Estudos da fisiologia do estresse são de fundamental importância para a área de endocrinologia comportamental e para projetos visando à promoção do bem estar de animais cativos. Esses estudos, quando feitos com animais de vida-livre, possibilitam investigar quais estímulos ambientais ou sociais são estressores para o táxon estudado. Pouco se sabe a este respeito sobre macacos-prego (gênero Sapajus), um primata neotropical muito comum em zoológicos, criadouros e outras situações de cativeiro. Uma maior compreensão dos agentes estressores neste gênero pode contribuir para o bem estar de sujeitos cativos. Frente a isso, este trabalho objetivou: 1) investigar, a partir da variação dos níveis de glicocorticóides (GCs; hormônios ligados ao estresse), quais eventos ambientais e comportamentais são percebidos por macacos-prego selvagens como estressantes; 2) verificar a possibilidade de definir valores de referência de níveis aceitáveis (nível basal) de metabólitos fecais de glicocorticóides (MFGs a mensuração de GCs a partir de fezes permite avaliar estes hormônios de forma não-invasiva) para o gênero Sapajus; e 3) validar o protocolo experimental de extração e dosagem de hormônios fecais. Em relação aos dois primeiros objetivos, foram tomadas medidas de metabólitos fecais de glicocorticóides, e de dados ambientais e comportamentais de duas populações selvagens, uma do Parque Estadual Carlos Botelho/São Paulo (PECB) e outra da Fazenda Boa Vista/Piauí (FBV). Para a validação do protocolo experimental, foi realizado um desafio de ACTH e dexametasona com macacos-prego cativos. Análises por modelo linear generalizado misto (MLGM) mostraram diferença significativa entre os níveis basais de MFGs das duas populações estudadas, sendo maiores na população da FBV. Para esta população, foi encontrado efeito de oferta de frutos no habitat, de freqüência de encontros com outras espécies animais e de cópulas, sobre a variação mensal dos níveis basais de MFGs. Para a população do PECB, nenhuma das variáveis estudadas apresentou efeito significativo sobre a variação mensal dos níveis basais de MFGs. Já as análises individuais mostraram que interações agonísticas entre membros do grupo foram os maiores causadores de picos de MFGs nos sujeitos estudados, seguidos por fêmeas em período proceptivo e cópulas, que causaram picos não só em machos adultos, mas também em machos juvenis e nas próprias fêmeas. Os resultados do desafio de ACTH e de dexametasona validaram o protocolo experimental de extração e dosagem hormonal. Os resultados obtidos estão de acordo com pesquisas anteriores que revelaram diferenças marcantes no sistema social das duas populações, especialmente no que se refere às relações sociais de fêmeas, de acordo com as diferenças ecológicas entre as duas áreas. Além disso, sugerem que não é possível definir valores de referência de nível basal de MFGs para o gênero Sapajus, já que as duas populações diferem significativamente quanto a este aspecto. A partir deste trabalho, que é apenas o começo de uma longa jornada para a compreensão do estresse em macacos-prego selvagens, começa-se a entender quais são os estressores naturais destes animais e como eles impactam os níveis de MFGs / Stress physiology studies are of fundamental importance for the area of behavioral endocrinology and for projects that aim to promote the wellbeing of captive animals. When the subjects of those researches are wild animals, it is possible to investigate which environmental or social stimuli constitute stressors for this taxon. Little is known in this regard about capuchin monkeys (Sapajus genus), a neotropical primate that are constantly kept in zoos, breeders and others captive environments. A better comprehension of the stressors agents in this genus can contribute for the wellbeing of those captive individuals. Therefore this study aimed: 1) to investigate through the variation of glucocorticoids levels (GCs hormones related to stress), which environmental and behavioral events are perceived by wild capuchin monkeys as stressful; 2) access the possibility of defining basal fecal glucocorticoids metabolites levels (MFGs measuring GCs in feces is a non-invasive form of evaluate those hormones), as reference values, for the Sapajus genus; and 3) validate the experimental protocol of fecal hormones extraction and dosage. For the first two objectives, measures of fecal glucocorticoids metabolites, behavioral and environmental data of two wild populations of capuchin monkeys were taken. One in the Carlos Botelho State Park/São Paulo (PECB) and the other in Boa Vistas Farm/Piauí (FBV). For the experimental protocol validation an ACTH and dexamethasone challenge was executed with captive capuchin monkeys. Generalized Linear Mixed Models (MLGM) analysis showed a significant difference between basal levels of MFGs of the two populations, being the FBV the one with higher values. For that population there was also an effect of fruit availability in the habitat, frequency of encounters with other animals species and copulations in the mensal variation of the MFGs basal levels. There was no significant effect of the studied