1
|
Bras G, Satala D, Juszczak M, Kulig K, Wronowska E, Bednarek A, Zawrotniak M, Rapala-Kozik M, Karkowska-Kuleta J. Secreted Aspartic Proteinases: Key Factors in Candida Infections and Host-Pathogen Interactions. Int J Mol Sci 2024; 25:4775. [PMID: 38731993 PMCID: PMC11084781 DOI: 10.3390/ijms25094775] [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: 03/15/2024] [Revised: 04/19/2024] [Accepted: 04/25/2024] [Indexed: 05/13/2024] Open
Abstract
Extracellular proteases are key factors contributing to the virulence of pathogenic fungi from the genus Candida. Their proteolytic activities are crucial for extracting nutrients from the external environment, degrading host defenses, and destabilizing the internal balance of the human organism. Currently, the enzymes most frequently described in this context are secreted aspartic proteases (Saps). This review comprehensively explores the multifaceted roles of Saps, highlighting their importance in biofilm formation, tissue invasion through the degradation of extracellular matrix proteins and components of the coagulation cascade, modulation of host immune responses via impairment of neutrophil and monocyte/macrophage functions, and their contribution to antifungal resistance. Additionally, the diagnostic challenges associated with Candida infections and the potential of Saps as biomarkers were discussed. Furthermore, we examined the prospects of developing vaccines based on Saps and the use of protease inhibitors as adjunctive therapies for candidiasis. Given the complex biology of Saps and their central role in Candida pathogenicity, a multidisciplinary approach may pave the way for innovative diagnostic strategies and open new opportunities for innovative clinical interventions against candidiasis.
Collapse
Affiliation(s)
- Grazyna Bras
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
| | - Dorota Satala
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
| | - Magdalena Juszczak
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
- Doctoral School of Exact and Natural Sciences, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
| | - Kamila Kulig
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
| | - Ewelina Wronowska
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
| | - Aneta Bednarek
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
- Doctoral School of Exact and Natural Sciences, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
| | - Marcin Zawrotniak
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
| | - Maria Rapala-Kozik
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
| | - Justyna Karkowska-Kuleta
- Department of Comparative Biochemistry and Bioanalytics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland (M.Z.); (J.K.-K.)
| |
Collapse
|
2
|
Owens RA, Doyle S. Effects of antifungal agents on the fungal proteome: informing on mechanisms of sensitivity and resistance. Expert Rev Proteomics 2021; 18:185-199. [PMID: 33797307 DOI: 10.1080/14789450.2021.1912601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
INTRODUCTION Antifungal agents are essential in the fight against serious fungal disease, however emerging resistance is threatening an already limited collection of therapeutics. Proteomic analyses of effects of antifungal agents can expand our understanding of multifactorial mechanisms of action and have also proven valuable to elucidate proteomic changes associated with antifungal resistance. AREAS COVERED This review covers the application of proteomic techniques to examine sensitivity and resistance to antifungals including commonly used therapeutics, amphotericin B, echinocandins and the azoles, based predominantly on studies involving Aspergillus fumigatus, Candida albicans and Candida glabrata from the last 10 years. In addition, non-clinical antimicrobial agents are also discussed, which highlight the potential of proteomics to identify new antifungal targets. EXPERT COMMENTARY Fungal proteomics has evolved in the last decade with increased genome availability and developments in mass spectrometry. Collectively, these have led to the advancement of proteomic techniques, allowing increased coverage of the proteome. Gel-based proteomics laid the foundation for these types of studies, which has now shifted to the more powerful gel-free proteomics. This has resulted in the identification of key mediators and potential biomarkers of antifungal resistance, as well as elucidating the mechanisms of action of novel and established antifungal agents.
