Rapamycin attenuates liver graft injury in cirrhotic recipient--the significance of down-regulation of Rho-ROCK-VEGF pathway

Am J Transplant. 2006 Apr;6(4):697-704. doi: 10.1111/j.1600-6143.2005.01231.x.

Abstract

To investigate whether rapamycin could attenuate hepatic I/R injury in a cirrhotic rat liver transplantation model, we applied a rat orthotopic liver transplantation model using 100% or 50% of liver grafts and cirrhotic recipients. Rapamycin was given (0.2 mg/kg, i.v.) at 30 min before graft harvesting in the donor and 24 h before operation, 30 min before total hepatectomy and immediately after reperfusion in the recipient. Rapamycin significantly improved small-for-size graft survival from 8.3% (1/12) to 66.7% (8/12) (p = 0.027). It also increased 7-day survival rates of whole grafts (58.3%[7/12] vs. 83.3%[10/12], p = 0.371). Activation of hepatic stellate cells was mainly found in small-for-size grafts during the first 7 days after liver transplantation. Rapamycin suppressed expression of smooth muscle actin, which is a marker of hepatic stellate cell activation, especially in small-for-size grafts. Intragraft protein expression and mRNA levels of vascular endothelial growth factor (VEGF) were down-regulated by rapamycin at 48 h both in whole and small-for-size grafts. Consistently, mRNA levels and protein expression of Rho and ROCK I were decreased by rapamycin during the 48 h after liver transplantation. In conclusion, rapamycin attenuated graft injury in a cirrhotic rat liver transplantation model by suppression of hepatic stellate cell activation, related to down-regulation of Rho-ROCK-VEGF pathway.

Publication types

  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Actins / genetics
  • Actins / metabolism
  • Animals
  • Down-Regulation
  • Gene Expression / drug effects
  • Graft Survival / drug effects*
  • Graft Survival / genetics
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism
  • Immunosuppressive Agents / administration & dosage*
  • Intracellular Signaling Peptides and Proteins
  • Liver / cytology
  • Liver / drug effects
  • Liver Cirrhosis, Experimental / surgery*
  • Liver Transplantation*
  • Male
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Sirolimus / administration & dosage*
  • Vascular Endothelial Growth Factor A / blood
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism
  • rho GTP-Binding Proteins / genetics
  • rho GTP-Binding Proteins / metabolism
  • rho-Associated Kinases

Substances

  • Actins
  • Immunosuppressive Agents
  • Intracellular Signaling Peptides and Proteins
  • Vascular Endothelial Growth Factor A
  • smooth muscle actin, rat
  • Protein Serine-Threonine Kinases
  • rho-Associated Kinases
  • rho GTP-Binding Proteins
  • Sirolimus