Diannexin Protects against Renal Ischemia Reperfusion Injury and Targets Phosphatidylserines in Ischemic Tissue

Leon J De Windt,Kimberley E Wever,Rosalinde Masereeuw,Cathelijne Frielink,Anthony Allison,Gerard A Rongen,Frank A D T G Wagener,Otto C Boerman,Gert J Scheffer

doi:10.1371/journal.pone.0024276

Leon J De Windt, Kimberley E Wever + Show 7 more

Open Access

https://doi.org/10.1371/journal.pone.0024276

Copy DOI

Abstract

Renal ischemia/reperfusion injury (IRI) frequently complicates shock, renal transplantation and cardiac and aortic surgery, and has prognostic significance. The translocation of phosphatidylserines to cell surfaces is an important pro-inflammatory signal for cell-stress after IRI. We hypothesized that shielding of exposed phosphatidylserines by the annexin A5 (ANXA5) homodimer Diannexin protects against renal IRI. Protective effects of Diannexin on the kidney were studied in a mouse model of mild renal IRI. Diannexin treatment before renal IRI decreased proximal tubule damage and leukocyte influx, decreased transcription and expression of renal injury markers Neutrophil Gelatinase Associated Lipocalin and Kidney Injury Molecule-1 and improved renal function. A mouse model of ischemic hind limb exercise was used to assess Diannexin biodistribution and targeting. When comparing its biodistribution and elimination to ANXA5, Diannexin was found to have a distinct distribution pattern and longer blood half-life. Diannexin targeted specifically to the ischemic muscle and its affinity exceeded that of ANXA5. Targeting of both proteins was inhibited by pre-treatment with unlabeled ANXA5, suggesting that Diannexin targets specifically to ischemic tissues via phosphatidylserine-binding. This study emphasizes the importance of phosphatidylserine translocation in the pathophysiology of IRI. We show for the first time that Diannexin protects against renal IRI, making it a promising therapeutic tool to prevent IRI in a clinical setting. Our results indicate that Diannexin is a potential new imaging agent for the study of phosphatidylserine-exposing organs in vivo.

Highlights

Ischemia/reperfusion injury (IRI) is a major cause of cardiovascular morbidity and mortality [1]
We demonstrate for the first time that DA5 ameliorates renal function after IRI, reduces leukocyte influx and tubular damage and reduces renal injury marker expression
We investigated the effects of DA5 pretreatment on ischemic kidney damage in a mouse model of bilateral renal IRI

Summary

Introduction

Ischemia/reperfusion injury (IRI) is a major cause of cardiovascular morbidity and mortality [1]. Renal IRI is a major cause of acute kidney injury (AKI), and is commonly observed in e.g. renal artery stenosis, sepsis, and various types of renal surgery [4,5]. The characteristic pathologic changes associated with IRI induced AKI are classically believed to be acute tubular necrosis and interstitial inflammatory cell infiltration [6,7]. The activation of endothelial cells in microcirculatory vessels is an important event in the inflammatory response upon IRI. The translocation of phosphatidylserines (PS) to the outer leaflet of the endothelial cell plasma membrane appears to play a central role in the cascades leading to end-organ damage [9,10]

Objectives

Methods

Results

Conclusion