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Bvumbi MV, van der Westhuyzen C, Mmutlane EM, Ngwane A. Riminophenazine Derivatives as Potential Antituberculosis Agents: Synthesis, Biological, and Electrochemical Evaluations. Molecules 2021; 26:molecules26144200. [PMID: 34299475 PMCID: PMC8303532 DOI: 10.3390/molecules26144200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/23/2021] [Accepted: 05/24/2021] [Indexed: 11/16/2022] Open
Abstract
A series of novel riminophenazine derivatives, having ionizable alkyl substituents at N-5 and a variety of substituents on the C-3 imino nitrogen, at C-8 and on the pendant aryl group, have been designed and synthesized. Preliminary investigations into the relationship between lipophilicity, redox potential, and antimycobacterial activity were conducted, using the in vitro activity against Mycobacterium tuberculosis H37Rv, mammalian cytotoxicity, and the redox potential of the compounds determined by cyclic voltammetry as measures. Results revealed an activity “cliff” associated with C-8 substitution (10l and 10m) that, along with defined redox activity, point to a new class of riminophenazines as potential anti-tuberculosis agents having reasonable activity (MIC99 ~1 µM).
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Affiliation(s)
- Mpelegeng Victoria Bvumbi
- Department of Chemistry, University of Johannesburg, Auckland Park 2006, South Africa;
- CSIR, Pharmaceutical Technologies, Pretoria 0001, South Africa;
- Department of Chemistry, University of Venda, Private X5050, Thohoyandou 0950, South Africa
- Correspondence: ; Tel.: +27-15-962-8756
| | | | - Edwin M. Mmutlane
- Department of Chemistry, University of Johannesburg, Auckland Park 2006, South Africa;
| | - Andile Ngwane
- Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg 7505, South Africa;
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Koval A, Bassanini I, Xu J, Tonelli M, Boido V, Sparatore F, Amant F, Annibali D, Leucci E, Sparatore A, Katanaev VL. Optimization of the clofazimine structure leads to a highly water-soluble C3-aminopyridinyl riminophenazine endowed with improved anti-Wnt and anti-cancer activity in vitro and in vivo. Eur J Med Chem 2021; 222:113562. [PMID: 34116325 DOI: 10.1016/j.ejmech.2021.113562] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/10/2021] [Accepted: 05/17/2021] [Indexed: 12/15/2022]
Abstract
Triple-negative breast cancer (TNBC) is a cancer subtype critically dependent upon excessive activation of Wnt pathway. The anti-mycobacterial drug clofazimine is an efficient inhibitor of canonical Wnt signaling in TNBC, reducing tumor cell proliferation in vitro and in animal models. These properties make clofazimine a candidate to become first targeted therapy against TNBC. In this work, we optimized the clofazimine structure to enhance its water solubility and potency as a Wnt inhibitor. After extensive structure-activity relationships investigations, the riminophenazine 5-(4-(chlorophenyl)-3-((2-(piperazin-1-yl)ethyl)imino)-N-(pyridin-3-yl)-3,5-dihydrophenazin-2-amine (MU17) was identified as the new lead compound for the riminophenazine-based targeted therapy against TNBC and Wnt-dependent cancers. Compared to clofazimine, the water-soluble MU17 displayed a 7-fold improved potency against Wnt signaling in TNBC cells resulting in on-target suppression of tumor growth in a patient-derived mouse model of TNBC. Moreover, allowing the administration of reduced yet effective dosages, MU17 displayed no adverse effects, most notably no clofazimine-related skin coloration.
