Lors de la fibrose pulmonaire idiopathique (FPI), la différenciation fibroblastique s’accompagne d’une accumulation excessive des composants de la matrice extracellulaire ainsi qu’à un dérèglement de la balance protéases / antiprotéases. Nous avons étudié le rôle des cathepsines à cystéine dans la myofibrogenèse et leur contribution potentielle à la physiopathologie de la fibrose pulmonaire chez l’Homme. Pour cela, le profil d’expression des cathepsines ainsi que de leurs inhibiteurs naturels a été évalué dans un modèle cellulaire expérimental, puis dans des myofibroblastes primaires et enfin dans des liquides de lavage broncho-Alvéolaires (LBA) de patients atteints de FPI. Nos résultats montrent que lors de la FPI la cystatine C (inhibiteur naturel des protéases à cystéine) régule les activités protéolytiques des cathepsines extracellulaires et pourrait ainsi contribuer à l’accumulation de collagènes. Elle serait un biomarqueur potentiel de la FPI. D’autre part la cathepsine B participe à la différentiation fibroblastique et son inhibition retarde la myofibrogenèse. / During idiopathic pulmonary fibrosis (IPF), fibroblast differentiation is accompanied by an excessive accumulation of extracellular matrix components as well as an imbalance between proteases and theirs inhibitors. We evaluated the role of human cysteine cathepsins in myofibrogenesis and their potential contribution to the pathogenesis of IPF. Expression of cathepsins and their natural inhibitors have been studied in an experimental cell model, but also in primary myofibroblasts and in bronchoalveolar lavage fluids (BALF) of patients suffering from IPF. Our results show that cystatin C (a natural inhibitor of cysteine proteases) regulates the extracellular proteolytic activities of cathepsins and could contribute to the accumulation of collagens. Cystatin C could also be a potential biomarker of IPF. On the other hand, cathepsin B participates in fibroblast differentiation and its inhibition delays myofibrogenesis.

Submitted by Raniere Barreto (raniere.barros@ufvjm.edu.br) on 2018-04-12T16:59:34Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lara_franca_colares.pdf: 2530593 bytes, checksum: f6b37bbb6a95d44536fc10c983a32afa (MD5) / Rejected by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br), reason: Verificar: "Ara?jo e Silva" e alterar, deixando Silva. Inserir as keywords adicionado campos devidos. UFVJM n?o ? ag?ncia financiadora. on 2018-04-20T14:32:10Z (GMT) / Submitted by Raniere Barreto (raniere.barros@ufvjm.edu.br) on 2018-05-15T17:49:49Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lara_franca_colares.pdf: 2530593 bytes, checksum: f6b37bbb6a95d44536fc10c983a32afa (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-05-16T11:27:14Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lara_franca_colares.pdf: 2530593 bytes, checksum: f6b37bbb6a95d44536fc10c983a32afa (MD5) / Made available in DSpace on 2018-05-16T11:27:14Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lara_franca_colares.pdf: 2530593 bytes, checksum: f6b37bbb6a95d44536fc10c983a32afa (MD5) Previous issue date: 2016 / Plantas medicinais s?o comumente usadas por comunidades tradicionais, principalmente em regi?es com menor desenvolvimento humano. Algumas esp?cies vegetais possuem entre seus componentes subst?ncias denominadas inibidores de proteases. Os inibidores de proteases se destacam na prote??o de fluidos e tecidos contra sua degrada??o por prote?lise e poss?veis falhas na degrada??o de prote?nas de meia-vida que podem interferir de forma dr?stica nas fun??es celulares. Diante do exposto, esse estudo objetivou identificar e caracterizar inibidores de proteases em cinco esp?cies vegetais nativas do Cerrado e da Mata Atl?ntica. As esp?cies de Punica granatum L. (Rom?), Plantago major L. (Tansagem), Ocimum gratissimum L. (Alfavaca), Anadenanthera colubrina Vellozo (Angico) e Stryphnodendron adstringens Mart. Coville (Barbatim?o) foram selecionados nas cidades de Pot?, Ladainha, Atal?ia, Te?filo Otoni e Ara?ua?, devido ao seu uso tradicional como anti-inflamat?rio. A sequencia gen?mica de inibidores de proteases foi pesquisada para essas esp?cies vegetais no GenBank, mas nenhuma sequencia foi descrita para as esp?cies selecionadas. As amostras provenientes dos procedimentos de extra??o foram submetidas ?s quantifica??o de prote?nas e a presen?a de inibidores de proteases foi detectada por eletroforese em gel de poliacrilamida 12% SDS-PAGE. Somente os extratos das sementes de Punica granatum e das folhas do Anadenanthera colubrina tiveram detec??o satisfat?ria de inibidores de proteases e foram submetidos ? an?lise por cromatografia l?quida de alta efici?ncia em sistema de HPLC. Este trabalho demonstra pela primeira vez a detec??o e extra??o de inibidores de proteases em folhas de Anadenanthera colubrina e sementes de Punica granatum. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Tecnologia, Sa?de e Sociedade, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / Traditional communities, especially in regions with lower human development, commonly use medicinal plants. Some plant species have among their components substances called protease inhibitors. Protease inhibitors act protecting fluids and tissues from degradation by proteolysis and possible failures in the degradation of half-life proteins that can drastically interfere with cellular functions. This study aimed to identify and characterize protease inhibitors in five native plant species of Cerrado and Atlantic Forest. The species of Punica granatum L. (Rom?), Plantago major L. (Tansagem), Ocimum gratissimum L. (Alfavaca), Anadenanthera colubrina Vellozo (Angico) and Stryphnodendron adstringens Mart. Coville (Barbatim?o) were selected in the cities of Pot?, Ladainha, Atal?ia, Te?filo Otoni and Ara?ua? due to their traditional use. The genomic sequence of protease inhibitors was screened for these plant species in GenBank, but no sequence was described for the selected species. Samples from the extraction procedures were subjected to protein quantification and the presence of protease inhibitors was detected by 12% SDS-PAGE polyacrylamide gel electrophoresis. Only the extracts of the seeds of Punica granatum and of the leaves of Anadenanthera colubrina had satisfactory detection of proteases inhibitors and were submitted to the analysis by high performance liquid chromatography system. This work demonstrates for the first time the detection and extraction of protease inhibitors in leaves of Anadenanthera colubrina and seeds of Punica granatum.

