Indiana University-Purdue University Indianapolis (IUPUI) / The degradation of the resin-dentin interface after restoration placement is multifactorial and can be attributed in part to matrix metalloproteinases (MMPs) enzymes associated with recurrent and secondary caries progression. This dissertation aimed to synthesize and characterize the effects of Epigallocatechin-3-gallate (EGCG) from green tea extract as an MMP-inhibitor loaded into a dental adhesive using slow therapeutic compound release nanotubes as a reservoir to allow sustained and slow release. Loading efficiency and drug release were evaluated using a UV-vis spectrometer. The effects on the degree of conversion (DC), polymerization conversion (PC), and Vickers Micro-Hardness (VHN) tests were performed. MMP mediated β-casein (bCN) cleavage rate was used to determine the potency of the eluates contained EGCG to inhibit MMP-9 activity. The results indicated that HNTs could hold about 21.35% (±4.2%) of the EGCG used in the encapsulation process. The addition of 7.5% HNT or 7.5% EGCG-encapsulated HNT adhesive groups did not alter the curing efficiency indicated by the degree of conversion, polymerization conversion, and surface hardness results compared to the control group (p> 0.05). A statistically significant influence of adding HNTs was found to slow down the EGCG release measured up to 8 weeks (p< 0.05). There was a significant decrease in the degradation of β-casein mediated by pre-activated MMP-9 exposed to eluates from EGCG adhesives compared to non-EGCG adhesive groups (p< 0.05). The results suggested that using HNTs for EGCG encapsulating can remedy the negative impact of EGCG on the adhesive’s polymerization and still have the MMP-inhibitory effect and longer release period. Dentin adhesive containing EGCG-encapsulated HNT may contribute to the long-term preservation of restorations through slow and controlled release to maintain the dentin-resin interface's integrity by inhibiting MMP activity.

The Drosophila heart is a tubular vessel surrounded by a dynamic scaffold of extracellular matrix (ECM) proteins. Heart development and function rely upon protease-mediated remodelling and turnover of the ECM, and changes in ECM composition correlate with age and cardiac disease. Previous research has shown that a family of proteases called matrix metalloproteinases (MMPs), and their inhibitors (TIMPs), are necessary for normal cardiac cell migration and lumenogenesis. The Drosophila heart expands considerably throughout growth, but the role of MMP activity has not been elucidated at this time. I examine the role of the two Drosophila MMPs, MMP1 and MMP2, as well as TIMP, in defining larval heart structure and ECM protein distribution. I observe heart phenotypes via immunofluorescence labelling and confocal microscopy using loss-of-function mutants, gene over-expression, and gene knock-down techniques. Reduced MMP1 function during embryogenesis correlates with myofibrillar disorganisation, whereas reduced MMP2 function or TIMP over-expression both result in cardia bifida as well as increased density and ectopic localisation of Collagen-IV and Pericardin. Post-embryonic MMP reduction compromises cardiac structural integrity but does not affect Pericardin localisation. Live imaging of the larval heart with optical coherence tomography (OCT) and light microscopy reveals that reduced MMP2 function correlates with decreased heart rate but not impaired dilation or contraction. These data suggest that MMP2 activity during embryogenesis is critical for larval heart development. In contrast, post-embryonic protease function appears to have a less pronounced effect on ECM protein distribution throughout larval development. / Thesis / Master of Science (MS) / The fruit fly (Drosophila) heart undergoes significant changes in organisation and size throughout development and growth. The heart is surrounded and supported by a network of extracellular matrix (ECM) proteins, which is regulated by proteases, including matrix metalloproteinases (MMPs). Previous research has shown that MMPs are required for normal heart formation. I demonstrate that a reduction in MMP activity during embryonic development results in larval heart defects and an increase in the disorganisation of ECM proteins around the heart, whereas reduction during larval development results in less pronounced protein mislocalisation. These findings are corroborated via over-expression of an MMP inhibitor.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

