环孢素A对小鼠牙龈上皮细胞凋亡的影响

目的探讨环孢素A(CsA)导致牙龈上皮增厚的机制。方法选取美国癌症研究所(ICR)雄性小鼠,随机均分为实验(T)组和对照(C)组。T组胃饲30 mg/(kg.d)的CsA橄榄油溶液,C组仅给橄榄油。给药1、2、4、6周后处死小鼠,取下颌前牙牙龈及腭中部黏膜组织标本,制备切片。用末端转移酶介导的三磷酸脱氧尿苷缺口末端标记实验(TUNEL)检测牙龈上皮的口腔龈上皮、龈缘-沟内上皮和腭黏膜上皮细胞凋亡率。结果T组1、2周时,龈缘-沟内上皮细胞凋亡率显著降低,且TUNEL阳性细胞主要分布于上皮表层,棘层和基底层少见,而C组阳性细胞则可见于牙龈上皮各层;4、6周时两凋亡率无明显变化。各观察时间,小鼠口腔龈上皮细胞和腭黏膜上皮细胞凋亡率改变无统计学差异。结论CsA早期对小鼠牙龈上皮细胞调亡有明显抑制作用,提示其诱导小鼠牙龈上皮增生早期可能与牙龈上皮细胞的凋亡抑制有关。     

环孢素对大鼠牙龈上皮细胞凋亡及Bcl-2、Caspase-3蛋白表达的影响

目的 观察环孢素(CsP)对大鼠牙龈上皮细胞凋亡活动、凋亡相关蛋白Bcl-2和Caspase-3表达的影响,探讨CsP致牙龈上皮增厚的可能机制.方法 SPF级7周龄雄性Wistar大鼠80只,随机分为实验组和对照组,每组又分为10、20、30、40 d亚组,实验组胃饲含CsP鲜牛奶,对照组胃饲等量鲜牛奶.经心灌注4%多...     

环孢素诱导牙龈上皮细胞增生的机制

药物性牙龈增生(DGO)是由于服用免疫抑制剂、钙通道阻滞剂、抗癫痫药物等而引发的牙龈病变.传统意义上将DGO定义为服用某些药物引起的牙龈纤维增生和体积增大.近来发现,牙龈上皮细胞增厚也是引起DGO的重要原因之一.下文就环孢素抑制牙龈上皮程序性细胞死亡和促进牙龈上皮细胞增殖等机制作一.     

吸烟对牙龈上皮细胞凋亡的影响

目的:观察不同程度吸烟患者的牙龈上皮棘层和基底层细胞凋亡的情况,评价吸烟对牙龈上皮细胞正常代谢和蛋白质分泌的影响。方法:选取47例具有不同吸烟史、无严重系统疾病且行牙冠延长术或智牙拔除术的患者为研究对象,男41例,女6例,年龄18～29岁(平均年龄21.4岁),根据吸烟史、日平均吸烟支数和总吸烟支数,将患者分为Ⅰ(轻)度(吸烟史<5a,或2≤日均支数<10且总支数约1.5万支以下)19例,Ⅱ(重)度(5a≤吸烟史,或10≤日均支数且总支数约1.5万支以上)28例。另取无吸烟史的10例患者作为对照组。采用原位末端标记(TdT-mediated-dUTPnickendlabeling,TUNEL)法检测牙龈上皮棘层和基底层细胞的凋亡情况。采用Newman-Keuls法比较各吸烟组之间及其与对照组间的差异,取α=0.05水准。结果:吸烟者的牙龈上皮棘层和基底层细胞凋亡阳性的表达高于未吸烟者,且棘层(P<0.01)改变较基底层(P<0.05)明显。轻度吸烟组和重度吸烟组之间也存在显著性差异(P<0.05、P<0.01)。结论:吸烟对牙龈上皮棘层的凋亡具有明显的促进作用,从而干预上皮细胞的正常蛋白分泌和代谢。     

牙龈卟啉单胞菌影响血管内皮细胞增殖和凋亡的实验研究

目的 观察牙龈卟啉单胞菌(Porphyromonas gingivatis,Pg)对血管内皮细胞增殖和凋亡的影响,探讨Pg在动脉粥样硬化发病机制中的作用.方法 建立体外Pg侵入血管内皮细胞模型,甲基噻唑基四唑(MTT)法观察细胞增殖,碘化丙啶染色、流式细胞仪分析细胞周期,Annexin-V-FITC凋亡试剂盒检测细胞凋亡.结果 PgATCC33277侵入后72 h细胞增殖活性降低12.46%,Pg W83侵入后72 h细胞增殖活性降低10.47%(F=786.68,P<0.01);Pg W83侵入后24 h使G1期细胞增加(F=43.23,P<0.01),ATCC 33277侵入后48 h使G1期细胞增加(F=66.72,P<0.01);Pg侵入后24 h即诱导细胞凋亡(F=1074.56,P<0.01).结论 Pg可能通过细胞毒性及诱导凋亡作用,加重血管内皮细胞的局部炎性反应,在动脉粥样硬化炎性病理反应中有重要意义.     