Collapse
Affiliation(s)
- Rebecca A Owens
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland.,The Kathleen Lonsdale Institute for Human Health Research, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| |
Collapse
|
3
|
Aspergillosis, Avian Species and the One Health Perspective: The Possible Importance of Birds in Azole Resistance. Microorganisms 2020; 8:microorganisms8122037. [PMID: 33352774 PMCID: PMC7767009 DOI: 10.3390/microorganisms8122037] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/11/2020] [Accepted: 12/17/2020] [Indexed: 12/30/2022] Open
Abstract
The One Health context considers health based on three pillars: humans, animals, and environment. This approach is a strong ally in the surveillance of infectious diseases and in the development of prevention strategies. Aspergillus spp. are fungi that fit substantially in this context, in view of their ubiquity, as well as their importance as plant pathogens, and potentially fatal pathogens for, particularly, humans and avian species. In addition, the emergence of azole resistance, mainly in Aspergillus fumigatus sensu stricto, and the proven role of fungicides widely used on crops, reinforces the need for a multidisciplinary approach to this problem. Avian species are involved in short and long distance travel between different types of landscapes, such as agricultural fields, natural environments and urban environments. Thus, birds can play an important role in the dispersion of Aspergillus, and of special concern, azole-resistant strains. In addition, some bird species are particularly susceptible to aspergillosis. Therefore, avian aspergillosis could be considered as an environmental health indicator. In this review, aspergillosis in humans and birds will be discussed, with focus on the presence of Aspergillus in the environment. We will relate these issues with the emergence of azole resistance on Aspergillus. These topics will be therefore considered and reviewed from the “One Health” perspective.
Collapse
|
4
|
Morais Vasconcelos Oliveira J, Conceição Oliver J, Latércia Tranches Dias A, Barbosa Padovan AC, Siqueira Caixeta E, Caixeta Franco Ariosa M. Detection of ERG11 Overexpression in Candida albicans isolates from environmental sources and clinical isolates treated with inhibitory and subinhibitory concentrations of fluconazole. Mycoses 2020; 64:220-227. [PMID: 33176021 DOI: 10.1111/myc.13208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 10/23/2020] [Accepted: 10/26/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Candida species can cause serious infection in patients with changes in defence mechanisms and/or when anatomical barriers are compromised. Mutations and overexpression in the ERG11 gene are described as molecular mechanisms of azole resistance. Information is limited on these mechanisms in the presence of subinhibitory concentrations of fluconazole. OBJECTIVES This study aimed to evaluate the expression of ERG11 gene from Candida albicans isolates, from clinical and hospital environments, in the absence and presence of inhibitory and subinhibitory concentrations of fluconazole. METHODS The American Type Culture Collection 10231 strain, five clinical isolates and three isolates from hospital environment colonisation were exposed to inhibitory and subinhibitory concentrations of fluconazole. Susceptibility tests were performed according to EUCAST 7.1 guidelines, and the relative expression analysis of ERG11 was performed by qPCR. RESULTS Differences in response to fluconazole concentrations were observed, with the exception only one clinical isolate when treated with 1/4 of the FLU-minimum inhibitory concentration (MIC). All the other isolates, regardless of the isolation source, had an increase in expression. The overexpression occurred in a very broad range, from 1.086 to 126.105 times. In general, treatment with the highest dose of fluconazole (MIC) was the one that most influenced the ERG11 expression, followed by treatments with 1/2 and 1/4 MIC. CONCLUSIONS The increased expression of ERG11 by C albicans in the presence of different concentrations of fluconazole is relevant, raising concerns in the care and cleaning of the hospital environment and the prophylactic use of fluconazole that could lead to the selection of potential azole-resistant isolates.
Collapse
Affiliation(s)
| | - Josidel Conceição Oliver
- Microbiology and Immunology Department, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil
| | | | - Ana Carolina Barbosa Padovan
- Microbiology and Immunology Department, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil
| | - Ester Siqueira Caixeta
- Department of Cell and Developmental Biology, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil
| | | |
Collapse
|
5
|
Orlandini RK, Bepu DAN, Saraiva MDCP, Bollela VR, Motta ACF, Lourenço AG. Are Candida albicans isolates from the oral cavity of HIV-infected patients more virulent than from non-HIV-infected patients? Systematic review and meta-analysis. Microb Pathog 2020; 149:104477. [PMID: 32920148 DOI: 10.1016/j.micpath.2020.104477] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/05/2020] [Accepted: 09/03/2020] [Indexed: 01/24/2023]
Abstract
Candida albicans is the main causative agent of oral lesions in HIV-infected patients and its oral colonization is a potential source of systemic dissemination. Although the high prevalence of lesions in HIV patients can be explained by the immunosuppressive condition, several studies have reported that natural selection can make C. albicans more virulent in this group of patients. Comparisons of the activity of exoenzymes (phospholipase, proteinase and hemolysin) in C. albicans isolated from HIV-infected and uninfected patients have yielded conflicting results. This study aimed, through a systematic review and meta-analysis, to answer the question: "Is the hydrolytic enzymatic activity of C. albicans, isolated from the oral cavity, different in individuals infected and not infected with HIV?" The question was addressed using the PECO framework: P (Population): children and adults, E (Exposure): HIV infection, C (Comparator): non-HIV-infected patients; O (Outcomes): exoenzymes activity i.e. phospholipase, proteinase and hemolysin. We conducted a systematic search on Pubmed, Embase, Scopus, Livivo, Lilacs, Web of Science, and Science Direct databases, and Google Scholar. The MAStARI tool was used to evaluate the risk of bias in the selected studies. From 2259 studies, 19 were included in this review and 11 comprised the meta-analysis. The activity of phospholipase (M-H = 0.15; Z = 2,76; p = 0.0006) and hemolysin exoenzymes (M-H = 0.07; z = 1,94; p = 0.05) was higher in C. albicans isolated from the oral cavity of HIV-infected patients, whereas the levels of protease activity were not different compared with non-HIV-infected individuals. This study showed a higher phospholipase and hemolysin activity in C. albicans isolates from the oral cavity of HIV-infected patients.
