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1.
Biotechnol Lett ; 44(10): 1217-1230, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057882

RESUMO

Ergosterol as a primary metabolite and precursor of vitamin D2, is the most plentiful mycosterols in fungal cell membrane. Process optimization to increase the yield and productivity of biological products is a topic of interest. Ultrasonic waves have many applications in biotechnology, like cell disruption, and enhancement of primary and secondary metabolites production. This study disclosed an optimal condition for ultrasound-assisted production (UAP) of ergosterol from Penicillium brevicompactum MUCL 19,011 using L9 Taguchi statistical method. The intensity (IS), time of sonication (TS), treatment frequency (TF), and number of days of treatment (DT) were allocated to study the effects of ultrasound on ergosterol production. The results were analyzed using Minitab version 19. The maximum ergosterol, 11 mg/g cell dry weight (CDW), was produced on the tenth day while all factors were at a low level. The days of treatment with a contribution of 45.48% was the most significant factor for ergosterol production. For the first time, this study revealed the positive effect of ultrasound on the production of ergosterol. Ergosterol production increased 73% (4.63 mg/g CDW) after process optimization. Finally, a mathematical model of ultrasound factors with a regression coefficient of R2 = 0.978 was obtained for the ergosterol production during ultrasound treatment.


Assuntos
Produtos Biológicos , Penicillium , Produtos Biológicos/metabolismo , Ergocalciferóis/metabolismo , Ergosterol/metabolismo , Penicillium/genética , Penicillium/metabolismo
2.
World J Microbiol Biotechnol ; 38(12): 224, 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36114903

RESUMO

Candida albicans is a common human fungal pathogen that colonizes mucosa and develops biofilm in the oral cavity that causes oral candidiasis. It has been reported that cytochrome P450 enzyme (CYP51), a vital part of the ergosterol synthesis cascade, is associated with Candida infections and its biofilm formation. Thidiazuron, a phenyl-urea cytokinin, exhibits anti-senescence and elicitor activity against fungal infection in plants. However, how Thidiazuron impacts C. albicans biofilm formation is still uncertain. Here, we aimed to investigate the effects of a Thidiazuron against the growth and biofilm formation properties of C. albicans using in silico and in vitro experimental approaches. A preliminary molecular docking study revealed potential interaction between Thidiazuron and amino acid residues of CYP51. Further in vitro antifungal susceptibility test, scanning electron microscopy (SEM) and time kill analysis revealed the anti-fungal activity of Thidiazuron in both dose and time-dependent manner. Crystal violet staining, 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction assay revealed 50% inhibition in C. albicans biofilm by Thidiazuron at concentrations 11 and 19 µM respectively. Acridine orange staining assay visually confirmed the biofilm inhibitory potential of Thidiazuron. The gene expression study showed that Thidiazuron treatment down regulated the expression of genes involved in ergosterol synthesis (ERG3, ERG11, ERG25), cell adhesion (ASL3, EAP1), and hyphae development (EFG1, HWP1, SAP5) in C. albicans. Wherease, the expression of negative transcription regulator of hyphae (NRG1) was upregulated (5.7-fold) by Thidiazuron treatment. Collectively, our data suggest that Thidiazuron is a robust antifungal compound and an outstanding biofilm inhibitor, which may promise further therapeutic development due to CYP51 binding and inhibition of ergosterol formation against C. albicans.


Assuntos
Antifúngicos , Candida albicans , Laranja de Acridina/farmacologia , Aminoácidos/farmacologia , Antifúngicos/farmacologia , Biofilmes , Citocininas , Ergosterol/farmacologia , Violeta Genciana/farmacologia , Humanos , Simulação de Acoplamento Molecular , Compostos de Fenilureia/farmacologia , Tiadiazóis
3.
J Med Chem ; 65(18): 12219-12239, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36074863

RESUMO

The design of novel dual-target (COX-2/CYP51) inhibitors was proposed in the study, and three series of compounds were constructed though the pathway of skeleton screening and combination; their molecular structures were synthesized and evaluated. Most of the compounds exhibited significant antifungal ability. Among them, potential compounds (10a-2, 16b-3) with excellent antifungal and anti-drug-resistant fungal ability (MIC50, 0.125-2.0 µg/mL) were selected for the subsequent mechanistic study. On the one hand, these compounds could block the ergosterol biosynthesis pathway by inhibiting CYP51 and influence the internal physiological function of fungal cells, which included the increase of the ROS level, the anomaly of ΔΨm, and the emergence of an apoptotic state. On the other hand, these compounds also effectively showed COX-2 inhibition ability, eliminated the inflammatory reaction of the infected region, and activated the body's immune function. In summary, this study not only provided a novel antifungal drug design pathway but also discovered excellent target compounds.


