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Evaluation of the consequences of ERK and STAT3 activation in the heartBadrian, Bahareh January 2006 (has links)
[Truncated abstract] The enlargement of the heart, also known as myocardial hypertrophy, is thought to be a compensatory process that maintains the mechanical function of the heart in response to stress factors such as pressure or volume overload. Although this process is initially compensatory, it frequently results in heart failure and death. Cardiac hypertrophy is a complex process involving changes in the individual cardiac muscle cells, cardiac myocytes. As well as the morphological changes that result from hypertrophy, there are molecular changes within each cell that regulate the hypertrophic process. These molecular changes involve many different pathways within the cardiac myocytes and remain poorly understood . . . Both STAT3α and β overexpression resulted in the upregulation of the VEGF, MnSOD and SOCS-3 genes. This indicates that in the heart, STAT3β is able to activate the gene expression of these genes in a similar manner to STAT3α. However, STAT3α or β activation alone is not enough to induce cardiac hypertrophy. In conclusion, the results presented in this thesis determined a novel role for ERK in the induction of cell death in the heart and revealed many changes in cardiac gene expression following ERK activation. These genes may be the mediators of ERK responses and their identification provides valuable information and direction for further research in this area. One consequence of ERK activation was the negative regulation of the STAT3 pathway. Further investigation revealed for the first time that the STAT3 proteins themselves may not be involved in the induction of cardiac hypertrophy and that STAT3β, initially thought to be a transcriptional repressor, can induce the expression of genes that are known to be activated by STAT3α in the heart. Therefore, these results help to better understand the roles of these two signalling pathways in the heart.
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Παθοβιοχημεία της εκφύλισης μηνίσκου στον άνθρωπο : συμμετοχή του σηματοδοτικού άξονα p38 MARK-NF-kB και της Κυκλο-οξυγενάσης 2 (COX-2)Παπαδάκου, Ευγενία 24 January 2011 (has links)
Οι μηνισκικές ρήξεις διακρίνονται σε τραυματικές και εκφυλιστικές. Κλινικά δεδομένα υποδηλώνουν ότι η εκφύλιση των μηνίσκων συσχετίζεται με την οστεοαρθρίτιδα του γόνατος. Παρ’ όλα αυτά, τα μοριακά γεγονότα που καθορίζουν την παθογένεια της εκφύλισης των μηνίσκων σε ανθρώπους παραμένουν αδιευκρίνιστα.
Στη μελέτη εξετάστηκε ανοσοϊστοχημικά η έκφραση της p38 MAPKινάσης, της ενεργού φωσφορυλιομένης μορφής της p-p38, του στόχου NF-kB (με τα διμερή p50-p65) καθώς και της COX-2 σε μηνισκικές ρήξεις, και διερευνήθηκε η συμμετοχή τους στην ανάπτυξη εκφύλισης. Τα ευρήματα απέδειξαν αυξημένη έκφραση του άξονα p38-NF-kB και της COX-2 στον αποδιοργανωμένο και εκφυλισμένο ινοχόνδρινο μηνισκικό ιστό, υποδεικνύοντας ένα ρόλο των μορίων αυτών στην παθοβιοχημεία της εκφύλισης και της επακόλουθης ρήξης.
Η μελέτη είχε σκοπό να διερευνήσει και να χαρακτηρίσει την έκφραση και την ενεργοποίηση του σηματοδοτικού μονοπατιού της p38 MAPK-NF-kB και της COX-2 στα ινοχονδροκύτταρα των ανθρώπινων μηνίσκων με ρήξη. Επιπρόσθετα συσχετίσαμε τα επίπεδα έκφρασης των πρωτεϊνών αυτών με παθολογοανατομικές και κλινικές παραμέτρους, όπως η ύπαρξη εκφύλισης και η συνύπαρξη κλινικά εξακριβωμένης ΟΑ.
Χρησιμοποιήθηκαν 57 ανθρώπινοι μηνίσκοι. 43 (75,4%) άνδρες και 14 (24,6%) γυναίκες, με μέσο όρο ηλικίας 32,6 έτη, με διάρκεια πόνου 17,36 μήνες. Σε 39 ασθενείς (68,4%) η ρήξη αποδόθηκε σε τραύμα και σε 18 (31,6%) σε προϋπάρχουσα κλινικά διαγνωσμένη ΟΑ. Η ιστοπαθολογοανατομική διευκρίνιση της μηνισκικής εκφύλισης βασίστηκε σε καθιερωμένα μικροσκοπικά κριτήρια. Εκφύλιση παρατηρήθηκε σε 34 μηνίσκους (59,4%).
Χρησιμοποιήθηκαν τα αντισώματα, anti p38, anti p-p38 (μονοκλωνικά αντισώματα έναντι της ενεργοποιημένης μορφής), anti NF-kB, p50 πολυκλωνική, anti NFkBp65 πολυκλωνική και antiCOX-2.
Η ένταση της χρώσης και η αναλογία των ανοσοθετικών ινοχονδροκυττάρων εκτιμήθηκε μικροσκοπικά και βαθμολογήθηκε σε κλίμακα 0-3 (0= χωρίς ανοσοδραστικότητα, 1= ήπια, 2= μέτρια, 3= ισχυρή).
Στατιστική ανάλυση έγινε με τη δοκιμασία Mann-Whitney και η ισχύς της συσχέτισης των μεταβλητών με το Kendall’s T test, χρησιμοποιώντας το SPSS.
1.Η έκφραση της p38 ήταν στατιστικά σημαντικά υψηλότερη στους εκφυλισμένους συγκριτικά με μη εκφυλισμένους μηνίσκους. Μηνίσκοι σε ασθενείς με προϋπάρχουσα ΟΑ έδειξαν επίσης στατιστικά σημαντικά αυξημένη p38 σε σύγκριση με αυτούς με μη προϋπάρχουσα ΟΑ.
