Cellular and Extracellular microRNA Dysregulation in LRRK2-Linked Parkinson's Disease
The discovery of cell-free micro-RNAs in body fluids has made them a promising biomarker target in the field of neurodegenerative diseases. Although they have been reported to be differentially expressed in biofluids and tissue from sporadic Parkinson's disease patients, it remains unclear whether similar observations can be made in patients with genetic forms of the disease. Since induced pluripotent stem cell derived neurons represent a widely used research model for both sporadic and familial Parkinson's disease, we sought to assess the usability of this model for the identification of differentially expressed cell-free micro-RNAs in the context of the Parkinson's disease related LRRK2 G2019S mutation in a proof-of-concept study. We isolated extracellular vesicles carrying cell-free RNA from patient-derived induced pluripotent stem cell lines carrying the LRRK2 G2019S mutation and their gene corrected isogenic controls. After generation of small-RNA libraries and differential expression analysis, we validated fourteen micro-RNAs in an independent batch of cell-free and cellular RNA via RT-qPCR. Finally, we selected eleven differentially expressed micro-RNAs from our cell culture experiments and quantified their expression levels in cerebrospinal fluid derived from two LRRK2 G2019S patients and two healthy controls. Overall design: Isolated extracellular vesicles carrying cell-free RNA from patient-derived induced pluripotent stem cell lines carrying the LRRK2 G2019S mutation and their gene corrected isogenic controls.