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Affiliation(s)
- Alexey Koval
- Department of Cell Physiology and Metabolism, Translational Research Centre in Oncohaematology, Faculty of Medicine, University of Geneva, 1206, Geneva, Switzerland
| | - Ivan Bassanini
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano, 20133, Milano, Italy; Istituto di Scienze e Tecnologie Chimiche "Giulio Natta", Consiglio Nazonale delle Ricerche, 20131, Milano, Italy
| | - Jiabin Xu
- Department of Cell Physiology and Metabolism, Translational Research Centre in Oncohaematology, Faculty of Medicine, University of Geneva, 1206, Geneva, Switzerland; Department of Biomedical Sciences, Faculty of Biology and Medicine, 1011, University of Lausanne, Lausanne, Switzerland
| | - Michele Tonelli
- Dipartimento di Farmacia, Università di Genova, 16132, Genova, Italy
| | - Vito Boido
- Dipartimento di Farmacia, Università di Genova, 16132, Genova, Italy
| | - Fabio Sparatore
- Dipartimento di Farmacia, Università di Genova, 16132, Genova, Italy
| | - Frederic Amant
- Gynecological Oncology Laboratory, Department of Oncology, KU Leuven and Leuven Cancer Institute (LKI), 3000, Leuven, Belgium; Department of Obstetrics and Gynecology, University Hospitals Leuven and Department of Oncology, 3000, Leuven, Belgium; Centre for Gynecologic Oncology Amsterdam (CGOA), Antoni Van Leeuwenhoek-Netherlands Cancer Institute (AvL-NKI), University Medical Center (UMC), 1066, Amsterdam, the Netherlands
| | - Daniela Annibali
- Gynecological Oncology Laboratory, Department of Oncology, KU Leuven and Leuven Cancer Institute (LKI), 3000, Leuven, Belgium
| | - Eleonora Leucci
- Laboratory for RNA Cancer Biology, Department of Oncology, KU Leuven, 3000, Leuven, Belgium; Trace, LKI Leuven Cancer Institute, KU Leuven, 3000, Leuven, Belgium
| | - Anna Sparatore
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano, 20133, Milano, Italy.
| | - Vladimir L Katanaev
- Department of Cell Physiology and Metabolism, Translational Research Centre in Oncohaematology, Faculty of Medicine, University of Geneva, 1206, Geneva, Switzerland; School of Biomedicine, Far Eastern Federal University, 690922, Vladivostok, Russia.
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Bvumbi MV. Activity of Riminophenazines against Mycobacterium tuberculosis: A Review of Studies that Might be Contenders for Use as Antituberculosis Agents. ChemMedChem 2020; 15:2207-2219. [PMID: 32844566 PMCID: PMC7756396 DOI: 10.1002/cmdc.202000580] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Indexed: 02/01/2023]
Abstract
Tuberculosis is one of the leading cause of death in the world, mainly due to the increasing number of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) strains. Factors such as the HIV pandemic contribute further. Also, the ineffectiveness of the chemotherapy in current use increases the mortality rate. Therefore, new and repurposed antituberculosis drugs are urgently needed for the treatment of MDR-TB, and riminophenazines are among those drugs that are being reinvestigated for their potential in the treatment of TB. This review delivers a brief historical account of riminophenazines, their general synthesis, mechanisms of action, and their physicochemical properties. The discussion is limited to those studies that investigated the activity of these compounds as antituberculosis agents. Given their unique properties, this review will be of great significance in giving direction towards the design and development of new riminophenazine analogues.
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Bassanini I, Parapini S, Basilico N, Sparatore A. Novel Hydrophilic Riminophenazines as Potent Antiprotozoal Agents. ChemMedChem 2019; 14:1940-1949. [PMID: 31658408 DOI: 10.1002/cmdc.201900522] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 10/04/2019] [Indexed: 01/22/2023]
Abstract
SAR studies on a set of novel hydrophilic C-2 aminopyridinyl riminophenazines bearing variously functionalized basic side chains at C-3 were conducted. The novel compounds were evaluated for in vitro activity against two different species of Leishmania promastigotes, intramacrophage Leishmania amastigotes, chloroquine-sensitive and chloroquine-resistant strains of P. falciparum, and also against mature-stage P. falciparum gametocytes. Their cytotoxicity was evaluated as well on BMDM cell lines. Most of the new compounds potently inhibited the growth of both genera of protozoa with IC50 values in the high nanomolar range and good selectivities versus mammalian cells. Besides their potent activity against asexual intraerythrocytic stages of P. falciparum, three compounds showed potential as transmission-blocking agents. The key role of the hydrophilic C-2 aminopyridinyl substituent to improve the leishmanicidal activity and the influence of the length and the nature of the basic side chain on the antiprotozoal activity and cytotoxicity were underlined.
