实验性糖尿病牙周炎诱导成骨细胞凋亡的研究

目的观察糖尿病牙周炎条件下成骨细胞的凋亡情况。方法选用SD大鼠62只,随机分为糖尿病牙周炎组（DP）、单纯牙周炎组（P）以及空白对照组（N）。采用一次性腹腔注射链脲佐菌素（STZ）的方法诱导大鼠糖尿病模型,采用丝线结扎联合口内接种细菌的方法建立牙周炎模型。各组动物分别于DP组、P组丝线结扎后第3、6周时分批处死,取标本进行组织学检测,并计算各组成骨细胞凋亡百分率。结果丝线结扎后3、6周时,成骨细胞凋亡百分率由高至低依次为DP组、P组、N组,组间两两比较均有统计学意义（P＜0.05）。在丝线结扎后3周和6周时,DP组成骨细胞凋亡百分率均达到P组的2倍。结论糖尿病可促进牙周炎条件下牙周组织中成骨细胞的凋亡。     

实验性糖尿病牙周炎牙周膜中成纤维细胞凋亡的初步研究

目的:初步探讨糖尿病牙周炎条件下牙周膜中成纤维细胞的凋亡情况. 方法:选用 6 周雄性SD大鼠62 只,随机分为糖尿病牙周炎组(DP)、牙周炎组(P)和正常对照组(N).采用一次性腹腔注射STZ的方法诱导大鼠糖尿病模型,采用丝线结扎联合口内接种细菌的方法建立牙周炎模型.动物分别于丝线结扎后3 周和6 周分批处死,进行HE染色和原位细胞凋亡检测.观察指标包括:组织病理学比较,牙周膜中成纤维细胞计数,牙周膜中成纤维细胞凋亡百分率.资料采用单因素方差分析统计学处理.结果:丝线结扎后3 周和6 周,与N组比较,P组和DP组单位面积牙周膜中成纤维细胞数减少,与P组比较,DP组单位面积牙周膜中成纤维细胞数亦显著减少(P<0.05).牙周膜中成纤维细胞凋亡百分率DP组＞P组＞N组,组间两两比较均有统计学意义(P<0.05).在丝线结扎后3 周和6 周,DP组牙周膜中成纤维细胞凋亡百分率均达到P组的2 倍左右.结论:糖尿病可加强牙周炎条件下牙周膜中成纤维细胞的凋亡,降低这些细胞的数量.     

破骨细胞与糖尿病相关慢性牙周炎关系的研究进展

糖尿病是慢性牙周炎（chronic periodontitis,CP）发生的危险因素,糖尿病患者长期高血糖会使机体产生大量高级糖基化终产物（advanced glycosylation end products,AGEs）,通过氧化应激、细胞信号传导等途径将机体固有免疫系统激活,进而增强牙周组织的炎症反应,导致糖尿病相关性CP发生。破骨细胞（osteoclasts,OC）主要参与骨改建及骨吸收过程,对于维持人体骨组织稳态具有重要作用。OC与CP患者牙槽骨吸收密切相关,但与糖尿病相关CP的关系尚不明确。本文基于糖尿病相关CP发病机制,从炎症反应、AGEs、活性氧（reactive oxygen species,ROS）三个方面阐述OC与糖尿病相关CP的潜在关系,并做一综述。     

细胞凋亡在糖尿病大鼠牙周炎中参与牙槽骨吸收的实验研究

目的研究糖尿病伴牙周炎牙槽骨破坏机制,初步探讨牙周组织细胞凋亡在该类疾病中所起的作用。方法采用腹腔注射链脲佐菌素（Streptozocin,STZ）制备SD大鼠糖尿病模型,并利用0.2mm不锈钢丝环扎大鼠磨牙颈部制备牙周炎动物模型。观察牙周组织细胞在高血糖状态及正常血糖状态下的组织形态并检测细胞凋亡情况。结果高血糖状态下大鼠牙周炎发病程度明显高于血糖正常大鼠。牙周组织中成骨细胞及牙周膜成纤维细胞凋亡数量高血糖组高于血糖正常组,而破骨细胞数量则相反。结论高血糖状态下牙周炎病损程度较正常血糖状态下严重,牙周组织细胞凋亡参与和加重病程。     

