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1.
J Fungi (Basel) ; 9(9)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37754987

RESUMO

Candidiasis is one of the most frequent nosocomial infections affecting an increasing number of at-risk patients. Candida albicans remains the most frequent causative agent of candidiasis, but, in the last decade, C. auris has emerged as a formidable multi-drug-resistant pathogen. Both species are fully capable of forming biofilms, which contribute to resistance, increasing the urgency for new effective antifungal therapies. Repurposing existing drugs could significantly accelerate the development of novel therapies against candidiasis. Here, we have screened the Repurposing Hub library from the Broad Institute, containing over 6000 compounds, in search for inhibitors of C. albicans and C. auris biofilm formation. The primary screen identified 57 initial hits against C. albicans and 33 against C. auris. Confirmatory concentration-dependent assays were used to validate the activity of the initial hits and, at the same time, establish their anti-biofilm potency. Based on these results, ebselen, temsirolimus, and compound BAY 11-7082 emerged as the leading repositionable compounds. Subsequent experiments established their spectrum of antifungal activity against yeasts and filamentous fungi. In addition, their in vivo activity was examined in the murine models of hematogenously disseminated C. albicans and C. auris infections. Although promising, further in vitro and in vivo studies are needed to confirm their potential use for the therapy of candidiasis and possibly other fungal infections.

2.
Methods Mol Biol ; 2658: 53-64, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37024695

RESUMO

Candidiasis, infections caused by Candida spp., represents one of the most common nosocomial infections afflicting an expanding number of compromised patients. Antifungal therapeutic options are few and show limited efficacy. Moreover, biofilm formation is frequently associated with different manifestations of candidiasis and further complicates therapy. Thus, there is an urgent need for new effective therapeutic agents, particularly those with anti-biofilm activity. Here we describe the development of a novel, simple, fast, economical, and highly reproducible 384-well microtiter plate model for the formation of both Candida albicans and Candida auris biofilms and its application in high-throughput screening (HTS) techniques.


Assuntos
Candida , Candidíase , Humanos , Ensaios de Triagem em Larga Escala/métodos , Candida albicans , Antifúngicos/farmacologia , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Biofilmes , Testes de Sensibilidade Microbiana
3.
Arq. Asma, Alerg. Imunol ; 5(4): 361-370, out.dez.2021. ilus
Artigo em Inglês, Português | LILACS | ID: biblio-1399785

RESUMO

O corpo humano tende sempre a procurar um estado de homeostase, buscando o equilíbrio entre todos os sistemas. O exercício físico está presente na rotina diária de indivíduos, mesmo com objetivos diferentes, porém a influência no sistema imunológico não é muitas vezes abordada como fator relevante. O sistema imune é responsável por proteger o organismo contra infecções e doenças, podendo ser modulado perante a resposta de exercícios físicos regulares. Tendo em vista que, atualmente, existe uma preocupação maior em tornar e manter a imunidade eficiente, a prática regular e moderada do exercício pode contribuir para uma maior eficácia desse sistema, dessa forma, podendo ser considerada uma proteção ao corpo humano. O objetivo dessa revisão foi sintetizar os dados de estudos presentes na literatura que demonstram a influência do exercício físico na resposta do sistema imunológico, tornando possível compreender as alterações moleculares, fisiológicas, metabólicas e celulares que levam a um tipo específico de resposta do organismo humano.


The human body always tends to seek a homeostasis state, trying to balance all systems. Physical exercise is present in the routine of individuals even with different goals, but the influence in the immune system isnt a relevant factor. The immune system is responsible for protecting the human body against some infections and diseases, and could be modulated in response by some regular physical exercise. At the moment there is a greater concern to keep efficient immunity, a practice of regular and moderate exercise can contribute to a better effectiveness of this system, thus, it can be considered a form of protection to the human body. The objective of this review was to synthesize some data from any studies presented in the literature that demonstrate the influence of physical exercise on the immune system response. Making it possible to understand the molecular mechanisms, physiological, metabolic and cellular changes that turn to a specific type of response in the human body.


