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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Estudo dos polimorfismos genéticos da metalproteinase de matriz 2 envolvidos na carcinogênese cervical

QUIXABEIRA, Dafne Carolina Alves 25 February 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-05-25T14:19:45Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação_Dafne_C_A_Quixabeira.pdf: 2494498 bytes, checksum: df9aad949df97edff70e2580bdd977c5 (MD5) / Made available in DSpace on 2017-05-25T14:19:45Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação_Dafne_C_A_Quixabeira.pdf: 2494498 bytes, checksum: df9aad949df97edff70e2580bdd977c5 (MD5) Previous issue date: 2016-02-25 / CAPES / CNPQ / FACEPE / O câncer de colo do útero apresenta distribuição a nível mundial, correspondendo ao quarto mais incidente entre as mulheres. Está associado à infecção prévia pelo Papillomavírus Humano (HPV) em quase a totalidade dos casos. Diversos cofatores atuam em consonância ao HPV para o surgimento de lesões cervicais e posterior carcinoma. Importante destaque como cofator deve ser dado às metaloproteinases de matriz (MMP), enzimas proteolíticas que participam da lise tanto de componentes da matriz extracelular (MEC), como os que não pertencem a matriz. Particularmente a MMP-2 tem destaque relevante no câncer cervical, por favorecer a progressão de lesões in situ para a invasão ao lisar a membrana basal. Polimorfismos na região promotora desse gene têm sido associados ao aumento do risco da progressão do câncer e formação de metástases. O objetivo do presente trabalho foi avaliar a possível associação dos polimorfismos de base única (SNP) -1306C/T e -735C/T, presentes na região promotora do gene da MMP-2 em lesões cervicais em mulheres de dois Estados da região Nordeste do Brasil. Foram avaliados 52 casos de lesões intraepiteliais de baixo grau (LSIL) e 67 lesões intraepiteliais de alto grau (HSIL) para o polimorfismo -1306 C/T. Enquanto que 63 casos de LSIL e 73 casos de HSIL foram selecionados para a avaliação do SNP 735C/T. 95 casos com citologia normal foram selecionados como grupo controle do -1306C/T e 91 casos para o -735 C/T. A amplificação gênica e posterior genotipagem foram feitas por meio de PCR-RFLP, com o uso das enzimas Pvu II e Hinf I, para os SNP-1306C/T e -735C/T, respectivamente. A MMP-2 C1306T não apresentou associação significativa entre os grupos LSIL e o controle (p=0,1734OR=0.37; 95 % CI=0.3-1.58). Assim como entre os grupos controle e HSIL (p=0,7118 OR=0.08; 95 % CI=0.93-3.3). O mesmo foi observado para a avaliação do MMP-2 C735T, pois não foi encontrada associação significativa entre o grupo LSIL e o controle (p=0,7948; OR=0,94; 95 % CI=0,56-2,15), bem como entre o grupo HSIL e o controle (p=0,7398; OR=1,07; 95 % CI=0,50-1,64). A presença do genótipo TT no modelo recessivo apresentou-se como fator protetor da progressão das lesões cervicais (p=0,03566; OR=0,66; 95 % CI=0,10-0,96). Em relação ao uso de contraceptivo oral como cofator, não foram encontradas associações, tanto entre os casos LSIL (p=0,370 OR=0.65; 95 % CI=0.35-1.93) e HSIL (p=0,6527; OR=0.08; 95 % CI=0.93-3.3) -1306C/T, quanto para os casos LSIL (p=0,57649; OR= 0,9; 95% CI=0.60-2.54) e HSIL (p=0,6269; OR= 0,74; 95% CI=0.47-1.57) do -735C/T. A associação entre a infecção pelo HPV e os genótipos C735T e C1306T não foi significativa (p >0,05). No presente estudo, apenas a presença do genótipo TT do MMP-2 C735T apresentou relevância estatística como fator protetor da progressão das lesões cervicais para a malignidade. / Cervical cancer is a global health problem being the fourth most incident cancer in women. This type of cancer is associated with prior infection with Human Papillomavirus (HPV) in almost all cases. Some cofactors act with HPV in the development of lesions and posterior cervical carcinoma. An important cofactor are matrix metalloproteinases (MMP). Proteolytic enzymes that participate in the lysis component of the extracellular matrix (ECM). Particularly MMP-2 excels in cervical cancer progression by promoting the intraepithelial lesions to invasion due to lysis of the basal membrane. Polymorphisms in the promoter region of the MMP-2 gene has been associated with increased risk of progression to cancer and metastasis. This study aimed to evaluate the possible association of single nucleotide polymorphisms (SNP) -1306C / T and 735C / T, present in the promoter region of the MMP-2 gene in cervical lesions in women in States of northeastern Brazil. We evaluated 52 cases of low grade intraepithelial lesions (LSIL) and 67 cases of high grade (HSIL) for the polymorphism -1306 C/T. While other 63 LSIL cases and 73 HSIL cases were evaluated for SNP -735C/T. 95 cases with normal cytology were selected with the control group -1306C / T and 91 cases for the -735 C / T. Gene amplification and subsequent genotyping were performed by PCR-RFLP. For this we used the restriction enzyme Pvu II (for SNP-1306C / T) and Hinf I (for SNP -735C / T). The MMP-2 C1306T showed no significant association between the LSIL group and the control (p = 0,1734OR = 0:37; 95% CI = 0.3-1.58). As well as between the control group and HSIL (p = 0.7118 OR = 0:08; 95% CI = 0.933.3). The same was observed for the evaluation of MMP-2 compared C735T LSIL group and the control group (p = 0.7948, OR = 0.94; 95% CI = 0.56 to 2.15). There was also no association between HSIL group and the control (p = 0.7398; OR = 1.07; 95% CI = 0.50 to 1.64). The presence of the TT genotype in recessive model was presented as a protective factor in the progression of cervical lesions (p = 0.03566; OR = 0.66; 95% CI = .10-.96). Regarding the use of oral contraceptive as a cofactor, no significant associations found between LSIL cases (p = 0.370 OR = 0.65; 95% CI = 0.35-1.93) and HSIL (p = 0.6527; OR = 0:08; 95% CI = 0.93-3.3) from -1306C / T group, as well as LSIL (p = 0.57649; OR = 0.9; 95% CI = 0.60-2.54) and HSIL (p = 0.6269, OR = 0 74; 95% CI = 0:47 to 1:57) of -735C / T group. The association between HPV infection and the C735T and C1306T genotypes was not significant (p> 0.05). In the present study, only the presence of the TT genotype of MMP-2 C735T showed statistically significant protective factor in the progression of cervical lesions to malignancy.
102

