MicroRNAs as Biomarkers for Parkinson's Disease; A Comparison of CSF and Blood

Objective/Rationale:
We, and many other groups, hypothesize that miRNAs have the potential to be selective and sensitive diagnostic indicators for Parkinson’s disease. The focus of this project is to compare miRNA signatures detected in cerebrospinal fluid with serum from blood. Blood is the least invasive biofluid to obtain, but CSF bathes the central nervous system, potentially reflecting the most dynamic changes in miRNA expression. The data acquired here can be a guide for the future collection of samples.

Project Description:
Purpose: To identify, in CSF and serum, a measurable and consistent change in miRNA expression that can differentiate between people with Parkinson’s, Alzheimer’s and controls. For all of these experiments we will use matched, from the same individual, serum and CSF samples. We will obtain the following three groups of postmortem samples: PD (n=100 CSF and 100 serum samples), AD (n=100 CSF and 100 serum samples) and control (n=100 CSF and 100 serum samples). Because these samples have been neuropathologically verified, we know the disease status definitively. Each patient contributes one serum and one CSF sample, reducing variability between the samples and allowing us to directly compare the strengths of the miRNA signatures generated from each biofluid. miRNAs will be measured through microarrays and sequencing.

Relevance to Diagnosis/Treatment of Parkinson’s Disease:
There has been tremendous effort by the field to find biomarkers and physiological tests that accurately diagnose PD. There is still no conclusive diagnostic test. The goal of this proposal is to test the utility of using a miRNA signature to selectively diagnose and track Parkinson’s disease. By the completion of this study, we will know if CSF or blood contains a better diagnostic miRNA signature for differentiation of two neurodegenerative diseases of the brain, AD and PD.

Anticipated Outcome:
These data will demonstrate how well a miRNA signature differentiates between Parkinson’s disease, Alzheimer’s disease and neuropathologically normal controls. In addition, we will learn which biofluid has the best discriminatory power, cerebrospinal fluid or serum from blood.