scholarly journals Antifungal effect of all-trans retinoic acid against Aspergillus fumigatus in vitro and in a pulmonary aspergillosis in vivo model

2020 ◽  
Author(s):  
Elena Campione ◽  
Roberta Gaziano ◽  
Elena Doldo ◽  
Daniele Marino ◽  
Mattia Falconi ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Aspergillus Fumigatus ◽  
Rat Model ◽  
Fungal Infections ◽  
Invasive Pulmonary Aspergillosis ◽  
Antifungal Drugs ◽  
Pulmonary Aspergillosis ◽  
Fungistatic Activity

AIM: Aspergillus fumigatus is the most common opportunistic fungal pathogen and causes invasive pulmonary aspergillosis (IPA), with high mortality among immunosuppressed patients. Fungistatic activity of all-trans retinoic acid (ATRA) has been recently described in vitro. We evaluated the efficacy of ATRA in vivo and its potential synergistic interaction with other antifungal drugs. MATERIALS AND METHODS: A rat model of IPA and in vitro experiments were performed to assess the efficacy of ATRA against Aspergillus in association with classical antifungal drugs and in silico studies used to clarify its mechanism of action. RESULTS: ATRA (0.5 and 1 mM) displayed a strong fungistatic activity in Aspergillus cultures, while at lower concentrations, synergistically potentiated fungistatic efficacy of sub-inhibitory concentration of Amphotericin B (AmB) and Posaconazole (POS). ATRA also enhanced macrophagic phagocytosis of conidia. In a rat model of IPA, ATRA reduced mortality similarly to Posaconazole. CONCLUSION: Fungistatic efficacy of ATRA alone and synergistically with other antifungal drugs was documented in vitro, likely by inhibiting fungal Hsp90 expression and Hsp90-related genes. ATRA reduced mortality in a model of IPA in vivo. Those findings suggest ATRA as suitable fungistatic agent, also to reduce dosage and adverse reaction of classical antifungal drugs, and new therapeutic strategies against IPA and systemic fungal infections.

ADAMTS13 Regulates Neutrophil Recruitment in a Mouse Model of Invasive Pulmonary Aspergillosis

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4109-4109
Author(s):  
Markus Radsak ◽  
Steve Prüfer ◽  
Katharina Ebner ◽  
Michael Weber ◽  
Sebastian Reuter ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Mouse Model ◽  
Aspergillus Fumigatus ◽  
Fungal Infections ◽  
Invasive Pulmonary Aspergillosis ◽  
Polymorphonuclear Neutrophils ◽  
Formyl Peptide Receptor ◽  
Wild Type ◽  
Pulmonary Aspergillosis

Abstract Von Willebrand factor (VWF) is secreted as an acute phase protein during inflammation. The main mechanism regulating the size and prothrombotic activity of VWF is the specific proteolytic activity of ADAMTS-13. To determine the relevance of this regulatory pathway for the innate inflammatory response by polymorphonuclear neutrophils (PMN), we employed a mouse model of invasive pulmonary aspergillosis (IPA) where PMN functionality is crucial for fungal clearance and survival. IPA was induced by intratracheal application of Aspergillus fumigatus conidia in wild-type (129/Sv/Pas) or Adamts13 deficient (Adamts13-/-) mice. After PMN depletion using a anti-Gr-1 specific antibody, all mice infected with Aspergillus fumigatus conidia developed neutropenia and succumbed due to lethal IPA. In contrast, all undepleted wild-type mice survived the infection. Interestingly, Aspergillus fumigatus infection in Adamts13-/- mice was lethal in 20% of the animals displaying a more severe course of IPA, as indicated by an increased fungal burden in lung homogenates along with increased levels of albumin and the inflammatory mediators IL-1β, IL-6, TNF-α, KC and MCP-1 in the bronchio-alveolar lavage fluid (BALF) compared to wild-type controls. Beyond this, we observed a decreased number of PMN in BALF of infected Adamts13-/- mice compared to wild-type mice. Lung histology sections demonstrated a more pronounced perivascular leukocyte infiltration in further support of a dysregulated inflammatory response in Adamts13-/- mice. Importantly, we observed no general defect in the activation of neutrophil effector functions as demonstrated by the normal induction of the oxidative burst, phagocytosis, degranulation, L-selectin shedding and apoptosis in response to formyl-peptide receptor agonists or exposure to Aspergillus fumigatus conidia or hyphae in vitro. Therefore, we conclude that the proteolytic regulation of VWF by ADAMTS-13 in an important mechanism to control PMN recruitment in the regulation of the innate inflammatory response in invasive fungal infections. Disclosures Radsak: Celgene: Research Funding.