variables in the mensal basal levels variation of MFGs in the PECB population. The individual analyses showed that agonistic interactions among group members were the major cause of MFGs\' peaks in the studied subjects. Other major factors were females in proceptive period and copulations, that caused peaks not only in adult males, but also in juvenile males and the females themselves. The ACTH and dexamethasone challenge results validated the experimental protocol of hormones extraction and dosage. The obtained results are in agreement with previous researches that reveled marked differences in the social system of the two populations, specially in females social relationships that varied in accordance with the two areas ecological differences. The results also suggested that it is not possible to define reference values of MFGs\' basal levels for the Sapajus genus once the two populations are significantly different in this aspect. This work is just the beginning of a long endeavor to comprehend stress in wild capuchin monkeys, nevertheless it presents the first glimpse to the understanding of the natural stressors for those animals and how they impact the MFGs\' levels

Temos mostrado que os glicocorticóides endógenos (GE) modulam o rolling e a aderência de neutrófilos in vivo, mediando a expressão de moléculas de adesão no leucócito e no endotélio. Adicionalmente, os GE controlam a maturação neutrofílica na medula e a sua mobilização para o sangue periférico. O presente trabalho visou investigar os mecanismos moleculares e celulares envolvidos na modulação exercida pelos GE neste processo. Utilizando ratos Wistar submetidos à adrenalectomia bilateral, tratados com RU 38486 ou controles (falso-operados, tratados com veículo ou não manipulados), foi demonstrado que: 1) os GE controlam, negativamente, a expressão de L-selectina em neutrófilos circulantes e ICAM-1, VCAM-1, PECAM-1, VAP-1 na célula endotelial e, positivamente, a expressão de L-selectina em granulócitos da medula óssea via seu receptor citosólico (GCR); 2) o mecanismo envolvido no controle dos GE sobre a expressão de L-selectina é independente de ação sobre sua expressão gênica ou da atividade de NFkB, mas dependente da expressão de anexina-A1, como verificado em camundongos knockouts (KO) para esta proteína 3) o controle da expressão de moléculas de adesão endotelial é dependente de ações sobre a expressão gênica, via translocação nuclear do NFkB; 4) a neutrofilia detectada em animais adrenalectomizados (ADR) é mediada pelo GCR, e dependente de anexina- A1; 5) a neutrofilia parece ser dependente da ação da anexina-A1 sobre a secreção de SDF-1 na medula óssea e expressão de CXCR-4 em neutrófilos circulantes e da medula; 6) concentrações circulantes elevadas de GE induzidas pela administração de ACTH confirmaram o controle dos GE, via anexina A-1, sobre o tráfego de neutrófilos da medula óssea para o sangue, mas sugerem um controle diferencial dos GE e anexina A-1 sobre a expressão de L-selectina em células da medula e do sangue circulante. Estes dados mostram mecanismos inéditos do controle dos GE sobre o tráfego de neutrófilos, que diferem em cada microambiente e tipo celular envolvido neste complexo fenômeno. / We have shown that endogenous glucocorticoids (GE) modulate the rolling and adhesion of neutrophils in vivo, mediating the expression of adhesion molecules on leukocytes and the endothelium. Additionally, the GE control neutrophil maturation in bone marrow and mobilization to peripheral blood. This work aimed to investigate the molecular and cellular mechanisms involved in the modulation exerted by GE in this process. Using male Wistar rats, submitted to bilateral adrenalectomy, treatment with RU 38 486 or controls (sham operated, vehicle or non manipulated), it was shown that: 1) GE control, negatively, L-selectin expression on circulating neutrophils and ICAM-1, VCAM-1, PECAM-1, VAP-1 on endothelial cell and, positively, L-selectin expression on bone marrow granulocytes via their cytosolic receptor (GCR); 2) the mechanism involved in the control of GE on the L-selectin expression is independent of its action on gene expression or NFkB activity, but dependent on the expression of anexina-A1, as observed in mice knockouts for this protein; 3) the control of endothelial adhesion molecules is dependent on gene expression, via NFkB translocation; 4) the neutrophilia detected in adrenalectomized animals (ADR) is mediated by GCR, and dependent on anexina-A1; 5) the neutrophilia seems to be dependent on the action of annexin A-1 on SDF-1α secretion in bone marrow and expression of CXCR-4 in peripheral blood and bone marrow; 6) high circulating concentrations of GE induced by administration of ACTH confirmed the control of GE, via the annexin-1, on the traffic of neutrophils from the bone marrow to the blood, but suggest a differential control of GE and annexin A-1 on the L-selectin expression in the bone marrow and circulating blood. These data indicate unpublished mechanisms of control of GE on the traffic of neutrophils, which differ in each microenvironment and cell type involved in this complex phenomenon.

