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Oliveira-Brito PKM, de Campos GY, Guimarães JG, Serafim da Costa L, Silva de Moura E, Lazo-Chica JE, Roque-Barreira MC, da Silva TA. Adjuvant Curdlan Contributes to Immunization against Cryptococcus gattii Infection in a Mouse Strain-Specific Manner. Vaccines (Basel) 2022; 10:vaccines10040620. [PMID: 35455369 PMCID: PMC9030172 DOI: 10.3390/vaccines10040620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/05/2022] [Accepted: 04/07/2022] [Indexed: 02/06/2023] Open
Abstract
The low efficacy and side effects associated with antifungal agents have highlighted the importance of developing immunotherapeutic approaches to treat Cryptococcus gattii infection. We developed an immunization strategy that uses selective Dectin-1 agonist as an adjuvant. BALB/c or C57BL/6 mice received curdlan or β-glucan peptide (BGP) before immunization with heat-killed C. gattii, and the mice were infected with viable C. gattii on day 14 post immunization and euthanized 14 days after infection. Adjuvant curdlan restored pulmonary tumor necrosis factor- α (TNF-α) levels, as induced by immunization with heat-killed C. gattii. The average area and relative frequency of C. gattii titan cells in the lungs of curdlan-treated BALB/c mice were reduced. However, this did not reduce the pulmonary fungal burden or decrease the i0,nflammatory infiltrate in the pulmonary parenchyma of BALB/c mice. Conversely, adjuvant curdlan induced high levels of interferon-γ (IFN-γ) and interleukin (IL)-10 and decreased the C. gattii burden in the lungs of C57BL/6 mice, which was not replicated in β-glucan peptide-treated mice. The adjuvant curdlan favors the control of C. gattii infection depending on the immune response profile of the mouse strain. This study will have implications for developing new immunotherapeutic approaches to treat C. gattii infection.
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Affiliation(s)
- Patrícia Kellen Martins Oliveira-Brito
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Gabriela Yamazaki de Campos
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Júlia Garcia Guimarães
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Letícia Serafim da Costa
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 14049-900, SP, Brazil;
| | - Edanielle Silva de Moura
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Javier Emílio Lazo-Chica
- Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba 38025-189, MG, Brazil;
| | - Maria Cristina Roque-Barreira
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
| | - Thiago Aparecido da Silva
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (P.K.M.O.-B.); (G.Y.d.C.); (J.G.G.); (E.S.d.M.); (M.C.R.-B.)
- Thiago Aparecido da Silva, Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto 14049-900, SP, Brazil
- Correspondence: or ; Tel.: +55-16-3315-3049
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Liposomal Ellagic Acid Alleviates Cyclophosphamide-Induced Toxicity and Eliminates the Systemic Cryptococcus neoformans Infection in Leukopenic Mice. Pharmaceutics 2021; 13:pharmaceutics13060882. [PMID: 34203688 PMCID: PMC8232310 DOI: 10.3390/pharmaceutics13060882] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/01/2021] [Accepted: 06/07/2021] [Indexed: 11/21/2022] Open
Abstract
Cryptococcus neoformans infections rose sharply due to rapid increase in the numbers of immunocompromised individuals in recent years. Treatment of Cryptococcosis in immunocompromised persons is largely very challenging and hopeless. Hence, this study aimed to determine the activity of ellagic acid (EA) in the treatment of C. neoformans in cyclophosphamide injected leukopenic mice. A liposomal formulation of ellagic acid (Lip-EA) was prepared and characterized, and its antifungal activity was assessed in comparison to fluconazole (FLZ). The efficacy of the drug treatment was tested by assessing survival rate, fungal burden, and histological analysis in lung tissues. The safety of the drug formulations was tested by investigating hepatic, renal function, and antioxidant levels. The results of the present work demonstrated that Lip-EA, not FLZ, effectively eliminated C. neoformans infection in the leukopenic mice. Mice treated with Lip-EA (40 mg/kg) showed 70% survival rate and highly reduced fungal burden in their lung tissues, whereas the mice treated with FLZ (40 mg/kg) had 20% survival rate and greater fungal load in their lungs. Noteworthy, Lip-EA treatment alleviated cyclophosphamide-induced toxicity and restored hepatic and renal function parameters. Moreover, Lip-EA treatment restored the levels of superoxide dismutase and reduced glutathione and catalase in the lung tissues. The effect of FLZ or EA or Lip-EA against C. neoformans infection was assessed by the histological analysis of lung tissues. Lip-EA effectively reduced influx of inflammatory cells, thickening of alveolar walls, congestion, and hemorrhage. The findings of the present study suggest that Lip-EA may prove to be a promising therapeutic formulation against C. neoformans in immunocompromised persons.
