Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.126
Filtrar
1.
Arch Microbiol ; 206(3): 133, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430254

RESUMO

In recent years, the study of essential oils as antifungal alternatives and their encapsulation to increase their properties for greater effects has been tested. In this work, nanoparticles of chitosan-Schinus molle L. essential oil (CS-PEO-Np) with a size of 260 ± 31.1 nm were obtained by ionic gelation and evaluated in some growth phases of Aspergillus flavus, a toxigenic fungus. At a concentration of 250 µg/mL of CS-PEO-Np, the A. flavus mycelial growth was inhibited at 97.1% with respect to control, at 96 h of incubation; the germination and viability of spores were inhibited at 74.8 and 40%, respectively, after exposure to 500 µg/mL of these nanomaterials, at 12 h of incubation. The fluorescence images of stained spores with DAPI showed the affectations caused by nanoparticles in the cell membrane, vacuoles and vacuolar content, cell wall, and nucleic acids. For both nanoparticles, CS-Np and CS-PEO-Np, no mutagenic effect was observed in Salmonella Typhimurium; also, the phytotoxic assay showed low-to-moderate toxicity toward seeds, which was dependent on the nanoparticle's concentration. The acute toxicity of CS-PEO-Np to A. salina nauplii was considered low in comparison to CS-Np (control), which indicates that the incorporation of Schinus molle essential oil into nanoparticles of chitosan is a strategy to reduce the toxicity commonly associated with nanostructured materials. The nanoparticulated systems of CS-PEO-Np represent an effective and non-toxic alternative for the control of toxigenic fungi such as A. flavus by delaying the initial growth stage.


Assuntos
Quitosana , Nanopartículas , Óleos Voláteis , Óleos Voláteis/farmacologia , Aspergillus flavus , Quitosana/farmacologia , Schinus , Antifúngicos/toxicidade , Antifúngicos/metabolismo
2.
J Appl Toxicol ; 44(5): 747-755, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38198744

RESUMO

The emergence of resistant fungal species and the toxicity of currently available antifungal drugs are relevant issues that require special consideration. Cyclodextrins inclusion complexes could optimize the antimicrobial activity of such drugs and create a controlled release system with few side effects. This study aimed to assess the in vitro toxicity and antifungal effectiveness of nystatin (Nys) and chlorhexidine (Chx) complexed or not with ß-cyclodextrin (ßCD). First, a drug toxicity screening was performed through the Artemia salina bioassay. Then, the minimum inhibitory concentrations (MICs) against Candida albicans were determined with the broth microdilution test. After MICs determination, the cytotoxicity of the drugs was evaluated through the methyl-thiazolyl-tetrazolium (MTT) and neutral red (NR) assays and through cell morphology analysis. The PROBIT analysis was used to determine the median lethal concentration (LC50), and the cell viability values were submitted to one-way analysis of variance(ANOVA)/Tukey (α = 0.05). Overall, the ßCD-complexed antifungals were less toxic against A. salina than their raw forms, suggesting that inclusion complexes can reduce the toxicity of drugs. The MICs obtained were as follows: Nys 0.5 mg/L; Nys:ßCD 4 mg/L; Chx 4 mg/L; and Chx:ßCD 8 mg/L. Chx showed significant cytotoxicity (MTT: 12.9 ± 9.6%; NR: 10.6 ± 12.5%) and promoted important morphological changes. Cells exposed to the other drugs showed viability above 70% with no cellular damage. These results suggest that antifungals complexed with ßCD might be a biocompatible option for the treatment of Candida-related infections.


Assuntos
Antifúngicos , beta-Ciclodextrinas , Antifúngicos/toxicidade , Candida , Nistatina/toxicidade , Candida albicans , Clorexidina/farmacologia , beta-Ciclodextrinas/toxicidade
3.
Drug Chem Toxicol ; 47(2): 191-202, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36803623

