Due to the intrauterine environment required to maintain pregnancy it may be that neonatal animals are born type-2 immune response (IR) biased, which consequently may increase susceptibility to certain infectious and immune mediated diseases, such as allergy. Recently, the prevalence of both allergic and autoimmune diseases has increased, leading to the development of the hygiene hypothesis. The hypothesis states that lack of early environmental stimulus leading to inappropriate development and bias in IR, may contribute to this increase. The objectives of this thesis, therefore, were to: (a) Determine the IR bias of neonatal pigs. (b) Investigate the effect of heat-killed Escherichia coli, lipopolysaccharide (LPS) and muramyl dipeptide (MDP) on the IR phenotype and the frequency of allergy in pigs sensitized to the egg white allergen ovomucoid (Ovm). (c) Establish IR phenotypes of pigs allergic or clinically tolerant to Ovm. Immune response bias was determined using an established phenotyping protocol and compared between two groups of pigs, (A) and (B). A difference in IR bias was observed. Bias in IR was not consistently towards type-2. Increase in indicators of type-1 IR, were greater in A and the frequency of type-2 IR correlates were greater in B. It’s likely that unidentified environmental variables may have induced this change, although etiology was not pursued. Treatment with heat-killed Escherichia coli, LPS and MDP had an effect on IR bias and frequency of allergy. Muramyl dipeptide-treatments promoted type-2 bias and were associated with increased frequency of allergy. Pre-treatment with E. coli did not affect allergic frequency, but did elicit the production of a relatively balanced allergen-specific IR phenotype. Lipopolysaccharide-pre-treatment was associated with decreased frequency of allergy. Correlates of an allergic IR phenotype in pigs were also established. The measurement of allergen-specific IgG, IgG1 and/or IgE activity and evaluation of late-phase intradermal skin tests were proposed to be useful in identifying allergic IR phenotypes. This thesis emphasizes the importance of considering the potential for variation in IR in terms of pig health and experimental reproducibility. Further, given the physiological similarities of pigs and humans, these findings may be extended to studies of food allergy in humans. / NSERC, OMAFRA, Ontario Pork, AllerGen NCE

Comme à l’approche d’un tsunami, l’incidence grandissante des allergies affecte maintenant plus de 30% de la population des pays développés. Étant la cause de nombreuses morbidités et un risque significatif de mortalité, les allergies nécessitent des dépenses exorbitantes au système de santé et constituent une des plus importantes sources d’invalidité. Cette thèse a pour but de contribuer à faciliter la prise de décision éclairée dans le développement de politiques en santé en lien avec cette maladie immunitaire chronique en utilisant des principes d’éthique comme outils pour guider le développement de politiques en santé. Le premier chapitre démontre le présent déficit d’analyses des enjeux éthiques en allergologie et démontre de quelle façon les réflexions en éthique peuvent guider le développement de politiques et l’élaboration de stratégies appliquées aux allergies. Les chapitres qui suivront présentent des applications spécifiques des principes d’éthiques ciblant des contextes précis comme des méthodes qui fournissent des outils de réflexion et des cadres théoriques qui peuvent être appliqués par les décideurs pour guider des interventions en santé concernant les allergies et les conditions de co-morbidité reliées. Le second chapitre présente un cadre théorique pour l’évaluation et la priorisation d’interventions en santé publique par la diminution des allergènes présents dans l’environnement basées sur des théories de justice sociale. Les critères entourant les politiques d’évaluation se concentrent sur les enjeux éthiques référant aux populations vulnérables, sur une distribution plus égale des bénéfices pour la santé, et sur le devoir d’éviter la stigmatisation. Le troisième chapitre offre aux administrateurs et au personnel infirmier du réseau scolaire un cadre décisionnel pour guider le développement de politiques efficaces et éthiquement justifiables concernant les allergies alimentaires pour les écoles. Dans ce contexte, les principes de base d’éthique en santé publique et en bioéthique - par exemple, l’empowerment des populations vulnérables dans la prise en charge de leur santé et la protection de la confidentialité du dossier médical - servent d’outils pour évaluer les politiques. Le dernier chapitre emploie