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Stempinski PR, Zielinski JM, Dbouk NH, Huey ES, McCormack EC, Rubin AM, Chandrasekaran S, Kozubowski L. Genetic contribution to high temperature tolerance in Cryptococcus neoformans. Genetics 2021; 217:1-15. [PMID: 33683363 PMCID: PMC8045695 DOI: 10.1093/genetics/iyaa009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 10/24/2020] [Indexed: 11/12/2022] Open
Abstract
The human fungal pathogen Cryptococcus neoformans relies on a complex signaling network for the adaptation and survival at the host temperature. Protein phosphatase calcineurin is central to proliferation at 37°C but its exact contributions remain ill-defined. To better define genetic contributions to the C. neoformans temperature tolerance, 4031 gene knockouts were screened for genes essential at 37°C and under conditions that keep calcineurin inactive. Identified 83 candidate strains, potentially sensitive to 37°C, were subsequently subject to technologically simple yet robust assay, in which cells are exposed to a temperature gradient. This has resulted in identification of 46 genes contributing to the maximum temperature at which C. neoformans can proliferate (Tmax). The 46 mutants, characterized by a range of Tmax on drug-free media, were further assessed for Tmax under conditions that inhibit calcineurin, which led to identification of several previously uncharacterized knockouts exhibiting synthetic interaction with the inhibition of calcineurin. A mutant that lacked septin Cdc11 was among those with the lowest Tmax and failed to proliferate in the absence of calcineurin activity. To further define connections with calcineurin and the role for septins in high temperature growth, the 46 mutants were tested for cell morphology at 37°C and growth in the presence of agents disrupting cell wall and cell membrane. Mutants sensitive to calcineurin inhibition were tested for synthetic lethal interaction with deletion of the septin-encoding CDC12 and the localization of the septin Cdc3-mCherry. The analysis described here pointed to previously uncharacterized genes that were missed in standard growth assays indicating that the temperature gradient assay is a valuable complementary tool for elucidating the genetic basis of temperature range at which microorganisms proliferate.
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Affiliation(s)
- Piotr R Stempinski
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Jessica M Zielinski
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Nadir H Dbouk
- Department of Biology, Furman University, Greenville, SC 29613, USA
| | - Elizabeth S Huey
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Ellen C McCormack
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | - Alexander M Rubin
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
| | | | - Lukasz Kozubowski
- Department of Genetics & Biochemistry, Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, SC 29634, USA
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Sharma D, Bisht GS. Recent Updates on Antifungal Peptides. Mini Rev Med Chem 2020; 20:260-268. [PMID: 31556857 DOI: 10.2174/1389557519666190926112423] [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: 05/21/2018] [Revised: 07/17/2018] [Accepted: 09/06/2019] [Indexed: 12/11/2022]
Abstract
The current trend of increment in the frequency of antifungal resistance has brought research into an era where new antifungal compounds with novel mechanisms of action are required. Natural antimicrobial peptides, which are ubiquitous components of innate immunity, represent their candidature for novel antifungal peptides. Various antifungal peptides have been isolated from different species ranging from small marine organisms to insects and from various other living species. Based on these peptides, various mimetics of antifungal peptides have also been synthesized using non-natural amino acids. Utilization of these antifungal peptides is somehow limited due to their toxic and unstable nature. This review discusses recent updates and future directions of antifungal peptides, for taking them to the shelf from the bench.
