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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.
31

Towards the development of selective hydrocarbon oxygenation catalysts

Guisado Barrios, Gregorio January 2010 (has links)
The synthesis of pure tris(6-hydroxymethyl-2-pyridylmethyl)amine (H₃L₁₁) is reported for the first time. New complexes of H₃L₁₁ with copper(II), manganese(II) and iron(III) have been characterised by X-ray crystallography. Linear [Fe₃(L₁₁)₂](ClO₄)₃ reveals the tightest Fe-O-Fe angle (87.6°) and shortest Fe...Fe distance (2.834 Å) presently found for a weakly antiferromagnetically-coupled high spin alkoxide-bridged polyiron(III) system. H₃L₁₁ provides a route to various hydrophobic peralkylated TPA ligand derivatives for creating a hydrophobic pocket for the assembly of iron catalysts for the novel 1-hydroxylation of n-alkanes. New 6-py substituted TPA ligands containing methyl (L₁₅) and n-octyl (L₁₆) ether linkages were synthesised via alkylation. Two further novel 6-py substituted ligands were synthesized incorporating n-hexyl substituents on one (L₂₁) and two (L₂₂) of the py moieties. Here a urea spacer group was used to promote hydrogen–bond assisted heterolytic O-O cleavage (generation of the potent FeV=O oxidant) within the hydroxoperoxoiron(III) precursor. High spin [FeII(L)(CH₃CN)[subscript(x)]](CF₃SO₃)₂ complexes (x = 0–2, L = L₁₅,₁₆,₂₁,₂₂) were characterised in solution by ¹H NMR. The structure of [Fe(L₂₂)](CF₃SO₃)₂ reveals a distorted iron(II) centre bound to four N atoms and two urea carbonyls. Iron(II) complexes of H₃L₁₁, L₁₅,₁₆,₂₁,₂₂ and tris(6-Br)-TPA (L₂₄), were investigated for catalysis of the oxygenation of cyclohexane by H₂O₂. Reaction of the iron(II) complexes with H₂O₂ and [superscript(t)]BuOOH was followed by time-resolved EPR and UV-VIS spectrophotometry. A correlation between the observed catalytic activity and the nature of the FeIII(L)-OOR intermediates generated is apparent. A convenient ‘one-pot’ synthesis of benzene-1,3,5-triamido-tris(l-histidine methyl ester) is reported along with attempts at preparing N,N’-bis(pyridylmethyl)-1,3- diaminopropane-2-carboxylic acid (L₂₅), a new water soluble pyridine-amine ligand. The final demetallation step resulted in ligand hydrolysis to the novel amino acid; 1,3-diaminopropane- 2-carboxylic acid which was characterised as its HCl salt by X-ray crystallography.
32

The Na+/H+ exchanger Nhx1 of Saccharomyces cerevisiae is essential to limit drug toxicity

