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Diedericks B, Kok AM, Mandiwana V, Lall N. A Review of the Potential of Poly-(lactide-co-glycolide) Nanoparticles as a Delivery System for an Active Antimycobacterial Compound, 7-Methyljuglone. Pharmaceutics 2024; 16:216. [PMID: 38399270 PMCID: PMC10893214 DOI: 10.3390/pharmaceutics16020216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/15/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
7-Methyljuglone (7-MJ) is a pure compound isolated from the roots of Euclea natalensis A. DC., a shrub indigenous to South Africa. It exhibits significant promise as a potential treatment for the highly communicable disease tuberculosis (TB), owing to its effective antimycobacterial activity against Mycobacterium tuberculosis. Despite its potential therapeutic benefits, 7-MJ has demonstrated in vitro cytotoxicity against various cancerous and non-cancerous cell lines, raising concerns about its safety for consumption by TB patients. Therefore, this review focuses on exploring the potential of poly-(lactide-co-glycolic) acid (PLGA) nanoparticles as a delivery system, which has been shown to decrease in vitro cytotoxicity, and 7-MJ as an effective antimycobacterial compound.
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Affiliation(s)
- Bianca Diedericks
- Department of Plant and Soil Sciences, University of Pretoria, Pretoria 0002, South Africa; (B.D.); (A.-M.K.)
| | - Anna-Mari Kok
- Department of Plant and Soil Sciences, University of Pretoria, Pretoria 0002, South Africa; (B.D.); (A.-M.K.)
- Research Fellow, South African International Maritime Institute (SAIMI), Nelson Mandela University, Gqeberha 6019, South Africa
| | - Vusani Mandiwana
- Chemicals Cluster, Centre for Nanostructures and Advanced Materials, Council for Scientific and Industrial Research, Pretoria 0001, South Africa;
| | - Namrita Lall
- Department of Plant and Soil Sciences, University of Pretoria, Pretoria 0002, South Africa; (B.D.); (A.-M.K.)
- School of Natural Resources, University of Missouri, Columbia, MO 65211, USA
- College of Pharmacy, JSS Academy of Higher Education and Research, Mysuru 643001, India
- Senior Research Fellow, Bio-Tech R&D Institute, University of the West Indies, Kingston IAU-016615, Jamaica
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Pujari V, Rozman K, Dhiman RK, Aldrich CC, Crick DC. Mycobacterial MenG: Partial Purification, Characterization, and Inhibition. ACS Infect Dis 2022; 8:2430-2440. [PMID: 36417754 DOI: 10.1021/acsinfecdis.2c00190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Menaquinone (MK) is an essential component of the electron transport chain (ETC) in the gram-variable Mycobacterium tuberculosis and many Gram-positive pathogens. Three genes in the M. tuberculosis genome were annotated as methyltransferases involved in lipoquinone synthesis in mycobacteria. Heterologous expression of Rv0558 complemented an ubiE (the quinone C-methyltransferase involved in ubiquinone and menaquinone synthesis) deletion in Escherichia coli, and expression in a wild-type E. coli strain increased quinone C-methyltransferase specific activity by threefold. Rv0558 encodes a canonical C-methyltransferase or, more specifically, a S-adenosylmethionine/demethylmenaquinol methyltransferase. Partially purified recombinant protein catalyzed the formation of MK from demethylmenaquinone (DMK), although the activity of the recombinant protein was low and appeared to require a cofactor or intact membrane structure for activity. Membrane preparations from irradiated M. tuberculosis also showed poor activity; however, membrane preparations from wild-type Mycobacterium smegmatis showed robust, substrate-dependent activity. The apparent Km values for demethylmenaquinone and SAM were 14 ± 5.0 and 17 ± 7.0 μM, respectively. Interestingly, addition of dithiothreitol, dithionite, NADH, or other substrates of primary dehydrogenases to reaction mixtures containing membrane preparations stimulated the activity. Thus, these observations strongly suggest that demethylmenaquinol is the actual substrate of MenG. Ro 48-8071, previously reported to inhibit mycobacterial MK synthesis and growth, inhibited Rv0558 activity with an IC50 value of 5.1 ± 0.5 μM, and DG70 (GSK1733953A), first described as a respiration inhibitor in M. tuberculosis, inhibits MenG activity with an IC50 value of 2.6 ± 0.6 μM.