实验性糖尿病牙周炎骨丧失动物模型研究

目的:建立实验性糖尿病牙周炎骨丧失动物模型,以进一步揭示糖尿病加重牙周炎骨丧失的细胞学机制.方法:选用6周龄雄性SD大鼠62只,随机分为糖尿病牙周炎组(DP)、牙周炎组(P)以及正常对照组(N).采用一次性腹腔注射链脲佐菌素(streptozotocin,STZ)的方法诱导大鼠糖尿病模型,采用丝线结扎联合口内接种细菌的方法建立牙周炎模型.动物分别于丝线结扎后3周和6周分批处死,进行HE染色、TRAP染色.观测指标包括:牙槽骨丧失,组织病理学比较,炎症区破骨细胞计数等.资料采用单因素方差分析统计学处理.结果:丝线结扎后3周和6周,大鼠牙槽骨丧失在N组与P组、N组与DP组、P组与DP组不同,组间两两比较均有统计学差异(P＜0.05),牙槽骨丧失DP组＞P组＞N组.炎症区单位长度破骨细胞数在N组、P组、DP组不同,N组与P组比较,N组与DP组比较、P组与DP组比较均有统计学差异(P＜0.05),其炎症区单位长度破骨细胞数DP组＞P组＞N组.结论:糖尿病可加重牙周炎牙周组织破坏,糖尿病条件下牙周炎骨丧失明显增加.糖尿病可能通过促进炎症部位破骨细胞生成,增强骨吸收,促进牙周炎骨丧失.     

糖尿病在大鼠实验性牙周炎发生中的作用

以链脲佐菌素诱发的糖尿病大鼠和健康大鼠为地象，高糖食谱加自身粪便为致牙周病因子，显微镜下观察大鼠磨牙周组织的组织学改变，结果表明正常大鼠在高糖食谱加自身粪便的作用下，９周时方可出现上皮增生，上皮下结缔组织和越隔纤维表层炎细胞浸润，而糖尿病大鼠在同样的实验条件下，３周便出现类似的损害，９周时，出现深层组织的炎细胞浸润。牙槽骨吸收和深牙周袋形成，表明糖尿病具有缩短引起实验性牙周炎的时间和加重牙周组织破     

高压氧对糖尿病型牙周炎牙龈细胞凋亡及凋亡因子表达的调控作用研究

目的 探讨高压氧(hyperbaric oxygen, HBO)对糖尿病型牙周炎（diabetes associated periodontitis, DAP）牙龈组织细胞凋亡及凋亡因子表达的调控作用及机制。方法 选择DAP患者60例,其中20例予以0.25 MPa HBO治疗2周,20例予以牙周洁治和根面平整（scaling and root planning, SRP）治疗,20例予以HBO+SRP治疗,在治疗前和治疗后1个月测定PLI、SBI、GI、PD、AL,用HE染色、TUNNEL染色和透射电镜观察牙龈细胞凋亡,免疫组化（IHC）检测牙龈组织IL 1β、TNF α、PGE2、Caspase3表达。结果 治疗后1个月时HBO组、SRP组、HBO+SRP组SBI、GI、PD比治疗前明显降低;牙龈上皮层和固有层细胞凋亡数量和凋亡细胞阳性表达指数明显降低,牙龈组织IL 1β、TNF α、PGE2及Caspase3表达明显降低。治疗后1个月时HBO+SRP组SBI、GI、PD、AL及牙龈细胞凋亡指数与HBO组和SRP组相比均有显著性差异;牙龈组织IL 1β、TNF α、PGE2、Caspase3表达比HBO组和SRP组降低。IL 1β、TNF α、PGE2主要阳性细胞为巨噬细胞和淋巴细胞,Caspase3 阳性细胞为上皮基底细胞、棘细胞。结论 HBO可显著降低DAP患者牙龈组织中IL 1β、TNF α、PGE2含量,减少牙龈组织中Caspase3表达,抑制细胞凋亡,HBO联合SRP疗效更好,可维持1个月以上。     

糖尿病大鼠实验性牙周炎牙周组织的酶组织化学改变

目的：观察糖尿病和非糖尿病大鼠实验性牙周炎有无本质的不同。方法：以链脲佐菌素诱发的糖尿病大鼠和健康大鼠为实验对象，以高糖食谱加自身粪便为局部致牙周病因子，观察两组牙周组织的酶组织化学改变。结果：两组大鼠均表现有不同程度的酶活性下降，即单纯性牙周炎组表现为较浅层的与糖脂代谢有关的酶活性下降，而糖尿病组则表现为更深层，更广泛的酶活性下降，但从不同种类的酶活性变化看，两组无不同种类的酶活性下降。结论：以酶组化角度表明两组的牙周疾病无差异。     

