Pythiosis is a harmful disease caused by Pythium insidiosum, an aquatic oomycete. Therapeutic protocols based on antifungal drugs are often ineffective because the cytoplasmic membrane of P. insidiosum does not contain ergosterol. Therefore, the treatment of pythiosis is still challenging, particularly making use of natural products and secondary metabolites from bacteria. In this study, xanthyletin and substances obtained from Pseudomonas stutzeri ST1302 and Klebsiella pneumoniae ST2501 exhibited anti-P. insidiosum activity and, moreover, xanthyletin was non-toxic against human cell lines. The hyphae of P. insidiosum treated with these three substances exhibited lysis holes on a rough surface and release of anamorphic material. Therefore, xanthyletin could be considered a promising alternative agent for treating cutaneous pythiosis in the near future.
- MeSH
- antifungální látky farmakologie MeSH
- antiparazitární látky farmakologie MeSH
- Bacteria chemie metabolismus MeSH
- buněčné linie MeSH
- fibroblasty účinky léků MeSH
- hyfy účinky léků ultrastruktura MeSH
- komplexní směsi MeSH
- kumariny farmakologie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- Pythium účinky léků MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Candida albicans is the main causative agent of vulvovaginal candidiasis (VVC), a common mycosis in women, relapses of which are difficult to manage due to biofilm formation. This study aimed at developing novel non-toxic compounds active against Candida spp. biofilms. We synthesised analogues of natural antifungal peptides LL-III (LL-III/43) and HAL-2 (peptide VIII) originally isolated from bee venoms and elucidated their structures by nuclear magnetic resonance spectroscopy. The haemolytic, cytotoxic, antifungal and anti-biofilm activities of LL-III/43 and peptide VIII were then tested. LL-III/43 and VIII showed moderate cytotoxicity to HUVEC-2 cells and had comparable inhibitory activity against C. albicans and non-albicans spp. The lowest minimum inhibitory concentration (MIC90) of LL-III/43 was observed towards Candida tropicalis (0.8 µM). That was 8-fold lower than that of antimycotic amphotericin B. Both peptides can be used to inhibit Candida spp. bio film f ormation. Biofilm inhibitory concentrations (BIC50) ranged from 0.9 to 58.6 µM and biofilm eradication concentrations (BEC50) for almost all tested Candida spp. strains ranged from 12.8 to 200 µM. Als o pro ven were the peptides' abilities to reduce the area colonised by biofilms , inhibit hyphae formation and permeabilise cell membranes in biofil ms . LL-III/43 and VIII are promising candidates for further development as therapeutics against VVC.
- MeSH
- amfotericin B farmakologie MeSH
- antifungální látky chemická syntéza farmakologie MeSH
- biofilmy účinky léků MeSH
- Candida účinky léků MeSH
- endoteliální buňky pupečníkové žíly (lidské) účinky léků MeSH
- hyfy účinky léků MeSH
- kandidóza vulvovaginální mikrobiologie MeSH
- kationické antimikrobiální peptidy chemická syntéza farmakologie MeSH
- kultivované buňky MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- včelí jedy chemie MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Due to the increasing number of Candida albicans' infections and the resistance of this pathogenic fungus to drugs, new therapeutic strategies are sought. One of such strategies may be the use of static magnetic field (SMF). C. albicans cultures were subjected to static magnetic field of the induction 0.5 T in the presence of fluconazole and amphotericin B. We identified a reduction of C. albicans hyphal length. Also, a statistically significant additional effect on the viability of C. albicans was revealed when SMF was combined with the antimycotic drug amphotericin B. The synergistic effect of this antimycotic and SMF may be due to the fact that amphotericin B binds to ergosterol in plasma membrane and SMF similarly to MF could influence domain orientation in plasma membrane (PM).
