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Tracing the architecture of caffeic acid phenethyl ester cocrystals: studies on crystal structure, solubility, and bioavailability implicationsKetkar, S.S., Pagire, Sudhir K., Goud, N.R., Mahadik, K.R., Nangia, A., Paradkar, Anant R 2016 August 1919 (has links)
Yes / Caffeic acid phenethyl ester (CAPE) is a polyphenolic active compound present in popular apiproduct, ‘propolis’ obtained from beehives. Though it has broad therapeutic capability, the bioavailability of CAPE is limited due to poor solubility. In this study, we report novel cocrystals of CAPE engineered using coformers such as caffeine (CAF), isonicotinamide (INIC), nicotinamide (NIC) with enhanced solubility and bioavailability of CAPE. The cocrystals were prepared by microwave-assisted cocrystallization and characterized using PXRD, DSC and Raman spectroscopy. PXRD and DSC confirm the successful formation and phase purity of CAPE-CAF, CAPE-INIC and CAPE-NIC cocrystals. Raman spectra of CAPE cocrystals complement these results in confirming the formation of novel crystalline phases. CAPE-NIC cocrystal was further subjected to X-ray crystallography to understand its molecular arrangement and hydrogen bonding in the crystal structure. The CAPE-NIC cocrystal structure is found to be stabilized by a rare 1,2-benzenediol-amide heterosynthon. Cocrystallization of CAPE with NIC improved its aqueous solubility and pharmacokinetic profile thereby demonstrating 2.76 folds escalation in bioavailability. / We thank UKIERI: UK-India Education and Research Initiative (TPR26) and EPSRC (EP/J003360/1, EP/L027011/1) for providing financial support during this study.
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Pharmacokinetics and cytoprotective evaluation of Caffeic Acid Phenethyl Amide and fluorinated derivatives against oxidative stressYang, John 26 February 2013 (has links)
Ischemic injury occurs when the flow of blood is reduced or blocked to an area of the body and can cause significant tissue damage by generation of reactive oxygen species (ROS), activation of apoptotic pathways and through induction of the inflammatory response. Restoration of blood flow and reperfusion of the blocked site, while essential, can generate a second injury that itself needs to be controlled. Together the two injuries are termed ischemia/reperfusion (I/R) injury. This type of injury is frequently encountered in medicine and is a major medical problem. Therapeutic strategies to combat I/R injury include the introduction of compounds that can scavenge ROS or can induce metabolic pathways with the effect of inhibiting apoptosis. Caffeic Acid Phenethyl Ester (CAPE), a polyphenolic compound found in propolis, has been shown to protect a variety of cells types against ROS in vitro and has also been shown to induce a variety of genes including hemeoxygenase 1 (HMOX-1) , an enzyme that has been implicated in a cytoprotective pathway. Despite showing significant cytoprotection of cells against oxidant stress in vitro, CAPE is readily hydrolyzed in plasma and is also quickly removed from circulation. This result may explain the limited cytoprotective effects of CAPE in vivo. We have synthesized a series of CAPE amide derivatives, including Caffeic Acid Phenethyl Amide (CAPA), with the aim of improving CAPE’s stability properties while maintaining the cytoprotective effects of the parent compound. We found that CAPA, in addition to 2 other amide derivatives, were able to protect human umbilical vein endothelial cells (HUVEC) against ROS to a similar degree as CAPE. In addition, we have observed significant improvement in plasma stability of CAPA over CAPE at multiple temperatures. The elimination half-life of CAPA from the systemic circulation was also seen to be significantly improved over CAPE following intravenous administration to male Sprague-Dawley rats. The longer residence time of CAPA over CAPE in circulation may potentially result in greater cytoprotection in vivo. / text
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Kavos rūgšties fenetilo esterio poveikio inkstų mitochondrijoms tyrimas / The effect of caffeic acid phenethyl ester on kidney mitochondriaBaranauskaitė, Agnė 18 June 2014 (has links)
Tyrimo tikslas: ištirti kavos rūgšties fenetilo esterio (CAFE) poveikį išemijos paveiktų žiurkės inkstų mitochondrijų funkcijoms.
Uždaviniai: įvertinti tiesioginį in vitro CAFE poveikį inkstų mitochondrijų funkcijoms; CAFE poveikį išemijos (20 min) in vitro paveiktų inkstų mitochondrijų funkcijoms; kvėpavimo grandinės I komplekso aktyvumui; mitochondrijų gebėjimui kaupti Ca2+.
Metodai. Wistar veislės žiurkių patinėliai buvo skirstomi į 4 grupes: kontrolinė grupė, 20 min trukmės išemijos, CAFE 22 mg/kg ir CAFE 34 mg/kg. CAFE buvo leidžiamas 1,5 h prieš sukeliant išemiją. Mitochondrijos buvo išskiriamos diferencinio centrifugavimo būdu. Mitochondrijų kvėpavimo greitis mitochondrijoms oksiduojant I ir II komplekso substratus buvo registruojamas poliarografiškai Klarko tipo elektrodu. Ca2+ sugėrimas buvo matuojamas fluorimetriškai. Mitochondrijų kvėpavimo grandinės I komplekso aktyvumas buvo tiriamas spektrofotometriškai.
Rezultatai: CAFE (0,7 – 4,5 M) didina mitochondrijų kvėpavimo greitį 2-oje metabolinėje būsenoje nuo 15 % iki 34 % ir neveikė mitochondrijų kvėpavimo greičio 3-ioje metabolinėje būsenoje (VADP). Didesnės koncentracijos (5,2 - 6,5 µM) slopina mitochondrijų kvėpavimo greitį VADP (16 % ir 43 % atitinkamai). Tiriant CAFE poveikį 20 min išemijos in vitro paveiktų mitochondrijų funkcijoms, nustatyta, jog 22 mg/kg ir 34 mg/kg CAFE, intraperitonealinė injekcija 1,5 h prieš sukeliant inkstų išemiją, 20 % (p<0,05) pagerino mitochondrijų kvėpavimo greitį VADP bei... [toliau žr. visą tekstą] / The aim of investigation: to analyse the effect of caffeic acid phenethyl ester (CAPE) on kidney mitochodrial functions.
