Integrative analyses of whole-transcriptome sequencing reveals CeRNA regulatory network in pulmonary hypertension treated with FGF21.

Noncoding RNAs have been shown to play essential roles in hypoxic pulmonary hypertension (HPH). Our preliminary data showed that HPH is attenuated by fibroblast growth factor 21 (FGF21) administration. Therefore, we further investigated the whole transcriptome RNA expression patterns and interactions in a mice HPH model treated with FGF21. By whole-transcriptome sequencing, differentially expressed mRNAs, miRNAs, lncRNAs, and circRNAs were successfully identified in normoxia (Nx) vs. hypoxia (Hx) and Hx vs. hypoxia + FGF21 (Hx + F21). Differentially expressed mRNAs, miRNAs, lncRNAs, and circRNAs regulated by hypoxia and FGF21 were selected through intersection analysis. Based on prediction databases and sequencing data, differentially co-expressed mRNAs, miRNAs, lncRNAs, and circRNAs were further screened, followed by functional enrichment analysis. MAPK signaling pathway and epigenetic modification were enriched and may play fundamental roles in the therapeutic effects of FGF21. The ceRNA regulatory network of lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA was constructed with miR-7a-5p, miR-449c-5p, miR-676-3p and miR-674-3p as the core. In addition, quantitative real-time PCR experiments were employed to verify the whole-transcriptome sequencing data. The results of luciferase reporter assays highlighted the relationship between miR-449c-5p and XR_878320.1, miR-449c-5p and Stab2, miR-449c-5p and circ_mtcp1, which suggesting that miR-449c-5p may be a key regulator of FGF21 in the treatment of PH. Taken together, this study provides potential biomarkers, pathways, and ceRNA regulatory networks in HPH treated with FGF21 and will provide an experimental basis for the clinical application of FGF21 in PH.