The microRNAs hsa-miR-342 and -494 are upregulated in the brain of BSE-infected macaques

Although transmissible spongiform encephalopathies are thought to be mediated by the pathogenic isoform of the prion protein PrPSc, the molecular mechanism underlying neurodegeneration is poorly understood. MicroRNAs (miRNAs) have been shown to cause or influence the pathogenesis of several diseases, however, they were not linked to prion disorders yet. We have addressed the regulation of miRNAs in BSE-infected macaques as a model for human Creutzfeldt-Jacob disease. Applying miRNA microarrays and quantitative RT-PCR, we found that two miRNAs, hsa-miR-342 and hsa-miR-494, are upregulated in the brain of BSE-infected monkeys. Predictions of potential target genes revealed functional links to other neurodegenerative disorders with protein aggregation, including Alzheimer’s and Huntington’s disease. Differential miRNA analysis may be a powerful tool to identify common pathways in the pathogenesis of neurodegeneration.