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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Valeriana glechomifolia : crescimento e produção de valepotriatos em diferentes meios nutritivos e avaliação preliminar de atividade neurofarmacológica

Maurmann, Natasha January 2006 (has links)
Valeriana glechomifolia é uma espécie vegetal endêmica da região sul do Brasil. Ela acumula valepotriatos em todos os seus órgãos, que são os possíveis componentes sedativos das espécies de Valeriana utilizadas farmaceuticamente. Foi comparado o crescimento in vitro de V. glechomifolia em meios de cultura sólidos Murashige e Skoog completo (MS), com 75% dos nutrientes inorgânicos (MS 75) ou em uma formulação modificada (M ) em culturas mantidas a longo prazo, por até 9 meses sem subcultura. Alterações da biomassa, do desenvolvimento de raízes e partes aéreas, bem como a produção dos valepotriatos acevaltrato, valtrato e diidrovaltrato foram avaliadas mensalmente. O maior aumento de biomassa e desenvolvimento foliar foi detectado em plantas cultivadas em meio MS, e o melhor desenvolvimento radicular foi observado em plantas cultivadas em meio MS modificado (M ) durante o cultivo. A análise por Cromatografia Líquida de Alta Eficiência mostrou que o máximo de rendimento de valtrato e diidrovaltrato foi após os seis meses de cultivo em plantas em meio M , enquanto a maior concentração de acevaltrato foi encontrada em plântulas cultivadas em meio MS 75, após sete meses de cultivo. Os resultados sugerem uma relação direta entre crescimento e acúmulo de valepotriatos, e um efeito positivo do aumento da quantidade de micronutrientes e de mesoinositol nos rendimentos valepotriatos em plantas mantidas em longo período de cultivo. Também foi analisado o efeito neurocomportamental de um extrato contendo uma mistura de valepotriatos (EV) de V. glechomifolia. Camundongos adultos foram tratados com doses de 1, 3 e 10 mg/kg de EV ou veículo, 30 minutos antes dos testes. Durante a exploração no campo aberto, os camundongos tratados com 10 mg/kg mostraram redução na locomoção e no comportamento exploratório (número de rearings) em comparação aos animais controle, e o EV não induziu alteração na ansiedade. Todos os grupos realizaram normalmente a tarefa de memória de reconhecimento de novo objeto, exceto o grupo que recebeu 3 mg/kg, que apresentou piora na memória de reconhecimento do novo objeto. Os resultados indicaram que os camundongos tratados com valepotriatos não apresentaram déficits de memória aversiva de longa duração, e apenas a dose de 3 mg/kg apresentou um prejuízo na tarefa de memória de reconhecimento de novo objeto, além de uma possível propriedade sedativa na dose de 10 mg/kg. / Valeriana glechomifolia is a plant species endemic to southern Brazil. It accumulates the terpene derivatives valepotriates, the presumed sedative components of the pharmaceutically used species of Valeriana, in all of its organs. In vitro growth of V. glechomifolia on solid Murashige and Skoog (MS) without phytohormones at full, 75% (MS 75) or on a modified formulation (M ) was compared in long term stock cultures kept for up to 9 months without subculture. Changes in biomass accumulation, development of roots and shoots, as well as the production of valepotriates acevaltrate, valtrate and didrovaltrate were monthly evaluated. The best root development was observed in plants grown on modified MS medium (M ∆ ), whereas highest biomass accumulation and leaf development were detected in MS medium grown plants throughout the period. High Performance Liquid Chromatography analysis showed maximal valtrate and didrovaltrate yields on M ∆ grown plants harvested after six months of culture, whereas acevaltrate concentration was highest on MS 75 grown plants after seven months of culture. The overall results suggest a direct relationship between growth and valepotriate accumulation, and a positive effect of increases in micronutrient and myo-inositol amounts on valepotriate yields of long-term stock-cultures. An extract containing a mixture of valepotriates (EV) of V. glechomifolia was evaluated in relation to neurobehavioral parameters. Adult mice were treated with doses of 1, 3 and 10 mg/kg of EV or vehicle, 30 minutes before tests. During exploration of an open field, mice treated with 10 mg/kg showed reduced locomotion and reduced exploratory behavior (number of rearings) compared to control animals, and the EV did not induce alterations in anxiety. All groups performed normally the task of novel object recognition memory, except the group receiving 3 mg/kg dose, which showed decrease in novel object recognition memory. The results indicated that mice treated with valepotriates presented no deficits in long-term memory for aversive training and presented an impairment in novel object recognition memory task only at 3 mg/kg, as well as a possible sedative proprieties at 10 mg/kg.
2

Oxidation of pharmaceuticals : impacts of natural organic matter and elimination of residual pharmacological activity