Objectives: to evaluate direct in vitro effect of CAPE on kidney mitochondrial functions; the impact of CAPE on ischemia (20 min) in vitro affected kidney mitochondrial functions; on the mitochondrial respiratory chain complex I activity and on the mitochondria capability to accumulate Ca2+.
Methods. Wistar rats were pretreated intraperitoneal with 22 mg/kg and 34 mg/kg of CAPE. Animals were divided into 4 groups: control group, 20 min of ischemia, CAPE 22 mg/kg group and CAPE 34 mg/kg group. Mitochondria were isolated by means of differential centrifugation. The mitochondrial respiration rate while oxidizing complex I and II dependent substrates was registered polarographically with Clark-type electrode. Ca2+ accumulation was measured fluorometrically. Activity of complex I was measured spectrophotometrically.
Results: the results shown that CAPE 0,7 - 4,5 µM increases mitochondrial State 2 respiration rate by 15 - 34 % and has no effect on the State 3 respiration rate. Higher concentrations (5,2 - 6,5 µM) decreased mitochondrial State 3 respiration rate by 16% and 43%, respectively. Pretreatment with CAPE (22 mg/kg and 34 mg/kg) increased (by 20%) the ischemia suppressed mitochondrial State 3 respiration rate and respiratory control index. CAPE had no effect on succinate oxydation. Pretreatment with CAPE (22 mg/kg and 34 mg/kg) increased Ca2+... [to full text]
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Estudo da relação entre estrutura química e atividade biológica de inibidores de NADPH Oxidase em leucócitos: relevância da oxidabilidade e hidrofobicidade / Study of Relationship Between Chemical Structure and Biological Activity of NADPH Oxidase Inhibitors in Leukocyte: relevance of Oxidisability and hydrophobicityParacatu, Luana Chiquetto [UNESP] 17 June 2016 (has links)
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Previous issue date: 2016-06-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Inúmeras patologias têm a sua gênese e/ou progressão relacionadas à produção desregulada de intermediários oxidantes. O complexo multienzimático NADPH oxidase é um dos componentes de maior relevância neste contexto, pois é uma das principais fontes de ânion superóxido no organismo animal. Sendo expresso em inúmeros tecidos, incluindo leucócitos e células do tecido endotelial, o desenvolvimento de inibidores eficientes deste complexo enzimático poderá significar uma nova terapêutica para o tratamento de doenças inflamatórias crônicas. Com objetivo de explorar a relação entre a estrutura molecular, as propriedades químicas e atividades biológicas, utilizamos o éster fenetílico do ácido cafeico (CAPE) como inibidor do complexo enzimático NADPH oxidase e comparamos sua eficácia com o seu precursor ácido cafeico e os derivados, éster fenetílico do ácido cinâmico e o ácido clorogênico, correlacionando-os a respeito a sua hidrofobicidade, propriedades redox e inibição do complexo NADPH oxidase em leucócitos ativados. A hipótese seria de que um aumento da hidrofobicidade provocado pela esterificação do ácido cafeico poderia facilitar o seu acesso à membrana celular e assim alterar seu efeito como possível inibidor de NADPH Oxidase. Os resultados, em ensaios in vitro, mostraram que as alterações na hidrofobicidade não provocaram alterações significativas no potencial de oxidação e potencial antioxidantes dos compostos testados. Quando testados em leucócitos ativados (modelos ex vivo), a esterificação provocou uma melhora significativa na capacidade de inibição do complexo NADPH oxidase. Este potente efeito se propagou às EROs decorrentes de ânion superóxido e produzidas por leucócitos, como peróxido de hidrogênio e ácido hipocloroso, entretanto, sem alterar a capacidade fagocítica dos leucócitos. Os resultados deste estudo mostram que nos ensaios celulares o CAPE foi o composto mais potente em relação ao seu precursor ácido e ácido clorogênico, sendo significativamente mais efetivo na inibição da produção das EROs. Da mesma forma, CAPE foi o inibidor mais eficaz da expressão de TNF-α e IL-10 por Staphylococcus aureus células estimuladas. Em conclusão, a presença do grupo catecol e a maior hidrofobicidade, do CAPE, foram essenciais para os efeitos biológicos, confirmando nossa hipótese. Considerando-se o envolvimento da NADPH-oxidases na génese e progressão de doenças inflamatórias, CAPE deve ser considerada como uma droga anti-inflamatória promissora. / Several diseases have their genesis and / or progression related to unregulated production of oxidants intermediates. The multienzymatic complex NADPH oxidase is one of the most important components in this context because it is a major source of superoxide anion in animal organisms. It is expressed in numerous tissues, including leukocytes and endothelial tissue cells. Developing effective inhibitors of this enzyme complex may indicate a new therapy for the treatment of chronic inflammatory diseases. Several studies have described numerous anti-inflammatory properties attributed to caffeic acid phenethyl ester (CAPE), an active component found in propolis. In order to explore the relationship between the molecular structure, chemical properties and biological activities, we used CAPE to inhibit the enzyme complex NADPH oxidase and compare its efficacy with the its precursor caffeic acid and derivatives, phenethyl ester of cinnamic acid and chlorogenic acid, correlating them with regard to hydrophobicity, redox properties and inhibition of NADPH oxidase complex on activated leukocytes. The hypothesis was that an increase of hydrophobicity caused by the esterification of caffeic acid could facilitate access to cell membranes and thereby alter its effect as a possible inhibitor of NADPH oxidase. The results (in vitro), showed that the changes in hydrophobicity did not provoke significant changes in the oxidation potential and antiradical potency of the tested compounds. But when tested in activated leukocytes (ex vivo), the esterification caused a significant improvement in the ability to inhibit the NADPH oxidase complex. This potent inhibition effect resulted also in the blockage of production of hypochlorous acid, however, without altering the phagocytic ability of leukocytes. The results of this study show that in cellular assays, CAPE was the most potent compound in comparison to caffeic acid and chlorogenic acid, significantly more effective in inhibiting the production of ROS. Likewise, CAPE was the most effective inhibitor of expression of TNF-α and IL-10 in Staphylococcus aureus stimulated cells. In conclusion, the presence of the catechol moiety and the higher hydrophobicity of CAPE were essential for the biological effects. Considering the involvement of NADPH oxidases in the genesis and progression of inflammatory diseases, CAPE should be considered as a promising anti-inflammatory drug.
