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1.
PLoS Pathog ; 17(10): e1010037, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34710198

RESUMO

The opportunistic pathogen Candida glabrata is the second most frequent causative agent of vulvovaginal candidiasis (VVC), a disease that affects 70-75% of women at least once during their life. However, C. glabrata is almost avirulent in mice and normally incapable of inflicting damage to vaginal epithelial cells in vitro. We thus proposed that host factors present in vivo may influence C. glabrata pathogenicity. We, therefore, analyzed the impact of albumin, one of the most abundant proteins of the vaginal fluid. The presence of human, but not murine, albumin dramatically increased the potential of C. glabrata to damage vaginal epithelial cells. This effect depended on macropinocytosis-mediated epithelial uptake of albumin and subsequent proteolytic processing. The enhanced pathogenicity of C. glabrata can be explained by a combination of beneficial effects for the fungus, which includes an increased access to iron, accelerated growth, and increased adhesion. Screening of C. glabrata deletion mutants revealed that Hap5, a key regulator of iron homeostasis, is essential for the albumin-augmented damage potential. The albumin-augmented pathogenicity was reversed by the addition of iron chelators and a similar increase in pathogenicity was shown by increasing the iron availability, confirming a key role of iron. Accelerated growth not only led to higher cell numbers, but also to increased fungal metabolic activity and oxidative stress resistance. Finally, the albumin-driven enhanced damage potential was associated with the expression of distinct C. glabrata virulence genes. Transcriptional responses of the epithelial cells suggested an unfolded protein response (UPR) and ER-stress responses combined with glucose starvation induced by fast growing C. glabrata cells as potential mechanisms by which cytotoxicity is mediated.Collectively, we demonstrate that albumin augments the pathogenic potential of C. glabrata during interaction with vaginal epithelial cells. This suggests a role for albumin as a key player in the pathogenesis of VVC.


Assuntos
Albuminas/metabolismo , Candida glabrata/patogenicidade , Candidíase Vulvovaginal/microbiologia , Células Epiteliais/microbiologia , Animais , Feminino , Humanos , Camundongos
3.
J Prosthodont ; 28(5): 580-586, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28872720

RESUMO

PURPOSE: Denture stomatitis (DS) is a disease characterized by inflammation and erythema of the oral mucosa areas covered by the denture. Multifactorial etiological factors contribute to DS, but it seems that Candida plays the key role. The aim of the study was to evaluate the denture sonication method to: (i) increase the possibility of diagnosing patients with Candida-associated DS; (ii) detect and identify the mixed Candida spp., and (iii) determine the Candida colony forming units (CFU) and its possible relationship with DS severity, based on Newton's classification. MATERIALS AND METHODS: The cross-sectional study conducted at the Clinic for Dental Prosthetics, Belgrade (Serbia) from June 2013 to December 2014 enrolled edentulous patients with dentures (n = 250). Patients without DS (n = 20) were the control group (CG). The patients' data were collected, and patients with DS (study group/SG) were selected and divided into SG Candida+ and SG Candida-. Based on severity of DS, the SG patients were classified in 3 groups (Newton's classification). Four sampling methods were applied to detect patients with Candida-associated DS: mucosa swab, denture swab, oral rinse, and denture sonication method. The sensitivity and specificity of denture sonication method were shown using the receiver operating characteristic (ROC) curve and the area under the curve (AUC). RESULTS: In 97 (38.8%), out of 250 clinically examined patients, DS was diagnosed. In 82 (84.5%), out of 97 mycologically examined patients, Candida-associated DS was detected when denture sonication method was applied. Additionally, using the denture sonication method we observed: (i) the largest number of Candida positive patients compared to other sampling methods (p < 0.0001); (ii) the highest number of Candida CFU/ml (105 ), and (iii) the possibility to detect mixed Candida cultures. The largest number of patients with Candida-associated DS showed type II (60%) DS, followed by type I (21%), and type III (19%) DS. CONCLUSION: The denture sonication method is easy, accurate, and sensitive, and increases the possibility of diagnosing patients with Candida-associated DS. Additionally, yeast quantification, mixed Candida spp., and non-albicans Candida were detectable when cultivation on Candida CHROMagar was performed. It was not possible using conventional methods, such as swab or oral rinse.


