Xanthine oxidoreductase and preservation injury in human liver transplantation.
BACKGROUND
Preservation injury is a major cause of primary graft dysfunction in liver transplantation (LT). Oxidative damage is considered to be the first event leading to graft damage. Xanthine oxidoreductase (XOR) and neutrophil activation, two sources of reactive oxygen species, could play a role in the development of graft dysfunction.


METHODS
We determined activities of XOR forms, polymorphonuclear elastase (PMN-E), aminotransferases, and hyaluronic acid in plasma of 20 patients undergoing LT. Samples were taken from the radial artery (RA) before the anhepatic phase; from the portal vein (PV) before reperfusion; from graft caval effluent (CE) at reperfusion; and from RA, PV, and the hepatic vein (HV) 10 and 90 min postreperfusion.


RESULTS
The graft, but not recipient bowel, released XOR into blood (XOR in CE, median, 61.2 mU/g protein [range, 1.9-160.4 vs. undetectable in PV before reperfusion). Circulating XOR was transformed from dehydrogenase to reversible oxidase (XOrev) (XOrev-to-XOR ratio, 48.1% in CE and 65.1% in HV 90 min postreperfusion). Neutrophil activation was detected in the recipients before reperfusion, and in liver at early post-reperfusion (median PMN-E was 0.85 microg/g protein [range, 0.01-1.58] in RA before the anhepatic phase; 2.22 microg/g protein [range, 0.20-5.88] in PV prereperfu-sion; and 3.60 microg/g protein [range, 0.48-6.78] in HV 10 min postreperfusion). XOR, but none of the other markers, was higher in the CE of patients with moderate primary graft dysfunction than in those with slight primary graft dysfunction.


CONCLUSIONS
XOR release and neutrophil activation are produced during LT, and they are potentially injurious mechanisms associated with this therapy.
Martí
Ramon
R
Biochemistry Department, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
Múrio
Enric
E
Varela
Encarna
E
Bilbao
Itxarone
I
Pascual
Carles
C
Margarit
Carlos
C
Segura
Rosa M
RM
D000328:Adult; D000368:Aged; D006801:Humans; D019272:Leukocyte Elastase / Q000378:metabolism; D008099:Liver / Q000201:enzymology / Q000293:injuries; D016031:Liver Transplantation / Q000009:adverse effects* / Q000276:immunology / Q000502:physiology*; D008875:Middle Aged; D018375:Neutrophil Activation; D009926:Organ Preservation / Q000009:adverse effects*; D014969:Xanthine Oxidase / Q000378:metabolism*
D014969:Xanthine Oxidase; D019272:Leukocyte Elastase