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Sepúlveda VE, Goldman WE, Matute DR. Genotypic diversity, virulence, and molecular genetic tools in Histoplasma. Microbiol Mol Biol Rev 2024; 88:e0007623. [PMID: 38819148 DOI: 10.1128/mmbr.00076-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024] Open
Abstract
SUMMARYHistoplasmosis is arguably the most common fungal respiratory infection worldwide, with hundreds of thousands of new infections occurring annually in the United States alone. The infection can progress in the lung or disseminate to visceral organs and can be difficult to treat with antifungal drugs. Histoplasma, the causative agent of the disease, is a pathogenic fungus that causes life-threatening lung infections and is globally distributed. The fungus has the ability to germinate from conidia into either hyphal (mold) or yeast form, depending on the environmental temperature. This transition also regulates virulence. Histoplasma and histoplasmosis have been classified as being of emergent importance, and in 2022, the World Health Organization included Histoplasma as 1 of the 19 most concerning human fungal pathogens. In this review, we synthesize the current understanding of the ecological niche, evolutionary history, and virulence strategies of Histoplasma. We also describe general patterns of the symptomatology and epidemiology of histoplasmosis. We underscore areas where research is sorely needed and highlight research avenues that have been productive.
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Affiliation(s)
- Victoria E Sepúlveda
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - William E Goldman
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Daniel R Matute
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Sepúlveda VE, Rader JA, Li JJ, Goldman WE, Matute DR. Phenotypic characterization of cryptic species in the fungal pathogen Histoplasma. mSphere 2024; 9:e0000924. [PMID: 38771035 DOI: 10.1128/msphere.00009-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 04/11/2024] [Indexed: 05/22/2024] Open
Abstract
Histoplasmosis is an endemic mycosis that often presents as a respiratory infection in immunocompromised patients. Hundreds of thousands of new infections are reported annually around the world. The etiological agent of the disease, Histoplasma, is a dimorphic fungus commonly found in the soil where it grows as mycelia. Humans can become infected by Histoplasma through inhalation of its spores (conidia) or mycelial particles. The fungi transition into the yeast phase in the lungs at 37°C. Once in the lungs, yeast cells reside and proliferate inside alveolar macrophages. Genomic work has revealed that Histoplasma is composed of at least five cryptic phylogenetic species that differ genetically. Three of those lineages have received new names. Here, we evaluated multiple phenotypic characteristics (colony morphology, secreted proteolytic activity, yeast size, and growth rate) of strains from five of the phylogenetic species of Histoplasma to identify phenotypic traits that differentiate between these species: Histoplasma capsulatum sensu stricto, Histoplasma ohiense, Histoplasma mississippiense, Histoplasma suramericanum, and an African lineage. We report diagnostic traits for three species. The other two species can be identified by a combination of traits. Our results suggest that (i) there are significant phenotypic differences among the cryptic species of Histoplasma and (ii) those differences can be used to positively distinguish those species in a clinical setting and for further study of the evolution of this fungal pathogen.IMPORTANCEIdentifying species boundaries is a critical component of evolutionary biology. Genome sequencing and the use of molecular markers have advanced our understanding of the evolutionary history of fungal pathogens, including Histoplasma, and have allowed for the identification of new species. This is especially important in organisms where morphological characteristics have not been detected. In this study, we revised the taxonomic status of the four named species of the genus Histoplasma, H. capsulatum sensu stricto (ss), H. ohiense, H. mississippiense, and H. suramericanum, and propose the use of species-specific phenotypic traits to aid their identification when genome sequencing is not available. These results have implications not only for evolutionary study of Histoplasma but also for clinicians, as the Histoplasma species could determine the outcome of disease and treatment needed.
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Affiliation(s)
- Victoria E Sepúlveda
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jonathan A Rader
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jingbaoyi Janet Li
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - William E Goldman
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Daniel R Matute
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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de Matos Silva S, Echeverri CR, Mendes-Giannini MJS, Fusco-Almeida AM, Gonzalez A. Common virulence factors between Histoplasma and Paracoccidioides: Recognition of Hsp60 and Enolase by CR3 and plasmin receptors in host cells. CURRENT RESEARCH IN MICROBIAL SCIENCES 2024; 7:100246. [PMID: 39022313 PMCID: PMC11253281 DOI: 10.1016/j.crmicr.2024.100246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024] Open
Abstract
Over the last two decades, the incidence of Invasive Fungal Infections (IFIs) globally has risen, posing a considerable challenge despite available antifungal therapies. Addressing this, the World Health Organization (WHO) prioritized research on specific fungi, notably Histoplasma spp. and Paracoccidioides spp. These dimorphic fungi have a mycelial life cycle in soil and a yeast phase associated with tissues of mammalian hosts. Inhalation of conidia and mycelial fragments initiates the infection, crucially transforming into the yeast form within the host, influenced by factors like temperature, host immunity, and hormonal status. Survival and multiplication within alveolar macrophages are crucial for disease progression, where innate immune responses play a pivotal role in overcoming physical barriers. The transition to pathogenic yeast, triggered by increased temperature, involves yeast phase-specific gene expression, closely linked to infection establishment and pathogenicity. Cell adhesion mechanisms during host-pathogen interactions are intricately linked to fungal virulence, which is critical for tissue colonization and disease development. Yeast replication within macrophages leads to their rupture, aiding pathogen dissemination. Immune cells, especially macrophages, dendritic cells, and neutrophils, are key players during infection control, with macrophages crucial for defense, tissue integrity, and pathogen elimination. Recognition of common virulence molecules such as heat- shock protein-60 (Hsp60) and enolase by pattern recognition receptors (PRRs), mainly via the complement receptor 3 (CR3) and plasmin receptor pathways, respectively, could be pivotal in host-pathogen interactions for Histoplasma spp. and Paracoccidioides spp., influencing adhesion, phagocytosis, and inflammatory regulation. This review provides a comprehensive overview of the dynamic of these two IFIs between host and pathogen. Further research into these fungi's virulence factors promises insights into pathogenic mechanisms, potentially guiding the development of effective treatment strategies.
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Affiliation(s)
- Samanta de Matos Silva
- Laboratory of Mycology, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
- Nucleous of Proteomics, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
- Basic and Applied Microbiology Group (MICROBA), School of Microbiology, Universidad de Antioquia (UdeA), Medellín, Colombia
| | - Carolina Rodriguez Echeverri
- Laboratory of Mycology, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
- Nucleous of Proteomics, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
- Basic and Applied Microbiology Group (MICROBA), School of Microbiology, Universidad de Antioquia (UdeA), Medellín, Colombia
| | - Maria José Soares Mendes-Giannini
- Laboratory of Mycology, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
- Nucleous of Proteomics, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
| | - Ana Marisa Fusco-Almeida
- Laboratory of Mycology, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
- Nucleous of Proteomics, Department of Clinical Analysis, School of Pharmaceutical Science, Paulista State University (UNESP), Araraquara, Brazil
| | - Angel Gonzalez
- Basic and Applied Microbiology Group (MICROBA), School of Microbiology, Universidad de Antioquia (UdeA), Medellín, Colombia
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Anh Nga NT, Fathima H A, Alahmadi TA. Assessment of possible biomedical applications of green synthesized TiO 2NPs-an in-vitro approach. ENVIRONMENTAL RESEARCH 2024; 248:118278. [PMID: 38246297 DOI: 10.1016/j.envres.2024.118278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/13/2024] [Accepted: 01/19/2024] [Indexed: 01/23/2024]
Abstract
Biomedical applications for various types of nanoparticles are emerging on a daily basis. Hence this research was performed to evaluate the antifungal (Aspergillus sp., Alternaria sp., Trichophyton sp., Candida sp., and Penicillium sp.), cytotoxicity (MCF10A cell lines), and antioxidant (DPPH) potential of Coleus aromaticus mediated and pre-characterized TiO2NPs were studied with respective standard methodology. Interestingly, the TiO2NPs exhibited significant antifungal activity on pathogenic fungal strains like Alternaria sp., Aspergillus sp. (31 ± 1.4), Penicillium sp. (31 ± 1.9) Trichophyton sp. (27 ± 2.1), and Candida sp. (26 ± 2.3) at high concentration (250 μg mL-1). However, the considerable levels of zone of inhibitions on fungal pathogens were recorded at 100 μg mL-1 of TiO2NPs as well as it was considerably greater than positive control. It also demonstrated dose based anti-inflammatory and antidiabetic activities. The plant-mediated TiO2NPs demonstrated a maximum DPPH scavenging efficiency of 91% at a dosage of 250 μg mL-1, comparable to the positive control's 94%. Furthermore, TiO2NPs at 100 μg mL-1 concentration did not cause cytotoxicity in MCF10A cell lines. At higher concentrations (250 μg mL-1), the nanoparticles showed the lowest cytotoxicity (17%). These findings suggest that C. aromaticus-mediated TiO2NPs have significant biomedical applications. However, in-vivo studies are needed to learn more about their (C. aromaticus-mediated TiO2NPs) potential biomedical applications.
