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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.
1

Understanding the role of zinc in IL-1β production

Summersgill, Holly January 2013 (has links)
Zinc is an essential biological trace element required for proper immune functioning. Zinc deficient individuals have been reported to suffer compromised immune responses and increased levels of inflammatory cytokines. Inflammation is integral to the pathology of many disease states, ranging from pathogen dependent infectious disease to non-infectious disease such as cancer, heart disease, diabetes and stroke. One of the main mediators of inflammation is the pro-inflammatory cytokine interleukin-1beta (IL-1beta). Production of IL-1beta occurs via a two step process; firstly the transcription of an inactive pro-form is initiated, followed by protease activation leading to the cleavage of IL-1beta to a mature form. Here it is shown that in vitro zinc depletion of macrophages, using the zinc chelators TPEN and DTPA, leads to pro-IL-1beta cleavage and furthermore to increased release of active IL-1beta. This would suggest that zinc depletion induces activation of proteases that cleave IL-1beta. Caspase-1, ASC, PP2A, cathepsin B and cathepsin G are all shown to regulate zinc depletion-induced IL-1beta release in macrophages. The cell death proteins XIAP and caspase-8 have also been identified to be regulated by zinc depletion in macrophages and there is literature to suggest that these proteins may contribute to IL-1beta processing and release. By identifying a role for zinc depletion in IL-1beta processing we move closer to identifying potential therapeutic targets for zinc deficiency induced inflammatory disease. Zinc also has regulatory roles in the expression of IL-1beta. Here a systems biology approach is utilised to create an explicit representation of the pathways involved in IL-1beta expression. In many in vivo and in vitro models, transcription of pro-Interleukin-1beta is induced by the gram negative cell wall component lipopolysaccharide (LPS). A systematically curated network map of IL-1 transcription has been created. The map encompasses interactions at the macrophage cell membrane, where LPS binds Toll-like receptor 4 (TLR4); the resulting cytoplasmic signalling cascades, including MAPK and NF-kappaB; and finally the specific transcription factor interactions in the nucleus. By creating this model we aim to enable the production of dynamic models of IL-1 transcription.
2

The role of catabolin in experimental osteoarthritis

Sabiston, C. Paul January 1985 (has links)
The pathogenesis of osteoarthritis (OA) is complex, but likely involves destruction of articular cartilage by endogenous enzymes (Dingle 1979). Factors controlling this are not well understood. Cetabolin, a 21,000 molecular weight peptide structurally end functionally related to interleukin-1, stimulates living but not killed chondrocytes in vitro to degrade their matrix (Fell and Jubb 1977, Saklatvala et al. 1983), suggesting it is not itself a degradative enzyme but functions as a control factor. The work in this thesis investigated the possible role of cetabolin in the pethogenesis of OA by measuring catabolin production by cultures of synovium excised from the canine anterior cruciate ligament transection model of OA. Normal cenine synovium in culture was shown to produce a factor which can stimulate the release of glycoseminoglycens from living cenine articular cartilage in culture. The total emount of cetebolin produced by cultures of synovium from experimentally induced OA synovium is statistically significantly greater (p<0.05) than that produced by normal synovium. When calculated per gram of synovium, there was no statistically significant difference. This suggests that a possible role for cetebolin in the pathogenesis of OA might be related to the degree of synovial hypertrophy. / Medicine, Faculty of / Graduate
3

A Interleucina 1 'beta' desempenha um papel termogênico na inflamação hipotalâmica induzida por dieta em ratos / Interleukin 1 'beta' plays a thermogenic role in diet-induced hypothalamic inflammation