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Affiliation(s)
- Ivan Bassanini
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - Silvia Parapini
- Dipartimento di Scienze Biomediche, Chirurgiche e Odontoiatriche, Università degli Studi di Milano, Via Pascal, 36, 20133, Milan, Italy
| | - Nicoletta Basilico
- Dipartimento di Scienze Biomediche, Chirurgiche e Odontoiatriche, Università degli Studi di Milano, Via Pascal, 36, 20133, Milan, Italy
| | - Anna Sparatore
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
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Wang SL, Dong WB, Dong XL, Zhu WM, Wang FF, Han F, Yan X. Comparison of twelve single-drug regimens for the treatment of type 2 diabetes mellitus. Oncotarget 2017; 8:72700-72713. [PMID: 29069819 PMCID: PMC5641162 DOI: 10.18632/oncotarget.20282] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 07/18/2017] [Indexed: 12/28/2022] Open
Abstract
We performed a network meta-analysis to compare the efficacy of 12 single-drug regimens (Glibenclamide, Glimepiride, Pioglitazone, Rosiglitazone, Repaglinide, Metformin, Sitaglitin, Exenatide, Liraglutide, Acarbose, Benfluorex, and Glipizide) in the treatment of type 2 diabetes mellitus (T2DM). Fifteen relevant randomized controlled trials (RCTs) were included; direct and indirect evidence from these studies was combined, and weighted mean difference (WMD) and surface under the cumulative ranking curves (SUCRAs) were examined to evaluate the monotherapies. Liraglutide was more effective than Glimepiride, Pioglitazone, Sitaglitin, Exenatide, and Glipizide at reducing glycated hemoglobin (HbA1c) levels. In contrast, Acarbose was less effective than Glibenclamide, Glimepiride, Pioglitazone, Rosiglitazone, Repaglinide, Metformin, and Liraglutide at decreasing HbA1c levels. Reductions in fasting plasma glucose (FPG) levels were similar after all treatments. Rosiglitazone was less effective than Glibenclamide and Repaglinide at reducing total cholesterol (TC) levels. High density lipoprotein (HDL), low density lipoprotein (LDL), and triglyceride levels did not differ after treatment with any of the monotherapies. HbA1c and FPG SUCRA values were highest for Liraglutide, while HbA1c and FPG values were lowest for Acarbose, and TC and LDL values were lowest for Rosiglitazone. These results suggest that Liraglutide may be most effective, and Acarbose least effective, at reducing blood glucose levels, while Glibenclamide, Repaglinide, and Metformin may be most effective, and Rosiglitazone least effective, at reducing lipoidemia, in T2DM patients.
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Affiliation(s)
- Shao-Lian Wang
- Department of Endocrinology, Jinan Central Hospital, Jinan 250013, P.R. China
| | - Wen-Bin Dong
- Pharmaceutical Preparation Section, Jinan Central Hospital, Jinan 250013, P.R. China
| | - Xiao-Lin Dong
- Department of Endocrinology, Jinan Central Hospital, Jinan 250013, P.R. China
| | - Wen-Min Zhu
- Department of Endocrinology, Jinan Central Hospital, Jinan 250013, P.R. China
| | - Fang-Fang Wang
- Department of Endocrinology, Jinan Central Hospital, Jinan 250013, P.R. China
| | - Fang Han
- Department of Endocrinology, Jinan Central Hospital, Jinan 250013, P.R. China
| | - Xin Yan
- Department of Endocrinology, Jinan Central Hospital, Jinan 250013, P.R. China
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Cholo MC, Mothiba MT, Fourie B, Anderson R. Mechanisms of action and therapeutic efficacies of the lipophilic antimycobacterial agents clofazimine and bedaquiline. J Antimicrob Chemother 2016; 72:338-353. [PMID: 27798208 DOI: 10.1093/jac/dkw426] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Drug-resistant (DR)-TB is the major challenge confronting the global TB control programme, necessitating treatment with second-line anti-TB drugs, often with limited therapeutic efficacy. This scenario has resulted in the inclusion of Group 5 antibiotics in various therapeutic regimens, two of which promise to impact significantly on the outcome of the therapy of DR-TB. These are the 're-purposed' riminophenazine, clofazimine, and the recently approved diarylquinoline, bedaquiline. Although they differ structurally, both of these lipophilic agents possess cationic amphiphilic properties that enable them to target and inactivate essential ion transporters in the outer membrane of Mycobacterium tuberculosis. In the case of bedaquiline, the primary target is the key respiratory chain enzyme F1/F0-ATPase, whereas clofazimine is less selective, apparently inhibiting several targets, which may underpin the extremely low level of resistance to this agent. This review is focused on similarities and differences between clofazimine and bedaquiline, specifically in respect of molecular mechanisms of antimycobacterial action, targeting of quiescent and metabolically active organisms, therapeutic efficacy in the clinical setting of DR-TB, resistance mechanisms, pharmacodynamics, pharmacokinetics and adverse events.
