Effects Of Endothelial Progenitor Cells Conditioned Medium On Osteogenic Differentiation Of Adipose-derived Stem Cells

Background:Orthopaedic surgery is entering a new era,biological therapies are starting to complement and even replace traditional mechanistic solutions.MSCs became the cornerstone of this change,such as the treatment of femoral head necrosis through autologous bone marrow mesenchymal stem cells to become the most widely used cell therapy.But the bone marrow mesenchymal stem cells used in regenerative medicine so far have not proved to be a panacea.ADSCs may be a source of stem cells that are more widely available and resistant to physiological stress.ADSCs are also more abundant and easier to obtain than bone marrow mesenchymal stem cells in the body.However,the potential for osteogenic differentiation of mesenchymal stem cells remains an inevitable problem.Therefore,the purpose of our study is to further explore how to enhance the proliferation and differentiation potential of ADSCs.Objective : To explore influence of the SD rat bone marrow-derived endothelial progenitor cells conditioned medium(EPC-CM)on the proliferation and osteoblastic differentiation ability of adipose-derived mesenchymal stem cells(ADSCs).Methods:In vitro,isolation,culture and identificated adipose mesenchymal stem cells and endothelial progenitor cells(EPCs).EPC-CM was devided into three different concentrations:0% EPC-CM group(the control group,cultured with LG-DMEM),50%EPC-CM group(cultured with 50% EPC-CM and 50% LG-DMEM)and 100%EPC-CM group(cultured with 100% EPC-CM).The proliferation activity of the ADSCs were tested by the CCK-8 method.Using alizarin red staining and ALP staining to qualitative analysis ADSC osteogenetic differentiation ability.Using quantitative test of ALP and calcium ion to anlysis ADSCs osteogenetic differentiation ability between three groups.Results:Immunofluorescence test showed that ADSCs high expression of CD90,and could differentiation into osteoblasts and adipocytes and chondroctes.The second generation of EPCs high expression of CD133 and VEGFR2.In a 96-well culture plate coated with matrix can form a tube-like structure,and it can specificity intake Dil-ac LDL and FITC-UEA-1.The proliferation activity of 50%EPC-CM group and100%EPC-CM group were significantly increased compared with control group,and associated with the concentration of EPC-CM(P < 0.05).Quantitative test of ALP after cultured 14 d and 21 d,the ALP activity of ADSCs in 50%EPC-CM group and100%EPC-CM group were higher than that in group A(P < 0.05).In the 14 th day and21 th day,calcium ions content in 50%EPC-CM group and 100%EPC-CM group were higher than that in control group(P < 0.05).Conclusions:EPC-CM can promote the proliferation and osteogenesis differentiation ability of ADSCs,which parted illustrates the mechanism of vascularization cells influence on bone formation.