Les galactofuranoconjugués, bien que xénobiotiques chez les mammifères, sont des constituants cruciaux de la paroi cellulaire de nombreux micro-organismes pathogènes. La présence de ces motifs font des galactofuranoconjugués des cibles de choix pour le développement d’outils de lutte ou de diagnostic contre ces micro-organismes et leurs maladies associées. Au cours de ces travaux de thèse, une nouvelle stratégie de synthèse utilisant une α-Larabinofuranosidase, capable de reconnaître un mime du motif D-galactofuranose a été utilisée, la CtAraf51 de Ruminiclostridium thermocellum. Des premiers travaux de mutagénèse ont été entrepris, afin d’améliorer l’affinité de l’enzyme pour le motif non naturel D-Galf, sur trois résidus acides aminés de la poche catalytique, identifiés par des études de modélisation. La création de banques de mutants, le criblage de leur activité et la détermination des paramètres cinétiques nous ont permis d’identifier plusieurs mutants à fort potentiel pour le développement d’une néogalactufuranosidase. Dans le but d’étendre l’activité de l’enzyme à d’autres réactions que l’hydrolyse, l’autocondensation et la transglycosylation, un second axe de recherche a été exploré. La mise au point d’une réaction standard à partir du mutant thioglycoligase et le crible d’accepteurs nucléophiles ont permis d’identifier de nouvelles réactions de thioligation et d’acylation. Enfin les deux axes de recherche ont été mis en commun et ont permis de synthétiser de nouveaux S- et O-galactofuranoconjugués de manière efficace par voie biocatalytique. / Galactofuranoconjugates, while xenobiotic in mammals, are crucial constituents on the cell walls of pathogenic microorganisms. The presence of these patterns, in these microorganisms, makes them molecular targets for the development of tools to fight or prevent the associated diseases. This work describes a new strategy to access galactofuranoconjugates mimetic, using an α-Larabinofuranosidase, the CtAraf51 from Ruminiclostridium Thermocellum. Initial mutagenesis work was undertaken, to improve the affinity of the enzyme for the unnatural DGalf motif. Three amino acid residues in the catalytic pocket were identified by modeling studies and subsequently mutated. The screening of activity of the resulting mutants and the determination of kinetic parameters allowed us to identify several mutants with high potential for the development of a néogalactufuranosidase. A second area of research has been explored with the aim to extend the activity of the enzyme to others reactions than hydrolysis, self-condensation and transglycosylation. The optimization of standard condition from the thioglycoligase mutant and the screening of nucleophilic acceptors has led to the identification of new thioligation and acylation reactions. Finally, the two previous researches were combined in order to synthesize new S- and Ogalactofuranoconjugates in an efficient way.

No description available.

Les travaux menés au cours de cette thèse s’inscrivent dans le cadre général de l’évaluation du terme source (relâchement de gaz de fission) en situation incidentelle de type APRP (Accident de Perte de Réfrigérant Primaire). Lors de tels transitoires thermiques, le relâchement de gaz de fission se fait par bouffées successives : une première entre 600°C et 800°C et la seconde à environ 1100°C. Ces travaux de thèse s’intéressent à cette première. Il semblerait que la bouffée à 600-800°C proviendrait du centre de la pastille combustible. L’objectif de cette thèse est d’étudier les mécanismes à l’origine de cette bouffée.Afin de mieux comprendre ces mécanismes, une étude a été menée sur l’ensemble des traitements thermiques réalisés dans la plateforme expérimentale MERARG. L’analyse de cette base de données a révélé 2 points importants : 1) Dans les conditions expérimentales de MERARG, aucune fagmentation significative du combustible n’est observée à des températures inférieures à 1000°C. 2) Le niveau de relâchement de gaz de fission entre 600°C et 800°C semble augmenter avec le temps d’entreposage du combustible.Le premier point indique que la fragmentation du combustible n’est pas une condition nécessaire au relâchement de gaz de fission dans cette gamme de température : d’autres mécanismes peuvent être à l’origine de ce relâchement. Durant l’entreposage, le combustible est soumis principalement à l’auto-irradiation α. Celle-ci a pour effet de créer des défauts dans une zone qui n’en contenait initialement pas. Nous avons démontré que la cinétique du relâchement de gaz de fission entre 600°C et 800°C est concomitante avec la cinétique de recuit de défauts d’autoirradiation α. De plus, une cinétique auto-catalytique de germination-croissance de nano-clusters de gaz a été développée et confrontée aux résultats expérimentaux. En outre, une étude sur matériaux simulants démontre que, sur des pastilles