Effects of sodium fluoride on matrix metal proteinases-13 mRNA and tissue inhibitor of metal protease-1 mRNA in rat bone tissue / 中国地方病学杂志

ABSTRACT

Objective To observe the expressions of matrix metal proteinases-13(MMP-13) mRNA and tissue inhibitor of metal protease- 1 (TIMP- 1) mRNA and analyse the molecular mechanism of bone matrix degradation in the progress of rat subchronic fluorosis. Methods Male Wistar rats were randomly divided into two groups according to body weight, i.e. sodium floride group and control group. Rats in the sodium fluoride group were given drinking water containing 150 mg/L F-, and the animals in the control group were given tap water. The animals were bred for 24 weeks. Every 4 weeks some rats were killed. The change of obsteoclst was observed by transmission electron microscope. The expression levels of MMP-13 mRNA and TIMP-I mRNA were analyzed by RT-PCR. Results The number of lysesome and the synthesis of lysosoma enzyme in osteeclast were decreased. The expression of MMP-13 mRNA was significantly increased(t=2.29,2.41,3.07,2.52, 3.15,2.22, P<0.05) in rats treated with sodium fluoride (1.87±0.67,1.87±0.75,1.90±0.73,1.93±0.86,1.88±0.61,1.84±0.53), compared with control group(1.24±0.39, 1.19±0.27,1.07±0.22, I. 15 ~ 0.17, 1.17±0.18, 1.20±0.62). The expression of TIMP-1 mRNA was significantly increased (t=2.69,2.19,2.68,2.46,2.43,2.96, P<0.05) in rats treated with sodium fluoride(1.89±0.77,1.70±0.85,1.61±0.82,1.81±0.84,1.70±0.74, 2.06±0.96), compared with control group (1.07±0.39,0.87±0.49,0.71±0.48,0.99±0.43,0.95±0.46,0.89±0.57). Conclusion High dose fluoride might persistently induce the expressions of MMP-13 mRNA and TIMP-1 mRNA and may be involved in bone turnover.