title: Bioactive lipids and cationic antimicrobial peptides as new potential regulators for trafficking of bone marrow-derived stem cells in patients with acute myocardial infarction.
abstract: Acute myocardial infarction (AMI) triggers mobilization of stem cells from bone marrow (BM) into peripheral blood (PB). Based on our observation that the bioactive sphingophospholipids, sphingosine-1 phosphate (S1P), and ceramide-1 phosphate (C1P) regulate trafficking of hematopoietic stem cells (HSCs), we explored whether they also direct trafficking of non-hematopoietic stem cells (non-HSCs). We detected a 3-6-fold increase in circulating CD34+, CD133+, and CXCR4+ lineage-negative (Lin-)/CD45- cells that are enriched in non-HSCs [including endothelial progenitors (EPCs) and very small embryonic-like stem cells (VSELs)] in PB from AMI patients (P<0.05 vs. controls). Concurrently, we measured a ∼3-fold increase in S1P and C1P levels in plasma from AMI patients. At the same time, plasma obtained at hospital admission and 6 h after AMI strongly chemoattracted human BM-derived CD34+/Lin- and CXCR4+/Lin- cells in Transwell chemotaxis assays. This effect of plasma was blunted after depletion of S1P level by charcoal stripping and was further inhibited by the specific S1P1 receptor antagonist such as W146 and VPC23019. We also noted that the expression of S1P receptor 1 (S1P1), which is dominant in naïve BM, is reduced after the exposure to S1P at concentrations similar to the plasma S1P levels in patients with AMI, thus influencing the role of S1P in homing to the injured myocardium. Therefore, we examined mechanisms, other than bioactive lipids, that may contribute to the homing of BM non-HSCs to the infarcted myocardium. Hypoxic cardiac tissue increases the expression of cathelicidin and β-2 defensin, which could explain why PB cells isolated from patients with AMI migrated more efficiently to a low, yet physiological, gradient of stromal-derived factor-1 in Transwell migration assays. Together, these observations suggest that while elevated S1P and C1P levels early in the course of AMI may trigger mobilization of non-HSCs into PB, cathelicidin and β-2 defensin could play an important role in their homing to damaged myocardium.
authors.affiliation: Gill Heart Institute and Division of Cardiovascular Medicine, University of Kentucky, Lexington, Kentucky 40536-0200, USA.
authors.forename: Anush V
authors.initials: AV
authors.lastname: Karapetyan
authors.forename: Yuri M
authors.initials: YM
authors.lastname: Klyachkin
authors.forename: Samy
authors.initials: S
authors.lastname: Selim
authors.forename: Manjula
authors.initials: M
authors.lastname: Sunkara
authors.forename: Khaled M
authors.initials: KM
authors.lastname: Ziada
authors.forename: Donald A
authors.initials: DA
authors.lastname: Cohen
authors.forename: Ewa K
authors.initials: EK
authors.lastname: Zuba-Surma
authors.forename: Janina
authors.initials: J
authors.lastname: Ratajczak
authors.forename: Susan S
authors.initials: SS
authors.lastname: Smyth
authors.forename: Mariusz Z
authors.initials: MZ
authors.lastname: Ratajczak
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Morris
authors.forename: Ahmed
authors.initials: A
authors.lastname: Abdel-Latif
mesh_terms: D000071916:AC133 Antigen; D000818:Animals; D015703:Antigens, CD / Q000097:blood; D018952:Antigens, CD34 / Q000097:blood; D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000378:metabolism; D015687:Cell Hypoxia; D002465:Cell Movement; D002518:Ceramides / Q000378:metabolism*; D054377:Chemokine CXCL12 / Q000378:metabolism; D006023:Glycoproteins / Q000097:blood; D019650:Hematopoietic Stem Cell Mobilization; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D008246:Lysophospholipids / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D009203:Myocardial Infarction / Q000628:therapy*; D009206:Myocardium / Q000166:cytology / Q000378:metabolism; D010455:Peptides / Q000097:blood; D019718:Receptors, CXCR4 / Q000097:blood; D049349:Receptors, Lysosphingolipid / Q000097:blood; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000378:metabolism; D023083:beta-Defensins / Q000096:biosynthesis; D054804:Cathelicidins
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D018952:Antigens, CD34; D023181:Antimicrobial Cationic Peptides; C515255:CXCL12 protein, human; C527276:CXCR4 protein, human; D002518:Ceramides; D054377:Chemokine CXCL12; D006023:Glycoproteins; D008246:Lysophospholipids; C000606023:PROM1 protein, human; D010455:Peptides; C000606024:Prom1 protein, mouse; D019718:Receptors, CXCR4; D049349:Receptors, Lysosphingolipid; D023083:beta-Defensins; C065576:ceramide 1-phosphate; C060506:sphingosine 1-phosphate; D013110:Sphingosine; D054804:Cathelicidins