Khodami-Pour, Ali 04 1900 (has links)
Nhx1 est un antiport vacuolaire de Na+/H+ chez la levure Saccharomyces cerevisiae. Nhx1 joue un rôle important dans le maintien de l’homéostasie ionique du cytoplasme de la cellule. En effet, la mutation du gène NHX1 chez la levure nhx1Δ entraîne une perte de l’homéostasie cellulaire quand les cellules sont cultivées dans un milieu de faible osmolarité. Ce travail rapporte pour la première fois, et contrairement à la cellule parentale, que la mutation du gène NHX1 a pour effet une sensibilité du mutant nhx1Δ à une variété des drogues et des agents cationiques et anioniques lorsque les cellules sont cultivées dans un milieu riche. En outre, dans ces conditions de culture, aucune sensibilité n’a été observée chez le mutant nhx1Δ quand les cellules sont traitées avec différentes concentrations de sel. Nous avons aussi démontré que la sensibilité du mutant nhx1Δ aux différents agents ainsi que la sécrétion de l’enzyme carboxypeptidase Y observé chez ce mutant n’ont pas été restauré lorsque les cellules sont cultivées dans des milieux avec différents pH ou avec différentes concentrations de sel. Enfin, une analyse génétique a révélé que le mutant nhx1Δ montre un phénotype distinct d’autres mutants qui ont un défaut dans le trafic entre le compartiment pré-vacuolaire et l’appareil de Golgi quand ces cellules sont traitées avec différents agents. Cette analyse prouve que la sensibilité de nhx1Δ aux différents agents n’est pas liée au trafic entre le compartiment pré-vacuolaire et l’appareil de Golgi. / Nhx1 is an intracellular Na+/H+ exchanger localized to the late endosome in Saccharomyces cerevisiae. It is believed that Nhx1 plays a major role in pH-mediated vesicle trafficking, as nhx1Δ mutant is defective in maintaining the intracellular pH in the vacuoles and cytoplasm when grown in low osmolarity media. In this work, we reported novel drug sensitivities of the nhx1Δ mutant to a range of cationic and anionic agents when cells are grown in rich media. Unlike the low osmolarity media, the nhx1Δ mutant showed no sensitivity to salt. Furthermore, we showed that the drug phenotypes of the nhx1Δ mutant, as well as the secretion of the vacuolar protein carboxypeptidase Y, were not rescued by either altering the pH or salt concentration. Although, amino acid substitution of the phylogenetically conserved residue Glu355 for Ala (E355A) in Nhx1 resulted in sensitivity to genotoxic drug bleomycin, it was not observed for the non-conserved residue Glu371Ala (E371A). Moreover, genetic analysis revealed that the nhx1Δ mutant displayed distinct drug phenotypes in comparison to mutants that are defective in retrograde trafficking from the prevacuole to the late Golgi, excluding the possibility that the drug sensitivity of the nhx1Δ mutant is related to retrograde trafficking.
33

Impact du stress oxydant sur les mécanismes de clairance alvéolaire et de réparation épithéliale pulmonaires

Chupin, Cécile January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
34

Syndrome de détresse respiratoire aiguë (SDRA) : étude de mécanismes impliqués dans la phase exsudative

