摘要
目的研究在氟中毒引起氟斑牙时,氟对大鼠切牙细胞凋亡、天冬氨酸特异性的半胱氨酸蛋白水解酶-3(Caspase-3)和Caspase-8活力的影响。方法将20只健康成年SPF级雄性SD大鼠随机分为4组,分别为对照(蒸馏水)组和低(10 mg/L)、中(50 mg/L)和高(100 mg/L)浓度NaF染毒组,每组5只。采用自由饮水方式进行染毒,每只每日饮水量约为40 ml,连续染毒120 d。采用流式细胞术检测大鼠切牙细胞凋亡率和细胞增殖周期的变化,采用酶标仪检测Caspase-3和Caspase-8的活力。结果随着NaF染毒浓度的升高,大鼠切牙细胞的凋亡率以及Caspase-3和Caspase-8活力均呈明显的增高趋势(凋亡率:r=0.923 9,P<0.01;Caspase-3:r=0.966 6,P<0.01;Caspase-8:r=0.932 2,P<0.01)。大鼠切牙细胞凋亡率与Caspase-3和Caspase-8活力均呈显著的正相关(Caspase-3:r=0.798 3,P<0.05;Caspase-8:r=0.975 3,P<0.01)。与对照组比较,中浓度NaF染毒组大鼠切牙细胞G2/M细胞构成比下降,高浓度NaF染毒组S期细胞构成比下降,差异均有统计学意义(P<0.05)。各组大鼠切牙细胞G0/G1细胞构成比间比较,差异无统计学意义。各组大鼠切牙细胞DNA相对含量(DNA related content,DNARC)和细胞增殖指数(proliferation index,PI)间比较,差异均无统计学意义。结论 Caspase介导的细胞凋亡在氟斑牙形成过程中发挥重要作用。
Objective To explore the effects of sodium fluoride （NaF） on apoptosis, activity of caspase-3 and caspase-8 in rat incisor cells during dental ftuorosis. Methods Twenty SPF male SD rats were randomly divided into control,low,moderate and high dose fluoride groups,five rats in each group and treated with fluoride through drinking water at the doses of 0,10,50 and 100 mg/L sodium fluoride for 120 days,respectively. The average drinking water volume of per animal was approximately 40 ml/d. Cell apoptosis and cycle alterations were quantified by flow cytometry. Colorimetric assay was used to examine caspase-8 and caspase- 3 activity with enzyme-labelled meter. Results Apoptosis rate,caspase-3 and caspase-8 activities in rat incisor cells showed a significant increase in a dose-dependent manner （P〈0.01） , with relative coefficient of 0.923 9,0.966 6,0.932 2 respectively. The apoptosis rate displayed a close relationship with the activities of caspase-3 （r=0.798 3 ,P〈0.05） and caspase-8 （r=0.975 3 ,P〈 0.01）. NaF reduced the cell number of G2/M and S phase in cell cycle at the doses of 50 and 100 mg/L respectively,but failed to affect DNA relative content and proliferation index in incisor cells. Conclusion Apoptosis mediated by caspase activating pathway plays an important role in the formation and development of dental fluorosis in rats.
出处
《环境与健康杂志》
CAS
CSCD
北大核心
2011年第1期20-22,共3页
Journal of Environment and Health
基金
广东省医学科研基金(A2008331)
广东省自然科学基金(9151022401000003)
广东药学院师资队伍建设经费