Assuntos
Humanos , Exercício Físico , Sistema Imunitário , Imunidade , Células Dendríticas , Imunoglobulinas , Células Matadoras Naturais , Linfócitos , Monócitos , Citocinas , Corpo Humano , Quimiocinas , Fatores de Proteção , Treino Aeróbico , Homeostase , Leucócitos , Macrófagos , Neutrófilos
4.
Front Microbiol ; 10: 2642, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803166

RESUMO

We have previously reported on the activity of different extracts from Astronium sp. against Candida albicans, with the hydroethanolic extract prepared from leaves of A. urundeuva, an arboreal species widely distributed in arid environments of South America and often used in folk medicine, displaying the highest in vitro activity. Here we have further evaluated the antifungal activity of this extract against strains of C. albicans and C. glabrata, the two most common etiological agents of candidiasis. The extract was tested alone and loaded into a nanostructured lipid system (10% oil phase, 10% surfactant and 80% aqueous phase, 0.5% Poloxamer 407®). In vitro susceptibility assays demonstrated the antifungal activity of the free extract and the microemulsion against both Candida species, with increased activity against C. glabrata, including collection strains and clinical isolates displaying different levels of resistance against the most common clinically used antifungal drugs. Checkerboard results showed synergism when the free extract was combined with amphotericin B against C. albicans. Serial passage experiments confirmed development of resistance to fluconazole but not to the free extract upon prolonged exposure. Although preformed biofilms were intrinsically resistant to treatment with the extract, it was able to inhibit biofilm formation by C. albicans at concentrations comparable to those inhibiting planktonic growth. Cytotoxicity assays in different cell lines as well as an alternative model using Artemia salina L. confirmed a good safety profile of the both free and loaded extracts, and an in vivo assay demonstrated the efficacy of the free and loaded extracts when used topically in a rat model of vaginal candidiasis. Overall, these results reveal the promise of the A. urundeuva leaves extract to be further investigated and developed as an antifungal.

5.
Curr Opin Microbiol ; 52: 1-6, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31085405

RESUMO

The fungal species Candida albicans is most frequently associated with biofilm formation in immune-compromised and medically compromised patients, and it is now firmly established that biofilm formation represents a major virulence factor during candidiasis. A growing body of evidence has demonstrated that C. albicans biofilm development is a highly regulated and coordinated process, where adhesive interactions, morphogenetic conversions, and consortial behavior play significant roles. Cells within the biofilms are protected from environmental stresses including host immune defenses and antifungal treatment, which carries important clinical consequences for the treatment of biofilm-associated infections. Dispersal of cells from biofilms represents one of the hallmarks of the biofilm life-style, and in the case of C. albicans dispersed cells are responsible for candidemia and dissemination leading to the establishment of invasive disease.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/crescimento & desenvolvimento , Candida albicans/patogenicidade , Candidíase/microbiologia , Candidíase/fisiopatologia , Animais , Humanos , Virulência
6.
J Biomed Nanotechnol ; 15(6): 1334-1344, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31072440

RESUMO

The treatments of oral candidiasis involve azole-based antifungals; however, the fungal resistance of these drug compounds has been detected in worldwide. Therefore, the discovery of new molecules from natural sources, such as curcumin, has been reported for the treatment of fungal diseases. However, this drug has poor solubility in aqueous solvents and presents low bioavailability. Thus, the system was designed for a low viscosity precursor of a liquid crystal phase, and saliva leads a phase behaviour increasing the viscosity of system and the residence time in the mucosa and promotes antifungal activity Formulation composed of PPG-5-CETETH-20, oleic acid and water (30, 30, 40% w/w) denominated F. This formulation was diluted with artificial saliva at 10, 20 and 30% (w/v). These formulations were characterized by polarized light microscopy (PLM), mechanical behaviour, oscillatory rheology and performance studies on mucosa. In vitro studies were performed against a standard strain (ATTC 18804) or buccal isolated clinical strains for determinate the minimum inhibitory concentrations (MIC). PLM and Small-Angle X-ray Scattering (SAXS) revealed that formulation F is lamellar mesophase, whereas its dilution with artificial saliva changed the system to anisotropic hexagonal mesophase. Textural profiles show the increasing with the dilution of precursor system. Rheological measurements show that diluted systems exhibit elastic modulus values (G') than viscous modulus (G'') and it indicates more micro-structured system. Mucoadhesive force against excised porcine oesophageal mucosa showed that systems have properties mucoadhesive. Ex vivo retention studies on porcine oesophageal mucosa exhibited an increase of 5-fold and 3-fold in the retention of curcumin from F and F30, respectively. In vitro antifungal assay against Candida albicans revealed that curcumin-loaded systems were more potent against a standard strain (ATTC 18804) and buccal isolated strains compared with a curcumin solution. Hence, the physicochemical characterization, combined with ex vivo and in vitro studies, revealed that formulation designed could form a in situ gelling mucoadhesive with buccal retention of curcumin and the increase of its antifungal activity with great potential in the treatment of oral candidiasis.