A radioterapia é um dos principais tratamentos para pacientes com câncer de cabeça e pescoço e a cárie relacionada à radioterapia é um de seus efeitos colaterais, apresentando-se com alta taxa de ocorrência. Além disso, falhas precoces em restaurações realizadas em dentes de pacientes irradiados em cabeça e pescoço também são observadas. Como a degradação enzimática do colágeno ocorre principalmente através da atividade das metaloproteinases de matriz e das cisteínacatepsinas, o objetivo deste estudo foi avaliar a atividade enzimática da dentina hígida e restaurada de dentes submetidos à radioterapia in vivo e in vitro. Os dentes irradiados in vivo foram extraídos de pacientes submetidos à radioterapia com uma dose cumulativa que variou de 40 a 70 Gy. As extrações foram feitas de 3 a 12 meses após a RT devido a doenças periodontais. Para os dentes irradiados in vitro, as amostras foram submersas em água destilada com uma irradiação total e única de 70 Gy. O estudo foi dividido em 2 fases independentes: Fase 1: Dentina Não-Restaurada (avaliação de amostras não irradiadas, dentes submetidos à radioterapia in vitro e in situ). Fase 2: Dentina Restaurada (avaliação de amostras não irradiadas e dentes submetidos à radioterapia in vitro) com 3 adesivos. Para o ensaio de zimografia (fase 1), os grupos irradiados in vitro, in vivo e não irradiados foram divididos em dois subgrupos: 1) mineralizado; 2) desmineralizado com ácido fosfórico10%. As proteínas dentinárias foram extraídas e submetidas à análise zimográfica de acordo com Mazzoni et al., 2007. Para a zimografia in situ (fase 2), os espécimes foram divididos em 6 grupos, de acordo com a forma de irradiação (não irradiada e irradiada in vitro) e o sistema adesivo testado (Adper Single Bond, 3M ESPE, ClearFil SE Bond, Kuraray ou Scotchbond Universal, 3M ESPE). Uma gelatina conjugada com fluoresceína autoextinguível foi usada como substrato para as proteases endógenas. A atividade enzimática gelatinolítica foi observada em microscópio confocal (Zeiss LSM 780-NLO, Carl Zeiss Microscopy GmbH). Para a análise da microscopia eletrônica de varredura, amostras restauradas e hígidas foram submetidas a técnica de pré-imunomarcação usando anticorpo monoclonal primário anti-CT-K e anti-CT-B, e anticorpo secundário conjugado com nano-partículas de ouro de 15nm. Um aumento na atividade gelatinolítica pós radioterapia para ambos os substratos (dentina restaurada e hígida) pôde ser observada. Houve uma maior expressão das formas ativas das MMP-2 e MMP-9 pós radioterapia para ambas as formas de radioterapia em dentina não restaurada. Nenhuma diferença na imuno-marcação para CT-K e CT-B entre os grupos irradiados e não irradiados foi observada. Adesivos autocondicionantes apresentaram uma imuno-marcação mais fraca para CT-K quando comparado ao adesivo de condicionamento total. Com isso, pode-se concluir que a radiação ionizante foi capaz de influenciar a atividade enzimática das proteínas endógenas da dentina restaurada e não restaurada. Palavras-chave: Radioterapia, metaloproteinases de matriz, MMP, cisteinocatepsinas, CT, Cárie relacionada à radiação. / Radiotherapy is one of the main treatments for head and neck cancer patients. Radiation-related caries and early restorations failures are side-effects with high rate of recurrence. As enzymatic degradation of collagen occurs mainly through the activity of matrix metalloproteinases (MMPs) and cysteine-cathepsins (CTs), the objective of this study was to evaluate the influence of in vivo and in vitro radiotherapy on endogenous proteases of the restored and non-restored dentin. In vivo irradiated teeth were extracted from patients who underwent clinical radiation protocols with a cumulative dose of radiation that ranged from 40 to 70 Gy. Extractions were performed 3 to 12 months after radiotherapy conclusion due to periodontal reasons. For the in vitro irradiated teeth, samples were submerged in distilled water with a total and single irradiation dose of 70 Gy. For gelatin zymography assay, irradiated in vivo, in vitro and non-irradiated groups were divided in two subgroups: 1) mineralized or 2) demineralized with 10% phosphoric acid. Dentin proteins were extracted and submitted to zymographic analysis in accordance to Mazzoni et al., 2007. For in situ zymography, specimens were divided into 6 groups, according to its irradiation form (non-irradiated and irradiated in vitro) and the adhesive system tested (Adper Single Bond, 3M ESPE, ClearFil SE Bond, Kuraray or Scotchbond Universal, 3M ESPE) using a self-quenched fluorescein-conjugated gelatin as the endogenous proteases substrate. The endogenous gelatinolytic enzyme activity was assessed by confocal laser-scanning microscope (Zeiss LSM 780-NLO, Carl Zeiss Microscopy GmbH). For SEM analysis of the HL, restored specimens were submitted to a pre-embedding immunolabeling technique using primary monoclonal antibody anti-CT-K and anti-CTB and a secondary antibody conjugated with 15nm gold nanoparticles. Radiotherapy groups presented increased gelatinolytic activity on both restored and non-restored dentin. MMP-2 and MMP-9 active form presented higher expression on both irradiated groups for non-restored dentin. Labeling for CT-K and CT-B did not differ from irradiated to non-irradiated groups. SE adhesives presenter weaker labeling for CT-K when compared to the E&R adhesive. Herewith, ionizing radiation may be able to influence the enzymatic activity of the endogenous proteins of restored and unrestored dentin