2.Η p-p38 είχε σημαντικά αυξημένη έκφραση σε εκφυλισμένους μηνίσκους έναντι μη εκφυλισμένων και σε ραγέντες μηνίσκους με ΟΑ σε σχέση με μη ΟΑ.
3.Οι υπομονάδες p50 και p65 ως τροποποιητές του άξονα p38-NFkB έδειξαν σημαντικά υψηλότερα επίπεδα στην εκφύλιση και την οστεοαρθρίτιδα.
4.Τα επίπεδα της COX-2 ήταν σημαντικά διαφορετικά μεταξύ εκφυλισμένων και μη εκφυλισμένων και σε οστεοαρθριτικές και μη αρθρώσεις, και συσχετίζονται απόλυτα με τη διακύμανση των προηγούμενων βημάτων του άξονα.
5.Η στατιστική ανάλυση αποκάλυψε σημαντική και θετική συσχέτιση μεταξύ COX-2 και p38-NF-kB και παράλληλη διακύμανσή της. / Meniscal tears are attributed to either trauma or degeneration processes. Clinical data suggest that meniscal degeneration (MD) is associated with knee osteoarthritis; however, the molecular events underpinning the pathogenesis of MD in humans remain elusive.
Here we immunohistochemically examined the expression of p38 MAPK, its phosphorylated activated form p-p38, its target NF-kB (p50-p65 dimer), and COX-2 in ruptured menisci and investigated their involvement in MD development. Our findings demonstrate increased expression of the p38-NF-kB axis elements and COX-2 in disintegrated fibrocartilage suggesting a role of these molecules in the pathobiochemistry of MD and consequential rupture.
We undertook this study to explore and characterize the expression and/or activation profile of the p38 MAPK-NF-kB signaling path away constituents and COX-2 in the fibrochondrocytes of human torn menisci. Furthermore we correlated the expression levels of the examined proteins with pathologic and clinical parameters, such as the presence of fibrocartilaginus degeneration and the coexistence of clinically identified OA.
57 human menisci were used for this study. Among the patients 43 (75,4%) were male and 14 (24,6%) female with mean age 32,6 years, with pain duration 17,36 months. In 39 patients (68,4%) meniscal tearing was attributed to trauma and in 18 (31,6%) to a background of clinically diagnosed OA. The histopathologic identification of meniscal degeneration (MD) was based on established microscopy criteria. MD was observed in 34 (59,4%) of the menisci.
The following available antibodies were employed (anti-p 38), anti p-p38 (activated form monoclonal), anti NF-kB, p50 polyclonal, anti NFkBp65 polyclonal and anti COX-2.
Strain intensity and proportion of immunopositive fibrochondrocytes was assessed by light microscopy and graded on a scale 0-3 (0= no immunoreachivity, 1= mild, 2= moderate, 3= strong).
Statistical analysis was made with Mann-Whitney tests and the strength of association between the variables by Kendall’s T test, using SPSS for Windows.
1.Expression of p-38 was significantly higher in degenerated compared with non degenerated menisci. Menisci from patients with preexisting OA showed significantly increased p38 expression levels compared to those with no preexisting OA.
2.p-p38 expression was considerably elevated in degenerated compared with non degenerated and in OA compared with non OA ruptured menisci.
3.The downstream effectors of p38 NF-kB subunits p50 and p65, exhibited significantly higher levels in degenerated and OA fibrocartilage.
4.COX-2 levels were significantly different between degenerated and non degenerated menisci, as well as between OA and non OA joints.
5.Statistical analysis revealed significant and positive correlation between COX-2 and p-38 and NF-kB.
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Influência do exercício físico no remodelamento cardíaco, estresse oxidativo e vias de sinalização das MAPK e do NF-κB de ratos espontaneamente hipertensosPagan, Luana Urbano. January 2018 (has links)
Orientador: Katashi Okoshi / Resumo: Introdução: A sobrecarga de pressão causada pela hipertensão arterial sistêmica (HAS) pode gerar mudança na arquitetura do colágeno, favorecer a fibrose, bem como o desbalanço entre a produção de espécies reativas de oxigênio (ERO) e a capacidade antioxidante. Aumento das ERO pode gerar ativação de vias sinalizadoras como a do fator nuclear kappa B (NF-kB) e das proteínas quinases ativadas por mitógenos (MAPK). Alterações dessas vias contribuem para o processo de remodelamento cardíaco causado pela HAS. O exercício físico desempenha importante papel na atenuação dos fatores de risco cardiovascular como a HAS. Dessa forma, o objetivo desse estudo foi avaliar a influência do treinamento físico sobre o remodelamento cardíaco de ratos espontaneamente hipertensos (SHR) na fase que antecede o desenvolvimento de insuficiência cardíaca. Métodos: Foram constituídos quatro grupos experimentais de ratos: normotensos Wistar (W) sedentários (W-SED, n=27); W exercitados (W-EX, n=31); SHR sedentários (SHR-SED, n=27); e SHR exercitados (SHR-EX, n=32). A partir de 13 meses de idade, os animais dos grupos exercitados foram submetidos a protocolo de exercício em esteira, cinco dias por semana, durante quatro meses. A avaliação estrutural e funcional in vivo do coração foi realizada por ecocardiograma. A função miocárdica in vitro foi avaliada em preparações de músculo papilar isolado do ventrículo esquerdo (VE). Amostras de tecido do VE foram obtidas para análises bioquímicas, histológicas e mo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: The pressure overload caused by systemic arterial hypertension (SAH) may change the collagen architecture, induce fibrosis, as well as imbalance between the reactive oxygen species (ROS) production and antioxidant capacity. Increased ROS leads to activation of signaling pathways such as nuclear factor kappa B (NF-kB) and mitogen-activated protein kinases (MAPK). Alterations in these pathways contribute to cardiac remodeling process induced by SAH. Physical exercise plays an important role in mitigating cardiovascular risk factors