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1.
Future Microbiol ; 18: 107-116, 2023 01.
Article in English | MEDLINE | ID: mdl-36661097

ABSTRACT

Background: There is critical need for new therapeutic options for treatment of diseases caused by mycobacteria. Materials & methods: Gallesia integrifolia essential oils (EOs) and crude extracts (CEs) were tested for their anti-Mycobacterium tuberculosis and anti-nontuberculous mycobacteria activity. Results: Minimum inhibitory concentration (MIC) of EOs ranged from 15.63 to 62.5 µg/ml against M. tuberculosis and 62.5 to >250 µg/ml against nontuberculous mycobacteria. CEs showed low activity. All EO tested demonstrated synergism with antituberculosis drugs. The cytotoxicity of EOs and CEs, in different cell lines, showed selectivity index from 2.2 to 9.8 and >0.056 to 2.0, respectively. Conclusion: G. integrifolia EOs are a candidate for the development of new therapeutic options in the treatment of tuberculosis and other mycobacterial diseases.


Subject(s)
Mycobacterium Infections , Mycobacterium tuberculosis , Oils, Volatile , Humans , Oils, Volatile/pharmacology , Antitubercular Agents/pharmacology , Nontuberculous Mycobacteria , Microbial Sensitivity Tests
2.
Future Microbiol ; 17: 267-280, 2022 03.
Article in English | MEDLINE | ID: mdl-35164529

ABSTRACT

Background: The development of drugs is essential to eradicate tuberculosis. Materials & methods: Sixteen 3,5-dinitrobenzoylhydrazone (2-17) derivatives and their synthetic precursors 3,5-dinitrobenzoylhydrazide (1) and methyl ester (18) were screened for their anti-Mycobacterium tuberculosis (Mtb) potential. Results: Twelve compounds had minimum inhibitory concentration (MIC) ranging from 0.24 to 7.8 µg/ml against the Mtb strain. The activity was maintained in multidrug-resistant Mtb clinical isolates. Only compound (17) showed activity against nontuberculous mycobacteria. The compounds exhibited a limited spectrum of activity, with an MIC >500 µg/ml against Gram-positive and -negative bacteria. Compounds (2), (5) and (11) showed a synergistic effect with rifampicin. An excellent selectivity index value was found, with values reaching 583.33. Conclusion: 3,5-dinitrobenzoylhydrazone derivatives could be considered as a scaffold for the development of antituberculosis drugs.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Antitubercular Agents/pharmacology , Humans , Microbial Sensitivity Tests , Rifampin/pharmacology , Tuberculosis/drug therapy , Tuberculosis/microbiology
3.
Future Microbiol ; 16: 1195-1207, 2021 10.
Article in English | MEDLINE | ID: mdl-34590903

ABSTRACT

Aim: To elucidate the changes in protein expression associated with polymyxin resistance in Klebsiella pneumoniae, we profiled a comparative proteomic analysis of polymyxin B-resistant mutants KPC-2-producing K. pneumoniae, and of its susceptible counterparts. Material & methods: Two-dimensional reversed phase nano ultra-performance liquid chromatography mass spectrometry was used for proteomic analysis. Results: Our results showed that the proteomic profile involved several biological processes, and we highlight the downregulation of outer membrane protein A (OmpA) and the upregulation of SlyB outer membrane lipoprotein (conserved protein member of the PhoPQ regulon) and AcrA multidrug efflux pump in polymyxin B-resistant strains. Conclusion: Our results highlight the possible participation of the SlyB, AcrA and OmpA proteins in the determination of polymyxin B heteroresistance in KPC-2-producing K. pneumoniae.


Subject(s)
Bacterial Proteins/genetics , Klebsiella pneumoniae , Polymyxin B , beta-Lactamases/genetics , Bacterial Outer Membrane Proteins , Drug Resistance, Bacterial , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/genetics , Polymyxin B/pharmacology , Proteomics
4.
Future Microbiol ; 16: 623-633, 2021 06.
Article in English | MEDLINE | ID: mdl-34098743

ABSTRACT

Aim: To evaluate the modulatory effect of piperine (PIP) on streptomycin (SM) activity in Mycobacterium tuberculosis (Mtb). Materials & methods: SM and PIP minimum inhibitory concentration (MIC) and combinatory activity were determined in Mtb H37Rv and in susceptible and resistant clinical isolates. Ethidium bromide accumulation assay and relative quantification of efflux pumps genes (rv1258c, rv1218c and rv2942), after SM and SM+PIP combination exposure, were also performed. Results: PIP concentration of 25 µg/ml (1/4× MIC) was able to inhibit efflux pumps activity, to modulate SM activity in Mtb, and conducted changes in the relative quantification of efflux pumps genes. Conclusion: SM+PIP combination was able to rescue the SM-susceptible MIC values in SM-resistant Mtb.


