Intestinal preservation using a tailored luminal solution and aeration: A small animal study

Background: Oxygenation during organ preservation has been suggested to enhance outcomes after transplantation, however, data is scarce regarding the intestine. We compared static cold storage (SCS) with two alternative approaches: a luminal polyethylene glycol solution enriched with glutamine and arginine (PEG-GAs), and the same luminal PEG solution combined with air insufflation. Methods: Small intestines of Sprague-Dawley rats were perfused in-situ with cold IGL-1, then divided into 3 segments: group 1 maintained in SCS, group 2 receiving additional luminal PEG-GAs and group 3 receiving luminal PEG-GAs and additional air insufflation. Samples were taken after eight, fourteen and 24 h of cold storage and analysed with western blot and histological assessment using light microscopy, immunofluorescence. Results: Intestinal grafts in groups 2 and 3 exhibited a consistent trend towards lower histological injury scores at all time points compared to group 1. Goblet cell depletion occurred more rapidly in group 1; zonula occludens-1 decreased rapidly in group 1 but was maintained for at least 14 h in groups 2 and 3. Tissue expression of several other tight junction (claudin 3 och 4, occludin, tricellulin) proteins also varied, suggesting a gradually compromised epithelial integrity in group 1 relative to the other two groups. Higher levels of caspase 3 expression were noted in group 1 at all time-points. Conclusion: The current results confirm that extensive tissue and molecular alterations ensue within eight hours of intestinal SCS. This study did not demonstrate significant advantages of additional air insufflation in the preservation solution over luminal preservation alone.