Effect Of The Pluripotent Stem Cell-Derived Cardiac Myocytes Salvage Rat’s Infarcted Myocardium

ObjectivesMyocardial infarction is one of the primary diseases that threaten human health and has a serious impact on public health.Once the myocardium is damaged by infarction,the myocardium lacks the ability to regenerate and is replaced by fibroblasts,resulting in scar formation,ventricular remodeling,and dysfunction,which ultimately leads to irreversible heart failure.Therefore,how to reduce the necrotic myocardial cells in the infarct area,fundamentally saving the necrotic myocardial and improving the function of myocardium is the challenge for the treatment of ischemic heart disease.The success of human induced pluripotent stem cells(hiPSCs)has brought hope for breakthroughs in regenerative medicine.In recent years,As the technology for iPSCs to differentiate into cardiomyocytes in vitro continues to mature,iPSCs and induced pluripotent stem cell-Cardiomyocytes(iPSCs-CMs)have been widely used in drug toxicity screening and Research on disease models.In the treatment of myocardial infarction disease models,iPSCs and iPSCs-CMs have played a positive role and have a good effect on improving the function of myocardium,but the mechanism of action is not yet fully clear,and the main point of view is the paracrine mechanism,The release of some cytokines through paracrine plays the role of anti-inflammatory,anti-apoptosis,anti-fibrosis,promotes cell migration and promotes angiogenesis etc.,rescues damaged myocardial cells in the area of myocardial infarction,thereby improving myocardial function.In this experiment,hiPSCs were induced to differentiate into cardiomyocyte-like cells,and the obtained hiPSCs-CMs were transplanted into the infarcted area around myocardial infarction to explore the effect of induced pluripotent stem cell-derived cardiomyocyte transplantation on improving cardiac function in myocardial infarction rats,and Initially explore its mechanism of action.Methods1.The hiPSC-CMs were obtained by hiPSC directional differentiation,and were identified by morphology and cardiomyocyte field potential detection.2.SD male rats were randomly divided into three groups: sham group,PBS control group and hiPSC-CMs treatment group(n = 10 / group).The left anterior descending coronary artery(LAD)of the rat was ligated to prepare a rat model of myocardial infarction.After 30 minutes of myocardial infarction,for hiPSC-CMs group,a 60-ul mixture containing cells and PBS at a 1: 1 ratio was evenly transplanted into 4 points around the peripheral area of myocardial infarction in rats,while the PBS group was transplanted with equal amount of PBS.On day 3rd,14 th,and 28 th after transplantation,the left ventricular ejection fraction(LVEF)and left ventricular Fraction Shortening(LVFS)of rat heart were detected by echocardiography to evaluat hiPSC-CMs improving effect on cardiac function in rats with myocardial infarction;on 28 th day after cell transplantation,TTC staining was used to observe the area of myocardial infarction;Immunohistochemistry was used to detect CD31 and CXCR4 protein expression in rat heart tissue;HE staining was used to observe infarct Myocardial cell morphology changes.Results1.The differentiated hiPSC-CMs were beating,and the microelectrode array chip technology Axion Bio Systems was used to simulate the electrocardiogram signals to detect the field potentials of the hiPSC-CMs,showing the periodic field potential signals of the hiPSC-CMs were similar to the signals of the human electrocardiogram.2.Echocardiography showed that on the third day after transplantation,the LVEF and LVFS of the CMs group were slightly different than those of the PBS group,but the difference was not statistically significant.The LVEF and LVFS of rats in CMs group and PBS group were significantly lower than those in sham group.On day 14 th and 28 th after transplantation,the LVEF and LVFS of the hiPSC-CMs group were higher than those of the PBS group.TTC staining results showed that the myocardial infarction area in the hiPSC-CMs group was reduced compared with the PBS group.Immunohistochemistry showed that the expression of CD31 and CXCR4 in the peripheral area of infarction in the hiPSC-CMs group was higher than that in the PBS group.ConclusionThe results of this experiment show that hiPSC can be successfully differentiated into hiPSC-CMs;after the transplantation of hiPSC-CMs,it can reduce the area of myocardial infarction in rats and improve the myocardial function of myocardial infarction rats by promoting angiogenesis and cell migration.