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Produção de biblioteca de compostos derivados de produtos naturais: síntese e estudo de atividades biológicas / Production of library of compounds derived from natural products: synthesis and study of biological activitiesMello, Rodrigo Brito de 19 September 2014 (has links)
O presente trabalho trata da semissíntese de análogos de importantes compostos líderes (afidicolina, lausona, lapachol e CAPE) utilizando técnicas de química medicinal como bioisosterismo, adição de grupamento funcional e simplificação molecular. Dessa forma foi possível obter uma biblioteca de análogos racionais, visando a manipulação de parâmetros físico-químicos e estruturais, para fins de bioprospecção. Foram desenvolvidos derivados de afidicolina mais lipofílicos, por meio da acilação das hidroxilas presentes na estrutura química deste terpeno. Tentativas de formação de bioisósteros, sais e de ésteres fosfato das hidroxinaftoquinonas naturais - lapachol e lausona, foram realizadas visando avaliar a influência do pKa sobre a atividade deste tipo de moléculas, bem como aumentar hidrossolubilidade. Neste caso, foram observadas reações paralelas, como um rearranjo molecular para a formação de aminonaftoquinonas, no estudo da cicloadição de azida de sódio com grupos cianos. Ademais, foi estudado o efeito da simplificação molecular de CAPE (fenetil éster do ácido cafeico), visando entender os requisitos estruturais de atividade antitumoral desta classe de compostos. Neste trabalho, foram obtidas 14 moléculas e testadas para diferentes atividades biológicas. Derivados naftoquinoidais se mostraram ativos frente à inibição de DHODH em ensaio sobre a enzima e também em ensaio celular. Adicionalmente, análogos simplificados do CAPE apresentaram alta atividade antitumoral, com segurança, em comparação ao controle 5-fluorouracila. / The present study aimed the semi-synthesis of analogues from important lead compounds (aphidicolin, lausone, lapachol and CAPE) by using medicinal chemistry strategies, such as bioisosterism, addition of functional groups and molecular simplification. Thus, we obtained a library of rational analogues, aiming the manipulation of physicochemical and structural parameters with bioprospecting purposes. We developed more lipophilic aphidicolin derivatives by acylation of the hydroxyl groups present in the structure of this terpene. Attempts towards the development of phosphate salts bioisosters from the hydroxinaftoquinones lapachol and lausone in order to evaluate the influence the pKa in the biological activity of these class compounds as well as to increase the water solubility. In this last case, we observed parallel reactions, as a molecular rearrangement for the formation of the aminonaftoquinones during the study of cycloaddition with cyanides and azides. In addition, we studied the effects of molecular simplification of CAPE (caffeic acid phenethyl ester), to better understand the structural requirements for antitumoral activity of this class of compounds. In the present work we obtained 14 molecules which were also tested for different biological activities. Naftoquinoidais derivatives showed inhibition activity on enzymatic essay on DHODH and on cellular essay. Moreover, simplified molecules from CAPE showed high antitumoral activity and safety in comparison to the control 5- fluorouracil.
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Produção de biblioteca de compostos derivados de produtos naturais: síntese e estudo de atividades biológicas / Production of library of compounds derived from natural products: synthesis and study of biological activitiesRodrigo Brito de Mello 19 September 2014 (has links)
O presente trabalho trata da semissíntese de análogos de importantes compostos líderes (afidicolina, lausona, lapachol e CAPE) utilizando técnicas de química medicinal como bioisosterismo, adição de grupamento funcional e simplificação molecular. Dessa forma foi possível obter uma biblioteca de análogos racionais, visando a manipulação de parâmetros físico-químicos e estruturais, para fins de bioprospecção. Foram desenvolvidos derivados de afidicolina mais lipofílicos, por meio da acilação das hidroxilas presentes na estrutura química deste terpeno. Tentativas de formação de bioisósteros, sais e de ésteres fosfato das hidroxinaftoquinonas naturais - lapachol e lausona, foram realizadas visando avaliar a influência do pKa sobre a atividade deste tipo de moléculas, bem como aumentar hidrossolubilidade. Neste caso, foram observadas reações paralelas, como um rearranjo molecular para a formação de aminonaftoquinonas, no estudo da cicloadição de azida de sódio com grupos cianos. Ademais, foi estudado o efeito da simplificação molecular de CAPE (fenetil éster do ácido cafeico), visando entender os requisitos estruturais de atividade antitumoral desta classe de compostos. Neste trabalho, foram obtidas 14 moléculas e testadas para diferentes atividades biológicas. Derivados naftoquinoidais se mostraram ativos frente à inibição de DHODH em ensaio sobre a enzima e também em ensaio celular. Adicionalmente, análogos simplificados do CAPE apresentaram alta atividade antitumoral, com segurança, em comparação ao controle 5-fluorouracila. / The present study aimed the semi-synthesis of analogues from important lead compounds (aphidicolin, lausone, lapachol and CAPE) by using medicinal chemistry strategies, such as bioisosterism, addition of functional groups and molecular simplification. Thus, we obtained a library of rational analogues, aiming the manipulation of physicochemical and structural parameters with bioprospecting purposes. We developed more lipophilic aphidicolin derivatives by acylation of the hydroxyl groups present in the structure of this terpene. Attempts towards the development of phosphate salts bioisosters from the hydroxinaftoquinones lapachol and lausone in order to evaluate the influence the pKa in the biological activity of these class compounds as well as to increase the water solubility. In this last case, we observed parallel reactions, as a molecular rearrangement for the formation of the aminonaftoquinones during the study of cycloaddition with cyanides and azides. In addition, we studied the effects of molecular simplification of CAPE (caffeic acid phenethyl ester), to better understand the structural requirements for antitumoral activity of this class of compounds. In the present work we obtained 14 molecules which were also tested for different biological activities. Naftoquinoidais derivatives showed inhibition activity on enzymatic essay on DHODH and on cellular essay. Moreover, simplified molecules from CAPE showed high antitumoral activity and safety in comparison to the control 5- fluorouracil.