Glucocorticoids, key hormonal regulators of the stress response, powerfully influence inflammation and metabolism. Reducing excessive glucocorticoid exposure is beneficial in treating metabolic and cognitive disorders, but manipulating systemic endogenous glucocorticoids risks compromising their beneficial effects. The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activates glucocorticoids in target tissues and thus inhibition of this enzyme presents a clinical opportunity to reduce tissue-specific glucocorticoid action. Active glucocorticoids also exert potent angiostatic effects by binding the glucocorticoid receptor (GR), and 11β-HSD1 inhibitors have proven beneficial in models of myocardial infarction by promoting angiogenesis. The possibility that 11β-HSD1 inhibitors may increase pathological angiogenesis, such as that seen in solid tumours, remains unaddressed. This project tested the hypothesis that 11β-HSD1 inhibition promotes tumour growth as a result of increased angiogenesis, using murine models of squamous cell carcinoma (SCC) and pancreatic ductal adenocarcinoma (PDAC). Murine SCC or PDAC cells were injected (1x106 cells/flank) into WT female mice fed either standard diet, or diet containing the 11β-HSD1 inhibitor UE2316 (175 mg/kg, N=6/group), or into 11β-HSD1 knockout (Del1) mice fed standard diet. Developing tumours were measured by callipers over several weeks, before animals were culled and tissues collected. SCC tumours grew more rapidly in UE2316-treated mice to reach a significantly (P < 0.01) larger final volume (0.158 ± 0.037 cm3) than in control mice (0.051 ± 0.007 cm3). PDA tumours were unaffected by 11β-HSD1 inhibition or deletion. Immunofluorescent co-staining of tumour sections for CD31/α-smooth muscle actin revealed no differences in vessel density, and RT-qPCR showed no difference in angiogenic factor expression, after 11β-HSD1 inhibition/deletion in either tumour type. GR and 11β-HSD1 RNA expression were greater in SCC vs PDAC tumours (P < 0.001), as was 11β-HSD1 activity (P < 0.0001). In studies using the aortic ring assay of ex vivo angiogenesis, 11β-HSD1 deletion, but not inhibition with UE2316, was shown to prevent glucocorticoid-mediated angiostasis. The growth/viability of tumour cell lines was not affected by UE2316 or corticosterone, as assessed by live cell imaging using the Incucyte imaging system. RNA-sequencing of SCC tumours revealed that multiple factors involved in the innate immune/inflammatory response were reduced in UE2316-treated tumours, and that extracellular matrix regulation was also altered by UE2316. Imaging of tumour sections using Second Harmonic Generation microscopy confirmed that UE2316 altered Type I collagen deposition in SCC (P < 0.001) but not PDAC. 11β-HSD1 inhibition can increase tumour growth, possibly via suppression of inflammatory/immune cell signalling and alteration of the extracellular matrix, and tumours with higher GR and 11β-HSD1 content, such as SCC, may be more at risk. Interestingly this investigation found no evidence of increased angiogenesis in vivo or ex vivo after UE2316 treatment, suggesting that 11β-HSD1 inhibition does not promote angiogenesis in all ischaemic environments. Future work must focus on the effects of 11β-HSD1 inhibition on the immune and extracellular matrix component of the tumour microenvironment. While promotion of pathological angiogenesis does not appear to pose a major threat, 11β-HSD1 inhibitors may still interact with the immune and inflammatory environment in tumours to the detriment of health.

