胞壁酰二肽对人牙髓细胞分化影响的研究  

Effects of muramyl dipeptide on the differentiation of human dental pulp cells

作　　者：罗传霞[1] 张莉[1] 宋智[1] 秦伟[1] 林正梅[1] 

机构地区：[1]中山大学光华口腔医学院·附属口腔医院牙体牙髓病科·中山大学口腔医学研究所,广州510055

出　　处：《中华口腔医学杂志》2011年第7期412-416,共5页Chinese Journal of Stomatology

基　　金：国家自然科学基金（81070829）

摘　　要：目的探讨天然免疫受体核苷酸结合寡聚化结构域蛋白2（nucleotide—binding oligomerization domain-2，NOD-2）在深龋牙髓组织中的表达及NOD-2特异性配体胞壁酰二肽（muramyl dipeptide，MDP）对人牙髓细胞分化的影响。方法实时荧光定量聚合酶链反应（PCR）法检测深龋及健康人牙髓组织中NOD-2表达差异；1mg／LMDP刺激体外培养的人牙髓细胞0、2、6、12、24h，实时荧光定量PCR、蛋白质免疫印迹法及免疫荧光检测NOD-2基因及蛋白表达；不同质量浓度MDP刺激人牙髓细胞24h，蛋白质免疫印迹法检测24h后牙本质涎蛋白（dentin sialoprotein，DSP）的表达；0．1mg／LMDP作用于人牙髓细胞0、2、6、12、24h，检测不同时间点牙本质涎磷蛋白（sialophosphoprotin，DSPP）、骨钙蛋白mRNA及骨桥蛋白的表达。结果深龋牙髓组织中NOD-2mRNA相对表达量为（0．2610±0．0824），较健康牙髓组织（0．0024±0．0002）显著增高（P〈0．05）。实时荧光定量PCR及蛋白质印迹法结果显示NOD-2表达随时间上调，免疫荧光检测证实NOD-2蛋白表达于胞质。MDP质量浓度为0．1mg／L时DSP蛋白表达量最大（0．3782±0．0564），并随MDP质量浓度增加而下降；DSPP、骨钙蛋白mRNA表达呈时间依赖性，12h达最大值，24h后有所下降；骨桥蛋白表达量随时间上调。结论深龋牙髓组织中NOD-2表达升高，MDP与人牙髓细胞的分化相关。Objective To investigate the nucleotide-binding oligomerization domain-2 （NOD-2） gene expression in deep caries and the effects of NOD-2 agonist muramyl dipeptide （MDP） on the differentiation of human dental pulp cells（hDPC）. Methods NOD-2 gene level in deep caries and healthy pulp tissue was determined by real-time quantitative polymerase chain reaction （realtime-PCR）. Reahime- PCR, Western blotting and immunofluoreseenee were performed to evaluate NOD-2 gene and protein expression. Dentin sialoprotein（DSP） protein level was assessed when hDPC were challenged by different concentrations of MDP for 24 hours, and sialophosphoprotein （DSPP） , osteocalcin （OCN） mRNA and osteopontin（OPN） protein level were detected at different time points after incubation with 0. 1 mg/L MDP. Results NOD-2 mRNA level was higher in pulp tissue of deep caries （0. 2610 ± 0. 0824 ） than that in healthy controls （ 0. 0024 ± 0. 0002 ） , P 〈 0.05. The expression of NOD-2 gene and protein increased in a time denpendent manner upon stimulation with MDP. Immunofluorescence confirmed that NOD-2 protein was located in cytoplasm. Moreover, 0. 1 mg/L MDP augmented DSP protein level. DSPP and OCN mRNA were elevated with time and reached the peak at 12 h and down-regulated. OPN protein level also increased with time. Conclusions Dental pulp NOD-2 expression are up-regulated in pulp tissue of deep caries. MDP may be related to the differentiation of hDPC.

关 键 词：Nod2信号接头蛋白质 乙酰胞壁酰-丙氨酸-异谷酰胺 细胞分化 牙髓细胞 

分 类 号：R781[医药卫生—口腔医学]