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Efeitos dos inibidores de NF Kappa-B e Rho Quinase em um modelo de asma animal: comparação com o tratamento com corticosteroides / Effects of NFkB and rho-quinase inhibitors in an animal asthma model: comparison to corticosteroid treatmentSouza, Flávia Castro Ribas de 15 December 2017 (has links)
Embora a grande maioria dos pacientes com asma tenha controle com o padrão de tratamento com corticosteroides, 5 a 10% destes asmáticos ainda desenvolvem algumas formas graves da doença e são considerados pacientes difíceis de controlar. A ativação do NFkB contribui para a manutenção e desenvolvimento de inflamação pulmonar crônica na fisiopatologia da asma. O éster fenetilico do ácido cafeico (CAPE), um componente ativo de própolis das colmeias de abelhas, é conhecido por ter propriedades antiinflamatórias e imunomoduladoras. É conhecido como um potente e um inibidor específico da ativação de NFk B. Nós anteriormente mostramos que Y27632, um inibidor de Rho quinase, atenuou a resposta pulmonar das vias aéreas, inflamação e remodelamento. Para o nosso conhecimento, tratamentos com os inibidores de NFk B ou Rho-quinase em comparação com o uso de corticosteroides não foram previamente investigados em um modelo animal de inflamação pulmonar crônica alérgica. MÉTODOS: Trinta camundongos BALB/C machos (20 a 25g) foram divididos em cinco grupos (n=6 em cada grupo): SAL (instilado com solução salina), OVA (expostos à ovalbumina), OVA-CAPE (expostos à ovalbumina e tratados com CAPE), OVA-RHO (expostos à ovalbumina e tratados com inibidor de Rho), OVA-CORT (expostos à ovalbumina e tratados com corticosteróide). Os animais foram sensibilizados para ovalbumina durante 28 dias e os controles receberam solução salina. A administração de corticosteróide (1mg/Kg/dia) e CAPE (10mg/Kg/dia) foi feita por via intraperitoneal e Y-27632 (10 mg/kg) administrado por via intranasal, todos nos dias 22, 24, 26 e 28 do protocolo experimental. Vinte e quatro horas após a conclusão do protocolo experimental, os animais foram submetidos a uma avaliação da curva de resposta à dose à metacolina, consideramos as respostas máximas da Resistência ao Sistema Respiratório (Rrs) e Elastância (Ers) às 24 horas após o último desafio com ovalbumina (respostas basais e máximas após a metacolina desafio 3, 30 e 300mg/mL). Posteriormente, os pulmões foram removidos e a análise histológica foi realizada usando morfometria. RESULTADOS: não houve diferenças nos valores basais de todos os grupos. expostos à ovalbumina Houve um aumento em Rrs e Ers após o desafio da metacolina em comparação com o grupo SAL (p < 0,05). No grupo exposto ao OVA, os tratamentos com CAPE, CORT e RHO reduziram a resposta máxima de Ers em relação ao OVA (p < 0,05). Em relação ao tratamento com somente CAPE atenuou a resposta máxima de Rrs em relação ao OVA (p < 0,05). Houve diminuição nos eosinófilos, conteúdo de fibras de colágeno, células positivas para iNOS, MMP-9, TIMP-1 em grupos OVA-CAPE, OVA-CORT e OVA-RHO em comparação com os animais sensibilizados (grupo OVA) (p < 0,05). CONCLUSÃO: a inibição de NFkB e Rho-quinase contribuiu para o controle da hiperresponsividade, inflamação, processo de remodelamento da matriz extracelular e ativação do estresse oxidativo. Embora os inibidores de NFkB e Rho-quinase sejam uma alternativa ao tratamento da asma, são necessários mais estudos / Although the great majority of asthma patients obtain control with the gold standard treatment using corticosteroids, 5 to 10% of these asthmatics still develop some severe forms of the disease, called difficult to control patients. Activation of NFk B contributes to the maintenance and development of chronic lung inflammation in pathophysiology of asthma. Caffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, is known to have anti-inflammatory and immunomodulatory properties. It is known as a potent and a specific inhibitor of NFk B activation. We previously have shown that Y27632, a Rho-quinase inhibitor, attenuated airway lung responsiveness, inflammation and remodeling. To our knowledge, treatments with the NFk B or Rho-kinase inhibitors compared to the use of corticosteroids have not been previously investigated in an animal model of chronic allergic lung inflammation. METHODS: Thirty male BALB/c mice (20 to 25g) were divided into five groups (n=6 in each group): SAL (saline-instilled), OVA (exposed-ovalbumin), OVA-CAPE (exposedovalbumin and treated with CAPE), OVA-RHO (exposed-ovalbumin and treated with Rho inhibitor), OVA-CORT (exposed-ovalbumin and treated with corticosteroid). The BALB/c mice were sensitized to ovalbumin for 28 days and controls received saline. The administration of corticosteroid (1mg/Kg/day) and CAPE (10mg/Kg/day) was made intraperitoneally and Y-27632 (10mg/kg) was intranasally, all on days 22, 24, 26 and 28 of the experimental protocol. Twentyfour hours after completion of the experimental protocol, animals were subject to an evaluation of dose response curve to methacholine. We considered the maximal responses of respiratory system resistance (Rrs) and elastance (Ers) 24 hours after the last challenge with ovalbumin (baseline and maximal responses after metacholine challenge 3, 30 and 300mg/mL). Afterwards, lungs were removed and histological analysis was performed using morphometry. RESULTS: There were no differences on baseline values of all groups. Ovalbumin-exposed mice had an increase in Rrs and Ers after methacholine challenge compared to SAL group (p < 0.05). In OVA-exposed groups, the treatments with CAPE, CORT and RHO reduced maximal response of %Ers compared to OVA (p < 0.05). In relation to %Rrs only CAPE treatment attenuated the maximal response compared to OVA (p < 0.05). There was a decrease in eosinophils, collagen fibers content, iNOS, MMP-9, TIMP-1 positive cells in OVACAPE, OVA-CORT and OVA-RHO groups compared to only sensitized animals (OVA group) (p < 0.05). CONCLUSION: NFkB and Rho-quinase inhibition contributes to the control of hyperresponsiveness, inflammation, extracellular matrix remodeling process and oxidative stress activation. Although NFkB and Rho-quinase inhibitors were an alternative to asthma treatment, more studies are needed
