M2 macrophage-derived exosomes carry microRNA-148a to alleviate myocardial ischemia/reperfusion injury via inhibiting TXNIP and the TLR4/NF-κB/NLRP3 inflammasome signaling pathway

J Mol Cell Cardiol. 2020 May:142:65-79. doi: 10.1016/j.yjmcc.2020.02.007. Epub 2020 Feb 20.

Abstract

Background: Reperfusion may cause injuries to the myocardium in ischemia situation. Emerging studies suggest that exosomes may serve as key mediators in myocardial ischemia/reperfusion (MI/R) injury.

Objective: The study was conducted to figure out the mechanism of M2 macrophage-derived exosomes (M2-exos) in MI/R injury with the involvement of microRNA-148a (miR-148a).

Methods and results: M2 macrophages were prepared and M2-exos were collected and identified. Neonatal rat cardiomyocytes (NCMs) were extracted for in vitro hypoxia/reoxygenation (H/R) model establishment, while rat cardiac tissues were separated for in vivo MI/R model establishment. Differentially expressed miRNAs in NCMs and H/R-treated NCMs after M2-exos treatment were evaluated using microarray analysis. The target relation between miR-148a and thioredoxin-interacting protein (TXNIP) was identified using dual luciferase reporter gene assay. Gain- and loss- of function studies of miR-148a and TXNIP were performed to figure out their roles in MI/R injury. Meanwhile, the activation of the TLR4/NF-κB/NLRP3 inflammasome signaling pathway and pyroptosis of NCMs were evaluated. M2 macrophages carried miR-148a into NCMs. Over-expression of miR-148a enhanced viability of H/R-treated NCMs, reduced infarct size in vivo, and alleviated dysregulation of cardiac enzymes and Ca2+ overload in both models. miR-148a directly bound to the 3'-untranslated region (3'UTR) of TXNIP. Over-expressed TXNIP triggered the TLR4/NF-κB/NLRP3 signaling pathway activation and induced cell pyroptosis of NCMs, and the results were reproduced in in vivo studies.

Conclusion: This study demonstrated that M2-exos could carry miR-148a to mitigate MI/R injury via down-regulating TXNIP and inactivating the TLR4/NF-κB/NLRP3 inflammasome signaling pathway. This study may offer new insights into MI/R injury treatment.

Keywords: Exosomes; M2 macrophages; MicroRNA-148a; Myocardial ischemia/reperfusion injury; TLR4/NF-κB/NLRP3 inflammasome signaling pathway; Thioredoxin-interacting protein.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomarkers
  • Cell Cycle Proteins / metabolism
  • Cell Survival / genetics
  • Disease Models, Animal
  • Disease Susceptibility
  • Exosomes / metabolism*
  • Immunohistochemistry
  • Inflammasomes / metabolism*
  • Macrophages / metabolism*
  • MicroRNAs / genetics*
  • Myocardial Reperfusion Injury / etiology*
  • Myocardial Reperfusion Injury / metabolism*
  • Myocytes, Cardiac / metabolism
  • NF-kappa B / metabolism
  • NLR Family, Pyrin Domain-Containing 3 Protein / genetics
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism
  • Rats
  • Signal Transduction*
  • Toll-Like Receptor 4 / metabolism

Substances

  • Biomarkers
  • Cell Cycle Proteins
  • Inflammasomes
  • MIRN148a microRNA, rat
  • MicroRNAs
  • NF-kappa B
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • TXNIP protein, rat
  • Toll-Like Receptor 4