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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

Clinical pharmacokinetics of amitriptyline and nortriptyline in relation to CYP2D6 mediated metabolism

Ghahramani, Parviz January 1998 (has links)
No description available.
2

Desenvolvimento e validação de análise de duloxetina em plasma humano, simultânea a outros antidepressivos, por cromatografia líquida de alta eficiência / Development and validation of analysis of duloxetine in human plasma, simultaneous with other antidepressants, by high performance liquid chromatography.

Silva, William Kleber da 26 November 2014 (has links)
Atualmente, a quantidade de pacientes que são diagnosticados com alguma forma de depressão, entre elas, o transtorno depressivo maior, aumenta consideravelmente, quer seja em razão de diagnósticos mais precisos ou pela própria epidemiologia da doença. Acresça-se o fato de que muitos pacientes, apesar da quantidade de tipos de antidepressivos atualmente disponíveis para a terapêutica, são refratários ao tratamento prescrito, em razão dos efeitos adversos apresentados, ou de seus efeitos tóxicos, ou ainda por simplesmente não se observar melhora com a prescrição seguida. Portanto, novos tratamentos farmacológicos são disponibilizados, e entre eles, a duloxetina, um duplo inibidor de recaptação de serotonina e norepinefrina. Para auxiliar na máxima eficácia em sua utilização, esse trabalho apresenta metodologia em HPLC para determinação simultânea de sete antidepressivos, tricíclicos e não tricíclicos, moclobemida, venlafaxina, citalopram, agomelatina, duloxetina, amitriptilina e sertralina, em plasma humano, para posteriormente ser aplicada na monitorização de pacientes depressivos. O simples e preciso método de preparo da amostra consiste na extração líquido-líquido, com recuperação entre 73% a 86% (exceto para moclobemida, de 55%), e para a duloxetina, de aproximadamente 73%. A separação foi obtida usando uma coluna em fase reversa Lichrospher® 60 RP-select B em LichroCART 250mm x 4mm, 5?m de diâmetro interno, Merck, sob condições isocráticas, com detecção em UV em 230nm, com fase móvel composta por 35% de uma mistura de acetonitrila:metanol 55/5 (v/v) e 65% de tampão acetato 0,25M, pH 4,4. As curvas padrões foram lineares em uma faixa de trabalho de 2,5-1000ng/mL para moclobemida, 5-2000ng/mL para venlafaxina, citalopram, agomelatina, duloxetina e amitriptilina, e 10-2000ng/mL para sertralina. As precisões intra e interensaios foram efetuadas em três concentrações (50, 200 e 500ng/mL). Os coeficientes de variação para a precisão intraensaio foram menores que 8,6% para todos os compostos e os coeficientes de variação para a precisão interensaio foram menores que 8,5%. Os limites de quantificação foram de 2,5ng/mL para a moclobemida, 5ng/mL para venlafaxina, citalopram, duloxetina, agomelatina, amitriptilina e 10ng/mL para sertralina. Não se observou qualquer interferência das drogas normalmente associadas aos antidepressivos. / Currently, the number of patients who are diagnosed with some form of depression, among them, major depressive disorder, increases considerably, either because of more accurate diagnosis or by the epidemiology of the disease. One should add the fact that many patients, despite the amount of types of antidepressants currently available for therapy are refractory to the treatment prescribed, because of the adverse effects appear, or their toxic effects, or by simply not observed improvement then the prescription. Therefore, new pharmacological treatments are available, and among them, duloxetine, a dual reuptake inhibitor of serotonin and norepinephrine. To assist in maximum effectiveness in its use, this paper presents a methodology on HPLC for simultaneous determination of seven antidepressants, tricyclic and non-tricyclic, moclobemide, venlafaxine, citalopram, agomelatine, duloxetine, amitriptyline and sertraline in human plasma, later to be applied in monitoring depressed patients. The simple and accurate method of sample preparation consists of the liquid-liquid extraction with recovery between 73% to 86% (except for moclobemide, 55%), and duloxetine, of approximately 73%. Separation was achieved using a reverse phase column Lichrospher® 60 RP-select B LiChroCART 4mm x 250mm, 5?m internal diameter, Merck, under isocratic conditions, with UV detection at 230nm, with a mobile phase consisting of a mixture of 35% acetonitrile:methanol 55/5 (v/v) and 65% 0.25M acetate buffer, pH 4.4. The standard curves were linear in the working range of 2,5-1000ng/mL for moclobemide, 5-2000ng/mL to venlafaxine, citalopram, agomelatine, duloxetine and amitriptyline and 10-2000ng/mL to sertraline. The intra and interassay precisions were performed at three concentrations (50, 200 and 500ng/mL). The coefficients of variation for intra-assay precision were less than 8.6% for all compounds and the coefficients of variation for interassay precision were lower than 8.5%. The limits of quantification were 2.5ng/mL for moclobemide, 5ng/mL for venlafaxine, citalopram, duloxetine, agomelatine, amitriptyline and 10ng/mL for sertraline. No interference of drugs normally associated with antidepressants was observed.
3