Blaney, Lee Michael 19 September 2011 (has links)
Anthropogenically-derived substances, including pharmaceuticals and personal care products, endocrine-disrupting chemicals, and pesticides, are increasingly being detected in drinking water supplies and wastewater effluents. Concerns over the presence of these compounds in water supplies include their ability to impart toxicological activity, their capacity to spread antibiotic resistance, and their potential to affect cell-signaling processes. For these reasons, water treatment processes geared towards removal of these trace organic contaminants are vital. In this work, ozone was used to treat four pharmaceutical contaminants: ciprofloxacin, cyclophosphamide, erythromycin, and ifosfamide. Ciprofloxacin and erythromycin are antibiotic/antimicrobial compounds, and cyclophosphamide and ifosfamide are chemotherapy agents. Ozone effectively transformed all four pharmaceuticals, even in the presence of background natural organic matter, which exerts a considerable ozone demand. The apparent rate constants for the reaction of the pharmaceuticals with ozone at pH 7 were determined: 3.03 M-1s-1 for cyclophosphamide; 7.38 M-1s-1 for ifosfamide; 1.57×104 M-1s-1 for ciprofloxacin; and 7.18×104 M-1s-1 for erythromycin. Cyclophosphamide and ifosfamide, which do not react quickly with ozone, exhibited high rate constants (2.7×109 M-1s-1) for transformation by hydroxyl radicals, which are formed through ozone decomposition. Nevertheless, complete removal of cyclophosphamide and ifosfamide was achievable using a novel continuous aqueous ozone addition reactor and an ozone-based advanced oxidation process (peroxone). In ozone-based processes, pharmaceuticals are systematically transformed via complex oxidative pathways towards CO2, H2O, and the oxidized forms of other elements. Intermediate oxidation products containing oxygen atoms or hydroxyl groups substituted into the chemical structure of the parent pharmaceutical were identified using liquid chromatography-mass spectrometry (LC-MS). Given the structural similarity of intermediate oxidation products to the parent pharmaceuticals, an antimicrobial activity assay was employed to monitor the removal of pharmacological activity associated with ciprofloxacin, erythromycin, and their respective intermediate oxidation products throughout treatment. For solutions containing ciprofloxacin or erythromycin, ozone was able to completely eliminate the corresponding antimicrobial activity. Ciprofloxacin intermediate oxidation products were pharmacologically active; however, erythromycin’s intermediate products did not contribute to the residual antimicrobial activity. These results suggest that the design of conventional and advanced ozone-based processes must incorporate ozone demand from background organic matter and account for destruction of pharmacologically active intermediates. / text
3

Valeriana glechomifolia : crescimento e produção de valepotriatos em diferentes meios nutritivos e avaliação preliminar de atividade neurofarmacológica

Maurmann, Natasha January 2006 (has links)
Valeriana glechomifolia é uma espécie vegetal endêmica da região sul do Brasil. Ela acumula valepotriatos em todos os seus órgãos, que são os possíveis componentes sedativos das espécies de Valeriana utilizadas farmaceuticamente. Foi comparado o crescimento in vitro de V. glechomifolia em meios de cultura sólidos Murashige e Skoog completo (MS), com 75% dos nutrientes inorgânicos (MS 75) ou em uma formulação modificada (M ) em culturas mantidas a longo prazo, por até 9 meses sem subcultura. Alterações da biomassa, do desenvolvimento de raízes e partes aéreas, bem como a produção dos valepotriatos acevaltrato, valtrato e diidrovaltrato foram avaliadas mensalmente. O maior aumento de biomassa e desenvolvimento foliar foi detectado em plantas cultivadas em meio MS, e o melhor desenvolvimento radicular foi observado em plantas cultivadas em meio MS modificado (M ) durante o cultivo. A análise por Cromatografia Líquida de Alta Eficiência mostrou que o máximo de rendimento de valtrato e diidrovaltrato foi após os seis meses de cultivo em plantas em meio M , enquanto a maior concentração de acevaltrato foi encontrada em plântulas cultivadas em meio MS 75, após sete meses de cultivo. Os resultados sugerem uma relação direta entre crescimento e acúmulo de valepotriatos, e um efeito positivo do aumento da quantidade de micronutrientes e de mesoinositol nos rendimentos valepotriatos em plantas mantidas em longo período de cultivo. Também foi analisado o efeito neurocomportamental de um extrato contendo uma mistura de valepotriatos (EV) de V. glechomifolia. Camundongos adultos foram tratados com doses de 1, 3 e 10 mg/kg de EV ou veículo, 30 minutos antes dos testes. Durante a exploração no campo aberto, os camundongos tratados com 10 mg/kg mostraram redução na locomoção e no comportamento exploratório (número de rearings) em comparação aos animais controle, e o EV não induziu alteração na ansiedade. Todos os grupos realizaram normalmente a tarefa de memória de reconhecimento de novo objeto, exceto o grupo que recebeu 3 mg/kg, que apresentou piora na memória de reconhecimento do novo objeto. Os resultados indicaram que os camundongos tratados com valepotriatos não apresentaram déficits de memória aversiva de longa duração, e apenas a dose de 3 mg/kg apresentou um prejuízo na tarefa de memória de reconhecimento de novo objeto, além de uma possível propriedade sedativa na dose de 10 mg/kg. / Valeriana glechomifolia is a plant species endemic to southern Brazil. It accumulates the terpene derivatives valepotriates, the presumed sedative components of the pharmaceutically used species of Valeriana, in all of its organs. In vitro growth of V. glechomifolia on solid Murashige and Skoog (MS) without phytohormones at full, 75% (MS 75) or on a modified formulation (M ) was compared in long term stock cultures kept for up to 9 months without subculture. Changes in biomass accumulation, development of roots and shoots, as well as the production of valepotriates acevaltrate, valtrate and didrovaltrate were monthly evaluated. The best root development was observed in plants grown on modified MS medium (M ∆ ), whereas highest biomass accumulation and leaf development were detected in MS medium grown plants throughout the period. High Performance Liquid Chromatography analysis showed maximal valtrate and didrovaltrate yields on M ∆ grown plants harvested after six months of culture, whereas acevaltrate concentration was highest on MS 75 grown plants after seven months of culture. The overall results suggest a direct relationship between growth and valepotriate accumulation, and a positive effect of increases in micronutrient and myo-inositol amounts on valepotriate yields of long-term stock-cultures. An extract containing a mixture of valepotriates (EV) of V. glechomifolia was evaluated in relation to neurobehavioral parameters. Adult mice were treated with doses of 1, 3 and 10 mg/kg of EV or vehicle, 30 minutes before tests. During exploration of an open field, mice treated with 10 mg/kg showed reduced locomotion and reduced exploratory behavior (number of rearings) compared to control animals, and the EV did not induce alterations in anxiety. All groups performed normally the task of novel object recognition memory, except the group receiving 3 mg/kg dose, which showed decrease in novel object recognition memory. The results indicated that mice treated with valepotriates presented no deficits in long-term memory for aversive training and presented an impairment in novel object recognition memory task only at 3 mg/kg, as well as a possible sedative proprieties at 10 mg/kg.
4