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Efeitos dos inibidores de NF Kappa-B e Rho Quinase em um modelo de asma animal: comparação com o tratamento com corticosteroides / Effects of NFkB and rho-quinase inhibitors in an animal asthma model: comparison to corticosteroid treatmentFlávia Castro Ribas de Souza 15 December 2017 (has links)
Embora a grande maioria dos pacientes com asma tenha controle com o padrão de tratamento com corticosteroides, 5 a 10% destes asmáticos ainda desenvolvem algumas formas graves da doença e são considerados pacientes difíceis de controlar. A ativação do NFkB contribui para a manutenção e desenvolvimento de inflamação pulmonar crônica na fisiopatologia da asma. O éster fenetilico do ácido cafeico (CAPE), um componente ativo de própolis das colmeias de abelhas, é conhecido por ter propriedades antiinflamatórias e imunomoduladoras. É conhecido como um potente e um inibidor específico da ativação de NFk B. Nós anteriormente mostramos que Y27632, um inibidor de Rho quinase, atenuou a resposta pulmonar das vias aéreas, inflamação e remodelamento. Para o nosso conhecimento, tratamentos com os inibidores de NFk B ou Rho-quinase em comparação com o uso de corticosteroides não foram previamente investigados em um modelo animal de inflamação pulmonar crônica alérgica. MÉTODOS: Trinta camundongos BALB/C machos (20 a 25g) foram divididos em cinco grupos (n=6 em cada grupo): SAL (instilado com solução salina), OVA (expostos à ovalbumina), OVA-CAPE (expostos à ovalbumina e tratados com CAPE), OVA-RHO (expostos à ovalbumina e tratados com inibidor de Rho), OVA-CORT (expostos à ovalbumina e tratados com corticosteróide). Os animais foram sensibilizados para ovalbumina durante 28 dias e os controles receberam solução salina. A administração de corticosteróide (1mg/Kg/dia) e CAPE (10mg/Kg/dia) foi feita por via intraperitoneal e Y-27632 (10 mg/kg) administrado por via intranasal, todos nos dias 22, 24, 26 e 28 do protocolo experimental. Vinte e quatro horas após a conclusão do protocolo experimental, os animais foram submetidos a uma avaliação da curva de resposta à dose à metacolina, consideramos as respostas máximas da Resistência ao Sistema Respiratório (Rrs) e Elastância (Ers) às 24 horas após o último desafio com ovalbumina (respostas basais e máximas após a metacolina desafio 3, 30 e 300mg/mL). Posteriormente, os pulmões foram removidos e a análise histológica foi realizada usando morfometria. RESULTADOS: não houve diferenças nos valores basais de todos os grupos. expostos à ovalbumina Houve um aumento em Rrs e Ers após o desafio da metacolina em comparação com o grupo SAL (p < 0,05). No grupo exposto ao OVA, os tratamentos com CAPE, CORT e RHO reduziram a resposta máxima de Ers em relação ao OVA (p < 0,05). Em relação ao tratamento com somente CAPE atenuou a resposta máxima de Rrs em relação ao OVA (p < 0,05). Houve diminuição nos eosinófilos, conteúdo de fibras de colágeno, células positivas para iNOS, MMP-9, TIMP-1 em grupos OVA-CAPE, OVA-CORT e OVA-RHO em comparação com os animais sensibilizados (grupo OVA) (p < 0,05). CONCLUSÃO: a inibição de NFkB e Rho-quinase contribuiu para o controle da hiperresponsividade, inflamação, processo de remodelamento da matriz extracelular e ativação do estresse oxidativo. Embora os inibidores de NFkB e Rho-quinase sejam uma alternativa ao tratamento da asma, são necessários mais estudos / Although the great majority of asthma patients obtain control with the gold standard treatment using corticosteroids, 5 to 10% of these asthmatics still develop some severe forms of the disease, called difficult to control patients. Activation of NFk B contributes to the maintenance and development of chronic lung inflammation in pathophysiology of asthma. Caffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, is known to have anti-inflammatory and immunomodulatory properties. It is known as a potent and a specific inhibitor of NFk B activation. We previously have shown that Y27632, a Rho-quinase inhibitor, attenuated airway lung responsiveness, inflammation and remodeling. To our knowledge, treatments with the NFk B or Rho-kinase inhibitors compared to the use of corticosteroids have not been previously investigated in an animal model of chronic allergic lung inflammation. METHODS: Thirty male BALB/c mice (20 to 25g) were divided into five groups (n=6 in each group): SAL (saline-instilled), OVA (exposed-ovalbumin), OVA-CAPE (exposedovalbumin and treated with CAPE), OVA-RHO (exposed-ovalbumin and treated with Rho inhibitor), OVA-CORT (exposed-ovalbumin and treated with corticosteroid). The BALB/c mice were sensitized to ovalbumin