such as hypertension. Therefore, the aim of this study was to evaluate the influence of physical training, started before clinical evidence of heart failure, on cardiac remodeling in spontaneously hypertensive rats (SHR). Methods: Four experimental groups were used: sedentary (W-SED n=27) and trained (W-EX, n=31) normotensive Wistar rats, and sedentary (SHR-SED, n=27) and exercised (SHR-EX, n=32) hypertensive rats. Rats of the exercise groups underwent a protocol of treadmill exercise five days a week, for four months; exercise started at 13 months of age. Echocardiogram was performed to evaluate in vivo cardiac structures and function. In vitro myocardial function was analyzed in left ventricular (LV) papillary muscle preparations. LV tissue samples were obtained for biochemical, histological, and molecular analysis. Total myocardial collagen was assessed by histology and hydroxyproline quantification. Cardiomyocyte size was measured i... (Complete abstract click electronic access below) / Doutor
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Vliv chronického působení morfinu na přežití buněk po působení oxidativního stresu u neuroblastomové linie SH-SY5Y buněk / Effect of chronic morphine on cell survival after oxidative stress in the SH-SY5Y neuroblastoma cell lineMoutelíková, Karolína January 2018 (has links)
Morphine is a natural opioid which is used in medicine due to his potent analgesic and sedative effects. In the forefront of scientific interest is a chronic usage of opioids which can lead to a development of drug addiction. Morphine role in oxidative stress was described in last years. It was revealed its protective potencial by many studies. However, some studies described its pro-oxidative effect. The aim of this study was to determinate effect of chronic morphine on cell survival after oxidative stress caused by H202 analog - tBHP in the SH-SY5Y neuroblastoma cell line. The results verified morphine protective effect against oxidative stress. The highest protective effect of morphine was achieved in a concetration of 10 µM. It was desribed that morphine can induce activation of mu-opioid (MOR) and Toll-like 4 (TLR4) receptors signalling pathway on molecular level. The aim of this thesis was to evaluate the role of MOR a TLR4 in protective effect of morphine against oxidative stress by two methods. Firstly, it was used tests of oxidative stress on cell viability. The obtained results demonstrated majority role of TLR4 and minory role of MOR. Afterwards, we assesed changes in the expression of MOR a TLR4 after chronic morphine by SDS-PAGE electrophoresis. Results of these experiments did not...
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Receptores de estrogênio e vias de sinalização MAPK e P13K em hiperplasia prostática benigna e câncer de próstataSeibel, Fernanda Eugênia Rodrigues January 2014 (has links)
Em homens, com o avanço da idade ocorre declínio dos níveis plasmáticos de androgênios, enquanto os níveis de estrogênio permanecem constantes ou aumentados. Isto leva à diminuição da razão androgênio/estrogênio, sugerindo que os estrogênios podem ter um papel no desenvolvimento do câncer de próstata. Os estrogênios estão relacionados à indução da proliferação celular através da sua ligação aos receptores clássicos (ERs) e ao receptor não clássico GPER. Ambos receptores podem ativar as vias de sinalização PI3K e MAPK relacionadas à sobrevivência celular e ter importância no desenvolvimento do câncer de próstata (CaP) e da hiperplasia prostática benigna (HPB). Objetivo: Avaliar a relação dos receptores de estrogênio GPER, ERα, ERβ e suas isoformas com as vias PI3K e MAPK pela análise da expressão gênica e proteica dos receptores de estrogênio ERα, ERβ e GPER, pela análise da expressão de proteínas da via MAPK e PI3K e do estrogênio tecidual nos grupos HPB e CaP. Métodos: Tecidos prostáticos provenientes de CaP e de HPB foram submetidos à extração de RNA, o RNA foi reversamente transcrito para cDNA e avaliado usando q-PCR para a expressão dos receptores de estrogênio GPER, ERα, ERβ e suas isformas. A expressão proteica de GPER, ERα, ERβ, mTOR, PI3K e c-JUN e a ativação da p38α, ERK1/2, JNK, AKT e GSK3β foram analisadas por Western blot. A técnica de imunofluorescência foi utilizada para verificação da colocalização dos receptores GPER e ERα em estroma e epitélio de HPB e CaP. Resultados: Comparações entre os tecidos hiperplásico e de carcinoma indicaram uma maior expressão gênica e proteica de ERα e GPER em amostras de CaP comparadas à HPB. Além disso, a ativação da AKT, GSK3β e JNK e a expressão proteica da PI3K e c-JUN foram significativamente aumentadas nos tecidos de CaP enquanto que a expressão proteica de mTOR e a ativação de p38α e ERK estão diminuídas neste grupo. A expressão gênica do ERβ está aumentada no CaP porém não há diferença na expressão proteica entre os grupos. A análise da expressão gênica das isoformas do ERβ mostrou diminuição de ERβ1 e ERβ6 e aumento das isoformas ERβ2 e ERβ5 no CaP. Não foram detectadas as expressões das isoformas ERβ3 e ERβ4 em ambos os grupos. Nossos resultados também mostraram que os receptores GPER e ERα estão colocalizados no núcleo de células estromais de HPB e CaP. Além disso, o GPER está expresso com maior intensidade no epitélio de ambos os grupos enquanto o ERα está expresso com maior intensidade no estroma do CaP. A medida do estrogênio tecidual mostrou aumento deste no tecido de CaP em relação ao de HPB. Conclusões: O presente estudo mostrou aumento do estrogênio e de seus receptores ERα e GPER no CaP em relação ao HPB indicando que há modulação estrogênica na próstata. Além disso, proteínas das vias MAPK e PI3K que podem ser moduladas pela ação estrogênica estão expressas de maneiras diferentes em ambos os grupos. O estudo da ação estrogênica