- MeSH
- amfotericin B farmakologie MeSH
- antifungální látky farmakologie MeSH
- Candida albicans účinky léků růst a vývoj MeSH
- flukonazol farmakologie MeSH
- hyfy účinky léků růst a vývoj MeSH
- magnetické pole * MeSH
- mikrobiální testy citlivosti MeSH
- mikrobiální viabilita účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
Farnesol (FAR) has already demonstrated an inhibitory effect on Candida albicans biofilm. The aim of this work was to determine the effectiveness of externally added FAR in combination with fluconazole (FLC) on Candida albicans biofilm and on regulation of the ergosterol genes ERG20, ERG9, and ERG11. The effectiveness of compounds was determined by MTT assay and evaluated by the minimal inhibitory concentrations reducing a sessile biofilm to 50% activity (0.5 μg/mL and 200 μmol/L for FLC and FAR, respectively). These concentrations as well as 30 and 100 μmol/L FAR were selected for a study of the effectiveness of the FAR/FLC combination. The reduction in biofilm robustness mainly caused by the presence of 200 μmol/L FAR-alone or in combination with FLC-was accompanied by a significant inhibition of the yeast-to-hyphae transition that was observed by light microscopy and CLSM. Results from qRT-PCR indicated that while 30 μmol/L FAR only slightly regulated the expression of all 3 genes in the 48-h biofilm, the presence of 200 μmol/L FAR downregulated all the tested genes. However, the addition of 0.5 μg/mL of FLC to the samples with 200 μmol/L FAR restored the downregulation of the ERG20 and ERG11 genes to the control level. Moreover, the gene ERG9 was slightly upregulated. In summary, FAR acted via multiple effects on the C. albicans biofilm, but only a higher concentration of FAR proved to be effective.
- MeSH
- antifungální látky farmakologie MeSH
- biofilmy účinky léků růst a vývoj MeSH
- Candida albicans účinky léků růst a vývoj MeSH
- ergosterol genetika metabolismus MeSH
- farnesol farmakologie MeSH
- flukonazol farmakologie MeSH
- geny hub genetika MeSH
- hyfy účinky léků MeSH
- metabolické sítě a dráhy účinky léků MeSH
- mikrobiální testy citlivosti MeSH
- regulace genové exprese u hub účinky léků MeSH
- synergismus léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Publikační typ
- časopisecké články MeSH
Candida albicans is the most common human fungal pathogen and can grow as yeast or filaments, depending on the environmental conditions. The filamentous form is of particular interest because it can play a direct role in adherence and pathogenicity. Therefore, the purpose of this study was to evaluate the effects of three clinical strains of Lactobacillus on C. albicans filamentation as well as their probiotic potential in pathogen-host interactions via an experimental candidiasis model study in Galleria mellonella. We used the reference strain Candida albicans ATCC 18804 and three clinical strains of Lactobacillus: L. rhamnosus strain 5.2, L. paracasei strain 20.3, and L. fermentum strain 20.4. First, the capacity of C. albicans to form hyphae was tested in vitro through association with the Lactobacillus strains. After that, we verified the ability of these strains to attenuate experimental candidiasis in a Galleria mellonella model through a survival curve assay. Regarding the filamentation assay, a significant reduction in hyphae formation of up to 57% was observed when C. albicans was incubated in the presence of the Lactobacillus strains, compared to a control group composed of only C. albicans. In addition, when the larvae were pretreated with Lactobacillus spp. prior to C. albicans infection, the survival rate of G. mellonela increased in all experimental groups. We concluded that Lactobacillus influences the growth and expression C. albicans virulence factors, which may interfere with the pathogenicity of these microorganisms.
- MeSH
- analýza přežití MeSH
- antibióza MeSH
- Candida albicans účinky léků růst a vývoj MeSH
- hyfy účinky léků MeSH
- kandidóza prevence a kontrola MeSH
- Lactobacillus fyziologie MeSH
- larva mikrobiologie MeSH
- modely nemocí na zvířatech MeSH
- můry mikrobiologie MeSH
- probiotika farmakologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Sclerotium rolfsii is one of the most destructive fungal plant pathogens that can infect over 500 plants and can adapt to diverse environmental conditions. The present research work was carried out to evaluate the impact of both hexa- and trivalent chromium (Cr) on growth, morphology, enzymatic characteristics, and metal accumulation in S. rolfsii under laboratory conditions. Experiments were performed in both malt extract broth and agar growth medium amended with six different concentrations (10, 20, 40, 60, 80, and 100 ppm) of each Cr(III) and Cr(VI) ions inoculated with fungus and incubated for 6-7 days at 25 ± 3 °C. In broth medium, the total protein content was declined and activities of antioxidant enzymes were increased with an increase in metal concentrations. Lower concentrations (10 ppm) of the metal ions stimulated the growth of fungus and higher concentrations (60-100) inhibited it. The Fourier transform infrared spectroscopy (FTIR) assessment showed hydroxyl, carboxyl, and amine groups as major metal binding sites. In agar medium, tolerance index was decreased up to 0.56 at 10-80 ppm of Cr(III) and up to 0.62 at 10-60 ppm of Cr(VI). Considerable modifications were observed in hyphal and sclerotial morphology with an increase in concentration of metal ions. The current study concluded that interference of Cr with growth and physiological process of S. rolfsii could affect its infection level on its host plant. This study provides important information regarding cultivation of susceptible plant varieties in Cr-polluted soil as evidenced by pathogen growth up to 50 ppm of Cr(III) and Cr(VI) ions.
