Integrated analyses of lncRNAs microarray profiles and mRNA-lncRNA co-expression in smooth muscle cells under hypoxic and normoxic conditions.

Hypoxia may cause abnormal proliferation and migration of the vascular smooth muscle cells (VSMCs) from the media to the intima. This contributes to vessel narrowing and accelerates the process of atherosclerosis. The association of the aberrant expression of long noncoding RNAs (lncRNAs) with the development and progression of atherosclerosis is well known; however, it is not well investigated in hypoxic VSMCs. Using a microarray approach, we identified 1056 and 2804 differentially expressed lncRNAs and mRNAs, respectively, in hypoxic and normoxic mouse aorta smooth muscle (MOVAS) cells. Of them, we randomly chose several lncRNAs and validated the microarray data using the quantitative PCR (qPCR) assay. Advanced bioinformatics analyses indicated that the up-regulated mRNAs were mainly involved in inflammatory responses, lipid metabolism, clearance of amyloid-beta peptide, citrate cycle (TCA cycle), TGF-beta signaling, and chemokine signaling. The down-regulated mRNAs were mainly involved in the apoptosis pathway, glycerolipid metabolism, Wnt signaling pathway, and MAPK signaling pathway. The constructed co-expression network indicated interactions between 87 lncRNAs and ten mRNAs. In addition, we demonstrated that the silence of lncRNA NONMMUT002434 expression could abrogate the migration and proliferation of smooth muscle cells dramatically. Our data provide comprehensive evidence on the differential expression of lncRNAs and mRNAs in hypoxic MOVAS cells, which may be valuable biomarkers for atherosclerotic diseases, and thereby facilitating diagnosis of atherosclerosis.