Desenvolvimento e validação de análise de duloxetina em plasma humano, simultânea a outros antidepressivos, por cromatografia líquida de alta eficiência / Development and validation of analysis of duloxetine in human plasma, simultaneous with other antidepressants, by high performance liquid chromatography.

William Kleber da Silva 26 November 2014 (has links)
Atualmente, a quantidade de pacientes que são diagnosticados com alguma forma de depressão, entre elas, o transtorno depressivo maior, aumenta consideravelmente, quer seja em razão de diagnósticos mais precisos ou pela própria epidemiologia da doença. Acresça-se o fato de que muitos pacientes, apesar da quantidade de tipos de antidepressivos atualmente disponíveis para a terapêutica, são refratários ao tratamento prescrito, em razão dos efeitos adversos apresentados, ou de seus efeitos tóxicos, ou ainda por simplesmente não se observar melhora com a prescrição seguida. Portanto, novos tratamentos farmacológicos são disponibilizados, e entre eles, a duloxetina, um duplo inibidor de recaptação de serotonina e norepinefrina. Para auxiliar na máxima eficácia em sua utilização, esse trabalho apresenta metodologia em HPLC para determinação simultânea de sete antidepressivos, tricíclicos e não tricíclicos, moclobemida, venlafaxina, citalopram, agomelatina, duloxetina, amitriptilina e sertralina, em plasma humano, para posteriormente ser aplicada na monitorização de pacientes depressivos. O simples e preciso método de preparo da amostra consiste na extração líquido-líquido, com recuperação entre 73% a 86% (exceto para moclobemida, de 55%), e para a duloxetina, de aproximadamente 73%. A separação foi obtida usando uma coluna em fase reversa Lichrospher® 60 RP-select B em LichroCART 250mm x 4mm, 5?m de diâmetro interno, Merck, sob condições isocráticas, com detecção em UV em 230nm, com fase móvel composta por 35% de uma mistura de acetonitrila:metanol 55/5 (v/v) e 65% de tampão acetato 0,25M, pH 4,4. As curvas padrões foram lineares em uma faixa de trabalho de 2,5-1000ng/mL para moclobemida, 5-2000ng/mL para venlafaxina, citalopram, agomelatina, duloxetina e amitriptilina, e 10-2000ng/mL para sertralina. As precisões intra e interensaios foram efetuadas em três concentrações (50, 200 e 500ng/mL). Os coeficientes de variação para a precisão intraensaio foram menores que 8,6% para todos os compostos e os coeficientes de variação para a precisão interensaio foram menores que 8,5%. Os limites de quantificação foram de 2,5ng/mL para a moclobemida, 5ng/mL para venlafaxina, citalopram, duloxetina, agomelatina, amitriptilina e 10ng/mL para sertralina. Não se observou qualquer interferência das drogas normalmente associadas aos antidepressivos. / Currently, the number of patients who are diagnosed with some form of depression, among them, major depressive disorder, increases considerably, either because of more accurate diagnosis or by the epidemiology of the disease. One should add the fact that many patients, despite the amount of types of antidepressants currently available for therapy are refractory to the treatment prescribed, because of the adverse effects appear, or their toxic effects, or by simply not observed improvement then the prescription. Therefore, new pharmacological treatments are available, and among them, duloxetine, a dual reuptake inhibitor of serotonin and norepinephrine. To assist in maximum effectiveness in its use, this paper presents a methodology on HPLC for simultaneous determination of seven antidepressants, tricyclic and non-tricyclic, moclobemide, venlafaxine, citalopram, agomelatine, duloxetine, amitriptyline and sertraline in human plasma, later to be applied in monitoring depressed patients. The simple and accurate method of sample preparation consists of the liquid-liquid extraction with recovery between 73% to 86% (except for moclobemide, 55%), and duloxetine, of approximately 73%. Separation was achieved using a reverse phase column Lichrospher® 60 RP-select B LiChroCART 4mm x 250mm, 5?m internal diameter, Merck, under isocratic conditions, with UV detection at 230nm, with a mobile phase consisting of a mixture of 35% acetonitrile:methanol 55/5 (v/v) and 65% 0.25M acetate buffer, pH 4.4. The standard curves were linear in the working range of 2,5-1000ng/mL for moclobemide, 5-2000ng/mL to venlafaxine, citalopram, agomelatine, duloxetine and amitriptyline and 10-2000ng/mL to sertraline. The intra and interassay precisions were performed at three concentrations (50, 200 and 500ng/mL). The coefficients of variation for intra-assay precision were less than 8.6% for all compounds and the coefficients of variation for interassay precision were lower than 8.5%. The limits of quantification were 2.5ng/mL for moclobemide, 5ng/mL for venlafaxine, citalopram, duloxetine, agomelatine, amitriptyline and 10ng/mL for sertraline. No interference of drugs normally associated with antidepressants was observed.
4