les principes de base de recherche en éthique comme méthode pour développer un argumentaire en faveur de la réforme des réglementations entourant la production de médicaments immunothérapeutiques. La nécessité éthique d’éviter les risques de méfait à l’endroit du sujet humain dans la recherche permettra de servir de guide pour structurer de futures politiques en santé publique en égard à la production d’immunothérapeutiques à l’échelle mondiale. / Like a slowly rising wave approaching shore, the growing incidence of allergic disease now afflicts over 30% of the population in the developed world. Being the cause of severe morbidities and a significant risk of mortality, allergy requires huge resource expenditures in health care and is a leading cause of disability. This thesis aims to contribute to ameliorating decision-making capacities in health policy development for this chronic immune disease by employing principles of ethics as tools to help structure policy initiatives. The first chapter will demonstrate the current deficiency of ethical analysis in allergology and show how ethical assessments could have utility in guiding policy developments and treatment strategies for allergy. The subsequent chapters present a focused application of ethical principles within specific contexts as a means to provide reflective tools and theoretical frameworks that could be used by decision-makers to guide health interventions for allergy and co-morbid conditions. The second chapter presents a conceptual framework for evaluating and prioritizing public health interventions in minimizing environmental allergens based on theories of social justice. Policy assessment criteria centre on justice issues pertaining to vulnerable populations, the fair distribution of health benefits, and the imperative to avoid stigma. The third chapter provides school administrators with a framework to guide the development of efficacious and ethically sound food allergy policies for schools. In this context, core principles in public health ethics and bioethics – examples being the empowerment of vulnerable populations in controlling their health and protecting confidentiality of medical information – serve as tools for policy assessments. The final chapter employs core principles from research ethics as a method to argue for regulatory reforms in the production of allergenimmunotherapeutic drugs. The ethical imperative to avoid risks of harm to human subjects in research will serve as a guide to structure future health policies in the global production of immuno-therapeutics.

Interleukin-10 (IL-10) is an important regulator of immune responses secreted by different cell types. Previous results from our group suggested that the biological effects of this cytokine critically depend on its cellular source. Recent studies reported IL-10 dependent immunosuppressive functions of a specialized subset of regulatory B cells and mast cells. These results relied on adoptive cell transfers, a technique which can potentially introduce artifacts. Therefore, we aimed to readdress these questions in independent models using IL-10 transcriptional reporter mice and various conditional IL-10 mutant mice. Findings in IL-10 reporter system suggested prominent IL-10 transcription in regulatory B cells upon LPS administration. Exposure of mice to contact allergen revealed robust reporter expression in CD8 T cells, moderate to mild reporter expression in CD4 T cells and dendritic cells (DC) respectively, and lack of reporter expression in B cells, mast cells and NK cells in allergen challenged ears. We generated cell-type specific IL-10 mutants by Cre/LoxP-mediated conditional gene inactivation. Efficiency and specificity of Cre-mediated recombination was demonstrated by Southern blot and PCR methods. Various immunogenic challenges in conditional IL-10 mutants did not reveal a role for B cell-derived IL-10 in restraining innate TLR or T cell-dependent inflammatory responses. Likewise, mice with selective inactivation of the il10 gene in mast cells exhibited normal CHS responses and unaltered immune response to CpG oligodeoxynucleotides. On the other hand, DC-specific IL-10 mutants developed excessive inflammatory responses to contact allergens, while innate responses to TLR ligands were not altered. This indicates a non-redundant role for DC-derived IL-10 in contact allergy. Thus, the conditional IL-10 ‘‘knockout’’ mice combined with the novel transcriptional IL-10 reporter system can serve as ideal tools to understand the cell-type specific contributions to IL-10-mediated immune regulation.

No description available.

No description available.

