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1.
Pak J Pharm Sci ; 32(4): 1671-1677, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31608889

RESUMO

The current research aims at development and assessment of o/w nystatin microemulsion. The pseudoternary phase diagrams were developed to determine microemulsion existence regions by water titration method. Nystatin was liquefied in the blend of oil phase, surfactant and cosurfactant. Microemulsion was made by deliberate mixing of water and stirring in this blend. The S-mix (surfactant-cosurfactant mixtures) of the ratio 1:2 was found better than 1:1 and 2:1 S-mix ratios. In vitro permeation studies by Franz diffusion cell revealed faster rate of nystatin release from such microemulsion (5.37µg/cm2/h) as compared to nystrin (4.79µg/cm2/h), a commercially available aqueous suspension. Kinetic modeling demonstrated zero order drug release and release mechanism found to be anomalous i.e. superposition of dispersion and swelling controlled drug release. Antifungal activity was performed using well diffusion method in vitro against Candida albicans cultures grown on Sabouraud's dextrose agar. The results also confirmed the high diffusion rate of drug from microemulsion as compared to aqueous suspension. The outcomes of this study propose that topical microemulsion of nystatin provides better antifungal activity as compared to emulsion gels or aqueous suspensions.


Assuntos
Antifúngicos/farmacologia , Emulsões/química , Emulsões/farmacologia , Nistatina/farmacologia , Administração Tópica , Antifúngicos/administração & dosagem , Antifúngicos/química , Antifúngicos/farmacocinética , Candida albicans/efeitos dos fármacos , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Liberação Controlada de Fármacos , Emulsões/administração & dosagem , Emulsões/farmacocinética , Excipientes/química , Concentração de Íons de Hidrogênio , Nistatina/administração & dosagem , Nistatina/química , Nistatina/farmacocinética , Solubilidade , Tensoativos , Viscosidade
2.
Analyst ; 144(21): 6247-6253, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31552926

RESUMO

Intracellular viscosity abnormalities can lead to diabetes, neurodegenerative diseases and cancer. In this work, we developed a mitochondria-targetable fluorescent probe (EIMV) for discriminating normal and inflammatory models by viscosity changes. It was found that EIMV showed excellent properties, including high photostability, low cytotoxicity, red emission and favorable biocompatibility. In view of these unique features, this probe could successfully identify normal and cancer cells via viscosity changes. Furthermore, the EIMV probe successfully identified zebrafish with different viscosities by the same method. Moreover, EIMV exhibited different fluorescence signals in normal and inflammatory mice due to changes in viscosity. Therefore, the probe provides a new method to study the relationship between diseases and viscosity in the fields of biology and medicine.


Assuntos
Corantes Fluorescentes/química , Indóis/química , Inflamação/diagnóstico , Mitocôndrias/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Fluorescência , Humanos , Inflamação/metabolismo , Ionóforos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/química , Monensin/farmacologia , Neoplasias/diagnóstico , Neoplasias/metabolismo , Nistatina/farmacologia , Células RAW 264.7 , Viscosidade , Peixe-Zebra
3.
DNA Cell Biol ; 38(10): 1048-1055, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31433200

RESUMO

DNA condensed agents can improve the transfection efficiency of the cationic liposome delivery system. However, various condensed agents have distinct transfection efficiency and cellular cytotoxicity. The object of this study was to screen the optimal agents with the high transfection efficiency and low cytotoxicity from four polymer compressive materials, polyethylenimine (PEI), chitosan, poly-l-lysine (PLL), and spermidine. DNA was precompressed with these four agents and then combined to cationic liposomes. Subsequently, the entrapment and transfection efficiency of the obtained complexes were investigated. Finally, the particle sizes, cytotoxicity, and endocytosis fashion of these copolymers (Lipo-PEI, Lipo-chitosan, Lipo-PLL, and Lipo-spermidine) were examined. It was found that these four copolymers had significantly lower cytotoxicity and higher transfection efficiency (45.5%, 42.4%, 36.8%, and 47.4%, respectively) than those in the control groups. The transfection efficiency of Lipo-PEI and Lipo-spermidine copolymers were better than the other two copolymers. In 293T cells, nystatin significantly inhibited the transfection efficiency of Lipo-PEI-DNA and Lipo-spermidine-DNA (51.88% and 46.05%, respectively), which suggest that the endocytosis pathway of Lipo-spermidine and Lipo-PEI copolymers was probably caveolin dependent. Our study indicated that these dual-degradable copolymers especially liposome-spermidine copolymer could be used as the potential biocompatible gene delivery carriers.