Subject(s)
Alkaloids/pharmacology , Antitubercular Agents/pharmacology , Benzodioxoles/pharmacology , Mycobacterium tuberculosis/drug effects , Piperidines/pharmacology , Polyunsaturated Alkamides/pharmacology , Streptomycin/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Drug Resistance, Bacterial/drug effects , Drug Synergism , Humans , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Microbial Sensitivity Tests
5.
Braz J Microbiol ; 52(3): 1201-1214, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33929720

ABSTRACT

Endophytes are microorganisms that form symbiotic relationships with their host. These microorganisms can produce a variety of secondary metabolites, some of which have inhibitory effects on pests and pathogens or even act to promote plant growth. Due to these characteristics, these microorganisms are used as sources of biologically active substances for a wide range of biotechnological applications. Based on that, the aim of this study was to evaluate the production of metabolites of the endophytic Aspergillus flavus CL7 isolated from Chromolaena laevigata, in four different cultivation conditions, and to determine the antimicrobial, cytotoxic, antiviral, and antioxidant potential of these extracts. The multiphasic approach used to identify this strain was based on morphology and ITS gene sequence analysis. The chemical investigation of A. flavus using potato dextrose and minimal medium, using both stationary and agitated methods, resulted in the isolation of kojic acid, α-cyclopiazonic acid, and 20,25-dihydroxyaflavinine. Another 18 compounds in these extracts were identified by UHPLC-HRMS/MS, of which dideacetyl parasiticolide A has been described for the first time from A. flavus. Aflatoxins, important chemomarkers of A. flavus, were not detected in any of the extracts, thus indicating that the CL7 strain is non-aflatoxigenic. The biological potential of all extracts was evaluated, and the best results were observed for the extract obtained using minimal medium against Trichophyton rubrum and Mycobacterium tuberculosis.


Subject(s)
Aspergillus flavus/chemistry , Biological Products/chemistry , Chromolaena , Aflatoxins , Aspergillus flavus/genetics , Biological Products/pharmacology , Chromolaena/microbiology , Endophytes
6.
Future Microbiol ; 15: 1527-1534, 2020 10.
Article in English | MEDLINE | ID: mdl-33215538

ABSTRACT

Aim: To evaluate the activity of (-)-camphene-based thiosemicarbazide (TSC) and 4-hydroxy-thiosemicarbazone (4-OH-TSZ), alone and in combination against Gram-positive. Material & methods: MIC were determined for Staphylococcus aureus, Enterococcus spp. reference strains and clinical isolates. Drug combination, time-kill and cytotoxicity assays were also performed. Results: TSC and 4-OH-TSZ demonstrated potent inhibitory activity against S. aureus and Enterococcus spp., including multidrug-resistant isolates (MIC ranging from 1.9 to 31.2 µg/ml), and were bactericidal for the reference strains of both Gram-positive tested. The derivatives proved to be selective for the bacteria and synergistic with oxacillin and vancomycin. Conclusion: (-)-Camphene-based derivatives can represent promising drug candidates against critical pathogens, such as S. aureus and Enterococcus spp., including MRSA and vancomycin resistance Enterococcus spp. isolates.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bicyclic Monoterpenes/pharmacology , Enterococcus/drug effects , Staphylococcus aureus/drug effects , Thiosemicarbazones/pharmacology , Anti-Bacterial Agents/chemistry , Drug Resistance, Multiple, Bacterial , Enterococcus/growth & development , Gram-Positive Bacterial Infections/microbiology , Humans , Microbial Sensitivity Tests , Staphylococcal Infections/microbiology , Staphylococcus aureus/growth & development , Thiosemicarbazones/chemistry , Vancomycin/pharmacology
7.
Future Med Chem ; 12(17): 1533-1546, 2020 09.
Article in English | MEDLINE | ID: mdl-32820960