Interação toxicogenética de polimorfismos da metaloproteinase-9 (MMP-9) da matriz extracelular e exposição ao mercúrio = efeitos sobre a atividade plasmática da MMP-9 / Toxicogenetic relevance of MMP-9 polymorphisms in mercury exposed subjects

Ferreira, Anna Laura Bechara Jacob 07 January 2010 (has links)
Orientador: José Eduardo Tanus dos Santos / Tese (doutorado) - Universidade Estadual de Campinas. Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-16T09:07:18Z (GMT). No. of bitstreams: 1 Ferreira_AnnaLauraBecharaJacob_D.pdf: 12479529 bytes, checksum: a0414f163dce135319bdfb549308977a (MD5) Previous issue date: 2010 / Resumo: A exposição ao mercúrio (Hg) causa efeitos deletérios à saúde, incluindo doenças cardiovasculares. Embora os mecanismos não estejam precisamente definidos, metaloproteinases (MMPs) -2 e -9 podem estar envolvidas. Expressão e atividades aumentadas destas MMPs são demonstradas em diversas condições patológicas, e estudos demonstraram que os níveis circulantes de MMPs poderiam ser usados como marcadores de risco cardiovascular. O gene que codifica a MMP-9 apresenta polimorfismos que afetam a expressão e o nível de atividade desta enzima, sendo que dois deles, presentes na região promotora [C- 1562T e (CA)n], são funcionalmente importantes, tendo sido associados a diversas doenças. Investigamos se existe associação entre os níveis circulantes de MMP-2, MMP-9 e seus inibidores endógenos (TIMPs) -2 e -1 com os níveis circulantes de Hg, em indivíduos expostos ao metal por consumo de peixes, na Amazônia Brasileira. Em seguida, examinamos se os polimorfismos da MMP-9 afetam os níveis circulantes de MMP-9, nestes indivíduos. Para isso, analisamos as concentrações de Hg no sangue e plasma desses indivíduos por espectrometria de massas com plasma indutivamente acoplado (ICP-MS). As concentrações de MMPs e TIMPs foram medidas nas amostras de plasma por zimografia e ELISA, respectivamente. Espécies reativas ao ácido tiobarbitúrico (TBARS) foram medidas no plasma, para dosar estresse oxidativo. Os níveis de selênio (Se) foram determinados por ICP-MS, por este ser um antioxidante. O DNA genômico foi extraído das amostras de sangue e os genótipos dos polimorfismos C- 1562T e (CA)n foram determinados. A relação entre os bioindicadores de Hg e os níveis de MMPs, assim como a relação entre os genótipos da MMP-9 e os níveis de MMP-9 foram examinados usando modelos de regressão múltipla. Não foi encontrada relação entre Hg no sangue ou plasma e MMPs. Contudo, Hg no plasma foi negativamente associado com os níveis de TIMPs, resultando em aumento nas razões MMP-9/TIMP-1 e MMP-2/TIMP-2, o que indica uma associação positiva entre Hg no plasma e o grau de atividade de MMP-9 e MMP-2. Os polimorfismos da MMP-9 não se relacionaram aos níveis de MMP-9 quando todos os indivíduos foram analisados juntos. No entanto, quando dividimos a população estudada em terços, com base nas concentrações plasmáticas de Hg, o polimorfismo (CA)n afetou o grau de atividade da MMP-9 no grupo com níveis mais baixos de Hg no plasma. Os níveis de MMP-9 foram mais altos em pessoas com genótipos que incluíam o alelo com mais de 21 repetições CA (alelos H), e menos naqueles cujo genótipo incluía alelos com menos de 21 repetições CA (alelos L). Nos grupos com níveis intermediários ou altos de Hg no plasma, este polimorfismo não teve efeito. Nenhuma associação foi encontrada entre o polimorfismo C- 1562T e os níveis de MMP-9, nos três grupos. Esses achados mostram o efeito do Hg sobre o grau de atividade de MMPs,e que o efeito do Hg sobre a MMP-9 é modulado pelo polimorfismo (CA)n da MMP- 9. O aumento do grau de atividade poderia aumentar o risco de desenvolvimento de doenças cardiovasculares em pessoas expostas ao Hg, principalmente nas que apresentam o genótipo HH. / Abstract: Mercury (Hg) exposure causes health problems, including cardiovascular diseases. Although the mechanisms are not precisely defined, metalloproteinases (MMP) -2 and -9 may be involved. Increased expression and activities of these MMPs are demonstrated in several pathological conditions, and recent studies have demonstrated that circulating levels of MMPs could be used as a blood-borne biomarker for cardiovascular risk, even in healthy individuals. The gene encoding MMP-9 presents genetic polymorphisms which affects the expression and activity level of this enzyme, two of them, present in the promoter region [C- 1562T and (CA)n] are functionally relevant, having been involved in several diseases. We investigated if the association between circulating levels of MMP-2, MMP- 9 and their endogenous inhibitors (TIMPs) -2 and -1 with circulating levels of Hg in individuals exposed to metal through consumption of fish in the Brazilian Amazon. Then, we examined whether these MMP-9 polymorphisms affect circulating MMP-9 net levels in persons exposed to mercury. For this purpose, we analyzed the concentrations of blood and plasma Hg by inductively coupled plasma-mass spectrometry (ICP-MS). MMPs and TIMPs concentrations were measured in plasma samples by zymography and ELISA, respectively. Thiobarbituric acid-reactive species (TBARS) were measured in plasma to assess oxidative stress. Selenium (Se) levels were determined by ICPMS, because it is an antioxidant. Genomic DNA was extracted from whole blood, and genotypes for the C- 1562T and the microsatellite (CA)n polymorphisms were determined. The relationships between biomarkers of Hg and MMPs levels, as well as the relationship between MMP-9 genotypes and MMP-9 levels, were examined using multivariate regression models. No relationship was found between Hg in blood or plasma and MMPs. However, plasma Hg levels were negatively associated with TIMPs levels, and thereby with increasing MMP-9/ TIMP-1 and MMP-2/TIMP-2 ratios, thus indicating a positive association between plasma Hg and circulating net MMP-9 and MMP-2 activities. The polymorphisms of MMP-9 were not related to MMP-9 net levels when all subjects were analyzed together. However, when we divided the population into tertiles of plasma Hg concentrations, the polymorphism (CA)n affected MMP-9 concentrations and MMP-9/TIMP-1 ratios in people with lower levels of Hg. MMP-9 levels were higher in persons with genotypes including alleles with more than 21 CA repeats (H alleles) and lower in those whose genotype including alleles with less than 21 CA repeats (L alleles). Conversely, this polymorphism had no effects in persons with intermediate or high plasma Hg level. No association was found between the C-1562T polymorphism and MMP-9 levels in the three groups. These findings show the effect of Hg on MMP-9 net, and that this effect is modulated by the (CA)n polymorphism of MMP-9. The increase in MMPs levels could increase the risk of developing cardiovascular diseases in persons exposed to Hg, especially those with HH genotype. / Doutorado / Doutor em Farmacologia
103

