Glycocalyx Preservation and NO Production in Fatty Livers-The Protective Role of High Molecular Polyethylene Glycol in Cold Ischemia Injury.

Alexandre Lopez,Arnau Panisello-Rosello,René Adam,Carlos Castro-Benitez

doi:10.3390/ijms19082375

Alexandre Lopez, Arnau Panisello-Rosello + Show 2 more

Open Access

https://doi.org/10.3390/ijms19082375

Copy DOI

Abstract

Improving the protection of marginal liver grafts during static cold storage is a major hurdle to increase the donor pool of organs. The endothelium glycocalyx quality of preservation influences future inflammatory and oxidative responses. One cellular pathway responsible for the formation of nitric oxide by endothelial cells is dependent on the stimulation of proteoglycans present in the glycocalyx. We investigated the impact of the glycocalyx preservation in static cold storage of fatty liver preserved in different preservation solutions on the endothelium-mediated production of NO. Zucker fatty rat livers were preserved 24 h in static cold storage in either Institut Georges Lopez-1 (IGL-1) (n = 10), IGL-0 (i.e., without PEG35) (n = 5) or Histidine-Tryptophan-Ketoglutarate (HTK) (n = 10) preservation solutions before being processed for analysis. For Sham group (n = 5), the fatty livers were immediately analyzed after procurement. The level of transaminases and nitrites/nitrates were measured in the washing perfusate. Glycocalyx proteins expressions, Syndecan-1, glypican-1 and heparan sulfate (HS), were determined in the tissue (ELISA). Steatotic livers preserved 24 h in IGL-1 preservation solution have a significant lower level of transaminases (aspartate aminotransferase (AST), alanine aminotransferase (ALT)) and less histological damages than steatotic livers preserved 24 h with HTK (p = 0.0152). The syndecan-1 is significantly better preserved in IGL-1 group compared to HTK (p < 0.0001) and we observed the same tendency compared to IGL-0. No significant differences were observed with glypican-1. HS expression in HTK group was significantly higher compared to the three other groups. HS level in IGL-1 was even lower than IGL-0 (p = 0.0005) which was similar to Sham group. The better protection of the glycocalyx proteins in IGL-1 group was correlated with a higher production of NO than HTK (p = 0.0055) or IGL-0 (p = 0.0433). IGL-1 protective mechanisms through the formation of NO could be due to its better protective effects on the glycocalyx during SCS compared to other preservation solutions. This beneficial effect could involve the preservation state of syndecan-1 and the internalization of HS.

Highlights

The shortage of organs and the decrease in the quality of these organs are becoming an increasingly important public health problem in developed countries for the liver transplantation
Level of transaminases (ALT, AST) were measured in the perfusate coming out from the inferior vena cava during the washing of fatty livers directly after procurement (Sham group) or after 24 h of cold storage in Institut Georges Lopez-1 (IGL-1), HTK or IGL-0 preservation solutions (IGL-1, HTK and IGL-0 group respectively) to assess the ischemia–reperfusion injury (IRI) sustained by the fatty livers due to cold ischemia (Figure 1)
Both transaminases levels in Sham groups are significantly lower compared to the transaminases of fatty livers preserved 24 h in HTK (AST: p = 0.007; ALT: p < 0.0001) and IGL-0 (AST: p = 0.0019; ALT: p = 0.0002) preservation solutions (Figure 1a,b)

Summary

Introduction

The shortage of organs and the decrease in the quality of these organs are becoming an increasingly important public health problem in developed countries for the liver transplantation. One solution to increase the donor pool is to use marginal grafts such as steatotic livers. The use of these marginal grafts for liver transplantation could represent a way to increase the donor pool and to reduce the number of patients on the waiting list. Cold ischemia time (CIT) needs to be reduced as much as possible in order to not cause irreversible damages to the liver [1]. This is especially true for fatty livers which are much more sensitive to static cold storage (SCS) compared to non-steatotic livers. The understanding of the underlying mechanisms behind the steatosis is of utmost importance to improve the quality of the preservation and to reduce the postoperative complications for these organs

Methods

Results

Discussion

Conclusion