Cardiovascular diseases are considered the first cause of death in westernized societies. They are directly linked to atherosclerosis, a clinical condition characterized by a thickening of the arterial wall. Atherosclerosis is in his turn linked to various genetic and environmental factors; among those factors are high oxidized LDL levels and endothelial dysfunction. In the present study, we have analyzed in vitro the effect of myeloperoxidase oxidized LDL on endothelial cells at the level of fibrinolysis and cell motility.<p>In the first part of the work, we measured fibrinolysis in real time at the surface of endothelial cells. Our results suggest that myeloperoxidase oxidized LDL interferes with the regulation of fibrinolysis by endothelial cells by decreasing their pro-fibrinolytic activity. This effect was not related to a modification in expression of major regulators of fibrinolysis such as PAI-1 and t-PA. Our data link the current favorite hypothesis that oxidized LDL has a causal role in atheroma plaque formation with an old suggestion that fibrin may also play a causal role. A model that best explains our results would be as follows: oxidized LDL increases fibrin deposition on endothelial cells which will increase their permeability resulting in more oxidized LDL infiltration into the subendothelial space of the arterial wall initiating atherogenesis. <p>In the second part of the work, we investigated the effect of myeloperoxidase oxidized LDL at the level of endothelial cell motility. We have shown that oxidized LDL is able to decrease cell migration, wound healing and tubulogenesis in endothelial cells. Those effects were not associated with any alteration at the level of neither cell viability nor proliferation. Subsequent gene expression analyses enabled us to link the oxidized LDL induced phenotypical changes in the cells to a change in expression of both microRNA-22 and Heme Oxygenase 1 genes. Our observations suggest a novel role of oxidized LDL not only as an important factor in the initiation of atheromatous lesions, but also as a potential player in the progression of the atherosclerosis disease by impeding blood vessel repair and wound healing at the sites of lesions.<p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Abstract Matrix metalloproteinases (MMPs) are the zinc-dependent endopeptidases which belong to a large family of proteases. MMPs are responsible for degradation and remodeling of extracellular matrix proteins during growth, organogenesis and tissue turnover. Besides their role in physiological processes, MMPs also influence various pathological processes, i.e., inflammatory diseases and cancers, in which MMPs may ultimately lead to unwanted tissue destruction. One of the most widely studied MMPs is MMP-8. MMP-8 was previously thought to be expressed only by neutrophils. Presently, it is evident that MMP-8 can be expressed in a wide range of cells such as macrophages, plasma cells, T-cells, endothelial cells, smooth muscle cells, oral epithelial cells, fibroblasts etc. MMP-8 has been previously studied in inflammation and malignancies. High serum MMP-8 concentration is associated with the presence of atherosclerosis and poor cardiovascular disease prognosis, while higher plasma MMP-8 levels protect against lymph node metastasis. Certain MMP-8 gene variations can alter promoter activity and subsequent gene expression. MMP-8 gene variation influences obstetrical outcomes, and lung and breast cancer prognosis. For our study, we hypothesized that systemic levels of MMP-8 correlate with its genetic variations and appear as novel risk markers for disease. We aimed to address the potential role of MMPs and their regulators with a special focus on MMP-8 in distinct sets of inflammatory and malignant diseases, i.e. arterial diseases, and head and neck squamous cell cancer (HNSCC). We demonstrated that the combination of high