Role of necroptosis in intestinal injury induced by autologous orthotopic liver transplantation in rats

Abstract

Objective To evaluate the role of necroptosis in intestinal injury induced by autologous orthotopic liver transplantation (AOLT) in rats. Methods Twenty-four SPF adult male Sprague-Dawley rats, aged 10-12 weeks, weighing 250-280 g, were divided into 3 groups (n=8 each) using a random number table method: sham operation group (group S), AOLT group (group T) and necroptosis inhibitor necrostatin-1 group (group N). Necrostatin-1 1.0 mg/kg and the equal volume of dimethyl sulfoxide (DMSO) were intraperitoneally injected at 30 min before surgery in N and T groups, respectively.Blood samples were collected from the inferior vena cava at 6 h after opening the portal vein (at 6 h after the end of surgery in group S) for determination of serum diamine oxidase (DAO), D-lactic acid (D-LA) and intestinal fatty acid binding protein (I-FABP) concentrations by enzyme-linked immunosorbent assay.Rats were sacrificed after blood sampling, and the intestine was removed for examination of the pathological changes (with a light microscope) and for determination of malondialdehyde (MDA) contents and superoxide dismutase (SOD) activities (using a spectrophotometer), and the expression of receptor-interacting protein kinase-1 (RIPK1), RIPK3 and mixed lineage kinase domain-like protein (MLKL) in intestinal tissues (by Western blot). Intestinal damage was assessed and scored using Chiu′s scoring system. Results Compared with group S, the serum DAO, D-LA and I-FABP concentrations, MDA content and Chiu′s score were significantly increased, SOD activity was decreased, and the expression of RIPK1, RIPK3 and MLKL was up-regulated in group T (P<0.05). Compared with group T, the serum DAO, D-LA and I-FABP concentrations, MDA content and Chiu′s score were significantly decreased, the SOD activity was increased, and the expression of RIPK1, RIPK3 and MLKL was down-regulated in group N (P<0.05). Conclusion Necroptosis is involved in the pathophysiological process of intestinal injury induced by AOLT in rats. Key words: Liver transplantation; Intestine; Necrosis