CHBP in Preservation Solution and Autologous Blood Perfusate Protects Isolated Ischemic Porcine Kidneys.

Abstract

Introduction. There is an imperative need to develop new approaches to prevent ischemia reperfusion injury (IRI) during organ cold storage (CS) and reperfusion. A novel cyclic helix B peptide (CHBP) derived from erythropoietin was newly synthesized and its renoprotective roles were evaluated in an ex vivo renal model. Methods. Porcine kidneys subjected to 20 min warm ischemia were retrieved and flushed with 500 ml hyperosmolar citrate. The kidneys, as well as autologous blood, were cold preserved with or without 10.56 nmol/L CHBP for 18 hr. The kidneys were then reperfused with oxygenated autologous blood for 3 hr on an isolated organ perfusion system to assess renal function and structure, caspase-3 expression, apoptosis and inflammation. Results. CHBP significantly increased renal blood flow during 2 to 3 h reperfusion, with increased oxygen consumption and urine output, but decreased serum potassium. 32 kD precursor, as well as 12 and 17 kD active subunits of caspase-3 were all down-regulated by CHBP in after 3 h reperfusion, while only the 12 kD subunit was decreased post CS. In addition, apoptotic cells were significantly decreased in tubular areas, but increased in lumens and interstitial areas in post CS and reperfusion kidneys. Heat shock protein 70 was up-regulated; myeloperoxidase+ cells was reduced and renal tissue damage was also ameliorated by CHBP. Conclusions. The administration of CHBP during cold preservation of kidneys as well as autologous blood ameliorated IRI after hemoreperfusion with better renal blood flow, oxygenation, tubular function and tissue structure, which might be due to decreased caspase-3 protein, apoptosis and inflammation.Figure: No Caption available.