Assuntos
Quitosana/química , Lipossomos/química , Polietilenoimina/química , Polilisina/química , Espermidina/química , Transfecção/métodos , Cátions , Caveolina 1/genética , Caveolina 1/metabolismo , Quitosana/metabolismo , Colesterol/química , Colesterol/metabolismo , Endocitose/efeitos dos fármacos , Endocitose/genética , Ácidos Graxos Monoinsaturados/química , Ácidos Graxos Monoinsaturados/metabolismo , Células HEK293 , Humanos , Lipossomos/metabolismo , Nistatina/farmacologia , Tamanho da Partícula , Plasmídeos/química , Plasmídeos/metabolismo , Polietilenoimina/metabolismo , Polilisina/metabolismo , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo , Espermidina/metabolismo
4.
G3 (Bethesda) ; 9(9): 3035-3043, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31352406

RESUMO

Candida orthopsilosis is diploid asexual yeast that causes human disease. Most C. orthopsilosis isolates arose from at least four separate hybridizations between related, but not identical, parents. Here, we used population genomics data to correlate genotypic and phenotypic variation in 28 C. orthopsilosis isolates. We used cosine similarity scores to identify 65 variants with potential high-impact (deleterious effects) that correlated with specific phenotypes. Of these, 19 were Single Nucleotide Polymorphisms (SNPs) that changed stop or start codons, or splice sites. One variant resulted in a premature stop codon in both alleles of the gene ZCF29 in C. orthopsilosis isolate 185, which correlated with sensitivity to nystatin and caffeine. We used CRISPR-Cas9 editing to introduce this polymorphism into two resistant C. orthopsilosis isolates. Introducing the stop codon resulted in sensitivity to caffeine and to ketoconazole, but not to nystatin. Our analysis shows that it is possible to associate genomic variants with phenotype in asexual Candida species, but that only a small amount of genomic variation can be easily explored.


Assuntos
Cafeína/farmacologia , Candida parapsilosis/efeitos dos fármacos , Candida parapsilosis/fisiologia , Proteínas Fúngicas/genética , Animais , Antifúngicos/farmacologia , Sistemas CRISPR-Cas , Candida parapsilosis/genética , Candida parapsilosis/patogenicidade , Códon de Terminação , Genótipo , Cetoconazol/farmacologia , Lepidópteros/microbiologia , Testes de Sensibilidade Microbiana , Microrganismos Geneticamente Modificados , Nistatina/farmacologia , Fenótipo , Polimorfismo de Nucleotídeo Único , Virulência/genética
5.
Int. microbiol ; 22(2): 239-246, jun. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184830

RESUMO

Silver nanoparticles (SN) have been recently developed as a new class of antimicrobial agents against numerous pathogenic microorganisms. SN have also been used as efficient drug delivery systems and have been linked with increasing drug potency. Here, we demonstrated the enhanced antifungal efficacy of nystatin (NYT) and fluconazole (FLU) after conjugation with SN. The antifungal bioactivity of NYT- and FLU-coated SN was evaluated against Candida albicans ATCC 10231 and Aspergillus brasiliensis ATCC 16404 by the agar tube dilution method. The aim of this study was to determine and compare the antifungal efficacy of NYT and FLU with their SN and, finally, the combination of both nanoparticles as NYT-SN + FLU-SN against pathogenic fungi. The results indicated that all test samples showed a dose-dependent response against tested fungi. SN significantly enhanced the antifungal effects of NYT and FLU as compared to drugs alone. We observed a remarkable increase in the percent inhibition of both fungi (90-100%) when treated with a combination of both nanoparticles NYT-SN + FLU-SN at 200 μg/mL only. Furthermore, the morphological modifications occurred at the surface of fungal species were also analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). While tested against primary human cell line, all SN showed negligible cytotoxicity. Hence, these results suggest that the combination of SN with NYT and FLU may have clinical implications in the treatment of fungal infections. However, in vivo studies are needed before recommending the use of these nanoparticles safely in clinical situations


No disponible


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Nanopartículas Metálicas , Prata/farmacologia , Fluconazol/farmacologia , Nistatina/farmacologia , Aspergillus/ultraestrutura , Candida albicans/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Propriedades de Superfície/efeitos dos fármacos
6.
Bull Exp Biol Med ; 166(6): 735-738, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31020586

