Kupffer cell activation and endothelial cell damage after storage of rat livers: Effects of reperfusion

Abstract

Reperfusion injury characterized by loss of endothelial cell viability occurs after cold ischemic storage of livers for transplantation surgery. Here, ultrastructural changes in stored rat livers were examined by scanning and transmission electron microscopy. With increasing times of storage in Euro-Collins solution (4 to 24 hr) followed by 15 min of reperfusion at 37 degrees C, a sequence of structural alterations was observed involving endothelial and Kupffer cells. Widening of endothelial fenestrations occurred after 4 hr and progressed over 8 to 24 hr to retraction of cellular processes, ball-like rounding, sinusoidal denudation and ultrastructural derangements consistent with loss of cell viability. Kupffer cells exhibited progressive rounding, ruffling of the cell surface, polarization, appearance of wormlike densities, vacuolization and degranulation over a similar time course. By contrast, the structures of parenchymal and fat-storing cells were relatively undisturbed by cold storage and reperfusion. Alterations to endothelial and Kupffer cells were also studied as a function of time of reperfusion. After 24 hr of storage, endothelial cells showed retraction of cytoplasm before reperfusion that progressed quickly to loss of viability and denudation during reperfusion. Kupffer cell activation (ruffling, degranulation) during reperfusion was slower and occurred after deterioration of endothelial cells. Livers stored in Euro-Collins solution were also compared with livers stored in University of Wisconsin cold storage solution, an improved preservation medium for transplantation. University of Wisconsin solution provided better preservation of endothelial structure and markedly reduced parenchymal cell blebbing and swelling before reperfusion. University of Wisconsin solution also reduced Kupffer cell activation and release of lysosomal enzymes. In conclusion, endothelial cell deterioration followed by Kupffer cell activation occurred after increasing times of cold ischemic storage and reperfusion of rat livers. Both changes may contribute to the pathophysiology of graft failure caused by reperfusion-mediated storage injury.

Cytochrome P-450 content and activity after cold storage of rat hepatocytes in university of wisconsin and sodium-lactobionate-sucrose solutions

“…Conversely, subsequent warm culture, which mimicks warm reperfusion, induced a further 15% to 20% loss of cell viability at all preservation times. These two stages of cytotoxicity correspond to the results obtained for nonparenchymal cells in the isolated perfused rat liver 7 and reflects the two major stages of transplantation injury in humans. 1 In the present study, we have found that cold storage in SLS solution affords as good a preservation of gross cell viability as does UW solution, whether during simple cold storage or after rewarming.…”

“…5,6 Unlike other organs, transplantation injury in the liver is characterized by microcirculatory problems that are related mainly to the sensitivity of liver endothelial cells to cold preservation and rewarming. 1,5,7 Morphologically, they show retraction of cytoplasm (rounding up) during cold preservation that progresses toward loss of viability and denudation of the sinusoids after warm reperfusion. 7 Although hepatocytes appear to be the most resistant cell type to cold storage and rewarming according to morphological studies, 7 others, including our-selves, have shown that their metabolic and transport functions are perturbed.…”

“…1,5,7 Morphologically, they show retraction of cytoplasm (rounding up) during cold preservation that progresses toward loss of viability and denudation of the sinusoids after warm reperfusion. 7 Although hepatocytes appear to be the most resistant cell type to cold storage and rewarming according to morphological studies, 7 others, including our-selves, have shown that their metabolic and transport functions are perturbed. [8][9][10] Hence, very little is known about injury to the hepatocytes, and this work was performed to explore one possible aspect of such injury.…”

High mobility group box 1 protein as a marker of hepatocellular injury in human liver transplantation

“…Moreover, liver nonparenchymal cells, including tissue macrophages (Kupffer cells) and the sinusoidal endothelium, are sensitive to cold ischemia. 2,32 Although the cold ischemic time was short (median, 5 hours), active HMGB1 secretion during graft procurement and preservation may partly account for hepatic HMGB1 outflow during reperfusion.…”

Role of free radicals in liver diseases

“…Strong evidence indicates that KC (the resident macrophages of the liver) may cause hepatic injury in various disease processes, including cold [54] and warm [55] ischemic injury. Ischemia activates KC, which are the main source of ROS during the reperfusion period [53].…”