Biazzo, Lívia Aparecida D'Avila Bitencourt Pascoal 19 August 2018 (has links)
Orientadores: Lício Augusto Velloso, Marciane Milanski / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T22:36:19Z (GMT). No. of bitstreams: 1 Biazzo_LiviaAparecidaD'AvilaBitencourtPascoal_M.pdf: 4154170 bytes, checksum: 19b0d87fbb38f934ea580317356be4bf (MD5) Previous issue date: 2012 / Resumo: Na obesidade experimental, mudanças na função hipotalâmica desempenham papel importante na regulação anômala da ingestão alimentar e do gasto energético. Estudos recentes mostram que a inflamação hipotalâmica sub-clínica é um importante fator que contribui para a disfunção hipotalâmica na obesidade. Citocinas, como TNF'alfa', IL6 e IL10 tem sido estudadas no hipotálamo de modelos animais de obesidade, entretanto, o papel da IL1? nesta condição não está claro. Neste trabalho, nós utilizamos a técnica de interferência de RNA conjugado com o peptídeo do vírus da raiva RVG-9R para direcionar a molécula antisense de IL1? ao sistema nervoso central. Essa manipulação levou a uma redução de 50% na expressão hipotalâmica de IL1 ? em ratos obesos e a um aumento do ganho de peso corporal sem afetar a ingestão alimentar e a atividade física espontânea. A redução da expressão da IL1? no sistema nervoso central foi acompanhada da redução da atividade da enzima citrato sintase da cadeia respiratória mitocondrial e ao aumento da expressão de PGC1'alfa' no tecido adiposo marrom desses animais. Assim, propomos que a expressão de IL1? no hipotálamo de ratos obesos leva ao aumento da termogênese no tecido adiposo marrom que protege contra o ganho de massa corporal excessiva / Abstract: In experimental obesity, changes in hypothalamic function play an important role in the anomalous regulation of food intake and energy expenditure. Recent studies have shown that a low-grade hypothalamic inflammation is an important factor contributing to hypothalamic dysfunction in this context. Cytokines such as TNF'alfa', IL6 and IL10 have been studied in the hypothalamus of experimental models of obesity, however, the role played by IL1? in this condition is unknown. Here we employed small-intereference RNA conjugated with the rabies virus RVG-9R peptide to deliver an IL1? antisense RNA to the central nervous system. This approach led to a 50% reduction of hypothalamic expression of IL1? in obese rats and produced an increase in body mass gain without affecting food intake and spontaneous physical activity. Upon central nervous system IL1? inhibition the brown adipose tissue activity of the respiratory chain mitochondria enzyme citrate synthase was reduced, while the expression of PGC1'alfa'? was increased. Thus, the expression of IL1? in the hypothalamus of obese rats provides a brown adipose tissue-dependent thermogenic mechanism that protects against excessive body mass gain / Mestrado / Medicina Experimental / Mestre em Fisiopatologia Médica
4

The role of interleukin-1beta on the expression of nestin in cardiac neural stem cells following myocardial infarction

Khan, Alexandre 12 1900 (has links)
Le mécanisme biologique responsable pour l’augmentation de l’expression de la protéine nestin dans les cellules souches neurales (CSN) du cœur après un infarctus du myocarde (IM) demeure inconnu. Des études antérieures ont démontré que le traitement au dexamethasone, un glucocorticoïde aux propriétés anti-inflammatoires, abolit la régulation positive de nestin après un IM. Ceci suggère un lien avec la réponse inflammatoire. Nous avons vérifié dans cette étude l’hypothèse que la cytokine inflammatoire interleukin-1beta (IL-1beta) peut modifier le phénotype de cellules souches neurales. Le deuxième objectif de l’étude fut d’établir l’impact, suivant un IM, de l’inhibition de la signalisation de IL-1beta sur la fonction et la guérison cardiaque. Suite à une ligature complète de l’artère coronaire du rat mâle, le dysfonctionnement contractile du ventricule gauche fut associé à une régulation positive de la protéine nestin dans le myocarde non-infarci. Le traitement avec Xoma 052 (1 mg/kg), un anticorps anti-IL-1beta, 24h, 7 et 14 jours après un évènement ischémique, eu aucun effet sur la taille de l’infarctus ou la contractilité du ventricule gauche. De plus, le traitement avec Xoma 052 après un IM n’a pu supprimer l’augmentation de l’expression de nestin et Bcl-2 malgré une réduction modeste du niveau de la protéine Bax. Pour déterminer directement le rôle de la réponse inflammatoire en l’absence d’ischémie, nous avons injecté des rats mâles avec du LPS (10mg/kg, 18hrs). Dans le coeur du rat-LPS, nous avons noté une augmentation significative du niveau d’ARNm de IL-1beta et de l’expression de la protéine nestin. Le prétraitement avec 10mg/kg de Xoma 052 a aboli l’augmentation de l’expression de nestin dans le coeur des rats-LPS. Ces observations indiquent que les cellules souches neurales pourraient représenter une cible potentielle de l’IL-1beta. / The underlying biological event(s) implicated in the increased expression of nestin in cardiac resident neural stem cells (NSC) following myocardial infarction (MI) remain unknown. Past studies have shown that dexamethasone treatment, a synthetic glucocorticoid with potent anti-inflammatory properties, abolished the upregulation of nestin in the non-infacted left ventricle (NILV) following MI. This suggests an association with the inflammatory response. The present study tested the hypothesis that the inflammatory cytokine interleukin-1beta (IL-1beta) can influence the neural stem cell phenotype. A secondary goal of the study was to assess impact of IL-1beta signalling inhibition on cardiac function and wound healing following MI. Following complete coronary artery ligation of the adult male rat heart, left ventricular contractile dysfunction was associated with the upregulation of the pro-apoptotic protein bax, the anti-apoptotic protein Bcl-2 and nestin in the non-infarcted myocardium. Xoma 052 (1 mg/kg), an IgG antibody directed against IL-1beta, was administred 24 hrs after ischemic injury and subsequently injected 2x over a period of 21 days. Treatment did not alter infarct size or improve left ventricular contractility. In addition, it failed to abolish the increased expression of nestin and Bcl-2, and modestly reduced bax protein levels. To directly assess the relationship between inflammation and the expression of nestin in the absence of an ischemic insult, adult male rats were injected with lipopolysaccharide (LPS) (10mg/kg;18 hrs). In the heart of LPS- treated rats, IL-1beta mRNA levels were significantly increased and associated with elevated nestin protein expression. The pre-treatment with Xoma 052 (10mg/kg) abolished the increased expression of nestin in the heart of LPS-treated rats. These data indicate that neural stem cells may represent a target for IL-1beta. However, futher investigation is required to elucidate the role of IL-1beta on NSC following MI.
5

