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The effect of volatile thiol compounds on permeability of oral mucosaNg, William Man Fai January 1986 (has links)
Cumulative clinical and experimental evidence indicates that volatile sulphur compounds (VSC) the principal components of oral malodour, may play an important role in the pathogenesis of periodontal disease. As their (H₂S and CH₃SH) concentrations in gingival sulci increase with the severity of periodontal involvement, the objective of this investigation is to ascertain if they exert an effect on the permeability of oral mucosa.
Permeability determinations were performed on excised porcine sublingual mucosal specimens which consisted of non-keratinized epithelium, basal membrane and connective tissue layers mounted in a two compartment perfusion apparatus. Using radioactive and fluorescent-labelled penetrants, it was found that exposure of the epithelial surface to an atmosphere containing physiological concentrations of both thiols (15 ng H₂S or CH₃SH / ml of 95% air - 5% C0₂) increased the permeability of the mucosa to (³⁵S)-S0₄⁻², (³H)-prostaglandin E₂ (PGE₂) and fluorescein isothiocyanate labelled E. coli lipopolysaccharide (F-LPS). A three hour exposure of the mucosa to H₂S and CH₃SH resulted in a 75% and 103% increase respectively in permeability to (³⁵S)-labelled sulphate ion. Similarly, the mercaptan induced up to a 70% increase in permeability of the mucosa to (³H)-prostaglandin E₂. The
magnitude of changes in the permeability were found to depend on duration of exposure to the thiols and to their concentration. Studies using (³⁵S)-H₂S suggest that the observed changes in the tissue permeability are related to the reaction of the thiols with tissue components. In addition, the (³⁵S)-H₂S is capable of perfusing through all three layers of the mucosa at 12.3 ng / cm². In contrast to H₂S , the CH₃SH effect was irreversible in
control air / C0₂ environment. This infers that CH₃SH is
potentially a more deleterious agent to the tissue barrier. However, its effect can also be reversed by treatment of tissues with 0.22% ZnCl₂ either prior to or after exposure to mercaptan.
This suggests that Zn⁺² ion may be useful in preventing the potentially harmful effects of VSC.
Fluorescent studies with F-LPS indicate that thiols can also potentiate the penetration of endotoxin. Whereas the fluorescence of the F-LPS in control systems was confined to the superficial
epithelial layer in contact with the endotoxin, the CH₃SH-
exposed mucosa exhibited fluorescence throughout the epithelial and connective tissue layers. Fluorescent staining of the mucosal specimens with fluorescein diacetate followed by counter staining with ethidium bromide provides evidence of membrane impairment to some cells by CH₃SH. Collectively these
observations provide strong experimental evidence that the VSC, products of putrefaction produced in the gingival sulcus by oral microflora, may adversely affect the integrity of the crevicular barrier to deleterious agents and thus contribute to the etiology of periodontal disease. / Dentistry, Faculty of / Graduate
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Optimization of porcine buccal mucosa for in vitro evaluationKulkarni, Upendra D. 01 January 2007 (has links)
Porcine buccal mucosa has been extensively used as in vitro model to study the permeability of drugs and assess their potential to deliver through buccal route. Porcine buccal mucosa is found to be very similar to human oral mucosa in structure and function. However, the in vitro permeation studies across porcine buccal mucosa show high variability which is mostly due to the various experimental and biological variables that are often overlooked while conducting such studies.
The precise nature of the permeability barrier offered by the various tissue layers of buccal mucosa was investigated in this study. It was observed that the permeability of model diffusants decreased significantly with an increase in the connective tissue layer. However, the epithelium offered a stronger barrier to permeation of all diffusants studied at mucosal thickness of up to 500 |tm. The epithelium acted as a stronger barrier for hydrophilic diffusants when compared to lipophilic diffusants.
It was also observed that the permeability of model diffusants was significantly higher in the region behind lip when compared to the middle cheek region which is due to lower epithelial thickness in that region. Porcine buccal mucosa retained its integrity in Kreb's bicarbonate Ringer solution at 4 °C for 24 hours and many other storage conditions resulted in loss of epithelial integrity. Separation of epithelium from the underlying connective tissue by heat treatment, did not adversely affect its permeability and integrity characteristics.