RESUMO

Comparative analysis of the effects of chemically transformed polyene antibiotics pimaricin, nystatin, lucensomycin, amphotericin B, and levorin on biological objects in vivo and in vitro revealed the greatest biological activity of original amphotericin B and levorin with its derivatives. The study also examined the effects of alkyl derivatives of amphotericin B and levorin modified in certain parts of the lactone ring on the lipid and biological membranes. It is established that methylated levorin possesses larger biological activity than the original antibiotic. Examination of the effects of alkyl derivatives of levorin and amphotericin B on cell cultures C6 (rat glioma) and HeLa (human cervical carcinoma) in vitro revealed the antitumor action of methylated levorin and original amphotericin B.


Assuntos
Anfotericina B/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Candicidina/farmacologia , Alquilação , Anfotericina B/química , Animais , Antibacterianos/química , Antineoplásicos/química , Candicidina/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Lucensomycin/química , Lucensomycin/farmacologia , Natamicina/química , Natamicina/farmacologia , Neuroglia , Nistatina/química , Nistatina/farmacologia , Ratos , Relação Estrutura-Atividade
7.
Braz Oral Res ; 33: e023, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30970088

RESUMO

We evaluated the antifungal and antibiofilm potential of the hydroalcoholic extract of bark from Anadenanthera colubrina (vell.) Brenan, known as Angico, against Candida spp. Antifungal activity was evaluated using the microdilution technique through the Minimum Inhibitory and Fungicide Concentrations (MIC and MFC). The antibiofilm potential was tested in mature biofilms formed by Candida species and analyzed through the counting of CFU/mL and scanning electron micrograph (SEM). In vivo toxicity and therapeutic action was evaluated in the Galleria mellonella model. The treatment with the extract, in low doses, was able to reduce the growth of planktonic cells of Candida species. MIC values range between 19.5 and 39 µg/mL and MFC values range between 79 and 625 µg/mL. In addition was able to reduce the number of CFU/mL in biofilms and to cause structural alteration and cellular destruction, observed via SEM. A. colubrina showed low toxicity in the in vivo assay, having not affected the viability of the larvae at doses below 100mg/kg and high potential in the treatment of C. albicans infection. Considering its high antifungal potential, its low toxicity and potential to treatment of infections in in vivo model, A. colubrina extract is a strong candidate for development of a new agent for the treatment of oral candidiasis.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Fabaceae/química , Extratos Vegetais/farmacologia , Análise de Variância , Contagem de Colônia Microbiana , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Nistatina/farmacologia , Reprodutibilidade dos Testes , Fatores de Tempo
8.
J Appl Microbiol ; 127(1): 68-77, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31013388

RESUMO

AIMS: Candida albicans biofilms are commonly associated with severe oral infections. We previously discovered that a crude extract from the Solidago virgaurea plant (SV extract) was a potent inhibitor of C. albicans biofilm formation. Here, we further investigate the mechanisms underlying C. albicans biofilm inhibition by the SV extract. METHODS AND RESULTS: The SV extract was shown to inhibit laboratory and clinical C. albicans isolates adherence and hyphal transition on inert support and epithelial human cells, without affecting viability and growth of planktonic yeasts. Interestingly, RT-PCR-based experiments demonstrated that some key genes involved in adhesion and hyphal morphological switch (e.g. Hwp1p, Ece1p, Als3p) were strongly down-regulated by the SV extract. Moreover, antimicrobial synergy testing (checkerboard assay) demonstrated that antifungal effects of miconazole, nystatin or a common antiseptic mouthwash were synergistically improved when used in combination with the SV extract. CONCLUSIONS: The SV extract prevents C. albicans biofilm formation through direct inhibition of key adherence and hyphae-associated genes. SIGNIFICANCE AND IMPACT OF THE STUDY: Biofilm is considered as a key virulence factor of C. albicans infection. Our discovery of an inhibitor specifically acting on genes involved in biofilm formation paves the way for the future development of a new class of antifungal product.