for 28 days and controls received saline. The administration of corticosteroid (1mg/Kg/day) and CAPE (10mg/Kg/day) was made intraperitoneally and Y-27632 (10mg/kg) was intranasally, all on days 22, 24, 26 and 28 of the experimental protocol. Twentyfour hours after completion of the experimental protocol, animals were subject to an evaluation of dose response curve to methacholine. We considered the maximal responses of respiratory system resistance (Rrs) and elastance (Ers) 24 hours after the last challenge with ovalbumin (baseline and maximal responses after metacholine challenge 3, 30 and 300mg/mL). Afterwards, lungs were removed and histological analysis was performed using morphometry. RESULTS: There were no differences on baseline values of all groups. Ovalbumin-exposed mice had an increase in Rrs and Ers after methacholine challenge compared to SAL group (p < 0.05). In OVA-exposed groups, the treatments with CAPE, CORT and RHO reduced maximal response of %Ers compared to OVA (p < 0.05). In relation to %Rrs only CAPE treatment attenuated the maximal response compared to OVA (p < 0.05). There was a decrease in eosinophils, collagen fibers content, iNOS, MMP-9, TIMP-1 positive cells in OVACAPE, OVA-CORT and OVA-RHO groups compared to only sensitized animals (OVA group) (p < 0.05). CONCLUSION: NFkB and Rho-quinase inhibition contributes to the control of hyperresponsiveness, inflammation, extracellular matrix remodeling process and oxidative stress activation. Although NFkB and Rho-quinase inhibitors were an alternative to asthma treatment, more studies are needed
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Os efeitos do ácido cafeico e do éster fenetil do ácido cafeico sobre as atividades da acetilcolinesterase e das ecto-nucleotidases em ratos / THE EFFECTS OF CAFFEIC ACID AND CAFFEIC ACID PHENETHYL ESTER ON THE ACTIVITIES OF ACETYLCHOLINESTERASE AND ECTO-NUCLEOTIDASES IN RATSAnwar, Javed 21 January 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Phenolic compouds and their derivatives constitute a leading family of natural compounds. Caffeic acid (CA) and
caffeic acid phenethyl ester (CAPE) are the important members of phenolic compound, sharing several biological
applications; antioxidant, neuroprotective, anti-inflammatory, antiproliferative, antibacterial, antiviral, antiatherosclerotic and
anticancer properties. In spite of these, literature reportes some of its pro-oxidants activity depending on cellular
environment. These pathophysiolocal properties increased the interest to evaluate the effect of CA and CAPE on the enzyme
evolved in the purines salvage and the acetylcholine hydrolyzing enzyme the acetylcholineterase (AChE); in both PNS and
CNS, since the essential constituent of our dietary items. Previously, our research group has reported that phenolic compound
altered the activities of these enzymes. The AChE rapidly hydrolyzes the acetylcholine in neuronal and non neuronal tissues,
mediating several neurodegenerative diseases. Beside the ACh, ATP (as co-neurotramittors) and adenosine are important
signaling molecules, communicating cells in both PNS and CNS. In the extracellular signalling pathways; the adenine
nucleotides, their derivative and the coupling of these molecules with specific receptor have a crucial role in nervous,
vascular and immune systems. Once released, these molecules are hydrolyzed by a cascade of enzymes including
ectonucleoside triphosphate diphosphohydrolase (NTPDase; E.C. 3.6.1.5, CD39), 5 -nucleotidase (E.C 3.1.3.5, CD73),
ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP), modulating crucially the signaling pathways in the normal
functioning of nervous, vascular and immune systems. Next, adenosine deaminase (ADA) and xanthin oxidase (XO) degrade
the adenosine and xanthine respectively which further control the functioning mechanisms in cellular events. Found in the
neuronal and non neuronal (in both PNS and CNS) the AChE, NTPDase, 5'-nucleotidase, E-NPP, and ADA regulate several
events including neurotransmission, inflammation, and thrombogenic process. We hypothesized to evaluate first the in vitro
effects of CA on AChE activity in peripheral and central cholinergic system of rats. The results showed that CA significantly
modulated the cholinergic system in vitro. By modulating the cholinergic system in vitro, apparently CA (e.g. phenolic
structure) has proper role in neurotransmission. Therefore we hypothesizes to evaluate the in vivo effects of CA on AChE,
NTPDase, E-NPP, 5'-nucleotidase, platelets aggregation and (ADA) in different tissues/cell from rats. The animals were
treated during 30 days and killed after behavioral test. The results showed that caffeic acid increased significantly the AChE
activity in hippocampus, hyphothalmus, pon and lymphocytes while that in cortex, cerebellum and striatum the AChE was
inhibited. CA improves step-down latencies in the inhibitory avoidance. Investigating the in vivo effects of CA in purinergic
system, caffecid acid increased the ATP and AMP hydrolysis in synaptosomes. However, in the synaptosomes no alterations
were observed in the ADA activity in the groups evaluated in this study. CA increased the ATP and AMP hydrolysis, while
the ADP hydrolysis was decreased in platelets. In the present findings caffeic acid decreased the platelets aggregation
induced by ADP agonist. Treatment with CA also increased the NTPDase and ADA activities in lymphocytes of rats.
