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1.
Nanoscale ; 13(31): 13225-13230, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34477730

RESUMO

We present a non-immunogenic, injectable, low molecular weight, amphiphilic hydrogel-based drug delivery system (TB-Gel) that can entrap a cocktail of four front-line antitubercular drugs, isoniazid, rifampicin, pyrazinamide, and ethambutol. We showed that TB-Gel is more effective than oral delivery of the combination of four drugs in reducing the mycobacterial infection in mice. Results show that half the dose of chemotherapeutic drugs is sufficient to achieve a comparable therapeutic effect to that of oral delivery.


Assuntos
Antituberculosos , Hidrogéis , Animais , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Etambutol , Isoniazida , Camundongos , Pirazinamida
2.
Pan Afr Med J ; 39: 97, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34466199

RESUMO

Introduction: an estimated 25% of the world population is infected with Mycobacterium tuberculosis. In 2017, new tuberculosis cases were estimated at 10 million, while 1.6 million tuberculosis related deaths were recorded, 25% residing in Africa. Treatment outcomes of multi drug resistant Tuberculosis patients in Zimbabwe has been well documented but the role of bacteriological monitoring on treatment outcomes has not been systematically evaluated. The objective of the study was to determine the role of bacteriological monitoring using culture and drug susceptibility tests on treatment outcomes among patients with multi drug resistant tuberculosis. Methods: a retrospective, secondary data analysis was conducted using routinely collected data of patients with multi drug resistant TB in Zimbabwe. Frequencies were used to summarize categorical variables and a generalized linear model with a log-link function and a Poisson distribution was used to assess factors associated with unfavourable outcomes. The level of significance was set at P-Value<0.05. Results: about the study collected data from 473 records of patients with an average age of 36.35 years. Forty-nine percent (49%) were male and 51% were female. Results showed that when a patient has baseline culture result missing, has no culture conversion result, regardless of having a follow up culture and drug susceptibility test result, the risk of developing unfavourable outcomes increase by 3.9 times compared to a patient who has received all the three (3) bacteriological monitoring tests. Conclusion: results highlights the need for consistent bacteriological monitoring of patients to avert unfavourable treatment outcomes.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Estudos Retrospectivos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto Jovem , Zimbábue/epidemiologia
3.
J Infect Chemother ; 27(11): 1578-1583, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34244055

RESUMO

INTRODUCTION: Rifampicin (RIF) is one of the most effective anti-tuberculosis first-line drugs prescribed along with isoniazid. However, the emergence of RIF resistance Mycobacterium tuberculosis (MTB) isolates is a major issue towards tuberculosis (TB) control program in high MDR TB-burdened countries including Pakistan. Molecular data behind phenotypic resistance is essential for better management of RIF resistance which has been linked with mutations in rpoB gene. Since molecular studies on RIF resistance is limited in Pakistan, the current study was aimed to investigate the molecular data of mutations in rpoB gene behind phenotypic RIF resistance isolates in Pakistan. METHOD: A total of 322 phenotypically RIF-resistant isolates were randomly selected from National TB Reference Laboratory, Pakistan for sequencing while 380 RIF resistance whole-genome sequencing (WGS) of Pakistani isolates (BioProject PRJEB25972), were also analyzed for rpoB mutations. RESULT: Among the 702 RIF resistance samples, 675 (96.1%) isolates harbored mutations in rpoB in which 663 (94.4%) were detected within the Rifampicin Resistance Determining Region (RRDR) also known as a mutation hot spot region, including three novel. Among these mutations, 657 (97.3%) were substitutions including 603 (89.3%) single nucleotide polymorphism, 49 (7.25%) double and five (0.8%) triple. About 94.4% of Phenotypic RIF resistance strains, exhibited mutations in RRDR, which were also detectable by GeneXpert. CONCLUSION: Mutations in the RRDR region of rpoB is a major mechanism of RIF resistance in MTB circulating isolates in Pakistan. Molecular detection of drug resistance is a faster and better approach than phenotypic drug susceptibility testing to reduce the time for transmission of RIF resistance strains in population. Such insights will inform the deployment of anti-TB drug regimens and disease control tools and strategies in high burden settings, such as Pakistan.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , RNA Polimerases Dirigidas por DNA/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Paquistão , Rifampina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
4.
Tuberk Toraks ; 69(2): 279-284, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34256520