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Affiliation(s)
- Venugopal Pujari
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Kaja Rozman
- Department of Medicinal Chemistry, University of Minnesota, 308 Harvard Street Southeast, Minneapolis, Minnesota 55455, United States
| | - Rakesh K Dhiman
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Courtney C Aldrich
- Department of Medicinal Chemistry, University of Minnesota, 308 Harvard Street Southeast, Minneapolis, Minnesota 55455, United States
| | - Dean C Crick
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523, United States
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Dechow SJ, Coulson GB, Wilson MW, Larsen SD, Abramovitch RB. AC2P20 selectively kills Mycobacterium tuberculosis at acidic pH by depleting free thiols. RSC Adv 2021; 11:20089-20100. [PMID: 34168865 PMCID: PMC8176622 DOI: 10.1039/d1ra03181c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) senses and adapts to host immune cues as part of its pathogenesis. One environmental cue sensed by Mtb is the acidic pH of its host niche in the macrophage phagosome. Disrupting the ability of Mtb to sense and adapt to acidic pH has the potential to reduce survival of Mtb in macrophages. Previously, a high throughput screen of a ∼220 000 compound small molecule library was conducted to discover chemical probes that inhibit Mtb growth at acidic pH. The screen discovered chemical probes that kill Mtb at pH 5.7 but are inactive at pH 7.0. In this study, AC2P20 was prioritized for continued study to test the hypothesis that it was targeting Mtb pathways associated with pH-driven adaptation. RNAseq transcriptional profiling studies showed AC2P20 modulates expression of genes associated with redox homeostasis. Gene enrichment analysis revealed that the AC2P20 transcriptional profile had significant overlap with a previously characterized pH-selective inhibitor, AC2P36. Like AC2P36, we show that AC2P20 kills Mtb by selectively depleting free thiols at acidic pH. Mass spectrometry studies show the formation of a disulfide bond between AC2P20 and reduced glutathione, supporting a mechanism where AC2P20 is able to deplete intracellular thiols and dysregulate redox homeostasis. The observation of two independent molecules targeting free thiols to kill Mtb at acidic pH further supports that Mtb has restricted redox homeostasis and sensitivity to thiol-oxidative stress at acidic pH.
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Affiliation(s)
- Shelby J Dechow
- Department of Microbiology and Molecular Genetics, Michigan State University East Lansing MI 48824 USA +1 517 353-8957 +1 517 884-5416
| | - Garry B Coulson
- Department of Microbiology and Molecular Genetics, Michigan State University East Lansing MI 48824 USA +1 517 353-8957 +1 517 884-5416
| | - Michael W Wilson
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan Ann Arbor MI 48109 USA
| | - Scott D Larsen
- Vahlteich Medicinal Chemistry Core, College of Pharmacy, University of Michigan Ann Arbor MI 48109 USA
| | - Robert B Abramovitch
- Department of Microbiology and Molecular Genetics, Michigan State University East Lansing MI 48824 USA +1 517 353-8957 +1 517 884-5416
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Sartor P, Bock J, Hennecke U, Thierbach S, Fetzner S. Modification of the Pseudomonas aeruginosa toxin 2-heptyl-1-hydroxyquinolin-4(1H)-one and other secondary metabolites by methyltransferases from mycobacteria. FEBS J 2020; 288:2360-2376. [PMID: 33064871 DOI: 10.1111/febs.15595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 09/22/2020] [Accepted: 10/12/2020] [Indexed: 11/26/2022]
Abstract
The opportunistic pathogen Pseudomonas aeruginosa, one of the most prevalent species in infections of the cystic fibrosis lung, produces a range of secondary metabolites, among them the respiratory toxin 2-heptyl-1-hydroxyquinolin-4(1H)-one (2-heptyl-4-hydroxyquinoline N-oxide, HQNO). Cultures of the emerging cystic fibrosis pathogen Mycobacteroides abscessus detoxify HQNO by methylating the N-hydroxy moiety. In this study, the class I methyltransferase MAB_2834c and its orthologue from Mycobacterium tuberculosis, Rv0560c, were identified as HQNO O-methyltransferases. The P. aeruginosa exoproducts 4-hydroxyquinolin-2(1H)-one (DHQ), 2-heptylquinolin-4(1H)-one (HHQ), and 2-heptyl-3-hydroxyquinolin-4(1H)-one (the 'Pseudomonas quinolone signal', PQS), some structurally related (iso)quinolones, and the flavonol quercetin were also methylated; however, HQNO was by far the preferred substrate. Both enzymes converted a benzimidazole[1,2-a]pyridine-4-carbonitrile-based compound, representing the scaffold of antimycobacterial substances, to an N-methylated derivative. We suggest that these promiscuous methyltransferases, newly termed as heterocyclic toxin methyltransferases (Htm), are involved in cellular response to chemical stress and possibly contribute to resistance of mycobacteria toward antimicrobial natural compounds as well as drugs. Thus, synthetic antimycobacterial agents may be designed to be unamenable to methyl transfer. ENZYMES: S-adenosyl-l-methionine:2-heptyl-1-hydroxyquinolin-4(1H)-one O-methyl-transferase, EC 2.1.1.
