Colon cancer is the third most common type of cancer, with high mortality throughout the world. During tumorigenesis, normal cells transform into tumour cells following changes in the expression of oncogenes and/or tumour suppressor genes, which are involved in many processes including the cell cycle, differentiation and apoptosis. An imbalance in the regulation of proliferation and differentiation in colon epithelial cells is usually associated with the development of colon cancers. Uncontrolled proliferation with a lack of differentiation is one of the major characteristic features of cancer cells and a remodelling of the Ca2+ signalling is linked to these pathways. Among the Ca2+ transporting proteins, P-type Ca2+-ATPases, the plasma membrane Ca2+ ATPase (PMCA) pump, has a high-affinity for Ca2+ and is involved in the efflux of Ca2+ against the electrochemical gradient from the cytosol across the extracellular space. Four PMCA isoforms have been identified. PMCA1 and 4 are expressed in most tissues. Changes in the expression of PMCA have been documented in breast cancer cells, whereas the expression profile of PMCA isoforms in colon cancer cells remains unknown. Up-regulation of another P-type Ca2+-ATPase, expressed in the endoplasmic reticulum, SERCA3, occurs during the differentiation of colon cancer cell lines and is down-regulated in colon cancers. Changes in PMCA expression have not been assessed during colon cancer cell differentiation. The first part of this thesis describes the analysis of the expression profile of PMCA during colon cancer cell differentiation. Both PMCA mRNA and protein levels were assessed in differentiated HT-29 cells by real time RT-PCR and western blotting analysis, respectively. The results showed changes in PMCA4 expression, whereas changes in the expression of PMCA1 were not associated with differentiation of HT-29 cells. PMCA mRNA levels were also reduced in some colon cancers suggesting a remodelling of PMCA-mediated Ca2+ efflux during colon carcinogenesis. The second part of this thesis involved exploring the functional role of PMCA4 in Ca2+-mediated signalling pathways such as differentiation, proliferation and apoptosis. PMCA4 expression was altered in HT-29 colon cancer cells via transient and stable over-expression of a PMCA4 expressing plasmid or siRNA-mediated silencing of PMCA4. An increase in the PMCA4 level did not alter or induce differentiation of HT-29 cells. Hence, up-regulation of PMCA4 expression may be a consequence rather than a cause of HT-29 colon cancer cell differentiation. PMCA4-mediated reduction in proliferation was observed in HT-29 colon cancer cells where PMCA4 was stably over-expressed. Stable PMCA4 over-expression was also associated with the down-regulation of the transcription of the early response gene, FOS. Despite the apparent augmentation of cytosolic Ca2+ responses to G-protein coupled receptor Ca2+ mobilizing agents, the sensitivity of cells to the apoptotic inducing agents such as TRAIL and/or CCCP was not affected following siRNA-mediated PMCA4 inhibition in HT-29 cells. Collectively this thesis describes PMCA isoform-specific changes during differentiation of HT-29 colon cancer cells and alterations in PMCA levels in some colon cancers.Evidence is also presented to suggest that alterations in PMCA expression in colon cancer cells may provide a growth advantage by promoting proliferation without increasing sensitivity to apoptotic stimuli.