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Affiliation(s)
- Nguyen Thi Anh Nga
- Biomaterials and Nanotechnology Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
| | - Aafreen Fathima H
- Center for Global Health Research, Saveetha Medical College, Saveetha Institute of Medical and Technical Sciences, India
| | - Tahani Awad Alahmadi
- Department of Pediatrics, College of Medicine and King Khalid University Hospital, King Saud University, Medical City, PO Box-2925, Riyadh, 11461, Saudi Arabia
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Girma T, Chala G, Mekibib B. Growth inhibitory effect of selected medicinal plants from Southern Ethiopia on the mycelial phase of Histoplasma capsulatum var. farciminosum. BMC Vet Res 2024; 20:27. [PMID: 38243346 PMCID: PMC10797924 DOI: 10.1186/s12917-023-03873-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 12/28/2023] [Indexed: 01/21/2024] Open
Abstract
BACKGROUND Epizootic lymphangitis is an infectious and chronically debilitating disease of the equines. Histoplasma capsulatum var. farciminosum, a thermally dimorphic fungi, is the causative agent for the disease. In Ethiopia, the disease significantly affects carthorses, posing threats to animal welfare, and resulting in substantial economic losses. Limited availability of widely accessible antifungals in addition to the chronic nature of the disease is the major challenge against management of epizootic lymphangitis. This study aimed to assess the in vitro efficacy of specific local medicinal plant extracts against the mycelial phase development of H. capsulatum var. farciminosum in southern Ethiopia. The leaves of Xanthium strumarium, Kanda (Family Rubiaceae), Croton macrostachyus (Bisana in Amharic), and Centella Asiatica (Echere waye as a local name in Zeyissegna) that are traditionally used for the treatment of different skin ailments were collected and extracted for the in vitro trial. RESULTS The study revealed that methanol extracts of Xanthium strumarium, Kanda, Croton macrostachyus, and Centella Asiatica, at minimum inhibitory concentrations of 1.25 mg/ml, 2.5 mg/ml, 2.5 mg/ml, and 5 mg/ml, respectively, inhibited the growth of H. capsulatum var. farciminosum. CONCLUSION This in vitro finding could serve as significant preliminary data in the exploration of effective alternative treatment options for epizootic lymphangitis. This study provides a crucial foundation for further research aimed at determining the chemical components and in vivo effectiveness of these plant extracts against both the mycelial and yeast forms of Histoplasma capsulatum var. farciminosum.
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Affiliation(s)
- Tagash Girma
- Faculty of Veterinary Medicine, Hawassa University, Hawassa, Ethiopia
| | - Gemechu Chala
- Faculty of Veterinary Medicine, Hawassa University, Hawassa, Ethiopia.
| | - Berhanu Mekibib
- Faculty of Veterinary Medicine, Hawassa University, Hawassa, Ethiopia
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Sepúlveda VE, Rader JA, Li J(J, Goldman WE, Matute DR. Phenotypic characterization of cryptic species in the fungal pathogen Histoplasma. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.08.574719. [PMID: 38260643 PMCID: PMC10802462 DOI: 10.1101/2024.01.08.574719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Histoplasmosis is an endemic mycosis that often presents as a respiratory infection in immunocompromised patients. Hundreds of thousands of new infections are reported annually around the world. The etiological agent of the disease, Histoplasma, is a dimorphic fungus commonly found in the soil where it grows as mycelia. Humans can become infected by Histoplasma through inhalation of its spores (conidia) or mycelial particles. The fungi transitions into the yeast phase in the lungs at 37°C. Once in the lungs, yeast cells reside and proliferate inside alveolar macrophages. We have previously described that Histoplasma is composed of at least five cryptic species that differ genetically, and assigned new names to the lineages. Here we evaluated multiple phenotypic characteristics of 12 strains from five phylogenetic species of Histoplasma to identify phenotypic traits that differentiate between these species: H. capsulatum sensu stricto, H. ohiense, H. mississippiense, H. suramericanum, and an African lineage. We report diagnostic traits for two species. The other three species can be identified by a combination of traits. Our results suggest that 1) there are significant phenotypic differences among the cryptic species of Histoplasma, and 2) that those differences can be used to positively distinguish those species in a clinical setting and for further study of the evolution of this fungal pathogen.
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Affiliation(s)
| | | | | | - William E. Goldman
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill
| | - Daniel R. Matute
- Department of Biology, University of North Carolina at Chapel Hill
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Poester VR, Munhoz LS, Stevens DA, Melo AM, Trápaga MR, Flores MM, Larwood DJ, Xavier MO. Nikkomycin Z for the treatment of experimental sporotrichosis caused by Sporothrix brasiliensis. Mycoses 2023; 66:898-905. [PMID: 37434420 DOI: 10.1111/myc.13629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 06/27/2023] [Accepted: 06/30/2023] [Indexed: 07/13/2023]
Abstract
Sporotrichosis caused by Sporothrix brasiliensis is a global emergent infectious disease. Due to the scarcity of therapeutic options for fungal diseases, new antifungals are urgently needed. Nikkomycin Z (NikZ) is a future option as an agent against dimorphic fungi. We evaluated NikZ monotherapy and in combination with itraconazole (ITZ; the conventional therapy) in the treatment of experimental sporotrichosis caused by S. brasiliensis in a murine model. Animals were subcutaneously infected, and treated orally for 30 days. The study groups were as follows control (untreated), ITZ group (50 mg/kg/day), and three groups treated with NikZ, two by monotherapy (200 or 400 mg/kg/day), and one combining NikZ (400 mg/kg/day) and ITZ. Efficacy of treatments was evaluated via body weight gain, mortality and fungal burden in tissues. Efficacy was noted in all treatment groups, and the group receiving the drug combination showed even better results than those with monotherapy. Our study shows for the first time the high potential of NikZ to be used in the treatment of sporotrichosis caused by S. brasiliensis.
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Affiliation(s)
- Vanice Rodrigues Poester
- Programa de Pós-Graduação em Ciências da Saúde, Faculdade de Medicina (FAMED), Universidade Federal do Rio Grande (FURG), Rio Grande, Brazil
- Mycology Laboratory of FAMED-FURG, Rio Grande, Brazil
| | | | - David A Stevens
- California Institute for Medical Research, San Jose, California, USA
- Division of Infectious Diseases and Geographic Medicine, Stanford University Medical School, Stanford, California, USA
| | - Aryse Martins Melo
- Department of Infectious Diseases, National Institute of Health Doutor Ricardo Joge, Lisbon, Portugal
| | - Mariana Rodrigues Trápaga
- Programa de Pós-Graduação em Ciências da Saúde, Faculdade de Medicina (FAMED), Universidade Federal do Rio Grande (FURG), Rio Grande, Brazil
- Mycology Laboratory of FAMED-FURG, Rio Grande, Brazil
| | | | - David J Larwood
- California Institute for Medical Research, San Jose, California, USA
- Valley Fever Solutions, Tucson, Arizona, USA
| | - Melissa Orzechowski Xavier
- Programa de Pós-Graduação em Ciências da Saúde, Faculdade de Medicina (FAMED), Universidade Federal do Rio Grande (FURG), Rio Grande, Brazil
- Mycology Laboratory of FAMED-FURG, Rio Grande, Brazil
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Abstract
Candida auris is a multidrug-resistant fungal pathogen that presents a serious threat to global human health. Since the first reported case in 2009 in Japan, C. auris infections have been reported in more than 40 countries, with mortality rates between 30% and 60%. In addition, C. auris has the potential to cause outbreaks in health care settings, especially in nursing homes for elderly patients, owing to its efficient transmission via skin-to-skin contact. Most importantly, C. auris is the first fungal pathogen to show pronounced and sometimes untreatable clinical drug resistance to all known antifungal classes, including azoles, amphotericin B, and echinocandins. In this review, we explore the causes of the rapid spread of C. auris. We also highlight its genome organization and drug resistance mechanisms and propose future research directions that should be undertaken to curb the spread of this multidrug-resistant pathogen.