parece ser importante para o entendimento da progressão das doenças prostáticas. / In men with advancing age decline in plasma levels of androgens occurs while estrogen levels remain constant or increased. This leads to the decrease of the androgen / estrogen, suggesting that estrogens may play a role in the development of prostate cancer. Estrogens are related to the induction of cell proliferation by binding to classical receptors (ERs) and non-classical receptor GPER. Both receptors can activate signaling pathways PI3K and MAPK related to cell survival and have importance in the development of prostate cancer (PCa) and benign prostatic hyperplasia (BPH). Objective: To evaluate the relationship of estrogen receptors GPER, ERα, ERβ with the PI3K and MAPK pathways was performed analysis of gene and protein expression of ERα, ERβ and GPER, analysis of protein expression to MAPK and PI3K pathways and tissue estrogen in PCa and BPH groups. Methods: Prostatic tissues from PCa and BPH underwent RNA extraction, RNA was reverse transcribed to cDNA and evaluated using q-PCR for the expression of estrogen receptors GPER, ERα, ERβ and their isformas. Protein expression of GPER, ERα, ERβ, mTOR, PI3K and c-JUN and activation of p38α, ERK1/2, JNK, AKT and GSK3β were analyzed by Western blot. The immunofluorescence technique was used to verify the colocalization of GPER and ERα receptors in epithelium and stroma of BPH and PCa. Results: Comparisons between the hyperplastic tissue and carcinoma showed a higher gene and protein expression of ERα and GPER in samples of CaP compared to BPH. Furthermore, activation of AKT and GSK3β and JNK protein expression of PI3K and c-JUN were significantly increased in CaP tissues while mTOR protein expression and ERK activation p38α and are decreased in this group. ERβ gene expression is increased in PCa but there is no difference in protein expression between the groups. The analysis of gene expression of ERβ isoforms showed decreased ERβ1 and ERβ6 and increased isoforms ERβ2 and ERβ5 in CaP. Expressions were not detected isoforms and ERβ3 ERβ4 in both groups. Our results also showed that the GPER and ERα receptors are positively colocalized in nucleus of stromal cells of BPH and PCa. In addition, the GPER is expressed more intensely in the epithelium of both groups while ERα is expressed with greater intensity in the stroma of PCa. The extent of this tissue revealed increased estrogen in PCa tissue compared to BPH. Conclusions: The present study showed an increase of estrogen and its receptors ERα and GPER in CaP compared to BPH indicating that there is involvement modulation of estrogen in the prostate. Moreover, proteins of MAPK and PI3K pathways can be modulated by estrogenic activity are expressed differently in both groups. The study of estrogen action appears to be important for understanding the progression of prostatic diseases.
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Influência do exercício físico no remodelamento cardíaco, estresse oxidativo e vias de sinalização das MAPK e do NF-κB de ratos espontaneamente hipertensos / Influence of physical exercise on cardiac remodeling, oxidative stress, MAPK and NF-kB pathways signaling in spontaneously hypertensive ratsPagan, Luana Urbano 02 March 2018 (has links)
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Previous issue date: 2018-03-02 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Introdução: A sobrecarga de pressão causada pela hipertensão arterial sistêmica (HAS) pode gerar mudança na arquitetura do colágeno, favorecer a fibrose, bem como o desbalanço entre a produção de espécies reativas de oxigênio (ERO) e a capacidade antioxidante. Aumento das ERO pode gerar ativação de vias sinalizadoras como a do fator nuclear kappa B (NF-kB) e das proteínas quinases ativadas por mitógenos (MAPK). Alterações dessas vias contribuem para o processo de remodelamento cardíaco causado pela HAS. O exercício físico desempenha importante papel na atenuação dos fatores de risco cardiovascular como a HAS. Dessa forma, o objetivo desse estudo foi avaliar a influência do treinamento físico sobre o remodelamento cardíaco de ratos espontaneamente hipertensos (SHR) na fase que antecede o desenvolvimento de insuficiência cardíaca. Métodos: Foram constituídos quatro grupos experimentais de ratos: normotensos Wistar (W) sedentários (W-SED, n=27); W exercitados (W-EX, n=31); SHR sedentários (SHR-SED, n=27); e SHR exercitados (SHR-EX, n=32). A partir de 13 meses de idade, os animais dos grupos exercitados foram submetidos a protocolo de exercício em esteira, cinco dias por semana, durante quatro meses. A avaliação estrutural e funcional in vivo do coração foi realizada por ecocardiograma. A função miocárdica in vitro foi avaliada em preparações de músculo papilar isolado do ventrículo esquerdo (VE). Amostras de tecido do VE foram obtidas para análises bioquímicas, histológicas e moleculares. A avaliação do colágeno miocárdico total foi realizada pela histologia e por quantificação de hidroxiprolina. O tamanho dos miócitos foi medido em cortes histológicos do VE. A atividade das enzimas antioxidantes foi quantificada por espectrofotometria. A atividade da NADPH oxidase foi avaliada pela redução da lucigenina. A quantificação proteica dos colágenos I e III, lisil oxidase, vias MAPK e NF-kB, e inibidores teciduais 1 e 2 das metaloproteinases foi realizada por Western blot. A atividade das metaloproteinases foi realizada por zimografia. As comparações entre os grupos foram realizadas por análise de variância (ANOVA) complementada pelo teste de Bonferroni (distribuição normal), ou o teste de Kruskal-Wallis complementado pelo teste de Dunn (distribuição não normal). Resultados: A pressão arterial sistólica foi maior nos grupos SHR. Os grupos exercitados