牙周炎牙槽骨吸收的基础研究—PGE2对破骨细胞性骨吸收的作用

本研究采用分离破骨细胞的体外培养方法,将分离的兔破骨细胞与牛骨片共同培养。相差显微镜观察前列腺素E_2.(Prostaglaodin E_2,PGE_2)对破骨细胞所形成的骨吸收陷窝数及形态学影响。并利用图象分析系统计算吸收陷窝的表面积。结果表明:PGE_2对体外分离的破骨细胞所形成的吸收陷窝数及吸收陷窝面积具有抑制作用。     

Intermittent administration of parathyroid hormone ameliorated alveolar bone loss in experimental periodontitis in streptozotocin-induced diabetic rats

ObjectiveIntermittent administration of parathyroid hormone (PTH) has been demonstrated to have anabolic effects on bone metabolism and is approved for use in the treatment of osteoporosis. This study evaluates the role of intermittent PTH administration on alveolar bone loss in streptozotocin (STZ)-induced diabetic rats.DesignFifty male Sprague Dawley rats were randomly divided into the following five groups: (1) a control group (saline placebo without ligature and STZ injection), (2) a PTH group (PTH administration without ligature and STZ injection), (3) an L group (saline placebo with ligature), (4) an L + STZ group (saline placebo with ligature and STZ injection), and (5) an L + STZ + PTH group (PTH administration with ligature and STZ injection). PTH was administered at 75 μg/kg per dose four times a week for 28 days. Subsequently, all rats were sacrificed, and their mandibles were extracted for micro-computed tomography (micro-CT) scanning, as well as histological and immunochemical evaluation.ResultsMicro-CT scanning demonstrated the anabolic effect of PTH on alveolar bone metabolism in STZ-induced diabetic rats (P < 0.05), and histomorphometry indicated that PTH inhibited inflammation of the periodontium and increased the level of osteoblastic activity (P < 0.05). Immunochemical evaluation showed that rats subjected to both ligature placement and STZ injection had the highest receptor activator of nuclear factor kappa B ligand (RANKL)/osteoprotegerin (OPG) ratio and that PTH administration decreased this ratio.ConclusionIntermittent systemic PTH administration effectively reduced alveolar bone loss and ameliorated the manifestation of experimental periodontitis in STZ-induced diabetic rats.     

Osteocyte death during orthodontic tooth movement in mice

Objective:To investigate the time course of osteocyte death in a mouse model of orthodontic tooth movement (OTM) and its association to the caspase-3 activation pathway and osteoclast formation.Materials and Methods:Twenty-five male wild type CD-1 mice (8–12 weeks old) were loaded with an orthodontic appliance. A spring delivering 10–12 g of force was placed between the right first molar and the incisor to displace the first molar mesially. The contralateral unloaded sides served as the control. The animals were equally divided into five different time points: 6, 12, 24, and 72 hours and 7 days of orthodontic loading. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, caspase-3 immunostaining, and tartrate-resistant acid phosphatase (TRAP) staining was performed on histologic sections of the first molars. The labeling was quantified in osteocytes on the compression side of the alveolar bone at each time point.Results:TUNEL labeling significantly increased at 12, 24, and 72 hours after orthodontic loading; the peak was observed at 24 hours. Elevated caspase-3 labeling was noted at 12, 24, and 72 hours and 7 days after loading, although the increase was not significant. Significant osteoclast formation was initially evident after 72 hours and progressively increased up to 7 days.Conclusions:Osteocyte death during OTM peaks at 24 hours, earlier than initial osteoclast activation. However, only a slight trend for increased caspase-3 activity suggests that other mechanisms might be involved in osteocyte death during OTM.     