Estudos da fisiologia do estresse são de fundamental importância para a área de endocrinologia comportamental e para projetos visando à promoção do bem estar de animais cativos. Esses estudos, quando feitos com animais de vida-livre, possibilitam investigar quais estímulos ambientais ou sociais são estressores para o táxon estudado. Pouco se sabe a este respeito sobre macacos-prego (gênero Sapajus), um primata neotropical muito comum em zoológicos, criadouros e outras situações de cativeiro. Uma maior compreensão dos agentes estressores neste gênero pode contribuir para o bem estar de sujeitos cativos. Frente a isso, este trabalho objetivou: 1) investigar, a partir da variação dos níveis de glicocorticóides (GCs; hormônios ligados ao estresse), quais eventos ambientais e comportamentais são percebidos por macacos-prego selvagens como estressantes; 2) verificar a possibilidade de definir valores de referência de níveis aceitáveis (nível basal) de metabólitos fecais de glicocorticóides (MFGs a mensuração de GCs a partir de fezes permite avaliar estes hormônios de forma não-invasiva) para o gênero Sapajus; e 3) validar o protocolo experimental de extração e dosagem de hormônios fecais. Em relação aos dois primeiros objetivos, foram tomadas medidas de metabólitos fecais de glicocorticóides, e de dados ambientais e comportamentais de duas populações selvagens, uma do Parque Estadual Carlos Botelho/São Paulo (PECB) e outra da Fazenda Boa Vista/Piauí (FBV). Para a validação do protocolo experimental, foi realizado um desafio de ACTH e dexametasona com macacos-prego cativos. Análises por modelo linear generalizado misto (MLGM) mostraram diferença significativa entre os níveis basais de MFGs das duas populações estudadas, sendo maiores na população da FBV. Para esta população, foi encontrado efeito de oferta de frutos no habitat, de freqüência de encontros com outras espécies animais e de cópulas, sobre a variação mensal dos níveis basais de MFGs. Para a população do PECB, nenhuma das variáveis estudadas apresentou efeito significativo sobre a variação mensal dos níveis basais de MFGs. Já as análises individuais mostraram que interações agonísticas entre membros do grupo foram os maiores causadores de picos de MFGs nos sujeitos estudados, seguidos por fêmeas em período proceptivo e cópulas, que causaram picos não só em machos adultos, mas também em machos juvenis e nas próprias fêmeas. Os resultados do desafio de ACTH e de dexametasona validaram o protocolo experimental de extração e dosagem hormonal. Os resultados obtidos estão de acordo com pesquisas anteriores que revelaram diferenças marcantes no sistema social das duas populações, especialmente no que se refere às relações sociais de fêmeas, de acordo com as diferenças ecológicas entre as duas áreas. Além disso, sugerem que não é possível definir valores de referência de nível basal de MFGs para o gênero Sapajus, já que as duas populações diferem significativamente quanto a este aspecto. A partir deste trabalho, que é apenas o começo de uma longa jornada para a compreensão do estresse em macacos-prego selvagens, começa-se a entender quais são os estressores naturais destes animais e como eles impactam os níveis de MFGs / Stress physiology studies are of fundamental importance for the area of behavioral endocrinology and for projects that aim to promote the wellbeing of captive animals. When the subjects of those researches are wild animals, it is possible to investigate which environmental or social stimuli constitute stressors for this taxon. Little is known in this regard about capuchin monkeys (Sapajus genus), a neotropical primate that are constantly kept in zoos, breeders and others captive environments. A better comprehension of the stressors agents in this genus can contribute for the wellbeing of those captive individuals. Therefore this study aimed: 1) to investigate through the variation of glucocorticoids levels (GCs hormones related to stress), which environmental and behavioral events are perceived by wild capuchin monkeys as stressful; 2) access the possibility of defining basal fecal glucocorticoids metabolites levels (MFGs measuring GCs in feces is a non-invasive form of evaluate those hormones), as reference values, for the Sapajus genus; and 3) validate the experimental protocol of fecal hormones extraction and dosage. For the first two objectives, measures of fecal glucocorticoids metabolites, behavioral and environmental data of two wild populations of capuchin monkeys were taken. One in the Carlos Botelho State