Associação de polimorfismos da metaloproteinase-9 de matriz extracelular com a susceptibilidade A e resposta farmacológica de pacientes com pré-eclâmpsia/hipertensão arterial gestacional / Association of matrix metalloproteinase (MMP)-9 polymorphisms with the susceptibility and drug responsiveness in patients with preeclampsia or gestacional hypertension

Palei, Ana Carolina Taveiros 17 August 2018 (has links)
Orientador: José Eduardo Tanus dos Santos / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-17T08:56:03Z (GMT). No. of bitstreams: 1 Palei_AnaCarolinaTaveiros_D.pdf: 6616764 bytes, checksum: 3e220ef5f104375086227af04101b5d6 (MD5) Previous issue date: 2010 / Resumo: A pré-eclâmpsia é uma síndrome caracterizada por hipertensão associada à proteinúria. As metaloproteinases de matriz extracelular (MMPs) são enzimas zinco-dependentes que degradam vários componentes da matriz extracelular, cuja atividade é modulada pelos inibidores teciduais de metaloproteinases (TIMPs). Uma vez que as MMP-2 e MMP-9 são fundamentais para os processos de formação e remodelamento dos tecidos feto-placentários e participam da regulação do tônus vascular, os níveis dessas enzimas podem estar alterados em desordens hipertensivas da gestação. É possível ainda que polimorfismos localizados no gene da MMP-9 possam influenciar na susceptibilidade a essas doenças. Logo, os objetivos desse trabalho foram: 1) comparar as concentrações plasmáticas de MMP-2, MMP-9, TIMP-1 e TIMP-2 entre grávidas saudáveis (GS), grávidas com hipertensão arterial gestacional (HAG) e com pré-eclâmpsia (PE); 2) comparar as frequências genotípicas e haplotípicas dos polimorfismos C-1562 T e (CA)n da MMP-9 entre GS, HAG e PE. E ta mbém correlacionar as concentrações de MMP-9 aos genótipos e haplótipos da MMP-9; 3) comparar as frequências genotípicas e haplotípicas desses polimorfismos entre HAG ou PE que respondem ou não à farmacoterapia com anti-hipertensivos. Inicialmente, determinaram-se os níveis de pro-MMP-9 e pro-MMP-2 no plas ma, por zimografia, e as concentrações plasmáticas de TIMP-1 e TIMP-2 nos grupos GS, HAG e PE, por ELISA. Nossos resultados revelaram um aumento da atividade líquida de MMP-9 (relação pro-MMP-9/TIMP-1) em HAG, mas em PE, comparados com GS. Em seguida, extraiu-se o DNA das voluntárias GS, HAG e PE, e determinaram-se as frequências genotípicas dos polimorfismos C-1562 T e (CA)n, por PCR seguida de eletroforese, e as frequências haplotípicas, pelo programa PHASE. Observou-se que o genótipo CT para o polimorfismo C-1562 T e o haplótipo H4 (T H) estão mais frequentes em HAG, mas não em PE, comparados com GS. Quando avaliamos as concentrações plasmáticas de MMP-9 segundo as distribuições genotípicas e haplotípicas, não se observam diferenças estatisticamente significantes nos grupos GS e PE, apesar de que o genótipo LH do polimorfismo (CA)n foi associado positivamente com a concentração de MMP-9 em HAG. Por último, determinaram-se as frequências genotípicas e haplotípicas nas pacientes HAG e PE classificadas conforme a responsividade à metildopa ou à terapia anti-hipertensiva total. Verificamos que os genótipos CT+TT estão mais freqüentes nas pacientes HAG que não respondem aos anti-hipertensivos, comparadas com as HAG responsivas, em ambas as abordagens. O haplótipo H2 (C H) está mais frequente nas HAG responsivas à terapia total, enquanto o haplótipo H4 nas HAG não-responsivas à terapia total. Além disso, verificou-se que haplótipo H2 está mais frequente nas pacientes PE que não respondem aos anti-hipertensivos em ambas as abordagens, comparadas com as PE responsivas. Portanto, nossos resultados sugerem que a MMP-9 apresenta um papel relevante na fisiopatologia da HAG e que o polimorfismo C-1562 T e o haplótipo