RESUMO

Methylene blue is used for bacterial staining in microbiology and as an antidote drug in medicine. In this study, we aimed to investigate the antimicrobial effects of methylene blue against Mycobacterium tuberculosis complex clinical isolates. Seventeen stored M. tuberculosis complex clinical isolates were included in the study. The isolates were inoculated into Mycobacteria Growth Indicator Tubes and incubated in Automated Mycobacterial Detection System. Mycobacteria Growth Indicator tubes containing methylene blue at critical concentrations of 0.2, 2, 20, 1000 µg ml-1 and control tube were prepared. Antimicrobial susceptibility testing was performed using Automated Mycobacterial Detection System which is gold standard for second line anti-tuberculosis drug testing. At the end of the study, six clinical isolates were susceptible to methylene blue at all critical concentrations. Five isolates were susceptible to only 1000 µg ml-1 methylene blue. Three isolates were susceptible to 1000 and 20 µg ml-1 methylene blue. Susceptibility rate was found as 94% when the critical proportion was accepted 400 GU (1/100 of control). Significant relationship was observed between the administered methylene blue concentrations and bacterial survival rate in statistical analysis. We conclude that methylene blue may become a potential anti-tuberculosis agent due to its well-known side effects and dosing regimens.


Assuntos
Antituberculosos/farmacologia , Azul de Metileno/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/isolamento & purificação
5.
J Pharm Biomed Anal ; 203: 114223, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34214766

RESUMO

Isoniazid (INH) is the first-line anti-tubercular drug that is used both for the prophylaxis as well as the treatment of tuberculosis (TB). The patients with TB are more vulnerable to secondary infections and other health complications, hence, they are usually administered a cocktail of drugs. This increases the likelihood of drug-drug interactions (DDIs). INH is clinically proven to interact with drugs like phenytoin, carbamazepine, diazepam, triazolam, acetaminophen, etc. Most of such clinical observations have been supported by in vitro inhibition studies involving INH and cytochrome P450 (CYP) enzymes. A few published in vitro studies have explored the CYP2E1 inhibition potential of INH to explain its interactions with acetaminophen and other CY2E1 substrates, such as chlorzoxazone, but none of them were able to demonstrate any significant inhibition of the enzyme by the drug. It was reported that metabolites of INH, such as acetylhydrazine and hydrazine, were bioactivated by CYP2E1, highlighting that perhaps the drug metabolites were responsible for the mechanism based inhibition (MBI) of the enzyme. Therefore, the purpose of this investigation was to explore CYP2E1 enzyme inhibition potential of INH and its four major metabolites, viz., acetylisoniazid, isonicotinic acid, acetylhydrazine and hydrazine, using human liver microsomes (HLM). Additionally, we determined the fraction unbound in microsomal incubation (fumic) for all the five compounds using equilibrium dialysis assay. We observed that INH and its metabolites had lower propensity for microsomal binding, and the metabolites also lacked the potential to inhibit CYP2E1 enzyme, either by direct inhibition or through MBI. This suggests involvement of some other mechanism to explain interactions of INH with CY2E1 substrates, signifying need of further exploration.


Assuntos
Citocromo P-450 CYP2E1 , Isoniazida , Antituberculosos/farmacologia , Cromatografia Líquida , Humanos , Isoniazida/farmacologia , Microssomos Hepáticos , Espectrometria de Massas em Tandem
6.
Molecules ; 26(14)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34299475

RESUMO

A series of novel riminophenazine derivatives, having ionizable alkyl substituents at N-5 and a variety of substituents on the C-3 imino nitrogen, at C-8 and on the pendant aryl group, have been designed and synthesized. Preliminary investigations into the relationship between lipophilicity, redox potential, and antimycobacterial activity were conducted, using the in vitro activity against Mycobacterium tuberculosis H37Rv, mammalian cytotoxicity, and the redox potential of the compounds determined by cyclic voltammetry as measures. Results revealed an activity "cliff" associated with C-8 substitution (10l and 10m) that, along with defined redox activity, point to a new class of riminophenazines as potential anti-tuberculosis agents having reasonable activity (MIC99 ~1 µM).


Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Desenho de Fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Fenazinas/química , Técnicas Eletroquímicas , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
7.
Int J Infect Dis ; 109: 294-303, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34273514

RESUMO

OBJECTIVE: We conducted a cross-sectional study in the five administrative regions of Northern Ghana to determine the diversity of Mycobacterium tuberculosis complex (MTBC) sub/lineages and their susceptibility to isoniazid (INH) and rifampicin (RIF). METHODS: Sputum specimens were collected and cultured from 566 pulmonary tuberculosis patients reporting to 17 health facilities from 2015 to 2019. Mycobacterial isolates obtained from solid cultures were confirmed as members of the MTBC by PCR amplification of IS6110 and rpoß and assigned lineages and sub-lineages using spoligotyping. RESULTS: Of 294 mycobacterial isolates recovered, MTBC species identified were: M. tuberculosis sensu stricto (Mtbss) 241 (82.0%), M. africanum 41 (13.9%) and M. bovis four (1.4%) with eight (2.7%) unidentified. The human-adapted lineages (L) identified (N=279) were L1 (8/279, 2.9%), L2 (15/279, 5.4%), L3 (7/279, 2.5%), L4 (208/279, 74.5%), L5 (13/279, 4.7%) and L6 (28/279, 10.0%) with three unidentified lineages. Among the 208 L4, the dominant sub-lineages in the region were the Cameroon 120/208 (57.7%) and Ghana 50/208 (24.0%). We found 4.4% (13/294) and 0.7% (2/294) of the patients infected with MTBC isolates resistant to INH only and RIF only, respectively, with 2.4% (7/294) being infected with MDR strains. Whereas L6 was associated with the elderly, we identified that the Ghana sub-lineage of L4 was associated with both INH and MDR (p<0.05), making them important TB pathogens in Northern Ghana and a growing public health concern.


Assuntos
Mycobacterium tuberculosis , Preparações Farmacêuticas , Tuberculose Resistente a Múltiplos Medicamentos , Idoso , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Estudos Transversais , Genótipo , Gana/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
8.
ACS Infect Dis ; 7(8): 2437-2444, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34196521

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is a major global health concern given the increase in multiple forms of drug-resistant TB. This underscores the importance of a continuous pipeline of new anti-TB agents. Drug repurposing has shown promise in expanding the therapeutic options for TB chemotherapy. Fusidic acid (FA), a natural product-derived antibiotic, is one such candidate for repurposing. The present study aimed to understand the mechanism of action of FA and its selected analogs in M. tuberculosis. By using chemical biology and genetics, we identified elongation factor G as the target of FA in M. tuberculosis. We showed essentiality of its encoding gene fusA1 in M. tuberculosis by demonstrating that the transcriptional silencing of fusA1 is bactericidal in vitro and in macrophages. Thus, this work validated a novel drug target FusA1 in M. tuberculosis.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Antituberculosos/farmacologia , Ácido Fusídico/farmacologia , Genes Essenciais , Humanos , Mycobacterium tuberculosis/genética , Tuberculose/tratamento farmacológico
9.
ACS Infect Dis ; 7(8): 2492-2507, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34279904