Assuntos
Candidíase Bucal , Cristais Líquidos , Administração Bucal , Animais , Curcumina , Sistemas de Liberação de Medicamentos , Espalhamento a Baixo Ângulo , Suínos , Difração de Raios X
7.
Biomed Pharmacother ; 111: 1112-1123, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30841424

RESUMO

Byrsonima intermedia is a species of bush popularly used to treat gastrointestinal disorders, such as gastric ulcers, gastritis, and diarrhea. Previous studies have revealed that the methanolic crude extract of B. intermedia leaves has gastroprotective and healing properties. In this new study, we specifically investigated two purified partitions, ethyl acetate (EtOAc) and water (AcoAq), obtained from the crude extract to characterize the antiulcer effects of these two partitions and the mechanisms of action of this medicinal plant. The healing effects of these partitions on the gastric and duodenal mucosa were assessed after ischemia-reperfusion (I/R) or acetic acid-induced injury. The involvement of tumor necrosis factor-alpha (TNF-alpha), interleukin 1ß (IL-1ß), interleukin 10 (IL-10), and myeloperoxidase (MPO) activity and glutathione (GSH) levels were determined. The antibacterial activity against Helicobacter pylori was evaluated using microdilution methods. The phytochemical analysis of AcoAq revealed a predominance of oligomeric proanthocyanidins and galloyl quinic esters, whereas EtOAc was found to contain concentrated flavonoids. Both partitions led to a significant reduction in gastric lesions, but AcoAq was more effective than EtOAc with regard to anti-Helicobacter pylori activity in addition to protecting the gastric mucosa against ethanol, non-steroidal anti-inflammatory drugs (NSAIDs) and duodenal mucosal damage induced by cysteamine. Additionally, both partitions were associated with a significant increase in gastric and duodenal healing and increased gastric mucosal GSH content after damage induced by acetic acid. On the other hand, after 6 days of treatment, EtOAc was more effective than AcoAq in ameliorating gastric damage upon initiation of the gastric I/R, which was accompanied by a significant reduction in the activity of gastric mucosal MPO, IL 1-ß and TNF-alpha, as well as an elevation in IL-10 and GSH content. These results demonstrate that the oligomeric proanthocyanidins and galloyl quinic esters present in AcoAq were more effective in the prevention of gastric and duodenal ulcers due to the antioxidant effects of these compounds, whereas the flavonoids present in EtOAc were more effective due to their anti-inflammatory activity on the gastric and duodenal tissue. All these results confirm that the rich phytochemical diversity of B. intermedia contributes to the pharmacological actions of this medicinal plant on the gastrointestinal tract in addition to its activity against H. pylori.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Malpighiaceae/química , Úlcera Péptica/tratamento farmacológico , Animais , Antiulcerosos/farmacologia , Flavonoides/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Gastrite/tratamento farmacológico , Gastrite/metabolismo , Glutationa/metabolismo , Masculino , Medicina Tradicional/métodos , Úlcera Péptica/metabolismo , Compostos Fitoquímicos/farmacologia , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Plantas Medicinais/química , Ratos , Ratos Wistar , Estômago/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
8.
Int J Nanomedicine ; 13: 1179-1213, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29520143

RESUMO

Since the dawn of civilization, it has been understood that pathogenic microorganisms cause infectious conditions in humans, which at times, may prove fatal. Among the different virulent properties of microorganisms is their ability to form biofilms, which has been directly related to the development of chronic infections with increased disease severity. A problem in the elimination of such complex structures (biofilms) is resistance to the drugs that are currently used in clinical practice, and therefore, it becomes imperative to search for new compounds that have anti-biofilm activity. In this context, nanotechnology provides secure platforms for targeted delivery of drugs to treat numerous microbial infections that are caused by biofilms. Among the many applications of such nanotechnology-based drug delivery systems is their ability to enhance the bioactive potential of therapeutic agents. The present study reports the use of important nanoparticles, such as liposomes, microemulsions, cyclodextrins, solid lipid nanoparticles, polymeric nanoparticles, and metallic nanoparticles, in controlling microbial biofilms by targeted drug delivery. Such utilization of these nanosystems has led to a better understanding of their applications and their role in combating biofilms.