Assuntos
Inibidores de 14-alfa Desmetilase , Doenças Transmissíveis , Inibidores de 14-alfa Desmetilase/química , Inibidores de 14-alfa Desmetilase/farmacologia , Inibidores de 14-alfa Desmetilase/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida albicans , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ergosterol/farmacologia , Testes de Sensibilidade Microbiana , Espécies Reativas de Oxigênio/metabolismo
4.
Pestic Biochem Physiol ; 187: 105214, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36127040

RESUMO

This study aimed to improve the stability of Cinnamomum tamala essential oil (CTEO) via encapsulating into chitosan nanoemulsion (CsNe) through an ionic-gelation technique and explore its food preservative efficacy against aflatoxigenic strain of Aspergillus flavus (AFLHPSi-1, isolated from stored millet), aflatoxin B1 (AFB1) contamination, and lipid peroxidation, causing qualitative deterioration of stored millets. The CTEO was characterized through gas chromatography-mass spectrometry (GC-MS) analysis that confirmed the presence of linalool as a major component occupying approximately 82.64% of the total oil. The synthesized nanoparticles were characterized through scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analysis. The encapsulation efficiency (EE) and loading capacity (LC) of CTEO-CsNe were found to be 97.71% and 3.33%, respectively. In vitro release study showed a biphasic release pattern: with an initial burst release followed by a controlled release of CTEO. During investigation of efficacy, the CTEO-CsNe caused complete inhibition of A. flavus growth, and AFB1 biosynthesis at 1.0 and 0.8 µL/mL, respectively. The CTEO-CsNe exhibited its antifungal mode of action by altering fungal plasma membrane integrity (ergosterol inhibition) and permeability (leakage of important cellular constituents), and antiaflatoxigenic mode of action by inhibiting cellular methylglyoxal biosynthesis. CTEO-CsNe showed high free radical scavenging capacity (IC50 = 5.08 and 2.56 µL/mL) against DPPH•+ and ABTS•+ radicals, respectively. In addition, CTEO-CsNe presented remarkable preservative efficacy, inhibiting AFB1 and lipid peroxidation in model food system (Setaria italica) without altering their organoleptic properties. Based on overall results, CTEO-CsNe can be recommended as a novel shelf-life enhancer of stored millet samples.


Assuntos
Quitosana , Cinnamomum , Óleos Voláteis , Aflatoxina B1/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Quitosana/química , Quitosana/farmacologia , Cinnamomum/metabolismo , Preparações de Ação Retardada , Grão Comestível , Ergosterol , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Radicais Livres , Milhetes/metabolismo , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Aldeído Pirúvico
5.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36077373

RESUMO

Opportunistic pathogen Candida albicans causes systemic infections named candidiasis. Due to the increasing number of multi-drug resistant clinical isolates of Candida sp., currently employed antifungals (e.g., azoles) are insufficient for combating fungal infection. One of the resistance mechanisms toward azoles is increased expression of plasma membrane (PM) transporters (e.g., Cdr1p), and such an effect was observed in C. albicans clinical isolates. At the same time, it has been proven that a decrease in PMs sphingolipids (SLs) content correlates with altered sensitivity to azoles and diminished Cdr1p levels. This indicates an important role for SL in maintaining the properties of PM and gaining resistance to antifungal agents. Here, we prove using a novel spot variation fluorescence correlation spectroscopy (svFCS) technique that CaCdr1p localizes in detergent resistant microdomains (DRMs). Immunoblot analysis confirmed the localization of CaCdr1p in DRMs fraction in both the C. albicans WT and erg11Δ/Δ strains after 14 and 24 h of culture. We also show that the C. albicanserg11Δ/Δ strain is more sensitive to the inhibitor of SLs synthesis; aureobasidin A (AbA). AbA treatment leads to a diminished amount of SLs in C. albicans WT and erg11Δ/Δ PM, while, for C. albicanserg11Δ/Δ, the general levels of mannose-inositol-P-ceramide and inositol-P-ceramide are significantly lower than for the C. albicans WT strain. Simultaneously, the level of ergosterol in the C. albicans WT strain after adding of AbA remains unchanged, compared to the control conditions. Analysis of PM permeabilization revealed that treatment with AbA correlates with the disruption of PM integrity in C. albicanserg11Δ/Δ but not in the C. albicans WT strain. Additionally, in the C. albicans WT strain, we observed lower activity of H+-ATPase, correlated with the delocalization of both CaCdr1p and CaPma1p.