Molecular Mechanisms of Interleukin-1beta-Stimulated Regulation of Angiogenesis in Cardiac Microvascular Endothelial Cells.

Mountain, Deidra Jill Hopkins 15 December 2007 (has links)
Angiogenesis, the formation of new vessels from a preexisting vasculature, is critical for supplying a healing myocardium with oxygen and nutrients to sustain metabolism post myocardial infarction (MI). Interleukin-1β (IL-1β), a proinflammatory cytokine increased in the heart post-MI, is considered essential for angiogenesis in tumor growth and metastasis, arthritis, endometriosis, and wound healing. Matrix metalloproteinases (MMPs) are implicated in angiogenesis because of their ability to selectively degrade components of the extracellular matrix. Vascular endothelial growth factors (VEGFs) play a vital role in angiogenesis because of their involvement in the recruitment and proliferation of endothelial cells. The current study explores IL-1β-stimulated regulation of angiogenic genes in cardiac microvascular endothelial cells (CMECs), the signaling mechanisms involved, and the implications in the processes of angiogenesis. DNA microarray analysis indicated IL-1β modulates the expression of numerous angiogenesis-related genes, notably upregulating MMP-2 and downregulating VEGF-D expression. RT-PCR and Western blot analyses confirmed the differential expression in response to IL-1β. In-gel zymographic analysis demonstrated IL-1β-stimulated increase in MMP-2 activity. IL-1β activated ERK1/2 and JNKs, not p38 kinase, and activated PKCα/β1 independent of MAPKs. IL-1β inactivated GSK3β via ERK1/2. Pharmacological inhibition of these signaling cascades indicated IL-1β-stimulated regulation of MMP-2 and VEGF-D occurs via ERK1/2, JNKs, and PKCα/β1-dependent mechanisms. In addition, inactivation of GSK3β inhibited basal VEGF-D expression. H2O2 significantly increased MMP-2 protein levels while IL-1β-induced VEGF-D downregulation was further potentiated by ROS scavenging compounds and inhibition of NF-κB. Phalloidin-FITC stain indicated a sharp reduction in fibrillar actin in the cytoskeleton of IL-1β-stimulated cells. Wounding assays revealed that IL-1β induced CMEC migration but prevented cell-to-cell contact and restoration of the monolayer. Flow cytometric analysis revealed a G0/G1 phase cell cycle arrest in IL-1β-stimulated cells, indicative of decreased proliferation. IL-1β inhibited three-dimensional in vitro tube formation by CMECs. Lastly, IL-1β inhibited microvessel sprouting from aortic rings, an assay examining the collective response of multiple cell types. Collectively, the data presented in this study provide evidence that IL-1β differentially regulates important angiogenesis-related genes in CMECs. This differential regulation may lead to interruptions in the processes of angiogenesis, ultimately creating a dysfunctional phenotype for myocardial vessel formation.
6