Assuntos
Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Extratos Vegetais/farmacologia , Solidago/química , Antifúngicos/farmacologia , Células Cultivadas , Sinergismo Farmacológico , Expressão Gênica/efeitos dos fármacos , Humanos , Hifas/efeitos dos fármacos , Miconazol/farmacologia , Nistatina/farmacologia , Extratos Vegetais/química
9.
Virol J ; 16(1): 37, 2019 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-30909932

RESUMO

BACKGROUND: Porcine sapelovirus (PSV), a species of the genus Sapelovirus within the family Picornaviridae, are a significant cause of enteritis, pneumonia, polioencephalomyelitis and reproductive disorders in pigs. However, the life cycle of PSV on the molecular level is largely unknown. METHODS: Here, we used chemical inhibitors, RNA interference, and overexpression of dominant negative (DN) mutant plasmids to verify the roles of distinct endocytic pathways involved in PSV entry into porcine small intestinal epithelial cell line (IPEC-J2). RESULTS: Our experiments indicated that PSV infection was inhibited when cells were pre-treated with NH4Cl or chloroquine. Inhibitors nystatin, methyl-ß-cyclodextrin, dynasore and wortmannin dramatically reduced PSV entry efficiency, whereas the inhibitors chlorpromazine and EIPA had no effect. Furthermore, overexpression caveolin DN mutant and siRNA against caveolin also decreased virus titers and VP1 protein synthesis, whereas overexpression EPS15 DN mutant and siRNA against EPS15 did not reduce virus infection. CONCLUSIONS: Our findings suggest that PSV entry into IPEC-J2 cells depends on caveolae/lipid raft mediated-endocytosis, that is pH-dependent and requires dynamin and PI3K but is independent of clathrin and macropinocytosis.


Assuntos
Cavéolas/virologia , Endocitose , Células Epiteliais/virologia , Picornaviridae/fisiologia , Internalização do Vírus/efeitos dos fármacos , Cloreto de Amônio/farmacologia , Animais , Linhagem Celular , Cloroquina/farmacologia , Clatrina/metabolismo , Dinaminas/metabolismo , Hidrazonas/farmacologia , Nistatina/farmacologia , Picornaviridae/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno , Suínos
10.
Int Microbiol ; 22(2): 239-246, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30810990

RESUMO

Silver nanoparticles (SN) have been recently developed as a new class of antimicrobial agents against numerous pathogenic microorganisms. SN have also been used as efficient drug delivery systems and have been linked with increasing drug potency. Here, we demonstrated the enhanced antifungal efficacy of nystatin (NYT) and fluconazole (FLU) after conjugation with SN. The antifungal bioactivity of NYT- and FLU-coated SN was evaluated against Candida albicans ATCC 10231 and Aspergillus brasiliensis ATCC 16404 by the agar tube dilution method. The aim of this study was to determine and compare the antifungal efficacy of NYT and FLU with their SN and, finally, the combination of both nanoparticles as NYT-SN + FLU-SN against pathogenic fungi. The results indicated that all test samples showed a dose-dependent response against tested fungi. SN significantly enhanced the antifungal effects of NYT and FLU as compared to drugs alone. We observed a remarkable increase in the percent inhibition of both fungi (90-100%) when treated with a combination of both nanoparticles NYT-SN + FLU-SN at 200 µg/mL only. Furthermore, the morphological modifications occurred at the surface of fungal species were also analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). While tested against primary human cell line, all SN showed negligible cytotoxicity. Hence, these results suggest that the combination of SN with NYT and FLU may have clinical implications in the treatment of fungal infections. However, in vivo studies are needed before recommending the use of these nanoparticles safely in clinical situations.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Fluconazol/farmacologia , Nanopartículas Metálicas , Nistatina/farmacologia , Prata/farmacologia , Aspergillus/ultraestrutura , Candida albicans/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Propriedades de Superfície/efeitos dos fármacos
11.
Pharmazie ; 74(1): 34-38, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30782248