Assuntos
Candida albicans , Ergosterol , Adenosina Trifosfatases/metabolismo , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Azóis/farmacologia , Membrana Celular/metabolismo , Ceramidas/metabolismo , Farmacorresistência Fúngica , Ergosterol/metabolismo , Proteínas Fúngicas/metabolismo , Inositol/farmacologia , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Esfingolipídeos/metabolismo
6.
Molecules ; 27(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36080385

RESUMO

Vitamin D's role in combating the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), the virus causing COVID-19, has been established in unveiling viable inhibitors of COVID-19. The current study investigated the role of pre and pro-vitamin D bioactives from edible mushrooms against Mpro and PLpro proteases of SARS-CoV-2 by computational experiments. The bioactives of mushrooms, specifically ergosterol (provitamin D2), 7-dehydrocholesterol (provitamin-D3), 22,23-dihydroergocalciferol (provitamin-D4), cholecalciferol (vitamin-D3), and ergocalciferol (vitamin D2) were screened against Mpro and PLpro. Molecular docking analyses of the generated bioactive protease complexes unravelled the differential docking energies, which ranged from -7.5 kcal/mol to -4.5 kcal/mol. Ergosterol exhibited the lowest binding energy (-7.5 kcal/mol) against Mpro and PLpro (-5.9 kcal/mol). The Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) and MD simulation analyses indicated that the generated complexes were stable, thus affirming the putative binding of the bioactives to viral proteases. Considering the pivotal role of vitamin D bioactives, their direct interactions against SARS-CoV-2 proteases highlight the promising role of bioactives present in mushrooms as potent nutraceuticals against COVID-19.


Assuntos
Agaricales , COVID-19 , Agaricales/metabolismo , COVID-19/tratamento farmacológico , Endopeptidases/metabolismo , Ergosterol , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptídeo Hidrolases/química , Inibidores de Proteases/química , Provitaminas , SARS-CoV-2 , Proteínas não Estruturais Virais/metabolismo , Vitamina D/farmacologia
7.
Bioresour Technol ; 362: 127878, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055542

RESUMO

Ergosterol is an important precursor in the pharmaceutical industry for the production of numerous drugs. In this study, Kluyveromyces marxianus that showed more potential for ergosterol production than some other yeasts was reported. The effects of transcription factors UPC2, MOT3, and ROX1 of K. marxianus on ergosterol synthesis were explored, and a Upc2-overexpressing strain produced 1.78 times more ergosterol (167.33 mg/L) than the wild-type strain (60.04 mg/L). A total of 239.98 mg/L ergosterol was produced when glucose was replaced with fructose to limit ethanol production. Enhanced aeration increased ergosterol titer from 63.09 mg/L to 128.46 mg/L at 42 °C. The ergosterol titer reached 304.37 mg/L in a shake flask at 37 °C, or 1124.38 and 948.32 mg/L at 37 °C and 42 °C, respectively, in a 5 L bioreactor, using Jerusalem artichoke tubers as the sole carbon source. This study establishes a platform for ergosterol biosynthesis using inexpensive materials.


Assuntos
Helianthus , Kluyveromyces , Ergosterol , Fermentação , Helianthus/genética , Kluyveromyces/genética , Temperatura
8.
ACS Infect Dis ; 8(9): 1815-1822, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36036536

RESUMO

Cationic amphiphiles have been reported to show broad antimicrobial activity. The potential for antimicrobial resistance to these molecules is low owing to their general cell membrane permeabilizing mode of action. However, their applications are often limited by toxicity resulting from their low selectivity for microbial cell membranes. Herein, we report a library of cationic, steroid-based imidazolium amphiphiles that show tunable antifungal activity in a variety of fungal pathogens of the genus Candida. We show that adoption of an ergosterol-derived backbone increases antifungal activity while modestly affecting hemolytic activity, thereby increasing overall selectivity by more than 8-fold in comparison to cholesterol-derived imidazolium salts. We hypothesize that this effect is caused by a privileged integration of the ergosterol-derived salts into fungal membranes leading to increased membrane disorder. We propose that these findings offer a useful platform for the development of improved amphiphilic fungicides.


