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A matriz démica acelular, MDA, figura dentre os biomateriais que têm por objetivo restaurar defeitos mucogengivais. A correção de defeitos mucogengivais a partir de constituintes autógenos são os procedimentos mais comumente usados, no entanto, em decorrência da quantidade insuficiente de tecido doador, esses procedimentos se tornam limitados. Diante disso, o objetivo desse estudo foi avaliar, in vitro, diferentes aspectos relacionados ao cultivo prévio de fibroblastos gengivais humanos em MDA. Fibroblastos gengivais humanos foram cultivados pela técnica do explante a partir de amostras de tecido gengival queratinizado removido de três pacientes saudáveis. A MDA foi cultivada com esses fibroblastos por períodos de 14 e 21 dias para posterior análise dos eventos de: adesão celular, proliferação e viabilidade. Os resultados mostraram que em 7 dias, os fibroblastos estavam aderidos, espraiados e dispersos sobre a superfície externa da MDA, em 14 dias formavam monocamada de células de morfologia alongada e quiescentes (Ki-67 negativos) em sua maioria, sendo apenas ocasionalmente observadas no interior da MDA. Em 21 dias a monocamada exibia menor densidade celular. Os resultados sugerem que o cultivo de fibroblastos em MDA em períodos de 14 dias permite boas condições de adesão e espraiamento das células sobre a matriz, porém, a alta densidade de fibras colágenas parece ser um fator limitante à migração celular. / Acellular Dermal Matrix, ADM, is a biomaterial that has been used in periodontal procedures to treat mucogingival defects. Mucogingival defects can be corrected by autogenous grafts that are the most common procedure used in periodontology, however, because of the limited source of donor\'s tissue this procedure became limited. The aim of this investigation was to verify, in vitro, different aspects related to human gingival fibroblasts seeding on to the ADM. Human gingival fibroblasts were established from explant cultures from the connective tissue of keratinized gingiva collected from three healthy patients. ADM was seeded with gingival fibroblasts for 14 and 21 days, and then cell adherence, proliferation and viability were analyzed. Results revealed that, at day 7, fibroblasts were adherent and spreading on the ADM surface, and were unevenly distributed, forming a discontinuous single cell layer, at day 14, a confluent fibroblastic monolayer lining ADM surface was noticed. At day 21, the cell monolayer exhibited a reduction in cell density. The results suggests that fibroblasts seeding on the ADM for 14 days can allow good conditions for cell adhesion and spread on the matrix, however, because of the high collagen fiber bundle density cell, migration inside the matrix was limited.

A matriz démica acelular, MDA, figura dentre os biomateriais que têm por objetivo restaurar defeitos mucogengivais. A correção de defeitos mucogengivais a partir de constituintes autógenos são os procedimentos mais comumente usados, no entanto, em decorrência da quantidade insuficiente de tecido doador, esses procedimentos se tornam limitados. Diante disso, o objetivo desse estudo foi avaliar, in vitro, diferentes aspectos relacionados ao cultivo prévio de fibroblastos gengivais humanos em MDA. Fibroblastos gengivais humanos foram cultivados pela técnica do explante a partir de amostras de tecido gengival queratinizado removido de três pacientes saudáveis. A MDA foi cultivada com esses fibroblastos por períodos de 14 e 21 dias para posterior análise dos eventos de: adesão celular, proliferação e viabilidade. Os resultados mostraram que em 7 dias, os fibroblastos estavam aderidos, espraiados e dispersos sobre a superfície externa da MDA, em 14 dias formavam monocamada de células de morfologia alongada e quiescentes (Ki-67 negativos) em sua maioria, sendo apenas ocasionalmente observadas no interior da MDA. Em 21 dias a monocamada exibia menor densidade celular. Os resultados sugerem que o cultivo de fibroblastos em MDA em períodos de 14 dias permite boas condições de adesão e espraiamento das células sobre a matriz, porém, a alta densidade de fibras colágenas parece ser um fator limitante à migração celular. / Acellular Dermal Matrix, ADM, is a biomaterial that has been used in periodontal procedures to treat mucogingival defects. Mucogingival defects can be corrected by autogenous grafts that are the most common procedure used in periodontology, however, because of the limited source of donor\'s tissue this procedure became limited. The aim of this investigation was to verify, in vitro, different aspects related to human gingival fibroblasts seeding on to the ADM. Human gingival fibroblasts were established from explant cultures from the connective tissue of keratinized gingiva collected from three healthy patients. ADM was seeded with gingival fibroblasts for 14 and 21 days, and then cell adherence, proliferation and viability were analyzed. Results revealed that, at day 7, fibroblasts were adherent and spreading on the ADM surface, and were unevenly distributed, forming a discontinuous single cell layer, at day 14, a confluent fibroblastic monolayer lining ADM surface was noticed. At day 21, the cell monolayer exhibited a reduction in cell density. The results suggests that fibroblasts seeding on the ADM for 14 days can allow good conditions for cell adhesion and spread on the matrix, however, because of the high collagen fiber bundle density cell, migration inside the matrix was limited.

