Made available in DSpace on 2017-07-10T14:17:19Z (GMT). No. of bitstreams: 1 CAROLINA BOAMORTE.pdf: 1397771 bytes, checksum: 77780c428457cc0480306357b2380e44 (MD5) Previous issue date: 2016-06-16 / The ratio of osteoporosis in postmenopausal women is controversial, but may be a risk factor for periodontal disease, as well as having a direct or indirect role in bone due to estrogen action, since this can inhibit production of proinflammatory cytokines -inflammatory such as TNF-alpha and IL-6 that favor bone resorption. One of the alternatives in hormone replacement therapy is the isoflavone, a phyto-hormone that has established itself as replacement therapy for having a similar action to estrogen, but with protective effects against cancers, osteoporosis, among others. The objective was to evaluate the effect of isoflavone on alveolar bone of ovariectomized rats with induced periodontitis. Sixty (60) Female rats with 8 weeks of age were randomly divided into 6 groups: 1) control group (CON); 2) Bandage Group (LIG); 3) Group Ovariectomy (OVX); 4) Ovariectomia and Phytoestrogen group (OVX + FIT); 5) Ovariectomia and ligature group (OVX + LIG); 6) Ovariectomia Group, Phytoestrogen and Ligation (OVX + FIT + LIG) .All the animals received standard diet and water at will. After 70 days of life, the animals were anesthetized (xylazine 10 mg / kg and ketamine 75 mg / kg) and were placed in proper operating table, which allowed the maintenance of the mouth opening of the rats facilitating access to the teeth of the posterior region jaw. With the aid of a modified forceps and an explorer, it was placed a cotton yarn number 40 around the mandibular first molar right and left. After this procedure, after 79 days of life, the rats were submitted to anesthesia and ovariectomy surgery to mimic the absence of female sex hormones of menopause in women. Ligation served as irritating gums for 30 days and favored the accumulation of plaque, while hormone replacement therapy (isoflavone) was held for 21 days (0.25 g / kg / day sc) in the above-mentioned groups. At 100 days of life, the rats were euthanized. Macroscopic, microscopic and X-ray analyzes were performed with the left and right jaws of each rat as well with samples of gingival tissue to assess the periodontal tissues and their effects induced by hormone replacement. As a result of analysis, it was observed that the groups of phytoestrogen showed less bone loss than the groups that received no therapy isoflavone (p <0.05) and the treated groups had a higher phytoestrogen osteoblasts and osteocytes osteoclasts and lower than the groups not receiving hormone replacement therapy (p <0.05). Therefore, the isoflavone may confer a protective effect on bone loss in periodontal disease progression, compounded by osteoporosis. / A relação da osteoporose na pós-menopausa é controversa, mas pode ser um fator de risco para doença periodontal, bem como possuir uma atuação direta e indireta no tecido ósseo devido a ação do estrógeno, uma vez que este pode inibir a produção de citocinas pró-inflamatórias como o TNF-alfa e a IL-6 que favorecem a reabsorção óssea.Uma das alternativas na terapia de reposição hormonal atualmente é a isoflavona, um fito-hormônio que vem se estabelecendo como terapia substitutiva por ter sua ação similar ao estrógeno, porém com efeitos protetores contra as doenças cancerígenas, osteoporose, entre outras. Assim, o objetivo foi avaliar a ação da isoflavona no tecido ósseo alveolar de ratas ovariectomizadas com peridontite induzida. Sessenta (60) Ratas fêmeas com 8 semanas de vida foram divididas aleatoriamente em 6 grupos: 1) Grupo Controle (CON); 2) Grupo Ligadura(LIG); 3) Grupo Ovariectomia (OVX+DMSO); 4) Grupo Ovariectomia e Fitoestrógeno (OVX+FIT); 5) Grupo Ovariectomia e Ligadura (OVX+LIG+DMSO); 6) Grupo Ovariectomia, Fitoestrógeno e Ligadura (OVX+FIT+LIG).Todos os animais receberam dieta padrão e água a vontade. Aos 70 dias de vida, os animais foram anestesiados (xilazina 10 mg/Kg e quetamina 75 mg/Kg) e foram posicionados em mesa operatória apropriada, a qual permitia a manutenção da abertura bucal das ratas facilitando o acesso aos dentes