La matrice extracellulaire est composée d’environ 300 protéines et protéoglycanes qui constituent le matrisome et de 800 protéines associées (Naba et al., 2012a) et glycosaminoglycanes. C’est un protéome sous-exploré qui est modifié dans de nombreuses pathologies. Les fragments bioactifs issus de la matrice extracellulaire (matricryptines) sont capables de réguler des processus physiopathologiques et notamment l’angiogenèse et les pathologies cérébrales (Ricard-Blum and Salza, 2014). Environ 90 % des patients atteints de la maladie d’Alzheimer (MA) ont une angiopathie amyloïde cérébrale. L’angiogenèse contribue au déroulement de la MA. Nous nous sommes intéressés à l’endostatine (ES), une matricryptine du collagène XVIII qui possède des activités anti-angiogéniques, anti-tumorales et est également présente dans les plaques amyloïdes chez les patients atteints de la MA. Elle est libérée par les neurones et est capable de former des fibrilles amyloïdes in vitro (Kranenburg et al., 2003). Elle pourrait donc avoir une implication dans la MA. Nous avons montré que l'ES est présente dans le liquide céphalorachidien et que le rapport de sa concentration à celle des marqueurs classiques de la MA permet d’améliorer le diagnostic des patients atteint de démence fronto-temporale (DFT) et de discriminer les patients atteints de MA de ceux atteint de DFT et de pathologie nonMA/nonDFT. Nous avons établi les répertoires d’interactions extracellulaire du peptide -amyloïde (1-42) sous formes monomérique, oligomérique, fibrillaire ou agrégée et montré que l’oligomérisation et la fibrillogenèse augmentent la capacité d’interaction du peptide -amyloïde. Nous avons établi le réseau d’interaction global de l’endostatine par résonance plasmonique de surface en mode imagerie et identifiés 21 nouveaux partenaires de cette matricryptine. Nous avons plus particulièrement caractérisé son interaction avec la Procollagen C-Proteinase Enhancer-1, une protéine dont nous avons montré qu’elle donne naissance à une matricryptine anti-angiogénique. Nous avons enfin construit les réseaux d’interactions extracellulaires spécifiques de l’angiogenèse et de la maladie d’Alzheimer et des processus amyloïdes pour identifier les protéines connectant ces deux processus qui sont des cibles thérapeutiques potentielles. Ces réseaux d’interactions ont été créés à l’aide de 239 interactions que nous avons identifiées expérimentalement et des interactions décrites dans la littérature. Ces données seront à terme disponibles dans la base de données spécifique des interactions extracellulaires créée au laboratoire, MatrixDB, dans la nouvelle version à laquelle nous avons contribué. / The extracellular matrix include approximately 300 proteins and proteoglycans which constitute the matrisome and 800 associated proteins (Naba et al., 2012a) and glycosaminoglycans. It is an under-explored proteome which is modified in many diseases. Extracellular matrix bioactives fragments (matricryptins) are able to regulate physiopathological process like angiogenesis and cerebral disorders (Ricard-Blum and Salza, 2014). About 90 % of patients with Alzheimer's disease (AD) have cerebral amyloid angiopathy. Angiogenesis contributes to the development of AD. We are studying endostatin (ES), a matricryptin of collagen XVIII which has anti-angiogenic and anti-tumoral activities and is also present in amyloid plaques in AD patients. ES is released by neurons and is able to form amyloid fibrils in vitro (Kranenburg et al., 2003). This anti-angiogenic matricryptin could therefore be involved in AD. We have shown that ES is present in the cerebrospinal fluid of AD patients and the ratio of its concentrations to conventional markers of AD improves the diagnosis of patients with frontotemporal dementia (FTD) and discriminate AD patients from those suffering from FTD and pathology noAD/noDFT. We have established the extracellular interactions repertoires of the -amyloid peptide (1-42) in monomeric, oligomeric, fibrillar or aggregated forms and showed that the oligomerization and fibrillogenesis increase the interaction capacity of the -amyloid peptide. We have established the global interaction network of endostatin by surface plasmon resonance imaging and identified 21 new partners of this matricryptin. Specifically, we characterized its interaction with the Procollagen C-Proteinase Enhancer-1, a protein which gives rise to an anti-angiogenic matricryptin. We finally built networks of specific extracellular interactions of angiogenesis and of Alzheimer's disease and amyloid process to identify proteins connecting these two processes that are potential therapeutic targets. These interaction networks have been built using 239 interactions including those we have identified experimentally and those described in the literature. This data will be available in the database specific of extracellular interactions created in the laboratory, MatrixDB, in the new version of which we contributed.