H4 estão associados com a susceptibilidade e com a não-responsividade à terapia anti-hipertensiva dessa doença. E ainda que o haplótipo H2 está associado com a não-responsividade aos anti-hipertensivos em PE / Abstract: Preeclampsia is a syndrome characteriz ed by hypertension plus proteinuria. Matrix metalloproteinases (MMPs) are zinc-dependent enzymes that break down several extracellular matrix components, whose activity is modulated mainly by tissue inhibitors of metalloproteinases (TIMPs). Since MMP-2 and MMP-9 ar e essential for the processes of placental and uterine artery remodeling, and they can participate in vascular tone control, levels of these enzymes may be altered in hypertensiv e disorders of pregnancy. It is also possible that polymorphisms in the MMP-9 gene may influence susceptibility to t hese diseases. Thus, the objectives of this study were: 1) to compare plasma MMP-2, MMP-9, TIMP-1 and TIMP-2 concentrations among healthy pregnant (HP), pregnant women with gestational hypertension (GH) and preeclampsia (PE); 2) to compare the genotype and haplotype frequencies of MMP-9 polymorphisms (C T and (CA)n) among HP, GH and PE. And to correlate the MMP-9 concentrations with MMP-9 genotypes and haplotypes too; 3) to compare genotype and haplotype frequencies of these polymorphisms between GH or PE who respond or non-respond to pharmacotherapy with antihypertensives. To achieve our first goal, we determined the plasma pro-MMP-9 and pro-MMP-2 leve ls by zymography, and plasma TIMP-1 and TIMP-2 concentrations by ELISA in GS, HAG and PE. Ou r results showed a net increase in the MMP-9 activity (ratio pro-MMP-9/TIMP-1) in GH, but not in PE, compared with HP. Moreover, to achieve ou r second goal, we firstly extracted DNA from HP, GH and PE volunteers, and then we determined the genotype frequencies of C T and (CA)n polymorphisms by PCR followed by electrophoresis, and the haplotype fr equencies by the program PHASE. It was observed that CT genotype for the C T polymorphism and H4 haplotype (T H) are more frequent in GH, but not in PE, compared with the HP. When we evaluated plasma MMP-9 concentrations according to genotype and haplotype distributions, no statistically significant differences were observed in HP and GH groups; although the LH genotype for (CA) n polymorphism was associated significantly and positively with GH. To approach our third goal, we determined the genotype and haplotype frequenc ies in GH and PE patients classified as responsiveness to methyldopa or to glo bal antihypertensive treatment. We found -1562 -1562 -1562 that CT+TT genotypes are more frequent in GH patients who do not respond to antihypertensives in both approaches, compared with GH who respond. We also found that H2 haplotype (C H) is more common in GH women Who respond to global therapy, and that H4 hap lotype is more common in GH women who do not respond to global therapy. In addi tion, it was found he haplotype H2 are more frequent in PE patients who do not respond to antihypertensives in both approaches, compared with PE who respond. Therefore, our results suggest that MMP-9 has a role in the pat hophysiology of GH and the C T polymorphism and H4 haplotype are associ ated with susceptibility and non-responsiveness to antihypertensive treatment of this disease. While the H2 haplotype is associated with non-responsiveness to antihypertensives in PE / Doutorado / Doutor em Farmacologia
104

Associação entre haplótipos de metaloproteinase-9 de matriz extracelular (MMP-9) e obesidade infantil = efeitos sobre a concentração plasmática de MMP-9 / Association between haplotypes of matrix metalloproteinase-9 extracellular matrix (MMP-9) and childhood obesity : effects on plasma concentration of MMP-9

