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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The effect of MPTP treatment on the catecholamine content of the adrenal medulla in unilaterally adrenalectomized mice

Cook, Jennifer A. January 1993 (has links)
This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).
22

"Diagnóstico e tratamento das massas adrenais clinicamente silenciosas: revisão de literatura" / Diagnostic and therapeutic approach in adrenal masses clinically silent: review of the literature

Sette, Marcelo José 02 September 2005 (has links)
Massas adrenais clinicamente silenciosas, diagnosticadas ao acaso ("incidentalomas"), são frequentemente encontradas em avaliações radiológicas devido ao constante progresso dos métodos de imagem. Na revisão das principais fontes científicas até 2004, analisado o grau de evidência concluiu-se: a maioria dos "incidentalomas" são não hipersecretores, mas a avaliação endócrina demonstrou que é comum o achado de hiperfunção hormonal discreto; "incidentaloma" acima de 6cm sugerem malignidade e entre 4-6cm devem ser analisadas por suas características de imagem; adrenalectomia deve ser indicada em massas adrenais funcionantes; massas adrenais não operadas devem ser acompanhadas pelo prazo de 2 anos / Introduction: Clinically silent adrenal masses, incidentally diagnosed during imaging methods performed for other clinical conditions (“incidentalomas") have been more frequently detected due to the constant improvement in imaging methods. There are several causes, diagnoses and treatments for these masses. Thus, whenever a physician comes across such lesion, it is necessary to define whether this mass is hormonally active and whether there is a risk of being malignant. Nevertheless, the methods for clarifying these issues have yet to be defined. Objective: To evaluate the best diagnosis, treatment and follow up of the incidental adrenal lesion. Methods: The main scientific literature available until October 2004 was reviewed, taking evidence into account. Results: Two studies which selected and reviewed articles until September 2003 were found. Fourty-three other studies included in a systematic review until October 2004 were added to this study. Conclusions: In general, “incidentalomas" are non-functioning, but endocrinological evaluation has shown that subclinical hormonal hyperfunction is not unusual, thus stressing the need for measuring substances such as with metanephrine assay, dexamethasone suppression test in low dosage and establishing the upright plasma aldosterone/plasma renin activity ratio. Non-functioning “incidentalomas" smaller than 4 cm should be followed carefully; those between 4 and 6 cm should be analyzed for its imaging characteristics; for those greater than 6 cm adrenalectomy is indicated. Functioning “incidentalomas" must undergo adrenalectomy. Nonoperated adrenal masses must be followed for two years through imaging and function testing.
23

Adrenalectomy-induced neuronal degeneration : development of a novel animal model of cognitive dysfuntion and neurogenic treatment strategies

Spanswick, Simon, University of Lethbridge. Faculty of Arts and Science January 2010 (has links)
Long-term adrenalectomy (ADX) results in a specific loss of dentate gyrus granule cells in the hippocampus of adult rats, occurring over a period of weeks to months. This loss of granule cells results in cognitive deficits in a number of tasks that depend on intact hippocampal function. The gradual nature of ADX-induced cell death and the ensuing deficits in cognition are similar to those experienced by patient populations suffering from a variety of pathological conditions. Here we present an animal model by which we use ADX to produce a loss of granule cells within the hippocampus of rats. We also provide experimental evidence for a treatment strategy by which the lost granule cells may be replaced, with the goal of functional recovery in mind. / xii, 191 leaves : ill. (chiefly col.) ; 28 cm
24

Experienced-induced immediate early gene expression in hippocampus after granule cell loss

