| Bone Marrow Mesenchymal stem Cells(MSCs)have potential of differetiating into various cell lineages. Cell therapy can be considered as a strategy aimed at replacing, repairing or enhancing the biological function of a damaged tissue or organs by means of autologous or allogeneic cell transplantation.MSCs have characters of originating conveniently, expanding easily, and no immunity. MSCs may be an ideal seed cell of tissue engineering and receive more and more attention. Researcher found that MSCs transplantation in ischemic heart diseases may regenerate functional myocardium within the infarcted region, and improve heart function. The mechanism of improving heart function was unclear. Littlewas known about effect of bone marrow mesenchymal stem cells transplantation on myocardium structure and function in rats with heart failure and the mechanism of improving heart function. Our research was including the following works: isolating, culturing and expanding MSCs in vitro; establishing MSCs cultured system; establishing heart failure rat models; transplantating MSCs in heart failure rats; detecting heart function by transthoracic echocardiography(TTE) technique; identifying MSCs differetiating into cardiomyocytes; studying the mechanism of improving heart function of rats with heart failure to apply MSCs in clinic in the future. Method:MSCs were isolated from thighbone and tibia of Wistar rats, purified by adheresion-screening method, and expanded in vitro. MSCs were labeled with DAPI(a kind of fluorescence dye) at 12~24 hours before cell transplantion. Intraperitoneal injection of doxorubicin established the heart failure rat models. Three group were divided randomly: heart failure roup(no surgery), control group (injected equivalent volume culture medium), and treat group( injected MSCs). (l~5)xl06MSCs were injected into left ventricular myocardium of rats with heart failure,.TTE technique detected heart function after operation. At eight weeks after operation, plasma and serum were isolated from blood of heart cavity. The hearts wereexcised for histology analysis to observe whether MSCs survived and differentiated into cardiomyocytes and their effect on myocardium structure. Il-6 and ET-1 were detected in plasma and serum by RIA in three groups. Results:1. MSCs in primary culture expand to form cell colonies in several days, when the cells were passaged 3-4 times, red blood cells were removed. MSCs can be used in experiment. MSCs were labeled with DAPI before transplantion, and the rate of labeling was 100%.2. After 8 weeks of intraperitoneal injection of doxorubicin, LVEF LVFS decreased 20-30% compared with normal group, HE staining showed that the swelling of cardiomyocytes and intercellular space was found and myocardium fibers cracked down. 54 rats with heart failure were established sucessfully.3. Total 18 rats with heart failure were transplanted MSCs. 8 rats among them survived from 2-8 weeks after operation. In control group 18 rats were injeted equivalent volume culture medium, and 9 rats among them survived from 2~8 weeks after operation.4. LVEF LVFS increased significantly at 2 weeks after operation in treat group compared with control group and heart failure group (p<0.001). At eight weeks, LVEF LVFS increased more significantly compared with control group and heart failure group (p<0.05) at two weeks and four weeks(p<0.001). LVSD , LVPWS and LVPWD decreased significantly in treat group compared with control group and heart failure group (p<0.05).5. HE staining showed that implanted MSCs labeled with DAPI survived and angiogenesis was identified in implantation site. The swelling of adjacent cardiomyocytes alleviated and intercellular space expanded.6. ET-1 increased more significantly compared with control group and heart failure group (p<0.05) at eight weeks and IL-6 had no change. Conclusion1 . Implanted MSCs in heart failure model may improved heart function by MSCs participating in the repairing and renewal of myocardium.2. Implanted MSCs in myocardium microenvironme...
|
PDF Full Text Request