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1.
BMC Res Notes ; 13(1): 455, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993780

RESUMO

OBJECTIVE: Lyme disease is a tick-borne, multisystemic disease caused by Borrelia burgdorferi. Standard treatments for early Lyme disease include short courses of oral antibiotics but relapses often occur after discontinuation of treatment. Several studies have suggested that ongoing symptoms may be due to a highly antibiotic resistant form of B. burgdorferi called biofilms. Our recent clinical study reported the successful use of an intracellular mycobacterium persister drug used in treating leprosy, diaminodiphenyl sulfone (dapsone), in combination therapy for the treatment of Lyme disease. In this in vitro study, we evaluated the effectiveness of dapsone individually and in combination with cefuroxime and/or other antibiotics with intracellular activity including doxycycline, rifampin, and azithromycin against Borrelia biofilm forms utilizing crystal violet biofilm mass, and dimethyl methylene blue glycosaminoglycan assays combined with Live/Dead fluorescent microscopy analyses. RESULTS: Dapsone, alone or in various combinations with doxycycline, rifampin and azithromycin produced a significant reduction in the mass and protective glycosaminoglycan layer and overall viability of B. burgdorferi biofilm forms. This in vitro study strongly suggests that dapsone combination therapy could represent a novel and effective treatment option against the biofilm form of B. burgdorferi.


Assuntos
Borrelia burgdorferi , Doença de Lyme , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Dapsona/farmacologia , Humanos , Doença de Lyme/tratamento farmacológico
2.
Int J Mol Sci ; 21(17)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824985

RESUMO

The aim of this study is to examine the use of an inflammasome competitor as a preventative agent. Coronaviruses have zoonotic potential due to the adaptability of their S protein to bind receptors of other species, most notably demonstrated by SARS-CoV. The binding of SARS-CoV-2 to TLR (Toll-like receptor) causes the release of pro-IL-1ß, which is cleaved by caspase-1, followed by the formation and activation of the inflammasome, which is a mediator of lung inflammation, fever, and fibrosis. The NLRP3 (NACHT, LRR and PYD domains-containing protein 3) inflammasome is implicated in a variety of human diseases including Alzheimer's disease (AD), prion diseases, type 2 diabetes, and numerous infectious diseases. By examining the use of 4,4'-diaminodiphenyl sulfone (DDS) in the treatment of patients with Hansen's disease, also diagnosed as Alzheimer's disease, this study demonstrates the diverse mechanisms involved in the activation of inflammasomes. TLRs, due to genetic polymorphisms, can alter the immune response to a wide variety of microbial ligands, including viruses. In particular, TLR2Arg677Trp was reported to be exclusively present in Korean patients with lepromatous leprosy (LL). Previously, mutation of the intracellular domain of TLR2 has demonstrated its role in determining the susceptibility to LL, though LL was successfully treated using a combination of DDS with rifampicin and clofazimine. Of the three tested antibiotics, DDS was effective in the molecular regulation of NLRP3 inflammasome activators that are important in mild cognitive impairment (MCI), Parkinson's disease (PD), and AD. The specific targeting of NLRP3 itself or up-/downstream factors of the NLRP3 inflammasome by DDS may be responsible for its observed preventive effects, functioning as a competitor.


Assuntos
Infecções por Coronavirus/tratamento farmacológico , Dapsona/farmacologia , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pneumonia Viral/tratamento farmacológico , Doença de Alzheimer/patologia , COVID-19 , Clofazimina/farmacologia , Disfunção Cognitiva/patologia , Humanos , Interleucina-1beta/metabolismo , Hanseníase/tratamento farmacológico , Hanseníase/genética , Pandemias , Transtornos Parkinsonianos/patologia , Rifampina/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Receptor 2 Toll-Like/genética
3.
J Mol Model ; 26(6): 138, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415338

RESUMO

The theoretical charge density study for the gas phase of anti-leprosy drug Dapsone has been carried out in the light of the theory of atoms in molecules using density functional theory employing B3LYP(6-311G++(d, p) hybrid functional completed with dispersion corrections. The Hirshfeld surface analysis as well as fingerprint plots has been utilized to visualize and quantify the intermolecular contacts present in the molecule. The topological properties such as electron density and its Laplacian, delocalization index have been elucidated to throw light into the chemical bonding and atomic and molecular details. The electron localization function has been used to visualize and deduce information on the lone pair and the subshells of the Cl atom. The electrostatic potential visualizes the positive and negative electrostatic potential regions which are susceptible to nucleophilic and electrophilic attack. On the whole, this study provides an exact mechanism, interaction, and topological and electrostatic properties of the drug through theoretical insights which all will be a platform for our further investigation of the interaction between dapsone and dihydropteroate synthase (DHPS).