Assuntos
Biofilmes/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Humanos , Lipídeos/química , Lipossomos/administração & dosagem , Lipossomos/química , Nanopartículas Metálicas/química , Nanopartículas/administração & dosagem , Nanotecnologia , Polímeros/química
9.
Int J Mol Sci ; 17(8)2016 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-27556451

RESUMO

Herbal-loaded drug delivery nanotechnological systems have been extensively studied recently. The antimicrobial activity of medicinal plants has shown better pharmacological action when such plants are loaded into a drug delivery system than when they are not loaded. Syngonanthus nitens Bong. (Rhul.) belongs to the Eriocaulaceae family and presents antiulcerogenic, antioxidant, antibacterial, and antifungal activity. The aim of this study was to evaluate the antifungal activity of Syngonanthus nitens (S. nitens) extract that was not loaded (E) or loaded (SE) into a liquid crystal precursor system (S) for the treatment of vulvovaginal candidiasis (VVC) with Candida albicans. The minimal inhibitory concentration (MIC) was determined by the microdilution technique. Additionally, we performed hyphae inhibition and biofilm tests. Finally, experimental candidiasis was evaluated in in vivo models with Wistar female rats. The results showed effective antifungal activity after incorporation into S for all strains tested, with MICs ranging from 31.2 to 62.5 µg/mL. Microscopic observation of SE revealed an absence of filamentous cells 24 h of exposure to a concentration of 31.2 µg/mL. E demonstrated no effective action against biofilms, though SE showed inhibition against biofilms of all strains. In the in vivo experiment, SE was effective in the treatment of infection after only two days of treatment and was more effective than E and amphotericin B. The S. nitens is active against Candida albicans (C. albicans) and the antifungal potential is being enhanced after incorporation into liquid crystal precursor systems (LCPS). These findings represent a promising application of SE in the treatment of VVC.


Assuntos
Antifúngicos/uso terapêutico , Candidíase Vulvovaginal/tratamento farmacológico , Eriocaulaceae/química , Nanoestruturas/química , Extratos Vegetais/uso terapêutico , Animais , Antifúngicos/química , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Candidíase Vulvovaginal/microbiologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Extratos Vegetais/química , Ratos , Ratos Wistar
10.
Molecules ; 20(12): 22534-45, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26694337

RESUMO

The aim of this study was to construct a nanostructured lipid system as a strategy to improve the in vitro antibacterial activity of copper(II) complexes. New compounds with the general formulae [CuX2(INH)2]·nH2O (X = Cl(-) and n = 1 (1); X = NCS(-) and n = 5 (2); X = NCO(-) and n = 4 (3); INH = isoniazid, a drug widely used to treat tuberculosis) derived from the reaction between the copper(II) chloride and isoniazid in the presence or absence of pseudohalide ions (NCS(-) or NCO(-)) were synthesized and characterized by infrared spectrometry, electronic absorption spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, elemental analysis, melting points and complexometry with 2,2',2'',2'''-(Ethane-1,2-diyldinitrilo)tetraacetic acid (EDTA). The characterization techniques allowed us to confirm the formation of the copper(II) complexes. The Cu(II) complexes were loaded into microemulsion (MEs) composed of 10% phase oil (cholesterol), 10% surfactant [soy oleate and Brij(®) 58 (1:2)] and 80% aqueous phase (phosphate buffer pH = 7.4) prepared by sonication. The Cu(II) complex-loaded MEs displayed sizes ranging from 158.0 ± 1.060 to 212.6 ± 1.539 nm, whereas the polydispersity index (PDI) ranged from 0.218 ± 0.007 to 0.284 ± 0.034. The antibacterial activity of the free compounds and those that were loaded into the MEs against Staphylococcus aureus ATCC(®) 25923 and Escherichia coli ATCC(®) 25922, as evaluated by a microdilution technique, and the cytotoxicity index (IC50) against the Vero cell line (ATCC(®) CCL-81(TM)) were used to calculate the selectivity index (SI). Among the free compounds, only compound 2 (MIC 500 µg/mL) showed activity for S. aureus. After loading the compounds into the MEs, the antibacterial activity of compounds 1, 2 and 3 was significantly increased against E. coli (MIC's 125, 125 and 500 µg/mL, respectively) and S. aureus (MICs 250, 500 and 125 µg/mL, respectively). The loaded compounds were less toxic against the Vero cell line, especially compound 1 (IC50 from 109.5 to 319.3 µg/mL). The compound 2- and 3-loaded MEs displayed the best SI for E. coli and S. aureus, respectively. These results indicated that the Cu(II) complex-loaded MEs were considerably more selective than the free compounds, in some cases, up to 40 times higher.