RESUMO

Aspergillus niger causes infections such as otitis and pulmonary aspergillosis in immunocompromised individuals. Treatment involves voriconazole or amphotericin B, and due to the increase in fungal resistance, the search for new compounds with antifungal activity has intensified. In the development of new drugs, cytotoxicity and genotoxicity assays are important, as they allow predicting possible damage that a molecule can cause, and in silico studies predict the pharmacokinetic properties. The aim of this study was to verify the antifungal activity and the mechanism of action of the synthetic amide 2-chloro-N-phenylacetamide against Aspergillus niger strains and toxicity. 2-Chloro-N-phenylacetamide showed antifungal activity against different strains of Aspergillus niger with minimum inhibitory concentrations between 32 and 256 µg/mL and minimum fungicides between 64 and 1024 µg/mL. The minimum inhibitory concentration of 2-chloro-N-phenylacetamide also inhibited conidia germination. When associated with amphotericin B or voriconazole, 2-chloro-N-phenylacetamide had antagonistic effects. Interaction with ergosterol in the plasma membrane is the probable mechanism of action.2-Chloro-N-phenylacetamide has favorable physicochemical parameters, good oral bioavailability and absorption in the gastrointestinal tract, crosses the blood-brain barrier and inhibits CYP1A2. At concentrations of 50 to 500 µg/mL, it has little hemolytic effect and a protective effect for type A and O red blood cells, and in the cells of the oral mucosa it promotes little genotoxic change. It is concluded that 2-chloro-N-phenylacetamide has promising antifungal potential, favorable pharmacokinetic profile for oral administration and low cytotoxic and genotoxic potential, being a promising candidate for in vivo toxicity studies.


Assuntos
Antifúngicos , Aspergilose , Aspergillus , Humanos , Antifúngicos/toxicidade , Anfotericina B/toxicidade , Voriconazol/toxicidade , Voriconazol/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Acetanilidas/uso terapêutico , Testes de Sensibilidade Microbiana
4.
Nature ; 623(7989): 1079-1085, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938782

RESUMO

Decades of previous efforts to develop renal-sparing polyene antifungals were misguided by the classic membrane permeabilization model1. Recently, the clinically vital but also highly renal-toxic small-molecule natural product amphotericin B was instead found to kill fungi primarily by forming extramembraneous sponge-like aggregates that extract ergosterol from lipid bilayers2-6. Here we show that rapid and selective extraction of fungal ergosterol can yield potent and renal-sparing polyene antifungals. Cholesterol extraction was found to drive the toxicity of amphotericin B to human renal cells. Our examination of high-resolution structures of amphotericin B sponges in sterol-free and sterol-bound states guided us to a promising structural derivative that does not bind cholesterol and is thus renal sparing. This derivative was also less potent because it extracts ergosterol more slowly. Selective acceleration of ergosterol extraction with a second structural modification yielded a new polyene, AM-2-19, that is renal sparing in mice and primary human renal cells, potent against hundreds of pathogenic fungal strains, resistance evasive following serial passage in vitro and highly efficacious in animal models of invasive fungal infections. Thus, rational tuning of the dynamics of interactions between small molecules may lead to better treatments for fungal infections that still kill millions of people annually7,8 and potentially other resistance-evasive antimicrobials, including those that have recently been shown to operate through supramolecular structures that target specific lipids9.


Assuntos
Antifúngicos , Rim , Polienos , Esteróis , Animais , Humanos , Camundongos , Anfotericina B/análogos & derivados , Anfotericina B/química , Anfotericina B/toxicidade , Antifúngicos/química , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Células Cultivadas , Colesterol/química , Colesterol/metabolismo , Farmacorresistência Fúngica , Ergosterol/química , Ergosterol/metabolismo , Rim/efeitos dos fármacos , Cinética , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico , Micoses/microbiologia , Polienos/química , Polienos/metabolismo , Polienos/farmacologia , Inoculações Seriadas , Esteróis/química , Esteróis/metabolismo , Fatores de Tempo
5.
Future Microbiol ; 18: 939-947, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37702001

RESUMO

Aim: An IsCT analogue peptide (PepM3) was designed based on structural studies of wasp mastoparans and tested against Candida albicans. Its effects on fungal cell membranes and toxicity were evaluated. Materials & methods: Antifungal activity was analyzed using a microdilution susceptibility test. Toxicity was assessed using human skin keratinocytes (HaCaT) and zebrafish embryos. Results: PepM3 demonstrated activity against C. albicans and a synergistic effect with amphotericin B. The peptide presented fungicidal action with damage to the fungal cell membrane, low toxicity in HaCat cells and was nonteratogenic in zebrafish embryos. Conclusion: Evaluating structural modifications is essential for the development of new agents with potential activity against fungal pathogens and for the reduction of toxic and teratogenic effects.