- MeSH
- antioxidancia analýza MeSH
- Basidiomycota cytologie účinky léků enzymologie fyziologie MeSH
- chrom metabolismus MeSH
- hyfy cytologie účinky léků MeSH
- inhibitory růstu metabolismus MeSH
- kultivační média chemie MeSH
- oxidační stres * MeSH
- růstové látky metabolismus MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
Coniochaeta pulveracea is a dimorphic lignicolous fungus that has mostly been isolated from decaying wood. However, relatively little work was conducted on the conditions for the dimorphic switch or the biological interactions of the fungus in its yeast-like microcyclic growth phase. Therefore, in this study, the microcyclic conidiation of C. pulveracea strains and representatives of the closely related species, Coniochaeta boothii and Coniochaeta subcorticalis, was studied under different environmental conditions. The strains were found to exhibit hyphal growth on solid substrates and underwent a dimorphic switch to produce microcycle conidiation upon transfer to a liquid medium which differed in physico-chemical composition compared to the original solid medium. Factors that were found to contribute to this dimorphic switch were temperature, pH and the presence of complex nitrogen sources such as casamino acids and peptone in the medium. However, C. pulveracea showed intraspecific differences with regard to its response to changes in the physico-chemical environment. The interactions of microcyclic Coniochaeta strains with selected yeasts, such as representatives of Meyerozyma guilliermondii and Cryptococcus neoformans, were subsequently studied in complex liquid media and it was found that, depending on medium composition, the microcyclic Coniochaeta exerted different effects on the different yeasts strains. In some co-cultures, a positive effect on yeast growth was observed, whilst in other cases microcyclic Coniochaeta inhibited yeast growth.
- MeSH
- Ascomycota cytologie účinky léků růst a vývoj účinky záření MeSH
- Cryptococcus neoformans růst a vývoj MeSH
- hyfy cytologie účinky léků růst a vývoj účinky záření MeSH
- koncentrace vodíkových iontů MeSH
- kultivační média chemie MeSH
- mikrobiální interakce MeSH
- Saccharomycetales růst a vývoj MeSH
- sloučeniny dusíku metabolismus MeSH
- spory hub cytologie účinky léků růst a vývoj účinky záření MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
Quorum sensing (QS) regulates group behaviors of Candida albicans such as biofilm, hyphal growth, and virulence factors. The sesquiterpene alcohol farnesol, a QS molecule produced by C. albicans, is known to regulate the expression of virulence weapons of this fungus. Fluconazole (FCZ) is a broad-spectrum antifungal drug that is used for the treatment of C. albicans infections. While FCZ can be cytotoxic at high concentrations, our results show that at much lower concentrations, quercetin (QC), a dietary flavonoid isolated from an edible lichen (Usnea longissima), can be implemented as a sensitizing agent for FCZ-resistant C. albicans NBC099, enhancing the efficacy of FCZ. QC enhanced FCZ-mediated cell killing of NBC099 and also induced cell death. These experiments indicated that the combined application of both drugs was FCZ dose dependent rather than QC dose dependent. In addition, we found that QC strongly suppressed the production of virulence weapons-biofilm formation, hyphal development, phospholipase, proteinase, esterase, and hemolytic activity. Treatment with QC also increased FCZ-mediated cell death in NBC099 biofilms. Interestingly, we also found that QC enhances the anticandidal activity of FCZ by inducing apoptotic cell death. We have also established that this sensitization is reliant on the farnesol response generated by QC. Molecular docking studies also support this conclusion and suggest that QC can form hydrogen bonds with Gln969, Thr1105, Ser1108, Arg1109, Asn1110, and Gly1061 in the ATP binding pocket of adenylate cyclase. Thus, this QS-mediated combined sensitizer (QC)-anticandidal agent (FCZ) strategy may be a novel way to enhance the efficacy of FCZ-based therapy of C. albicans infections.
- MeSH
- antifungální látky farmakologie MeSH
- antioxidancia farmakologie MeSH
- apoptóza účinky léků MeSH
- biofilmy účinky léků MeSH
- Candida albicans účinky léků MeSH
- faktory virulence metabolismus MeSH
- flukonazol farmakologie MeSH
- fungální léková rezistence účinky léků MeSH
- hyfy účinky léků MeSH
- mikrobiální testy citlivosti MeSH
- quercetin farmakologie MeSH
- quorum sensing účinky léků MeSH
- Usnea chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