Antidepressants and the Risk of Dental Caries in Children and Adolescents : A Systematic Literature Review

Stahre, Linda, Svensson, Johanna January 2023 (has links)
This thesis aims to review if there is an association between antidepressants and caries in children and adolescents. Previous established evidence exhibits that adults prescribed tricyclic antidepressants have an increased risk of caries. Simultaneously, a global trend of increased prescriptions of antidepressant medications is seen. In Sweden during 2018, 0–17-year old’s on antidepressant medication represented 1,6% percent of the total population. It is of utmost relevance to investigate the association between antidepressants and caries as the increasing population of medicating children may lead to an increased caries prevalence. A systematic literature review was performed in accordance with PRISMAs guidelines. The title-abstract and keywords searches were conducted in the following seven bibliographic databases: PubMed, EMBASE, CINAHL, Scopus, Web of Science, PsycINFO and MedLine. The search consisted of blocks based on “caries”, “children” and “antidepressants”. Unique articles were reviewed from title and abstract. Articles that met the criteria were reviewed in full text. The search generated 1829 unique articles, 1891 were excluded from the predefined criteria. 10 articles were reviewed in full text. None of the articles were eligible within the criteria of inclusion. The conclusion is that further research is needed in this area to assess the possible association between antidepressants and caries in children and adolescents. / Uppsatsen syftar till att sammanställa forskningsläget för sambandet mellan antidepressiv medicinering och karies hos barn och ungdomar. Tidigare evidens visar att vuxna som medicinerar med tricykliska antidepressiva har ökad kariesrisk. Samtidigt kan man globalt se en generell förskrivningsökning av antidepressiva. I Sverige under 2018, utgjorde användarna av antidepressiva i åldersgruppen 0–17 år 1,6% av totalpopulationen. Det är av högsta relevans att undersöka om det finns en potentiell association mellan antidepressiva och karies finns då den ökande populationen av medicinerande barn kan medföra ökad kariesprevalens. En systematisk litteraturöversikt genomfördes enligt PRISMAs riktlinjer. Titel- sammanfattnings och nyckelordssökningen utnyttjade följande sju elektroniska databaser: PubMed, EMBASE, CINAHL, Scopus, Web of Science, PsycINFO och MedLine. Sökningen utfördes i block utifrån “karies”, “barn” och “antidepressiva”. Unika artiklar granskades utifrån titel och abstrakt. Artiklar som uppfyllde förutbestämda kriterier för inklusion granskades i fulltext. Utifrån sökningen påträffades 1829 unika artiklar, varav 1819 exkluderades utifrån från titel och abstrakt. 10 artiklar granskades i fulltext och vi konstaterade att ingen artikel uppfyllde kriterierierna. Slutsatsen för studien är att fler studier och mer forskning behövs inom området. Detta för att kunna svara på om det finns ett samband mellan antidepressiva och karies hos barn.
5

