Efficacy of prostaglandin I2 analog on liver grafts subjected to 30 minutes of warm ischemia

Due to the fact that no effective conditioning agent for hemodynamically unstable donors exists, the number of suitable donors is limited. The efficacy of OP-41483, a stable analog of prostaglandin I2, as a conditioning agent of the liver was investigated in this study using pigs. OP-41483 was administered via the portal tributary for 10 min before 30 min of warm ischemia. Graft livers were procured after perfusion with OP-41483 in cold normal saline, then flushed with OP-41483 in Euro-Collins solution and placed in cold storage prior to orthotopic transplantation. OP-41483 was also administered intraportally for 120 min after reperfusion. Biochemical and histological studies, and survival rates were compared with a control group not given OP-41483 in an otherwise similar experimental protocol. The graft function recovered better in the OP group than in the control group, shown by the lactate values and lactate-to-pyruvate ratios. The marked congestion noted in the parenchyma of the control group livers was minimal in the OP group, verifying the microcirculatory effect of prostaglandin I2 by its vasodilatory and antithrombotic actions. These findings suggest that OP-41483 has some protective effect as a conditioning agent in liver transplantation, with timing of administration being crucial.

The effect of trehalose on human lung fibroblasts stored in euro-collins and low potassium dextran solutions

BACKGROUND

The research on lung preservation for transplantation is directed to synthesize a solution, in order to prolong the preservation period, thus avoiding the damage to lung tissues caused by ischemia. In recent years some in vivo experimental papers have been published, in which good results were obtained by adding trehalose, a non-reducing disaccharide able to stabilize the cell membrane, to the storage solutions.

MATERIALS AND METHODS

In this study we have evaluated the effects on human lung fibroblasts of commonly used storage solutions like Euro-Collins (EC) and Low Potassium Dextran (LPD), in which trehalose has respectively replaced glucose (T-EC) or was added (LPD-T). The cultures were incubated for 8 hours at 10 degrees C in standard and modified solutions.

RESULTS

The data relative to EC compared to EC-T showed that the total protein content and the rate of protein synthesis, that is in other words cell viability, are drastically compromised. Concerning LPD-T, compared to standard LPD, a slightly decrease of the total protein content and of the rate of protein synthesis in the cells incubated in the modified solution were observed. The reasons for these unexpected data are related to the hypothesis that during the ischemic period membrane stabilization is neither the main nor the only factor responsible for the cellular damage. Moreover the role of trehalose in preservation solutions, is still not clear and should be further investigated.

CONCLUSIONS

With the limits of the study of single cells in vitro, the advantages of trehalose containing solutions proved ineffective and toxic especially as for as EC-T is concerned.