Christine Schwienbacher
Posters-Accepted Abstracts: J Neurol Neurophysiol
Background: MicroRNAs (miRNAs) are small, non-coding RNAs that are endogenously expressed to regulate the expression
of many genes involved in disparate physiological functions and pathologies, including Parkinson’s disease (PD).MiRNAs are
strong and specific gene regulators and therefore promising candidates to be diagnostic markers and potential therapeutic
targets. Suitable biomarkers from easy accessible sources, such as peripheral blood, plasma, and serum,which reflect systemwide
biology, could be used to detect and monitor PD in early stages, even before symptoms appear. To date, only few studies
have assessed the expression of blood miRs related to PD. Although miRshave been intensively investigated as potential
diagnostic markers, currently there is no reliable and clinically validated biomarker for PD.
Objective: The aim of the study was to profile the expression of several candidate miRNAs in peripheral blood mononucleated
cells (PBMCs) from Levodopa (L-dopa) treated and drug-naïve PD patients versus unaffected controls and to interpret the
expression data in a biological context.
Methods:We analyzed RNAs from PBMCs of 36L-dopa-treated, 10 drug-naïve PD patients and unaffected controls matched
by sex and age. We evaluated expression by RT-qPCRand we analyseddata using a two-tailed paired t-test. To detect miRNA
targets, several miRNA resourceswere combined to generate an overall score for each candidate gene using weighted rank
aggregation.
Results: Significant overexpression of miRNAs 103a-3p, 30b-5p, and miR-29a-3p in treated PD patients was observed and
promising candidate target genes for these revealed by an integrated in silico analysis.
Conclusions:We revealed three candidate biomarkers for PD. MiRNAs 30b-5p and 29a-3p replicated a documented deregulation
in PD albeit opposite to published data. For miR-103a-3p we demonstrated for the first time an upregulation in treated PD
patients.Expression studies in patients before and following L-dopa administration are necessary to define the involvement of
L-dopa treatment in the observed deregulation.Our in silico analysis to prioritize targetsof overexpressed miRNAs identified
candidate target genes, including genes related to neurodegeneration and PD. Despite the preliminary character of our study,
the results provide a rationale for further clarifying the role of the identified miRNAs in the pathogenesis of PD and for
validating their diagnostic potential.
