BACKGROUND:We aimed to observe the effect of hypotensive brain death on the donor liver and understand its pathophysiological mechanism in improved pig model. METHODS:The model was induced using the modified intracranial water sac inflation method in 16 Bama miniature pigs. Effects of hypotensive brain death on liver function and tissue morphology were evaluated via changes in liver function enzyme index, liver tissue alkaline phosphatase levels, hourly bile flow, and liver tissue pathology. Its pathophysiological mechanism was examined on the basis of changes in portal vein blood flow, hepatic artery blood flow, portal venous endotoxin level, and liver tissue cytokine levels. RESULTS:After model establishment, portal vein blood flow, hepatic arterial blood flow, hourly bile flow, and alkaline phosphatase content in hepatic tissue significantly decreased, and serum aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase levels significantly increased. Hematoxylin-eosin staining of liver tissue showed that after model establishment, hepatic tissue injury was gradually aggravated and hepatic cells were irreversibly damaged at 7 hours. Portal vein endotoxin levels significantly increased after brain death. Tumor necrosis factor α, interleukin 1, and endothelin 1 levels in liver tissues significantly increased at 3, 6, and 12 hours after brain death (P < .05), and hypoxia-inducible factor 1-α and nitric oxide levels significantly decreased (P < .05). CONCLUSIONS:Hepatic injury was progressively aggravated under hypotensive brain death. The mechanism of donor liver injury under hypotensive brain death may involve low liver perfusion, release of intestinal endotoxin and inflammatory factors (eg, tumor necrosis factor α and interleukin 1), decreased hypoxia-inducible factor 1-α, and endothelin 1 and nitric oxide imbalance.
The rat orthotopic liver transplantation model with extremely short anhepatic phase was established to study its protective effect on the recipients and graft. One hundred fifty adult male Wistar rats were randomly divided into three groups: group A (n = 30), using magnetic rings for the suprahepatic vena cava reconstruction; group B (n = 30), using 7/0 Prolene sutures for suprahepatic vena cava running anastomosis as control; and a sham-operated group (n = 30) as a blank control group. The changes in liver enzyme, serum creatinine, endotoxin, and cytokine levels and histopathology were recorded. The serum creatinine, potassium, alanine transaminase, and alkaline phosphatase levels at different points in time in group A were lower than those in group B (P < .05). The level of portal vein blood endotoxin in group A was significantly lower than that in group B at each point (P < .01). At the same time, all the cytokines in group B were higher than those in group A, and the two groups were higher than those in the sham operation group. The mean levels of tumor necrosis factor-α (TNF-α), interferon-γ, (IFN-γ), and interleukin-1ß (IL-1ß) at 3 hours were higher than at 6 hours in group A. IL-10 and tissue inhibitor of metalloproteinase-1 (TIMP-1) were all higher at 3 hours in groups A and B. Levels of monocyte chemotactic protein-1, L-selectin, and TIMP-1 in group A and IL-10, monocyte chemotactic protein-1, L-selectin, and TIMP-1 in group B were higher in blood than in the liver. Levels of TNF-α, IFN-γ, IL-1, IL-10, and intracellular adhesion molecule-1 in group A and TNF-α, IFN-γ IL-1ß, and intracellular adhesion molecule-1 in group B were higher in the liver than in blood. We conclude that the extremely short anhepatic phase has protective effects on recipients and grafts in rat liver transplantation because it is related to alleviating ischemia-reperfusion injury and reducing the endotoxin release.
Objective: To investigate the inhibitory effect of migration-inducing gene-7(Mig-7)interfered with retrovirus-mediated RNA(shRNA)combined with recombinant human endostatin(ES)on the growth and metastasis of subcutaneous xenograft of human hepatoma cells in nude mice. Methods: Two Mig-7-mRNA oligonucleotide sequences(Mig-7-shRNA-1 and Mig-7-shRNA-2)and one sequence as a negative control(Mig-7-shRNA-N)were designed. The specific Mig-7-shRNA recombinant retrovirus expression vector plasmid was constructed and used for the transfection of human hepatoma MHCC-97H cells with high expression of Mig-7. The subcutaneous xenograft tumor model of human hepatocellular carcinoma(HCC)in nude mice was established, and according to the condition of transfection and administration, the nude mice were divided into pSIREN-M1 group, pSIREN-MN group, ES group, and pSIREN-M1+ES group. The xenograft tumor volume, mass, and metastasis were compared between groups. Immunohistochemistry was used to observe the formation of vasculogenic mimicry(VM)in xenograft tumor and the difference in tumor microvascular density(MVD), and Western blot was used to measure the expression of Mig-7 and vascular endothelial growth factor(VEGF)in each group. A one-way analysis of variance was used for comparison between groups, and the Fisher's exact test was used for comparison of continuous data between groups. Results: Compared with the pSIREN-MN group, the pSIREN-M1 group had significantly lower xenograft tumor volume, mass, and metastasis rate, Mig-7 expression, and formation of VM(P < 0.05), as well as significantly higher VEGF expression and MVD(P < 0.05). Compared with the pSIREN-MN group, the ES group had significantly lower xenograft tumor volume, mass, and metastasis rate, VEGF expression, and MVD(P < 0.05), as well as significantly higher Mig-7 expression and formation of VM(P < 0.05). Compared with the pSIREN-M1 group and the ES group, the pSIREN-M1+ES group had significantly lower xenograft tumor volume, mass, and metastasis rate, Mig-7 expression, formation of VM, VEGF expression, and MVD(P < 0.05). Conclusion: Mig-7-shRNA recombinant retrovirus combined with ES has a better inhibitory effect on the growth and metastasis of HCC xenograft tumor than Mig-7-shRNA recombinant retrovirus or ES alone. The anti-tumor angiogenesis therapy alone, which targets vascular endothelial cells in vivo, has a limited effect, since it may promote the formation of VM.