In vitro and in vivo characterization of two nonsporulating Aspergillus fumigatus clinical isolates from immunocompetent patients

2019 ◽  
Vol 58 (4) ◽  
pp. 543-551
Author(s):  
Zheng Zhang ◽  
Yuan Jiang ◽  
Jun Chen ◽  
Peiying Chen ◽  
Qingtao Kong ◽  
...  
Keyword(s):  
Invasive Aspergillosis ◽  
Aspergillus Fumigatus ◽  
Pathogenic Fungus ◽  
Antifungal Drugs ◽  
Causative Role ◽  
Immunocompromised Patients ◽  
Pulmonary Aspergillosis ◽  
Brla Gene

Abstract Aspergillus fumigatus is a pathogenic fungus responsible for invasive aspergillosis (IA). Typically, it can produce abundant conidia to survive and spread. The infection by A. fumigatus usually occurs in immunocompromised patients due to failed clearance of inhaled conidia. However, the incidence of aspergillosis in immunocompetent hosts has been increasing, the pathogenesis of which is still unknown. Our team previously obtained two clinical nonsporulating A. fumigatus isolates from non-immunocompromised patients, which only have the form of hyphae. This present study demonstrated the in vitro and in vivo characteristics of the two nonsporulating A. fumigatus isolates and verified that their conidiation defects are associated to abolished expression of the sporulation-related central regulatory pathway brlA gene. In addition, we confirmed the mutation site of brlA gene (c.657_660delTCCT) contributes to the nonsporulating phenotype in one clinical isolate. Plate assay showed that the two nonsporulating isolates have a similar resistance to antifungal drugs, cell wall disturbing substances, and oxidative stress compared with the wild-type reference Af293. Most important of all, we employed an immunocompetent mouse model to mimic the pathogenesis of pulmonary aspergillosis in non-immunocompromised patients. It revealed that the hyphae of two nonsporulating isolates and Af293 have similar virulence in immunocompetent hosts. Interestingly, the hyphae fragments of Af293 but not conidia are able to induce invasive aspergillosis in immunocompetent mice. In conclusion, our study indicate that the form of hyphae may play a dominant causative role in pulmonary aspergillosis of immunocompetent hosts rather than conidia.

scholarly journals Identification of a New Class of Antifungals Targeting the Synthesis of Fungal Sphingolipids

mBio ◽  
2015 ◽  
Vol 6 (3) ◽  
Author(s):  
Visesato Mor ◽  
Antonella Rella ◽  
Amir M. Farnoud ◽  
Ashutosh Singh ◽  
Mansa Munshi ◽  
...  
Keyword(s):  
Cell Cycle Progression ◽  
Fungal Infections ◽  
Pathogenic Fungi ◽  
Antifungal Drugs ◽  
Sequencing Analysis ◽  
Fungal Cell ◽  
New Class ◽  
Narrow Spectrum

