High Efficiency Drug Repurposing Design for New Antifungal Agents

Current antifungal interventions have often limited efficiency in treating fungal pathogens, particularly those resistant to commercial drugs or fungicides. Antifungal drug repurposing is an alternative intervention strategy, whereby new utility of various marketed, non-antifungal drugs could be repositioned as novel antifungal agents. In this study, we investigated “chemosensitization” as a method to improve the efficiency of antifungal drug repurposing, wherein combined application of a second compound (viz., chemosensitizer) with a conventional, non-antifungal drug could greatly enhance the antifungal activity of the co-applied drug. Redox-active natural compounds or structural derivatives, such as thymol (2-isopropyl-5-methylphenol), 4-isopropyl-3-methylphenol, or 3,5-dimethoxybenzaldehyde, could serve as potent chemosensitizers to enhance antifungal activity of the repurposed drug bithionol. Of note, inclusion of fungal mutants, such as antioxidant mutants, could also facilitate drug repurposing efficiency, which is reflected in the enhancement of antifungal efficacy of bithionol. Bithionol overcame antifungal (viz., fludioxonil) tolerance of the antioxidant mutants of the human/animal pathogen Aspergillus fumigatus. Altogether, our strategy can lead to the development of a high efficiency drug repurposing design, which enhances the susceptibility of pathogens to drugs, reduces time and costs for new antifungal development, and abates drug or fungicide resistance.

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Screening Repurposing Libraries for Identification of Drugs with Novel Antifungal Activity

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00924-20 ◽

2020 ◽

Vol 64 (9) ◽

Cited By ~ 2

Author(s):

Gina Wall ◽

Jose L. Lopez-Ribot

Keyword(s):

Antifungal Activity ◽

Antifungal Agents ◽

Fungal Infections ◽

Alternative Pathway ◽

Drug Repurposing ◽

Pathogenic Fungi ◽

Multidrug Resistant ◽

Modern Medicine ◽

Antifungal Drugs ◽

Promising Alternative

ABSTRACT Fungal organisms are ubiquitous in nature, and progress of modern medicine is creating an expanding number of severely compromised patients susceptible to a variety of opportunistic fungal infections. These infections are difficult to diagnose and treat, leading to high mortality rates. The limited antifungal arsenal, the toxicity of current antifungal drugs, the development of resistance, and the emergence of new multidrug-resistant fungi, all highlight the urgent need for new antifungal agents. Unfortunately, the development of a novel antifungal is a rather long and expensive proposition, and no new classes of antifungal agents have reached the market in the last 2 decades. Drug repurposing, or finding new indications for old drugs, represents a promising alternative pathway to drug development that is particularly appealing within the academic environment. In the last few years, there has been a growing interest in repurposing approaches in the antifungal arena, with multiple groups of investigators having performed screenings of different repurposing libraries against different pathogenic fungi in search for drugs with previously unrecognized antifungal effects. Overall, these repurposing efforts may lead to the fast deployment of drugs with novel antifungal activity, which can rapidly bring benefits to patients, while at the same time reducing health care costs.

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In Vitro Antifungal Activity of Luliconazole, Efinaconazole, and Nine Comparators Against Aspergillus and Candida Strains Isolated from Otomycosis

Jundishapur Journal of Microbiology ◽

10.5812/jjm.115902 ◽

2021 ◽

Vol 14 (4) ◽

Author(s):

Gholamreza Shokoohi ◽

Reza Rouhi ◽

Mohammad Etehadnezhad ◽

Bahram Ahmadi ◽

Javad Javidnia ◽

...

