Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 123-159).

Thesis (Ph. D.)--Cornell University, May, 2007. / Vita. Includes bibliographical references (leaves 144-163).

Diss. (sammanfattning) Uppsala : Univ., 2002. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Orientador: Francisco Eduardo Martinez / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-18T07:43:37Z (GMT). No. of bitstreams: 1 Fontanelli_BeatrizAparecidaFioruci_M.pdf: 2160007 bytes, checksum: 5e358e9b41de70f7fd7c801fae0e0378 (MD5) Previous issue date: 2011 / Resumo: A exposição ao etanol altera a concentração do retinol e do all-trans-ácido retinóico (atAR) em vários tecidos. Os retinóides, retinol e atAR, são importantes para a diferenciação e manutenção das células epiteliais da próstata. O atAR se liga aos receptores de ácido retinóico (RARa, ß e y) e a interação receptor/ligante com a sequência responsiva ao retinóide no DNA, levam à transcrição de genes alvos. Assim, o atAR exerce efeitos no crescimento celular, diferenciação e apoptose, sendo essencial no desenvolvimento e diferenciação de órgãos e tecidos. Nosso objetivo foi analisar o retinol, o ácido retinóico e seus receptores, bem como, o índice de proliferação celular e de apoptose no lobo dorsolateral da próstata de ratos adultos UCh. Os animais foram divididos em quatro grupos experimentais (n=10/grupo): UChA (ingestão voluntária de etanol a 10% (v/v); UChACo (controle - ausência de etanol); UChB (ingestão voluntária de etanol a 10% (v/v) e UChBCo (controle - ausência de etanol). Após 150 dias de experimentação, os animais foram eutanasiados por decapitação e o sangue do tronco e os lobos dorsolaterais das próstatas foram coletados e processados: (1) para análises da concentração do retinol e do atAR no plasma e na próstata por meio de HPLC; (2) e análises de microscopia de luz para a proliferação celular (Ki-67), apoptose (Tunel) e para os receptores de ácido retinóico, por meio dos anticorpos anti-RARa, -ß e -y. O consumo crônico de etanol diminuiu a concentração do retinol no plasma dos grupos UChB (consumo alto de etanol) e UChA (consumo baixo de etanol). A concentração do retinol foi ainda menor no plasma do grupo UChB comparado ao UChA. No entanto, a concentração do retinol no tecido prostático não teve diferença significativa entre os grupos. O atAR aumentou significativamente somente no plasma do grupo UChB. Na próstata, a concentração do atAR aumentou no grupo UChB, enquanto que no UChA não houve diferença estatística. O RAR? na próstata dorsal e lateral dos ratos UCh não foi alterada em função do consumo de etanol. Já os RARß e -? apresentaram aumento do sinal na próstata dorsal do grupo UChB. Não houve diferença no índice de proliferação celular e de apoptose nas próstatas dorsais e laterais dos grupos experimentais. Conclui-se que o etanol altera a concentração do retinol e do atAR no plasma. Essa alteração é diretamente proporcional à quantidade de etanol consumida. Já na próstata, o retinol não é alterado pelo etanol. O consumo alto de etanol altera a concentração do atAR na próstata dorsolateral e a expressão dos RAR ß e y na próstata dorsal. A alteração da expressão dos RAR pode aumentar a sensibilidade da próstata à ação do atAR. O etanol não altera a proliferação celular e a apoptose na próstata dorsal e lateral / Abstract: Ethanol exposure alters the concentration of retinol and all-trans retinoic acid (atAR) in several tissues. Retinoids (retinol and atAR) are essential for the differentiation and homeostasis of the prostate epithelial cells. atAR binds to retinoic acid receptors (RAR a, ß and ?) and the interaction receptor/ligand with the sequence responsive to retinoid into DNA lead to transactivation of target genes. Thus, atAR directly produces their effects on cell growth, differentiation and apoptosis. This study aimed to analyze the retinol and all-trans-retinoic acid concentrations and its atAR receptors as well as the cell proliferation and apoptosis index upon the dorsolateral prostate lobe of adult UCh rats. All animals were divided into four experimental groups (n = 10/group): UChA (10% ethanol (v / v) voluntary intake); UChACo (without ethanol consumption); UChB (10% ethanol (v / v) voluntary intake) and UChBCo (without ethanol consumption). After 150 days of experimentation, animals were sacrificed followed by decapitation and trunk blood and dorsolateral prostate lobes collected. Samples of plasma and prostate by concentration analysis of the retinol and atAR were processed for HPLC. The cell proliferation and apoptosis immunoreactivities were assessed by Ki-67 and Tunel, respectively, and nuclear receptors by anti-RAR a,-ß and-y. Chronic ethanol consumption reduced the concentration of plasma retinol in UChB (high ethanol intake) and UChA groups (low ethanol intake). The retinol concentration in plasma was even lower in UChB compared to UChA group. However, the retinol concentration in prostate tissue was not significantly different between the groups. Concentration of atAR increased in plasma of UChB group, and was 96% higher in the UChA group. The prostate, atAR increased in the UChB group, while in UChA group no statistical difference. There was no statistical difference in proliferation cell and apoptosis in the dorsal and lateral prostate lobes between the groups. The expression of RAR a in the dorsal and lateral prostate of UCh rats was not altered as a function of ethanol consumption. Already RAR ß and-y showed increased signal in the dorsal prostate UChB group. We conclude that ethanol alters the concentration of retinol and atAR in plasma. This change is directly proportional to the amount of ethanol consumed. In the prostate, retinol is not altered by ethanol. The high ethanol intake alters the concentration of atAR in dorsolateral prostate and the expression of RARß and RARy in the dorsal prostate. Alteration in expression of RAR can increase sensitivity to the action of the atAR in prostate. Ethanol does not alter cell proliferation and apoptosis in the dorsolateral prostate / Mestrado / Anatomia / Mestre em Biologia Celular e Estrutural