Assuntos
Estomatite sob Prótese , Candida , Candida albicans , Estudos Transversais , Dentaduras , Humanos , Sérvia , Sonicação
4.
Med Mycol ; 56(2): 162-171, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28482010

RESUMO

Dysbiosis of the microbiome on the airway mucosa leads to the development of chronic inflammatory and allergic disorders. The aim of this study was to consider the potential diagnostic criteria for allergic fungal rhinosinusitis (AFRS) and nonallergic fungal rhinosinusitis (FRS), and the role of fungal presence in an environment for the development of AFRS. In this study, 136 patients were divided into two groups: patients with positive specific immunoglobulin E (sIgE) and fungal finding (AFRS group), and patients with negative sIgE and positive fungal finding (FRS group). The study design included: anamnesis data, sIgE, eosinophil count and skin-prick test, rhinology and computerized tomography (CT) observation and mycological finding. Our results showed: (i) the prevalence in Serbia is: AFRS 1.3%, FRS 2.8%; (ii) 30.4% patients with sIgE+ had more often severe and recurrent chronic rhinosinusitis (CRS) (P = .005) and the presence of polyps (P = .025); (iii) 46.4% patients with sIgE+ had positive fungi on the sinonasal mucosa and were considered as AFRS; (iv) patients with AFRS had more frequent asthma (P = .024) and chronicity of CRS >10 years (P = .000). The persistent fungal presence and prolonged duration of CRS could be a silent threat for the progression of inflammation and development of FRS. Lavage with hypertonic-NaCl should be included in the everyday hygiene routine in an effort to decrease fungal load and antigenic exposure. The presence of allergological parameters and better response to corticosteroid therapy in AFRS patients should be considered as crucial diagnostic criteria for AFRS.


Assuntos
Fungos/isolamento & purificação , Micoses/diagnóstico , Rinite Alérgica Perene/diagnóstico , Sinusite/diagnóstico , Adolescente , Adulto , Idoso , Asma/diagnóstico , Doença Crônica , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/microbiologia , Pólipos Nasais/patologia , Rinite Alérgica Perene/imunologia , Rinite Alérgica Perene/microbiologia , Rinite Alérgica Perene/patologia , Sinusite/imunologia , Sinusite/microbiologia , Sinusite/patologia , Testes Cutâneos , Adulto Jovem
5.
Appl Microbiol Biotechnol ; 102(4): 1889-1901, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29330691

RESUMO

Candida spp. are leading causes of opportunistic mycoses, including life-threatening hospital-borne infections, and novel antifungals, preferably aiming targets that have not been used before, are constantly needed. Hydrazone- and guanidine-containing molecules have shown a wide range of biological activities, including recently described excellent antifungal properties. In this study, four bis-guanylhydrazone derivatives (BG1-4) were generated following a previously developed synthetic route. Anti-Candida (two C. albicans, C. glabrata, and C. parapsilosis) minimal inhibitory concentrations (MICs) of bis-guanylhydrazones were between 2 and 15.6 µg/mL. They were also effective against preformed 48-h-old C. albicans biofilms. In vitro DNA interaction, circular dichroism, and molecular docking analysis showed the great ability of these compounds to bind fungal DNA. Competition with DNA-binding stain, exposure of phosphatidylserine at the outer layer of the cytoplasmic membrane, and activation of metacaspases were shown for BG3. This pro-apoptotic effect of BG3 was only partially due to the accumulation of reactive oxygen species in C. albicans, as only twofold MIC and higher concentrations of BG3 caused depolarization of mitochondrial membrane which was accompanied by the decrease of the activity of fungal mitochondrial dehydrogenases, while the activity of oxidative stress response enzymes glutathione reductase and catalase was not significantly affected. BG3 showed synergistic activity with amphotericin B with a fractional inhibitory concentration index of 0.5. It also exerted low cytotoxicity and the ability to inhibit epithelial cell (TR146) invasion and damage by virulent C. albicans SC5314. With further developments, BG3 may further progress in the antifungal pipeline as a DNA-targeting agent.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , DNA Fúngico/efeitos dos fármacos , Guanidinas/farmacologia , Hidrazonas/farmacologia , Antifúngicos/síntese química , Apoptose , Candida/fisiologia , Dicroísmo Circular , Sinergismo Farmacológico , Guanidinas/síntese química , Hidrazonas/síntese química , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular
6.
Microbiology (Reading) ; 162(12): 2116-2125, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27902418