The aim of this study is to analyse a genetic and proteomic aspects that could play an important role in development of chosen cardiovascular disease. Matrix metalloproteinases are enzymes that contribute strongly to the degradation of extracellular matrix components. In this study the serological levels of MMP-2 and MMP-9 were investigated using immunological testing in patients with aortic valve disease and in patients with myocardial infarction. Significantly higher levels of MMP-2 and MMP-9 were determined in both above mentioned groups of patients. Association of serum levels of MMP-2 and MMP-9 and development of concomitant aortic dilatation was not confirmed in patients with aortic valve disease. Changes in serum levels within 24 hours and after 6 months post myocardial infarction were characterized. About 10 % of patients operated for aortic valve disease suffer simultaneously from ascending aortic dilatation. The current study did not reveal any significant genetic variation in TGFBR2 gene and in chosen exons of FBN1 gene in these patients. Further genetic research is needed to identify the cause of the pathology in aortic wall. Gene expression of selected genes was measured by microarray screening in patients with myocardial infarction. These genes were related to MMPs and did not show...

A endometriose é uma doença de origem multifatorial, caracterizada por presença de tecido endometrial fora da cavidade uterina, responsável por sintomas álgicos com grande impacto na qualidade de vida da paciente, além de ser um dos principais fatores de infertilidade. Muitos estudos já foram realizados no intuito de explicar a etiopatogenia da endometriose, assim como muito tem sido estudado para encontrar novas estratégias de tratamento. Várias linhas de medicamentos têm sido estudadas com este intuito, agindo em diferentes pontos da etiopatogênese da doença, uma delas na inibição de metaloproteinases da matriz extracelular, que tem papel no remodelamento do mesotélio do peritônio e angiogênese. O objetivo deste estudo foi avaliar a influência de uma droga (doxiciclina) de baixo custo, com ação conhecida na inibição das metaloproteinases, em endometriose peritoneal induzida em ratas. Para isso, foram usadas 30 ratas adultas Wistar com lesão induzida de endometriose, divididas em três grupos, um grupo controle (C, n=10) sem tratamento, um grupo onde foi administrado doxiciclina em baixa dose (BD, n=10) e um grupo onde foi realizado doxiciclina em alta dose (AD, n=10). Foi realizada avaliação da área das lesões de cada rata e estudo imunohistoquímico para positividade de anticorpo primário de metaloproteinase de matriz 9 (MMP9) e de inibidor de metaloproteinase de matriz 2 (TIMP2). A doxiciclina atuou reduzindo a área das lesões nos grupos BD e AD (p=0,0052) em relação ao grupo C e reduzindo a expressão do TIMP2 no grupo AD (p=0,0009) em relação aos grupos BD e C. Não houve resultado significativo na expressão da MMP9. / Endometriosis is a multifactorial origin disease, characterized by the presence of endometrial tissue outside the uterine cavity, responsible for painful symptoms with important impact on the life quality of the patient, besides being one of the main factors of infertility. Many studies have already been carried out to explain the etiopathogenesis of endometriosis, and much has been studied to find new treatment strategies. Several lines of drugs have been studied for this purpose, acting at different points in the etiopathogenesis of the disease, one of them in the inhibition of extracellular matrix metalloproteinases, which plays a role in the remodeling of the peritoneum mesothelium and angiogenesis. The purpose of this study was to evaluate the influence of a low-cost drug (doxycycline), with known action on the inhibition of metalloproteinases, in induced peritoneal endometriosis in rats. Thirty adult Wistar rats with endometriosis-induced lesions were divided into three groups: one untreated control group (C, n = 10), one group receiving low dose doxycycline (BD, n = 10) and a group where high dose doxycycline (AD, n = 10) was performed. An evaluation of the lesion area of each rat and immunohistochemical study for primary antibody to matrix metalloproteinase 9 (MMP9) and matrix metalloproteinase inhibitor 2 (TIMP2) was performed. Doxycycline worked by reducing the area of lesions in the BD and AD groups (p = 0.0052) in relation to the C group and reducing the expression of TIMP2 in the AD group (p = 0.0009) in relation to the BD and C groups. There was no significant effect on MMP9 expression in the present study.

