ABSTRACT
Objective Comparatively studying the method,efficiency and anti-hypoxia ability of cardiomyocytes which are directionally induced from human embryonic stem cells and mouse embryonic stem cells in vitro so as to provide an experimental basis for further study of inducing the differentiation of embryonic stem cells into cardiomyocytes in vitro.Methods Human embryonic stem cells are induced into cardiomyocytes by suspension method which dosen't using inducersand adherence method which using inducers respectively.Mouse embryonic stem cells are induced into cardiomyocytes by hanging drop method which dosent using inducers and using inducer respectively.Staining the specific marker cTnT of cardiomyocytes by immunofluorescence.Comparing the time,percentage and beating frequency of cardiomyocytes by counting under the microscope.Using apoptosis-hoechst staining kit to detect the apoptosis ratio of beating cardiomyocytes which have been treated by hypoxia with 24 h.Results The group of hESC without inducers results in that the mean time days of appearing beating cardiomyocytes is (13.9 ± 0.9) days,the percentage is 20.8 ％ and the average frequency of beating is (63.8 ± 5.6) times/min.The group of hESC with inducers results in that the mean time days of appearing beating cardiomyocytes is (13.0 ± 1.1) days,the percentage is 66.7％ and the average frequency of beating is (63.0 ± 7.0) times/min.The group of mESC without inducers results in that the mean time days of appearing beating cardiomyocytes is (14.3 ± 1.0) days,the percentage is 12.5％ and the average frequency of beating is (80.2 ± 3.9) times/min.The group of mESC with inducers results in that the mean time days of appearing beating cardiomyocytes is (12.2 ± 1.2) days,the percentage is 81.3％ and the average frequency of beating is (79.9 ±7.7) times/min.Beating cardiomyocytes of each group are positive to cTnT staining.Different apoptosis ratio are detected of beating cardiomyocytes of each group.Conclusion The four methods can all successfully induce the differentiation of embryonic stem cells into myocardiocytes,and the adherent method of hESC induced with activin A + BMP4 is the first successful induction in China.The groups adding inducers improve the differentiation efficiency more significantly than the groups without adding inducers.Inducing mouse embryonic stem cells into cardiomyocytes is more simple and efficient compared with human embryonic stem cells.Without the presence of other protective factor,anti-hypoxia ability of cardiomyocytes induced from human embryonic stem cells is stronger and the beating time are longer in vitro compared with mouse embryonic stem cells.