Padronização e validação do método extração sortiva em barra de agitação e cromatografia líquida de alta eficiência (SBSE/HPLC) para a determinação de antidepressivos em amostras de plasma / Standardization and validation of the stir-bar sorptive-extraction and high-performance liquid chromatography (SBSE/HPLC) method for antidepressant determination in plasma samples

Silva, Silvana Maciel 13 April 2007 (has links)
A monitorização terapêutica permite a individualização do regime de dosagem, assegurando a eficácia clínica e minimizando os efeitos adversos dos fármacos, prescritos na clínica. Os antidepressivos têm sido monitorados, pois, apresentam intervalos terapêuticos bem estabelecidos, ou seja, a maioria dos pacientes, que apresentam concentrações plasmáticas dentro deste intervalo fixo, tem as desordens psiquiátricas mantidas sob controle e efeitos adversos aceitáveis. Os antidepressivos tricíclicos (ADTs): imipramina, amitriptilina, nortriptilina e desipramina, embora eficazes e ainda muito utilizados, apresentam efeitos adversos, não desejáveis. Os antidepressivos, inibidores seletivos da recaptação de serotonina (ISRSs): citalopram e sertralina, apresentam eficácia clínica comparável aos clássicos ADTs, mas destituídos dos efeitos adversos associados aos mesmos. Os métodos convencionais, empregados no tratamento de amostras biológicas, para análises de antidepressivos por técnicas cromatográficas, têm sido a extração líquido-líquido e extração em fase sólida. A extração sortiva em barra de agitação (SBSE), técnica recente de preparo de amostras para a préconcentração de compostos orgânicos presentes em amostras biológicas, baseiase na extração estática, através do polímero polidimetilsiloxano (PDMS), no qual ocorre a dissolução (sorção, partição) do analito. Neste trabalho, as técnicas SBSE e cromatografia líquida de alta eficiência foram avaliadas para a análise simultânea dos antidepressivos em amostras de plasma para fins de monitorização terapêutica. As condições cromatográficas de análise, assim como as variáveis SBSE de extração (tempo, temperatura, força iônica, pH da matriz) e tempo de dessorção, foram otimizadas, visando adequada sensibilidade analítica. A validação analítica foi realizada segundo normas da ANVISA, em diferentes concentrações plasmáticas, as quais contemplam o intervalo terapêutico. O método SBSE/HPLC padronizado apresentou linearidade na faixa de concentração plasmática de 20 a 1000 ng mL-1, precisão interensaio com coeficientes de variação menor que 14% e recuperação relativa de 83 a 110%. Segundo a validação analítica, a metodologia SBSE/HPLC apresentou linearidade, alta sensibilidade, seletividade e precisão analítica adequadas para a análise dos antidepressivos: imipramina, amitriptilina, nortriptilina, desipramina, citalopram e sertralina, em amostra de plasma, para fins de monitorização terapêutica. / Therapeutic drug monitoring allows individualization of drug dosage assuring its clinical efficacy and at the same time minimizing adverse effects of the drugs prescribed in clinics. The antidepressants have been monitored since they present a very well established therapeutic interval. In this sense, most of the patients whose plasmatic concentrations are ranged at that interval present psychiatric disorders under control and drug adverse effects at bearable levels. Despite tricyclic antidepressants (TCAs) such as imipramine, amitriptyline, nortriptyline and desipramine are highly efficient and widely used, they also present undesirable adverse effects. The antidepressants: citalopram and sertraline, which are selective serotonin reuptake inhibitors (SSRIs), present clinical efficacy comparable to the classic TACs, but with no adverse effects associated to the last ones. Liquid-liquid extraction (LLE) and solid phase extraction (SPE) have been usually employed in biological sample pre-treatment for chromatographic analysis. A new technique named sorptive stir bar extraction (SBSE) for sample pre-concentration of organic compounds from biological samples was recently proposed. This technique is based on static extraction through the polymer polidimetilsiloxane (PDMS), in which analyte sorption occurs. In this work, SBSE and HPLC techniques have been evaluated for out antidepressants simultaneous analysis in plasma samples for therapeutic drug monitoring. The chromatographic conditions of analysis, as well as SBSE parameters (time, temperature, ionic strength, matrix pH, desorption time) have been optimized in order to obtain best analytical sensitivity. Analytical validation was carried out according to the norms established by ANVISA, in different plasmatic concentrations, which represent the therapeutic interval. The SBSE/HPLC method developed showed linearity in a concentration plasmatic ranging from 20 to 1000 ng mL-1, inter assay precision with coefficient of the variation lower than 14%, and relative recovery from 83 a 110%. Based on analytical validation, the SBSE/HPLC methodology showed good linearity, high sensitivity, selectivity and suitable repeatability to the analyzed antidepressants: imipramine, amitriptyline, nortriptyline, desipramine, citalopram and sertraline in plasma samples for therapeutic drug monitoring.
6