Collapse
Affiliation(s)
- Renata Klemp Orlandini
- Department of Basic and Oral Biology, Ribeirão Preto School of Dentistry, University of São Paulo, Brazil
| | - Davi Ariel Nobuo Bepu
- Department of Basic and Oral Biology, Ribeirão Preto School of Dentistry, University of São Paulo, Brazil
| | | | - Valdes Roberto Bollela
- Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo (FMRP-USP), Ribeirão Preto, São Paulo, Brazil
| | - Ana Carolina Fragoso Motta
- Department of Stomatology, Public Oral Health and Forensic Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Brazil
| | - Alan Grupioni Lourenço
- Department of Basic and Oral Biology, Ribeirão Preto School of Dentistry, University of São Paulo, Brazil.
| |
Collapse
|
6
|
Upregulation of secreted aspartyl proteinase genes of fluconazole-sensitive Candida albicans isolates. Mol Biol Rep 2019; 46:6147-6154. [PMID: 31602591 DOI: 10.1007/s11033-019-05049-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Accepted: 08/28/2019] [Indexed: 01/20/2023]
Abstract
Candida albicans infection development depends on several factors associated with this etiological agent, including secreted aspartyl protease (Sap) production. Sap expression commonly occurs under selective pressure caused by the presence of antifungals. Fluconazole is the main antifungal drug used for treatment or prophylaxis. This study investigated the influence of inhibitory and sub-inhibitory fluconazole concentrations on Sap activity and their gene transcription for three clinical C. albicans isolates. Two isolates presented significant increases in Sap activity and transcription of SAP 1-8 genes in the presence of 1 MIC80 of fluconazole compared to the absence of the antifungal agent. The results suggest that the increase in Sap activity occurs due to an upregulation of the SAP gene transcription influenced by fluconazole. This suggests the importance of all SAP genes in the progression of bloodstream infections compared to primary tissue infection. However, this phenomenon does not occur everywhere, and it is multifactorial. This may be related to the selective pressure effect on transcription modulators. Although preliminary, these results open a new perspective for the study of virulence factors.
Collapse
|
7
|
Gupta P, Gupta S, Sharma M, Kumar N, Pruthi V, Poluri KM. Effectiveness of Phytoactive Molecules on Transcriptional Expression, Biofilm Matrix, and Cell Wall Components of Candida glabrata and Its Clinical Isolates. ACS OMEGA 2018; 3:12201-12214. [PMID: 31459295 PMCID: PMC6645245 DOI: 10.1021/acsomega.8b01856] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/14/2018] [Indexed: 05/20/2023]
Abstract
Toxicity challenges by antifungal arsenals and emergence of multidrug resistance scenario has posed a serious threat to global community. To cope up with this alarming situation, phytoactive molecules are richest, safest, and most effective source of broad spectrum antimicrobial compounds. In the present investigation, six phytoactive molecules [cinnamaldehyde (CIN), epigallocatechin, vanillin, eugenol (EUG), furanone, and epigallocatechin gallate] were studied against Candida glabrata and its clinical isolates. Among these, CIN and EUG which are active components of cinnamon and clove essential oils, respectively, exhibited maximum inhibition against planktonic growth of C. glabrata at a concentration of 64 and 128 μg mL-1, respectively. These two molecules effectively inhibited and eradicated approximately 80% biofilm of C. glabrata and its clinical isolates from biomaterials. CIN and EUG increased reactive oxygen species generation, cell lysis, and ergosterol content in plasma membrane and reduced virulence attributes (phospholipase and proteinase) as well as catalase activity of C. glabrata cells. Reduction of mitochondrial membrane potential with increased release of cytochrome c from mitochondria to cytosol indicated initiation of early apoptosis in CIN- and EUG-treated C. glabrata cells. Transcriptional analysis showed that multidrug transporter (CDR1) and ergosterol biosynthesis genes were downregulated in the presence of CIN, while getting upregulated in EUG-treated cells. Interestingly, genes such as 1,3-β-glucan synthase (FKS1), GPI-anchored protein (KRE1), and sterol importer (AUS1) were downregulated upon treatment of CIN/EUG. These results provided molecular-level insights about the antifungal mechanism of CIN and EUG against C. glabrata including its resistant clinical isolate. The current data established that CIN and EUG can be potentially formulated in new antifungal strategies.