Belo, Vanessa de Almeida 17 August 2018 (has links)
Orientador: José Eduardo Tanus dos Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-17T23:52:34Z (GMT). No. of bitstreams: 1 Belo_VanessadeAlmeida_M.pdf: 3576019 bytes, checksum: c9ba06079f310fba660d5bfb890b000a (MD5) Previous issue date: 2011 / Resumo: A obesidade em crianças e adolescentes constitui-se num importante fator de risco para doenças cardiovasculares, em especial, aterosclerose. Esta condição é caracterizada por acúmulo de lipídeos e elementos fibrosos em artérias de grande calibre em que mecanismos inflamatórios e remodelamento vascular estão envolvidos. Neste contexto, a metaloproteinase-9 de matriz extracelular (MMP-9) - endopeptidase capaz de degradar componentes da matriz extracelular - e seu inibidor endógeno preferencial, inibidor tecidual de MMP (TIMP-1) são importantes mediadores deste remodelamento e um equilíbrio entre MMP-9 e TIMP-1 deve existir a fim de manter a integridade do sistema cardiovascular. Ademais, níveis aumentados de MMP-9 são observados em pacientes com doenças cardiovasculares e estudos genéticos têm mostrado ainda que polimorfismos funcionais no gene da MMP-9 têm sido relacionados à presença e severidade de doenças cardiovasculares. Contudo, ainda não se sabe como a associação desses polimorfismos com a obesidade infantil pode afetar as concentrações de MMP-9 no plasma. Logo, os objetivos desse trabalho foram: 1) comparar as concentrações plasmáticas de MMP-9, TIMP-1 e razão MMP-9/TIMP-1 (atividade líquida da MMP-9) entre crianças e adolescentes obesos e controles; 2) comparar as frequências genotípicas e haplotípicas dos polimorfismos C-1562T, -90(CA)14-24 e Q279R da MMP-9 entre obesos e controles e 3) correlacionar as concentrações de MMP-9 aos genótipos e haplótipos da MMP-9. Inicialmente, determinaram-se os níveis de pro-MMP-9 e no plasma, por zimografia, e as concentrações plasmáticas de MMP-9 e TIMP-1 em obesos e controles por ELISA. Nós não encontramos diferenças nas concentrações plasmáticas de MMP-9 e razão MMP-9/TIMP-1 entre obesos e controles. No entanto, nossos resultados revelaram que em obesos houve diminuição de TIMP-1. Em seguida, extraiu-se o DNA dos voluntários e determinaram-se as frequências genotípicas dos polimorfismos C -1562T e (CA)n, por PCR seguida de eletroforese, do polimorfismo Q279R, por PCR em tempo real, e as frequências haplotípicas, pelo programas PHASE. Não houve diferenças nas frequências genotípicas e haplotípicas entre os grupos. Nós avaliamos a relevância de diferentes genótipos e haplótipos nas concentrações plasmáticas de MMP-9. Para os polimorfismos C-1562T e Q279R, nós encontramos que no grupo de obesos, portadores dos genótipos CC apresentaram menores níveis de MMP-9 quando comparados aos portadores dos genótipos CT+TT e aos controles com mesmo genótipo. No grupo de obesos, portadores do genótipo QQ apresentaram menores níveis de MMP-9 quando comparados aos portadores do genótipo RR e aos controles com mesmo genótipo. Para o polimorfismo -90(CA) 14-24 não observamos diferenças nos níveis de MMP-9 entre os grupos genotípicos. Em relação aos haplótipos, no grupo de obesos, portadores do haplótipo H2 apresentaram menores concentrações de MMP-9 e da razão MMP-9/TIMP-1 (atividade líquida de MMP-9) quando comparados aos outros haplótipos e aos controles com mesmo haplótipo. No grupo controle, não observamos influência dos genótipos e haplótipos nas concentrações plasmáticas de MMP-9. Portanto, nossos achados que sugerem que genótipos (CC e QQ) e o haplótipo H2 podem diminuir os níveis circulantes de MMP-9 em crianças e adolescentes obesos, mas não em crianças saudáveis, consequentemente, estes genótipos e haplótipo poderiam oferecer proteção contra doenças cardiovasculares somente em crianças obesas / Abstract: The childhood obesity is important risk factor for cardiovascular diseases, in particular, atherosclerose. This condition is characterized by the accumulation of lipids and fibrous elements in the large arteries in which inflammatory mechanisms and vascular remodeling are involved. In this context, matrix metalloproteinase 9 (MMP-9) - endopeptidade capable of degrading components of extracellular matrix - and its endogenous inhibitor preferential, the tissue inhibitors of MMP (TIMP-1) are important mediators of this remodeling and a critical equilibrium between MMP-9 and TIMP-1 must exist in order to maintain the integrity of cardiovascular system. Moreover, elevated levels of MMP-9 have been reported in patients with cardiovascular diseases, and genetic studies showing that functional polymorphism MMP-9 gene were related to presence and severity of cardiovascular diseases. However, it remains unclear how the association of these polymorphisms with childhood obesity can affect MMP-9 plasma concentrations. Thus, the objectives of this study were: 1) to compare plasma MMP-9, TIMP-1 and MMP-9/TIMP-1(activity) ratio between obese and control groups; 2) to compare the genotype and haplotype frequencies of MMP-9 polymorphisms (C-1562T and (CA)14-24 and Q279R) between obese and control and, 3) correlate the MMP-9 concentrations with MMP-9 genotypes and haplotypes. To achieve our first goal, we determined the plasma pro-MMP-9 levels by zymography, and plasma MMP-9 and TIMP-1 concentrations by ELISA in obese and control. We not found differences in MMP-9 plasma concentratios and MMP-9/TIMP-1 between obese and control. However, our results showed that obese had lower plasma TIMP-1 concentrations than control. Moreover, to achieve our second goal, we firstly extracted DNA from volunteers, and then we determined the genotype frequencies of C-1562T and (CA)14-24 polymorphisms by PCR followed by electrophoresis, of and Q279R polymorphism by real time PCR, and the haplotype frequencies by the programs PHASE. We found similar genotype and allelic distribution for the three polymorphisms when study groups were compared. We evaluated the relevance of different genotypes in plasma MMP-9 concentrations in study groups. To the C-1562T and Q279R polymorphisms, we found that in the obese group, CC genotype carries had lower MMP-9 levels when compared with CT+TT genotype carries and control with the same genotype. In the obese group, QQ genotype carries had lower MMP-9 levels when compared with RR genotype carries and control the same genotype. To the -90(CA)14-24 polymorphism, we did not observe differences in the MMP-9 levels among different genotypic groups. In relation to haplotypes, we found that in the obese group, H2 haplotype carriers had lower MMP-9 levels and MMP-9/TIMP-1 ratio when compared other haplotypes and control with the same haplotype. Therefore, our findings suggest that (CC and QQ) genotypes and H2 haplotype decrease circulating MMP-9 levels in obese but not in healthy children, thus genotypes and haplotype could offer protection against cardiovascular diseases in those children / Mestrado / Farmacologia / Doutor em Farmacologia
105