Padronização e validação do método extração sortiva em barra de agitação e cromatografia líquida de alta eficiência (SBSE/HPLC) para a determinação de antidepressivos em amostras de plasma / Standardization and validation of the stir-bar sorptive-extraction and high-performance liquid chromatography (SBSE/HPLC) method for antidepressant determination in plasma samples

Silvana Maciel Silva 13 April 2007 (has links)
A monitorização terapêutica permite a individualização do regime de dosagem, assegurando a eficácia clínica e minimizando os efeitos adversos dos fármacos, prescritos na clínica. Os antidepressivos têm sido monitorados, pois, apresentam intervalos terapêuticos bem estabelecidos, ou seja, a maioria dos pacientes, que apresentam concentrações plasmáticas dentro deste intervalo fixo, tem as desordens psiquiátricas mantidas sob controle e efeitos adversos aceitáveis. Os antidepressivos tricíclicos (ADTs): imipramina, amitriptilina, nortriptilina e desipramina, embora eficazes e ainda muito utilizados, apresentam efeitos adversos, não desejáveis. Os antidepressivos, inibidores seletivos da recaptação de serotonina (ISRSs): citalopram e sertralina, apresentam eficácia clínica comparável aos clássicos ADTs, mas destituídos dos efeitos adversos associados aos mesmos. Os métodos convencionais, empregados no tratamento de amostras biológicas, para análises de antidepressivos por técnicas cromatográficas, têm sido a extração líquido-líquido e extração em fase sólida. A extração sortiva em barra de agitação (SBSE), técnica recente de preparo de amostras para a préconcentração de compostos orgânicos presentes em amostras biológicas, baseiase na extração estática, através do polímero polidimetilsiloxano (PDMS), no qual ocorre a dissolução (sorção, partição) do analito. Neste trabalho, as técnicas SBSE e cromatografia líquida de alta eficiência foram avaliadas para a análise simultânea dos antidepressivos em amostras de plasma para fins de monitorização terapêutica. As condições cromatográficas de análise, assim como as variáveis SBSE de extração (tempo, temperatura, força iônica, pH da matriz) e tempo de dessorção, foram otimizadas, visando adequada sensibilidade analítica. A validação analítica foi realizada segundo normas da ANVISA, em diferentes concentrações plasmáticas, as quais contemplam o intervalo terapêutico. O método SBSE/HPLC padronizado apresentou linearidade na faixa de concentração plasmática de 20 a 1000 ng mL-1, precisão interensaio com coeficientes de variação menor que 14% e recuperação relativa de 83 a 110%. Segundo a validação analítica, a metodologia SBSE/HPLC apresentou linearidade, alta sensibilidade, seletividade e precisão analítica adequadas para a análise dos antidepressivos: imipramina, amitriptilina, nortriptilina, desipramina, citalopram e sertralina, em amostra de plasma, para fins de monitorização terapêutica. / Therapeutic drug monitoring allows individualization of drug dosage assuring its clinical efficacy and at the same time minimizing adverse effects of the drugs prescribed in clinics. The antidepressants have been monitored since they present a very well established therapeutic interval. In this sense, most of the patients whose plasmatic concentrations are ranged at that interval present psychiatric disorders under control and drug adverse effects at bearable levels. Despite tricyclic antidepressants (TCAs) such as imipramine, amitriptyline, nortriptyline and desipramine are highly efficient and widely used, they also present undesirable adverse effects. The antidepressants: citalopram and sertraline, which are selective serotonin reuptake inhibitors (SSRIs), present clinical efficacy comparable to the classic TACs, but with no adverse effects associated to the last ones. Liquid-liquid extraction (LLE) and solid phase extraction (SPE) have been usually employed in biological sample pre-treatment for chromatographic analysis. A new technique named sorptive stir bar extraction (SBSE) for sample pre-concentration of organic compounds from biological samples was recently proposed. This technique is based on static extraction through the polymer polidimetilsiloxane (PDMS), in which analyte sorption occurs. In this work, SBSE and HPLC techniques have been evaluated for out antidepressants simultaneous analysis in plasma samples for therapeutic drug monitoring. The chromatographic conditions of analysis, as well as SBSE parameters (time, temperature, ionic strength, matrix pH, desorption time) have been optimized in order to obtain best analytical sensitivity. Analytical validation was carried out according to the norms established by ANVISA, in different plasmatic concentrations, which represent the therapeutic interval. The SBSE/HPLC method developed showed linearity in a concentration plasmatic ranging from 20 to 1000 ng mL-1, inter assay precision with coefficient of the variation lower than 14%, and relative recovery from 83 a 110%. Based on analytical validation, the SBSE/HPLC methodology showed good linearity, high sensitivity, selectivity and suitable repeatability to the analyzed antidepressants: imipramine, amitriptyline, nortriptyline, desipramine, citalopram and sertraline in plasma samples for therapeutic drug monitoring.
7

