Caspase-3 Expression and ALT, AST, and GGT Activity After 24 Hours of Porcine Liver Cold Storage, Depending on the Type of Transgenesis

BACKGROUND

Because of an insufficient number of human organs for transplantation, xenotransplantation may become an effective alternative. We aimed to analyze if the type of transgenesis has an influence on the hepatic caspase-3 expression, the enzyme that executes apoptosis as well as ALT, AST, and GGT activity after 24 hours of cold storage.

METHODS

The experiment was carried out on the 24 livers of Polish White Landrace pigs carrying human α1,2-fucosyltransferase and/or α-galactosidase (GAL) genes and livers without this genetic modification (control). Livers were perfused, stored for 24 hours in solution, and subsequently re-flushed. Hepatic concentration of the caspase-3 protein and its mRNA expression were measured just after the animal was killed as well as after 30 minutes of perfusion and after 24 hours of cold storage followed by 30 minutes of reperfusion. Caspase-3 mRNA level was detected with the RT-PCR method. Protein concentration (capsase-3 active and inactive) was assessed with the Western blotting technique. Kinetic methods were applied for the analysis of the ALT, AST, and GGT activity.

RESULTS

The highest increase of the ALT activity after cold storage was observed in the group with GAL transgenesis, whereas the GGT activity was highest in the unmodified livers. There was no difference in the caspase-3 expression and AST activity after cold storage as compared with the respective initial results (P = .57 and P = .97, respectively).

CONCLUSIONS

It appears that transgenesis does not aggravate ischemic injury of the liver.

Concentration of Tumor Necrosis Factor-α and Interleukin-1β in Isolated Porcine Liver Depending on Type of Transgenesis

BACKGROUND

Transgenic animals may serve as organ donors in human organ transplantation. However, the number of the studies addressing all doubts related to this issue is currently insufficient for the clinical application of this approach. The aim of this study was to analyze the hepatic tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) synthesis during a 24-hour cold preservation of the transgenic pig liver, depending on the type of transgenesis.

MATERIALS AND METHODS

The study was carried out on wild-type and transgenic pig livers with transferred human α1,2-fucosyltransferase (FUT) and/or α-galactosidase (GAL) gene (four groups; n = 6). Harvested livers were perfused for 30 minutes and stored for 24 hours in Biolasol (Biochefa) solution at 4°C with a subsequent 30-minute reperfusion (reflush). TNF-α and IL-1β concentrations were analyzed with an enzyme-linked immunosorbent assay. Perfusates were collected during the initial perfusion as well as after 24 hours of preservation and during the reperfusion. Tissue samples were harvested just after animal sacrifice, and after organ perfusion and reperfusion.

RESULTS

A decrease in TNF-α concentration in homogenates was noted after both perfusion and reperfusion in all experimental groups. In contrast, there was a significant decrease in IL-1β concentration in the group with combined human FUT and GAL transgenes. Concurrently, increases in TNF-α and IL-1β concentrations were observed in the reperfusion perfusates in all groups.

CONCLUSION

This study shows that IL-1β is synthesized in the ischemic livers of the transgenic animals with both human α1,2-fucosyltransferase and α-galactosidase transgenes. Further analysis is required to determine the importance of this observation.

Toll-like receptors 2 and 4 in pigs' kidneys early after autotransplantation procedure

OBJECTIVES

The aim of this paper was to evaluate mRNA expression of Toll-like receptors 2 (TLR2) and 4 (TLR4) and the adaptor protein myeloid differentiation primary-response protein 88 (MyD88) in pigs' kidneys 14 and 30 days after autotransplantation.

METHODS

The research was conducted on 12 animals that underwent left renal transplantation procedure with further standardized rinsing with Biolasol solution and 24 hours' storage in 4°C; subsequently the kidneys were implanted in the right retroperitoneal space after right-side nephrectomy. Six randomly chosen animals (group I) were under observation for 14 days, the other 6 (group II) for 30 days. After these observation periods, the animals were killed and 4-g samples were collected from the renal cortex and medulla.

