Parkinson's disease risk assessed using new fluorescent probe

Researchers from National University of Singapore (NUS) have developed the first two-photon, small molecule fluorescent probe capable of detecting elevated levels of the Monoamine Oxidase B (MAO-B) enzyme, one characteristic of Parkinson's disease.

MAO enzymes come in two forms, MAO-A and MAO-B, which work together to create a neurotransmitter balance in the brain. In Parkinson's disease, there is an abundance of MAO-B, but not MAO-A, because it is over-activated.

"This suggests that MAO-B activity in peripheral blood cells of a patient might serve as an accessible and economical biomarker to evaluate the potential risk of an individual for this disease," Associate Professor Lim Kah Leong, the study's co-leader, stated in a news release.

Led by Professor Yao Shao Qin from the Department of Chemistry, and Leong, from the National Neuroscience Institute in Singapore, the researchers published their breakthrough findings in the Nature Communications journal.

Preexisting probes are unsuccessful in detecting MAO-B levels accurately, and there is currently no reliable biomarker for Parkinson's disease at any stage except for the expensive and highly specialized dopamine-based PET imaging.

This new method for detection is revolutionary in that the fluorescence label on the probe can find MAO-B via high-resolution imaging techniques in tissues and organs at depths of up to one millimeter. This lets researchers effectively monitor the in-vivo enzymatic activities of MAO-B in patients unlike ever before.

The probe can potentially monitor how Parkinson's disease progresses, and thus aid in the development of effective drug treatment, among other things.

One expert, who conducted a separate study showing that long-term use of MAO-B inhibitor reduces the progression of the disease early on, is optimistic about this technology's future uses.

"The probe may potentially be useful to monitor patient's response to medication," said Associate Professor Louis Tan from the Department of Neurology at the National Neuroscience Institute.