Considering the dual function of caffeic acid in vitro and in vivo, the present study was extended to CAPE followed by acute
treatment model (ip) in order to elucidate the effect of another phenolic structure on the same parameters. In this line the
animals were treated (ip) with CAPE and killed after 40 minutes. In platelets, the results showed that the effect of CAPE
increased the NTPDase, E-NPP, 5 -nucleotidase activities, while ADA activities did not change significantly. In
synaptosomes CAPE significantly inhibited the NTPDase, and 5 -nucleotidase activity. CAPE induced no significant changes
in ADA in synaptosomes but reduced XO in whole brain. Finaly we investigated the activity of AChE in cortex, cerebellum,
striatum, hippocampus, hyphotalamus, pon, lymphocytes and muscules of rats treated with CAPE. The results showed that
CAPE significantly decreased the AChE activity in cortex cerebellum and striatum. CAPE significantly increased the AChE
activity in hippocampus hypothalamus, pons, muscle and lymphocytes. In cholinergic system our results clearly
demonstrating that both compound with dual functions.These findings demonstrated that the AChE activities and the cascade
of ecto-enzymes was alter in different tissues after treatment with CA and CAPE in rats, suggesting that these compound
should be considered a potentially therapeutic agent in immune, vascular and neurological disorders related with the
cholinergic purinergic system. / Os compostos fenólicos e seus derivados constituem uma importante família de
compostos naturais. O ácido cafeico (AC) e o éster fenetil do ácido cafeico
(CAPE) são membros importantes dessa família e compartilham algumas
aplicações biológicas, tais como: antioxidante, neuroprotetor, antiinflamatório,
antiproliferativo, antibacteriano, antiviral, antiaterosclerótico e anticancerígeno.
Entretanto, a literatura relata algumas atividades pró-oxidantes, dependendo do
ambiente celular. Devido a estas propriedades patofisiológicas, aumentou o
interesse com o objetivo de avaliar o efeito de CA e CAPE sob as atividades
das enzimas purinérgicas e da acetilcolinesterase (AChE), tanto no Sistema
Nervoso Periférico (SNP) como no Sistema Nervoso Central (SNC).
Previamente, nosso grupo de pesquisa relatou que o composto fenólico tem a
capacidade de alterar as atividades dessas enzimas. A AChE rapidamente
hidrolisa a acetilcolina (ACh) em tecidos neuronais e não neuronais, mediando
algumas doenças neurodegenerativas. Ao lado da ACh, o ATP (como coneurotransmissor)
e adenosina são importantes moléculas sinalizadoras,
comunicando as células em ambos os SNP e do SNC. Nas vias de sinalização
extracelulares, os nucleotídeos de adenina e seus derivados podem ser
acoplados a receptores específicos e desse modo ter um papel crucial no
sistema nervoso, sistema vascular e imune. Uma vez liberadas, estas
moléculas são hidrolisadas por uma cascata de enzimas incluindo a
ectonucleosídeo trifosfato difosfoidrolase (NTPDase; EC 3.6.1.5, CD39), 5'-
nucleotidase (EC 3.1.3.5, CD73), ectonucleotideo pirofosfatase/fosfodiesterase
(E-NPP), modulando definitivamente as vias de sinalização do funcionamento
normal do sistema nervoso, sistema vascular e imune. Além disso, a adenosina
deaminase (ADA) e a xantina oxidase (XO) degradam a adenosina e a xantina,
respectivamente, as quais controlam o funcionamento de mecanismos em
eventos celulares. As enzimas encontradas em tecidos neuronais e não
neuronais como a AChE, a NTPDase, a 5'-nucleotidase, a E-NPP e a ADA
regulam eventos celulares incluindo a neurotransmissão, inflamação e
processos trombogênicos. Com essas informações, nós introduzimos a
hipótese de avaliar primeiramente os efeitos in vitro de CA na atividade da
AChE periférica e no sistema central colinérgico de ratos. Os resultados
demonstraram que o CA modula significativamente o sistema colinérgico no
estudo in vitro. Essa modulação demonstra aparentemente que o CA (estrutura
fenólica) possui propriedades de ação que altera a neurotransmissão. Portanto,
a hipótese de se avaliar os efeitos in vivo de CA na atividade da AChE,
NTPDase, E-NPP, 5'-nucleotidase, ADA e da agregação de plaquetas em
diferentes tecidos de ratos tornou-se evidente. Para esse estudo, os animais
foram tratados durante 30 dias e sacrificados após o teste comportamental. Os
resultados do experimento demonstraram que o CA aumentou
significativamente a atividade da AChE em hipocampo, hipotálamo, ponte e nos
linfócitos, enquanto que no córtex cerebral, cerebelo e estriado a AChE foi
inibida. No teste comportamental o CA teve evolução de melhora na latência de
passos da esquiva inibitória. A investigação dos efeitos in vivo do CA no
sistema purinérgico demonstrou aumento na hidrólise de ATP e AMP em
sinaptossomas. Entretanto, não foram observadas alterações significativas na
atividade da ADA em sinaptossomas dos grupos avaliados neste estudo. Em
plaquetas, o CA aumentou significativamente a hidrólise de ATP e AMP,
enquanto que a hidrólise de ADP foi diminuída nesse tecido. No presente
estudo o CA reduziu significativamente a agregação de plaquetas induzida pelo
agonista ADP. Além disso, o tratamento com CA aumentou significativamente
as atividades da NTPDase e da ADA em linfócitos de ratos. Considerando a
dupla função de CA, in vitro e in vivo, o presente estudo foi estendido para
CAPE seguindo o modelo de tratamento agudo pela via intraperitoneal (ip) com
o objetivo de elucidar o efeito de uma segunda estrutura fenólica sobre os
mesmos parâmetros. Nesta linha de pesquisa, os animais foram tratados ip
com CAPE e eutanasiados após 40 minutos. Em plaquetas, os resultados
demonstraram que o CAPE aumentou significativamente a atividade da
NTPDase, E-NPP e 5'-nucleotidase, enquanto que a atividade da ADA não foi
alterada significativamente. Em sinaptossomas, o CAPE inibiu
significativamente a atividade da NTPDase e da 5'-nucleotidase. O CAPE não
induziu alterações significativas na atividade da ADA em sinaptossomas, mas
reduziu significativamente a atividade da XO em todo o cérebro. Finalmente,
nós investigamos a atividade da AChE no córtex cerebral, cerebelo, estriado,
hipocampo, hipotálamo, ponte, linfócitos e músculos de ratos tratados com
CAPE. Os resultados demonstraram que CAPE diminuiu significativamente a
atividade da AChE em córtex cerebral, cerebelo e estriado. O CAPE aumentou
significativamente a atividade da AChE em hipotálamo, hipocampo, ponte,
músculo e linfócitos. No sistema colinérgico, nossos resultados demonstram
claramente que ambos os compostos possuem dupla função. Estes resultados
demonstram que as atividades da AChE e da cascata das ecto-enzimas foram
alteradas em diferentes tecidos após o tratamento com CA ou CAPE em ratos,
sugerindo que estes compostos devem ser considerados agentes com
potencial terapêutico em doenças imunes, vasculares e neurológicas
relacionadas com o sistema colinérgico e purinérgico.