serum MMP-8 and low myeloperoxidase (MPO) levels is an important risk marker for arterial disease. Further, we demonstrated that MMP-8 gene variation is protective against arterial diseases. Interestingly, we were able to demonstrate an association between MMP-8 gene variation and serum MMP-8 concentration in a healthy population. On the other hand, we showed that plasma tissue inhibitor of matrix metalloproteinases (TIMP-1) concentration is associated with survival in HNSCC patients and TIMP-1 genotype is associated with plasma TIMP-1 levels in women only. Collectively, our study showed that serum MMP-8 levels can be used as an important risk marker in arterial disease and TIMP-1 levels in HNSCC patients. Based on our results, the hypothesis raised has been widely confirmed. Additionally, our study has warranted the need for further investigation involving a larger number of patients. If our results are replicable, serum MMP-8 and plasma TIMP-1 could be used to develop diagnostic tools as well as treatment regimes in clinics. / Tiivistelmä Matriksin metalloproteinaasit (MMP:t) ovat sinkkiriippuvaisia endopeptidaaseja, jotka kuuluvat laajaan proteiineja pilkkovaan proteolyyttiseen entsyymi perheeseen. MMP:ien tehtävä on pilkkoa ja uudelleen muokata soluväliaineen proteiineja kasvun, elinten kehityksen ja kudosten uusiutumisen aikana, mutta MMP:t toimivat aktiivisesti myös patologisissa prosesseissa, kuten tulehdustiloissa ja syövissä. Syövissä MMP:en vaikutus voi johtaa ei-toivottuun kudostuhoon. Yksi laajimmin tutkituista MMP-ryhmän entsyymeistä on MMP-8, jonka alunpitäen ajateltiin ilmenevän vain neutrofiileissä. Nykytietämyksen mukaan MMP-8:aa ilmentyy myös mm. makrofaageissa, plasmasoluissa, T-soluissa, endoteelisoluissa, sileälihassoluissa, suun limakalvon epiteelisoluissa ja fibroplasteissa. MMP-8:aa on aikaisemmin tutkittu erityisesti tulehdustiloissa ja pahanlaatuisissa kasvaimissa. Korkean MMP-8 seerumipitoisuuden on havaittu liittyvän valtimokovettumatautiin ja huonoon ennusteeseen sydän- ja verisuonisairauksissa, kun taas kohonnut MMP-8:n pitoisuus plasmassa suojaa imusolmuke-etäpesäkkeiltä. Tiedetään, että tietyt muutokset MMP-8:n geenissä voivat muuttaa sen promoottoriaktiviteettia ja täten säädellä geenin ilmentymistä. MMP-8:n geenimuutokset vaikuttanevat raskaudenkulkuun sekä keuhko- ja rintasyövän ennusteeseen. Tutkimushypoteesimme mukaan MMP-8:n seerumipitoisuudet riippuvat vaihtelusta MMP-8:aa koodaavassa geenissä ja niitä voidaan pitää uusina riskinarvioinnin merkkiaineina tautitiloissa. Tavoitteenamme oli osoittaa yleisesti MMP:ien ja erityisesti MMP-8:n sekä näiden proteinaasien säätelytekijöiden merkitys tietyissä tulehdustiloissa ja maligniteeteissa, kuten sepelvaltimotaudissa ja pään ja kaulan alueen syövissä. Havaitsimme, että korkea MMP-8 seerumipitoisuus ja alhainen myeloperoksidaasitaso yhdistyvät vahvasti valtimotautiriskiin. Lisäksi osoitimme, että tietty MMP-8:n geenimuunnos on suojaava tekijä valtimotaudille ja että MMP-8:n seerumikonsentraatio on siitä riippuvainen terveillä tutkituilla. Tämän lisäksi todensimme, että MMP:n kudosestäjän (tissue inhibitor of matrix metalloproteinases, TIMP-1) plasmapitoisuus liittyy pään ja kaulan alueen levyepiteelisyöpää sairastavien potilaiden eloonjääntiin ja että TIMP-1:n genotyyppi liittyy sen plasmapitoisuuteen ainoastaan naisilla. Tulostemme mukaan seerumin MMP-8-pitoisuutta voidaan pitää hyvänä riskinarviointivälineenä verisuonitaudeissa sekä TIMP-1-pitoisuutta vastaavasti pään ja kaulan alueen levyepiteelisyövissä. Saadut tulokset tukevat olettamustamme, jonka mukaan MMP-8 on tärkeä tautimarkkeri. Tämä on lisännyt kiinnostusta selvittää MMP:ien merkitystä laajemmin muissa tulehdustiloissa ja syövissä. Jos tulokset saadaan toistetuksi laajemmassa tutkimusaineistossa, seerumin MMP-8:sta voidaan kehittää kliinisten ja analyyttisten laboratorioiden käyttöön sopiva diagnostinen menetelmä.