Assuntos
Candida albicans , Peixe-Zebra , Animais , Humanos , Antifúngicos/toxicidade , Antifúngicos/química , Anfotericina B/farmacologia , Peptídeos/toxicidade , Testes de Sensibilidade Microbiana
6.
Artigo em Inglês | MEDLINE | ID: mdl-37491113

RESUMO

Many fungal genera such as Aspergillus, Penicillium, Fusarium and Alternaria are able to produce, among many other metabolites, the aflatoxins, a group of toxic and carcinogenic compounds. To reduce their formation, synthetic fungicides are used as an effective way of intervention. However, the extensive use of such molecules generates long-term residues into the food and the environment. The need of new antifungal molecules, with high specificity and low off-target toxicity is worth. The aim of this study was to evaluate: i) the toxicity and genotoxicity of newly synthesized molecules with a good anti-mycotoxic activity, and ii) the suitability of the Allium cepa multi-endpoint assay as an early screening method for chemicals. Eight compounds were tested for toxicity by using the A. cepa bulb root elongation test and for genotoxicity using the A. cepa bulb mitotic index, micronuclei and chromosome aberrations tests. Three molecules showed no toxicity, while two induced mild toxic effects in roots exposed to the highest dose (100 µM). A more pronounced toxic effect was caused by the other three compounds for which the EC50 was approximately 50 µM. Furthermore, all molecules showed a clear genotoxic activity, both in terms of chromosomal aberrations and micronuclei. Albeit the known good antifungal activity, the different molecules caused strong toxic and genotoxic effects. The results indicate the suitability of experiments with A. cepa as a research model for the evaluation of the toxic and genotoxic activities of new molecules in plants before they are released into the environment.


Assuntos
Allium , Cebolas , Antifúngicos/toxicidade , Raízes de Plantas , Índice Mitótico , Aberrações Cromossômicas , Dano ao DNA
7.
Microbiol Spectr ; 11(3): e0084423, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37166300

RESUMO

The biological activity of polycations is usually associated with their biocidal properties. Their antibacterial features are well known, but in this work, observations on the antifungal properties of macromolecules obtained by methacrylamido propyl trimethyl ammonium chloride (MAPTAC) polymerization are presented. The results, not previously reported, make it possible to correlate antifungal properties directly with the structure of the macromolecule, in particular the molecular mass. The polymers described here have antifungal activity against some filamentous fungi. The strongest effect occurs for polymers with a mass of about 0.5 mDa which have confirmed activity against the multidrug-resistant species Scopulariopsis brevicaulis, Fusarium oxysporum, and Fusarium solani, as well as the dermatophytes Trichophyton mentagrophytes, Trichophyton rubrum, Trichophyton interdigitale, and Trichophyton tonsurans. In addition, this publication describes the effects of these macromolecular systems on serum and blood components and provides a preliminary assessment of toxicity on cell lines of skin-forming cells, i.e., fibroblasts and keratinocytes. Additionally, using a Franz diffusion chamber, a negligibly low transport of the active polymer through the skin was demonstrated, which is a desirable effect for externally applied antifungal drugs. IMPORTANCE Infectious diseases are a very big medical, social, and economic problem. Even before the COVID-19 pandemic, certain infections were among of the most common causes of death. The difficulties in the treatment of infectious diseases concern in particular fungal diseases, against which we have only a few classes of drugs represented by a few substances. The publication presents the preliminary results of the in vitro antifungal activity studies of four MAPTAC polymers on different fungal species and their cytotoxicity to human cells (fibroblasts and keratinocytes). The paper also compares these properties with analogous ones of two commonly used antifungal drugs, ciclopirox and terbinafine.


Assuntos
Antifúngicos , COVID-19 , Humanos , Antifúngicos/toxicidade , Cloreto de Amônio , Pandemias , Testes de Sensibilidade Microbiana , Polímeros/farmacologia
8.
Microb Biotechnol ; 16(7): 1438-1455, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37191200

RESUMO

Fungi and antifungal compounds are relevant to the United Nation's Sustainable Development Goals. However, the modes-of-action of antifungals-whether they are naturally occurring substances or anthropogenic fungicides-are often unknown or are misallocated in terms of their mechanistic category. Here, we consider the most effective approaches to identifying whether antifungal substances are cellular stressors, toxins/toxicants (that are target-site-specific), or have a hybrid mode-of-action as toxin-stressors (that induce cellular stress yet are target-site-specific). This newly described 'toxin-stressor' category includes some photosensitisers that target the cell membrane and, once activated by light or ultraviolet radiation, cause oxidative damage. We provide a glossary of terms and a diagrammatic representation of diverse types of stressors, toxic substances, and toxin-stressors, a classification that is pertinent to inhibitory substances not only for fungi but for all types of cellular life. A decision-tree approach can also be used to help differentiate toxic substances from cellular stressors (Curr Opin Biotechnol 2015 33: 228-259). For compounds that target specific sites in the cell, we evaluate the relative merits of using metabolite analyses, chemical genetics, chemoproteomics, transcriptomics, and the target-based drug-discovery approach (based on that used in pharmaceutical research), focusing on both ascomycete models and the less-studied basidiomycete fungi. Chemical genetic methods to elucidate modes-of-action currently have limited application for fungi where molecular tools are not yet available; we discuss ways to circumvent this bottleneck. We also discuss ecologically commonplace scenarios in which multiple substances act to limit the functionality of the fungal cell and a number of as-yet-unresolved questions about the modes-of-action of antifungal compounds pertaining to the Sustainable Development Goals.