Avaliação de polimorfismos dos genes das metaloproteinases da matriz no câncer de próstata / Evaluation of polymorphisms of matrix metalloproteinases genes in prostate cancer

Sabrina Thalita dos Reis 12 September 2008 (has links)
Introdução: O Câncer de próstata (CaP) é o mais comum do homem brasileiro. É importante a identificação de alterações moleculares que possam prever o seu desenvolvimento e potencial biológico. Polimorfismos de nucleotídeo único (SNP) são alterações da seqüência do DNA onde somente uma base é trocada com uma freqüência superior a 1% na população, que podem levar a modificações estruturais e funcionais na proteína, ou afetar a sua quantidade, e podem constituir marcadores de predisposição e prognóstico de neoplasias. Metaloproteinases (MMP) são proteínas da família de enzimas proteolíticas, que degradam a matriz extracelular, e SNP na sua estrutura têm sido associados ao comportamento de tumores. Objetivos: Avaliar a freqüencia de SNP nos genes das MMP1, 2, 7 e 9, em pacientes com CaP e grupo controle, relacionando com suscetibilidade para o desenvolvimento da doença e previsão de seu potencial biológico. Material e Métodos: A amostra é constituída por tecido não tumoral de 100 indivíduos com CaP, e 100 amostras controle representadas por soro de indivíduos saudáveis, sem câncer de próstata. O DNA foi obtido utilizando protocolos convencionais de extração. Para genotipagem foi utilizada técnica de identificação de base única com uso de sondas marcadas com fluoróforos (Taqman®) pela técnica de reação em cadeia da polimerase em tempo real. As freqüências alélicas foram calculadas e a comparação entre os grupos foi feita utilizando-se o teste de qui-quadrado com valor de significância de 0,05. Resultados: Nos genes das MMP1 a freqüência do genótipo homozigoto polimórfico esteve mais presente no grupo controle que no CaP (p>0,001). No gene da MMP9 o alelo polimórfico esteve mais presente em pacientes com CaP (p>0,001), e em tumores com escore de Gleason6 (p=0,003). No gene da MMP2 de acordo com estadiamento patológico o alelo polimórfico foi mais freqüente em tumores pT3 (p=0,026) e Gleason maior ou igual a 7(p=0,042). Conclusão: Nossos resultados sugerem que o polimorfismo no gene da MMP1 está associado a um caráter de proteção aos indivíduos quanto ao desenvolvimento do CaP. O polimorfismo no gene da MMP9 está associado a um aumento no risco de desenvolvimento desta neoplasia, e quando analisamos as associações com os fatores prognósticos encontramos uma correlação com tumores de melhor prognóstico. Por outro lado o polimorfismo do gene da MMP2 se associa a tumores não órgãoconfinados / Introduction: Prostate cancer (PCa) is the most frequent tumor in males in Brazil. Research has been directed for the identification of molecular markers that can predict the PCa predisposition and prognosis. Single nucleotide polymorphisms (SNPs) are genome variations, present in a frequency of 1% or more. The matrix metalloproteinases (MMPs) are a family of enzymes responsible for the degradation of extracellular matrix. SNPs have been demonstrated in the promoter region of these genes and have been associated with development and progression of some cancers. Objective: To investigate the correlation between polymorphisms of MMP1, 2, 7, 9 with susceptibility and classical prognostic parameters in PCa. Patients and methods: The sample is constituted by normal tissue of 100 patients with PCa, and 100 healthy men as controls (serum). DNA genomic was extracted from paraffin blocks and serum using conventional protocols. The DNA sequence containing the polymorphic sites was amplified by Real-Time polymerase chain reaction, using fluorescent probes (Taqman®). The allelic frequency was calculated and the comparison between the groups was made using the qui-square test with value of significance of 0.05. Results: The polymorphic homozygote genotype of the MMP1 was more frequent in the control group than in the PCa (p<0.001). The polymorphic allele of MMP9 was more frequent in the PCa group (p<0.001), and in tumors Gleason6 (p=0,003). The polymorphic allele of MMP2 was more frequent in tumors of higher stage (pT3) (p=0.026) and higher Gleason Score (7) (p=0.042). Conclusion: We have shown that MMP1 polymorphism is more frequent in the control group, than in patients with PCa, it may be associated to protection for the development of PCa. The MMP9 polymorphism was related to higher risk for development of this neoplasia, but associated with lower Gleason score. MMP2 polymorphism was associated with non organconfined disease.
106

