牙龈卟啉单胞菌促进人脐静脉内皮细胞一氧化氮的生成

目的:观察牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)对人脐静脉内皮细胞(human umbilical vein endothelialcells,HUVEC)一氧化氮(NO)生成的影响,探讨Pg对内皮细胞功能损伤的途径,以期为牙周病在动脉粥样硬化发病机制中的作用提供依据.方法:用感染复数(multiplicity of infection,MOI)1∶10、1∶100Pg干预HUVEC,未受Pg干预的HUVEC作为阴性对照组,分别于4、8、12、24 h时收集细胞上清液,利用硝酸还原酶法测定细胞上清液中NO的浓度:Western.blot检测诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)蛋白表达水平;透射电镜观察Pg对HUVEC的黏附和入侵方式.结果:在24 h内,PgMOI 1∶10、1∶100能促进HUVEC NO的生成,与阴性对照组相比差异有统计学意义(P<0.05),PgMOII∶10,MOII∶100可以诱导HUVEC iNOS的蛋白表达,抑制eNOS的蛋白表达,与阴性对照组相比差异均有统计学意义(P<0.05),透射电镜观察Pg能够利用其菌毛黏附于HUVEC细胞表面并入侵到HUVEC细胞胞质内,定植于细胞内.结论:Pg能够黏附于HUVEC并入侵到细胞胞质内,诱导iNOS蛋白表达,抑制eNOS的蛋白表达,最终促进HUVEC NO的生成.过量的NO可能发挥细胞毒性作用,导致内皮功能失调.

Porphyromonas gingivalis stimulate release of nitric oxidein cultured human umbilical vein endothelial cells

Objective:To observe the effect of Porphyromonas gingivalis (Pg) on the production of nitric oxide (NO) in cultured human umbilical vein endothelial cells(HUVEC), and investigate the pathway of Pg in damaging in endothelial function. Methods: HUVEC were treated with PgATCC33277 at multiplicity of nfection (MOI)1:10,1:100 for 4,8,12,24 h respectively, nitric oxide production was assayed by measuring the accumulation of nitrite in culture supernatants; western-blot analysis of inducible nitric oxide synthase ...