Estudos relataram a atividade antimicrobina de Equisetum giganteum e Punica granatum, reduzindo o risco do desenvolvimento da estomatite protética, doença relacionada principalmente à colonização das próteses pelo fungo Candida albicans. Diante disso, é necessário que essas plantas sejam bem toleradas pelos tecidos bucais e, se possível, auxiliem no processo de reparo. Objetivo: Realizar um estudo fitoquímico de substâncias potencialmente ativas de Equisetum giganteum e Punica granatum e avaliar a viabilidade de fibroblastos gengivais humanos frente a diferentes concentrações destas plantas, após diferentes períodos in vitro. Material e Métodos: Após a identificação dos compostos das plantas por HPLC-PAD, foram selecionadas as frações com melhor atividade antifúngica perante Candida albicans. Os extratos brutos e frações selecionadas de P. granatum e E. giganteum foram testados em diferentes concentrações (0.23, 0.47, 0.94, 1.88, 3.75, 7.5, 15 e 30 mg) e períodos (12, 24, 36 e 60 h) sobre fibroblastos gengivais humanos (FGH), para a avaliação de suas citotoxicidades através da análise da viabilidade dos FGH, pelo ensaio LIVE/DEAD. Por meio desse ensaio, analisamos quantitativamente a viabilidade celular através das leituras das unidades relativas de fluorescência (URF) e qualitativamente por meio da analise da morfologia e da densidade observadas pela microscopia invertida de fluorescência, após três experimentos independentes para cada período de avaliação. Os resultados quantitativos paramétricos foram representados como média e desvio padrão (SD) com análise de Variância ANOVAOne- Way, seguida da análise comparativa pelo teste de Tukey HSD. Os resultados quantitativos não paramétricos foram apresentados como mediana e quartis e foram submetidos ao teste de Kruskal-Wallis, seguido de análise comparativa pelo teste de Dunn, de acordo com as análises de normalidade (Teste de Kolmogorov-Smirnov). Valores de p< 0.05 foram indicativos de significância estatística. Conclusões: Foram identificados compostos fenólicos, como flavonoides e taninos em E.giganteum e P. granantum, respectivamente. Identificamos uma citotoxicidade concentração-dependente para as duas plantas testadas, independente do tempo. Sob as menores concentrações das plantas a viabilidade e a morfologia dos FGH foram preservadas. Dentro deste contexto, acreditamos na possibilidade de se utilizar essas plantas como terapia alternativa em diversas áreas de saúde, porém em concentrações biocompatíveis. / Studies have reported the antimicrobial activity of Equisetum giganteum and Punica granatum, reducing the risk of development of denture stomatitis, a disease mainly related to the colonization of prostheses by the fungus Candida albicans. In view of this, it is necessary that these plants be well tolerated by the oral tissues and, if possible, assist in the repair process. Objective: To carry out a phytochemical study of potentially active substances of E. giganteum and P. granatum and to evaluate the viability of human gingival fibroblasts against different concentrations of these two plants, after different periods in vitro. Material and Methods: After the identification of the plant compounds by HPLC-PAD, the fractions with the best antifungal activity against Candida albicans were selected. The crude extracts and selected fractions of P. granatum and E. giganteum were tested at different concentrations (0.23, 0.47, 0.94, 1.88, 3.75, 7.5, 15 and 30 mg) and periods (12, 24, 36 and 60 h) against human gingival fibroblasts (FGH), for the evaluation of their possible cytotoxicity through the analysis of the viability of FGH by the LIVE/DEAD assay. By means of this assay we quantitatively analyzed the cell viability through the readings of the relative units of fluorescence (URF) and qualitatively by analysis of the cellular morphology and density using inverted fluorescence microscopy, after three independent experiments. The parametric quantitative results were represented as mean and standard deviation (SD) with ANOVA-One-Way Variance analysis, followed by comparative analysis by the Tukey HSD test. The non-parametric quantitative results were presented as medians and quartiles and were submitted to the Kruskal-Wallis test, followed by comparative analysis by the Dunn test, according to normality tests (Kolmogorov-Smirnov test). Values of p <0.05 were indicative of statistical significance. Conclusions: Phenolic compounds, such as flavonoids and tannins, were identified in E. giganteum and P. granantum, respectively. We identified a concentration-dependent cytotoxicity for the two plants tested, regardless of the time. Under the lowest concentrations of plants the viability and morphology of FGH were preserved when compared to the control. Within this context, we believe in the possibility to use these plants as alternative therapy in several health areas, but in biocompatible concentrations.