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Affiliation(s)
- Anuradha Chowdhary
- Medical Mycology Unit, Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India;
- National Reference Laboratory for Antimicrobial Resistance in Fungal Pathogens, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Kusum Jain
- Medical Mycology Unit, Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India;
| | - Neeraj Chauhan
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
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New Methylcitrate Synthase Inhibitor Induces Proteolysis, Lipid Degradation and Pyruvate Excretion in Paracoccidioides brasiliensis. J Fungi (Basel) 2023; 9:jof9010108. [PMID: 36675929 PMCID: PMC9865517 DOI: 10.3390/jof9010108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/08/2023] [Accepted: 01/11/2023] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Paracoccidioidomycosis is a systemic mycosis caused by the inhalation of conidia of the genus Paracoccidioides. During the infectious process, fungal cells use several carbon sources, leading to the production of propionyl-CoA. The latter is metabolized by the methylcitrate synthase, a key enzyme of the methylcitrate cycle. We identified an inhibitor compound (ZINC08964784) that showed antifungal activity against P. brasiliensis. METHODS This work aimed to understand the fungal metabolic response of P. brasiliensis cells exposed to ZINC08964784 through a proteomics approach. We used a glucose-free medium supplemented with propionate in order to simulate the environment found by the pathogen during the infection. We performed pyruvate dosage, proteolytic assay, dosage of intracellular lipids and quantification of reactive oxygen species in order to validate the proteomic results. RESULTS The proteomic analysis indicated that the fungal cells undergo a metabolic shift due to the inhibition of the methylcitrate cycle and the generation of reactive species. Proteolytic enzymes were induced, driving amino acids into degradation for energy production. In addition, glycolysis and the citric acid cycle were down-regulated while ß-oxidation was up-regulated. The accumulation of pyruvate and propionyl-CoA led the cells to a state of oxidative stress in the presence of ZINC08964784. CONCLUSIONS The inhibition of methylcitrate synthase caused by the compound promoted a metabolic shift in P. brasiliensis damaging energy production and generating oxidative stress. Hence, the compound is a promising alternative for developing new strategies of therapies against paracoccidioidomycosis.
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Rappleye CA. Antifungal Susceptibility Testing and Drug Discovery in the Dimorphic Fungus Histoplasma Capsulatum. Methods Mol Biol 2023; 2658:43-52. [PMID: 37024694 DOI: 10.1007/978-1-0716-3155-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
The thermal dimorphism of the fungal pathogen Histoplasma is linked to its virulence in mammalian hosts. Mammalian body temperature triggers differentiation of the fungus into virulent yeasts which successfully infect host phagocytes. Accurate determination of antifungal susceptibility with relevance to infection requires that the tests be performed specifically using the yeast form, not the filamentous environmental form. However, traditional CLSI methodology for antifungal susceptibility testing of yeasts with Histoplasma is in adequate. We present optimized methodology for performing antifungal susceptibility assays on Histoplasma yeasts with an emphasis on quantitative yeast growth determination. Colorimetric and fluorometric assays for Histoplasma growth overcome challenges associated with quantifying some Histoplasma strains which grow as aggregates of yeasts. We also describe antifungal susceptibility testing of Histoplasma yeasts within macrophages to provide improved accuracy and better physiological relevance of antifungal susceptibility profiles.
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Affiliation(s)
- Chad A Rappleye
- Department of Microbiology, Ohio State University, Columbus, OH, USA.
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Borba-Santos LP, Rollin-Pinheiro R, da Silva Fontes Y, dos Santos GMP, de Sousa Araújo GR, Rodrigues AM, Guimarães AJ, de Souza W, Frases S, Ferreira-Pereira A, Barreto-Bergter E, Rozental S. Screening of Pandemic Response Box Library Reveals the High Activity of Olorofim against Pathogenic Sporothrix Species. J Fungi (Basel) 2022; 8:jof8101004. [PMID: 36294569 PMCID: PMC9605001 DOI: 10.3390/jof8101004] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/19/2022] [Accepted: 09/22/2022] [Indexed: 11/16/2022] Open
Abstract
The increase in the prevalence and severity of fungal infections and the resistance to available antifungals highlights the imperative need for novel therapeutics and the search for new targets. High-content screening of libraries containing hundreds of compounds is a powerful strategy for searching for new drug candidates. In this study, we screened the Pandemic Response Box library (Medicines for Malaria Venture) of 400 diverse molecules against the Sporothrix pathogenic species. The initial screen identified twenty-four candidates that inhibited the growth of Sporothrix brasiliensis by more than 80%. Some of these compounds are known to display antifungal activity, including olorofim (MMV1782354), a new antifungal drug. Olorofim inhibited and killed the yeasts of S. brasiliensis, S. schenckii, and S. globosa at concentrations lower than itraconazole, and it also showed antibiofilm activity. According to the results obtained by fluorimetry, electron microscopy, and particle characterization analyses, we observed that olorofim induced profound alterations on the cell surface and cell cycle arrest in S. brasiliensis yeasts. We also verified that these morphophysiological alterations impaired their ability to adhere to keratinocytes in vitro. Our results indicate that olorofim is a promising new antifungal against sporotrichosis agents.
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Affiliation(s)
- Luana Pereira Borba-Santos
- Laboratório de Biologia Celular de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Correspondence: ; Tel.: +55-21-39386569
| | - Rodrigo Rollin-Pinheiro
- Laboratório de Química Biológica de Microrganismos, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Yasmin da Silva Fontes
- Laboratório de Bioquímica Microbiana, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Giulia Maria Pires dos Santos
- Laboratório de Biologia Celular de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Laboratório de Química Biológica de Microrganismos, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Glauber Ribeiro de Sousa Araújo
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Anderson Messias Rodrigues
- Laboratório de Patógenos Fúngicos Emergentes, Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo 04023-062, Brazil
| | - Allan J. Guimarães
- Laboratório de Bioquímica e Imunologia das Micoses, Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói 24210-130, Brazil
| | - Wanderley de Souza
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Susana Frases
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Antonio Ferreira-Pereira
- Laboratório de Bioquímica Microbiana, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Eliana Barreto-Bergter
- Laboratório de Química Biológica de Microrganismos, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Sonia Rozental
- Laboratório de Biologia Celular de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
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Shivarathri R, Jenull S, Chauhan M, Singh A, Mazumdar R, Chowdhary A, Kuchler K, Chauhan N. Comparative Transcriptomics Reveal Possible Mechanisms of Amphotericin B Resistance in Candida auris. Antimicrob Agents Chemother 2022; 66:e0227621. [PMID: 35652307 PMCID: PMC9211394 DOI: 10.1128/aac.02276-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 05/11/2022] [Indexed: 12/27/2022] Open
Abstract
Candida auris is an emerging multidrug-resistant human fungal pathogen often refractory to treatment by all classes of antifungal drugs. Amphotericin B (AmB) is a fungicidal drug that, despite its toxic side effects, remains a drug of choice for the treatment of drug-resistant fungal infections, including those caused by C. auris. However, the molecular mechanisms underlying AmB resistance are poorly understood. In this study, we present data that suggests membrane lipid alterations and chromatin modifications are critical processes that may contribute to or cause adaptive AmB resistance in clinical C. auris isolates. To determine the plausible cause of increased AmB resistance, we performed RNA-seq of AmB-resistant and sensitive C. auris isolates. Remarkably, AmB-resistant strains show a pronounced enrichment of genes involved in lipid and ergosterol biosynthesis, adhesion, drug transport as well as chromatin remodeling. The transcriptomics data confirm increased adhesion and reduced lipid membrane permeability of AmB-resistant strains compared to the sensitive isolates. The AmB-resistant strains also display hyper-resistance to cell wall perturbing agents, including Congo red, calcofluor white and caffeine. Additionally, we noticed an increased phosphorylation of Mkc1 cell integrity MAP kinase upon AmB treatment. Collectively, these data identify differences in the transcriptional landscapes of AmB-resistant versus AmB-sensitive isolates and provide a framework for the mechanistic understanding of AmB resistance in C. auris.
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Affiliation(s)
- Raju Shivarathri
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, USA
| | - Sabrina Jenull
- Department of Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Medical University of Vienna, Vienna, Austria
- Functional Microbiology, Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Manju Chauhan
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, USA
| | - Ashutosh Singh
- Medical Mycology Unit, Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
- National Reference Laboratory for Antimicrobial Resistance in Fungal Pathogens, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Rounik Mazumdar
- Department of Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Medical University of Vienna, Vienna, Austria
| | - Anuradha Chowdhary
- Medical Mycology Unit, Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
- National Reference Laboratory for Antimicrobial Resistance in Fungal Pathogens, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Karl Kuchler
- Department of Medical Biochemistry, Max Perutz Labs Vienna, Campus Vienna Biocenter, Medical University of Vienna, Vienna, Austria
| | - Neeraj Chauhan
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, USA
- Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey, USA
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13
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Evaluation of the Anti-Histoplasma capsulatum Activity of Indole and Nitrofuran Derivatives and Their Pharmacological Safety in Three-Dimensional Cell Cultures. Pharmaceutics 2022; 14:pharmaceutics14051043. [PMID: 35631629 PMCID: PMC9147190 DOI: 10.3390/pharmaceutics14051043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/04/2022] [Accepted: 05/09/2022] [Indexed: 11/25/2022] Open
Abstract
Histoplasma capsulatum is a fungus that causes histoplasmosis. The increased evolution of microbial resistance and the adverse effects of current antifungals help new drugs to emerge. In this work, fifty-four nitrofurans and indoles were tested against the H. capsulatum EH-315 strain. Compounds with a minimum inhibitory concentration (MIC90) equal to or lower than 7.81 µg/mL were selected to evaluate their MIC90 on ATCC G217-B strain and their minimum fungicide concentration (MFC) on both strains. The quantification of membrane ergosterol, cell wall integrity, the production of reactive oxygen species, and the induction of death by necrosis–apoptosis was performed to investigate the mechanism of action of compounds 7, 11, and 32. These compounds could reduce the extracted sterol and induce necrotic cell death, similarly to itraconazole. Moreover, 7 and 11 damaged the cell wall, causing flaws in the contour (11), or changing the size and shape of the fungal cell wall (7). Furthermore, 7 and 32 induced reactive oxygen species (ROS) formation higher than 11 and control. Finally, the cytotoxicity was measured in two models of cell culture, i.e., monolayers (cells are flat) and a three-dimensional (3D) model, where they present a spheroidal conformation. Cytotoxicity assays in the 3D model showed a lower toxicity in the compounds than those performed on cell monolayers. Overall, these results suggest that derivatives of nitrofurans and indoles are promising compounds for the treatment of histoplasmosis.