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Affiliation(s)
- Pascal Sartor
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Germany
| | - Jonathan Bock
- Organic Chemistry Research Group, Department of Chemistry and Department of Bioengineering Sciences, Vrije Universiteit Brussels, Belgium
| | - Ulrich Hennecke
- Organic Chemistry Research Group, Department of Chemistry and Department of Bioengineering Sciences, Vrije Universiteit Brussels, Belgium
| | - Sven Thierbach
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Germany
| | - Susanne Fetzner
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Germany
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Gamngoen R, Putim C, Salee P, Phunpae P, Butr-Indr B. A comparison of Rv0559c and Rv0560c expression in drug-resistant Mycobacterium tuberculosis in response to first-line antituberculosis drugs. Tuberculosis (Edinb) 2017. [PMID: 29523329 DOI: 10.1016/j.tube.2017.11.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Drug resistance to Mycobacterium tuberculosis is a major health problem worldwide. Mycobacterium tuberculosis can progress to be mono-drug resistant or multi-drug resistant by improper treatment. The chemical stress of M. tuberculosis was performed in this study. Rv0559c is an unknown secreted protein. Rv0560c is a putative benzoquinone methyltransferase of M. tuberculosis cell. Rv0559c gene is located downstream of Rv0560c gene. Both genes respond to salicylate stress. Drug susceptible, isoniazid resistant, rifampicin resistant and multi-drug resistant phenotypes of M. tuberculosis clinical isolates were used to determine the expression of Rv0559c and Rv0560c by qRT-PCR. In all of mycobacteria strains there was up-regulation in both genes when stressed with isoniazid. This study determined the expression of both genes, which may play important roles in the drug resistance mechanism of mycobacteria.
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Affiliation(s)
- Ratikorn Gamngoen
- Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Chanyanuch Putim
- Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Parichat Salee
- Division of Infectious Diseases, Department of Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Ponrut Phunpae
- Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Bordin Butr-Indr
- Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand.
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Kokoczka R, Schuessler DL, Early JV, Parish T. Mycobacterium tuberculosis Rv0560c is not essential for growth in vitro or in macrophages. Tuberculosis (Edinb) 2016; 102:3-7. [PMID: 28061949 DOI: 10.1016/j.tube.2016.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 11/02/2016] [Accepted: 11/03/2016] [Indexed: 12/29/2022]
Abstract
Mycobacterium tuberculosis Rv0560c, a putative benzoquinone methyl transferase, is heavily induced in response to salicylate exposure. It has some similarity to Escherichia coli UbiG, although its role in ubiquinone or menaquinone synthesis is not clear, since M. tuberculosis is not known to produce ubiquinone. We constructed an unmarked in-frame deletion of Rv0560c in M. tuberculosis to determine its role in vitro. Deletion of Rv0560c in M. tuberculosis had no effect on growth in medium containing salicylate or in its ability to grow in macrophages. In addition, no change to compound sensitivity, as determined by minimum inhibitory concentrations, for a range of compounds targeting respiration was noted. Plumbagin, ethambutol and CCCP had the same minimum bactericidal concentration against the deletion and wild-type strains. Taken together these data show that Rv0560c is dispensable under in vitro conditions in both axenic and macrophage culture and suggest that the role of Rv0560c may be in an alternate biosynthetic pathway of menaquinone which is only used under specific growth conditions.