RÊGO, João Paulo Arcelino do. Análise proteômica do plasma seminal de carneiros Santa Inês adulto. 2010. 107 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Zootecnia, Fortaleza-CE, 2010 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-29T14:08:18Z No. of bitstreams: 1 2010_dis_jparego.pdf: 805870 bytes, checksum: a59ce42229b6d0d23c4b460911c6fe88 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-29T14:08:32Z (GMT) No. of bitstreams: 1 2010_dis_jparego.pdf: 805870 bytes, checksum: a59ce42229b6d0d23c4b460911c6fe88 (MD5) / Made available in DSpace on 2016-07-29T14:08:32Z (GMT). No. of bitstreams: 1 2010_dis_jparego.pdf: 805870 bytes, checksum: a59ce42229b6d0d23c4b460911c6fe88 (MD5) Previous issue date: 2010 / Northeastern Brazil has a significant population of sheep and, among the native hairy breeds, Santa Inês is known for its good performance and adaptability to tropical environments. Recently, it has been shown that the protein profile of the seminal plasma of Santa Inês rams changes during sexual development, in concert with changes in semen parameters, such as sperm motility, morphology and concentration. However, the identity of seminal plasma proteins from these hairy rams is still unknown. Therefore, we pursued the identification of seminal plasma proteins from Santa Inês rams using a proteomic approach. Semen samples were collected from eight mature rams, and seminal plasma saved after centrifugation. Seminal plasma protein maps, obtained by two-dimensional electrophoresis, were stained with colloidal Coomassie. The gels were scanned and analyzed using PDQuest software. Protein spots were individually cut, in-gel digested with trypsin and identified after tandem mass spectrometry and database search. On average , we detected 302 spots per gel, from which 143 were present on every member of the match set generated by PDQuest. Thirty-nine spots were positively identified by mass spectrometry, corresponding to 26 different proteins. The major proteins present in the maps were the BSP-like RSVP14 and RSVP22 and the spermadhesins bodhesin 1 and 2. Other proteins detected in the maps included albumin, clusterin, peroxiredoxin, lactoferrin, transferrin, matrix metalloproteinase 2, beta galactosidase and heat shock proteins. The Identity of these proteins suggest their participation on several physiological events, such as sperm protection, regulation of sperm motility and capacitation, modification of sperm membrane and fertilization. The knowledge of the proteome of the ovine seminal plasma is a necessary step towards the understanding of the mechanisms underlying the regulation of sperm function by seminal plasma components in rams / O Nordeste brasileiro é detentor de um expressivo rebanho ovino, e, dentre as raças deslanadas existentes na região, a Santa Inês se destaca por apresentar bom desenvolvimento corporal, ganho de peso e adaptabilidade às condições tropicais. Recentemente, demonstrou-se que o perfil protéico do plasma seminal de carneiros Santa Inês passa por alterações significativas durante o desenvolvimento reprodutivo, simultaneamente a mudanças nos parâmetros de motilidade e concentração espermática. Contudo, ainda não se conhece a identidade de todas essas proteínas. Dessa forma, o presente trabalho foi conduzido com o objetivo de identificar as proteínas do plasma seminal de carneiros Santa Inês maduros, utilizando as técnicas de eletroforese bidimensional associada à espectrometria de massa. Amostras de sêmen foram coletadas de oito carneiros adultos e o plasma seminal obtido através de centrifugação e submetido à eletroforese bidimensional. Os géis foram corados com Coomassie coloidal, digitalizados e analisados no aplicativo PDQuest. Os spots foram cortados individualmente dos géis, digeridos com tripsina, e submetidos a identificação por espectrometria de massa (MALDI-ToF/ToF). A sequência peptídica das proteínas mais abundantes e a distribuição dos domínios foram representadas graficamente utilizando o aplicativo Caititu. Foram detectados, em média, 302 spots por gel. Destes, 143 estavam presentes em todos os géis. Trinta e nove spots foram identificados, correspondendo a 26 diferentes proteínas. As proteínas mais abundantes foram as RSVPs 14 e 22 kDa, pertencentes à família das binder of sperm proteins, e as Bodesinas-1 e 2, pertencentes à família das espermadesinas. Outras proteínas foram identificas no estudo, incluindo albumina, clusterina, peroxiredoxina, lactotransferrina, metaloproteinase de matriz 2 (MMP-2), beta galactosidase e heat shock proteins. Dessa forma, a identidade dessas proteínas sugere que o plasma seminal de carneiros Santa Inês contém componentes que participam de diversos processos fisiológicos, incluindo proteção do espermatozóide, modulação da motilidade e capacitação espermática, modificação da membrana do espermatozóide e interação entre gametas. O conhecimento dessas proteínas contribuirá para uma melhor compreensão dos mecanismos de regulação do plasma seminal sobre a função espermática em ovinos