Assuntos
Dapsona/química , Di-Hidropteroato Sintase/antagonistas & inibidores , Modelos Moleculares , Proteínas de Bactérias/antagonistas & inibidores , Química Computacional , Dapsona/farmacologia , Ligação de Hidrogênio , Hansenostáticos/química , Hansenostáticos/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium leprae/enzimologia , Eletricidade Estática
4.
Sci Rep ; 10(1): 6839, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32322091

RESUMO

Leprosy continues to be the belligerent public health hazard for the causation of high disability and eventual morbidity cases with stable prevalence rates, even with treatment by the on-going multidrug therapy (MDT). Today, dapsone (DDS) resistance has led to fear of leprosy in more unfortunate people of certain developing countries. Herein, DDS was chemically conjugated with five phytochemicals independently as dapsone-phytochemical conjugates (DPCs) based on azo-coupling reaction. Possible biological activities were verified with computational chemistry and quantum mechanics by molecular dynamics simulation program before chemical synthesis and spectral characterizations viz., proton-HNMR, FTIR, UV and LC-MS. The in vivo antileprosy activity was monitored using the 'mouse-foot-pad propagation method', with WHO recommended concentration 0.01% mg/kg each DPC for 12 weeks, and the host-toxicity testing of the active DPC4 was seen in cultured-human-lymphocytes in vitro. One-log bacilli cells in DDS-resistant infected mice footpads decreased by the DPC4, and no bacilli were found in the DDS-sensitive mice hind pads. Additionally, the in vitro host toxicity study also confirmed that the DCP4 up to 5,000 mg/L level was safety for oral administration, since a minor number of dead cells were found in red color under a fluorescent microscope. Several advanced bioinformatics tools could help locate the potential chemical entity, thereby reducing the time and resources required for in vitro and in vitro tests. DPC4 could be used in place of DDS in MDT, evidenced from in vivo antileprosy activity and in vitro host toxicity study.


Assuntos
Simulação por Computador , Dapsona , Hansenostáticos , Hanseníase/tratamento farmacológico , Mycobacterium leprae/crescimento & desenvolvimento , Compostos Fitoquímicos , Dapsona/síntese química , Dapsona/química , Dapsona/farmacologia , Humanos , Hansenostáticos/síntese química , Hansenostáticos/química , Hansenostáticos/farmacologia , Hanseníase/metabolismo , Hanseníase/patologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
5.
Exp Lung Res ; 46(5): 157-161, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32286085

RESUMO

Multiple pharmacological interventions tested over the last decades have failed to reduce ARDS mortality. This short note recounts past data indicating that (i) neutrophils home along an IL-8 gradient, (ii) in ARDS, massive neutrophil accumulation and degranulation in and along bronchoalveolar spaces contributes to damage and hypoxia, (iii) large increases in IL-8 are one of the chemotaxic signals drawing neutrophils to the ARDS lung, and (iv) old data from dermatology and glioblastoma research showed that the old drug against Hansen's disease, dapsone, inhibits neutrophils' chemotaxis to IL-8. Therefore dapsone might lower neutrophils' contributions to ARDS lung pathology. Dapsone can create methemoglobinemia that although rarely problematic it would be particularly undesirable in ARDS. The common antacid drug cimetidine lowers risk of dapsone related methemoglobinemia and should be given concomitantly.


Assuntos
Anti-Infecciosos/uso terapêutico , Dapsona/uso terapêutico , Neutrófilos/efeitos dos fármacos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Anti-Infecciosos/farmacologia , Cimetidina/uso terapêutico , Dapsona/farmacologia , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Humanos , Metemoglobinemia/induzido quimicamente , Metemoglobinemia/prevenção & controle
6.
Biochem Pharmacol ; 177: 113993, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32339493

RESUMO

Leprosy is a chronic infectious disease caused my Mycobacterium leprae that primarily affects peripheral nervous system and extremities and is prevalent in tropical countries. Treatment for leprosy with multidrug regimens is very effective compared to monotherapy especially in multibacillary cases. The three major antileprosy drugs currently in use are 4, 4'-diaminodiphenyl sulfone (DDS, dapsone), rifampicin, and clofazimine. During multidrug therapy, the potent antibiotic rifampicin induces the metabolism of dapsone, which results in decreased plasma half-life of dapsone and its metabolites. Furthermore, rifampicin induces its own metabolism and decreases its half-life during monotherapy. Rifampicin upregulates several hepatic microsomal drug-metabolizing enzymes, especially cytochrome P450 (CYP) family that in turn induce the metabolism of dapsone. Clofazimine lacks significant induction of any drug-metabolizing enzyme including CYP family and does not interact with dapsone metabolism. Rifampicin does not induce clofazimine metabolism during combination treatment. Administration of dapsone in the acetylated form (acedapsone) can release the drug slowly into circulation up to 75 days and could be useful for the effective treatment of paucibacillary cases along with rifampicin. This review summarizes the major aspects of antileprosy drug metabolism and drug interactions and the role of cytochrome P450 family of drug metabolizing enzymes, especially CYP3A4 during multidrug regimens for the treatment of leprosy.