RESUMO

SQ109 is a drug candidate for the treatment of tuberculosis (TB). It is thought to target primarily the protein MmpL3 in Mycobacterium tuberculosis, but it also inhibits the growth of some other bacteria. SQ109 is metabolized by the liver, and it has been proposed that some of its metabolites might be responsible for its activity against TB. Here, we synthesized six potential P450 metabolites of SQ109 and used these as well as 10 other likely metabolites as standards in a mass spectrometry study of M. tuberculosis-infected rabbits treated with SQ109, in addition to testing all 16 putative metabolites for antibacterial activity. We found that there were just two major metabolites in lung tissue: a hydroxy-adamantyl analog of SQ109 and N'-adamantylethylenediamine. Neither of these, or the other potential metabolites tested, inhibited the growth of M. tuberculosis or of M. smegmatis, Bacillus subtilis, or E. coli, making it unlikely that an SQ109 metabolite contributes to its antibacterial activity. In the rabbit TB model, it is thus the gradual accumulation of nonmetabolized SQ109 in tissues to therapeutic levels that leads to good efficacy. Our results also provide new insights into how SQ109 binds to its target MmpL3, based on our mass spectroscopy results which indicate that the charge in SQ109 is primarily localized on the geranyl nitrogen, explaining the very short distance to a key Asp found in the X-ray structure of SQ109 bound to MmpL3.


Assuntos
Mycobacterium tuberculosis , Preparações Farmacêuticas , Tuberculose , Animais , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Escherichia coli , Coelhos , Tuberculose/tratamento farmacológico
10.
J Enzyme Inhib Med Chem ; 36(1): 1751-1759, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34325595

RESUMO

Molecular hybridisation of four bioactive fragments piperazine, substituted-benzofuran, amino acids, and 2,4-dinitrobenzenesulfonamide as single molecular architecture was designed. A series of new hybrids were synthesised and subjected to evaluation for their inhibitory activity against Mycobacterium tuberculosis (Mtb) H37Rv. 4d-f and 4o found to exhibit MIC as 1.56 µg/mL, equally active as ethambutol whereas 4a, 4c, 4j displayed MIC 0.78 µg/mL were superior to ethambutol. Tested compounds demonstrated an excellent safety profile with very low toxicity, good selectivity index, and antioxidant properties. All the newly synthesised compounds were thoroughly characterised by analytical methods. The result was further supported by molecular modelling studies on the crystal structure of Mycobacterium tuberculosis enoyl reductase.


Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Benzenossulfonatos/química , Benzofuranos/química , Desenho de Fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Piperazina/química , Amidas/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Análise Espectral/métodos
11.
J Enzyme Inhib Med Chem ; 36(1): 1472-1487, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34210233

RESUMO

A series of 1,2,3-trisubstituted indolizines (2a-2f, 3a-3d, and 4a-4c) were screened for in vitro whole-cell anti-tubercular activity against the susceptible H37Rv and multidrug-resistant (MDR) Mycobacterium tuberculosis (MTB) strains. Compounds 2b-2d, 3a-3d, and 4a-4c were active against the H37Rv-MTB strain with minimum inhibitory concentration (MIC) ranging from 4 to 32 µg/mL, whereas the indolizines 4a-4c, with ethyl ester group at the 4-position of the benzoyl ring also exhibited anti-MDR-MTB activity (MIC = 16-64 µg/mL). In silico docking study revealed the enoyl-acyl carrier protein reductase (InhA) and anthranilate phosphoribosyltransferase as potential molecular targets for the indolizines. The X-ray diffraction analysis of the compound 4b was also carried out. Further, a safety study (in silico and in vitro) demonstrated no toxicity for these compounds. Thus, the indolizines warrant further development and may represent a novel promising class of InhA inhibitors and multi-targeting agents to combat drug-sensitive and drug-resistant MTB strains.


Assuntos
Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Indolizinas/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Oxirredutases/antagonistas & inibidores , Antituberculosos/química , Indolizinas/química , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/enzimologia
12.
Methods Mol Biol ; 2314: 323-342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235661

RESUMO

With increasing prevalence of antimicrobial resistance, a fundamental goal of antibiotic discovery is to uncover new small molecules that prevent growth of pathogenic bacteria through diverse mechanisms of action. This goal is particularly pertinent for tuberculosis, caused by Mycobacterium tuberculosis. In this chapter, we describe the application of a chemical-genetic method, PROSPECT (primary screening of strains to prioritize expanded chemistry and targets), for sensitively detecting small molecule bioactivity using a pooled panel of hypomorphs (strains depleted in a particular essential gene) of M. tuberculosis. We describe statistical and heuristic approaches to assign small molecule mechanism of action from the resulting chemical-genetic interaction profiles.