RESUMO

Decontamination of patients' clinical devices in intensive care units is generally performed with an antifungal suspension. Nystatin is a widely-used high spectrum antifungal due to its low systemic absorption. However, nystatin has high hydrophobicity which hinders the contact with the internal lumen of the devices. In this work, hydrophilic micellar systems of nystatin were developed with sodium deoxycholate on silicone endotracheal tubes. The physical characteristics of the micellar system at different nystatin:deoxycholate ratios were studied using scanning electron microscopy, X-ray powder diffraction and differential scanning calorimetry. The electron microscopy results reveal that the deoxycholate micellar system altered the surface morphology, and the size of the aggregates was observed to be smaller. The hydrophilic structures of deoxycholate produce systems with a high surface area containing nystatin molecules on their interior. The X-ray and differential scanning calorimetry assays revealed a typical change in the crystallinity of micellar systems when the deoxycholate proportion increases. The endothermic peak of nystatin was not observed in the micellar systems as a consequence of the reduced crystallinity. Nystatin was homogenously dispersed in the surfactant matrix. Micellar systems with 1:0.8 nystatin:deoxycholate ratio (MS-N:DC [1:0.8]) showed increased antifungal activity compared to nystatin raw material. Micellar systems also achieved an over 40% inhibition of Candida albicans biofilm formation. The results obtained in this study conclude that the higher hydrophilic characteristic of the surfactant deoxycholate enhances nystatin penetration into the surface of the endotracheal tubes.


Assuntos
Antifúngicos/administração & dosagem , Candida albicans/efeitos dos fármacos , Ácido Desoxicólico/química , Nistatina/administração & dosagem , Antifúngicos/química , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Cristalização , Interações Hidrofóbicas e Hidrofílicas , Intubação Intratraqueal/instrumentação , Micelas , Microscopia Eletrônica de Varredura , Nistatina/química , Nistatina/farmacologia , Silicones/química , Tensoativos/química , Difração de Raios X
12.
Analyst ; 144(7): 2387-2392, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30801605

RESUMO

Mitochondria play central roles in plenty of biological processes, such as apoptosis, signaling, and cell differentiation. Mitochondrial depolarization is a significant sign of deterioration of intracellular status. Although many fluorescent probes for visualizing mitochondria have been delivered, two-photon red-emitting mitochondrial probes capable of detecting mitochondrial depolarization remain rare. In this work, by linking a pyrene moiety to a quinoline salt, we have constructed two-photon red-emitting mitochondrial probes, MVQ and HVQ. Between them, HVQ with a longer side chain exhibits higher hydrophobic properties, and can image mitochondria with high-fidelity due to the aggregation caused quenching effect. In cooperation with MTDR, a commercialized mitochondrial probe, HVQ, could be used to image the depolarization of mitochondria induced by a protonophore and hydrogen peroxide. We believe that HVQ can serve as a powerful tool for the investigation of mitochondria and mitochondrial membrane potential in fundamental biological research.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Fótons , Pirenos/química , Corantes Fluorescentes/metabolismo , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Modelos Moleculares , Conformação Molecular , Nistatina/farmacologia , Pirenos/metabolismo , Quinolinas/química
13.
BMC Infect Dis ; 19(1): 54, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30651066

RESUMO

BACKGROUND: Extracellular hydrolases (phospholipase, aspartyl protease and haemolysin) and biofilm production are considered as major virulence factors of the opportunistic pathogenic fungus Candida albicans. However, the impact of antifungal therapy on such virulence attributes is not well investigated. The common antifungal agents may disturb the production of secreted hydrolases as well as biofilm formation. Accordingly, this study addressed the effect of subinhibitory concentrations (sub-MICs) of selected antifungal agents on some virulence factors of C. albicans clinical isolates. METHODS: C. albicans isolates (n = 32) were recovered from different clinical samples and their identification was confirmed to the species level. Antifungal susceptibility profiles of isolates were determined against (nystatin, fluconazole and micafungin) and minimum inhibitory concentrations (MICs) were interpreted according to Clinical and Laboratory Standards Institute guidelines. Virulence determinants comprising secreted hydrolases (phospholipase, aspartyl protease and haemolysin) and biofilm formation were investigated in the presence of the sub-MICs of the tested antifungal agents. RESULTS: Treatment of clinical C. albicans isolates with subinhibitory nystatin, fluconazole and micafungin concentrations significantly decreased production of extracellular hydrolases. Nystatin had the greatest inhibitory effect on phospholipase and aspartyl protease production. However, micafungin showed the highest reducing effect on the hemolytic activity of the treated clinical isolates. Moreover, nystatin and micafungin, but not fluconazole, had a noticeable significant impact on inhibiting biofilm formation of C. albicans clinical isolates. CONCLUSION: Our findings highlighted the significant influences of commonly prescribed antifungal agents on some virulence factors of C. albicans. Accordingly, antifungal therapy may modulate key virulence attributes of C. albicans.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/metabolismo , Hidrolases/metabolismo , Fatores de Virulência/metabolismo , Antifúngicos/administração & dosagem , Ácido Aspártico Proteases/metabolismo , Biofilmes/efeitos dos fármacos , Candida albicans/isolamento & purificação , Candida albicans/patogenicidade , Egito , Fluconazol/farmacologia , Proteínas Fúngicas/metabolismo , Humanos , Micafungina/administração & dosagem , Micafungina/farmacologia , Testes de Sensibilidade Microbiana , Nistatina/administração & dosagem , Nistatina/farmacologia , Fosfolipases/metabolismo
14.
J Microbiol Biotechnol ; 29(1): 171-177, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30415525

