Effects Of Vascular Endothelial Growth Factor(VEGF)on Proliferation And Osteogenic Differentiation Of Human Placenta Derived Stem Cells(HPMSCs)

Objective and background:Dentition defect,deformity,dentition defect and maxil-lofacial deformity,caused by periodontal diseases,trauma,tumors,and congenital malformations are common and frequently occurring diseases.These diseases cause chewing,language,swallowing dysfunction,affecting people's mental health.In addition,it also causes a series of complications,such as tooth loosening,displacement,occlusal disorder,temporo-mandibular joint disease,and even damage to the digestive system,circulatory system and so on.Therefore,early and correct repair of these defects is essential for maintaining oral and general health.With the development of Prosthodontics and dental implant,the main methods to solve the problem of missing or missing teeth or teeth are dental restoration and planting.It is an important prerequisite to ensure that the oral cavity repair or implant can be carried outsmosmoothly.Alveolar bone loss and defect caused by long-term lack of teeth,periodontitis,trauma,congenital malformation and tumor surgery,systemic disease brings great difficulties to the oral rehabilitation or implant.In recent years,the emergence of bone tissue engineering may solve this problem.Traditional bone tissue engineering technology in the repair of large bone defects often has the occurrence of ischemic necrosis due to the lack of blood circulation in the center of the bone tissue.So,how can developed vascularization osteogenesis,became the central issue of the currently research.In this experiment,human placenta derived mesenchymal stem cells(HPMSCs)were used as seed cells,vascular endothelial growth factor(VEGF)was used as a cytokine.Human placenta derived mesenchymal stem cells(HPMSCs)derived from the abandoned placenta tissue,as the seed cells has many advantage,such as(1)adequate supply,(2)convenient,(3)not subject to ethical constraints(4)low immunogenicity.Vascular endothelial growth factor(VEGF)has a double effect on vascular formation and bone formation.However,the study found that the high concentration of VEGF can lead to vascular malformations,micro leakage and so on,which is not conducive to the formation of bone.Therefore,in this study,the effect of vascular endothelial growth factor(VEGF)on the cell proliferation and the ability of osteogenic differentiation of human placenta derived stem cells(HPMSCs)was observed by the combination of gradient concentration of VEGF and HPMSCs.Method:The human placenta derived mesenchymal stem cells(HPMSCs)were isolated and purified by the method of tissue fragmen-tation combined with trypsin digestion in vitro.Cultured to the third generation,the test was performed to prove that the extracted cells were human placenta derived mesenchymal stem cells(MSCs).(1)Observe the cell morphology and growth characteristics.The proliferation of the third generation cells was detected by MTT,and the cell proliferation was detected continuously for 8 days.(2)the third generation of cells were cultured in the adipogenic and osteogenic medium,respectively,oil red O staining and alizarin red staining after 2 weeks adipogenic induction and 3 weeks of osteogenic induction.(3)The third generation human placenta derived mesenchymal stem cells were randomly divided into two groups: experimental group and control group.In the control group without VEGF,the experimental group was divided into 3 groups according to the concentration of VEGF.Then use MTT assay two groups cell proliferation,when cultured at 3,5,7 days.At 1,3,5,and 7 days,the osteogenic differentiation ability of the cells were detected by I collagen ELISA kit and ALP kit.Result:1.MTT results showed that: With the cell culture time increased,the OD value becomes larger,and the growth curve was "S" type,accord with the characteristic of stem cells proliferation.2.Oil red staining and alizarin red staining showed lipid droplet and calcium nodules,showed that the separation and extraction of cells have the ability of adipogenic differentiation and osteogenic differentiation.3.MTT,ELISA,ALP showed that the proliferation and osteogenic ability of cells in the experimental group were significantly better than the control group,when the concentration of VEGF <100 ?g/L with the increase of the concentration the effect was enhanced when the concentration is 200?g/L had no significant difference compared to100?g/L.Conclusions:Vascular endothelial growth factor(VEGF)can promote the ability of human placenta derived stem cells(HPMSCs)on he proliferation and osteogenic differentiation.Within a certain concentration range,the effect is positively related to the concentration.However,with the increase of concentration,the effect was not significantly improved.