Assuntos
Antifúngicos , Sais , Antifúngicos/farmacologia , Candida , Cátions/farmacologia , Ergosterol , Esteroides/farmacologia
9.
Biomed Pharmacother ; 154: 113596, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36030584

RESUMO

Neuroinflammation is a brain pathology that involves the expression of high levels of pro-inflammatory mediators, including tumor necrosis factor-alpha (TNF-α). An excessive TNF-α expression could result in neuronal cell death and subsequently lead to neurodegeneration. Auricularia polytricha (AP; an edible mushroom) has been reported as a rich source of ergosterol with several medicinal benefits. The current study reports on the neuroprotective effects of AP extracts and ergosterol against the TNF-α-induced HT-22 hippocampal cell injury. The hexane extract of AP (APH) demonstrated a neuroprotective effect against the TNF-α-induced HT-22 cell toxicity, taking place through the activation of the antioxidant pathway. Ergosterol, a major component of APH, could attenuate the toxicity of TNF-α on HT-22 cells, by increasing the expression of a major antioxidant enzyme (superoxide dismutase-1) and by facilitating the scavenging of reactive oxygen species through antioxidant signaling. Moreover, an antibody array was performed to screen the possible molecular targets of ergosterol in HT-22 cells exposed to TNF-α. Based on the antibody array, the phospho-Akt was activated in the presence of ergosterol, and this finding was also supported by Western blotting analysis. Furthermore, ergosterol inhibited the transcriptional expressions of the glutamate ionotropic receptor N-methyl-D-aspartate (NMDA) type subunit 2B gene (Grin2b) through an early growth response-1 (EGR-1) overexpression in TNF-α-treated HT-22 cells. Our findings suggest that a novel therapeutic effect of AP and ergosterol against neuroinflammation, that it is mediated by an NMDA gene modulation occurring through the overexpression of the EGR-1 transcription factor.


Assuntos
Fármacos Neuroprotetores , Antioxidantes/farmacologia , Ergosterol/farmacologia , Ácido Glutâmico , Hipocampo , N-Metilaspartato/farmacologia , Fármacos Neuroprotetores/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
10.
Biochim Biophys Acta Biomembr ; 1864(11): 184012, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35914570

RESUMO

Natamycin is a polyene macrolide, widely employed to treat fungal keratitis and other yeast infections as well as to protect food products against fungal molds. In contrast to other polyene macrolides, such as nystatin or amphotericin B, natamycin does not form pores in yeast membranes, and its mode of action is not well understood. Here, we have employed a variety of spectroscopic methods, computational modeling, and membrane reconstitution to study the molecular interactions of natamycin underlying its antifungal activity. We find that natamycin forms aggregates in an aqueous solution with strongly altered optical properties compared to monomeric natamycin. Interaction of natamycin with model membranes results in a concentration-dependent fluorescence increase which is more pronounced for ergosterol- compared to cholesterol-containing membranes up to 20 mol% sterol. Evidence for formation of specific ergosterol-natamycin complexes in the bilayer is provided. Using nuclear magnetic resonance (NMR) and electron spin resonance (ESR) spectroscopy, we find that natamycin sequesters sterols, thereby interfering with their well-known ability to order acyl chains in lipid bilayers. This effect is more pronounced for membranes containing the sterol of fungi, ergosterol, compared to those containing mammalian cholesterol. Natamycin interferes with ergosterol-dependent transport of lysine by the yeast transporter Lyp1, which we propose to be due to the sequestering of ergosterol, a mechanism that also affects other plasma membrane proteins. Our results provide a mechanistic explanation for the selective antifungal activity of natamycin, which can set the stage for rational design of novel polyenes in the future.


Assuntos
Natamicina , Proteínas de Saccharomyces cerevisiae , Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Antibacterianos/metabolismo , Antifúngicos/química , Colesterol/química , Ergosterol/química , Lisina/metabolismo , Natamicina/metabolismo , Natamicina/farmacologia , Polienos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Esteróis/metabolismo
11.
Microb Pathog ; 170: 105696, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35921954

RESUMO

Vulvovaginal candidiasis (VVC) is a prevalent infection of the genitourinary tract affecting millions of women worldwide. In the present study, the importance of virulence factors, ERG11 gene mutations, ERG11 gene expression, and plasma membrane ergosterol content for fluconazole resistance in Candida species was investigated in 200 women suspected of vulvovaginitis. Isolated Candida species were identified using the ITS-restriction fragment length polymorphism (ITS-RFLP) technique. Antifungal susceptibility testing was performed according to the CLSI document. ERG11 gene expression was analyzed using real-time PCR. ERG11 gene mutation analysis was performed using sequencing methods, and the ergosterol content of the cell membrane was determined in fluconazole-resistant isolates. Furthermore, the production of phospholipase and proteinase enzymes was evaluated in recurrent and non-recurrent infections. VVC was diagnosed in 101 (50.5%) of the 200 clinical cases, of which 21 (20.8%) were confirmed as RVVC. Candida albicans was the most prevalent species, followed by C. glabrata, C. tropicalis, C. krusei, C. parapsilosis, and C. guilliermondii. Ketoconazole and fluconazole were the most effective drugs against C. albicans among five tested antifungals with MIC ranges between 0.06 and 16 µg/mL and 0.25-64 µg/mL. Substitutions of A114S, Y257H, T123I and A114V were detected in fluconazole-resistant C. albicans. The ergosterol content of the fungal cell membrane and the mean levels of ERG11 gene expression transcript were higher in fluconazole-resistant C. albicans isolates obtained from RVVC than in those obtained from VVC cases. Phospholipase and proteinase were produced in different amounts in all Candida species isolated from VVC and RVVC cases. In this review, our results demonstrated that several molecular mechanisms, including ERG11 gene expression, changes in the cell membrane ergosterol content, and mutations in ERG11 gene alone or simultaneously involved in fluconazole resistance of C. albicans species and the recurrence of VVC.