Assuntos
Antifúngicos , Raios Ultravioleta , Antifúngicos/toxicidade , Antifúngicos/metabolismo , Estresse Oxidativo , Fungos/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-36724546

RESUMO

The antimicrobial activity and biological efficiency of silver nanoparticles (AgNps) have been widely described and can be modeled through stabilizing and reducing agents, especially if they exhibit biocidal properties, which can enhance bioactivity against pathogens. The selective action of AgNps remains a major concern. In this regard, the use of plant extracts for the green synthesis of nanoparticles offers advantages because it improves the toxicity of Nps for microorganisms and is harmless to normal cells. However, biological evaluations of the activity of AgNps synthesized using different reducing agents are determined independently, and comparisons are frequently overlooked. Thus, we investigated and compared the antifungal and cytotoxic effects of two ecological AgNps synthesized from Moringa oleifera aqueous leaf extract (AgNp-M) and glucose (AgNp-G) against azole-resistant clinical isolates of Candida spp. and nontumor mammalian cells. Synthesized AgNps exhibited an antifungal effect on planktonic cells of drug-resistant C. albicans and C. tropicalis (MIC 0.21-52.6 µg/mL). The toxicity was influenced by size. However, the use of M. oleifera extracts allows us to obtain AgNps that are highly selective and nongenotoxic to Vero cells due to modifications of the shape and surface. Therefore, these results suggest that AgNp-M has antimicrobial potential and deserves further investigation for biomedical applications.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Animais , Chlorocebus aethiops , Antifúngicos/toxicidade , Candida , Antibacterianos/farmacologia , Prata/toxicidade , Azóis/toxicidade , Nanopartículas Metálicas/toxicidade , Substâncias Redutoras , Células Vero , Extratos Vegetais/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Mamíferos
10.
Curr Drug Discov Technol ; 20(4): e220223213880, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36809970

RESUMO

BACKGROUND: One of the most important principles in disease control is the health of livestock and poultry feed. Given the natural growth of Th. eriocalyx in Lorestan province, its essential oil can be added to the livestock and poultry feed and prevent the growth of the dominant filamentous fungi. OBJECTIVE: Therefore, this study aimed to identify the dominant moldy fungal agents of livestock and poultry feed, examine phytochemical compounds and analyze antifungal effects, anti-oxidant properties, as well as cytotoxicity against human white blood cells in Th. eriocalyx. METHODS: Sixty samples were collected in 2016. The PCR test was used to amplify ITS1 and ASP1 regions. The analysis of essential oil was conducted by gas chromatography and gas chromatographymass spectrometry devices. MIC and MFC were performed using the broth micro-dilution method. For the analysis of DDPH activity, DDPH was used. Cytotoxicity effect on healthy human lymphocytes was carried out by the MTT method. RESULTS: In this study, A. niger, F. verticilloides and F. circinatum, P. oxalicum, and P. chrysogenum were the most resistant species, and A. oryzae and A. fumigatus, F. prolifratum and F. eqiseti, P. janthnellum were the most susceptible ones. IC50 value of T. daenensis Celak was 41.33 µg/ml, and 100 µl/ml of the essential oil caused slight cell lysis. CONCLUSION: Considering our results, compared with drugs and chemical additives, essential oils can be added to livestock and poultry feed to prevent the growth of filamentous fungi in the livestock and poultry feed.