apresentaram maior capacidade física. Os sinais de insuficiência cardíaca foram maiores nos grupos hipertensos em relação aos controles, e o grupo SHR-EX apresentou menor prevalência de derrame pleural e taquipneia em comparação ao SHR-SED. O ecocardiograma mostrou reduções da espessura da parede do VE, espessura relativa do VE, diâmetro do átrio esquerdo e melhora do relaxamento no grupo SHR-EX vs. SHR-SED. O estudo da função miocárdica in vitro mostrou melhor performance no grupo SHR-EX (derivada positiva da tensão desenvolvida) vs. SHR-SED. O grupo SHR-EX mostrou maior atividade das enzimas antioxidantes em comparação SHR-SED. A produção de hidroperóxido de lipídeo, diâmetros dos miócitos, expressões proteicas da JNK fosforilada e da IkB total foram maiores nos grupos hipertensos. A quantificação de hidroxiprolina, malondialdeído, atividade da NADPH oxidase, expressões proteicas do colágeno III, lisil oxidase, TIMP-1, JNK total, p38 fosforilada, p65 fosforilada e total e IkB fosforilada não apresentaram diferença entre os grupos. A fração colágena intersticial, a atividade da MMP-2 e a expressão proteica da p38 total, ERK total e fosforilada foram maiores no SHR-SED em comparação com controle. O exercício causou redução da atividade da MMP-2 e da expressão da ERK fosforilada nos ratos hipertensos. Conclusão: O exercício físico em ratos espontaneamente hipertensos atenua o remodelamento cardíaco que está associado à melhora da tolerância ao esforço físico e redução da frequência de sinais de insuficiência cardíaca. Além disso, associa-se ao aumento da atividade das enzimas antioxidantes, diminuição da fosforilação da ERK e da atividade da MMP-2, e atenuação da expressão proteica da ERK total. / Introduction: The pressure overload caused by systemic arterial hypertension (SAH) may change the collagen architecture, induce fibrosis, as well as imbalance between the reactive oxygen species (ROS) production and antioxidant capacity. Increased ROS leads to activation of signaling pathways such as nuclear factor kappa B (NF-kB) and mitogen-activated protein kinases (MAPK). Alterations in these pathways contribute to cardiac remodeling process induced by SAH. Physical exercise plays an important role in mitigating cardiovascular risk factors such as hypertension. Therefore, the aim of this study was to evaluate the influence of physical training, started before clinical evidence of heart failure, on cardiac remodeling in spontaneously hypertensive rats (SHR). Methods: Four experimental groups were used: sedentary (W-SED n=27) and trained (W-EX, n=31) normotensive Wistar rats, and sedentary (SHR-SED, n=27) and exercised (SHR-EX, n=32) hypertensive rats. Rats of the exercise groups underwent a protocol of treadmill exercise five days a week, for four months; exercise started at 13 months of age. Echocardiogram was performed to evaluate in vivo cardiac structures and function. In vitro myocardial function was analyzed in left ventricular (LV) papillary muscle preparations. LV tissue samples were obtained for biochemical, histological, and molecular analysis. Total myocardial collagen was assessed by histology and hydroxyproline quantification. Cardiomyocyte size was measured in LV histological sections. Antioxidant enzymes activity was quantified by spectrophotometry. NADPH oxidase activity was analyzed by reduction of lucigenin. Protein expression of collagen I and III, lysyl oxidase, MAPK and NF-kB, and metalloproteinases tissue inhibitors 1 and 2 was quantified by Western blot. The activity of metalloproteinases was evaluated by zymography. Comparisons between groups were performed by two factors analysis of variance (ANOVA), complemented with the Bonferroni test (normal distribution), or Kruskal-Wallis complemented with Dunn test (non-normal distribution). Results: Systolic blood pressure was higher in the SHR groups. The exercised groups showed greater physical capacity. Prevalence of heart failure signs was higher in the hypertensive groups compared to controls, and the SHR-EX group showed lower prevalence of pleural effusion and tachypnea compared to SHR-SED. Echocardiogram showed lower LV wall thickness, LV relative wall thickness, left atrium diameter, and relaxation time in the SHR-EX group vs. SHR-SED. Myocardial functional study showed better performance in the SHR-EX group (positive derivative of the developed tension) vs. SHR-SED. The SHR-EX group showed higher antioxidant enzymes activity compared to SHR-SED. Lipid hydroperoxide production, myocyte diameters, and phosphorylated JNK and total IkB protein expression were higher in the hypertensive groups. Quantification of hydroxyproline, malondialdehyde, NADPH oxidase activity, and protein expression of collagen III, lysyl oxidase, TIMP-1, total JNK, phosphorylated p38, phosphorylated and total p65, and phosphorylated IkB did not differ between groups. The interstitial collagen fraction, MMP-2 activity, protein expression of total p38, and total and phosphorylated ERK were higher in the SHR-SED group compared to normotensive control. Physical exercise reduced the MMP-2 activity and the phosphorylated ERK expression in hypertensive rats. Conclusion: Physical exercise in spontaneously hypertensive rats attenuates cardiac remodeling associated with improved physical capacity and reduced prevalence of heart failure signs. In addition, it is associated with increased antioxidant enzymes activity, decreased ERK phosphorylation and MMP-2 activity, and attenuation of total ERK protein expression. / FAPESP: 2014/00747-1
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Receptores de estrogênio e vias de sinalização MAPK e P13K em hiperplasia prostática benigna e câncer de próstataSeibel, Fernanda Eugênia Rodrigues January 2014 (has links)