No description available.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-01T12:09:03Z No. of bitstreams: 1 ingridestevampereira.pdf: 2004254 bytes, checksum: 326e3188dc98d9fc4ddc417af89ebc1e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-02T15:12:44Z (GMT) No. of bitstreams: 1 ingridestevampereira.pdf: 2004254 bytes, checksum: 326e3188dc98d9fc4ddc417af89ebc1e (MD5) / Made available in DSpace on 2017-06-02T15:12:44Z (GMT). No. of bitstreams: 1 ingridestevampereira.pdf: 2004254 bytes, checksum: 326e3188dc98d9fc4ddc417af89ebc1e (MD5) Previous issue date: 2017-02-22 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / A talidomida é uma potente droga anti-inflamatória empregada no tratamento de diversas patologias, incluindo Eritema Nodoso Leproso (ENL), câncer, doença de Crohn e outras desordens inflamatórias e vasculares. Entretanto, seus efeitos tóxicos e teratogênicos tornam sua utilização limitada e motivam pesquisas para a síntese de análogos que apresentem eficácia semelhante na imunomodulação, sem efeitos tóxicos. Diversos análogos da talidomida vêm sendo desenvolvidos no laboratório de química da UFJF. Em estudos anteriores, mostramos que a introdução de dois anidridos ftálicos na composição aumenta significativamente a atividade biológica e solubilidade em água do composto, sem aumento da toxicidade em modelos experimentais in vitro e in vivo. O presente trabalho visa a síntese de dois novos compostos análogos da talidomida, CAT-15 e CAT-16, formados por apenas um derivado anidrido ftálico aberto, mantendo um grupo amino livre, e a avaliação da sua atividade anti-inflamatória utilizando linhagem de célula HT-29 e células mononucleares de sangue periférico humano (PBMC) estimuladas com LPS. A citotoxicidade dos compostos foi avaliada pelo ensaio do MTT, com tratamento por 18 horas para células HT-29 e por 24 e 48 horas para PBMC, usando concentrações crescentes de talidomida, CAT-15, CAT-16. A dexametasona foi utilizada como controle positivo. A produção de TNF-α, CXCL-10, IL-6, IL-8 e IL-10 foi avaliada pelo método de ELISA. Os novos compostos não foram tóxicos para as células HT-29 e PBMC em nenhuma das concentrações testadas, com exceção de CAT-16 a 1600µM. Células HT-29 produziram grande quantidade de CXCL-10 em resposta ao LPS e os resultados deste trabalho mostram que a talidomida e os análogos CAT-16 e CAT-15 apresentam atividade inibitória sobre a produção desta quimiocina. O composto CAT-16 modulou a produção de CXCL-10 em concentrações menores que a talidomida em ambos os modelos de tratamento (simultâneo e prétratamento). Em contrapartida, a modulação por CAT-15 foi observada apenas no modelo de pré-tratamento. Com relação a IL-8, a talidomida e o CAT-16 inibiram a produção desta citocina por células HT-29 apenas na concentração de 100µM. Ao contrário das células HT-29, o PBMC produziu TNF-α em resposta ao LPS, tendo a talidomida e o análogo CAT-16 apresentado capacidade de inibição da produção do TNF-α em ambos os tempos de tratamento. O análogo CAT-15 não influenciou a produção de TNF-α por PBMC em nenhuma das concentrações e tempos de tratamento. Este estudo também mostra a atividade da talidomida e dos nos análogos sobre a produção de IL-6 e IL-10 por PBMC, havendo significativa inibição da produção de IL-6 por todos os compostos e tempos de tratamento e sobre IL-10 pelo composto CAT-15 após 48 horas de incubação. Nossos resultados sugerem a aplicabilidade dos novos compostos, CAT-15 e CAT-16, no controle de respostas inflamatórias uma vez que inibiram a produção de moléculas chave como TNF-α, IL6, IL-10, IL-8 e CXCL-10. Ainda, esses compostos possuem estruturas simplificadas, têm baixo custo de produção, são hidrossolúveis e não possuem centro quiral. Esses resultados podem contribuir no desenvolvimento de novas estratégias de tratamento para certas condições inflamatórias. / Thalidomide is a potent anti-inflammatory drug used in the treatment of various pathologies including Erythema Nodosum Leprosum (ENL), cancer, Crohn's disease and other inflammatory and vascular disorders. However, its