated protein levels in these biofluids and their relationships to clinical features of the disease. The study found that levels of alpha-synuclein were lower in cerebrospinal fluid from Parkinson’s patients with certain motor function impairments—specifically in those who had more problems with balance and walking compared to those with more tremor.

In addition, levels of beta-amyloid, known for its association with Alzheimer’s disease, were lower in those with Parkinson’s and related to worse scores on a memory recall in Parkinson’s as measured on a rest of thinking and memory given to study participants.

The study also showed that alpha-synuclein levels in plasma and saliva did not differ between people with Parkinson’s and control volunteers, and alpha-synuclein did not significantly correlate among other biological fluids, the release explains.

“These are important insights for the ongoing pursuit of accessible biomarker tests to diagnose and track the disease,” Goldman says. “For example, people with Parkinson’s and lower beta-amyloid may be more likely to develop memory problems and therefore would benefit more from a cognitive therapy. Enrolling this population in trials can help us see a treatment effect more clearly than testing the therapy on people who will not have this symptom.”

Next steps include validation of these findings in the Parkinson’s Progression Markers Initiative (PPMI), a biomarkers study sponsored by the Michael J. Fox Foundation that is following more than 1,500 people with Parkinson’s or risk factors and control volunteers over at least 5 years. Additionally, trials ongoing or launching in the near future could use alpha-synuclein or beta-amyloid levels as exploratory biomarkers in motor symptom or cognition drug trials, respectively, per the release.

[Source(s0): Rush University Medical Center, Science Daily]