Assuntos
Acedapsona/sangue , Clofazimina/sangue , Citocromo P-450 CYP3A/metabolismo , Dapsona/sangue , Hansenostáticos/sangue , Hanseníase/tratamento farmacológico , Rifampina/sangue , Acedapsona/farmacocinética , Acedapsona/farmacologia , Disponibilidade Biológica , Biotransformação , Clofazimina/farmacocinética , Clofazimina/farmacologia , Dapsona/farmacocinética , Dapsona/farmacologia , Interações Medicamentosas , Quimioterapia Combinada , Meia-Vida , Humanos , Hansenostáticos/farmacocinética , Hansenostáticos/farmacologia , Hanseníase/sangue , Hanseníase/microbiologia , Hanseníase/patologia , Taxa de Depuração Metabólica , Redes e Vias Metabólicas/fisiologia , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/crescimento & desenvolvimento , Mycobacterium leprae/patogenicidade , Rifampina/farmacocinética , Rifampina/farmacologia
7.
Cancer Chemother Pharmacol ; 85(3): 563-571, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31915967

RESUMO

PURPOSE: It has been supposed that cardiac toxicity of doxorubicin is due to its production of free radicals and inflammatory cytokines. Dapsone, an antibiotic drug which is the principal in a multidrug regimen for the treatment of leprosy, is a sulfone with anti-inflammatory and antioxidant immunosuppressive properties. Therefore, we designed this study to investigate the possible effects of dapsone on doxorubicin-induced cardiotoxicity. METHODS: Male rats were administrated doxorubicin (2.5 mg/kg) and dapsone (1, 3, 10 mg/kg) intraperitoneally six times in 2 weeks. Then electrocardiographic (ECG) parameters (QRS complexes, RR and QT intervals) alternation, papillary muscle contraction and excitation, and histopathological changes were assessed. Also, the heart tissue levels of malondialdehyde (MDA) as oxidant factor and superoxide dismutase (SOD) as antioxidant enzyme, tumor necrosis factor-alpha (TNF-α) and serum level of CK-MB were analyzed. RESULTS: Administration of dapsone with doxorubicin significantly reversed alterations induced by doxorubicin in serum levels of CK-MB, ECG parameters, papillary muscle contractility and excitation. Furthermore, the measurement of MDA, SOD and TNF-α tissue level indicated that dapsone significantly reduced oxidative stress and inflammation. These findings were consistent with histopathological analysis. CONCLUSION: Dapsone exerts cardioprotective effects on doxorubicin-induced cardiotoxicity through its anti-inflammatory and antioxidant mechanism.


Assuntos
Cardiotoxicidade/tratamento farmacológico , Dapsona/farmacologia , Doxorrubicina/efeitos adversos , Coração/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Cardiotoxicidade/metabolismo , Citocinas/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Masculino , Malondialdeído/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
8.
Int J Dermatol ; 59(7): 787-795, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31909480

RESUMO

Dapsone (4,4'-diaminodiphenylsulfone) is the only remaining sulfone used in anthropoid therapeutics and is commercially available as an oral formulation, an inhaled preparation, and a 5% or 7.5% cream. Dapsone has antimicrobial effects stemming from its sulfonamide-like ability to inhibit the synthesis of dihydrofolic acid. It also has anti-inflammatory properties such as inhibiting the production of reactive oxygen species, reducing the effect of eosinophil peroxidase on mast cells and down-regulating neutrophil-mediated inflammatory responses. This allows for its use in the treatment of a wide variety of inflammatory and infectious skin conditions. Currently in dermatology, the US Food and Drug Administration (FDA)-approved indications for dapsone are leprosy, dermatitis herpetiformis, and acne vulgaris. However, it proved itself as an adjunctive therapeutic agent to many other skin disorders. In this review, we discuss existing evidence on the mechanisms of action of dapsone, its FDA-approved indications, off-label uses, and side effects.