Keyword(s):

Antifungal Activity ◽

Candida Species ◽

Fungal Pathogens ◽

Antifungal Agents ◽

Geometric Mean ◽

Antifungal Drugs ◽

High Recurrence Rate ◽

Broth Microdilution ◽

In Vitro Antifungal Activity

Background: Aspergillus and Candida species are the most commonly identified fungal pathogens in otomycosis. However, we usually encounter some difficulties in its treatment because many patients show resistance to antifungal agents and present a high recurrence rate. Objectives: The current research was conducted to compare the in vitro activities of luliconazole (LUL), and efinaconazole (EFN) and the nine comparators on Aspergillus and Candida strains isolated from otomycosis. Methods: The in vitro activities of nine common antifungal drugs (amphotericin B (AMB), voriconazole (VRC), fluconazole (FLU), itraconazole (ITC), ketoconazole (KTO), clotrimazole (CLO), nystatin (NYS), terbinafine (TRB), and caspofungin (CAS)) and two novel new azoles (LUL and EFN) against of 108 clinical isolates of Aspergillus and Candida species obtained from otomycosis were assessed according to the CLSI broth microdilution document. Results: The LUL and EFN had the geometric mean minimum inhibitory concentrations (GM MICs) of 0.098 and 0.109 μg/mL against all Aspergillus strains, respectively. Furthermore, the GM MICs of all Candida isolates for LUL, EFN, CAS, CLO, VRC, AMB, ITC, KTO, FLU, NYS, and TRB were calculated to be 0.133, 0.144, 0.194, 0.219, 0.475, 0.537, 0.655, 1.277, 4.905, 9.372, and 13.592 μg/mL, respectively. Additionally, 6 (35.29%), 2 (11.7%), and 1 (5.88%) Candida isolates were resistant to FLU, CAS, and VRC, respectively. Conclusions: As the findings indicated, LUL and EFN showed the lowest GM MIC values against the examined species. Accordingly, these novel imidazole and triazole antifungal agents can be regarded as proper candidates for the treatment of otomycosis caused by Aspergillus and Candida strains.

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Drug Repurposing Strategies in the Discovery of Antifungal Agents

10.20944/preprints202102.0405.v1 ◽

2021 ◽

Author(s):

Qian Zhang ◽

Fangyan Liu ◽

Meng Zeng ◽

Caiyan Xin ◽

Jinping Zhang ◽

...

Keyword(s):

Antifungal Activity ◽

Clinical Application ◽

Antifungal Agents ◽

Fungal Infections ◽

Immunosuppressive Agents ◽

Drug Repurposing ◽

Antifungal Drugs ◽

Drug Resistant ◽

Effective Strategies ◽

Prevention And Treatment

The morbidity and mortality caused by invasive fungal infections is increasing across the globe due to developments in transplant surgery, the use of immunosuppressive agents, and the emergence of drug-resistant fungal strains, which has led to a challenge in terms of treatment due to the limitations of three classes of drugs. Hence, it is imperative to establish effective strategies to identify and design new antifungal drugs. Drug repurposing is an effective way of expanding the application of existing drugs. In the last years, various existing drugs have been shown to be useful in the prevention and treatment of the invasive fungi. In this review, we summarize the currently used antifungal agents. In addition, the most up to date information on the effectiveness of existing drugs with antifungal activity is discussed. Moreover, the antifungal mechanisms of existing drugs are highlighted. These data will provide valuable knowledge to stimulate further investigation and clinical application in this field.

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Antifungal activity of rare actinobacterium isolated from forest soil

Research Journal of Biotechnology ◽

10.25303/1610rjbt92101 ◽

2021 ◽

Vol 16 (10) ◽

pp. 92-101

Author(s):

Muralidharan Sasidhar ◽

Selvam Masilamani ◽

Abirami Baskaran ◽

Manigundan Kaari ◽

Radhakrishnan Manikkam

Keyword(s):

