Obtenção do pró-fármaco recíproco de isoniazida e metronidazol potencialmente ativo contra Mycobacterium tuberculosis

A tuberculose é uma doença que já atingiu milhares de pessoas no mundo e ainda hoje representa uma ameaça à saúde humana, principalmente a partir da descoberta do vírus HIV. Os fármacos disponíveis no mercado não têm suprimido as necessidades, pois exigem longos períodos de tratamento. Este trabalho teve como objetivo o planejamento e a síntese de um novo composto potencialmente ativo para Mycobacterium tuberculosis na forma latente. O planejamento levou em consideração o princípio da latenciação para a obtenção de um pró-fármaco recíproco derivado de isoniazida e metronidazol. O metronidazol, devido à sua ação em bactérias anaeróbicas poderia apresentar atividade nos bacilos que possivelmente sobrevivam durante o processo de necrose caseosa. A obtenção do pró-fármaco foi realizada através da transformação funcional do metronidazol e posterior acoplamento com isoniazida. O trabalho descreve alguns procedimentos e dificuldades encontradas para obtenção do pró-fármaco. Os resultados sugerem a formação do produto, porém, análises de identificação são necessárias para a confirmação

Identificação molecular e genotipagem pela técnica de Spoligotyping de Mycobacterium tuberculosis isolado da população indígena e não-indígena no Mato Grosso do Sul (MS)

O presente trabalho baseou-se na análise de amostras de isolados de M. tuberculosis provenientes da população indígena e não indígena do Mato Grosso do Sul. As análises foram feitas basicamente por três técnicas de Biologia Molecular: PCR-IS6110 e PRA (para identificação) e Spoligotyping (para genotipagem), ressaltando que somente as amostras negativas para PCR-IS6110 foram submetidas ao PRA. Os objetivos do estudo eram: confirmar por técnicas moleculares de PCR e de PRA a identificação do complexo M. tuberculosis e de outras micobactérias, após o descongelamento e cultivo, analisar a incidência de isolados de M. tuberculosis da região do Mato Grosso do Sul que não tem o IS6110, avaliar a incidência de outras micobactérias entre a população indígena e não indígena do Mato Grosso do Sul, agrupar em famílias, por similaridade epidemiológica os isolados de M. tuberculosis procedentes da população indígena e não indígena com TB e avaliar a presença efetiva de grupos genéticos predominantes; Pela técnica de PCR-IS6110, analisamos um total de 119 isolados clínicos, sendo que apenas 6 apresentaram negatividade, sendo assim submetidos à técnica do PRA. Feito isso, também apresentaram resultado positivo para CMTB, nos permitindo concluir que essas técnicas podem se tornar ferramentas de grande valia no diagnóstico rápido da TB. Pela técnica de genotipagem do Spoligotyping foram analisadas 97 amostras e foi constatado um maciço predomínio da família LAM, principalmente da subfamília LAM 9, representados por 4 SITs, sendo SIT 42 com 44 isolados e SITs 177, 1337 e 1075 com respectivamente 4, 2 e 1 isolados cada (essa subfamília representou 52,6% do total de isolados). Outras famílias, tais como T, H e U também estiveram presentes no estudo em menores proporções

Esteroide e Triterpenos de espécies de Qualea: Bioatividade sobre Mycobacterium tuberculosis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Esteroide e Triterpenos de espécies de Qualea: bioatividade sobre Mycobacterium tuberculosis

The chloroform extract of bark of the tropical tree Qualea parviflora (Vochysiaceae) was fractionated by column chromatography on silica gel, yielding triterpenes (lupeol, lupenone, betulin, epi-betulinic acid and friedelin) and a steroid (β-sitosterol). β-sitosterol, lupenone and lupeol were also identified in Q. grandiflora and Q. multiflora, while friedelin was detected only in Q. Multiflora, by means of gas chromatography-mass spectrometry. The anti-Mycobacterium tuberculosis activity of the chloroform extract and isolated compounds was assayed by MABA and MIC values ranged from 250.0 to 31.2 µg/mL. This study is the first to investigate the chemistry and antitubercular activity of apolar compounds from Qualea species.

Paepalanthus spp: antimycobacterial activity of extracts, methoxylated flavonoids and naphthopyranone fractions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determinação molecular da viabilidade do Mycobacterium leprae: uma comparação com outras abordagens metodológicas

Pós-graduação em Doenças Tropicais - FMB

Diversidade clínica, epidemiológica e Genética do Mycobacterium tuberculosis na região Noroeste paulista

Pós-graduação em Genética - IBILCE

Mycobacterium marinum infection: a case report

The infection by Mycobacterium marinum in humans is relatively uncommon. When it occurs, it mainly affects the skin, usually with a chronic, indolent and benign evolution. The diagnosis requires a high index of suspicion, and a significant delay may be observed between the first symptoms to the final diagnosis. This present case reports a M. marinum infection in an immunocompetent patient that had a chronic undiagnosed injury on the dominant hand for at least five years. The patient had several medical consultations, without proper suspicion, hampering adequate diagnostic investigation. Histopathology detected tuberculoid granulomas, but showed no acid-fast bacilli. The culture in appropriate medium and the polymerase chain reaction-restriction enzyme analysis (PRA)-hsp65 confirmed the diagnosis. Treatment with clarithromycin (1 g/day) for three months was effective. Although uncommon, this infection is a contact zoonosis. Therefore, it is important for clinicians to be aware of this diagnosis and properly guide preventable measures to professionals that are in risk group.

Ruthenium(II) complexes with hydroxypyridinecarboxylates: screening potential metallodrugs against Mycobacterium tuberculosis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bioactivity of pyridine-2-thiolato-1-oxide metal complexes: Bi(III), Fe(III) and Ga(III) complexes as potent anti-Mycobacterium tuberculosis prospective agents

In the search for new therapeutic tools against tuberculosis and to further address the therapeutic potential of pyridine-2-thiol 1-oxide (Hmpo) metal complexes, two new octahedral [M(III)(mpo)3] complexes, with M = Ga or Bi, were synthesized and characterized in the solid state and in solution. Attempts to crystallize [Ga(III)(mpo)3] in CH2Cl2 led to single crystals of the reaction product [GaCl(mpo)2], where the gallium(III) ion is in a square basis pyramidal environment, trans-coordinated at the basis to two pyridine-2-thiolato 1-oxide anions acting as bidentate ligands through their oxygen and sulfur atoms. The biological activity of the new [M(III)(mpo)3] complexes together with that of the previously reported Fe(III) analogous compound and the pyridine-2-thiol 1-oxide sodium salt (Na mpo) was evaluated on Mycobacterium tuberculosis. The compounds showed excellent activity, both in the standard strain H37Rv ATCC 27294 (pan-susceptible) and in five clinical isolates that are resistant to the standard first-line anti-tuberculosis drugs isoniazid and rifampicin. These pyridine-2-thiol 1-oxide derivatives are promising compounds for the treatment of resistant tuberculosis.

Vanadium complexes with hydrazone or thiosemicarbazone ligands as potential anti-mycobacterium tuberculosis agents

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Thiophenecarboxamide derivatives activated by EthA kill mycobacterium tuberculosis by inhibiting the CTP synthetase PyrG

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo da diversidade genética do MycobacteriUm leprae em pacientes com hanseníase no município de Rondonópolis (MT): uma contribuição para o melhor entendimento da sua transmissão

Pós-graduação em Doenças Tropicais - FMB

The Mycobacterium leprae hsp65 displays proteolytic activity. Mutagenesis studies indicate that the M. leprae hsp65 Proteolytic activity is catalytically related to the HslVU protease?

The present study reports, for the first time, that the recombinant hsp65 from Mycobacterium leprae (chaperonin 2) displays a proteolytic activity toward oligopeptides. The M. leprae hsp65 proteolytic activity revealed a trypsin-like specificity toward quenched fluorescence peptides derived from dynorphins. When other peptide substrates were used (β-endorphin, neurotensin, and angiotensin I), the predominant peptide bond cleavages also involved basic amino acids in P 1, although, to a minor extent, the hydrolysis involving hydrophobic and neutral amino acids (G and F) was also observed. The amino acid sequence alignment of the M. leprae hsp65 with Escherichia coli Hs1VU protease suggested two putative threonine catalytic groups, one in the N-domain (T 136, K 168, and Y 264) and the other in the C-domain (T 375, K 409, and S 502). Mutagenesis studies showed that the replacement of K 409 by A caused a complete loss of the proteolytic activity, whereas the mutation of K 168 to A resulted in a 25% loss. These results strongly suggest that the amino acid residues T 375, K 409, and S 502 at the C-domain form the catalytic group that carries out the main proteolytic activity of the M. leprae hsp65. The possible pathophysiological implications of the proteolytic activity of the M. leprae hsp65 are now under investigation in our laboratory.

Evaluation of the anti-mycobacterium tuberculosis activity and in vivo acute toxicity of annona sylvatic

Background The recent emergence of extensively multidrug-resistant Mycobacterium tuberculosis strains has further complicated the control of tuberculosis. There is an urgent need for the development of new molecular candidates antitubercular drugs. Medicinal plants have been an excellent source of leads for the development of drugs. The aim of this study was to evaluate the in vitro activity of 28 alcoholic extracts and essential oils of native and exotic Brazilian plants against Mycobacterium tuberculosis and to further study these extracts through chemical fractionation, the isolation of their constituents, and an evaluation of the in vivo acute toxicity of the active extracts. To the best of our knowledge this is the first chemical characterization, antituberculosis activity and acute toxicity evaluation of Annona sylvatica. Methods The anti-mycobacterial activity of these extracts and their constituent compounds was evaluated using the resazurin reduction microtiter assay (REMA). To investigate the acute toxicity of these extracts in vivo, female Swiss mice were treated with the extracts at doses of 500, 1000 and 2000 mg · kg-1 of body weight. The extracts were characterized by LC-MS, and the constituents were isolated and identified by chromatographic analysis of spectroscopic data. Results Of the 28 extracts, the methanol extract obtained from the leaves of Annona sylvatica showed anti-mycobacterial activity with an minimal inhibitory concentration (MIC) of 184.33 μg/mL, and the ethyl acetate fraction (EAF) resulting from liquid-liquid partitioning of the A. sylvatica extract showed an MIC of 115.2 μg/mL. The characterization of this extract by LC-MS identified flavonoids and acetogenins as its main constituents. The phytochemical study of the A. sylvatica EAF resulted in the isolation of quercetin, luteolin, and almunequin. Conclusions Among the compounds isolated from the EAF, luteolin and almunequin were the most promising, with MICs of 236.8 μg/mL (827.28 μM) and 209.9 μg/mL (328.48 μM), respectively. The acute administration of the EAF fraction in doses of 500, 1000, and 2000 mg · kg-1 of body weight did not cause signs of toxicity in the treated animals.