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Fungal infections represent a serious health problem worldwide. The study evaluated the antifungal activity of 4-chlorobenzyl p-coumarate, an unprecedented semi-synthetic molecule. Docking molecular and assay experiments were conducted to determine the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC), mode of action, effect on growth, fungal death kinetics, drug association, effects on biofilm, micromorphology, and against human keratinocytes. The investigation included 16â strains of Candida spp, including C. albicans, C. krusei, C. glabrata, C. tropicalis, C. dubliniensis, C. lusitaniae, C. utilis, C. rugosa, C. guilhermondi, and C. parapsilosis. Docking analysis predicted affinity between the molecule and all tested targets. MIC and MFC values ranged from 3.9â µg/mL (13.54â µM) to 62.5â µg/mL (217.01â µM), indicating a probable effect on the plasma membrane. The molecule inhibited growth from the first hour of testing. Association with nystatin proved to be indifferent. All concentrations of the molecule reduced fungal biofilm. The compound altered fungal micromorphology. The tested compound exhibited an IC50 of 7.90±0.40â µg/mL (27.45±1.42â µM) for keratinocytes. 4-chlorobenzyl p-coumarate showed strong fungicidal effects, likely through its action on the plasma membrane and alteration of fungal micromorphology, and mildly cytotoxic to human keratinocytes.
Assuntos
Antifúngicos , Biofilmes , Candida , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Humanos , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Queratinócitos/efeitos dos fármacos , Estrutura Molecular , Relação Dose-Resposta a Droga , Ácidos Cumáricos/farmacologia , Ácidos Cumáricos/química , Ácidos Cumáricos/síntese química , Sobrevivência Celular/efeitos dos fármacosRESUMO
Geopropolis resins are produced by stingless bees (Meliponinae), developed from the collection of resinous materials, waxes and exudates, from the flora of the region where stingless bees are present, in addition to the addition of clay or earth in its composition. Several biological activities are attributed to Ethanol Extracts of Geopropolis (EEGP). The bioactive properties are associated with the complex chemical composition that the samples have. This work aims to evaluate the biological activities of the EEGP, in order to contribute with a natural therapeutic alternative, to face infections, mainly those caused by resistant strains of Staphylococcus aureus. The EEGP MIC tests showed antibacterial activity against two strains of S. aureus, both at concentrations of 550â µg/mL. The MBC performed with the inhibition values showed that the EEGP has bacteriostatic activity in both strains. Biofilm inhibition rates exhibited an average value greater than 65 % at the highest concentration. The EEGP antioxidant potential test showed good antioxidant activity (IC50) of 11.05±1.55â µg/mL. In the cytotoxicity test against HaCat cells, after 24â hours, EEGP induced cell viability at the three tested concentrations (550â µg/mL: 81.68±3.79 %; 1100â µg/mL: 67.10±3.76 %; 2200â µg/mL: 67.40±1.86 %). In view of the above, the safe use of EEGP from the brazilian northeast could be proven by the cytotoxicity test, and its use as an antioxidant and antibacterial agent has proven to be effective, as an alternative in combating oxidative stress and microorganisms such as S.â aureus, which, through the spread and ongoing evolution of drug resistance, generates an active search for effective solutions.
Assuntos
Antibacterianos , Biofilmes , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Staphylococcus aureus/efeitos dos fármacos , Animais , Abelhas , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Humanos , Biofilmes/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Própole/química , Própole/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Relação Dose-Resposta a DrogaRESUMO
The objective of this study was to evaluate the antifungal activity of free methyl 3,5 dinitrobenzoate (MDNB) and its nanoemulsion (MDNB-NE) against strains of Candida albicans. Additionally, a molecular modeling study was also carried out to propose the mechanism of action and toxicity of MDNB. These results demonstrated the MDNB-NE presented a droplet size of 181.16 ± 3.20 nm and polydispersity index of 0.30 ± 0.03. MDNB and MDNB-NE inhibited the growth of all strains with minimum inhibitory concentrations of 0.27-1.10 mM. The biological results corroborated the molecular model, which pointed to a multi-target antifungal mechanism of action for MDNB in C. albicans. The study could serve as a basis for further research involving compounds with nitro groups with antifungal.