Park/São Paulo (PECB) and the other in Boa Vistas Farm/Piauí (FBV). For the experimental protocol validation an ACTH and dexamethasone challenge was executed with captive capuchin monkeys. Generalized Linear Mixed Models (MLGM) analysis showed a significant difference between basal levels of MFGs of the two populations, being the FBV the one with higher values. For that population there was also an effect of fruit availability in the habitat, frequency of encounters with other animals species and copulations in the mensal variation of the MFGs basal levels. There was no significant effect of the studied variables in the mensal basal levels variation of MFGs in the PECB population. The individual analyses showed that agonistic interactions among group members were the major cause of MFGs\' peaks in the studied subjects. Other major factors were females in proceptive period and copulations, that caused peaks not only in adult males, but also in juvenile males and the females themselves. The ACTH and dexamethasone challenge results validated the experimental protocol of hormones extraction and dosage. The obtained results are in agreement with previous researches that reveled marked differences in the social system of the two populations, specially in females social relationships that varied in accordance with the two areas ecological differences. The results also suggested that it is not possible to define reference values of MFGs\' basal levels for the Sapajus genus once the two populations are significantly different in this aspect. This work is just the beginning of a long endeavor to comprehend stress in wild capuchin monkeys, nevertheless it presents the first glimpse to the understanding of the natural stressors for those animals and how they impact the MFGs\' levels

A neuroimunomodulação é um ramo da ciência que estuda as inter-relações existentes entre o SNC e o SI. O termo inter-relações foi empregado porque, sabe-se hoje serem estas relações bidirecionais. Conhecendo-se a existência desta comunicação, não é difícil de se supor que substâncias que atuem no sistema neuro-endócrino tenham a capacidade de influenciar as respostas imunes seja por uma ação neuroimune indireta ou por outra que se faça diretamente nas células imunes. Os canabinóides (endógenos, derivados da planta e sintéticos) apresentam um amplo espectro de ações, dentre as quais cabe destacar aquelas sobre o comportamento (ansiedade e medo), o sistema neuro-endócrino (ativação do eixo HHA) e imune (resposta imune inata e adquirida). Estes efeitos são geralmente atribuídos à ligação dos canabinóides a receptores específicos presentes no SNC (receptores CB1) e na periferia (receptores CB2). Neste sentido, buscamos neste trabalho avaliar os efeitos da Anandamida (AEA), uma agonista canabinóide endógeno, sobre o comportamento, a ativação do eixo HHA e alguns parâmetros de atividade imune adquirida, e o fizemos à luz de mecanismos neuroimunomodulatórios. Nossos resultados mostraram que os efeitos da AEA sobre o comportamento são dependentes da dose e, também, do tempo de latência para as observações. Neste sentido, 10 minutos após a administração de doses crescentes de AEA observou-se, tanto no campo aberto como no LCE, um efeito que seguiu um padrão de curva em U invertido dependente da dose. Nossos resultados mostraram, também, que a AEA na dose de 0,1mg/kg administrada 90 minutos antes das observações, aumentou o tempo gasto pelos animais em movimento na zona periférica e diminui o tempo gasto em movimento na zona central do campo aberto. Mostrou-se, ainda, que a AEA na dose de 0,1mg/kg aumentou acentuadamente os níveis séricos de corticosterona nos animais medidos 45 e 90 minutos após a administração. Finalmente, mostrou-se que uma dose de 0,1mg/kg de AEA previamente a uma imunização com OVA promoveu um aumento da reposta de hipersensibilidade do tipo tardia (DTH) e um aumento na porcentagem de proliferação de células T CD4+. Estes resultados em seu conjunto permitem sugerir que a AEA (0,1mg/kg) administrada 90 minutos antes das observações tenha se comportado como um estressor químico, promovendo efeito semelhante ao de ansiogênicos no campo aberto e aumentando os níveis séricos de corticosterona; esses níveis aumentados de corticosterona teriam sido os responsáveis pelo aumento da resposta imune celular (Th1) observada. / Neuroimmunomodulation is a field of research concerned with the relationships between the CNS and the IS. The term relationship is frequently employed because it is assumed that such communication