Influence of experimental temperature on the permeability of model compounds across porcine buccal mucosa was also investigated in vitro. An exponential relationship was observed between the apparent permeability and temperature. It was found that the activation energy of diffusion of the model compounds decreased linearly with increasing distribution coefficients across porcine buccal mucosa. This suggested that the buccal mucosa acted as a stronger barrier for diffusion of hydrophilic diffusants when compared to the lipophilic diffusants.
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Cellular and molecular biomarkers detected in the oral mucosa and saliva in water-pipe tobacco smoking compared to cigarette smoking: A systematic reviewDalia, Elamin January 2021 (has links)
Magister Chirurgiae Dentium (MChD) / Water-pipe tobacco smoking (WTS) is a form of tobacco use with different names. There is a misconception that passing tobacco smoke through water reduces its harmful effects to increase its popularity. One million individuals smoke water-pipe daily, resulting in approximately five million deaths per annum globally. The toxic effects of WTS are related to the several components of the tobacco mixture. WTS contains 100 times more tar, four-fold more nicotine, eleven-fold more Carbon Monoxide (CO), and two to five-fold more polycyclic aromatic hydrocarbons than cigarettes.
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Investigation for the Identification of Transient Amplifying/Stem Cell Pool in Oral MucosaJabero, Marvin Frank 14 September 2010 (has links)
No description available.
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Repercussões morfológicas dos efeitos da subnutrição protéica pré e pós-natal e da renutrição pós-natal sobre a mucosa palatina de ratos Wistar na fase púbere: avaliações morfométricas e da expressão do IGF-I e IGF-IR e da insulina e seu receptor / Morphologic repercussions of the protein malnutrition pre and postnatal and postnatal refeeding on the palatal mucosa of Wistar rats in the pubescent phase: structural evaluations and the expressions of the IGF-I and IGF-IR, Insulin and your receptorVono, Diana de Oliveira 17 February 2012 (has links)
Atualmente reagrupou-se sob o nome de subnutrição calórico-protéica uma série de afecções de carência antigamente descritas com diversos nomes e que tinham uma etiologia comum, a insuficiência alimentar, acarretando, ao mesmo tempo um emagrecimento e um esgotamento progressivo do estoque de proteínas do organismo. A partir de alterações na quantidade e qualidades dos alimentos ingeridos, o organismo busca regular seu metabolismo visando atingir a homeostase, na qual os hormônios desempenham papel fundamental. Dessa maneira, a desnutrição protéica e a secreção de insulina foram aqui correlacionados na avaliação morfológica e funcional do epitélio oral, representando, respectivamente, grave alteração nutricional (à semelhança da que acomete a população, especialmente, de países subdesenvolvidos e em desenvolvimento) e resposta produzida pela alteração do metabolismo energético das células. Os fatores de crescimento insulino-símile tipos 1 e 2 (IGF-I e IGF-II) são os principais fatores endócrinos determinantes do crescimento fetal. A maioria das ações conhecidas do IGF-I é mediada via um receptor tirosina-quinase, conhecido como IGF-IR. Recentemente, a insensibilidade ao IGF-I foi identificada como uma das causas de retardo de crescimento sem recuperação espontânea do desenvolvimento na vida pós-natal. Sendo assim, o presente trabalho tem o objetivo de estudar, através de métodos morfométricos, na mucosa palatina de ratos Wistar na fase púbere submetidos à desnutrição protéica pré e pós-natal e a renutrição pós-natal, o padrão celular e o componente colágeno da lâmina própria, bem como a expressão do IGF-I, do IGF-IR e da insulina e seu receptor, no intuito de encontrar possível correspondência entre as alterações metabólicas e morfofuncionais, decorrentes da depleção protéica. Para tanto, foram formados os seguintes grupos experimentais constituídos por animais heterogênicos (n=3) de acordo com a ração oferecida, protéica ou hipoprotéica: nutridos (N) e desnutridos (D) com 60 dias de idade, por ser essa a fase do final do período púbere, e renutridos (R), formado por animais do grupo D que, a partir do 21º dia (época do desmame) foram submetidos à