Antifungal Activity ◽

Forest Soil ◽

Fungal Pathogens ◽

Antifungal Agents ◽

Carbon Sources ◽

Nitrogen Sources ◽

Antifungal Drugs ◽

Antifungal Compound ◽

Antifungal Compounds ◽

Promising Source

Prolonged use of antifungal drugs has led to the emergence of drug resistant fungal pathogens that pose serious threat to public health and challenge to researchers for discovering novel antifungal agents. Natural products from the members of phylum actinobacteria are the promising source of antibiotics including antifungal agents. Twenty-seven morphologically different actinobacterial cultures were isolated from the forest soils of Sabarimala, Kerala and Lucknow, Uttar Pradesh. Actinobacterial strain LA34 showed promising antifungal activity when screened against Candida albicans and Cryptococcus neoformans, hence selected as potential strain. Antifungal compounds were produced from the strain LA34 using agar surface fermentation and its extraction was done using ethyl acetate and methanol. Results of cultural, microscopic and physiological characteristics as well as cell wall amino acid and sugars analysis revealed that the strain LA34 was nonstreptomyces or rare actinobacterium. Various carbon sources, nitrogen sources and minerals were found to influence antifungal compound production by the strain LA34. The present study concluded that the rare actinobacterial strain LA34 isolated from Lucknow forest soil is a promising source for the isolation of antifungal compounds.

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Low In Vitro Antifungal Activity of Tavaborole against Yeasts and Molds from Onychomycosis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01632-18 ◽

2018 ◽

Vol 62 (12) ◽

Cited By ~ 4

Author(s):

Mahdi Abastabar ◽

Iman Haghani ◽

Tahereh Shokohi ◽

Mohammad Taghi Hedayati ◽

Seyed Reza Aghili ◽

...

Keyword(s):

Antifungal Activity ◽

Antifungal Agents ◽

Antifungal Drug ◽

Content Type ◽

Fungal Isolates ◽

Yeasts And Molds ◽

Low Activity ◽

In Vitro Antifungal Activity

ABSTRACT The in vitro activity of tavaborole, an FDA-approved antifungal drug, was compared to that of four antifungal agents against 170 clinical fungal isolates originating from patients with onychomycosis. Tavaborole had low activity against all isolates compared to itraconazole, terbinafine, and fluconazole, the principal choices for treatment of onychomycosis. Thus, it appears that tavaborole is not a candidate for the treatment of onychomycosis due to Candida species, Aspergillus species, and dermatophytes.

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Novel Antifungal Compounds Discovered in Medicines for Malaria Venture’s Malaria Box

mSphere ◽

10.1128/msphere.00537-17 ◽

2018 ◽

Vol 3 (2) ◽

Cited By ~ 7

Author(s):

Eric H. Jung ◽

David J. Meyers ◽

Jürgen Bosch ◽

Arturo Casadevall

Keyword(s):

Candida Albicans ◽

Antifungal Activity ◽

Cryptococcus Neoformans ◽

Fungal Pathogens ◽

Pathogenic Fungi ◽

Cryptococcus Gattii ◽

Antifungal Drugs ◽

Resistant Bacteria ◽

Animal Cells ◽

Malaria Box

ABSTRACTSimilarities in fungal and animal cells make antifungal discovery efforts more difficult than those for other classes of antimicrobial drugs. Currently, there are only three major classes of antifungal drugs used for the treatment of systemic fungal diseases: polyenes, azoles, and echinocandins. Even in situations where the offending fungal organism is susceptible to the available drugs, treatment courses can be lengthy and unsatisfactory, since eradication of infection is often very difficult, especially in individuals with impaired immunity. Consequently, there is a need for new and more effective antifungal drugs. We have identified compounds with significant antifungal activity in the Malaria Box (Medicines for Malaria Ventures, Geneva, Switzerland) that have higher efficacy than some of the currently used antifungal drugs. Our best candidate, MMV665943 (IUPAC name 4-[6-[[2-(4-aminophenyl)-3H-benzimidazol-5-yl]methyl]-1H-benzimidazol-2-yl]aniline), here referred to as DM262, showed 16- to 32-fold-higher activity than fluconazole againstCryptococcus neoformans. There was also significant antifungal activity in other fungal species with known antifungal resistance, such asLomentospora prolificansandCryptococcus gattii. Antifungal activity was also observed against a common fungus,Candida albicans. These results are important because they offer a potentially new class of antifungal drugs and the repurposing of currently available therapeutics.IMPORTANCEMuch like the recent increase in drug-resistant bacteria, there is a rise in antifungal-resistant strains of pathogenic fungi. There is a need for novel and more potent antifungal therapeutics. Consequently, we investigated a mixed library of drug-like and probe-like compounds with activity inPlasmodiumspp. for activity against two common fungal pathogens,Cryptococcus neoformansandCandida albicans, along with two less common pathogenic species,Lomentospora prolificansandCryptococcus gattii. We uncover a previously uncharacterized drug with higher broad-spectrum antifungal activity than some current treatments. Our findings may eventually lead to a compound added to the arsenal of antifungal therapeutics.