Chupin, Cécile 08 1900 (has links)
Le syndrome de détresse respiratoire aiguë (SDRA) se développe suite à une atteinte pulmonaire lésionnelle, induisant un œdème et une inflammation excessive, généralement suivis d’une réparation atypique menant à la fibrose. Malgré de signifiants progrès dans les traitements, la mortalité reste élevée : ~ 40 %. Mon hypothèse de travail est que l’atténuation de l’œdème ou de la réponse inflammatoire pourrait freiner le développement ou la sévérité de la phase exsudative. Nous avons évalué cette hypothèse à l’aide d’un modèle de phase exsudative du SDRA, i.e. instillation intra-trachéale de bléomycine, chez les souris.  La modulation des fluides alvéolaires est étudiée avec des souris transgénique (Tg) pour le canal ENaC, qui sont sensibles à la formation d’un œdème. Cependant, ces souris Tg ne sont pas plus sensibles au développement de la phase exsudative en condition lésionnelle (bléomycine). Nous avons déterminé par une étude électrophysiologique des cellules épithéliales alvéolaires de type II (AT II) que ce n’est pas lié à une inhibition par la bléomycine de la fonction du canal ENaC.  Le traitement de la réponse inflammatoire associée au SDRA par des glucocorticoïdes est une thérapie potentielle mais controversée. Les glucocorticoïdes dans notre modèle murin ne réduisent pas la sévérité des lésions. Nous avons pu déterminé lors d’expériences in vitro que ce serait dû à une réduction de la capacité de réparation des AT II. En résumé :  La modulation du canal ENaC ne modifie pas le développement de la phase exsudative, suggérant que la régulation de l’œdème n’est pas suffisante pour modifier l’évolution du SDRA.  La modulation de l’inflammation par les glucocorticoïdes est ineffective, possiblement à cause d’une altération de la réparation. Mon étude suggère que le traitement de la phase exsudative du SDRA est complexe. En effet, la régulation de l’œdème ou de l’inflammation de façon isolée ne peut pas modifier l’évolution du SDRA. L'hétérogénéité des sources du SDRA et la redondance des mécanismes cellulaires impliqués dans l’évolution des lésions pulmonaires suggèrent que le traitement nécessitera une approche visant plusieurs cibles mécanistiques afin d’en accélérer la résolution. / Although much has been learned about the mechanisms leading to acute respiratory distress syndrome (ARDS), mortality remains high: ~ 40%. This syndrome is associated with lung injury where alveolar edema and excessive inflammatory response can progress to abnormal epithelial repair and fibrosis. The hypothesis of the work presented in this thesis is that attenuation of edema or of the inflammatory response in the initial stage of the acute lung injury would decrease the severity of injury. I evaluated this hypothesis in an ARDS acute phase, modeled by an intratracheal instillation of bleomycin in mice, using two distinct experimental strategies.  The importance of edema clearance was studied in a transgenic (Tg) ENaC mouse, a mouse known to be sensitive to the formation of edema. However, our results show that these Tg mice were not more susceptible to the development of the ARDS acute phase induced by bleomycin. Furthermore, we have been able to show that bleomycin itself did not interfere with the ENaC channel function of alveolar epithelial cells type II (AT II).  The treatment of the inflammatory response associated with ARDS by glucocorticoid therapy is subject to controversy. In our mouse model, glucocorticoids decrease the level of cytokine in the alveolar milieu but did not decrease the severity of lung injury. Using in vitro experiments, we show that this lack of response could be secondary to the impact of the treatment on the epithelial repair capacity of AT II. In summary:  The ENaC channel expression did not have an impact on the development of the exudative phase, suggesting that the regulation of edema is not sufficient to alter the course of ARDS.  The modulation of inflammation by glucocorticoids was ineffective, possibly because of impaired repair of the epithelium. These results suggest that the control of edema or inflammation separately does not modify the evolution of lung injury. The heterogeneity of the ARDS origins and the redundancy of cellular mechanisms involved in lung injury will require therapy aimed at multiple pathophysiological targets to permit the resolution of lung injury.
35

Syndrome de détresse respiratoire aiguë (SDRA) : étude de mécanismes impliqués dans la phase exsudative