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14
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Abstract
Lipids play a fundamental role in fungal cell biology, being essential cell membrane components and major targets of antifungal drugs. A deeper knowledge of lipid metabolism is key for developing new drugs and a better understanding of fungal pathogenesis. Here, we built a comprehensive map of the Histoplasma capsulatum lipid metabolic pathway by incorporating proteomic and lipidomic analyses. We performed genetic complementation and overexpression of H. capsulatum genes in Saccharomyces cerevisiae to validate reactions identified in the map and to determine enzymes responsible for catalyzing orphan reactions. The map led to the identification of both the fatty acid desaturation and the sphingolipid biosynthesis pathways as targets for drug development. We found that the sphingolipid biosynthesis inhibitor myriocin, the fatty acid desaturase inhibitor thiocarlide, and the fatty acid analog 10-thiastearic acid inhibit H. capsulatum growth in nanomolar to low-micromolar concentrations. These compounds also reduced the intracellular infection in an alveolar macrophage cell line. Overall, this lipid metabolic map revealed pathways that can be targeted for drug development.
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15
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Liu T, Pyle AM. Discovery of highly reactive self-splicing group II introns within the mitochondrial genomes of human pathogenic fungi. Nucleic Acids Res 2021; 49:12422-12432. [PMID: 34850132 PMCID: PMC8643640 DOI: 10.1093/nar/gkab1077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/27/2021] [Accepted: 10/20/2021] [Indexed: 11/25/2022] Open
Abstract
Fungal pathogens represent an expanding global health threat for which treatment options are limited. Self-splicing group II introns have emerged as promising drug targets, but their development has been limited by a lack of information on their distribution and architecture in pathogenic fungi. To meet this challenge, we developed a bioinformatic workflow for scanning sequence data to identify unique RNA structural signatures within group II introns. Using this approach, we discovered a set of ubiquitous introns within thermally dimorphic fungi (genera of Blastomyces, Coccidioides and Histoplasma). These introns are the most biochemically reactive group II introns ever reported, and they self-splice rapidly under near-physiological conditions without protein cofactors. Moreover, we demonstrated the small molecule targetability of these introns by showing that they can be inhibited by the FDA-approved drug mitoxantrone in vitro. Taken together, our results highlight the utility of structure-based informatic searches for identifying riboregulatory elements in pathogens, revealing a striking diversity of reactive self-splicing introns with great promise as antifungal drug targets.
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Affiliation(s)
- Tianshuo Liu
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06520, USA
| | - Anna M Pyle
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06520, USA.,Department of Chemistry, Yale University, New Haven, CT, 06520, USA.,Howard Hughes Medical Institute, Yale University, New Haven, CT, 06520, USA
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16
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Navarro MV, de Barros YN, Segura WD, Chaves AFA, Jannuzzi GP, Ferreira KS, Xander P, Batista WL. The Role of Dimorphism Regulating Histidine Kinase (Drk1) in the Pathogenic Fungus Paracoccidioides brasiliensis Cell Wall. J Fungi (Basel) 2021; 7:jof7121014. [PMID: 34946996 PMCID: PMC8707131 DOI: 10.3390/jof7121014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/09/2021] [Accepted: 11/24/2021] [Indexed: 11/16/2022] Open
Abstract
Dimorphic fungi of the Paracoccidioides genus are the causative agents of paracoccidioidomycosis (PCM), an endemic disease in Latin America with a high incidence in Brazil. This pathogen presents as infective mycelium at 25 °C in the soil, reverting to its pathogenic form when inhaled by the mammalian host (37 °C). Among these dimorphic fungal species, dimorphism regulating histidine kinase (Drk1) plays an essential role in the morphological transition. These kinases are present in bacteria and fungi but absent in mammalian cells and are important virulence and cellular survival regulators. Hence, the purpose of this study was to investigate the role of PbDrk1 in the cell wall modulation of P. brasiliensis. We observed that PbDrk1 participates in fungal resistance to different cell wall-disturbing agents by reducing viability after treatment with iDrk1. To verify the role of PbDRK1 in cell wall morphogenesis, qPCR results showed that samples previously exposed to iDrk1 presented higher expression levels of several genes related to cell wall modulation. One of them was FKS1, a β-glucan synthase that showed a 3.6-fold increase. Furthermore, confocal microscopy analysis and flow cytometry showed higher β-glucan exposure on the cell surface of P. brasiliensis after incubation with iDrk1. Accordingly, through phagocytosis assays, a significantly higher phagocytic index was observed in yeasts treated with iDrk1 than the control group, demonstrating the role of PbDrk1 in cell wall modulation, which then becomes a relevant target to be investigated. In parallel, the immune response profile showed increased levels of proinflammatory cytokines. Finally, our data strongly suggest that PbDrk1 modulates cell wall component expression, among which we can identify β-glucan. Understanding this signalling pathway may be of great value for identifying targets of antifungal molecular activity since HKs are not present in mammals.
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Affiliation(s)
- Marina Valente Navarro
- Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo, São Paulo 04023-062, Brazil;
| | - Yasmin Nascimento de Barros
- Department of Pharmaceutical Sciences, Federal University of São Paulo, Diadema 09913-030, Brazil; (Y.N.d.B.); (W.D.S.); (K.S.F.); (P.X.)
| | - Wilson Dias Segura
- Department of Pharmaceutical Sciences, Federal University of São Paulo, Diadema 09913-030, Brazil; (Y.N.d.B.); (W.D.S.); (K.S.F.); (P.X.)
| | | | - Grasielle Pereira Jannuzzi
- Department of Clinical and Toxicological Analyses, University of São Paulo, São Paulo 05508-000, Brazil;
| | - Karen Spadari Ferreira
- Department of Pharmaceutical Sciences, Federal University of São Paulo, Diadema 09913-030, Brazil; (Y.N.d.B.); (W.D.S.); (K.S.F.); (P.X.)
| | - Patrícia Xander
- Department of Pharmaceutical Sciences, Federal University of São Paulo, Diadema 09913-030, Brazil; (Y.N.d.B.); (W.D.S.); (K.S.F.); (P.X.)
| | - Wagner Luiz Batista
- Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo, São Paulo 04023-062, Brazil;
- Department of Pharmaceutical Sciences, Federal University of São Paulo, Diadema 09913-030, Brazil; (Y.N.d.B.); (W.D.S.); (K.S.F.); (P.X.)
