ABSTRACT
Objective To observe the influence of fluoride and aluminum on the expression of matrix metalloproteinase-13(MMP-13) in rat articular chondrocytes. Methods Original generation chondrocytes of rats was cultured and divided into fluoride group, aluminum group, fluoride plus aluminum group and control group. NaF and A1C13 at concentrations of 1 mmol/L and 2 mmol/L were administered to intoxicate the cells for 24, 48, 72 h respectively. Cells were extracted to undergo reverse transcription the polymerase chain reaction(RT-PCR) at different times to observe mRNA expression of MMP-13, and protein expression was detected by Western-blot. Results In 24 h, the content of MMP-13 mRNA in fluoride group(0.830±0.043), aluminum group(1.279±0.060) and fluoride plus aluminum group(0.983±0.028) was higher than that in the control group(0.707±0.026, P<0.05), and relative expression of MMP-13 mRNA in aluminum group was the highest. In 48 h, the content of MMP-13 mRNA in fluoride group (0.964±0.180), aluminum group (1.333±0.105) and fluoride plus aluminum group (0.915±0.137) was higher than that in the control group(0.660±0.055, P<0.05), and the relative expression in aluminum group was the highest. In 72 h, the content of MMP-13 mRNA in fluoride group(0.866±0.115), aluminum group(0.846±0.089) and fluoride plus aluminum group(0.967±0.196) had no statistical significance(P>0.05) compared with the control group(0.809±0.179). In 24 h, the content of MMP-13 protein in fluoride group(1.050±0.084), aluminum group(1.010±0.113) and fluoride plus aluminum group(0.977±0.202) had no statistical significance(P>0.05) compared with the control group(0.860±0.038). In 48 h, the content of MMP-13 protein in fluoride group(0.671±0.020), aluminum group(1.134±0.094) and fluoride plus aluminum group (0.923±0.087) was higher than that in the control group (0.647±0.025, P<0.05), but no significant difference being observed between groups (P>0.05). In 72 h, the content of MMP-13 protein in fluoride group(0.672±0.022), aluminum group(1.088±0.072) and fluoride plus aluminum group(0.772±0.030) was higher than that in the control group(0.577±0.026, P<0.05). It was the highest in the aluminum group, the intra-group difference had statistical significance(P<0.05). Conclusions Fluoride and aluminum damage chondrocytes to some extent, toxicity of aluminum itself is greater than fluoride and fluoride plus aluminum. Abnormal expression of MMP-13 can be observed in the chondrocyte damage process induced by fluoride and aluminum.