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Affiliation(s)
- Rachel Kokoczka
- TB Discovery Research, Infectious Disease Research Institute, 1616 Eastlake Ave E, Suite 400, Seattle, WA, 98102, United States
| | - Dorothée L Schuessler
- Queen Mary University of London, Barts and the London School of Medicine and Dentistry, London, E1 2AD, UK
| | - Julie V Early
- TB Discovery Research, Infectious Disease Research Institute, 1616 Eastlake Ave E, Suite 400, Seattle, WA, 98102, United States
| | - Tanya Parish
- TB Discovery Research, Infectious Disease Research Institute, 1616 Eastlake Ave E, Suite 400, Seattle, WA, 98102, United States; Queen Mary University of London, Barts and the London School of Medicine and Dentistry, London, E1 2AD, UK.
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Effects of Lipid-Lowering Drugs on Vancomycin Susceptibility of Mycobacteria. Antimicrob Agents Chemother 2016; 60:6193-9. [PMID: 27503643 DOI: 10.1128/aac.00872-16] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 07/17/2016] [Indexed: 12/24/2022] Open
Abstract
Tuberculosis is still a cause of major concern, partly due to the emergence of multidrug-resistant strains. New drugs are therefore needed. Vancomycin can target mycobacteria with cell envelope deficiency. In this study, we used a vancomycin susceptibility assay to detect drugs hampering lipid synthesis in Mycobacterium bovis BCG and in Mycobacterium tuberculosis We tested three drugs already used to treat human obesity: tetrahydrolipstatin (THL), simvastatin, and fenofibrate. Only vancomycin and THL were able to synergize on M. bovis BCG and on M. tuberculosis, although mycobacteria could also be inhibited by simvastatin alone. Lipid analysis allowed us to identify several lipid modifications in M. tuberculosis H37Rv treated with those drugs. THL treatment mainly reduced the phthiocerol dimycocerosate (PDIM) content in the mycobacterial cell wall, providing an explanation for the synergy, since PDIM deficiency has been related to vancomycin susceptibility. Proteomic analysis suggested that bacteria treated with THL, in contrast to bacteria treated with simvastatin, tried to recover, inducing, among other reactions, lipid synthesis. The combination of THL and vancomycin should be considered a promising solution in developing new strategies to treat multidrug-resistant tuberculosis.
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Mutation of Rv2887, a marR-like gene, confers Mycobacterium tuberculosis resistance to an imidazopyridine-based agent. Antimicrob Agents Chemother 2015; 59:6873-81. [PMID: 26303802 DOI: 10.1128/aac.01341-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/14/2015] [Indexed: 02/05/2023] Open
Abstract
Drug resistance is a major problem in Mycobacterium tuberculosis control, and it is critical to identify novel drug targets and new antimycobacterial compounds. We have previously identified an imidazo[1,2-a]pyridine-4-carbonitrile-based agent, MP-III-71, with strong activity against M. tuberculosis. In this study, we evaluated mechanisms of resistance to MP-III-71. We derived three independent M. tuberculosis mutants resistant to MP-III-71 and conducted whole-genome sequencing of these mutants. Loss-of-function mutations in Rv2887 were common to all three MP-III-71-resistant mutants, and we confirmed the role of Rv2887 as a gene required for MP-III-71 susceptibility using complementation. The Rv2887 protein was previously unannotated, but domain and homology analyses suggested it to be a transcriptional regulator in the MarR (multiple antibiotic resistance repressor) family, a group of proteins first identified in Escherichia coli to negatively regulate efflux pumps and other mechanisms of multidrug resistance. We found that two efflux pump inhibitors, verapamil and chlorpromazine, potentiate the action of MP-III-71 and that mutation of Rv2887 abrogates their activity. We also used transcriptome sequencing (RNA-seq) to identify genes which are differentially expressed in the presence and absence of a functional Rv2887 protein. We found that genes involved in benzoquinone and menaquinone biosynthesis were repressed by functional Rv2887. Thus, inactivating mutations of Rv2887, encoding a putative MarR-like transcriptional regulator, confer resistance to MP-III-71, an effective antimycobacterial compound that shows no cross-resistance to existing antituberculosis drugs. The mechanism of resistance of M. tuberculosis Rv2887 mutants may involve efflux pump upregulation and also drug methylation.