- Correspondence: ; Tel.: +55-11-3319-3594; Fax: +55-11-3319-3300
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17
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Lima RM, Freitas E Silva KS, Silva LDC, Ribeiro JFR, Neves BJ, Brock M, Soares CMDA, da Silva RA, Pereira M. A structure-based approach for the discovery of inhibitors against methylcitrate synthase of Paracoccidioides lutzii. J Biomol Struct Dyn 2021; 40:9361-9373. [PMID: 34060981 DOI: 10.1080/07391102.2021.1930584] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Paracoccidioidomycosis (PCM) is a systemic mycosis, endemic in Latin America, caused by fungi of the genus Paracoccidioides. The treatment of PCM is complex, requiring a long treatment period, which often results in serious side effects. The aim of this study was to screen for inhibitors of a specific target of the fungus that is absent in humans. Methylcitrate synthase (MCS) is a unique enzyme of microorganisms and is responsible for the synthesis of methylcitrate at the beginning of the propionate degradation pathway. This pathway is essential for several microorganisms, since the accumulation of propionyl-CoA can impair virulence and prevent the development of the pathogen. We performed the modeling and molecular dynamics of the structure of Paracoccidioides lutzii MCS (PlMCS) and performed a virtual screening on 89,415 compounds against the active site of the enzyme. The compounds were selected according to the affinity and efficiency criteria of in vitro tests. Six compounds were able to inhibit the enzymatic activity of recombinant PlMCS but only the compound ZINC08964784 showed fungistatic and fungicidal activity against Paracoccidioides spp. cells. The analysis of the interaction profile of this compound with PlMCS showed its effectiveness in terms of specificity and stability when compared to the substrate (propionyl-CoA) of the enzyme. In addition, this compound did not show cytotoxicity in mammalian cells, with an excellent selectivity index. Our results suggest that the compound ZINC08964784 may become a promising alternative antifungal against Paracoccidioides spp. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Raisa Melo Lima
- Molecular Biology Laboratory, Institute of Biological Sciences, Federal University of Goiás, Brazil.,Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Brazil
| | | | - Lívia do Carmo Silva
- Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Brazil
| | | | - Bruno Junior Neves
- Faculty of Pharmacy, Laboratory for Molecular Modeling and Drug Design, Federal University of Goiás, Goiânia, Brazil
| | - Matthias Brock
- School of Life Science, Fungal Biology Group, University of Nottingham, Nottingham, UK
| | | | - Roosevelt Alves da Silva
- Collaborative Nucleus of Biosystems, Institute of Exact Sciences, Federal University of Jataí, Jataí, Brazil
| | - Maristela Pereira
- Molecular Biology Laboratory, Institute of Biological Sciences, Federal University of Goiás, Brazil.,Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Brazil
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18
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McKinsey DS. Treatment and Prevention of Histoplasmosis in Adults Living with HIV. J Fungi (Basel) 2021; 7:jof7060429. [PMID: 34071599 PMCID: PMC8229061 DOI: 10.3390/jof7060429] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 05/22/2021] [Accepted: 05/25/2021] [Indexed: 11/16/2022] Open
Abstract
Histoplasmosis causes life-threatening disseminated infection in adult patients living with untreated HIV. Although disease incidence has declined dramatically in countries with access to antiretroviral therapy, histoplasmosis remains prevalent in many resource-limited regions. A high index of suspicion for histoplasmosis should be maintained in the setting of a febrile multisystem illness in severely immunosuppressed patients, particularly in persons with hemophagocytic lymphohistiocytosis. Preferred treatment regimens for initial therapy include liposomal amphotericin B for severe disease, or itraconazole for mild to moderate disease. Subsequently, itraconazole maintenance therapy should be administered for at least one year and then discontinued if CD4 count increases to ≥150 cells/µL. Antiretroviral therapy, which improves outcome when administered together with an antifungal agent, should be instituted immediately, as the risk of triggering Immune Reconstitution Syndrome is low. The major risk factor for relapsed infection is nonadherence. Itraconazole prophylaxis reduces risk for histoplasmosis in patients with CD4 counts <100/µL but is not associated with survival benefit and is primarily reserved for use in outbreaks. Although most patients with histoplasmosis have not had recognized high-risk exposures, avoidance of contact with bird or bat guano or inhalation of aerosolized soil in endemic regions may reduce risk. Adherence to effective antiretroviral therapy is the most important strategy for reducing the incidence of life-threatening histoplasmosis.
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Affiliation(s)
- David S McKinsey
- Metro Infectious Disease Consultants, Kansas City, MO 64132, USA
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19
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Samaddar A, Sharma A. Emergomycosis, an Emerging Systemic Mycosis in Immunocompromised Patients: Current Trends and Future Prospects. Front Med (Lausanne) 2021; 8:670731. [PMID: 33968970 PMCID: PMC8104006 DOI: 10.3389/fmed.2021.670731] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 03/31/2021] [Indexed: 02/06/2023] Open
Abstract
Recently, the global emergence of emergomycosis, a systemic fungal infection caused by a novel dimorphic fungus Emergomyces species has been observed among immunocompromised individuals. Though initially classified under the genus Emmonsia, a taxonomic revision in 2017 based on DNA sequence analyses placed five Emmonsia-like fungi under a separate genus Emergomyces. These include Emergomyces pasteurianus, Emergomyces africanus, Emergomyces canadensis, Emergomyces orientalis, and Emergomyces europaeus. Emmonsia parva was renamed as Blastomyces parvus, while Emmonsia crescens and Emmonsia sola remained within the genus Emmonsia until a taxonomic revision in 2020 placed both the species under the genus Emergomyces. However, unlike other members of the genus, Emergomyces crescens and Emergomyces sola do not cause disseminated disease. The former causes adiaspiromycosis, a granulomatous pulmonary disease, while the latter has not been associated with human disease. So far, emergomycosis has been mapped across four continents: Asia, Europe, Africa and North America. However, considering the increasing prevalence of HIV/AIDS, it is presumed that the disease must have a worldwide distribution with many cases going undetected. Diagnosis of emergomycosis remains challenging. It should be considered in the differential diagnosis of histoplasmosis as there is considerable clinical and histopathological overlap between the two entities. Sequencing the internal transcribed spacer region of ribosomal DNA is considered as the gold standard for identification, but its application is compromised in resource limited settings. Serological tests are non-specific and demonstrate cross-reactivity with Histoplasma galactomannan antigen. Therefore, an affordable, accessible, and reliable diagnostic test is the need of the hour to enable its diagnosis in endemic regions and also for epidemiological surveillance. Currently, there are no consensus guidelines for the treatment of emergomycosis. The recommended regimen consists of amphotericin B (deoxycholate or liposomal formulation) for 1–2 weeks, followed by oral itraconazole for at least 12 months. This review elaborates the taxonomic, clinical, diagnostic, and therapeutic aspects of emergomycosis. It also enumerates several novel antifungal drugs which might hold promise in the treatment of this condition and therefore, can be potential areas of future studies.
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Affiliation(s)
- Arghadip Samaddar
- Department of Microbiology, All India Institute of Medical Sciences, Jodhpur, India
| | - Anuradha Sharma
- Department of Microbiology, All India Institute of Medical Sciences, Jodhpur, India
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20
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Mechanism of Antifungal Activity by 5-Aminoimidazole-4-Carbohydrazonamide Derivatives against Candida albicans and Candida krusei. Antibiotics (Basel) 2021; 10:antibiotics10020183. [PMID: 33673152 PMCID: PMC7917925 DOI: 10.3390/antibiotics10020183] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/05/2021] [Accepted: 02/08/2021] [Indexed: 12/30/2022] Open
Abstract
Systemic mycoses are one major cause of morbidity/mortality among immunocompromised/debilitated individuals. Studying the mechanism of action is a strategy to develop safer/potent antifungals, warning resistance emergence. The major goal of this study was to elucidate the mechanism of action of three (Z)-5-amino-N’-aryl-1-methyl-1H-imidazole-4-carbohydrazonamides (2h, 2k, 2l) that had previously demonstrated strong antifungal activity against Candida krusei and C. albicans ATCC strains. Activity was confirmed against clinical isolates, susceptible or resistant to fluconazole by broth microdilution assay. Ergosterol content (HPLC-DAD), mitochondrial dehydrogenase activity (MTT), reactive oxygen species (ROS) generation (flow cytometry), germ tube inhibition and drug interaction were evaluated. None of the compounds inhibited ergosterol synthesis. Ascorbic acid reduced the antifungal effect of compounds and significantly decreased ROS production. The metabolic viability of C. krusei was significantly reduced for values of 2MIC. Compounds 2h and 2k caused a significant increase in ROS production for MIC values while for 2l a significant increase was only observed for concentrations above MIC. ROS production seems to be involved in antifungal activity and the higher activity against C. krusei versus C. albicans may be related to their unequal sensitivity to different ROS. No synergism with fluconazole or amphotericin was observed, but the association of 2h with fluconazole might be valuable due to the significant inhibition of the dimorphic transition, a C. albicans virulence mechanism.
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21
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McErlean M, Liu X, Cui Z, Gust B, Van Lanen SG. Identification and characterization of enzymes involved in the biosynthesis of pyrimidine nucleoside antibiotics. Nat Prod Rep 2021; 38:1362-1407. [PMID: 33404015 DOI: 10.1039/d0np00064g] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covering: up to September 2020 Hundreds of nucleoside-based natural products have been isolated from various microorganisms, several of which have been utilized in agriculture as pesticides and herbicides, in medicine as therapeutics for cancer and infectious disease, and as molecular probes to study biological processes. Natural products consisting of structural modifications of each of the canonical nucleosides have been discovered, ranging from simple modifications such as single-step alkylations or acylations to highly elaborate modifications that dramatically alter the nucleoside scaffold and require multiple enzyme-catalyzed reactions. A vast amount of genomic information has been uncovered the past two decades, which has subsequently allowed the first opportunity to interrogate the chemically intriguing enzymatic transformations for the latter type of modifications. This review highlights (i) the discovery and potential applications of structurally complex pyrimidine nucleoside antibiotics for which genetic information is known, (ii) the established reactions that convert the canonical pyrimidine into a new nucleoside scaffold, and (iii) the important tailoring reactions that impart further structural complexity to these molecules.
