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Measurement of fish consumption in population-based studies of cancer /Mina, Kym Deanne. January 2007 (has links)
Thesis (Ph.D.)--University of Western Australia, 2007.
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Cyclic GMP-stimulated phosphodiesterase isoforms : distinct subcellular distribution, localization in mouse brain, and identification of a novel olfactory signaling pathway /Juilfs, Dawn Marie, January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [114]-130).
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Type VII phosphodiesterase in regulation of T cell function /Li, Linsong, January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 81-91).
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Klonierung und Charakterisierung der Flavonoid 3'-Hydroxylase und der Flavonoid 3',5'-HydroxylaseEder, Christian. January 2001 (has links) (PDF)
München, Techn. Univ., Diss., 2001. / Computerdatei im Fernzugriff.
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Klonierung und Charakterisierung der Flavonoid 3'-Hydroxylase und der Flavonoid 3',5'-HydroxylaseEder, Christian. January 2001 (has links) (PDF)
München, Techn. Universiẗat, Diss., 2001.
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Η συνδεκάνη-3 διαμεσολαβεί τις βιολογικές δράσεις της HARPΚίτσου, Παρασκευή 07 October 2011 (has links)
Η HARP (Heparin Affin Regulatory Peptide) είναι ένας αυξητικός παράγοντας ο οποίος εμφανίζει πλειάδα βιολογικών δράσεων εμπλεκόμενος στη διαφοροποίηση, τον πολλαπλασιασμό και τη μετανάστευση πολλών τύπων κυττάρων, καθώς και στην αγγειογένεση και την ανάπτυξη όγκων. Η HARP έχει χρονοειδικό και ιστοειδικό πρότυπο έκφρασης, υπερεκφράζεται όμως σε καρκινικές κυτταρικές σειρές, σε ανθρώπινους καρκινικούς όγκους και βρίσκεται σε υψηλή συγκέντρωση στον ορό του αίματος ασθενών με διάφορες μορφές καρκίνου. Η HARP ασκεί τις βιολογικές της δράσεις μετά από δέσμευση στους διαμεμβρανικούς υποδοχείς, SDC3, ALK και RPTPβ/ζ. Οι βιολογικές της δράσεις προσδιορίζονται από τη συνισταμένη των δράσεων που έχει κάθε υποδοχέας της, αντικατοπτρίζοντας τον περίπλοκο μηχανισμό δράσης της.
Στη συγκεκριμένη εργασία μελετήσαμε τον τρόπο με τον οποίο η SDC3 διαμεσολαβεί τις βιολογικές δράσεις της HARP σε κύτταρα DU145 και PC3, κυτταρικές σειρές από καρκίνο ανθρώπινου προστάτη. Χρησιμοποιώντας την RNAi τεχνολογία, διαμολύναμε παροδικά τα κύτταρα με siRNA ειδικά σχεδιασμένο έναντι της SDC3, μειώνοντας τα επίπεδα έκφρασης της.
Καλλιεργήσαμε κύτταρα, φυσιολογικά και μετασχηματισμένα, επιδράσαμε εξωγενώς με HARP και τα αποτελέσματα έδειξαν ότι και στις δύο καρκινικές κυτταρικές σειρές, η SDC3 είναι θετικός ρυθμιστής της επαγόμενης από τη HARP κυτταρικής προσκόλλησης και μετανάστευσης.
Παράλληλα, μελετήσαμε την ενεργοποίηση μορίων που εμπλέκονται στο μονοπάτι μεταγωγής σήματος της SDC3 όπως της Src, Fak, Akt, Pten και Erk1/2. Τα αποτελέσματα έδειξαν ότι η ενεργοποίησή της SDC3 από τη HARP οδηγεί στην αύξηση των επιπέδων των pSrc, pFak, pAkt και p Erk1/2, ενώ, βρέθηκε ότι μειώνεται η φωσφορυλίωση της Pten.
Συμπερασματικά, στην παρούσα εργασία μελετήθηκε η συμμετοχή της συνδεκάνης 3 στις βιολογικές δράσεις της HARP, καθώς και μόρια του σηματοδοτικού μονοπατιού μεταγωγής σήματος του υποδοχέα αυτού. Βρέθηκε ότι η HARP προσδενόμενη στον υποδοχέα αυτό, επάγει την προσκόλληση και μετανάστευση των κυττάρων, δράσεις που συνδέονται με την ανάπτυξη όγκων και τη μετάσταση καρκινικών κυττάρων. / HARP (Heparin Affin Regulatory Peptide), also known as Pleiotrophin, is a growth factor involved in several biological actions such as induction of cellular proliferation, migration and angiogenesis. Elevated concentrations of this growth factor are found in many tumours, as well as in the plasma of patients with different types of cancer. HARP exerts its actions after binding to the transmembrane receptors RPTP β/ζ, ALK and N-Syndecan (SDC3).