d’UO2 frittées et implantées en xénon, une irradiation en régime électronique a pour effet d’accroitre le relâchement entre 600°C et 800°C. La littérature décrit la remise en solution des bulles de gaz de fission sous l’effet d’une irradiation de ce type. De plus, lors de leur remise en solution, les gaz de fission s’insèrent dans les défauts de la structure cristalline. Lors d’un traitement thermique, le recuit des défauts entraine la mobilité des atomes de gaz de fission insérés de ces mêmes défauts. Par germination-croissance, les paires gaz/défauts rejoignent un chemin de sortie, les gaz de fission sont donc relâchés.Ce travail a donc permis de retenir l’hypothèse d’un mécanisme de relâchement de gaz de fission entre 600°C et 800°C par recuit de défauts sans fragmentation significative du combustible. / The subject of this thesis concerns the evaluation of the source term (fission gas release) in incidental situations of type LOCA (Loss of Coolant Accident) of nuclear fuels. During such thermal transients, the fission gas release is characterized by successive bursts : the first one occurring between 600 and 800°C, and a second one at about 1100°C. This work is about the first burst release. It appear that this one come from the centre of the fuel pellet. The aim of this thesis is to study the mechanisms responsible for the fission gas release between 600°C and 800°C.To this purpose, we collected more than 200 results of thermal treatments carried out using the experimental platform MERARG. The analysis of this database reveals two important results : under the experimental conditions of MERARG, no significant fragmentation of the fuel was observed at temperatures below 1000°C ; the amount of fission gas release between 600°C and 800°C appears to increase with fuel storage time.The first result suggests the fragmentation of the fuel is not a necessary condition for the release of fission gas in this temperature range. Other mechanisms may then be responsible for this gas release. During its storage, the fuel undergoes α particle self-irradiation. We demonstrate that the kinetics of fission gas release between 600°C and 800°C is simultaneous with the kinetics of the annealing of self-irradiation defects at this same temperature. The mechanism involves an autocatalytic process leading to a kinetic of fast germination-growth of gas nano-clusters. This model perfectly explains the experimental results in the database. To confirm this mechanism, a study on surrogate materials demonstrates that, in UO2 pellets sintered and implanted by Xe, irradiations in the electronic regime actually promote the release of implanted Xe at those temperatures. The re-dissolution of the fission gas bubbles by this kind of irradiation is consistent with observations in other contexts. Those conclusions allow to extend the mechanism for release to irradiated fuel.During the storage of the fuel, α self-irradiation promotes the re-dissolution of the trapped gas. The consequences of this effect are particularly important in the region close to the grain boundaries, where the concentration of defects is also larger. The irradiation mechanism increases the fraction of fission gas available for release, depleting the amount of gas initially trapped in bubbles. The gas in solution can effectively be carried by crystal defects, largely available in the irradiated fuel and whose migration at 600-800°C induces the mobility of the fission gas. When they reach an outlet path, the gas can be released from the pellet in a way consistent with the model of autocatalytic germination-growth we developed to explain the macroscopic results of the database.In conclusion, this work supports the hypothesis of a mechanism of fission gas release in the range 600-800°C via a mechanism involving the migration and annealing of defects without significant fragmentation of the fuel.

The interactions of 5,6- and 6,7-dihydroxy derivatives of 2-aminotetralin with [3H]clonidine and [3H]clonidine and [3H]prazosin as well as with [3H]spiperone binding sites in rat cerebral cortex membrane preparations were investigated. The hydroxy derivatives of 2-aminotetralin tested showed significant interaction with [3H]clonidine as well as with [3H]spiperone binding sites while for [3H]prazosin binding site these agents appeared virtually inactive. For interaction with [3H]clonidine binding site 6,7-dihydroxy substitutions impart greater potency that 5,6-dihydroxy substitutions and N-alkyl substitutions either make no difference or reduce the affinity of these compounds. N-alkyl substitutions, however, markedly enhance the affinity of 5,6-dihydroxy derivatives for interactions with [3H]spiperone binding site. The results suggest that some hydroxy derivatives of aminotetralin have significant interaction with both central α2-adrenoceptor and D2-dopamine receptor systems.

