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1.
BMC Infect Dis ; 22(1): 705, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002805

RESUMO

BACKGROUND: Tuberculosis (TB) is a communicable, preventable and curable disease caused by the bacterium Mycobacterium tuberculosis (MTB). Peru is amongst the 30 countries with the highest burden of multidrug-resistant tuberculosis (MDR-TB) worldwide. In the fight against drug-resistant tuberculosis, the UKMYC6 microdilution plate was developed and validated by the CRyPTIC project. The objective of the study was to evaluate the use of the broth microdilution (BMD) plate methodology for susceptibility testing of drug-resistant MTB strains in Peru. METHODS: MTB strains isolated between 2015 and 2018 in Peru were used. 496 nationally-representative strains determined as drug-resistant by the routine 7H10 Agar Proportion Method (APM) were included in the present study. The Minimum Inhibitory Concentration (MIC) of 13 antituberculosis drugs were determined for each strain using the UKMYC6 microdilution plates. Diagnostic agreement between APM and BMD plate methodology was determined for rifampicin, isoniazid, ethambutol, ethionamide, kanamycin and levofloxacin. Phenotypes were set using binary (or ternary) classification based on Epidemiological cut-off values (ECOFF/ECV) proposed by the CRyPTIC project. Whole Genome Sequencing (WGS) was performed on strains with discrepant results between both methods. RESULTS: MIC distributions were determined for 13 first- and second-line anti-TB drugs, including new (bedaquiline, delamanid) and repurposed (clofazimine, linezolid) agents. MIC results were available for 80% (397/496) of the strains at 14 days and the remainder at 21 days. The comparative analysis determined a good agreement (0.64 ≤ k ≤ 0.79) for the drugs rifampicin, ethambutol, ethionamide and kanamycin, and the best agreement (k > 0.8) for isoniazid and levofloxacin. Overall, 12% of MIC values were above the UKMYC6 plate dilution ranges, most notably for the drugs rifampicin and rifabutin. No strain presented MICs higher than the ECOFF/ECV values for the new or repurposed drugs. Discrepant analysis using genotypic susceptibility testing by WGS supported half of the results obtained by APM (52%, 93/179) and half of those obtained by BMD plate methodology (48%, 86/179). CONCLUSIONS: The BMD methodology using the UKMYC6 plate allows the complete susceptibility characterization, through the determination of MICs, of drug-resistant MTB strains in Peru. This methodology shows good diagnostic performances for rifampicin, isoniazid, ethambutol, ethionamide, kanamycin and levofloxacin. It also allows for the characterization of MICs for other drugs used in previous years against tuberculosis, as well as for new and repurposed drugs recently introduced worldwide.


Assuntos
Mycobacterium tuberculosis , Tuberculose dos Linfonodos , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Etambutol/farmacologia , Etionamida , Humanos , Isoniazida , Canamicina , Levofloxacino , Testes de Sensibilidade Microbiana , Peru , Rifampina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
2.
J Antimicrob Chemother ; 77(9): 2489-2499, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35678468

RESUMO

BACKGROUND: The WHO-endorsed shorter-course regimen for MDR-TB includes high-dose isoniazid. The pharmacokinetics of high-dose isoniazid within MDR-TB regimens has not been well described. OBJECTIVES: To characterize isoniazid pharmacokinetics at 5-15 mg/kg as monotherapy or as part of the MDR-TB treatment regimen. METHODS: We used non-linear mixed-effects modelling to evaluate the combined data from INHindsight, a 7 day early bactericidal activity study with isoniazid monotherapy, and PODRtb, an observational study of patients on MDR-TB treatment including terizidone, pyrazinamide, moxifloxacin, kanamycin, ethionamide and/or isoniazid. RESULTS: A total of 58 and 103 participants from the INHindsight and PODRtb studies, respectively, were included in the analysis. A two-compartment model with hepatic elimination best described the data. N-acetyltransferase 2 (NAT2) genotype caused multi-modal clearance, and saturable first-pass was observed beyond 10 mg/kg dosing. Saturable isoniazid kinetics predicted an increased exposure of approximately 50% beyond linearity at 20 mg/kg dosing. Participants treated with the MDR-TB regimen had a 65.6% lower AUC compared with participants on monotherapy. Ethionamide co-administration was associated with a 29% increase in isoniazid AUC. CONCLUSIONS: Markedly lower isoniazid exposures were observed in participants on combination MDR-TB treatment compared with monotherapy. Isoniazid displays saturable kinetics at doses >10 mg/kg. The safety implications of these phenomena remain unclear.


Assuntos
Arilamina N-Acetiltransferase , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Antituberculosos/efeitos adversos , Arilamina N-Acetiltransferase/farmacologia , Etionamida/farmacologia , Etionamida/uso terapêutico , Humanos , Isoniazida/farmacocinética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico
3.
Cochrane Database Syst Rev ; 5: CD014841, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35583175