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Affiliation(s)
- Moloko C Cholo
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa
| | - Maborwa T Mothiba
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa
| | - Bernard Fourie
- Department of Medical Microbiology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa
| | - Ronald Anderson
- Institute for Cellular and Molecular Medicine, Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa
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Yano T, Kassovska-Bratinova S, Teh JS, Winkler J, Sullivan K, Isaacs A, Schechter NM, Rubin H. Reduction of clofazimine by mycobacterial type 2 NADH:quinone oxidoreductase: a pathway for the generation of bactericidal levels of reactive oxygen species. J Biol Chem 2011; 286:10276-87. [PMID: 21193400 PMCID: PMC3060482 DOI: 10.1074/jbc.m110.200501] [Citation(s) in RCA: 230] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/23/2010] [Indexed: 11/06/2022] Open
Abstract
The mechanism of action of clofazimine (CFZ), an antimycobacterial drug with a long history, is not well understood. The present study describes a redox cycling pathway that involves the enzymatic reduction of CFZ by NDH-2, the primary respiratory chain NADH:quinone oxidoreductase of mycobacteria and nonenzymatic oxidation of reduced CFZ by O(2) yielding CFZ and reactive oxygen species (ROS). This pathway was demonstrated using isolated membranes and purified recombinant NDH-2. The reduction and oxidation of CFZ was measured spectrally, and the production of ROS was measured using a coupled assay system with Amplex Red. Supporting the ROS-based killing mechanism, bacteria grown in the presence of antioxidants are more resistant to CFZ. CFZ-mediated increase in NADH oxidation and ROS production were not observed in membranes from three different Gram-negative bacteria but was observed in Staphylococcus aureus and Saccharomyces cerevisiae, which is consistent with the known antimicrobial specificity of CFZ. A more soluble analog of CFZ, KS6, was synthesized and was shown to have the same activities as CFZ. These studies describe a pathway for a continuous and high rate of reactive oxygen species production in Mycobacterium smegmatis treated with CFZ and a CFZ analog as well as evidence that cell death produced by these agents are related to the production of these radical species.
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Affiliation(s)
| | | | | | - Jeffrey Winkler
- Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Kevin Sullivan
- Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Andre Isaacs
- Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | | | - Harvey Rubin
- From the Departments of Medicine
- Biochemistry and Biophysics, and
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De Logu A, Palchykovska LH, Kostina VH, Sanna A, Meleddu R, Chisu L, Alexeeva IV, Shved AD. Novel N-aryl- and N-heteryl phenazine-1-carboxamides as potential agents for the treatment of infections sustained by drug-resistant and multidrug-resistant Mycobacterium tuberculosis. Int J Antimicrob Agents 2009; 33:223-9. [DOI: 10.1016/j.ijantimicag.2008.09.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 07/30/2008] [Accepted: 09/15/2008] [Indexed: 10/21/2022]
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Huygens F, O'Sullivan JF, van Rensburg CEJ. Antimicrobial Activities of Seven Novel Tetramethylpiperidine-Substituted Phenazines against Multiple-Drug-Resistant Gram-Positive Bacteria. Chemotherapy 2005; 51:263-7. [PMID: 16103666 DOI: 10.1159/000087454] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2004] [Accepted: 03/11/2005] [Indexed: 11/19/2022]
Abstract
BACKGROUND A dramatic increase in multiple-drug-resistant (MDR) Gram-positive pathogens has occurred in recent times, leading to increased rates or morbidity and mortality and also associated with high costs for the treatment of these infections. It is clear that there is an urgent need for the development of effective antimicrobial agents. The anti-bacterial activity of seven 2,2,6,6-tetramethylpiperidine (TMP)-substituted phenazines, compared to clofazimine (B663), were tested against 70 clinical isolates of methicillin-resistant Staphylococcus aureus, MDR Streptococcus pneumoniae and resistant Enterococcus sp. METHODS Standard minimum inhibitory concentration agar dilution susceptibility tests were done on all isolates, including ATCC control strains. RESULTS All the TMP-substituted phenazines were more active than clofazimine against all isolates tested. Compound B4125 was the most active by inhibiting all growth of the organisms tested, including vancomycin-resistant Enterococcus faecium. CONCLUSION Clofazimine has been shown to have anti-staphylococcal activity. We demonstrate enhanced anti-bacterial activity of TMP-substituted phenazines against drug-resistant Gram-positive organisms compared to clofazimine.
