Immunohistochemical localization of inducible nitric oxide synthase in synovial tissue of human temporomandibular joints with internal derangement

The expression and distribution of inducible nitric oxide synthase (iNOS) was examined in 12 samples of human temporomandibular joint (TMJ) with internal derangement (ID) and four control specimens. In the diseased joints, strong or definite iNOS reactivity was expressed in synovial lining and endothelial cells; weaker activity was present in synovial fibroblasts. In contrast, although there was weak expression of iNOS in synovial fibroblasts and endothelial cells in the two control specimens, there was no iNOS staining in the synovial lining cell layers. This original report that iNOS is expressed in the synovial tissue of the temporomandibular joint indicates that nitric oxide is produced locally at least in the synovial lining in these joints when affected by internal derangement.     

A study to assess inducible nitric oxide synthase expression in oral lichen planus

Nitric oxide (NO) has been implicated in a variety of diseases but has not been previously studied in oral lichen planus (OLP). Since OLP has a complex immunogenesis with abundant macrophage infiltration, this study determined by immunohistochemistry whether or not the expression of the inducible form of nitric oxide synthase (iNOS) was increased in this condition relative to normal mucosa. Thirty cases of OLP and 10 normal buccal mucosa biopsies were studied utilising primary antibodies to iNOS and CD68, a myelomonocytic marker. iNOS activity was additionally assessed using a [(14-)C]-labelled arginine to citrulline assay. CD68 expression was significantly increased in the cellular infiltrate of all 30 cases of OLP compared with normal mucosa (P<0.009). Although iNOS staining was seen in a minority of cells in nine cases, this was not statistically significant when compared with the absent staining in normal oral mucosa (P=0.26). Furthermore, the minimal iNOS activity found in OLP was similar to that in normal mucosa. We conclude that expression of iNOS by macrophages is downregulated in OLP and discuss the possible reasons for this finding.     

Measurement of nitric oxide in temporomandibular joint saline aspirates

Temporomandibular joint (TMJ) saline aspirates, obtained from the upper joint space of 17 patients undergoing TMJ arthroscopy under general anaesthesia were assayed for the presence of nitrite, a stable metabolite of nitric oxide by a spectrophotographic method using the Griess reaction. Measurable levels of nitrites were found in the saline aspirates of both symptomatic and asymptomatic joints. There was no statistically significant difference between the two sides. The presence of nitric oxide metabolites in the asymptomatic joints has not been previously reported in the literature. This finding may represent a latent disease process in the symptomless joint.     

口腔癌中诱导型一氧化氮合酶与血管内皮生长因子表达关系的研究

目的研究诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)在口腔癌中表达水平以及与口腔癌血管内皮生长因子(vascular endothelial growth factor,VEGF)表达和淋巴结转移的关系.方法以正常口腔粘膜作对照,采用免疫组化SP法检测41例口腔癌组织中iNOS的表达,同时检测口腔癌中VEGF的表达和微血管密度(MVD)(CD34标记).结果口腔癌组织iNOS阳性表达率为63.41%,淋巴结阴性组和阳性组差异有显著性(P<0.01),而9例正常口腔粘膜表达均为阴性;在iNOS不同表达组间MVD值差异有高度显著性(P<0.001),VEGF的表达差异有显著性(P<0.05).结论 iNOS在口腔癌中高表达,并与肿瘤血管形成、淋巴结转移密切相关;它可能参与VEGF促血管生成作用.     

MicroRNA-203 up-regulates nitric oxide expression in temporomandibular joint chondrocytes via targeting TRPV4

ObjectiveMicroRNAs (miRNAs) are recognised as important regulators of a variety of fundamental biologic processes. Our study was undertaken to examine the role of MicroRNA-203 (miR-203) in modulating nitric oxide (NO) expression in female Sprague–Dawley rat mandibular condylar chondrocytes (MCCs) via targeting transient receptor potential vanilloid 4 (TRPV4) and to demonstrate the possible mechanism of NO inhibition by chondroprotective factor 17β-oestradiol (E2).MethodsThe expression of TRPV4 in mandibular condylar cartilage tissue and MCCs was detected by immunohistochemistry, immunofluorescence (IF), RT-PCR and Western blot, respectively. Primary SD rat MCCs were exposed to lipopolysaccharide (LPS), plus Ruthenium Red, 4α-phorbol 12,13-didecanoate (4αPDD), over-expressed miR-203 or E2 (10^?9 to 10^?6 M), the cellular supernatants were used for NO assay, miR-203 levels were measured by quantitative RT-PCR while TRPV4 expression changes were analysed by Western blot. The dual luciferase activity assay was performed to identify the target gene of miR-203.ResultsTRPV4 and miR-203 were stably expressed in MCCs. The MCCs’ expression of NO evoked by LPS could be enhanced or depressed by Ruthenium Red or 4αPDD. The dual luciferase assay suggested that TRPV4 was the direct target gene of miR-203. Over-expression of miR-203 inhibited the expression of TRPV4 and increased NO expression in MCCs. E2 inhibited NO expression by inhibition of miR-203, which was concurrent with the up-regulation of TRPV4 expression level in MCCs.ConclusionOur findings first suggested that miR-203 could up-regulate NO expression in female rat MCCs via targeting TRPV4. Moreover, the inhibition of NO by E2 might be at least in part through this mechanism.     

