title: Comparative proteomic analysis of rat left ventricle in a subtotal nephrectomy model.
abstract: BACKGROUND
  Chronic kidney disease (CKD) is associated with cardiac hypertrophy that leads to increased cardiovascular morbidity and mortality. To date, use of the renin-angiotensin-aldosterone system blockade has been the main treatment modality. However, renin-angiotensin-aldosterone system blockade by the angiotensin converting enzyme inhibitors (ACEi) can only partially reverse the cardiac hypertrophy without having a significant impact on all-cause mortality as evidenced by meta-analyses from clinical trials. It is imperative to elucidate the molecular pathogenesis of CKD-related cardiomyopathy for potential targets in further treatment.
  
  
  METHODS
  Male Sprague-Dawley rats that underwent subtotal nephrectomy (SNX) rats were established as the CKD model. A hemodynamic study was used to evaluate the left ventricle (LV) structural and functional alterations. We used proteomic techniques to profile the LV protein changes among sham-operated rats, SNX rats, and SNX rats with 6 months of ACEi enalapril interventions. The differentially expressed proteins were further annotated by functional and network analyses.
  
  
  RESULTS
  As compared to the sham-operated rats, the SNX rats had 25 upregulated and 46 decreased protein expression. The top canonical pathways identified by ingenuity pathway analysis for the CKD cardiomyopathy were mitochondrial dysfunction, oxidative phosphorylation, fatty acid β oxidation, protein ubiquitination, and ketolysis. The most relevant functions extracted from these networks contained 27 and 23 focused proteins, respectively. They were related to cellular assembly and organization, RNA posttranscriptional modification, and protein synthesis. After ACEi intervention for 6 weeks, the residual canonical pathways identified by ingenuity pathway analysis that mediated the CKD-related cardiomyopathy were mitochondrial dysfunction, ketolysis, phenylalanine degradation IV, and putrescine degradation III. There were decreased Sirt3 and SNRNP, and increased monoamine oxidase and SAHH expression in the LV of SNX rats that could not be reversed by the ACEi.
  
  
  CONCLUSIONS
  Our studies provide a repertoire of potential biomarkers related to cardiac hypertrophy in CKD. There are still residual disturbed molecules/pathways despite ACEi intervention. Further studies are warranted to investigate these potential novel targets to alleviate CKD-related cardiomyopathy.
authors.affiliation: National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC; Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Yao-Ping
authors.initials: YP
authors.lastname: Lin
authors.affiliation: National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC; Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Yu
authors.affiliation: Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Meng-Erh
authors.initials: ME
authors.lastname: Hsu
authors.affiliation: Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Hsiao-Chien
authors.initials: HC
authors.lastname: Tsai
authors.affiliation: Proteomics Research Center, National Yang-Ming University, Taipei, Taiwan, ROC. Electronic address: ccliao@ym.edu.tw.
authors.forename: Chen-Chung
authors.initials: CC
authors.lastname: Liao
authors.affiliation: Proteomics Research Center, National Yang-Ming University, Taipei, Taiwan, ROC; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Education and Research, Taipei City Hospital, Taipei, Taiwan, ROC; Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan, ROC.
authors.forename: Chao-Hsiung
authors.initials: CH
authors.lastname: Lin
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D000818:Animals; D015153:Blotting, Western; D009202:Cardiomyopathies / Q000188:drug therapy* / Q000209:etiology; D004195:Disease Models, Animal; D004656:Enalapril / Q000627:therapeutic use; D006352:Heart Ventricles / Q000737:chemistry*; D006439:Hemodynamics; D008297:Male; D009392:Nephrectomy; D040901:Proteomics / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D051436:Renal Insufficiency, Chronic / Q000150:complications* / Q000503:physiopathology
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D004656:Enalapril
keywords: angiotensin converting enzyme inhibitor; chronic kidney disease; hemodynamics; left ventricular hypertrophy; proteomics