Assuntos
Antibacterianos/química , Complexos de Coordenação/química , Cobre/química , Nanoestruturas/química , Antibacterianos/farmacologia , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Staphylococcus aureus/efeitos dos fármacos
11.
Int J Nanomedicine ; 10: 5081-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26300640

RESUMO

The genus Astronium (Anacardiaceae) includes species, such as Astronium fraxinifolium, Astronium graveolens, and Astronium urundeuva, which possess anti-inflammatory, anti-ulcerogenic, healing, and antimicrobial properties. Nanostructured lipid systems are able to potentiate the action of plant extracts, reducing the required dose and side effects and improving antimicrobial activity. This work aims to evaluate a nanostructured lipid system that was developed as a strategy to improve the anti-Candida albicans activity of hydroethanolic extracts of stems and leaves from Astronium sp. The antifungal activity against C. albicans (ATCC 18804) was evaluated in vitro by a microdilution technique. In addition to the in vitro assays, the Astronium sp. that showed the best antifungal activity and selectivity index was submitted to an in vivo assay using a model of vulvovaginal candidiasis infection. In these assays, the extracts were either used alone or were incorporated into the nanostructured lipid system (comprising 10% oil phase, 10% surfactant, and 80% aqueous phase). The results indicated a minimal inhibitory concentration of 125.00 µg/mL before incorporation into the nanostructured system; this activity was even more enhanced when this extract presented a minimal inhibitory concentration of 15.62 µg/mL after its incorporation. In vivo assay dates showed that the nanostructure-incorporated extract of A. urundeuva leaves was more effective than both the unincorporated extract and the antifungal positive control (amphotericin B). These results suggest that this nanostructured lipid system can be used in a strategy to improve the in vitro and in vivo anti-C. albicans activity of hydroethanolic extracts of Astronium sp.


Assuntos
Anacardiaceae/química , Candida albicans/efeitos dos fármacos , Lipídeos/química , Nanopartículas/química , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana
12.
J Ethnopharmacol ; 172: 312-24, 2015 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-26099637