Introdução: A hipertrofia cardíaca induzida por sobrecarga hemodinâmica crônica (HC) é caracterizada por espessamento das paredes do ventrículo esquerdo e do tecido intersticial. As atividades aumentadas de calpaína-1 e metaloproteinase de matriz(MMP)-2 são observadas em diferentes modelos de hipertensão arterial e estão relacionadas com as mudanças fisiopatológicas na HC. Por outro lado, a atividade de MMP-2 parece ser modulada positivamente por ativação de calpaína-1 em diferentes modelos. O objetivo deste trabalho é analizar se a calpaína-1 contribui para o aumento da atividade de MMP-2 no coração e se esse mecanismo resulta nas mudanças crônicas cardíacas na hipertensão renovascular. Métodos: Ratos Wistar submetidos ao modelo de 2-rins-1 clipe (2R-1C)(180-200g) e seus respectivos controles (Sham) foram tratados com verapamil (VRP), um bloqueador de canais para cálcio tipo L (BCCL, 8mg/kg/bid) ou veículo durante 8 semanas. O BCCL reduz as concentrações intracelulares de cálcio, o que leva à diminuição da ativação de calpaína-1, e então à possível modulação da atividade e expressão proteica de MMP-2. Pressão arterial sistólica (PAS) dos ratos foi monitorada durante 10 semanas de hipertensão por pletismografia de cauda. O ventrículo esquerdo (VE) foi analisado por histologia e ecocardiografia para avaliação das dimensões ventriculares. A atividade de calpaína-1 e MMP-2 foi avaliada por zimografia em gel. A expessão proteica de calpaína-1 e MMP-2 foi avaliada por western blot e imunofluorescência. Os corações foram submetidos à avaliação funcional por Langendorff. Todos os protocolos foram aprovados pelo Comitê de Ética em Pesquisa Animal da Faculdade de Medicina de Ribeirão Preto (43/2017). Resultados: Após 10 semanas, a PAS teve um aumento sustentado nos animais 2R-1C e o tratamento com VRP não foi capaz de reduzí-la em nenhum tempo de hipertensão. O peso corporal não apresentou diferença significativa entre os grupos. O grupo hipertenso teve um aumento da massa cardíaca quando comparado ao sham e o tratamento com verapamil reduziu esse parâmetro. A análise da espessura do ventrículo esquerdo demonstra que o VRP é capaz de reverter a HC induzida por sobrecarga pressórica nos animais hipertensos. Os animais 2R-1C apresentaram um aumento singificativo na expressão proteica e atividade de calpaína-1 e o VRP foi capaz de diminuir esses níveis. Foi observado aumento da atividade das isoformas de MMP-2 nos ratos 2R-1C quando comparados aos controles e o VRP foi capaz de reduzir a atividade da isoforma de 64kDa. A contratilidade cardíaca intrínseca dos animais 2R-1C sugere uma disfunção cardíaca quando comparados aos controles sham, embora a fração de ejeção desses animais esteja preservada. O VRP não foi capaz de alterar esses parâmetros. Conclusão: O VRP pode contribuir para a redução da hipertrofia cardíaca por diminuir a expressão proteica de calpaína-1 e MMP-2 na hipertensão renovascular. Apoio financeiro: Capes, CNPq, FAPESP / Introduction: The chronic hemodynamic overload-induced cardiac hypertrophy (CH) is characterized by thickening of the left ventricle walls and hypertrophy of the cardiomyocytes and interstitial tissue. Increased activity of calpain-1 and matrix metalloproteinase(MMP)-2 was observed in different models of arterial hypertension models and contributes to the pathophysiologic changes shown in CH. On the other hand, MMP-2 activity is also positively modulated by activation of calpain-1 in different animal models of cardiovascular diseases. The objectives here are to analyze whether calpain-1 contributes to increase the activity of MMP-2 in the heart and whether this mechanism results in chronic cardiac changes in the renovascular hypertension. Methods: Two kidney-one clip (2K1C) hypertensive male Wistar rats (180-200g) and their respective controls (Sham) were orally treated with verapamil (VRP), a L-type calcium channels blocker (LCCB, 8mg/kg/bid), or vehicle during 8 weeks. The LCCB reduces the intracellular concentration of calcium, thus decreasing the activation of calpain-1, and then may modulate the activity of MMP-2. Systolic blood pressure (SBP) was monitored in the rats during 10 weeks of hypertension. Left ventricle (LV) was analyzed by histology and echocardiography to evaluate ventricle thickening. Calpain- 1 and MMP-2 activities were analyzed by zymography and their expression by