Altered biogenesis and microRNA content of hippocampal exosomes following experimental status epilepticus.
journal contributionposted on 19.01.2021, 14:30 by Aasia Batool, Thomas DM Hill, Ngoc Thanh Nguyen, Elena Langa, Mairead Diviney, Catherine Mooney, Gary Brennan, Niamh Connolly, Amaya Sanz Rodriguez, Brenton Cavanagh, David Henshall
Repetitive or prolonged seizures (status epilepticus) can damage neurons within the hippocampus, trigger gliosis, and generate an enduring state of hyperexcitability. Recent studies have suggested that microvesicles including exosomes are released from brain cells following stimulation and tissue injury, conveying contents between cells including microRNAs (miRNAs). Here, we characterized the effects of experimental status epilepticus on the expression of exosome biosynthesis components and analyzed miRNA content in exosome-enriched fractions. Status epilepticus induced by unilateral intra-amygdala kainic acid in mice resulted in acute subfield-specific, bi-directional changes in hippocampal transcripts associated with exosome biosynthesis including up-regulation of endosomal sorting complexes required for transport (ESCRT)-dependent and -independent pathways. Increased expression of exosome components including Alix were detectable in samples obtained 2 weeks after status epilepticus and changes occurred in both the ipsilateral and contralateral hippocampus. RNA sequencing of exosome-enriched fractions prepared using two different techniques detected a rich diversity of conserved miRNAs and showed that status epilepticus selectively alters miRNA contents. We also characterized editing sites of the exosome-enriched miRNAs and found six exosome-enriched miRNAs that were adenosine-to-inosine (ADAR) edited with the majority of the editing events predicted to occur within miRNA seed regions. However, the prevalence of these editing events was not altered by status epilepticus. These studies demonstrate that status epilepticus alters the exosome pathway and its miRNA content, but not editing patterns. Further functional studies will be needed to determine if these changes have pathophysiological significance for epileptogenesis.
Science Foundation Ireland (SFI) grant number 13/IA/1891
European Regional Development Fund
FutureNeuro industry partners.
European Union’s “Seventh Framework” Programme (FP7) under Grant Agreement No. 602130 (EpimiRNA).
Science Foundation Ireland (SFI) grant number 16/RC/3948
Associated research data filesSupplementary material can be found at: https://www.frontiersin.org/articles/10.3389/fnins.2019.01404/full#supplementary-material
CommentsThe original article is available at https://www.frontiersin.org/
Published CitationBatool A, Hill TDM, Nguyen NT, Langa E, Diviney M, Mooney C, Brennan GP, Connolly NMC, Sanz-Rodriguez A, Cavanagh BL, Henshall DC. Altered biogenesis and microRNA content of hippocampal exosomes following experimental status epilepticus. Frontiers in Neuroscience. 2020;13:1404.
Publication Date17 January 2020
- FutureNeuro Centre
- Physiology and Medical Physics
- Neurological and Psychiatric Disorders
PublisherFrontiers Media SA
- Published Version (Version of Record)