Chupin, Cécile 08 1900 (has links)
Le syndrome de détresse respiratoire aiguë (SDRA) se développe suite à une atteinte pulmonaire lésionnelle, induisant un œdème et une inflammation excessive, généralement suivis d’une réparation atypique menant à la fibrose. Malgré de signifiants progrès dans les traitements, la mortalité reste élevée : ~ 40 %. Mon hypothèse de travail est que l’atténuation de l’œdème ou de la réponse inflammatoire pourrait freiner le développement ou la sévérité de la phase exsudative. Nous avons évalué cette hypothèse à l’aide d’un modèle de phase exsudative du SDRA, i.e. instillation intra-trachéale de bléomycine, chez les souris.  La modulation des fluides alvéolaires est étudiée avec des souris transgénique (Tg) pour le canal ENaC, qui sont sensibles à la formation d’un œdème. Cependant, ces souris Tg ne sont pas plus sensibles au développement de la phase exsudative en condition lésionnelle (bléomycine). Nous avons déterminé par une étude électrophysiologique des cellules épithéliales alvéolaires de type II (AT II) que ce n’est pas lié à une inhibition par la bléomycine de la fonction du canal ENaC.  Le traitement de la réponse inflammatoire associée au SDRA par des glucocorticoïdes est une thérapie potentielle mais controversée. Les glucocorticoïdes dans notre modèle murin ne réduisent pas la sévérité des lésions. Nous avons pu déterminé lors d’expériences in vitro que ce serait dû à une réduction de la capacité de réparation des AT II. En résumé :  La modulation du canal ENaC ne modifie pas le développement de la phase exsudative, suggérant que la régulation de l’œdème n’est pas suffisante pour modifier l’évolution du SDRA.  La modulation de l’inflammation par les glucocorticoïdes est ineffective, possiblement à cause d’une altération de la réparation. Mon étude suggère que le traitement de la phase exsudative du SDRA est complexe. En effet, la régulation de l’œdème ou de l’inflammation de façon isolée ne peut pas modifier l’évolution du SDRA. L'hétérogénéité des sources du SDRA et la redondance des mécanismes cellulaires impliqués dans l’évolution des lésions pulmonaires suggèrent que le traitement nécessitera une approche visant plusieurs cibles mécanistiques afin d’en accélérer la résolution. / Although much has been learned about the mechanisms leading to acute respiratory distress syndrome (ARDS), mortality remains high: ~ 40%. This syndrome is associated with lung injury where alveolar edema and excessive inflammatory response can progress to abnormal epithelial repair and fibrosis. The hypothesis of the work presented in this thesis is that attenuation of edema or of the inflammatory response in the initial stage of the acute lung injury would decrease the severity of injury. I evaluated this hypothesis in an ARDS acute phase, modeled by an intratracheal instillation of bleomycin in mice, using two distinct experimental strategies.  The importance of edema clearance was studied in a transgenic (Tg) ENaC mouse, a mouse known to be sensitive to the formation of edema. However, our results show that these Tg mice were not more susceptible to the development of the ARDS acute phase induced by bleomycin. Furthermore, we have been able to show that bleomycin itself did not interfere with the ENaC channel function of alveolar epithelial cells type II (AT II).  The treatment of the inflammatory response associated with ARDS by glucocorticoid therapy is subject to controversy. In our mouse model, glucocorticoids decrease the level of cytokine in the alveolar milieu but did not decrease the severity of lung injury. Using in vitro experiments, we show that this lack of response could be secondary to the impact of the treatment on the epithelial repair capacity of AT II. In summary:  The ENaC channel expression did not have an impact on the development of the exudative phase, suggesting that the regulation of edema is not sufficient to alter the course of ARDS.  The modulation of inflammation by glucocorticoids was ineffective, possibly because of impaired repair of the epithelium. These results suggest that the control of edema or inflammation separately does not modify the evolution of lung injury. The heterogeneity of the ARDS origins and the redundancy of cellular mechanisms involved in lung injury will require therapy aimed at multiple pathophysiological targets to permit the resolution of lung injury.
36

The Na+/H+ exchanger Nhx1 of Saccharomyces cerevisiae is essential to limit drug toxicity