Assuntos
Anti-Infecciosos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Dapsona/uso terapêutico , Uso Off-Label , Dermatopatias/tratamento farmacológico , Acne Vulgar/tratamento farmacológico , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Dapsona/farmacologia , Dermatite Herpetiforme/tratamento farmacológico , Interações Medicamentosas , Humanos , Hanseníase/tratamento farmacológico
9.
J Mater Chem B ; 7(42): 6539-6555, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31584603

RESUMO

To unveil the effect of electrolyte concentration, pH and polymer addition on Tween 80 stabilized nanostructured lipid carriers (NLCs, based on dialkyldimethylammonium bromides DxDAB and Na oleate), an in-depth scattering analysis was performed. Dynamic and static light scattering (DLS/SLS) and small-angle neutron scattering (SANS) techniques along with zeta potential studies were exploited to understand the structural evolution and physical stability of NLCs. In these experiments, we varied the salt concentration, pH, and the admixture of Pluronic F127 in order to elucidate their effect on NLC morphologies. In most cases, two populations of different sizes are present which differ by one order of magnitude. The antileprosy drugs (ALD) Rifampicin and Dapsone were encapsulated in NLCs and the vector properties were assessed for a series of DxDAB (where x = 12, 14, 16 and 18) NLCs. The influence of composition on the entrapment and release behavior of NLCs was investigated: The size of NLCs correlates with the release rate of the incorporated drug. The interaction of drug-loaded NLCs with bovine serum albumin was studied to understand the release of ALD in the plasma.


Assuntos
Dapsona/farmacologia , Portadores de Fármacos/química , Hansenostáticos/farmacologia , Nanopartículas/química , Compostos de Amônio Quaternário/química , Rifampina/farmacologia , Animais , Bovinos , Portadores de Fármacos/metabolismo , Liberação Controlada de Fármacos , Cinética , Nanopartículas/metabolismo , Poloxâmero/química , Poloxâmero/metabolismo , Ligação Proteica , Compostos de Amônio Quaternário/metabolismo , Soroalbumina Bovina/metabolismo
10.
Int J Mycobacteriol ; 8(3): 229-236, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31512598

RESUMO

Background: Leprosy is a neglected tropical disease affecting millions of people. The current treatment against leprosy includes various antibacterial drugs of which dapsone is known to bind to dihydropteroate synthase of Mycobacterium leprae. Dapsone is an expensive antibacterial drug with many side effects. A natural alternative for dapsone having less to no side effects and cheaper in production is needed. The three-dimensional protein structure of dihydropteroate synthase of M. leprae is not available. Methods: Protein homology modeling of target protein was carried out, and protein structure validation and energy minimization were performed. Phytochemicals mentioned in literature having anti-leprosy properties were studied for absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties and that which passed ADMET filters were further carried for comparative in silico docking analysis along with dapsone. Preliminary docking analysis was carried using AutoDock Vina, and results obtained were validated using AutoDock 4.2.6 and SwissDock. Results: Neobavaisoflavone was predicted to be ten times safer for administration than dapsone. On performing in silico docking, it was found that neobavaisoflavone has better binding affinity than dapsone and forms a stable protein-ligand complex. Residues GLY.50, THR.88, and VAL.107 play an important role as binding site residues. Conclusion: Further, in vitro and in vivo experimental studies are required to confirm anti-leprosy properties of neobavaisoflavone over drug dapsone.


Assuntos
Dapsona/farmacologia , Di-Hidropteroato Sintase/antagonistas & inibidores , Isoflavonas/farmacologia , Hansenostáticos/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium leprae/efeitos dos fármacos , Proteínas de Bactérias/antagonistas & inibidores , Sítios de Ligação , Mycobacterium leprae/enzimologia , Compostos Fitoquímicos/farmacologia , Ligação Proteica
11.
Brain Res ; 1708: 181-187, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30571982

RESUMO

Status epilepticus (SE) is a serious medical condition, as it may trigger epileptogenesis. SE produces continuous generalized seizures resulting in irreversible brain damage. Therefore, the use of neuroprotective agents to prevent cell damage, may reduce the impact of SE. The use of diazepam (DZP), has shown limited neuroprotective effect in SE patients. According to previous reports, dapsone (DDS) is able to reduce both cell damage and seizures, when administered 30 min before the onset of seizures. This study is aimed to evaluate the ability of DDS, alone or in combination with DZP starting their administration once the SE is onset to evaluate the control of seizures in rats. Results showed a reduced convulsive electrical activity after 30 min, 1 and 2 h after SE induced by kainic acid (KA) administration, in the animals treated with DZP alone or in combination with DDS. At 24 h, we observed electrical activity similar to baseline in all groups receiving treatment. The animals treated with DDS and DZP alone or in combination showed an increase in the number of viable pyramidal cells but only the combination showed a lower number of damaged pyramidal neurons of hippocampal CA3. In conclusion, DDS plus DZP was able to control SE and to prevent SE-induced damage, when administered in combination with DZP. As DDS is already in use for patients with leprosy, that combination may be a safe, good option for human cases of SE.