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Affiliation(s)
- Flavia Huygens
- Department of Pharmacology, Faculty of Health Sciences, University of Pretoria, South Africa.
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Laursen JB, Nielsen J. Phenazine Natural Products: Biosynthesis, Synthetic Analogues, and Biological Activity. Chem Rev 2004; 104:1663-86. [PMID: 15008629 DOI: 10.1021/cr020473j] [Citation(s) in RCA: 407] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jane Buus Laursen
- Department of Chemistry, Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
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Makgatho ME, Anderson R, O'Sullivan JF, Egan TJ, Freese JA, Cornelius N, van Rensburg CE. Tetramethylpiperidine-substituted phenazines as novel anti-plasmodial agents. Drug Dev Res 2000. [DOI: 10.1002/1098-2299(200006)50:2<195::aid-ddr10>3.0.co;2-t] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Van Rensburg CE, Anderson R, O'Sullivan JF. Riminophenazine compounds: pharmacology and anti-neoplastic potential. Crit Rev Oncol Hematol 1997; 25:55-67. [PMID: 9134311 DOI: 10.1016/s1040-8428(96)00229-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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O'Connor R, O'Sullivan JF, O'Kennedy R. Determination of serum and tissue levels of phenazines including clofazimine. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1996; 681:307-15. [PMID: 8811441 DOI: 10.1016/0378-4347(96)00025-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A rapid and sensitive HPLC method is described for the analysis of synthetic phenazines, including clofazimine, from a variety of biological samples. Phenazines were extracted from serum, tissue and fat using a mixture of dichloromethane and sodium hydroxide. The drugs were then quantified on a reversed-phase C18 column using a mobile phase consisting of 594 ml of water, 400 ml of tetrahydrofuran, 6 ml of concentrated acetic acid and 0.471 g of hexanesulfonic acid. In this mobile phase, each phenazine tested had its own retention time. This allowed one phenazine to be used as an internal standard for the analysis of other phenazines. The method was validated for clofazimine [3-(4-chloroanilino)-10-(4-chlorophenyl)-2,10-dihydro-2-(isopro pylimino) phenazine] and B4090 [7-chloro-3-(4-chloranilino)-10-(4-chlorophenyl)-2, 10-dihydro-2-(2,2,6,6-tetramethylpiperid-4-ylimino)phenazine ] (VI) and shown to be accurate and precise across a broad concentration range from 0.01 to 50 micrograms/g (microgram/ml). Extraction was 100% for each agent across this range. This system was used to measure clofazimine and VI levels following their administration to rats. The pharmacokinetic profile of VI was different to that of clofazimine, with high tissue concentrations but lower fat levels.
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Affiliation(s)
- R O'Connor
- School of Biological Sciences, Dublin City University, Ireland
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Abstract
Clofazimine has been in clinical use for almost 40 years, but little is known of its mechanism of action. The primary indication for clofazimine is multibacillary leprosy, but it is useful in several infectious and noninfectious diseases, such as typical myocobacterial infections, rhinoscleroma, pyoderma gangrenosum, necrobiosis lipoidica, severe acne, pustular psoriasis, and discoid lupus erythematosus. Postulated mechanisms of action include intercalation of clofazimine with bacterial DNA and increasing levels of cellular phospholipase A2. Clinical experience, possible mechanisms of action, and side effects of clofazimine are summarized.
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Affiliation(s)
- J L Arbiser
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts
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15
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O'Connor R, O'Sullivan JF, O'Kennedy R. The pharmacology, metabolism, and chemistry of clofazimine. Drug Metab Rev 1995; 27:591-614. [PMID: 8925720 DOI: 10.3109/03602539508994208] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- R O'Connor
- School of Biological Sciences, Dublin City University, Ireland
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16
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Franzblau SG, Biswas AN, Harris EB. Fusidic acid is highly active against extracellular and intracellular Mycobacterium leprae. Antimicrob Agents Chemother 1992; 36:92-4. [PMID: 1590706 PMCID: PMC189233 DOI: 10.1128/aac.36.1.92] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The activity of fusidic acid against Mycobacterium leprae was studied in axenic medium and in bacilli residing within mouse peritoneal macrophages. Activity was assessed by subsequent quantitation of bacillary radiorespirometric activity. Significant inhibition in both systems was observed at 0.156 micrograms/ml, and an approximately 50% reduction in activity occurred after exposure to 1.25 to 2.5 micrograms/ml. The excellent human pharmacokinetics and in vitro activity of fusidic acid against the leprosy bacillus warrant a clinical trial of this drug for leprosy.