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Kim SJ, Hong M, Song KD, Lee HK, Ryoo S, Heo TH. Normalization of the levels of inflammatory molecules in Mycobacterium smegmatis-infected U937 cells by fibrate pretreatment. Biol Res 2014; 47:42. [PMID: 25299393 PMCID: PMC4177238 DOI: 10.1186/0717-6287-47-42] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 09/05/2014] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Tuberculosis (TB) is a respiratory tract disease caused by Mycobacterium tuberculosis infection. M. tuberculosis exploits immune privilege to grow and divide in pleural macrophages. Fibrates are associated with the immune response and control lipid metabolism through glycolysis with β-oxidation of fatty acids. RESULTS In this study, we investigated the effect of fibrate pretreatment on the immune response during M. smegmatis infection in U937 cells, a human leukemic monocyte lymphoma cell line. The protein expression of tumor necrosis factor α (TNF-α), an inflammatory marker, and myeloid differentiation primary response gene 88 (MyD88), a toll like receptor adaptor molecule, in the infected group increased at 1 and 6 h after M. smegmatis infection of U937 cells. Acetyl coenzyme A acetyl transferase-1 (ACAT-1), peroxisome proliferator-activated receptor-α (PPAR-α), TNF-α, and MyD88 decreased in U937 cells treated with fibrates at 12 and 24 h after treatment. More than a 24 h pretreatment with fibrate resulted in similar expression levels of ACAT-1 and PPAR-α between infected vehicle control and infected groups which were pretreated with fibrate for 24 h. However, upon exposure to M. smegmatis, the cellular expression of the TNF-α and MyD88 in the infected groups pretreated with fibrate for 24 h decreased significantly compared to that in the infected vehicle group. CONCLUSION These results suggest that fibrate pretreatment normalized the levels of inflammatory molecules in Mycobacterium smegmatis-infected U937 cells. Further studies are needed to confirm the findings on pathophysiology and immune defense mechanism of U937 by fibrates during M. tuberculosis infection.
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Affiliation(s)
- Sung-Jo Kim
- Department of Biotechnology, Hoseo University, 165, Baebang, Asan, Chungnam, 336-795, Republic of Korea.
| | - Minho Hong
- Department of Biotechnology, Hoseo University, 165, Baebang, Asan, Chungnam, 336-795, Republic of Korea.
| | - Ki Duk Song
- The Animal Genomics and Breeding Center, Han-Kyong National University, Anseong, 336-795, Republic of Korea.
| | - Hak-Kyo Lee
- The Animal Genomics and Breeding Center, Han-Kyong National University, Anseong, 336-795, Republic of Korea.
| | - Sungweon Ryoo
- Korean Institute of Tuberculosis, Mansu-ri 482, Gangoe-myeon, Chungcheongbuk-do, 363-954, Cheongwon-gun,Republic of Korea.
| | - Tae-Hwe Heo
- Laboratory of Immunology, Integrated Research Institute of Pharmaceutical Sciences, College of Pharmacy, The Catholic University of Korea, Bucheon, 420-743, Republic of Korea. .,NP512, Hall of Cardinal Jin-Suk Cheong, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi-do, 420-743, Republic of Korea.
