Haemophilus parasuis est un pathogène porcin causant la maladie de Glässer caractérisée par de la polysérosite fibrineuse, polyarthrite, méningite et septicémie. La pathogenèse de l’infection et les facteurs de virulence sont encore mal connus. Le site de colonisation de Haemophilus parasuis dans le tractus respiratoire supérieur est controversé. Pour accéder à la circulation sanguine, H. parasuis doit envahir la muqueuse. H. parasuis adhère à des cellules épithéliales porcines de trachée (NPTr). Pour accéder au système nerveux central et causer la méningite, H. parasuis doit traverser la barrière hémato-méningée. H. parasuis adhère à et envahit des cellules endothéliales porcines de microvaisseaux cérébraux (PBMEC) provenant de la BBB. Le but de cette étude était d’étudier certaines interactions entre H. parasuis et son lipooligosccharide (LOS), et des cellules endothéliales et épithéliales porcines. Les résultats démontrent que l’adhésion de H. parasuis Nagasaki aux NPTr et aux PBMEC est en partie médiée par son LOS. H. parasuis induit l’apoptose des NPTr et des PBMEC, mais le LOS ne semble pas impliqué. H. parasuis, et à un niveau moindre son LOS, stimulent la sécrétion d’interleukine- (IL) 6 et d’IL-8. Différentes souches de H. parasuis sérotypes 4 et 5 (sérotypes les plus prévalents en Amérique du Nord) stimulent également les NPTr et PBMEC à produire IL-6 et IL-8. Les résultats suggèrent que le LOS de H. parasuis joue un certain rôle dans la pathogenèse de l’infection, mais d’autres composantes bactériennes sont également impliquées. / Haemophilus parasuis is a swine pathogen that causes Glässer’s disease characterized by fibrinous polyserositis, polyarthritis, meningitis and septicemia. The pathogenesis of the infection and virulence factors are not well known. Whether the upper respiratory tract is the site of colonization of H. parasuis is still a controversial issue. H. parasuis must invade the mucosa to gain access to the bloodstream. H. parasuis is able to adhere to newborn pig trachea cells (NPTr). H. parasuis must then cross the blood-brain barrier to gain access to the central nervous system in cases of meningitis. H. parasuis is able to adhere to and invade porcine brain microvascular endothelial cells (PBMEC). The aim of this work was to study the interactions between H. parasuis, its lipooligosccharide (LOS), and porcine endothelial and epithelial cells. Results showed that adhesion of H. parasuis Nagasaki to NPTr and PBMEC was partially mediated by its LOS. H. parasuis induced NPTr and PBMEC apoptosis, although purified LOS does not seem to be involved. H. parasuis, and to a lesser extent its LOS, stimulated the release of interleukin- (IL) 6 and IL-8. Field strains of H. parasuis serotypes 4 and 5 (the most prevalent serotypes in North America) also induced the production of IL-6 and IL-8. Results suggest that H. parasuis LOS plays a role in the pathogenesis of the infection, but other bacterial components are also involved.