Cardiff, James W January 2012 (has links)
Adrenalectomy (ADX) has been shown to cause selective degeneration of granule cells in the dentate gyrus (DG). This occurs due to the reduction of corticosterone (CORT) and behavioural deficits are associated with the loss of these neurons. Dentate lesions and cell loss associated with ADX have been shown to effect behaviour in a number of spatial tasks. In contras, it has been shown granule cell loss does not affect the specificity of place cells in CA3 and CA1. We used the ADX model to examine the role of DG granule cells plays in representing space using immediate early gene (IEG) activation in the principal hippocampal subfields after exploration of novel environments. Rats were allowed to free explore multiple novel environments and then the mRNA for the IEG Homer 1a (H1a) was used as a marker of neural activity. After degeneration of approximately half of the DG granule cells we found a significant increase in number of active cells in the DG, CA3 and CA1 in ADX animals. The results indicate a reduction in granule cells causes a dramatic increase in the proportion of remaining DG granule cells in response to exploration. The change in DG activation disrupts the representations in CA3 and CA1 and thereby affects behaviour. / vii, 60 leaves : ill. (some col.) ; 29 cm
25

"Diagnóstico e tratamento das massas adrenais clinicamente silenciosas: revisão de literatura" / Diagnostic and therapeutic approach in adrenal masses clinically silent: review of the literature

Marcelo José Sette 02 September 2005 (has links)
Massas adrenais clinicamente silenciosas, diagnosticadas ao acaso ("incidentalomas"), são frequentemente encontradas em avaliações radiológicas devido ao constante progresso dos métodos de imagem. Na revisão das principais fontes científicas até 2004, analisado o grau de evidência concluiu-se: a maioria dos "incidentalomas" são não hipersecretores, mas a avaliação endócrina demonstrou que é comum o achado de hiperfunção hormonal discreto; "incidentaloma" acima de 6cm sugerem malignidade e entre 4-6cm devem ser analisadas por suas características de imagem; adrenalectomia deve ser indicada em massas adrenais funcionantes; massas adrenais não operadas devem ser acompanhadas pelo prazo de 2 anos / Introduction: Clinically silent adrenal masses, incidentally diagnosed during imaging methods performed for other clinical conditions (“incidentalomas”) have been more frequently detected due to the constant improvement in imaging methods. There are several causes, diagnoses and treatments for these masses. Thus, whenever a physician comes across such lesion, it is necessary to define whether this mass is hormonally active and whether there is a risk of being malignant. Nevertheless, the methods for clarifying these issues have yet to be defined. Objective: To evaluate the best diagnosis, treatment and follow up of the incidental adrenal lesion. Methods: The main scientific literature available until October 2004 was reviewed, taking evidence into account. Results: Two studies which selected and reviewed articles until September 2003 were found. Fourty-three other studies included in a systematic review until October 2004 were added to this study. Conclusions: In general, “incidentalomas” are non-functioning, but endocrinological evaluation has shown that subclinical hormonal hyperfunction is not unusual, thus stressing the need for measuring substances such as with metanephrine assay, dexamethasone suppression test in low dosage and establishing the upright plasma aldosterone/plasma renin activity ratio. Non-functioning “incidentalomas” smaller than 4 cm should be followed carefully; those between 4 and 6 cm should be analyzed for its imaging characteristics; for those greater than 6 cm adrenalectomy is indicated. Functioning “incidentalomas” must undergo adrenalectomy. Nonoperated adrenal masses must be followed for two years through imaging and function testing.
26