Characterization of the membrane transporter OATP1A2 activity towards different classes of drugs

Lu, Jennifer 12 1900 (has links)
Les transporteurs membranaires sont des éléments importants dans le devenir, l’efficacité, et la toxicité du médicament. Ils influencent la pharmacocinétique et la pharmacodynamie de ces derniers. Plusieurs interactions médicamenteuses observées cliniquement sont attribuables à la fois aux enzymes responsables du métabolisme des médicaments et aux transporteurs membranaires. Il est connu qu’une variabilité existe entre différents individus dans la réponse à un médicament et les polymorphismes génétiques retrouvés dans les gènes codant pour les transporteurs membranaires peuvent partiellement expliquer cette variabilité. OATP1A2 est un transporteur membranaire exprimé sur des organes importants, comme le cerveau et le rein. Plusieurs médicaments utilisés en clinique sont des substrats d’OATP1A2 et l’expression localisée de ce transporteur suggère un rôle important dans le devenir du médicament. Donc, mon projet de doctorat consistait à caractériser l’activité d’OATP1A2 en relation avec ses substrats et inhibiteurs, et de plus, à évaluer l’impact de différents variants génétiques d’OATP1A2 sur leur transport. Dans le premier article, la rosuvastatine a été utilisée comme substrat-type pour étudier le transport d’OATP1A2. Les expériences ont été menées en introduisant la rosuvastatine en compétition avec différent β-bloqueurs, une classe de médicaments rapportée dans la littérature comme substrats d’OATP1A2. Parmi les β-bloqueurs évalués, le carvédilol était l’inhibiteur le plus puissant. Dans la deuxième partie de l’étude, des médicaments ayant une structure similaire au carvédilol, tels que les antidépresseurs tricycliques, ont été évalués quant à leur potentiel d’inhibition sur OATP1A2. Une relation structure-activité a été définie à l’aide de ces données. Nous avons démontré que des composés tricycliques avec une courte chaîne aliphatique pouvaient inhiber OATP1A2. Dans le deuxième article, OATP1A2 a été étudié en considérant son expression et son rôle au sein de la barrière hémato-encéphalique (BHE). Des études précédentes ont démontré qu’OATP1A2 est exprimé sur la membrane luminale des cellules endothéliales formant la BHE. Nos données démontrent que les triptans, une classe de médicaments couramment utilisées pour traiter la crise migraineuse, sont des substrats d’OATP1A2 et que les composés tricycliques identifiés comme inhibiteurs d’OATP1A2 dans nos études précédentes peuvent inhiber le transport des triptans par OATP1A2. Ces résultats sont importants puisque: 1) il a été suggéré que les triptans peuvent agir au niveau du système nerveux central en se liant aux récepteurs trouvés sur les neurones centraux; 2) comme les triptans sont des molécules hydrophiles, un mécanisme de transport facilité est nécessaire pour qu’ils pénètrent la BHE et OATP1A2 pourrait être l’élément clé; 3) l’inhibition d’OATP1A2 par les composés tricycliques pourrait limiter l’accès des triptans à leur site d’action. Le troisième article caractérise l’activité associée à deux variants génétiques d’OATP1A2 (OATP1A2*2 et *3). Leur capacité à transporter les triptans et leur potentiel d’inhibition par les médicaments tricycliques ont été évalués. Des résultats supplémentaires caractérisant OATP1A2, mais sans liens directs avec les trois articles, seront présentés en