Made available in DSpace on 2015-07-22T20:50:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-29 / O Aedes aegypti é o vetor mais importante de arboviroses humana sendo responsável pelas transmissões de dengue e febre amarela urbana. As enzimas tipo tripsina apresentam um importante papel na digestão de estádios de vida larval e adulto de Ae. aegypti. No presente trabalho, nós identificamos as duas enzimas tipo tripsina majoritárias do intestino médio larval através da construção de uma biblioteca de fragmentos de cDNA de tripsina. Elas são AAEL005607 e AAEL006371, com frequências de expressão de 29,3% e 20%, respectivamente. Análises por PCR semi-quantitativo mostraram que a tripsina AAEL005607 foi transcrita em todos os instars larval, mas a tripsina AAEL006371 apareceu somente nos 3º e 4º instar larvais. A fim de confirmar os dados de transcrição, enzimas tipo tripsina do intestino médio de larvas de 4º instar foram purificadas por cromatografias de afinidade, troca iônica e fase reversa. A tripsina purificada apresentou massa molecular de 28 kDa por SDS-PAGE. Sua sequência de aminoácidos parcial nos permitiu sugerir que a atividade de tripsina é codificada pela sequência AAEL005607. A tripsina purificada (AAEL005607) exibiu um valor de Km de 36,4 μM para o substrato Tosyl-Gly-Pro-Arg-pNa e foi fortemente inibida por AaTI e HiTI, ambos inibidores de tripsina, com valores de Ki de 0,94 pM e 160 pM, respectivamente. Em conclusão, pela primeira vez, a enzima digestiva majoritária de 4º instar larval de Ae. aegypti foi purificada e caracterizada. / Aedes aegypti is the most important vector of human arboviral diseases and it is responsible for dengue and urban yellow fever transmissions. Trypsin-like enzymes plays an important role in the Ae. aegypti adult and larval life stages digestion. In the present work, we identified the two major trypsin-like enzymes of Ae. aegypti larval midgut through the trypsin cDNA fragments library construction. They are AAEL005607 and AAEL006371, with expression frequencies of 29.3% and 20%, respectively. Semi quantitative PCR analysis showed that the AAEL005607 was transcripted in all larval instars, but AAEL006371 appeared only in 3rd and 4th larval instars. In order to confirm the transcription data, trypsin-like enzymes from 4th instar larvae of Ae. aegypti midgut were purified by affinity, ionic exchange and reversedphase chromatographies. Purified trypsin presented molecular mass of 28 kDa by SDS-PAGE. Its partial amino acid sequence allowed us to suggest that the trypsin activity is encoding by AAEL005607 sequence. The purified trypsin (AAEL005607) showed Km value of 36.4 μM for Tosyl-Gly-Pro-Arg-pNa substrate and was strongly inhibited by AaTI and HiTI, both trypsin inhibitors, with Ki of 0.94 pM and 160 pM, respectively. In conclusion, for the first time, the major digestive enzyme of 4th larval instar of Ae. aegypti was identified and characterized. / TEDE / BV UNIFESP: Teses e dissertações

Made available in DSpace on 2016-02-26T13:36:33Z (GMT). No. of bitstreams: 2 amanda_hammes_ioc_mest_2012.pdf: 2580577 bytes, checksum: c40f0f68c566ee77505a8966c14e2e8e (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2016-01-13 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / Uma família de enzimas do tipo aspartil proteases, conhecida como Plasmepsinas, tem sido descrita como alvo atrativo para pesquisa e desenvolvimento de novos compostos terapêuticos para o tratamento da malária. Isto se deve ao fato de que no vacúolo alimentar do parasita existem quatro Plasmepsinas ativas e a inibição destas impede que o parasita degrade a hemoglobina, sua fonte de nutrientes para crescimento e maturação. Sabendo-se que os parasitas Plasmodium falciparum spp. adquirem uma rápida resistência aos atuais fármacos antimalariais, se faz necessário que novos e mais efetivos fármacos sejam descobertos para tratamento desta doença. A área de planejamento de novos fármacos baseado em estrutura (Structure Based Drug Design - SBDD) é considerada estratégica pois se baseia em uma maior compreensão dos mecanismos de reconhecimento molecular através da utilização de métodos computacionais O objetivo deste trabalho foi estudar, através da identificação dos modos de ligação e da determinação da energia livre de ligação, uma nova série de compostos planejados pelo Departamento de Síntese Orgânica de Farmanguinhos-Fiocruz. Métodos de docking e dinâmica molecular foram combinados e mostraram vantagens na utilização conjunta dessas técnicas apresentando uma boa correspondência entre o valor de energia livre de ligação, calculado através do método LIE, e o valor da afinidade de ligação obtida experimentalmente para os compostos estudados. Os resultados foram satisfatórios pois mostraram que os métodos usados no estudo de interações receptor-ligante envolvendo moléculas da família de aspartil proteases são interessantes na determinação dos plausíveis modos de ligação dos