ETHANOL REGULATION OF GLUCOCORTICOID RESPONSIVE GENES

Costin, Blair 18 April 2013 (has links)
Glucocorticoid hormones modulate acute and chronic behavioral and molecular responses to drugs of abuse including psychostimulants and opioids. Acute ethanol activates the hypothalamic pituitary adrenal (HPA) axis causing the release of adrenal glucocorticoid hormones, but following chronic ethanol the HPA axis is dysregulated in both humans and rodents. Thus, there is growing evidence that glucocorticoids might also modulate behavioral and molecular responses to ethanol. Previous microarray studies in the Miles’ laboratory have shown that the well-known glucocorticoid responsive gene, Serum and Glucocorticoid-regulated Kinase 1, Sgk1, is prominently up regulated by acute ethanol (2 g/kg) in the prefrontal cortex (PFC) of DBA/2J mice. Functionally, Sgk1 is an important focal point of intracellular signaling cross-talk through which the cell surface receptors, nuclear receptors, and cellular stress pathways converge to control many cellular processes including receptor or ion channel trafficking, cell proliferation and/or apoptotic responses. In the aforementioned microarray studies, Sgk1 was accompanied by a highly correlated group of genes, many of which are also known to respond to glucocorticoids. This suggests that stress-related signaling events might play an important role in ethanol regulation of the Sgk1 gene network. Prior work by others showed that Sgk1 plays an important role modulating synaptic plasticity occurring in memory. Based on these findings, it is hypothesized that glucocorticoids and glucocorticoid responsive genes are responsible for modulating acute and chronic cellular and behavioral responses to ethanol including locomotor activation and ethanol sensitization. In particular, because Sgk1 is regulated by ethanol, has a well-established role in learning and memory and is responsive to glucocorticoid signaling we hypothesize that Sgk1 is involved in modulating acute and chronic cellular and behavioral responses to ethanol including ethanol sensitization. Our results indicate that the induction of glucocorticoid responsive genes may play a role in regulating acute behavioral and cellular responses to ethanol. Adrenalectomized (ADX) and mifepristone (RU-486) both impaired acute ethanol (2 g/kg) induced locomotor activation in DBA/2J mice without affecting basal locomotor activity. ADX mice showed microarray gene expression changes in the PFC that significantly overlapped with acute ethanol-responsive gene sets derived by our prior microarray studies. Additionally, acute ethanol regulates Sgk1 transcription via glucocorticoid receptor binding to the Sgk1 promoter. Furthermore, increases in Sgk1 may occur to compensate for decreases in SGK1 protein and phosphorylation of SGK1 and its well-known target N-myc downstream-regulated gene 1 (NDRG1) is significantly increased 15 minutes following ethanol administration. Finally, Sgk1 intensifies and prolongs the expression phase of sensitization in D2 mice. Our studies suggest that ethanol’s activation of adrenal glucocorticoid release and subsequent glucocorticoid receptor activation may partially modulate ethanol’s acute locomotor activation in male D2 mice. Furthermore, adrenal glucocorticoid basal tone regulates PFC gene expression. A significant set of acute ethanol-responsive genes are regulated by adrenal glucocorticoid basal tone suggesting that glucocorticoid regulated PFC gene expression may be an important factor modulating acute behavioral responses to ethanol. Sgk1 is acutely regulated following ethanol administration by the glucocorticoid receptor binding to the Sgk1 promoter. Altogether, these results suggest a critical role for the hypothalamic pituitary adrenal axis and Sgk1 in regulating the acute and chronic cellular and behavioral responses to ethanol.
27

Participação do eixo hipotálamo-pituitária-adrenal na Doença Inflamatória Intestinal induzida experimentalmente / Participation of the hypothalamic-pituitary-adrenal axis in experimentally induced inflammatory bowel disease