In the present work, we studied the role of the transmembrane receptor SDC3 in the biological actions of HARP. We used DU145 and PC3 transiently transfected with specific siRNA to downregulate the accumulation of SDC3. Our results show that HARP binds to SDC3 and induces the cell adhesion and migration of DU145 and PC3 cells. We also studied the signal transduction through SDC3 receptor and the activation of signaling molecules such as Src, Fak, Akt, Pten and Erk 1/2. Our results revealed that HARP induces the phosphorylation of Src kinase, Fak and Erk1/2 after binding to SDC3 in both DU145 and PC3 cells. Also, HARP increases Akt signaling cascade in PC3 cells, while it suppresses the signaling cascade induced by PTEN in DU145 cells. Consequently, HARP interaction with SDC3, results in the activation of SDC3, which in turn triggers a signal transduction pathway that leads to specific biological cell responses activates other cytoplasmic effectors. Therefore, there starts a signaling cascade that targets specific genes and cell response.
In conclusion, our results indicate that SDC3 contributes, as a positive regulator, to HARP-dependent cell adhesion and migration in both DU145 and PC3 cells.
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"...allt som händer i samhället speglas av i skolan" : En studie om undervisning inom religionskunskap i relation till ett mångkulturellt samhälleÖstensson, Sofia January 2015 (has links)
The aim of this study is to investigate how a multicultural society can be reflected in the religious education. This essay will compare how teachers in grade 3 reflects about their religious education in relation to the society’s cultural diversity and it will also analyze how the teachers’ pupils think about religion. I have used the following questions: Do the teachers believe that the cultural diversity affects their religious education and if so, how and in what way? How do the teachers describe teaching religion in relation to the multicultural society? What are the pupils’ perceptions of religion in a context of cultural diversity? The investigation is based on qualitative semi-structured interviews with four different teachers and a questionnaire study with 62 pupils that generates both quantitative and qualitative data. The theoretical approach of the study is grounded on different definitions of religion and on a theory called frame factor theory which was produced by Urban Dahllöf. The result of the study shows that the teachers believe that it is important to adapt their religious education to the cultural diversity. When comparing the teachers’ descriptions about their religious education it shows that all of the teachers describe factors that can influence their teaching of religion in a multicultural society. The questionnaire study shows similarities and differences in the way pupils think about religion but the most common thing is that most of the pupils associate God with religion.
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Implicações da variante da cadeia CD11b (rs1143679) do CR3 para a liberação da mieloperoxidase de neutrófilos humanos / Implications of the CD11b chain variant (rs1143679) of CR3 for the release of myeloperoxidase in human neutrophilsJoão Rodrigues Lima Júnior 13 March 2015 (has links)
O neutrófilo é a célula predominante no sangue circulante e medeia as primeiras respostas da imunidade inata contra infecções, graças a sua capacidade de fagocitar e destruir patógenos. A mieloperoxidase (MPO) é a proteína mais abundante do neutrófilo e a sua potente atividade microbicida está relacionada à sua participação na geração de moléculas oxidantes capazes de degradar uma ampla variedade de estruturas biológicas. Contudo, à MPO também tem sido atribuído um papel deletério nos processos inflamatórios por mediar danos ao endotélio e amplificar a inflamação. A liberação da MPO do neutrófilo diretamente sobre o endotélio depende da interação célula-célula mediada pela integrina CD11b/CD18 (também conhecida como receptor do complemento tipo 3, CR3) expressa nos neutrófilos e pela molécula de adesão intercelular-1 (ICAM-1) no endotélio, sugerindo um papel importante para o CR3 em mediar o dano tecidual em condições inflamatórias crônicas. A cadeia CD11b (?M) do CR3 é codificada pelo gene ITGAM (Integrin Alpha M) e um polimorfismo devido à troca de um único nucleotídeo, G328A, resulta na substituição de uma arginina por uma histidina na posição 77 no domínio extracelular da molécula CD11b, levando à existência de duas variantes polimórficas (R77 e 77H). Este polimorfismo recebe o número de referência rs1143679. A variante 77H está associada à suscetibilidade ao lúpus eritematoso sistêmico (LES), mas o comprometimento funcional desta variante ainda não é compreendido. Neste contexto, o objetivo deste estudo foi avaliar se o polimorfismo da cadeia CD11b influencia o burst oxidativo dependente de MPO em neutrófilos humanos de indivíduos saudáveis. Os genótipos foram determinados por reação em cadeia da polimerase para identificação das variantes alélicas; os neutrófilos foram estimulados com zimosan opsonizado com soro humano normal; a expressão do CR3 foi avaliada por citometria de fluxo com anticorpo monoclonal específico; a avaliação da atividade da enzima MPO foi realizada através da quantificação indireta de seu produto, o ácido hipocloroso, pelo método da taurina-cloramina; o burst oxidativo foi medido por quimioluminescência (QL) dependente de luminol e de lucigenina. Não houve diferença estatística na atividade da MPO entre os grupos, contudo a presença da variante 77H nos neutrófilos mostrou uma menor liberação de MPO quando comparada aquela de neutrófilos com a variante R77. Esta diminuição da liberação da MPO não foi relacionada à diferença de expressão do CR3, uma vez que a análise da expressão do CR3 nos neutrófilos não mostrou diferenças entre os grupos. Nenhuma diferença foi observada na medida de QL. Levando-se em consideração as funções imunomodulatórias da MPO, dependentes e independentes da sua atividade catalítica, nas interações entre neutrófilo e endotélio mediadas pelo CR3, nosso resultado mostra a necessidade de investigar se pequenas diferenças entre a liberação de MPO por neutrófilos, expressando a variante 77H da cadeia CD11b, pode explicar a associação deste polimorfismo com a suscetibilidade ao LES e/ou outras doenças. / The neutrophils are the predominant cells in the circulating blood and mediates the first responses of innate immunity against infections, thanks to their ability to phagocyte and destroy pathogens. The myeloperoxidase (MPO) is the most abundant protein in the neutrophils and its potent microbicidal activity is related to its participation in the generation of oxidant molecules capable of degrading a wide variety of biological structures. However, the MPO has also been attributed a deleterious role in mediating inflammatory processes at endothelial damage and amplifying inflammation. The release of MPO from neutrophils depends directly on the endothelial cell-cell interaction mediated by the integrin CD11b / CD18 (also known as the complement receptor type 3, CR3) expressed in neutrophils and the intercellular adhesion molecule-1 (ICAM-1) in the endothelium, suggesting an important role for CR3 in mediating tissue damage in chronic inflammatory conditions. The CD11b chain (?M) of CR3 is encoded by the gene ITGAM (Integrin Alpha M) and a polymorphism due to the exchange of a single nucleotide, G328A, results in the substitution of an arginine by a histidine at position 77 in the extracellular domain of the CD11b molecule, leading to the existence of two polymorphic variants (R77 and 77H). This polymorphism receives the reference numeral rs1143679. The 77H variant is associated with susceptibility to systemic lupus erythematosus (SLE), but the functional impairment of this variant is not yet understood. In this context, the aim of this study was to evaluate the polymorphism of the CD11b chain influences the oxidative burst dependent MPO in human neutrophils from healthy individuals. The genotypes were determined by polymerase chain reaction to identify the allelic variants; neutrophils were stimulated with opsonized zymosan with normal human serum; of CR3 expression was assessed by flow cytometry with specific monoclonal antibody; evaluating the MPO enzyme activity was performed by indirect measurement of your product, hypochlorous acid, the method of taurine-chloramine; The oxidative burst was measured by chemiluminescence (Q) dependent luminol and lucigenin. There was no statistical difference in MPO activity between the groups, but the presence of the 77H variant in neutrophils showed a lower release of MPO compared that of neutrophils with the R77 variant. This reduction of MPO release was not related to the difference CR3 expression, since the analysis of CR3 expression on neutrophils showed no differences between groups. No difference was observed in the extent of QL. Taking into account the immunomodulatory functions of MPO-dependent and independent of its catalytic activity, interactions between neutrophils and the endothelium mediated CR3, our result shows the need to investigate whether small differences between the MPO release by neutrophils, expressing the variant 77H of the CD11b chain, may explain the association of this polymorphism with susceptibility to SLE and / or other diseases.
