Effects Of Different Concentrations Of Alendronate On Cementoblast Proliferation, Differentiation And Mineralization In Vitro

Objective:This study aim to evaluate the effect of different concentrations of ALN on thecell proliferation, differentiation and mineralization of OCCM-30,which to providethe evidence for the influence of ALN on repairing of orthodontic induced rootresorption.Method:This experiment were divided into seven groups.The cell which were addedALN with concentrations of1×10^-6、1×10^-7、1×10^-8、1×10^-9、1×10^-10、1×10^-11mol/Las experimental group,and without ALN as control group. Different concentrations ofALN were respectively applied on immortalized murine cementoblast cellline,OCCM-30,3-（4,5-Dimethylthiazol-2-y1）2,5-diphenyl tetrazolium bromide （MTT）was used to study the cell proliferation and growth curve changes;enzyme linkedimmunosorbent assay（Elisa） was used to study the cell ALP activity assay,and ARSdye for mineralized nodules contents was used to study the effect on the mineralizedmatrix formation of the cell.All data were analyzed by using SPSS Statistics V17.0software.Results:1. MTT results showed that:cells in each group entered the logarithmic growthphase in48hrs. Compared with control group, the OD value of OCCM-30exposed tothe ALN with the concentrations of10^-8mol/L、10^-9mol/L and10^-10mol/L wassignificantly increased in the third day, so did the OD value exposed to ALN withthe concentrations of10^-7mol/L、10^-8mol/L and10^-9mol/L. But the rest exposed toALN with the concentration at10^-6mol/L was decreased significantly in the forth day.The OD value of OCCM-30exposed to the concentration at10^-6mol/L wassignificantly decreased in fifth day. This difference in effect is of statisticalsignificance（P<0.05）. 2. Elisa results showed that: cementoblast being treated with differentconcentrations of ALN,the ALP activity of OCCM-30was promoted at higher andlower concentrations and inhibited at medium concentration. But the difference wastoo small to have any statistical significance（P>0.05）.3. ARS dye results showed that, compared with control group, the cementoblastbeing treated with different concentrations of ALN, the mineralized nodules contentswere promoted at medium concentrations and inhibited at higher concentration. ALNcan promote the formation of mineralized matrix nodules of cementoblast atconcentration of1×10^-9mol/L and inhibit at concentration of1×10^-6mol/L. Thedifference had great statistical significance（P<0.01）.Conclusion:1. Cementoblast treated with different concentrations of ALN shared the samegrowth trend and entered the logarithmic growth phase in48hrs. The effect of ALNon the proliferation of cementoblast is biphasic. ALN with the concentration of1X10^-9mol/L is most effective in promoting cell proliferation with1X10^-6mol/L willinhibit the cell proliferation.2. Cementoblasts have an activity in ALP, but no evident effect of ALN on ALPactivity of cernentoblasts was observed after their48hrs’ exposure to ALN withdifferent concentrations.3. ALN can promote the formation of mineralized matrix nodules ofcementoblast at concentration of1×10^-9mol/L and inhibit the formation ofmineralized matrix nodules at concentration of1×10^-6mol/L.