ABSTRACT

Aim: Eight coumarin derivatives (1a-h) obtained from natural (-)-mammea A/BB (1) and 13 synthetic coumarins (2-14) had their cytotoxicity and biological activity evaluated against Mycobacterium tuberculosis H37Rv reference strain and multidrug-resistant clinical isolates. Materials & methods: Anti-M. tuberculosis activity was evaluated by resazurin microtiter assay plate, and the cytotoxicity of natural and synthetic products using J774A.1 macrophages by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Results: Compounds 1g, 5, 6, 12 and 14 were more active against M. tuberculosis H37Rv and multidrug-resistant clinical isolates with MIC values ranging from 15.6 to 62.5 µg/ml. Conclusion: These results demonstrate that the coumarin derivatives were active against multidrug-resistant clinical isolates, becoming potential candidates to be used in the treatment of resistant tuberculosis.


Subject(s)
Antitubercular Agents/pharmacology , Biological Products/pharmacology , Coumarins/pharmacology , Mycobacterium tuberculosis/drug effects , Animals , Antitubercular Agents/chemical synthesis , Antitubercular Agents/chemistry , Biological Products/chemical synthesis , Biological Products/chemistry , Calophyllum/chemistry , Cells, Cultured , Coumarins/chemical synthesis , Coumarins/chemistry , Macrophages/drug effects , Mice , Microbial Sensitivity Tests , Molecular Structure , Plant Extracts
8.
Future Microbiol ; 15: 723-738, 2020 06.
Article in English | MEDLINE | ID: mdl-32686961

ABSTRACT

Aim: To evaluate the activity, cytotoxicity and efflux pumps inhibition of a series of 12 novels (-)-camphene-based 1,3,4-thiadiazoles (TDZs) against Mycobacterium tuberculosis (Mtb). Materials & methods: The minimum inhibitory concentration (MIC), cytotoxicity for three cell lines, ethidium bromide accumulation and checkerboard methods were carried out. Results: Compounds (6a, 6b, 6c, 6g, 6h and 6j) showed significant anti-Mtb activity (MIC 3.9-7.8 µg/ml) and no antagonism with anti-TB drugs already used in the TB treatment. Selectivity index (SI) was also determined, with values reaching 42.9 for H37Rv strain and 97.1 for clinical isolate. Five compounds also showed bacterial efflux pumps inhibition and one showed modulator effect with three drugs. Conclusion: These six TDZs should be considered as new scaffolds to develop anti-TB drugs.


Subject(s)
Antitubercular Agents/pharmacology , Mycobacterium tuberculosis/drug effects , Thiadiazoles/pharmacology , Animals , Bacterial Outer Membrane Proteins/drug effects , Blood Cells/drug effects , Chlorocebus aethiops , Drug Discovery , Drug Synergism , Humans , Macrophages/drug effects , Microbial Sensitivity Tests , Sheep/blood , Terpenes/pharmacology , Thiadiazoles/chemical synthesis , Thiadiazoles/toxicity , Tuberculosis/drug therapy , Vero Cells/drug effects
9.
Future Microbiol ; 15: 107-114, 2020 01.
Article in English | MEDLINE | ID: mdl-32064924

ABSTRACT

Aim: To evaluate an assay to detect minimum bactericidal concentration (MBC) in Mycobacterium tuberculosis, using as single model rifampicin, isoniazid, levofloxacin (LVX) and linezolid (LNZ) and in combination. Material & methods: MBCs were carried out directly from resazurin microtiter assay plate and 3D checkerboard in M. tuberculosis H37Rv and five resistant clinical isolates. Results: The proposed MBC assay showed similar values to those determined by MGIT™, used as control. LVX and LNZ's MBC values were close to their MIC values. LNZ or LVX combined with isoniazid and rifampicin showed MBC value reduced in 63.7% of the assays. Conclusion: The proposed assay to determine MBCs of drugs can be applied to the study of new compounds with anti-M. tuberculosis activity to detect their bactericidal effect and also in laboratory routine for clinical dose adjustment of drugs according to the patient's profile.