Assuntos
Dapsona/farmacologia , Estado Epiléptico/tratamento farmacológico , Animais , Anticonvulsivantes/farmacologia , Diazepam/farmacologia , Eletroencefalografia , Hipocampo/efeitos dos fármacos , Ácido Caínico/efeitos adversos , Masculino , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Células Piramidais/efeitos dos fármacos , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Estado Epiléptico/induzido quimicamente
12.
J Vet Sci ; 19(6): 744-749, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30304888

RESUMO

Dapsone, an antibiotic, has been used to cure leprosy. It has been reported that dapsone has anti-inflammatory activity in hosts; however, the anti-inflammatory mechanism of dapsone has not been fully elucidated. The present study investigated the anti-inflammatory effects of dapsone on bone marrow cells (BMs), especially upon exposure to lipopolysaccharide (LPS). We treated BMs with LPS and dapsone, and the treated cells underwent cellular activity assay, flow cytometry analysis, cytokine production assessment, and reactive oxygen species assay. LPS distinctly activated BMs with several characteristics including high cellular activity, granulocyte changes, and tumor necrosis factor alpha (TNF-α) production increases. Interestingly, dapsone modulated the inflammatory cells, including granulocytes in LPS-treated BMs, by inducing cell death. While the percentage of Gr-1 positive cells was 57% in control cells, LPS increased that to 75%, and LPS plus dapsone decreased it to 64%. Furthermore, dapsone decreased the mitochondrial membrane potential of LPS-treated BMs. At a low concentration (25 µg/mL), dapsone significantly decreased the production of TNF-α in LPS-treated BMs by 54%. This study confirmed that dapsone has anti-inflammatory effects on LPS-mediated inflammation via modulation of the number and function of inflammatory cells, providing new and useful information for clinicians and researchers.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Dapsona/farmacologia , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Células da Medula Óssea/metabolismo , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Granulócitos/efeitos dos fármacos , Granulócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo
13.
J Cell Biochem ; 119(12): 9838-9852, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30125973

RESUMO

Leprosy (causative, Mycobacterium leprae) continues to be the persisting public health problem with stable incidence rates, owing to the emergence of dapsone resistance that being the principal drug in the ongoing multidrug therapy. Hence, to overcome the drug resistance, structural modification through medicinal chemistry was used to design newer dapsone derivative(s) (DDs), against folic acid biosynthesis pathway. The approach included theoretical modeling, molecular docking, and molecular dynamic (MD) simulation as well as binding free energy estimation for validation of newly designed seven DDs, before synthesis. Theoretical modeling, docking, and MD simulation studies were used to understand the mode of binding and efficacy of DDs against the wild-type and mutant dihydropteroate synthases (DHPS). Principal component analysis was performed to understand the conformational dynamics of DHPS-DD complexes. Furthermore, the overall stability and negative-binding free energy of DHPS-DD complexes were deciphered using Molecular Mechanics/Poisson-Boltzmann Surface Area technique. Molecular mechanics study revealed that DD3 possesses higher binding free energy than dapsone against mutant DHPS. Energetic contribution analysis portrayed that van der Waals and electrostatic energy contributes profoundly to the overall negative free energy, whereas polar solvation energy opposes the binding. Finally, DD3 was synthesized and characterized using Fourier-transform infrared spectroscopy, UV, liquid chromatography-mass spectrometry, and proton nuclear magnetic resonance techniques. This study suggested that DD3 could be further promoted as newer antileprosy agent. The principles of medicinal chemistry and bioinformatics tools help to locate effective therapeutics to minimize resources and time in current drug development modules.


Assuntos
Dapsona/farmacologia , Di-Hidropteroato Sintase/antagonistas & inibidores , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mycobacterium leprae/enzimologia , Dapsona/análogos & derivados , Dapsona/metabolismo , Dapsona/uso terapêutico , Di-Hidropteroato Sintase/genética , Di-Hidropteroato Sintase/metabolismo , Quimioterapia Combinada , Hansenostáticos/farmacologia , Hansenostáticos/uso terapêutico , Mutação , Mycobacterium leprae/efeitos dos fármacos , Ligação Proteica , Conformação Proteica
14.
Biomed Pharmacother ; 103: 1392-1396, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29864923

RESUMO

The aim of this work was to assess the feasibility of drug nanosystems combination for oral therapy of multibacillary leprosy. The anti-leprotic drugs dapsone (DAP) and clofazimine (CLZ) were incorporated within polymeric nanosystems and studied per se and in combination. DAP was loaded in Eudragit L100 nanoparticles (NPs-DAP) while CLZ was loaded in (poly(lactic-co-glycolic acid) (NPs-CLZ). The nanosystems exhibited around 200 nm in size and a drug loading of 12% for each drug. In vitro cytotoxicity on intestinal Caco-2 cells revealed that after 8 h incubation, DAP alone and within NPs were not toxic up to 100 µg mL-1, while CLZ per se was toxic, reducing cell viability to 30% at 50 µg mL-1. Caco-2 exposed to the combination of NPs-DAP (100 µg mL-1) and NPs-CLZ (50 µg mL-1) exhibited 80% of viability. Caco-2 monolayer permeability assays revealed that DAP and CLZ in the nanosystems per se or in NPs-DAP/ NPs-CLZ combination crossed the intestinal barrier. No significant differences were observed between the single nanosystems or in combination with the apparent permeability values and the amount of permeated drug. Thus, the NPs-DAP/NPs-CLZ combination seems to be a promising platform to deliver both drugs in association, representing an important step towards the improvement of multibacillary leprosy therapy.