Assuntos
Óleos Voláteis , Animais , Humanos , Óleos Voláteis/química , Antifúngicos/toxicidade , Antifúngicos/química , Óleos de Plantas/química , Gado , Aves Domésticas , Fungos , Testes de Sensibilidade Microbiana
11.
J Ethnopharmacol ; 301: 115170, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35358625

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Monsonia angustifolia is traditionally used to treat anthrax, heartburn, diarrhea, eye infections and hemorrhoids. Dodonaea angustifolia is frequently used as a treatment for dental pain, microbial infections and jungle fever. The two plant species were selected due to the presence of secondary metabolites such as coumarins, flavonoids, terpenoids, saponins and polyphenolics from the crude extracts, which exhibit pharmacological significance. The pure isolated compounds from the crude extracts are known for their diverse structures and interesting pharmacophores. AIM: To isolate and identify antibacterial and antifungal chemical constituents from Monsonia angustifolia and Dodonaea angustifolia plant extracts and evaluate the cytotoxicity of pure compounds from the crude extracts. MATERIALS AND METHODS: Extractives from M. angustifolia and D. angustifolia plants were isolated using chromatographic techniques and structures were elucidated based on NMR, IR and MS spectroscopic techniques. A microplate serial dilution method was used to evaluate the antibacterial activity of extracts and pure compounds against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and antifungal activity against Candida albicans and Cryptococcus neoformans. The cytotoxicity was determined using the 3-(4, 5-dimethylthiazol)-2, 5-diphenyl tetrazolium bromide (MTT) assay. RESULTS: The dichloromethane, ethyl acetate and methanol crude extracts from the plants exhibited significant inhibition of microbial growth. The phytochemical investigation of these active crude extracts led to the isolation of five pure active compounds, 5-methoxyjusticidin A (1), cis-phytyl diterpenoidal fatty acid ester (2), stigmasterol (3), ß-sitosterol (4) and 5-hydroxy-7,4'-dimethoxyflavone (5). Stigmasterol (3) showed good antifungal activity against Cryptococcus neoformans with a minimum inhibition concentration (MIC) of 25 µg/mL and Candida albicans (MIC = 50 µg/mL). CONCLUSION: Compounds (1-5) isolated from Monsonia angustifolia and Dodonaea angustifolia showed antibacterial and antifungal activities and were non-toxic against Madin-Darby canine kidney (MDCK) cells and VERO monkey kidney (VERO) cells.


Assuntos
Geraniaceae , Sapindaceae , Antifúngicos/toxicidade , Antifúngicos/química , Estigmasterol , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Extratos Vegetais/química , Antibacterianos/toxicidade , Antibacterianos/química
12.
J Pharm Sci ; 112(4): 1081-1088, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36528112

RESUMO

Teicoplanin (Teico) is an antimicrobial agent that spontaneously forms micelles in aqueous media. In this work, we characterized the physicochemical properties of nanoparticles formed by the interaction of Teico with Amphotericin B (AmB). Teico-AmB micelles structure spontaneously in aqueous media, with a particle size of 70-100 nm and a zeta potential of -28 mV. Although the characterization of these nanostructures yielded satisfactory results, in vitro cytotoxicity tests showed high toxicity. Based on this, adding cholesterol to the formulation was evaluated to try to reduce the toxicity of the drug. These Teico-AmB-Chol nanostructures have a larger size, close to 160 nm, but a lower polydispersity index. They also showed strongly negative surface charge and were more stable than Teico-AmB, remaining stable for at least 20 days at 4 °C and 25 °C and against centrifugation, dilution, freezing, lyophilization and re-suspension processes with a recovery percentage of AmB greater than 95%, maintaining their initial size and zeta potential. These Teico-AmB-Chol micelles show lower cytotoxic effect and higher biological activity than Teico-AmB, even than Amfostat® and Ambisome® formulations. These two new nanoparticles, with and without Chol, are discussed as potential formulations able to improve the antifungal therapeutic efficiency of AmB.


Assuntos
Anfotericina B , Nanopartículas , Anfotericina B/toxicidade , Anfotericina B/química , Micelas , Teicoplanina , Antifúngicos/toxicidade , Antifúngicos/química , Nanopartículas/química
13.
Arch Toxicol ; 97(2): 619-629, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36385218