Valeriana glechomifolia : crescimento e produção de valepotriatos em diferentes meios nutritivos e avaliação preliminar de atividade neurofarmacológica

Maurmann, Natasha January 2006 (has links)
Valeriana glechomifolia é uma espécie vegetal endêmica da região sul do Brasil. Ela acumula valepotriatos em todos os seus órgãos, que são os possíveis componentes sedativos das espécies de Valeriana utilizadas farmaceuticamente. Foi comparado o crescimento in vitro de V. glechomifolia em meios de cultura sólidos Murashige e Skoog completo (MS), com 75% dos nutrientes inorgânicos (MS 75) ou em uma formulação modificada (M ) em culturas mantidas a longo prazo, por até 9 meses sem subcultura. Alterações da biomassa, do desenvolvimento de raízes e partes aéreas, bem como a produção dos valepotriatos acevaltrato, valtrato e diidrovaltrato foram avaliadas mensalmente. O maior aumento de biomassa e desenvolvimento foliar foi detectado em plantas cultivadas em meio MS, e o melhor desenvolvimento radicular foi observado em plantas cultivadas em meio MS modificado (M ) durante o cultivo. A análise por Cromatografia Líquida de Alta Eficiência mostrou que o máximo de rendimento de valtrato e diidrovaltrato foi após os seis meses de cultivo em plantas em meio M , enquanto a maior concentração de acevaltrato foi encontrada em plântulas cultivadas em meio MS 75, após sete meses de cultivo. Os resultados sugerem uma relação direta entre crescimento e acúmulo de valepotriatos, e um efeito positivo do aumento da quantidade de micronutrientes e de mesoinositol nos rendimentos valepotriatos em plantas mantidas em longo período de cultivo. Também foi analisado o efeito neurocomportamental de um extrato contendo uma mistura de valepotriatos (EV) de V. glechomifolia. Camundongos adultos foram tratados com doses de 1, 3 e 10 mg/kg de EV ou veículo, 30 minutos antes dos testes. Durante a exploração no campo aberto, os camundongos tratados com 10 mg/kg mostraram redução na locomoção e no comportamento exploratório (número de rearings) em comparação aos animais controle, e o EV não induziu alteração na ansiedade. Todos os grupos realizaram normalmente a tarefa de memória de reconhecimento de novo objeto, exceto o grupo que recebeu 3 mg/kg, que apresentou piora na memória de reconhecimento do novo objeto. Os resultados indicaram que os camundongos tratados com valepotriatos não apresentaram déficits de memória aversiva de longa duração, e apenas a dose de 3 mg/kg apresentou um prejuízo na tarefa de memória de reconhecimento de novo objeto, além de uma possível propriedade sedativa na dose de 10 mg/kg. / Valeriana glechomifolia is a plant species endemic to southern Brazil. It accumulates the terpene derivatives valepotriates, the presumed sedative components of the pharmaceutically used species of Valeriana, in all of its organs. In vitro growth of V. glechomifolia on solid Murashige and Skoog (MS) without phytohormones at full, 75% (MS 75) or on a modified formulation (M ) was compared in long term stock cultures kept for up to 9 months without subculture. Changes in biomass accumulation, development of roots and shoots, as well as the production of valepotriates acevaltrate, valtrate and didrovaltrate were monthly evaluated. The best root development was observed in plants grown on modified MS medium (M ∆ ), whereas highest biomass accumulation and leaf development were detected in MS medium grown plants throughout the period. High Performance Liquid Chromatography analysis showed maximal valtrate and didrovaltrate yields on M ∆ grown plants harvested after six months of culture, whereas acevaltrate concentration was highest on MS 75 grown plants after seven months of culture. The overall results suggest a direct relationship between growth and valepotriate accumulation, and a positive effect of increases in micronutrient and myo-inositol amounts on valepotriate yields of long-term stock-cultures. An extract containing a mixture of valepotriates (EV) of V. glechomifolia was evaluated in relation to neurobehavioral parameters. Adult mice were treated with doses of 1, 3 and 10 mg/kg of EV or vehicle, 30 minutes before tests. During exploration of an open field, mice treated with 10 mg/kg showed reduced locomotion and reduced exploratory behavior (number of rearings) compared to control animals, and the EV did not induce alterations in anxiety. All groups performed normally the task of novel object recognition memory, except the group receiving 3 mg/kg dose, which showed decrease in novel object recognition memory. The results indicated that mice treated with valepotriates presented no deficits in long-term memory for aversive training and presented an impairment in novel object recognition memory task only at 3 mg/kg, as well as a possible sedative proprieties at 10 mg/kg.
5

Determinação do potencial tripanocida de derivados do ácido copálico / Trypanocidal potential of copalic acids derivatives