RESUMO

Parasitic infections have remained a significant burden on human and animal health. In part, this is due to lack of clinically-approved, novel antimicrobials and a lack of interest by the pharmaceutical industry. An alternative approach is to modify existing clinically-approved drugs for efficient delivery formulations to ensure minimum inhibitory concentration is achieved at the target site. Nanotechnology offers the potential to enhance the therapeutic efficacy of drugs through modification of nanoparticles with ligands. Amphotericin B, nystatin, and fluconazole are clinically available drugs in the treatment of amoebal and fungal infections. These drugs were conjugated with gold nanoparticles. To characterize these gold-conjugated drug, atomic force microscopy, ultraviolet-visible spectrophotometry and Fourier transform infrared spectroscopy were performed. These drugs and their gold nanoconjugates were examined for antimicrobial activity against the protist pathogen, Acanthamoeba castellanii of the T4 genotype. Moreover, host cell cytotoxicity assays were accomplished. Cytotoxicity of these drugs and drug-conjugated gold nanoparticles was also determined by lactate dehydrogenase assay. Gold nanoparticles conjugation resulted in enhanced bioactivity of all three drugs with amphotericin B producing the most significant effects against Acanthamoeba castellanii (p < 0.05). In contrast, bare gold nanoparticles did not exhibit antimicrobial potency. Furthermore, amoebae treated with drugs-conjugated gold nanoparticles showed reduced cytotoxicity against HeLa cells. In this report, we demonstrated the use of nanotechnology to modify existing clinically-approved drugs and enhance their efficacy against pathogenic amoebae. Given the lack of development of novel drugs, this is a viable approach in the treatment of neglected diseases.


Assuntos
Acanthamoeba castellanii/efeitos dos fármacos , Amebicidas/química , Amebicidas/farmacologia , Ouro/química , Nanopartículas Metálicas/química , Acanthamoeba castellanii/crescimento & desenvolvimento , Anfotericina B/química , Anfotericina B/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fluconazol/química , Fluconazol/farmacologia , Células HeLa , Humanos , Nanomedicina , Nistatina/química , Nistatina/farmacologia
15.
Curr Top Med Chem ; 18(27): 2338-2346, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30569856

RESUMO

Leishmaniasis is an infectious disease caused by protozoal parasites belonging to Leishmania genus. Different clinical outcomes can be observed depending on the parasite species and health condition of patients. It can range from single cutaneous lesion until deadly visceral form. The treatment of all forms of leishmaniasis is based on pentavalent antimonials, and in some cases, the second-line drug, amphotericin B is used. Beside the toxicity of both drugs, parasites can be resistant to antimonial in some areas of the world. This makes fundamental the characterization of new drugs with leishmanicidal effect. Thus, the aim of the present work was to study the leishmanicidal activity of drugs able to interfere with ergosterol pathway (fenticonazole, tioconazole, nystatin, rosuvastatin and voriconazole) against promastigote and amastigote forms of L.(L.) amazonensis, L.(V.) braziliensis and L.(L.) infantum, and its impact on morphological and physiological changes in L.(L.) amazonensis or in host macrophages. We observed that fenticonazole, tioconazole and nystatin drugs eliminated promastigote and intracellular amastigotes, being fenticonazole and nystatin the most selective towards amastigote forms. Rosuvastatin and voriconazole did not present activity against amastigote forms of Leishmania sp. In addition, the drugs with leishmanicidal activity interfered with parasite mitochondrion. Although drugs did not stimulate NO and H2O2, specially fenticonazole was able to alkalize infected host macrophages. These results suggest well established and non-toxic antifungal drugs can be repurposed and used in leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Imidazóis/farmacologia , Leishmania/efeitos dos fármacos , Nistatina/farmacologia , Antiprotozoários/química , Imidazóis/química , Nistatina/química , Testes de Sensibilidade Parasitária , Especificidade da Espécie
16.
Viruses ; 10(12)2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30563082