Subject(s)
Antitubercular Agents/pharmacology , Mycobacterium tuberculosis/drug effects , Tuberculosis/drug therapy , Drug Resistance, Multiple, Bacterial , Drug Synergism , Humans , Isoniazid/pharmacology , Levofloxacin/pharmacology , Linezolid/pharmacology , Microbial Sensitivity Tests , Rifampin/pharmacology
10.
Future Microbiol ; 14: 981-994, 2019 07.
Article in English | MEDLINE | ID: mdl-31382801

ABSTRACT

Aim: To evaluate the potential of three benzohydrazones (1-3), four acylhydrazones derived from isoniazid (INH-acylhydrazones) (4-7) and one hydrazone (8) as antituberculosis agents. Materials & methods: Inhibitory and bactericidal activities were determined for the reference Mycobacterium tuberculosis (Mtb) strain and clinical isolates. Cytotoxicity, drug combinations and ethidium bromide accumulation assays were also performed. Results: The tested compounds (1-8) presented excellent antituberculosis activity with surprisingly inhibitory (0.12-250 µg/ml) and bactericidal values, even against multidrug-resistant Mtb clinical isolates. Compounds showed high selectivity index, with values reaching 1833.33, and a limited spectrum of activity. Some of the compounds (2 & 8) are also great inhibitors of bacillus efflux pumps. Conclusion: Benzohydrazones and INH-acylhydrazones may be considered scaffolds for the development of new anti-Mtb drugs.


Subject(s)
Antitubercular Agents/pharmacology , Hydrazones/pharmacology , Isoniazid/pharmacology , Mycobacterium tuberculosis/drug effects , Animals , Antitubercular Agents/chemical synthesis , Antitubercular Agents/chemistry , Cell Line, Tumor , Chlorocebus aethiops , Drug Resistance, Multiple, Bacterial/drug effects , Ethidium/metabolism , HeLa Cells , Humans , Hydrazones/chemical synthesis , Hydrazones/chemistry , Isoniazid/chemical synthesis , Isoniazid/chemistry , Microbial Sensitivity Tests , Molecular Structure , Mycobacterium tuberculosis/isolation & purification , Tuberculosis/microbiology , Vero Cells
11.
Future Microbiol ; 14: 331-344, 2019 03.
Article in English | MEDLINE | ID: mdl-30757916

ABSTRACT

AIM: To evaluate (i) the in vitro activity of eugenol (EUG) and three derivatives against Mycobacterium tuberculosis (Mtb), nontuberculous mycobacteria (NTM) and other bacteria, (ii) the EUG and antituberculosis drugs combinatory effect and (iii) the EUG and its derivatives cytotoxicity. MATERIALS & METHODS: Minimum inhibitory concentration of the compounds were determined by resazurin microtiter or broth microdilution assay and the drug interaction between EUG and antituberculosis drugs by resazurin drug combination microtiter. The cytotoxicity was carried out in macrophages, HeLa and VERO cells. Results: EUG and derivatives displayed activity and synergic effect of EUG combined with rifampicin, isoniazid, ethambutol, and pyrazinamide in Mtb including multidrug-resistant isolates, with more selectivity to bacillus than macrophages, HeLa and VERO cells (selective index from 0.65 to 31.4). EUG derivatives (4-allyl-2-methoxyphenyl acetate, 4-allyl-2-methoxyphenyl benzoate, and 4-allyl-2-methoxyphenyl 4-nitrobenzoate) were more active against nontuberculous mycobacteria than EUG. EUG and derivatives exhibited low activity in other Gram-positive and -negative bacteria. CONCLUSION: EUG and its derivatives show activity against Mycobacterium spp. and synergic effect of EUG combined with antituberculosis drugs against Mtb.


Subject(s)
Antitubercular Agents/pharmacology , Eugenol/chemistry , Eugenol/pharmacology , Mycobacterium tuberculosis/drug effects , Nontuberculous Mycobacteria/drug effects , Animals , Chlorocebus aethiops , Humans , Microbial Sensitivity Tests , Vero Cells
13.
Future Microbiol ; 14: 185-194, 2019 02.
Article in English | MEDLINE | ID: mdl-30648892

ABSTRACT

AIM: To evaluate modulatory effect of verapamil (VP) in rifampicin (RIF) activity and its effect in efflux pumps (EPs) transcript levels in Mycobacterium tuberculosis. MATERIALS & METHODS: RIF and VP minimal inhibitory concentration, combinatory effect and detection of mutations were determined in 16 isolates. EPs transcript levels were determined in four isolates by real-time PCR after exposure to drugs. RESULTS: VP showed good combinatory effect among RIF-resistant isolates. This effect was also observed in the relative transcript levels of EPs, mainly after 72 h of exposure, depending on the EP gene, genotype and the resistance profile of the isolate. CONCLUSION: Additional regulatory mechanisms in the EP activities, as well as, interactions with other drug-specific resistance mechanisms need further investigation in M. tuberculosis.


