Résumé
Objective To explore whether hyperbaric oxygen could enhance the effects of the transplanted stem cell on treating myocardial infarction rats.Methods A total of 70 Sprague-Dawley (SD) Rats was randomly divided into four groups,sham operated,acute myocardial infarction (AMI),mesenchymal stem cells (MSCs) (Stem Cell Transplanting),and hyperbaric oxygen (HBO) + MSCs group,respectively.Myocardial infarction rat model was established,hyperbaric oxygen treatment was carried out every day at the first to 30 day after AMI.Human umbilical cord Wharton jelly mesenchyme cell was transplanted at the third day after AMI.The densities of polymorphonuclear neutrophils and macrophages in the infracted border zones and in the infarcted area of heart were determined with hematoxylin and eosin (HE) staining.The cardiac function was assessed with M-mode transthoracic echocardiography,in vivo.Results (1)Compared to MSCs group,the stem cell proliferation and survival rates were increased significantly at the forth week (276.6 ±73.8 versus 20.5 ± 12.3,P ＜0.01).(2)Compared to the AMI and MSCs groups,the infracted area and the number of inflammatory cell infiltration were significantly reduced in HBO alone and MSCs + HBO groups.(3) Compared to the AMI group,the cardiac function was significantly improved at the different degree in the other three groups;among these groups,cardiac function was significantly improved in the MSCs + HBO group (P ＜0.01),except for the volume of end-dilation (P ＞0.05).Conclusions Hyperbaric oxygenation could significantly promote the proliferation and survival rate of stem cells,and improve the cardiac function.Thus further enhance the effect of the transplanted stem cell on treating the infarcted heart.
Résumé
Objective To generate of human induced pluripotent stem cells from umbilical cord matrix cells(UMC).Methods Sox2 and Klf4 and Oct4 and c-Myc were transfected into UMC cells with retrovirus,and thcn UMC cells was reprogrammed to iPS cells.Gene expression was confirmed with RT -PCR and the integration was confirmed with cell karyotype.iPS cells were further validatcd with cell alkaline phosphatase detection and immunofluorescence staining,differentiating into teratomas in vivo and embryoid bodies in vitro.Results iPS cells were similar to embryonic stem cells (ES).The expression of Nanog,Oct4,Rex1 and Sox2 in iPS cells were higher than UMC cells,and Sox2,Klf4,Oct4,c-Myc silenced in iPS cells.Exogenous genes were inserted into the nucleus of iPS cells,which was confirmed by 1％ agarose gel electrophoresis.iPS ccll karyotype was normal,alkaline phosphatase activity increased,ES cell-specific proteins,including SSEA3,SSEA4,TRA-1-60,TRA-1-81 and Nanog,were expressed.iPS cells were differentiated into a teratoma in vivo and embryoid bodies in vitro.Conclusions iPS cells were similar to ES cells,which had pluripotency.