The effects of circulating interleukin-8 and adhesion molecules on pulmonary dysfunction in pediatric orthotopic liver transplantation

Cytokine response to ischemia/reperfusion injury in an ex vivo perfused porcine liver model

BACKGROUND

We evaluated the degree of inflammatory response after ischemia/reperfusion injury by an extracorporeal normothermic autologous hemoperfusion of porcine livers.

MATERIALS AND METHODS

Livers explanted from 7 pigs were perfused extracorporeally at 39 degrees C with autologous blood. Serum samples were obtained hourly until 6 hours from the beginning of reperfusion and assayed for 9 different cytokines.

RESULTS

Significant elevations in interleukin 6 (IL-6) and IL-8 were noted following reperfusion (P < .001), with both demonstrating an increase which followed a sigmoid curve; other cytokines that were assessed showed no significant change.

CONCLUSIONS

The ex vivo model excludes the liver from the influence of external systemic factors such as hormones, the autonomic nervous system, and other regulatory molecules produced elsewhere in the body, allowing the response to the ischemia/reperfusion injury to be studied in isolation and in considerable detail. Although this study examined a relatively short period, the increases in only IL-6 and IL-8 suggested that these are important molecules in the early phase after reperfusion.

Change in free radical-related substances in plasma following ischemia-reperfusion in rat liver

In order to clarify the relationship between free radicals and liver injury due to ischemia-reperfusion, we investigated the dynamics of radical-related substances in the blood of rats after liver ischemia-reperfusion. Subsequent to 60 min of liver ischemia, the generation of reactive oxygen species (ROS) from polymorphonuclear leukocytes (PMNs) initiated by phorbol myristate acetate (PMA) and lipid peroxidation significantly increased 2 h after reperfusion and showed peak values at 8-10 h. These values returned to the control level 32 h after reperfusion. The levels of nitric oxide metabolites (NO(x), NO(2)(-)+NO(3)(-)) increased biphasically at 10 and 32 h during the period of reperfusion, but did not return to control levels. Cu,Zn-superoxide dismutase (SOD) levels increased immediately after 5 min of reperfusion and showed a peak value after 20 min. This increase diminished gradually and returned to the control level 10 h after reperfusion. Mn-SOD increased 2 h after reperfusion, and this level was maintained for 48 h. The levels did not show increases at the end of ischemia and were nearly identical to the pre-ischemia levels. These finding obtained from the dynamics of radical-related substances are considered very meaningful for investigating mechanisms in the pathogenesis of liver injury by ischemia-reperfusion, and are clinically important in liver transplantation.