AUTHOR=Zhang Juhong , Ma Haizhu , Yang Guijun , Ke Jing , Sun Wenfang , Yang Li , Kuang Shaojing , Li Hai , Yuan Wei 

TITLE=Differentially expressed miRNA profiles of serum-derived exosomes in patients with sudden sensorineural hearing loss

JOURNAL=Frontiers in Neurology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1177988

DOI=10.3389/fneur.2023.1177988

ISSN=1664-2295

ABSTRACT=Objectives: To compare the expressed microRNA (miRNA) profiles of serum-derived exosomes between patients with sudden sensorineural hearing loss (SSNHL) and normal hearing controls to identify exosomal miRNAs that may be associated with SSNHL or serve as biomarkers of SSNHL.
Methods: Peripheral venous blood of patients with SSNHL and healthy controls was collected to isolate exosomes. Nanoparticle tracking analysis, transmission electron microscopy, and western blotting were used to identify the isolated exosomes, after which total RNA was extracted from the exosomes and used for miRNA transcriptome sequencing. Differentially expressed miRNAs (DE-miRNAs) were identified based on the threshold of P<0.05 and subjected to functional analyses. Finally, four exosomal DE-miRNAs, including PC-5p-38556_39, PC-5p-29163_54, PC-5p-31742_49, and hsa-miR-93-3p_R+1, were chosen for validation by quantitative real-time polymerase chain reaction (qRT-PCR).
Results: Exosomes were isolated from serum and confirmed by particle size, morphological examination, and expression of exosome-marker proteins. By differential expression analysis, 18 exosomal DE-miRNAs, including 3 upregulated and 15 downregulated, were found in SSNHL. Gene ontology (GO) functional annotation analysis revealed that the target genes in the top 20 terms were mainly related to “protein binding,” “metal ion binding,” “ATP binding,” and “intracellular signal transduction.” Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that the target genes were functionally enriched in the “Ras,” “Hippo,” “cGMP-PKG,” and “AMPK signaling pathways.” The expression levels of PC-5p-38556_39 and PC-5p-29163_54 were significantly downregulated, and the expression level of miR-93-3p_R+1 was highly upregulated in SSNHL, implying that the consistency rate between sequencing and qRT-PCR was 75% and that the sequencing results were highly reliable.
Conclusions: Our study identified 18 exosomal DE-miRNAs, including eight personally sourced, such as PC-5p-38556_39, PC-5p-29163_54, and miR-93-3p, which may be closely related to SSNHL pathogenesis or serve as biomarkers for SSNHL.