新型双甲基丙烯酰季铵盐单体对基质金属蛋白酶活性的影响  

Inhibitory effect of a novel crosslinking quaternary ammonium methacrylates on matrix metalloproteinases

作　　者：刘宁[1] 李芳[1] 张凌[1] 陈宇江[1] 陈吉华[1] 

机构地区：[1]第四军医大学口腔医学院修复科,西安710032

出　　处：《中华口腔医学杂志》2013年第4期239-243,共5页Chinese Journal of Stomatology

基　　金：国家自然科学基金（81100772、81130078、30901695）;陕西省自然基金（2011JQ4020）

摘　　要：目的研究新型双甲基丙烯酰季铵盐单体对基质金属蛋白酶活性的影响，探索提高牙本质粘接耐久性的新方法。方法使用荧光试剂盒检测质量分数分别为1％、3％、5％和7％的双甲基丙烯酰季铵盐单体[2-甲基丙烯酰氧乙基-正十二烷基-甲基溴化铵（2-methacryloxylethyl dodeeylmethylam monium bromide，MAE-DB）]对游离型基质金属蛋白酶8（matrix metalloproteinase-8，MMP-8）活性的影响，用酶标仪每隔20min检测荧光值至3h，以试剂盒提供的抑制剂1，10-二氮菲作为抑制剂对照组。将24颗离体牙制备的牙本质试件完全脱矿后获得胶原纤维试件，通过随机数字表法分成3组（每组50个），分别浸泡于人工唾液、含7％MAE-DB单体的人工唾液以及含2％氯己定的人工唾液中，经冷热循环5000和10000次后，检测胶原纤维试件拉伸强度的变化，评价MAE-DB单体对结合型基质金属蛋白酶的作用。透射电镜观察冷热循环后各组胶原纤维试件的形态。结果1h3％MAE-DB单体对MMP．8活性的抑制百分比为99．53％，显著高于抑制剂对照组（95．71％）（P〈0．05）。冷热循环5000次和10000次后，含7％MAE．DB组胶原纤维试件的拉伸强度[分别为（10．66±2．12）和（8．89±1．89）MPa]分别显著高于人工唾液组[分别为（7．43±2．27）和（5．46±1．76）MPa]和含2％氯己定人工唾液组[分别为（9．34±2．53）和（7．67±2．20）MPa]（P〈0．05）。透射电镜显示7％MAE-DB组胶原纤维微观结构完整，而人工唾液组胶原纤维微观结构紊乱。结论双甲基丙烯酰季铵盐单体MAE-DB可有效抑制MMP-8的活性，保护胶原纤维，降低胶原纤维在老化过程中的酶解。Objective To evaluate the anti-matrix metalloproteinase （MMP） activity of a novel crossliuking quaternary ammonium methacrylates, 2-methacryloxylethyl dodecylmethyl ammonium bromide （MAE-DB）. Methods The effects of MAE-DB at different concentrations （1%, 3%, 5%, 7%） on soluble matrix metalloproteinase-8 （MMP-8） were investigated using fluorescent assay kit. Readings were taken every 20 min for 3 h. The 1, 10-phenanthroline provided by the assay kit served as control group. Demineralized dentin beams were randomly divided into three groups （n=50） and immersed in different solutions： artificial saliva, MAE-DB incorporated artificial saliva and chlorhexidine incorporated artificial saliva. After temperature cycling, the changes of ultimate tensile strength were measured to determine the effect of MAE-DB on the activity of matrix-bound endogenous matrix metalloproteinases. The morphology of dentin collagen fibrils in the three groups was observed via transmission electron microscopy （TEM）. Results MAE-DB could effectively inhibit the activity of soluble MMP-8. The inhibition percentage of 3% MAE-DB was 99. 53% after 1 h, and it was significantly higher than that of 1,10-phenanthroline （95. 71%, P 〈0. 05）. After temperature cycling, the ultimate tensile strengths of MAE-DB groups were significantly higher than those of the artificial saliva groups and the chlorhexidine groups （P 〈 0. 05）. TEM micrographs of MAE-DB group revealed that the microstructure of the collagen fibrillar was intact, while the fibrillar in the artificial saliva group was disrupted, indicating a protective function of MAE-DB on dentin collagen. Conclusions MAE-DB can inhibit theactivity of MMP and protect dentin collagen from enzyme degradation.

关 键 词：基质金属蛋白酶8 拉伸强度 胶原 季铵类化合物 

分 类 号：R783[医药卫生—口腔医学]