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Caracterização molecular de Dengue tipo 3 isolados no Brasil e no Paraguai / Molecular characterization of dengue type 3 isolated in Brazilian and ParaguayHelda Liz Alfonso Castro 15 October 2010 (has links)
RESUMO Alfonso Castro, H. L. Caracterização molecular de dengue tipo 3 isolados no Brasil e no Paraguai. 2010. 105f. Dissertação (Mestrado). Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto, 2010. O vírus da dengue (DENV), pertencente ao gênero Flavivirus da família Flaviviridae, é a arbovirose de maior impacto em saúde pública na atualidade. A infecção com qualquer do quatro sorotipos de dengue (DENV-1, -2, -3 e -4) pode ser assintomática ou causar doença febril (DF) que pode evoluir para uma forma mais grave, e algumas vezes fatais, caracterizada por derrame capilar, trombocitopenia. A introdução do DENV-3, genótipo III, nas Américas coincidiu com um aumento no número de casos graves da doença. Este vírus causou uma grande epidemia em 2002 no Rio de Janeiro e posteriormente se espalho em todas as regiões do pais, chegando inclusiva ao Paraguai. Diversos estudos filogenéticos e evolutivos foram realizados com o DENV-3 nas Américas, mas utilizando sequências genômicas parciais. Neste trabalho temos por objetivo analisar o relacionamento filogenético e evolutivo de DENV-3 isolados no Brasil e no Paraguai analisando a sequência genômica completa. A sequência de vírus isolados no Brasil (n=9) e no Paraguai (n=3) foram comparadas com 527 sequências depositadas no GenBank. As 12 cepas virais isoladas no Brasil e no Paraguai pertencem ao grupo americano do genótipo III. Analisando a árvore filogenética dos DENV-3 observamos três genótipos e diversas linhagens, sub-linhagens e clados dentro de cada genótipo. A distância genética entre os genótipos foi de 7,3 a 7,5%, entre as linhagens de 3,2 a 5,3%, entre as sub-linhagens 2,5 a 3,2% e entre os clados de 1,0 a 1,9%. A taxa evolutiva dos vírus variou entre 1,2x10-4 a 8,2x10-4 subs/sitio/ano. O ancestral comum do genótipo I teria surgido entre 1849-1945, do genótipo II entre 1916-1960, e do genótipo III entre 1876-1923. Os diferentes grupos genéticos apresentam motif de aminoácidos característicos. Estes dados serão de grande utilidade para uma melhor caracterização dos DENV-3 em futuras epidemias e, inclusive, poderão ser utilizados para seleção de candidatos a vacina. / ALFONSO CASTRO, H. L. Molecular characterization of dengue type 3 isolated in Brazilian and Paraguay. 2010. 105f. Dissertation (Master). Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto, 2010. Infections of humans with dengue viruses (DENV), which belong to the genus Flavivirus(family, Flaviviridae), can be subclinical or cause illnesses ranging from a mild, flu-like syndrome with rash (dengue fever [DF]) to a severe and some times fatal disease, characterized by capillary leakage, thrombocytopenia, and sometimes hypovolemic shock (hemorrhagic dengue fever [DHF/DSS]). DENV are classified in four immunological distinct serotypes: DENV-1 to 4. Recently, a dramatically increase of DHF/DSS cases in the Americas have bee see, and this increase coincided with the introduction of the dengue virus type 3, genotype III. This virus causes a great epidemic in 2002 in the city of Rio de Janeiro and later, the virus spread in Paraguay. Phylogenetics and evolutionary studies have bee carried out with DENV-3 isolated worldwide, but using sequences partial genomic. In this work, we have analyzed the genetic diversity of DENV-3 of Brazilian and Paraguayan isolated, analyzing the complete sequences genomic. The Brazilian (n=9) and Paraguayan (n=3) isolated, were compared with 527 sequences deposited in the GeneBank. Theses isolated, belong to the American group of the genotype III. The phylogenetic analysis of complete genome of the DENV-3, confirmed the existence of three known genotypes and suggested the presence of other groups within each genotype named of the lineages, sub-lineages and clades. The genetic distance among the genotypes were of 7,3 to 7,5%, among the lineages of 3,2 to 5,3%, among the sub-lineages of 2,5 to 3,2% and among clades of 1,0 to 1,9%. The evolutionary rates of the viruses varied among 1,2x10-4 to 8,2x10-4 s/s/y. The age of the ancestral common more recent of the genotype I, possibly are among 1849-1945, the ancestral common of the genotype II, among 1916-1960 and the ancestral common more recent of the genotype III, among 1876-1923. The different genetic groups present motif of amino acids. These data could provide information for a better understanding of the evolution of theses viruses, and even for selection of candidate vaccine