Estudos relataram a atividade antimicrobina de Equisetum giganteum e Punica granatum, reduzindo o risco do desenvolvimento da estomatite protética, doença relacionada principalmente à colonização das próteses pelo fungo Candida albicans. Diante disso, é necessário que essas plantas sejam bem toleradas pelos tecidos bucais e, se possível, auxiliem no processo de reparo. Objetivo: Realizar um estudo fitoquímico de substâncias potencialmente ativas de Equisetum giganteum e Punica granatum e avaliar a viabilidade de fibroblastos gengivais humanos frente a diferentes concentrações destas plantas, após diferentes períodos in vitro. Material e Métodos: Após a identificação dos compostos das plantas por HPLC-PAD, foram selecionadas as frações com melhor atividade antifúngica perante Candida albicans. Os extratos brutos e frações selecionadas de P. granatum e E. giganteum foram testados em diferentes concentrações (0.23, 0.47, 0.94, 1.88, 3.75, 7.5, 15 e 30 mg) e períodos (12, 24, 36 e 60 h) sobre fibroblastos gengivais humanos (FGH), para a avaliação de suas citotoxicidades através da análise da viabilidade dos FGH, pelo ensaio LIVE/DEAD. Por meio desse ensaio, analisamos quantitativamente a viabilidade celular através das leituras das unidades relativas de fluorescência (URF) e qualitativamente por meio da analise da morfologia e da densidade observadas pela microscopia invertida de fluorescência, após três experimentos independentes para cada período de avaliação. Os resultados quantitativos paramétricos foram representados como média e desvio padrão (SD) com análise de Variância ANOVAOne- Way, seguida da análise comparativa pelo teste de Tukey HSD. Os resultados quantitativos não paramétricos foram apresentados como mediana e quartis e foram submetidos ao teste de Kruskal-Wallis, seguido de análise comparativa pelo teste de Dunn, de acordo com as análises de normalidade (Teste de Kolmogorov-Smirnov). Valores de p< 0.05 foram indicativos de significância estatística. Conclusões: Foram identificados compostos fenólicos, como flavonoides e taninos em E.giganteum e P. granantum, respectivamente. Identificamos uma citotoxicidade concentração-dependente para as duas plantas testadas, independente do tempo. Sob as menores concentrações das plantas a viabilidade e a morfologia dos FGH foram preservadas. Dentro deste contexto, acreditamos na possibilidade de se utilizar essas plantas como terapia alternativa em diversas áreas de saúde, porém em concentrações biocompatíveis. / Studies have reported the antimicrobial activity of Equisetum giganteum and Punica granatum, reducing the risk of development of denture stomatitis, a disease mainly related to the colonization of prostheses by the fungus Candida albicans. In view of this, it is necessary that these plants be well tolerated by the oral tissues and, if possible, assist in the repair process. Objective: To carry out a phytochemical study of potentially active substances of E. giganteum and P. granatum and to evaluate the viability of human gingival fibroblasts against different concentrations of these two plants, after different periods in vitro. Material and Methods: After the identification of the plant compounds by HPLC-PAD, the fractions with the best antifungal activity against Candida albicans were selected. The crude extracts and selected fractions of P. granatum and E. giganteum were tested at different concentrations (0.23, 0.47, 0.94, 1.88, 3.75, 7.5, 15 and 30 mg) and periods (12, 24, 36 and 60 h) against human gingival fibroblasts (FGH), for the evaluation of their possible cytotoxicity through the analysis of the viability of FGH by the LIVE/DEAD assay. By means of this assay we quantitatively analyzed the cell viability through the readings of the relative units of fluorescence (URF) and qualitatively by analysis of the cellular morphology and density using inverted fluorescence microscopy, after three independent experiments. The parametric quantitative results were represented as mean and standard deviation (SD) with ANOVA-One-Way Variance analysis, followed by comparative analysis by the Tukey HSD test. The non-parametric quantitative results were presented as medians and quartiles and were submitted to the Kruskal-Wallis test, followed by comparative analysis by the Dunn test, according to normality tests (Kolmogorov-Smirnov test). Values of p <0.05 were indicative of statistical significance. Conclusions: Phenolic compounds, such as flavonoids and tannins, were identified in E. giganteum and P. granantum, respectively. We identified a concentration-dependent cytotoxicity for the two plants tested, regardless of the time. Under the lowest concentrations of plants the viability and morphology of FGH were preserved when compared to the control. Within this context, we believe in the possibility to use these plants as alternative therapy in several health areas, but in biocompatible concentrations.