RESUMO

BACKGROUND: The World Health Organization (WHO) End TB Strategy stresses universal access to drug susceptibility testing (DST). DST determines whether Mycobacterium tuberculosis bacteria are susceptible or resistant to drugs. Xpert MTB/XDR is a rapid nucleic acid amplification test for detection of tuberculosis and drug resistance in one test suitable for use in peripheral and intermediate level laboratories. In specimens where tuberculosis is detected by Xpert MTB/XDR, Xpert MTB/XDR can also detect resistance to isoniazid, fluoroquinolones, ethionamide, and amikacin. OBJECTIVES: To assess the diagnostic accuracy of Xpert MTB/XDR for pulmonary tuberculosis in people with presumptive pulmonary tuberculosis (having signs and symptoms suggestive of tuberculosis, including cough, fever, weight loss, night sweats). To assess the diagnostic accuracy of Xpert MTB/XDR for resistance to isoniazid, fluoroquinolones, ethionamide, and amikacin in people with tuberculosis detected by Xpert MTB/XDR, irrespective of rifampicin resistance (whether or not rifampicin resistance status was known) and with known rifampicin resistance. SEARCH METHODS: We searched multiple databases to 23 September 2021. We limited searches to 2015 onwards as Xpert MTB/XDR was launched in 2020. SELECTION CRITERIA: Diagnostic accuracy studies using sputum in adults with presumptive or confirmed pulmonary tuberculosis. Reference standards were culture (pulmonary tuberculosis detection); phenotypic DST (pDST), genotypic DST (gDST),composite (pDST and gDST) (drug resistance detection). DATA COLLECTION AND ANALYSIS: Two review authors independently reviewed reports for eligibility and extracted data using a standardized form. For multicentre studies, we anticipated variability in the type and frequency of mutations associated with resistance to a given drug at the different centres and considered each centre as an independent study cohort for quality assessment and analysis. We assessed methodological quality with QUADAS-2, judging risk of bias separately for each target condition and reference standard. For pulmonary tuberculosis detection, owing to heterogeneity in participant characteristics and observed specificity estimates, we reported a range of sensitivity and specificity estimates and did not perform a meta-analysis. For drug resistance detection, we performed meta-analyses by reference standard using bivariate random-effects models. Using GRADE, we assessed certainty of evidence of Xpert MTB/XDR accuracy for detection of resistance to isoniazid and fluoroquinolones in people irrespective of rifampicin resistance and to ethionamide and amikacin in people with known rifampicin resistance, reflecting real-world situations. We used pDST, except for ethionamide resistance where we considered gDST a better reference standard. MAIN RESULTS: We included two multicentre studies from high multidrug-resistant/rifampicin-resistant tuberculosis burden countries, reporting on six independent study cohorts, involving 1228 participants for pulmonary tuberculosis detection and 1141 participants for drug resistance detection. The proportion of participants with rifampicin resistance in the two studies was 47.9% and 80.9%. For tuberculosis detection, we judged high risk of bias for patient selection owing to selective recruitment. For ethionamide resistance detection, we judged high risk of bias for the reference standard, both pDST and gDST, though we considered gDST a better reference standard. Pulmonary tuberculosis detection - Xpert MTB/XDR sensitivity range, 98.3% (96.1 to 99.5) to 98.9% (96.2 to 99.9) and specificity range, 22.5% (14.3 to 32.6) to 100.0% (86.3 to 100.0); median prevalence of pulmonary tuberculosis 91.3%, (interquartile range, 89.3% to 91.8%), (2 studies; 1 study reported on 2 cohorts, 1228 participants; very low-certainty evidence, sensitivity and specificity). Drug resistance detection People irrespective of rifampicin resistance - Isoniazid resistance: Xpert MTB/XDR summary sensitivity and specificity (95% confidence interval (CI)) were 94.2% (87.5 to 97.4) and 98.5% (92.6 to 99.7) against pDST, (6 cohorts, 1083 participants, moderate-certainty evidence, sensitivity and specificity). - Fluoroquinolone resistance: Xpert MTB/XDR summary sensitivity and specificity were 93.2% (88.1 to 96.2) and 98.0% (90.8 to 99.6) against pDST, (6 cohorts, 1021 participants; high-certainty evidence, sensitivity; moderate-certainty evidence, specificity). People with known rifampicin resistance - Ethionamide resistance: Xpert MTB/XDR summary sensitivity and specificity were 98.0% (74.2 to 99.9) and 99.7% (83.5 to 100.0) against gDST, (4 cohorts, 434 participants; very low-certainty evidence, sensitivity and specificity). - Amikacin resistance: Xpert MTB/XDR summary sensitivity and specificity were 86.1% (75.0 to 92.7) and 98.9% (93.0 to 99.8) against pDST, (4 cohorts, 490 participants; low-certainty evidence, sensitivity; high-certainty evidence, specificity). Of 1000 people with pulmonary tuberculosis, detected as tuberculosis by Xpert MTB/XDR: - where 50 have isoniazid resistance, 61 would have an Xpert MTB/XDR result indicating isoniazid resistance: of these, 14/61 (23%) would not have isoniazid resistance (FP); 939 (of 1000 people) would have a result indicating the absence of isoniazid resistance: of these, 3/939 (0%) would have isoniazid resistance (FN). - where 50 have fluoroquinolone resistance, 66 would have an Xpert MTB/XDR result indicating fluoroquinolone resistance: of these, 19/66 (29%) would not have fluoroquinolone resistance (FP); 934 would have a result indicating the absence of fluoroquinolone resistance: of these, 3/934 (0%) would have fluoroquinolone resistance (FN). - where 300 have ethionamide resistance, 296 would have an Xpert MTB/XDR result indicating ethionamide resistance: of these, 2/296 (1%) would not have ethionamide resistance (FP); 704 would have a result indicating the absence of ethionamide resistance: of these, 6/704 (1%) would have ethionamide resistance (FN). - where 135 have amikacin resistance, 126 would have an Xpert MTB/XDR result indicating amikacin resistance: of these, 10/126 (8%) would not have amikacin resistance (FP); 874 would have a result indicating the absence of amikacin resistance: of these, 19/874 (2%) would have amikacin resistance (FN). AUTHORS' CONCLUSIONS: Review findings suggest that, in people determined by Xpert MTB/XDR to be tuberculosis-positive, Xpert MTB/XDR provides accurate results for detection of isoniazid and fluoroquinolone resistance and can assist with selection of an optimised treatment regimen. Given that Xpert MTB/XDR targets a limited number of resistance variants in specific genes, the test may perform differently in different settings. Findings in this review should be interpreted with caution. Sensitivity for detection of ethionamide resistance was based only on Xpert MTB/XDR detection of mutations in the inhA promoter region, a known limitation. High risk of bias limits our confidence in Xpert MTB/XDR accuracy for pulmonary tuberculosis. Xpert MTB/XDR's impact will depend on its ability to detect tuberculosis (required for DST), prevalence of resistance to a given drug, health care infrastructure, and access to other tests.