da região posterior da mandíbula. Com o auxílio de uma pinça modificada e de uma sonda exploradora, foi colocado um fio de algodão número 40 ao redor do primeiro molar inferior direito e esquerdo. Após este procedimento, aos 79 dias de vida, as ratas também foram submetidas à anestesia e à cirurgia de ovariectomia para mimetizar a ausência de hormônios sexuais femininos da menopausa em mulheres. A ligadura atuou como irritante gengival por 30 dias e favoreceu o acúmulo de placa bacteriana, enquanto a reposição hormonal (isoflavona) se realizou por 21 dias (0,25g/kg/dia s.c.) nos grupos anteriormente citados. Aos 100 dias de vida, as ratas foram eutanasiadas. Foram realizadas análises macroscópica, microscópica e radiográfica com as mandíbulas esquerda e direita de cada rata, bem como com amostras do tecido gengival para avaliar os tecidos periodontais e seus efeitos induzidos pela reposição hormonal. Como resultado das análises, foi observado que os grupos com fitoestrógeno apresentaram menor perda óssea alveolar do que os grupos que não receberam terapia com isoflavona (p< 0,05), bem como os grupos tratados com fitoestrógeno apresentaram uma maior quantidade de osteoblastos e osteócitos e menor de osteoclastos do que os grupos que não receberam terapia de reposição hormonal (p<0,05). Logo, a isoflavona pode conferir um efeito protetor à perda óssea alveolar, na progressão da doença periodontal, agravada pela osteoporose.

Made available in DSpace on 2017-07-10T14:57:29Z (GMT). No. of bitstreams: 1 Karine _Figueredo da Costa.pdf: 1477303 bytes, checksum: 428fe0d7f49e8f5828d70fa92f05b2f1 (MD5) Previous issue date: 2015-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Background and Objective: Periodontal disease is a chronic disease that affects a major population part and has been associated with systemic changes. As a result, its relationship with obesity and atherosclerosis, it is a matter of concern for the health system.The aim of this study was to evaluate the behavior of periodontal tissues and abdominal aorta artery in rats with hypothalamic obesity associated with experimental periodontitis. Material and Methods: Twenty-eight male Wistar rats were divided , initially, into 2 groups that were subjected to intradermal injections of 4G/kg of solution of Monosodium glutamate (MSG) and 1,25G/kg/day of saline solution (group CTL)in the cervical region, in the first 5 days of life. At 70 days, the groups were subdivided into 2 another groups, where was induced periodontitis with the ligation placing in 1s lower molars; creating in this way 4 groups: control group without ligation (CTL); control group with ligation (CTL Lig); group MSG without ligation (MSG); group MSG with ligation (MSG Lig). After 100 days the rats were weighed and the naso-anal lenght was measured, so the index of Lee was determined and, then, the animals were sacrificed. Gingival tissue and abdominal aorta samples, as well as the hemi-jaws were withdrawn for immunological, morphological and radiographic analysis. Results: The interleukin-6 concentration in gingival tissue was significant in CTL Lig group, being that the Tumor Necrosis Factor-alpha concentration in the abdominal aorta is higher in groups with experimental periodontitis (p< 0.05). Both the x-ray analysis as the histology showed a lower alveolar bone loss in the MSG Lig, group when compared to the CTL Lig group (p< 0.05). In the abdominal aorta morphometric analysis there was statistically significant 48 difference in the measurement of the artery wall diameter, being the largest diameter observed in the MSG Lig group (p< 0.05). Conclusion: Therefore, this study suggests that the periodontitis in association with the hypothalamic obesity may contribute to the increase of the width of the abdominal aorta walls, as well as the hypothalamic obesity may exert a protective effect on alveolar bone loss. / Objetivo: O objetivo desse trabalho foi avaliar o comportamento de tecidos periodontais e da artéria aorta abdominal em ratos com obesidade hipotalâmica associada a periodontite experimental. A doença periodontal é uma doença crônica que afeta grande parte da