Assuntos
Antifúngicos , Candidíase Vulvovaginal , Proteínas Fúngicas/metabolismo , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Candida albicans , Candida glabrata , Candida parapsilosis , Candida tropicalis , Candidíase Vulvovaginal/microbiologia , Farmacorresistência Fúngica/genética , Ergosterol/farmacologia , Feminino , Fluconazol/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Mutação , Peptídeo Hidrolases/genética , Fosfolipases/genética
12.
FEMS Yeast Res ; 22(1)2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-35932192

RESUMO

Zygosaccharomyces rouxii is an osmotolerant and halotolerant yeast that can participate in fermentation. To understand the mechanisms of salt and sugar tolerance, the transcription levels of Z. rouxii M 2013310 under 180 g/L NaCl stress and 600 g/L glucose stress were measured. The transcriptome analysis showed that 2227 differentially expressed genes (DEGs) were identified under 180 g/L NaCl stress, 1530 DEGs were identified under 600 g/L glucose stress, and 1278 DEGs were identified under both stress conditions. Then, KEGG enrichment analyses of these genes indicated that 53.3% of the upregulated genes were involved in the ergosterol synthesis pathway. Subsequently, quantitative PCR was used to verify the results, which showed that the genes of the ergosterol synthesis pathway were significantly upregulated under 180 g/L NaCl stress. Finally, further quantitative testing of ergosterol and spotting assays revealed that Z. rouxii M 2013310 increased the amount of ergosterol in response to high salt stress. These results highlighted the functional differences in ergosterol under sugar stress and salt stress, which contributes to our understanding of the tolerance mechanisms of salt and sugar in Z. rouxii.


Assuntos
Zygosaccharomyces , Ergosterol/metabolismo , Glucose/metabolismo , Saccharomyces cerevisiae/genética , Saccharomycetales , Cloreto de Sódio/metabolismo , Açúcares/metabolismo , Zygosaccharomyces/fisiologia
13.
Microbiol Spectr ; 10(4): e0077622, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35867406

RESUMO

Candida glabrata is increasingly isolated from blood cultures, and multidrug-resistant isolates have important implications for therapy. This study describes a cholesterol-dependent clinical C. glabrata isolate (ML72254) that did not grow without blood (containing cholesterol) on routine mycological media and that showed azole and amphotericin B (AmB) resistance. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and whole-genome sequencing (WGS) were used for species identification. A modified Etest method (Mueller-Hinton agar supplemented with 5% sheep blood) was used for antifungal susceptibility testing. WGS data were processed via the Galaxy platform, and the genomic variations of ML72254 were retrieved. A computational biology workflow utilizing web-based applications (PROVEAN, AlphaFold Colab, and Missense3D) was constructed to predict possible deleterious effects of these missense variations on protein functions. The predictive ability of this workflow was tested with previously reported missense variations in ergosterol synthesis genes of C. glabrata. ML72254 was identified as C. glabrata sensu stricto with MALDI-TOF, and WGS confirmed this identification. The MICs of fluconazole, voriconazole, and amphotericin B were >256, >32, and >32 µg/mL, respectively. A novel frameshift mutation in the ERG1 gene (Pro314fs) and many missense variations were detected in the ergosterol synthesis genes. None of the missense variations in the ML72254 ergosterol synthesis genes were deleterious, and the Pro314fs mutation was identified as the causative molecular change for a cholesterol-dependent and multidrug-resistant phenotype. This study verified that web-based computational biology solutions can be powerful tools for examining the possible impacts of missense mutations in C. glabrata. IMPORTANCE In this study, a cholesterol-dependent C. glabrata clinical isolate that confers azole and AmB resistance was investigated using artificial intelligence (AI) technologies and cloud computing applications. This is the first of the known cholesterol-dependent C. glabrata isolate to be found in Turkey. Cholesterol-dependent C. glabrata isolates are rarely isolated in clinical samples; they can easily be overlooked during routine laboratory procedures. Microbiologists therefore need to be alert when discrepancies occur between microscopic examination and growth on routine media. In addition, because these isolates confer antifungal resistance, patient management requires extra care.