is bidirectional. In this regard, if we consider that this communication exists, it should be accetable that substances acting on the neuroendocrine system are able of modifying immune responses, either acting via a neuroimmune indirect pathway, or acting directly on immune cells. Cannabinoids (endogenous, plant derived, and synthetic) show a large spectrum of actions over the body. We emphasize here, behavioral (anxiety and fear), endocrine (HPA axis activation), and immune (innate and adaptative immunity) effects. These effects are generally attributed to cannabinoid bind to specific receptors present on CNS (CB1 receptors) and in the periphery (CB2 receptors). In this sense, we evaluated Anandamide (AEA, an endogenous cannabinoid agonist) effects, on behavior, HPA axis activation, and parameters of adaptative immunity, particularly neuroimmune relationships. Briefly, our results show that the AEA effects on behavior are dependent on the dose and time. Thus, 10 minutes after injection of growing increasing doses of AEA, we found in the open field and plus maze an inverted U-shape dose-response for AEA which is characteristic of cannabinoids in this type of behavioral evaluation. Additionally we show, that AEA 0,1mg/kg after 90 minutes of administration increased the time spent in the peripheral zone, and decreased the time spent in the central zone of the open field. Furthermore, we found that AEA 0.1mg/kg strongly increased the serum levels of corticosterone after 45 and 90 minutes of administration. Finally, we show that AEA 0.1mg/kg prior to immunization promoted an increase of delayed-type hypersensitivity (DTH) and an increase in the percentage of CD4+ T cell proliferation. These results allow us to suggest that AEA 0.1mg/kg 90 minutes after administration acted as a chemical stressor, promoting an anxiogenic-like effect in the open field, and increasing the serum levels of corticosterone. Additionally, the increased levels of corticosterone at the moment of antigenic exposition could be responsible for the increased cell-mediated immunity (Th1) observed.

No description available.

Orientador: Valdir Gouveia Garcia / Banca: Maria José Hitomi Nagata / Banca: Álvaro Francisco Bosco / Banca: Ariel Lenharo / Banca: Jamil Awad Shibli / Resumo: As modalidades terapêuticas que envolvem implantes dentais têm se expandido gradativamente, sendo implantados em uma variedade de estruturas ósseas. Dessa forma, o propósito do presente trabalho foi estudar a influência de corticóides no processo inicial de osseointegração de implantes de titânio instalados em maxilas de ratos. Foram utilizados implantes de titânio c.p., grau II, cônico de 1,4mm de diâmetro e 2,7mm de comprimento, com superfície tratada. Trinta e oito ratos wistar tiveram seus primeiros molares superiores esquerdo e direito extraídos. Após 30 dias de reparo alveolar, dois animais foram sacrificados para confirmar o fim desse processo. Os demais animais tiveram os implantes instalados bilateralmente e foram divididos randomicamente em três grupos: Controle (Ctr/n=12) que não receberam nenhum tipo de tratamento; Placebo (Pl/n=12) e Tratado (Tra/n=12), que receberam injeções diárias de 1 ml de solução salina e corticosterona na dosagem de 5mg/kg, respectivamente. Trinta dias após a implantação, todos os animais foram eutanasiados e tiveram a concentração plasmática do corticóide mensurada: Ctr (101,31 ± 26,7 ng/ml), Pla (95,22 ± 25,36 ng/ml) e Tra (281,37 ± 64,72 ng/ml); e o contato osso-implante determinado: Ctr (96,67%), Pla (82,22%) e Tra (15,73%), nos quais o grupo Tra apresentou-se estatisticamente diferente dos demais grupos (p<0,05). Assim, diante da metodologia empregada, foram evidenciadas menor formação óssea e conseqüente redução da área de tecido ósseo neo-formado na interface osso-implante. / Abstract: The therapeutic modalities which involves dental implants has been gradually expanded, being implanted in a variety of bone structures. In this way, the aim of the present work was to study the corticoid influence at the initial process of bone integration of titanium implants installed in rat jaws. It were used titanium implants c.p.; grade II, conic with 1,4mm diameter and 2,7mm length, with treated surface. Thirty eight wistar rats had their first upper left and right molars extracted. After 30 days of alveolar repair, two animals were sacrificed to confirm the end of this process. The others had their implants installed bilaterally and they were splited randomly in three groups: Control (Ctr/n=12) which