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Affiliation(s)
- Deepika Sharma
- Department of Pharmacy, Jaypee University of Information Technology, Waknaghat, Solan, Himachal Pradesh, 173234, India
| | - Gopal Singh Bisht
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat, Solan, Himachal Pradesh, 173234, India
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Bermas A, Geddes‐McAlister J. Combatting the evolution of antifungal resistance in
Cryptococcus neoformans. Mol Microbiol 2020; 114:721-734. [DOI: 10.1111/mmi.14565] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 06/09/2020] [Accepted: 06/22/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Arianne Bermas
- Department of Molecular and Cellular Biology University of Guelph Guelph ON Canada
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6
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Polysaccharide diversity in VNI isolates of Cryptococcus neoformans from Roraima, Northern Brazil. Fungal Biol 2019; 123:699-708. [DOI: 10.1016/j.funbio.2019.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 06/03/2019] [Accepted: 06/03/2019] [Indexed: 02/03/2023]
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The regulation of the sulfur amino acid biosynthetic pathway in Cryptococcus neoformans: the relationship of Cys3, Calcineurin, and Gpp2 phosphatases. Sci Rep 2019; 9:11923. [PMID: 31417135 PMCID: PMC6695392 DOI: 10.1038/s41598-019-48433-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 08/01/2019] [Indexed: 01/02/2023] Open
Abstract
Cryptococcosis is a fungal disease caused by C. neoformans. To adapt and survive in diverse ecological niches, including the animal host, this opportunistic pathogen relies on its ability to uptake nutrients, such as carbon, nitrogen, iron, phosphate, sulfur, and amino acids. Genetic circuits play a role in the response to environmental changes, modulating gene expression and adjusting the microbial metabolism to the nutrients available for the best energy usage and survival. We studied the sulfur amino acid biosynthesis and its implications on C. neoformans biology and virulence. CNAG_04798 encodes a BZip protein and was annotated as CYS3, which has been considered an essential gene. However, we demonstrated that CYS3 is not essential, in fact, its knockout led to sulfur amino acids auxotroph. Western blots and fluorescence microscopy indicated that GFP-Cys3, which is expressed from a constitutive promoter, localizes to the nucleus in rich medium (YEPD); the addition of methionine and cysteine as sole nitrogen source (SD-N + Met/Cys) led to reduced nuclear localization and protein degradation. By proteomics, we identified and confirmed physical interaction among Gpp2, Cna1, Cnb1 and GFP-Cys3. Deletion of the calcineurin and GPP2 genes in a GFP-Cys3 background demonstrated that calcineurin is required to maintain Cys3 high protein levels in YEPD and that deletion of GPP2 causes GFP-Cys3 to persist in the presence of sulfur amino acids. Global transcriptional profile of mutant and wild type by RNAseq revealed that Cys3 controls all branches of the sulfur amino acid biosynthesis, and sulfur starvation leads to induction of several amino acid biosynthetic routes. In addition, we found that Cys3 is required for virulence in Galleria mellonella animal model.
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8
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Gerstein AC, Jackson KM, McDonald TR, Wang Y, Lueck BD, Bohjanen S, Smith KD, Akampurira A, Meya DB, Xue C, Boulware DR, Nielsen K. Identification of Pathogen Genomic Differences That Impact Human Immune Response and Disease during Cryptococcus neoformans Infection. mBio 2019; 10:e01440-19. [PMID: 31311883 PMCID: PMC6635531 DOI: 10.1128/mbio.01440-19] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 06/10/2019] [Indexed: 12/18/2022] Open
Abstract
Patient outcomes during infection are due to a complex interplay between the quality of medical care, host immunity factors, and the infecting pathogen's characteristics. To probe the influence of pathogen genotype on human survival, immune response, and other parameters of disease, we examined Cryptococcus neoformans isolates collected during the Cryptococcal Optimal Antiretroviral Therapy (ART) Timing (COAT) Trial in Uganda. We measured human participants' survival, meningitis disease parameters, immunologic phenotypes, and pathogen in vitro growth characteristics. We compared those clinical data to whole-genome sequences from 38 C. neoformans isolates of the most frequently observed sequence type (ST), ST93, in our Ugandan participant population and to sequences from an additional 18 strains of 9 other sequence types representing the known genetic diversity within the Ugandan Cryptococcus clinical isolates. We focused our analyses on 652 polymorphisms that were variable among the ST93 genomes, were not in centromeres or extreme telomeres, and were predicted to have a fitness effect. Logistic regression and principal component analysis identified 40 candidate Cryptococcus genes and 3 hypothetical RNAs associated with human survival, immunologic response, or clinical parameters. We infected mice with 17 available KN99α gene deletion strains for these candidate genes and found that 35% (6/17) directly influenced murine survival. Four of the six gene deletions that impacted murine survival were novel. Such bedside-to-bench translational research identifies important candidate genes for future studies on virulence-associated traits in human Cryptococcus infections.IMPORTANCE Even with the best available care, mortality rates in cryptococcal meningitis range from 20% to 60%. Disease is often due to infection by the fungus Cryptococcus neoformans and involves a complex interaction between the human host and the fungal pathogen. Although previous studies have suggested genetic differences in the pathogen impact human disease, it has proven quite difficult to identify the specific C. neoformans genes that impact the outcome of the human infection. Here, we take advantage of a Ugandan patient cohort infected with closely related C. neoformans strains to examine the role of pathogen genetic variants on several human disease characteristics. Using a pathogen whole-genome sequencing approach, we showed that 40 C. neoformans genes are associated with human disease. Surprisingly, many of these genes are specific to Cryptococcus and have unknown functions. We also show deletion of some of these genes alters disease in a mouse model of infection, confirming their role in disease. These findings are particularly important because they are the first to identify C. neoformans genes associated with human cryptococcal meningitis and lay the foundation for future studies that may lead to new treatment strategies aimed at reducing patient mortality.