Collapse
Affiliation(s)
- Payal Gupta
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Sonam Gupta
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Meenakshi Sharma
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Navin Kumar
- Department
of Biotechnology, Graphic Era Deemed to
be University, Dehradun 248002, Uttarakhand, India
| | - Vikas Pruthi
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Krishna Mohan Poluri
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| |
Collapse
|
8
|
Effect of Saccharomyces boulardii Extract on SAP2 Gene Expression and Antifungal Susceptibility of Candida albicans. Jundishapur J Microbiol 2018. [DOI: 10.5812/jjm.59891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
9
|
Bhat V, Sharma SM, Shetty V, Shastry CS, Rao CV, Shenoy S, Saha S, Balaji S. Characterization of Herbal Antifungal Agent, Origanum vulgare against Oral Candida spp. Isolated from Patients with Candida-Associated Denture Stomatitis: An In vitro Study. Contemp Clin Dent 2018; 9:S3-S10. [PMID: 29962756 PMCID: PMC6006875 DOI: 10.4103/ccd.ccd_537_17] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Background: Candida Associated Denture Stomatitis is the prevalent fungal pathosis in denture wearers, especially in immunocompromized patients. Existing antifungal agents are ineffective since the Candida species become resistant and also, they become toxic. Origanum vulgare is a herbal plant with high anti-fungal activity against Candida of blood and urine origin. However, it has never been explored against Candida from oral cavity. Materials & Methodology: Dry leaves of the plant were purchased and authenticated. Oil extraction was done using Hydro-distillation method. Clinical isolates of Candida from denture wearers was speciated using CHROMagar. Well Diffusion test was used to confirm the antifungal activity. Hydro-distillation & Maceration methods of extraction were compared. MIC/MFC was determined using CSLI guidelines. Infra-Red Spectroscopy was used to identify the active functional group. Results: O.vulgare showed 30±3mm of zone of inhibition as against 19mm for fluconazole. The suitable extraction method was Hydro-distillation. MIC & MFC were found to be 0.024% and 0.097% respectively which was much lesser than for fluconazole (0.25%). The active functional group had chemically similar structure as Carvacrol, usually found in antifungal herbs. Conclusion: within the limitations of the study, it was concluded that (a)O.vulgare is anticandidal for clinical isolates of oral Candida, (b) Hydro-distillation is an effective method as compared to Maceration (c) MIC & MFC are much lower than that of fluconazole (d) the major functional group was structurally similar to Carvacrol.