Assuntos
Antifúngicos , Candida albicans , Nitrobenzoatos , Antifúngicos/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Objective: Evaluate the effect of a multidrug solution, adopted by a referral hospital for cancer to control and treat chemotherapy-induced oral mucositis in rats. Methods: Oral mucositis (OM) was induced by 5-Fluorouracil (5-FU), and the animals were treated with saline (nâ¯=â¯8, G1), 0.12% chlorhexidine (nâ¯=â¯8, G2); and multidrug solution (nâ¯=â¯8, G3). The animals were submitted to clinical and histological analysis of the lesion using mucosal fragments. The animals' food consumption during treatment was also evaluated. Results: Clinical improvement (pâ¯<â¯0.05) was observed in the groups treated with the multidrug solution and 0.12% chlorhexidine digluconate. In G2 and G3, there was a prevalence of reepithelialization covering <50% of the lesion. Evaluation of the inflammatory infiltrate indicated that the G1 treatment permitted an intense inflammatory response in all animals, yet this evaluation parameter was moderate in groups G2 and G3. The G3 group (pâ¯<â¯0.05) presented higher food consumption than the other groups. Conclusions: The multidrug solution improved the clinical and histological parameters of the chemotherapy-induced oral mucositis, as well as promoted an increase in food intake.
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Candida albicans is associated with serious infections in immunocompromised patients. Terpenes are natural-product derivatives, widely studied as antifungal alternatives. In a previous study reported by our group, the antifungal activity of α-pinene against C. albicans was verified; α-pinene presented an MIC between 128-512 µg/mL. In this study, we evaluate time-kill, a mechanism of action using in silico and in vitro tests, anti-biofilm activity against the Candida albicans, and toxicity against human cells (HaCaT). Results from the molecular-docking simulation demonstrated that thymidylate synthase (-52 kcal mol-1), and δ-14-sterol reductase (-44 kcal mol-1) presented the best interactions. Our in vitro results suggest that α-pinene's antifungal activity involves binding to ergosterol in the cellular membrane. In the time-kill assay, the antifungal activity was not time-dependent, and also inhibited biofilm formation, while rupturing up to 88% of existing biofilm. It was non-cytotoxic to human keratinocytes. Our study supports α-pinene as a candidate to treat fungal infections caused by C. albicans.
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STATEMENT OF PROBLEM: Cinnamaldehyde has been successfully used for the short-term disinfection of dentures; however, its long-term effects on the surface and color properties of denture base materials remain unknown. PURPOSE: The purpose of this in vitro study was to evaluate the effects of simulated immersion in cinnamaldehyde for up to 5 years on the surface roughness and color parameters of a heat-polymerized denture resin. MATERIAL AND METHODS: Eighty Ø10×5-mm disk-shaped specimens were prepared from microwave heat-polymerized polymethylmethacrylate (PMMA) and immersed in 4 solutions (n=20): TW-tap water (control), SH - 0.5% sodium hypochlorite, PX-alkaline peroxide, and CA-cinnamaldehyde (27 µg/mL). The immersion protocol simulated 104 cycles (3.5 months), 913 cycles (2.5 years), and 1825 immersion cycles (5 years) of a daily immersion cleaning protocol, with immersion times ranging from 10 to 20-minutes. Surface roughness (Sa) and the color parameters of CIELab (L∗ a∗ b∗, ΔEab), CIEDE2000 (ΔE00), and the National Bureau of Standards (NBS) were analyzed at baseline (t=0) and after the immersion cycles. The data were analyzed by 2-way analysis of variance (ANOVA) for repeated measures and the Tukey post hoc test (α=.01). RESULTS: Sa was significantly increased in all groups after 1825 cycles compared with baseline (P<.01), regardless of the solution. Only the time factor significantly affected ΔEab, ΔE00, and NBS parameters, which were below the perceptibility and acceptability thresholds. After a simulated 5-year immersion, the surface roughness and color values of CA-treated specimens were not statistically different from those of the other groups (P>.01). CONCLUSIONS: Cinnamaldehyde solution (27 µg/mL) produced minor effects on the surface roughness and color parameters of a heat-polymerized denture base resin similar to those of 0.5% sodium hypochlorite and alkaline peroxide after a 5-year simulated immersion.
Assuntos
Bases de Dentadura , Higienizadores de Dentadura , Acroleína/análogos & derivados , Resinas Acrílicas , Cor , Higienizadores de Dentadura/farmacologia , Higienizadores de Dentadura/uso terapêutico , Temperatura Alta , Imersão , Teste de Materiais , Peróxidos , Polimetil Metacrilato , Hipoclorito de Sódio/farmacologia , Propriedades de Superfície , ÁguaRESUMO
OBJECTIVE: To advance studies on the effect of a new pharmaceutical formulation for the treatment of oral fungal infections, we evaluated the safety and tolerability of orabase ointment containing cinnamaldehyde for use on the oral mucosa. MATERIAL AND METHODS: A clinical trial (phase I) was carried out on 35 individuals with healthy oral mucosa divided into three groups: ointments at 200 µg/mL, n = 12; 300 µg/mL, n = 11; and 400 µg/mL, n = 12. Product safety was assessed using three parameters: (a) clinical evolution as recorded by trained examiners; (b) evolution of the inflammatory process as registered by an exfoliative cytology exam and analyzed by trained pathologists; (c) mucosal swab to count Candida spp. colony-forming units (CFU). These parameters were analyzed both beforehand and at 15 days of treatment. RESULTS: The three ointment concentrations evaluated did not trigger inflammatory processes. The mycological analyses revealed a reduction of at least 99% in the number of Candida spp. CFU. In the exfoliative cytology analyses, the cells were found to be healthy. Participants reported a pleasant taste, yet 17% reported a slight burning sensation when applying the product. CONCLUSIONS: The ointment is safe and tolerable for use on healthy oral mucosa. TRIAL REGISTRATION: Registration number: RBR-7zwzs3. CLINICAL RELEVANCE: The ointment proved to be safe and tolerable for use on oral mucosa, encouraging studies to evaluate its clinical efficacy in patients with oral candidiasis, and contributing to a new therapeutic proposal for the treatment of fungal infections caused by Candida spp.