toxic and teratogenic effects make its use limited and motivate research groups to synthesize analogues presenting similar immunomodulation efficacy, without toxic effects. Several analogs of thalidomide have been developed in the laboratory of chemistry of the UFJF. Previously, we have shown that introduction of two phthalic anhydrides into the composition significantly enhances biological activity and water solubility, without enhanced toxicity. The present work aims at the synthesis of two new analogues of thalidomide, CAT-15 and CAT-16, formed by only one open phthalic anhydride derivative, maintaining a free amino group, and the evaluation of its anti-inflammatory activity using HT- 29 and human peripheral blood mononuclear cells (PBMCs) stimulated with LPS. The cytotoxicity of the compounds was evaluated by the MTT assay, with 18 hours treatment for HT-29 cells and for 24 and 48 hours for PBMC, using increasing concentrations of thalidomide, CAT-15, CAT-16. Dexamethasone was used as a positive control. Production of TNF-α, CXCL-10, IL-6, IL-8 and IL-10 was evaluated by the ELISA method. The novel compounds were not toxic to HT-29 and PBMC cells at any of the concentrations tested, with the exception of CAT-16 at 1600μM. HT-29 cells produced large amounts of CXCL-10 in response to LPS and the results of this work show that thalidomide and the CAT-15 and CAT-16 analogs exhibit inhibitory activity on the production of this chemokine. CAT-16 compound modulated the production of CXCL-10 at lower concentrations than thalidomide in both treatment models (simultaneous and pretreatment). In contrast, CAT-15 modulation was observed only in the pre-treatment model. Regarding IL-8, thalidomide and CAT-16 inhibited their production by HT-29 cells only at the concentration of 100 μM. Unlike HT-29 cells, PBMC produced TNF-α in response to LPS, with thalidomide and CAT-16 analog being able to inhibit TNF- production at both treatment times. The CAT-15 analogue did not influence the production of TNF-α by PBMC at any of the concentrations and treatment times. This study also shows the activity of thalidomide and the analogs on IL-6 and IL-10 production by PBMC, with significant inhibition of IL-6 production by all compounds and treatment times and on IL-10 by compound CAT-15 after 48 hours of incubation. Our results suggest the applicability of the new compounds, CAT-15 and CAT-16, in the control of inflammatory responses since they inhibited the production of key molecules such as TNF-α, IL-6, IL-10, IL-8 and CXCL-10. Furthermore, these compounds have simplified structures, and low cost of production, are water soluble and have no chiral center. These results may contribute to the development of novel treatment strategies for certain inflammatory conditions.

Made available in DSpace on 2014-12-17T14:03:37Z (GMT). No. of bitstreams: 1 MariliaSNS_TESE.pdf: 2303324 bytes, checksum: d055f1a32ee94b3ffe5f389dbf9dffe0 (MD5) Previous issue date: 2014-04-08 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Compounds derived from fungi has been the subject of many studies in order to broaden the knowledge of their bioactive potential. Polysaccharides from Caripia montagnei have been described to possess anti-inflammatory and antioxidant properties. In this study, glucans extracted from Caripia montagnei mushroom were chemically characterized and their effects evaluated at different doses and intervals of treatment. It was also described their action on colonic injury in the model of colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS), and its action on cells of the human colon carcinoma (HT-29). Compounds extracted of C. montagnei contain high level of carbohydrates (96%), low content of phenolic compounds (1.5%) and low contamination with proteins (2.5%). The (FT-IR) and (NMR) analysis showed that polysaccharides from this species of mushroom are composed of &#945;- and &#946;-glucans. The colonic damage was evaluated by macroscopic, histological, biochemical and immunologic analyses. The results showed a reduction of colonic lesions