Diabetic foot disease (DFD) is a serious complication of diabetes and, along with critical limb ischemia, significantly exacerbates the prognosis of patients. Peripheral arterial disease in patients with diabetes has an atypical clinical course, its diagnosis is challenging and is one of the most common causes of morbidity and mortality of patients with DFD. The aim of this dissertation focused on the diagnosis and treatment of DFD was to identify a suitable method for evaluating the effect of autologous cell therapy (ACT), to assess options for early diagnosis of Charcot osteoarthropathy (COA) and, possibly, to establish the association between the incidence of cardiovascular disease and DFD. In our studies concerning therapeutic vasculogenesis, we observed a significant increase in the antiangiogenic factor endostatin after ACT in contrast to its unchanged levels after standard percutaneous transluminal angioplasty; the transient increase in endostatin seems to be a marker of therapeutic vasculogenesis after ACT. A benefit of using calf muscle perfusion scintigraphy in the assessment of microcirculation and ACT effect was not clearly demonstrated. By contrast, a promising method for the evaluation of microcirculation and the effect of revascularization after ACT was MR spectroscopy of calf...

Diversas doenças estão associadas com a formação de novos vasos a parti vasos pré-existentes, ou angiogênese. Dentre elas está a aterosclerose (Griffioen & Molema, 2000). Pesquisas recentes demonstram que a hipercolesterolemia, que têm um papel importante na fisiologia da aterosclerose, também pode prejudicar a ação de fatores angiogênicos (Jang et.al., 2000). A hipercolesterolemia que é decorrente de aumento de LDL no plasma ocasiona um aumento no tempo de permanência desta partícula na circulação (Yasunobu, 2001). Contudo, a LDL pode sofrer modificação na circulação, dando origem a uma subfração mais eletronegativa da LDL, a LDL (-). A LDL (-) pode prejudicar cada etapa da angiogênese, desregulando a função endotelial (Tai et. al., 2006). Em nosso estudo, vimos que apesar da LDL (-) ter estimulado a miga celular, esta partícula inibiu a formação de túbulos in vitro. A LDL (-) não foi capa afetar a angiogênese in vivo. / A large number of diseases is associated with formation of new blood vessels out of pre-existing capillaries, or angiogenesis. These diseases include the atherosclerosis (Griffioen & Molema, 2000). Resents researches demonstrate that the hypercholesterolemia, that have a important role in the physiology of the atherosclerosis, can impaired the angiogenesis (Jang et. al., 2000) . The hypercholesterolemia that is decurrente of high levels of LDL in the plasma causes an increase in the time of permanence this particle in the circulation (Yasunobu, 2001). However, the LDL can to suffer modification in the circulation, giving rise to a subfration more eletronegative from LDL, the LDL (-). The LDL (-) could impair each one of the steps of the angiogenesis, thereby dysregulating endothelial function (Tai et. al., 2006). In our study, see that despite the LDL (-) have stimulated the cell migration, this particle inhibited the Tube formation in vitro. The LDL (-) didn\'t affect the angiogenesis in vivo.

Diversas doenças estão associadas com a formação de novos vasos a parti vasos pré-existentes, ou angiogênese. Dentre elas está a aterosclerose (Griffioen & Molema, 2000). Pesquisas recentes demonstram que a hipercolesterolemia, que têm um papel importante na fisiologia da aterosclerose, também pode prejudicar a ação de fatores angiogênicos (Jang et.al., 2000). A hipercolesterolemia que é decorrente de aumento de LDL no plasma ocasiona um aumento no tempo de permanência desta partícula na circulação (Yasunobu, 2001). Contudo, a LDL pode sofrer modificação na circulação, dando origem a uma subfração mais eletronegativa da LDL, a LDL (-). A LDL (-) pode prejudicar cada etapa da angiogênese, desregulando a função endotelial (Tai et. al., 2006). Em nosso estudo, vimos que apesar da LDL (-) ter estimulado a miga celular, esta partícula inibiu a formação de túbulos in vitro. A LDL (-) não foi capa afetar a angiogênese in vivo. / A large number of diseases is associated with formation of new blood vessels out of pre-existing capillaries, or angiogenesis. These diseases include the atherosclerosis (Griffioen & Molema, 2000). Resents researches demonstrate that the hypercholesterolemia, that have a important role in the physiology of the atherosclerosis, can impaired the angiogenesis (Jang et. al., 2000) . The hypercholesterolemia that is decurrente of high levels of LDL in the plasma causes an increase in the time of permanence this particle in the circulation (Yasunobu, 2001). However, the LDL can to suffer modification in the circulation, giving rise to a subfration more eletronegative from LDL, the LDL (-). The LDL (-) could impair each one of the steps of the angiogenesis, thereby dysregulating endothelial function (Tai et. al., 2006). In our study, see that despite the LDL (-) have stimulated the cell migration, this particle inhibited the Tube formation in vitro. The LDL (-) didn\'t affect the angiogenesis in vivo.