protótipos no sítio de ligação do alvo molecular / A family of aspartyl proteases enzyme, known as Plasmepsins, has been described as attractive target for research and development of new therapeutic com pounds for treatment of malaria. This is because within the digestive vacuole of the parasite there exist four active Plasmepsins whose inhibition prevents these parasites to degrade the hemoglobin which is the source of nutrients for their growth and matu ration. Bearing in mind that the parasites of the genre Plasmodium falciparum spp . acquire a rapid resistance to the antimalarial drugs currently on the market, it is necessary that new and more effective compounds are discovered to treat the disease. The field of Structure Based Drug Design – SBDD is nowadays considered crucial because it relies on the profound understanding of the mechanisms of molecular recognition through the use of computational methods. Thus, the goal of this study was to identify th e binding modes and determining the free energy of binding of a new series of compounds planned by the Department of Organic Synthesis of Farmanguinhos – FIOCRUZ. The joint application of docking and molecular dynamics methodologies showed advantages in us ing these techniques together. The results presented a good correspondence between the calculated free energy values using the Linear Interaction Energy – LIE method of compounds and their experimental values. The results may be considered satisfactory in the context of this job and show that the approach here applied to study receptor - ligand interactions involving molecules of the aspartyl proteases family was adequate in determining the plausible binding modes of prototypes molecules in the target binding site

MONTEIRO JUNIOR, José Edvar. Detecção de inibidores de proteinases cisteínicas em raízes de feijão-de-corda [Vigna unguiculata (L.) Walp.] e avaliação de sua atividade sobre o nematóide das galhas Meloidogyne javanica. 2007. xx, 107 f. : Dissertação (Mestrado em Bioquímica) - Universidade Federal do Ceará, Fortaleza-CE, 2007. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-05-30T13:05:54Z No. of bitstreams: 1 2007_dis_jemonteirojunior.pdf: 3368722 bytes, checksum: 6db6741733e59f2f818b4ae00227e385 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-11T23:30:16Z (GMT) No. of bitstreams: 1 2007_dis_jemonteirojunior.pdf: 3368722 bytes, checksum: 6db6741733e59f2f818b4ae00227e385 (MD5) / Made available in DSpace on 2016-07-11T23:30:16Z (GMT). No. of bitstreams: 1 2007_dis_jemonteirojunior.pdf: 3368722 bytes, checksum: 6db6741733e59f2f818b4ae00227e385 (MD5) Previous issue date: 2007 / Detection of cysteine proteinase inhibitors in cowpea[Vigna unguiculata(L.) Walpers] roots as well as the accumulation of inhibitors enriched fractions throughammonium sulfate precipitation followed by reversed-phase liquid chromatography were in this present work accomplished. Fractions containing higher levels of cysteine proteinase inhibitor activity were selected and subjected to evaluation of its ability of to suppress the mobility of second stage juveniles (J2) of the root-knot nematode Meloidogyne javanica, race 1. In addition, the nematicidal effect of these fractions was also tested. When the mobility parameter was analyzed the ammonium sulfate precipitated F 30/60 fraction, at a dose of 40 μg of proteins, it shown to be the most potent of all tested samples at 24 h after incubation. However, regarding to mortality the both picks, PIHPLC and PIIHPLC, obtained from the HPLC step were the more actives causing a percentage of killing nematodes of 95.0 % and 94.2 %, respectively when the most potent doses of these picks were compared. Moreover, FITC-coupled F 30/60 fraction was used in light-flu orescence microscopy experiments in order to answer the following basic questions: 1) the observed effects on mobility and mortality will be related to the binding of the proteins in the nematode? And 2) If yes, this interaction is performed with the gut or surface nematode, or yet in the both structures? F 30/60 fraction appears to be incorporated by juveniles and specifically bind to the region corresponding to the gut of nematodes at 6 h after incubation, while at 24 h after incubation the fluorescent complex appears to be widespread along the whole body of the nematode, as observed by light-fluorescence microscopy. These results, all together, suggest the possible use of the inhibitors present in cowpea roots as a potential biological tool in the control of the root-knot nematode, M. javanica. / A detecção de inibidores de proteinases cisteínicas em raízes de feijão-de-corda [Vigna unguiculata (L.) Walpers] bem como o acúmulo de frações ricas nestes inibidores por meio de precipitação com sulfato de amônio seguida de cromatografia líquida de fase reversa foram realizados no presente trabalho. Frações contendo os maiores níveis de atividade de inibidores de proteinases cisteínicas foram selecionadas e sujeitas à avaliação de sua