Abstract

Parkinson's disease (PD) is a neurodegenerative disorder with no cure. The pathological hallmark of PD is the aggregation of alpha synuclein (aSyn) proteins in the neurons in the form of Lewy neurites and Lewy Bodies. Thus, developing new drug therapies that block or reduce aSyn aggregation could potentially stop or slow the disease progression. MicroRNAs (miRNAs) are small, conserved RNAs that regulate gene expression and involve in many important biological processes. miRNA-34b and miRNA-34c are predicted targets for aSyn and are shown to be down-regulated in PD brain specimens. Here, we aimed to evaluate the expression of miRNA-34b/c in a differentiated SH-SY5Y cell line induced with rotenone that replicates PD phenotype. First, we defined the cell growth curves of undifferentiated and differentiated SH-SY5Y to determine the best time range to evaluate the effects of drugs or biological compounds. Cell viability was determined with trypan blue. miR-34b/c and aSyn gene expression were evaluated using quantitative real time PCR (qRT-PCR). We found miR-34b/c expression downregulated in rotenone treated cells when compared with non-treated control. However, aSyn expression was not upregulated in rotenone treated cells as expected. One possible explanation is that aSyn formed aggregates, deterring aSyn qRT-PCR probe to bind efficiently for its gene expression study. We plan to perform Western blot and/or immunohistochemistry to evaluate aSyn protein expression instead. Once the feasibility of this study is established, we can apply miRNA mimics or inhibitors to this cell model to investigate their effects on aSyn protein aggregation.