Neue Modulatoren des P2X7-Rezeptors

Hempel, Christoph 26 February 2015 (has links) (PDF)
P2X7-Rezeptoren stellen Schlüsselmoleküle bei der Entstehung und Aufrechterhaltung proinflammatorischer Zustände, chronischer Schmerzen sowie der neuroglialen Kommunikation dar. Ihre Aktivität wird durch eine Vielzahl zellbiologischer Mechanismen beeinflusst. Dazu gehört die allosterische Modulation durch extrazelluläre niedermolekulare Stoffe. Die Entwicklung selektiver und potenter P2X7-Modulatoren ist darum Gegenstand intensiver Forschung. Bisher sind jedoch keine Pharmaka für die klinische Anwendung verfügbar. Die Untersuchung zugelassener pharmakologischer Substanzen in einem akademischen Screening erbrachte eine hohe Trefferrate für P2X7-Rezeptoren. In dieser Arbeit wird die P2X7-Wirkung einiger der potentesten allosterischen Modulatoren genauer charakterisiert. Das Antihistaminikum Clemastin stellt dabei einen positiven allosterischen Modulator dar, der den Rezeptor gegenüber niedrigeren ATP-Konzentrationen sensibilisiert. Ivermectin, ein häufig angewendetes Anthelminthikum, konnte als potenzierender Modulator des humanen P2X7-Rezeptors charakterisiert werden. Mit den Phenothiazinen Prochlorperazin und Trifluoperazin zeigen sich schließlich ZNS-gängige Inhibitoren der ATP-induzierten P2X7-Aktivität, die für weiterführende in vivo-Untersuchungen hilfreiche pharmakologische Werkzeuge darstellen können.
7

Participação do HIF-1'alfa' na expressão de colageno tipo II e agrecano na cartilagem articular mediada pela IL-1'beta' e TNF'alfa' / The participation of HIF-1'alpha' in collagen type II and aggrecan expression on articular cartilage mediated by IL-1'beta' and TNF'alpha' cytokines