Souza, Patrícia Reis de 06 August 2015 (has links)
As doenças inflamatórias intestinais (DII) são causadas por desequilíbrio entre as respostas imunes efetoras e reguladoras na mucosa intestinal e podem ser moduladas pelo eixo hipotálamo-hipófise-adrenal (HPA) por meio de interações neuroimunoendócrinas e secreção de cortisol. Embora os glicocorticóides (GC) sejam utilizados para tratar a DII, o cortisol produzido pelas glândulas supra-renais também está envolvido na resposta ao estresse, que pode levar a doenças inflamatórias descontroladas. Portanto, o objetivo deste trabalho é avaliar a participação do eixo HPA na modulação da resposta imune de mucosa intestinal. Para tal, camundongos C57BL/6 foram submetidos à remoção das glândulas adrenais seguida por indução de colite pela administração de água contendo 3% de dextran sulfato de sódio (DSS). Os resultados demonstraram que a ausência das adrenais levou à maior suscetibilidade à doença e mortalidade precoce, fenômeno que não foi prevenido pela reposição de GC. Os animais adrenalectomizados com colite apresentaram níveis significativamente menores de LPS, concomitantemente ao aumento de IL-6 no soro quando comparados aos camundongos não adrenalectomizados. Além disso, os animais adrenalectomizados apresentaram menor celularidade na lâmina própria (LP), menos áreas de erosão e menor escore histopatológico associado ao aumento de IFN-? e FasL, no intestino, sem produção local compensatória de corticosterona. Houve aumento na atividade das enzimas mieloperoxidase (MPO), N- acetilglicosaminidase (NAG) e eosinófilo-peroxidase (EPO) no intestino dos animais expostos ao DSS quando comparados ao grupo de camundongos controles saudáveis, independentemente da presença do eixo HPA intacto e o tratamento com GC nos animais adrenalectomizados levou à redução significativa da atividade de MPO. Também foi observado na LP dos camundongos adrenalectomizados aumento significativo na frequência de células dendríticas tolerogênicas CD11b+CD11c+CD103+, T auxiliares (CD3+CD4+), T citolíticas (CD3+CD8+) e NKT (CD3+CD49b+), além de redução significativa da população de células dendríticas pró-inflamatórias CD11b+CD11c+CD103-, leucócitos CD11b+ e linfócitos intra-epiteliais, de maneira dependente de GC. A ausência do eixo HPA intacto levou à diminuição de leucócitos totais no baço quando comparados ao grupo com colite, relacionada principalmente à redução significativa na frequência de células NKT (CD3+CD49b+), as quais foram restauradas nos camundongos tratados com GC exógenos. Durante a exposição ao DSS houve aumento de células Th2 e Th1 no baço dos camundongos não adrenalectomizados, enquanto que a remoção das adrenais levou a notável redução na população de células T CD4 produtoras de IL-4, IL-10, IFN-? ou IL-17, com aumento de células Th17 e diminuição significativa de células Th1 no baço dos camundongos adrenalectomizados e tratados com GC. De forma interessante, houve menor acúmulo de células T reguladoras juntamente à redução na intensidade média de fluorescência (MFI) de FOXP3 em células T CD4+CD25+ do baço dos camundongos adrenalectomizados expostos ao DSS, de maneira geral dependente de GC. Por fim, esta diminuição de mecanismos reguladores foi acompanhada de menor índice de proliferação e aumento de IL-10 no sobrenadante de cultura de esplenócitos de camundongos com o eixo HPA não ii funcional, indicando que a ausência de GC endógenos pode alterar significativamente a homeostase do sistema imunológico. Juntos, nossos resultados demonstram que o eixo HPA é importante na modulação da resposta imunológica durante a colite induzida experimentalmente / Inflammatory bowel diseases (IBD) are caused by imbalance between regulatory and effector immune responses in the intestinal mucosa and can be modulated by the hypothalamic-pituitary-adrenal (HPA) axis via neuroimmune endocrine interactions and secretion of cortisol. Although glucocorticoids (GC) are used to treat IBD, cortisol produced by the adrenals glands is also involved in the stress response, which can lead to uncontrolled inflammatory diseases. Therefore, the aim of this study was to evaluate the HPA axis in the modulation of the immune response of intestinal mucosa. C57BL/6 mice were subjected to removal of the adrenal glands followed by induction of colitis by administration of water containing 3% dextran sulfate sodium (DSS). The results showed that the absence of adrenals led to increased susceptibility to disease and early mortality, a phenomenon that was not prevented by GC replacement. Adrenalectomized animals exposed to DSS had significantly lower levels of LPS, concomitantly to increased IL-6 in the serum when compared to non-adrenalectomized mice. In addition, adrenalectomized animals had lower cellularity in the lamina propria (LP), less erosion areas and less histopathologic score associated with increased IFN-? and FasL in the intestine, without compensatory local production of corticosterone. There was an increase in the activity of the myeloperoxidase (MPO) enzyme, N- acetilglicosaminidase (NAG) and eosinophil-peroxidase (EPO) in the intestines of DSS-exposed animals when compared to the healthy control group of mice, regardless of the presence of intact HPA axis, while treatment with GC led to significantly reduced MPO activity. It was also observed in the LP of adrenalectomized mice significant increase in the frequency of tolerogenic dendritic cells CD11b+CD11c+CD103+, helper T (CD3+ CD4+), cytolytic T (CD3+ CD8+) and NKT (CD3+ CD49b+) besides significant reduction in the population of pro-inflammatory dendritic cells CD11c+ CD11b+ CD103-, leukocyte CD11b+ and intraepithelial lymphocytes, GC-dependent manner. The absence HPA intact carried decrease in total leukocytes in spleen when compared to the group with colitis, related mainly to significant reduction in the frequency of NKT cells (CD3+CD49b+), which were restored in the GC treated mice. During exposure to DSS there was increased Th2 and Th1 cells in the spleen of non-adrenalectomized mice, while the removal of the adrenals was associated to a marked reduction in the population of CD4 T cells producing IL-4, IL-10, IFN-? or IL-17 with increased Th17 cells and significant decrease in Th1 cells in the spleen of adrenalectomized mice treated with GC. Interestingly there was less accumulation of regulatory T cells together to a reduction in mean fluorescence intensity (MFI) of FOXP3 in CD4+CD25+ T cells in the spleen of mice exposed to DSS after adrenalectomy, most dependent on GC. Finally, the decline of regulatory mechanisms was accompanied by lower rates of proliferation and increased IL-10 in the supernatant culture of splenocytes of mice with disrupted HPA axis, indicating that the absence of endogenous GC altered significantly the homeostasis of the immune system. Together, our results demonstrate that the HPA axis is important in modulating the immune response during experimentally induced colitis
28