Khodami-Pour, Ali 04 1900 (has links)
Nhx1 est un antiport vacuolaire de Na+/H+ chez la levure Saccharomyces cerevisiae. Nhx1 joue un rôle important dans le maintien de l’homéostasie ionique du cytoplasme de la cellule. En effet, la mutation du gène NHX1 chez la levure nhx1Δ entraîne une perte de l’homéostasie cellulaire quand les cellules sont cultivées dans un milieu de faible osmolarité. Ce travail rapporte pour la première fois, et contrairement à la cellule parentale, que la mutation du gène NHX1 a pour effet une sensibilité du mutant nhx1Δ à une variété des drogues et des agents cationiques et anioniques lorsque les cellules sont cultivées dans un milieu riche. En outre, dans ces conditions de culture, aucune sensibilité n’a été observée chez le mutant nhx1Δ quand les cellules sont traitées avec différentes concentrations de sel. Nous avons aussi démontré que la sensibilité du mutant nhx1Δ aux différents agents ainsi que la sécrétion de l’enzyme carboxypeptidase Y observé chez ce mutant n’ont pas été restauré lorsque les cellules sont cultivées dans des milieux avec différents pH ou avec différentes concentrations de sel. Enfin, une analyse génétique a révélé que le mutant nhx1Δ montre un phénotype distinct d’autres mutants qui ont un défaut dans le trafic entre le compartiment pré-vacuolaire et l’appareil de Golgi quand ces cellules sont traitées avec différents agents. Cette analyse prouve que la sensibilité de nhx1Δ aux différents agents n’est pas liée au trafic entre le compartiment pré-vacuolaire et l’appareil de Golgi. / Nhx1 is an intracellular Na+/H+ exchanger localized to the late endosome in Saccharomyces cerevisiae. It is believed that Nhx1 plays a major role in pH-mediated vesicle trafficking, as nhx1Δ mutant is defective in maintaining the intracellular pH in the vacuoles and cytoplasm when grown in low osmolarity media. In this work, we reported novel drug sensitivities of the nhx1Δ mutant to a range of cationic and anionic agents when cells are grown in rich media. Unlike the low osmolarity media, the nhx1Δ mutant showed no sensitivity to salt. Furthermore, we showed that the drug phenotypes of the nhx1Δ mutant, as well as the secretion of the vacuolar protein carboxypeptidase Y, were not rescued by either altering the pH or salt concentration. Although, amino acid substitution of the phylogenetically conserved residue Glu355 for Ala (E355A) in Nhx1 resulted in sensitivity to genotoxic drug bleomycin, it was not observed for the non-conserved residue Glu371Ala (E371A). Moreover, genetic analysis revealed that the nhx1Δ mutant displayed distinct drug phenotypes in comparison to mutants that are defective in retrograde trafficking from the prevacuole to the late Golgi, excluding the possibility that the drug sensitivity of the nhx1Δ mutant is related to retrograde trafficking.
37

Impact du stress oxydant sur les mécanismes de clairance alvéolaire et de réparation épithéliale pulmonaires

Chupin, Cécile January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
38

The role of directed gp130-mediated signalling in bleomycin-induced murine pulmonary fibrosis

O'Donoghue, Robert Joseph James January 2008 (has links)