Subject(s)
Antitubercular Agents/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Mycobacterium tuberculosis/drug effects , Rifampin/pharmacology , Verapamil/pharmacology , Bacterial Proteins/drug effects , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Brazil , Catalase/genetics , DNA-Directed RNA Polymerases/genetics , Drug Synergism , Drug Therapy, Combination , Gene Expression Regulation, Bacterial , Genotype , Humans , Membrane Transport Proteins/drug effects , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Microbial Sensitivity Tests , Mutation , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/metabolism , Oxidoreductases/genetics , Time Factors , Tuberculosis, Multidrug-Resistant/microbiology
14.
Infect Disord Drug Targets ; 19(1): 73-80, 2019.
Article in English | MEDLINE | ID: mdl-29366429

ABSTRACT

BACKGROUND: In recent years, very few effective drugs against Mycobacterium tuberculosis have emerged, which motivates the research with drugs already used in the treatment of tuberculosis. Ethambutol is a bacteriostatic drug that affects cell wall integrity, but the effects of this drug on bacilli are not fully exploited. OBJECTIVE: Based on the need to better investigate the complex mechanism of action of ethambutol, our study presented the proteome profile of M. tuberculosis after different times of ethambutol exposure, aiming to comprehend the dynamics of bacilli response to its effects. M. tuberculosis was exposed to ½ MIC of ethambutol at 24 and 48 hours. The proteins were identified by MALDI-TOF/TOF. RESULTS: The main protein changes occurred in metabolic proteins as dihydrolipoyl dehydrogenase (Rv0462), glutamine synthetase1 (Rv2220), electron transfer flavoprotein subunit beta (Rv3029c) and adenosylhomocysteinase (Rv3248c). CONCLUSION: Considering the functions of these proteins, our results support that the intermediary metabolism and respiration were affected by ethambutol and this disturbance provided proteins that could be explored as additional targets for this drug.


Subject(s)
Antitubercular Agents/pharmacology , Bacterial Proteins/metabolism , Ethambutol/pharmacology , Mycobacterium tuberculosis/drug effects , Tuberculosis/drug therapy , Antitubercular Agents/therapeutic use , Cell Wall/drug effects , Ethambutol/therapeutic use , Humans , Metabolic Networks and Pathways/drug effects , Microbial Sensitivity Tests/methods , Mycobacterium tuberculosis/metabolism , Proteome/drug effects , Proteome/isolation & purification , Time Factors , Tuberculosis/microbiology
15.
Nat Prod Res ; 33(23): 3372-3377, 2019 Dec.
Article in English | MEDLINE | ID: mdl-29792346

ABSTRACT

In this work the aim of study was the synthesis and evaluation of in vitro anti-Mycobacterium tuberculosis activity as well as the cytotoxicity in VERO cells of a series of 17 novel thiosemicarbazones derived from the natural monoterpene (-)-camphene by REMA and MTT methods. Overall, the majority of tested compounds exhibited considerable inhibitory effects on the growth of M. tuberculosis H37Rv, especially the derivatives 3, 4a-c, 4f, 4i, 4k, 5 and 6a-b. MIC values of 20 tested compounds ranged from 3.9 to > 250 µg/mL. It was found that when inserting new nitrogenous groups to the (-)-camphene increased the anti-M. tuberculosis activity of some compounds. The SI was calculated for all compounds that showed highly potent anti-M. tuberculosis activity and the best SI values were 21.36, 26.92 and 31.62 (4b, 6a and 6b), and may be considered potential candidates for future antituberculosis drugs.