ABSTRACT Recent estimates suggest that >300 million people are afflicted by serious fungal infections worldwide. Current antifungal drugs are static and toxic and/or have a narrow spectrum of activity. Thus, there is an urgent need for the development of new antifungal drugs. The fungal sphingolipid glucosylceramide (GlcCer) is critical in promoting virulence of a variety of human-pathogenic fungi. In this study, we screened a synthetic drug library for compounds that target the synthesis of fungal, but not mammalian, GlcCer and found two compounds [N′-(3-bromo-4-hydroxybenzylidene)-2-methylbenzohydrazide (BHBM) and its derivative, 3-bromo-N′-(3-bromo-4-hydroxybenzylidene) benzohydrazide (D0)] that were highly effective in vitro and in vivo against several pathogenic fungi. BHBM and D0 were well tolerated in animals and are highly synergistic or additive to current antifungals. BHBM and D0 significantly affected fungal cell morphology and resulted in the accumulation of intracellular vesicles. Deep-sequencing analysis of drug-resistant mutants revealed that four protein products, encoded by genes APL5, COS111, MKK1, and STE2, which are involved in vesicular transport and cell cycle progression, are targeted by BHBM. IMPORTANCE Fungal infections are a significant cause of morbidity and mortality worldwide. Current antifungal drugs suffer from various drawbacks, including toxicity, drug resistance, and narrow spectrum of activity. In this study, we have demonstrated that pharmaceutical inhibition of fungal glucosylceramide presents a new opportunity to treat cryptococcosis and various other fungal infections. In addition to being effective against pathogenic fungi, the compounds discovered in this study were well tolerated by animals and additive to current antifungals. These findings suggest that these drugs might pave the way for the development of a new class of antifungals.

scholarly journals Combination Therapy in Treatment of Experimental Pulmonary Aspergillosis: In Vitro and In Vivo Correlations of the Concentration- and Dose- Dependent Interactions between Anidulafungin and Voriconazole by Bliss Independence Drug Interaction Analysis

2009 ◽  
Vol 53 (6) ◽  
pp. 2382-2391 ◽  
Author(s):  
Vidmantas Petraitis ◽  
Ruta Petraitiene ◽  
William W. Hope ◽  
Joseph Meletiadis ◽  
Diana Mickiene ◽  
...  
Keyword(s):  
Drug Interaction ◽  
Interaction Analysis ◽  
Invasive Pulmonary Aspergillosis ◽  
Pulmonary Aspergillosis ◽  
Treatment Groups ◽  
Synergistic Interactions ◽  
Significant Difference ◽  
Bliss Independence

ABSTRACT We studied the antifungal activity of anidulafungin (AFG) in combination with voriconazole (VRC) against experimental invasive pulmonary aspergillosis (IPA) in persistently neutropenic rabbits and further explored the in vitro and in vivo correlations by using Bliss independence drug interaction analysis. Treatment groups consisted of those receiving AFG at 5 (AFG5 group) and 10 (AFG10 group) mg/kg of body weight/day, VRC at 10 mg/kg every 8 h (VRC group), AFG5 plus VRC (AFG5+VRC group), and AFG10 plus VRC (AFG10+VRC group) and untreated controls. Survival throughout the study was 60% for the AFG5+VRC group, 50% for the VRC group, 27% for the AFG10+VRC group, 22% for the AFG5 group, 18% for the AFG10 group, and 0% for control rabbits (P < 0.001). There was a significant reduction of organism-mediated pulmonary injury, measured by infarct scores, lung weights, residual fungal burdens, and galactomannan indexes, in AFG5+VRC-treated rabbits versus those treated with AFG5 and VRC alone (P < 0.05). In comparison, AFG10+VRC significantly lowered only infarct scores and lung weights in comparison to those of AFG10-treated animals (P < 0.05). AFG10+VRC showed no significant difference in other outcome variables. Significant Bliss synergy was found in vivo between AFG5 and VRC, with observed effects being 24 to 30% higher than expected levels if the drugs were acting independently. These synergistic interactions were also found between AFG and VRC in vitro. However, for AFG10+VRC, only independence and antagonism were observed among the outcome variables. We concluded that the combination of AFG with VRC in treatment of experimental IPA in persistently neutropenic rabbits was independent to synergistic at a dosage of 5 mg/kg/day but independent to antagonistic at 10 mg/kg/day, as assessed by Bliss independence analysis, suggesting that higher dosages of an echinocandin may be deleterious to the combination.