habilidade em suprimir a mobilidade de juvenis de segundo estágio (J2) do nematóide das galhas Meloidogyne javanica, raça 1. Em adição o efeito nematicida destas também foi avaliado. Quanto ao parâmetro mobilidade, a fração F 30/60 precipitada com sulfato de amônio, numa dose de 40 µg de proteínas, mostrou ser a mais potente de todas as amostras testadas, às 24 h de incubação. No entanto, com relação à mortalidade ambos os picos PIHPLC e PIIHPLC, obtidos dos passos de HPLC, foram os mais ativos causando um percentual de mortes de nematóides de 95,0 e 94,7 %, respectivamente, quando as doses mais potentes destes picos foram comparadas. Além disso, a fração F 30/60 acoplada a FITC foi usada em experimentos de microscopia de luz-fluorescência para responder as seguintes questões: 1) Estariam os efeitos observados sobre a mobilidade e mortalidade relacionados à ligação das proteínas no nematóide? e 2) Se sim, esta interação é realizada com a superfície do nematóide ou seu intestino, ou com ambas estruturas? A fração F 30/60 parece ser incorporada pelos juvenis e ligar-se especificamente à região correspondente ao intestino dos nematóides às 6 h após incubação, enquanto que às 24 h após incubação o complexo fluorescente parece se dispersar ao longo de todo o corpo do nematóide, como observado pela microscopia de luz-fluorescência. Estes resultados, somados, sugerem o possível uso dos inibidores presentes em raízes de feijão-de-corda como ferramentas biológicas potenciais no controle do nematóide das galhas, M. javanica.

A lagarta da espécie Lonomia obliqua é medicamente importante, cujo veneno, presente nas espículas, causa uma síndrome hemorrágica caracterizada por equimoses, alterações da coagulação, dentre outros sintomas. Isto sugere a presença de peptídeos bioativos com potencial farmacêutico, devido à capacidade de modular o comportamento das células endoteliais. O objetivo deste estudo é analisar os potenciais efeitos do veneno de Lonomia obliqua na angiogênese. Uma linhagem celular endotelial (HUVEC) foi exposta a diferentes concentrações do extrato de espículas da Lonomia obliqua (Lonomia obliqua Bristle extract - LOBE) 5 μg/mL, 10 μg/mL, 20 μg/mL e 50 μg/mL. Empregando citometria de fluxo, observou-se que nenhuma das doses afetou o ciclo celular, viabilidade ou apoptose das células endoteliais após 24h de exposição. Os esferóides das células HUVEC foram plaqueados numa matriz 3D de colágeno e observou-se que LOBE (10 μg/mL, 20 μg/mL e 50 μg/mL) induz um aumento na migração celular, consistente com o processo de angiogênese. A análise da dinâmica da VE-caderina indica que a exposição imediata a LOBE (10 μg/mL) induz um desprendimento da junção célula-célula, o que corrobora com a hemorragia observada nas vítimas de envenenamento. Através de espectrometria de massa, observou-se que LOBE possui vários potenciais peptídeos bioativos. Grupos destes peptídeos foram isolados por fracionamento com metanol a partir do veneno bruto. Os peptídeos presentes, em cada uma das 10 frações, foram caracterizados por espectrometria de massa e foram analisados os efeitos de cada fração sobre a angiogênese. Os resultados sugerem que alguns dos efeitos do envenenamento por Lonomia obliqua são devidos à presença de peptídeos bioativos que modulam o comportamento das células endoteliais. / The caterpillar of the species Lonomia obliqua is medically important, whose venom present in the bristles leads to an hemorrhagic syndrome characterized by ecchymosis, coagulation disorders and others symptoms. This suggests the presence of bioactive peptides with pharmaceutical potencial due to the ability to modulate the behavior of endothelial cells. The aim of this study is to analyze the potential effects of Lonomia obliqua venom on angiogenesis. An endothelial cell line (HUVEC) was exposed to different concentrations (5 μg/mL, 10 μg/mL, 20 μg/mL and 50 μg/mL) of Lonomia obliqua bristle extract (LOBE). Using flow cytometry, it was observed that none of the doses affected endothelial cell cycle, cell viability or apoptosis after 24h of exposition. Spheroids of HUVEC cells were plated in a 3D-collagen matrix and it was observed that LOBE (10 μg/mL, 20 μg/mL and 50 μg/mL) induced an increase on cell migration consistent with the angiogenesis process. Analysis of VE-cadherin dynamics indicates that the immediate exposition to LOBE (10 μg/mL) induced a loosening of cell-cell junction, which corroborates with the hemorrhage observed in the victims. By mass spectroscopy, it was observed that LOBE possesses several potentially bioactive peptides. Groups of these peptides were isolated by a methanol-based fractioning of the crude venom. The peptides present in each of the 10 fractions were characterized by mass spectroscopy and it was analyzed the effects of each fraction on angiogenesis. The results suggest that some of the effects of Lonomia obliqua envenomation are due to the presence of bioactive peptides that modulate the behavior of endothelial cells.