did not receive any kind of treatment; Placebo (Pla/n=12) and Treated (Tre/n=12) which received 1ml daily shots of salt solution and corticosterone at a dosage of 5mg/Kg, respectively. Thirty days after the implantation, all the animals were euthanasiated and the plasmatic concentration of corticoid was measured: Ctr (101,31 ± 26,7 ng/ml), Pla (95,22 ± 25,36 ng/ml) and Tre (281,37 ± 64,72 ng/ml); and the bone implant contact was determined: Ctr (96,67%), Pla (82,22%) and Tre (15,73%), in which the Tre group presented statistically different from the other groups (p<0,05). Thus, front the employed methodology it was shown lesser bone formation and consequent reduction of the bone tissue area neo-formed at bone-implant interface. / Doutor

Orientador: João Carlos Pinheiro Ferreira / Banca: Eunice Oba / Banca: Ian Martin / Resumo: As aves da família Psittacidae são muito visadas pelo tráfico de animais selvagens. O papagaio-verdadeiro (Amazona aestiva) é uma das espécies mais traficadas. Os animais provenientes do tráfico são transportados em espaço restrito, sem alimento ou água e as aves adoecem ou morrem devido ao estresse ou brigas, antes mesmo de chegarem ao consumidor final. O estresse leva a secreção de glicocorticoides que possui diversas funções nos vertebrados além de sofrerem flutuações dos seus níveis basais para preparar o organismo para o início das atividades diárias. Fatores ambientais e necessidades fisiológicas interagem para a manutenção do relógio biológico, que é responsável por determinar essas alterações endócrinas. As análises hormonais através de técnicas não-invasivas têm sido usadas em estudos da biologia da conservação, comportamentais e fisiológicos em aves cativas ou de vida livre devido a sua facilidade de coleta e por não causarem prejuízos ao indivíduo. Os níveis de metabólitos de glicocorticoides presentes nas excretas refletem as concentrações plasmáticas desses hormônios. Com objetivo de determinar o perfil de excreção urofecal de metabólitos de glicocorticoides nos excrementos de A. aestiva, ao longo do dia e relacionar esses achados com as atividades diária desses animais, foram utilizados 22 animais (12 machos e 10 fêmeas) alojados em gaiolas individuais, e suas excretas foram colhidas a cada três horas, por 24 horas consecutivas. Foi observado um pico nas concentrações de metabólitos de glicocorticóides nas primeiras horas do dia, quando também se inicia as atividades diárias das aves; e as concentrações diminuíram gradualmente até atingirem seus níveis basais no final da tarde e se mantiveram baixos até a manhã seguinte / Abstract: The birds of the Psittacidae family are highly targeted for wildlife trafficking. The Blue-fronted parrot (Amazona aestiva) is one of the most trafficked species. The animals are transported in restricted spaces, without food or water and the birds get sick or die due to stress or fights, before arriving to the final consumer. Stress leads to secretion of glucocorticoids that has several functions in vertebrates and suffer fluctuations of baseline levels to prepare the organism for the start of daily activities. Physiological and environmental factors interact to maintain the biological clock, which is responsible for determining these endocrine changes. The hormonal assays employing non-invasive techniques have been used in studies of conservation biology, behavioral and physiological studies of captive or free-living birds because of the ease of collection and lack of harm to the individual. Levels of glucocorticoid metabolites in feces reflect plasma concentrations of these hormones. In order to define the profile of excretion of glucocorticoids metabolites in A. aestiva droppings throughout the day and correlate these findings with the daily activities of these animals, we used 22 animals (12 males and 10 females) housed individually in cages, and their droppings were collected every three hours for 24 consecutive hours. A peak in the concentration of glucocorticoids metabolites was observed in the first hours of the day at the start of the birds' daily activities, and the concentrations decreased gradually to basal levels in the late afternoon and remained low until the next morning / Mestre