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Identification of Fungal Pathogens in Otomycosis and Their Drug Sensitivity: Our Experience

International Archives of Otorhinolaryngology ◽

10.1055/s-0038-1626702 ◽

2018 ◽

Vol 22 (04) ◽

pp. 400-403 ◽

Cited By ~ 3

Author(s):

Khaled Ali ◽

Mahmood Hamed ◽

Hameda Hassan ◽

Amira Esmail ◽

Abeer Sheneef

Keyword(s):

Enzymatic Activity ◽

Candida Species ◽

Fungal Pathogens ◽

Antifungal Agents ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Antifungal Susceptibility Testing ◽

Antifungal Drugs ◽

High Recurrence Rate ◽

Fungal Culture

Introduction Otomycosis is a common problem in otolaryngology practice. However, we usually encounter some difficulties in its treatment because many patients show resistance to antifungal agents, and present high recurrence rate. Objectives To determine the fungal pathogens that cause otomycosis as well as their susceptibility to the commonly used antifungal agents. Additionally, to discover the main reasons for antifungal resistance. Methods We conducted an experimental descriptive study on 122 patients clinically diagnosed with otomycosis from April 2016 to April 2017. Aural discharge specimens were collected for direct microscopic examination and fungal culture. In vitro antifungal susceptibility testing was performed against the commonly used antifungal drugs. We tested the isolated fungi for their enzymatic activity. Results Positive fungal infection was found in 102 samples. The most common fungal pathogens were Aspergillus and Candida species, with Aspergillus niger being the predominant isolate (51%). The antifungal susceptibility testing showed that mold isolates had the highest sensitivity to voriconazole (93.48%), while the highest resistance was to fluconazole (100%). For yeast, the highest sensitivity was to nystatin (88.24%), followed by amphotericin B (82.35%), and the highest resistance was to terbinafine (100%), followed by Itraconazole (94.12%). Filamentous fungi expressed a high enzymatic ability, making them more virulent. Conclusion The Aspergillus and Candida species are the most common fungal isolates in otomycosis. Voriconazole and Nystatin are the medications of choice for the treatment of otomycosis in our community. The high virulence of fungal pathogens is owed to their high enzymatic activity. Empirical use of antifungals should be discouraged.

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Antifungal activity of various plant oils against yeast isolates from ICU patients

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20173018 ◽

2017 ◽

Vol 5 (7) ◽

pp. 3227

Author(s):

Akansha Suman ◽

Sapna Chauhan ◽

Suman Lata ◽

Rajeev K. Sharma

Keyword(s):

Antifungal Activity ◽

Antifungal Agents ◽

Tertiary Care ◽

Antifungal Drugs ◽

Diffusion Method ◽

Clinical Samples ◽

Plant Oils ◽

Clove Oil ◽

Icu Patients ◽

Long Term Treatment

Background: To evaluate the in-vitro antifungal activity of various essential plant oils against yeast species.Methods: The present study was a prospective study conducted in Department of Microbiology along with Department of Pharmacology at Tertiary care teaching hospital. Various clinical samples from ICU patients were inoculated on Sabourauds Dextrose Agar (SDA) in accordance with the standard methods. Yeast isolates were recovered and identified as per standard recommended procedure. The antifungal activity of plant oils against these isolated yeasts was determined using disc diffusion method. The results were interpreted as <9mm-inactive, 9-12mm-partially active, 13-18mm-very active. Fluconazole and Itraconazole were taken as control drugs.Results: The various yeast isolated were C. albicans, C. tropicals, C. krusei, C. glabrata, C. gulliermondi, C. keyfr, Cryptococcus and Tricosporon. Among essential plant oils, Cinnamon oil and clove oil showed high activity against all isolated yeast species. Olive oil showed least antifungal activity. Fluconazole was resistant in all yeast isolates, while Itraconazole was sensitive to all yeast isolates. Sensitivity of cinnamon and clove oil was statistically significant than Itraconazole.Conclusions: To conclude present study shows the potential of essential plant oils as newer therapeutic alternatives to antifungal drugs. These may be used in combination with antifungal agents to overcome drug resistance, adverse effects and in shortening the long-term treatment with antifungal drugs. Thus, these essential plant oils can be used in future as antifungal agents in azoles resistant strains.