in all groups treated with the glucans of Caripia montagnei (GCM). GCM significantly reduced the levels of IL-6 (50 and 75 mg/kg, p < 0.05), a major inflammatory cytokine. Biochemical analyses showed that such glucans acted on reducing levels of alkaline phosphatase (75 mg/kg, p < 0.01), nitric oxide (p < 0.001), and myeloperoxidase (p < 0.001). These results were confirmed microscopically by the reduction of cellular infiltration. The increase of catalase activity suggest a protective effect of GCM on colonic tissue, confirming their anti-inflammatory potential. GCM displayed cytostatic activity against HT-29 cells, causing accumulation of cells in G1 phase, blocking the cycle cell progression. Those glucans also showed ability to modulate the adhesion of HT-29 cells to Matrigel? and reduced the oxidative stress. The antiproliferative activity against HT-29 cells displayed by GCM (p <0.001) can be attributed to its cytostatic activity and induction of apoptosis by GCM / Compostos derivados de fungos tem sido alvo de muitos estudos a fim de desenvolver o conhecimento acerca de seu potencial bioativo. Polissacar?deos de Caripia montagnei j? foram descritos por possu?rem propriedades anti-inflamat?ria e antioxidante. Neste estudo, os polissacar?deos extra?dos do fungo Caripia montagnei foram caracterizados quimicamente e seus efeitos sobre as les?es intestinais foram avaliados em diferentes intervalos de tratamento no modelo de colite induzida por ?cido 2,4,6 - trinitrobenzenossulf?nico (TNBS), verificou-se ainda sua a??o sobre c?lulas do carcinoma de c?lon humano, HT-29. Na an?lise realizada no extrato obtido de C. montagnei foi verificado que este ? formado principalmente, por carboidratos (96%) apresentando um baixo teor de compostos fen?licos (1,5%) e baixa contamina??o prot?ica (2,5%). As an?lises por espectroscopia de infra vermelho (FT-IR) e resson?ncia magn?tica nuclear (RMN) mostraram que os polissacar?deos desta esp?cie de fungo s?o &#945; e &#946; -glucanas. O dano col?nico foi avaliado por an?lises macrosc?picas, histol?gicas, bioqu?micas e imunol?gicas. Os resultados mostraram a redu??o das les?es no c?lon em todos os grupos tratados com as glucanas (GCM). GCM reduziram significativamente os n?veis de IL-6 (50 e 75 mg/Kg, p < 0,05), uma importante citocina inflamat?ria. As an?lises bioqu?micas mostraram que essas glucanas atuaram na redu??o dos n?veis de fosfatase alcalina (75 mg/Kg, p < 0,01), ?xido n?trico (p < 0,001) e mieloperoxidase (p < 0,001). Estes resultados foram confirmados pela redu??o da infiltra??o celular observado microscopicamente. O aumento da atividade da catalase, sugere um efeito protetor de GCM no tecido do c?lon, o que confirma o seu potencial anti-inflamat?rio. GCM mostraram atividade citost?tica sobre as c?lulas HT-29, causando ac?mulo de c?lulas na fase G1 e impedindo, assim, a progress?o do ciclo celular. As glucanas deste estudo tamb?m mostraram habilidade em modular a ades?o de c?lulas HT-29 ao Matrigel? e reduzir o estresse oxidativo nessas c?lulas. A atividade antiproliferativa contra c?lulas HT-29 exibida por GCM pode ser atribu?da ? sua a??o citost?tica ou indu??o da apoptose por essas glucanas

We gathered normal and colorectal cancer tissues from 18 patients after tumor surgery. The tumor tissues represent caner stages from T1 to T4 (TNM system).Two-dimensional electrophoresis and MALDI-TOF techniques were utilized to identify the differentially expressed proteins. Our studies showed that there are about 18 differentially expressed proteins in normal and tumor tissues (p<0.05) which 13 proteins increased in tumor were Keratin 8, Protein disuflde isomerase A3 precursor, Keratin 18, Fractalkine precursor, LDH-B, Tropomyosin alpha 4 chain, Tropomyosin alpha 3 chain, chloride intracellular channel protein 1, PTTG1(Pituitary tumor-transforming protein 1),