Oral Submucous Fibrosis (OSF) is a chronic inflammatory disease resulting in progressive fibrosis of the oral tissues that can cause difficulty in chewing, swallowing, speaking, and mouth opening. Epidemiological studies have shown that OSF is a precancerous condition and 2-8% of the OSF patients develop squamous cell carcinoma. This disease affects 0.5% of the population in the Indian subcontinent and is now a growing public health issue in many parts of the world. Habit of chewing betel quid has been proposed as an important etiological factor in the development of this disease and is coline, a principle alkaloid of areca nut is considered as major causative factor for OSF development. But the exact molecular mechanism of OSF pathogenesis is not known. Therefore, we set the following objectives for this study: 1) Gene expression profiling of OSF using microarray. 2) Role of areca nut constituents in OSF pathogenesis. 3) Effect of areca nut on epithelial and fibroblast cells. In order to delineate the possible molecular mechanism of OSF pathogenesis, we took microarray approach and identified differentially regulated genes in ten OSF tissues against eight pooled normals using whole human genome oligonucleotide arrays. Microarray results revealed differential expression of 5288 genes (p≤0.05 and Fold change≥1.5), among them 2884 were up-regulated and 2404 were down-regulated. Validation employing quantitative real-time PCR and immunohistochemistry confirmed up-regulation of transforming growth factor-β1 (TGF-β1), TGFBI, THBS1, SPP1, TIG1 and down-regulation of bone morphogenic protein 7 (BMP7), C4orf7 and ALOX12 in OSF tissues. Furthermore, activation of TGF-β pathway was evident in OSF tissues as demonstrated by p-SMAD2 strong immunoreactivity. Analysis of IHC data showed that in all the normal tissues and in 70% of the OSF tissues the expression of TGF-β and BMP7 are inversely correlated. In good correlation, treatment of keratinocytes (HaCaT) by TGF-βdown-regulated BMP7, while BMP7 expression could not be detected in fibroblast cells. Hence, the imbalance between TGF-βand BMP7 signalling, which are positive and negative modulators of extracellular matrix production, respectively may trigger the manifestation of OSF. We also studied the regulation few genes (CTGF, TGM2 and THBS1) identified in OSF microarray in response to TGF-βand arecoline. TGF-βwas able to induce all the above genes in both HaCaT and hGF cells but arecoline could only induce TGM2 in hGF and THBS1 in HaCaT. Therefore TGF-βpathway came out to be the most important pathway in OSF microarray and subsequent validations. But areca nut constituents responsible for TGF-βpathway activation and the source (epithelial or fibroblast cells) through which it activates TGF-βare not known. In an attempt to understand the role of areca nut and its constituents in inducing TGF-βsignalling in epithelial cells, we performed microarray on epithelial cells (HaCaT) treated with areca nut water extract. Surprisingly, 64% of the differentially regulated genes by areca nut water extract matched with TGF-βinduced gene expression profile. To find out areca nut induced genes through TGF-β, epithelial cells were treated with areca nut in presence of ALK5 (TβRI) inhibitor. Out of 64% differentially induced genes, 57% genes induced by areca nut got compromised in presence of ALK5 and 7% were independently induced by areca nut, highlighting the effect of areca nut via TGF-β. Accordingly, areca nut treatment induced both p-SMAD2 and TGF-βdownstream targets TGFBI, TGM2, TMEPAI and THBS1 in HaCaT cells. One possible mechanism of TGF-βsignalling induction by areca nut could be via induced ligand (TGF-β2) and its activator (THBS1). Induction of TGF-β2 ligand by areca nut was shown at both RNA (Real Time) and protein (ELISA) levels. To find out areca nut components responsible for inducing TGF-β signalling, areca nut fractionation was performed which gave three fractions namely, Ethyl acetate (polyphenol), water supernatant (alkaloids) and Dichloromethane (impurity). Out of these; polyphenol and alkaloid fractions