Bone Marrow Mesenchymal Stem Cells Combined With Dexamethasone In The Treatment Of Ulcerative Colitis Model Rat

BackgroundUlcerative colitis is an autoimmune disease and often repeated. The traditional treatment is sometimes effective for light and medium cases of IBD, but for the most severe cases, treatment options are very limited. In vivo bone marrow mesenchymal stem cells have been shown to give rise to different mesodermal cell lineages and can migrate to the sites of injury and inflammation. Bone marrow mesenchymal stem cells are easy to be isolated and expanded in vitroand and can differentiate into osteogenic, adipogenic and chondrogenic lineages under appropriate conditions. In recent years, there has been an increasing focus on bone marrow mesenchymal stem cells since they have great plasticity and are potential for therapeutic applications. The distribution of bone marrow mesenchymal stem cells in the body after vein transplantation and its combination with dexamethasone in the treatment of ulcerative colitis are rarely reported at home and abroad. This study inculd in vitro and in vivo experiments of bone marrow mesenchymal stem cells, fucus on the in vivo tracking and dexamethasone associating of bone marrow mesenchymal stem cells.Objective1. To explore the isolation, culture, characterization and staining of rat bone marrow mesenchymal stem cells and the establishing of ulcerative colitis model.2. To observe the distribution of reinfusing rat bone marrow mesenchymal stem cells in the ulcerative colitis model rats.3. To Evaluate the effects of the treatment when bone marrow mesenchymal stem cells associated with dexamethasone in rat ulcerative colitis model. Methods1. Bone marrow mesenchymal stem cells were isolated, cultured, characterized, stained.2. The rat ulcerative colitis model was established. The DAI was scored and the intestinal sample obtained by biopsy were stained by HE.3. Bone marrow mesenchymal stem cells from rats labeled by DiR were transfusion into the ulcerative colitis model rats through the tail vein. To observe the distribution of bone marrow mesenchymal stem cells in the body through the in vivo fluorescence imaging and preparation of frozen sections.4. The rat were randomly divided into five groups with treatment of bone marrow mesenchymal stem cells and dexamethasone. After treatment, serum was obtained in1,3,5days respectively, and intestinal sample was obtained in the4th day. The intestinal contents of D-LAC, DAO, GSH-PX, SOD were detected.Results1. The fluorescence imaging is observed in colon tissue through in vivo fluorescence imaging and frozen sections in vitro. The fluorescence imaging is observed mainly in the lung and liver through in vivo fluorescence imaging.2. Each time point serum D-LAC, DAO content in ulcerative colitis model is higher than in the normal control group. In4th days colon tissue GSH-PX, SOD activity in ulcerative colitis model was lower than in the normal control group.3. Apart from serum D-LAC of dexamethasone treatment group was no statistically significant with blank control group in the5th days, the serum D-LAC, DAO levels of dexamethasone combined with BMSCs treatment group, dexamethasone treatment group and BMSCs treatment group at each time point were lower than the blank control group and decreased gradually over time. The colon tissue GSH-PX, SOD activity of each treatment group is higher than the blank control group in4th days.4. The serum D-LAC, DAO levels of dexamethasone combined with BMSCs treatment group were lower than the dexamethasone treatment group and BMSCs treatment group at each time point. The colon tissue GSH-PX, SOD activity of dexamethasone combined with BMSCs treatment group is higher than the dexamethasone treatment group and BMSCs treatment group in4th days.Conclusion1. Bone marrow mesenchymal stem cells can be planted in the intestinal tissue of ulcerative colitis model rat, but the number is still very limited. And most cells stayed in the lung tissue and liver tissue. The possible mechanism is that the average diameter of Bone marrow mesenchymal stem cells are large, most of them remain in the microvascular of pulmonary at death and metabolism in the liver.2. Compared to normal rat, ulcerative colitis rat’s intestinal barrier function and the ability of anti-membrane lipid oxidation is low.3. Dexamethasone combined with BMSCs, dexamethasone alone, BMSCs alone both have a better therapeutic effect in rat with ulcerative colitis. Compared to dexamethasone alone and BMSCs alone, dexamethasone combined with BMSCs have rapider intestinal barrier function recovery and higher anti-membrane lipid oxidation function. Therefore the treatment effect of dexamethasone combined with BMSCs is better than that of examethasone alone and BMSCs alone in rat of ulcerative colitis.