No description available.

Retinoide sind Steroide, Derivate des Vitamin A, die ihre Wirkung durch Interaktion mit Retinoid-Rezeptoren, lokalisiert im Zellkern, entfalten. Diese Retinoid-Rezeptoren, weisen funktionelle und strukturelle Ähnlichkeiten mit dem Androgenrezeptor auf. Untersuchungen an Zellkulturen zeigen, daß der Effekt von Retinoiden auf das Zellwachstum von Prostata-Epithelzellen und Prostatakarzinomzellen keiner einfachen Kinetik folgt, sondern neben der Abhängigkeit von der Retinoid-Dosis, auch von der Zellinie, insbesondere deren Androgenrezeptor abhängt. So zeigten LNCaP-Zellen Unterschiede in der Zellproliferation im Vergleich zu PC3 oder NRP154 (Prostatakarzinom Ratte) und NRP152 (Prostataepithel Ratte). Northern-blots mit Poly(A)RNA von verschiedenen Prostata-Zellinien (benigne und maligne) nach Behandlung mit Retinoic acid (RA) bestätigte dosisabhängige Unterschiede in der Expression der Androgenrezeptor (AR)-mRNA.Umgekehrt verursachte die Behandlung mit Testosteron in verschiedenen Prostata-Zellinien (benigne und maligne) Unterschiede in der Expression der Retinoid-Rezeptor-mRNA für RAR( und RAR(. Die Ergebnisse unterstützen somit die Hypothese einer Interaktion von Retinoiden und Androgenen mit deren respektiven Rezeptoren. Untersuchungen an humanem Prostatagewebe bestätigten Unterschiede in der Expression von RAR(mRNA und RAR(mRNA mittels RT-PCR. Durch immunhistochemische Untersuchungen an humanem Prostatagewebe mit Antikörpern gegen RAR ( und RAR( konnten deren Lokalisation und Expression nachgewiesen werden. Dabei zeigte sich wiederum eine erhöhte Immunreaktivität von RAR( beim Prostatakarzinom, im Gegensatz zu RAR(, das bei benignem Prostataepithelium eine deutlich stärkere Immunreaktivität aufwies. Zusammenfassend belegen unsere Untersuchungen, daß Retinoide einen meist wachstumshemmenden Effekt auf Prostatakarzinomzellinien verursachen, der wahrscheinlich neben Bindung an Retinoid-Rezeptoren (RARs`) durch Interaktion mit dem Androgenrezeptor (AR), vermittelt durch Hemmung verschiedener membrangebundener Zellproteine und Rezeptoren, wie EGF-R verursacht wird. / Retinoids are steroids, derivatives of vitamine A, that excert their activities by interaction with the retinoic acid receptors (RARs') located in the cell nucleus. The RARs possess structural and functional similarities to the androgen receptor (AR). Investigations in cell cultures demonstrated that the effect of retinoic acid (RA) on cell proliferation is dependent not only on the RA dosage, but also on the androgen receptor status of the cell line. LNCaP cells showed a difference in cell proliferation when treated with RA, as opposed to PC3 or NRP154 (rat prostate cancer cell line) and NRP152 (rat prostate epithelial cell line). Northern blots with Poly(A)RNA from different prostate cell lines (benigne and maligne, with different androgen dependency) when treated with different concentrations of RA, demonstrated a dose-dependent expression of the androgen receptor (AR)mRNA. Conversely resulted the treatment with different concentrations of testosterone to different expressions of the RAR-mRNAs. The results, therefore, support the hypothesis of an interaction of retinoids and androgen with their respective receptors. Investigations with human prostate tissue (malignant and benign) confirms differences in RAR-expression byRT-PCR and immunhistochemistry. Again, prostate cancer showed an overexpression of RAR(, whereas benign prostate tissue demonstrated an overexpression of RAR(. Our investigations, in summary, demonstrate the overall inhibitory effect of retinoids with respect to cell proliferation in prostate cancer cell lines. There is evidence , that this biologic effect is not only triggert by interaction of retinoids and androgens with their own receptors, but occurs by cross-interaction of retinoids with the androgen receptor and androgens with the RARs. Furthermore, the biologic effect of retinoids on cell growth is dependent on membrane bound receptors, such as EGF-R.

Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 4 uppsatser.

L’acide rétinoïque (AR) est le dérivé actif majeur de la vitamine A et a de multiples rôles au niveau cellulaire ainsi que pendant le développement. L’AR agit via deux familles de récepteurs nucléaires : les Récepteurs de l’Acide Rétinoïque (RAR) et les Récepteurs X des Rétinoïdes (RXR). Ces récepteurs sont des facteurs de transcription dépendants du ligand et leur activité est régulée par des phosphorylations via des kinases activées par l’AR. Durant ma thèse, je me suis intéressé à l’étude fonctionnelle et évolutive de la voie de l’AR et de la phosphorylation des RAR chez le poisson-zèbre Danio rerio. En étudiant l’activité des différents sous-types de RAR chez le poisson-zèbre, nous avons mis en avant qu’il existe une activité transcriptionnelle propre à chaque sous-type dans un embryon précoce de poisson-zèbre. De plus, mes travaux ont montré qu’au cours de l’évolution, l’acquisition d’un site de phosphorylation chez RARα permet une régulation fine de son activité chez les mammifères. Enfin, en étudiant les mécanismes moléculaires à l’origine de la diversification de la denture chez les poissons, mes travaux mettent en avant un rôle de la voie de l’AR dans la genèse de nouveaux traits phénotypiques. / Retinoic acid (RA) is the main active metabolite of vitamin A and plays multiple roles in cellular processes but also during embryonic development. RA acts through two families of nuclear receptors: Retinoic Acid Receptors (RAR) and Retinoid X Receptors (RXR). Those receptors act as ligand-dependent transcription factors and their transcriptional activity is also regulated by phosphorylation processes through kinases activated by RA. During my PhD, I focused on the functional and evolutionary study of RA pathway and of the phosphorylation of RARs using zebrafish (Danio rerio). By studying the activity of the different RAR subtypes in zebrafish, we provide evidences that they can regulate gene expression in a subtype-specific fashion in the early zebrafish embryo. Furthermore, my work showed that during evolution, the acquisition of a phosphorylated residue in RARα promotes the fine-tuned regulation of its activity in mammals. Finally, aiming at deciphering the molecular mechanisms behind dentition diversification in fish, we propose a role for RA signaling in generating morphological novel traits during evolution.

The anatomy of the cranial peripheral nervous system has been studied for over a century, yet surprisingly little is known about how the nerves are guided to their targets. The study of the development of these nerves has important implications for our understanding of craniofacial anomalies and possible treatments for both injury and genetic disorders of nerve development such as Goldenhar-Gorlin syndrome. We have discovered that retinoic acid (RA) may play a role in the development of the trigeminal nerve. Inhibition of retinoic acid receptors (RAR) results in trigeminal nerves that become unbundled or defasciculated in the eye region. To further understand how RA is affecting trigeminal development we searched for genes downregulated in response to RAR inhibition by the inhibitor BMS-453 and have identified neurotrophin-3 (NT-3), activated leukocyte cell adhesion molecule (ALCAM) and Semaphorin 4B (Sema4B). We have analyzed the expression patterns of Sema4B and NT-3 by in situ hybridization and have found NT-3 expression in the eye and Sema4B in the embryonic target of the trigeminal nerve, lens of the eye and in the pharyngeal arches. ALCAM has been analyzed via qRT-PCR and its transcription is downregulated just prior to the observed defasciculation phenotype. The pattern of expression of these genes combined with known expression of NT-3 receptors allows us to suggest a model whereby RA signaling regulates Sema4B, ALCAM and NT-3, which support the survival, guidance and fasciculation of the trigeminal nerve. This work has the potential to better understanding of the complex nature of cranial nervous system development.