Assuntos
Anfotericina B , Candida glabrata , Anfotericina B/metabolismo , Anfotericina B/farmacologia , Animais , Antifúngicos/farmacologia , Inteligência Artificial , Azóis/metabolismo , Azóis/farmacologia , Candida glabrata/genética , Colesterol/metabolismo , Colesterol/farmacologia , Biologia Computacional , Farmacorresistência Fúngica/genética , Resistência a Múltiplos Medicamentos , Ergosterol/metabolismo , Testes de Sensibilidade Microbiana , Ovinos
14.
Med Mycol ; 60(8)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35896502

RESUMO

Onychomycosis is a nail infection caused by Trichophyton interdigitale and other fungi, which can be treated with topical amorolfine (AMR) and ciclopirox olamine (CPX). Although these drugs are widely used, little is known about the role of reactive oxygen (ROS) and nitrogen (RNS) in their mechanism of action. To better understand the effects of AMR and CPX in dermatophytes, we evaluated whether they act through the production of ROS and peroxynitrite (PRN). We tested a set of strains, all susceptible to AMR and CPX, and these antifungals significantly reduced T. interdigitale viability within 24 h. This effect occurred concomitantly with reduced ergosterol, increased production of ROS and PRN, and consequently increased lipid peroxidation. Together, these mechanisms lead to cell damage and fungal death. These fungicidal effects were abolished when PRN and superoxide scavengers were used in the assays, demonstrating the role of these species in the mechanism of action. We also studied the antioxidant system when T. interdigitale was exposed to AMR and CPX. Interestingly, superoxide dismutase and catalase inhibition lead to altered ROS and PRN production, lipid peroxidation, and ergosterol levels. In fact, the combination of AMR or CPX with a superoxide dismutase inhibitor was antagonistic. Together, these data demonstrate the importance of ROS and PRN in the antifungal action of AMR and CPX against the evaluated T. interdigitale strains. LAY SUMMARY: Onychomycosis is a nail infection, which can be treated with amorolfine and ciclopirox olamine. Here we demonstrate that these drugs exhibit antifungal activity also through the production of oxidative and nitrosative radicals.


Assuntos
Arthrodermataceae , Onicomicose , Animais , Antifúngicos/uso terapêutico , Ciclopirox/farmacologia , Ciclopirox/uso terapêutico , Ergosterol , Testes de Sensibilidade Microbiana/veterinária , Morfolinas , Nitrogênio , Onicomicose/microbiologia , Onicomicose/veterinária , Oxigênio , Espécies Reativas de Oxigênio , Superóxido Dismutase , Trichophyton
15.
Front Immunol ; 13: 933137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874695

RESUMO

Animals adjust their lipid metabolism states in response to pathogens infection. However, the underlying molecular mechanisms for how lipid metabolism responds to infection remain to be elusive. In this study, we assessed the temporal changes of lipid metabolism profiles during infection by an integrated transcriptomics and lipidomics analysis. Ergosterol is identified to be required for proper host defense to pathogens. Notably, ergosterol level is increased in the hemolymph upon bacterial infection. We show that the increase of ergosterol level by food supplement or genetic depletion of Acsl, a long-chain fatty acid-CoA synthetase, promotes host survival against bacterial challenges. Together, our results suggest a critical role of lipid metabolism adaption in the process of host defense against invading pathogens.


Assuntos
Infecções Bacterianas , Lipidômica , Animais , Drosophila , Ergosterol , Transcriptoma
16.
Molecules ; 27(13)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35807334

RESUMO

Trypanosoma brucei, the causative agent for human African trypanosomiasis, is an emerging ergosterol-dependent parasite that produces chokepoint enzymes, sterol methyltransferases (SMT), not synthesized in their animal hosts that can regulate cell viability. Here, we report the lethal effects of two recently described natural product antimetabolites that disrupt Acanthamoeba sterol methylation and growth, cholesta-5,7,22,24-tetraenol (CHT) and ergosta-5,7,22,24(28)-tetraenol (ERGT) that can equally target T. brucei. We found that CHT/ERGT inhibited cell growth in vitro, yielding EC50 values in the low nanomolar range with washout experiments showing cidal activity against the bloodstream form, consistent with their predicted mode of suicide inhibition on SMT activity and ergosterol production. Antimetabolite treatment generated altered T. brucei cell morphology and death rapidly within hours. Notably, in vivo ERGT/CHT protected mice infected with T. brucei, doubling their survival time following daily treatment for 8-10 days at 50 mg/kg or 100 mg/kg. The current study demonstrates a new class of lead antibiotics, in the form of common fungal sterols, for antitrypanosomal drug development.