Effect of cyclosporin A on the expression of inducible nitric oxide synthase in the gingiva of rats

BACKGROUND: The role of nitric oxide (NO) in the pathogenesis of cyclosporin A (CsA)-induced gingival overgrowth is still unknown. The purpose of this study was to evaluate the effect of CsA on the expression of nitric oxide synthases (NOS) in the gingival tissue of rats. METHODS: Thirty male Sprague-Dawley rats were randomly assigned to a control and two test groups. Rats in each group received CsA (0, 10, or 30 mg/kg) daily by gastric feeding for 4 weeks. The plasma NO and the NOS enzyme activities were assayed at week 4 in the blood samples and in the gingiva and lung tissue specimens, respectively. The distribution of inducible nitric oxide synthase (iNOS) was further evaluated in tissues obtained from the gingiva and lung at the end of weeks 1 and 4 by immunohistochemistry. RESULTS: In the CsA-treated animals, increased levels of plasma nitrites/nitrates were measured in comparison to those in control rats. Significantly greater iNOS enzyme activities were detected in lung and gingival tissues obtained from CsA-treated animals than from control animals. In addition, cells positively staining for iNOS were clearly observed in both gingival and lung tissues obtained from the CsA-treated animals by immunohistochemistry, whereas a few stained cells were found in those from the control group. The quantity of cells positively stained for iNOS was greater in tissue from week 4 than week 1. CONCLUSIONS: The effect of CsA on gingival iNOS expression was evaluated in rats for 4 weeks. A greater iNOS expression in the gingiva was observed after CsA therapy by both enzyme activities and immunohistochemica staining. Therefore, we suggest that CsA can increase gingival iNOS expression, which may play an important role in cyclosporin-induced gingival overgrowth.     

大鼠实验性牙髓炎组织中诱导型一氧化氮合成酶的mRNA表达

目的：探讨诱导型一氧化氮合成酶（ｉｎｄｕｃｉｂｌｅｎｉｔｒｉｃｏｘｉｄｅｓｙｎｔｈａｓｅ，ｉＮＯＳ）在牙髓炎症中的ｍＲＮＡ表达。方法：建立大鼠牙髓炎模型，并随机分为４组：正常对照组，牙髓炎２４ｈ、７２ｈ和１２０ｈ组。采用反转录－聚合酶链式反应（ｔｈｅｒｅｖｅｒｓｅｔｒａｎｓｃｒｉｐｔａｓｅ－ｐｏｌｙｍｅｒａｓｅｃｈａｉｎｒｅａｃｔｉｎ，ＲＴ－ＰＣＲ）方法，测定各组ｉＮＯＳｍＲＮＡ表达量。结果：大鼠牙髓炎早期，局部病灶可见大量中性粒细胞浸润，ｉＮＯＳ表达以各炎症组较对照组升高，其中炎症７２ｈ组明显增高。结论：牙髓炎早期，中性粒细胞可能是ｉＮＯＳ分泌的主要部位，并且ｉＮＯＳ的产生与炎症病程有关，表明它在早期牙髓炎的发生发展中起作用     

Inducible nitric oxide synthase expression in periodontitis

Recently, nitric oxide (NO) has been shown to be vital in inflammatory processes. Nitric oxide synthase (NOS) exists in three different isoforms, two constitutively produced with physiological roles, and an inducible form, iNOS, which is involved in inflammation. This study examined the localisation of iNOS in biopsies from patients with periodontitis using immunohistochemistry, and compared these with healthy tissue biopsies. Biopsies were obtained from 16 periodontitis patients undergoing periodontal surgery and from clinically healthy tissues of 5 patients having crown lengthening procedures. The periodontitis diseased tissue demonstrated a greater level of iNOS expression than the healthy tissue. The source of iNOS in the periodontal tissues was determined by our monoclonal antibody to be the macrophage, with the endothelial cells also contributing. A role for NO in the inflammatory response of periodontal tissues is suggested, but the precise role requires further elucidation.     