A lagarta da espécie Lonomia obliqua é medicamente importante, cujo veneno, presente nas espículas, causa uma síndrome hemorrágica caracterizada por equimoses, alterações da coagulação, dentre outros sintomas. Isto sugere a presença de peptídeos bioativos com potencial farmacêutico, devido à capacidade de modular o comportamento das células endoteliais. O objetivo deste estudo é analisar os potenciais efeitos do veneno de Lonomia obliqua na angiogênese. Uma linhagem celular endotelial (HUVEC) foi exposta a diferentes concentrações do extrato de espículas da Lonomia obliqua (Lonomia obliqua Bristle extract - LOBE) 5 μg/mL, 10 μg/mL, 20 μg/mL e 50 μg/mL. Empregando citometria de fluxo, observou-se que nenhuma das doses afetou o ciclo celular, viabilidade ou apoptose das células endoteliais após 24h de exposição. Os esferóides das células HUVEC foram plaqueados numa matriz 3D de colágeno e observou-se que LOBE (10 μg/mL, 20 μg/mL e 50 μg/mL) induz um aumento na migração celular, consistente com o processo de angiogênese. A análise da dinâmica da VE-caderina indica que a exposição imediata a LOBE (10 μg/mL) induz um desprendimento da junção célula-célula, o que corrobora com a hemorragia observada nas vítimas de envenenamento. Através de espectrometria de massa, observou-se que LOBE possui vários potenciais peptídeos bioativos. Grupos destes peptídeos foram isolados por fracionamento com metanol a partir do veneno bruto. Os peptídeos presentes, em cada uma das 10 frações, foram caracterizados por espectrometria de massa e foram analisados os efeitos de cada fração sobre a angiogênese. Os resultados sugerem que alguns dos efeitos do envenenamento por Lonomia obliqua são devidos à presença de peptídeos bioativos que modulam o comportamento das células endoteliais. / The caterpillar of the species Lonomia obliqua is medically important, whose venom present in the bristles leads to an hemorrhagic syndrome characterized by ecchymosis, coagulation disorders and others symptoms. This suggests the presence of bioactive peptides with pharmaceutical potencial due to the ability to modulate the behavior of endothelial cells. The aim of this study is to analyze the potential effects of Lonomia obliqua venom on angiogenesis. An endothelial cell line (HUVEC) was exposed to different concentrations (5 μg/mL, 10 μg/mL, 20 μg/mL and 50 μg/mL) of Lonomia obliqua bristle extract (LOBE). Using flow cytometry, it was observed that none of the doses affected endothelial cell cycle, cell viability or apoptosis after 24h of exposition. Spheroids of HUVEC cells were plated in a 3D-collagen matrix and it was observed that LOBE (10 μg/mL, 20 μg/mL and 50 μg/mL) induced an increase on cell migration consistent with the angiogenesis process. Analysis of VE-cadherin dynamics indicates that the immediate exposition to LOBE (10 μg/mL) induced a loosening of cell-cell junction, which corroborates with the hemorrhage observed in the victims. By mass spectroscopy, it was observed that LOBE possesses several potentially bioactive peptides. Groups of these peptides were isolated by a methanol-based fractioning of the crude venom. The peptides present in each of the 10 fractions were characterized by mass spectroscopy and it was analyzed the effects of each fraction on angiogenesis. The results suggest that some of the effects of Lonomia obliqua envenomation are due to the presence of bioactive peptides that modulate the behavior of endothelial cells.