硝苯地平对体外培养的人牙龈上皮细胞增殖和凋亡的影响

目的：通过观察硝苯地平（NIF）对牙龈上皮细胞增殖和凋亡的影响，探讨硝苯地平致龈增生的机理。方法：采用MTT法检测不同浓度NIF对体外培养的人牙龈上皮细胞增殖的影响；采用流式细胞仪（R、M）检测上皮细胞受NIF诱导后凋亡小体形成百分率。结果：24h、48h、72h后各加药组与对照组之间MTT值没有明显差异；48h后高浓度药物（1200μg／1）凋亡小体形成率小于对照组（P〈0．05），且主要作用于细胞G0／C1期和S期。绪论：硝苯地平对体外培养的人牙龈上皮细胞的增殖没有直接刺激作用，但高浓度的NIF可抑制细胞凋亡。     

环孢素对大鼠牙龈上皮细胞凋亡及Bcl-2、Caspase-3蛋白表达的影响

SPF级7周龄雄性Wistar大鼠80只,随机分为实验组和对照组,每组又分为10、20、30、40d亚组,实验组胃饲含CsP鲜牛奶,对照组胃饲等量鲜牛奶。经心灌注4%多聚甲醛,固定取材,制作下颌第一磨牙颊舌向石蜡切片,原位缺口末端标记(TUNEL)法检测牙龈上皮细胞原位凋亡,免疫组化PV两步法检测Bcl-2和Caspase-3蛋白的表达。利用图像分析系统计算牙龈上皮细胞凋亡率和Caspase-3蛋白阳性细胞表达率,并测量Bcl-2蛋白平均灰度,行完全随机分组两因素析因设计方差分析。     

环孢素对大鼠牙龈组织形态影响的定量分析

目的定量分析环孢素（CsP）对大鼠牙龈组织形态影响的部位特异性和时间依赖性。方法将80只7周龄雄性Wistar大鼠随机分为实验组和对照组,每组又分为10、20、30、40 d亚组。实验组胃饲含CsP的鲜牛奶,对照组胃饲等量鲜牛奶。内固定取材后制作下颌第一磨牙颊舌向石蜡切片,HE染色,利用图像分析系统分别测量颊侧和舌侧牙龈上皮面积、结缔组织面积、最长钉突长度,行完全随机分组两因素析因设计资料的方差分析。结果实验组大鼠牙龈增厚,颊侧附着龈近膜龈联合处上皮钉突明显增生伸长。实验组大鼠颊侧和舌侧牙龈上皮面积和结缔组织面积以及颊侧最长钉突长度均显著大于对照组（颊侧P＜0.01,舌侧0.01＜P＜0.05）,2组间舌侧最长钉突长度差异无统计学意义。各时间点相比,颊侧和舌侧上皮面积、结缔组织面积以及最长钉突长度间差异无统计学意义。结论CsP对大鼠颊侧膜龈联合端附着龈上皮的影响存在部位特异性,对大鼠牙龈的影响无时间依赖性。     