Les nanoparticules (NPs) organiques représentent un outil majeur d'innovation en dermatologie. L'objectif de cette thèse a été de développer et d'optimiser des procédés d'encapsulation d'un mélange de molécules odorantes appelé fragrance mix I (FMI) dans des nanoparticules (NPs) de différentes natures: NPs polymères (poly-ε-caprolactone, PCL), ou NPs lipidiques solides (SLNs) (à base de vaseline, beurre de karité, cire de candelilla, triglycérides C10-18, ou palmitate de cétyle). Ces nouveaux systèmes ont alors été évalués pour la vectorisation de ce mélange à travers un explant de peau de porc, afin de modéliser la distribution des molécules composant le FMI dans les différentes assises cutanées. En parallèle, elles ont également été appliquées en tant que promoteurs de solubilisation du FMI pour le développement d'un nouveau test de diagnostic in vitro de l'allergie aux parfums. Nos résultats montrent que: (i) les NPs polymères, principalement anioniques, sont les plus adaptées pour promouvoir la pénétration transépidermique du FMI. Au contraire, les SLNs s'agglomèrent dans le stratum corneum, conduisant à une accumulation du FMI dans cette assise ; (ii) qu'au-delà du type de vecteur utilisé, la pénétration des molécules du FMI dans les couches les plus profondes de la peau dépend de leur coefficient de partage intrinsèque ; (iii) que les nanoparticules de PCL augmentent significativement la solubilisation du FMI dans les milieux de culture conventionnels et permettent ainsi une réactivation robuste des lymphocytes T spécifiques circulant chez des patients présentant une allergie au parfums. L'ensemble de ces résultats confirme donc tout le potentiel des NPs organiques pour le développement de futures stratégies de délivrance ciblée de plusieurs actifs dans les différents compartiments cutanés. Ces nouveaux vecteurs offrent en outre une alternative prometteuse pour améliorer le diagnostic de l'eczéma de contact induit par les parfums et plus généralement par des allergènes hydrophobes / The aim of this work was to develop and optimize methods for fragrance mix I (FMI) encapsulation into nanoparticles (NPs) of two types of nanoparticles (NPs) : polymeric NPs (poly-ε-caprolactone, PCL) and solid lipid NPs (SLNs) (prepared with petrolatum, shea butter, candelilla wax, C10-18 triglycerides, or cetyl palmitate). Then, these new NPss were evaluated as vectors through a pig skin to analyze the distribution of the FMI molecules in the different skin layers. In parallel, NPs have also been applied as solubilizers for the development of a new in vitro test for the diagnosis of fragrance allergy. Our results show that (i) NPs polymers, mainly anionic NPs, are the most suitable vectors to promote trans-epidermal penetration of fragrance. On the contrary, SLNs were found in the stratum corneum, leading to an accumulation of fragrance in this layer; (ii) whatever the type of NPs, the penetration of the FMI molecules in the deeper layers of the skin depends on their intrinsic partition coefficient; (iii) PCL-NPs significantly increase the FMI solubilization in conventional culture media and, allowing a robust reactivation of circulating specific T cells in patients with allergy to fragrances. All of these results confirm the potential of organic NPs for the development of future strategies (for the skin delivery of several actives in the different skin layers). These new vectors further offer a promising alternative to improve the diagnosis of contact dermatitis induced by fragrances and more generally by hydrophobic allergens

INTRODUÇÃO: A rinite alérgica é uma condição clínica comum que apresenta sintomas diversos num significante número de pacientes, deteriorando a qualidade de vida daqueles refratários aos tratamentos usuais (anti-histamínicos e corticosteróides nasais tópicos). Apresentando princípios curativos similares, a imunoterapia sublingual e a homeopatia podem reduzir os sintomas e a necessidade de medicamentos na rinite alérgica, embora a eficácia e a efetividade de ambas terapêuticas não sejam ainda suficientemente conhecidas. OBJETIVOS: O objetivo deste estudo foi avaliar a efetividade clínica do tratamento homeopático individualizado prolongado, comparativamente ao placebo, em adultos portadores de rinite alérgica perene. MÉTODOS: Um total de 41 pacientes com rinite alérgica perene foi alocado numa primeira fase duplo-cego e placebo-controlada durante seis meses, sendo tratada com doses sublinguais semanais