Sartori, Angelica Rossi 12 August 2018 (has links)
Orientador: Ibsen Bellini Coimbra / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-12T21:15:58Z (GMT). No. of bitstreams: 1 Sartori_AngelicaRossi_D.pdf: 3838547 bytes, checksum: 0be815456ed0b3b8faf496ae6738da31 (MD5) Previous issue date: 2009 / Resumo: O Fator Induzido por Hipóxia-1 (Hypoxia Inducible Factor-1 - HIF-1) é um fator de transcrição responsável por transcrever genes relacionados às alterações nas concentrações de oxigênio e sobrevivência celular. A cartilagem articular é um tecido avascular e o ambiente dos condrócitos é caracterizado por condições de hipóxia dentro da matriz. Nestas condições a proteína HIF-1alfa do Fator de transcrição Induzido por Hipóxia-1alfa (HIF-1alfa) é necessário para controlar o metabolismo e a integridade funcional da cartilagem. Além da hipóxia algumas citocinas como IL-1? e TNF? são também capazes de estabilizar HIF-1?, além de serem consideradas as principais mediadoras da osteoartrite (OA). Objetivo: Verificar a participação da IL-1? na regulação do HIF-1? em condições normais de oxigênio; Verificar a utilização da via da Fosfatidil-Inositol-3-Kinase (PI-3K) pelo HIF-1? e analisar a participação HIF-1? na expressão de colágeno tipo II e agrecano e a sua regulação pelas citocinas TNF-? e da IL-1?. Material e Métodos: Condrócitos humanos provenientes de pacientes em OA, submetidos à artroplastia de joelho, foram cutivados em suspensão e em monocamada, submetidos ou não ao silenciamento do gene do HIF-1? pela técnica de Interferência por RNA e estimulados com IL-1?, TNF? e LY294002, o inibidor da via da PI-3K em condições normais de oxigênio e em hipóxia e foram submetidos à extração de proteína nuclear, extração de RNA e precipitação das proteínas do meio de cultura das células. A análise das proteínas foi feita por meio da técnica de Western Blotting para a detecção da proteína nuclear HIF-1? e do colágeno tipo II no meio de cultura das células. O RNA foi analisado pela técnica de PCR em Tempo Real para a quantificaçãos dos genes do HIF-1?, Colágeno tipo II e Agrecano. Resultados: IL-1? aumentou a expressão da proteína nuclear HIF-1?, mas não alterou a expressão do RNAm. Essa modulação utilizou a via da PI-3K. A hipóxia aumentou as concentrações do RNAm do HIF-1? em comparação com as condições normais de oxigênio, mas IL-1? e TNF? não alteraram o RNAm do HIF- 1? em condições normais de oxigênio e em associação com a hipóxia, inibiram o efeito regulatório positivo desta sobre o HIF-1?. A hipóxia isoladamente também aumentou RNAm de colágeno tipo II, o que foi anulado pelo estímulo associado com a IL-1?. Nos grupos de condrócitos com deficiência do HIF-1? (silenciados), em quaisquer condições de oxigênio, IL-1? e TNF? não alteraram significativamente a expressão de HIF-1?, mas em hipóxia, a expressão de colágeno tipo II foi regulada negativamente nesses grupos. A associação entre a falta do HIF-1? e as citocinas diminuiu ainda mais a expressão do colágeno tipo II em condições de hipóxia. Em todas as análises não foram observadas diferenças significativas nas expressões do RNAm do agrecano e na análise do colágeno tipo II das proteínas precipitadas dos meios de cultura das células. Conclusão: IL-1? aumentou a expressão da proteína nuclear HIF-1? pós-transcrição. A regulação do HIF-1? pela IL-1? em situação normal de oxigênio ocorreu, ao menos em parte, pela PI-3K. O HIF-1? se relacionou positivamente com a expressão do gene do colágeno tipo II, principalmente em hipóxia, mas não com os níveis da proteína. Não houve associação com a expressão do gene do agrecano / Abstract: Introduction: Hypoxia Inducible Factor -1 (HIF-1) is a transcription factor that regulates the expression of genes related with oxygen concentration e cellular survive. Articular cartilage is a non-vascular tissue and the condrocytes microenviroment are caracterized by hypoxic conditions inside the extracelluar matrix. In this condition, the protein HIF-1?, from HIF-1 is necessary to the metabolism control and cartilage functional intengrity. Some citokines like IL-1? and TNF?, as well as hypoxia, are capable to stabilize HIF-1? and are essential in oateoarthritis (OA) progression disease. Objective: To verify the participation of IL-1? in the HIF-1? regulation under normal conditions of oxygen; To verify if the pathway of phosphatidilynositol-3-Kinase (PI-3K) is used in this modulation; To analyse HIF-1? participation in the collagen type II and aggrecan gene expression and your regulation by TNF-? and IL-1?. Material and Methods: Human OA chondrocytes were obtained from patients with OA that underwent total knee joint replacement surgery, were cultured either in suspension or monolayer. They were submitted to HIF-1? gene silencing by RNA Interference and lately stimulated with IL-1?, TNF? and LY294002, a specific inhibitor to Phosphatidilinosiltol - 3- Kinase (PI-3K) pathway in normal conditions of oxygen and in hypoxia. The condrocytes were submitted to protein nuclear extraction, RNA extraction and protein precipitation of culture media from the experiments. The proteins were analyzed by Western Blotting to HIF-1? detection in nuclear extraction and collagen type II detection in precipitated media. The RNA were analized by Real Time PCR to HIF- 1?, collagen type II and aggrecan gene quantification. Results: HIF-1? expression is up-regulated by IL-1? at the protein level but not in the mRNA expression. This modulation used, at least in part, the PI-3K pathway. Hypoxia enhanced the mRNA concentrations of HIF-1? when compared with normal conditions of oxygen, but in this cases IL-1? and TNF? did not change mRNA expression of HIF-1?. In association with hypoxia, these citokines inhibited the positive regulatory effect under HIF-1? mRNA expression. Hypoxia up-regulated collagen type II gene expression and that was inhibited by the association with IL-1?. In the groups with lack of HIF-1? (silenced), in both oxygen conditions, IL-1? and TNF? did not cause any significant change of the HIF-1? mRNA expression, but in hypoxia, collagen type II was up-regulated in those groups. The association between the lack of HIF- 1? and citokines down-regulated more strongly collagen type II in hypoxia. In all analyzes it was not observed significant differences in the aggrecan mRNA expression and collagen tipe II protein from cultured media of the cells Conclusion: IL-1? post-trancriptionaly up-regulated the HIF-1? protein level. HIF- 1? regulation by IL-1? in normal conditions of oxygen used, at least in part, the PI- 3K pathway. HIF-1? positively related with gene expression, but not with the protein levels, of collagen type II, mainly in hypoxia. There was no relation in the HIF-1? and aggrecan gene expression / Doutorado / Ciencias Basicas / Doutor em Clínica Médica
8