RESUMO

The glucocorticoid betamethasone (BM) is frequently employed in clinical practice because of its anti-inflammatory and immunosuppressive properties. In this study, we investigated the effect of BM (1 and 2 mM) on the ability of Candida albicans to adhere to, invade and damage oral, intestinal or vaginal epithelial cells, as well as to elicit cytokine and chemokine release. BM at 2 mM concentration stimulated adherence of C. albicans to vaginal cells and facilitated the invasion of intestinal and vaginal epithelia without influencing the growth rate of invading C. albicans hyphae at any type of epithelia and BM concentrations tested. In addition, BM at 2 mM concentration also augmented C. albicans-initiated cell damage of oral and intestinal cells. Furthermore, BM exposure decreased IL-6 cytokine and IL-8 chemokine release from oral and vaginal epithelial cells and also IL-6 release from intestinal epithelium after infection with C. albicans. These observations suggest that high-dose applications of BM may predispose patients to various epithelial C. albicans infections.


Assuntos
Betametasona/farmacologia , Candida albicans/efeitos dos fármacos , Candidíase/microbiologia , Células Epiteliais/microbiologia , Glucocorticoides/farmacologia , Candida albicans/crescimento & desenvolvimento , Candida albicans/fisiologia , Candidíase/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo
7.
Bioorg Med Chem Lett ; 26(1): 235-9, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26586600

RESUMO

A series of novel 3-substituted isocoumarins was prepared via Pd-catalysed coupling processes and screened in vitro for antifungal activity against Candida species. The study revealed antifungal potential of isocoumarins possessing the azole substituents, which, in some cases, showed biological properties equal to those of clinically used voriconazole. Selected compounds were also screened against voriconazole resistant Candida krusei 6258 and a clinical isolate Candida parapsilosis CA-27. Although the activity against these targets needs to be improved further, the results emphasise additional potential of this new class of antifungal compounds.


Assuntos
Antifúngicos/síntese química , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Isocumarinas/síntese química , Isocumarinas/farmacologia , Antifúngicos/química , Candida/citologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Isocumarinas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
8.
Bioorg Med Chem ; 24(6): 1277-91, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26867487

RESUMO

A series of new thiophene-based guanylhydrazones (iminoguanidines) were synthesized in high yields using a straightforward two-step procedure. The antifungal activity of compounds was evaluated against a wide range of medicaly important fungal strains including yeasts, molds, and dermatophytes in comparison to clinically used drug voriconazole. Cytotoxic properties of compounds were also determined using human lung fibroblast cell line and hemolysis assay. All guanylhydrazones showed significant activity against broad spectrum of clinically important species of Candida spp., Aspergillus fumigatus, Fusarium oxysporum, Microsporum canis and Trichophyton mentagrophytes, which was in some cases comparable or better than activity of voriconazole. More importantly, compounds 10, 11, 13, 14, 18 and 21 exhibited excellent activity against voriconazole-resistant Candida albicans CA5 with very low minimal inhibitory concentration (MIC) values <2 µg mL(-1). Derivative 14, bearing bromine on the phenyl ring, was the most effective compound with MICs ranging from 0.25 to 6.25 µg mL(-1). However, bis-guanylhydrazone 18 showed better selectivity in terms of therapeutic index values. In vivo embryotoxicity on zebrafish (Danio rerio) showed improved toxicity profile of 11, 14 and 18 in comparison to that of voriconazole. Most guanylhydrazones also inhibited C. albicans yeast to hyphal transition, essential for its biofilm formation, while 11 and 18 were able to disperse preformed Candida biofilms. All guanylhydrazones showed the equal potential to interact with genomic DNA of C. albicans in vitro, thus indicating a possible mechanism of their action, as well as possible mechanism of observed cytotoxic effects. Tested compounds did not have significant hemolytic effect and caused low liposome leakage, which excluded the cell membrane as a primary target. On the basis of computational docking experiments using both human and cytochrome P450 from Candida it was concluded that the most active guanylhydrazones had minimal structural prerequisites to interact with the cytochrome P450 14α-demethylase (CYP51). Promising guanylhydrazone derivatives also showed satisfactory pharmacokinetic profile based on molecular calculations.