Portapilla, Gisele Bulhões 26 September 2014 (has links)
A doença de Chagas é uma das principais Doenças Tropicais Negligenciadas (DTNs) e considerada um importante problema de saúde pública, pois acomete milhares de pessoas e outras, permanecem expostas ao risco de infecção. É descrito que as terapias disponíveis baseadas no benzonidazol e nifurtimox, provocam severos efeitos colaterais, além de possuírem baixa eficácia durante a fase crônica da doença. Estudos fitoquímicos relatam que o oleorresina de copaíba, extraído de árvores do gênero Copaífera, é constituído por diversos terpenos que apresentam alta atividade e seletividade contra Trypanosoma cruzi. Portanto, na busca de moléculas alternativas para tratamento dessa patologia, o objetivo deste trabalho consistiu em determinar o potencial tripanocida in vitro de derivados semissintéticos, obtidos a partir dos terpenos óxido de cariofileno e ácido copálico. O ácido copálico foi obtido por métodos cromatográficos, porém devido às dificuldades encontradas durante a execução do trabalho, não foram obtidos derivados semissintéticos a partir dessa substância embora, algumas das metodologias propostas proporcionaram a obtenção do diterpeno ácido 19-ent-cauranóico, pouco descrito na literatura. As reações de síntese para o óxido de cariofileno resultaram em oito derivados semissintéticos (D1 a D8). Logo, no presente trabalho foram determinadas as atividades biológicas in vitro dos seguintes compostos: óleo de copaíba, ácido 19-ent-cauranóico, ácido copálico, óxido de cariofileno, os derivados D1 a D7 e benzonidazol. D8 foi instável a presença de luz. A atividade citotóxica dos compostos foi avaliada sobre a linhagem celular de mamífero LLC-MK2 e os ensaios tripanocidas, obtidos sobre as formas epimastigotas e tripomastigotas das cepas Y e Bolívia. Todas as substâncias apresentaram citotoxicidade moderada, porém as modificações estruturais em D1, D2, D3 foram importantes por reduzir o efeito tóxico sobre células LLC-MK2. Os derivados semissintéticos do óxido de cariofileno apresentaram maior atividade sobre as formas evolutivas de T. cruzi quando comparados ao produto bruto. Além disso, a ação da maioria dessas substâncias demonstrou ser mais seletiva para os parasitos do que para células de mamífero. Deve-se destacar que a estrutura química de D3 mostrou-se promissora, pois os resultados indicaram que o derivado foi efetivo tanto para reduzir a citotoxicidade quanto por ser ativo para ambas as formas das cepas Y e Bolívia. Os dados obtidos neste trabalho confirmam a efetividade da química orgânica sintética como um mecanismo ímpar para potencializar a ação de substâncias terapeuticamente úteis, de modo que estudos posteriores serão realizados a fim de determinar a atividade desses novos compostos em protocolos in vivo, bem como determinar os possíveis mecanismos de ação dos mesmos, sobre estruturas biológicas ou rotas metabólicas do protozoário T. cruzi. / Chagas\' disease is one of the most important tropical neglected diseases in global public health, affecting thousands of people, and exposing other ones to the infection risk. According to the literature, therapies with benznidazole and nifurtimox cause serious side effects, and show low efficacy during the chronic phase of the disease. Phytochemical studies showed that copaiba oils obtained from threes of Copaifera genus present several terpenes that show high activity and selectivity against Trypanosoma cruzi. In order to search alternative molecules for this treatment, the aim of this study was to determine the in vivo potential trypanocidal effect of semisynthetic derivatives obtained by the terpenes caryophyllene oxide and copalic acid. We obtained copalic acid by chromatographic methods but due some difficulties during the procedure, we could find no semisynthetic derivatives from this substance besides, some purposed methodologies allowed the obtaining of the diterpene acid 19-ent-cauranoic that was not commonly described on the literature. The synthesis reactions for caryophyllene oxide resulted in eight semisynthetic derivatives (D1 to D8). So, we could determine the in vivo biological activities of the following compounds: copaiba oil, acid 19-ent-cauranoic, copalic acid, caryophyllene oxide, D1 to D8 derivatives, and Benznidazole. D8 was unstable in the presence of light. Cytotoxic activities of the compounds were evaluated by cellular mammal strain LLC-MK2 and trypanocidal activity assays, obtained from epimastigotes and trypomastigotes forms of Bolivia and Y strains. All the substances showed high activity on the evolutive forms of T.cruzi when compared with the row product. Besides, the action of great part of the substances has been shown more selectivity for parasites than the mammals´ cells. The test results of chemical structure of D3 showed that its derivative was effective for both cases reducing the toxicity, and being active for Bolivia and Y strains. Obtained data confirmed the effectiveness of the synthetic organic chemistry as a very important way to increase the action of substances therapeutically so useful that posterior studies will be accomplished in order to determine the activity of these new in vivo compounds protocols, as well as to indicate its possible action mechanisms on biological structures or metabolic routes of the protozoa T. cruzi.
6

Determinação do potencial tripanocida de derivados do ácido copálico / Trypanocidal potential of copalic acids derivatives