Aspirin Triggered Resolution Phase Interaction Product D1: A Novel Treatment for Hyperoxic Acute Lung Injury

Cox, Jr., Ruan Rollin 13 July 2015 (has links)
Acute Lung injury (ALI) and the more severe acute respiratory distress syndrome (ARDS) are respiratory maladies that present immense clinical challenges. ALI affects 200,000 individuals annually and features a 40% mortality rate. ALI can be initiated by both pathogenic and sterile insults originating locally in the lungs or systemically. While immense research has been poured into this disease in an effort to find a therapeutic strategy, the heterogeneously diffuse nature of the disease has not yielded a cure for the disease. Death from this disease is strongly attributed to reduced gas exchange from a severely compromised alveolar-capillary barrier. The only way currently to manage this disease is through enhanced ventilation and hyperoxic therapy. Hyperoxic therapy is a common treatment given to over 800,000 patients each year to treat respiratory maladies such as ALI. Prolonged exposure to oxygen at high concentrations results in the development of a condition known as hyperoxic acute lung injury (HALI). In this disease, the formation of reactive oxygen species damages healthy tissue and impairs gas exchange. Hyperoxia is also a well-documented murine sterile lung injury model that replicates the symptoms of ALI in lung injury patients. The ability of non-lethal dosages of hyperoxia to resolve without lung fibrosis also enables the study of molecules associated with ALI resolution and repair, a process not clearly understood. Inflammation in ALI is associated with disease progression, however pharmaceutical interventions aimed at targeting the inflammatory cascade have failed in clinical trials for ALI. Recent reports point to an aberrant injury resolution mechanisms that may be more strongly correlated with morbidity and mortality. There seems to be a homeostatic imbalance between endogenous inflammation progression and resolution initiation. This is especially the case with HALI, as significant ROS generation results in depletion of redox regulating antioxidants. Resolution mechanisms associated with ALI in the oxygen toxicity setting is poorly understood. Polyunsaturated fatty acids such eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are essential fatty acids that show immense antioxidant and anti-inflammatory action in cases of acute injury. The lung mucosa is rich in DHA and following inflammatory insult DHA is readily converted to resolution phase interaction products (resolvins), which have shown immense proresolutionary potential in recent reports of acute injury. In the presence of aspirin, more potent and longer-acting aspirin-triggered resolvins are formed. The effects of resolvins and their aspirin triggered epimers have not been studied in an oxygen toxicity setting and are the focus of this dissertation. For the first time, we show that one of these resolvin molecules, aspirin triggered resolvin d1 (AT-RvD1), can enhance resolution of hyperoxic acute lung injury. In vitro results reveals that AT-RvD1 treatment resulted in reduced interaction of two key players in the HALI inflammatory cascade, the macrophage and alveolar epithelium. AT-RvD1 was able to blunt macrophage cytokine secretion as well as inhibit epithelial cell cytokine secretion and adhesion molecule expression. More importantly, AT-RvD1 blunted cytokine mediated leukocyte-epithelial cell interaction in vitro. In a sublethal hyperoxic injury model, mice given AT-RvD1 following hyperoxia exposure displayed reduced HALI pathological severity. ATRvD1 treatment resulted in reduced alveolar-capillary permeability, tissue inflammation, proinflammatory mediator secretion, epithelial cell death, and leukocyte influx. Taken together these novel results demonstrate the therapeutic potential of resolvins in the oxygen toxicity setting. These results also arouse the idea that resolvins could be used to lessen the comorbidities associated with oxygen therapy and improve recovery times of ALI patients.
9