Collapse
Affiliation(s)
- Vinaya Bhat
- Department of Prosthodontics, A B Shetty Memorial Institute of Dental Sciences, NITTE (Deemed to be University), Mangalore, Karnataka, India
| | - S M Sharma
- Department of Oral and Maxillofacial Surgery, ABSMIDS, NITTE (Deemed to be University), Mangalore, Karnataka, India
| | - Veena Shetty
- Department of Microbiology, KSHEMA, NITTE (Deemed to be University), Mangalore, Karnataka, India
| | - C S Shastry
- Principal, NGSM Institute of Pharmaceutical Sciences, NITTE (Deemed to be University), Mangalore, Karnataka, India
| | - C Vaman Rao
- Department of Biotechnology, NMAM Institute of Technology, NITTE (Deemed to be University), Mangalore, Karnataka, India
| | - Shilpa Shenoy
- Department of Microbiology, NITTE (Deemed to be University), Mangalore, Karnataka, India
| | - Santanu Saha
- Department of Pharmacognosy, NGSM Institute of Pharmaceutical Sciences, NITTE (Deemed to be University), Mangalore, Karnataka, India
| | - Sriram Balaji
- Department of Prosthodontics, Sri Ramakrishna Dental College and Hospitals, Coimbatore, Tamil Nadu, India
| |
Collapse
|
10
|
Raja V, Ahmad SI, Irshad M, Wani WA, Siddiqi WA, Shreaz S. Anticandidal activity of ethanolic root extract of Juglans regia (L.): Effect on growth, cell morphology, and key virulence factors. J Mycol Med 2017; 27:476-486. [PMID: 28784433 DOI: 10.1016/j.mycmed.2017.07.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 06/29/2017] [Accepted: 07/01/2017] [Indexed: 01/20/2023]
Abstract
The emergence of drug-resistant strains has encouraged several studies on natural products with antifungal activity and low toxicity. In this study, the antifungal effect of methanolic root extract of Juglans regia (JRE) was investigated against 9 strains of Candida (one reference and 8 clinical strains) through MIC90 and spot assays. To gain insight into the mechanism of antifungal action, we carried out confocal scanning laser microscopy (CLSM), transmission electron microscopy (TEM), and then examined the effect of JRE on hydrolytic enzyme secretion. Additionally, JRE was subjected to various phytochemical tests, chemically characterized by gas chromatography-mass spectrometry analysis (GC-MS) and its toxicity was tested against H9c2 rat cardiac myoblasts. The phytochemical tests showed the presence of phenols, alkaloids, steroids, saponins, and tannins in JRE. In the GC-MS analysis, a total of 40 compounds were identified. JRE was found to be effective in liquid media with MICs ranging from 300 to 700μg/mL. Spot assay results revealed that Candida cells show increased sensitivity to JRE. CSLM experiments showed that cells exposed to JRE (MIC) exhibited cell membrane disruption. TEM micrograph of treated cells showed extensive breakage in the cell wall and cell membrane. Average inhibition of proteinase and phospholipase secretion (of five C. albicans strains) at MIC/2 values of JRE was 45.17%, and 34.29%, respectively. Cellular toxicity of JRE against H9c2 rat cardiac myoblasts was less than 10% at the highest MIC value. These findings encourage further development of JRE.
Collapse
Affiliation(s)
- V Raja
- Department of Applied Sciences & Humanities, Faculty of Engineering & Technology, Jamia Millia Islamia, 110025 New Delhi, India
| | - S I Ahmad
- Department of Applied Sciences & Humanities, Faculty of Engineering & Technology, Jamia Millia Islamia, 110025 New Delhi, India
| | - M Irshad
- Oral Microbiology Laboratory, Department of Bioclinical Sciences, Faculty of Dentistry, Health Sciences Center, Kuwait University, PO Box 24923, 13110 Safat, Kuwait
| | - W A Wani
- Department of Chemistry, Government Degree College Tral, PO Box 192123, Kashmir, Jammu and Kashmir, India
| | - W A Siddiqi
- Department of Applied Sciences & Humanities, Faculty of Engineering & Technology, Jamia Millia Islamia, 110025 New Delhi, India
| | - S Shreaz
- Oral Microbiology Laboratory, Department of Bioclinical Sciences, Faculty of Dentistry, Health Sciences Center, Kuwait University, PO Box 24923, 13110 Safat, Kuwait; Environment and Life Sciences Research Center, Kuwait Institute for Scientific, Research, PO Box 24885, 13109 Safat, Kuwait.
| |
Collapse
|
11
|
|
12
|
Sulfone derivatives reduce growth, adhesion and aspartic protease SAP2 gene expression. World J Microbiol Biotechnol 2014; 30:2511-21. [DOI: 10.1007/s11274-014-1676-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 05/21/2014] [Indexed: 10/25/2022]
|
13
|
Sadowska B, Budzyńska A, Więckowska-Szakiel M, Paszkiewicz M, Stochmal A, Moniuszko-Szajwaj B, Kowalczyk M, Różalska B. New pharmacological properties of Medicago sativa and Saponaria officinalis saponin-rich fractions addressed to Candida albicans. J Med Microbiol 2014; 63:1076-1086. [PMID: 24850879 DOI: 10.1099/jmm.0.075291-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The antifungal activity of the saponin-rich fractions (SFs) from Medicago sativa (aerial parts and roots) and Saponaria officinalis (used as a well-known source of plant saponins) against Candida albicans reference and clinical strains, their yeast-to-hyphal conversion, adhesion, and biofilm formation was investigated. Direct fungicidal/fungistatic properties of the tested phytochemicals used alone, as well as their synergy with azoles (probably resulting from yeast cell wall instability) were demonstrated. Here, to the best of our knowledge, we report for the first time the ability of saponin-rich extracts of M. sativa and S. officinalis to inhibit C. albicans germ tube formation, limit hyphal growth, reduce yeast adherence and biofilm formation, and eradicate mature (24 h) Candida biofilm. Moreover, M. sativa SFs (mainly obtained from aerial parts), in the range of concentrations which were active modulators of Candida virulence factors, exhibited low cytotoxicity against the mouse fibroblast line L929. These properties seem to be very promising in the context of using plant-derived SFs as potential novel antifungal therapeutics supporting classic drugs or as ingredients of disinfectants.