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Schuessler DL, Parish T. The promoter of Rv0560c is induced by salicylate and structurally-related compounds in Mycobacterium tuberculosis. PLoS One 2012; 7:e34471. [PMID: 22485172 PMCID: PMC3317779 DOI: 10.1371/journal.pone.0034471] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 03/02/2012] [Indexed: 11/18/2022] Open
Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), is a major global health threat. During infection, bacteria are believed to encounter adverse conditions such as iron depletion. Mycobacteria synthesize iron-sequestering mycobactins, which are essential for survival in the host, via the intermediate salicylate. Salicylate is a ubiquitous compound which is known to induce a mild antibiotic resistance phenotype. In M. tuberculosis salicylate highly induces the expression of Rv0560c, a putative methyltransferase. We identified and characterized the promoter and regulatory elements of Rv0560c. PRv0560c activity was highly inducible by salicylate in a dose-dependent manner. The induction kinetics of PRv0560c were slow, taking several days to reach maximal activity, which was sustained over several weeks. Promoter activity could also be induced by compounds structurally related to salicylate, such as aspirin or para-aminosalicylic acid, but not by benzoate, indicating that induction is specific to a structural motif. The −10 and −35 promoter elements were identified and residues involved in regulation of promoter activity were identified in close proximity to an inverted repeat spanning the −35 promoter element. We conclude that Rv0560c expression is controlled by a yet unknown repressor via a highly-inducible promoter.
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Affiliation(s)
| | - Tanya Parish
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
- * E-mail:
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Nematollahi A, Aminimoghadamfarouj N, Wiart C. Reviews on 1,4-naphthoquinones from Diospyros L. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2012; 14:80-88. [PMID: 22263598 DOI: 10.1080/10286020.2011.633515] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The genus Diospyros is one of the most important sources of bioactive compounds, exclusively 1,4-naphthoquinones. The following information is an attempt to cover the developments in the biology and phytochemistry of 1,4-naphthoquinones isolated from this genus, as well as the studies done and the suggested mechanisms regarding their activities. During the past 60 years, many of these agents have been isolated from Diospyros L. Twelve considerable bioactive structures are reported in this review. The basic 1,4-naphthoquinone skeletons, on which a large number of studies have been done, are plumbagin and diospyrin. Today, the potential for development of leads from 1,4-naphthoquinones obtained from Diospyros L. is growing dramatically, mainly in the area of anticancer and antibacterial investigations. The data prepared and described here are intended to be served as a reference tool to the natural products and chemistry specialists in order to expand the rational drug design.
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Affiliation(s)
- Alireza Nematollahi
- Research Center of Natural Products Safety and Medicinal Plants, North Khorasan University of Medical Sciences, Bojnurd, Iran.
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Padhye S, Dandawate P, Yusufi M, Ahmad A, Sarkar FH. Perspectives on medicinal properties of plumbagin and its analogs. Med Res Rev 2010; 32:1131-58. [PMID: 23059762 DOI: 10.1002/med.20235] [Citation(s) in RCA: 205] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Plumbagin is one of the simplest plant secondary metabolite of three major phylogenic families viz. Plumbaginaceae, Droseraceae, and Ebenceae, and exhibits highly potent biological activities, including antioxidant, antiinflammatory, anticancer, antibacterial, and antifungal activities. Recent investigations indicate that these activities arise mainly out of its ability to undergo redox cycling, generating reactive oxygen species and chelating trace metals in biological system. The compound is endowed with a property to inhibit the drug efflux mechanism in drug-resistant bacteria, thereby allowing intracellular accumulation of the potent drug molecules. An interesting bioactivity exhibited by this compound is the elimination of stringent, conjugative, multidrug-resistant plasmids from several bacterial strains including opportunistic bacteria, such as Acinetobacter baumannii. Moreover, plumbagin effectively induces apoptosis and causes cell cycle arrest, which is, in part, due to the inactivation of NF-κB in cancer cells. Therefore, it has been suggested that designing "hybrid drug molecules" of plumbagin by combining it with other appropriate anticancer agents may lead to the generation of novel and potent anticancer drugs with pleiotropic action against human cancers. This comprehensive review is an attempt to understand the chemistry of plumbagin and catalog its biological activities reported to date.