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Signal transduction mechanisms for stem cell differentation into cardiomyocytesHumphrey, Peter Saah January 2009 (has links)
Cardiovascular diseases are among the leading causes of death worldwide and particularly in the developed World. The search for new therapeutic approaches for improving the functions of the damaged heart is therefore a critical endeavour. Myocardial infarction, which can lead to heart failure, is associated with irreversible loss of functional cardiomyocytes. The loss of cardiomyocytes poses a major difficulty for treating the damaged heart since terminally differentiated cardiomyocytes have very limited regeneration potential. Currently, the only effective treatment for severe heart failure is heart transplantation but this option is limited by the acute shortage of donor hearts. The high incidence of heart diseases and the scarcity donor hearts underline the urgent need to find alternative therapeutic approaches for treating cardiovascular diseases. Pluripotent embryonic stem (ES) cells can differentiate into functional cardiomyocytes. Therefore the engraftment of ES cell-derived functional cardiomyocytes or cardiac progenitor cells into the damaged heart to regenerate healthy myocardial tissues may be used to treat damaged hearts. Stem cell-based therapy therefore holds a great potential as a very attractive alternative to heart transplant for treating heart failure and other cardiovascular diseases. A major obstacle to the realisation of stem cell-based therapy is the lack of donor cells and this in turn is due to the fact that, currently, the molecular mechanisms or the regulatory signal transduction mechanisms that are responsible for mediating ES cell differentiation into cardiomyocytes are not well understood. Overcoming this huge scientific challenge is absolutely necessary before the use of stem cell-derived cardiomyocytes to treat the damaged heart can become a reality. Therefore the aim of this thesis was to investigate the signal transduction pathways that are involved in the differentiation of stem cells into cardiomyocytes. The first objective was the establishment and use of cardiomyocyte differentiation models using H9c2 cells and P19 stem cells to accomplish the specific objectives of the thesis. The specific objectives of the thesis were, the investigation of the roles of (i) nitric oxide (ii) protein kinase C (PKC), (iii) p38 mitogen-activated protein kinase (p38 MAPK) (vi) phosphoinositide 3-kinase (PI3K) and (vi) nuclear factor-kappa B (NF-kB) signalling pathways in the differentiation of stem cells to cardiomyocytes and, more importantly, to identify where possible any points of convergence and potential cross-talk between pathways that may be critical for differentiation to occur. P19 cells were routinely cultured in alpha minimal essential medium (α-MEM) supplemented with 100 units/ml penicillin /100 μg/ml streptomycin and 10% foetal bovine serum (FBS). P19 cell differentiation was initiated by culturing the cells in microbiological plates in medium containing 0.8 % DMSO to form embryoid bodies (EB). This was followed by transfer of EBs to cell culture grade dishes after four days. H9c2 cells were cultured in Dulbecco’s Modified Eagle’s medium (DMEM) supplemented with 10% FBS. Differentiation was initiated by incubating the cells in medium containing 1% FBS. In both models, when drugs were employed, they were added to cells for one hour prior to initiating differentiation. Cell monolayers were monitored daily over a period of 12 or 14 days. H9c2 cells were monitored for morphological changes and P19 cells were monitored for beating cardiomyocytes. Lysates were generated in parallel for western blot analysis of changes in cardiac myosin heavy chain (MHC), ventricular myosin chain light chain 1(MLC-1v) or troponin I (cTnI) using specific monoclonal antibodies. H9c2 cells cultured in 1% serum underwent differentiation as shown by the timedependent formation of myotubes, accompanied by a parallel increase in expression of both MHC and MLC-1v. These changes were however not apparent until 4 to 6 days after growth arrest and increased with time, reaching a peak at day 12 to 14. P19 stem cells cultured in DMSO containing medium differentiated as shown by the timedependent appearance of beating cardiomyocytes and this was accompanied by the expression of cTnI. The differentiation of both P19 stem cells and H9c2 into cardiomyocytes was blocked by the PI3K inhibitor LY294002, PKC inhibitor BIM-I and the p38 MAPK inhibitor SB2035800. However when LY294002, BIM-I or SB2035800 were added after the initiation of DMSO-induced P19 stem cell differentiation, each inhibitor failed to block the cell differentiation into beating cardiomyocytes. The NF-kB activation inhibitor, CAPE, blocked H9c2 cell differentiation into cardiomyocytes. Fast nitric oxide releasing donors (SIN-1 and NOC-5) markedly delayed the onset of differentiation of H9c2 cells into cardiomyocytes while slow nitric oxide releasing donors (SNAP and NOC-18) were less effective in delaying the onset of differentiation or long term differentiation of H9c2 cells into cardiomyocytes. Akt (protein kinase B) is the key downstream target of PI3K. Our cross-talk data also showed that PKC inhibition and p38 MAPK inhibition respectively enhanced and reduced the activation of Akt, as determined by the phosphorylation of Akt at serine residue 473. In conclusion, PKC, PI3K, p38 MAPK and NF-kB are relevant for the differentiation of stem cells into cardiomyocytes. Our data also show that the PKC, PI3K and p38 MAPK signalling pathways are activated as very early events during the differentiation of stem cells into cardiomyocytes. Our data also suggest that PKC may negatively regulate Akt activation while p38 MAPK inhibition inhibits Akt activation. Our fast NO releasing donor data suggest that nitric oxide may negatively regulate H9c2 cell differentiation.
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