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Affiliation(s)
- M McErlean
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
| | - X Liu
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
| | - Z Cui
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
| | - B Gust
- Pharmaceutical Institute, Department of Pharmaceutical Biology, University of Tübingen, Germany
| | - S G Van Lanen
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
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22
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Larwood DJ. Nikkomycin Z-Ready to Meet the Promise? J Fungi (Basel) 2020; 6:E261. [PMID: 33143248 PMCID: PMC7712250 DOI: 10.3390/jof6040261] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/19/2020] [Accepted: 10/22/2020] [Indexed: 12/15/2022] Open
Abstract
Nikkomycin Z (NikZ) has fungicidal activity against some fungal species which currently requires patients to endure chronic therapy, sometimes for years. This review highlights reports of NikZ activity against fungal species for which current therapeutics are still inadequate, as a potential roadmap for continuing investigation. The possibility of faster and more complete clinical resolution by using NikZ has attracted scientific attention for decades. NikZ inhibits chitin structure formation, which is important for fungi, but not found in mammals. NikZ raised no safety concerns in a human Phase 1 trial or in extensive toxicology studies. NikZ showed strong clinical benefit in dogs with natural Coccidioides infection. NikZ has protected animals against fatal infections of Candida albicans. NikZ provides high protection in synergistic combination with several agent classes against Candida and Aspergillus species.
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Affiliation(s)
- David J. Larwood
- Valley Fever Solutions, Tucson, AZ 85719, USA; ; Tel.: +1-650-454-4126
- College of Pharmacy, University of Arizona, Tucson, AZ 85721, USA
- California Institute of Medical Research, San Jose, CA 95128, USA
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23
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Poester VR, Munhoz LS, Larwood D, Martinez M, Stevens DA, Xavier MO. Potential use of Nikkomycin Z as an anti- Sporothrix spp. drug. Med Mycol 2020; 59:345-349. [PMID: 32634218 DOI: 10.1093/mmy/myaa054] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/03/2020] [Accepted: 06/09/2020] [Indexed: 01/09/2023] Open
Abstract
Sporotrichosis, the most common subcutaneous mycosis in several countries, is caused by the dimorphic fungus, Sporothrix spp. Given some limitations in the treatment of this disease, and the high potential of nikkomycin Z (NikZ) as an antifungal against dimorphic fungi, this study aimed to evaluate the in vitro susceptibility of Sporothrix spp. to NikZ alone and with the drug of choice, itraconazole (ITZ). Seventeen clinical isolates of three Sporothrix spp. species (10 S. brasiliensis, six S. schenckii sensu stricto and one S. globosa) were tested in microdilution and checkerboard assays. Minimal inhibitory concentration (MIC), minimal fungicidal concentration (MFC), fractional inhibitory and fungicidal concentration indexes (FICi and FFCi) were analyzed. MIC of NikZ alone could be determined against S. globosa (12.5 μg/ml) and against 67% (4/6) and 30% (3/10) of the S. schenckii sensu stricto and S. brasiliensis isolates, respectively (≤ 400 μg/ml). Synergism with ITZ was showed against almost all the isolates tested (94%; 16/17), including reversing resistance to ITZ alone in some isolates. Our study shows the potential of NikZ in sporotrichosis treatment. Further studies in experimental models are needed to understand the possible future application of this drug as an alternative therapy or as an adjuvant in sporotrichosis treatment. LAY ABSTRACT Sporotrichosis is a subcutaneous and lymphatic infection, caused by fungi of Sporothrix spp. Our study shows the potential of NikZ to inhibiting Sporothrix species in vitro. Further studies are needed to understand the future application of this drug to sporotrichosis treatment.
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Affiliation(s)
- Vanice Rodrigues Poester
- Programa de Pós Graduação em Ciências da Saúde , Faculdade de Medicina (FAMED), Universidade Federal do Rio Grande (FURG), RS, Brazil
| | - Lívia Silveira Munhoz
- Programa de Pós Graduação em Ciências da Saúde , Faculdade de Medicina (FAMED), Universidade Federal do Rio Grande (FURG), RS, Brazil
| | - David Larwood
- Valley Fever Solutions, Tucson, Arizona, USA.,California Institute for Medical Research, San Jose, California, USA
| | - Marife Martinez
- California Institute for Medical Research, San Jose, California, USA
| | - David A Stevens
- California Institute for Medical Research, San Jose, California, USA.,Div. of Infectious Diseases and Geographic Medicine, Stanford University Medical School, Stanford, California, USA
| | - Melissa Orzechowski Xavier
- Programa de Pós Graduação em Ciências da Saúde , Faculdade de Medicina (FAMED), Universidade Federal do Rio Grande (FURG), RS, Brazil.,California Institute for Medical Research, San Jose, California, USA
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24
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Anti-Sporothrix activity of ibuprofen combined with antifungal. Braz J Microbiol 2020; 52:101-106. [PMID: 32617835 DOI: 10.1007/s42770-020-00327-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 06/25/2020] [Indexed: 10/23/2022] Open
Abstract
The in vitro activity of ibuprofen, a nonsteroidal anti-inflammatory drug, was evaluated against Sporothrix brasiliensis and S. schenckii, either alone or in combination with amphotericin B, itraconazole, or terbinafine. The inhibitory activity of ibuprofen as a single agent was determined according to minimum inhibitory concentration (MIC) values, while the effect of ibuprofen combined with amphotericin B, itraconazole, or terbinafine was estimated by microdilution checkerboard methodology. The ultrastructural alterations of S. schenckii after exposure to the combination of ibuprofen and amphotericin B were evaluated by scanning electron microscopy (SEM) and flow cytometry analysis. As a single agent, ibuprofen inhibited Sporothrix growth with a MIC median of 256 μg/mL, while the MIC medians of ibuprofen in combination with antifungals were 16 μg/mL and 128 μg/mL. The MIC values of amphotericin B, itraconazole, and terbinafine were reduced when isolates were co-incubated with ibuprofen, mainly the polyene. The major alteration after treatment with the ibuprofen/amphotericin B combination was the increase in the presence of filamentous forms and high membrane damage with loss of plasma membrane integrity. In summary, we demonstrated that ibuprofen increases the in vitro activity of antifungals, mainly amphotericin B, against S. brasiliensis and S. schenckii. Future in vivo studies exploring combination therapy with ibuprofen and antifungals in animal models are needed to confirm its efficacy.
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Rozada AM, Rodrigues-Vendramini FA, Gonçalves DS, Rosa FA, Basso EA, Seixas FA, Kioshima ÉS, Gauze GF. Synthesis and antifungal activity of new hybrids pyrimido[4,5-d]pyridazinone-N-acylhydrazones. Bioorg Med Chem Lett 2020; 30:127244. [DOI: 10.1016/j.bmcl.2020.127244] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 04/29/2020] [Accepted: 05/02/2020] [Indexed: 01/09/2023]
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Abstract
Aspergillus fumigatus is a saprotrophic fungus; its primary habitat is the soil. In its ecological niche, the fungus has learned how to adapt and proliferate in hostile environments. This capacity has helped the fungus to resist and survive against human host defenses and, further, to be responsible for one of the most devastating lung infections in terms of morbidity and mortality. In this review, we will provide (i) a description of the biological cycle of A. fumigatus; (ii) a historical perspective of the spectrum of aspergillus disease and the current epidemiological status of these infections; (iii) an analysis of the modes of immune response against Aspergillus in immunocompetent and immunocompromised patients; (iv) an understanding of the pathways responsible for fungal virulence and their host molecular targets, with a specific focus on the cell wall; (v) the current status of the diagnosis of different clinical syndromes; and (vi) an overview of the available antifungal armamentarium and the therapeutic strategies in the clinical context. In addition, the emergence of new concepts, such as nutritional immunity and the integration and rewiring of multiple fungal metabolic activities occurring during lung invasion, has helped us to redefine the opportunistic pathogenesis of A. fumigatus.