Em homens, com o avanço da idade ocorre declínio dos níveis plasmáticos de androgênios, enquanto os níveis de estrogênio permanecem constantes ou aumentados. Isto leva à diminuição da razão androgênio/estrogênio, sugerindo que os estrogênios podem ter um papel no desenvolvimento do câncer de próstata. Os estrogênios estão relacionados à indução da proliferação celular através da sua ligação aos receptores clássicos (ERs) e ao receptor não clássico GPER. Ambos receptores podem ativar as vias de sinalização PI3K e MAPK relacionadas à sobrevivência celular e ter importância no desenvolvimento do câncer de próstata (CaP) e da hiperplasia prostática benigna (HPB). Objetivo: Avaliar a relação dos receptores de estrogênio GPER, ERα, ERβ e suas isoformas com as vias PI3K e MAPK pela análise da expressão gênica e proteica dos receptores de estrogênio ERα, ERβ e GPER, pela análise da expressão de proteínas da via MAPK e PI3K e do estrogênio tecidual nos grupos HPB e CaP. Métodos: Tecidos prostáticos provenientes de CaP e de HPB foram submetidos à extração de RNA, o RNA foi reversamente transcrito para cDNA e avaliado usando q-PCR para a expressão dos receptores de estrogênio GPER, ERα, ERβ e suas isformas. A expressão proteica de GPER, ERα, ERβ, mTOR, PI3K e c-JUN e a ativação da p38α, ERK1/2, JNK, AKT e GSK3β foram analisadas por Western blot. A técnica de imunofluorescência foi utilizada para verificação da colocalização dos receptores GPER e ERα em estroma e epitélio de HPB e CaP. Resultados: Comparações entre os tecidos hiperplásico e de carcinoma indicaram uma maior expressão gênica e proteica de ERα e GPER em amostras de CaP comparadas à HPB. Além disso, a ativação da AKT, GSK3β e JNK e a expressão proteica da PI3K e c-JUN foram significativamente aumentadas nos tecidos de CaP enquanto que a expressão proteica de mTOR e a ativação de p38α e ERK estão diminuídas neste grupo. A expressão gênica do ERβ está aumentada no CaP porém não há diferença na expressão proteica entre os grupos. A análise da expressão gênica das isoformas do ERβ mostrou diminuição de ERβ1 e ERβ6 e aumento das isoformas ERβ2 e ERβ5 no CaP. Não foram detectadas as expressões das isoformas ERβ3 e ERβ4 em ambos os grupos. Nossos resultados também mostraram que os receptores GPER e ERα estão colocalizados no núcleo de células estromais de HPB e CaP. Além disso, o GPER está expresso com maior intensidade no epitélio de ambos os grupos enquanto o ERα está expresso com maior intensidade no estroma do CaP. A medida do estrogênio tecidual mostrou aumento deste no tecido de CaP em relação ao de HPB. Conclusões: O presente estudo mostrou aumento do estrogênio e de seus receptores ERα e GPER no CaP em relação ao HPB indicando que há modulação estrogênica na próstata. Além disso, proteínas das vias MAPK e PI3K que podem ser moduladas pela ação estrogênica estão expressas de maneiras diferentes em ambos os grupos. O estudo da ação estrogênica parece ser importante para o entendimento da progressão das doenças prostáticas. / In men with advancing age decline in plasma levels of androgens occurs while estrogen levels remain constant or increased. This leads to the decrease of the androgen / estrogen, suggesting that estrogens may play a role in the development of prostate cancer. Estrogens are related to the induction of cell proliferation by binding to classical receptors (ERs) and non-classical receptor GPER. Both receptors can activate signaling pathways PI3K and MAPK related to cell survival and have importance in the development of prostate cancer (PCa) and benign prostatic hyperplasia (BPH). Objective: To evaluate the relationship of estrogen receptors GPER, ERα, ERβ with the PI3K and MAPK pathways was performed analysis of gene and protein expression of ERα, ERβ and GPER, analysis of protein expression to MAPK and PI3K pathways and tissue estrogen in PCa and BPH groups. Methods: Prostatic tissues from PCa and BPH underwent RNA extraction, RNA was reverse transcribed to cDNA and evaluated using q-PCR for the expression of estrogen receptors GPER, ERα, ERβ and their isformas. Protein expression of GPER, ERα, ERβ, mTOR, PI3K and c-JUN and activation of p38α, ERK1/2, JNK, AKT and GSK3β were analyzed by Western blot. The immunofluorescence technique was used to verify the colocalization of GPER and ERα receptors in epithelium and stroma of BPH and PCa. Results: Comparisons between the hyperplastic tissue and carcinoma showed a higher gene and protein expression of ERα and GPER in samples of CaP compared to BPH. Furthermore, activation of AKT and GSK3β and JNK protein expression of PI3K and c-JUN were significantly increased in CaP tissues while mTOR protein expression and ERK activation p38α and are decreased in this group. ERβ gene expression is increased in PCa but there is no difference in protein expression between the groups. The analysis of gene expression of ERβ isoforms showed decreased ERβ1 and ERβ6 and increased isoforms ERβ2 and ERβ5 in CaP. Expressions were not detected isoforms and ERβ3 ERβ4 in both groups. Our results also showed that the GPER and ERα receptors are positively colocalized in nucleus of stromal cells of BPH and PCa. In addition, the GPER is expressed more intensely in the epithelium of both groups while ERα is expressed with greater intensity in the stroma of PCa. The extent of this tissue revealed increased estrogen in PCa tissue compared to BPH. Conclusions: The present study showed an increase of estrogen and its receptors ERα and GPER in CaP compared to BPH indicating that there is involvement modulation of estrogen in the prostate. Moreover, proteins of MAPK and PI3K pathways can be modulated by estrogenic activity are expressed differently in both groups. The study of estrogen action appears to be important for understanding the progression of prostatic diseases.