Assuntos
Antituberculosos/classificação , Antituberculosos/isolamento & purificação , Proteínas de Bactérias/metabolismo , Descoberta de Drogas , Genes Essenciais , Mycobacterium tuberculosis/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla , Humanos , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/metabolismo , Bibliotecas de Moléculas Pequenas/classificação , Bibliotecas de Moléculas Pequenas/isolamento & purificação , Especificidade por Substrato
13.
Methods Mol Biol ; 2314: 595-609, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235672

RESUMO

Antimicrobial susceptibility testing is the mainstay of tuberculosis drug development programs. In this chapter, we describe methods for determination of the minimum inhibitory concentration of compounds against Mycobacterium tuberculosis growing in liquid media as a function of carbon source, detergent, and environmental stress imposed by acidic pH as well as reactive nitrogen intermediates. Methods for determining the effect of bovine serum albumin in the growth medium on antimicrobial susceptibility are also described. Finally, we provide a method for antimicrobial susceptibility testing on agar medium.


Assuntos
Ágar/química , Antituberculosos/farmacologia , Meios de Cultura/farmacologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Soroalbumina Bovina/metabolismo , Tuberculose/tratamento farmacológico , Carbono/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Estresse Fisiológico , Tuberculose/microbiologia , Tuberculose/patologia
14.
Methods Mol Biol ; 2314: 637-648, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235674

RESUMO

The concept of antimicrobial susceptibility testing is an essential part of clinical microbiology. Antimicrobial testing has played a central role in the identification of new antibiotics and defining their clinical uses. Here we describe different approaches to determine the activity of compounds in medium or high-throughput format.


Assuntos
Trifosfato de Adenosina/metabolismo , Antituberculosos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos
15.
Methods Mol Biol ; 2314: 611-635, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235673

RESUMO

Models of nonreplication help us understand the biology of persistent Mycobacterium tuberculosis. High throughput screening (HTS) against nonreplicating M. tuberculosis may lead to identification of tool compounds that affect pathways on which bacterial survival depends in such states and to development of drugs that can overcome phenotypic resistance to conventional antimycobacterial agents, which are mostly active against replicating M. tuberculosis. We describe a multistress model of nonreplication that mimics some of the microenvironmental conditions that M. tuberculosis faces in the host as adapted for HTS. The model includes acidic pH, mild hypoxia, a flux of nitric oxide, and other reactive nitrogen intermediates arising from nitrite at low pH and low concentrations of a fatty acid (butyrate) as a carbon source.


Assuntos
Antituberculosos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Hipóxia/fisiopatologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Óxido Nítrico/metabolismo , Estresse Fisiológico , Tuberculose/tratamento farmacológico , Humanos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia , Tuberculose/patologia
16.
Methods Mol Biol ; 2314: 703-713, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235676

RESUMO

Treatment of tuberculosis necessitates combination therapy. Therefore, development of new tuberculosis therapies should consider multidrug effects because specific combinations may improve or reduce treatment efficacy through synergistic or antagonistic drug interactions, respectively. The standard assay of drug interactions is a checkerboard assay, wherein the drug-dose combinations are well-sampled across broad dose ranges. However, measuring three or more drugs in combination with a checkerboard assay is impractical due to the high number of measurements. We describe a protocol for efficient and quantitative measurement of drug interactions called diagonal measurement of n-way drug interactions (DiaMOND). DiaMOND is a geometric optimization of the checkerboard assay, using only the diagonal and axes of the checkerboard. This protocol describes how to perform DiaMOND experiments and analysis for Mycobacterium tuberculosis growth inhibition in standard growth conditions. As a guide on how to customize the DiaMOND assay, this protocol includes notes to modify the procedures for other growth conditions and outcome measures.


Assuntos
Antituberculosos/farmacologia , Interações Medicamentosas , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Tuberculose/tratamento farmacológico , Combinação de Medicamentos , Humanos , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia
17.
Methods Mol Biol ; 2314: 715-731, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235677

RESUMO

Hollow fiber systems (HFSs) have been widely applied to study pharmacokinetic-pharmacodynamic (PK-PD) relationships in antibiotic research and development. The system comprises a bundle of high-density hollow capillary fibers that conduct a flow of medium with or without drug and an extra-capillary space (ECS) inoculated with the pathogen of interest. The semipermeable membrane of the hollow fibers allows for rapid exchange of small molecule drugs and solutes, while the pathogen is restricted to the ECS. The unique properties of the HFS are (1) the ability to simulate any PK profile within the fibers and ECS, including plasma or site-of-disease PK profiles, (2) the ability to simultaneously input several drugs with different half-lives, (3) the ability to manipulate growth conditions such as medium composition, carbon source, and pH, and (4) the ability to sample in both compartments in order to monitor drug concentrations and bacterial growth kinetics over time. The system is particularly suited for Mycobacterium tuberculosis research in a biosafety level 3 (BSL3) environment since pathogenic bacteria are sequestered in an isolated compartment. The HFS was qualified by the European Medicines Agency for antituberculosis drug development in 2015. Here, we describe the standard procedures used to study the growth kinetics of M. tuberculosis in the HFS and the killing effect of first-line antituberculous drugs applied under simulated human PK conditions. This animal-sparing and economical tool can be applied to optimize dosing schedules that minimize emergence of resistance and to prioritize drug regimens that accelerate sterilization.


Assuntos
Antituberculosos/farmacologia , Reatores Biológicos , Descoberta de Drogas/métodos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Preparações Farmacêuticas/administração & dosagem , Tuberculose/tratamento farmacológico , Animais , Testes Diagnósticos de Rotina , Tolerância a Medicamentos , Humanos , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia
18.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208536

RESUMO

A ChCl: Gly (DESs) promoted environmentally benign method was developed for the first time using the reaction of aryl aldehydes and dimedone to give excellent yields of xanthene analogues. The major application of this present protocol is the use of green solvent, a wide range of substrate, short reaction times, ease of recovery, the recyclability of the catalyst, high reaction yield, and ChCl: Gly as an alternative catalyst and solvent. In addition to this, all the synthesized compounds were evaluated for their in vitro antimycobacterial activity against M. tuberculosis H37Ra (MTB) and M. bovis BCG strains. The compounds 3d, 3e, 3f, and 3j showed significant antitubercular activity against MTB and M. bovis strains with minimum inhibitory concentration (MIC) values of 2.5-15.10 µg/mL and 0.26-14.92 µg/mL, respectively. The compounds 3e, 3f, and 3j were found to be nontoxic against MCF-7, A549, HCT 116, and THP-1 cell lines. All the prepared compounds were confirmed by 1H NMR and 13C NMR analysis.


Assuntos
Cicloexanonas/química , Solventes/química , Xantenos/síntese química , Aldeídos/química , Antituberculosos/farmacologia , Linhagem Celular Tumoral , Glicerol/química , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Relação Estrutura-Atividade , Xantenos/química , Xantenos/isolamento & purificação
19.
BMC Infect Dis ; 21(1): 605, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34171989

RESUMO

BACKGROUND: Detection of pyrazinamide (PZA) resistance in Mycobacterium tuberculosis (TB) patients is critical, especially in dealing with multidrug-resistant Mycobacterium tuberculosis (MDR-TB) case. Up to date, PZA drug susceptibility testing (DST) has not been regularly performed in China. The prevalence and molecular characteristics of PZA resistance in M.tuberculosis isolates, especially MDR-TB have not been studied in Ningbo, China. This study aimed to analyze the phenotypic and molecular characterization of PZA resistance among MDR-TB isolates in Ningbo. METHODS: A total of 110 MDR-TB isolates were collected from the TB patients who were recorded at local TB dispensaries in Ningbo. All clinical isolates were examined by drug susceptibility testing and genotyping. DNA sequencing was used to detect mutations in the pncA gene associated with PZA resistance. RESULTS: The prevalence of PZA resistance among MDR-TB strains in Ningbo was 59.1%. With regard to the history and the outcome of treatments among MDR-TB cases, the percentages of re-treated MDR-TB patients in the PZA-resistant group and of successful patients in PZA-susceptible group were significantly higher than the ones in the PZA-susceptible group and in the PZA-resistant group, respectively (P = 0.027, P = 0.020). The results showed that the resistance of streptomycin (67.7% vs 46.7%, P = 0.027), ethambutol (56.9% vs 33.3%, P = 0.015), ofloxacin (43.1% vs 11.1%, P = 0.000), levofloxacin (43.1% vs 11.1%, P = 0.000), pre-XDR (pre-Xtensively Drug Resistance) (38.5% vs 15.6%, P = 0.009), were more frequently adverted among PZA-resistant isolates compared with PZA-susceptible isolates. In addition, 110 MDR-TB was composed of 87 (PZA resistant, 78.5%) Beijing strains and 23 (PZA resistant, 21.5%) non-Beijing strains. Fifty-four out of 65 (83.1%) PZA-resistant MDR strains harbored a mutation located in the pncA gene and the majority (90.7%) were point mutations. Compared with the phenotypic characterization, DNA sequencing of pncA has sensitivity and specificity of 83.1 and 95.6%. CONCLUSION: The mutations within pncA gene was the primary mechanism of PZA resistance among MDR-TB and DNA sequencing of pncA gene could provide a rapid detection evidence in PZA drug resistance of MDR-TB in Ningbo.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazinamida/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidoidrolases/genética , Pequim , China , DNA Bacteriano , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Mycobacterium tuberculosis/isolamento & purificação , Fenótipo , Análise de Sequência de DNA , Adulto Jovem
20.
Antimicrob Agents Chemother ; 65(8): e0028221, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34097493

RESUMO

Anti-infective drug discovery is greatly facilitated by the availability of in vitro assays that are more proficient at predicting the preclinical success of screening hits. Tuberculosis (TB) drug discovery is hindered by the relatively slow growth rate of Mycobacterium tuberculosis and the use of whole-cell-based in vitro assays that are inherently time-consuming, and for these reasons, rapid, noninvasive bioluminescence-based assays have been widely used in anti-TB drug discovery and development. In this study, in vitro assays that employ autoluminescent M. tuberculosis were optimized to determine MIC, minimum bactericidal concentration (MBC), time-kill curves, activity against macrophage internalized M. tuberculosis (90% effective concentration [EC90]), and postantibiotic effect (PAE) to provide rapid and dynamic biological information. Standardization of the luminescence-based MIC, MBC, time-kill, EC90, and PAE assays was accomplished by comparing results of established TB drugs and two ClpC1-targeting TB leads, ecumicin and rufomycin, to those obtained from conventional assays and/or to previous studies. Cumulatively, the use of the various streamlined luminescence-based in vitro assays has reduced the time for comprehensive in vitro profiling (MIC, MBC, time-kill, EC90, and PAE) by 2 months. The luminescence-based in vitro MBC and EC90 assays yield time and concentration-dependent kill information that can be used for pharmacokinetic-pharmacodynamic (PK-PD) modeling. The MBC and EC90 time-kill graphs revealed a significantly more rapid bactericidal activity for ecumicin than rufomycin. The PAEs of both ecumicin and rufomycin were comparable to that of the first-line TB drug rifampin. The optimization of several nondestructive, luminescence-based TB assays facilitates the in vitro profiling of TB drug leads in an efficient manner.


Assuntos
Anti-Infecciosos , Mycobacterium tuberculosis , Tuberculose , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Tuberculose/tratamento farmacológico
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