Study On The Proliferation And The Expression Of Collagen Type X Of Chondrocytes Exposure To Fluoride That Intervened By DKK1Recombinant Protein

Objective To investigate the effect of DKK1on the injury of joint in the fluoridebone injury and the feasibility of DKK1intervene in the early prevention andtreatment of joint injury in the fluoride bone injury. We establish the model of primaryculturing chondrocytes of rats exposed to fluoride in vitro, observe the changes onproliferation and the expression of collagen type X in the DKK1intervene before andafter.Methods The chondrocytes were collected from knee joint of rats viamechanical-enzyme digestion, cells were divided into one control group and fourfluoride exposure groups (5,10,20and40mg/L NaF). The proliferation activity ofcells were tested at different time (24,48,72and96h) by MTT and the expression ofCOL-10were tested by ELISA. Divided the cells under72h of fluoride exposure at10mg/L NaF into one non-intervention group and three intervention groups (1,2and4μg/L DKK1Recombinant protein PBS), the proliferation activity of cells and theexpression of COL-10were tested at12,24and36h.Results The results of MTT showed that the proliferation activity of the groups of5,10,20mg/L at24h, the groups of5,10,20mg/L at48h, the groups of5,10,20mg/L at72h and the group of10mg/L at96h were higher than that in control group, thedifferences are statistically significant (P<0.05). but the proliferation activity in40mg/L group at72and96h were significantly lower than that in control group (P<0.05).The expression of COL-10in all of groups were significantly higher than that incontrol group (P<0.01). Compare with group of5mg/L, there is no significantly differences among all the groups at24h (P>0.05), but group of10mg/L at48h(254.10±23.01) ng/L was significantly higher than group of5mg/L (230.36±12.50)ng/L (P<0.01), and groups of10,20and40mg/L at72and96h were significantlyhigher (P<0.01).Compare with control group, the concentration of DKK1had nosignificantly differences at24h (P>0.05), but in groups of10,20and40mg/L at72and96h were significantly lower (P<0.01).After intervention of DKK1recombinant protein, compare with thenon-intervention group, the proliferation activity of group C at12h, group B at24hand group C at36h were significantly lower (P<0.05), group A at36h wassignificantly higher (P<0.05).The concentration of COL-10had no significantlydifferences at12h (P>0.05), but lower than that in non-interventiongroup(246.26±12.41) ng/L,(248.43±12.72) ng/L in groups of B and C at24h(209.79±14.42) ng/L,(216.68±16.66) ng/L and36h (214.85±17.11) ng/L,(210.96±15.38) ng/L (P<0.01).Conclusion The lower dose fluoride exposure could promote the proliferation activityof chondrocytes, but suppressed in high dose. The proliferation activity and theexpression of COL-10of chondrocytes were promoted under fluoride exposure. Andthis condition could be resisted by the intervention of DKK1recombinant protein.This survey indicate that excess fluoride exposure could promote chondrosteosis viainhibiting the expression of DKK1and give a prompt that DKK1recombinant proteinintervene may effectually in the early prevention and treatment of joint injury in thefluoride bone injury.