Fermentation and roasting of cocoa (Theobroma cacao) decrease levels of polyphenolic flavanol compounds. However, it is largely unknown how these changes in polyphenol levels caused by processing affect cocoa's anti-diabetic and anti-obesity bioactivities, such as inhibition of certain enzymes in the body. Polyphenol profiles, protein-binding abilities, presence of compounds termed oxidative polymers, and abilities to inhibit α-glucosidase, pancreatic α-amylase, lipase, and dipeptidyl peptidase-IV (DPP4) in vitro were compared between unfermented bean (UB), fermented bean (FB), unfermented liquor (UL), and fermented liquor (FL) cocoa extracts. Overall, there were significant decreases (p<0.05) in total polyphenols, flavanols, and anthocyanins between the two sets of unfermented and fermented cocoa extracts (CEs). All CEs effectively inhibited α-glucosidase (lowest IC50 = 90.0 ug/mL for UL) and moderately inhibited α-amylase (lowest IC50=183 ug/mL for FL), lipase (lowest IC25=65.5 ug/mL for FB), and DPP4 (lowest IC25=1585 ug/mL for FB) in dose-dependent manners. Fermentation and roasting of the samples affected inhibition of each enzyme differently (both processes enhanced α-amylase inhibition). Improved α-glucosidase and α-amylase inhibitions were correlated with presence of different classifications of oxidative polymers, suggesting that these compounds could be contributing to the bioactivities observed. Some α-glucosidase inhibition might be due to non-specific protein-binding. Improved DPP4 inhibition was strongly correlated to increased CE degree of polymerization. In conclusion, potential enzyme inhibition activities of cocoa were not necessarily negatively affected by the large polyphenol losses that occur during fermentation and roasting. Additionally, it is possible that more complex compounds could be present in cocoa that contribute to its potential anti-diabetic and anti-obesity bioactivities. / Master of Science in Life Sciences

La première partie de cette thèse présente un rapide historique de l’iode hypervalent et de ses caractéristiques. Par la suite les réactions d’α-oxydation de cétones et de déaromatisation oxydative seront abordées. Le premier chapitre présente ma première publication sur des travaux commencés par Audrey-Anne Guilbault sur des iodoaryloxazolines et leur utilisation de façon catalytique pour la préparation d’α-tosyloxy cétones énantioenrichies. Le second chapitre s’intéresse à ma seconde publication qui présente une méthode alternative pour préparer des α-tosyloxy cétones à partir d’acétates d’énol et ainsi circonvenir à une partie des problèmes rencontrés avec l’utilisation de cétones. Le dernier chapitre concerne ma troisième publication et présente l’utilisation d’une famille d’espèces d’iode C2 symétriques chirales existantes et leur utilisation avec les acétates d’énol pour atteindre des excès énantiomérique record pour la synthèse d’α-tosyloxy cétones en utilisant l’iode hypervalent. La dernière partie résume ce qui a été appris au travers de ces études en utilisant l’iode hypervalent puis des pistes concernant des travaux futurs seront évoquées.

Nanopores have been shown to be a useful analytical tool for single molecule detection. They have been used to study the composition of DNA and other molecules of interest. These pores are usually α-hemolysin which is a toxin from Staphylococcus aureus or more recently nanoscale synthetic solid state pores. Now we are beginning to look at other molecules or proteins by sending them into the nanopores and measuring a characteristic partial current blockade. In this thesis we look at polyethylene glycol (PEG) as it enters and blocks current through a single alpha hemolysin pore. We report the effects of ionic strength, PEG size, and applied voltage on the depth and duration of the current blockades. We also apply autocorrelation analysis on the arrival times of PEG molecules to the pore see if we can identify if the PEG is translocating through the pore or escaping from the same side it enters. This suggests a new approach to current blockade analysis.