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Affiliation(s)
- S G Franzblau
- Laboratory Research Branch, Gillis W. Long Hansen's Disease Center, Carville, Louisiana 70721
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Franzblau SG. In vitro activities of aminoglycosides, lincosamides, and rifamycins against Mycobacterium leprae. Antimicrob Agents Chemother 1991; 35:1232-4. [PMID: 1929269 PMCID: PMC284318 DOI: 10.1128/aac.35.6.1232] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The in vitro activities of a variety of aminoglycosides, lincosamides, and rifamycins against Mycobacterium leprae were evaluated with the BACTEC 460 system. At 20 micrograms/ml, gentamicin, kanamycin, tobramycin, streptomycin, and amikacin were inactive. Lincomycin was active at 20 micrograms/ml, and clindamycin was active at 0.31 micrograms/ml. Rifamycin SV, rifabutin, and rifampin were active at 3.1, 3.1 to 12.5, and 200 ng/ml, respectively. The in vitro assay correlates well with the in vivo response of M. leprae to antimicrobial agents, with the exception of the aminoglycosides.
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Affiliation(s)
- S G Franzblau
- Laboratory Research Branch, Gillis W. Long Hansen's Disease Center, Carville, Louisiana 70721
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19
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Franzblau SG, White KE. Comparative in vitro activities of 20 fluoroquinolones against Mycobacterium leprae. Antimicrob Agents Chemother 1990; 34:229-31. [PMID: 2183714 PMCID: PMC171562 DOI: 10.1128/aac.34.2.229] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The in vitro activities of 20 fluoroquinolones against Mycobacterium leprae were evaluated by using the BACTEC 460 system. M. leprae was incubated in BACTEC 12B medium at 33 degrees C under reduced oxygen for 2 to 3 weeks in the presence of fluoroquinolones at 0.31 to 5 micrograms/ml. Activity was determined by a reduction in 14CO2 evolution compared with that of drug-free controls. Of the commercially available agents, ofloxacin was most active, while enoxacin and norfloxacin were inactive. However, a number of newer fluoroquinolones (AT-4140, OPC-17100, OPC-17066, PD-117596, PD-124816, PD-127391, and WIN-57273), all containing a cyclopropyl group at R-1 and, with the exception of WIN-57273, either a halogen or methyl group at R-8, were more active than ofloxacin in vitro. Further in vivo evaluations of these agents should help determine their potential for use against leprosy.
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Affiliation(s)
- S G Franzblau
- Laboratory Research Branch, Gillis W. Long Hansen's Disease Center, Carville, Louisiana 70721
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Franzblau SG. Drug susceptibility testing of Mycobacterium leprae in the BACTEC 460 system. Antimicrob Agents Chemother 1989; 33:2115-7. [PMID: 2694952 PMCID: PMC172831 DOI: 10.1128/aac.33.12.2115] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The susceptibility of Mycobacterium leprae to clinical and experimental antileprosy agents was assessed in the BACTEC 460 system. Nude-mouse-derived M. leprae (10(7) cells), incubated in BACTEC 12B medium at 33 degrees C under reduced oxygen, maintained a fairly constant growth index (14CO2 evolution) for 2 to 3 weeks. At concentrations ranging from 0.031 to 2.0 micrograms/ml, dapsone, rifampin, clofazimine, ethionamide, ofloxacin, clarithromycin, and minocycline all effected reductions in the growth index within 1 to 2 weeks, the extent of inhibition increasing with the incubation time. An in vivo rifampin-resistant isolate displayed markedly reduced susceptibility to rifampin compared with an in vivo-susceptible strain. This system appears to be highly suitable for in vitro drug susceptibility testing of M. leprae.
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Affiliation(s)
- S G Franzblau
- Pharmacology Research Department, Gillis W. Long Hansen's Disease Center, Carville, Louisiana 70721
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