Expression Of Annexin A1in Rabbit Bone Marrow Mesenchymal Stem Cells During Their Early Differentiation Into Osteoblasts And Adipocytes In Vitro

Background:With the wide range of applications of mesenchymal stem cells (BMSCs) in clinical, BMSCs has become one of the hot research in seed cell. The mechanism of bone marrow mesenchymal stem cells differentiation in vitro is not clear, previous studies often focused on a number of bone morphogenetic proteins(BMP), and few of other genes, and there also few research in Annexin Al during BMSC differentiation. The methods previous researches on Annexin Al are always simple, thus, the functions in cells differentiation of this gene can not be fully explain. Our research aims to study the expression of Annexin Al during BMSCs differentiation comprehensively.Part one Culture and identification of rabbit bone mesenchymal stem cells in vitroObjection:Isolated and cultured a highly purity and stability BMSCs in vitro.Methods:Using the whole bone marrow method to isolated and cultured BMSCs, subcultured and purified the cells, identified its specific surface marker, detectived the activity of cell’s differentiation.Results:The growth and differentiation of BMSCs is stability, the expression of CD44and CD105were more than95%, while CD45was negative.Conclusions:The gowth of BMSCs was stability while isolated iva the whole bone marrow method, and cells were induced easely. Expression of annexin Al in BMSCs during their early differentiation into osteoblasts and adipocytesObjection:To investigate the expression of ANX Al in rabbit BMSCs during their differentiation into osteoblasts and adipocytes in vitro.Methods:(1)Each experimental cell group was treatmented with osteogenic or adipocytes differentiation medium separately, while the negative control BMSCs were cultured with medium only.(2)The total cellular mRNA was extracted after3,7,14days, and the expression of ANX Al mRNA was detected by Real-time fluorescent quantitative polymerase chain reaction (RT-PCR).(3)Cells growth, proliferation and apoptosis were dictated via MTT and cell-flow.Results:(1)Expression of ANX Al mRNA was exhibiting a trend towards a significant reduction after BMSCs exposure to osteoblasts inducer (3d2-△△CT=0.643±0.076,7d2-△△CT=0.862±0.028, P<0.01). In contrast, adipocytes groups was showing an up-regulation of ANX Al mRNA (3d2-△△CT=1.264±0.115,7d2-△△CT=1.860±0.045, P<0.01).(3)Osteogenic inducer can inhibit the growth of BMSCs to achieve an increase in apoptosis (P<0.01), while the adipogenic inducer had little effects on cell growth and apoptosis (P>0.05). Conclusions:(1) Osteogenic medium inhibit the cell’s growth, and can promote cell apoptosis;(2) Annexin Al may play an important role in regulation of BMSCs differentiation into adipocytes in vitro exclude the role of inducer. However, the association with osteogenic differentiation is uncertain.