牙龈卟啉单胞菌脂多糖对泡沫细胞凋亡基因的影响

目的 了解牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)脂多糖(lipopolysaccharide,LPS)在巨噬细胞吞噬氧化低密度脂蛋白(oxidized low density lipopmtein,oxLDL)形成泡沫细胞过程中和形成后对凋亡基因的影响,以期了解Pg影响动脉粥样硬化的可能机制.方法 以oxLDL、oxLDL+Pg-LPS刺激人急性单核细胞白血病单核细胞株THP-1源性巨噬细胞,以及oxLDL诱导巨噬细胞形成的泡沫细胞.采用吖啶橙-溴化乙锭双染色观察细胞凋亡,聚合酶链反应(PCR)芯片检测11种动脉粥样硬化相关凋亡基因的变化,实时PCR检测p53、c-Myc和半胱氨酸天冬氨酸蛋白酶(caspase)-3基因的变化.结果 Pg-LPS提高了巨噬细胞吞噬oxLDL形成泡沫细胞过程中和形成后的细胞凋亡率,分别为(5.47±0.93)%、(7.50 4-0.54)%;PCR芯片检测显示泡沫细胞形成过程中Pg-LPS上调了B细胞淋巴瘤-白血病-2相关蛋白Al的转录(>2倍),泡沫细胞形成后上调了B细胞淋巴瘤-白血病-2和B细胞淋巴瘤-白血病-2相关蛋白A1的转录(>2倍);在泡沫细胞形成过程中提高了p53和caspase-3的转录水平[分别为(4.50×10-3±4.02×10-4)和(5.30×10-2±4.58×10-3)],抑制了c-Myc的转录水平(1.53×10-2±5.77×10-4);在泡沫细胞形成后降低了p53转录水平(4.23×10-3±5.85×10-4),促进了caspase-3的转录水平(6.00×10-2±6.08×10-3),P<0.05.结论 Pg-LPS影响了泡沫细胞形成过程中和形成后细胞中多种凋亡基因的转录,促进了凋亡的发生.     

菌斑在环孢素A导致牙龈过度生长中的作用

目的：探讨菌斑在环孢素A导致牙龈过度生长中的作用。方法：20只SD大鼠,拔除单侧下颌磨牙后随机分为实验组（环孢素A,10mg/k&#183;d皮下注射）和对照组（等量生理盐水皮下注射）,4周后切取下颌牙龈,体视显微镜下测量牙龈宽度。牙龈组织切片后镜检,并以Image Pro-plus 6.0图像分析软件对上皮和结缔组织进行线性测量。以SAS6.12软件包进行数据分析。结果：实验组用药后4周有（无）牙侧牙龈宽度均显著高于对照组（P〈0.05）。结论：菌斑虽非环孢素A导致牙龈病理性过度生长的始动因素,但对牙龈病理性生长有一定促进作用。     

Cyclosporin A inhibits production and activity of matrix metalloproteinases by gingival fibroblasts

Cyclosporin A (CyA) is a potent immunosuppressor used in organ transplantation and in the management of various autoimmune diseases. Gingival overgrowth is one of the side-effects of the CyA-treatment, affecting the attached gingiva of 25-81% of treated patients. To investigate the production and activity of matrix metalloproteinases (MMPs) in the CyA-induced gingival overgrowth, 2 well-documented models were utilized: the in vivo CyA-induced rat gingival overgrowth and primary cultures of human gingival fibroblasts treated with CyA. Our results obtained from the Western blot assays demonstrated clearly that the production of MMP-1 and MMP-3 was significantly inhibited by CyA at similar concentrations found in the serum of patients undergoing CyA-treatment. Moreover, the gelatinolytic activity of MMP-2 was also reduced both in cultured fibroblasts and in the rat CyA-induced gingival overgrowth. Taken together, the data presented here suggest that these inhibitory effects may contribute to the extracellular matrix (ECM) components accumulation in the CyA-induced gingival overgrowth.     

药物性牙龈增生发病机制的研究进展

药物性牙龈增生是指服用抗癫痫药、钙通道阻滞剂和免疫抑制剂等某些特定药物引起的牙龈增生和体积增大,具有共同的病理组织学特点,其发病机制目前仍无定论。下面就药物性牙龈增生在胶原的合成与降解失衡、上皮细胞的增殖和程序性细胞死亡以及上皮下炎症浸润机制上取得的研究进展作一综述。     

Cyclosporin associated gingival overgrowth in renal transplant recipients

OBJECTIVES: To investigate the prevalence and severity of gingival overgrowth in a group of renal transplant recipients treated in one centre in Northern Ireland. STUDY DESIGN: A consecutive group of patients who had had a renal transplant for at least 6 months and were attending the Renal Unit in Belfast City Hospital took part in the study. These were divided into a group of 84 subjects treated with cyclosporin since their transplant who were compared with a control group of 36 transplant recipients who had never received cyclosporin. Each subject had a periodontal examination and completed a questionnaire. The severity of gingival overgrowth was scored from plaster models. OUTCOME MEASURES: Clinically significant gingival overgrowth was equated with a score of > or = 30 using the index developed by Seymour et al (1985). RESULTS: 41 (49%) of the cyclosporin group had clinically significant gingival overgrowth compared with none of the controls. A significantly higher proportion of males had overgrowth than females. There were significant correlations between age at transplant, plaque, bleeding, pocketing and the severity of gingival overgrowth. Many patients with clinically significant gingival overgrowth were apparently unconcerned about this condition. CONCLUSIONS: It is concluded that gingival overgrowth is a significant problem for renal transplant patients treated with cyclosporin, particularly if they are also treated with a calcium channel blocker. None of the factors measured, in isolation, explained the variable expression of gingival overgrowth in those at risk.     