população e tem sido associada a alterações sistêmicas. Sendo assim, sua relação com a obesidade e a aterosclerose, é motivo de preocupação para o sistema de saúde. Metodologia: Vinte e oito ratos Wistar foram divididos, inicialmente, em 2 grupos que foram submetidos a injeções intradérmicas na região cervical de 4g/kg/dia de solução de Glutamato Monossódico (grupo MSG) e 1,25g/kg/dia de solução salina (grupo CTL), nos primeiros 5 dias de vida. Aos 70 dias, esse grupos foram subdivididos em outros 2 grupos, onde foi induzida a periodontite com a colocação de ligadura nos 1ºs molares inferiores; originando-se assim 4 grupos: grupo controle sem ligadura (CTL); grupo controle com ligadura (CTL Lig); grupo MSG sem ligadura (MSG); grupo MSG com ligadura (MSG Lig). Aos 100 dias os ratos foram pesados e mensurados o comprimento naso-anal, assim o índice de Lee foi determinado e, então, os animais foram sacrificados. Amostras de tecido gengival e da aorta abdominal, bem como as hemi-mandíbulas foram retiradas para análises imunológicas, morfológicas e radiográficas. Resultados: A concentração de interleucina-6 no tecido gengival foi significante no grupo CTL Lig, sendo a concentração do Fator de Necrose Tumoral alfa na aorta abdominal maior nos grupos com periodontite induzida (p<0.05). Tanto a análise radiográfica quanto a histológica demonstrou uma menor perda óssea alveolar no grupo MSG Lig, quando comparado ao grupo CTL Lig (p<0.05). Na análise morfométrica da aorta abdominal houve diferença estatisticamente significante na mensuração do diâmetro das paredes da artéria, sendo o maior diâmetro observado no grupo MSG Lig (p<0.05). Conclusion: Logo, este estudo sugere que a periodontite em associação com a obesidade hipotalâmica pode contribuir para o aumento da largura das paredes da aorta abdominal, bem como a obesidade hipotalâmica pode exercer um efeito protetor sobre a perda óssea alveolar.

A doença periodontal corresponde a um grupo de doenças inflamatórias que resultam na destruição das estruturas de suporte dental. São doenças infecciosas e possuem etiologia relacionada a microrganismos gram-negativos podendo manifestar-se de inúmeras maneiras. Estes possuem uma variedade de fatores que permitem o aumento de sua virulência e capacidade de se multiplicarem e persistirem no periodonto. Experimentos recentes de nosso laboratório mostraram que no tecido gengival de rato existe a expressão de RNAm para todos os componentes do Sistema Renina-Angiotensina (SRA), presença da renina e atividade da Enzima Conversora de Angiotensina I (ECA) em tecido gengival de ratos, sugerindo, assim, possível correlação entre o SRA e a doença periodontal (DP). Portanto, o objetivo do presente trabalho foi investigar se o captopril, um inibidor da ECA, altera a progressão da DP induzida experimentalmente em ratos. Para tanto, foi utilizado o modelo de indução da DP por colocação de ligadura ao redor do primeiro molar inferior de ratos divididos em grupos com 10 animais cada, que foram tratados com captopril (via gavagem, 30 mg/kg/dia) ou água (veículo). Foi realizado pré-tratamento com esta droga por 7 ou 14 dias previamente à indução da DP e após este período, o captopril foi administrado por 14 e 21 dias. Além disso, foi realizada cirurgia fictícia para indução da DP (grupo SHAM). As técnicas utilizadas neste trabalho foram: indução da DP em ratos, extração de RNA total, transcrição reversa seguida de reação em cadeia da polimerase quantitativa (RT-qPCR) e análise de perda óssea alveolar. Os dados foram analisados por meio de gráficos. Todos os resultados foram submetidos à análise unidirecional de variância (ANOVA) e representaram médias e respectivos desvios-padrão. Diferenças entre os grupos foram consideradas estatisticamente significativas quando p < 0,05. Com base nos resultados obtidos neste trabalho, foi possível concluir que o captopril não foi capaz de diminuir a perda óssea na doença periodontal induzida experimentalmente em ratos, apesar desta droga ter alterado a expressão de RNAm para um alvo do RAS (AT1a) e alguns mediadores do processo inflamatório no tecido periodontal, tais como COX-2, ECA-2, IL-6, RANKL, VEGF-R1 