de medicamentos homeopáticos individualizados ou placebo. Após esta fase inicial fechada, todos os pacientes foram convidados a participar de uma segunda fase controlada aberta, em que receberiam tratamento homeopático pelo período máximo de 36 meses, e os resultados foram comparados com a melhora da fase inicial. O escore dos sinais e sintomas, a necessidade de medicamentos de resgate e a qualidade de vida foram mensurados por questionários e avaliações clínicas pessoais, aplicadas por um mesmo avaliador independente, antes e após cada fase. As doses dos medicamentos homeopáticos e de resgate utilizados, assim como os efeitos colaterais, foram documentados num diário pessoal. Os desfechos clínicos primário e secundários foram, respectivamente, os escores dos sinais e sintomas alérgicos específicos e gerais. Títulos da IgE total foram mensurados antes e após cada fase. RESULTADOS: Após os seis meses da fase placebo-controlada inicial, na análise por protocolo de todos os pacientes incluídos no estudo, não foram observadas diferenças significativas entre os grupos ativo e placebo nos escores clínicos, na utilização de drogas de resgate, na qualidade de vida e nos títulos da IgE total. Entretanto, as análises dos subgrupos da segunda fase mostraram uma crescente e significativa melhora nos desfechos clínicos primário e secundários após 12 meses de tratamento homeopático individualizado, comparativamente à variação de melhora dos mesmos pacientes na fase inicial fechada. Diferença significativa na qualidade de vida foi observada apenas após o segundo ano de tratamento homeopático. CONCLUSÃO: Neste estudo, o tratamento homeopático foi acompanhado de um significante efeito placebo. A efetividade da homeopatia pôde ser observada após 12 meses da terapêutica, apresentando efeito preventivo de longa duração após 36 meses de tratamento homeopático individualizado. / INTRODUCTION: Allergic rhinitis is a common clinical condition which presented several symptoms in a significant number of patients, deteriorating the quality of life in those resistant to the usual treatments (antihistamines and topical nasal corticosteroids). Presenting similar curative principles, sublingual immunotherapy and homeopathy can reduce symptoms and medication requirements in allergic rhinitis, although the efficacy and effectiveness of both therapeutics are not still sufficiently known. OBJECTIVES: The objective of this study was to evaluate clinical effectiveness of prolonged individualized homeopathic treatment, compared with placebo, in adults with perennial allergic rhinitis. METHODS: A total of 41 adults with perennial allergic rhinitis were enrolled in a first double-blind placebo-controlled phase for six months, and treated on a weekly basis with sublingual doses of single individualized homeopathic medicines or placebo. After this closed initial phase, all patients were invited to participate in an open label controlled phase, in that they would receive homeopathic treatment for the maximum period of 36 months, and the results were compared with the improvement of the initial phase. Signs and symptoms scores, rescue medication requirements and quality of life were assessed by questionnaires and personal clinical evaluation by a same independent researcher, before and after each phase. Applied homeopathic and rescue drugs dosage, and side effects were documented by diary cards. Primary and secondary clinical outcome were, respectively, specific and general allergic signs and symptoms scores. Total IgE titles were performed before and after each phase. RESULTS: After six months of placebo-controlled phase, analyzing all patients included in the study per protocol, we observed no significant difference between treatment and placebo groups in primary and secondary clinical outcomes, use of rescue drugs, quality of life and total IgE. However, second phase subgroups analysis showed a significant and growing improvement of clinical symptoms after 12 months of individualized homeopathic treatment, comparatively to the same patients\' variation in closed initial phase. Significant difference in quality of life score were observed only after second homeopathic treatment year. CONCLUSION: In this study, homeopathic treatment was accompanied by a significant placebo effect. Effectiveness of homeopathy could be seen after 12 months of therapy, presenting preventive effect of long duration after 36 months of individualized homeopathic treatment.

