Ischemic-Preconditioning Induced Serum Exosomal miR-133a-3p Improved Post-Myocardial Infarction Repair via Targeting LTBP1 and PPP2CA

Abstract

Na Yang,1,2,* Yong-Bo Hou,2,3,* Tian-Hao Cui,2 Jun-Ma Yu,2 Shu-Fang He,4,5 Hai-Juan Zhu1 1Department of Anesthesiology, Maternal and Child Medical Center of Anhui Medical University, Hefei, Anhui, People’s Republic of China; 2Department of Anesthesiology, The Third Affiliated Hospital of Anhui Medical University (The First People’s Hospital of Hefei), Hefei, Anhui, People’s Republic of China; 3Department of Anesthesiology, Wannan Medical College, Wuhu, Anhui, People’s Republic of China; 4Department of Anesthesiology and Perioperative Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, People’s Republic of China; 5Key Laboratory of Anesthesiology and Perioperative Medicine of Anhui Higher Education Institutes, Anhui Medical University, Hefei, Anhui, People’s Republic of China*These authors contributed equally to this workCorrespondence: Shu-Fang He; Hai-Juan Zhu, Email [email protected]; [email protected]: Ischemic preconditioning-induced serum exosomes (IPC-exo) protected rat heart against myocardial ischemia/reperfusion injury. However, whether IPC-exo regulate replacement fibrosis after myocardial infarction (MI) and the underlying mechanisms remain unclear. MicroRNAs (miRs) are important cargos of exosomes and play an essential role in cardioprotection. We aim to investigate whether IPC-exo regulate post-MI replacement fibrosis by transferring cardioprotective miRs and its action mechanism.Methods: Exosomes obtained from serum of adult rats in control (Con-exo) and IPC groups were identified and analyzed, subsequently intracardially injected into MI rats following ligation. Their miRs profiles were identified using high-throughput miR sequencing to identify target miRs for bioinformatics analysis. Luciferase reporter assays confirmed target genes of selected miRs. IPC-exo transfected with selected miRs antagomir or NC were intracardially administered to MI rats post-ligation. Cardiac function and degree of replacement fibrosis were detected 4 weeks post-MI.Results: IPC-exo exerted cardioprotective effects against excessive replacement fibrosis. MiR sequencing and RT-qPCR identified miR-133a-3p as most significantly different between IPC-exo and Con-exo. MiR-133a-3p directly targeted latent transforming growth factor beta binding protein 1 (LTBP1) and protein phosphatase 2, catalytic subunit, alpha isozyme (PPP2CA). KEGG analysis showed that transforming growth factor-β (TGF-β) was one of the most enriched signaling pathways with miR-133a-3p. Comparing to injection of IPC-exo transfected with miR-133a-3p antagomir NC, injecting IPC-exo transfected with miR-133a-3p antagomir abolished protective effects of IPC-exo on declining excessive replacement fibrosis and cardiac function enhancement, while increasing the messenger RNA and protein expression of LTBP1, PPP2CA, and TGF-β 1in MI rats.Conclusion: IPC-exo inhibit excessive replacement fibrosis and improve cardiac function post-MI by transferring miR-133a-3p, the mechanism is associated with directly targeting LTBP1 and PPP2CA, and indirectly regulating TGF-β pathway in rats. Our finding provides potential therapeutic effect of IPC-induced exosomal miR-133a-3p for cardiac repair. Keywords: ischemic preconditioning, myocardial infarction, Exosomes, MicroRNAs, cardiac function, myocardial fibrosis

Keywords

• ischemic preconditioning
• myocardial infarction
• exosomes
• micrornas
• cardiac function
• myocardial fibrosis