Abstract: FR-PO1123
Increased Mitochondrial Metabolic Enzymes Are Associated with Superior Kidney Function After Normothermic Ex Vivo Kidney Perfusion: A Proteomics Study
Session Information
- Transplantation: Basic
November 08, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 1901 Transplantation: Basic
Authors
- McEvoy, Caitriona M., University Health Network, Toronto, Ontario, Canada
- Clotet Freixas, Sergi, University Health Network, Toronto, Ontario, Canada
- Tokar, Tomas, Princess Margaret Cancer Centre, Toronto, Ontario, Canada
- Batruch, Ihor, Mount Sinai Hospital, Toronto, Ontario, Canada
- Reid, Shelby, Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Pastrello, Chiara, University Health Network, Toronto, Ontario, Canada
- Urbanellis, Peter, University of Toronto, Toronto, Ontario, Canada
- Robinson, Lisa, The Hospital for Sick Children, Toronto, Ontario, Canada
- Selzner, Markus, Toronto General Hospital, Toronto, Ontario, Canada
- Konvalinka, Ana, University Health Network, Toronto, Ontario, Canada
Background
Normothermic ex-vivo kidney perfusion (NEVKP) is associated with significantly improved graft function following transplantation in comparison to static cold storage (SCS). We hypothesized that NEVKP would induce key alterations in the kidney proteome compared to SCS, and provide insights into the molecular mechanisms central to superior graft function.
Methods
Porcine kidneys were removed following 30 minutes of warm ischemia, and then subjected to either SCS or NEVKP (n=5 each) for 8 hours prior to auto-transplantation. Kidney biopsies were collected at time zero, upon reperfusion, and at POD3. We conducted an unbiased proteomics analysis by LC-MS/MS on Q-Exactive-Plus mass spectrometer. Subsequent analyses were performed using MaxQuant, Perseus, R, pathDIP, mirDIP, and NaVIGATOR.
Results
Kidney function was significantly improved with NEVKP compared to SCS with higher creatinine clearance on POD3 (F-test, p <2.2 x 10-15). We identified 6354 proteins in total (FDR<0.01), with 70 proteins significantly differentially expressed between experimental groups and time points (2-way ANOVA, p<0.05). Gene ontology and pathway enrichment analyses revealed that the proteins increased in NEVKP were significantly associated with the preservation of metabolic processes such as fatty acid ß-oxidation, the TCA cycle and oxidative phosphorylation (e.g. CPT2, MPC2, ETFB, COX4I1). Additionally, proteins associated with the maintenance of adherens junctions and the actin cytoskeleton (e.g. CGNL1, PDLIM4) were enhanced in NEVKP in contrast to SCS. Proteins increased in SCS were associated with RNA binding and protein translation. Comparison with external datasets of ischemia reperfusion injury, and datasets relating to other models of acute and chronic kidney injury confirmed that many of the molecular changes observed in these datasets are expected to be reversed or attenuated by NEVKP.
Conclusion
The proteome-level changes associated with NEVKP demonstrate that the preservation of major metabolic pathways, and of cell polarity and integrity may be pivotal mechanisms by which NEVKP results in improved graft function.