Assuntos
Trypanosoma brucei brucei , Tripanossomíase Africana , Animais , Antimetabólitos/metabolismo , Antimetabólitos/farmacologia , Ergosterol , Humanos , Camundongos , Esteroides/farmacologia , Esteróis/metabolismo , Esteróis/farmacologia , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/prevenção & controle
17.
Biomed Res Int ; 2022: 6230193, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782069

RESUMO

Isoflavaspidic acid PB (PB), a phloroglucinol derivative extracted from aerial parts of Dryopteris fragrans (L.) Schott, had antifungal activity against several dermatophytes. This study was aimed at exploring the antifungal mechanism of PB against Trichophyton rubrum (T. rubrum). The effectiveness of PB in inhibiting T. rubrum growth was detected by time-kill kinetics study and fungal biomass determination. Studies on the mechanism of action were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), sorbitol and ergosterol assay, nucleotide leakage measurement, and UPLC-based test and enzyme-linked immunosorbent assay. Fungicidal activity of PB was concentration- and time-dependent at 2 × MIC (MIC: 20 µg/mL) after 36 h. The total biomass of T. rubrum was reduced by 64.17%, 77.65%, and 84.71% in the presence of PB at 0.5 × MIC, 1 × MIC, and 2 × MIC, respectively. SEM analysis showed that PB changed mycelial morphology, such as shrinking, twisting, collapsing, and even flattening. TEM images of treated cells exhibited abnormal distributions of polysaccharide particles, plasmolysis, and cytoplasmic content degradation accompanied by plasmalemma disruption. There were no changes in the MIC of PB in the presence of sorbitol. However, the MIC values of PB were increased by 4-fold with exogenous ergosterol. At 4 h and 8 h, PB increased nucleotide leakage. Besides, ergosterol content in T. rubrum membrane treated with PB at 0.5 × MIC, 1 × MIC, and 2 × MIC was decreased by 9.58%, 15.31%, and 76.24%, respectively. There was a dose-dependent decrease in the squalene epoxidase (SE) activity. And the reduction in the sterol 14α-demethylase P450 (CYP51) activity was achieved after PB treatments at 1 × MIC and 2 × MIC. These results suggest that PB displays nonspecific action on the cell wall. The membrane damaging effects of PB were attributed to binding with ergosterol to increase membrane permeability and interfering ergosterol biosynthesis involved with the reduction of SE and CYP51 activities. Further study is needed to develop PB as a natural antifungal candidate for clinical use.


Assuntos
Arthrodermataceae , Dryopteris , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Ergosterol/farmacologia , Testes de Sensibilidade Microbiana , Nucleotídeos/metabolismo , Permeabilidade , Sorbitol/metabolismo , Sorbitol/farmacologia , Trichophyton/metabolismo
18.
Life Sci ; 305: 120779, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35798070

RESUMO

AIM: The present study aimed to prepare a novel lipophilic fraction rich in fat soluble bioactive from Agaricus bisporus and investigated its impact through in vitro and in vivo assessments since the prospective biological activities of fat soluble components from mushrooms are limited. METHODS: Ergosterol concentrate fraction (ECF) preparation followed by subsequent characterization of the extract using various analytical techniques (HPLC-UV, Mass spectroscopy, NMR). Furthermore, the fraction has been evaluated for antioxidant activity, DNA protection ability, hypolipidemic properties by in vitro specific enzyme inhibition and in vivo animal model (C57BL/6). KEY FINDINGS: The fraction majorly contains ergosterol (504 mg/100 g dw) and linoleic acid (71.92 %). In vitro studies showed that the fraction limited free radicals induced DNA damage, exhibited significant free radical scavenging activities (IC50 of DPPH 15.64; ABTS 8.28 mg/ml), and inhibited HMG-CoA reductase activity (IC50 5.03 mg/ml). Further, in vivo study showed that ECF treatment significantly (p < 0.05) improved insulin sensitivity (reduced plasma glucose & insulin, increased adiponectin) and reduced inflammatory markers (CRP & TNF-α) in comparison to high fat fed mice. Furthermore, ECF has significantly reduced plasma lipid profile and accumulation of lipids in liver. This could be due to down regulation of mRNA expression of lipogenic transcription factors such as SREBP-1c and SREBP-2, and key lipogenic enzyme ACC. Moreover, ECF treatment has suppressed protein expression of FAS, induced cholesterol clearance by enhancing LDL-R protein expression. SIGNIFICANCE: The present work for the first time evaluated the synergistic potential of ergosterol and linoleic acid to improve antioxidant defense system and ameliorate obesity associated metabolic dysfunction.


