title: Cardiac phosphoproteomics during remote ischemic preconditioning: a role for the sarcomeric Z-disk proteins.
abstract: Remote ischemic preconditioning (RIPC) induced by brief ischemia/reperfusion cycles of remote organ (e.g., limb) is cardioprotective. The myocardial cellular changes during RIPC responsible for this phenomenon are not currently known. The aim of this work was to identify the activation by phosphorylation of cardiac proteins following RIPC. To achieve our aim we used isobaric tandem mass tagging (TMT) and reverse phase nanoliquid chromatography tandem spectrometry using a Linear Trap Quadropole (LTQ) Orbitrap Velos mass spectrometer. Male C57/Bl6 mice were anesthetized by an intraperitoneal injection of Tribromoethanol. A cuff was placed around the hind limb and inflated at 200 mmHg to prevent blood flow as confirmed by Laser Doppler Flowmetry. RIPC was induced by 4 cycles of 5 min of limb ischemia followed by 5 min of reperfusion. Hearts were extracted for phosphoproteomics. We identified approximately 30 phosphoproteins that were differentially expressed in response to RIPC protocol. The levels of several phosphoproteins in the Z-disk of the sarcomere including phospho-myozenin-2 were significantly higher than control. This study describes and validates a novel approach to monitor the changes in the cardiac phosphoproteome following the cardioprotective intervention of RIPC and prior to index ischemia. The increased level of phosphorylated sarcomeric proteins suggests they may have a role in cardiac signaling during RIPC.
authors.affiliation: Bristol Heart Institute & School of Clinical Sciences, Faculty of Medicine & Dentistry, University of Bristol, Bristol Royal Infirmary, Level 7, Marlborough Street, Bristol BS2 8HW, UK.
authors.forename: Safa
authors.initials: S
authors.lastname: Abdul-Ghani
authors.affiliation: The Proteomics Facility, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK.
authors.forename: Kate J
authors.initials: KJ
authors.lastname: Heesom
authors.affiliation: Bristol Heart Institute & School of Clinical Sciences, Faculty of Medicine & Dentistry, University of Bristol, Bristol Royal Infirmary, Level 7, Marlborough Street, Bristol BS2 8HW, UK.
authors.forename: Gianni D
authors.initials: GD
authors.lastname: Angelini
authors.affiliation: Bristol Heart Institute & School of Clinical Sciences, Faculty of Medicine & Dentistry, University of Bristol, Bristol Royal Infirmary, Level 7, Marlborough Street, Bristol BS2 8HW, UK.
authors.forename: M-Saadeh
authors.initials: MS
authors.lastname: Suleiman
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D006614:Hindlimb / Q000502:physiology; D019194:Ischemic Preconditioning; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009206:Myocardium / Q000737:chemistry* / Q000378:metabolism; D010750:Phosphoproteins / Q000032:analysis* / Q000378:metabolism; D040901:Proteomics; D015203:Reproducibility of Results; D012518:Sarcomeres / Q000737:chemistry* / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D010750:Phosphoproteins