RESUMO

The infection by dengue virus (DENV) of microglia causes cell activation and migration via a mechanism involving viral entry, RNA release, and Toll-like receptor 3 signaling. In this study, we demonstrated that secreted chemotactic factors present in microglial conditioned medium (MCM) facilitated cell motility in the murine BV2 microglial cells. The pharmacological disruption of lipid rafts/caveolae reduced DENV- and ultraviolet (UV)-inactivated MCM-induced microglial cell migration. An antibody-based cytokine/chemokine array showed an increase in macrophage inflammatory protein (MIP)-3ß in MCM produced using DENV-infected cells. The pharmacological inhibition of c-Jun N-terminal kinase (JNK) retarded UV-MCM-induced microglial cell migration. These results demonstrate that secreted MIP-3ß and its effect on the JNK signaling pathways mediates DENV-induced BV2 microglial cell migration.


Assuntos
Movimento Celular , Quimiocina CCL19/imunologia , Vírus da Dengue/imunologia , Microglia/citologia , Transdução de Sinais , Animais , Cavéolas/efeitos dos fármacos , Linhagem Celular , Meios de Cultivo Condicionados , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Microdomínios da Membrana/efeitos dos fármacos , Camundongos , Microglia/virologia , Nistatina/farmacologia , Raios Ultravioleta
17.
Braz Dent J ; 29(4): 359-367, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30462762

RESUMO

The aim of this study was to evaluate the antifungal activity of Terpinen-4-ol associated with nystatin, on single and mixed species biofilms formed by Candida albicans and Candida tropicalis, as well as the effect of terpinen-4-ol on adhesion in oral cells and the enzymatic activity. The minimum inhibitory concentrations and minimum fungicide concentrations of terpinen-4-ol and nystatin on Candida albicans and Candida tropicalis were determined using the microdilution broth method, along with their synergistic activity ("checkerboard" method). Single and mixed species biofilms were prepared using the static microtiter plate model and quantified by colony forming units (CFU/mL). The effect of Terpinen-4-ol in adhesion of Candida albicans and Candida tropicalis in coculture with oral keratinocytes (NOK Si) was evaluated, as well as the enzymatic activity by measuring the size of the precipitation zone, after the growth agar to phospholipase, protease and hemolysin. Terpinen-4-ol (4.53 mg mL-1) and nystatin (0.008 mg mL-1) were able to inhibit biofilms growth, and a synergistic antifungal effect was showed with the drug association, reducing the inhibitory concentration of nystatin up to 8 times in single biofilm of Candida albicans, and 2 times in mixed species biofilm. A small decrease in the adhesion of Candida tropicalis in NOK Si cells was showed after treatment with terpinen-4-ol, and nystatin had a greater effect for both species. For enzymatic activity, the drugs showed no action. The effect potentiated by the combination of terpinen-4-ol and nystatin and the reduction of adhesion provide evidence of its potential as an anti-fungal agent.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Nistatina/farmacologia , Terpenos/farmacologia , Linhagem Celular Transformada , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana
18.
Mol Pharm ; 15(12): 5585-5590, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30351959

RESUMO

Nanosized extracellular vesicles (EVs) possess the natural machinery needed to enter selectively and transmit complex molecular messages efficiently into targeted cells. The intracellular fate of the vesicular cargos depends on the route of internalization. Therefore, understanding the mechanism of attachment and subsequent intake of these vesicles (before and after exerting any modification) is imperative. Here the extent of communication, the uptake kinetics, and the pathways of endothelial EVs into endothelial cells in the presence of specific pharmacological inhibitors were assessed by imaging flow cytometry. The results showed that the uptake of endothelial EVs into endothelial cells was largely an energy-dependent process using predominantly a receptor-mediated, clathrin-dependent pathway.


