Effects Of Bone Marrow Mesenchymal Stem Cell Transplantation On Inflammatory Response After Acute Myocardial Infarction

Objective: Bone marrow mesenchymal stem cells(BMSCs)process special immunological property. This study investigated the effect of BMSCs on myocardial inflammatory cytokines expression in swines after myocardial infarction to further analyze the mechanism of stem cells for myocardial infarction.Methods: 18 swines were randomly divided into three groups with 6 swines in each group. group A: control group; group B: DMEM injection group; group C: BMSCs injection group. The models of myocardial infarction were built by embolization of the left coronary artery using a gelatin sponge by Digital Subtraction Angiography (DSA). Swine models in group A weren't used gelatin sponge, swine models in group B were injected with DMEM via LAD after myocardial infarction models were succeeded, swine models in group C were injected bone marrow mesenchymmal stem cells (BMSCs) via LAD after myocardial infarction models were succeeded. Echocardiography examination was performed before surgery and 1 week and 4 weeks after surgery to measure ejection fraction, left ventricular fractional shortening, at the same time ,we measure left ventricular systolic pressure and left ventricular end diastolic pressure to assess cardiac function. Immunohistochemistry and Western blot were performed to investigate the injected cells and the expression of inflammatory cytokines [tumor necrosis factor (TNF)-α,interleukin (IL)-6; IL-10]. Results: 18 swines were included in final analysis, 4 weeks after surgery , Compared to injection of DMEM,the Ejection fraction[(22.41±3.43)%,(28.43±1.32)%,P<0.05]; Left ventricular fractional shortening[(15.75±1.99)%,(20.60±2.44)%,P<0.05]; Left ventricular systolic pressure[ (97.29±4.58)mm, (101.27±2.39)mm, P<0.05] of the group of injection BMSCs significantly increased, and Left ventricular end diastolic pressure [(44.17±3.60)mmHg, (37.50±1.87)mmHg, P<0.05.]significantly reduced. 2.Immunohisto- chemistry demonstrated that transplanted cells were found living in the hearts of the host.3.Compared to injection of DMEM, BMSCs reduced the expression of tumor necrosis factor(TNF)-αand interleukin(IL)-6,(P <0.05),and simultaneously increased the expression of IL-l0(P<0.05). Western blot showed the same results as immunohisto- chemistry.Conclusion: Transplantation of BMSCs down-regulated TNF-αand IL-6 expression and up-regulated IL-10 expression and inhibited the progress of ventricular remodeling in myocardial infarction swines.