The deleterious effects of MPO make it a new target for medicinal research. The aim of our study is to find promising inhibitors of MPO for using them as starting point of new anti-inflammatory drugs. Depending on previous researches on MPO inhibitors, we selected 5-fluorotryptamine as starting compounds. Using docking experiments, we designed a series of compounds derived from 5-fluorotryptamine. Two modifications were proposed: <p>& / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

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Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-08-29T21:11:40Z No. of bitstreams: 1 Silvana Sousa Paz Avaliação de marcadores....pdf: 756990 bytes, checksum: 5aac886be232eac44d86b25a30837ac4 (MD5) / Made available in DSpace on 2012-08-29T21:11:40Z (GMT). No. of bitstreams: 1 Silvana Sousa Paz Avaliação de marcadores....pdf: 756990 bytes, checksum: 5aac886be232eac44d86b25a30837ac4 (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / As leucemias são malignidades hematopoiéticas, caracterizadas por subgrupos biologicamente distintos, sendo os tipos mais frequentes de cânceres em crianças e adolescentes. Polimorfismos em genes de enzimas que metabolizam xenobióticos podem estar relacionados com a inserções/deleções, polimorfismos de nucleotídeo simples (SNP’s) e variações no número de cópias e têm sido relacionados com a patogênese de algumas neoplasias hematológicas, como a leucemia linfóide aguda (LLA). O objetivo deste estudo foi o de determinar as frequências de polimorfismos em genes associados ao estresse oxidativo e metabolismo de xenobióticos (GSTT1, GSTM1, CYP2E1, NQO1 e MPO), em pacientes pediátricos com LLA, associando-as a aspectos clínicos e marcadores de evolução da doença. A casuística foi composta por 37 pacientes pediátricos seguidos na clínica ONCO e tratados pelo protocolo GBTLI-LLA 93. O perfil hematológico dos pacientes foi realizado ao diagnóstico e durante o tratamento e os polimorfismos gênicos foram investigados por reação da polimerase em cadeia - polimorfismo de tamanho de fragmento de restrição (PCR-RFLP) e por reação da polimerase em cadeia multiplex (PCR Multiplex). As análises estatísticas apresentaram significância para os valores de leucócitos totais nos D1 e D7 (p= 0,0016) e nos D1 e D14 (p= 0,0059); linfócitos nos D1 e D7 (p= 0,0088) e D1 e D14 (p= 0,0101); segmentados neutrófilos nos D1 e D7 (p= 0,0033) e D1 e D14 (p= 0,0252); blastos periféricos D1 e D7 (p< 0,0001) e D1 e D14 (p< 0,0001) e; para a contagem de blastos na medula óssea (MO) nos D1 e D15 (p<0,0001), D1 e D28 (p< 0,0001) e D15 e D28 (p= 0,0005). As frequências alélicas e genotípicas para os genes estudados estavam em equilíbrio de Hardy-Weinberg. A mutação do gene MPO foi associada a infiltração da MO (p= 0,0473) e presença de blastos no líquor (p= 0,0473). O polimorfismo do gene GSTT1 foi associado à contagem de leucócitos (p= 0,014) e plaquetas (p= 0,0034) no D1 e a contagem de leucócitos (p=0,037) e segmentados neutrófilos (p= 0,0008) no D7. A presença do polimorfismo no gene NQO1 foi associado à infiltração da MO (p= 0,0410) e a presença de blastos no líquor (p= 0,0410). Entretanto, o polimorfismo NQO1 apresentou associação com a presença de palidez (p=0,0096). Os dados encontrados corroboram em parte com dados encontrados na literatura, sendo necessária a realização de um estudo com numero maior de pacientes para confirmação dos achados relacionados aos genes investigados e a LLA. / Leukemia is characterized by biologically distinct subgroups and is the most frequent hematological malignity in childhood. Polymorphisms in genes of enzymes that metabolize xenobiotics may be related to insertions/ deletions, single nucleotide polymorphisms (SNP's) and gene copies variation and have been related to the pathogenesis of some hematologic malignancies, including acute