A prevalência de sintomas de asma, broncoespasmo induzido pelo exercício (BIE), hiperresponsividade brônquica (HRB) e alergia em atletas que praticam modalidades de alto rendimento e longa duração tem aumentado nas últimas décadas e tem sido estudada principalmente em atletas de inverno e nadadores. No entanto, a prevalência de sintomas de asma e alergia e os mecanismos inflamatórios envolvidos no BIE que ocorre em corredores de longa distância permanecem pouco conhecidos. Objetivos: O presente estudo tem como objetivo avaliar a prevalência de sintomas de asma e alergia em corredores de longa distância de elite e investigar os mecanismos inflamatórios envolvidos no BIE nos atletas sem histórico de asma. Casuística e Métodos: Este estudo foi realizado em duas fases: na Fase I, foi avaliada a prevalência de sintomas de asma e alergia em 201 corredores de longa distância, através da aplicação dos questionários ISAAC e AQUA©. Na Fase II, foram avaliados os mecanismos inflamatórios envolvidos no BIE de 40 corredores que não apresentaram sintomas de asma na Fase I e que foram selecionados aleatoriamente. Nesta fase, os atletas compareceram ao laboratório em três momentos, com intervalo máximo de duas semanas entre cada visita, e foram submetidos às seguintes avaliações 1º) escarro induzido e teste cardiopulmonar máximo, 2º) broncoprovocação por metacolina e, 3º) óxido nítrico no ar exalado (FeNO), metabólitos LTE4 e 9alfa, 11beta-PGF2 e teste de hiperventilação eucápnica voluntária (HEV). Resultados: A prevalência de sintomas de asma e alergia foi de 6,5% e 60,5%, respectivamente. Ao analisar as questões do AQUA©, observou-se alta frequência de sintomas de BIE (62,3%) e rinite (56,6%). Os sintomas de alergia não foram associados a variáveis como gênero, idade, experiência em corridas de longa distância, volume de treinamento semanal e desempenho em provas de meia maratona e maratona. Verificou-se ainda que a prevalência de BIE foi de 27,5%. Quando comparados os atletas BIE+ e BIE- não foram observadas diferenças nos valores de VEF1 absoluto, nas medidas antropométricas, nas características de treinamento e também no desempenho. Os atletas BIE+ relataram mais sintomas de alergia (p=0,03), se mostraram mais responsivos à metacolina (p=0,01), apresentaram maior porcentagem de eosinófilos no escarro (p=0,03) e níveis mais elevados de FeNO (p < 0,001*) quando comparados aos atletas BIE-. Os níveis urinários de LTE4 e 9alfa, 11beta-PGF2 basais e após 60 minutos do teste de HEV foram similares entre os grupos BIE+ e BIE-, no entanto, ao comparar os níveis destes mediadores antes e após o teste de HEV, observou-se uma diminuição nos níveis de LTE4, apenas nos atletas BIE- (p=0,04). Conclusões: Corredores de longa distância apresentam elevada prevalência de sintomas de alergia e BIE e baixa prevalência de sintomas de asma. Além disto, os atletas BIE+ referem mais sintomas de alergia, são mais hiperresponsivos à metacolina, apresentam um padrão inflamatório eosinofílico e elevados níveis de FeNO embora sem diferenças nos níveis basais dos metabólitos do mastócito / An increased prevalence of asthma and allergic symptoms, exercise-induced bronchoconstriction (EIB) and bronchial hyperresponsiveness (BHR) has been observed in elite and endurance athletes, especially winter sports athletes and swimmers. However, the occurrence of allergy symptoms and the inflammatory mechanisms involved in the EIB that occurs in long distance runners remains poorly known. Objectives: the aims of the present study were to assess the prevalence of symptoms of asthma and allergy in long distance runners and to investigate possible inflammatory mediators involved in the EIB that occurs in those without asthma history. Methods: This cross sectional study was performed in two phases. In Phase I, the prevalence of symptoms of asthma and allergy was assessed in 201 long distance runners using ISAAC and AQUA© questionnaires. In Phase II, 40 athletes were randomly selected among those who did not present asthma history and they performed the following measurements: induced sputum, cardiopulmonary exercise