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Serjania marginata (Sapindaceae), a medicinal plant commonly found in the Brazilian Cerrado, Paraguay, Bolivia and Argentina, is also known as "cipó-uva" or "cipó-timbó". Ethnopharmacological studies indicate that the leaves from this medicinal plant are used in folk medicine to treat gastric pain. The overall objective of this study was to evaluate the gastroprotective and healing effect of the hydroalcoholic extract obtained from S. marginata (HESM) leaves using rodent experimental models. As part of the integrative study of this medicinal plant, we also evaluated the acute toxicity, antimicrobial, antidiarrheal, (anti)mutagenic, and hemodynamic effects. MATERIAL AND METHODS: We performed a pharmacological study to test the acute toxicity and antimutagenic effect (Ames assay) of the HESM. The HESM was tested against different necrosis-promoting agents and experimental manipulations, such as absolute ethanol, cysteamine, pyloric ligature, and ischemia-reperfusion (I/R) injury. The gastroprotective effect of the HESM was assessed by analyzing the gastric juice (volume, pH, total acidity) and the mucus in the gastric mucosa from rats. We assessed the levels of NO, sulfhydryl compounds, PGE2, vanilloid receptor, glutathione (GSH), and malondialdehyde (MDA), as well as the myeloperoxidase (MPO) activity. The gastric healing effects of the HESM were evaluated during 7 or 14 days of treatment. The intestinal motility, antidiarrheal action, and antibacterial effects (microdilution methods) of the HESM were also evaluated. RESULTS: The phytochemical analysis of the HESM revealed the presence of saponins, flavonoid glycosides, and tannins. The extract exhibited no sign of acute toxicity or mutagenic effect in vitro. In contrast, this extract exhibited a protective effect against the mutagenic action of direct- and indirect-acting mutagens. Only the oral administration of HESM (250mg/kg) significantly decreased the severity of gastric damage induced by ethanol (60.13%) and I/R (58.31%). The HESM exerts its gastroprotective effects by decreasing the MPO and MDA activities in the gastric tissue and by increasing the amount of adherent mucus covering the gastric mucosa. In vitro, the extract also displayed evident antimicrobial effects against Helicobacter pylori. However, the preventive effect of the HESM was not accompanied by an ulcer-healing effect. The treatment with HESM (14 days) significantly increased gastric lesions in 99% of the tested animals compared with the control group. This result represents a highly relevant piece of evidence that should resonate as an alert against the chronic use of this medicinal plant as an antiulcer in folk medicine. CONCLUSIONS: Despite the anti-H. pylori and gastroprotective actions of S. marginata in experimental models, the gastric injuries aggravation induced after chronic treatment with the HESM argues against the use of this plant species in folk medicine.


Assuntos
Antiulcerosos/farmacologia , Extratos Vegetais/farmacologia , Sapindaceae/química , Úlcera Gástrica/prevenção & controle , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Antiulcerosos/isolamento & purificação , Antiulcerosos/toxicidade , Antidiarreicos/isolamento & purificação , Antidiarreicos/farmacologia , Antidiarreicos/toxicidade , Modelos Animais de Doenças , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Masculino , Medicina Tradicional , Camundongos , Extratos Vegetais/toxicidade , Folhas de Planta , Ratos , Ratos Wistar , Fatores de Tempo , Testes de Toxicidade Aguda
13.
Int J Nanomedicine ; 10: 7455-66, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26719688

RESUMO

Vaginal infections caused by Candida krusei are a problem of extreme complexity due to the intrinsic resistance to azole drugs. The species Syngonanthus nitens (Bong.) Ruhland is a plant of the Eriocaulaceae family that has demonstrated promising antifungal activity. In phyto-formulation research, liquid crystal precursor mucoadhesive systems (LCPM) stand out as drug delivery systems for vaginal administration because they increase the activity and overcome the problems associated with plant-based medicines. Therefore, the objective of this study was to evaluate the potential of the methanolic extract of scapes of S. nitens (S. nitens extract [SNE]) and an SNE-loaded LCPM against C. krusei as prophylaxis for vulvovaginal candidiasis. LCPM formulation developed consisted of oleic acid as the oil phase (50% w/w), polyoxypropylene (5) polyoxyethylene (20) cetyl alcohol (40% w/w) as the surfactant and a polymeric dispersion containing 2.5% Carbopol(®) 974P and 2.5% polycarbophil (10% w/w) as the aqueous phase. LCPM formulation developed was characterized using polarized light microscopy, rheological analysis, and in vitro mucoadhesive studies. Different strains of C. krusei, including one standard strain (American Type Culture Collection 6258) and three clinically isolated strains from the vaginal region (CKV1, 2, and 3), were used to determine the minimum inhibitory concentration, inhibition of biofilms, and time kill. The in vivo prophylaxis assay was performed using the standard strain (American Type Culture Collection 6258). The analyses of F by polarized light microscopy and rheology showed isotropy; however, the addition of 100% artificial vaginal mucus (F100) made it more viscous and anisotropic. Moreover, the mucoadhesive strength was modified, which makes F an excellent formulation for vaginal applications. SNE was active against all strains studied, with minimum inhibitory concentration values ranging from 125 to 62.5 µg/mL; after incorporating SNE into F (FE), these values decreased to 62.5 to 31.2 µg/mL, demonstrating that incorporation into the formulation potentiated the action of SNE. Additionally, the time kill assays showed that both forms of SNE were capable of controlling growth, thereby suggesting a possible fungistatic mechanism. Unloaded SNE was not active against C. krusei biofilms, but FE was active against a clinical strain (CKV2). In vivo analysis showed that FE was able to prevent the development of infection following 10 days of administration. We concluded that the formulation developed in this study was an important vehicle for the delivery of SNE based on the improved antifungal activity in all in vitro and in vivo analyses. Furthermore, the extract incorporated into the system may serve as an important prophylactic agent against vaginal infections caused by C. krusei.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candidíase Vulvovaginal/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Eriocaulaceae/química , Cristais Líquidos , Muco/química , Extratos Vegetais/farmacologia , Animais , Antibioticoprofilaxia , Antifúngicos/química , Candidíase Vulvovaginal/microbiologia , Portadores de Fármacos , Feminino , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Wistar
14.
Ann Clin Microbiol Antimicrob ; 13: 54, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25406585