The involvement of the pro-inflammatory cytokine, tumour necrosis factor alpha (TNF-α) and the sympathetic nervous system in the development of delayed-onset muscle soreness has not been established. I assessed the effect of etanercept, a TNF- α inhibitor, and atenolol, a β1-receptor antagonist, on DOMS induced in the quadriceps muscle. Thirteen male subjects reported to the exercise laboratory on three separate occasions, 6-15 weeks apart. In a randomised, double-blind cross-over format, I administered etanercept (25mg), atenolol (25mg) or placebo, one hour before the exercise. Subjects then completed four sets of 15 repetitions at 80% of their one repetition maximum (1RM) on a 45° inclined leg press machine. Muscle strength changes were detected by remeasuring the subject’s 1RM 24h, 48h and 72h after the exercise. Sensitivity to pressure of the quadriceps muscle was measured using a pressure algometer before and 24h, 48h and 72h after exercise. The subject’s perception of the pain was measured with the visual analogue scale and McGill Pain Questionnaire. Muscle tumour necrosis factor-alpha concentration was measured before exercise and then 2h and 24h after exercise in four subjects. Muscle strength was impaired 24h and 48h after exercise regardless of agent administered (P < 0.001). At 72h after exercise, muscle strength was significantly improved (P < 0.01) in subjects receiving etanercept and atenolol compared to those receiving placebo. The subject’s were significantly more sensitive to pressure applied to the quadriceps 24h, 48h and 72h after exercise compared to before exercise, regardless of agent administered (P < 0.001). The VAS was elevated significantly at all three time intervals, with no difference after etanercept or atenolol administration compared to that of placebo. There was no significant difference in the muscle TNF-α concentration between any of the time intervals or between subjects receiving placebo and etanercept (P=0.065). The administration of atenolol and etanercept, at the regimen used, had no effect on the soreness associated with DOMS.

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No. of bitstreams: 3 license_text: 21328 bytes, checksum: 683d9883b2ad62ac3b8bafc566b2e600 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) 2015LucianaKnabbendeOliveiraBeckerDelving.pdf: 1574790 bytes, checksum: b751dea1371239a23970a2767f3789ba (MD5) / Na medicina tradicional, as plantas tem sido utilizadas para o tratamento de diversas doenças ao longo dos séculos e são consideradas uma das maiores fontes para o desenvolvimento de novas drogas. Com o objetivo de contribuir com o conhecimento cientifico no estudo e desenvolvimento de novas drogas procurou-se com este trabalho, identificaros principais constituintes fitoquímicosda Calyptranthes grandifolia, avaliar seus potenciais citotóxicos e antioxidantes e também identificar e avaliar o efeito terapêutico, através de vias específicas e já conhecidas por seu envolvimento no processo inflamatório, como o TNF- α. Para todos os experimentos, foram utilizados extratos etanólico e hexânico das folhas da C.grandifolia, coletada no entorno do município de Lajeado.Foi realizada a análise fitoquímica de esteroides/terpenoides, taninos, flavonoides, cumarinas, quinonas, alcaloides e saponinas, utilizando metodologias descritas na literatura. O potencial citotóxico in vitro foi avaliado pelo método de Alamar Blue, utilizando células não metabolizadoras CHO-K1 e a atividade antioxidante foi realizada pelo método2,2-difenil-1-picrilhidrazila (DPPH). A análise da liberação do TNF-α utilizou células RAW 264.7, tratadas com os extratos vegetais e posterior estimulação com lipopolissacarídeo (LPS). A quantificação de liberação do TNF-α foi feita pelo método de ELISA. Os resultados dos ensaios indicaram a presença de esteroides/terpenoides, taninos e flavonoides no extrato etanólico. O potencial citotóxico, não apresentou citotoxicidade considerável no extrato etanólico e manteve a viabilidade celular aumentada na maioria das concentrações, com uma diminuição não significativa da viabilidade em 200 μg/mL, de forma semelhante para o extrato hexânico a redução da viabilidade celular pode ser observada somente na concentração de 200 μg/mL. A atividade antioxidante esteve presente apenas no extrato etanólico de maneira dose-dependente, com IC50 de 21.3±1.7μg/mL.O extrato etanólico também apresentou melhores resultados em relação à inibição do TNF-α, tendo sido significativa na concentração de 200 μg/mL, frente ao controle