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Affiliation(s)
- Subhash Padhye
- Department of Pathology, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Hudson Webber Cancer Research Center, Detroit, Michigan 48201, USA
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Rodea-Palomares I, Petre AL, Boltes K, Leganés F, Perdigón-Melón JA, Rosal R, Fernández-Piñas F. Application of the combination index (CI)-isobologram equation to study the toxicological interactions of lipid regulators in two aquatic bioluminescent organisms. WATER RESEARCH 2010; 44:427-438. [PMID: 19683324 DOI: 10.1016/j.watres.2009.07.026] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 07/13/2009] [Accepted: 07/18/2009] [Indexed: 05/28/2023]
Abstract
Pharmaceuticals in the aquatic environment do not appear singly and usually occur as complex mixtures, whose combined effect may exhibit toxicity to the aquatic biota. We report an environmental application of the combination index (CI)-isobologram equation, a method widely used in pharmacology to study drug interactions, to determine the nature of toxicological interactions of three fibrates toward two aquatic bioluminescent organisms, Vibrio fischeri and the self-luminescent cyanobacterial recombinant strain Anabaena CPB4337. The combination index-isobologram equation method allows computerized quantitation of synergism, additive effect and antagonism. In the Vibrio test, the fibrate combinations showed antagonism at low effect levels that turned into an additive effect or synergism at higher effect levels; by contrast, in the Anabaena test, the fibrate combinations showed a strong synergism at the lowest effect levels and a very strong antagonism at high effect levels. We also evaluated the nature of the interactions of the three fibrates with a real wastewater sample in the cyanobacterial test. We propose that the combination index-isobologram equation method can serve as a useful tool in ecotoxicological assessment.
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Affiliation(s)
- Ismael Rodea-Palomares
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, 2 Darwin Street, Cantoblanco, 28049 Madrid, Spain
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Janin YL. Antituberculosis drugs: ten years of research. Bioorg Med Chem 2007; 15:2479-513. [PMID: 17291770 DOI: 10.1016/j.bmc.2007.01.030] [Citation(s) in RCA: 360] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Revised: 12/26/2006] [Accepted: 01/17/2007] [Indexed: 02/03/2023]
Abstract
Tuberculosis is today amongst the worldwide health threats. As resistant strains of Mycobacterium tuberculosis have slowly emerged, treatment failure is too often a fact, especially in countries lacking the necessary health care organisation to provide the long and costly treatment adapted to patients. Because of lack of treatment or lack of adapted treatment, at least two million people will die of tuberculosis this year. Due to this concern, this infectious disease was the focus of renewed scientific interest in the last decade. Regimens were optimized and much was learnt on the mechanisms of action of the antituberculosis drugs used. Moreover, the quest for original drugs overcoming some of the problems of current regimens also became the focus of research programmes and many new series of M. tuberculosis growth inhibitors were reported. This review presents the drugs currently used in antituberculosis treatments and the most advanced compounds undergoing clinical trials. We then provide a description of their mechanism of action along with other series of inhibitors known to act on related biochemical targets. This is followed by other inhibitors of M. tuberculosis growth, including recently reported compounds devoid of a reported mechanism of action.
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Affiliation(s)
- Yves L Janin
- URA 2128 CNRS-Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris Cedex 15, France.
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Ahmad Z, Sharma S, Khuller GK. Azole antifungals as novel chemotherapeutic agents against murine tuberculosis. FEMS Microbiol Lett 2006; 261:181-6. [PMID: 16907718 DOI: 10.1111/j.1574-6968.2006.00350.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The present study was designed to evaluate the in vivo antimycobacterial potential of econazole alone and in combination with antitubercular drugs against tuberculosis in mice. Econazole was found to reduce bacterial burden by 90% in the lungs and spleen of mice infected with 1 x 10(7) cells of Mycobacterium tuberculosis and was found to be equipotent to rifampicin. Further, our results indicate that econazole can replace rifampicin/isoniazid as well as both rifampicin and isoniazid in chemotherapy of murine tuberculosis. Econazole alone or in combination with antitubercular drugs did not produce any hepatotoxicity in normal or M. tuberculosis-infected mice.
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Affiliation(s)
- Zahoor Ahmad
- Department of Biochemistry, Postgraduate Institute of Medical Education & Research, Chandigarh, India
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