Effect of PERLA®, a new cold-storage solution, on oxidative stress injury and early graft function in rat kidney transplantation model

BACKGROUND

The composition of organ preservation solutions is crucial for maintaining graft integrity and early graft function after transplantation. The aim of this study is to compare new organ preservation solution PERLA® with the gold standard preservation solution University of Wisconsin (UW) regarding oxidative stress and early graft injury.

METHODS

In order to assess oxidative stress after cold storage, kidney grafts have been preserved for 18 h at 4° C in either UW solution or PERLA® solution and then assessed for oxidative stress injury (protocol 1). To assess kidney injuries and oxidative stress after reperfusion, rat kidneys were harvested, stored in cold UW or in PERLA® solutions for 18 h at 4 °C and then transplanted heterotopically for 6 h (protocol 2). PERLA® is a high Na+/low K+ solution including PEG-35 (1 g/L), trimetazidine (1 µM), carvedilol (10 µM) and tacrolimus (5 µM).

RESULTS

Our results showed that preservation of kidneys in PERLA® solution significantly attenuates oxidative stress parameters after cold storage and reperfusion. We found a significant decrease in oxidative damage indicators (MDA, CD and CP) and a significant increase in antioxidant indicators (GPx, GSH, CAT, SOD and PSH). Moreover, PERLA® solution decreased kidney injury after reperfusion (creatinine, LDH and uric acid).

CONCLUSION

PERLA® solution was more effective than UW storage solution in preserving rat's kidney grafts.

Perrault, Maximilian Y Emmert and entitled: preservation solutions to improve graft patency: The devil is in the detail)

Not applicable.

Systematic review of preservation solutions for allografts for liver transplantation based on a network meta-analysis

AIMS

The aim of this work was to determine the best preservation solutions for allografts for liver transplantation by quantitative network meta-analysis.

METHODS

Global electronic databases including PubMed, EMBASE, and Cochrane Library were searched for relevant randomized controlled trials. Seven pieces of parametric data were extracted from included studies for pooled estimation. A consistency model was used for direct and indirect comparisons. The cumulative probability P value was utilized to rank the solutions. A node-splitting model was utilized for testing the consistency of final data. Quality of evidence was assessed using the GRADE (Grades of Recommendations Assessment, Development and Evaluation) system.

RESULTS

Eleven 2-arm trials including 1319 patients and 5 different solutions were finally included. HTK (Histidine-tryptophan-ketoglutarate) solution exhibited the best efficacy for decreasing the primary dysfunction rate, biliary complications and ICU-stay time (probability P = 0.43, 0.45 and 0.58, respectively). Celsior solution significantly decreased the rate of rejection and early retransplantation (probability P = 0.73 and 0.38, respectively), and enhanced patient and graft survival (probability P = 0.90 and 0.98, respectively) more than did other solutions. Overall, the quality of evidence was rated high or moderate.

CONCLUSIONS

We suggested that HTK solution may offer the best safety during the perioperative period. However, Celsior solution led to better graft tolerance and exhibited greater benefit for long-term outcomes. And our conclusions still need to be further validated.

Emerging concepts in liver graft preservation

The urgent need to expand the donor pool in order to attend to the growing demand for liver transplantation has obliged physicians to consider the use of suboptimal liver grafts and also to redefine the preservation strategies. This review examines the different methods of liver graft preservation, focusing on the latest advances in both static cold storage and machine perfusion (MP). The new strategies for static cold storage are mainly designed to increase the fatty liver graft preservation via the supplementation of commercial organ preservation solutions with additives. In this paper we stress the importance of carrying out effective graft washout after static cold preservation, and present a detailed discussion of the future perspectives for dynamic graft preservation using MP at different temperatures (hypothermia at 4 °C, normothermia at 37 °C and subnormothermia at 20 °C-25 °C). Finally, we highlight some emerging applications of regenerative medicine in liver graft preservation. In conclusion, this review discusses the "state of the art" and future perspectives in static and dynamic liver graft preservation in order to improve graft viability.