Gisele Bulhões Portapilla 26 September 2014 (has links)
A doença de Chagas é uma das principais Doenças Tropicais Negligenciadas (DTNs) e considerada um importante problema de saúde pública, pois acomete milhares de pessoas e outras, permanecem expostas ao risco de infecção. É descrito que as terapias disponíveis baseadas no benzonidazol e nifurtimox, provocam severos efeitos colaterais, além de possuírem baixa eficácia durante a fase crônica da doença. Estudos fitoquímicos relatam que o oleorresina de copaíba, extraído de árvores do gênero Copaífera, é constituído por diversos terpenos que apresentam alta atividade e seletividade contra Trypanosoma cruzi. Portanto, na busca de moléculas alternativas para tratamento dessa patologia, o objetivo deste trabalho consistiu em determinar o potencial tripanocida in vitro de derivados semissintéticos, obtidos a partir dos terpenos óxido de cariofileno e ácido copálico. O ácido copálico foi obtido por métodos cromatográficos, porém devido às dificuldades encontradas durante a execução do trabalho, não foram obtidos derivados semissintéticos a partir dessa substância embora, algumas das metodologias propostas proporcionaram a obtenção do diterpeno ácido 19-ent-cauranóico, pouco descrito na literatura. As reações de síntese para o óxido de cariofileno resultaram em oito derivados semissintéticos (D1 a D8). Logo, no presente trabalho foram determinadas as atividades biológicas in vitro dos seguintes compostos: óleo de copaíba, ácido 19-ent-cauranóico, ácido copálico, óxido de cariofileno, os derivados D1 a D7 e benzonidazol. D8 foi instável a presença de luz. A atividade citotóxica dos compostos foi avaliada sobre a linhagem celular de mamífero LLC-MK2 e os ensaios tripanocidas, obtidos sobre as formas epimastigotas e tripomastigotas das cepas Y e Bolívia. Todas as substâncias apresentaram citotoxicidade moderada, porém as modificações estruturais em D1, D2, D3 foram importantes por reduzir o efeito tóxico sobre células LLC-MK2. Os derivados semissintéticos do óxido de cariofileno apresentaram maior atividade sobre as formas evolutivas de T. cruzi quando comparados ao produto bruto. Além disso, a ação da maioria dessas substâncias demonstrou ser mais seletiva para os parasitos do que para células de mamífero. Deve-se destacar que a estrutura química de D3 mostrou-se promissora, pois os resultados indicaram que o derivado foi efetivo tanto para reduzir a citotoxicidade quanto por ser ativo para ambas as formas das cepas Y e Bolívia. Os dados obtidos neste trabalho confirmam a efetividade da química orgânica sintética como um mecanismo ímpar para potencializar a ação de substâncias terapeuticamente úteis, de modo que estudos posteriores serão realizados a fim de determinar a atividade desses novos compostos em protocolos in vivo, bem como determinar os possíveis mecanismos de ação dos mesmos, sobre estruturas biológicas ou rotas metabólicas do protozoário T. cruzi. / Chagas\' disease is one of the most important tropical neglected diseases in global public health, affecting thousands of people, and exposing other ones to the infection risk. According to the literature, therapies with benznidazole and nifurtimox cause serious side effects, and show low efficacy during the chronic phase of the disease. Phytochemical studies showed that copaiba oils obtained from threes of Copaifera genus present several terpenes that show high activity and selectivity against Trypanosoma cruzi. In order to search alternative molecules for this treatment, the aim of this study was to determine the in vivo potential trypanocidal effect of semisynthetic derivatives obtained by the terpenes caryophyllene oxide and copalic acid. We obtained copalic acid by chromatographic methods but due some difficulties during the procedure, we could find no semisynthetic derivatives from this substance besides, some purposed methodologies allowed the obtaining of the diterpene acid 19-ent-cauranoic that was not commonly described on the literature. The synthesis reactions for caryophyllene oxide resulted in eight semisynthetic derivatives (D1 to D8). So, we could determine the in vivo biological activities of the following compounds: copaiba oil, acid 19-ent-cauranoic, copalic acid, caryophyllene oxide, D1 to D8 derivatives, and Benznidazole. D8 was unstable in the presence of light. Cytotoxic activities of the compounds were evaluated by cellular mammal strain LLC-MK2 and trypanocidal activity assays, obtained from epimastigotes and trypomastigotes forms of Bolivia and Y strains. All the substances showed high activity on the evolutive forms of T.cruzi when compared with the row product. Besides, the action of great part of the substances has been shown more selectivity for parasites than the mammals´ cells. The test results of chemical structure of D3 showed that its derivative was effective for both cases reducing the toxicity, and being active for Bolivia and Y strains. Obtained data confirmed the effectiveness of the synthetic organic chemistry as a very important way to increase the action of substances therapeutically so useful that posterior studies will be accomplished in order to determine the activity of these new in vivo compounds protocols, as well as to indicate its possible action mechanisms on biological structures or metabolic routes of the protozoa T. cruzi.
7

Rational drug design approach of the myeloperoxidase inhibition: From in silico to pharmacological activity