[Truncated abstract] Fibrosis is a feature of many pulmonary conditions, including idiopathic pulmonary fibrosis (IPF), which is characterised by the accumulation of fibroblasts/myofibroblasts and excessive deposition of collagen. IPF is a disease of unknown aetiology that is unresponsive to current therapy and is typically fatal. The inflammatory cytokine interleukin (IL)-6 is elevated in patients with IPF and recent studies have shown that IL-6-induced signalling is altered in lung fibroblasts from patients with IPF. IL-6 belongs to the gp130 cytokine family, which is a group of ten structurally related cytokines, that all require the membrane bound glycoprotein gp130 to activate intracellular signalling pathways. Gp130 activates intracellular signalling through the Shp2-ERK1/2 and STAT1/3 pathways to mediate cellular activities. This thesis tests the hypothesis that gp130-mediated signalling is dysregulated in the development and progression of pulmonary fibrosis. To address this hypothesis, I assessed the role of gp130-mediated signalling in a mouse model of bleomycin-induced lung fibrosis. This thesis utilised two novel gp130 mutant mice strains with directed and enhanced gp130-mediated Shp2-ERK1/2 (gp130¿STAT/¿STAT) or STAT1/3 (gp130757F/757F) signalling. I observed complete protection from fibrosis in gp130¿STAT/¿STAT mice up to 60 days after bleomycin treatment and profound fibrosis in gp130757F/757F mice compared to wt controls. The enhanced fibrosis observed in gp130757F/757F mice was diminished by monoallelic deletion of STAT3 (gp130757F/757F;STAT3+/-), identifying gp130-STAT3 signalling as a novel promoter of lung fibrosis. ... In addition, IL-6/11 activation of gp130-mediated signalling modulated transforming growth factor (TGF)-ß-induced effects on adult fibroblast proliferation and myofibroblast differentiation. Interaction between IL-6/11 and TGF-ß1 on fibroblast proliferation was dependent on both the gp130-ERK1/2 and gp130-STAT1/3 pathways. Loss of either pathway abrogated the effects of IL-6 and IL-11 on TGF-ß1- 4 induced fibroblast proliferation. However, it was clear that gp130-STAT3 signalling inhibited TGF-ß1-induced myofibroblast differentiation of primary lung fibroblasts. The inhibition of myofibroblast differentiation was associated with gp130-STAT3 dependent inhibition of TGF-ß1-induced Smad3 phosphorylation. These results indicate that IL-6 and IL-11 promote myofibroblastic differentiation of lung fibroblasts, while gp130-STAT3 signalling inhibits TGF-ß1-induced Smad3 phosphorylation and myofibroblastic differentiation of lung fibroblasts While the pathogenesis of IPF is unknown, it is believed that excessive collagen deposition, aberrant fibroblast behaviour and an inflammatory response are critical to the progression of this disease. It has been shown here that IL-6 family cytokines mediate the development and progression of bleomycin-induced lung fibrosis by increasing collagen synthesis, fibroblast proliferation, myofibroblast differentiation and inflammation through gp130-STAT3 signalling. This thesis has demonstrated that differential activation of cytoplasmic signalling pathways by a membrane bound receptor can have a profound effect on pulmonary responses to injury. Furthermore, this thesis is the first study to identify the gp130-STAT3 pathway as a therapeutic target in the treatment of IPF.
39

