title: Mouse hepatocytes and LSEC proteome reveal novel mechanisms of ischemia/reperfusion damage and protection by A2aR stimulation.
abstract: OBJECTIVE
  Ischemia-reperfusion (IR) of liver results in hepatocytes (HP) and sinusoidal endothelial cells (LSEC) irreversible damage. Ischemic preconditioning protects IR damage upon adenosine A2a receptor (A2aR) stimulation. Understanding the phenotypic changes that underlie hepatocellular damage and protection is critical to optimize strategies against IR.
  
  
  METHODS
  The proteome of HP and LSEC, isolated from sham or IR exposed mice, receiving or not the A2aR agonist CGS21680 (0.5mg/kg b.w.), was analyzed by 2-D DIGE/MALDI-TOF.
  
  
  RESULTS
  We identified 64 proteins involved in cytoprotection, regeneration, energy metabolism and response to oxidative stress; among them, 34 were associated with IR injury and A2aR protection. The main pathways, downregulated by IR and upregulated by CGS21680 in HP and LSEC, were related to carbohydrate, protein and lipid supply and metabolism. In LSEC, IR reduced stress response enzymes that were instead upregulated by CGS21680 treatment. Functional validation experiments confirmed the metabolic involvement and showed that inhibition of pyruvate kinase, 3-chetoacylCoA thiolase, and arginase reduced the protection by CGS21680 of in vitro hypoxia-reoxygenation injury, whereas their metabolic products induced liver cell protection. Moreover, LSEC, but not HP, were sensitive to H2O2-induced oxidative damage and CGS21680 protected against this effect.
  
  
  CONCLUSIONS
  IR and A2aR stimulation produces pathological and protected liver cell phenotypes, respectively characterized by down- and upregulation of proteins involved in the response to O2 and nutrients deprivation during ischemia, oxidative stress, and reactivation of aerobic energy synthesis at reperfusion. This provides novel insights into IR hepatocellular damage and protection, and suggests additional therapeutic options.
authors.affiliation: Centre for Experimental and Clinical Studies CERMS, Azienda Universitaria Ospedaliera Città della Salute e della Scienza Città di Torino, Torino, Italy; Department of Molecular Biotechnology and Heath Sciences, University of Torino, Torino, Italy.
authors.forename: Giorgia
authors.initials: G
authors.lastname: Mandili
authors.affiliation: Department of Health Science, University of Piemonte Orientale, Novara, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Alchera
authors.affiliation: Department of Health Science, University of Piemonte Orientale, Novara, Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Merlin
authors.affiliation: Department of Health Science, University of Piemonte Orientale, Novara, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Imarisio
authors.affiliation: Department of Health Science, University of Piemonte Orientale, Novara, Italy.
authors.forename: Bangalore R
authors.initials: BR
authors.lastname: Chandrashekar
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Riganti
authors.affiliation: Department of Health Science, University of Piemonte Orientale, Novara, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Bianchi
authors.affiliation: Centre for Experimental and Clinical Studies CERMS, Azienda Universitaria Ospedaliera Città della Salute e della Scienza Città di Torino, Torino, Italy; Department of Molecular Biotechnology and Heath Sciences, University of Torino, Torino, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Novelli
authors.affiliation: Department of Health Science, University of Piemonte Orientale, Novara, Italy.
authors.forename: Antonia
authors.initials: A
authors.lastname: Follenzi
authors.affiliation: Department of Health Science, University of Piemonte Orientale, Novara, Italy. Electronic address: carini@med.unipmn.it.
authors.forename: Rita
authors.initials: R
authors.lastname: Carini
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives / Q000494:pharmacology; D058908:Adenosine A2 Receptor Agonists / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D019610:Cytoprotection / Q000187:drug effects; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D022781:Hepatocytes / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000293:injuries* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010627:Phenethylamines / Q000494:pharmacology; D020543:Proteome / Q000378:metabolism; D043705:Receptor, Adenosine A2A / Q000378:metabolism*; D015427:Reperfusion Injury / Q000209:etiology* / Q000378:metabolism / Q000517:prevention & control
chemical_list: D058908:Adenosine A2 Receptor Agonists; D000975:Antioxidants; D010627:Phenethylamines; D020543:Proteome; D043705:Receptor, Adenosine A2A; C061282:2-(4-(2-carboxyethyl)phenethylamino)-5'-N-ethylcarboxamidoadenosine; D000241:Adenosine
keywords: Antioxidants; Catabolic pathways; Energetic substrates; Hepatoprotection; Liver damage; Preconditioning