Fluid dynamics of gingiva in diabetic and systemically healthy periodontitis patients

OBJECTIVES: The influence of diabetes mellitus (DM) on the fluid dynamics of periodontium has not been reported in periodontal disease. The objectives of this study were (i) to investigate the alterations in the fluid dynamics of periodontium in diabetic periodontitis patients, and present the association of this phenomenon with the metabolic control of DM; (ii) to reveal any correlation between the fluid dynamics of periodontium and clinical signs of periodontal disease in DM and periodontitis. DESIGN: Fifteen well-controlled diabetic chronic periodontitis patients (Group 1), 14 systemically healthy chronic periodontitis patients (Group 2), and 14 systemically and periodontally healthy individuals were included in the study. Gingival crevicular fluid volume (GCF-V) and gingival tissue osmotic pressure (GOP) were used as the parameters of periodontal fluid dynamics. GCF-V was measured by a Periotron device, while GOP was measured by a digital osmometer. Silness-L?e plaque index (PI), L?e-Silness gingival index (GI) and clinical attachment loss (AL) levels were recorded to determine the periodontal health status. RESULTS: PI, GI and AL were higher in Groups 1 and 2 than in Group 3 (P<0.05), but similar between Groups 1 and 2 (P>0.05). Increased GCF-V and GOP were observed in Groups 1 and 2 compared with Group 3 (P<0.01), and the increase in Group 1 was greater than that in Group 2 (P<0.01). There were strong positive correlations between GCF-V and GOP in all three groups: between GI and GCF-V and GI and GOP in Groups 1 and 2; and between AL and GCF-V and AL and GOP in Groups 2 and 3. CONCLUSION: The results suggest that (i) DM may have an additive influence on the fluid dynamics of periodontium in the presence of periodontal disease; (ii) this phenomenon may not be prevented by the metabolic control of DM; (iii) the clinical signs of periodontal disease may be affected by the fluid dynamics of periodontium in both DM and periodontitis.     

氯化镧对大鼠实验性牙周炎的治疗作用

目的:评估镧盐对大鼠实验性牙周炎临床症状以及骨吸收的影响。方法:选健康SD大鼠68只,用外科缝线结扎左侧上颌第二磨牙(M2)颈部并予10%高糖水每日喂养,诱导形成大鼠牙周炎模型。结扎4周后随机选4只大鼠处死,取左侧上颌M2牙周组织块制作切片,观察牙周炎模型建立情况。将造模成功的大鼠随机分成4组,每组16只:生理盐水冲洗对照组(P组);氯己定冲洗组(P1组);镧盐冲洗组(P2组);镧盐喂养组(P3组)。每4周测量各组大鼠临床指标,与治疗前自身对照。治疗3个月后,处死各组大鼠并取左上颌M2牙周组织块制作标本,用体视镜观察并测量牙槽骨吸收情况。结果:治疗后P1、P2、P3组各临床指标较治疗前均有所下降(P<0.05),P组PD、TM虽有下降趋势,但差异无显著性。各组间比较P3组牙槽骨吸收值与面积值较P组显著减少(P<0.05)。结论:0.12%复方氯己定、0.1 mmol/L镧盐水冲洗及0.01 mmol/L镧盐喂养对大鼠牙周炎临床症状的改善效果明显,镧盐喂养对缓解牙槽骨吸收有一定作用。     

Gingival levels of monocyte chemoattractant protein-1 (MCP-1) in diabetes mellitus and periodontitis: an experimental study in rats

The objectives of this study were to investigate and compare the monocyte chemoattractant protein-1 (MCP-1) levels of gingival tissues in diabetes mellitus (DM) and periodontitis and to reveal the effects of MCP-1 on periodontal inflammation and destruction in these diseases. DM was created in 15 rats (group 1) by streptozotocin injection, and periodontitis was obtained by ligature induction in 15 rats (group 2). Fifteen systemically and periodontally healthy rats were used as control (group 3). Gingival MCP-1 levels were measured by enzyme-linked immunosorbent assay (ELISA). Periodontal inflammation was quantified by the inflammatory cell infiltration in the gingival samples, whereas periodontal destruction was assessed by the alveolar bone loss in the experimental regions. MCP-1 concentrations were higher in groups 1 and 2 than in group 3 (p < 0.001). Increased gingival inflammatory cell infiltration and alveolar bone loss were observed in groups 1 and 2 compared to group 3 (p < 0.001). There were positive correlations among the MCP-1 level, gingival inflammatory cell infiltration, and alveolar bone loss in groups 1 and 2 (p < 0.001). Our results suggest that (1) DM may lead to enhanced MCP-1 production in periodontal tissues likewise for periodontitis and (2) there may be a positive correlation between the MCP-1 concentration and diseased nature of periodontium in both diseases.