The Effects Of NVP-BHG712as Specific Inhibitor Of EphB4on Human Osteosarcoma Cell Line MG63in Vitro

During orthodontic tooth movement, the application of relatively low staticorthodontic forces allows teeth to be moved through the alveolar bone. These forcesare transmitted through the periodontal ligaments (PDL) to the alveolar bone andlead to bone remodeling. Strain leads to bone formation, while compression stressleads to bone resorption. With the expression of ephrinB2in PDLF andosteoblasts(OB) being found, EphB4-ephrinB2signaling has been showed to beinvolved in the regulation of bone homeostasis. The EphB4receptor is unique in theclass of EphB receptors as it exhibits specificity of ephrinB2. Specific EphB4kinaseinhibitor NVP-BHG712can be used to identify the role played by EphB4-ephrinB2signaling at tension sites in promoting osteogenesis during orthodontic toothmovement.Objective: To study the effects of NVP-BHG712as specific inhibitor of EphB4on the proliferation and alkaline phosphatase(ALP) activity of human osteosarcomacell line MG63in vitro. Lay foundation in the further studies of the role palyed byEphB4-ephrinB2signaling in bone remodelling during orthodontic tooth movement,which will contribute to improve the treatment strategy and provide theoretical basisfor more accurate and reasonable control of tooth movement.Methods: MG63were thawed and cultured in vitro, then inoculated into24-well plates (5×103/well). NVP-BHG712was add with concentrations of6.25ng/ml,12.5ng/ml,25ng/ml,37.5ng/ml and62.5ng/ml as experimental groups.No NVP-BHG712was add in blank control. MTT assay was used to test theproliferation of the cells on day1-3after adding NVP-BHG712in order to study itseffect on proliferation. ALP activity and protein content were evaluated on day1,3, 5and7after adding NVP-BHG712in order to study its effect on ALP activity.Statistical analysis was conducted by t test. P<0.05was statistically significant.Results: MTT assay showed that the number of cells were gradually increasing.On the3rd day when the concentration of NVP-BHG712was6.25ng/ml, the ODvalue measured was higher than the control group (P<0.05). There was no differencebetween other experimental groups and blank control group. Also, there was nodifference between the experimental group and blank control group in ALP activity(P>0.05).Conclusion:1.6.25ng/ml NVP-BHG712can promote the proliferation of MG63whileconcentration of12.5ng/ml,25ng/ml,37.5ng/ml and62.5ng/ml NVP-BHG712hasno effect on the proliferation of MG63.2. Concentration of6.25ng/ml,12.5ng/ml,25ng/ml,37.5ng/ml and62.5ng/mlNVP-BHG712has no effect on ALP activity of MG63.