[Bioinformatics analysis of differently expressed microRNAs in anxiety disorder]

OBJECTIVE To identify differentially expressed microRNA (miRNA) in peripheral blood mononuclear cells (PBMCs) of anxiety patients and predict their target genes and function by bioinformatics analysis. METHODS The miRNA expression profiles were determined using an Affymetrix array. To validate the results, real-time quantitative polymerase chain reaction (qRT-PCR) analysis in a larger cohort was employed. The targets of the differentially expressed miRNAs were predicted by Target Scan, miRBD, and DIANA-microT-CDS, and the results were analyzed by gene ontology (GO) and KEGG pathway analysis using FunNet. RESULTS MicroRNA microarray chip analysis has identified 7 miRNAs were detected with significant changes in expression in PBMCs of anxiety patients. qRT-PCR analysis has confirmed that the expression levels of 5 miRNAs (has-miR-4484, has-miR-4505, has-miR-4674, has-miR-501-3p and has-miR-663) were up-regulated. Intersecting the genes by Target Scan, miRBD, and DIANA-microT-CDS has predicted 195 targets. GO analysis showed that biological processes regulated by the predicted target genes have included diverse terms. Some terms, e.g., nervous system development, nerve growth factor receptor signaling pathway, neuron migration, dendrite development, regulation of neuron projection development, midbrain development, regulation of excitatory postsynaptic membrane potential, gliogenesis, dendrite morphogenesis, etc. have direct relationship with the central nervous system and brain functions. Pathway analysis showed that a significant enrichment in several pathways related to neuronal brain functions such as glutamatergic synapse, axon guidance, calcium signaling pathway, MAPK signaling pathway, GnRH signaling pathway, Wnt signaling pathway, gap junction, long-term potentiation and VEGF signaling pathway, etc. Among the five microRNAs, has-miR-4484, has-miR-4505, has-miR-4674 and has-miR-501-3p may have more important regulatory functions. CONCLUSION Five miRNAs (has-miR-4484, has-miR-4505, has-miR-4674, has-miR-501-3p and has-miR-663) are up-regulated in PBMCs of anxiety patients and may be closely involved in the pathogenesis of anxiety disorder.