RESUMO

The prenatal exposure to ethanol (Eth), fluconazole (FLUCO) and sodium valproate (VPA) is related to effects on development, producing characteristic syndromic pictures. Among embryotoxic effects described for the three molecules, the alteration on craniofacial morphogenesis is a common feature in humans and animal models, including rodent embryos developed in vitro. The aim of the present work is to evaluate the developmental effects of low Eth serum concentration (17 mM, corresponding to the legal limit to drive in UK, USA, Canada, and many other countries) in mixture with increasing realistic concentrations of the antifungal drug FLUCO (62.5-500 µM) or with increasing realistic concentrations of the antiepileptic drug VPA (31.25-250 µM). Groups exposed to Eth alone (17-127.5 mM), FLUCO alone (62.5-500 µM) or VPA alone (31.25-750 µM) were also included. The chosen alternative animal model was the post-implantation rat whole embryo culture (WEC). E9.5 embryos were exposed in vitro to the test molecules during the whole test period (48 h, corresponding to the developmental stages characteristics of any vertebrate, for human embryos post-fertilization days 23-31). Data were statistically analyzed and processed for modelling applying the benchmark dose (BMD) and relative potency factor (RPF) approaches. Concentration-related effects on facial outcomes were observed in all experimental groups, with a significant enhancement in the groups co-exposed with Eth in comparison to the single exposures. Data obtained by the present work suggest an additional alert for the assumption of even low levels of alcohol in pregnant women during FLUCO or VPA therapy.


Assuntos
Antifúngicos , Fluconazol , Ratos , Feminino , Gravidez , Humanos , Animais , Antifúngicos/toxicidade , Fluconazol/toxicidade , Ácido Valproico/toxicidade , Anticonvulsivantes/toxicidade , Etanol/toxicidade , Consumo de Bebidas Alcoólicas
14.
Int J Pharm ; 628: 122273, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36228881

RESUMO

Pharmaceutical toxicity evaluations often use in vitro systems involving primary cells, cell lines or red blood cells (RBCs). Cell-based analyses ('bioassays') can be cumbersome and typically rely on hard-to-standardize biological materials. Amphotericin B (AmB) toxicity evaluations are primarily based on potassium release from RBCs and share these limitations. This study evaluates the potential substitution of two physicochemical AmB toxicity approaches for the bioassay: Ultraviolet-visible spectroscopy (UV-vis) and in vitro drug release kinetics. UV-vis spectral analyses indicated that liposomal AmB's (L-AmB) main peak position (λmax) and peak ratio (OD346/OD322) are potential toxicity surrogates. Similarly, two first-order release parameters derived from USP-4 in vitro drug release analyses also provided linear relationships with toxicity. These were the initial, overall drug release rate and the ratio of loose to tight AmB pools. Positive slopes and high correlation coefficients (R2 > 0.9) characterized all interrelations between physicochemical parameters and toxicity. These tests converted the manufacturing variables' nonlinear (i.e., curvilinear) relationships with in vitro toxicity to linear responses. Three different toxicity attenuation approaches (2 manufacturing, 1 formulation), covering formulation composition and process aspects, support this approach's universality. These data suggest that one or more spectral and kinetic physicochemical tests can be surrogates for L-AmB in vitro toxicity testing.


Assuntos
Anfotericina B , Antifúngicos , Anfotericina B/toxicidade , Anfotericina B/química , Antifúngicos/toxicidade , Antifúngicos/química , Lipossomos , Liberação Controlada de Fármacos
15.
J Med Chem ; 65(13): 8897-8913, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35786969

RESUMO

Amphotericin B (AMB, 1) is the most powerful antibiotic in treating potentially life-threatening invasive fungal infections (IFIs), though severe toxicity derived from self-aggregation greatly limits its clinical application. Herein, we applied a bisamidation strategy at the C16-COOH and C3'-NH2 to improve the therapeutic properties by suppressing self-aggregation. It was found that basic amino groups at the residue of C16 amide were beneficial to activity, while lipophilic fragments contributed to toxicity reduction. Additionally, N-methyl-amino acetyl and amino acetyl moieties at C3' amide could help keep the fungistatic effectiveness. The modification work culminated in the discovery of 36 (ED50 = 0.21 mg/kg), which exerted a 1.5-fold stronger antifungal efficacy than amphamide, the optimal derivative theretofore, in mice, low self-aggregation propensity, and thus low acute toxicity. With the improvement in therapeutic index and good PK profile, 36 is promising for further development as a second-generation polyene antifungal agent.