Assuntos
Farmacorresistência Fúngica/efeitos dos fármacos , Guanidinas/síntese química , Guanidinas/farmacologia , Tiofenos/farmacologia , Voriconazol/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Candida/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Fusarium/efeitos dos fármacos , Guanidinas/química , Humanos , Testes de Sensibilidade Microbiana , Microsporum/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Tiofenos/química , Trichophyton/efeitos dos fármacos
9.
Mycoses ; 59(3): 167-72, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26710983

RESUMO

Despite the increasing of onychomycosis caused by Candida spp., in referent literature, there is still data insufficiency about this nail infection. The objectives of this retrospective study were to determine epidemiological characteristics of Candida onychomycosis, the antifungal susceptibility of isolated species in vitro, and to compare the results of antifungal susceptibility testing with conducted treatment in period from 2011 to the end of March 2015. Out of 761 patients who were underwent clinical and mycological examinations, 137 had Candida species isolated from nails. The dominant species was Candida albicans (C. albicans) (36.59%) followed by C. parapsilosis (23.78%), C. krusei (9.76%), and C. guilliermondii (6.71%). Antifungal susceptibility in vitro testing showed good susceptibility to antimycotics, except C. krusei, which was resistance to fluconazole (FCZ) and isolates of C. tropicalis and C. glabrata which were dose dependent to itraconazole (ITZ) and fluconazole. Evaluation of medical histories determined that combined therapy, which included pulsed systemic regimen of ITZ with topical application of clotrimazole, had better clinical outcomes regarding the proscribed only topical application of clotrimazole. Multidisciplinary approach of dermatologists and mycologists is required in solving the problem of onychomycosis, which is the dominant nail disease.


Assuntos
Candidíase/epidemiologia , Dermatoses do Pé/epidemiologia , Dermatoses da Mão/epidemiologia , Onicomicose/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Candida/classificação , Candida/isolamento & purificação , Candidíase/microbiologia , Criança , Pré-Escolar , Feminino , Dermatoses do Pé/microbiologia , Dermatoses da Mão/microbiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Unhas/microbiologia , Unhas/patologia , Onicomicose/microbiologia , Prevalência , Estudos Retrospectivos , Sérvia/epidemiologia , Distribuição por Sexo , Adulto Jovem
10.
Mycoses ; 58(2): 69-75, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25590588

RESUMO

Malassezia yeast belongs to the normal cutaneous flora and under certain conditions it causes seborrhoeic dermatitis (SD). There is no culture-based study about the presence and density of the Malassezia in SD patients in Serbia. Aim was to show the presence, species distribution and density of Malassezia in patients with SD on lesional skin (LS) and non-lesional skin (NLS) and healthy controls (HC) and to compare data between Serbia and other countries. The study included 70 HC and 60 patients with SD in the study group (SG). Isolation, identification and examination of density of Malassezia colony-forming units from LS and NLS were performed. Malassezia was found more frequently in the SG than in HC, 90% and 60%, respectively (P < 0.01). The most frequent isolates in SG on LS were M. slooffiae (26%), followed by M. globosa (17%) and M. sympodialis (17%). The yeast density was much higher on LS of SG than on NLS of SG or in the HC group (P < 0.05). Higher density of Malassezia was shown on LS of SG than on NLS of SG and HC. M. slooffiae is the most prevalent species in SD patients in Serbia. This study demonstrated a positive relationship between severity of SD and presence of Malassezia spp.