Collapse
Affiliation(s)
- Beata Sadowska
- Department of Infectious Biology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland
| | - Aleksandra Budzyńska
- Department of Infectious Biology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland
| | - Marzena Więckowska-Szakiel
- Department of Infectious Biology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland
| | - Małgorzata Paszkiewicz
- Department of Infectious Biology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland
| | - Anna Stochmal
- Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
| | - Barbara Moniuszko-Szajwaj
- Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
| | - Mariusz Kowalczyk
- Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
| | - Barbara Różalska
- Department of Infectious Biology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland
| |
Collapse
|
14
|
Souza JLS, da Silva AF, Carvalho PHA, Pacheco BS, Pereira CMP, Lund RG. Aliphatic fatty acids and esters: inhibition of growth and exoenzyme production of Candida, and their cytotoxicity in vitro: anti-Candida effect and cytotoxicity of fatty acids and esters. Arch Oral Biol 2014; 59:880-6. [PMID: 24907517 DOI: 10.1016/j.archoralbio.2014.05.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 04/09/2014] [Accepted: 05/12/2014] [Indexed: 10/25/2022]
Abstract
The secretion of extracellular phospholipases and proteinases of Candida has been described as a relevant virulence factor in human infections. Aliphatic fatty acids have antimicrobial properties, but the mechanism by which they affect the virulence factors of microorganisms, such as Candida, is still unclear, and there are a few reports about their toxicity. The current study investigated the in vitro antifungal activity, exoenzyme production and cytotoxicity of some aliphatic fatty acids and their ester derivatives against the Candida species. The minimum inhibitory concentration and minimum fungicidal concentrations of aliphatic medium-chain fatty acids, methyl and ethyl esters were performed using the CLSI M27-A3 method and the cytotoxicity assay was performed according to ISO 10993-5. The influence of these compounds in the inhibition of the production of hydrolytic enzymes, phospholipases and proteinases by Candida was also investigated. Data analysis was performed using the one-way ANOVA method (p≤0.05). In relation to the MIC against Candida species, the fatty acid with the best result was Lauric acid, although its ester derivatives showed no activity. The inhibition of phospholipase production was more significant than the inhibition of proteinase production by Candida. Tested fatty acids revealed more than 80% cell viability in their MIC concentrations. Additionally, a cell viability of 100% was reported at concentrations of anti-enzymatic effect. Therefore, the potential use of these fatty acids could be the basis for more antimicrobial tests.
Collapse
Affiliation(s)
- Juliana L S Souza
- Laboratory of Microbiology, Postgraduate Program in Biochemistry and Bioprospection, Federal University of Pelotas (UFPel) - Gonçalves Chaves, 457/702, 96015-560 Pelotas, RS, Brazil
| | - Adriana F da Silva
- School of Dentistry, Federal University of Pelotas (UFPel) - Gonçalves Chaves, 457/503, 96015-560 Pelotas, RS, Brazil
| | - Pedro H A Carvalho
- Laboratory of Microbiology, Postgraduate Program in Biochemistry and Bioprospection, Federal University of Pelotas (UFPel) - Gonçalves Chaves, 457/702, 96015-560 Pelotas, RS, Brazil
| | - Bruna S Pacheco
- Center for Chemical, Pharmaceutical and Food Sciences, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Cláudio M P Pereira
- Center for Chemical, Pharmaceutical and Food Sciences, Federal University of Pelotas, Pelotas, RS, Brazil
| | - Rafael G Lund
- Laboratory of Microbiology, Postgraduate Program in Biochemistry and Bioprospection, Federal University of Pelotas (UFPel) - Gonçalves Chaves, 457/702, 96015-560 Pelotas, RS, Brazil.