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Affiliation(s)
- Jean-Paul Latgé
- School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Georgios Chamilos
- School of Medicine, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion, Crete, Greece
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Alaraidh IA, Okla MK, Alamri SA, AL‐ghamdi AA, Soufan WH, Allam AA, Fouda MMG, Gaffer HE. Synthesis of Bis‐(2‐thiazolyl)amine Analogues and Evaluation of Their Antibacterial, Antioxidant and Cytotoxic Activities. ChemistrySelect 2019. [DOI: 10.1002/slct.201902272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Ibrahim A. Alaraidh
- Department of Botany and MicrobiologyCollege of ScienceKing Saud University, P.O. Box 2455 Riyadh 11451 Saudi Arabia
| | - Mohammad K. Okla
- Department of Botany and MicrobiologyCollege of ScienceKing Saud University, P.O. Box 2455 Riyadh 11451 Saudi Arabia
| | - Saudi A. Alamri
- Department of Botany and MicrobiologyCollege of ScienceKing Saud University, P.O. Box 2455 Riyadh 11451 Saudi Arabia
| | - Abdullah A. AL‐ghamdi
- Department of Botany and MicrobiologyCollege of ScienceKing Saud University, P.O. Box 2455 Riyadh 11451 Saudi Arabia
| | - Walid H. Soufan
- College of AgricultureKing Saud University P.O. Box 2455 Riyadh 11451 Saudia Arabia
| | - Ahmed A. Allam
- Department of ZoologyFaculty of ScienceBeni-Suef University Beni-Suef 65211 Egypt
| | - Moustafa M. G. Fouda
- Pretreatment and Finishing of Cellulosic-based Fibers DepartmentTextile Industries Research DivisionNational Research Centre 33 El-Buhouth Street, Dokki Cairo 12622 Egypt
| | - Hatem E. Gaffer
- DyeingPrinting and Auxiliaries DepartmentTextile Industries Research DivisionNational Research Centre 33 El-Buhouth Street, Dokki Cairo 12622 Egypt
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Arastehfar A, Wickes BL, Ilkit M, Pincus DH, Daneshnia F, Pan W, Fang W, Boekhout T. Identification of Mycoses in Developing Countries. J Fungi (Basel) 2019; 5:E90. [PMID: 31569472 PMCID: PMC6958481 DOI: 10.3390/jof5040090] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 09/22/2019] [Accepted: 09/26/2019] [Indexed: 12/12/2022] Open
Abstract
Extensive advances in technology offer a vast variety of diagnostic methods that save time and costs, but identification of fungal species causing human infections remains challenging in developing countries. Since the echinocandins, antifungals widely used to treat invasive mycoses, are still unavailable in developing countries where a considerable number of problematic fungal species are present, rapid and reliable identification is of paramount importance. Unaffordability, large footprints, lack of skilled personnel, and high costs associated with maintenance and infrastructure are the main factors precluding the establishment of high-precision technologies that can replace inexpensive yet time-consuming and inaccurate phenotypic methods. In addition, point-of-care lateral flow assay tests are available for the diagnosis of Aspergillus and Cryptococcus and are highly relevant for developing countries. An Aspergillus galactomannan lateral flow assay is also now available. Real-time PCR remains difficult to standardize and is not widespread in countries with limited resources. Isothermal and conventional PCR-based amplification assays may be alternative solutions. The combination of real-time PCR and serological assays can significantly increase diagnostic efficiency. However, this approach is too expensive for medical institutions in developing countries. Further advances in next-generation sequencing and other innovative technologies such as clustered regularly interspaced short palindromic repeats (CRISPR)-based diagnostic tools may lead to efficient, alternate methods that can be used in point-of-care assays, which may supplement or replace some of the current technologies and improve the diagnostics of fungal infections in developing countries.
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Affiliation(s)
- Amir Arastehfar
- Westerdijk Fungal Biodiversity Institute, 3584 CT Utrecht, The Netherlands.
| | - Brian L Wickes
- The Department of Microbiology, Immunology, and Molecular Genetics, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
| | - Macit Ilkit
- Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana 01330, Turkey.
| | | | - Farnaz Daneshnia
- Westerdijk Fungal Biodiversity Institute, 3584 CT Utrecht, The Netherlands.
| | - Weihua Pan
- Department of Dermatology, Shanghai Key Laboratory of Molecular Medical Mycology, Shanghai Institute of Medical Mycology, Second Military Medical University, Shanghai 200003, China.
| | - Wenjie Fang
- Department of Dermatology, Shanghai Key Laboratory of Molecular Medical Mycology, Shanghai Institute of Medical Mycology, Second Military Medical University, Shanghai 200003, China.
| | - Teun Boekhout
- Westerdijk Fungal Biodiversity Institute, 3584 CT Utrecht, The Netherlands.
- Department of Dermatology, Shanghai Key Laboratory of Molecular Medical Mycology, Shanghai Institute of Medical Mycology, Second Military Medical University, Shanghai 200003, China.
- Institute of Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1012 WX Amsterdam, The Netherlands.
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Prusty JS, Kumar A. Coumarins: antifungal effectiveness and future therapeutic scope. Mol Divers 2019; 24:1367-1383. [PMID: 31520360 DOI: 10.1007/s11030-019-09992-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/03/2019] [Indexed: 02/07/2023]
Abstract
The antifungals that are in current clinical practice have a high occurrence of a side effect and multidrug resistance (MDR). Researchers across the globe are trying to develop a suitable antifungal that has minimum side effect as well as no MDR issues. Due to serious undesired effects connected with individual antifungals, it is now necessary to introduce novel and effective drugs having numerous potentials to regulate complex therapeutic targets of several fungal infections simultaneously. Thus, by taking a lead from this subject, synthesis of potent antifungals from coumarin moiety could contribute to the development of promising antifungal. Its resemblance and structural diversity make it possible to produce an auspicious antifungal candidate. Due to the natural origin of coumarin, its presence in diversity, and their broad spectrum of pharmacological activities, it secures an important place for the researcher to investigate and develop it as a promising antifungal in future. This manuscript discusses the bioavailability of coumarin (natural secondary metabolic molecule) that has privileged scaffold for many mycologists to develop it as a broad-spectrum antifungal against several opportunistic mycoses. As a result, several different kinds of coumarin derivatives were synthesized and their antifungal properties were evaluated. This review compiles various coumarin derivatives broadly investigated for antifungal activities to understand its current status and future therapeutic scope in antifungal therapy.
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Affiliation(s)
- Jyoti Sankar Prusty
- Department of Biotechnology, National Institute of Technology, Raipur, CG, 492010, India
| | - Awanish Kumar
- Department of Biotechnology, National Institute of Technology, Raipur, CG, 492010, India.
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Abstract
Chronic laryngitis is an inflammatory process of at least 3 weeks duration and affects phonation, breathing, and swallowing. This article describes the infectious, inflammatory, and autoimmune causes of chronic laryngitis. Symptoms of chronic laryngitis are nonspecific and may range from mild to airway compromise requiring emergent tracheostomy.
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Vaccine Development to Systemic Mycoses by Thermally Dimorphic Fungi. CURRENT TROPICAL MEDICINE REPORTS 2019. [DOI: 10.1007/s40475-019-00179-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Affiliation(s)
- Damian J Krysan
- a Department of Pediatrics and Microbiology/Immunology , University of Rochester School of Medicine and Dentistry , Rochester , NY , USA
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Brilhante RSN, Guedes GMDM, Silva MLQD, Castelo-Branco DSCM, Cordeiro RDA, Sidrim JJC, Rocha MFG. A proposal for antifungal epidemiological cut-off values against Histoplasma capsulatum var. capsulatum based on the susceptibility of isolates from HIV-infected patients with disseminated histoplasmosis in Northeast Brazil. Int J Antimicrob Agents 2018; 52:272-277. [PMID: 29592837 DOI: 10.1016/j.ijantimicag.2018.03.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/12/2018] [Accepted: 03/21/2018] [Indexed: 10/17/2022]
Abstract
Epidemiological cut-off values (ECVs) have been used as a tool to detect the acquisition of resistance mechanisms to antifungal drugs. In this context, the objective of this study was to determine the ECVs for classic antifungals against Histoplasma capsulatum var. capsulatum isolates from human immunodeficiency virus (HIV)-infected patients with a diagnosis of disseminated histoplasmosis. First, minimum inhibitory concentrations (MICs) for amphotericin B (AmB), itraconazole (ITR), fluconazole (FLU), voriconazole (VCZ) and caspofungin (CAS) were determined against 138 H. capsulatum isolates in the filamentous form by the broth microdilution method; antifungal ECVs were then calculated. MIC ranges were 0.0078-1 µg/mL for AmB, 0.0005-0.0625 µg/mL for ITR, 2 to ≥256 µg/mL for FLU, 0.0078-1 µg/mL for VCZ and ≤0.0156 to ≥32 µg/mL for CAS. The obtained ECVs were 0.5, 0.0313, 128, 0.5 and 16 µg/mL for AmB, ITR, FLU, VCZ and CAS, respectively. The percentage of wild-type isolates was 96.4% for AmB, 98.6% for ITR and 99.3% for FLU, VCZ and CAS. Although these results do not cover all phylogenetic species of H. capsulatum, they bring important information on strains from Brazil. In addition, the assessed isolates were from HIV-positive patients, which may not reflect the antifungal ECVs against isolates from immunocompetent individuals or from other sources. Finally, this study pioneers the initiative of establishing ECVs for five antifungal agents against H. capsulatum var. capsulatum, providing a criterion for the interpretation of susceptibility results as well as a monitoring strategy for the emergence of antifungal resistance.
