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The three thiopurine drugs azathioprine (AZA), 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG) are used to treat several diseases, including inflammatory bowel disease (IBD). They are pro-drugs and are believed to act through the formation of thioguanine nucleotides (TGNs). Other important metabolites are the methylthioinosine nucleotides (meTINs). These metabolites are active in the white blood cells (WBCs).Most patients respond well to the thiopurine drugs but up to a third have to modify or discontinue their treatment due to adverse events or a lack of therapeutic effects. This could be caused by inter-patient variability in the metabolism of the drugs. Therapeutic drug monitoring (TDM) of thiopurine nucleotides in red blood cells (RBCs) is used to guide treatment. Current routine assays measure the nucleotides after hydrolysation to nucleic bases and are therefore unable to distinguish between mono-, di-, and triphosphates. Recently it was shown that these assays failed to predict the clinical outcome in about 40% of the patients. It has been suggested that measuring thioguanosine triphosphate (TGTP) (believed to be the most active of the TGNs) separately might increase the clinical value.An assay suitable for measuring thioguanosine mono- (TGMP) and diphosphate (TGDP) and TGTP, as well as methylthioinosine mono- (meTIMP), di- (meTIDP) and triphosphate (meTITP) separately in RBCs in clinical samples has been developed. In clinical studies of 82 IBD patients, we found no correlation between the thiopurine dose and metabolite levels in RBCs, thus illustrating the importance of metabolite measurements in the TDM of thiopurines.The TGN peak measured by the routine assay during TDM of patients treated with thiopurines consisted of TGTP and TGDP with a small contribution from TGMP. The meTIN also consisted of mono-, di- and triphosphates, but in different proportions, indicating differences in the formation. The inter-individual differences in nucleotide distribution were very small and a strong correlation between the different nucleotides and their respective sums was observed. As a consequence, measuring the mono-, di- and triphosphates separately was not beneficial in predicting remission, which was confirmed by the results from the clinical study.Further research into the metabolism and mode of action of thiopurine drugs is needed to understand the inter-patient variability in response and metabolite formation. An assay suitable for such studies, measuring TGNs and meTINs in cultured cells, has also been developed.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Les médicaments thiopuriniques que sont l'azathioprine, la 6-mercaptopurine et la 6-thioguanine sont utilisés depuis des décennies pour leurs propriétés cytotoxiques et immunosuppressives dans le traitement de certaines leucémies, de maladies inflammatoires chroniques ou auto-immunes ainsi que dans la prévention du rejet de greffe. Certains patients, traités par des doses conventionnelles de ces molécules, développent cependant des effets indésirables parfois très sévères. Le déficit d'activité, d'origine génétique, de la thiopurine S-méthyltransférase (TPMT), enzyme impliquée dans le métabolisme des thiopurines, constitue l'un des facteurs majeurs de la myélotoxicité de ces médicaments. La détermination du phénotype TPMT par génotypage, qui est une mesure préventive avant l'introduction d'un traitement thiopurinique, repose sur l'identification des mutations inactivatrices les plus fréquentes du gène TPMT. Une partie de ce travail a consisté en l'analyse fonctionnelle de quatre variants alléliques rares du gène TPMT dans un système d'expression hétérologue, la levure S. cerevisiae. Le caractère non-fonctionnel de deux d'entre eux a ainsi été démontré. Cependant, le déficit d'activité de la TPMT ne permet d'expliquer qu'environ 30 % des cas de myélotoxicité sous thiopurines, ce qui laisse supposer l'existence d'autres anomalies génétiques affectant d'autres gènes impliqués dans la réponse de l'organisme à ces molécules. Ainsi, nous avons étudié le polymorphisme génétique de deux autres protéines candidates, celui de l'inosine monophosphate déshydrogénase de type 2 (IMPDH2), enzyme-clé de la formation des métabolites actifs des thiopurines, et celui de la RhoGTPase RAC1, qui est l'une des cibles pharmacologiques de ces molécules. Certains des polymorphismes que nous avons identifiés dans ces deux gènes semblent affecter in vitro l'expression et/ou l'activité de ces protéines et pourraient, par conséquent, contribuer aux variations inter-individuelles de réponse aux thiopurines