positivo (LPS). O extrato hexânico não apresentou inibição da liberação do TNF-α na concentração de 200 μg/mL de forma significativa quando comparada ao LPS. Os resultados deste estudo mostram indícios de atividades anti-inflamatórias nos extratos testados, havendo um melhor desempenho do extrato etanólico. A presença de polifenóis e esteroides/terpenoides encontradas neste extrato podem ser a resposta para uma melhor avaliação das atividades antioxidantes e anti-inflamatórias. Estudos futuros podem indicar um potencial anti-inflamatório promissor para esta planta, lembrando ainda que processos inflamatórios fazem parte do processo de carcinogênese, havendo portanto uma porta de entrada para maiores pesquisas avaliando o potencial anticâncer da C. grandifolia. / In traditional medicine, plants have been used in the treatment of several diseases throughout centuries and are considered as one of the largest sources for the development of new drugs. However, the bioactive components and action mechanisms are not entirely known. Aiming to contribute with scientific knowledge towards the study and development of new drugs, this work sought to identify their main phytochemical components, evaluate their cytotoxic and antioxidant potentials, as well as identifying and evaluating the therapeutic effect of Calyptranthesgrandifolia, through specific and known paths for their involvement in the inflammatory and carcinogenic process, such as TNF- α. Ethanolic and hexanic extracts from C. grandifolialeaves, gathered within the Lajeado municipality, were used in all experiments. The phytochemical analysis of steroids/terpenoids, tannins, flavonoids, coumarins, quinones, alkaloids and saponins were characterized using methodologies described in literature. The in vitro cytotoxic potential was evaluated through the Alamar Blue method using non drug-metabolizing CHOK1 cells and the antioxidant activity was performed through the DPPH method. The analysis of TNF-α release used RAW 264.7 cells, treated with vegetal extracts and posterior stimulation with LPS. The quantification of TNF-α release was quantified using ELISA method. The experiment results indicated the presence of steroids/terpenoids, tannins and flavonoids in the ethanolic extract. The cytotoxic potential did not present considerable cytotoxicity in the ethanolic extract and maintained increased cellular viability in most concentrations, only presenting a slight reduction in viability at 200 μg/mL. Similarly, cellular viability reduction could only be observed in the hexanic extract at the 200 μg/mL concentration. The antioxidant activity was only present in the ethanolic extract at a dose-dependant manner, with an IC50 value of 21.3±1.7μg/mL. The ethanolic extract also presented better results concerning the inhibition of TNF-α, given that it was significant at the 200 μg/mL concentration in comparison with the positive control (LPS). The hexanic extract also presented higher TNF-α inhibition at the 200 μg/mL concentration, however, there was no significant difference in comparison with LPS. The results of this study demonstrate that there are evidences of antiinflammatory activity in the tested extracts, with better performance in the ethanolic extract. The presence of polyphenols and steroids/terpenoids found in this extract may be the answer for its better evaluation concerning antioxidant and anti-inflammatory activities. Future studies may indicate a promising anti-inflammatory potential for this plant, also reminding that inflammatory processes are part of the carcinogenesis process, therefore, this is an entry path for larger researches evaluating the anticarcinogenic potential in C. grandifolia extracts.

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Agradecemos a compreensão. on 2017-05-03T14:13:29Z (GMT) / Submitted by SARAH MARIA BARNEZE COSTA null (sarahbarneze@hotmail.com) on 2017-05-03T16:11:16Z No. of bitstreams: 1 Dissertação Final para o Repositório da Unesp - Aluna Sarah Barneze.pdf: 2656758 bytes, checksum: 41757de66dd6c78c3165310b774a5fcb (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-05-03T16:16:11Z (GMT) No. of bitstreams: 1 costa_smb_me_bot.pdf: 2656758 bytes, checksum: 41757de66dd6c78c3165310b774a5fcb (MD5) / Made available in DSpace on 2017-05-03T16:16:11Z (GMT). No. of bitstreams: 1 costa_smb_me_bot.pdf: 2656758 bytes, checksum: 41757de66dd6c78c3165310b774a5fcb (MD5) Previous issue date: 2017-02-16 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A regulação da remodelação óssea ocorre