Renal cell carcinoma : factors of importance for follow-up and survival

Iranparvar Alamdari, Farhood January 2007 (has links)
Background: Renal cell carcinoma (RCC) is most lethal of the urological cancers, with more than 40% dying of the disease. About 30% of the patients have metastases at initial diagnosis and up to 40% undergoing nephrectomy for localized RCC develop metastasis. A follow-up protocol based on accurate prognostic variables allows identification of low and high risk patients and selection of those most likely to benefit from adjuvant therapy. I have studied a number of prognostic patient-related factors, including tumour stage and grade, angiogenetic factors and tumour markers, in order to improve follow-up guideline as well as to try to predict prognosis and clinical outcome for individual patients. Material and Methods: The studies are based on patients treated for RCC between 1982 and 2002. All patients eligible for surgery with or without metastasis were treated with nephrectomy and were followed according to a scheduled follow-up programme. Serum samples were collected after obtained informed consent. Multiple clinicopathological, laboratory variables and preoperative radiological examinations were analyzed. Results: Study I- After nephrectomy in 187 patients with non-metastatic RCC, 30% developed metastases during the follow-up. The risk for metastases was greater for more advanced stage and was adjusted by size and DNA ploidy. The median time to the diagnosis of metastases was 14.5 months. Metastases occurred in 43% of the patients within one year, within 2 years in 70% and 80% in 3 years. Patients with tumours less than 5 cm and diploid pT1>5cm and pT2 tumours survived longer than those with larger and aneuploid tumours. The 5-years survival rate for pT1, pT2, pT3 tumours were 95%, 87%, and 37% respectively. In pT3 tumours DNA ploidy had no relation to survival time. Study II and IV- The median survival time for patients with metastatic RCC was 7 months. Cytoreductive nephrectomy was associated with longer survival time. Factors including performance status (PS), number of metastatic sites, erythrocyte sedimentation rate (ESR), calcium in serum, vein invasion, capsule invasion had independent prognostic value with Cox multivariate analysis. Study III- The incidence of adrenal tumour involvement was 5.3 %, unaffected of RCC type, tumour location or side. Gender (male) and locally advanced tumours (pT3 > 5cm) were factors predicting adrenal involvement. The presence of adrenal involvement was a significant adverse prognostic variable, indicating a significantly shorter survival in patients both with and without distant metastases. Conclusion: Optimal follow-up guidelines are important from both medical and economic perspectives. The risk for progression depends mainly on stage, which in combination with other prognostic factors may allow more individualized and cost effective follow-up, in some cases by avoiding unnecessary examinations in a third of the patients. Cytoreductive nephrectomy in patients with good PS, metastases limited to one organ, low ESR, normal calcium and no vein invasion were factors associated to long survival time. Soluble angiogenic factors in serum gave no prognostic information. Ipsilateral adrenalectomy in conjunction with radical nephrectomy should be performed if an adrenal lesion cannot be cleared of suspicion during preoperative work up. Ipsilateral adrenal involvement is a highly adverse prognostic factor and should be staged as M1a in the TNM staging system.
29