ração protéica até atingirem 60 dias de idade. Os espécimes foram processados rotineiramente para microscopia de luz (HE, Azo-carmin e Pircro-sírius) e para imunohistoquímica (IGF-I, IGF-IR e insulina e seu receptor) e os dados morfoquantitativos analisados estatisticamente. Os resultados demonstraram que os parâmetros metabólicos tais como: alimentar, massa corporal, excreção de fezes, urina e ingestão de água, diferiram em todos os grupos semana após semana (S1≠S2≠S3≠S4≠S5≠S6). A densidade de células epiteliais fora constatada pelo método de coloração H.E. e imunomarcadas com insulina e IGF-I e seus respectivos receptores. A subnutrição determinou um aumento significativo de células reativas a insulina (I) e seu receptor (IR) em relação ao grupo renutrido e nutrido (I: S ≠R; p<0.05) e (IR: S≠N; S≠R; p<0.05). O grupo R não obeteve aumento significativo de células imunomarcadas, assim, diferiu significativamente em relação ao grupo N para os hormônios IGF-I e seu receptor IGF-IR (R≠N;p<0.05). O número de células da mucosa palatina modifica-se pouco na fase púbere e o seu desenvolvimento normal é sensível à depleção protéica, de modo que o tecido não é capaz de responder ao restabelecimento protéico. / Currently it has been grouped and named protein-caloric under nutrition a series of deficiency described in the past under several denominations with similar etiology, the food deficiency which leads simultaneously to a weight loss and progressive decrease of protein storage in the body. From the changes in the quantity and quality of ingested food, the organism tries to regulate its metabolism in order to homeostasis, in which the hormones play a fundamental role. This way, the protein under nutrition and the insulin secretion were here correlated in the morphological and functional evaluation of the oral epithelium representing high nutritional change (similarly to one which affect people specially from under developed countries) and response produced by changes in the energetic metabolism of the cells respectively. The grown factors insuline-símile type 1 and 2 (IGF-I and IGF-II) are the principal endocrine factors which determine the fetal growth. Many known actions of the IGF-I are mediated via tyrosine-kinase receptor known as IGF-IR. Recently, the insensibility to IGF-I was identified as one of the reason for the regrowth without abrupt recovery of the development in the post-natal life. Therefore, the present work aims to study, the cellular standard and the collagen of lamina propria, as well as the expression of the IGF-I, of the IGF-IR and the insulin and its receptor, using morphometric methods in the palatine mucosa of wistar rats in the pubertal phase subject to protein under nutrition pre and post natal and post-natal re-feeding with the objective of finding possible association between metabolic and morph functional changes coming from protein depletion. For this purpose, the following experimental groups were formed: heterogenic animals (n=3) according to the diet offered protein or hyperprotein diet: nourished (N) and undernourished (D) with 60 days of age (finish of pubertal phase), and re-nourished (R), formed by animals of D group that, from the 21st day (weaning day) were subject to protein diet up to 60 days of age. The specimens were processed routinely for light microscopy (HE, Azo-carmin and Pircro-sírius) and for immunohistochemistry (IGF-I, IGF-IR and insulin and its receptor) and the morph quantitative data statistically analyzed. The results demonstrate that the metabolic parameters such as: food, body mass, feces excretion, urine and water ingestion differ in all groups weekly (S1≠S2≠S3≠S4≠S5≠S6). The density of epithelial was observed by HE method and immune-marked with insulin and IGF-I and their respective receptors. The under nutrition determined a significant increase of the cells reacting to insulin (I) and its receptor (IR) in relation to re-nourished and nourished groups (I: S ≠R; p<0.05) and (IR: S≠N; S≠R; p<0.05). No significant increase of immune-marked cells was observed in the R group, thus, differing significantly when comparing to N group for the hormones IGF-I and its receptor IGF-IR (R≠N;p<0.05). The number of palatine mucosal cells has changed little in the pubertal phase and its normal development is sensitive to protein depletion, so the tissue cannot respond to the protein replacement.