Orientador: Sergio Roberto Peres Line / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-10T16:39:26Z (GMT). No. of bitstreams: 1 EspiritoSanto_AlexandreRibeirodo_D.pdf: 9422040 bytes, checksum: 9034465ff462c933a4d9d5ab9721b610 (MD5) Previous issue date: 2008 / Resumo: O esmalte envolve a porção coronária dos dentes e constitui a estrutura mais mineralizada do corpo vertebrado. Seu desenvolvimento tem início com secreção, processamento proteolítico e auto-agregação de uma complexa mistura de proteínas. O estabelecimento de uma matriz orgânica ordenada parece ser fundamental para a formação adequada da fase mineral do esmalte. Microscopia de luz polarizada mostra que a matriz orgânica do esmalte secretório (MOES) apresenta-se fortemente birrefringente em cortes não corados de 5 µm de espessura. Esta propriedade reflete alto grau de organização em nível molecular com possível relevância funcional. Alterações no brilho de birrefringência da MOES podem indicar desordens moleculares e estar associadas a alterações na formação da fase mineral. Atraso no processo de fixação da MOES pode levar a uma rápida perda de sua birrefringência, comprometendo o seu estudo por meio de microscopia de luz polarizada. No presente trabalho, analisaram-se os efeitos do nocauteamento dos genes Amelx e Mmp20 (experimento 1), dos bisfosfonatos (experimento 2) e de inibidores de serina proteinases e metaloproteinases (experimento 3) sobre a birrefringência da MOES. O experimento 1 mostrou quecamundongos fêmeas Amelx+/- apresentam redução significativa no brilho debirrefringência quando comparados aos animais Amelx+/+ do mesmo gênero (p=0,0029). A MOES dos camundongos fêmeas Amelx-/- não exibiu birrefringência. Os camundongos Mmp20-/- mostraram uma expressiva diminuição nos valores de retardo ótico em comparação aos camundongos Mmp20+/+ e Mmp20+/- (p=0,0000). Os animais Mmp20+/+ e Mmp20+/- apresentaram birrefringência semelhante (p=1,0000). O experimento 2 mostrou que ratos tratados com alendronato de sódio não apresentam alterações morfológicas na MOES, mas exibem diminuiçãoexpressiva no brilho de birrefringência quando comparados a ratos controles (p<0,01). Interessantemente, os ratos tratados com etidronato dissódico apresentaram alterações morfológicas severas na MOES, mas mostraram brilho de birrefringência na matriz secretada semelhante ao dos ratos controles (p>0,05). O experimento 3 mostrou que a fenantrolina (inibidora de metaloproteinases, como a Mmp20) e o fenilmetilsulfonil fluoreto (inibidor de serina proteinases, como a Klk- 4) preservam a birrefringência da MOES ex vivo. Os resultados aqui apresentados sugerem que: 1) a birrefringência da MOES depende da organização supramolecular das amelogeninas e é influenciada pela atividade proteolítica da Mmp20; 2) o alendronato de sódio pode induzir alterações quantitativas na organização supramolecular da MOES; 3) o etidronato dissódico não altera a ordem molecular da matriz orgânica do esmalte secretada e pode induzir defeitos no esmalte maduro através de interferência direta sobre a atividade secretora dos ameloblastos; 4) a rápida perda de birrefringência da MOES em amostras não imediatamente fixadas é resultante da atividade de proteinases do esmalte. Palavras-chave: Esmalte dentário, Birrefringência, Bisfosfonatos, Fenantrolina, Fenilmetilsulfonil fluoreto / Abstract: Enamel covers dental crown and is the most mineralized structure in the vertebrate body. Its development begins with the secretion, processing and selfassembly of a complex mixture of proteins. The establishment of an ordered organic matrix seems to be a crucial step for the proper formation of enamel mineral phase. Polarizing microscopy shows that the secretory-stage enamel organic matrix (SEOM) is strongly birefringent in non-stained 5 µm-thick sections. This property indicates high level of molecular organization, which may be physiologically important. Changes in SEOM birefringence brightness may reflect molecular disorders and may be associated with alterations in the forming enamel mineral phase. Delay in fixation of SEOM may lead to rapid loss of birefringence, impairing analysis of that tissue with polarized light microscopy. In the present work, we analyzed the effects of Amelx and Mmp20 knocking out (experiment 1), bisphosphonates (experiment 2) and metallo and serine proteinases¿ inhibitors (experiment 3) on SEOM birefringence. Experiment 1 showed that Amelx+/- female mice exhibit a significant reduction in the birefringence brightness when compared to Amelx+/+ female animals. (p=0.0029). The SEOM from Amelx-/- female mice did not show birefringence. Mmp20-/- mice presented an expressive reduction in the optical retardation values in comparison to Mmp20+/+ and Mmp20+/- animals (p=0.0000). Mmp20+/+ and Mmp20+/- mice presented similar birefringence (p=1.0000). Experiment 2 showed that rats treated with sodium alendronate do not present morphological alterations in the SEOM, but exhibit significant decrease in the birefringence brightness when compared to control rats (p<0.01). Interestingly, bisodic etidronate rats showed severe morphological alterations in the SEOM, but exhibited SEOM birefringence brightness similar to that observed in control rats (p>0.05). Experiment 3 evidenced that 1,10-phenanthroline (metalloproteinase inhibitor) and phenylmethylsulphonyl fluoride (serine proteinase inhibitor) preserve SEOM birefringence brightness ex vivo. The results presented here support the following conclusions: 1) SEOM birefringence results from amelogenin supramolecular organization and is influenced by proteolytic activity of Mmp20; 2) sodium alendronate can induce quantitative changes in the supramolecular organization of the SEOM; 3) bisodic etidronate does not disturb molecular order of the secreted enamel organic matrix and may induce changes in mature enamel by affecting directly secretory activity of ameloblasts; 4) rapid loss of birefringence in no immediately fixed SEOM is caused by the activity of enamel proteinases. Key Words: Dental enamel, Birefringence, Bisphosphonates, Phenanthroline, Phenylmethylsulphonyl Fluoride / Doutorado / Histologia e Embriologia / Doutor em Biologia Buco-Dental