scholarly journals Aspergillus fumigatus Strain-Specific Conidia Lung Persistence Causes an Allergic Broncho-Pulmonary Aspergillosis-Like Disease Phenotype

mSphere ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jane T. Jones ◽  
Ko-Wei Liu ◽  
Xi Wang ◽  
Caitlin H. Kowalski ◽  
Brandon S. Ross ◽  
...  
Keyword(s):  
Aspergillus Fumigatus ◽  
Allergic Response ◽  
Mouse Lung ◽  
Disease Phenotype ◽  
Pulmonary Aspergillosis ◽  
Mucus Production ◽  
Content Type

ABSTRACT Aspergillus fumigatus is a filamentous fungus which can cause multiple diseases in humans. Allergic broncho-pulmonary aspergillosis (ABPA) is a disease diagnosed primarily in cystic fibrosis patients caused by a severe allergic response often to long-term A. fumigatus colonization in the lungs. Mice develop an allergic response to repeated inhalation of A. fumigatus spores; however, no strains have been identified that can survive long-term in the mouse lung and cause ABPA-like disease. We characterized A. fumigatus strain W72310, which was isolated from the expectorated sputum of an ABPA patient, by whole-genome sequencing and in vitro and in vivo viability assays in comparison to a common reference strain, CEA10. W72310 was resistant to leukocyte-mediated killing and persisted in the mouse lung longer than CEA10, a phenotype that correlated with greater resistance to oxidative stressors, hydrogen peroxide, and menadione, in vitro. In animals both sensitized and challenged with W72310, conidia, but not hyphae, were viable in the lungs for up to 21 days in association with eosinophilic airway inflammation, airway leakage, serum IgE, and mucus production. W72310-sensitized mice that were recall challenged with conidia had increased inflammation, Th1 and Th2 cytokines, and airway leakage compared to controls. Collectively, our studies demonstrate that a unique strain of A. fumigatus resistant to leukocyte killing can persist in the mouse lung in conidial form and elicit features of ABPA-like disease. IMPORTANCE Allergic broncho-pulmonary aspergillosis (ABPA) patients often present with long-term colonization of Aspergillus fumigatus. Current understanding of ABPA pathogenesis has been complicated by a lack of long-term in vivo fungal persistence models. We have identified a clinical isolate of A. fumigatus, W72310, which persists in the murine lung and causes an ABPA-like disease phenotype. Surprisingly, while viable, W72310 showed little to no growth beyond the conidial stage in the lung. This indicates that it is possible that A. fumigatus can cause allergic disease in the lung without any significant hyphal growth. The identification of this strain of A. fumigatus can be used not only to better understand disease pathogenesis of ABPA and potential antifungal treatments but also to identify features of fungal strains that drive long-term fungal persistence in the lung. Consequently, these observations are a step toward helping resolve the long-standing question of when to utilize antifungal therapies in patients with ABPA and fungal allergic-type diseases.

scholarly journals In Vitro and In Vivo Anti-Candida spp. Activity of Plant-Derived Products

Plants ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 494 ◽  
Author(s):  
Reginaldo dos Santos Pedroso ◽  
Brenda Lorena Balbino ◽  
Géssica Andrade ◽  
Maria Cecilia Pereira Sacardo Dias ◽  
Tavane Aparecida Alvarenga ◽  
...  
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Gallic Acid ◽  
Antifungal Drugs ◽  
Citrus Limon ◽  
Cupressus Sempervirens ◽  
Candida Spp ◽  
Fungistatic Activity

Candidiasis therapy, especially for candidiasis caused by Candida non-albicans species, is limited by the relatively reduced number of antifungal drugs and the emergence of antifungal tolerance. This study evaluates the anticandidal activity of 41 plant-derived products against Candida species, in both planktonic and biofilm cells. This study also evaluates the toxicity and the therapeutic action of the most active compounds by using the Caenorhabditis elegans–Candida model. The planktonic cells were cultured with various concentrations of the tested agents. The Cupressus sempervirens, Citrus limon, and Litsea cubeba essential oils as well as gallic acid were the most active anticandidal compounds. Candida cell re-growth after treatment with these agents for 48 h demonstrated that the L. cubeba essential oil and gallic acid displayed fungistatic activity, whereas the C. limon and C. sempervirens essential oils exhibited fungicidal activity. The C. sempervirens essential oil was not toxic and increased the survival of C. elegans worms infected with C. glabrata or C. orthopsilosis. All the plant-derived products assayed at 250 µg/mL affected C. krusei biofilms. The tested plant-derived products proved to be potential therapeutic agents against Candida, especially Candida non-albicans species, and should be considered when developing new anticandidal agents.

scholarly journals Combination Therapy with Ibrexafungerp (Formerly SCY-078), a First-in-Class Triterpenoid Inhibitor of (1→3)-β-D-Glucan Synthesis, and Isavuconazole for Treatment of Experimental Invasive Pulmonary Aspergillosis

2020 ◽  
Vol 64 (6) ◽  
Author(s):  
Vidmantas Petraitis ◽  
Ruta Petraitiene ◽  
Aspasia Katragkou ◽  
Bo Bo Win Maung ◽  
Ethan Naing ◽  
...  
Keyword(s):  
Invasive Pulmonary Aspergillosis ◽  
Rabbit Model ◽  
Prolonged Survival ◽  
Pulmonary Aspergillosis ◽  
Fungal Burden ◽  
Treatment Groups ◽  
Glucan Synthesis ◽  
Synthase Inhibitor

ABSTRACT Ibrexafungerp (formerly SCY-078) is a semisynthetic triterpenoid and potent (1→3)-β-d-glucan synthase inhibitor. We investigated the in vitro activity, pharmacokinetics, and in vivo efficacy of ibrexafungerp (SCY) alone and in combination with antimold triazole isavuconazole (ISA) against invasive pulmonary aspergillosis (IPA). The combination of ibrexafungerp and isavuconazole in in vitro studies resulted in additive and synergistic interactions against Aspergillus spp. Plasma concentration-time curves of ibrexafungerp were compatible with linear dose proportional profile. In vivo efficacy was studied in a well-established persistently neutropenic New Zealand White (NZW) rabbit model of experimental IPA. Treatment groups included untreated control (UC) rabbits and rabbits receiving ibrexafungerp at 2.5 (SCY2.5) and 7.5 (SCY7.5) mg/kg of body weight/day, isavuconazole at 40 (ISA40) mg/kg/day, or combinations of SCY2.5+ISA40 and SCY7.5+ISA40. The combination of SCY+ISA produced an in vitro synergistic interaction. There were significant in vivo reductions of residual fungal burden, lung weights, and pulmonary infarct scores in SCY2.5+ISA40, SCY7.5+ISA40, and ISA40 treatment groups versus those of the SCY2.5-treated, SCY7.5-treated, and UC (P < 0.01) groups. Rabbits treated with SCY2.5+ISA40 and SCY7.5+ISA40 had prolonged survival in comparison to that of the SCY2.5-, SCY7.5-, ISA40-treated, or UC (P < 0.05) groups. Serum galactomannan index (GMI) and (1→3)-β-d-glucan levels significantly declined in animals treated with the combination of SCY7.5+ISA40 in comparison to those of animals treated with SCY7.5 or ISA40 (P < 0.05). Ibrexafungerp and isavuconazole combination demonstrated prolonged survival, decreased pulmonary injury, reduced residual fungal burden, and lower GMI and (1→3)-β-d-glucan levels in comparison to those of single therapy for treatment of IPA. These findings provide an experimental foundation for clinical evaluation of the combination of ibrexafungerp and an antimold triazole for treatment of IPA.

scholarly journals Ficolins Promote Fungal Clearance in vivo and Modulate the Inflammatory Cytokine Response in Host Defense against Aspergillus fumigatus

2016 ◽  
Vol 8 (6) ◽  
pp. 579-588 ◽  
Author(s):  
Ninette Genster ◽  
Elisabeth Præstekjær Cramer ◽  
Anne Rosbjerg ◽  
Katrine Pilely ◽  
Jack Bernard Cowland ◽  
...  
Keyword(s):  
Aspergillus Fumigatus ◽  
Host Defense ◽  
Knockout Mice ◽  
Fungal Infections ◽  
Inflammatory Cells ◽  
Lectin Pathway ◽  
Wild Type ◽  
Opportunistic Fungal Pathogen

Aspergillus fumigatus is an opportunistic fungal pathogen that causes severe invasive infections in immunocompromised patients. Innate immunity plays a major role in protection against A. fumigatus. The ficolins are a family of soluble pattern recognition receptors that are capable of activating the lectin pathway of complement. Previous in vitro studies reported that ficolins bind to A. fumigatus, but their part in host defense against fungal infections in vivo is unknown. In this study, we used ficolin-deficient mice to investigate the role of ficolins during lung infection with A. fumigatus. Ficolin knockout mice showed significantly higher fungal loads in the lungs 24 h postinfection compared to wild-type mice. The delayed clearance of A. fumigatus in ficolin knockout mice could not be attributed to a compromised recruitment of inflammatory cells. However, it was revealed that ficolin knockout mice exhibited a decreased production of proinflammatory cytokines in the lungs compared to wild-type mice following A. fumigatus infection. The impaired clearance and cytokine production in ficolin knockout mice was independent of complement, as shown by equivalent levels of A. fumigatus-mediated complement activation in ficolin knockout mice and wild-type mice. In conclusion, this study demonstrates that ficolins are important in initial innate host defense against A. fumigatus infections in vivo.

scholarly journals Identification of Essential Genes in the Human Fungal Pathogen Aspergillus fumigatus by Transposon Mutagenesis

2003 ◽  
Vol 2 (2) ◽  
pp. 247-255 ◽  
Author(s):  
Arnaud Firon ◽  
François Villalba ◽  
Roland Beffa ◽  
Christophe d'Enfert
Keyword(s):  
Aspergillus Fumigatus ◽  
Transposable Element ◽  
Drug Targets ◽  
Fungal Infections ◽  
Fungal Growth ◽  
Developed Countries ◽  
Transposon Mutagenesis ◽  
Essential Genes ◽  
Antifungal Drugs

ABSTRACT The opportunistic pathogen Aspergillus fumigatus is the most frequent cause of deadly airborne fungal infections in developed countries. In order to identify novel antifungal-drug targets, we investigated the genome of A. fumigatus for genes that are necessary for efficient fungal growth. An artificial A. fumigatus diploid strain with one copy of an engineered impala160 transposon from Fusarium oxysporum integrated into its genome was used to generate a library of diploid strains by random in vivo transposon mutagenesis. Among 2,386 heterozygous diploid strains screened by parasexual genetics, 1.2% had a copy of the transposable element integrated into a locus essential for A. fumigatus growth. Comparison of genomic sequences flanking impala160 in these mutants with that of the genome of A. fumigatus allowed the characterization of 20 previously uncharacterized A. fumigatus genes. Among these, homologues of genes essential for Saccharomyces cerevisiae growth have been identified, as well as genes that do not have homologues in other fungal species. These results confirm that heterologous transposition using the transposable element impala is a powerful tool for functional genomics in ascomycota, and they pave the way for defining the complete set of essential genes in A. fumigatus, the first step toward target-based development of new antifungal drugs.

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