Study On The Effect Of Cell Pyroptosis On Small Intestinal Injury In Brain Death

Objective1.To investigate whether the donor small intestinal tissue has the phenomenon of cell pyroptosis under the state of brain death.2.A preliminary study was conducted to determine whether the selective Caspase-1 inhibitor,HY-13205,has a protective effect on the small intestinal tissue of the donor in the state of brain death.To provide a possible theoretical basis for improving the quality of the donor organs.Methods1.Small intestinal tissues from brain-dead organ donors and small intestinal tissues from patients who underwent gastrointestinal anastomosis were collected.Morphological changes of each specimen were observed by HE staining.Immunohistochemistry was used to test the expressions of NLRP3,Caspase-1 and IL-1beta in the cells of each sample.Western blotting was used to test the expression of Caspase-1,a protein related to cell pyroptosis,in each specimen.2.Study on the pyroptosis of small intestinal tissue cells under brain death in rats: SD rats were randomly divided into 3 groups,6 in each group: brain death for 6h group(BD): brain death for 6h in rats;HY-13205 treatment group(HG): intraperitoneal injection of HY-13205 16mg/kg was performed 30 minutes before the induction of brain death,and the remaining operations were the same as those in the 6h group;Sham operated group(S): the balloon was not pressurized,and the other operations were the same as the brain death group for 6h.Morphological changes of each specimen were observed by HE staining.Immunohistochemistry was used to test the expressions of NLRP3,Caspase-1 and IL-1beta in the cells of each sample.Western blotting was used to test the expressions of NLRP3,Caspase-1 and IL-1beta,which are related to cell pyroptosis.Results1.Compared with HE staining of small intestinal tissues removed by gastrointestinal anastomosis in patients with gastric cancer,small intestinal tissues of brain-dead organ donors showed obvious infiltration of inflammatory cells,with villus shedding and sparse villi.In patients with gastric cancer,the villi of the small intestinal tissues were arranged neatly after the operation of gastrointestinal anastomosis.Immunohistochemical staining showed that the expression levels of NLRP3,Caspase-1 and IL-1beta in small intestinal tissues of brain-dead organ donors were higher than that of non-brain-dead organ donors.The results of western blotting showed that the expression of caspase-1 was higher in small intestinal tissues of brain-dead organ donors.2.HE staining showed that,compared with normal small intestinal tissues,the infiltration of inflammatory cells in small intestinal tissues under brain death was significantly increased,and the arrangement of small intestinal villi was disorganized,and the villi were shedding,and the villi were sparse and significantly increased.After the intervention with the Caspase-1 inhibitor HY-13205,compared with the brain death group,the infiltration of inflammatory cells was reduced and the destruction of small intestinal villi structure was reduced.According to the results of immunohistochemical staining,the expressions of Caspase-1 and IL-1beta in the cells of small intestine under brain death were significantly increased compared with those in the normal small intestine.After the intervention with the Caspase-1 inhibitor HY-13205,the expressions of caspase-1 and IL-1beta were decreased compared with those in the brain death group.According to the results of western blotting,the expression levels of Caspase-1,NLRP3 and IL-1beta in the small intestine were significantly higher than those in the normal small intestine under brain death.After the intervention with the Caspase-1 inhibitor HY-13205,the expression levels of the three proteins were lower than those in the brain death group.Conclusions1.Brain death can cause the cell pyroptosis of the donor small intestinal tissues.2.The selective Caspase-1 inhibitor,HY-13205,can reduce the occurrence of cell pyroptosis and the damage of small intestine under the state of brain death,providing a certain theoretical basis for further quality protection of donor organs.