Assuntos
Clofazimina/farmacologia , Dapsona/farmacologia , Sistemas de Liberação de Medicamentos , Intestinos/fisiologia , Nanopartículas/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Impedância Elétrica , Humanos , Intestinos/efeitos dos fármacos
15.
Nanomedicine (Lond) ; 12(16): 1975-1990, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28745104

RESUMO

AIM: To optimize the production of pH-sensitive dapsone (DAP) nanoparticles based on Eugradit L100 (NPs-EL100-DAP) for oral delivery. MATERIALS & METHODS: NPs-EL100-DAP were optimized using a Plackett-Burman design and a Box-Behnken design. The physicochemical properties of the obtained nanoparticles were monitored by microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, differential scanning calorimetry, in vitro release assays, and examined for cytotoxicity and permeation across intestinal barrier. RESULTS: The in vitro release assay of NPs-EL100-DAP confirmed the nanoparticles' pH sensitivity and the ability to deliver DAP at intestinal environment. NPs-EL100-DAP demonstrated enhanced intestinal interactions in comparison to free DAP, across Caco-2 monolayers. CONCLUSION: These studies demonstrate the potential of NPs-EL100-DAP as a therapeutic platform for oral treatment of leprosy.


Assuntos
Dapsona/administração & dosagem , Portadores de Fármacos/química , Hansenostáticos/administração & dosagem , Nanopartículas/química , Administração Oral , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dapsona/farmacologia , Dapsona/toxicidade , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Hansenostáticos/farmacologia , Hansenostáticos/toxicidade , Tamanho da Partícula , Permeabilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Propriedades de Superfície
16.
PLoS Negl Trop Dis ; 11(6): e0005506, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28570560

RESUMO

BACKGROUND: Real-Time PCR-High Resolution Melting (qPCR-HRM) analysis has been recently described for rapid drug susceptibility testing (DST) of Mycobacterium leprae. The purpose of the current study was to further evaluate the validity, reliability, and accuracy of this assay for M. leprae DST in clinical specimens. METHODOLOGY/PRINCIPAL FINDINGS: The specificity and sensitivity for determining the presence and susceptibility of M. leprae to dapsone based on the folP1 drug resistance determining region (DRDR), rifampin (rpoB DRDR) and ofloxacin (gyrA DRDR) was evaluated using 211 clinical specimens from leprosy patients, including 156 multibacillary (MB) and 55 paucibacillary (PB) cases. When comparing the results of qPCR-HRM DST and PCR/direct DNA sequencing, 100% concordance was obtained. The effects of in-house phenol/chloroform extraction versus column-based DNA purification protocols, and that of storage and fixation protocols of specimens for qPCR-HRM DST, were also evaluated. qPCR-HRM results for all DRDR gene assays (folP1, rpoB, and gyrA) were obtained from both MB (154/156; 98.7%) and PB (35/55; 63.3%) patients. All PCR negative specimens were from patients with low numbers of bacilli enumerated by an M. leprae-specific qPCR. We observed that frozen and formalin-fixed paraffin embedded (FFPE) tissues or archival Fite's stained slides were suitable for HRM analysis. Among 20 mycobacterial and other skin bacterial species tested, only M. lepromatosis, highly related to M. leprae, generated amplicons in the qPCR-HRM DST assay for folP1 and rpoB DRDR targets. Both DNA purification protocols tested were efficient in recovering DNA suitable for HRM analysis. However, 3% of clinical specimens purified using the phenol/chloroform DNA purification protocol gave false drug resistant data. DNA obtained from freshly frozen (n = 172), formalin-fixed paraffin embedded (FFPE) tissues (n = 36) or archival Fite's stained slides (n = 3) were suitable for qPCR-HRM DST analysis. The HRM-based assay was also able to identify mixed infections of susceptible and resistant M. leprae. However, to avoid false positives we recommend that clinical specimens be tested for the presence of the M. leprae using the qPCR-RLEP assay prior to being tested in the qPCR-HRM DST and that all specimens demonstrating drug resistant profiles in this assay be subjected to DNA sequencing. CONCLUSION/SIGNIFICANCE: Taken together these results further demonstrate the utility of qPCR-HRM DST as an inexpensive screening tool for large-scale drug resistance surveillance in leprosy.