Preservation of the donor heart: from basic science to clinical studies

The methods of donor heart preservation are aimed at minimizing graft dysfunction caused by ischaemia-reperfusion injury (IRI) which inevitably occurs during the ex vivo transport interval. At present, the standard technique of heart preservation is cardiac arrest followed by static cold storage in a crystalloid heart preservation solution (HPS). This technique ensures an acceptable level of heart protection against IRI for <6 h. In clinical trials, comparable levels of myocardial protection against IRI were provided by various HPSs. The growing shortage of donor hearts is one of the major factors stimulating the development of new techniques of heart preservation. Here, we summarize new HPS formulations and provide a focus for optimization of the composition of existing HPSs. Such methods of donor heart preservation as machine perfusion, preservation at sub-zero temperature and oxygen persufflation are also discussed. Furthermore, we review experimental data showing that pre- and post-conditioning of the cardiac graft can improve its function when used in combination with cold storage. The evidence on the feasibility of cardiac donation after circulatory death, as well as the techniques of heart reconditioning after a period of warm ischaemia, is presented. The implementation of new techniques of donor heart preservation may contribute to the use of hearts from extended criteria donors, thereby expanding the total donor pool.

Luminal solutions protect mucosal barrier during extended preservation

BACKGROUND

Mucosal barrier injury during intestinal preservation (IP) and transplantation favors life-threatening infections. Luminal delivery of solutions containing amino acids or polyethylene glycols (PEGs) may improve preservation results and reduce this injury. We tested if solutions containing glutamine and PEG influence the mucosal injury.

MATERIALS AND METHODS

Rat intestines were perfused and stored in Viaspan-University of Wisconsin solution. Before IP, a PEG 3350 solution was introduced intraluminally alone (group 1) or supplemented with 40 mmol/L L-glutamine (group 2). Controls underwent vascular flush alone (group 3). Preservation injury was evaluated after 8, 14, and 24 h by histology and goblet cell count. Tight-junction proteins zonula occludens-1, claudin-3, claudin-4, and caveolin-1 were studied by immunofluorescence. Maltase and caspase-3 activity were also analyzed.

RESULTS

Group 1 showed mild edema at 8 h and mucosal disruption by 24 h; these features were greatly improved in group 2 where continuous mucosa was found after 24 h of IP. Intestines in group 3 did worse at all time points with subepithelial edema (Park/Chiu grade 3) and marked goblet cell depletion; caspase-3 activity was lowest in group 2. Tight-junction proteins varied continuously during IP; zonula occludens-1 expression and colocalization with claudins decreased significantly in group 3 but not in other groups. Claudin-3 was distinctly localized in the membrane, but stained diffuse, cytoplasmic at later time-points. Claudin-4 changed to a cytoplasmic granular pattern. No caveolin-1 colocalization was observed.

CONCLUSIONS

Luminal PEG and glutamine delay epithelial breakdown and preserve several important mucosal features during extended IP.

Amifostine enhances the antioxidant and hepatoprotective effects of UW and HTK preservation solutions

AIM: To investigate whether amifostine contributes to the antioxidant and cytoprotective effects of histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin (UW) preservation solutions.

METHODS: Forty-eight Sprague Dawley male rats were equally divided into six groups: (1) ringer Lactate (RL) group; (2) RL + amifostine (RL + A) group; (3) HTK group; (4) HTK + A group; (5) UW group; and (6) UW + A group. Rats in the RL + A, HTK + A and UW + A groups were administered amifostine intraperitoneally at a dose of 200 mg/kg prior to laparotomy. The RL group was perfused with RL into the portal vein. The RL + A group were perfused with RL into the portal vein after amifostine administration. The HTK group received an HTK perfusion while the HTK + A group received an HTK perfusion after administration of amifostine. The UW group received a perfusion of UW, while the UW + A group received a UW perfusion after amifostine administration. Liver biopsy was performed to investigate histopathological, immunochemical [transferase mediated dUTP nick end labeling (TUNEL), inducible nitric oxide syntetase (iNOS)] and ultrastructural alterations. Biochemical alterations were determined by examining levels of alanine aminotransferase, alkaline phosphatase and nitric oxide in the perfusion fluid.

RESULTS: Pathological sinusoidal dilatation and centrilobular hydropic alteration were significantly lower in the groups that received amifostine prior to preservation solution perfusion. Although the best results were obtained in the UW + A group, we did not observe a statistically significant difference between the UW + A and HTK + A groups. iNOS grades were significantly lower in the amifostine groups 12 h after treatment. When the amifostine groups were compared against each other, the iNOS grades obtained from the UW + A and HTK + A groups were similar while the RL + A group had a much poorer score. TUNEL assays demonstrated a lower apoptosis ratio in the amifostine groups than in the non-amifostine groups 12 h after treatment. No statistically significant difference was observed between the UW + A and HTK + A groups for apoptosis. Cellular ultrastructure was best preserved in the UW + A and HTK + A groups.

CONCLUSION: Here, we show that preoperative administration of a single dose of amifostine is sufficient to minimize the preservation damage in hepatic cells.