Study Of Adipose Tissue-Derived Mesenchymal Stem Cells Transplantation For Rats With Dilated Cardiomyopathy

Dilated cardiomyopathy, a kind of frequently found cardiomyopathy, is commonly combined by congestive myocardial failure with unfavourable prognosis. ADMSCs have multiple differentiation potentiality. And after transplanting to the damaged cardiac muscle, ADMSCs can survival, proliferate, and differentiate into cardiac muscle cells, thus improving the function of the heart. Here our data provided experimental and theoretical bases for the treatment of dilated cardiomyopathy clinically by transplanting adipose tissue-derived mesenchymal stem cells.Objective:(1). To establish dilated cardiomyopathy models by injection (i.p) of adriamycin.(2).To isolate and induce Mesenchymal stem cells from adipose tissue of Rats, finally to make clear whether adipose tissue-derived mesenchymal stem cells can be used as tools for further investigation.(3).Transplanting allogeneic adipose tissue-derived mesenchymal stem cells into cardiac muscle of Rats. Identify the survival and differentiation state of ADMSCs.Compare the function and hemodynamic changes of the heart before and after ADMSCs transplantion.Contents and Methods:(1).Establish the model of dilated cardiomyopathy.Dilated cardiomyopathy (DCM) model was established according to the published methods with little improvements. Briefly, DCM models were made by injection (i.p.) of Adriamycin, a protocol avoiding of surgical treatment and inducing chronic congestive heart failure. Finally the models were evaluated by identifying the function of the heart and by pathological section analysis.(2).Collect adipose tissues and isolate, induce ADMSCs.The profiles of ADMSCs were finally identified by histochemistry using the antibodies against CD 13, CD34, CD44, CD45, CD 105. (3).Transplant induced ADMSCs into rats with DCM. The rats which received only culture medium were used as negative controls. Four weeks after transplantation, the functions of heart were compared between the experiment and control groups using ultraphonic and haemodynamics examination. Finally, animals were sacrificed and the hearts were collected. The survival and differentiation state of ADMSCs were examined under fluorescence microscope.Results:(1).The rats which die during DCM model establishment were excluded. All other survival animals showed slower weight increase or weight loss, depilating, depressing, canthus anabrosis (some of them) compare to those from control group. Five rats were randomly selected and were examined anatomically. Compare to rats from control groups, DCM rats showed the following differences: globularlly expanded heart, thinner wall, bigger cavus; pathological section showed muscle fiber hypertrophy, vacuolization within the cavus, increased fibrous tissue, and cytolysis in some local cardiac muscle cells. Comparable heart functional parameters indicated that two weeks after DCM, there are increased left ventricular end diastolic volume (LVEDV) and left ventricular end systolic volume(LVESV), decreased ejection fraction (EF) in the left ventricular, which indicating a decreased heart function.(2).Culture the adipose tissue-derived cells resulted in lots of helico-growing long spindle cell. After couple of passaging, cells showed emission form, many of them with usiform shape. Al these cells showed the positive expression of CD 13,CD44,CD 105 and negative expression of CD34,CD45,Ⅷfactor,HLA-DR,VWF, with the potential to differentiate into osteoblast, lipocyte and muscle cells. These cells can be continuously cultured in vitro and keep stable growth speed. The doubling time of these cells from 3rd to 8th generation is about 55 to 63 hours. The recovery rate of these cells is above 90% after 2 to 4 weeks liquid nitrogen frozen. (3).Four weeks after transplantation, DAPI labled ADMSCs can be found around the transplanting site. Meanwhile, immunohistochemistry analysis detected the DAPI positive and TnT negtive cells, which grows in the same way as that of cardiac muscle cells.Compare to control groups, left ventricular systolic pressure (LVSP), the maximum change ratio of left intraventricular pressure (±dp/dt_max), ejection fraction (EF) of left ventricular in ADMSCs transplantation group were all significantly increased (p<0.01), while left ventricular end diastolic volume (LVEDV), left ventricular end systolic volume(LVESV) and stroke volume(SV), were significantly decreased.Conclusions:(1). Adriamycin can be used to induce DCM model in rats which result in globularly expanded heart, thinner wall, decreased ejection fraction (EF), and weakened ventricle construction as examined by echocardiography. These data suggested that DCM model were successfully established. (2). ADMSCs induced from rat adipose tissue showed the potentials to differentate into different cells. Induced ADMSCs showed paracrine secretion activity and be easily cultured and passaged in vivo. And they also can be easily recovered after liquid nitrogen frozen. All these characters suggested that ADMSCs can be used as useful tools for further study. (3). Four weeks after ADMSCs transplation, LVESP.+dp/dtmax,-dp/dtmax,EF (%) were all significantly up-regulated, while LVEDP,LVEDV and LVESV all significantly decreased. These data indicated that ADMSCs transplation could markedly improve the contraction and diastole function of the heart, inhibit the expanding rearrangement of the ventricle under DCM. Our data here provided useful evidences for using ADMCs transplantation to treat DCM and other non-ischmic heart failure.