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Setting New Routes for Antifungal Drug Discovery Against Pathogenic Fungi

Current Pharmaceutical Design ◽

10.2174/1381612826666200317125956 ◽

2020 ◽

Vol 26 (14) ◽

pp. 1509-1520 ◽

Cited By ~ 1

Author(s):

Kleber S. Freitas e Silva ◽

Lívia C. Silva ◽

Relber A. Gonçales ◽

Bruno J. Neves ◽

Célia M.A. Soares ◽

...

Keyword(s):

Natural Products ◽

Drug Discovery ◽

Side Effects ◽

Fungal Pathogens ◽

Glyoxylate Cycle ◽

Extended Period ◽

Pathogenic Fungi ◽

Antifungal Drugs ◽

Antifungal Drug ◽

The Glyoxylate Cycle

: Fungal diseases are life-threatening to human health and responsible for millions of deaths around the world. Fungal pathogens lead to a high number of morbidity and mortality. Current antifungal treatment comprises drugs, such as azoles, echinocandins, and polyenes and the cure is not guaranteed. In addition, such drugs are related to severe side effects and the treatment lasts for an extended period. Thus, setting new routes for the discovery of effective and safe antifungal drugs should be a priority within the health care system. The discovery of alternative and efficient antifungal drugs showing fewer side effects is time-consuming and remains a challenge. Natural products can be a source of antifungals and used in combinatorial therapy. The most important natural products are antifungal peptides, antifungal lectins, antifungal plants, and fungi secondary metabolites. Several proteins, enzymes, and metabolic pathways could be targets for the discovery of efficient inhibitor compounds and recently, heat shock proteins, calcineurin, salinomycin, the trehalose biosynthetic pathway, and the glyoxylate cycle have been investigated in several fungal species. HSP protein inhibitors and echinocandins have been shown to have a fungicidal effect against azole-resistant fungi strains. Transcriptomic and proteomic approaches have advanced antifungal drug discovery and pointed to new important specific-pathogen targets. Certain enzymes, such as those from the glyoxylate cycle, have been a target of antifungal compounds in several fungi species. Natural and synthetic compounds inhibited the activity of such enzymes and reduced the ability of fungal cells to transit from mycelium to yeast, proving to be promisor antifungal agents. Finally, computational biology has developed effective approaches, setting new routes for early antifungal drug discovery since normal approaches take several years from discovery to clinical use. Thus, the development of new antifungal strategies might reduce the therapeutic time and increase the quality of life of patients.

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Ruthenium based antifungal compounds and their activity

Research Journal of Chemistry and Environment ◽

10.25303/257rjce17721 ◽

2021 ◽

Vol 25 (7) ◽

pp. 177-182

Author(s):

Rahul Kanaoujiya ◽

Shekhar Srivastava

Keyword(s):

Antifungal Activity ◽

Drug Design ◽

Ruthenium Complexes ◽

Chemical Properties ◽

Antifungal Drugs ◽

Antifungal Drug ◽

Attractive Alternative ◽

Antifungal Compounds ◽

Lower Toxicity ◽

Ruthenium Compounds

Ruthenium is recognized as a highly attractive alternative to platinum since the toxicity of many ruthenium compounds is lower and some complexes are quite selective for antifungal drugs. Ruthenium has various chemical properties these chemical properties are very useful for antifungal drug design. Ruthenium compounds have several types of advantages as antifungal drugs because of lower toxicity. . Ruthenium has unique properties making it of particularly use as fungal in drug design specially in antifungal drugs. Several types of ruthenium complexes and their antifungal activity standards are described here.

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