Assuntos
Dermatite Seborreica/microbiologia , Dermatomicoses/microbiologia , Malassezia/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Dermatite Seborreica/epidemiologia , Dermatomicoses/epidemiologia , Feminino , Humanos , Malassezia/crescimento & desenvolvimento , Masculino , Pessoa de Meia-Idade , Sérvia/epidemiologia , Adulto Jovem
11.
Eur Arch Otorhinolaryngol ; 272(12): 3727-34, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25631464

RESUMO

In recent years fungi are favoured as origin of chronic rhinosinusitis (CRS), especially with nasal polyps (wNP). Sensitive methods for fungal detection are still absent, therefore we used NP tissue single-cell suspension for mycology investigations in patients with recalcitrant NP (rNP) that underwent functional endoscopic sinus surgery (FESS). A prospective case-series study and culture-based mycological examination were conducted in patients who underwent FESS for the first time (ft-FESS) and those with repeated FESS (re-FESS). The study was conducted in a tertiary Otorhinolaryngology Unit of Clinical Centre of Serbia. A total of 43 consecutive patients with CRSwNP underwent FESS. Culture-based mycological examination of single-cell suspension was done on 55 NPs samples. Patient's co-morbidity data were collected. Repeated FESS was observed in 19/43 (44 %) patients (re-FESS group). Asthma and aspirin intolerance were more frequent in re-FESS than in ft-FESS group (p = 0.000, p = 0.002; respectively). Fungi were detected (wF) in 10/43 (23.3 %) patients (FESSwF group), representing 13/55 culture positive NP tissue (23.6 %). Fungal presence was higher in re-FESS than in ft-FESS group (42 and 8 %, respectively; p = 0.01). Significantly longer duration of CRS was observed in FESSwF than in fungal negative patients (p = 0.033). Predominate strain was Aspergillus flavus detected in 6/10 patients. This is the first study which analysed association of fungi in single-cell suspension of NP tissue and rNP. We demonstrate significantly higher percentage of positive fungal finding in re-FESSwF than in ft-FESSwF group. The most commonly isolated species in our patients was A. flavus.


Assuntos
Pólipos Nasais/microbiologia , Pólipos Nasais/patologia , Rinite/microbiologia , Sinusite/microbiologia , Adolescente , Adulto , Idoso , Aspergillus flavus/isolamento & purificação , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
12.
Int J Med Sci ; 11(11): 1133-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25170296

RESUMO

The fatality rate of invasive aspergillosis (IA) is still very high, especially in prolonged and untreated pulmonary cases. Aspergillus fumigatus is the main causative agent of IA and investigation of its metabolites could provide valuable insight into virulence factor(s) associated with this organism. We evaluated the A. fumigatus culture filtrate (CF) products generated during short- and long-term aerated and non-aerated conditions and tested for (i) inhibition of cysteine or serine proteases and (ii) cytotoxicity. In addition, the mathematical model was determined using response surface methodology (RSM) to estimate the influence of different fermentation conditions on A. fumigatus CF characteristics, predict enzyme inhibition and make possible correlations with in vivo conditions. Biosynthesis of A. fumigatus low molecular weight proteinaceous products (from 6.4 to 15.4 kDa) was observed after 6 days of growth under aerated and alkaline conditions. Also, only these CFs showed significant reduction in cell lines survival (Caco-2 and WISH 35.6% and 54.6%, respectively). Obtained results provide solid starting point for further studies that would include: (i) detailed chemical characterization of A. fumigatus CF, (ii) activity relationships and in vivo correlation with pathogenicity of prolonged pulmonary IA and (iii) possible use of biomolecules as diagnostic or therapeutic markers.