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Tissue Engineering Of Full-thickness Human Oral MucosaKinikoglu, Beste F. 01 December 2010 (has links) (PDF)
Tissue engineered human oral mucosa has the potential to fill tissue deficits caused by facial trauma or malignant lesion surgery. It can also help elucidate the biology of oral mucosa and serve as an alternative to in vivo testing of oral care products. The aim of this thesis was to construct a tissue engineered full-thickness human oral mucosa closely mimicking the native tissue. To this end, the feasibility of the concept was tested by co-culturing fibroblasts and epithelial cells isolated from normal human oral mucosa biopsies in a collagen-glycosaminoglycan-chitosan scaffold, developed in our laboratory to construct a skin equivalent. An oral mucosal
equivalent closely mimicking the native one was obtained and characterized by histology, immunohistochemistry and transmission electron microscopy. Using the same model, the influence of mesenchymal cells on oral epithelial development was investigated by culturing epithelial cells on lamina propria, corneal stroma and dermal equivalents. They were found to significantly influence the thickness and the ultrastructure of the epithelium. Finally, in order to improve the adhesiveness of conventional scaffolds, an elastin-like recombinamer (ELR) containing the cell adhesion tripeptide, RGD, was used in the production of novel bilayer scaffolds employing lyophilization and electrospinning. These scaffolds were characterized by
mercury porosimetry, scanning electron microscopy and mechanical testing. In vitro tests revealed positive contribution of ELR on the proliferation of both fibroblasts and epithelial cells. It was thus possible to construct a viable oral mucosa equivalent using the principles of tissue engineering.
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Zur Kasuistik des Schleimhautlupus und des Lupuskarzinoms im Bereiche der MundhöhleJansen, Hendrik J. January 1937 (has links)
Inaug.--Diss.--Münster, 1937. / Includes bibliographical references (p. 89-101).
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Uso do LED vermelho em mucosite induzida por quimioterapia /Sacono, Nancy Tomoko. January 2007 (has links)
Resumo: A mucosite é uma das complicações orais mais incidentes relacionadas à quimioterapia, que provoca ulcerações, dor, dificuldade de alimentação e pode levar à interrupção do tratamento antineoplásico. O objetivo deste estudo foi testar o efeito do LED (Ligth Emitting Diode) no tratamento da mucosite induzida por quimioterapia em hamsters. Os animais do grupo experimental (G1) e do grupo controle (G2) receberam injeção de 5-fluoruracila nos dias 0 e 2 do experimento e tiveram as mucosas direita e esquerda arranhadas nos dias 3 e 4. O G1 recebeu tratamento com LED (630 nm, 160 mW, 12 J/cm2) durante 37,5 segundos nos dias 3, 4, 6, 8, 10, 12 e 14. A mucosa jugal foi evertida e fotografada a cada dois dias a partir do dia 4 até o dia 14. As fotografias foram classificadas por meio de uma escala de acordo com o grau de severidade da mucosite (0 a 5). O G2 não recebeu tratamento. O grupo controle negativo (G3) não foi submetido à indução de mucosite. Nos dias 5, 9, 13 e 14, as mucosas de 8 animais (G1 e G2) foram removidas para avaliação histopatológica. A análise estatística demonstrou haver diferenças significantes entre o grupo tratado com LED e o grupo não tratado (p<0,05) quando se comparou a severidade da mucosite, apesar de a avaliação histopatológica ter demonstrado degeneração muscular em aproximadamente 18% da amostra (G1). A aplicação do LED nos parâmetros utilizados neste estudo foi efetiva na redução da severidade da mucosite oral e na cicatrização das lesões, embora não tenha prevenido completamente o surgimento das mesmas. / Abstract: Mucositis is the most common oral complication of cancer chemotherapy that causes pain and impairs patient's ability to eat, swallow and may determine interruption of the treatment. The aim of this study was to evaluate the effect of LED (Ligth Emitting Diode) therapy on chemotherapy-induced mucositis in hamsters. The