The Effect Of Umbilical Cord Mesenchymal Stem Cells On Free Radials And Apoptosis Of Rat Intestinal Tissue With Radiation Injury

Objective:To investigate the effect of umbilical cord mesenchymal stem cells on free radials and apoptosis of rat intestinal tissue with radiation injury,and explore the treatment mechanism’s relationship with free radicals and cell apoptosis.Methods:The 36 healthy female SD rats, were divided randomly into 3 groups, the normal group, the irradiation group, the treatment group. each group have 12 rats.The normal group:don’t do the irradiation experiment, the 2nd days after the experiment,the rats were respectively injected with 1 ml physiological saline in tail intravenous; the irradiation group: the whole Abdomen receiving 9 Gy ionizing irradiation with 60 Co gamma ray, the 2nd days after the experiment,the rats were respectively injected with 1 ml physiological salinethe;the experimental group: the whole Abdomen receiving 9 Gy ionizing irradiation with 60 Co gamma ray,the 2nd days after the experiment,the rats were respectively injected with 1 ml physiological salinethe of a dose of 1×106 HUCMSCs. the Rats in each group after irradiation 7 days were killed and take the intestine and blood,observed the intestine tissue pathological changes under the light microscope,and to detect plasmic DAO content to know the small intestinal damage, through the colorimetric method to detect intestinal SOD activity、MDA content and NO content to know the changes of free radical content, TUNEL detect the cell apoptosis.Results:1.The plasma level of DAO:It is in the treatment group and the irradiation group that the plasma DAO content were all increased significantly compared with the normal group(P<0.05),and the plasma DAO content of the irradiation group was significantly higher than the treatment group(P<0.05).2.The intestinal MDA content:It is in the treatment group and the irradiation group that the intestinal MDA content were all increased significantly compared with the normal group(P<0.05),and the intestinal MDA content of the irradiation group was significantly higher than the treatment group(P<0.05).3.The intestinal SOD activity:It is in the treatment group and the irradiation group that the intestinal SOD activity were all decreased significantly compared with the normal group(P<0.05),and the intestinal SOD activity of the irradiation group was significantly lower than the treatment group(P<0.05).4.The intestinal NO content : It is in the treatment group and the irradiation group that the intestinal NO content were all increased significantly compared with the normal group(P<0.05),and the intestinal NO content of the irradiation group was significantly higher than the treatment group(P<0.05).5.The intestinal HE staining : It is in the treatment group and the irradiation group that small intestinal mucosa morphology and structure was damaged severely compared with the normal group,the thickness of small intestinal mucosa is uneven, the fluffy structure is incomplete,and the intestinal crypt lost normal structure.There are some changes in the submucosa,including vasodilation,congestion and inflammatory cells infiltration.Compared with the irradiation group,the radiation damage of the small intestinal mucosa pathological morphology and structure in the treatment group had shown some improvement.6.The cell apoptotic rate of small intestine:It is in the treatment group and the irradiation group that the cell apoptotic rate of small intestine were increased significantly compared with the normal group(P<0.05),and the cell apoptotic rate of the irradiation group was significantly higher than the treatment group(P<0.05).Conclusion:The umbilical cord mesenchymal stem cells can reduce the rat intestinal radioactive damage degree,its mechanism may be related to the promotion of free radicals scavenging ability and the inhibition of cell apoptosis.