Aldib, Iyas 16 December 2016 (has links) (PDF)
1. SUMMARYMyeloperoxidase (MPO) which belongs to the peroxidase family, is found in mammalian neutrophils. This heme enzyme contributes to the production of (pseudo)halogenous acid such as HOCl which oxidizes proteins, cell membrane, DNA and RNA causing death for the pathogens. It has an antimicrobial effect due to HOCl secreting inside the phagosomes of the neutrophils, whereas it will be released outside neutrophils causing oxidative damages for the host tissues. Proteins, lipids, lipoproteins, DNA and RNA are potential targets of the MPO resulting in several chronic syndromes. Many researchers have discovered the harmful effects of MPO and its products demonstrating its role in many inflammatory chronic diseases such as: Cardiovascular diseases as in atherosclerosis. MPO contribution in atherosclerosis development has been demonstrated. Neurodegenerative diseases also was related to MPO: such as Alzheimer’s disease (AD), multiple sclerosis (MSc) and Parkinson’s disease The enzyme has been also pointed out in other diseases such as renal disease and cancer.For these reasons, MPO as a target of drug discovery has attracted the attention of many researchers. X-ray 3D structures were resolved for this enzyme, biological activity and mechanism of action were investigated in depth, and many medicinal chemists have investigated and screened for new MPO inhibitors. Indeed, this cumulative work including X-ray data, the role of MPO in different pathologies, MPO inhibitory mechanism of action, screening and various chemical entities that inhibit MPO, provided sufficient elements to start a new drug design and drug discovery process on MPO.The aim of the present study was to apply a rational drug design approach to the myeloperoxidase inhibition: from in silico to pharmacological activity. This includes:─ Conducting high throughput virtual screening in order to find new potential hits to inhibit MPO followed by mechanism of inhibition determination. ─ Selecting one hit and then implementing a whole pharmacomodulation process in order to increase the potency of the inhibition greater than the starting hit and to improve the selectivity.Firstly, a rational drug design process was launched to find new hits using high throughput virtual screening. The chosen database for the screening was ASINEX database published in ZINC.X-ray structure of human peroxidase complexed to cyanide and thiocyanate (PDB 1DNW) was selected to conduct High-Throughput Virtual Screening (HTVS). Three successive protocols with different levels of accuracy in the docking and scoring processes were used starting with HTVS, followed by Standard Precision (SP) and finally with Xtra Precision (XP). The quality of the docking process performed was validated by docking a set of 60 chosen molecules of varying chemical structure and known as MPO inhibitors. From the result of the HTVS conducted on 1,350,000 compounds, the 100 best compounds were selected. Among them, 81 molecules were available for purchase from ASINEX, those compounds were tested with a MPO inhibition assay. Thirty-two compounds (39 %) were active, but only 8 compounds were selected, featuring different chemical structures with IC50 values ranging between 0.46 ± 0.07 and 12 ± 3 μM. Among these molecules, two compounds were the best and considered as hits. One has purinedione structure which is similar with the structure of thioxanthine derivatives (F9, IC50=0.46±0.07μM). The second compound has a hexahydropyrimidine structure (A1, IC50 = 0.5 ± 0.1 μM) The most common interactions found among all 8 docked ligands are the ionic bond with Glu102 and a stacking (shifted or not) with pyrrole ring D of the prosthetic group. Hydrogen bonds with Glu102, Thr100, Gln91, Arg239, or the propionate groups of the heme are also found in several docked geometries of the complexes. Interestingly, interactions with Glu102 and pyrrole ring D of the heme were also seen with fluorotryptamine derivatives and also salicylhydroxamic acid (SHA).For measuring MPO-dependent LDL oxidation, the two best compounds were tested. Compounds A1 and F9 showed good inhibition on MPO-dependent LDL oxidation (62 ± 6, 4.5 ± 0.9, 11 ± 2% and 11 ± 2, 2.6 ± 0.8, 6 ± 4%, respectively).Consequently, in order to determine the mechanism of inhibition transient-state kinetics were further investigated of all the 8 selected compounds.Both new lead compounds (A1 and F9) act as electron donors of both Compound I and Compound II of MPO. The reaction with Compound I was significantly faster (k2 ≫ k3). As a consequence, the enzyme is trapped in the Compound II state. They reversibly inactivated the enzyme blocking the harmful halogenation activity of MPO by transferring it to the MPO peroxidase cycle. In the present study, 8 active and reversible MPO inhibitors were selected. They act as electron donors of the oxidoreductase and efficiently block the halogenation activity with reversible inactivation. Two of the selected compounds have a submicromolar activity and inhibit MPO-dependent LDL oxidation. The high-throughput virtual screening was proved to be a successful tool to find new leads of MPO inhibitors. Conducting HTVS on a large-scale database enabled selection of novel scaffolds of MPO inhibitors never explored before in less time and at less expenses.Finding 8 new different chemical scaffolds through the first step of this drug discovery process led us to choose a new hit, compound A1, which has a hexahydropyrimidine structure, compound F9 was not chosen despite being more active due to its similarity to compounds discovered by AstraZeneca. To conduct pharmacomodulation, a validation of the docking procedure was conducted by comparing the X-ray structures of MPO with 2-(3,5-bistrifluoromethylbenzylamino)-6-oxo-1H-pyrimidine-5- carbohydroxamic acid, HX1, and SHA in the X-ray structures of human MPO in complex with cyanide and thiocyanate (PDB code 1DNW) as well as in complex with HX1 (PDB code 4C1M). Compound A1 was docked into both target structures 1DNW and 4C1M. In both cases, A1 showed almost the same poses.Based on the binding modes of A1, different strategies were developed for the design of derivatives which were mainly focused on the substitution of the aromatic rings A and B, the 2 amino groups and the side chain bridges.Pharmacomodulation was carried out on the hit A1 with different strategies:─ Investigating the role of hydroxyl groups on both aromatic rings─ Shifting the position of the amino groups in the hexahydropyrimidine ring to obtain piperazine derivatives and introduction of fluorine ─ Eliminating of one ring and of an amino group in the hexahydropyrimidine ring leading to piperidine derivatives ─ Opening the hexahydropyrimidine ring while keeping amine function and changing the length of the bridge between this amino group and aromatic ring as well as the impact of substitutions on aromatic rings.─ Hybridization of fluorotryptamine derivatives (effective MPO inhibitors) with hit A1.Based on of the docking experiments, 37 designed compounds were synthesized. The assessment of inhibition of the chlorination activity of MPO was undertaken over the 37 compounds. The hit A1 IC50 = 500 nM. The best compounds inhibiting MPO exhibited the following characteristics:─ One amino group on the bridge between aromatic rings was sufficient for the establishment of binding to Glu102 ─ The presence of three methylene groups between the secondary amine and an aromatic ring improved the inhibition of chlorination and thus decreased the IC50 values. These results showed that the position of the hydroxyl group is important. The distance between the hydrogen bond acceptor (HBA) group of one aromatic ring and the amino group is very important. The docking experiments of bisarylpropylamine derivatives showed ionic and hydrogen bonding interactions between Glu102 and hydroxyl group on aromatic ring linked to the longer side chain.─ Hybridized compounds which carry a fluorotryptamine instead of the phenol ring obtained by hybridization of hit A1 and the potent MPO inhibitors fluorotryptamine derivatives. Actually, compound 38 (which had one aromatic ring and a propyl bridge attached to indole ring) had an IC50 = 54 nM which was 10 times more powerful than the starting hit.The 3 best compounds were tested to examine the transient kinetics. They act as electron donors of the oxidoreductase and efficiently shift MPO from the chlorination cycle to the peroxidase cycle. Due to the similarity of the best compound 38 to serotonin it was tested with the two other best compounds on serotonin transporter (SERT) to examine the selectivity between MPO and SERT.Compound 38 had higher selectivity over MPO but the best selective compound was 28 that contains two aromatic rings carrying one hydroxyl and one fluorine.Electron density maps were conducted to predict the site of oxidation. Results suggested it occurs preferentially at the benzene ring or the indole ring in the best compounds.Determination of redox potentials for the synthesized compounds were tested. Best compounds act as electron donors allowing a one-electron reduction of Compound I.In conclusion, the present study succeeded through rational drug design including structure-based drug design and HTVS to identify new chemical entities for MPO inhibition. Eight compounds were more active than the starting hit A1 with submicromolar inhibition potency. Hybridization and structure based design also gave improvement of selectivity of inhibitors against MPO such as compound 38. Bis-arylalkylamine derivatives are a new group of MPO inhibitors with higher selectivity which could be a new hit for future development. / Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie) / info:eu-repo/semantics/nonPublished
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Studium působení tyrosinkinasových inhibitorů a jejich metabolitů na buněčné linie nádorů / Study of effects of tyrosine kinase inhibitors and their metabolites on tumour cell lines