immunofluorescence and western blot. Hearts were submitted to functional evaluation by Langendorff. All the protocols were approved by the Ethical Committee in Animal Research of Ribeirao Preto Medical School (43/2017). Results: After 10 weeks, the systolic blood pressure had sustained increase and treatment with VRP was not able to decrease it in any time of hypertension. The body weight did not present significant changes between the groups. Hypertensive group had significant increase in the ventricle/body weight ratio (VW/BW) when compared to sham and treatment with VRP decreased it. Analysis of ventricle thickening showed that VRP is able to revert CHinduced pressure overload. The 2K-1C rats showed a significant increase in the activity and expression of calpain-1 in the heart and VRP reverted it. It was also observed increased activity of MMP-2 forms in the hypertensive rats and VRP decreased the 64kDa MMP-2 activity. The 2K-1C group had cardiac dysfunction when compared to controls groups, and VRP did not alter it. The ejection fraction was not changed in 2K- 1C rats. Conclusion: VRP decreased expression and activity of calpain-1 and MMP-2 in the hearts of 2K-1C rats and then contributed to ameliorate hypertension-induced cardiac hypertrophy

Introdução: A hipertrofia cardíaca induzida por sobrecarga hemodinâmica crônica (HC) é caracterizada por espessamento das paredes do ventrículo esquerdo e do tecido intersticial. As atividades aumentadas de calpaína-1 e metaloproteinase de matriz(MMP)-2 são observadas em diferentes modelos de hipertensão arterial e estão relacionadas com as mudanças fisiopatológicas na HC. Por outro lado, a atividade de MMP-2 parece ser modulada positivamente por ativação de calpaína-1 em diferentes modelos. O objetivo deste trabalho é analizar se a calpaína-1 contribui para o aumento da atividade de MMP-2 no coração e se esse mecanismo resulta nas mudanças crônicas cardíacas na hipertensão renovascular. Métodos: Ratos Wistar submetidos ao modelo de 2-rins-1 clipe (2R-1C)(180-200g) e seus respectivos controles (Sham) foram tratados com verapamil (VRP), um bloqueador de canais para cálcio tipo L (BCCL, 8mg/kg/bid) ou veículo durante 8 semanas. O BCCL reduz as concentrações intracelulares de cálcio, o que leva à diminuição da ativação de calpaína-1, e então à possível modulação da atividade e expressão proteica de MMP-2. Pressão arterial sistólica (PAS) dos ratos foi monitorada durante 10 semanas de hipertensão por pletismografia de cauda. O ventrículo esquerdo (VE) foi analisado por histologia e ecocardiografia para avaliação das dimensões ventriculares. A atividade de calpaína-1 e MMP-2 foi avaliada por zimografia em gel. A expessão proteica de calpaína-1 e MMP-2 foi avaliada por western blot e imunofluorescência. Os corações foram submetidos à avaliação funcional por Langendorff. Todos os protocolos foram aprovados pelo Comitê de Ética em Pesquisa Animal da Faculdade de Medicina de Ribeirão Preto (43/2017). Resultados: Após 10 semanas, a PAS teve um aumento sustentado nos animais 2R-1C e o tratamento com VRP não foi capaz de reduzí-la em nenhum tempo de hipertensão. O peso corporal não apresentou diferença significativa entre os grupos. O grupo hipertenso teve um aumento da massa cardíaca quando comparado ao sham e o tratamento com verapamil reduziu esse parâmetro. A análise da espessura do ventrículo esquerdo demonstra que o VRP é capaz de reverter a HC induzida por sobrecarga pressórica nos animais hipertensos. Os animais 2R-1C apresentaram um aumento singificativo na expressão proteica e atividade de calpaína-1 e o VRP foi capaz de diminuir esses níveis. Foi observado aumento da atividade das isoformas de MMP-2 nos ratos 2R-1C quando comparados aos controles e o VRP foi capaz de reduzir a atividade da isoforma de 64kDa. A contratilidade cardíaca intrínseca dos animais 2R-1C sugere uma disfunção cardíaca quando comparados aos controles sham, embora a fração de ejeção desses animais esteja preservada. O VRP não foi capaz de alterar esses parâmetros. Conclusão: O VRP pode contribuir para a redução da hipertrofia cardíaca por diminuir a expressão proteica de calpaína-1 e MMP-2 na hipertensão renovascular. Apoio financeiro: Capes, CNPq, FAPESP / Introduction: The chronic hemodynamic overload-induced cardiac hypertrophy (CH) is characterized by thickening of the left ventricle walls and