title: AMP-Activated Protein Kinase α2 in Neutrophils Regulates Vascular Repair via Hypoxia-Inducible Factor-1α and a Network of Proteins Affecting Metabolism and Apoptosis.
abstract: BACKGROUND
  The AMP-activated protein kinase (AMPK) is stimulated by hypoxia, and although the AMPKα1 catalytic subunit has been implicated in angiogenesis, little is known about the role played by the AMPKα2 subunit in vascular repair.
  
  
  OBJECTIVE
  To determine the role of the AMPKα2 subunit in vascular repair.
  
  
  RESULTS
  Recovery of blood flow after femoral artery ligation was impaired (>80%) in AMPKα2-/-versus wild-type mice, a phenotype reproduced in mice lacking AMPKα2 in myeloid cells (AMPKα2ΔMC). Three days after ligation, neutrophil infiltration into ischemic limbs of AMPKα2ΔMCmice was lower than that in wild-type mice despite being higher after 24 hours. Neutrophil survival in ischemic tissue is required to attract monocytes that contribute to the angiogenic response. Indeed, apoptosis was increased in hypoxic neutrophils from AMPKα2ΔMCmice, fewer monocytes were recruited, and gene array analysis revealed attenuated expression of proangiogenic proteins in ischemic AMPKα2ΔMChindlimbs. Many angiogenic growth factors are regulated by hypoxia-inducible factor, and hypoxia-inducible factor-1α induction was attenuated in AMPKα2-deficient cells and accompanied by its enhanced hydroxylation. Also, fewer proteins were regulated by hypoxia in neutrophils from AMPKα2ΔMCmice. Mechanistically, isocitrate dehydrogenase expression and the production of α-ketoglutarate, which negatively regulate hypoxia-inducible factor-1α stability, were attenuated in neutrophils from wild-type mice but remained elevated in cells from AMPKα2ΔMCmice.
  
  
  CONCLUSIONS
  AMPKα2 regulates α-ketoglutarate generation, hypoxia-inducible factor-1α stability, and neutrophil survival, which in turn determine further myeloid cell recruitment and repair potential. The activation of AMPKα2 in neutrophils is a decisive event in the initiation of vascular repair after ischemia.
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Randa
authors: R
authors: Abdel Malik
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Nina
authors: N
authors: Zippel
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Timo
authors: T
authors: Frömel
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Juliana
authors: J
authors: Heidler
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Sven
authors: S
authors: Zukunft
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Barbara
authors: B
authors: Walzog
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Nariman
authors: N
authors: Ansari
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Francesco
authors: F
authors: Pampaloni
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Susanne
authors: S
authors: Wingert
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Michael A
authors: MA
authors: Rieger
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Ilka
authors: I
authors: Wittig
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.).
authors: Beate
authors: B
authors: Fisslthaler
authors: From the Institute for Vascular Signaling, Centre for Molecular Medicine (R.A.M., N.Z., T.F., S.Z., B.F., I.F.), Functional Proteomics, SFB 815 Core Unit, Faculty of Medicine (J.H., I.W.), ECCPS Metabolomics Facility, Institute for Vascular Signaling, Centre for Molecular Medicine (S.Z.), Department of Hematology/Oncology (S.W., M.A.R.), and Buchmann Institute for Molecular Life Sciences (N.A., F.P.), Goethe University, Frankfurt am Main, Germany; German Center of Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (R.A.M., T.F., J.H., S.Z., B.F., I.F.); and Walter-Brendel-Centre of Experimental Medicine, Department of Cardiovascular Physiology and Pathophysiology, Ludwig Maximilians University, Munich, Germany (B.W.). fleming@em.uni-frankfurt.de.
authors: Ingrid
authors: I
authors: Fleming
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000502:physiology*; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001808:Blood Vessels / Q000378:metabolism / Q000473:pathology; D042783:Endothelial Cells / Q000378:metabolism / Q000473:pathology; D006614:Hindlimb / Q000098:blood supply; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D007511:Ischemia / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009504:Neutrophils / Q000378:metabolism*
chemical_list: D051795:Hypoxia-Inducible Factor 1, alpha Subunit; C534978:Prkaa2 protein, mouse; D055372:AMP-Activated Protein Kinases
keywords: diabetes mellitus; ischemia; metabolomics; proteomics; vascular remodeling