Influência do desequilíbrio redox e resposta inflamatória na fibrose pulmonar associada a estímulo inflamatório prévio / Influence of redox imbalance and inflammatory response in pulmonary fibrosis associated with inflammatory stimuli

Larissa Alexsandra da Silva Neto Trajano 17 September 2013 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / A fibrose pulmonar é uma doença pulmonar crônica caracterizada pelo acúmulo excessivo de matriz extracelular (MEC) e um remodelamento na arquitetura pulmonar. Embora já se saiba da participação do estresse oxidativo e da inflamação na fibrose de forma isolada, é importante observar como se comporta o estresse oxidativo na fibrose quando esta ocorre associada a uma doença de base. O presente estudo teve como objetivo investigar o perfil inflamatório e oxidativo na fibrose pulmonar associado ao enfisema pulmonar prévio. Camundongos C57BL/6 foram divididos em três grupos: grupo controle (n=5) que receberam salina intranasal (50 l) e foram sacrificados no 21 dia; grupo bleomicina (BLEO) (n=15) que receberam bleomicina intratraqueal (0.1 U/animal) no dia 0 e foram sacrificados nos 7 (n=5), 14 (n=5) e 21 (n=5) dias e grupo PPE (elastase) + BLEO (n=21) que receberam elastase (3U/animal) e após 14 dias receberam bleomicina e foram sacrificados nos 14(n=7), 21 (n=7), 28 (n=7) e 35 (n=7) dias. Foram realizadas análises histológicas através de H&E e picro-sirius; análises bioquímicas para superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx) e glutationa-S-transferase (GST) e ELISA para Interleucina (IL)-1&#946; e IL-6. A fibrose pulmonar ocorreu a partir do 14 dia (p<0.001) e o enfisema concomitante a fibrose pulmonar a partir do 28 dia (p<0.001) e um aumento de fibras colágenas no grupo BLEO 21(p<0.001) e PPE + BLEO 21(p<0.001). As enzimas antioxidantes CAT (p<0.01), SOD (p<0.01) e GPx (p<0.01) reduziram e a GST aumentou no grupo BLEO 21 dias (p<0.05). No grupo PPE + BLEO 21 dias houve redução das enzimas antioxidantes CAT, SOD, GPx (p<0.05) e GST. Os níveis de óxido foram altos nos grupos BLEO 21 dias (p<0.01) e PPE + BLEO 21 dias (p<0.01). A IL-1&#946; mostrou-se elevada no grupo BLEO 7 dias quando comparado ao controle (p<0.001) e ao grupo PPE + BLEO 7 dias (p<0.01). Concluímos que a resposta inflamatória inibiu a ação do sistema antioxidante contribuindo para o agravamento da lesão. Isso sugere que terapias anti-inflamatórias podem contribuir tanto para redução da resposta inflamatória quanto de forma indireta no sistema antioxidante. / Pulmonary fibrosis (PF) is a chronic lung disease characterized by excessive accumulation of extracellular matrix (ECM) and remodeling in the lung architecture. Although it is already known the role of oxidative stress and inflammation in the isolated pulmonary fibrosis, it is important to observe how it behaves oxidative stress in pulmonary fibrosis when it occurs associated with an underlying disease. The present study aimed to investigate the inflammatory status and oxidative pulmonary fibrosis associated with pulmonary emphysema prior. C57BL / 6 mice were divided into three groups: control group (n = 5) who received intranasal saline (50l) and were sacrificed at 21 days, bleomycin (BLEO) group (n=15) who received intratracheal bleomycin (0.1U/animal) in the day 0 and were sacrificed at 7 (n=5), 14 (n=5) and 21 (n=5) days and the PPE + BLEO group (n=21) received elastase (PPE)(3U/animals) and 14 days after receiving bleomycin and were sacrificed at 14 (n = 7), 21 (n = 7) 28 (n = 7) and 35 (n = 7) days. Histological analysis was achieved using H&E and Sirius red staining; biochemical analysis for superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) and ELISA for IL-1&#946; and IL-6 were conducted. Pulmonary fibrosis occurred from day 14 (p<0.001) emphysema and pulmonary fibrosis from day 28 (p <0.001) and occurred an increase of collagen fibers in the BLEO group 21days (p<0.001) and PPE + BLEO 21days (p <0.001). Antioxidant enzymes CAT (p <0.01), SOD (p <0.01), and GPx (p <0.01) were reduced and GST increased in the BLEO group 21 days (p<0,05). In the PPE + BLEO group 21 days occurred an decreased antioxidant enzymes CAT, SOD, GPx (p <0.05), and GST. Oxide levels were higher in the BLEO groups 21 days (p <0.01), and PPE + BLEO group 21 days (p <0:01). IL-1&#946; was elevated in the group BLEO 7 days when compared to control (p <0.001) and the PPE + BLEO group 7 days (p<0.01). The inflammatory response inhibited the action of the antioxidant system contributes to the aggravation of the injury. This suggests that anti-inflammatory therapies may contribute to reducing the inflammatory response as indirectly to the antioxidant system.
40

Influência do desequilíbrio redox e resposta inflamatória na fibrose pulmonar associada a estímulo inflamatório prévio / Influence of redox imbalance and inflammatory response in pulmonary fibrosis associated with inflammatory stimuli