Associação entre o polimorfismo +3954 do gene da interleucina-1 beta, obesidade, LDL-oxidado e seu potencial efeito lipotóxico / Association between interleukin-1 beta gene, obesity, LDL-oxidade and its lipotoxicity effect potencial

Cattani, Maria Fernanda Manica Rizzi 06 March 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Obesity is a systemic low grade inflammation, that is associated to the increased production of proinflammatory molecules by adipose tissue. Besides, the adiposity elevated induces cellular apoptosis and release of a large amounts of free fatty acids from disrupted adipocyte. These molecules tend to accumulate in the liver and other body tissues like skeletal muscles causing a phenomenon known as lipotoxicity. Evidence suggests that in addition to fatty acids there are other molecules that could have a severe effect lipotoxicity. This is the case of the inflammatory cytokine interleukin 1 beta (IL-1β). The IL-1β is a major inflammatory cytokines in immunity system. Studies suggest that its continued production may act by reducing the glucose influx, and induces the free radicals production contributing to the maintenance of a state of oxidative stress. For this reason, some authors have suggested that IL-1β would be a molecule glicolipotóxic. In humans the expression of IL-1B is under strong genetic control. The single nucleotide polymorphism (SNP) of C to T at nucleotide position +3953 of the IL-1B gene appears to be functional because it has been associated with increased production of IL-1β in vivo. Therefore, the aim of this study was to analyze the association between the polymorphism +3953 IL-1B gene with obesity, the influence on glycemic control, lipid and oxidized LDL molecule (oxLDL). For this, two studies were performed. The first was a case-control study with 880 Caucasian individuals, classified to obesity (non-obese = 283, overweight = 334, obese = 263), age between 18-92 years, and genotyped to IL-1B +3953 polymorphism. It was measured the bioanthropometric variables (DBP, SBP, IBM, height, weight, waist circumference) and serum parameters of blood glucose, lipid profile. In the second study, we included 225 subjects genotyped previously and measured the oxLDL serum levels, besides bioanthropometric and lipid profile measures. In both studies the volunteers did not smoke and had no cardiovascular disease or chronic degenerative diseases that could affect results. The IL-1B polymorphism genotypes were determined by PCR-RFLP and biochemical parameters by spectrophotometry. The first study results showed that the C allele (CC and CT) had a higher frequency in the group of obese and overweight when compared to the non obese group. The odds ratio showed 1.340 (95% CI: 1.119-1.605) times more chance of the obese group being CC carriers compared to non-obese group independent of gender and age. The second study showed that TT genotype carriers presented lower levels of oxLDL than patients with other genotypes. However no significant influence was observed of this polymorphism in blood glucose levels. Multivariate analysis showed that this result is independent of sex, age, obesity and hypertension. Thus, these results support the hypothesis that IL-1β is a molecule indeed obesogenic and lipotoxicity as previously suggested from animal models studies. Key-word: obesity. Interleukin-1beta. Oxidized-LDL / A obesidade é um inflamação sistêmica de baixo grau associado a elevada liberação de moléculas pró-inflamatórias pelo tecido adiposo. O aumento da adiposidade resulta em necrose tecidual e liberação de ácidos graxos, a partir dos adipócitos, que tendem a se acumular em outros tecidos corporais causando um fenômeno conhecido como lipotoxicidade. A IL-1β é uma das principais citocinas pró-inflamatórias do sistema imune, e a sua produção continuada pode agir diminuindo o influxo da glicose para dentro da célula, e induzir a produção de radicais livres contribuindo para a manutenção de um estado de estresse oxidativo. Por este motivo, alguns autores sugeriram que a IL- 1β seria uma molécula glicolipotóxica. Nos seres humanos a IL-1β possui um polimorfismo +3953 do gene da IL-1B parece ser funcional pois tem sido associado a variações na produção da IL-1β in vivo. Portanto, o objetivo deste estudo foi o de analisar a associação entre o polimorfismo +3953 do gene da IL-1B com a obesidade, a influencia nos níveis glicêmicos, lipídicos e da molécula de LDL- oxidado (LDL-ox). Para isso, foram realizados dois estudos. O primeiro foi um estudo caso-controle com 880 indivíduos Caucasianos classificados para obesidade (não obesos= 283, sobrepeso=334, obesos= 263), com idade entre 18 e 92 anos, genotipados para IL-1B +3953 determinados por PCR-RFLP. As variáveis PAD, PAS, circunferência abdominal, IMC, altura, peso, bem como o perfil glicêmico e lipídico foram medidos. No segundo estudo foram selecionados 225 indivíduos, previamente genotipados para IL-1B +3953, e medido os níveis séricos de LDL-ox, além das medidas bioantropométricas e perfil glicêmico e lipídico. Em ambos os estudos os voluntários não fumavam e não apresentavam doenças cardiovasculares ou crônico-degenerativas que pudessem interferir nos resultados. Os resultados, do primeiro estudo, mostraram que o alelo C (CT CC) apresentou uma frequência maior no grupo dos obesos e sobrepeso quando comparado ao grupo dos não obesos. A chance dos indivíduos obesos de serem portadores do genótipo CC foi de 1,34 (IC 95%, 1,119- 1,605). Estes resultados foram independente do gênero e idade. O segundo estudo mostrou que indivíduos com o genótipo CC e CT apresentaram níveis mais elevados de LDL-ox do que os portadores do genótipo TT. A análise multivariada mostrou que este resultado é independente do gênero, idade e obesidade. Entretanto, em ambos os estudos, não foi observada influência deste polimorfismo nos níveis glicêmicos. Assim, podemos concluir que a IL-1β é uma molécula, com efeito obesogênico e lipotóxico, corroborando estudos prévios em modelos animais.
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Neue Modulatoren des P2X7-Rezeptors