Assuntos
Antibióticos Antituberculose , Mycobacterium tuberculosis , Tuberculose dos Linfonodos , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Adulto , Amicacina/farmacologia , Amicacina/uso terapêutico , Antibióticos Antituberculose/farmacologia , Antibióticos Antituberculose/uso terapêutico , Farmacorresistência Bacteriana/genética , Etionamida/farmacologia , Etionamida/uso terapêutico , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Rifampina/farmacologia , Rifampina/uso terapêutico , Sensibilidade e Especificidade , Tuberculose dos Linfonodos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico
4.
Sci Transl Med ; 14(643): eaaz6280, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35507672

RESUMO

The sensitivity of Mycobacterium tuberculosis, the pathogen that causes tuberculosis (TB), to antibiotic prodrugs is dependent on the efficacy of the activation process that transforms the prodrugs into their active antibacterial moieties. Various oxidases of M. tuberculosis have the potential to activate the prodrug ethionamide. Here, we used medicinal chemistry coupled with a phenotypic assay to select the N-acylated 4-phenylpiperidine compound series. The lead compound, SMARt751, interacted with the transcriptional regulator VirS of M. tuberculosis, which regulates the mymA operon encoding a monooxygenase that activates ethionamide. SMARt751 boosted the efficacy of ethionamide in vitro and in mouse models of acute and chronic TB. SMARt751 also restored full efficacy of ethionamide in mice infected with M. tuberculosis strains carrying mutations in the ethA gene, which cause ethionamide resistance in the clinic. SMARt751 was shown to be safe in tests conducted in vitro and in vivo. A model extrapolating animal pharmacokinetic and pharmacodynamic parameters to humans predicted that as little as 25 mg of SMARt751 daily would allow a fourfold reduction in the dose of ethionamide administered while retaining the same efficacy and reducing side effects.


Assuntos
Mycobacterium tuberculosis , Pró-Fármacos , Tuberculose , Animais , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Etionamida/química , Etionamida/farmacologia , Etionamida/uso terapêutico , Camundongos , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Tuberculose/tratamento farmacológico
5.
Comput Biol Chem ; 98: 107677, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35397466

RESUMO

EthA is an NADPH-specific flavin adenine dinucleotide (FAD) containing monooxygenase that activates the -second-line drug ethionamide (ETH). ETH gets converted to an active form after interaction with the EthA (monooxygenase) protein. Upon activation, ETH interacts with NAD+ to form an ETH-NAD adduct, which hampers the activity of InhA (Enoyl-[(acyl-carrier-protein) reductase (NADH)]. This, in turn, inhibits the cell wall synthesis, thus killing the Mycobacterium tuberculosis (Mtb). Mutations in the EthA gene can modulate ETH activation. The mutation at 202 position (Val202-Leu) of EthA protein has been reported frequently in ETH resistance. In this study, the effect of this mutation on the function of the EthA protein was examined through structural and functional analysis. Molecular docking of wild type and mutated EthA protein with ETH were compared to inspect the effect of mutation on molecular mechanism of drug resistant. Docking results corroborated that the lower docking score of the mutant protein, larger binding cavity, and lower affinity towards ETH resulted in a less compact and energetically less stable structure than the wild type protein. The computational outcome was authenticated by in-vitro experiments. The wild type and mutated genes were cloned and expressed in M. smegmatis, a surrogate host. Antibiotic susceptibility testing demonstrated that the mutant showed high growth and survival in the presence of the ETH drug. Overall, the results indicated that a mutation in the intergenic region of EthA protein could result in the altered conversion of ETH to the active form, resulting in differential ETH sensitivity for M. smegmatis carrying the wild type and mutant gene.


Assuntos
Etionamida , Mycobacterium tuberculosis , Antituberculosos/metabolismo , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Tolerância a Medicamentos , Etionamida/metabolismo , Etionamida/farmacologia , Oxigenases de Função Mista/genética , Simulação de Acoplamento Molecular , Mutação , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/metabolismo
7.
J Appl Toxicol ; 42(9): 1533-1547, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35315511

RESUMO

Ethionamide (ETH), a second-line drug for multidrug-resistant tuberculosis, is known to cause hepatic steatosis in rats and humans. To investigate predictive biomarkers for ETH-induced steatosis, we performed lipidomics analysis using plasma and liver samples collected from rats treated orally with ETH at 30 and 100 mg/kg for 14 days. The ETH-treated rats developed hepatic steatosis with Oil Red O staining-positive vacuolation in the centrilobular hepatocytes accompanied by increased hepatic contents of triglycerides (TG) and decreased plasma TG and total cholesterol levels. A multivariate analysis for lipid profiles revealed differences in each of the 35 lipid species in the plasma and liver between the control and the ETH-treated rats. Of those lipids, phosphatidylcholine (PC) (18:0/20:4) decreased dose-dependently in both the plasma and liver. Moreover, serum TG-rich very low-density lipoprotein (VLDL) levels, especially the large particle fraction of VLDL composed of PC containing arachidonic acid (20:4) involved in hepatic secretion of TG, were decreased dose-dependently. In conclusion, the decreased PC (18:0/20:4) in the liver, possibly leading to suppression of hepatic TG secretion, was considered to be involved in the pathogenesis of the ETH-induced hepatic steatosis. Therefore, plasma PC (18:0/20:4) levels are proposed as mechanism-related biomarkers for ETH-induced hepatic steatosis.