Matrix metalloproteinases (MMPs) in the dentin-pulp complex of healthy and carious teeth

Sulkala, M. (Merja) 30 November 2004 (has links)
Abstract The dentin-pulp complex comprises mineralized dentin and the vital soft tissues encased inside dentin, i.e. odontoblasts and pulp tissue. During caries progression, the dentinal minerals are dissolved and eventually the collagenous organic matrix is degraded. However, the exact mechanisms and enzymes responsible for the organic matrix breakdown remain unknown. Matrix metalloproteinases (MMPs), a family of endopeptidases capable of degrading in concert virtually all extracellular matrix components, are expressed during normal dentin-pulp complex formation and maintenance. MMP activity has also been suggested to contribute to the organic matrix degradation during dentin caries progression and to the repair and defense reactions elicited by caries in the dentin-pulp complex cells. The aim of the study was to further elucidate the role of host MMPs in dentin caries progression and the origin of MMPs in carious dentin as well as the possible changes in MMP expression in the cells of the dentin-pulp complex in response to caries. MMP inhibitors decreased the area of dentin caries lesions in vivo, suggesting the involvement of host MMPs in dentin caries pathogenesis. When the overall MMP gene expression was examined by cDNA microarray, pooled pulp samples demonstrated a high level of MMP-13 expression, but failed to show any unequivocal changes in MMP expression due to caries. MMP-13 expression is rare among normal human adult tissues. Real-time quantitative PCR of individual pulp and odontoblast samples demonstrated a rather large variation in relative MMP-13 mRNA expression between samples, especially pulp samples. Protein expression of MMP-13 was detected in pulp and odontoblasts without any major differences between the tissues of sound and carious teeth. This was also the case with the MMP-20 (enamelysin) protein, which was demonstrated in odontoblasts and the pulp tissue of fully developed human teeth. MMP-20, MMP-8, and gelatinases (especially MMP-2) were demonstrated in human dentin, and dentinal MMPs exhibited activity against native and denatured type I collagen when released. The study demonstrates the presence of MMPs in the soft and hard tissue compartments of the dentin-pulp complex. These enzymes may also contribute to dentin caries progression and response reactions to caries.
107

Enzymatic cleavage of HMGB1

Rensing, Merlin January 2017 (has links)
Alarmins and damage associated molecular pattern (DAMP) are endogenous proteins with distinct and various intracellular roles that when released extracellularly act as startingsignals for inflammatory immune responses. The endogenous protein High mobility group box 1 (HMGB1) acts as a DAMP and has been shown to drive progression of multiple inflammatory and autoimmune diseases. During homeostasis HMGB1 is localized in the nucleus of almost any cell, where its main function is organization of the DNA and regulation of transcription. Upon cell death or immune cell activation HMGB1 can be translocated into the cytoplasm for subsequent release into the extracellular space. Extracellular HMGB1 can act as a DAMP by activating several receptors of the immune system. Recent studies focus on HMGB1 release and functional regulation due to prost-translational modifications (PTMs) on cysteine residues. However, little is known about enzymatic regulation of HMGB1. The aim of this thesis was to investigate the possibility of proteolytic processing of HMGB1 by enzymes, which play a crucial role in inflammatory diseases and their progression. We utilized an in vitro model that mimics natural conditions of the autoimmune disease arthritis. Enzymatic digestion of HMGB1 was performed in kinetics studies using the neutrophilic enzymes cathepsin G, neutrophil Elastase as well as matrix metalloproteinase-3, which is released from tissues at the site of inflammation. We defined that HMGB1 is a novel substrate of all of the tested enzymes. All enzymes induced different cleavage pattern. In conclusion, my findings open up the possibility for future studies involving the observed fragments of HMGB1 and their functional features. It also demonstrated that HMGB1 is affected by protease modifications in a disease relevant environment.
108

Biofonctionnalisation du silicium poreux pour la détection de MMP-8 (Collagénase-2) / Functionalization of porous silicon for MMP-8 (Collagénase-2) biosensing