| |
Collapse
|
15
|
Antifungal susceptibility, exoenzyme production and cytotoxicity of novel oximes against Candida. Mycopathologia 2013; 176:201-10. [PMID: 23824511 DOI: 10.1007/s11046-013-9675-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 06/21/2013] [Indexed: 10/26/2022]
Abstract
Novel oximes were synthesized, their in vitro antifungal activity against Candida was evaluated and their cytotoxicity was determined. The procedure used for the synthesis of the oximes is aligned with the current green chemistry trend; water is employed as the solvent in this reaction. The minimum inhibitory and minimum fungicidal concentrations of the oximes were evaluated using the CLSI M27-A3 method. The influence of these compounds on the inhibition of the production of hydrolytic enzymes, phospholipase and proteinase by Candida was also investigated. The compounds showed a good ability to inhibit phospholipase, with a 50 % reduction in most cases. However, the tested compounds did not affect proteinase. The current results showed a substantial reduction in the phospholipase production, which suggests that compounds of this class may interfere with host infection and disease progression. The oximes examined showed lower fungicidal activities than fluconazole but interfered significantly with the expression of phospholipase. Some of the oximes included in this study could be a suitable matrix for the development of novel antifungal compounds.
Collapse
|
16
|
Silva NC, Nery JM, Dias ALT. Aspartic proteinases of Candida spp.: role in pathogenicity and antifungal resistance. Mycoses 2013; 57:1-11. [PMID: 23735296 DOI: 10.1111/myc.12095] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Revised: 05/03/2013] [Accepted: 05/08/2013] [Indexed: 12/20/2022]
Abstract
Fungal infections represent a serious health risk as they are particularly prevalent in immunocompromised individuals. Candida spp. pathogenicity depends on several factors and secreted aspartic proteinases (Sap) are considered one of the most critical factors as they are associated with adhesion, invasion and tissue damage. The production of proteinases is encoded by a family of 10 genes known as SAP, which are distributed differently among the species. The expression of these genes may be influenced by environmental conditions, which generally result in a higher fungal invasive potential. Non-pathogenic Candida spp. usually have fewer SAP genes, which are not necessarily expressed in the genome. Exposure to subinhibitory concentrations of antifungal agents promotes the development of resistant strains with an increased expression of SAP genes. In general, Candida spp. isolates that are resistant to antifungals show a higher secretion of Sap than the susceptible isolates. The relationship between Sap secretion and the susceptibility profile of the isolates is of great interest, although the role of SAPs in the development of resistance to antifungal agents remains still unclear. This review is the first one to address these issues.
Collapse
Affiliation(s)
- Naiara C Silva
- Microbiology and Immunology Department, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil
| | | | | |
Collapse
|
17
|
Bicyclic peptidomimetics targeting secreted aspartic protease 2 (SAP2) from Candida albicans reveal a constrained inhibitory chemotype. Bioorg Med Chem 2012; 20:7206-13. [DOI: 10.1016/j.bmc.2012.09.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 09/06/2012] [Accepted: 09/11/2012] [Indexed: 11/22/2022]
|
18
|
Gonçalves LM, Del Bel Cury AA, Sartoratto A, Garcia Rehder VL, Silva WJ. Effects of undecylenic acid released from denture liner on Candida biofilms. J Dent Res 2012; 91:985-9. [PMID: 22904206 DOI: 10.1177/0022034512458689] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Denture liners (DL) are easily colonized by Candida spp. In an attempt to prevent biofilm colonization, manufacturers have incorporated undecylenic acid (UDA) into DL. In this in vitro study, the effects of UDA released from DL on Candida biofilms were investigated. The concentrations of UDA released from commercial DL were determined by gas chromatography-mass spectrometry (GC-MS). Minimum inhibitory concentration (MIC) and minimum fungistatic concentration (MFC) tests were performed for C. albicans or C. glabrata, with UDA for comparison with the concentrations released from DL. Specimens of DL with (experimental group) and without UDA (control group) were fabricated, and Candida biofilms were developed on DL surfaces. Biofilms were evaluated by cell counts, metabolic activity, structure, and secretion of proteinase or phospholipase. The concentrations of UDA released were within the MIC and MFC ranges. In the presence of UDA, C. albicans biofilms were thinner and had lower numbers of viable and active cells, although no significant enzymatic changes were observed relative to the control group (p > 0.05). In contrast, C. glabrata biofilms exhibited higher cell counts and greater metabolic activity and also increased proteinase activity in the presence of UDA relative to the control group (p < 0.05). Overall, UDA did not prevent Candida biofilm formation.