testing, methacholine bronchoprovocation challenge, exhaled nitric oxide (FeNO), urinary collection to quantify LTE4 and 9alfa, 11beta-PGF2 metabolites and eucapnic voluntary hyperventilation test (EVH). Results: The prevalence of asthma and allergy symptoms was 6.5% and 60.5%, respectively. In addition, we observed a high frequency of EIB symptoms (62.3%) and rhinitis (56.6%). Allergy symptoms were not associated with anthropometric characteristics, running experience, weekly training volume and best half-marathon and marathon performance. The prevalence of EIB was 27.5% and no difference in baseline lung function, anthropometric data as well as training and performance characteristics was observed between athletes with (EIB+) and without (EIB-) EIB. EIB+ athletes reported more allergy symptoms (p=0.03) and were more resposive to methacholine (p=0.01) than EIB- athletes. A higher percentage of eosinophils in the induced sputum (p=0.03) and levels of FeNO (p < 0.001*) were observed in EIB+ athletes. However, there was no difference in the urinary levels of LTE4 and 9alfa, 11beta-PGF2 either at baseline or after EVH test. Conclusions: Long distance runners have a high prevalence of allergy symptoms and EIB and a low prevalence of asthma symptoms. Moreover, EIB+ athletes report more symptoms of allergy and present airway hyperresponsiveness, eosinophilic inflammation and increased levels of exhaled nitric oxide, without difference in the baseline levels of mast cell metabolites

INTRODUÇÃO: A importância da resposta mecânica do parênquima pulmonar na fisiopatologia da asma tem sido recentemente reconhecida. O óxido nítrico é um mediador que controla o tônus muscular liso das vias aéreas, porém este efeito no parênquima pulmonar periférico ainda não foi previamente investigado. Nossa hipótese é que a inibição crônica das óxido nítrico sintases por meio do tratamento com L-NAME (falso substrato para todas as óxido nítrico sintases) pode modular a mecânica do parênquima pulmonar, o recrutamento eosinofílico e o remodelamento da matriz extracelular em modelo de inflamação alérgica crônica pulmonar em cobaias. MÉTODOS: Os animais foram expostos a sete inalações com soro fisiológico ou com ovoalbumina em doses crescentes (1~5mg/ml - 4 semanas) e tratadas ou não com L-NAME (60 mg/kg/ por dia /por animal) na água de beber. Setenta e duas horas após a sétima inalação os animais foram anestesiados, exsanguinados e a mecânica oscilatória do parênquima pulmonar foi medida na condição pré e após desafio (0.1%). Utilizando a técnica de morfometria foram avaliadas a densidade de eosinófilos, o número de células nNOS e iNOS positivas, a densidade de actina, das fibras colágenas e das fibras elásticas bem como a proporção de volume de 8-iso-PGF2 no septo alveolar. RESULTADOS: Os animais que foram expostos à ovoalbumina apresentaram um aumento da resistência e da elastância tecidual (resposta basal e após desafio antigênico), na densidade de eosinófilos, no número de células nNOS e iNOS positivas, na densidade de fibras colágenas e de fibras elásticas bem como na expressão de 8-isoPGF2 no septo alveolar comparativamente aos grupos controles (p<0,05). O tratamento com L-NAME em animais expostos à ovoalbumina atenuou todas as respostas de mecânica do tecido pulmonar periférico (p<0, 01), reduziu o número de células nNOS e iNOS positivas (p<0.01), o conteúdo de fibras elásticas (p<0,001) e de 8-iso-PGF2 no septo alveolar (p<0,001). No entanto, este tratamento não afetou o número total de eosinófilos e o conteúdo de fibras colágenas. Este trabalho sugere que o óxido nítrico contribui para a constrição do parênquima pulmonar e para a deposição de fibras elásticas neste modelo. Estes efeitos foram associados à ativação de iNOS e nNOS em células do parênquima distal e aumento na via do estresse oxidativo / The importance of lung tissue mechanical responses in asthma pathophysiology has been recently recognized. Although nitric oxide (NO) is a mediator that controls smooth muscle tonus control in the airways, its effects on lung tissue responsiveness has not been previously investigated. We