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Affiliation(s)
- Raimunda Sâmia Nogueira Brilhante
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil.
| | - Glaucia Morgana de Melo Guedes
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Maria Lucilene Queiroz da Silva
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Débora Souza Collares Maia Castelo-Branco
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Rossana de Aguiar Cordeiro
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - José Júlio Costa Sidrim
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Marcos Fábio Gadelha Rocha
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil; College of Veterinary Medicine, Postgraduate Program in Veterinary Sciences, State University of Ceará, Fortaleza, Ceará, Brazil
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Antifungal Resistance, Metabolic Routes as Drug Targets, and New Antifungal Agents: An Overview about Endemic Dimorphic Fungi. Mediators Inflamm 2017; 2017:9870679. [PMID: 28694566 PMCID: PMC5485324 DOI: 10.1155/2017/9870679] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 04/28/2017] [Accepted: 05/23/2017] [Indexed: 12/30/2022] Open
Abstract
Diseases caused by fungi can occur in healthy people, but immunocompromised patients are the major risk group for invasive fungal infections. Cases of fungal resistance and the difficulty of treatment make fungal infections a public health problem. This review explores mechanisms used by fungi to promote fungal resistance, such as the mutation or overexpression of drug targets, efflux and degradation systems, and pleiotropic drug responses. Alternative novel drug targets have been investigated; these include metabolic routes used by fungi during infection, such as trehalose and amino acid metabolism and mitochondrial proteins. An overview of new antifungal agents, including nanostructured antifungals, as well as of repositioning approaches is discussed. Studies focusing on the development of vaccines against antifungal diseases have increased in recent years, as these strategies can be applied in combination with antifungal therapy to prevent posttreatment sequelae. Studies focused on the development of a pan-fungal vaccine and antifungal drugs can improve the treatment of immunocompromised patients and reduce treatment costs.
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Maphanga TG, Britz E, Zulu TG, Mpembe RS, Naicker SD, Schwartz IS, Govender NP. In Vitro Antifungal Susceptibility of Yeast and Mold Phases of Isolates of Dimorphic Fungal Pathogen Emergomyces africanus (Formerly Emmonsia sp.) from HIV-Infected South African Patients. J Clin Microbiol 2017; 55:1812-1820. [PMID: 28356416 PMCID: PMC5442537 DOI: 10.1128/jcm.02524-16] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/20/2017] [Indexed: 11/20/2022] Open
Abstract
Disseminated emmonsiosis is an important AIDS-related mycosis in South Africa that is caused by Emergomycesafricanus, a newly described and renamed dimorphic fungal pathogen. In vitro antifungal susceptibility data can guide management. Identification of invasive clinical isolates was confirmed phenotypically and by sequencing of the internal transcribed spacer region. Yeast and mold phase MICs of fluconazole, voriconazole, itraconazole, posaconazole, caspofungin, anidulafungin, micafungin, and flucytosine were determined with custom-made frozen broth microdilution (BMD) panels in accordance with Clinical and Laboratory Standards Institute recommendations. MICs of amphotericin B, itraconazole, posaconazole, and voriconazole were determined by Etest. Fifty unique E. africanus isolates were tested. The yeast and mold phase geometric mean (GM) BMD and Etest MICs of itraconazole were 0.01 mg/liter. The voriconazole and posaconazole GM BMD MICs were 0.01 mg/liter for both phases, while the GM Etest MICs were 0.001 and 0.002 mg/liter, respectively. The fluconazole GM BMD MICs were 0.18 mg/liter for both phases. The GM Etest MICs of amphotericin B, for the yeast and mold phases were 0.03 and 0.01 mg/liter. The echinocandins and flucytosine had very limited in vitro activity. Treatment and outcome data were available for 37 patients; in a multivariable model including MIC data, only isolation from blood (odds ratio [OR], 8.6; 95% confidence interval [CI], 1.3 to 54.4; P = 0.02) or bone marrow (OR, 12.1; 95% CI, 1.2 to 120.2; P = 0.03) (versus skin biopsy) was associated with death. In vitro susceptibility data support the management of disseminated emmonsiosis with amphotericin B, followed by itraconazole, voriconazole, or posaconazole. Fluconazole was a relatively less potent agent.
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Affiliation(s)
- Tsidiso G Maphanga
- National Institute for Communicable Diseases (Centre for Healthcare-Associated Infections, Antimicrobial Resistance and Mycoses), a Division of the National Health Laboratory Service, Johannesburg, South Africa
- Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Erika Britz
- National Institute for Communicable Diseases (Centre for Healthcare-Associated Infections, Antimicrobial Resistance and Mycoses), a Division of the National Health Laboratory Service, Johannesburg, South Africa
| | - Thokozile G Zulu
- National Institute for Communicable Diseases (Centre for Healthcare-Associated Infections, Antimicrobial Resistance and Mycoses), a Division of the National Health Laboratory Service, Johannesburg, South Africa
| | - Ruth S Mpembe
- National Institute for Communicable Diseases (Centre for Healthcare-Associated Infections, Antimicrobial Resistance and Mycoses), a Division of the National Health Laboratory Service, Johannesburg, South Africa
| | - Serisha D Naicker
- National Institute for Communicable Diseases (Centre for Healthcare-Associated Infections, Antimicrobial Resistance and Mycoses), a Division of the National Health Laboratory Service, Johannesburg, South Africa
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Ilan S Schwartz
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Nelesh P Govender
- National Institute for Communicable Diseases (Centre for Healthcare-Associated Infections, Antimicrobial Resistance and Mycoses), a Division of the National Health Laboratory Service, Johannesburg, South Africa
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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Travassos LR, Taborda CP. Linear Epitopes of Paracoccidioides brasiliensis and Other Fungal Agents of Human Systemic Mycoses As Vaccine Candidates. Front Immunol 2017; 8:224. [PMID: 28344577 PMCID: PMC5344917 DOI: 10.3389/fimmu.2017.00224] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/16/2017] [Indexed: 12/19/2022] Open
Abstract
Dimorphic fungi are agents of systemic mycoses associated with significant morbidity and frequent lethality in the Americas. Among the pathogenic species are Paracoccidioides brasiliensis and Paracoccidioides lutzii, which predominate in South America; Histoplasma capsulatum, Coccidioides posadasii, and Coccidioides immitis, and the Sporothrix spp. complex are other important pathogens. Associated with dimorphic fungi other important infections are caused by yeast such as Candida spp. and Cryptococcus spp. or mold such as Aspergillus spp., which are also fungal agents of deadly infections. Nowadays, the actual tendency of therapy is the development of a pan-fungal vaccine. This is, however, not easy because of the complexity of eukaryotic cells and the particularities of different species and isolates. Albeit there are several experimental vaccines being studied, we will focus mainly on peptide vaccines or epitopes of T-cell receptors inducing protective fungal responses. These peptides can be carried by antibody inducing β-(1,3)-glucan oligo or polysaccharides, or be mixed with them for administration. The present review discusses the efficacy of linear peptide epitopes in the context of antifungal immunization and vaccine proposition.
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Affiliation(s)
- Luiz R Travassos
- Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo , São Paulo , Brazil
| | - Carlos P Taborda
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Laboratory of Medical Mycology IMTSP/LIM53/HCFMUSP, University of São Paulo, São Paulo, Brazil
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Souza ACO, Amaral AC. Antifungal Therapy for Systemic Mycosis and the Nanobiotechnology Era: Improving Efficacy, Biodistribution and Toxicity. Front Microbiol 2017; 8:336. [PMID: 28326065 PMCID: PMC5340099 DOI: 10.3389/fmicb.2017.00336] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 02/17/2017] [Indexed: 01/11/2023] Open
Abstract
Fungal diseases have been emerging as an important public health problem worldwide with the increase in host predisposition factors due to immunological dysregulations, immunosuppressive and/or anticancer therapy. Antifungal therapy for systemic mycosis is limited, most of times expensive and causes important toxic effects. Nanotechnology has become an interesting strategy to improve efficacy of traditional antifungal drugs, which allows lower toxicity, better biodistribution, and drug targeting, with promising results in vitro and in vivo. In this review, we provide a discussion about conventional antifungal and nanoantifungal therapies for systemic mycosis.
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Affiliation(s)
- Ana C. O. Souza
- Laboratory of Pathogenic Dimorphic Fungi, Institute of Biomedical Sciences, University of São PauloSão Paulo, Brazil
| | - Andre C. Amaral
- Laboratory of Nano and Biotechnology, Institute of Tropical Pathology and Public Health, Federal University of GoiásGoiânia, Brazil
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