Assuntos
Etionamida , Fígado Gorduroso , Animais , Biomarcadores , Etionamida/uso terapêutico , Etionamida/toxicidade , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/tratamento farmacológico , Humanos , Fígado/patologia , Fosfatidilcolinas , Ratos , Triglicerídeos/toxicidade
8.
Microbiol Spectr ; 10(2): e0251621, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35311541

RESUMO

Our objective was to evaluate the performance of whole-genome sequencing (WGS) from early positive liquid cultures for predicting Mycobacterium tuberculosis complex (MTBC) drug resistance. Clinical isolates were obtained from tuberculosis patients at Shanghai Pulmonary Hospital (SPH). Antimicrobial susceptibility testing (AST) was performed, and WGS from early Bactec mycobacterial growth indicator tube (MGIT) 960-positive liquid cultures was performed to predict the drug resistance using the TB-Profiler informatics platform. A total of 182 clinical isolates were enrolled in this study. Using phenotypic AST as the gold standard, the overall sensitivity and specificity for WGS were, respectively, 97.1% (89.8 to 99.6%) and 90.4% (83.4 to 95.1%) for rifampin, 91.0% (82.4 to 96.3%) and 95.2% (89.1 to 98.4%) for isoniazid, 100.0% (89.4 to 100.0%) and 87.3% (80.8 to 92.1%) for ethambutol, 96.6% (88.3 to 99.6%) and 61.8% (52.6 to 70.4%) for streptomycin, 86.8% (71.9 to 95.6%) and 95.8% (91.2 to 98.5%) for moxifloxacin, 86.5% (71.2 to 91.5%) and 95.2% (90.3 to 98.0%) for ofloxacin, 100.0% (54.1 to 100.0%) and 67.6% (60.2 to 74.5%) for amikacin, 100.0% (63.1 to 100.0%) and 67.2% (59.7 to 74.2%) for kanamycin, 62.5% (24.5 to 91.5%) and 88.5% (82.8 to 92.8%) for ethionamide, 33.3% (4.3 to 77.7%) and 98.3% (95.1 to 99.7%) for para-aminosalicylic acid, and 0.0% (0.0 to 12.3%) and 100.0% (97.6 to 100.0%) for cycloserine. The concordances of WGS-based AST and phenotypic AST were as follows: rifampin (92.9%), isoniazid (93.4%), ethambutol (89.6%), streptomycin (73.1%), moxifloxacin (94.0%), ofloxacin (93.4%), amikacin (68.7%), kanamycin (68.7%), ethionamide (87.4%), para-aminosalicylic acid (96.2%) and cycloserine (84.6%). We conclude that WGS could be a promising approach to predict MTBC resistance from early positive liquid cultures. IMPORTANCE In this study, we used whole-genome sequencing (WGS) from early positive liquid (MGIT) cultures instead of solid cultures to predict drug resistance of 182 Mycobacterium tuberculosis complex (MTBC) clinical isolates to predict drug resistance using the TB-Profiler informatics platform. Our study indicates that WGS may be a promising method for predicting MTBC resistance using early positive liquid cultures.


Assuntos
Ácido Aminossalicílico , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Amicacina , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , China , Ciclosserina , Resistência a Medicamentos , Etambutol , Etionamida , Humanos , Isoniazida , Canamicina , Testes de Sensibilidade Microbiana , Moxifloxacina , Ofloxacino , Rifampina , Estreptomicina , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
9.
Bioorg Med Chem Lett ; 60: 128604, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35123004

RESUMO

To explore effective antituberculosis agents, a new class of imidazoles and benzimidazoles linked ethionamide analogs were designed and synthesized. The elemental analysis, 1H NMR, 13C NMR and mass spectral data were used to characterize all of the novel analogs. In vitro activity against Mycobacterium tuberculosis (Mtb) H37Rv was assessed for all of the target compounds. The hydroxy and nitrile moieties on the imidazole ring, as well as the hydroxy and methoxy groups on the benzimidazole ring connected to the ethionamide side chain, were shown to be advantageous. In our cell viability experiment against the Vero cell line, all of the compounds were non-cytotoxic even at 100 µM. To confirm the powerful analogs target identification, we investigated their in vitro inhibitory action on an M. tuberculosis InhA over-expressing (Mtb InhA-OE) strain, which yielded MICs nearly twice those of the Mtb H37Rv strain. Furthermore, the results of molecular docking confirmed the experimental findings. Additionally, the molecules were evaluated in silico for ADMET and drug similarity features. The experimental observation enables the newly generated ethionamide derivatives to be attractive candidates for the creation of newer and better anti-TB agents.


Assuntos
Antituberculosos/farmacologia , Benzimidazóis/farmacologia , Etionamida/farmacologia , Imidazóis/farmacologia , Inibinas/antagonistas & inibidores , Mycobacterium tuberculosis/efeitos dos fármacos , Antituberculosos/síntese química , Antituberculosos/química , Benzimidazóis/síntese química , Benzimidazóis/química , Relação Dose-Resposta a Droga , Desenho de Fármacos , Etionamida/síntese química , Etionamida/química , Humanos , Imidazóis/síntese química , Imidazóis/química , Inibinas/metabolismo , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
10.
Proteins ; 90(5): 1142-1151, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34981576