Subject(s)
Antitubercular Agents/chemical synthesis , Antitubercular Agents/pharmacology , Mycobacterium tuberculosis/drug effects , Thiosemicarbazones/chemical synthesis , Thiosemicarbazones/pharmacology , Animals , Bicyclic Monoterpenes/chemistry , Chlorocebus aethiops , Microbial Sensitivity Tests , Structure-Activity Relationship , Vero Cells
16.
Future Microbiol ; 13: 877-888, 2018 06 01.
Article in English | MEDLINE | ID: mdl-29877104

ABSTRACT

AIM: Evaluating carvacrol, derivatives and carvacrol plus anti-TB (anti-tuberculous) drug combination activities in Mycobacterium tuberculosis as well as carvacrol cytotoxicity, efflux pump inhibitor activity and morphological changes in M. tuberculosis H37Rv. METHODS: Carvacrol (CAR) and derivatives' activities were determined by resazurin microtiter assay and drug interaction by resazurin drug combination microtiter. Carvacrol cytotoxicity in VERO cells and efflux pumps inhibitor activity by ethidium bromide assay were determined and scanning electron microscopy performed. RESULTS: Carvacrol MIC ranged from 19 to 156 µg/ml and carvacrol plus rifampicin combination showed synergistic effect in clinical isolates. No anti-M. tuberculosis activity improvement was observed with carvacrol derivatives. Carvacrol showed to be selective for M. tuberculosis, to have efflux pumps activity and to induce rough bacillary and agglomerates. CONCLUSION: Carvacrol shows good anti-M. tuberculosis activity and synergism with rifampicin.


Subject(s)
Antitubercular Agents/pharmacology , Monoterpenes/pharmacology , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/growth & development , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cymenes , Humans , Microbial Sensitivity Tests , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/metabolism , Rifampin/pharmacology , Tuberculosis/microbiology
17.
Future Microbiol ; 12: 867-879, 2017 08.
Article in English | MEDLINE | ID: mdl-28686056

ABSTRACT

AIM: We investigated a proteome profile, protein-protein interaction and morphological changes of Mycobacterium tuberculosis after different times of eupomatenoid-5 (EUP-5) induction to evaluate the cellular response to the drug-induced damages. METHODS: The bacillus was induced to sub-minimal inhibitory concentration of EUP-5 at 12 h, 24 h and 48 h. The proteins were separated by 2D gel electrophoresis, identified by LC/MS-MS. Scanning electron microscopy and Search Tool for the Retrieval of Interacting Genes/Proteins analyses were performed. RESULTS: EUP-5 impacts mainly in M. tuberculosis proteins of intermediary metabolism and interactome suggests a multisite disturbance that contributes to bacilli death. Scanning electron microscopy revealed the loss of bacillary form. CONCLUSION: Some of the differentially expressed proteins have the potential to be drug targets such as citrate synthase (Rv0896), phosphoglycerate kinase (Rv1437), ketol-acid reductoisomerase (Rv3001c) and ATP synthase alpha chain (Rv1308).


Subject(s)
Benzofurans/pharmacology , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/metabolism , Phenols/pharmacology , Proteomics , Bacterial Proteins/drug effects , Bacterial Proteins/metabolism , Benzofurans/chemistry , Citrate (si)-Synthase/drug effects , Electrophoresis, Gel, Two-Dimensional , Genes, Bacterial/drug effects , Humans , Ketol-Acid Reductoisomerase/drug effects , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Mycobacterium tuberculosis/cytology , Mycobacterium tuberculosis/enzymology , Phenols/chemistry , Phosphoglycerate Kinase/drug effects , Protein Interaction Domains and Motifs , Proteome/analysis , Tandem Mass Spectrometry , Time Factors , Tuberculosis/drug therapy , Tuberculosis/microbiology
18.
Future Microbiol ; 11: 1123-32, 2016 09.
Article in English | MEDLINE | ID: mdl-27545345

ABSTRACT

AIM: To study the proteomic and morphological changes in Mycobacterium tuberculosis H37Rv exposed to subinhibitory concentration of isoniazid (INH). MATERIALS & METHODS: The bacillus was exposed to ½ MIC of INH at 12, 24 and 48 h. The samples' cells were submitted to scanning electron microscopy. The proteins were separated by 2D gel electrophoresis and identified by MS. RESULTS: INH exposure was able to alter the format, the multiplication and causing a cell swelling in the bacillus. The major altered proteins were related to the virulence, detoxification, adaptation, intermediary metabolism and lipid metabolism. CONCLUSION: The protein and morphological changes in M. tuberculosis induced by ½ MIC INH were related to defense mechanism of the bacillus or the action of INH therein.