Hempel, Christoph 25 September 2014 (has links)
P2X7-Rezeptoren stellen Schlüsselmoleküle bei der Entstehung und Aufrechterhaltung proinflammatorischer Zustände, chronischer Schmerzen sowie der neuroglialen Kommunikation dar. Ihre Aktivität wird durch eine Vielzahl zellbiologischer Mechanismen beeinflusst. Dazu gehört die allosterische Modulation durch extrazelluläre niedermolekulare Stoffe. Die Entwicklung selektiver und potenter P2X7-Modulatoren ist darum Gegenstand intensiver Forschung. Bisher sind jedoch keine Pharmaka für die klinische Anwendung verfügbar. Die Untersuchung zugelassener pharmakologischer Substanzen in einem akademischen Screening erbrachte eine hohe Trefferrate für P2X7-Rezeptoren. In dieser Arbeit wird die P2X7-Wirkung einiger der potentesten allosterischen Modulatoren genauer charakterisiert. Das Antihistaminikum Clemastin stellt dabei einen positiven allosterischen Modulator dar, der den Rezeptor gegenüber niedrigeren ATP-Konzentrationen sensibilisiert. Ivermectin, ein häufig angewendetes Anthelminthikum, konnte als potenzierender Modulator des humanen P2X7-Rezeptors charakterisiert werden. Mit den Phenothiazinen Prochlorperazin und Trifluoperazin zeigen sich schließlich ZNS-gängige Inhibitoren der ATP-induzierten P2X7-Aktivität, die für weiterführende in vivo-Untersuchungen hilfreiche pharmakologische Werkzeuge darstellen können.:1. Bibliographische Beschreibung 4 2. Abkürzungsverzeichnis 5 3. Einleitung 6 Überblick über die purinerge Signalübertragung 6 Pathophysiologische Bedeutung des P2X7-Rezeptors 8 Speziesspezifische Eigenschaften des P2X7-Rezeptors 10 P2X7-Rezeptoren in der Pharmakotherapie 10 Rationale der Studie 11 Clemastin 12 Ivermectin 12 Die Neuroleptika Prochlorperazin und Trifluoperazin 13 4. Publikationen 15 5. Zusammenfassung der Arbeit 64 6. Literaturverzeichnis 68 7. Anlagen 74 Erklärung über die eigenständige Abfassung der Arbeit 74 Lebenslauf 75 Danksagung 76

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