RESUMO

Tuberculosis is an ancient disease of mankind, and its causative bacterium is Mycobacterium tuberculosis. Isoniazid is one of the most effective first-line antituberculosis drugs. As prodrugs, it and its derivative ethionamide act on enoyl-acyl carrier protein reductase (InhA) after being oxidized in bacteria, and kill the bacteria by inhibiting the formation of M. tuberculosis cell walls. However, the S94A mutation of InhA causes M. tuberculosis to develop cross-resistance to isoniazid and ethionamide. This work is dedicated to studying the cross-resistance mechanism of isoniazid and ethionamide through theoretical calculations. First, thermodynamic integral simulations are used to accurately calculate the relative binding energy of two drugs in the mutant and wild-type system. Furthermore, through classic molecular dynamic simulations and molecular mechanics generalized-Born surface area calculation, some key residues are identified and the binding affinity of isoniazid and ethionamide reduced by 9-13 kcal/mol due to S94A mutation. The hydrogen bond between Ala94 and isoniazid (ethionamide) disappeared and the energy contribution of Ala94 decreased after the mutation. In addition, the dynamic network analysis indicated that the mutation of Ser94 also indirectly affected the conformation of key residues such as Met147, Thr196, and Leu97, resulting in a reduction in the energy contribution of these residues. Finally, the binding conformation of isoniazid and ethionamide has also undergone major changes. The obtained results could provide valuable information for the future molecular design to overcome the drug resistance.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Proteínas de Bactérias/química , Etionamida/metabolismo , Etionamida/farmacologia , Humanos , Isoniazida/metabolismo , Isoniazida/farmacologia , Simulação de Dinâmica Molecular , Mutação , Mycobacterium tuberculosis/metabolismo , Oxirredutases/metabolismo , Termodinâmica
11.
Lancet Infect Dis ; 22(2): 242-249, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34627496

RESUMO

BACKGROUND: The WHO End TB Strategy requires drug susceptibility testing and treatment of all people with tuberculosis, but second-line diagnostic testing with line-probe assays needs to be done in experienced laboratories with advanced infrastructure. Fewer than half of people with drug-resistant tuberculosis receive appropriate treatment. We assessed the diagnostic accuracy of the rapid Xpert MTB/XDR automated molecular assay (Cepheid, Sunnyvale, CA, USA) to overcome these limitations. METHODS: We did a prospective study involving individuals presenting with pulmonary tuberculosis symptoms and at least one risk factor for drug resistance in four sites in India (New Delhi and Mumbai), Moldova, and South Africa between July 31, 2019, and March 21, 2020. The Xpert MTB/XDR assay was used as a reflex test to detect resistance to isoniazid, fluoroquinolones, ethionamide, amikacin, kanamycin, and capreomycin in adults with positive results for Mycobacterium tuberculosis complex on Xpert MTB/RIF or Ultra (Cepheid). Diagnostic performance was assessed against a composite reference standard of phenotypic drug-susceptibility testing and whole-genome sequencing. This study is registered with ClinicalTrials.gov, number NCT03728725. FINDINGS: Of 710 participants, 611 (86%) had results from both Xpert MTB/XDR and the reference standard for any drug and were included in analysis. Sensitivity for Xpert MTB/XDR detection of resistance was 94% (460 of 488, 95% CI 92-96) for isoniazid, 94% (222 of 235, 90-96%) for fluoroquinolones, 54% (178 of 328, 50-61) for ethionamide, 73% (60 of 82, 62-81) for amikacin, 86% (181 of 210, 81-91) for kanamycin, and 61% (53 of 87, 49-70) for capreomycin. Specificity was 98-100% for all drugs. Performance was equivalent to that of line-probe assays. The non-determinate rate of Xpert MTB/XDR (ie, invalid M tuberculosis complex detection) was 2·96%. INTERPRETATION: The Xpert MTB/XDR assay showed high diagnostic accuracy and met WHO's minimum target product profile criteria for a next-generation drug susceptibility test. The assay has the potential to diagnose drug-resistant tuberculosis rapidly and accurately and enable optimum treatment. FUNDING: German Federal Ministry of Education and Research through KfW, Dutch Ministry of Foreign Affairs, and Australian Department of Foreign Affairs and Trade.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Adulto , Amicacina/farmacologia , Amicacina/uso terapêutico , Austrália , Capreomicina/farmacologia , Capreomicina/uso terapêutico , Estudos Transversais , Farmacorresistência Bacteriana , Etionamida/farmacologia , Etionamida/uso terapêutico , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Humanos , Isoniazida/uso terapêutico , Canamicina/farmacologia , Canamicina/uso terapêutico , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Estudos Prospectivos , Rifampina/uso terapêutico , Sensibilidade e Especificidade , Escarro/microbiologia , Tuberculose/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
12.
Phys Chem Chem Phys ; 23(40): 23233-23241, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34623361

RESUMO

Ethionamide (ETH) is a high-profile drug for the treatment of patients with multidrug-resistant Mycobacterium tuberculosis and, in order to produce its inhibitory effects, it needs to be bioactivated by monooxygenase EthA. This process is under the control of the transcriptional repressors EthR and EthR2, so that their inhibition results in the boosting of ethionamide activation. Herein, through crystallographic data and computer simulations, we calculated the interaction binding energies of four inhibitors with improved in vitro potency, namely BDM76060 (PDB ID: 6HS1), BDM72201 (PDB ID: 6HRX), BDM76150 (PDB ID: 6HS2) and BDM72719 (PDB ID: 6HRY), in complexes with the transcriptional repressor EthR2, using density functional theory (DFT) within the molecular fractionation with conjugated caps (MFCC) approach. It was observed that these ligands share the same binding site within a 10.0 Å radius of the EthR2 protein; however, their structural particularities have a significant impact on the global energies of systems. The BDM72201 and BDM72719 components are weakly attached to the binding site, while BDM76060 and BDM76150 components produce stronger bonds, corroborating with experimental studies demonstrating that BDM76060 and BDM76150 are more successful in producing inhibitory effects. BDM76060 and BDM76150 have many functional groups that increase the contact surface with the protein and attract a more significant number of amino acid residues, being able to produce polarities that generate stronger interactions. In the current scenario of a growing number of cases of bacterial resistance, the obtained data can be used to guide clinical trials of these inhibitors and other inhibitors that act on the alternative EthR2 pathway, focusing on improving the activity of ethionamide, its effectiveness, a reduction in the treatment time and exposure to cytotoxic effects.