Kolárik, Matúš January 2021 (has links)
Vandetanib, lenvatinib and cabozantinib are inhibitors of receptor tyrosine kinases approved to treat locally advanced or metastatic thyroid gland, kidney and liver cancers. These multi- kinase inhibitors, inhibit phosphorylation of tyrosine moieties of protein, thus modulate cell signalization in cancer cells. Metabolites of vandetanib, lenvatinib and cabozantinib were detected in vitro as well as in vivo in blood and urine. Cytochromes P450 and flavin monooxygenases were identified as primary enzymes participating in metabolism of these drugs. Literature lacks information regarding pharmacological efficacy of vandetanib, lenvatinib and cabozantinib metabolites. The aim of this diploma thesis was the investigation of pharmacological efficacy of N-oxides of vandetanib, lenvatinib and cabozantinib. The viability measurement under normoxic and hypoxic conditions was employed to determined their efficacy. The expression of enzymes of the first phase of xenobiotics metabolism (CYP 450 1A1, 1B1, 3A4 a CYP 450 oxidoreductase) and receptor tyrosine kinases RET and VEGFR2, as well as mechanism of changes in their expression were investigated using western blotting and flow cytometry. High performance liquid chromatography was utilised to investigate possible metabolism of tyrosine kinase inhibitors and...
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Estudo de metalofármacos antiinflamatórios de cobre e dos materiais híbridos resultantes de suas imobilizações no hidróxido duplo lamelar hidrotalcita: síntese, caracterização e avaliação da atividade farmacológica / Studies of Anti-inflammatory Copper-based Drugs and Corresponding Hybrid Materials from their Immobilization on the Layered Double Hydroxide Hydrotalcite: Synthesis, Characterization and Evaluation of Pharmacological Activities

Gordijo, Cláudia Regina 04 October 2007 (has links)
Os fármacos antiinflamatórios não-esteróides (FAINEs) são amplamente utilizados no combate a processos inflamatórios e dores, mas apresentam restrição de uso em razão de sérios efeitos colaterais sobre o trato gastrointestinal. A atividade biológica de complexos metálicos tem sido objeto de pesquisa de grande interesse na área de metalofármacos e compostos do tipo Cu(II)-FAINEs apresentam boa atividade antiinflamatória e efeitos colaterais reduzidos em relação aos fármacos orgânicos. Nesse trabalho, com o objetivo de contribuir para ampliar os estudos sobre o desenvolvimento de alternativas aos FAINEs, foram preparados e caracterizados complexos cobre(lI) com ibuprofeno, indometacina, naproxeno, sulindaco, meloxicam. Os compostos foram imobilizados em Hidrotalcita, um hidróxido duplo lamelar (HDL) de magnésio e alumínio (Mg/AI = 3) que é biocompatível e tem uso como antiácido estomacal. As interações dos metalofármacos com o HDL geraram materiais híbridos bioinorgânicos do tipo Cu-FAINElHDL, nos quais os complexos podem estar presentes de duas maneiras: intercalados entre as Ia meias ou adsorvidos nas superfícies externas do hidróxido duplo lamelar, dependendo do solvente utilizado. A intercalação de complexos neutros é favorecida em solvente misto álcooVamida no qual a Hidrotalcita sofre esfoliação promovida por um processo de hidrólise da amida. A estabilidade alguns dos complexos e dos materiais híbridos em condições gástricas simuladas (pH e temperatura) e as atividades antiinflamatória, analgésica e ulcerogênica in vivo dos sistemas contendo indometacina (Indo) foram investigadas. A intercalação do complexo Cu-Indo no HDL favorece sua estabilização, contribuindo para potencializar a sua atividade farmacolágica. Os materiais híbridos bioinorgânicos obtidos neste trabalho apresentam propriedades interessantes com vistas a potencial aplicação como sistemas de liberação controlada de fármacos. / Non-steroidal anti-inflammatory drugs are widely consumed to treat inflammatory diseases and pain but their clinical use are limited due to serious side-effects on the gastrointestinal tract. The bioactivity of metal complexes exhibits great interest in metal-based drug research. Cu(II)-NSAID compounds show good anti-inflammatory property and decreased side-effects compared to their organic parent drugs. This work aimed to contribute for development of alternative NSAIDs. Cu-NSAlD compounds containing the drugs Ibuprofen, Indomethacin, Naproxen, Sulindac and Meloxicam were synthesized and characterized. The compounds were also immobilized on Hydrotalcite, a layered double hydroxide (LDH) of magnesium and aluminum (Mg/Al = 3), that is biocompatible and used as stomach antacid. The interactions of the copper drugs with LDH led to Cu-NSAID/LDH- bioinorganic hybrid materiais. Two kinds of complex-LDH interactions were observed by changing the solvent: intercalation between LDH layers or adsorption on the LDH external surfaces. The intercalation of neutral complexes is favored in an alcohollamide solvent mixture where Hydrotalcite undergoes exfoliation process promoted by the amide hydrolysis. The stability of some complexes and their correspondent hybrid materials under gastric conditions (pH and temperature) and also in vivo anti-inflammatory, analgesic and ulcerogenic activities for Indomethacin (Indo)-containing systems were investigated. The stabilization of the Cu-Indo structure is promoted by intercalation of the complex into the LDH layers, contributing to increase its pharmacological activity. The bioinorganic hybrid materials here investigated also exhibit interesting properties for applications as controlled drug delivery systems.
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Estudo de metalofármacos antiinflamatórios de cobre e dos materiais híbridos resultantes de suas imobilizações no hidróxido duplo lamelar hidrotalcita: síntese, caracterização e avaliação da atividade farmacológica / Studies of Anti-inflammatory Copper-based Drugs and Corresponding Hybrid Materials from their Immobilization on the Layered Double Hydroxide Hydrotalcite: Synthesis, Characterization and Evaluation of Pharmacological Activities