Assuntos
Anfotericina B , Antifúngicos , Amidas/toxicidade , Anfotericina B/uso terapêutico , Anfotericina B/toxicidade , Animais , Antifúngicos/toxicidade , Camundongos , Relação Estrutura-Atividade
16.
J Ethnopharmacol ; 297: 115534, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-35842178

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Byrsonima fagifolia Niedenzu (Malpighiaceae) and other Byrsonima species are popularly employed in Brazilian traditional medicine in the form of preparations as cicatrizing, anti-inflammatory, and antimicrobial. AIM OF THE STUDY: To characterize the phytochemical profile of the hydromethanolic extract obtained from B. fagifolia leaves (BF extract) and to evaluate the toxicity and the antifungal activity. MATERIALS AND METHODS: The compounds from BF extract were isolated by HPLC and the structures were elucidated based on extensive analyses of 1D and 2D NMR spectra (HMQC, HMBC and COSY) data. The antifungal effect was determined by the broth microdilution method and the toxicity was evaluated on erythrocytes from sheep's blood and Galleria mellonella larvae. RESULTS: Phytochemical investigation of the BF extract led to the isolation and characterization of pyrogallol, n-butyl gallate, 3,4-di-O-galloylquinic acid, 3,5-di-O-galloylquinic acid, 3,4,5-tri-O-galloylquinic acid, and 1,3,4,5-tetra-O-galloylquinic acid. The BF extract showed high content of galloylquinic acid derivatives reaching more than twenty-times the quercetin derivatives content, according to the quantification by HPLC. These galloylquinic acid derivatives, obtained during this study, and quercetin derivatives, previously isolated, were submitted to the antifungal assays. The BF extract inhibited yeast growth mainly against Cryptococcus spp., at concentrations of 1-16 µg/mL, comparable to isolated compounds galloylquinic acid derivatives. However, the quercetin derivatives as well as quinic acid, gallic acid, and methyl gallate showed lower antifungal effect compared with galloylquinic derivatives. In addition, the BF extract had no hemolytic effect and no toxicity on G. mellonella. CONCLUSION: The phytochemical analysis revealed that galloylquinic acid derivatives are the major compounds in the leaves of B. fagifolia and they are associated to anti-cryptococcal activity and presented reduced toxicity.


Assuntos
Antifúngicos , Malpighiaceae , Animais , Antifúngicos/toxicidade , Malpighiaceae/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Folhas de Planta , Quercetina , Ovinos
17.
Mar Drugs ; 20(3)2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35323514

RESUMO

The world is already facing the devastating effects of the SARS-CoV-2 pandemic. A disseminated mucormycosis epidemic emerged to worsen this situation, causing havoc, especially in India. This research aimed to perform a multitargeted docking study of marine-sponge-origin bioactive compounds against mucormycosis. Information on proven drug targets and marine sponge compounds was obtained via a literature search. A total of seven different targets were selected. Thirty-five compounds were chosen using the PASS online program. For homology modeling and molecular docking, FASTA sequences and 3D structures for protein targets were retrieved from NCBI and PDB databases. Autodock Vina in PyRx 0.8 was used for docking studies. Further, molecular dynamics simulations were performed using the IMODS server for top-ranked docked complexes. Moreover, the drug-like properties and toxicity analyses were performed using Lipinski parameters in Swiss-ADME, OSIRIS, ProTox-II, pkCSM, and StopTox servers. The results indicated that naamine D, latrunculin A and S, (+)-curcudiol, (+)-curcuphenol, aurantoside I, and hyrtimomine A had the highest binding affinity values of -8.8, -8.6, -9.8, -11.4, -8.0, -11.4, and -9.0 kcal/mol, respectively. In sum, all MNPs included in this study are good candidates against mucormycosis. (+)-curcudiol and (+)-curcuphenol are promising compounds due to their broad-spectrum target inhibition potential.


Assuntos
Antifúngicos , Produtos Biológicos , Tratamento Farmacológico da COVID-19 , Mucormicose/tratamento farmacológico , Poríferos/química , SARS-CoV-2 , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacocinética , Antifúngicos/toxicidade , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacocinética , Produtos Biológicos/toxicidade , COVID-19/complicações , Coinfecção , Proteínas Fúngicas/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mucormicose/etiologia , Testes de Toxicidade Aguda
18.
Future Microbiol ; 17: 281-291, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35152707

RESUMO

Aim: Octyl gallate (OG) loaded into a nanostructured lipid system (NLS) was tested for antifungal activity and in vitro and in vivo toxicity. Methods & Results: The features of NLS-OG were analyzed by dynamic light scattering and showed adequate size (132.1 nm) and homogeneity (polydispersity index = 0.200). OG was active against Paraccoccidioides spp., and NLS-OG did not affect antifungal activity. NLS-OG demonstrated reduced toxicity to lung cells and zebrafish embryos compared with OG, whereas NLS was toxic to hepatic cells. OG and NLS-OG did not show toxicity in a Galleria mellonella model at 20 mg/kg. All toxic concentrations were superior to MIC (antifungal activity). Conclusion: These results indicate good anti-Paracoccidioides activity and low toxicity of NLS-OG.