Massif, Laurent 12 January 2012 (has links)
La métalloprotéinase matricielle (MMP)-8 ou collagénase-2 est capable de rompre les molécules natives, triples hélices, du collagène interstitiel, initiant ainsi le remodelage cellulaire lors du déplacement dentaire induit par une force orthodontique. C'est un bio-marqueur incontournable du remaniement tissulaire parodontal. L'augmentation de l'expression et de l'activation de MMP-8 dans le fluide gingival reflète l'activité du remodelage parodontal induit par les forces orthodontiques. En moyenne, la concentration de MMP-8 prélevée dans le fluide gingival des patients orthodontiques est 12 fois plus élevée (56 ± 50 µg/l contre 4,6 ± 4 µg/l) que chez les patients non orthodontiques. Le suivi des fluctuations de MMP-8 durant le déplacement orthodontique nécessite la mise au point d'un biocapteur. L'objectif de ce travail est d'utiliser une structure photonique à base de silicium poreux pour la conception d'un biocapteur optique de la MMP-8. Nous avons déterminé le choix du substrat de silicium poreux (PSi) le plus adapté à notre application avec une surface spécifique élevée et pores suffisamment ouverts pour l'infiltration des biomolécules qui sont des anticorps anti-MMP-8. Ensuite nous avons mis en place un procédé de fonctionnalisation chimique et biologique de la surface interne de ces échantillons. / The matrix métalloprotéinase (MMP) 8 or collagenase 2 is able to cleave native molecules, triple helixes, of the interstitial collagen, so introducing the cellular reshaping during orthodontic tooth movement. It is a major biomarker of the periodontal tissular remodeling. The increase of the expression and the activation of MMP-8 in the gingival fluid reflects the activity of the periodontal remodeling. On average, the concentration of MMP-8 taken in the gingival fluid of the orthodontic patients is 12 times as raised(brought up) (56 ± 50 µg / l against 4,6 ± 4 µg / l) that at the not orthodontic patients. Followed it by fluctuations in MMP-8 during the orthodontic movement require the development of a biosensor. The objective of this work is to use a photonique structure with porous silicon for the conception of an optical biosensor of the MMP-8. We determined the choice of the substratum of porous silicon (PSi) the most adapted to our application with a high specific surface and pores opened enough for the infiltration of the biomolecules which are antibodies anti-MMP-8. Then we set up a process of chemical and biological fonctionnalisation of the internal surface of these samples.
109

Targeting of the β6 Gene to Suppress Degradation of ECM via Inactivation of the MAPK Pathway in Breast Adenocarcinoma Cells

Zhang, Yuhua, Wei, Lijing, Yu, Jin, Li, Guang, Zhang, Xiuru, Wang, Anliu, He, Yanjiao, Li, Hongli, Yin, Deling 01 January 2014 (has links)
Integrin αvβ6 has emerged as a potential novel target for anticancer and plays a major role in promoting malignant tumor progression. Recent studies indicate that integrin αvβ6 occurs in many cancers. However, whether and how αvβ6 is regulated by genetic and epigenetic mechanisms in breast cancer remain unknown. In the present study, two different short hairpin RNAs (shRNAs) targeting the β6 gene were designed and constructed into pSUPER, respectively, which were transfected into the MCF-7 human breast adenocarcinoma cell line. The β6-shRNA stably transfected cells were successfully established, and significant lower levels of αvβ6 mRNA and protein expression were confirmed. Furthermore, inhibition of integrin αvβ6 markedly downregulated the expression of matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-3 (MMP-3) and urokinase plasminogen activator (uPA) in tumor conditioned medium. Furthermore, β6-shRNA-mediated silencing of the αvβ6 gene obviously decreased the expression of ERK1/2. In particular, supression of integrin αvβ6 caused significant downregulation of the degradation of basement membrane type IV collagen secretion via modulation of the plasminogen activation cascade. Our results thus indicate that αvβ6 plays a fundamental role in promoting invasion and growth of breast adenocarcinoma cells. Taken together, this study revealed that targeting of the β6 gene by RNA interference (RNAi) could efficiently downregulate αvβ6 expression and suppress the ERK1/2-dependent extracellular matrix degradation in vitro, which is dependent upon inactivation of the mitogen-Activated protein kinase (MAPK) pathway. These findings may offer a useful therapeutic approach to block invasion and migration of breast cancer cells.
110

Cannabinoid Receptor Type 2 (CB2) Deficiency Alters Atherosclerotic Lesion Formation in Hyperlipidemic Ldlr-Null Mice

Netherland, Courtney D., Pickle, Theresa G., Bales, Alicia, Thewke, Douglas P. 01 November 2010 (has links)
Objective: To determine if cannabinoid receptor 2 (CB2) plays a role in atherosclerosis, we investigated the effects of systemic CB2 gene deletion on hyperlipidemia-induced atherogenesis in low density lipoprotein receptor-deficient (Ldlr-/-) mice. Methods and results: Ldlr-/- and CB2/Ldlr double knockout (CB2-/-Ldlr-/-) mice were fed an atherogenic diet for 8 and 12 weeks. Morphometric analysis revealed no significant difference between the atherosclerotic lesion area in the proximal aortas of Ldlr-/- and CB2-/-Ldlr-/- mice after 8 or 12 weeks on the atherogenic diet. The macrophage and smooth muscle cell (SMC) content, as revealed by immunohistochemical staining, did not differ significantly between Ldlr-/- and CB2-/-Ldlr-/- lesions after 8 weeks. However, after 12 weeks, CB2-/-Ldlr-/- lesions displayed greater macrophage content (86.6±4.1 versus 75.2±7.5%, P<0.05) and SMC content (11.1±5.1 versus 4.2±2.4%, P<0.05) compared to controls. Lesional apoptosis, as determined by in situ TUNEL analysis, was reduced ∼50% in CB2-/-Ldlr-/- lesions after 12 weeks. CB2-/-Ldlr-/- lesions displayed significantly reduced collagen content and increased elastin fiber fragmentation after 12 weeks, which was associated with an ∼57% increase in matrix metalloproteinase 9 (MMP) levels. In vitro, CB2-/- macrophages secreted ∼1.8-fold more MMP9 activity than CB2+/+ macrophages. Conclusions: CB2 receptor deficiency affects atherogenesis in Ldlr-null mice by increasing lesional macrophage and SMC content, reducing lesional apoptosis and altering extracellular matrix components, in part, by upregulating MMP9. These results suggest that pharmacological manipulation of CB2 receptors might exert multiple and complex effects on atherogenesis and plaque stability.

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