Cláudia Regina Gordijo 04 October 2007 (has links)
Os fármacos antiinflamatórios não-esteróides (FAINEs) são amplamente utilizados no combate a processos inflamatórios e dores, mas apresentam restrição de uso em razão de sérios efeitos colaterais sobre o trato gastrointestinal. A atividade biológica de complexos metálicos tem sido objeto de pesquisa de grande interesse na área de metalofármacos e compostos do tipo Cu(II)-FAINEs apresentam boa atividade antiinflamatória e efeitos colaterais reduzidos em relação aos fármacos orgânicos. Nesse trabalho, com o objetivo de contribuir para ampliar os estudos sobre o desenvolvimento de alternativas aos FAINEs, foram preparados e caracterizados complexos cobre(lI) com ibuprofeno, indometacina, naproxeno, sulindaco, meloxicam. Os compostos foram imobilizados em Hidrotalcita, um hidróxido duplo lamelar (HDL) de magnésio e alumínio (Mg/AI = 3) que é biocompatível e tem uso como antiácido estomacal. As interações dos metalofármacos com o HDL geraram materiais híbridos bioinorgânicos do tipo Cu-FAINElHDL, nos quais os complexos podem estar presentes de duas maneiras: intercalados entre as Ia meias ou adsorvidos nas superfícies externas do hidróxido duplo lamelar, dependendo do solvente utilizado. A intercalação de complexos neutros é favorecida em solvente misto álcooVamida no qual a Hidrotalcita sofre esfoliação promovida por um processo de hidrólise da amida. A estabilidade alguns dos complexos e dos materiais híbridos em condições gástricas simuladas (pH e temperatura) e as atividades antiinflamatória, analgésica e ulcerogênica in vivo dos sistemas contendo indometacina (Indo) foram investigadas. A intercalação do complexo Cu-Indo no HDL favorece sua estabilização, contribuindo para potencializar a sua atividade farmacolágica. Os materiais híbridos bioinorgânicos obtidos neste trabalho apresentam propriedades interessantes com vistas a potencial aplicação como sistemas de liberação controlada de fármacos. / Non-steroidal anti-inflammatory drugs are widely consumed to treat inflammatory diseases and pain but their clinical use are limited due to serious side-effects on the gastrointestinal tract. The bioactivity of metal complexes exhibits great interest in metal-based drug research. Cu(II)-NSAID compounds show good anti-inflammatory property and decreased side-effects compared to their organic parent drugs. This work aimed to contribute for development of alternative NSAIDs. Cu-NSAlD compounds containing the drugs Ibuprofen, Indomethacin, Naproxen, Sulindac and Meloxicam were synthesized and characterized. The compounds were also immobilized on Hydrotalcite, a layered double hydroxide (LDH) of magnesium and aluminum (Mg/Al = 3), that is biocompatible and used as stomach antacid. The interactions of the copper drugs with LDH led to Cu-NSAID/LDH- bioinorganic hybrid materiais. Two kinds of complex-LDH interactions were observed by changing the solvent: intercalation between LDH layers or adsorption on the LDH external surfaces. The intercalation of neutral complexes is favored in an alcohollamide solvent mixture where Hydrotalcite undergoes exfoliation process promoted by the amide hydrolysis. The stability of some complexes and their correspondent hybrid materials under gastric conditions (pH and temperature) and also in vivo anti-inflammatory, analgesic and ulcerogenic activities for Indomethacin (Indo)-containing systems were investigated. The stabilization of the Cu-Indo structure is promoted by intercalation of the complex into the LDH layers, contributing to increase its pharmacological activity. The bioinorganic hybrid materials here investigated also exhibit interesting properties for applications as controlled drug delivery systems.

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