Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0031099 (periodontitis)
12,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to evaluate neutrophil function in patients suffering from the generalized form of early onset periodontitis (EOP). We investigated neutrophil migration in vivo and neutrophil superoxide production and adhesion in response to a variety of compounds; neutrophils were isolated both from blood and a skin experimental exudate of 15 patients with EOP and of 15 sex- and age-matched normal control subjects. No difference was found in neutrophil migration in vivo (71.2+/-16.4x10(6) and 68.8+/-10.7x10(6) PMN/cm2/24 h in patients affected by early onset periodontitis and normal subjects respectively) and in adhesion. The superoxide production in response to STZ and PMA was similar between the 2 groups, while superoxide production in response to fMLP was markedly lower in patients than in control subjects both in circulating neutrophils (5.6+/-2.2 versus 10.4+/-2.3 nmoles O2-/10(6) cells, p<0.0001) and in exudate neutrophils (16.3+/-4.3 versus 22.3+/-4.7 nmoles O2-/10(6) cells, p<0.005). In general, neutrophil function in patients suffering from early onset periodontitis does not differ from control subjects, suggesting that the overall defence function of these cells is normal. The only parameter that we have found to be different between the 2 groups is the low superoxide production after fMLP stimulation. The stimulus- and function-specificity of this defect in neutrophils from patients indicates the existence of a dysregulation of the signal transduction pathway distal to fMLP receptor and proximal to NADPH oxidase activation.
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PMID:Neutrophil migration, oxidative metabolism and adhesion in early onset periodontitis. 1048 5

Excess reactive oxygen species production is central to the development of diabetic complications. The contribution of leukocyte reactive oxygen species produced by the NADPH oxidase to altered inflammatory responses associated with uncontrolled hyperglycemia is poorly understood. To get insight into the role of phagocytic superoxide in the onset of diabetic complications, we used a model of periodontitis in mice with chronic hyperglycemia and lack of leukocyte p47(phox) (Akita/Ncf1) bred from C57BL/6-Ins2(Akita)/J (Akita) and neutrophil cytosolic factor 1 knockout (Ncf1) mice. Akita/Nfc1 mice showed progressive cachexia starting at early age and increased mortality by six months. Their lungs developed infiltrative interstitial lesions that obliterated air spaces as early as 12 weeks when fungal colonization of lungs also was observed. Neutrophils of Akita/Ncf1 mice had normal degranulation and phagocytic efficiency when compared with wild-type mice. Although Akita/Ncf1 mice had increased prevalence of oral infections and more severe periodontitis compared with wild-type mice, bone loss was only marginally higher compared with Akita and Ncf1 null mice. Altogether these results indicate that lack of leukocyte superoxide production in mice with chronic hyperglycemia results in interstitial pneumonia and increased susceptibility to infections.
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PMID:Lack of p47(phox) in Akita Diabetic Mice Is Associated with Interstitial Pneumonia, Fibrosis, and Oral Inflammation. 2674 35

Aggregatibacter actinomycetemcomitans is a Gram-negative commensal bacterium of the oral cavity which has been associated with the pathogenesis of periodontitis with severe alveolar bone destruction. The role of host factors such as reactive oxygen and nitrogen intermediates in periodontal A. actinomycetemcomitans infection and progression to periodontitis is still ill-defined. Therefore, this study aimed to analyze the role of NADPH oxidase and inducible nitric oxide synthase (iNOS) in a murine model of A. actinomycetemcomitans-induced periodontitis. NADPH oxidase-deficient (gp91phox knockout [KO]), iNOS-deficient (iNOS KO), and C57BL/6 wild-type mice were orally infected with A. actinomycetemcomitans and analyzed for bacterial colonization at various time points. Alveolar bone mineral density and alveolar bone volume were quantified by three-dimensional micro-computed tomography, and the degree of tissue inflammation was calculated by histological analyses. At 5 weeks after infection, A. actinomycetemcomitans persisted at significantly higher levels in the murine oral cavities of infected gp91phox KO mice than in those of iNOS KO and C57BL/6 mice. Concomitantly, alveolar bone mineral density was significantly lower in all three infected groups than in uninfected controls, but with the highest loss of bone density in infected gp91phox KO mice. Only infected gp91phox KO mice revealed significant loss of alveolar bone volume and enhanced inflammatory cell infiltration, as well as an increased number of osteoclasts. Our results indicate that NADPH oxidase is important to control A. actinomycetemcomitans infection in the murine oral cavity and to prevent subsequent alveolar bone destruction and osteoclastogenesis.
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PMID:NADPH Oxidase Contributes to Resistance against Aggregatibacter actinomycetemcomitans-Induced Periodontitis in Mice. 2784 81

Oral bacteria are the main trigger for the development of periodontitis, and some species are known to modulate neutrophil function. This study aimed to explore the release of neutrophil extracellular traps (NETs), associated antimicrobial proteins, and reactive oxygen species (ROS) in response to periodontal bacteria, as well as the underlying pathways. Isolated peripheral blood neutrophils were stimulated with 19 periodontal bacteria. NET and ROS release, as well as the expression of NET-bound antimicrobial proteins, elastase, myeloperoxidase, and cathepsin G, in response to these species was measured using fluorescence-based assays. NET and ROS release was monitored after the addition of NADP (NADPH) oxidase pathway modulators and inhibitors of Toll-like receptors (TLRs). Moreover, bacterial entrapment by NETs was visualized microscopically, and bacterial killing was assessed by bacterial culture. Certain microorganisms, e.g., Veillonella parvula and Streptococcus gordonii, stimulated higher levels of ROS and NET release than others. NETs were found to entrap, but not kill, all periodontal bacteria tested. NADPH oxidase pathway modulators decreased ROS production but not NET production in response to the bacteria. Interestingly, TLR inhibitors did not impact ROS and NET release. These data suggest that the variability in the neutrophil response toward different bacteria may contribute to the pathogenesis of periodontal diseases by mechanisms such as bacterial avoidance of host responses and activation of neutrophils. Moreover, our results indicate that bacterium-stimulated NET release may arise in part via NADPH oxidase-independent mechanisms. The role of TLR signaling in bacterium-induced ROS and NET release needs to be further elucidated.
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PMID:Modulation of Neutrophil Extracellular Trap and Reactive Oxygen Species Release by Periodontal Bacteria. 2894 49