诱导型一氧化氮合酶表达在口腔癌前病变口腔鳞癌发展过程中的作用研究

目的　探讨诱导型一氧化氮合酶 (iNOS)在口腔癌前病变、口腔鳞癌发展过程中的表达情况及其作用。方法　采用免疫组化SABC法检测 10例正常口腔黏膜、8例上皮单纯增生、2 0例上皮异常增生和 3 2例鳞状细胞癌组织中iNOS的表达。结果　正常口腔黏膜iNOS阴性表达 ;上皮异常增生组和鳞癌组中iNOS的表达较上皮单纯增生组均显著增加 (P <0 .0 5 ) ;随着上皮异常增生程度的加重 ,iNOS的标记指数逐级显著上升 (P <0 .0 5 ) ;上皮异常增生组与鳞癌组之间以及鳞癌的各病理分级之间iNOS的表达均无显著性差异 (P >0 .0 5 )。结论　iNOS的表达可能参与了口腔鳞癌的衍进过程     

诱导型一氧化氮合酶基因转染兔牙周膜细胞的瞬时表达检测

目的检测含有人诱导型一氧化氮合酶（iNOS）基因的重组质粒pEGFP-iNOS体外转染兔牙周膜细胞后的瞬时表达情况,为动物牙周局部导入外源性iNOS基因奠定实验基础。方法通过脂质体介导将重组真核质粒pEGFPiNOS转染兔牙周膜细胞,在荧光显微镜下观察瞬时转染情况。并在转染后12 h与48 h,应用实时定量PCR检测iNOS基因的转录,Western免疫印迹技术检测iNOS蛋白表达。设空质粒转染组和空白组为对照。结果重组质粒转染后12 h即可观察到荧光蛋白的表达,pEGFP-iNOS转染组细胞中有iNOS mRNA转录及iNOS蛋白的表达。结论iNOS基因成功导入兔牙周膜细胞,瞬时转染后可在基因和蛋白水平检测到外源性基因的表达。在兔牙周组织导入iNOS基因从而诱导NO生成是具有可行性的。     

Expression and pathological relevance of inducible nitric oxide synthase in osteosarcoma of the jaws

The aim of the present study was to examine the expression of inducible nitric oxide synthase (iNOS) in osteosarcoma of the jaw, and its relationship with tumour angiogenesis and clinicopathological characteristics. Streptavidin peroxidase immunohistochemical staining was used to detect the expression level of iNOS and CD34 in paraffin-embedded samples from 25 patients. Osteosarcoma of the jaw was associated with overexpression of iNOS, which correlated with tumour microvessel density (MVD). iNOS expression correlated with the size, pathological grade and clinical stage of the osteosarcoma, and also with clinicopathological characteristics such as primary occurrence or recurrence of tumours. There was no correlation with metastasis. iNOS may promote tumour angiogenesis in osteosarcoma of the jaw, and so may represent an important target in anti-tumour therapy.     

诱导型一氧化氮合酶在颌骨肉瘤中的表达及意义

目的：研究诱导型一氧化氮合酶（iNOS）在颁骨肉瘤中的表达情况及其和肿瘤血管形成、临床病理特征之间的关系。方法：应用S-P免疫组织化学法检测iNOS和CDB4在颌骨肉瘤中的表达。结果：颌骨肉瘤中存在iNOS的过度表达;iNOS表达与微血管密度有关;iNOS表达与颌骨肉瘤大小、病理分级、临床分期、初／复发等临床病理特征有关,与肿瘤的转移无关。结论：iNOS有促进颌骨肉瘤中肿瘤血管形成的作用,iNOS是肿瘤治疗的一个重要靶点。     

Expression of inducible nitric oxide synthase and p53 in oral epithelial dysplasia

AIM: Nitric oxide (NO) has been studied in a variety of human cancers and is implicated in both tumor promotion and inhibition. Downregulation of the enzyme iNOS by wild-type p53 (but not mutant) protein has been shown to occur in normal cells and some tumors, but the relationship has not been reported in oral epithelial dysplasia. METHODS AND RESULTS: An immunohistochemical study was conducted with antibodies to iNOS and p53 (clone DO-7) in 36 cases of oral dysplasia of varying severity. Statistical analysis showed a significant correlation between iNOS staining and grade of dysplasia (P <.001) and between p53 and iNOS staining (P <.001). CONCLUSIONS: This preliminary study has shown that iNOS expression correlates with severity of dysplasia, and it is also increased in those cases showing positive staining for p53. Further research is required to fully establish the relationship between iNOS and p53 in both dysplasia and oral squamous cell carcinoma.     

大鼠正畸牙移动中牙髓iNOS表达的免疫组化研究

目的:建立大鼠正畸牙移动模型,观察牙髓组织中诱导型一氧化氮合酶(iNOS)的表达及分布,探讨正畸牙移动过程中牙髓改建的分子机制。方法:采用免疫组织化学方法对正畸加力后12h、1d、3d、7d和14d大鼠牙髓组织中iNOS进行检测,观察iNOS的时空分布。结果:iNOS阳性反应的产物呈深褐色均质沉淀,主要在血管内皮细胞、成牙本质细胞胞浆核周区颗粒状阳性表达。这种染色在正畸加力后12h、1d、3d天有不同程度的增强,3d达到高峰,加力后7d和14d表达减弱,第14d与对照组无明显差异。结论:正畸牙移动过程中牙髓组织iNOS的表达先升高后逐渐恢复正常,提示iNOS可能在正畸牙移动牙髓组织改建过程中起重要作用。