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-04-26T19:22:03Z No. of bitstreams: 1 robertacristinanovaesreiscorrales.pdf: 3333393 bytes, checksum: a90614981046f5f6e0791845afd8c1fd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-13T12:05:49Z (GMT) No. of bitstreams: 1 robertacristinanovaesreiscorrales.pdf: 3333393 bytes, checksum: a90614981046f5f6e0791845afd8c1fd (MD5) / Made available in DSpace on 2017-05-13T12:05:49Z (GMT). No. of bitstreams: 1 robertacristinanovaesreiscorrales.pdf: 3333393 bytes, checksum: a90614981046f5f6e0791845afd8c1fd (MD5) Previous issue date: 2011-06-17 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A tese de doutorado intitulada Síntese e Avaliação Biológica de Derivados de 6-Mercaptopurina, Carboidratos e Aminoálcoois está apresentada em três capítulos que descrevem a síntese e caracterização de compostos com potencial atividade antiparasitária (Leishmania, Plasmodium berghei), antibacteriana (bactérias Gram positiva e negativa, Mycobacterium tuberculosis) e em macrófagos peritoneais de mamíferos. Foram obtidos 53 compostos neste trabalho, sendo 30 inéditos, a saber: no capitulo 1 foi descrita a síntese de 27 compostos, sendo 14 derivados inéditos de 6mercaptopurina (6-MP); no capítulo 2 foi descrita a síntese de 14 compostos, sendo 6 derivados inéditos da D-glicose e 1 derivado inédito da D-ribonolactona; no capítulo 3 foi descrita a síntese de 14 compostos, sendo 9 aminoálcoois inéditos. O primeiro capítulo mostra a síntese de derivados de 6-MP contendo 1,2,3-triazol e derivados de esteróides. Os derivados triazólicos de 6-MP foram obtidos através de uma reação de cicloadição 1,3-dipolar tipo “click” usando um alcino terminal e um grupo azido. Os derivados de 6-MP contendo esteróides, sem o espaçador triazólico, foram obtidos através de uma reação de substituição nucleofílica entre o sal de 6-MP e mesilatos do ácido cólico e do ácido desoxicólico. Dentre os compostos submetidos à avaliação biológica, os derivados de 6-MP conjugados com esteróides apresentaram melhor atividade em Leishmania e a maioria apresentou importante atividade em P. berghei. Nenhum composto testado apresentou citotoxicidade in vitro para macrófagos peritoneais de camundongos até a máxima concentração de 48 µg/mL. O segundo capítulo mostra a síntese e caracterização de derivados da D-glicose contendo 1,2,3-triazol, obtidos através de reação tipo “click” e de derivados da D-gliconolactona e D-ribonolactona. Apesar dos compostos testados não terem apresentado atividade antiparasitária e antibacteriana efetiva, nenhum apresentou toxidez para os macrófagos de mamíferos. O terceiro capítulo descreve a síntese e caracterização de derivados aminoálcoois aromáticos com variada extensão de cadeia e de função química e apresentaram importante atividade biológica, principalmente em L. major. As estruturas dos produtos obtidos foram elucidadas pelos seus espectros na região do infravermelho, Ressonância Magnética Nuclear de 1H e 13C, Mapa de contornos homonuclear COSY, faixa de fusão e espectros de massas de alta resolução. / The doctoral thesis entitled Synthesis and Biological Evaluation of Derivatives of 6-Mercaptopurine, Carbohydrates and Aminoalcohol is presented in three chapters that describe the synthesis and characterization of compounds with potential antiparasitic activity (Leishmania, Plasmodium berghei), antibacterial (bacteria Gram positive and negative, Mycobacterium tuberculosis) and peritoneal macrophages of mammals. 53 compounds were obtained in this work, with 30 firsts, namely: Chapter 1 was described in the synthesis of compounds 27, 14 novel derivatives of 6-mercaptopurine (6MP), was described in Chapter 2 the synthesis of compounds 14, 6 being derived from unpublished 1 D-glucose and derived novel D-ribonolactona, was described in Chapter 3 the synthesis of compounds 14, 9 amino unpublished. The first chapter shows the synthesis of derivatives of 6-MP containing 1,2,3triazole derivatives and steroids. The triazole derivatives of 6-MP were obtained by a reaction of type 1,3-dipolar cycloaddition "click" using a terminal alkyne and an azide group. Derivatives of 6-MP containing steroids, without the spacer triazole, was obtained through a nucleophilic substitution reaction between the salt of 6-MP and mesylates cholic acid and deoxycholic acid. Among the compounds subjected to biological evaluation, derivatives of 6-MP in conjunction with steroids showed better activity in Leishmania and most showed a significant activity in P. berghei. No compound tested showed cytotoxicity in vitro for mouse peritoneal macrophages to g / mL.µthe maximum concentration of 48 µg/mL. The second chapter shows the synthesis and characterization of D-glucose derivatives containing 1,2,3-triazole, obtained by reaction type "click" derivatives of Dgliconolactona and D-ribonolactona. Although the compounds tested did not show effective antibacterial and antiparasitic activity, showed no toxicity to mammalian macrophages. The third chapter describes the synthesis and characterization of aromatic amino derivatives with varied chain length and chemical function and had significant biological activity, especially in L. Major. The structures of the products obtained were elucidated by their spectra in the infrared, 1H NMR and 13C, homonuclear COSY contour map, melting point and mass spectra with high resolution.