Assuntos
Aerobiose , Aspergillus fumigatus/metabolismo , Peptídeo Hidrolases/metabolismo , Aspergilose/microbiologia , Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/patogenicidade , Células CACO-2 , Linhagem Celular Tumoral , Meios de Cultura/farmacologia , Humanos , Técnicas In Vitro , Modelos Teóricos
13.
Mycoses ; 57(6): 380-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24438323

RESUMO

Molecular typing and antifungal susceptibility testing of 34 clinical Serbian Cryptococcus neoformans isolates from 25 patients was retrospectively performed. Amplified fragment length polymorphism (AFLP) fingerprinting was used for genotyping, whereas a novel real-time PCR was used to determine the mating- and serotype. The antifungals amphotericin B, 5-fluorocytosine, fluconazole, voriconazole, itraconazole and posaconazole were used to determine the antifungal susceptibility profiles. The majority of isolates belonged to genotype AFLP1/VNI (n = 20; 58.8%), followed by AFLP2/VNIV (n = 10; 29.4%), AFLP3/VNIII (n = 3; 8.8%) and AFLP1B/VNII (n = 1; 2.9%). All AFLP1/VNI isolates were mating-serotype αA, the sole AFLP1B/VNII isolate was found to be aA, whereas AFLP2/VNIV harboured serotype D isolates with either the a (n = 2; 5.9%) or α (n = 8; 23.5%) mating-type allele. The isolates (n = 3; 8.8%) that were found to be genotype AFLP3/VNIII had the hybrid mating- and serotype combination aA-αD. In vitro antifungal susceptibility testing showed that all isolates were susceptible to amphotericin B, voriconazole and posaconazole. Low resistance level was observed for fluconazole (n = 1; 2.9%) and 5-fluorocytosine. (n = 2; 5.8%). A large percentage of isolates was found to be susceptible dose dependent to itraconazole (n = 16; 47.1%). AFLP1/VNI was the most common genotype among clinical C. neoformans isolates from immunocompromised patients in Serbia. C. neoformans from HIV-negative patients were significantly less susceptible to 5-fluorocytosine (P < 0.01). Correlation between genotypes and antifungal susceptibility was not observed.


Assuntos
Antifúngicos/farmacologia , Criptococose/epidemiologia , Criptococose/microbiologia , Cryptococcus neoformans/classificação , Cryptococcus neoformans/efeitos dos fármacos , Tipagem Molecular , Técnicas de Tipagem Micológica , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cryptococcus neoformans/isolamento & purificação , Farmacorresistência Fúngica , Feminino , Genótipo , Humanos , Masculino , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Prevalência , Estudos Retrospectivos , Sérvia/epidemiologia
14.
Pharmaceutics ; 14(4)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35456530

RESUMO

Immobilizing antifungal polyenes such as nystatin (Nys) and amphotericin B (AmB) into biodegradable formulations is advantageous compared to free drug administration providing sustained release, reduced dosing due to localized targeting and overall reduced systemic drug toxicity. In this study, we encapsulated Nys and AmB in medium chain length polyhydroxyalkanoates (mcl-PHA) microspheres (7-8 µm in diameter). The obtained formulations have been validated for antifungal activity in vitro against a panel of pathogenic fungi including species of Candida, Aspergillus, Microsporum and Trichophyton genera and toxicity and efficacy in vivo using the zebrafish model of disseminated candidiasis. While free polyenes, especially AmB, were highly toxic to zebrafish embryos at the effective (MIC) doses, after their loading into mcl-PHA microspheres, inner organ toxicity and teratogenicity associated with both drugs were not observed, even at 100 × MIC doses. The obtained mcl-PHA/polyene formulations have successfully eradicated C. albicans infection and showed an improved therapeutic profile in zebrafish by enhancing infected embryos survival. This approach is contributing to the antifungal arsenal as polyenes, although the first broad-spectrum antifungals on the market are still the gold standard for treatment of fungal infections.