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Receptores de estrogênio e vias de sinalização MAPK e P13K em hiperplasia prostática benigna e câncer de próstataSeibel, Fernanda Eugênia Rodrigues January 2014 (has links)
Em homens, com o avanço da idade ocorre declínio dos níveis plasmáticos de androgênios, enquanto os níveis de estrogênio permanecem constantes ou aumentados. Isto leva à diminuição da razão androgênio/estrogênio, sugerindo que os estrogênios podem ter um papel no desenvolvimento do câncer de próstata. Os estrogênios estão relacionados à indução da proliferação celular através da sua ligação aos receptores clássicos (ERs) e ao receptor não clássico GPER. Ambos receptores podem ativar as vias de sinalização PI3K e MAPK relacionadas à sobrevivência celular e ter importância no desenvolvimento do câncer de próstata (CaP) e da hiperplasia prostática benigna (HPB). Objetivo: Avaliar a relação dos receptores de estrogênio GPER, ERα, ERβ e suas isoformas com as vias PI3K e MAPK pela análise da expressão gênica e proteica dos receptores de estrogênio ERα, ERβ e GPER, pela análise da expressão de proteínas da via MAPK e PI3K e do estrogênio tecidual nos grupos HPB e CaP. Métodos: Tecidos prostáticos provenientes de CaP e de HPB foram submetidos à extração de RNA, o RNA foi reversamente transcrito para cDNA e avaliado usando q-PCR para a expressão dos receptores de estrogênio GPER, ERα, ERβ e suas isformas. A expressão proteica de GPER, ERα, ERβ, mTOR, PI3K e c-JUN e a ativação da p38α, ERK1/2, JNK, AKT e GSK3β foram analisadas por Western blot. A técnica de imunofluorescência foi utilizada para verificação da colocalização dos receptores GPER e ERα em estroma e epitélio de HPB e CaP. Resultados: Comparações entre os tecidos hiperplásico e de carcinoma indicaram uma maior expressão gênica e proteica de ERα e GPER em amostras de CaP comparadas à HPB. Além disso, a ativação da AKT, GSK3β e JNK e a expressão proteica da PI3K e c-JUN foram significativamente aumentadas nos tecidos de CaP enquanto que a expressão proteica de mTOR e a ativação de p38α e ERK estão diminuídas neste grupo. A expressão gênica do ERβ está aumentada no CaP porém não há diferença na expressão proteica entre os grupos. A análise da expressão gênica das isoformas do ERβ mostrou diminuição de ERβ1 e ERβ6 e aumento das isoformas ERβ2 e ERβ5 no CaP. Não foram detectadas as expressões das isoformas ERβ3 e ERβ4 em ambos os grupos. Nossos resultados também mostraram que os receptores GPER e ERα estão colocalizados no núcleo de células estromais de HPB e CaP. Além disso, o GPER está expresso com maior intensidade no epitélio de ambos os grupos enquanto o ERα está expresso com maior intensidade no estroma do CaP. A medida do estrogênio tecidual mostrou aumento deste no tecido de CaP em relação ao de HPB. Conclusões: O presente estudo mostrou aumento do estrogênio e de seus receptores ERα e GPER no CaP em relação ao HPB indicando que há modulação estrogênica na próstata. Além disso, proteínas das vias MAPK e PI3K que podem ser moduladas pela ação estrogênica estão expressas de maneiras diferentes em ambos os grupos. O estudo da ação estrogênica parece ser importante para o entendimento da progressão das doenças prostáticas. / In men with advancing age decline in plasma levels of androgens occurs while estrogen levels remain constant or increased. This leads to the decrease of the androgen / estrogen, suggesting that estrogens may play a role in the development of prostate cancer. Estrogens are related to the induction of cell proliferation by binding to classical receptors (ERs) and non-classical receptor GPER. Both receptors can activate signaling pathways PI3K and MAPK related to cell survival and have importance in the development of prostate cancer (PCa) and benign prostatic hyperplasia (BPH). Objective: To evaluate the relationship of estrogen receptors GPER, ERα, ERβ with the PI3K and MAPK pathways was performed analysis of gene and protein expression of ERα, ERβ and GPER, analysis of protein expression to MAPK and PI3K pathways and tissue estrogen in PCa and BPH groups. Methods: Prostatic tissues from PCa and BPH underwent RNA extraction, RNA was reverse transcribed to cDNA and evaluated using q-PCR for the expression of estrogen receptors GPER, ERα, ERβ and their isformas. Protein expression of GPER, ERα, ERβ, mTOR, PI3K and c-JUN and activation of p38α, ERK1/2, JNK, AKT and GSK3β were analyzed by Western blot. The immunofluorescence technique was used to verify the colocalization of GPER and ERα receptors in epithelium and stroma of BPH and PCa. Results: Comparisons between the hyperplastic tissue and carcinoma showed a higher gene and protein expression of ERα and GPER in samples of CaP compared to BPH. Furthermore, activation of AKT and GSK3β and JNK protein expression of PI3K and c-JUN were significantly increased in CaP tissues while mTOR protein expression and ERK activation p38α and are decreased in this group. ERβ gene expression is increased in PCa but there is no difference in protein expression between the groups. The analysis of gene expression of ERβ isoforms showed decreased ERβ1 and ERβ6 and increased isoforms ERβ2 and ERβ5 in CaP. Expressions were not detected isoforms and ERβ3 ERβ4 in both groups. Our results also showed that the GPER and ERα receptors are positively colocalized in nucleus of stromal cells of BPH and PCa. In addition, the GPER is expressed more intensely in the epithelium of both groups while ERα is expressed with greater intensity in the stroma of PCa. The extent of this tissue revealed increased estrogen in PCa tissue compared to BPH. Conclusions: The present study showed an increase of estrogen and its receptors ERα and GPER in CaP compared to BPH indicating that there is involvement modulation of estrogen in the prostate. Moreover, proteins of MAPK and PI3K pathways can be modulated by estrogenic activity are expressed differently in both groups. The study of estrogen action appears to be important for understanding the progression of prostatic diseases.
