Abstract
Ischaemia-reperfusion injury (IRI) is closely related to cardiovascular disease (CVD), which is the leading cause of death and disability. Exosomes appear to be involved in several diseases, including CVD. However, the role of mesenchymal stem cell (MSC)-derived exosomes in IRI remains unclear. miRNA expression levels in exosomes from rat normal MSCs or hypoxia-reoxygenation (H/R) MSCs were determined by qPCR and the two significantly upregulated miRNAs were selected for further investigation. Rat cardiomyoblasts (H9c2) were transfected with either miRNA mimics or scramble controls, followed by H/R induction. The effects of miRNA overexpression and exosome administration on H/R damage were then investigated. H/R increased Faslg, suppressed β-catenin, inhibited cell proliferation and migration, and stimulated apoptosis and reactive oxygen species (ROS) production. miR-149 or Let-7c mimics or exosomes reversed H/R-induced damage. The luciferase reporter assay proved the targeted regulation of Faslg by both miR149 and Let-7c. Inhibition of β-catenin suppressed cell migration, proliferation, and ΔΨm but increased apoptosis and ROS. Overall, bone marrow MSC-derived exosomes protected rat cardiomyoblasts from H/R injury via the miR-149/Let-7c/Faslg axis.