e VEGF-R2. / Periodontal disease (PD) consists of a group of inflammatory diseases which result in the destruction of tooth supporting structures. They are of infectious nature, with etiological factors related to gram-negative microorganisms, and may have manifestations in several ways. These comprise a variety of factors that allow the increase in its virulence and ability to multiply and persist in the periodontal tissue. Recent findings form our laboratory showed that mRNA expression exists in rat gingival tissue for all components of the Renin-Angiotensin System (RAS), the presence of renin as well as Angiotensin Converting Enzyme I (ACE) activity in rat gingival tissue, thus suggesting a possible correlation between the RAS and periodontal disease. Therefore, the aim of this study was to investigate whether captopril, an ACE inhibitor, alters the progression of experimentally-induced PD in rats. Thus, the model of PD induction by ligature placement around rat lower first molar was used. Animals were divided groups of 10 animals each, which were treated with captopril (via gavage, 30 mg/kg/day) or water (vehicle). Pre-treatment with this drug during 7 or 14 days was performed previously to PD induction, and after this period captopril was administered during 14 or 21 days. In addition, fictitious operation (SHAM group) was performed to induce PD. The techniques used in this study were: PD induction in rats, total RNA extraction, reverse transcriptionquantitative polymerase chain reaction (RT-qPCR) and alveolar bone loss. Data were analyzed by means of graphs. All the results were subjected to one-way analysis of variance (ANOVA) and represented means and respective standard errors. Differences between groups were considered statistically significant when p <0.05. Based on the results obtained in this study, it was concluded that captopril was not able to decrease bone loss in experimentally-induced PD in rats, although this drug altered the expression of mRNA for one RAS target (AT1a) and some mediators of inflammation in periodontal tissue such as, COX-2, ACE-2, IL-6, RANKL, VEGF-R1 and VEGF-R2.

O receptor ativado por protease do tipo 1 (PAR1) parece estar associado ao reparo periodontal, enquanto o tipo 2 (PAR2) com a inflamação periodontal. Esses receptores podem ser ativados pelas proteases gingipaina, uma protease secretada pela Porphyromonas gingivalis, um importante periodontopatógeno, e pela proteinase-3 de neutrófilos (P3), que é liberada por neutrófilos quando expostos a um estímulo inflamatório. Uma vez que o diabetes é reconhecido como um fator de risco importante para a doença periodontal, o objetivo deste estudo foi investigar a expressão de PAR1 e de PAR2 e de seus ativadores, gingipaina e P3 no fluido gengival (FG) de pacientes diabéticos com periodontite crônica, antes e após tratamento periodontal não cirúrgico. Amostras de FG e os parâmetros clínicos, como profundidade de sondagem (PS), nível clínico de inserção (NCI), sangramento à sondagem (SS) e índice de placa (IP) foram coletados de pacientes sistemicamente saudáveis e de pacientes com diabetes mellitus do tipo 2 (DMT2) com periodontite crônica , no baseline e após o tratamento periodontal não cirúrgico. As expressões gênicas de PAR1, PAR2, gingipaina e P3 no FG foram quantificadas por qPCR. Os parâmetros clínicos melhoraram significativamente após a terapia periodontal (p <0,01). O diabetes levou ao aumento da expressão de PAR1 no fluido gengival e na presença da periodontite crônica diminuiu significativamente a expressão de PAR1, PAR2 e P3 (p<0,05). Além disso, o tratamento periodontal não cirúrgico em diabéticos resultou no aumento da expressão de PAR1 e de PAR2 (p<0,05). Dentro dos limites do presente estudo, sugerimos que os PARs podem estar associados com a inflamação periodontal em diabéticos. / Protease activated receptor type 1 (PAR1) seems to play a role in periodontal repair, while PAR2 is associated with periodontal inflammation. These receptors can be activated by gingipain, a protease released from Porphyromonas gingivalis, an important periodontal pathogen, and neutrophil proteinase-3 (P3), which is released by neutrophils when exposed to an inflammatory stimulus. Since diabetes is known risk factor to periodontal disease, the aim of this study was to investigate PAR1 and PAR2 mRNA expression at the gingival crevicular fluid (GCF) in diabetic patients with chronic periodontitis, before and after non-surgical periodontal treatment. GCF samples and clinical parameters consisting of measuring probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP) and plaque index (PI) were collected from systemically healthy patients and patients with type 2 diabetes mellitus with chronic periodontitis, at baseline and after nonsurgical periodontal treatment. PAR1 and PAR2, as well the expression of the activators gingipain and P3 at the GCF were quantified by qPCR. The clinical parameters improved significantly after periodontal therapy (p <0.01). Diabetes led to increased expression of PAR1 in the GCF, and the presence of chronic periodontitis significantly decreased the expression of PAR1, PAR2 and P3 (p <0.05). Moreover, non-surgical periodontal treatment in diabetics resulted in increased expression of PAR1 and PAR2 (p <0.05). Within the limits of this study, we suggest that PARs may be associated with periodontal inflammation in diabetics.

Periodontitis is an infective disease caused predominantly by gram negative anaerobic bacteria. However it is apparent that alveolar bone loss, which characterises periodontitis, is a result of the host inflammatory response to pathogenic bacteria, not the infectious agents directly. Omega-3 polyunsaturated fatty acids (O-3 PUFAs) are recognised, and used widely, for their anti-inflammatory effects. Evidence is emerging that their oxygenated derivatives are key chemical mediators in the resolution of inflammation. We hypothesised that dietary supplementation with fish oil rich in the O-3 PUFA docosahexaenoic acid would modify inflammatory reactions within the periodontium and thus reduce alveolar bone loss in mice infected with periodontopathic bacteria. Eighty mice were fed experimental diets containing either 10% tuna oil (40) or a sunola oil (40) which contained no traceable O-3 PUFAs for 57 days. After two weeks each dietary set was split into four groups of ten mice, with these groups being inoculated with either a) Porphyromas gingivalis b) P. gingivalis and Fusobacterium nucleatum (combined inoculum) c) Carboxymethylcellulose (control) or d) No inoculations (control). Of the twenty mice which received no inoculations, half were sacrificed after fifteen days and half at the end of the experiment to enable comparative fatty acid analysis of the oral soft tissues. Results demonstrated that eicosapentoic acid and docosahexaenoic acid were found in significantly higher proportions in the oral soft tissues of mice fed a tuna oil diet, and that animals receiving this diet exhibited an average of 54 - 72% less alveolar bone resorption in response to the different bacterial infections. Irrespective of diet, the combined inoculum resulted in slightly more alveolar resorption than P. gingivalis alone. The findings of this study suggest that fish oil dietary supplementation may have potential benefits as a host modulatory agent in the adjunctive management of periodontitis. Given its advantages in terms of safety, cost effectiveness and widespread availability, this dietary supplement warrants further research in human trials to assess its ability to modulate alveolar bone loss in individuals with periodontitis. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1313252 / Thesis (D.Clin.Dent.) - University of Adelaide, School of Dentistry (Periodontics), 2008