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Efeitos da ingestão de simbiótico e indol-3-carbinol sobre o processo de carcinogênese química de cólon em ratos Wistar alimentados com dieta contendo heme / Effects of synbiotics and indol-3 carbinol intake on colon carcinogenesis in hemin-fed ratsMoura, Nelci Antunes de [UNESP] 18 December 2015 (has links)
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Previous issue date: 2015-12-18 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O ferro heme presente na carne vermelha está associado ao aumento da incidência do câncer colorretal (CCR). O heme pode catalisar a formação de compostos nitrosos e a peroxidação lipídica no lúmen intestinal. No entanto, os efeitos pró-carcinogênicos do heme podem ser inibidos por alguns compostos como os sais de cálcio, clorofila entre outros. Sabe-se que o indol-3-carbinol (I3C), presente nas plantas da família das Brassicas e os simbióticos são compostos promissores na prevenção do câncer de cólon, atuando em via de proliferação, apoptose e modulação da microbiota intestinal. Dessa forma, o objetivo desse estudo foi o de avaliar os efeitos da ingestão de simbiótico (prebiótico inulina associado ao probiótico Bifidobacterium lactis bb-12) e de I3C, isolados ou em associação sobre o processo de carcinogênese de cólon induzido pela 1,2-dimetilhidrazina (DMH) em ratos Wistar alimentados ou não com dieta suplementada com heme. Os animais foram alocados em 9 grupos, os grupos 1 a 8 (n=12) receberam quatro doses de DMH (40 mg/Kg) nas duas semanas iniciais do experimento. Os grupos 1 e 9 (n=12 e 5) receberam ração basal até o final do experimento e os grupos 2 a 8 receberam ração basal suplementada com heme, heme+I3C, heme+simbiótico, heme+I3C+simbiótico, I3C, simbiótico e I3C+simbiótico, respectivamente. A eutanásia ocorreu ao final da 25ª semana. Neste momento foi realizada a coleta do cólon com os respectivos tumores e amostras de fezes do ceco. Em seguida, procedeu-se a medida dos tumores e coleta de amostras para biologia molecular. Após a fixação em formalina tamponada e a retirada dos tumores, realizou-se a contagem de focos de criptas aberrantes (FCA) pela coloração de azul de metileno. Realizou-se a análise histológica dos tumores e a análise da expressão de 95 genes relacionados a via da carcinogênese colônica, pela técnica Taqman Low Density Array, e a expressão proteica da E-caderina, TGFB1 (Transforming growth factor beta 1) e RAF1 (Serine/threonine-protein kinase) por Western Blotting. Foram analisados os índices de proliferação celular e apoptose pelo PCNA (Proliferating cell nuclear antigen) e caspase 3-clivada, respectivamente, tanto nos cólons como em tumores, e a expressão de β-catenina e E-caderina nos tumores, por imunoistoquímica. Células da linhagem Caco-2 foram incubadas com água fecal extraída das fezes do ceco e submetidas a testes de citotoxicidade e genotoxidade pelos testes do MTT (mitochondrial tetrazolium test) e Cometa, respectivamente. Os dados foram comparados utilizando-se o software Sigma Stat 3.5 e Expression Suíte para expressão gênica. Foi observado aumento significativo no número de criptas aberrantes (CA) no grupo que recebeu heme (G2) quando comparado ao grupo que recebeu apenas ração basal (G1). Redução significativa no número de CA foi observada no grupo que recebeu heme+I3C (G3) e heme+simbiótico (G4) quando comparado ao grupo que recebeu heme (G2). O número de FCA totais com ≥ 9 criptas aberrantes foi significativamente menor no grupo que recebeu heme+simbiótico (G4) quando comparado ao grupo que recebeu heme (G2). Entretanto, aumento significativo no número de tumores com mais de 60 mm3 foi observado no grupo suplementado com heme+I3C+simbiótico (G5), quando comparado ao grupo que recebeu heme (G2). Além disso, foi observado aumento significativo na incidência de tumores invasivos no grupo que recebeu heme+I3C+simbiótico (G5) quando comparado ao grupo que recebeu heme (G2). Os tumores do grupo