annexe. Dans l’ensemble, les résultats présentés dans cette thèse servent à caractériser le transporteur membranaire OATP1A2 en relation avec ses substrats et inhibiteurs, et en fonction de ses variants génétiques. / Drug transporters are important determinants in drug disposition, efficacy, and toxicity. They influence the pharmacokinetics and pharmacodynamics of drugs. Several clinically-observed drug-drug interactions are mediated through drug metabolizing enzymes and drug transporters. It is well known that there is an interindividual variability in the response to medications and polymorphisms found in genes encoding for drug transporters partially account for it. OATP1A2 is a membrane drug transporter expressed on important organs, such as the brain and the kidney. A wide spectrum of drugs used in the clinic are substrates of OATP1A2. Its localisation suggests an essential role in drug disposition. Thus, my PhD project consisted of characterizing the activity of OATP1A2 in regards to its substrates, inhibitors, and different protein variants due to genetic polymorphisms. In the first article, rosuvastatin was used as the probe substrate to study OATP1A2 transport activity. Experiments were conducted by putting rosuvastatin in competition with different β-blockers, a class of drugs known in the literature to be transported by OATP1A2. One of the drugs evaluated, carvedilol, inhibited OATP1A2 with much more potency than the others. In the second part of the study, drugs with a structure similar to carvedilol, such as tricyclic antidepressants, were tested for their potential to inhibit OATP1A2. A structure-activity relationship was defined using the data. It was demonstrated that drugs composed of a tricyclic ring with a short aliphatic amine chain were potent OATP1A2 inhibitors. In the second article presented, OATP1A2 was studied in the context of its localization at the blood-brain barrier (BBB). OATP1A2 expression at the luminal membrane of the endothelial cells making up the BBB was demonstrated in the literature. Our article showed that triptans, a class of commonly used anti-migraine drugs, were OATP1A2 substrates. The tricyclic drugs previously evaluated were shown to potently inhibit triptan transport through OATP1A2. These findings are important for three reasons: 1) it has been postulated that triptans may act at the central nervous system by binding to receptors found on central neurons; 2) as triptans are hydrophilic molecules, a facilitated transport mechanism is required for them to penetrate the BBB and OATP1A2 may be the key player; and 3) the inhibition of OATP1A2 by the tricyclic drugs may limit the entrance of triptans to their site of action. The third article characterized the transport activity of two OATP1A2 protein variants (OATP1A2*2 and *3). Their capacities to transport triptans and their potential of being inhibited by tricyclic drugs were evaluated. Additional data characterizing OATP1A2 but considered out of the scope of the three articles will be presented in appendices. In overall, the central theme of this thesis looks into the characterization of the OATP1A2 membrane drug transporter in regards to its substrates, inhibitors, and proteins variants.
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Effektivitet och säkerhet av tricykliska antidepressiva och selektiva serotonin-återupptagshämmare vid behandling av irritabel tarmsyndrom (IBS)