hypertrophy of the cardiomyocytes and interstitial tissue. Increased activity of calpain-1 and matrix metalloproteinase(MMP)-2 was observed in different models of arterial hypertension models and contributes to the pathophysiologic changes shown in CH. On the other hand, MMP-2 activity is also positively modulated by activation of calpain-1 in different animal models of cardiovascular diseases. The objectives here are to analyze whether calpain-1 contributes to increase the activity of MMP-2 in the heart and whether this mechanism results in chronic cardiac changes in the renovascular hypertension. Methods: Two kidney-one clip (2K1C) hypertensive male Wistar rats (180-200g) and their respective controls (Sham) were orally treated with verapamil (VRP), a L-type calcium channels blocker (LCCB, 8mg/kg/bid), or vehicle during 8 weeks. The LCCB reduces the intracellular concentration of calcium, thus decreasing the activation of calpain-1, and then may modulate the activity of MMP-2. Systolic blood pressure (SBP) was monitored in the rats during 10 weeks of hypertension. Left ventricle (LV) was analyzed by histology and echocardiography to evaluate ventricle thickening. Calpain- 1 and MMP-2 activities were analyzed by zymography and their expression by immunofluorescence and western blot. Hearts were submitted to functional evaluation by Langendorff. All the protocols were approved by the Ethical Committee in Animal Research of Ribeirao Preto Medical School (43/2017). Results: After 10 weeks, the systolic blood pressure had sustained increase and treatment with VRP was not able to decrease it in any time of hypertension. The body weight did not present significant changes between the groups. Hypertensive group had significant increase in the ventricle/body weight ratio (VW/BW) when compared to sham and treatment with VRP decreased it. Analysis of ventricle thickening showed that VRP is able to revert CHinduced pressure overload. The 2K-1C rats showed a significant increase in the activity and expression of calpain-1 in the heart and VRP reverted it. It was also observed increased activity of MMP-2 forms in the hypertensive rats and VRP decreased the 64kDa MMP-2 activity. The 2K-1C group had cardiac dysfunction when compared to controls groups, and VRP did not alter it. The ejection fraction was not changed in 2K- 1C rats. Conclusion: VRP decreased expression and activity of calpain-1 and MMP-2 in the hearts of 2K-1C rats and then contributed to ameliorate hypertension-induced cardiac hypertrophy

Made available in DSpace on 2017-07-21T19:59:58Z (GMT). No. of bitstreams: 1 Kamila Caroline Camargo.pdf: 3696475 bytes, checksum: 886b21796d7054b1ce4963cb6ea656e9 (MD5) Previous issue date: 2013-03-26 / Membrane type I MMP (MT1-MMP) is involved in cellular adhesion, proliferation, migration and cell death during organogenesis and adult phase of vertebrates. However, its role in the development of the small intestinal has not been established. We formulated the hypothesis that this metalloproteinase would play a relevant role in the development of the intestinal mucosa. To assess this hypothesis was detected the labeling of MT1-MMP by immunohistochemistry in the intestinal mucosa along the pre-and postnatal development of rats and chickens so that from a comparative analysis, it were possible infer about the role of this metalloproteinase.In thepre natal phase of rats, the labeling of MT1-MMP correlates with events that lead to morphogenesis of villi and establishment of the tecidual homeostasis. In the pre natal phase of chickens, the labeling of MT1-MMP correlates with events that lead to growth of the intestine. In the postnatal phase of rats and chickens, the labeling of MT1-MMP was maintained in the intestinal mucosa, which led us to suggest that this metalloproteinase have a relevant role in the tecidual homeostasis throughout adulthood.We suggest that the role of that MT1-MMPin the remodeling and growth of the intestinal mucosa of rats and chickens is related with adhesion, proliferation, migration and death of epithelial cells and migration of mesenchymalcells. This is the first work that evidence the MT1-MMP in the small intestine of vertebrates during development, making it possible that further studies willclarify its role in the formation of this important organ. / A metaloproteinase de membrana 1 (MT1-MMP) é envolvida