Fusobacterium nucleatum is a saccharolytic Gram-negative anaerobic organism belonging to the so-called ‘orange complex’ which is believed to play an important role in the microbial succession associated with the pathogenesis of periodontal disease. Its genome contains niche-specific genes shared with the other inhabitants of dental plaque, which may help to explain its ability to survive and grow in the changing environmental conditions experienced in the gingival sulcus during the progression from health to disease. The pH of the gingival sulcus increases during the development of periodontitis and is thought to occur by the metabolism of nutrients supplied by gingival crevicular fluid. Studies have shown that F. nucleatum is partly responsible for the rise in pH and have concluded that in comparison to other plaque inhabitants, F. nucleatum has the greatest ability to neutralise acidic environments. In common with a number of other oral bacteria, F. nucleatum has also been shown to produce intracellular polyglucose (IP) from simple sugars such as glucose, galactose and fructose. Its response and adaptation to stressful environmental conditions such as pH is unknown. The overall aim of this study was, therefore, to determine how F. nucleatum copes with environmental stresses induced by pH changes. F. nucleatum was grown by continuous culture in a chemically defined medium at a growth rate corresponding to those measured in vivo. The effect on protein expression, and IP synthesis was examined during steady-state growth at high (>7.2<7.8) or low pH (pH 6.4). The present study also investigated the response of F. nucleatum to growth at pH 8.2. It was found that the organism grew as a biofilm and this corresponded with an increase in cellular hydrophobicity and decreased IP levels. Optimal growth pH’s differed between the different sub-species used in this study. In response to pH stress, F. nucleatum changed its amino acid and glucose utilisation and increased IP synthesis at the expense of cell numbers. Pulsing the chemostat with glutamic acid or serine produced an increase in IP synthesis and the pattern of end-products observed was dependent upon the amino acid being fermented. The effect on IP synthesis in response to increased levels of exogenous fermentable amino acids was also compared during concomitant fructose or glucose fermentation. Growth media containing fermentable amino acids and supplemented with fructose produced higher cell numbers and non-detectable levels of IP compared to media containing glucose. The differential expression of cytoplasmic- and cell envelope-proteins induced by changes in pH were identified by two-dimensional gel electrophoresis. The results represent the first proteomic investigation of F. nucleatum. Twenty-two cytoplasmic proteins were found to have altered expression in response to external pH. At low (sub-optimal) pH, proteins associated with the generation of ATP and ammonia were up-regulated, the latter contributing to the alkalinisation of the gingival sulcus. Conversely, neutral to alkaline pH conditions led to the upregulation of enzymes involved in energy storage. The study also identified several proteins associated with iron limitation and fatty acid synthesis which might not otherwise have been identified as part of the pH-dependent response. In response to growth at pH 7.8, 14 cell envelope proteins were identified as having significantly altered expression. Down-regulated proteins included those associated with uptake of C4 di-carboxylates and phosphorus, a potential membrane protease and an enzyme associated with amino acid fermentation. The up-regulation of a transcriptional regulator linked to the repression of sugar metabolism was also reported along with proteins linked to the transport of iron. The periplasmic chaperone, peptidyl prolyl cis trans isomerase, which is responsible for the folding of outer membrane proteins, was also found to be up-regulated. In conclusion, the proteomic investigation of protein expression by F. nucleatum identified gene products which form part of the organism’s coordinated stress response to changes in environmental pH. In addition to these, the physiological based studies also presented help to explain the organism’s persistence during the transition from health to disease in vivo. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1339503 / Thesis (Ph.D.) - University of Adelaide, Dental School, 2008

Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 4 uppsatser.

Thesis (M.S.)--University of Michigan, 1981.

Thesis (M.S.)--University of Michigan, 1983.

Thesis (M.S.)--University of Michigan, 1981.