Induction of cardioprotection by small netrin-1-derived peptides.
We have shown that netrin-1 induces potent cardioprotection via extracellular signal-regulated kinases 1 and 2 (ERK1/2)-dependent endothelial nitric oxide synthase (eNOS)/NO activation. The present study investigated cardioprotective effects of small netrin-1-derived peptides. We synthesized three laminin (Lam) V peptides and found those time dependently increased phosphorylation of ERK1/2 and eNOSs1179 in endothelial cells at the same molar concentration used for netrin-1. Preperfusion with Lam V peptides induced a substantial reduction in infarct size (control 39.3 ± 0.2% vs. 14.6 ± 2.3%, 23.0 ± 2.8%, and 18.8 ± 0.8% for V1, V2, and V3, respectively). Furthermore, reperfusion with all three also induced potent cardioprotection (control 37.6 ± 1.3% vs. 17.6 ± 3.2%, 20.6 ± 1.7%, and 15.8 ± 2.0% for V1, V2, and V3, respectively), implicating that these peptides are consistently beneficial whenever they are delivered to the heart. Based on the sequence alignment, we found a region of high sequence homology and synthesized smaller peptides [V1-9 amino acid (aa), V2-10aa, and V3-11aa]. These smaller peptides markedly reduced infarct size during reperfusion (V1-9aa 16.8 ± 2.2%, V2-10aa 18.6 ± 1.7%, and V3-11aa 16.7 ± 3.0% vs. control 37.6 ± 1.3%). A negative control V3-16aa with no sequence homology failed to protect the heart. Of note, the core area has the characteristic sequence of: Cx(1-2)Cx(3-4)Tx(0-1)G. Furthermore, all three smaller peptides induced NO production in endothelial cells that could in turn diffuse to cardiomyocytes to promote survival. Combined applications of V1-9aa and V2-10aa synergistically induced more NO production. Taken together, these data strongly suggest that small netrin-1-derived peptides are highly effective in protecting the heart against myocardial ischemia-reperfusion injury and has the potential to be developed into peptide drugs directly applicable to the treatment of myocardial infarction.
Divisions of Molecular Medicine and Cardiology, Departments of Anesthesiology and Medicine, Cardiovascular Research Laboratories, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California.
Qiang
Q
Li
Divisions of Molecular Medicine and Cardiology, Departments of Anesthesiology and Medicine, Cardiovascular Research Laboratories, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California hcai@mednet.ucla.edu.
Hua
H
Cai
D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D019610:Cytoprotection; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008810:Mice, Inbred C57BL; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D009414:Nerve Growth Factors / Q000494:pharmacology*; D000075388:Netrin-1; D009569:Nitric Oxide / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D019899:Paracrine Communication / Q000187:drug effects; D010446:Peptide Fragments / Q000494:pharmacology*; D010766:Phosphorylation; D020011:Protective Agents / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D025521:Tumor Suppressor Proteins / Q000494:pharmacology*
D009414:Nerve Growth Factors; C000617353:Ntn1 protein, mouse; D010446:Peptide Fragments; D020011:Protective Agents; D025521:Tumor Suppressor Proteins; D000075388:Netrin-1; D009569:Nitric Oxide; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse; C535148:Mapk1 protein, mouse; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3
ERK1/2; I/R; cardioprotection; eNOS; endothelial nitric oxide synthase; ischemia-reperfusion injury; netrin-1-derived small peptides