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Affiliation(s)
- Aleeza C Gerstein
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Katrina M Jackson
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Tami R McDonald
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Yina Wang
- Public Health Research Institute, Rutgers University, Newark, New Jersey, USA
| | - Benjamin D Lueck
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Sara Bohjanen
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Kyle D Smith
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Andrew Akampurira
- Infectious Diseases Institute and School of Medicine, College of Health Sciences, Makerere University, Kampala, Uganda
| | - David B Meya
- Infectious Diseases Institute and School of Medicine, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Chaoyang Xue
- Public Health Research Institute, Rutgers University, Newark, New Jersey, USA
| | - David R Boulware
- Department of Medicine, University of Minnesota, Minneapolis, Minnesota, USA
| | - Kirsten Nielsen
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
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Ni S, Li B, Xu Y, Mao F, Li X, Lan L, Zhu J, Li J. Targeting virulence factors as an antimicrobial approach: Pigment inhibitors. Med Res Rev 2019; 40:293-338. [PMID: 31267561 DOI: 10.1002/med.21621] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/30/2019] [Accepted: 06/13/2019] [Indexed: 12/19/2022]
Abstract
The fascinating and dangerous colored pathogens contain unique chemically pigmented molecules, which give varied and efficient assistance as virulence factors to the crucial reproduction and growth of microbes. Therefore, multiple novel strategies and inhibitors have been developed in recent years that target virulence factor pigments. However, despite the importance and significance of this topic, it has not yet been comprehensively reviewed. Moreover, research groups around the world have made successful progress against antibacterial infections by targeting pigment production, including our serial works on the discovery of CrtN inhibitors against staphyloxanthin production in Staphylococcus aureus. On the basis of the previous achievements and recent progress of our group in this field, this article will be the first comprehensive review of pigment inhibitors against colored pathogens, especially S. aureus infections, and this article includes design strategies, representative case studies, advantages, limitations, and perspectives to guide future research.
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Affiliation(s)
- Shuaishuai Ni
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Baoli Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Yixiang Xu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Fei Mao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Xiaokang Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Lefu Lan
- State Key Laboratory of Drug Research, Shanghai Institute of Material Medical, Chinese Academy of Sciences, Shanghai, China
| | - Jin Zhu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Jian Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.,Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
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10
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Samie S, Trollope KM, Joubert LM, Makunga NP, Volschenk H. The antifungal and Cryptococcus neoformans virulence attenuating activity of Pelargonium sidoides extracts. JOURNAL OF ETHNOPHARMACOLOGY 2019; 235:122-132. [PMID: 30738119 DOI: 10.1016/j.jep.2019.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/18/2019] [Accepted: 02/05/2019] [Indexed: 06/09/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Limitations of clinical antifungal treatments and drug-resistance are drivers of the search for novel antifungal strategies. Extracts prepared from the tubers of the medicinal plant, Pelargonium sidoides, are known for their antiviral and antibacterial activities and are used in ethnomedicine for the treatment of acute respiratory infections. Their impact on fungi has not been well characterised. Here, we provide a first report on the antifungal activity of a P. sidoides aerial tissue extract against Cryptococcus neoformans as well as the effects of both tuber and aerial tissue extracts on selected virulence factors. AIM OF THE STUDY Novel antimicrobial strategies that target multiple cellular pathways or make use of anti-pathogenic compounds that inhibit virulence factors have been proposed. This work aimed to evaluate P. sidoides plant parts for their anticryptococcal activity and antipathogenic properties on selected virulence factors. MATERIALS AND METHODS The antifungal activity of crude P. sidoides tuber and aerial tissue extracts (15% m/m ethanol) were compared using a modified colourimetric antifungal susceptibility test. Fungicidal activity of the extracts was confirmed by plate counts. To test yeast resistance to the extracts, it was conditioned by multiple passages in sub-lethal doses followed by antifungal susceptibility testing. Cytotoxicity of the extracts was tested with a blood agar haemolysis assay. Extracts were evaluated for the presence of multiple bioactive compounds by solid-phase fractionation and visualisation by thin-layer chromatography in combination with bioassays. The influence of extracts on the production of the polysaccharide capsule, ergosterol content as well as laccase and urease activities were