Submitted by Natalie Mendes (nataliermendes@gmail.com) on 2015-07-28T23:01:37Z No. of bitstreams: 1 COMPOSI??O QU?MICA DO ?LEO ESSENCIAL DE Lippia origanoides Kunth E ATIVIDADE ANTIMICROBIANA FRENTE A DIFERENTES SOROTIPOS~1.pdf: 1434340 bytes, checksum: 8072381e4bdaa1aac1583317e834ac0d (MD5) / Made available in DSpace on 2015-07-28T23:01:37Z (GMT). No. of bitstreams: 1 COMPOSI??O QU?MICA DO ?LEO ESSENCIAL DE Lippia origanoides Kunth E ATIVIDADE ANTIMICROBIANA FRENTE A DIFERENTES SOROTIPOS~1.pdf: 1434340 bytes, checksum: 8072381e4bdaa1aac1583317e834ac0d (MD5) Previous issue date: 2014-03-28 / Pig farming has become increasingly important in recent years in Brazil, because of this, studies for the treatment of diseases that cause the loss of mass of meat animals has increased significantly, such as the Glasser's disease caused by Haemophilus parasuis. Some initial studies have shown human resistance to antibiotics due to the consumption of meat produced with high levels of these substances, and alternatively treatments have been developed from natural products. Lippia origanoides Kunth is presented as a natural source of antimicrobial substances due to the composition of the essential oil obtained, mainly, from the leaves of this plant. In this study the antimicrobial activity of the essential oil from Lippia origanoides Kunth, by determining the minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) against Haemophilus parasuis serotypes 1,2,4,5,9,10,12,13,14 and one untypable was studied. Essential oils were obtained by hydrodistillation of the dried leaves and the chemical composition analysis revealed the presence of carvacrol as the predominant component, which characterizes the chemotype B. The results of the antimicrobial activity demonstrated the inhibitory effect of essential oil samples for all tested bacteria. The best result was 0.005% against the sample MV12315 (serotype 10) while the least satisfactory was 0.078% against the sample MV12196 (serotype 12). Results demonstrate the bactericidal action of the oil against the different serotypes of Haemophilus parasuis. / A suinocultura vem se sobressaindo nos ?ltimos anos no Brasil, por isso aumentam os estudos para tratamento das doen?as que causam perdas de carca?a dos animais, como a doen?a de Gl?sser, provocada pelo Haemophilus parasuis. Alguns trabalhos incipientes demonstram a resist?ncia humana a antibi?ticos devido ao consumo de carnes produzidas com altos ?ndices destas subst?ncias, e tratamento alternativos com produtos naturais vem sendo desenvolvidos. Lippia origanoides Kunth se apresenta como uma fonte natural de subst?ncias antimicrobianas devido ? composi??o do seu ?leo essencial obtido principalmente das folhas desta planta. Este trabalho avaliou a atividade antimicrobiana do ?leo essencial de Lippia origanoides atrav?s da determina??o da Concentra??o Inibit?ria M?nima (CIM) e Concentra??o Bactericida M?nima (CBM) frente a amostras de campo do Haemophilus parasuis com sorotipos 1,2,4,5,9,10,12,13,14 e um n?o sorotip?vel. Os ?leos essenciais foram obtidos por hidrodestila??o das folhas secas ap?s tr?s horas, e na an?lise da composi??o qu?mica, o carvacrol foi identificado como componente predominante, caracterizando-o como quimiotipo B. Os resultados de atividade antimicrobiana demonstram o efeito inibit?rio do ?leo essencial para todas as amostras de bact?rias testadas. O melhor resultado encontrado foi de 0,005% frente a amostra MV12315 (sorotipo 10) enquanto o menos satisfat?rio foi de 0,078% contra a amostra MV12196 (sorotipo 12). Os resultados obtidos demonstram a a??o bactericida do ?leo para os diferentes sorotipos do Haemophilus parasuis.

Haemophilus parasuis est un pathogène porcin causant la maladie de Glässer caractérisée par de la polysérosite fibrineuse, polyarthrite, méningite et septicémie. La pathogenèse de l’infection et les facteurs de virulence sont encore mal connus. Le site de colonisation de Haemophilus parasuis dans le tractus respiratoire supérieur est controversé. Pour accéder à la circulation sanguine, H. parasuis doit envahir la muqueuse. H. parasuis adhère à des cellules épithéliales porcines de trachée (NPTr). Pour accéder au système nerveux central et causer la méningite, H. parasuis doit traverser la barrière hémato-méningée. H. parasuis adhère à et envahit des cellules endothéliales porcines de microvaisseaux cérébraux (PBMEC) provenant de la BBB. Le but de cette étude était d’étudier certaines interactions entre H. parasuis et son lipooligosccharide (LOS), et des cellules endothéliales et épithéliales porcines. Les résultats démontrent que l’adhésion de H. parasuis Nagasaki aux NPTr et aux PBMEC est en partie médiée par son LOS. H. parasuis induit l’apoptose des NPTr et des PBMEC, mais le LOS ne semble pas impliqué. H. parasuis, et à un niveau moindre son LOS, stimulent la sécrétion d’interleukine- (IL) 6 et d’IL-8. Différentes souches de H. parasuis sérotypes 4 et 5 (sérotypes les plus prévalents en Amérique du Nord) stimulent également les NPTr et PBMEC à produire IL-6 et IL-8. Les résultats suggèrent que le LOS de H. parasuis joue un certain rôle dans la pathogenèse de l’infection, mais d’autres composantes bactériennes sont également impliquées. / Haemophilus parasuis is a swine pathogen that causes Glässer’s disease characterized by fibrinous polyserositis, polyarthritis, meningitis and septicemia. The pathogenesis of the infection and virulence factors are not well known. Whether the upper respiratory tract is the site of colonization of H. parasuis is still a controversial issue. H. parasuis must invade the mucosa to gain access to the bloodstream. H. parasuis is able to adhere to newborn pig trachea cells (NPTr). H. parasuis must then cross the blood-brain barrier to gain access to the central nervous system in cases of meningitis. H. parasuis is able to adhere to and invade porcine brain microvascular endothelial cells (PBMEC). The aim of this work was to study the interactions between H. parasuis, its lipooligosccharide (LOS), and porcine endothelial and epithelial cells. Results showed that adhesion of H. parasuis Nagasaki to NPTr and PBMEC was partially mediated by its LOS. H. parasuis induced NPTr and PBMEC apoptosis, although purified LOS does not seem to be involved. H. parasuis, and to a lesser extent its LOS, stimulated the release of interleukin- (IL) 6 and IL-8. Field strains of H. parasuis serotypes 4 and 5 (the most prevalent serotypes in North America) also induced the production of IL-6 and IL-8. Results suggest that H. parasuis LOS plays a role in the pathogenesis of the infection, but other bacterial components are also involved.

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