suplementado com heme+I3C+simbiótico (G5) apresentaram baixa expressão dos genes Cdh1, Tgfb1, Appl1 e alta expressão do Raf1, já os tumores do grupo suplementado com heme +I3C (G3) apresentaram baixa expressão do Cdh1. A água fecal do grupo que recebeu heme (G2) apresentou significativamente maior citotoxicidade e genotoxicidade quando comparado ao grupo que recebeu ração basal (G1). Com relação aos tratamentos, a água fecal do grupo que recebeu heme+I3C (G3) e heme e simbiótico (G4) apresentaram água fecal significativamente com menor potencial genotóxico quando comparada ao grupo que recebeu heme (G2). No entanto, o grupo que recebeu heme+I3C+simbiótico (G5) apresentou aumento significativo na genotoxicidade da água fecal. Dessa forma, concluímos que o heme associado a uma dieta com níveis normais de cálcio não é um potente indutor de FCA, mas aumenta a citotoxicidade e genotoxicidade da água fecal. No entanto, tanto o I3C como o simbiótico reduzem os efeitos citotóxicos/genotóxicos da ingestão de heme. Contudo, a associação do heme+I3C+simbiótico apresentou efeito promotor da carcinogênese de cólon. / Colorectal cancer (CRC) is the third most common type of cancer worldwide. Hemin iron, which is found in red meat, catalyzes the formation of carcinogenic N-nitroso compounds and lipid peroxidation end-products in the colon lumen. The procarcinogenic effect of hemin is known to be inhibited by molecules, such as calcium, chlorophyll and others. However, the preventive effect of indole 3-carbinol and synbiotics on colon carcinogenesis remains uninvestigated. The aim of this study was to assess the modifying effects of a synbiotic (inulin+ Bifidobacterium lactis) and/or I3C against dimethylhidrazine (DMH)-induced colon carcinogenesis in hemin-fed male Wistar rats. Nine groups of animals were evaluated. Groups 1–8 received a total of four s.c. DMH injections (40 mg/kg b.w.) over 2 weeks, whereas group 9 was given EDTA solution (vehicle). Two weeks after DMH-initiation, G1 and G9 were fed a basal diet while groups G2, G3, G4, G5, G6, G7 and G8 received a basal diet containing hemin, hemin+I3C, hemin+synbiotic, hemin+I3C+synbiotic, I3C, synbiotic and I3C+synbiotic, respectively, during 23 weeks. At 25 week, all animals were killed and their colons were removed. Cecal contents were collected to determine fecal water cytotoxicity and genotoxicity (DNA damage) in Caco-2 cells. Colon tumors were measured and samples were collected and stored at -800C. The colons were fixed flat in 10% buffered formalin for 24 h and stained with 1.0% methylene blue for classical ACF analysis and quantification. Tumor incidence and multiplicity were assessed after histopathological analysis. Gene and protein expression were determined in tumor samples alone. The total number of aberrant crypts (AC) was significantly higher (p= 0.03) in the hemin group (G2) than in the group fed basal diet (G1). AC number in both hemin+I3C (G3) and hemin+synbiotic (G4) groups was also significantly lower than in the group fed hemin (G2). Tumor volume was higher in the hemin+I3C+ synbiotic (G5) group and invasive adenocarcinoma was more frequent in the hemin+I3C+synbiotic group (G5) than in the group fed hemin (G2). Colon tumor expression analysis showed that in comparison with the group fed hemin (G2), Cdh1, Tgfb1 and Appl1 were downregulated while Raf1 was upregulated in the group hemin+I3C+synbiotic (G5), and Cdh1 was down-regulated in the group hemin+I3C (G3). Fecal water cytotoxicity in the hemin group (G2) was higher than in groups fed basal diet (G1) and hemin+I3C (G3). Fecal water genotoxicity was also significantly higher in the group fed hemin alone (G2) than in the basal diet group (G1), as well as, in groups fed hemin+I3C (G3) and hemin+synbiotics (G4). However, when compared to hemin alone (G2), fecal water from group hemin+I3C+ synbiotics (G5) presented the highest DNA damage levels. Our results suggest that although hemin in a regular-calcium diet was not a powerful ACF promoter, it increased fecal water citotoxicity and genotoxicity. On the other hand, hemin associated with either I3C or synbiotics prevented ACF promotion. Nonetheless, a synergistic interaction among hemin, I3C and synbiotic did promote DMH-induced tumorigenesis. / FAPESP: 2011/23699-4
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