Intestinal injury following liver transplantation was mediated by TLR4/NF-κB activation-induced cell apoptosis.

Intestinal motility and barriers are often impaired due to intestinal congestion during liver transplantation. Intestinal bacteria and enterogenous endotoxins enter into the blood stream or lymphatic system and translocate to other organs, which can result in postoperative multi-organ dysfunction (MODF) and systemic inflammatory reaction syndrome (SIRS) severely affecting patient survival. However, the mechanisms underlying liver transplantation-induced intestinal injury remain unclear and effective therapies are lacking. Thus, the present study investigated whether these effects were associated with endotoxin-mediated apoptosis. Rat autologous orthotopic liver transplantation (AOLT) models were established to observe dynamic intestinal injuries at different time-points following reperfusion. Changes in the levels of endotoxins and the primary receptor, toll-like receptor 4 (TLR4), as well as its downstream signaling molecule, nuclear factor-κB (NF-κB) were all determined. Finally, immunohistochemistry and terminal deoxynucleotidyl transferase dUTP nick end labeling assays were conducted to detect caspase-3 expression and intestinal cell apoptosis, respectively. AOLT resulted in significant pathological intestinal injury, with the most serious intestine damage apparent four or eight hours following reperfusion. Furthermore, the levels of endotoxins and inflammatory cytokines, such as tumor necrosis factor-α and interleukin-6, peaked during this time period and gradually decreased to the normal level. Notably, TLR4 and downstream NF-κB expression, as well as NF-κB-mediated caspase-3 activation and intestinal cell apoptosis coincided with the intestinal pathological damage. Thus, the possible mechanism of post-liver transplantation intestinal injury was demonstrated to be associated with NF-κB activation-induced cell apoptosis.

Influence of Ketotifen, Cromolyn Sodium, and Compound 48/80 on the survival rates after intestinal ischemia reperfusion injury in rats.

BACKGROUND: Mast cells were associated with intestinal ischemia-reperfusion injury, the study was to observe the influence of Ketotifen, Cromolyn Sdium(CS), and Compound 48/80(CP) on the survival rates on the third day after intestinal ischemia-reperfusion injury in rats. METHODS: 120 healthy Sprague-Dawley rats were randomly divided into 5 groups, Sham-operated group (group S), model group (group M), group K, group C and group CP. Intestinal damage was triggered by clamping the superior mesenteric artery for 75 minutes, group K, C, and CP were treated with kotifen 1 mg.kg-1, CS 50 mg.kg-1, and CP 0.75 mg.kg-1 i.v. at 5 min before reperfusion and once daily for three days following reperfusion respectively. Survival rate in each group was recorded during the three days after reperfusion. All the surviving rats were killed for determining the concentration of serum glutamic-oxaloacetic transaminase(AST), glutamic pyruvic transaminase(ALT), the ratio of AST compare ALT(S/L), total protein(TP), albumin(ALB), globulin(GLB), the ratio of ALB compare GLB(A/G), phosphocreatine kinase(CK), lactate dehydrogenase(LDH), urea nitrogen(BUN) and creatinine(CRE) at the 3rd day after reperfusion. And ultrastructure of IMMC, Chiu's score, lung histology, IMMC counts, the levels of TNF-alpha, IL-1beta, IL-6 and IL-10 of the small intestine were detected at the same time. RESULTS: Intestinal ischemia-reperfusion injury reduced the survival rate. The concentrations of TP, ALB and level of IL-10 in intestine in group M decreased significantly while the concentrations of S/L, LDH and the levels of IL-6 and TNF-alpha in intestine increased significantly compared with group S (P < 0.05). Treatment with Ketotifen and CS increased the survival rate compared with group M (P < 0.05), attenuated the down-regulation or up-regulation of the above index (P < 0.05). Treatment with CP decreased the survival rate on the 3rd day after reperfusion compared with group M(P < 0.05). Group K and C had better morphology in IMMC in the small intestine and in the lungs than in group M and CP, although the Chiu's score and IMMC counts remained the same in the five groups(P > 0.05). CONCLUSION: Mast cell inhibition after ischemia prior to reperfusion and following reperfusion may decrease the multi-organ injury induced by intestine ischemia reperfusion, and increase the survival rates.