animals of both experimental (G1) and positive control group (G2) received intraperitoneal injections of 5-fluorouracil on days 0 and 2. All animals had right and left oral mucosa irritated by superficial scratching on days 3 and 4. The G1 received LED irradiation (630 nm, 160 mW, 12 J/cm2) during 37,5 seconds at days 3, 4, 6, 8, 10, 12 and 14. The cheek pouches were everted and photographed from day 4 until 14 at 2-day intervals. Photographs were randomly scored according to the severity of induced mucositis (0 to 5). The G2 received no treatment. The negative control group (G3) received no mucositis induction. The cheek pouches of 8 animals (G1 and G2) were dissected for histopathological examination on days 5, 9, 13 and 15. The statistical analysis showed significant differences between treated and non-treated groups (p<0,05), although histopathological findings have demonstrated muscular degeneration in 18% of the sample (G1), approximately. These results pointed out that LED therapy protocol established for this study was effective to reduce the severity of oral mucositis and accelerated the healing process, although it has not completely prevented the appearance of oral lesions. / Orientador: Fabio Cesar Braga de Abreu e Lima / Coorientador: Carlos Alberto de Souza Costa / Banca: Elisa Maria Aparecida Giro / Banca: Rosane de Fátima Zanirato Lizarelli / Mestre
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Avaliação dos efeitos do consumo de etanol, da cessação do consumo e do co-tratamento com vitamina E em parâmetros de estresse oxidativo e na atividade proliferativa da língua de ratosCarrard, Vinícius Coelho January 2008 (has links)
O objetivo do presente estudo foi avaliar os efeitos dos consumos agudo e crônico de etanol, da sua cessação e do co-tratamento com vitamina E em parâmetros de estresse oxidativo na mucosa e na atividade proliferativa no epitélio lingual de ratos. Após realizar-se uma revisão de literatura, observou-se que o acúmulo de acetaldeído (um metabólito do etanol), o polimorfismo das enzimas que metabolizam o álcool e o estresse oxidativo poderiam ser mecanismos envolvidos na patogênese do dano pelo álcool na mucosa bucal, sendo o estresse oxidativo escolhido como tema do estudo. Uma amostra de 48 ratos Wistar, fêmeas, com 3 meses, foram divididos em 6 grupos (álcool, álcool cessação, álcool vitamina E, controle, tween e vitamina E). O grupo tween recebeu solução de 5% de Tween 80 (veículo da vitamina E) por meio de gavagem enquanto os outros animais receberam solução salina. Após 14 dias os animais foram anestesiados e uma biópsia foi realizada no centro do dorso da língua. Esse material foi utilizado para análise do efeito do consumo agudo de etanol e do co-tratamento com vitamina E em parâmetros de estresse oxidativo (TBARS, grupos carbonil, atividade das enzimas antioxidantes superóxido dismutase-SOD e catalase-CAT e relação SOD/CAT). Após 60 dias de experimento, os animais do grupo álcool cessação tiveram o álcool substituído por água. Após 120 dias, os animais foram mortos e as línguas foram removidas. Esse material foi utilizado para a avaliação de parâmetros de estresse oxidativo (TBARS, grupos carbonil, SOD, CAT e relação SOD/CAT, imunoconteúdos da CAT e do Nrf2), da atividade proliferativa (AgNORS) e da possível relação entre ambos. Os animais submetidos ao tratamento agudo com álcool mostraram redução dos níveis de TBARS. A atividade da CAT foi mais alta no grupo álcool vitamina E após o tratamento agudo. O consumo crônico de etanol induziu aumento da atividade proliferativa no epitélio do ventre da língua quando comparado ao grupo controle. Esse efeito foi atenuando pela cessação do consumo. Além disso, houve aumento da atividade da CAT e diminuição dos níveis de TBARS nesse grupo. O grupo álcool vitamina E mostrou maior atividade proliferativa em relação ao grupo vitamina E e maior atividade da SOD, indicando que o co-tratamento com vitamina E não teve efeito protetor nos tecidos linguais. Conclui-se que o aumento da proliferação relacionado ao álcool no epitélio lingual não está associado ao estresse oxidativo. Uma vez que o dano provocado