Muatasim, Mustafa January 2021 (has links)
Irritable bowel syndrome (IBS) is a functional disorder that affects the gastrointestinal tract and especially the large intestine. The pathogenesis of the disease is not fully understood, for that reason there is still no cure and current therapy focuses on symptom relief. The disease manifests itself in the form of abdominal pain, bloating, constipation or diarrhoea. New studies have shown a link between IBS and communication between the central nervous system and the gut. Serotonin and norepinephrine seem to be important for the course of the disease. The purpose of this literature review was to study the efficacy and safety of certain antidepressant preparations belonging to tricyclic antidepressants and selective serotonin reuptake inhibitors in the treatment of IBS. This work focused on the effect of preparations and how tolerable they are with respect to their side effects. Articles presented in this work were found in the PubMed database with the keywords "irritable bowel syndrome", "serotonin reuptake inhibitor", " tricyclic antidepressants ". Amitriptyline 10 mg and imipramine 25 mg provided a statistically significant symptom relief in IBS with diarrhoea (IBS-D) compared to placebo. In addition, tianeptine 12.5 mg 3 times / day, which belongs to the selective serotonin reuptake enhancer (SSRE) group, gave a corresponding symptom relief as amitriptyline 10 mg once / day. The difference between the two was not statistically significant, but the study was open label and non-placebo-controlled, which made it difficult to draw any conclusions. Fluoxetine, which belongs to the selective serotonin reuptake inhibitor (SSRI) group, produced a statistically significant effect compared to placebo in the treatment of constipation IBS (IBS-C). In contrast, paroxetine-CR did not have any statistically significant effect on abdominal pain in IBS-C compared with placebo. However, more patients in the paroxetine group achieved the secondary outcome (clinical global improvement) with scores of 1-2 on the scale Clinical Global Impressions-Improvement (CGI-I). Based on the studies presented in this literature study, it is concluded that a low dose of TCA is an effective and safe treatment for IBS-D while SSRIs are effective and safe in the treatment of IBS-C compared to placebo. / Irritable bowel syndrome (IBS), är funktionella störningar som drabbar gastrointestinalkanalen och framför allt kolon. Patogenesen till sjukdomen är inte helt klarlagd, av den anledningen saknas fortfarande någon botande behandling och dagens terapi fokuserar på symtomlindring. Sjukdomen yttrar sig i form av buksmärta, uppblåsthet, förstoppning eller diarré. Senaste studier har visat en koppling mellan IBS och kommunikation mellan centrala nervsystemet och tarmen. Serotonin och noradrenalin verkar ha betydelse för sjukdomsförlopp. Syftet med detta litteraturarbete var att studera effektivitet och säkerhet för några antidepressiva preparat som tillhör tricykliska antidepressiva och selektiva serotonin återupptagshämmare vid behandling av IBS. Detta arbete fokuserade på effekten av preparaten och hur tolererbara de är med avseende på deras biverkningar. Artiklar som presenteras i detta arbete söktes i databasen Pubmed med sökord ”irritable bowel syndrome”, ”serotonin reuptake inhibitors”, ” tricyclic antidepressants”. Amitriptylin 10mg och imipramin 25mg gav en statistiskt signifikant symtomlindring vid IBS med diarré (IBS-D) jämfört med placebo. Dessutom gav tianeptin 12,5mg 3 gånger/dag, som tillhör läkemedelsgruppen selektiv serotonin återupptagsenhancer (SSRE), en likvärdig symtomlindring som amitriptylin 10mg en gång/dag. Skillnaden mellan de två var inte statistiskt signifikant, däremot var studien openlabel och icke-placebokontrollerad vilket gör det svårt att dra någon slutsats. Fluoxetin, som tillhör läkemedelsgruppen selektiva serotonin återupptagshämmare SSRI, gav en statistiskt signifikant effekt jämfört med placebo vid behandling av IBS med förstoppning (IBS-C). Däremot gav paroxetin-CR ingen statistiskt signifikant effekt på buksmärta vid IBS-C jämfört med placebo, dock uppnådde fler i paroxetingruppen den sekundära utfallsvariabeln (global klinisk förbättring) och fick poäng mellan 1 – 2 på skalan Clinical Global Impressions-Improvement (CGI-I).  Baserat på studierna som presenteras i denna litteraturstudie dras slutsatsen att en låg dos TCA är en effektiv och säker behandling vid IBS-D medan SSRI är effektiva och säkra vid behandling av IBS-C jämfört med placebo.

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