Assuntos
Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Exossomos/metabolismo , Nanopartículas/metabolismo , Animais , Linhagem Celular , Clorpromazina/farmacologia , Clatrina/metabolismo , Endocitose/efeitos dos fármacos , Células Endoteliais/ultraestrutura , Endotélio Vascular/citologia , Endotélio Vascular/ultraestrutura , Exossomos/ultraestrutura , Citometria de Fluxo/métodos , Macrolídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência/métodos , Nistatina/farmacologia
19.
Sci Rep ; 8(1): 13584, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30206268

RESUMO

Polyene macrolides such as nystatin A1 and amphotericin B belong to a large family of very valuable antifungal polyketide compounds typically produced by soil actinomycetes. Recently, nystatin-like Pseudonocardia polyene (NPP) A1 has been identified as a unique disaccharide-containing tetraene antifungal macrolide produced by Pseudonocardia autotrophica. Despite its significantly increased water solubility and decreased hemolytic activity, its antifungal activity remains limited compared with that of nystatin A1. In this study, we developed NPP B1, a novel NPP A1 derivative harboring a heptaene core structure, by introducing two amino acid substitutions in the putative NADPH-binding motif of the enoyl reductase domain in module 5 of the NPP A1 polyketide synthase NppC. The low level NPP B1 production yield was successfully improved by eliminating the native plasmid encoding a polyketide biosynthetic gene cluster present in P. autotrophica. In vitro and in vivo antifungal activity and toxicity studies indicated that NPP B1 exhibited comparable antifungal activity against Candida albicans and was less toxic than the most potent heptaene antifungal, amphotericin B. Moreover, NPP B1 showed improved pharmacokinetic parameters compared to those of amphotericin B, suggesting that NPP B1 could be a promising candidate for development into a pharmacokinetically improved and less-toxic polyene antifungal antibiotic.


Assuntos
Actinobacteria/genética , Antifúngicos/farmacologia , Candidíase/tratamento farmacológico , Macrolídeos/farmacologia , Engenharia Metabólica/métodos , Polienos/farmacologia , Actinobacteria/química , Actinobacteria/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/metabolismo , Sítios de Ligação , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Candidíase/mortalidade , Dissacarídeos/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Macrolídeos/química , Macrolídeos/isolamento & purificação , Macrolídeos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , NADP/química , NADP/metabolismo , Nistatina/farmacologia , Plasmídeos/química , Plasmídeos/metabolismo , Polienos/química , Polienos/isolamento & purificação , Polienos/metabolismo , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Alinhamento de Sequência , Relação Estrutura-Atividade , Análise de Sobrevida
20.
Arch Oral Biol ; 95: 100-107, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30096698

RESUMO

OBJECTIVE: To evaluate the importance of Candida glabrata, Candida parapsilosis and their close-related species, Candida bracarensis, Candida nivariensis, Candida metapsilosis and Candida orthopsilosis in patients with oral candidiasis and, to determine the in vitro activities of antifungal drugs currently used for the treatment. METHODS: One hundred fourteen isolates of C. glabrata and 97 of C. parapsilosis, previously identified by conventional mycological methods, were analysed by molecular techniques. In vitro antifungal susceptibility to fluconazole, itraconazole, miconazole, and nystatin was evaluated by CLSI M44-A2 disk diffusion test, and by CLSI M27-A3 microdilution for fluconazole. RESULTS: All C. glabrata isolates were identified as C. glabrata sensu stricto, 93 out of 97 C. parapsilosis isolates as C. parapsilosis sensu stricto, three as C. orthopsilosis and one as C. metapsilosis. Candida glabrata was mainly isolated in mixed cultures but C. parapsilosis complex was more frequent in pure culture. Candida metapsilosis and C. orthopsilosis were isolated as pure culture and both species were susceptible to all antifungal agents tested. Most C. glabrata isolates were susceptible to miconazole and nystatin, but resistant to fluconazole and itraconazole. Azole cross resistance was also observed. Candida parapsilosis isolates were susceptible to fluconazole although azole cross resistance to miconazole and itraconazole was observed. CONCLUSION: This study highlights the importance of accurate identification and antifungal susceptibility testing of oral Candida isolates in order to have an in-depth understanding of the role of C. glabrata and C. parapsilosis in oral candidiasis.


Assuntos
Antifúngicos/farmacologia , Candida glabrata/efeitos dos fármacos , Candida parapsilosis/efeitos dos fármacos , Candidíase Bucal/tratamento farmacológico , Candidíase Bucal/microbiologia , Farmacorresistência Fúngica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Candida glabrata/isolamento & purificação , Candida parapsilosis/isolamento & purificação , Feminino , Humanos , Masculino , Miconazol/farmacologia , Pessoa de Meia-Idade , Nistatina/farmacologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência
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