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Candidíase Bucal , Micoses , Acroleína/análogos & derivados , Antifúngicos/farmacologia , Candida , Candidíase Bucal/tratamento farmacológico , Candidíase Bucal/microbiologia , Carboximetilcelulose Sódica/análogos & derivados , Humanos , Micoses/tratamento farmacológico , Pomadas/farmacologiaRESUMO
OBJECTIVE: This study evaluated the antifungal activity of cinnamaldehyde on Candida spp. In vitro and in situ assays were carried out to test cinnamaldehyde for its anti-Candida effects, antibiofilm activity, effects on fungal micromorphology, antioxidant activity, and toxicity on keratinocytes and human erythrocytes. Statistical analysis was performed considering α = 5%. RESULTS: The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of cinnamaldehyde ranged from 18.91 µM to 37.83 µM. MIC values did not change in the presence of 0.8 M sorbitol, whereas an 8-fold increase was observed in the presence of ergosterol, suggesting that cinnamaldehyde may act on the cell membrane, which was subsequently confirmed by docking analysis. The action of cinnamaldehyde likely includes binding to enzymes involved in the formation of the cytoplasmic membrane in yeast cells. Cinnamaldehyde-treated microcultures showed impaired cellular development, with an expression of rare pseudo-hyphae and absence of chlamydoconidia. Cinnamaldehyde reduced biofilm adherence by 64.52% to 33.75% (p < 0.0001) at low concentrations (378.3-151.3 µM). Cinnamaldehyde did not show antioxidant properties. CONCLUSIONS: Cinnamaldehyde showed fungicidal activity through a mechanism of action likely related to ergosterol complexation; it was non-cytotoxic to keratinocytes and human erythrocytes and showed no antioxidant activity.
Assuntos
Acroleína/análogos & derivados , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/fisiologia , Acroleína/química , Acroleína/metabolismo , Acroleína/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Antioxidantes/química , Sítios de Ligação , Candida/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ergosterol/química , Ergosterol/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Sorbitol/química , Sorbitol/farmacologia , Esqualeno Mono-Oxigenase/química , Esqualeno Mono-Oxigenase/metabolismoRESUMO
BACKGROUND: Fungal infections associated with the use of dentures, like denture stomatitis, are difficult to prevent and treat. This in situ study aimed to investigate the efficacy of cinnamaldehyde for the disinfection of complete removable dentures, and the effect on the physical and mechanical properties (Vickers microhardness, color, and surface roughness) of the acrylic resin. METHODS: Acrylic resin disks were inserted into the dentures of a probabilistic sample of 33 complete denture users, that used cinnamaldehyde (27 µg/mL) and 0.5% sodium hypochlorite solutions in a 20 min/7-days protocol of dentures immersion in each solution, with a wash-out period of 7 days, to constitute a crossover-study. The disks were analyzed before and after the immersion, for the presence of microorganisms (CFU/mL) and by scanning electron microscope (SEM). Also, the surface roughness (Ra) and Vickers microhardness were measured, and color parameters were analyzed using the National Bureau of Standards (NBS) method. Data was analyzed by Wilcoxon and Friedman (microbiological evaluation), paired t-test (color and roughness) and independent t-test (Vickers hardness) (α = 0.05). RESULTS: A significant reduction (P < 0.05) in the number of microorganisms was observed for each species (total microorganisms, Streptococcus mutans, and Candida spp.), with no significant differences (P > 0.05) between hypochlorite and cinnamaldehyde. There was an increase in the roughness and a decrease in the hardness of the test specimens, with no difference between the two disinfectant substances (P > 0.05). Both hypochlorite and cinnamaldehyde also caused changes in color, considered as "perceptible" by the NBS classification, but with no significant difference between disinfectant substances (P < 0.05), and under the clinically acceptable limit (ΔE ≤ 3.7). CONCLUSION: The 27 µg/mL cinnamaldehyde solution was effective against all evaluated microorganisms and caused minor alterations in hardness, surface roughness, and color parameters, with no clinical relevance.