Participação do eixo hipotálamo-pituitária-adrenal na Doença Inflamatória Intestinal induzida experimentalmente / Participation of the hypothalamic-pituitary-adrenal axis in experimentally induced inflammatory bowel disease

Patrícia Reis de Souza 06 August 2015 (has links)
As doenças inflamatórias intestinais (DII) são causadas por desequilíbrio entre as respostas imunes efetoras e reguladoras na mucosa intestinal e podem ser moduladas pelo eixo hipotálamo-hipófise-adrenal (HPA) por meio de interações neuroimunoendócrinas e secreção de cortisol. Embora os glicocorticóides (GC) sejam utilizados para tratar a DII, o cortisol produzido pelas glândulas supra-renais também está envolvido na resposta ao estresse, que pode levar a doenças inflamatórias descontroladas. Portanto, o objetivo deste trabalho é avaliar a participação do eixo HPA na modulação da resposta imune de mucosa intestinal. Para tal, camundongos C57BL/6 foram submetidos à remoção das glândulas adrenais seguida por indução de colite pela administração de água contendo 3% de dextran sulfato de sódio (DSS). Os resultados demonstraram que a ausência das adrenais levou à maior suscetibilidade à doença e mortalidade precoce, fenômeno que não foi prevenido pela reposição de GC. Os animais adrenalectomizados com colite apresentaram níveis significativamente menores de LPS, concomitantemente ao aumento de IL-6 no soro quando comparados aos camundongos não adrenalectomizados. Além disso, os animais adrenalectomizados apresentaram menor celularidade na lâmina própria (LP), menos áreas de erosão e menor escore histopatológico associado ao aumento de IFN-? e FasL, no intestino, sem produção local compensatória de corticosterona. Houve aumento na atividade das enzimas mieloperoxidase (MPO), N- acetilglicosaminidase (NAG) e eosinófilo-peroxidase (EPO) no intestino dos animais expostos ao DSS quando comparados ao grupo de camundongos controles saudáveis, independentemente da presença do eixo HPA intacto e o tratamento com GC nos animais adrenalectomizados levou à redução significativa da atividade de MPO. Também foi observado na LP dos camundongos adrenalectomizados aumento significativo na frequência de células dendríticas tolerogênicas CD11b+CD11c+CD103+, T auxiliares (CD3+CD4+), T citolíticas (CD3+CD8+) e NKT (CD3+CD49b+), além de redução significativa da população de células dendríticas pró-inflamatórias CD11b+CD11c+CD103-, leucócitos CD11b+ e linfócitos intra-epiteliais, de maneira dependente de GC. A ausência do eixo HPA intacto levou à diminuição de leucócitos totais no baço quando comparados ao grupo com colite, relacionada principalmente à redução significativa na frequência de células NKT (CD3+CD49b+), as quais foram restauradas nos camundongos tratados com GC exógenos. Durante a exposição ao DSS houve aumento de células Th2 e Th1 no baço dos camundongos não adrenalectomizados, enquanto que a remoção das adrenais levou a notável redução na população de células T CD4 produtoras de IL-4, IL-10, IFN-? ou IL-17, com aumento de células Th17 e diminuição significativa de células Th1 no baço dos camundongos adrenalectomizados e tratados com GC. De forma interessante, houve menor acúmulo de células T reguladoras juntamente à redução na intensidade média de fluorescência (MFI) de FOXP3 em células T CD4+CD25+ do baço dos camundongos adrenalectomizados expostos ao DSS, de maneira geral dependente de GC. Por fim, esta diminuição de mecanismos reguladores foi acompanhada de menor índice de proliferação e aumento de IL-10 no sobrenadante de cultura de esplenócitos de camundongos com o eixo HPA não ii funcional, indicando que a ausência de GC endógenos pode alterar significativamente a homeostase do sistema imunológico. Juntos, nossos resultados