were found to be responsible for the induction of TGF-β signalling and its downstream targets. Upon treatment with purified components, catechin and tannin of polyphenol fraction and arecoline, arecaidine and guvacine of alkaloid fraction were found to be responsible for inducing TGF-β signalling, as seen by increased appearance of phopho-SMAD2 in HaCaT cells. Areca nut treatment on human gingival fibroblast cells (hGF) did not induce TGF-β signalling, highlighting that the source of TGF-β induction by areca nut could possibly be the epithelium. Further treatment of areca nut along with TGF-β on hGF cells potentiated TGF-β effect both in terms of TGF-β downstream targets like TGFBI, TGM2, TMEPAI, COL1A1 etc and activation of fibroblast by inducing α-SMA. Increasing concentration of areca nut is cytotoxic on HaCaT cells and pro-proliferative on hGF cells. This could provide a possible explanation for epithelial atrophy and proliferating fibroblast cells in connective tissue of OSF patients. Further exploration on HaCaT cell cytotoxicity by areca nut suggests the involvement of Reactive Oxygen Species (ROS) as a key molecule induced by areca nut. Compromising ROS generation by NAC (N-Acetyl-L-Cysteine) led to reversal of Sub-G1 peak induced by areca nut in HaCaT cells. This highlighted that cell death caused by areca nut could be ROS mediated. Areca nut treatment on hGF cells did not induce ROS generation, leading to no cytotoxicity on these cells. A possible explanation of this differential ROS generation can be due to dose dependent suppression of Catalase activity by areca nut in HaCaT cells but not in hGF cells. We also compared cytotoxicity of areca nut with all the alkaloids and found a good match with arecoline as both of them induce ROS, apoptotic ladder formation, annexin V positivity, suppression of Catalase activity and the cell death induced by them was compromised by NAC. The above results indicated that arecoline could be a mediator of areca nut water extract cytotoxicity on HaCaT cells. Betel nut chewer’s oral epithelium gets regularly exposed to areca nut and hence this exposure could be cytotoxic to oral epithelial cells too. We performed Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) in normal and OSF tissues. Our data showed 62.5% of OSF patients having significant percentage of epithelial cells with TUNEL positivity (Labeling index = 2-60%) compared to all normal tissues that were TUNEL negative. TUNEL positivity was predominantly seen in the upper keratin and supra basal layer of the epithelium. We also studied proliferation status of OSF epithelium and observed that 3-17% (LI) of epithelial cells in all normal tissues showed Ki-67 positivity in the germinal layer of epithelium. However, 65% of the OSF patients showed staining for Ki-67 (LI=.2-58%) in their epithelium. Also analysis of TUNEL positive and Ki-67 positive sections indicated that OSF patients with high TUNEL positivity have high Ki-67 labeling index, but stains in the supra basal or keratin layer (TUNEL) and basal layer (Ki-67) of epithelium respectively. This induced proliferation of epithelial cells could be the result of heavy apoptosis in the outer epithelium. But as these patients are regularly exposed to areca nut, this increased proliferation may not be able to cope up with the heavy apoptosis induced by areca nut, leading to atrophied epithelium. To understand the germinal status of OSF atrophied epithelium we performed staining for OCT4 in OSF tissues. To our surprise there were no OCT4 positive nuclei in the epithelium of 53% of OSF patients but a regular spread of OCT4 positivity has been seen in the epithelium of normal subjects. In conclusion, this thesis highlights the involvement of TGF-β pathway in OSF patho-physiology. In addition, activation of TGF-β pathway by areca nut constituents has been demonstrated. Moreover, the atrophied epithelium of OSF appears to be a consequence of apoptosis and stem cell deprivation. Taken together, areca nut perhaps causes atrophy of the epithelium and activates TGF-β pathway that may lead to manifestation of OSF.