Subject(s)
Antitubercular Agents/pharmacology , Bacterial Proteins/chemistry , Isoniazid/pharmacology , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/growth & development , Tuberculosis/microbiology , Antitubercular Agents/analysis , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Electrophoresis, Gel, Two-Dimensional , Humans , Isoniazid/analysis , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/metabolism , Proteomics
19.
Tuberculosis (Edinb) ; 97: 65-72, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26980498

ABSTRACT

The aim of the present study was to (i) evaluate the in vitro action of rifampicin (RIF), ethambutol or isoniazid with efflux pumps inhibitors (EPIs) in Mycobacterium tuberculosis (Mtb) H37Rv and (ii) evaluate the morphological and efflux pumps (EPs) transcriptional changes by the action of rifampicin + verapamil combination (RIF + VP). The minimal inhibitory concentration and synergic effect of drug combinations were determined by Resazurin Microtiter Plate Assay and Resazurin Drugs Combination Microtiter Assay, respectively. VP showed greater capacity of ethidium bromide accumulation and RIF + VP had the lower fractional inhibitory concentration index. The RIF + VP exerted a similar reduction of viable cell counts to RIF by time-kill curve, but decreases in the expression of EPs genes were observed by Real time PCR at 72 h of RIF + VP exposure. Accumulative morphological changes (wrinkled and rounding) caused by each drug were observed by scanning electron microscopy after RIF + VP exposure. The downexpression of EPs related genes exposed to RIF + VP, suggest an effective inhibitory activity of VP in Mtb H37Rv. The role of EPs and the use of EPIs open up a powerful approach and the RIF + VP combination should be studied in Mtb more thoroughly.


Subject(s)
Antibiotics, Antitubercular/pharmacology , Bacterial Proteins/drug effects , Membrane Transport Proteins/drug effects , Mycobacterium tuberculosis/drug effects , Rifampin/pharmacology , Verapamil/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Dose-Response Relationship, Drug , Drug Therapy, Combination , Gene Expression Regulation, Bacterial/drug effects , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Microbial Viability , Microscopy, Electron, Scanning , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/metabolism , Mycobacterium tuberculosis/ultrastructure , Time Factors , Transcription, Genetic/drug effects
20.
Curr Pharm Biotechnol ; 17(6): 532-9, 2016.
Article in English | MEDLINE | ID: mdl-26778457

ABSTRACT

The conventional techniques used to extract natural products have many disadvantages, and alternative methods have been used, such as supercritical fluid extraction (SFE-CO2). We compared the anti-Mycobacterium tuberculosis activity and cytotoxicity of extracts and major pure compounds were obtained from the leaves of Calophyllum brasiliense by SFE-CO2, maceration and Soxhlet. Anti-M tuberculosis activity was evaluated by resazurin microtiter assay plate and cytotoxicity assay was performed using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide. The (-) mammea A/BB, (-) mammea B/BB, mammea B/BB cyclo D, ponnalide, mammea A/BA cyclo D, and amentoflavone were identified as the majority compounds. SFE-CO2, especially at 313 K and 10.92 MPa showed better yield for (-) mammea A/BB. Anti-M. tuberculosis activity (62.5 µg/mL) and cytotoxicity (Selectivity Index = 0.320-0.576) were similar for the three extracts. Mammea B/BB cyclo D had a minimum inhibitory concentration (MIC) of 125 µg/mL, and ponnalide and mammea A/BA cyclo D had MICs > 250 µg/mL. The pure compounds isolated showed low Selectivity Index (< 0.09). SFE-CO2 may be more promising than conventional methods for the extraction of compound (-) mammea A/BB, which presented the best anti-M. tuberculosis activity in our previous study. This is important for current industrial requirements to obtain extracts from medicinal plants using clean technologies.


Subject(s)
Antitubercular Agents/pharmacology , Calophyllum , Mycobacterium tuberculosis/drug effects , Plant Extracts/pharmacology , Antitubercular Agents/chemistry , Biflavonoids/analysis , Biflavonoids/pharmacology , Chromatography, Supercritical Fluid , Coumarins/analysis , Coumarins/pharmacology , Microbial Sensitivity Tests , Mycobacterium tuberculosis/growth & development , Plant Extracts/chemistry , Plant Leaves
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