DioxolaneA3-phosphatidylethanolamines are generated by human platelets and stimulate neutrophil integrin expression.
Activated platelets generate an eicosanoid proposed to be 8-hydroxy-9,10-dioxolane A3 (DXA3). Herein, we demonstrate that significant amounts of DXA3are rapidly attached to phosphatidylethanolamine (PE) forming four esterified eicosanoids, 16:0p, 18:0p, 18:1p and 18:0a/DXA3-PEs that can activate neutrophil integrin expression. These lipids comprise the majority of DXA3generated by platelets, are formed in ng amounts (24.3±6.1ng/2×108) and remain membrane bound. Pharmacological studies revealed DXA3-PE formation involves cyclooxygenase-1 (COX), protease-activated receptors (PAR) 1 and 4, cytosolic phospholipase A2(cPLA2), phospholipase C and intracellular calcium. They are generated primarily via esterification of newly formed DXA3,but can also be formed in vitro via co-oxidation of PE during COX-1 co-oxidation of arachidonate. All four DXA3-PEs were detected in human clots. Purified platelet DXA3-PE activated neutrophil Mac-1 expression, independently of its hydrolysis to the free eicosanoid. This study demonstrates the structures and cellular synthetic pathway for a family of leukocyte-activating platelet phospholipids generated on acute activation, adding to the growing evidence that enzymatic PE oxidation is a physiological event in innate immune cells.
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK.
Maceler
M
Aldrovandi
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK.
Christine
C
Hinz
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK.
Sarah N
SN
Lauder
ThermoFisher Scientific, Stafford House, Boundary Way, Hemel Hempstead HP2 7GE, United Kingdom.
Helen
H
Podmore
ThermoFisher Scientific, Stafford House, Boundary Way, Hemel Hempstead HP2 7GE, United Kingdom.
Martin
M
Hornshaw
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK.
David A
DA
Slatter
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK.
Victoria J
VJ
Tyrrell
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK.
Stephen R
SR
Clark
Vanderbilt Institute of Chemical Biology, Centre in Molecular Toxicology, Vanderbilt-Ingram Cancer Centre, Nashville, TN, USA.
Lawrence J
LJ
Marnett
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK.
Peter W
PW
Collins
Department of Pharmacology, University of Colorado Denver, Aurora, CO 80045, USA.
Robert C
RC
Murphy
Systems Immunity Research Institute, and Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, UK. Electronic address: o-donnellvb@cardifff.ac.uk.
Valerie B
VB
O'Donnell
D001792:Blood Platelets / Q000378:metabolism*; D002118:Calcium / Q000097:blood; D051545:Cyclooxygenase 1 / Q000097:blood; D004148:Dioxolanes / Q000097:blood*; D015777:Eicosanoids / Q000097:blood; D005786:Gene Expression Regulation; D006801:Humans; D016023:Integrins / Q000096:biosynthesis / Q000097:blood*; D008055:Lipids / Q000097:blood*; D016177:Macrophage-1 Antigen / Q000235:genetics; D009504:Neutrophils / Q000378:metabolism; D010084:Oxidation-Reduction; D010714:Phosphatidylethanolamines / Q000097:blood*; D054510:Phospholipases A2, Cytosolic / Q000097:blood; D015539:Platelet Activation / Q000235:genetics; D044463:Receptor, PAR-1 / Q000097:blood; D018179:Receptors, Thrombin / Q000097:blood; D013917:Thrombin / Q000378:metabolism; D010738:Type C Phospholipases / Q000097:blood
D004148:Dioxolanes; D015777:Eicosanoids; D016023:Integrins; D008055:Lipids; D016177:Macrophage-1 Antigen; D010714:Phosphatidylethanolamines; D044463:Receptor, PAR-1; D018179:Receptors, Thrombin; C483858:phosphatidylethanolamine; D051545:Cyclooxygenase 1; D054510:Phospholipases A2, Cytosolic; D010738:Type C Phospholipases; D013917:Thrombin; C112908:protease-activated receptor 4; D002118:Calcium; C010962:formal glycol
Cyclooxygenase; Eicosanoids; Mass spectrometry; Phospholipids; Platelets