Resolution Agonist 15-epi-Lipoxin A4 Programs Early Activation of Resolving Phase in Post-Myocardial Infarction Healing

Sci Rep. 2017 Aug 30;7(1):9999. doi: 10.1038/s41598-017-10441-8.

Abstract

Following myocardial infarction (MI), overactive inflammation remodels the left ventricle (LV) leading to heart failure coinciding with reduced levels of 15-epi-Lipoxin A4 (15-epi LXA4). However, the role of 15-epi LXA4 in post-MI acute inflammatory response and resolving phase is unclear. We hypothesize that liposomal fusion of 15-epi-LXA4 (Lipo-15-epi-LXA4) or free 15-epi-LXA4 will expedite the resolving phase in post-MI inflammation. 8 to 12-week-old male C57BL/6 mice were subjected to permanent coronary artery ligation. Lipo-15-epi-LXA4 or 15-epi-LXA4 (1 µg/kg/day) was injected 3 hours post-MI for (d)1 or continued daily till d5. 15-epi-LXA4 activated formyl peptide receptor (FPR2) and GPR120 on alternative macrophages but inhibited GPR40 on classical macrophages in-vitro. The 15-epi-LXA4 injected mice displayed reduced LV and lung mass to body weight ratios and improved ejection fraction at d5 post-MI. In the acute phase of inflammation-(d1), 15-epi-LXA4 primes neutrophil infiltration with a robust increase of Ccl2 and FPR2 expression. During the resolving phase-(d5), 15-epi-LXA4 initiated rapid neutrophils clearance with persistent activation of FPR2 in LV. Compared to MI-control, 15-epi-LXA4 injected mice showed reduced renal inflammation along with decreased levels of ngal and plasma creatinine. In summary, 15-epi-LXA4 initiates the resolving phase early to discontinue inflammation post-MI, thereby reducing LV dysfunction.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents, Non-Steroidal / administration & dosage*
  • Disease Models, Animal
  • Heart Ventricles / pathology
  • Lipoxins / administration & dosage*
  • Lung / pathology
  • Macrophages / immunology
  • Male
  • Mice, Inbred C57BL
  • Myocardial Infarction / drug therapy*
  • Myocardial Infarction / pathology*
  • Treatment Outcome
  • Ventricular Remodeling / drug effects

Substances

  • Anti-Inflammatory Agents, Non-Steroidal
  • Lipoxins
  • lipoxin A4