em processos de adesão proliferação, migração celular e morte celular durante a organogênese e na fase adulta de vertebrados. Entretanto, o seu papel no desenvolvimento do intestino delgado de vertebrados ainda não foi estabelecido. Nós formulamos a hipótese de que essa metaloproteinase de membrana teria um papel relevante no processo de desenvolvimento da mucosa intestinal. Para avaliar essa hipótese, detectou-se a marcação da MT1-MMP por imunohistoquímica na mucosa intestinal ao longo do desenvolvimento pré e pós-natal de ratos e galinhas para que, a partir de uma análise comparativa, fosse possível inferir a respeito do papel dessa metaloproteinase. No período pré-natal de ratos, a marcação da MT1-MMP correlaciona com eventos que levam à morfogênese das vilosidades e estabelecimento da homeostase tecidual. No período pré-natal de galinhas, a marcação da MT1-MMP correlaciona com eventos que levam ao crescimento do intestino. No período pós-natal de ratos e galinhas, a marcação da MT1-MMP foi mantida no epitélio intestinal, o que nos levou a sugerir que essa metaloproteinase tem um papel importante na homeostase tecidual durante toda a vida adulta.Nós sugerimos que o papel da MT1-MMPna remodelação e crescimento da mucosa intestinal de ratos e galinhas está relacionado com adesão, proliferação, migração e morte de células epiteliais e migração de células mesenquimais. Esse é o primeiro trabalho que evidencia a MT1-MMP no intestino delgado de vertebrados durante o desenvolvimento, possibilitando estudos subsequentes que venham a esclarecer o papel dessa metaloproteinase na formação desse importante órgão.

Au cours de la réparation cutanée, l’étape de réépithélialisation est essentielle car son objectif est de restaurer la fonction barrière de la peau. Elle consiste en une série d’étapes coordonnées où les kératinocytes migrent, prolifèrent et se différencient jusqu’à restauration complète de l’épiderme. Régulée de façon simultanée au niveau intracellulaire mais également extracellulaire, elle dépend de la production de facteurs de croissance, de métalloprotéases matricielles (MMPs) et de protéines de la matrice extracellulaire sur lesquelles les kératinocytes adhèrent et migrent par l’intermédiaire de récepteurs de la famille des intégrines ou des syndécans. Parmi les ligands matriciels, la laminine 332 (LN332), qui est connue comme étant la protéine d’adhésion majeure des kératinocytes de l’épiderme, s’avère être également impliquée au cours de la réépithélialisation et jouer un rôle important dans les processus d’adhésion et de migration des kératinocytes, notamment par le biais de son domaine globulaire LG4/5 localisé à l’extrémité C-term de sa chaine 3. De récentes études ont montré que ce domaine LG4/5 induit la migration des kératinocytes normaux humains (NHK), impliquant des MMPs pro-migratoires MMP-1 et MMP-9. Puisque les domaines LG4/5 ont été montrés comme participant à la dynamique du cytosquelette et au mouvement cellulaire par le biais des récepteurs syndécan-1 et -4, mon laboratoire d’accueil a décidé d’étudier l’implication du récepteur syndécan-1 dans ce processus d’expression de la MMP-9. Les analyses PCR et les résultats de zymographie obtenus ont révélé que le syndécan-1 joue un rôle dans l’expression et l’activation de la MMP-9 induite par le domaine LG4/5. De plus, la déplétion de l’expression du syndécan-1 dans les NHK a confirmé ces résultats. De précédents résultats de mon laboratoire d’accueil ont montré que le domaine LG4/5 induit la formation de filopodes médiée par le syndécan-1 au niveau du front de migration des kératinocytes. De ce fait, nous avons effectué des zymographies de gélatine in situ chez des NHK en migration afin d’observer la localisation de la MMP-9 et de savoir si cette dernière était trouvée au niveau de ces structures d’adhésion protrusives. Nous avons observé des zones de digestion de gélatine sous les NHK ressemblant à des points de contact d’adhésion. Leur nombre est augmenté chez des NHK traités avec le domaine LG4/5 de la LN332. L’utilisation d’inhibiteurs spécifiques des gélatinases et de la MMP-9 ont révélé que cette dernière est responsable de la formation de ces zones de digestion de gélatine. Parce que ces structures évoquent des podosomes, nous avons décidé de révéler leurs constituants majoritaires, à savoir la cortactine, la vinculine, l’-actinine, VASP, WASP