Proteomics/phosphoproteomics of left ventricular biopsies from patients with surgical coronary revascularization and pigs with coronary occlusion/reperfusion: remote ischemic preconditioning

Abstract

Remote ischemic preconditioning (RIPC) by repeated brief cycles of limb ischemia/reperfusion reduces myocardial ischemia/reperfusion injury. In left ventricular (LV) biopsies from patients undergoing coronary artery bypass grafting (CABG), only the activation of signal transducer and activator of transcription 5 was associated with RIPC’s cardioprotection. We have now used an unbiased, non-hypothesis-driven proteomics and phosphoproteomics approach to analyze LV biopsies from patients undergoing CABG and from pigs undergoing coronary occlusion/reperfusion without (sham) and with RIPC. False discovery rate-based statistics identified a higher prostaglandin reductase 2 expression at early reperfusion with RIPC than with sham in patients. In pigs, the phosphorylation of 116 proteins was different between baseline and early reperfusion with RIPC and/or with sham. The identified proteins were not identical for patients and pigs, but in-silico pathway analysis of proteins with ≥2-fold higher expression/phosphorylation at early reperfusion with RIPC in comparison to sham revealed a relation to mitochondria and cytoskeleton in both species. Apart from limitations of the proteomics analysis per se, the small cohorts, the sampling/sample processing and the number of uncharacterized/unverifiable porcine proteins may have contributed to this largely unsatisfactory result.

Guidelines for experimental models of myocardial ischemia and infarction

“…Acutely anesthetized animals have provided insight into short-term coronary flow regulation over minutes to hours but cannot evaluate the effects of chronic coronary stenosis on long-term microvascular remodeling and collateral growth over days to weeks ( 285 ). Acute experiments have the advantage that sequential myocardial biopsies can be taken for the analysis of metabolic and molecular analyses ( 101 , 174 , 210 , 283 ). Microdialysis probes can be implanted to evaluate interstitial mediators ( 209 , 270 ), and the activity of the cardiac innervation can be measured ( 132 ).…”

Proteomics Dissection of Cardiac Protein Profiles of Humans and Model Organisms

“…Specifically, we present a quantitative high-resolution map of cardiac protein expression across humans and five common model organisms. Previous studies of model organisms have illuminated portions of their cardiac proteomes 10,19,20 , but often with a particular focus such as cardiac development 21 , disease models 22 , subcellular protein expression 23,24 , phosphorylation [25][26][27] , protein turnover 8,28 or focused on smaller mammals and amphibians 16 or human tissue collected several days post-mortem 29 . No study has been presented that allowed for direct comparison of cardiac protein profiles between model organisms and human.…”

Post-Genomic Methodologies and Preclinical Animal Models: Chances for the Translation of Cardioprotection to the Clinic

“…Gedig et al compared the phosphoproteome of left ventricle biopsies from pigs undergoing coronary occlusion/reperfusion without and with remote ischemic conditioning. They detected that phosphorylation of 116 proteins differed between both groups of animals and those proteins found to have a higher degree of phosphorylation (≥2-fold) in conditioned animals were related with the mitochondria and cytoskeleton [63].…”