pelo álcool foi revertido, é possível sugerir que o álcool atua como um promotor de câncer bucal. / The aim of the present study was to evaluate the effects of acute and chronic alcohol consumption, alcohol consumption cessation and vitamin E cotreatment on rats tongue mucosa oxidative stress parameters and on tongue epithelium proliferative activity. After to conduce a literature review it was observed that acetaldehyde accumulation (an alcohol metabolite), the polimorphism of alcohol metabolization enzymes and oxidative stress could be mechanisms related to pathogenesis of alcohol damage in oral mucosa, and the former was choosen for the study. Forty-eight Wistar rats, female, 3 months-old were separated into 6 groups (alcohol, alcohol cessation, alcohol vitamin E, control, vitamin E, tween, vitamin E). The tween group received 5% tween 80 (vitamin E vehicle) by gavage, and the other animals received saline. At day 14, the animals were anesthetized and a biopsy was performed on tongue dorsum. In this sample, it was evaluated the acute alcohol consumption and vitamin cotreatment effects on oxidative stress parameters (thiobarbituric acid reactive substances-TBARS, carbonyl groups, superoxide dismutase activity-SOD and catalase activity-CAT and SOD/CAT ratio). After 60 days, 40% (v/v) ethyl alcohol was replaced with water in the alcohol cessation group. Vitamin E was given by gavage to animals in the alcohol/vitamin E and vitamin E groups. After 4 months, the animals were killed and the tongue was removed. Cell proliferation rate was evaluated using AgNOR quantification in histological sections. Oxidative stress parameters (TBARS, carbonyl groups, SOD and CAT, CAT and Nrf2 immunocontent) were quantified in tongue homogenates as well as the association between oxidative parameters and cell proliferation. The animals subjected to acute alcohol treatment showed TBARS decrease. SOD activity was lower and CAT activity was higher in alcohol and vitamin E group after acute treatment. Chronic alcohol consumption induced increase in cell proliferation rates of ventral tongue epithelium when compared to the Control group. This effect was attenuated after alcohol cessation. In addition, an imbalance of superoxide dismutase and catalase activities and decrase in TBARS were found in this group. The alcohol/vitamin E group showed higher proliferation rate than the Vitamin E group, suggesting that vitamin E cotreatment had no protective effects on the tongue tissues. It was concluded that the alcohol-related cell proliferation increase in tongue epithelium is not associated to oxidative stress parameters. Since the alcohol damage was reversible, it is possible to suggest that alcohol acts as an oral cancer promoter.
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Avaliação dos efeitos do consumo de etanol, da cessação do consumo e do co-tratamento com vitamina E em parâmetros de estresse oxidativo e na atividade proliferativa da língua de ratosCarrard, Vinícius Coelho January 2008 (has links)
O objetivo do presente estudo foi avaliar os efeitos dos consumos agudo e crônico de etanol, da sua cessação e do co-tratamento com vitamina E em parâmetros de estresse oxidativo na mucosa e na atividade proliferativa no epitélio lingual de ratos. Após realizar-se uma revisão de literatura, observou-se que o acúmulo de acetaldeído (um metabólito do etanol), o polimorfismo das enzimas que metabolizam o álcool e o estresse oxidativo poderiam ser mecanismos envolvidos na patogênese do dano pelo álcool na mucosa bucal, sendo o estresse oxidativo escolhido como tema do estudo. Uma amostra de 48 ratos Wistar, fêmeas, com 3 meses, foram divididos em 6 grupos (álcool, álcool cessação, álcool vitamina E, controle, tween e vitamina E). O grupo tween recebeu solução de 5% de Tween 80 (veículo da vitamina E) por meio de gavagem enquanto os outros animais receberam solução salina. Após 14 dias os animais foram anestesiados e uma biópsia foi realizada no centro do dorso da língua. Esse material foi utilizado para análise do efeito do consumo agudo de etanol e do co-tratamento com vitamina E em parâmetros de estresse oxidativo (TBARS, grupos carbonil, atividade das enzimas antioxidantes superóxido dismutase-SOD e catalase-CAT e relação SOD/CAT). Após 60 dias de experimento, os animais do grupo álcool cessação tiveram o álcool substituído por água. Após 120 dias, os animais foram mortos e as línguas foram removidas. Esse material foi utilizado para a avaliação de parâmetros de estresse oxidativo (TBARS, grupos carbonil, SOD, CAT e relação SOD/CAT, imunoconteúdos da CAT e do Nrf2), da atividade proliferativa (AgNORS) e da possível relação entre ambos. Os animais submetidos ao tratamento agudo com álcool mostraram redução dos níveis de TBARS. A atividade da CAT foi mais alta no grupo álcool vitamina E após o tratamento agudo. O consumo crônico de etanol induziu aumento da atividade proliferativa no epitélio do ventre da língua quando comparado ao grupo controle. Esse efeito foi atenuando pela cessação do consumo. Além disso, houve aumento da atividade da CAT e diminuição dos níveis de TBARS nesse grupo. O grupo álcool vitamina E mostrou maior atividade proliferativa em relação ao grupo vitamina E e maior atividade da SOD, indicando que o co-tratamento com vitamina E não teve efeito protetor nos tecidos linguais. Conclui-se que o aumento da proliferação relacionado ao álcool no epitélio lingual não está associado ao estresse oxidativo. Uma vez que o dano provocado pelo álcool foi revertido, é possível sugerir que o álcool atua como um promotor de câncer bucal. / The aim of the present study was to evaluate the effects of acute and chronic alcohol consumption, alcohol consumption cessation and vitamin E cotreatment on rats tongue mucosa oxidative stress parameters and on tongue epithelium proliferative activity. After to conduce a literature review it was observed that acetaldehyde accumulation (an alcohol metabolite), the polimorphism of alcohol metabolization enzymes and oxidative stress could be mechanisms related to pathogenesis of alcohol damage in oral mucosa, and the former was choosen for the study. Forty-eight Wistar rats, female, 3 months-old were separated into 6 groups (alcohol, alcohol cessation, alcohol vitamin E, control, vitamin E, tween, vitamin E). The tween group received 5% tween 80 (vitamin E vehicle) by gavage, and the other animals received saline. At day 14, the animals were anesthetized and a biopsy was performed on tongue dorsum. In this sample, it was evaluated the acute alcohol consumption and vitamin cotreatment effects on oxidative stress parameters (thiobarbituric acid reactive substances-TBARS, carbonyl groups, superoxide dismutase activity-SOD and catalase activity-CAT and SOD/CAT ratio). After 60 days, 40% (v/v) ethyl alcohol was replaced with water in the alcohol cessation group. Vitamin E was given by gavage to animals in the alcohol/vitamin E and vitamin E groups. After 4 months, the animals were killed and the tongue was removed. Cell proliferation rate was evaluated using AgNOR quantification in histological sections. Oxidative stress parameters (TBARS, carbonyl groups, SOD and CAT, CAT and Nrf2 immunocontent) were quantified in tongue homogenates as well as the association between oxidative parameters and cell proliferation. The animals subjected to acute alcohol treatment showed TBARS decrease. SOD activity was lower and CAT activity was higher in alcohol and vitamin E group after acute treatment. Chronic alcohol consumption induced increase in cell proliferation rates of ventral tongue epithelium when compared to the Control group. This effect was attenuated after alcohol cessation. In addition, an imbalance of superoxide dismutase and catalase activities and decrase in TBARS were found in this group. The alcohol/vitamin E group showed higher proliferation rate than the Vitamin E group, suggesting that vitamin E cotreatment had no protective effects on the tongue tissues. It was concluded that the alcohol-related cell proliferation increase in tongue epithelium is not associated to oxidative stress parameters. Since the alcohol damage was reversible, it is possible to suggest that alcohol acts as an oral cancer promoter.
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