ou encore Arp2/3. Dans le même temps nous avons également révélé le syndécan-1 afin de voir si ce dernier était présent dans ces structures. Nos résultats ont montré que tous les marqueurs des podosomes étaient localisés soit sous la forme d’un point à l’intérieur des zones de digestion pour les protéines régulatrices de l’actine, soit sous la forme d’un anneau entourant les zones de digestion pour les protéines d’adhésion et de signalisation associées à la membrane, confirmant donc que les structures observées sont bien des podosomes. Le syndécan-1 apparaît également sous une forme d’anneau, entourant les protéines régulatrices de l’actine et les zones de digestion laissant penser que le syndécan-1 serait impliqué dans ces structures. La diminution de l’expression du syndécan-1, en utilisant l’approche des petits ARN interférents dans des NHK, a montré que l’absence de syndécan-1 diminue de façon drastique le nombre et la surface des zones digérées. L’ensemble de nos résultats montre que le syndécan-1 serait un constituant des podosomes des kératinocytes, participant à leur formation et jouant un rôle dans le contrôle de l’expression de la MMP-9 / During skin repair, the reepithelialization step is essential to restore the skin barrier function. lt occurs by an orderly series of events whereby keratinocyte migrate, proliferate and differentiate until complete epidermal restoration. Keratinocyte migration determines the efficiency of the overall wound repair process. The keratinocyte's migratory behavior depends on the production of growth factors, matrix metalloproteinases (MMP) and on the dynamic interactions of the cells with extracellular components. Laminin 332 (LN332), known as a major adhesion substrate for keratinocytes, was shown to contribute to skin reepithelialization through its a3 chain C-terminal domains LG4/5. Recent studies have reported that LG4/5 induces keratinocyte migration, an event that relies on the involvement of the pro-migratory MMP-1 and MMP-9. As LG4/5 domains were shown to participate in cytoskeleton dynamic and cell movement through binding of the heparan sulfate proteoglycans syndecan-1 and -4, we analyzed the potential involvement of these receptors in this process. The PCR analysis and zymography results revealed that syndecan-1 plays a role in LG4/5 induced MMP-9 expression and activation. Down regulating or overexpressing syndecan-1 expression in cells confirmed these findings. As LG4/5 was shown to induce the formation of syndecan-1-mediated filopodia at the front of migrating cells, we performed in situ zymography experiments in migrating keratinocyte to analyze whether MMP-9 is found in these protrusive adhesion structures. Very interestingly, we found areas of digested gelatin resembling adhesion contacts underneath keratinocytes. Their number was increased in LG45-treated keratinocytes, a result in line with our previous data. The use of specific MMP inhibitors revealed that MMP-9 is responsible for the formation of these digested gelatin clusters. Further confocal microscope analysis revealed, at the cellular level, the presence of actin located within the digested areas, suggesting that an adhesion receptor would be involved in this process. Because these structures resemble podosomes, we revealed major podosome components, such as cortactin, vinculin, -actinin, VASP, WASP, Arp2/3 or dynamin and integrin. Our results showed all the podosome markers either within the digested areas (regulatory actin proteins) or organized as ring encircling the digested areas (signaling and adhesion proteins associated with plasma membrane), confirming that these structures are podosomes. Syndecan-1 also appears as a ring around the digested areas and encircling the regulatory actin proteins, suggesting that this receptor could be involved in these structures. The syndecan-1 depletion in normal human keratinocytes with specific siRNAs drastically decreased the digested areas surface. Taken together, our data demonstrate that syndecan-1 is a podosome components, participating in their formation and playing a role in MMP-9 expression and deposition. These results suggest that its re-distribution at the front edge of migrating keratinocyte may have a role to play in the cleavage or degradation of extracellular matrix proteins therefore facilitating their path through the fibrin clot