Assuntos
Farmacorresistência Bacteriana/genética , Hanseníase/tratamento farmacológico , Testes de Sensibilidade Microbiana/métodos , Mycobacterium leprae/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Dapsona/farmacologia , Humanos , Hansenostáticos/farmacologia , Hanseníase/microbiologia , Mycobacterium leprae/isolamento & purificação , Ofloxacino/farmacologia , Reprodutibilidade dos Testes , Rifampina/farmacologia , Sensibilidade e Especificidade , Análise de Sequência de DNA , Pele/microbiologia , Pele/patologia
17.
s.l; s.n; 2017. 18 p. tab, graf.
Não convencional em Inglês | SES-SP, HANSEN, SESSP-ILSLPROD, SES-SP, SESSP-ILSLACERVO, SES-SP | ID: biblio-1053286

RESUMO

BACKGROUND: Real-Time PCR-High Resolution Melting (qPCR-HRM) analysis has been recently described for rapid drug susceptibility testing (DST) of Mycobacterium leprae. The purpose of the current study was to further evaluate the validity, reliability, and accuracy of this assay for M. leprae DST in clinical specimens. METHODOLOGY/PRINCIPAL FINDINGS: The specificity and sensitivity for determining the presence and susceptibility of M. leprae to dapsone based on the folP1 drug resistance determining region (DRDR), rifampin (rpoB DRDR) and ofloxacin (gyrA DRDR) was evaluated using 211 clinical specimens from leprosy patients, including 156 multibacillary (MB) and 55 paucibacillary (PB) cases. When comparing the results of qPCR-HRM DST and PCR/direct DNA sequencing, 100% concordance was obtained. The effects of in-house phenol/chloroform extraction versus column-based DNA purification protocols, and that of storage and fixation protocols of specimens for qPCR-HRM DST, were also evaluated. qPCR-HRM results for all DRDR gene assays (folP1, rpoB, and gyrA) were obtained from both MB (154/156; 98.7%) and PB (35/55; 63.3%) patients. All PCR negative specimens were from patients with low numbers of bacilli enumerated by an M. leprae-specific qPCR. We observed that frozen and formalin-fixed paraffin embedded (FFPE) tissues or archival Fite's stained slides were suitable for HRM analysis. Among 20 mycobacterial and other skin bacterial species tested, only M. lepromatosis, highly related to M. leprae, generated amplicons in the qPCR-HRM DST assay for folP1 and rpoB DRDR targets. Both DNA purification protocols tested were efficient in recovering DNA suitable for HRM analysis. However, 3% of clinical specimens purified using the phenol/chloroform DNA purification protocol gave false drug resistant data. DNA obtained from freshly frozen (n = 172), formalin-fixed paraffin embedded (FFPE) tissues (n = 36) or archival Fite's stained slides (n = 3) were suitable for qPCR-HRM DST analysis. The HRM-based assay was also able to identify mixed infections of susceptible and resistant M. leprae. However, to avoid false positives we recommend that clinical specimens be tested for the presence of the M. leprae using the qPCR-RLEP assay prior to being tested in the qPCR-HRM DST and that all specimens demonstrating drug resistant profiles in this assay be subjected to DNA sequencing. CONCLUSION/SIGNIFICANCE: Taken together these results further demonstrate the utility of qPCR-HRM DST as an inexpensive screening tool for large-scale drug resistance surveillance in leprosy.


Assuntos
Humanos , Rifampina/farmacologia , Pele/microbiologia , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Ofloxacino/farmacologia , Testes de Sensibilidade Microbiana/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise de Sequência de DNA , Farmacorresistência Bacteriana/genética , Dapsona/farmacologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Hansenostáticos/farmacologia , Hanseníase/microbiologia , Hanseníase/tratamento farmacológico , Mycobacterium leprae/isolamento & purificação , Mycobacterium leprae/efeitos dos fármacos
18.
PLoS Negl Trop Dis ; 10(10): e0005041, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27706165