Bluberries (Vaccinium sp.) are rich in polyphenols that are responsible for lowering the risk of developing several chronic degenerative diseases. However, the effect of food matrix interactions on the bioaccessibility and bioavailability of polyphenols is not well understood. In this research free and complexed polyphenols found in blueberry extracts were characterized and their antioxidant activity as well as antiproliferative activities against colon cancer cells (HT-29) and normal colon cells (CRL-1790) were evaluated. The blueberry food matrix and different carbohydrate-rich synthetic matrices were characterized and their biological activities assessed alone and in complexed state with polyphenols. The degradation of polyphenols during their transit through the gastrointestinal tract (GIT) was evaluated using an in vitro digestion model. Biological activities of blueberry polyphenols and their parent metabolites produced during colonic fermentation were estimated by in vitro antioxidant assays and cell proliferation analysis using HT-29 and CRL-1790 cell lines. HPLC analysis revealed the presence of 7 phenolic compounds and 13 anthocyanins in all samples. Although the concentration of the polyphenols varied among the samples, free and complexed polyphenols showed significant antioxidant and antiproliferative activities. Polyphenol complexes were analyzed using transmission electron microscopy (TEM) revealing the presence of electron dense complexes ranging from 100 – 200 nm. Pectinase treatment disrupted the structure of the complexes, suggesting the pectin nature of the polyphenol complexes. The antioxidant- and antiproliferative activities of the blueberry food matrix alone was below 10% compared to almost 90% and 70% of free and complexed polyphenols, respectively. Polyphenols and anthocyanins were highly stable during simulated gastric digestion step with approximately 93% and 99% of recovery, respectively. The intestinal digestion process decreased the polyphenol- and anthocyanin- contents by 49% and 15 % respectively. During colonic digestion, the complex polyphenol mixtures were degraded to a limited number of phenolic compounds. Only acetylated anthocyanins were detected in low amounts after the colonic digestion process. After simulated colonic digestion, the isolated catabolites showed lowered antioxidant activity and cell growth inhibition potential. Understanding the interactions that occur among polyphenols and different food matrices may help to produce more stable foods with better bioavailability. / The National Council of Science and Technology of Mexico (CONACYT)

Summary Natural phytochemicals are currently used in the treatment of many diseases. Cancers are just ones of them and they are ranked among the most common and the most serious. Phytochemicals in the form of cytostatics are used in chemotherapeutic treatment of cancer. In future there could be included among cytostatics also some alkaloids from the family of Amaryllidaceae, whose testing for a selective cytostatic effect on tumor cell lines of colorectal carcinoma Caco-2 and HT-29 and on normal cell lines of human intestinal epithelial FHs 74 Int is a subject of this thesis. There were tested 17 alkaloids isolated from plants of Chlidanthusfragrans, Zephyranthes robusta and Nerine bowdenii. Particularly alkaloids from plant Zephyranthes robusta namely haemanthamine with this values: IC50 = 0.99 plus/minus 0.14 microM for tumor cells, Caco-2, 0.59 plus/minus 0.01 microM for tumor cells HT-29 and 19.47 plus/minus 8.86 microM for normal cells FHs 74 Int, Lycorine with values IC50 = 0.99 plus/minus 0.08 microM for tumor cells Caco-2, 1.2 plus/minus 0.01 microM for tumor cells HT-29 and 22.68 plus/minus 0.09 microM for normal cells FHs 74 Int and Haemanthidin with values IC50 = 3.29 plus/minus 0.91 microM to tumor cells Caco-2, 1.72 plus/minus 0.11 microM to tumor cells HT-29, and 11.63 plus/minus 0.86 microM for normal cells FHs 74 Int proved a significant anti-proliferative activity. From these results there is evident the selectivity against colorectal cancer cell lines. For this reason, those tested alkaloids are suitable for further testing and for study of their biological activity against tumor cells in the terms of in vitro and in vivo.

No description available.