The search for more effective treatment strategies in melanoma led to many new innovative approaches aiming at different molecular targets. Chemotherapy still remains the most effective treatment and many efforts are put in order to improve targeting and delivery of the chemotherapeutic agents. Among these, peptide conjugates of anticancer drugs were designed to increase stability, cell penetration, specificity and accumulation in cancer cells. We as well as others evaluated such a conjugate, termed PSF (L-prolyl-m-L-sarcolysyl-L-p-fluorophenylalanine-ethylester) in terms of its cytotoxicity in vitro and in vivo using a human melanoma tumor as a model, its stability, transport, and metabolisation. <p>By comparing the cytotoxicity of PSF and melphalan towards different cancer primary melanoma cell cultures, we noticed some interesting observations: PSF displayed the same toxicity pattern both in short (2h) and long term (24h) cell exposures whereas melphalan and m-sarcolysin needed long term exposure to reach the same toxicity. This could indicate that PSF very quickly penetrates the cells in accordance with what has been shown with red blood cells (RBCs). PSF has shown a much better and quicker penetration into the cells in vitro as compared to melphalan. <p>In this present work, the cytotoxic effect of PSF was further evaluated in vivo using a standardized nude mice tumor model bearing a human melanoma. First, the acute toxicity in rats and mice and the maximum tolerated dose were determined. After a dose-escalation study one dose was singled out and tested as a single dose and as a fractionated dose. PSF was able to reach the tumor site and a dose-response relationship was observed. The IP administration of fractionated doses of PSF had significantly better effect on tumor growth inhibition, regression and regrowth than single dose administration and this without any evidence for general toxicity monitored by animal weight loss. We also compared the efficacy of PSF to its parent drug m-sarcolysin, melphalan and cyclophosphamide and observed that PSF was much more active than both melphalan and m-sarcolysin at the same molar doses.<p>Body distribution of the 14C-labelled PSF revealed ratios of 2.4 and 1.5 compared to muscle tissue for the two melanoma tumors evaluated with no significant and stable accumulation in any vital organ. The amount of tracer was still high in the blood after 24 hours explaining the high radioactivity in the kidney and partly in the liver. Interestingly, the spleen had an unusual high radioactivity uptake reflecting the exceptional binding of the tracer to blood cells (BC), while the pancreas very high load was an indicator of protease-mediated specific delivery and strongly support our hypothesis elaborated on the basis of in vitro results. <p><p>Our in vitro data point to a particular mechanism of action of PSF based on the transport of PSF through the body by the rapid binding to blood cells and the delivery at the tumor site by the subsequent release of its active metabolites due to cleavage by tumor-associated proteases.<p>Concerning the binding of PSF to membranes and its transport the following observations were made: while PSF was stable in human plasma, it disappeared very quickly in whole blood along with the generation of a main metabolite: m-sarcolysin. The presence of BC membranes was required for both binding and generating the metabolites. Binding to natural or artificial membranes was achieved and only competition with melanoma cells or proteolytic enzymes such as dispase, led to the generation of active metabolites. The different metabolites were isolated using preparative LC and were then identified using Electrospray Ionisation Mass Spectrometry (ESI). Three metabolites, of which m-sarcolysin was the main one, were identified all bearing the chloroethyl alkylating group. <p>Enzymatic catalysis was further supported by a set of experiments where the enzymatic activity was non-specifically and specifically inhibited. In order to look at the effect of extracellular matrix proteases on PSF, three representatives of ECM proteases were incubated with PSF: collagenase A had no effect, but both dispase and trypsine were able to process PSF. <p>The following data indicate the higher processing of PSF in the presence of cells with a higher proteolytic activity and thus the delivery of the blood cell-bound PSF. When comparing BC with melanoma cells (MC), the latter showed a higher ability to bind and process PSF both by membrane-associated and most interestingly soluble proteases. A lot of families of enzymes are reported to be overexpressed by melanoma cells including: metalloproteases, cysteine cathepsins, serine proteases and aminopeptidases. All the melanoma cells and cell lines evaluated were able to generate PSF active metabolites. <p>To identify the families of enzymes expressed on the membrane of melanoma cells that might be involved in the mechanism of action of PSF, we performed 2D-gel electrophoresis on their membrane extracts. The 2D-gels experiments revealed the presence of proteins compatible with enzymes known to be important in melanoma and further work is needed to identify the individual enzymes involved by using mass spectrometry and Western blotting. <p><p>Both our in vitro and in vivo findings strongly suggest that not only melanoma tumor cells and tumor sites but other types of tumors as well may be targets for the toxic activity of PSF owing to their much higher load in proteolytic enzymes that are closely related to their invasive potential. The transport of PSF by the blood cells and the release of its metabolites at the tumor site result in a low amount of drug in its free soluble form within the blood and this may explain the relatively lower side-effects observed. PSF is thus expected to have a much better therapeutic index than conventional alkylating agents. This original mechanism of drug delivery may well be extended to other cancer and non-cancer drugs than alkylating agents.<p> / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished