Circ_0000029 Interacts with the miR-576-5p/KCNA1 Axis to Hamper the Development of Pediatric Asthma in an Asthma-Like in vitro Assessment.

OBJECTIVE: Numerous circular RNAs (circRNAs) have been verified to execute crucial roles in "asthma-like" progression of the airway smooth muscle cells (ASMCs). The present study aimed to scrutinize the function and mechanism of circ_0000029 in pediatric asthma etiology in vitro. METHODS: A cell model of asthma was developed using ASMCs induced by platelet-derived growth factor BB (PDGF-BB). Western blotting and qRT-PCR were performed to determine the expression levels of circ_0000029, miR-576-5p, and KCNA1 in PDGF-BB-treated ASMCs. Dual-luciferase reporter, RNA-binding protein immunoprecipitation, and RNA pull-down experiments were conducted to validate targeting relationships. CCK-8 and Transwell assays were performed to evaluate the proliferative and migratory potential of ASMCs. The rate of apoptosis was analyzed using flow cytometry. RESULTS: Pronounced circ_0000029 and KCNA1 downregulation and high levels of miR-576-5p were observed in PDGF-BB-treated ASMCs. Circ_0000029 targets miR-576-5p to regulate KCNA1 expression. The loss of KCNA1 and upregulation of miR-576-5p dramatically impeded apoptosis but promoted ASMC migration and proliferation. Ectopic expression of circ_0000029 manifested the opposite outcome among ASMCs. Furthermore, KCNA1 deficiency and miR-576-5p upregulation counteracted the effects of circ_0000029 overexpression on ASMCs. CONCLUSIONS: Circ_0000029 represses the abnormal migration and growth of ASMCs by mediating miR-576-5p and KCNA1 expression levels. This suggests that the regulatory axis circ_0000029/miR-576-5p/KCNA1 is a potential target for pediatric asthma treatment.

iTRAQ-based high-throughput proteomics analysis reveals alterations of plasma proteins in patients infected with human bocavirus.

Human bocavirus (HBoV) is a member of the genus Bocavirus, family Parvoviridae, and subfamily Parvovirus and was first identified in nasopharyngeal aspirates of Swedish children with acute respiratory tract infection (ARTI) in 2005. It is the causative agent of nasopharyngeal aspirate disease and death in children. The HboV genomic structure is a linear single-stranded DNA (ssDNA). Its clinical pathogenic characteristics have been extensively studied, however, at present the molecular mechanism underlying the pathogenesis of HBoV infection is not completely clear. In this study, a total of 293 differentially expressed proteins (DEPs) between ARTI cases and healthy plasma samples were characterized using isobaric tags for relative and absolute quantitation (iTRAQ)-coupled bioinformatics analysis, among which 148 were up-regulated and 135 were down-regulated. Gene Ontology (GO) and Cluster of Orthologous Groups of proteins (COG) annotated an enrichment of DEPs in complement activation and biological processes like immunity, inflammation, signal transduction, substance synthesis, and metabolism. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis enriched DEPs mainly in the Wnt signaling pathway (ko04310), PPAR signaling pathway (ko03320), intestinal immune network for IgA production (ko04672), complement and coagulation cascades (ko04610), Toll-like receptor signaling pathway (ko04620) and B cell receptor signaling pathway (ko04662). Further, expression levels of three candidate proteins (upregulated PPP2R1A and CUL1, and downregulated CETP) were validated using western blotting. Our investigation is the first analysis of the proteomic profile of HBoV-infected ARTI cases using the iTRAQ approach, providing a foundation for a better molecular understanding of the pathogenesis of ARTI in children.