demonstram que o eixo HPA é importante na modulação da resposta imunológica durante a colite induzida experimentalmente / Inflammatory bowel diseases (IBD) are caused by imbalance between regulatory and effector immune responses in the intestinal mucosa and can be modulated by the hypothalamic-pituitary-adrenal (HPA) axis via neuroimmune endocrine interactions and secretion of cortisol. Although glucocorticoids (GC) are used to treat IBD, cortisol produced by the adrenals glands is also involved in the stress response, which can lead to uncontrolled inflammatory diseases. Therefore, the aim of this study was to evaluate the HPA axis in the modulation of the immune response of intestinal mucosa. C57BL/6 mice were subjected to removal of the adrenal glands followed by induction of colitis by administration of water containing 3% dextran sulfate sodium (DSS). The results showed that the absence of adrenals led to increased susceptibility to disease and early mortality, a phenomenon that was not prevented by GC replacement. Adrenalectomized animals exposed to DSS had significantly lower levels of LPS, concomitantly to increased IL-6 in the serum when compared to non-adrenalectomized mice. In addition, adrenalectomized animals had lower cellularity in the lamina propria (LP), less erosion areas and less histopathologic score associated with increased IFN-? and FasL in the intestine, without compensatory local production of corticosterone. There was an increase in the activity of the myeloperoxidase (MPO) enzyme, N- acetilglicosaminidase (NAG) and eosinophil-peroxidase (EPO) in the intestines of DSS-exposed animals when compared to the healthy control group of mice, regardless of the presence of intact HPA axis, while treatment with GC led to significantly reduced MPO activity. It was also observed in the LP of adrenalectomized mice significant increase in the frequency of tolerogenic dendritic cells CD11b+CD11c+CD103+, helper T (CD3+ CD4+), cytolytic T (CD3+ CD8+) and NKT (CD3+ CD49b+) besides significant reduction in the population of pro-inflammatory dendritic cells CD11c+ CD11b+ CD103-, leukocyte CD11b+ and intraepithelial lymphocytes, GC-dependent manner. The absence HPA intact carried decrease in total leukocytes in spleen when compared to the group with colitis, related mainly to significant reduction in the frequency of NKT cells (CD3+CD49b+), which were restored in the GC treated mice. During exposure to DSS there was increased Th2 and Th1 cells in the spleen of non-adrenalectomized mice, while the removal of the adrenals was associated to a marked reduction in the population of CD4 T cells producing IL-4, IL-10, IFN-? or IL-17 with increased Th17 cells and significant decrease in Th1 cells in the spleen of adrenalectomized mice treated with GC. Interestingly there was less accumulation of regulatory T cells together to a reduction in mean fluorescence intensity (MFI) of FOXP3 in CD4+CD25+ T cells in the spleen of mice exposed to DSS after adrenalectomy, most dependent on GC. Finally, the decline of regulatory mechanisms was accompanied by lower rates of proliferation and increased IL-10 in the supernatant culture of splenocytes of mice with disrupted HPA axis, indicating that the absence of endogenous GC altered significantly the homeostasis of the immune system. Together, our results demonstrate that the HPA axis is important in modulating the immune response during experimentally induced colitis
30

Lesion level-dependent glucocorticoid dysregulation exacerbates systemic muscle wasting during the acute phase of paraplegic rodent spinal cord injury

Harrigan, Markus E. 12 September 2022 (has links)
No description available.

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