Larissa Alexsandra da Silva Neto Trajano 17 September 2013 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / A fibrose pulmonar é uma doença pulmonar crônica caracterizada pelo acúmulo excessivo de matriz extracelular (MEC) e um remodelamento na arquitetura pulmonar. Embora já se saiba da participação do estresse oxidativo e da inflamação na fibrose de forma isolada, é importante observar como se comporta o estresse oxidativo na fibrose quando esta ocorre associada a uma doença de base. O presente estudo teve como objetivo investigar o perfil inflamatório e oxidativo na fibrose pulmonar associado ao enfisema pulmonar prévio. Camundongos C57BL/6 foram divididos em três grupos: grupo controle (n=5) que receberam salina intranasal (50 l) e foram sacrificados no 21 dia; grupo bleomicina (BLEO) (n=15) que receberam bleomicina intratraqueal (0.1 U/animal) no dia 0 e foram sacrificados nos 7 (n=5), 14 (n=5) e 21 (n=5) dias e grupo PPE (elastase) + BLEO (n=21) que receberam elastase (3U/animal) e após 14 dias receberam bleomicina e foram sacrificados nos 14(n=7), 21 (n=7), 28 (n=7) e 35 (n=7) dias. Foram realizadas análises histológicas através de H&E e picro-sirius; análises bioquímicas para superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx) e glutationa-S-transferase (GST) e ELISA para Interleucina (IL)-1&#946; e IL-6. A fibrose pulmonar ocorreu a partir do 14 dia (p<0.001) e o enfisema concomitante a fibrose pulmonar a partir do 28 dia (p<0.001) e um aumento de fibras colágenas no grupo BLEO 21(p<0.001) e PPE + BLEO 21(p<0.001). As enzimas antioxidantes CAT (p<0.01), SOD (p<0.01) e GPx (p<0.01) reduziram e a GST aumentou no grupo BLEO 21 dias (p<0.05). No grupo PPE + BLEO 21 dias houve redução das enzimas antioxidantes CAT, SOD, GPx (p<0.05) e GST. Os níveis de óxido foram altos nos grupos BLEO 21 dias (p<0.01) e PPE + BLEO 21 dias (p<0.01). A IL-1&#946; mostrou-se elevada no grupo BLEO 7 dias quando comparado ao controle (p<0.001) e ao grupo PPE + BLEO 7 dias (p<0.01). Concluímos que a resposta inflamatória inibiu a ação do sistema antioxidante contribuindo para o agravamento da lesão. Isso sugere que terapias anti-inflamatórias podem contribuir tanto para redução da resposta inflamatória quanto de forma indireta no sistema antioxidante. / Pulmonary fibrosis (PF) is a chronic lung disease characterized by excessive accumulation of extracellular matrix (ECM) and remodeling in the lung architecture. Although it is already known the role of oxidative stress and inflammation in the isolated pulmonary fibrosis, it is important to observe how it behaves oxidative stress in pulmonary fibrosis when it occurs associated with an underlying disease. The present study aimed to investigate the inflammatory status and oxidative pulmonary fibrosis associated with pulmonary emphysema prior. C57BL / 6 mice were divided into three groups: control group (n = 5) who received intranasal saline (50l) and were sacrificed at 21 days, bleomycin (BLEO) group (n=15) who received intratracheal bleomycin (0.1U/animal) in the day 0 and were sacrificed at 7 (n=5), 14 (n=5) and 21 (n=5) days and the PPE + BLEO group (n=21) received elastase (PPE)(3U/animals) and 14 days after receiving bleomycin and were sacrificed at 14 (n = 7), 21 (n = 7) 28 (n = 7) and 35 (n = 7) days. Histological analysis was achieved using H&E and Sirius red staining; biochemical analysis for superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) and ELISA for IL-1&#946; and IL-6 were conducted. Pulmonary fibrosis occurred from day 14 (p<0.001) emphysema and pulmonary fibrosis from day 28 (p <0.001) and occurred an increase of collagen fibers in the BLEO group 21days (p<0.001) and PPE + BLEO 21days (p <0.001). Antioxidant enzymes CAT (p <0.01), SOD (p <0.01), and GPx (p <0.01) were reduced and GST increased in the BLEO group 21 days (p<0,05). In the PPE + BLEO group 21 days occurred an decreased antioxidant enzymes CAT, SOD, GPx (p <0.05), and GST. Oxide levels were higher in the BLEO groups 21 days (p <0.01), and PPE + BLEO group 21 days (p <0:01). IL-1&#946; was elevated in the group BLEO 7 days when compared to control (p <0.001) and the PPE + BLEO group 7 days (p<0.01). The inflammatory response inhibited the action of the antioxidant system contributes to the aggravation of the injury. This suggests that anti-inflammatory therapies may contribute to reducing the inflammatory response as indirectly to the antioxidant system.

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