hypothesized that chronic nitric oxide synthase inhibition by L-NAME (false substrate for all nitric oxide synthases) treatment may modulate lung tissue mechanics, eosinophilic recruitment and extracellular matrix remodeling in a model of chronic pulmonary allergic inflammation. Guinea pigs were submitted to seven normal saline or ovalbumin exposures with increasing doses (1~5mg/mL-4weeks) and treated or not with L-NAME in drinking water. Seventy-two hours after the seventh inhalation the animals were anesthetized, exsanguinated, and oscillatory mechanics of lung tissue strips was performed in baseline condition and after ovalbumin challenge (0.1%). Using morphometry, we assessed the density of eosinophils, the number of iNOS and nNOS-positive cells, the density of actin, the collagen and elastic fibers content and the volume proportion of 8-iso-PGF2 in the alveolar septa. Ovalbumin-exposed animals presented an increase in baseline and maximal tissue resistance and elastance responses, eosinophil density, in the number of iNOS and nNOS positive cells, in the amount of collagen and elastic fibers and in the volume proportion of 8-iso-PGF2 in the alveolar septa compared to controls (p<0.05). L-NAME treatment in ovalbumin-exposed animals attenuated all lung tissue mechanical responses (p<0.01), reduced the number of iNOS and nNOS positive cells (p<0.01), elastic fiber content (p<0.001) and 8-isoPGF2 in the alveolar septa (p<0.001). However, this treatment did not affect the total number of eosinophils and collagen deposition. These data suggest that NO contributes to distal lung parenchyma constriction and to elastic fibers deposition in this model. These effects were associated to iNOS and nNOS activation in pulmonary parenchyma and with an increase in oxidative stress pathway activation

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-07-25T12:36:24Z No. of bitstreams: 1 alessasinsingerbrugiolo.pdf: 28268825 bytes, checksum: 19819230b54e983b1d5aa62f656ce02c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-09T13:50:57Z (GMT) No. of bitstreams: 1 alessasinsingerbrugiolo.pdf: 28268825 bytes, checksum: 19819230b54e983b1d5aa62f656ce02c (MD5) / Made available in DSpace on 2017-08-09T13:50:57Z (GMT). No. of bitstreams: 1 alessasinsingerbrugiolo.pdf: 28268825 bytes, checksum: 19819230b54e983b1d5aa62f656ce02c (MD5) Previous issue date: 2016-03-11 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / A asma é uma doença heterogênea, caracterizada por inflamação crônica das vias aéreas, definida pela história de sintomas respiratórios e associada a limitação variável do fluxo expiratório. Considerada um grave problema de saúde, estima-se que afete mais de 300 milhões de pessoas em todo o mundo. A resposta imunológica na asma envolve predominantemente linfócitos Th2, com elevados níveis de IgE total e alérgeno-específica e eosinofilia brônquica. O tratamento visa ao controle da doença e os medicamentos utilizados atualmente apresentam efeitos colaterais sistêmicos e, em geral, não são eficazes nos casos de asma de difícil controle, sendo crucial o desenvolvimento de novos tratamentos. Echinodorus grandiflorus é uma espécie vegetal conhecida como chapéu-de-couro muito utilizada por suas propriedades anti-inflamatórias. Em estudo anterior, o tratamento com o extrato aquoso dessa espécie reduziu a resposta imune patogênica Th2 no modelo de alergia pulmonar induzida por OVA. O ácido ferúlico é um ácido fenólico amplamente presente no reino vegetal e encontrado em E. grandiflorus que apresenta atividades antioxidante e anti-inflamatória. Neste trabalho, foram investigados os efeitos do extrato aquoso de E. grandiflorus, de suas frações metanólica e residual e do ácido ferúlico na modulação da resposta imune no modelo de alergia pulmonar. O extrato, as frações e o ácido ferúlico foram analisados por cromatografia líquida de alta eficiência. Para indução da alergia pulmonar camundongos fêmeas BALB/c foram sensibilizados intraperitonealmente com OVA e alumen nos dias 0 e 14. Nos dias 21, 23, 25, 27 e 29, os animais foram desafiados com OVA 1% por 20 minutos. Os