RESULTS

Expression of mRNA in homogenates of collected samples were determined with the use of reverse-transcription polymerase chain reaction analysis. Obtained results in both groups, presented in relation to GAPDH, were compared with the use of Mann-Whitney U test. Stable graft function was observed in all animals from the 2nd day after the procedure. TLR2 in group I reached the mean value of 3.64 and was statistically significantly higher than in group II (2.19). Inverse proportion was observed in case of mRNA for TLR4: group II presented 2 times higher value than group I (0.25 vs 0.11). Similarly, significant difference was observed in MyD88 (group I, 0.067; group II, 0.45).

CONCLUSIONS

At 14 days after autotransplantation of a pig kidney, mRNA expression for TLR2 is dominant; later, expression increases for TLR4 and MyD88.

Comparison of endothelial nitric oxide synthase and endothelin-1 levels in kidneys removed from living pigs after cardiac arrest and brain death

OBJECTIVES

The aim of this paper was to describe differences between levels of endothelial nitric oxide synthase (NOS-3) and endothelin-1 (ET-1) in swine kidneys removed from living donors (group I) and after inducing brain death by brain herniation (group II) and cardiac arrest (group III).

METHODS

Each group consisted of 3 animals who underwent dual renal removal procedure; kidneys were further rinsed according to standardized procedure with Biolasol perfusion liquid, stored for 24 hours (4°C), and rinsed again. Renal specimens of 4 g mass, including renal cortex and medulla, were collected before and after perfusion (times 0 and 1), after 12 hours (time 2), and after reperfusion (time 3). Enzyme-linked immunosorbent assay was used to describe levels of NOS-3 and ET-1 in collected tissues homogenates. Mann-Whitney U test was used to compare results in groups in relation to total protein content (ng/mg), and the correlation between the 2 substances was measured with the use of Spearman rho.

RESULTS

Group I presented low and stable levels of NOS-3 in all time intervals (averages, 0.73, 0.99, 0.52, and 0.89, respectively). Level sof ET-1 were similar (0.87, 0.63, 0.69, and 0.86, respectively), and significant correlation between levels of the 2 substances was observed. Increased levels of NOS-3 (1.89 and 1.86) and ET-1 (1.38 and 1.49) were observed directly after removal in groups II and III and further maintained during organ storage. No correlation in group I was observed, and after perfusion significantly lower level of NOS-3 was observed in kidneys removed after brain death in relation to group III (1.77 vs 2.60).

CONCLUSIONS

The lowest and stable levels of NOS-3 and ET1 during storage were observed in kidneys removed from living donors. Levels of analyzed substances in this group showed correlation in subsequent time intervals.

Adrenaline and dopamine in porcine livers after cold preservation with University of Wisconsin histidine-tryptophan-ketoglutarate, prolactin-modified histidine-tryptophan-ketoglutarate solutions

INTRODUCTION

Hepatic ischemia-reperfusion injury remains a significant factor influencing early liver graft function. The aim of this study was to assess the impact on hepatic ischemia as reflected by catecholamine concentrations of different methods of organ preservation.

MATERIALS AND METHODS

Catecholamine levels were measured in 24 (n=6/group) pig livers, which underwent 30-minute warm ischemia followed by 30-minute perfusion and subsequent cold storage for 12 hours. For perfusion and preservation, we used University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK), HTK-modified with prolactin (PRL) or Ringer's solutions. Dopamine (DO) and adrenaline (ADR) concentrations in liver venous effluents were assayed using a radioimmunological method after 30 minutes of perfusion and following 12 hours of preservation.

RESULTS

DO and ADR levels were higher after 12 hours preservation compared to 30 minutes of perfusion. HTK produced an increase of over 100%. Addition of PRL (20 IU/L) did not affect DO and ADR levels after 30 minutes of perfusion, but significantly decreased their concentrations at 12 hours of preservation. After UW perfusion and preservation, we observed a 10% increase in catecholamine levels as compared with postperfusion values. Preservation with Ringer's solution demonstrated significantly higher DO and ADR levels compared with other solutions.

CONCLUSION

Catecholamines are present in the liver after 30 minute of perfusion and 12 hours of cold storage. The increased levels after 12 hours of preservation may be due to their release from intracellular spaces (as a controlled process or as a result of necrosis). It may play a crucial role in reperfusion injury, which, in turn, may explain the mechanism of no-reflow phenomenon.