title: 12(S)-HETrE, a 12-Lipoxygenase Oxylipin of Dihomo-γ-Linolenic Acid, Inhibits Thrombosis via Gαs Signaling in Platelets.
abstract: Dietary supplementation with polyunsaturated fatty acids has been widely used for primary and secondary prevention of cardiovascular disease in individuals at risk; however, the cardioprotective benefits of polyunsaturated fatty acids remain controversial because of lack of mechanistic and in vivo evidence. We present direct evidence that an omega-6 polyunsaturated fatty acid, dihomo-γ-linolenic acid (DGLA), exhibits in vivo cardioprotection through 12-lipoxygenase (12-LOX) oxidation of DGLA to its reduced oxidized lipid form, 12(S)-hydroxy-8Z,10E,14Z-eicosatrienoic acid (12(S)-HETrE), inhibiting platelet activation and thrombosis.
  
  
  
  DGLA inhibited ex vivo platelet aggregation and Rap1 activation in wild-type mice, but not in mice lacking 12-LOX expression (12-LOX(-/-)). Similarly, wild-type mice treated with DGLA were able to reduce thrombus growth (platelet and fibrin accumulation) after laser-induced injury of the arteriole of the cremaster muscle, but not 12-LOX(-/-) mice, supporting a 12-LOX requirement for mediating the inhibitory effects of DGLA on platelet-mediated thrombus formation. Platelet activation and thrombus formation were also suppressed when directly treated with 12(S)-HETrE. Importantly, 2 hemostatic models, tail bleeding and arteriole rupture of the cremaster muscle, showed no alteration in hemostasis after 12(S)-HETrE treatment. Finally, the mechanism for 12(S)-HETrE protection was shown to be mediated via a Gαs-linked G-protein-coupled receptor pathway in human platelets.
  
  
  
  This study provides the direct evidence that an omega-6 polyunsaturated fatty acid, DGLA, inhibits injury-induced thrombosis through its 12-LOX oxylipin, 12(S)-HETrE, which strongly supports the potential cardioprotective benefits of DGLA supplementation through its regulation of platelet function. Furthermore, this is the first evidence of a 12-LOX oxylipin regulating platelet function in a Gs α subunit-linked G-protein-coupled receptor-dependent manner.
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Jennifer
authors.initials: J
authors.lastname: Yeung
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Tourdot
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Reheman
authors.initials: R
authors.lastname: Adili
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Abigail R
authors.initials: AR
authors.lastname: Green
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Cody J
authors.initials: CJ
authors.lastname: Freedman
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Pilar
authors.initials: P
authors.lastname: Fernandez-Perez
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Johnny
authors.initials: J
authors.lastname: Yu
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.).
authors.forename: Theodore R
authors.initials: TR
authors.lastname: Holman
authors.affiliation: From the Department of Pharmacology (J.Y., B.E.T., R.A., M.H.) and Department of Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor; Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA (J.Y., B.E.T., R.A., P.F.-P., J.Y., M.H.); and Department of Chemistry and Biochemistry, University of California Santa Cruz (A.R.G., C.J.F., T.R.H.). mholinst@umich.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Holinstat
mesh_terms: D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000097:blood* / Q000172:deficiency / Q000235:genetics; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000097:blood; D002864:Chromogranins / Q000097:blood*; D000242:Cyclic AMP / Q000097:blood; D017868:Cyclic AMP-Dependent Protein Kinases / Q000097:blood; D004195:Disease Models, Animal; D005343:Fibrinolytic Agents / Q000378:metabolism / Q000494:pharmacology*; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000097:blood*; D006801:Humans; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008840:Microfilament Proteins / Q000097:blood; D010084:Oxidation-Reduction; D010750:Phosphoproteins / Q000097:blood; D010766:Phosphorylation; D015539:Platelet Activation / Q000187:drug effects*; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D000089804:Shelterin Complex; D015398:Signal Transduction / Q000187:drug effects; D034501:Telomere-Binding Proteins / Q000097:blood; D013927:Thrombosis / Q000097:blood / Q000201:enzymology / Q000235:genetics / Q000517:prevention & control*; D013997:Time Factors; D000098662:Vasodilator-Stimulated Phosphoprotein
chemical_list: C000620299:12-hydroxy-8,10,14-eicosatrienoic acid; D015815:Cell Adhesion Molecules; D002864:Chromogranins; D005343:Fibrinolytic Agents; D008840:Microfilament Proteins; D010750:Phosphoproteins; D010975:Platelet Aggregation Inhibitors; D000089804:Shelterin Complex; C548558:TERF2IP protein, mouse; D034501:Telomere-Binding Proteins; D000098662:Vasodilator-Stimulated Phosphoprotein; D000242:Cyclic AMP; D001092:Arachidonate 12-Lipoxygenase; C476558:ALOX12 protein, human; D017868:Cyclic AMP-Dependent Protein Kinases; C406732:GNAS protein, human; D019205:GTP-Binding Protein alpha Subunits, Gs; D015126:8,11,14-Eicosatrienoic Acid
keywords: blood platelets; eicosanoids; fibrin; lipoxygenase; platelet activation; thrombosis