tratamentos foram administrados por gavagem, entre os dias 21 e 29 do protocolo. Foram coletados soro, lavado broncoalveolar e pulmões. Inicialmente, a análise cromatográfica revelou dois ácidos fenólicos como componentes majoritários do extrato e das frações, possivelmente relacionados às suas atividades farmacológicas, entretanto, o ácido ferúlico não foi identificado no extrato e nas frações. Todos os tratamentos foram promissores na modulação da resposta patogênica Th2, com os melhores resultados obtidos com o extrato aquoso 25 mg/kg, fração metanólica 25 mg/kg, fração residual 100 mg/kg e ácido ferúlico 25 mg/kg. Foram observadas reduções do infiltrado inflamatório pulmonar, do número de células caliciformes produtoras de muco, do número total de células e de eosinófilos, linfócitos e neutrófilos no lavado bronco-alveolar, dos níveis de TSLP, IL-25, IL-33, IL-4, IL-5, IL-13, IFN-γ, CCL5, CCL11 e CCL20 no tecido pulmonar e níveis séricos de IgE e IgG1. Juntos, esses resultados indicam que o extrato aquoso de E. grandiflorus, suas frações metanólica e residual e o ácido ferúlico, reduzem a inflamação pulmonar alérgica, atuando principalmente na fase inicial da resposta imune, reduzindo a liberação de citocinas e quimiocinas pelas células epiteliais das vias aéreas. / Asthma is a heterogeneous disease characterized by chronic airway inflammation, defined by history of respiratory symptoms and associated with variable expiratory flow limitation. Regarded as a serious health problem affecting an estimated over 300 million people worldwide. The immune response in asthma is predominantly Th2 lymphocytes, with high levels of total and allergen-specific IgE and bronchial eosinophilia. Asthma treatment is aimed at controlling the disease and the drugs used currently have systemic side effects and generally are not effective in cases of asthma are difficult to control, and it is crucial the developing new treatments. Echinodorus grandiflorus is a plant species known as “chapéu-de-couro” widely used for their anti-inflammatory properties. In previous work, the treatment with the aqueous extract of this specie reduced the pathogenic Th2 response in the OVAinduced pulmonary allergy. The ferulic acid is a phenolic acid widely present in the plant kingdom and found in E. grandiflorus which has antioxidant and antiinflammatory activities. In this study, the effect of aqueous extract of E. grandiflorus, its methanol and residual fractions, and ferulic acid in modulating the immune response of pulmonary allergy model was investigated. The aqueous extract, fractions and ferulic acid were analyzed by high-performance liquid chromatography. For induction of pulmonary allergy female BALB/c mice were intraperitoneally sensitized with OVA and alum on days 0 and 14. On days 21, 23, 25, 27 and 29, animals were challenged with OVA 1% for 20 minutes. Treatments were administered by gavage, between days 21 and 29 of protocol. The serum, bronchoalveolar lavage fluid and lungs were collected. Chromatographic analysis revealed two phenolic acids as major components of extract and fractions that possibly are related to their pharmacological activities, however ferulic acid was not identified in the extract and fractions. The treatments were promising in the modulation of pathogenic Th2 response, with the best results obtained with the aqueous extract 25 mg/kg, methanolic fraction 25 mg/kg, residual fraction 100 mg/kg and ferulic acid 25 mg/kg. The treatments reduced the inflammatory infiltration in lung tissue, the number of goblet cells in lung tissue, the number of total cells, eosinophils, lymphocytes and neutrophils in bronchoalveolar lavage, the levels of TSLP, IL-25, IL33, IL-4, IL-5, IL-13, IFN-γ, CCL5, CCL11, and CCL20 in lung tissue, and the serum levels of IgE and IgG1. Taken together, these results indicate that the aqueous extract of E. grandiflorus, methanolic and residual fractions, and ferulic acid reduced the allergic pulmonary inflammation, act primarily in the early phase of the immune response, reducing the release of cytokines and chemokines by airways epithelial cells.