lymphoblastic leukemia (ALL). The aim of this study was to investigate genes polymorphisms associated with the oxidative stress and xenobiotic metabolism (GSTT1, GSTM1, CYP2E1, NQO1 and MPO) in a group of childhood ALL patients, associating them with clinical evolution and prognostic markers. The casuistic was compound by 37 pediatric patients followed and treated at the clinic ONCO with the protocol GBTLI-LLA 93. The hematological profile of patients was performed at diagnosis and during treatment and gene polymorphisms were investigated by Polimerase Chain Reaction - Restriction Fragment Length Polymorfism (PCR-RFLP) and Polimerase Chain Reaction Multiplex (Multiplex PCR). Statistical analyses were significant for values of total leukocytes in D1 and D7 (p= 0.0016) and in D1 e D14 (p= 0.0059); lymphocytes in D1 and D7 (p= 0.0088), D1 and D14 (p= 0.0101); neutrophils in D1 and D7 (p= 0.0033), D1 and D14 (p= 0.0252). It was also find statistical significance at the number of peripheral blasts in D1 and D7 (p< 0.0001), D1 and D14 (p< 0.0001); the blast count in bone marrow (BM) in D1 and D15 (p<0.0001), D1 and D28 (p< 0.0001) and D15 and D28 (p= 0.0005). The allelic and genotypic frequencies of all gene polymorphism investigated were in Hardy-Weinberg equilibrium. The MPO gene mutation was associated with infiltration of the BM in D28 (p= 0.0473) and the presence of blasts in the CSF (p= 0.0473). The GSTT1 gene polymorphism was associated with leukocyte (p= 0.014) and platelet counts (p= 0.0034) in D1 and with leukocytes (p=0,037) and neutrophils counts (p= 0.0008) in D7. The NQO1 gene polymorphism presence was associated with BM infiltration at D28 (p= 0.0410) and the presence of blasts in the CSF (p= 0.0410). However, the NQO1 polymorphism was associated with the presence of pallor (p=0.0096). Result described here corroborated in part with previous described data, being necessary to carry out additional study with a larger number of patients to confirm the finding related to genes polymorphism investigated and the clinical evolution of ALL patients.

Le syndrome de l’intestin irritable (SII) et le syndrome de la vessiedouloureuse (SVD) sont tous deux caractérisés par une hypersensibilité viscérale àla distension. Sur le plan épidémiologique, ces deux syndromes sont étroitementassociés puisque les patients SII ont une prévalence du syndrome de la vessiedouloureuse 7 fois plus élevée que la population générale. Cependant, le mécanismeresponsable de la sensibilisation du tube digestif et de l’appareil urinaire n’a jamaisété étudié. Compte tenu de l’innervation commune de ces deux organes, il estprobable que ce mécanisme mette en jeu sur le long terme des phénomènes de laplasticité neuro-gliale aux niveaux communs d’intégration de la sensibilité pelvienne.L’objectif général de ce travail était d’établir et de caractériser un modèleanimal de sensibilisation croisée vessie/colon, aigu et chronique, afin de mieuxcomprendre les mécanismes impliqués dans l’hypersensibilité viscérale croisée. / Irritable bowel syndrome (IBS) and Bladder pain syndrome (BPS) are bothcharacterized by visceral hypersensitivity to distension. Epidemiology showed thatthese two syndromes are closely associated since IBS patients have a prevalence ofbladder pain syndrome that is 7 times higher than the general population. However,the mechanism responsible for sensitization of the gastrointestinal tract and theurinary tract has never been studied. Given the common innervation of these twoorgans, it is likely that this mechanism involves long-term phenomena of neuro-glialplasticity at the common levels of integration of pelvic sensitivity.The overall objective of this work was to establish and characterize an animalmodel of bladder / colon cross-sensitization, acute and chronic, to better understandthe mechanisms involved in cross-visceral hypersensitivity.