L’industrie libanaise du raisin et de la viniculture acquit dans les quelques années passées une renommée internationale du fait de la bonne qualité du vin produit. Il a été démontré que les constituants suspectés d’être responsable des caractéristiques biologiques du raisin sont les composés phénoliques. Ces derniers sont des métabolites secondaires des plantes, impliquées dans la protection vis-à-vis des conditions extrêmes environnementales et dans la défense contre les parasites. Ces composés contribuent aussi au goût, à l’astringence et à la couleur des produits issus du raisin. De plus, ils exhibent un pouvoir antioxydant, de ce fait un large spectre d’effets pharmacologiques leur sont attribués i.e. des propriétés anti-inflammatoire, anti-carcinogène et antiallergique. Ils peuvent aussi réduire le risque des maladies cardio-vasculaires. La production des composés phénoliques dans les fruits peut être affectée par le microclimat et les caractéristiques du terroir.En premier lieu, nous avons optimisé l’extraction des composés phénoliques totaux et des anthocyanes du raisin cultivé au Liban. Un modèle statistique basé sur la méthodologie de la surface de réponses a été utilisé pour étudier les effets de paramètres tels que le temps, la température, le choix et ratio du solvant organique dans le mélange sur la procédure d’extraction et la determination des conditions optimales. La Chromatographie Liquide à Haute Performance ou HPLC a aussi été utilisée pour suivre l’évolution de quelques composés phénoliques en fonction de la modification des paramètres d’extraction.En second lieu, afin d’étudier l’impact des composés phénoliques sur la santé humaine, l’effet de l’extrait de raisin obtenu à paritir du cépage Cabernet Sauvignon (Vitis Vinifera L. Cv. Cabernet Sauvignon) sur les cellules d’adénocarcinome colorectal – HT-29 a été déterminé.La viabilité, la prolifération, l’apoptose et le cycle cellulaire ainsi que le potentiel de membrane mitochondrial en présence de l’extrait de raisin, ont été mesurés à l’aide des techniques de microscopie, de cytométrie en flux et d’histochimie.La technologie des puces à ADN a été utilisée pour détecter des changements au niveau de l’expression des gènes dans les cellules HT-29 et pour révéler les voies de signalisation impliquées dans la réponse cellulaire aux composés phénoliques. Cette étude couvre différents aspects de la biochimie des composés phénoliques et aide à mieux comprendre leur impact sur la santé humaine, surtout au niveau cellulaire. De plus, ce projet de thèse ajoute à la valeur de l’industrie libanaise du raisin et de ses produits en proposant des conditions optimales pour extraire, analyser les composés phénoliques et montrer leurs qualités à l’échelle cellulaire. / Due to wine high quality, the Lebanese grape industry and wineries became in the past few years a business of worldwide trust. The components proved to be responsible of the grapes biological characteristics are the phenolic compounds. These are secondary plant metabolites especially implicated in plant protection against environmental extremes and defense against parasites. They as well contribute to flavor, astringency and color characteristics of grape products. Moreover, they are powerful antioxidants and exhibit a wide range of biochemical and pharmacological effects, including anti-inflammatory, anti-carcinogenic and anti-allergic properties. They can also reduce the risk of coronary heart diseases. The phenolic compounds production in fruits may be affected by microclimate and soil characteristics.Our study aimed first of all to optimize the extraction of total phenolic compounds and antocyanins from Lebanese planted grapes.Statistical experimental design based on the response surface methodology was employed to investigate the effects of parameters like time, temperature, organic solvent / water ratio on the extraction procedure, and the determination of optimum conditions.HPLC (High Performance Liquid chromatography) was also used to monitor the evolution of some phenolic compounds when modifying the extraction parameters.Second of all, to study the impact of phenolic compounds on human health, the effect of the extract obtained from Cabernet Sauvigon (Vitis vinifera L. Cv. Cabernet Sauvignon) grapes was determined on a colorectal adenocarcinoma cell line; HT-29. Cell viability/proliferation, apoptosis, cell