Angiotensin II induced differentially expressed microRNAs in adult rat cardiac fibroblasts

Angiotensin II (Ang II) plays a pivotal role in cardiac fibrosis, and microRNAs (miRNAs) have been shown to participate in diverse pathological processes. Our aim is to identify the Ang II-induced miRNAs in cardiac fibroblasts (CFs). The miRNA array was used to analyze the miRNA expression profile in CFs treated by Ang II and control cells. Stem-loop real-time PCR was performed to re-measure the levels of the differentially expressed miRNAs. Analysis of miRNA arrays showed that 33 miRNAs were differentially expressed (13 up- and 20 downregulated) in response to Ang II (100 nM) for 24 h as compared to control cells. Quantitative PCR revealed that Ang II upregulated the levels of miR-132, -125b-3p and miR-146b but downregulated the levels of miR-300-5p, -204* and miR-181b in CFs. The trend of miRNA change is consistent with microarray and qRT-PCR. Bioinformatic analysis revealed that MMP9 as the target of miR-132, MMP16 as the target of miR-146b and TIMP3 as the target of miR-181b have been listed in the miR database with experimentally validated targets, indicating the potential role of those miRNAs in cardiac fibrosis. Our results demonstrated that we did identify a subset of miRNAs that was differentially expressed in Ang II-treated CFs, which provide a starting point to explore their potential roles in cardiac fibrosis and hypertension.