Assuntos
Antituberculosos/química , Etionamida/química , Proteínas Repressoras/química , Antituberculosos/metabolismo , Antituberculosos/uso terapêutico , Sítios de Ligação , Teoria da Densidade Funcional , Etionamida/metabolismo , Etionamida/uso terapêutico , Humanos , Ligantes , Simulação de Dinâmica Molecular , Mycobacterium tuberculosis/metabolismo , Proteínas Repressoras/metabolismo , Tuberculose/tratamento farmacológico
13.
Microbiol Spectr ; 9(1): e0001921, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34287057

RESUMO

Antibiotic resistance is a global challenge for tuberculosis control, and accelerating its diagnosis is critical for therapy decisions and controlling transmission. Genotype-based molecular diagnostics now play an increasing role in accelerating the detection of such antibiotic resistance, but their accuracy depends on the instructed detection of genetic variations. Genetic mobile elements such as IS6110 are established sources of genetic variation in Mycobacterium tuberculosis, but their implication in clinical antibiotic resistance has thus far been unclear. Here, we describe the discovery of an intragenic IS6110 insertion into Rv0678 that caused antibiotic resistance in an in vitro-selected M. tuberculosis isolate. The subsequent development of bioinformatics scripts allowed genome-wide analysis of intragenic IS6110 insertions causing gene disruptions in 6,426 clinical M. tuberculosis strains. This analysis identified 10,070 intragenic IS6110 insertions distributed among 333 different genes. Focusing on genes whose disruption leads to antibiotic resistance, 12 clinical isolates were identified with high confidence to be resistant to bedaquiline, clofazimine, pyrazinamide, ethionamide, and para-aminosalicylic acid because of an IS6110-mediated gene disruption event. A number of these IS6110-mediated resistant strains had identical genomic distributions of IS6110 elements and likely represent transmission events of a single resistant isolate. These data provide strong evidence that IS6110-mediated gene disruption is a clinically relevant mechanism of antibiotic resistance in M. tuberculosis that should be considered for molecular diagnostics. Concomitantly, this analysis provides a list of 333 IS6110-disrupted genes in clinical tuberculosis isolates that can be deemed nonessential for human infection. IMPORTANCE To help control the spread of drug-resistant tuberculosis and to guide treatment choices, it is important that rapid and accurate molecular diagnostic tools are used. Current molecular diagnostic tools detect the most common antibiotic-resistance-conferring mutations in the form of single nucleotide changes, small deletions, or insertions. Mobile genetic elements, named IS6110, are also known to move within the M. tuberculosis genome and cause significant genetic variations, although the role of this variation in clinical drug resistance remains unclear. In this work, we show that both in vitro and in data analyzed from 6,426 clinical M. tuberculosis strains, IS6110 elements are found that disrupt specific genes essential for the function of a number of pivotal antituberculosis drugs. By providing ample evidence of clinically relevant IS6110-mediated drug resistance, we believe that this shows that this form of genetic variation must not be overlooked in molecular diagnostics of drug resistance.


Assuntos
Antituberculosos/farmacologia , Elementos de DNA Transponíveis , Farmacorresistência Bacteriana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose/microbiologia , Clofazimina/farmacologia , Biologia Computacional , Etionamida/farmacologia , Humanos , Mutação , Mycobacterium tuberculosis/isolamento & purificação
14.
Antimicrob Agents Chemother ; 65(10): e0027821, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34310215

RESUMO

Ethionamide is recommended as part of regimens to treat multidrug-resistant and rifampicin-resistant tuberculosis. This study was conducted to (i) describe the distribution of ethionamide MICs, (ii) describe the pharmacokinetics of ethionamide, and (iii) determine the probability of attaining target area under the concentration-time curve from 0 to 24 h (AUC0-24)/MIC values associated with suppression of resistant subpopulation and microbial kill. Participants received 15 to 20 mg of drug/kg of body weight of ethionamide daily (in 500- or 750-mg doses) as part of a multidrug regimen. Pretreatment MICs of ethionamide for Mycobacterium tuberculosis sputum isolates were determined using Sensititre MYCOTB MIC plates. Plasma concentrations of ethionamide (measured predose and at 2, 4, 6, 8, and 10 h postdose) were available for 84 patients. A one-compartment disposition model, including a liver compartment capturing hepatic extraction, best described ethionamide pharmacokinetics. Clearance and volume were allometrically scaled using fat-free mass. Isoniazid coadministration reduced ethionamide clearance by 31%, resulting in a 44% increase in AUC0-24. The median (range) MIC (n = 111) was 2.5 mg/liter (<0.3 to >40 mg/liter). Simulations showed increased daily doses of ethionamide (1,250 mg, 1,500 mg, and 1,750 mg for patients weighing ≤45 kg, 46 to 70 kg, and >70 kg, respectively) resulted in the probability of attaining an area under the concentration-time curve from 0 to 24 h for the free, unbound fraction of a drug (fAUC0-24)/MIC ratio of ≥42 in more than 90% of patients only at the lowest MIC of 0.3 mg/liter. The WHO-recommended doses of ethionamide do not achieve target concentrations even for the lowest MIC measured in the cohort.