Assuntos
Ácido Linoleico , Obesidade , Agaricus , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Ergosterol/química , Ergosterol/metabolismo , Ergosterol/farmacologia , Ácido Linoleico/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Estudos Prospectivos
19.
Appl Microbiol Biotechnol ; 106(13-16): 4995-5006, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35819513

RESUMO

The influences of three wheat gluten peptides (WGP-LL, WGP-LML, and WGP-LLL) on the osmotic stress tolerance and membrane lipid component in brewer's yeast were investigated. The results demonstrated that the growth and survival of yeast under osmotic stress were enhanced by WGP supplementation. The addition of WGP upregulated the expressions of OLE1 (encoded the delta-9 fatty acid desaturase) and ERG1 (encoded squalene epoxidase) genes under osmotic stress. At the same time, WGP addition enhanced palmitoleic acid (C16:1) content, unsaturated fatty acids/saturated fatty acids ratio, and the amount of ergosterol in yeast cells under osmotic stress. Furthermore, yeast cells in WGP-LL and WGP-LLL groups were more resistant to osmotic stress. WGP-LL and WGP-LLL addition caused 25.08% and 27.02% increase in membrane fluidity, 22.36% and 29.54% reduction in membrane permeability, 18.38% and 14.26% rise in membrane integrity in yeast cells, respectively. In addition, scanning electron microscopy analysis revealed that the addition of WGP was capable of maintaining yeast cell morphology and reducing cell membrane damage under osmotic stress. Thus, alteration of membrane lipid component by WGP was an effective approach for increasing the growth and survival of yeast cells under osmotic stress. KEY POINTS: •WGP addition enhanced cell growth and survival of yeast under osmotic stress. •WGP addition increased unsaturated fatty acids and ergosterol contents in yeast. •WGP supplementation improved membrane homeostasis in yeast at osmotic stress.


Assuntos
Saccharomyces cerevisiae , Triticum , Ergosterol/metabolismo , Ácidos Graxos Insaturados/metabolismo , Glutens/metabolismo , Lipídeos de Membrana/metabolismo , Pressão Osmótica , Peptídeos/metabolismo , Saccharomyces cerevisiae/metabolismo , Triticum/metabolismo
20.
Zhongguo Zhong Yao Za Zhi ; 47(10): 2614-2622, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35718479

RESUMO

In this study, we used bioinformatic tools to analyze the 3-hydroxy-3-methylglutaryl-CoA reductase(HMGR) genes from Glycyrrhiza uralensis, Artemisia annua, and Arabidopsis thaliana. The results indicated that GuHMGR and AaHMGR contained two transmembrane regions while AtHMGR had three transmembrane regions. GuHMGR, AaHMGR, and AtHMGR all had the active center for catalysis. Three truncated HMGR genes(tHMGRs) of G. uralensi, A. annua, and A. thaliana were respectively ligated to pYES3 vector to construct the recombinant plasmids pYES3-tGuHMGR,pYES3-tAaHMGR,and pYES3-tAtHMGR. Afterwards, the control plasmid pYES3 and the three plasmids and were respectively introduced into Saccharomyces cerevisiae Cen.pk2-1 D, which yielded strains Y0, Y1, Y2, and Y3, respectively. The content of squalene, lanosterol, and ergosterol in these strains was measured by GC-MS. The relative expression of tGuHMGR, tAaHMGR, and tAtHMGR in strains Y1, Y2, and Y3 was determined by quantitative real-time PCR. The results showed that the strain overexpressing tAaHMGR had the highest yield of squalene and the highest total yield of squalene, ergosterol, and lanosterol. The quantitative real-time PCR showed higher relative expression of tAaHMGR than tGuHMGR, consistent with the strain fermentation result. We selected a superior tHMGR by comparing the effects of different tHMGRs on the mevalonate(MVA) pathway flux in S. cerevisiae. The findings can provide a reference for the construction of S. cerevisiae strains with high yields of squalene and terpenoid precursors.


Assuntos
Ácido Mevalônico , Saccharomyces cerevisiae , Ergosterol , Lanosterol , Ácido Mevalônico/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Esqualeno/metabolismo
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