Insulin plays a vital role in whole-body metabolism and provides a major anabolic stimulus for cellular signaling pathways, including those involved in the metabolism of glucose and protein. Consequently, insulin dysregulation (ID) is known to alter molecular signal transduction in insulin-sensitive tissues such as skeletal muscle, thereby disrupting glucose metabolism and compromising protein synthetic capacity. Our first objective was to induce ID in healthy horses by administering dexamethasone (DEX), a potent glucocorticoid, for 21 days. We evaluated the effects on insulin-stimulated muscle protein signaling components involved in the mammalian target of rapamycin (mTOR) pathway. DEX-induced ID reduced insulin-stimulated activation of downstream (rpS6, 4EBP-1) mTOR signaling and increased atrogin-1 abundance, a marker for protein breakdown (P < 0.05). Additionally, 21 days of DEX elevated plasma amino acids levels in insulin-stimulated conditions, indicative of reduced uptake or increase release into circulation (P < 0.05). The second objective was to evaluate the short-term effects of DEX treatment in healthy horses. Plasma insulin, glucose and amino acid dynamics and activation of mTOR signaling pathways following an oral sugar test (OST) or intake of a high protein meal were evaluated before and after 7 days of DEX treatment, and after 7 days of no treatment. Seven days of DEX treatment increased basal levels of glucose, insulin and several amino acids (P < 0.05). Additionally horses treated with DEX had an exacerbated insulin response to the OST and consumption of the high protein meal in comparison to control horses (P < 0.05). The majority of blood metabolites returned to basal levels after 7 days of recovery from DEX treatment, indicating these effects were transient. Short-term DEX treatment decreased overall activation of mTOR and FoxO3 but increased total FoxO3 and IRS-1 abundance (P < 0.05). Postprandial activation of rpS6 was greater in horses treated with DEX for 7 days but was lower in those horses after 7 days of recovery from treatment (P < 0.05). Postprandial activation of ULK and AMPK tended to be greater in DEX treated horses (P < 0.1). Akt phosphorylation and mysotatin abundance were lower after the OST in DEX treated horses (P < 0.05). The final objective was to evaluate whether similar changes in postprandial metabolic responses would be seen in horses with naturally occurring ID. Plasma insulin, glucose and amino acid responses following ingestion of a high protein meal were determined in mature horses with equine metabolic syndrome (EMS). Horses with EMS had higher basal plasma insulin concentrations but lower levels of aspartate, glutamate, asparagine and plasma urea nitrogen in comparison to healthy controls (P < 0.05). Consumption of a high protein meal resulted in a 9-fold greater insulin response and higher postprandial levels of various amino acids (P < 0.05). Together this research indicates that ID affects whole body protein metabolism by altering cellular signaling pathways in healthy and diseased horses.

A devastating feature of drug-dependence is the susceptibility of relapse (40-60%) after stretches of abstinence. One theory that may account for relapse suggests that drug cues (e.g., paraphernalia) may increase stress hormones, and this may prompt relapse. Repeatedly pairing a neutral cue with a reward is commonly utilized to measure what subjects learn about a cue that is predictive of reward. Research has shown that animals that attend to a cue more than to the reward (sign trackers) may be more vulnerable to drug addiction. Additionally, research has shown that sign tracking is associated with an increase in corticosterone (CORT), a primary stress hormone. PT 150 is a novel glucocorticoid receptor antagonist that attenuates the effects of CORT. Experiment 1 hypothesized that subjects given repeated oral administration of 40 mg/kg PT 150 would reduce sign tracking compared to subjects given placebo. Results of Experiment 1 showed that repeated oral consumption of 40 mg/kg PT 150 decreased sign tracking behavior compared to placebo. In Experiment 2, it was hypothesized that PT 150 (20/40/60 mg/kg) given by subcutaneous (SC) injection would reduce sign tracking dose-dependently, and that sign tracking behavior would correlate with CORT levels. Results of Experiment 2 showed that SC injection of 20 mg/kg PT 150 reduced sign tracking but not 40 or 60 mg/kg. Additionally, the correlation between CORT and the sign tracking for the 20 mg/kg approached significance. Although tentative, the correlation may suggest that elevated plasma CORT concentrations correlate with elevated sign tracking. The current findings extend the current literature by suggesting that the glucocorticoid receptor may be a potential pharmacological target for reducing relapse-like behaviors.