15.
Antibiotics (Basel) ; 10(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207011

RESUMO

Novel biodegradable and biocompatible formulations of "old" but "gold" drugs such as nystatin (Nys) and amphotericin B (AmB) were made using a biopolymer as a matrix. Medium chain length polyhydroxyalkanoates (mcl-PHA) were used to formulate both polyenes (Nys and AmB) in the form of films (~50 µm). Thermal properties and stability of the materials were not significantly altered by the incorporation of polyenes in mcl-PHA, but polyene containing materials were more hydrophobic. These formulations were tested in vitro against a panel of pathogenic fungi and for antibiofilm properties. The films containing 0.1 to 2 weight % polyenes showed good activity and sustained polyene release for up to 4 days. A PHA monomer, namely 3-hydroxydecanoic acid (C10-OH), was added to the films to achieve an enhanced synergistic effect with polyenes against fungal growth. Mcl-PHA based polyene formulations showed excellent growth inhibitory activity against both Candida yeasts (C. albicans ATCC 1023, C. albicans SC5314 (ATCC MYA-2876), C. parapsilosis ATCC 22019) and filamentous fungi (Aspergillus fumigatus ATCC 13073; Trichophyton mentagrophytes ATCC 9533, Microsporum gypseum ATCC 24102). All antifungal PHA film preparations prevented the formation of a C. albicans biofilm, while they were not efficient in eradication of mature biofilms, rendering them suitable for the transdermal application or as coatings of implants.

16.
Data Brief ; 35: 106928, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33850980

RESUMO

Using a comparative RNA-Sequencing based transcriptional profiling approach, responses of primary human peripheral blood mononuclear cells (PBMCs) to common human pathogenic fungi have been characterized (Bruno et al. Computational and Structural Biology Journal). Primary human PBMCs were stimulated in vitro with the fungi A. fumigatus, C. albicans, and R. oryzae after which RNA was isolated and sequenced. From raw sequencing reads differential expressed genes in response to the different fungi where calculated by comparison with unstimulated cells. By overlapping differentially expressed genes in response to the pathogenic fungi A. fumigatus, C. albicans, and R. oryzae a dataset was generated that encompasses a common response to these three distinct fungi as well as species-specific responses. Here we present datasets on these common and species-specific responses that complement the original study (Bruno et al. Computational and Structural Biology Journal). These data serve to facilitate further fundamental research on the immune response to opportunistic pathogenic fungi such as A. fumigatus, C. albicans, and R. oryzae.

17.
mBio ; 12(3): e0053121, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34154403

RESUMO

Albumin is abundant in serum but is also excreted at mucosal surfaces and enters tissues when inflammation increases vascular permeability. Host-associated opportunistic pathogens encounter albumin during commensalism and when causing infections. Considering the ubiquitous presence of albumin, we investigated its role in the pathogenesis of infections with the model human fungal pathogen, Candida albicans. Albumin was introduced in various in vitro models that mimic different stages of systemic or mucosal candidiasis, where it reduced the ability of C. albicans to damage host cells. The amphipathic toxin candidalysin mediates necrotic host cell damage induced by C. albicans. Using cellular and biophysical assays, we determined that albumin functions by neutralizing candidalysin through hydrophobic interactions. We discovered that albumin, similarly, can neutralize a variety of fungal (α-amanitin), bacterial (streptolysin O and staurosporin), and insect (melittin) hydrophobic toxins. These data suggest albumin as a defense mechanism against toxins, which can play a role in the pathogenesis of microbial infections. IMPORTANCE Albumin is the most abundant serum protein in humans. During inflammation, serum albumin levels decrease drastically, and low albumin levels are associated with poor patient outcome. Thus, albumin may have specific functions during infection. Here, we describe the ability of albumin to neutralize hydrophobic microbial toxins. We show that albumin can protect against damage induced by the pathogenic yeast C. albicans by neutralizing its cytolytic toxin candidalysin. These findings suggest that albumin is a toxin-neutralizing protein that may play a role during infections with toxin-producing microorganisms.