RESUMO

Throughout the genetic and physiological evolution of microorganisms, the microbiological sciences have been expanding the introduction of new therapeutic trials against microbial diseases. Special attention has been paid to the bacterium Helicobacter pylori, which induces gastric infections capable of causing damage, ranging from acute and chronic gastritis to the development of gastric cancer and death. The use of compounds with natural origins has gained popularity in scientific research focused on drug innovation against H. pylori because of their broad flexibility and low toxicity. The aim of this study was to describe the use of natural products against H. pylori in order to clarify important parameters for related fields. The study demonstrated the vast therapeutic possibilities for compounds originating from natural sources and revealed the need for innovations from future investigations to expand the therapeutic arsenal in the fight against H. pylori infection.


Assuntos
Antibacterianos/farmacologia , Produtos Biológicos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Humanos
15.
J Biomed Nanotechnol ; 10(9): 2218-43, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25992455

RESUMO

Women frequently develop disorders related to the vaginal area, including problems with the immune system, hygiene, genetic aspects and sexually transmitted diseases. Compared with other mucosal application sites, the vagina represents local effect as well as systemic drug delivery and is able to avoid the first-pass effect due to its large surface area, high blood supply and permeability to many active ingredients. It has been widely proposed that the use of drugs to treat vaginal disorders be combined with nanotechnology because nanosystems often potentiate the action of most active constituents, reducing the required dosage and side effects and improving the resulting activity in comparison with conventional treatments. Following the trend of using drug delivery systems based on nanotechology, many studies have encouraged the scientific community to turn to the development of new strategies for the vaginal administration of drugs. This study proposes to review the most common nanotechnology-based drug delivery systems that have been used to improve the effectiveness of active compounds administrated to treat vaginal disorders.


Assuntos
Nanotecnologia/métodos , Preparações Farmacêuticas/administração & dosagem , Administração Intravaginal , Animais , Emulsões/química , Feminino , Humanos , Lipossomos/química , Nanopartículas/química
16.
Int J Nanomedicine ; 9: 1-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24363556

RESUMO

Herbal medicines have been widely used around the world since ancient times. The advancement of phytochemical and phytopharmacological sciences has enabled elucidation of the composition and biological activities of several medicinal plant products. The effectiveness of many species of medicinal plants depends on the supply of active compounds. Most of the biologically active constituents of extracts, such as flavonoids, tannins, and terpenoids, are highly soluble in water, but have low absorption, because they are unable to cross the lipid membranes of the cells, have excessively high molecular size, or are poorly absorbed, resulting in loss of bioavailability and efficacy. Some extracts are not used clinically because of these obstacles. It has been widely proposed to combine herbal medicine with nanotechnology, because nanostructured systems might be able to potentiate the action of plant extracts, reducing the required dose and side effects, and improving activity. Nanosystems can deliver the active constituent at a sufficient concentration during the entire treatment period, directing it to the desired site of action. Conventional treatments do not meet these requirements. The purpose of this study is to review nanotechnology-based drug delivery systems and herbal medicines.


Assuntos
Nanocápsulas/química , Nanocápsulas/ultraestrutura , Fitoterapia/métodos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Plantas Medicinais/química , Animais , Desenho de Fármacos , Medicina Herbária/métodos , Humanos , Nanocápsulas/administração & dosagem , Nanotecnologia/métodos
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