also evaluated. Cell surface variations after extract exposure were visualised by scanning electron microscopy (SEM). RESULTS Both tuber and aerial tissue extracts were fungicidal and contained multiple bioactive compounds which constrained the development of antifungal resistance. No haemolytic activity was observed, and the extracts did not appear to target ergosterol biosynthesis. However, the extracts displayed anti-pathogenic potential by significantly inhibiting laccase and urease activity while also significantly reducing capsule size. SEM revealed notable cell surface variations and provided support for the observed reduction in capsule size. CONCLUSIONS Our results provide support to the exploration of medicinal plants as sources of alternative antifungal therapies and the potential use of multicomponent inhibition and or virulence attenuation for next-generation treatment strategies. Our data also provide relevant information that may support the further use of P. sidoides in traditional medicines as well as in commercialised phytopharmaceuticals.
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Affiliation(s)
- Shakier Samie
- Department of Microbiology, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
| | - Kim M Trollope
- Department of Microbiology, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
| | - Lydia-Marié Joubert
- Department of Microbiology, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa; Central Analytical Facility, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
| | - Nokwanda P Makunga
- Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
| | - Heinrich Volschenk
- Department of Microbiology, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
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The Spectrum of Interactions between Cryptococcus neoformans and Bacteria. J Fungi (Basel) 2019; 5:jof5020031. [PMID: 31013706 PMCID: PMC6617360 DOI: 10.3390/jof5020031] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 04/08/2019] [Accepted: 04/11/2019] [Indexed: 01/08/2023] Open
Abstract
Cryptococcus neoformans is a major fungal pathogen that infects immunocompromised people and causes life-threatening meningoencephalitis. C. neoformans does not occur in isolation either in the environment or in the human host, but is surrounded by other microorganisms. Bacteria are ubiquitously distributed in nature, including soil, and make up the dominant part of the human microbiota. Pioneering studies in the 1950s demonstrated antifungal activity of environmental bacteria against C. neoformans. However, the mechanisms and implications of these interactions remain largely unknown. Recently, interest in polymicrobial interaction studies has been reignited by the development of improved sequencing methodologies, and by the realization that such interactions may have a huge impact on ecology and human health. In this review, we summarize our current understanding of the interaction of bacteria with C. neoformans.
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12
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Zimbres ACG, Reuwsaat JCV, Barcellos VA, Joffe LS, Fonseca FL, Staats CC, Schrank A, Kmetzsch L, Vainstein MH, Rodrigues ML. Pharmacological inhibition of pigmentation inCryptococcus. FEMS Yeast Res 2018; 19:5173039. [DOI: 10.1093/femsyr/foy119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 11/06/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Ana Claudia G Zimbres
- Centro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz, Rio de Janeiro 21941-902, Brazil
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Julia C V Reuwsaat
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
| | - Vanessa A Barcellos
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
| | - Luna S Joffe
- Centro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz, Rio de Janeiro 21941-902, Brazil
| | - Fernanda L Fonseca
- Centro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz, Rio de Janeiro 21941-902, Brazil
| | - Charley C Staats
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
- Departamento de Biologia Molecular e Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
| | - Augusto Schrank
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
- Departamento de Biologia Molecular e Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
| | - Livia Kmetzsch
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
- Departamento de Biologia Molecular e Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
| | - Marilene H Vainstein
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
- Departamento de Biologia Molecular e Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre 90040-060, Brazil
| | - Marcio L Rodrigues
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Laboratory of Gene Expression Regulation (LabReg), Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, PR 81310-020, Brazil
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Abstract
This Special Issue is designed to highlight the latest research and development on new antifungal compounds with mechanisms of action different from the ones of polyenes, azoles, and echinocandins. The papers presented here highlight new pathways and targets that could be exploited for the future development of new antifungal agents to be used alone or in combination with existing antifungals. A computational model for better predicting antifungal drug resistance is also presented.
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