6-mercaptopurine was joined by diazotation and copulation reactions on Iontosorb AV. Presence of thiol groups in modified resin was showed by infrared spectrometry. Amount of thiol groups was determined by iodometric titration. Resin gel was preparated from modified resin and agarose and both of them were tested for mercury determination by DGT technique.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-09-15T12:09:54Z No. of bitstreams: 1 nicollibellottidesouza.pdf: 1508500 bytes, checksum: 7150363e1a046cd4741555cb142f6f21 (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2016-09-26T20:18:43Z (GMT) No. of bitstreams: 1 nicollibellottidesouza.pdf: 1508500 bytes, checksum: 7150363e1a046cd4741555cb142f6f21 (MD5) / Made available in DSpace on 2016-09-26T20:18:43Z (GMT). No. of bitstreams: 1 nicollibellottidesouza.pdf: 1508500 bytes, checksum: 7150363e1a046cd4741555cb142f6f21 (MD5) Previous issue date: 2011-02-22 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A malária é causada por protozoários do gênero Plasmodium e é responsável por 250 milhões de casos e 1 milhão de mortes anualmente. Um dos principais empecilhos para o controle da doença é o desenvolvimento de resistência do parasito aos fármacos comumente usados, o que torna urgente a pesquisa por novos antimaláricos. Nesse contexto, análogos de cloroquina acoplados a 6-mercaptopurina e a alquil aminas e complexos de platina foram avaliados quanto a atividade antimalárica utilizando o teste supressivo descrito por Peters em modelo murino de infecção por Plasmodium berghei NK65. Tais análogos exibiram altos valores de supressão da parasitemia, entre 60% e 94% em comparação com o controle não tradado. Considerando o papel imunossupressor de derivados de purina, o análogo de cloroquina acoplado a 6-mercaptopurina MPQUI foi avaliado quanto a aspectos imunológicos (contagem de leucócitos específicos, dosagem de TNF-α e IL-10), não interferindo na resposta imune tendo como base os parâmetros analisados. Portanto, esses análogos devem ser objetos de futuras pesquisas, podendo fornecer novos antimaláricos, já que apresentaram-se promissores e não influenciaram a resposta imune nos parâmetros analisados. / Malaria is caused by protozoan parasites of the genus Plasmodium and is responsible for 250 million cases and 1 million deaths annually. One of the main obstacles for the disease control is the development of resistance by the parasite to the commonly used antimalarials, what makes the research for new ones urgent. In this context, chloroquine analogs attached to 6-mercaptopurine and to alkyl-amines and platinum complexes were evaluated for their antimalarial activity using the 4-day suppressive test described by Peters which was carried out in mice infected with Plasmodium berghei NK65. These analogs exhibited high values of parasitemia suppression, which ranged from 60% to 94% in comparison to untreated control. Considering the immune suppressor role of purine derivates, the chloroquine analog attached to 6-mercaptopurine MPQUI was evaluated for immunological aspects (specific leukocytes count, TNF-α and IL-10 measurements in sera of mice), revealing no interference in the immune response considering these parameters. Therefore, these analogs may be objects of further research, aiming at new antimalarials, since they were shown to be promising and did not influence the immune response in the parameters analyzed.