cycle and mitochondrial membrane potential in presence of the extracts, were measured using microscopy, flow cytometry and fluorescent staining.The DNA chips technology was used to detect changes at the gene expression level of the cell line used in this study after incubation with grape extracts, and to reveal certain pathways implicated in cellular response to phenolic compounds.This study covers different aspects in the biochemistry of phenolic compounds and helps in a better comprehension of their impact on human health at the cellular level. This also provides a better value to the Lebanese grape industry and products by proposing optimal conditions to extract, monitor the phenolic compounds and by showing their roles on the cellular level

Die niedrige Inzidenz chronisch-entzündlicher Darmerkrankungen (CED) in ostasiatischen Ländern im Vergleich zu Westeuropa und den USA könnte auf unterschiedliche Lebensstile und Ernährungsgewohnheiten zurückzuführen sein. Asiaten nehmen mit der Nahrung viel höhere Mengen an Isoflavonen zu sich als Europäer und US-Amerikaner. Diese sind in der Lage, wie natürliche Östrogene an Östrogenrezeptoren (ER) zu binden. Für das Östrogen 17β-Östradiol (E2) sowie selektive Liganden des ERβ sind antiinflammatorische Wirkungen im Darm bereits nachgewiesen worden. Diese Arbeit untersuchte in Modellsystemen für CED die antiinflammatorischen Eigenschaften von Isoflavonen, speziell von Genistein, und stellte einen Vergleich mit synthetischen ER-selektiven Liganden sowie E2 her, um die Involvierung der beiden ER-Subtypen zu evaluieren. In tierexperimentellen Studien wurde der Einfluss der Testsubstanzen auf Ausprägung und Verlauf einer Kolitis in zwei Nagermodellen (HLA-B27 transgene Ratte und TNBS-induzierte Kolitis) analysiert. Ein Ernährungsexperiment, in dem eine Gruppe der Tiere bereits in utero sowie postnatal über Muttermilch und Futter hohen Phytoöstrogenspiegeln ausgesetzt war, zeigte wider Erwarten keine antiinflammatorischen Effekte auf die akute Ausprägung der induzierten Kolitis. Stattdessen waren die untersuchten Parameter bei dieser Ernährungsform gegenüber prä- und postnatal normal ernährten Tieren verstärkt. Dagegen bewirkte oral verabreichtes Genistein in der chronischen Phase der TNBS-induzierten Kolitis eine Unterdrückung der Entzündungsparameter im Darm. Die subkutane Verabreichung von Genistein, eines steroidalen ERβ-selektiven Agonisten, oder von E2 führte hingegen zu keiner signifikanten Einflussnahme auf die untersuchten Parameter in der akuten Phase der Inflammation. Zur Charakterisierung der molekularen Grundlagen einer antiinflammatorischen Wirkung von E2, synthetischen ER-selektiven Agonisten und Genistein wurden in vitro Studien mit Kolonkarzinomzelllinien (HT-29 und Caco-2) durchgeführt. Hierzu wurden die Zellen mit Interleukin-1β (IL-1β) stimuliert, was eine Induktion der inflammationsassoziierten Gene Cyclooxygenase-2 und Interleukin-6 auf mRNA Ebene bewirkte. Bis auf Genistein konnten für die getesteten Substanzen keine antiinflammatorischen Effekte auf die mRNA-Expression der induzierten Markergene beobachtet werden. Genistein bewirkte in Caco-2 Zellen eine Hemmung der untersuchten Gene. Weitere Analysen ergaben, dass die beiden Zelllinien ER nur schwach bzw. gar nicht exprimieren. Eine Transfektion von HT-29 Zellen mit ERα führte zu einer deutlichen Hemmung der Expression der Markergene durch E2, während eine Transfektion mit ERβ lediglich einen schwach hemmenden Effekt bewirkte. Die Ergebnisse der vorliegenden Arbeit legen nahe, dass die niedrigen CED-Inzidenzraten in Ostasien wohl nicht allein auf dem dortigen hohen Isoflavonkonsum beruhen, sondern auch anderen Komponenten des Lebensstils zuzuschreiben sind. Dennoch deutet sich an, dass das Genistein, bei oraler Administration, die Regeneration des geschädigten Darmgewebes im chronischen Erkrankungsverlauf unterstützen und damit auch zur Prävention von Kolonkarzinomen beitragen könnte. Bei antiinflammatorischen Effekten von ER-Liganden spielt die Transaktivierung von ER eine entscheidende Rolle. Die Wirkung von Genistein in untransfizierten Caco-2 Zellen legt jedoch auch die Teilnahme weiterer Mechanismen nahe, die noch zu untersuchen sind. Vor diesem Hintergrund erscheinen weiterführende Untersuchungen zum Einsatz von steroidalen ER-Agonisten und Genistein bei CED und den zugrunde liegenden Mechanismen als sinnvoll.