Intracerebral hemorrhage alters circular RNA expression profiles in the rat brain

Circular RNAs (circRNAs), formed from pre messenger RNAs by back-splicing, are a novel class of evolutionarily-conserved endogenous non-coding RNAs. While circRNAs are involved in various diseases, the role of circRNAs in intracerebral hemorrhage (ICH) remains unknown. In the present study, we performed high-throughput sequencing to profile the expression of circRNAs in the rat brain at 24 and 48 hours after ICH onset, and utilized bioinformatics methods to make predictions about the function of dysregulated circRNAs. Compared with the sham group, 346 and 389 circRNAs changed significantly (vertical bar log2 (fold change) vertical bar > 1 and P < 0.05) at 24 and 48 hours after ICH, respectively. Bioinformatics analyses indicated that parent genes of dysregulated circRNAs were involved in biological processes, cellular component, and molecular function following ICH, and that they were enriched in the dopaminergic synapses, glutamatergic synapses, endocytosis, regulation of actin cytoskeleton, the mitogen-activated protein kinase signaling pathway, and the retrograde endocannabinoid signaling pathway. Enrichment analyses of target mRNAs showed that these mRNAs were enriched in synaptic plasticity, ion channel activity, and pathways including the phospholipase D signaling and the cGMP-PKG signaling. Our study indicates that the expression profile of circRNAs changes significantly after ICH in rat brains, and suggests that circRNAs may be crucial for the pathophysiological process following ICH.