por meio de fatores locais e sistêmicos. Entre os fatores locais estão as citocinas: Receptor Activator of Nuclear Factor Kappa B Ligand (RANKL), presente nos osteoblastos, e Receptor Activator of Nuclear Factor Kappa B (RANK), presente nos osteoclastos, além de outras citocinas como o Tumor Necrosis Factor Alpha (TNF-α) que podem agir no processo de deposição e/ou reabsorção óssea in vivo. Entre os fatores sistêmicos que participam da remodelação óssea estão os hormônios estrógeno (E2) e triiodotironina (T3). O objetivo do trabalho foi verificar a ação do E2, infrafisiológico (simulando a menopausa) e T3, suprafisiológico (simulando hipertireoidismo) em osteoblastos humanos derivados de células troncos mesenquimais (CTMs) na síntese proteica de RANKL e TNF-α. Os osteoblastos foram incubados por 72 horas na presença de E2 em dose fisiológica (E2F/10-8M) e infrafisiológica (E2I/10-9M), e T3 em dose fisiológica (T3F/10-9M) e suprafisiológica (T3S/10-8M), e quantificada a matriz mineralizada óssea e a síntese proteica de RANKL e TNF-α por Western Blot. A análise estatística dos dados foi realizada pelo teste de variância ANOVA complementada pelo teste de Tukey, sendo o nível de significância considerado p<0,05. O tratamento de E2 em dose E2F (1,96± 0,48; p<0,05) e E2I (3,18±0,31; p<0,001) elevou a síntese proteica de RANKL comparado ao controle (C) (1,00±0,32), e de TNF-α em dose de E2F (3,61±0,45; p<0,05) e E2I (2,45±0,07; p<0,05) também aumentou em relação ao C (1,13±0,19). Assim como o E2, o T3 elevou os níveis proteicos de RANKL em T3F (1,18±0,10; p<0,05) e T3S (1,14±0,004; p<0,05) comparado ao controle (1,00±0,02), porém, TNF-α diminui em dose de T3S (0,82±0,09; p<0,05) relacionado ao T3F (1,00±0,09) e C (0,99±0,04). Com isso, E2I diminuiu a matriz mineralizada óssea e aumentou a síntese de ambas as proteínas estudadas, o que nos leva a especulação de que a reabsorção óssea observada na menopausa seja via RANKL e TNF-α. Por outro lado, na mimetização de hipertireoidismo com o T3S, observamos diminuição da matriz mineralizada óssea, supressão da síntese proteica de TNF-α e aumento de RANKL, o que nos leva a inferir que o mecanismo de reabsorção óssea no hipertireoidismo seja via RANKL. / The regulation of bone remodeling is intermediated by local and systemic factors. The cytokines are among the local factors: Receptor Activator of Nuclear Factor Kappa B Ligand (RANKL), present in osteoblasts, and Receptor Activator of Nuclear Factor Kappa B (RANK), present in osteoclasts, in addition to other cytokines such as Tumor Necrosis Factor Alpha (TNF-α) that can act in the process of bone deposition and/or resorption in vivo. Hormones are among the systemic factors involved in bone remodeling, estrogen (E2) and triiodothyronine (T3). The aim of the study was to verify the action of E2, infraphysiological (simulating menopause) and T3, supraphysiological (simulating hyperthyroidism) in human osteoblasts derived from mesenchymal stem cells (CTMs) in the protein synthesis of RANKL and TNF-α. Osteoblasts were incubated during 72 hours in the presence of E2 at physiological dose (E2F/10 -8 M) and infraphysiological (E2I/10 -9 M), and T3 at physiological (T3F/10 -9 M) and supraphysiological (T3S/10-8 M) and quantified the bone mineralized matrix and the protein synthesis of RANKL and TNF-α by Western Blot. Statistical analysis of the data was performed by the ANOVA variance test complemented by the Tukey test, and the significance level was considered p<0.05. The treatment of E2F in E2F dose (1.96 ± 0.48, p<0.05) and E2I (3.18 ± 0.31; p <0.001) increased RANKL protein synthesis compared to control (C) (1.00 ± 0.32), and TNF-α in the dose of E2F (3.61 ± 0.45; p<0.05) and E2I (2.45 ± 0.07; p <0.05) also increased in relation to C (1.13 ± 0.19). As with E2, T3 increased RANKL protein levels in T3F (1.18 ± 0.10, p <0.05) and T3S (1.14 ± 0.004; p <0.05) compared to control (1 , 00 ± 0.02), but TNF-α decreased in dose T3S (0.82 ± 0.09; p <0.05) related to T3F (1.00 ± 0.09) and C (0, 99 ± 0.04). Thus, E2I decreased the bone mineralized matrix and increased the synthesis of both proteins studied which leads to speculation that bone resorption observed at menopause by RANKL and TNF-α pathway. On the other hand, in the mimicry of hyperthyroidism with T3S, we observed a reduction of the bone mineralized matrix, suppression of TNF-α protein synthesis and increase of RANKL, which leads us to infer that the mechanism of action for bone resorption in hyperthyroidism is by RANKL. / FAPESP: 2014/15529-0