Plain language summary Drugs for the treatment of fungal diseases are limited in number and present side effects, drug interactions, risks for pregnant women and fungal resistance. The authors produced a derivative compound from plants called octyl gallate (OG) and then incorporated it into a nanoparticle lipid system (NLS) for better distribution in biological fluids. NLS-OG was tested against a fungus called Paracoccidioides, which causes lung infections. The toxicity profile of NLS-OG was also evaluated in lung and hepatic cells as well as novel animal models. NLS-OG presented good antifungal activity and low toxicity in lung cells and embryos.


Assuntos
Antifúngicos , Paracoccidioides , Animais , Antifúngicos/toxicidade , Ácido Gálico/análogos & derivados , Lipídeos , Peixe-Zebra
19.
Sci Total Environ ; 822: 153412, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35090921

RESUMO

Azole fungicides are widely used chemicals in agriculture and medicine. Their antifungal activity involves inhibition of steroid biosynthesis via inhibition of several cytochrome p450 enzymes. Evidence is accumulating in fish species to suggest azole fungicides perturb multiple hormone signaling pathways. The objective of this review was to comprehensively review data for azole-mediated impacts on the teleost endocrine system. We emphasize aspects of azole-induced endocrine disruption in several fish species, with special focus on the hypothalamic-pituitary-gonadal (HPG), hypothalamus-pituitary-thyroid (HPT) and hypothalamic-pituitary-adrenal (HPA) axis. Histopathological, physiological, and molecular data suggest azole fungicides at environmentally relevant concentrations and above are endocrine disruptors in fish. Endocrine disruption has been well documented for some azoles (e.g., difenconazole, fadrozole, ketoconazole, tebuconazole, triadimefon), but there are little data for others (e.g., cyproconazole, expoxiconazole, imidazole, metoconazole, nocodazole) in fish, revealing a knowledge gap in our understanding of azole toxicity. Based upon literature, computational analyses of transcriptome responses revealed progesterone-mediated oocyte maturation, insulin signaling pathway, adrenergic signaling, and metabolism of angiotensinogen may be processes disrupted by azoles. However, hormonal regulation of the sympathetic nervous system and the cardiovascular system in response to azole exposure has yet to be investigated in fish. Recommendations for studies moving forward include focus on non-steroid endocrine pathways, mechanisms of neuroendocrine disruption, and transgenerational effects of azoles on fish. This critical review identifies knowledge gaps and future directions for environmental studies focused on the effects of azoles in aquatic species.


Assuntos
Disruptores Endócrinos , Fungicidas Industriais , Animais , Antifúngicos/toxicidade , Azóis/toxicidade , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Peixes , Fungicidas Industriais/toxicidade
20.
J Med Chem ; 65(3): 2532-2547, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-35073076

RESUMO

Currently, cancer patients with microbial infection are a severe challenge in clinical treatment. To address the problem, we synthesized hemiprotonic compounds based on the unique structure of hemiprotonic nucleotide base pairs in a DNA i-motif. These compounds were produced from phenanthroline (ph) dimerization with phenanthroline as a proton receptor and ammonium as a donor. The biological activity shows that the compounds have a selective antitumor effect through inducing cell apoptosis. The molecular mechanism could be related to specific inhibition of transcription factor PLAGL2 of tumor cells, assessed by transcriptomic analysis. Moreover, results show that the hemiprotonic ph-ph+ has broad-spectrum antibacterial and antifungal activities, and drug-resistant bacteria, including methicillin-resistant Staphylococcus aureus, are sensitive to the compound. In animal models of liver cancer with fungal infection, the ph-ph+ retards proliferation of hepatoma cells in tumor-bearing mice and remedies pneumonia and encephalitis caused by Cryptococcus neoformans. The study provides a novel therapeutic candidate for cancer patients accompanied by infection.


Assuntos
Anti-Infecciosos/uso terapêutico , Antineoplásicos/uso terapêutico , Encefalite/tratamento farmacológico , Neoplasias/tratamento farmacológico , Fenantrolinas/uso terapêutico , Pneumonia/tratamento farmacológico , Animais , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/toxicidade , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/toxicidade , Antifúngicos/síntese química , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Antifúngicos/toxicidade , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Encefalite/complicações , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Neoplasias/complicações , Fenantrolinas/síntese química , Fenantrolinas/farmacologia , Fenantrolinas/toxicidade , Pneumonia/complicações , Prótons , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...