环孢素A诱导牙龈增生动物模型的建立及其病理学表现

目的:建立环孢素A(CyclosporinACsA)诱导的牙龈增生小鼠动物模型,观察其病理学表现,并进行组织测量,确定其可靠性。方法:将CsA溶于橄榄油中,按 30mgCsA/kg体重 /d胃饲远交群ICR雄性小鼠,分别在给药 2、4、6、8周时,随机取实验组小鼠下颌前部标本,体视显微镜下测量其下颌前牙龈体积;制作切片,光镜下观察其牙龈病理表现,并利用图象分析系统测量舌侧牙龈缘上皮厚度。结果:小鼠经胃饲 30mg/kg体重 /d的CsA,①4周后,肉眼见部分下颌前牙舌侧牙龈球形肥大;②体视显微镜下牙龈体积测量显示下颌前牙舌侧牙龈 4周至 8周明显增大(P<0. 01);③此时光镜下开始出现明显的牙龈增生病理表现:上皮增厚,上皮钉突明显且变宽,牙龈结缔组织增厚,基质和成纤维细胞增生,血管扩张等。④龈缘上皮厚度测量 2周时上皮增厚(P<0. 01), 4周增厚更明显(P<0. 001),持续至 8周。结论:胃饲小鼠CsA可诱导牙龈增生,其病理表现与其他动物模型和临床病理一致,该模型有一定可靠性,可用于进一步研究CsA诱导的牙龈增生的发病机理。     

药物性牙龈肥大发病机制的研究进展

药物性牙龈肥大(DIGO)主要由长期服用苯妥英钠、环孢素A、硝苯地平引起,不仅影响牙面的清洁与美观和牙齿正常生理功能,而且可能造成患者心理上的障碍。然而,DIGO发病机制复杂,无法明确,导致治疗较为棘手。许多学者对其进行了多方面的研究,提出许多观点与假设,包括胶原生成与降解失衡机制、炎症等。该文从分子机制与药物具体机制两方面总结了近几年对DIGO发病的研究,并对DIGO未来的研究方向进行探讨,希望能够对DIGO的预防与临床治疗有所帮助。     

Morphological evaluation of combined effects of cyclosporin and nifedipine on gingival overgrowth in rats

It has previously been shown that, while cyclosporin A (CsA) and nifedipine both cause gingival overgrowth in the rat, the combined use of these drugs increases the severity of overgrowth. The aim of this study was to describe the histometry and densities of fibroblasts, collagen fibers and vessels in the gingival tissue of rats that were treated with CsA and nifedipine, either alone or in combination. Rats were treated for 60 days with a daily subcutaneous injection of 10 mg/kg body weight of CsA and/or with 50 mg/kg body weight of nifedipine added to the chow. The results confirmed that CsA causes a more severe overgrowth than nifedipine, and that the combined use of these drugs increases the overgrowth severity. All the rat groups that were studied showed that, as the severity of overgrowth increased, there was a parallel increase in fibroblasts and collagen, and a decrease in vessel content. Therefore, independently of whether the gingival overgrowth was caused by CsA alone, nifedipine alone, or both treatments in combination, the fibroblast and collagen density increased in parallel with the severity of the overgrowth.     

Reduction in gingival overgrowth associated with conversion from cyclosporin A to tacrolimus

BACKGROUND: Unsightly gingival overgrowth affects many individuals immunosuppressed with cyclosporin A (CsA). Current management involves repeated periodontal surgery and intensive hygienist support. Tacrolimus is an effective alternative immunosuppressive agent for renal transplantation which does not appear to produce gingival enlargement. AIMS: The purpose of the present study was to monitor the gingival response of 4 renal transplant patients (RTPs), with clinically significant CsA-induced gingival overgrowth, after their immunosuppressive therapy was switched to tacrolimus. METHODS: Intra-oral photographs and alginate impressions were taken both prior to the drug conversion and again, 6 to 9 months later. Gingival overgrowth scores were determined, from plaster models on both these occasions. RESULTS: All of the RTPs experienced significant resolution of their gingival enlargement within the time period studied; however, only one had complete regression. CONCLUSION: It is concluded that conversion of RTPs with gingival overgrowth from CsA to tacrolimus may provide an effective management strategy for this clinical problem.