Distinct long non-coding RNA and mRNA expression profiles in the hippocampus of an attention deficit hyperactivity disorder model in spontaneously hypertensive rats and control wistar Kyoto rats.

Abstract The incidence of attention deficit hyperactivity disorder (ADHD) in children is increasing. Long non-coding RNAs (lncRNAs) participate in many biological processes involved in the regulation of gene expression. Although numerous lncRNAs have been proven to be crucial in brain development and associated with its degeneration, changes in lncRNA expression profiles during ADHD progression and their possible roles remain unclear. The purpose of this study is to investigate the expression profiles of lncRNAs in hippocampus from an ADHD model in spontaneously hypertensive rats (SHRs) and in normal control Wistar Kyoto (WKY) rats. We determined the expression profiles of lncRNAs and mRNAs in SHRs and WKY rats using microarray analysis technology. Then, differentially expressed lncRNAs were confirmed by real-time polymerase chain reaction (RT-PCR). Gene Ontology (GO) and pathway analysis of differentially expressed mRNAs or nearby genes was used to predict the possible functions of the lncRNAs. A gene co-expression network was established to study the relationship between expression of lncRNAs and related mRNAs. A total of 267 differentially expressed lncRNAs (including 144 upregulated and 123 downregulated) and 311 differentially expressed mRNAs were identified in SHRs, compared to those in WKY rats. Subsequently, 15 lncRNAs were selected and confirmed by RT-PCR analysis. GO and Kyoto Encyclopedia of Genes and Genome (KEGG) pathway analysis showed that the dysregulated lncRNAs are involved in brain developmental processes and neuronal function and maintenance. Co-expression network analysis revealed the close relationship between the differentially expressed lncRNAs and mRNAs. Additionally, co-expression analysis of dysregulated lncRNAs with their downstream genes, which are reported in nervous system and regulation of learning and memory, indicated that lncRNA NONRATT0006598.2 was related to Baiap2 gene, which may participate in ADHD progress. Our findings contribute to understand the importance of lncRNAs and mRNAs in the progression of ADHD, and identify potential therapeutic targets for ADHD treatment.