Assuntos
Albuminas/metabolismo , Candida albicans/patogenicidade , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno , Mucosa/microbiologia , Candidíase/microbiologia , Linhagem Celular , Células Cultivadas , Feminino , Proteínas Fúngicas/biossíntese , Células HT29 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Vagina/citologia , Fatores de Virulência
18.
Nat Microbiol ; 6(5): 643-657, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33753919

RESUMO

Vaginal candidiasis is an extremely common disease predominantly caused by four phylogenetically diverse species: Candida albicans; Candida glabrata; Candida parapsilosis; and Candida tropicalis. Using a time course infection model of vaginal epithelial cells and dual RNA sequencing, we show that these species exhibit distinct pathogenicity patterns, which are defined by highly species-specific transcriptional profiles during infection of vaginal epithelial cells. In contrast, host cells exhibit a homogeneous response to all species at the early stages of infection, which is characterized by sublethal mitochondrial signalling inducing a protective type I interferon response. At the later stages, the transcriptional response of the host diverges in a species-dependent manner. This divergence is primarily driven by the extent of epithelial damage elicited by species-specific mechanisms, such as secretion of the toxin candidalysin by C. albicans. Our results uncover a dynamic, biphasic response of vaginal epithelial cells to Candida species, which is characterized by protective mitochondria-associated type I interferon signalling and a species-specific damage-driven response.


Assuntos
Candida/genética , Candidíase Vulvovaginal/microbiologia , Células Epiteliais/imunologia , Interferon Tipo I/imunologia , Mitocôndrias/imunologia , Candida/imunologia , Candida/isolamento & purificação , Candida/patogenicidade , Candidíase Vulvovaginal/genética , Candidíase Vulvovaginal/imunologia , Células Epiteliais/microbiologia , Feminino , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Humanos , Interferon Tipo I/genética , Mitocôndrias/genética , Especificidade da Espécie , Vagina/imunologia , Vagina/microbiologia , Virulência
19.
Comput Struct Biotechnol J ; 19: 647-663, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33510868

RESUMO

Candidiasis, aspergillosis, and mucormycosis cause the majority of nosocomial fungal infections in immunocompromised patients. Using an unbiased transcriptional profiling in PBMCs exposed to the fungal species causing these infections, we found a core host response in healthy individuals that may govern effective fungal clearance: it consists of 156 transcripts, involving canonical and non-canonical immune pathways. Systematic investigation of key steps in antifungal host defense revealed fungal-specific signatures. As previously demonstrated, Candida albicans induced type I and Type II interferon-related pathways. In contrast, central pattern recognition receptor, reactive oxygen species production, and host glycolytic pathways were down-regulated in response to Rhizopus oryzae, which was associated with an ER-stress response. TLR5 was identified to be uniquely regulated by Aspergillus fumigatus and to control cytokine release in response to this fungus. In conclusion, our data reveals the transcriptional profiles induced by C. albicans, A. fumigatus, and R. oryzae, and describes both the common and specific antifungal host responses that could be exploited for novel therapeutic strategies.

20.
Trends Microbiol ; 27(12): 982-996, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31451347

RESUMO

Dysbiosis in the female genital tract (FGT) is characterized by the overgrowth of pathogenic bacterial, fungal, or protozoan members of the microbiota, leading to symptomatic or asymptomatic infections. In this review, we discuss recent advances in studies dealing with molecular mechanisms of pathogenicity factors of Gardnerella vaginalis, Mycoplasma genitalium, Mycoplasma hominis, Neisseria gonorrhoeae, Streptococcus agalactiae, Chlamydia trachomatis, Trichomonas vaginalis, and Candida spp., as well as their interactions with the host and microbiota in the various niches of the FGT. Taking a holistic approach to identifying fundamental commonalities and differences during these infections could help us to better understand reproductive tract health and improve current prevention and treatment strategies.


Assuntos
Doenças dos Genitais Femininos/microbiologia , Interações Hospedeiro-Patógeno , Microbiota , Infecções do Sistema Genital/microbiologia , Animais , Bactérias/patogenicidade , Biofilmes , Feminino , Humanos , Camundongos , Infecções por Protozoários , Infecções Sexualmente Transmissíveis/microbiologia , Leveduras/patogenicidade
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