Cardiac
Vascular disease particularly
myocardial infarction (MI) is a threat to health worldwide.
microRNAs (
miRNAs) have been shown to regulate myocardial
fibrosis. Therefore, it is potential to investigate the mechanism of
miRNA and
fibrosis following
myocardial infarction.
Hypoxia human cardiac microvascular endothelial cells (HCMECs) were selected for the vitro experimental model. The miR-146a-5p expression was tested via RT-qPCR. The level of endothelial-to-mesenchymal transition (EndMT) and
fibrosis markers were detected by Western blotting and immunofluorescence. Then, the
inflammation, cell viability and apoptosis were investigated. The target was predicted by an online database and verified by a dual-
luciferase activity assay. An MI mouse model was created to validate that miR-146a-5p regulates cardiac
fibrosis in vivo. MI mouse was transfected with miR-146a-5p lentivirus. Subsequently, its effect on cardiac
fibrosis of infarcted hearts was assessed by In situ hybridization (ISH), Immunohistochemistry (IHC), Triphenylterazolium
chloride (TTC) staining and Masson staining. Herein, we confirmed that miR-146a-5p was down-regulated in
hypoxia HCMECs. Overexpression of miR-146a-5p inhibited
hypoxia-induced cardiac
fibrosis following
myocardial infarction by inhibiting EndMT in HCMECs.
Thioredoxin-interacting
protein (TXNIP) was a target that was negatively regulated by miR-146a-5p. Up-regulation of miR-146a-5p inhibited cardiac
fibrosis via regulating EndMT by targeting TXNIP, and it also regulated EndMT to inhibit cardiac
fibrosis in vivo.