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Participação de proteínas tirosina quinase ativada por mitógenos (MAPKs) na indução do fator inibidor de leucemia (LIF) em células estromais da medula óssea de crianças com sindromes mielodisplásicas (SMD) / Participation of protein tyrosine kinase activated by mitógenos (MAPKs) in the induction of the inhibitory factor for leukemia (LIF) stromal cells in the bone marrow of children with Myelodysplastic Syndromes (MDS)Simone Vieira da Costa 22 September 2008 (has links)
Em nosso trabalho anterior mostramos que dentre as citocinas analisadas, os níveis do mRNA de LIF nas células estromais pediátricas, de SMD e de SMD-LMA foram maiores quando comparados às células estromais de crianças saudáveis. No presente estudo, observamos um aumento tempo dependente nos níveis da proteína LIF após adição de SFB em todas as células analisadas (células estromais de crianças saudáveis, de SMD e de SMD-LMA). O envolvimento de p38, ERK e JNK na expressão LIF nestas células foi determinado pelo uso de inibidores dos membros das proteínas quinase ativadas por mitógenos: ERK (PD98059), p38 (SB302580) e JNK (SP600125) os quais inibiram a produção de LIF nas células estromais de crianças saudáveis, após estas serem estimuladas por SFB. No entanto, os níveis da expressão de LIF-induzido por soro nas células estromais de SMD e de SMD-LMA tratadas com SB302580 (p38) foram significativamente diminuídos, em comparação com a inibição observada no tratamento com PD98059 e SP600125 (p <0001, teste ANOVA). Em adição analisamos as formas fosforiladas de p38 e ERK, após 48hs na ausência ou na presença de soro por diferentes tempos. Níveis de atividade de ERK e do p38 foram inicialmente elevados na ausência de soro. A atividade de p38 foi sustentada após tratamento com SFB, entretanto, ERK apresentou uma variação de atividade durante o tratamento. Sugerimos que a sinalização das MAPKs (p38, ERK e JNK), em resposta a fatores de crescimento presentes no soro, parece desempenhar um papel importante na expressão da LIF em células estromais de crianças saudáveis, mas a sinalização do p38 parece ser funcionalmente mais importante nas mielodisplasias ou naquelas associadas à LMA / Our previous report showed that among the cytokines analysed, LIF mRNA levels in stromal cells from pediatric MDS and MDS-AML were higher as compared to those found in healthy stromal cells. In the present study, we have observed an increased protein LIF levels in a time dependent manner after FCS stimulation in all stromal cells analysed (MDS, MDS-AML and healthy children) and the involvement of p38, ERK and JNK pathways in the LIF expression in these cells was determined. In stromal cells from two healthy children, LIF production was equally inhibited in a dose dependent manner after FCS stimulation by mitogen-activated protein kinase (MAPKs) members inhibitors: ERK (PD98059), p38 (SB302580) and JNK (SP600125). However, in MDS and MDS-AML stromal cells, the levels of LIF-induced by serum, were significantly decreased by SB302580, as compared with the inhibition observed by treatment with PD98059 and SP600125 (p <0,001, ANOVA test). In addition we have analysed the presence of p38 and ERK phosphorylated forms in stromal cells, after 48hs of serum starvation or in the presence of FCS for different times. Activated ERK and p38MAPK levels were initially elevated in the absence of serum. p38MAPK activation was sustained after treatment with FCS, whereas ERK presented a variation of the activated forms during treatment. We suggest that the signalling of the MAPKs (p38, ERK and JNK) in response to growth factors present in the serum, seems to play an important role in the LIF expression by stromal cells of healthy children, but p38 MAPK signalling appears to be functionally more important in MDS and MDS-AML
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SCF-mediated degradation of the two translational regulators, CPB-3 and GLD-1, during oogenesis in C. elegansKisielnicka, Edyta 17 April 2018 (has links) (PDF)
The development of an organism and its adult homeostasis rely on regulatory mechanisms that control the underlying gene expression programs. In certain biological contexts, such as germ cell development, gene expression regulation is largely executed at the post-‐transcriptional level. This relies on RNA-‐binding proteins (RBPs), whose activity and expression are also heavily controlled. While the RNA-‐binding potential of RBPs is currently of intense scrutiny, surprisingly little is known to date about the molecular mechanisms that control RNA-‐binding proteins abundance in the context of germ cell development.
This work identifies the molecular mechanisms that shape expression patterns of two evolutionarily conserved RNA-‐binding proteins, CPB-‐3 and GLD-‐ 1, which belong to CPEB and STAR protein family, respectively. By focusing on their regulation in the C. elegans germ line, this work reveals an involvement of the proteasome in reducing levels of CPB-‐3/CPEB and GLD-‐1/STAR at the pachytene-‐to-‐diplotene transition during meiotic prophase I. Furthermore, it documents that CPB-‐3 and GLD-‐1 are targeted to proteasomal degradation by a conserved SCF ubiquitin ligase complex that utilises SEL-‐10/Fbxw7 as a substrate recognition subunit. Importantly, destabilisation of both RBPs is likely triggered by their phosphorylation, which is regulated by the mitogen-‐activated protein kinase, MPK-‐1, and restricted to the meiotic timepoint of pachytene exit. Lastly, this work investigates the potential consequences of target mRNA regulation upon delayed RBP degradation. Altogether, the collected data characterise a molecular pathway of CPEB and STAR protein turnover, and suggest that MPK-‐1 signaling may couple RBP-‐mediated regulation of gene expression to progression through meiosis during oogenesis.
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