RESUMO

An active search for Mycobacterium leprae drug resistance was carried out, 243 multibacillary patients from endemic regions of Colombia were included from 2004 to 2013 in a surveillance program. This program was a World Health Organization initiative for drug resistance surveillance in leprosy, where Colombia is a sentinel country. M. leprae DNA from slit skin smear and/or skin biopsy samples was amplified and sequenced to identify mutations in the drug resistance determining region (DRDR) in rpoB, folP1, gyrA, and gyrB, the genes responsible for rifampicin, dapsone and ofloxacin drug-resistance, respectively. Three isolates exhibited mutations in the DRDR rpoB gene (Asp441Tyr, Ser456Leu, Ser458Met), two in the DRDR folP1 gene (Thr53Ala, Pro55Leu), and one isolate exhibited mutations in both DRDR rpoB (Ser456Met) and DRDR folP1 (Pro55Leu), suggesting multidrug resistance. One isolate had a double mutation in folP1 (Thr53Ala and Thr88Pro). Also, we detected mutations outside of DRDR that required in vivo evaluation of their association or not with drug resistance: rpoB Arg505Trp, folP1 Asp91His, Arg94Trp, and Thr88Pro, and gyrA Ala107Leu. Seventy percent of M. leprae mutations were related to drug resistance and were isolated from relapsed patients; the likelihood of relapse was significantly associated with the presence of confirmed resistance mutations (OR range 20.1-88.7, p < 0.05). Five of these relapsed patients received dapsone monotherapy as a primary treatment. In summary, the current study calls attention to M. leprae resistance in Colombia, especially the significant association between confirmed resistance mutations and relapse in leprosy patients. A high frequency of DRDR mutations for rifampicin was seen in a region where dapsone monotherapy was used extensively.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Hansenostáticos/farmacologia , Hanseníase/microbiologia , Mycobacterium leprae/efeitos dos fármacos , Vigilância de Evento Sentinela , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Colômbia/epidemiologia , DNA Bacteriano/genética , Dapsona/farmacologia , Dapsona/uso terapêutico , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Hanseníase/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Mycobacterium leprae/genética , Mycobacterium leprae/isolamento & purificação , Ofloxacino/farmacologia , Ofloxacino/uso terapêutico , Reação em Cadeia da Polimerase , Recidiva , Rifampina/farmacologia , Rifampina/uso terapêutico , Pele/microbiologia , Adulto Jovem
19.
Clin Infect Dis ; 63(11): 1482-1484, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27558568

RESUMO

Molecular drug susceptibility testing was performed on skin biopsies from 24 leprosy patients from Guinea-Conakry for the first time. We identified primary drug resistance in 4 cases and a dapsone-resistant cluster caused by the same strain. Primary transmission of drug-resistant Mycobacterium leprae, including a rifampicin-resistant strain, is reported.


Assuntos
Antibióticos Antituberculose/farmacologia , Antituberculosos/farmacologia , Resistência Microbiana a Medicamentos , Hanseníase/microbiologia , Hanseníase/transmissão , Mycobacterium leprae/efeitos dos fármacos , Antibióticos Antituberculose/uso terapêutico , Antituberculosos/uso terapêutico , Biópsia , DNA Bacteriano/genética , Dapsona/farmacologia , Dapsona/uso terapêutico , Feminino , Genoma Bacteriano , Guiné/epidemiologia , Humanos , Hanseníase/epidemiologia , Masculino , Mycobacterium leprae/genética , Mycobacterium leprae/isolamento & purificação , Rifampina/farmacologia , Rifampina/uso terapêutico , Análise de Sequência de DNA , Pele/microbiologia , Pele/patologia
20.
Mol Biosyst ; 12(7): 2178-88, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27120972

RESUMO

Dapsone resistance is a serious impediment to the implementation of the present leprosy control strategies. In the recent past, many studies have been undertaken to address the antibiotic activity and binding pattern of dapsone against both native and mutant (Pro55Leu) folP1. Yet, there is no well-developed structural basis for understanding drug action and there is dire need for new antibacterial therapies. In the present study, molecular simulation techniques were employed alongside experimental strategies to address and overcome the mechanism of dapsone resistance. In essence, we report the identification of small molecule compounds to effectively and specifically inhibit the growth of M. leprae through targeting dihydropteroate synthase, encoded by folP1 which is involved in folic acid synthesis. Initially, ADME and toxicity studies were employed to screen the lead compounds, using dapsone as standard drug. Subsequently, molecular docking was employed to understand the binding efficiency of dapsone and its lead compounds against folP1. Further, the activity of the screened lead molecule was studied by means of molecular dynamics simulation techniques. Furthermore, we synthesized 4-(2-fluorophenylsulfonyl)benzenamine, using (2-fluorophenyl)boronic acid and 4-aminobenzenesulfonyl chloride, and the compound structure was confirmed by (1)H NMR and (13)C NMR spectroscopic techniques. Most importantly, the antibacterial activity of the compound was also examined and compared against dapsone. Overall, the result from our analysis suggested that CID21480113 (4-(2-fluorophenylsulfonyl)benzenamine) could be developed into a promising lead compound and could be effective in treating dapsone resistant leprosy cases.


Assuntos
Dapsona/farmacologia , Di-Hidropteroato Sintase/genética , Descoberta de Drogas , Farmacorresistência Bacteriana , Hansenostáticos/farmacologia , Hanseníase/microbiologia , Mutação , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/genética , Sequência de Aminoácidos , Sítios de Ligação , Dapsona/química , Di-Hidropteroato Sintase/química , Humanos , Hansenostáticos/química , Hanseníase/tratamento farmacológico , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Conformação Proteica
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