Assuntos
Etionamida , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Humanos , Isoniazida , Testes de Sensibilidade Microbiana , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
15.
Chem Res Toxicol ; 34(8): 1879-1889, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34319702

RESUMO

A chemical activation study of the thiocarbonyl-type antitubercular prodrugs, ethionamide (ETH), thioacetazone (TAZ), and isoxyl (ISO), was performed. Biomimetic oxidation of ethionamide using H2O2 (1 equiv) led to ETH-SO as the only stable S-oxide compound, which was found to occur in solution in the preferential form of a sulfine (ETH═S═O vs the sulfenic acid tautomer ETH-S-OH), as previously observed in the crystal state. It was also demonstrated that ETH-SO is capable of reacting with amines, as the putative sulfinic derivative (ETH-SO2H) was supposed to do. Unlike ETH, oxidation of TAZ did not allow observation of the mono-oxygenated species (TAZ-SO), leading directly to the more stable sulfinic acid derivative (TAZ-SO2H), which can then lose a SOxH group after further oxidation or when placed in a basic medium. It was also noticed that the unstable TAZ-SO intermediate can lead to the carbodiimide derivative as another electrophilic species. It is suggested that TAZ-SOH, TAZ-SO2H, and the carbodiimide compound can also react with NH2-containing nucleophilic species, and therefore be involved in toxic effects. Finally, ISO showed a very complex reactivity, here assigned to the coexistence of two mono-oxygenated structures, the sulfine and sulfenic acid tautomers. The mono- and dioxygenated derivatives of ISO are also highly unstable, leading to a panel of multiple metabolites, which are still reactive and likely contribute to the toxicity of this prodrug.


Assuntos
Antituberculosos/metabolismo , Etionamida/metabolismo , Feniltioureia/análogos & derivados , Pró-Fármacos/metabolismo , Tioacetazona/metabolismo , Antituberculosos/química , Etionamida/química , Peróxido de Hidrogênio/metabolismo , Modelos Moleculares , Oxirredução , Feniltioureia/química , Feniltioureia/metabolismo , Pró-Fármacos/química , Tioacetazona/química
16.
Am J Trop Med Hyg ; 104(5): 1784-1791, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33724924

RESUMO

In Pakistan, the treatment of multidrug-resistant tuberculosis (MDR-TB) with a shorter treatment regimen (STR), that is, 4-6 months of amikacin, moxifloxacin (Mfx), ethionamide, clofazimine (Cfz), pyrazinamide (Z), ethambutol (E), and high-dose isoniazid, followed by 5 months of Mfx, Cfz, Z, and E, was initiated in 2018. However, there is a lack of information about its effectiveness in Pakistani healthcare settings. Therefore, this retrospective record review of MDR-TB patients treated with STR at eight treatment sites in Pakistan aimed to fill this gap. Data were analyzed using SPSS 23. Multivariate binary logistic regression (MVBLR) analysis was conducted to find factors associated with death and treatment failure, and lost to follow-up (LTFU). A P-value < 0.05 was considered statistically significant. Of 912 MDR-TB patients enrolled at the study sites, only 313 (34.3%) eligible patients were treated with STR and included in the current study. Of them, a total of 250 (79.9%) were cured, 12 (3.8%) completed treated, 31 (9.9%) died, 16 (5.1%) were LTFU, and four (1.3%) were declared as treatment failures. The overall treatment success rate was 83.7%. In MVBLR analysis, patients' age of 41-60 (odds ratio [OR] = 4.9, P-value = 0.020) and > 60 years (OR = 3.6, P-value = 0.035), being underweight (OR = 2.7, P-value = 0.042), and previous TB treatment (OR = 0.4, P-value = 0.042) had statistically significant association with death and treatment failure, whereas patients' age of > 60 years (OR = 5.4, P-value = 0.040) and previous TB treatment (OR = 0.2, P-value = 0.008) had statistically significant association with LTFU. The treatment success rate of STR was encouraging. However, to further improve the treatment outcomes, special attention should be paid to the patients with identified risk factors.


Assuntos
Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto , Amicacina/uso terapêutico , Clofazimina/uso terapêutico , Esquema de Medicação , Etambutol/uso terapêutico , Etionamida/uso terapêutico , Feminino , Humanos , Isoniazida/uso terapêutico , Perda de Seguimento , Masculino , Pessoa de Meia-Idade , Moxifloxacina/uso terapêutico , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/patogenicidade , Paquistão , Pirazinamida/uso terapêutico , Estudos Retrospectivos , Análise de Sobrevida , Falha de Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/mortalidade , Tuberculose Resistente a Múltiplos Medicamentos/patologia
17.
Br J Clin Pharmacol ; 87(10): 3863-3870, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33620754

RESUMO

INTRODUCTION: Ethionamide is part of the drug-resistant tuberculosis regimen whose pharmacokinetic (PK) and pharmacodynamic (PD) information is limited. The aim of the study was to describe the PK and simulate doses to assess PD attainment. METHODS: This was an observational population PK study of patients admitted for drug-resistant tuberculosis at a hospital in South Africa. Nonlinear mixed-effects modelling implemented in Monolix 2019R2 was used to estimate population pharmacokinetic parameters. We performed Monte Carlo simulations to assess and optimise the dose regimen. The target Cmax range was 2.5-5 µg/mL, which is within the minimum inhibitory concentration (MIC) range. The target AUC0-24h was 140.5 µg*h/mL, which corresponds to the PK/PD target ratio AUC0-24h /MIC of 56.2. RESULTS: A one-compartment pharmacokinetic model with a lag-time, first-order absorption and elimination best described the PK of ethionamide. The lag-time, absorption rate constant (ka), volume of distribution (V/F) and clearance (Cl/F) were 0.66 hours, 0.434 h-1 , 180 L and 99.5 L/h, respectively, for a typical individual weighing 52.6 kg. Between-subject variability in lag-time, ka, V/F and Cl/F were 38%, 92%, 168% and 120%, respectively. Simulation of the recommended doses of 15-20 mg/kg, 500 mg, 750 mg and 1000 mg for patients in the weight bands <33, 33-50, 51-70 and >70 kg resulted in <17% and 3% of the patients achieving the target Cmax and AUC0-24h , respectively. CONCLUSION: There is high variability in ethionamide PK and very few patients attain the desired target exposure at standard or optimised doses. We propose individualised dose regimen optimisation.


