Involvement of Rho-kinase in cold ischemia-reperfusion injury after liver transplantation in rats.
BACKGROUND
Reperfusion of ischemic tissues is known to cause the generation of reactive oxygen species (ROS) with resultant tissue damage. However, the sources of ROS in reperfused tissues are not fully characterized. We hypothesized that the small GTPase Rho and its target effector Rho-kinase/ROK/ROCK are involved in the oxidative burst in reperfused tissue with resultant reperfusion injury.


METHODS
In an in vivo rat model of liver transplantation using cold ischemia for 12 hr followed by reperfusion, a specific Rho-kinase inhibitor, fasudil (30 mg/kg), was administered orally 1 hr before the transplantation.


RESULTS
Fasudil suppressed the ischemia-reperfusion (I/R)-induced generation of ROS after reperfusion (P<0.01) and also suppressed the release of inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1beta) 3 hr after reperfusion, resulting in a significant reduction of I/R-induced hepatocellular injury (P<0.05), necrosis, apoptosis (P<0.01), and neutrophil infiltration (P<0.0001) 12 hr after reperfusion. All animals receiving a graft without fasudil died within 3 days, whereas 40% of those receiving fasudil survived (P<0.001).


CONCLUSIONS
The present study demonstrates that Rho-kinase-mediated production of ROS and inflammatory cytokines are substantially involved in the pathogenesis of hepatocellular necrosis and apoptosis induced by cold I/R in vivo and that Rho-kinase may be regarded as a novel therapeutic target for the disorder.
Department of Surgery and Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan. satokos@surg2.med.kyushu-u.ac.jp
Satoko
S
Shiotani
Mitsuo
M
Shimada
Taketoshi
T
Suehiro
Yuji
Y
Soejima
Tomoharu
T
Yosizumi
Hiroaki
H
Shimokawa
Yoshihiko
Y
Maehara
D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D016207:Cytokines / Q000378:metabolism; D006085:Graft Survival / Q000502:physiology*; D047908:Intracellular Signaling Peptides and Proteins; D007511:Ischemia; D008099:Liver; D008102:Liver Circulation; D016031:Liver Transplantation / Q000473:pathology / Q000502:physiology*; D008297:Male; D023421:Models, Animal; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051381:Rats; D011914:Rats, Inbred BN; D017382:Reactive Oxygen Species / Q000378:metabolism; D015427:Reperfusion Injury / Q000201:enzymology*; D013997:Time Factors; D014185:Transplantation, Isogeneic; D054460:rho-Associated Kinases
D016207:Cytokines; D047908:Intracellular Signaling Peptides and Proteins; D017382:Reactive Oxygen Species; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases