scholarly journals Assessing the bioactive profile of anti-fungal loaded calcium sulfate against fungal biofilms

2021 ◽  
Author(s):  
Mark C. Butcher ◽  
Jason L. Brown ◽  
Donald Hansom ◽  
Rebecca Wilson-van Os ◽  
Craig Delury ◽  
...  
Keyword(s):  
Calcium Sulfate ◽  
Fungal Pathogens ◽  
Pathogenic Fungi ◽  
Fungal Species ◽  
Antifungal Drugs ◽  
Release Mechanism ◽  
Local Antibiotics ◽  
Biofilm Inhibition

Calcium sulfate (CS) has been used clinically as a bone or void filling biomaterial, and due to its resorptive properties have provided the prospect for its use as a release mechanism for local antibiotics to control biofilms. Here, we aimed to test CS beads loaded with three antifungal drugs against planktonic and sessile fungal species to assess whether these antifungal beads could be harnessed to provide consistent release of antifungals at biofilm inhibitive doses. A panel of different fungal species (n=15) were selected for planktonic broth microdilution testing with fluconazole (FLZ), amphotericin B (AMB) and caspofungin (CSP). After establishing planktonic inhibition, antifungal CS beads were introduced to fungal biofilms (n=5) to assess biofilm formation and cell viability through a combination of standard quantitative and qualitative biofilm assays. Inoculation of a hydrogel substrate, packed with antifungal CS beads, was also used to assess diffusion through a semi-dry material, to mimic active infection in-vivo. In general, antifungals released from CS loaded beads were all effective at inhibiting the pathogenic fungi over 7-days within standard MIC ranges for these fungi. We observed a significant reduction of pre-grown fungal biofilms across key fungal pathogens following treatment, with visually observable changes in cell morphology and biofilm coverage provided by scanning electron microscopy. Assessment of biofilm inhibition also revealed reductions in total and viable cells across all organisms tested. These data show that antifungal loaded CS beads produce a sustained antimicrobial effect, which inhibits and kills clinically relevant fungal species in-vitro as planktonic and biofilm cells.

Virulence and in vitro Characteristics of Pathogenic Fungi Isolated from Soil by Baiting with Coptotermes formosanus (Isoptera: Rhinotermitidae)

2003 ◽  
Vol 38 (3) ◽  
pp. 342-358 ◽  
Author(s):  
Jianzhong Sun ◽  
James R. Fuxa ◽  
Gregg Henderson
Keyword(s):  
Pathogenic Fungi ◽  
Fungal Species ◽  
Coptotermes Formosanus ◽  
Survival Times ◽  
Fungal Virulence ◽  
Fungal Isolates ◽  
Sampling Locations ◽  
Lethal Doses

Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) was used as “bait” to isolate pathogenic fungi from soil. Ninety soil samples were collected from woodlands and pastures in the vicinities of Baton Rouge, New Orleans, and Lake Charles, LA, from which six Metarhizium anisopliae (Metsch.) Sorokin and nine Beauveria bassiana (Balsamo) Vuillemin isolates were obtained. Numbers of fungal isolates from the three sampling locations did not differ, but more isolates were found in woodlands than in pastures. Median lethal doses (LD50s) of these fungal species to C. formosanus were interspersed, indicating that fungal isolates rather than species had the greatest effect on virulence. Among nine Louisiana and two USDA isolates of B. bassiana, LD50s ranged from 4.95 × 103 to 4.96 × 105 conidia/termite, a difference of 100×. LD50s of six Louisiana and four USDA isolates of M. anisopliae ranged from 7.89 × 103 to 1.22 × 105 conidia/termite. Survival time also was used to compare virulence; M. anisopliae infections caused significantly shorter host survival times than B. bassiana. In vitro growth characteristics were significantly correlated with virulence against termites, suggesting that the characteristics of a fungus growing on agar might contribute to estimating the fungal virulence in vivo.

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 A marine microbiome antifungal targets urgent-threat drug-resistant fungi

Science ◽  
2020 ◽  
Vol 370 (6519) ◽  
pp. 974-978 ◽  
Author(s):  
Fan Zhang ◽  
Miao Zhao ◽  
Doug R. Braun ◽  
Spencer S. Ericksen ◽  
Jeff S. Piotrowski ◽  
...  
Keyword(s):  
Mode Of Action ◽  
Fungal Pathogens ◽  
Antifungal Drugs ◽  
Multiple Drug ◽  
Drug Resistant ◽  
Candida Auris ◽  
Marine Animals ◽  
Multiple Drug Resistant

New antifungal drugs are urgently needed to address the emergence and transcontinental spread of fungal infectious diseases, such as pandrug-resistant Candida auris. Leveraging the microbiomes of marine animals and cutting-edge metabolomics and genomic tools, we identified encouraging lead antifungal molecules with in vivo efficacy. The most promising lead, turbinmicin, displays potent in vitro and mouse-model efficacy toward multiple-drug–resistant fungal pathogens, exhibits a wide safety index, and functions through a fungal-specific mode of action, targeting Sec14 of the vesicular trafficking pathway. The efficacy, safety, and mode of action distinct from other antifungal drugs make turbinmicin a highly promising antifungal drug lead to help address devastating global fungal pathogens such as C. auris.

scholarly journals DC-SIGN targets amphotericin B-loaded liposomes to diverse pathogenic fungi

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Suresh Ambati ◽  
Tuyetnhu Pham ◽  
Zachary A. Lewis ◽  
Xiaorong Lin ◽  
Richard B. Meagher
Keyword(s):  
Amphotericin B ◽  
Fungal Infections ◽  
Pathogenic Fungi ◽  
Antifungal Drugs ◽  
Protein Isoforms ◽  
Viral Pathogens ◽  
Life Threatening ◽  
Better Than

Abstract Background Life-threatening invasive fungal infections are treated with antifungal drugs such as Amphotericin B (AmB) loaded liposomes. Our goal herein was to show that targeting liposomal AmB to fungal cells with the C-type lectin pathogen recognition receptor DC-SIGN improves antifungal activity. DC-SIGN binds variously crosslinked mannose-rich and fucosylated glycans and lipomannans that are expressed by helminth, protist, fungal, bacterial and viral pathogens including three of the most life-threatening fungi, Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans. Ligand recognition by human DC-SIGN is provided by a carbohydrate recognition domain (CRD) linked to the membrane transit and signaling sequences. Different combinations of the eight neck repeats (NR1 to NR8) expressed in different protein isoforms may alter the orientation of the CRD to enhance its binding to different glycans. Results We prepared two recombinant isoforms combining the CRD with NR1 and NR2 in isoform DCS12 and with NR7 and NR8 in isoform DCS78 and coupled them to a lipid carrier. These constructs were inserted into the membrane of pegylated AmB loaded liposomes AmB-LLs to produce DCS12-AmB-LLs and DCS78-AmB-LLs. Relative to AmB-LLs and Bovine Serum Albumin coated BSA-AmB-LLs, DCS12-AmB-LLs and DCS78-AmB-LLs bound more efficiently to the exopolysaccharide matrices produced by A. fumigatus, C. albicans and C. neoformans in vitro, with DCS12-AmB-LLs performing better than DCS78-AmB-LLs. DCS12-AmB-LLs inhibited and/or killed all three species in vitro significantly better than AmB-LLs or BSA-AmB-LLs. In mouse models of invasive candidiasis and pulmonary aspergillosis, one low dose of DCS12-AmB-LLs significantly reduced the fungal burden in the kidneys and lungs, respectively, several-fold relative to AmB-LLs. Conclusions DC-SIGN’s CRD specifically targeted antifungal liposomes to three highly evolutionarily diverse pathogenic fungi and enhanced the antifungal efficacy of liposomal AmB both in vitro and in vivo. Targeting significantly reduced the effective dose of antifungal drug, which may reduce drug toxicity, be effective in overcoming dose dependent drug resistance, and more effectively kill persister cells. In addition to fungi, DC-SIGN targeting of liposomal packaged anti-infectives have the potential to alter treatment paradigms for a wide variety of pathogens from different kingdoms including protozoans, helminths, bacteria, and viruses which express its cognate ligands.

scholarly journals From Design to in Vivo Active Organometallic-Containing Antimycotic Agents

2020 ◽  
Author(s):  
Riccardo Rubbiani ◽  
Tobias Weil ◽  
Noemi Tocci ◽  
Luciano Mastrobuoni ◽  
Severin Jeger ◽  
...  
Keyword(s):  
Rational Design ◽  
Fungal Infections ◽  
Binding Mode ◽  
Fungal Species ◽  
Antifungal Drugs ◽  
Hospital Environment ◽  
Ros Generation ◽  
Mice Model

Fungal infections are an alarming global problem, most importantly for immunocompromised patients in a hospital environment. The appearance of multidrug resistance in several fungal species is a strong indication that alternative treatments are required. Azoles represent the mainstay of antifungal drugs, and their mode of action involves the binding mode of these molecules to the fungal lanosterol 14α-demethylase target enzyme. In this work, by rational design, we have prepared and characterized four novel organometallic derivatives of the frontline antifungal drug fluconazole (<b>1a-4a</b>). All compounds showed excellent <i>in vitro</i> activity against the yeast <i>C. robusta</i>, clearly surpassing the progenitor organic drug fluconazole. As anticipated, due to the presence of the ferrocenyl moiety in <b>1a-4a</b>, a modest increase in ROS generation was observed on <i>C. robusta</i> upon treatment. Very importantly, enzyme inhibition and chemogenetic profiling demonstrated that lanosterol 14α-demethylase was the main target of the most active compound of the series, (<i>N</i>-(ferrocenylmethyl)-2-(2,4-difluorophenyl)-2-hydroxy-N-methyl-3-(1H-1,2,4-triazol-1-yl)propan-1-aminium chloride, <b>2a</b>). Transmission electron microscopy (TEM) studies suggested that <b>2a</b> induced a loss in wall integrity as well as intracellular features ascribable to late apoptosis or necrosis. The impressive activity of <b>2a</b> was further confirmed on clinical isolates, where antimycotic potency up to 400 times higher than fluconazole was observed. Also, <b>2a </b>showed activity towards azole-resistant strains. This finding is very interesting since the target of <b>2a</b> is primarily the same as that of fluconazole, emphasizing the role played by the organometallic moiety. <i>In vivo</i> experiments conducted with <b>2a</b> at a dose of 10 mg/Kg in mice model of <i>Candida</i> infections, while not decreasing fungal burden in the kidney, reduced distal distribution to liver and brain and greatly improved the inflammatory pathology in the kidney and colon, compared to untreated mice.<br>

scholarly journals From Design to in Vivo Active Organometallic-Containing Antimycotic Agents

2020 ◽  
Author(s):  
Riccardo Rubbiani ◽  
Tobias Weil ◽  
Noemi Tocci ◽  
Luciano Mastrobuoni ◽  
Severin Jeger ◽  
...  
Keyword(s):  
Rational Design ◽  
Fungal Infections ◽  
Binding Mode ◽  
Fungal Species ◽  
Antifungal Drugs ◽  
Hospital Environment ◽  
Ros Generation ◽  
Mice Model

Fungal infections are an alarming global problem, most importantly for immunocompromised patients in a hospital environment. The appearance of multidrug resistance in several fungal species is a strong indication that alternative treatments are required. Azoles represent the mainstay of antifungal drugs, and their mode of action involves the binding mode of these molecules to the fungal lanosterol 14α-demethylase target enzyme. In this work, by rational design, we have prepared and characterized four novel organometallic derivatives of the frontline antifungal drug fluconazole (<b>1a-4a</b>). All compounds showed excellent <i>in vitro</i> activity against the yeast <i>C. robusta</i>, clearly surpassing the progenitor organic drug fluconazole. As anticipated, due to the presence of the ferrocenyl moiety in <b>1a-4a</b>, a modest increase in ROS generation was observed on <i>C. robusta</i> upon treatment. Very importantly, enzyme inhibition and chemogenetic profiling demonstrated that lanosterol 14α-demethylase was the main target of the most active compound of the series, (<i>N</i>-(ferrocenylmethyl)-2-(2,4-difluorophenyl)-2-hydroxy-N-methyl-3-(1H-1,2,4-triazol-1-yl)propan-1-aminium chloride, <b>2a</b>). Transmission electron microscopy (TEM) studies suggested that <b>2a</b> induced a loss in wall integrity as well as intracellular features ascribable to late apoptosis or necrosis. The impressive activity of <b>2a</b> was further confirmed on clinical isolates, where antimycotic potency up to 400 times higher than fluconazole was observed. Also, <b>2a </b>showed activity towards azole-resistant strains. This finding is very interesting since the target of <b>2a</b> is primarily the same as that of fluconazole, emphasizing the role played by the organometallic moiety. <i>In vivo</i> experiments conducted with <b>2a</b> at a dose of 10 mg/Kg in mice model of <i>Candida</i> infections, while not decreasing fungal burden in the kidney, reduced distal distribution to liver and brain and greatly improved the inflammatory pathology in the kidney and colon, compared to untreated mice.<br>

scholarly journals The Use of Galleria mellonella Larvae to Identify Novel Antimicrobial Agents against Fungal Species of Medical Interest

2018 ◽  
Vol 4 (3) ◽  
pp. 113 ◽  
Author(s):  
Kevin Kavanagh ◽  
Gerard Sheehan
Keyword(s):  
Fungal Pathogens ◽  
Antimicrobial Agents ◽  
Galleria Mellonella ◽  
Fungal Infections ◽  
Fungal Species ◽  
Molecular Techniques ◽  
Antifungal Drugs ◽  
Immune Priming ◽  
Greater Wax Moth

The immune system of insects and the innate immune response of mammals share many similarities and, as a result, insects may be used to assess the virulence of fungal pathogens and give results similar to those from mammals. Larvae of the greater wax moth Galleria mellonella are widely used in this capacity and also for assessing the toxicity and in vivo efficacy of antifungal drugs. G. mellonella larvae are easy to use, inexpensive to purchase and house, and have none of the legal/ethical restrictions that are associated with use of mammals. Larvae may be inoculated by intra-hemocoel injection or by force-feeding. Larvae can be used to assess the in vivo toxicity of antifungal drugs using a variety of cellular, proteomic, and molecular techniques. Larvae have also been used to identify the optimum combinations of antifungal drugs for use in the treatment of recalcitrant fungal infections in mammals. The introduction of foreign material into the hemocoel of larvae can induce an immune priming effect which may operate independently with the activity of the antifungal drug. Procedures to identify this effect and limit its action are required.

scholarly journals Phenomic profiling of a novel sibling species within the Scedosporium complex in Thailand

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
T. Kitisin ◽  
S. Ampawong ◽  
W. Muangkaew ◽  
P. Sukphopetch
Keyword(s):  
Pathogenic Fungi ◽  
Antifungal Drugs ◽  
Public Park ◽  
In Vivo Models ◽  
Pathological Characteristics ◽  
High Virulence ◽  
A New Species ◽  
Immunocompetent Patients

Abstract Background Scedosporium species are a group of pathogenic fungi, which can be found worldwide around high human-impacted areas. Infections of Scedosporium have been reported in several immunocompromised and immunocompetent patients with a high mortality rate. Recently, we have isolated and identified several Scedosporium strains during an environmental survey in Thailand. Results We describe the isolate, TMMI-012, possibly a new species isolated from soils in the Chatuchak public park, Bangkok, Thailand. TMMI-012 is phylogenetically related to the Scedosporium genus and is a sibling to S. boydii but shows distinct morphological and pathological characteristics. It is fast growing and highly resistant to antifungal drugs and abiotic stresses. Pathological studies of in vitro and in vivo models confirm its high virulence and pathogenicity. Conclusion TMMI-012 is considered a putative novel Scedosporium species. The high antifungal resistance of TMMI-012 compared with its sibling, Scedosporium species is likely related to its clinical impact on human health.

scholarly journals IN VITRO AND IN VIVO ANTIFUNGAL ACTIVITY OF ALKALOID 3,5-bis(4,4’’-dimethoxy- [1,1’:2’,1’’-terphenyl]-4’-yl)-4H-pyrazole-4,4-diol FROM DERRIS INDICA (LAM) BENNETT SEEDS

2021 ◽  
pp. 133-140
Author(s):  
NUZHAT TABASSUM ◽  
VIDYASAGAR G. M. ◽  
RAGHUNANDAN D ◽  
SHIVAKUMAR I
Keyword(s):  
Antifungal Activity ◽  
Fungal Pathogens ◽  
Antifungal Drugs ◽  
Hexane Extract ◽  
In Vivo Studies ◽  
Antifungal Compound ◽  
In Vivo Evaluation ◽  
Derris Indica

Objectives: The aim of the present study is to isolate an antifungal compound from Derris indica (Lam) Bennett seed oil with various solvents and evaluation of its antifungal activity against the clinical species of Candida. Methods: D. indica seed hexane extract was tested against Trichophyton rubrum, Trichophyton tonsurans and Candida albicans. Hexane extract was fractioned using different solvents through column chromatography (CC). Isolated compound D1 was identified and characterized using ultraviolet, Fourier-transform infrared, 1HNMR, and mass spectroscopy. In vitro evaluation of D1 carried out against 12 Candida strains. In vivo evaluation of D1 carried out against T. rubrum, T. tonsurans, and C. albicans using an excision wound healing model on male Wistar rats. Results: Different concentrations of hexane extract showed antimicrobial activity against tested microorganism with varying minimum inhibitory concentration values. On fractionation with hexane-petroleum ether through CC, it yielded a crystalline fraction. Compound D1 characterized as a 3,5-bis (4,4’’-dimethoxy-[1,1’: 2’,1’’-terphenyl]-4’-yl)-4H-pyrazole-4,4-diol. A novel alkaloid compound from D. indica is a new report and proved to be inhibitory against C. albicans MTCC 3017 (14.83±0.28), MTCC 1637 (16.0±0.0), Candida glabrata MTCC 3814 (16.83±0.28) and MTCC 3014 (16.66±0.57), Candida tropicalis MTCC 230 (20.0±0.0), MTCC 1406 (12.33±0.57). C. glabrata MTCC 3981 was found to be resistant to the compound. In vivo studies showed no visual symptoms at the end of treatment indicating the therapeutic property of the compound. Conclusion: The D1 was found to be effective against human fungal pathogens and can be used as a base molecule in designing new antifungal drugs.

scholarly journals A Nanoemulsion as an Effective Treatment Against Human Pathogenic Fungi

2019 ◽  
Author(s):  
Alexis Garcia ◽  
Yong Yi Fan ◽  
Sandeep Vellanki ◽  
Eun Young Huh ◽  
DiFernando Vanegas ◽  
...  
Keyword(s):  
Fungal Pathogens ◽  
Fungal Infections ◽  
Healing Process ◽  
Pathogenic Fungi ◽  
Multidrug Resistant ◽  
Antifungal Drugs ◽  
Therapeutic Approaches ◽  
New Therapeutic Approaches ◽  
Development Of Resistance

AbstractThe emergence of immunocompromising diseases such as HIV/AIDS or other immunosuppressive medical conditions have opened an opportunity for fungal infections to afflict patients globally. An increase antifungal drug resistant fungi have posed a serious threat to patients. Combining these circumstances with a limited variety of antifungal drugs available to treat patients has left us in a situation where we need to develop new therapeutic approaches that are less prone to development of resistance by pathogenic fungi. In this study we present the utilization of the nanoemulsion NB-201 to control human pathogenic fungi. We found that the NB-201 exhibited in vitro activity against C. albicans, including both planktonic growth and biofilms. Furthermore, treatments with NB-201 significantly reduced the fungal burden at the infection site and presented enhanced healing process after subcutaneous infections by multidrug resistant C. albicans in a murine host system. NB-201 also exhibited in vitro growth inhibition activity against other fungal pathogens, including Cryptococcus spp, Aspergillus fumigatus, and Mucorales. Due to the nature of the activity of this nanoemulsion, there is a minimized chance of drug resistance to develop, thus presents a novel treatment to control fungal wound or skin infections.

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