Assuntos
Etionamida , Tuberculose Resistente a Múltiplos Medicamentos , Adulto , Antibacterianos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Método de Monte Carlo , África do Sul , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
18.
Hum Exp Toxicol ; 40(7): 1064-1073, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33345607

RESUMO

Sustained release nanoformulations of second line antitubercular drugs levofloxacin and ethionamide had shown promise in pharmacokinetics and acute and sub-acute toxicity studies. The present study evaluated the clastogenicity potential of the nanoformulations of these antitubercular agents. Clastogenicity was evaluated by (a) in vitro micronucleus assay (b) in vivo micronucleus assay in Swiss albino mice and (c) sister chromatid exchange (SCE) in CHO cell lines. Ethionamide and levofloxacin loaded nanoparticles were 312 ± 64 nm and 245 ± 24 nm in size respectively and drug encapsulation was 35.2 ± 3.1% w/w and 45.6 ± 9.4% w/w, respectively. The frequency of MN-NCE/1000 NCE and MN-PCE/1000 PCE were significantly reduced in mice treated with ethionamide nanoparticle (3.5 ± 0.9, 13.8 ± 16.68) and levofloxacin nanoparticles (5.6 ± 2.7, 16.7 ± 12.7) compared to the mice treated with free ethionamide (11.5 ± 4.1, p = 0.23 and 45.19 ± 19.21, p = 0.38) and free levofloxacin (14.7 ± 1.88, p < 0.0001 and 54.6 ± 18.1, p = 0.0017), respectively. For in vitro, micronucleus assay frequencies of micronuclei per thousand bi-nucleated cells (MN-BN/1000 BN) was 188.3 ± 20.20 and 148 ± 20.42 for ethionamide and levofloxacin nanoparticles as compared to 232.6 ± 16.04 (p = 0.52) and 175 ± 5.56 (p = 0.45) for free ethionamide and levofloxacin, respectively. The average number of SCE per cell for nanoformulation of ethionamide were not different from that of free drug (4.9 ± 0.51 vs 4.1 ± 0.55, p = 0.86). The SCE per cells were not significant difference for nanoformulation of levofloxacin (2.33 ± 1.36 vs 5.46 ± 0.25, p = 0.88). In vitro and in vivo assays have shown relatively less clastogenic potential of equivalent dose of ethionamide nanoparticles as compared to the conventional formulation.


Assuntos
Antituberculosos/toxicidade , Células Cultivadas/efeitos dos fármacos , Etionamida/toxicidade , Levofloxacino/toxicidade , Mutagênese/efeitos dos fármacos , Nanopartículas/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/toxicidade , Animais , Camundongos , Testes para Micronúcleos , Modelos Animais
19.
PLoS One ; 15(12): e0244829, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382836

RESUMO

Drug resistance (DR) remains a major challenge for tuberculosis (TB) control. Whole-genome sequencing (WGS) provides the highest genetic resolution for genotypic drug-susceptibility tests (DST). We compared DST profiles of 60 Mycobacterium tuberculosis isolates which were drug resistant according to agar proportion tests (one poly DR-TB, 34 multidrug-resistant TB and 25 extensively drug-resistant TB). We additionally performed minimum inhibitory concentration (MIC) tests using Sensititre MYCOTBI plates (MYCOTB) and a WGS-based DST. Agreement between WGS-based DST and MYCOTB was high for all drugs except ethambutol (65%) and ethionamide (62%). Isolates harboring the -15 c/t inhA promoter mutation had a significantly lower MIC for isoniazid than did isolates with the katG Ser315Thr mutation (p < 0.001). Similar patterns were seen for ethambutol (embB Gly406Asp vs. embB Met306Ile), streptomycin (gid Gly73Ala vs. rpsL Lys43Arg), moxifloxacin (gyrA Ala90Val vs. gyrA Asp94Gly) and rifabutin (rpoB Asp435Phe/Tyr/Val vs. rpoB Ser450Leu). For genotypic heteroresistance, isolates with lower proportion of mapped read tended to has lower MIC of anti-TB drugs than those with higher proportion. These results emphasize the high applicability of WGS for determination of DR-TB and the association of particular mutations with MIC levels.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana/genética , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto , Antituberculosos/uso terapêutico , Etambutol/farmacologia , Etambutol/uso terapêutico , Etionamida/farmacologia , Etionamida/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Feminino , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Sequenciamento Completo do Genoma
20.
Int J Mol Sci ; 21(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977637

RESUMO

Mesenchymal stem cells (MSCs) are a useful source for cell-based therapy of a variety of immune-mediated diseases, including neurodegenerative disorders. However, poor migration ability and survival rate of MSCs after brain transplantation hinder the therapeutic effects in the disease microenvironment. Therefore, we attempted to use a preconditioning strategy with pharmacological agents to improve the cell proliferation and migration of MSCs. In this study, we identified ethionamide via the screening of a drug library, which enhanced the proliferation of MSCs. Preconditioning with ethionamide promoted the proliferation of Wharton's jelly-derived MSCs (WJ-MSCs) by activating phosphatidylinositol 3-kinase (PI3K)/Akt and mitogen-activated protein kinase/extracellular signal-regulated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK)1/2 signaling. Preconditioning with ethionamide also enhanced the migration ability of MSCs by upregulating expression of genes associated with migration, such as C-X-C motif chemokine receptor 4 (CXCR4) and C-X-C motif chemokine ligand 12 (CXCL12). Furthermore, preconditioning with ethionamide stimulated the secretion of paracrine factors, including neurotrophic and growth factors in MSCs. Compared to naïve MSCs, ethionamide-preconditioned MSCs (ETH-MSCs) were found to survive longer in the brain after transplantation. These results suggested that enhancing the biological process of MSCs induced by ethionamide preconditioning presents itself as a promising strategy for enhancing the effectiveness of MSCs-based therapies.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Etionamida/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Xenoenxertos , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Camundongos
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