Collapse
Affiliation(s)
- L M Gonçalves
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Avenida Limeira, 901, 13414-903 Piracicaba, São Paulo, Brazil
| | | | | | | | | |
Collapse
|
19
|
Cinnamic aldehydes affect hydrolytic enzyme secretion and morphogenesis in oral Candida isolates. Microb Pathog 2012; 52:251-8. [DOI: 10.1016/j.micpath.2011.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 11/21/2011] [Accepted: 11/30/2011] [Indexed: 11/22/2022]
|
20
|
Dornelas-Ribeiro M, Pinheiro EO, Guerra C, Braga-Silva LA, Carvalho SMFD, Santos ALSD, Rozental S, Fracalanzza SEL. Cellular characterisation of Candida tropicalis presenting fluconazole-related trailing growth. Mem Inst Oswaldo Cruz 2012; 107:31-8. [DOI: 10.1590/s0074-02762012000100005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Accepted: 08/16/2011] [Indexed: 11/22/2022] Open
Affiliation(s)
- Marcos Dornelas-Ribeiro
- Instituto de Biologia do Exército, Brasil; Instituto Estadual de Hematologia, Brasil; Hospital Adventista Silvestre, Brasil; Instituto de Microbiologia Paulo de Góes
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Ying S, Chunyang L. Correlation between phospholipase of Candida albicans and resistance to fluconazole. Mycoses 2011; 55:50-5. [PMID: 21623950 DOI: 10.1111/j.1439-0507.2011.02024.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The objective of this study was to compare phospholipase production between fluconazole-resistant and fluconazole-susceptible strains of Candida albicans in order to explore the relationship between resistance to antifungal drugs and virulence of C. albicans. Fifteen each of fluconazole-resistant (MIC ≥ 64 μg ml(-1)) and fluconazole-susceptible (MIC ≤ 8 μg ml(-1)) strains of C. albicans were incubated on egg yolk agar to detect phospholipase activity. Virulence of C. albicans was assessed by the average survival time of infected mice. Expression of phospholipase B1 mRNA and protein were detected by RT-PCR and Western blot method. Significant differences between the two groups of Candida strains were observed in phospholipase activity and average survival time of infected mice. The expression of phospholipase B1 mRNA and protein (both of secreted and intracellular forms) were higher in resistant strains than in susceptible strains. The results indicate that the phospholipase activity of C. albicans may be related to its resistance to antifungal drugs.
Collapse
Affiliation(s)
- Su Ying
- Department of Dermatology and Ethology, Qilu Hospital affiliated to Shandong University, Jinan, China
| | | |
Collapse
|
22
|
Schulz B, Weber K, Schmidt A, Borg-von Zepelin M, Ruhnke M. Difference in virulence between fluconazole-susceptible and fluconazole-resistant Candida albicans in a mouse model. Mycoses 2011; 54:e522-30. [DOI: 10.1111/j.1439-0507.2010.01970.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
23
|
Neelofar K, Shreaz S, Rimple B, Muralidhar S, Nikhat M, Khan LA. Curcumin as a promising anticandidal of clinical interest. Can J Microbiol 2011; 57:204-10. [PMID: 21358761 DOI: 10.1139/w10-117] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Curcumin, an important Asian spice, is part of many Indian food preparations. This work evaluates the antifungal activity of curcumin against 14 strains of Candida (10 clinical and 4 standard). Curcumin displayed antifungal properties against all tested Candida strains, with minimum inhibitory concentrations (MICs) varying from 250 to 2000 µg·mL⁻¹. The in vitro effect of curcumin on growth, sterol content, proteinase secretion, and H+ extrusion by plasma membrane ATPase was investigated for 2 standard strains Candida albicans ATCC 10261 and Candida glabrata ATCC 90030 and compared with the effect of fluconazole. At MIC, curcumin inhibited H+ extrusion in 2 species of Candida by 42% and 32% in the absence of glucose and by 28% and 18% in the presence of glucose. Respective inhibition of H+ extrusion caused by the MIC of fluconazole was 85% and 89% in the absence of glucose and 61% and 66% in its presence. Ergosterol content decreased by 70% and 53% for the 2 strains following exposure to curcumin at MIC; comparative values for fluconazole at MIC were 93% and 98%. Curcumin and fluconazole decreased proteinase secretion by 49% and 53%, respectively, in C. albicans and by 39% and 46%, respectively, in C. glabrata. In conclusion, curcumin is found to be active against all tested clinical and standard strains but is less effective than fluconazole. Antifungal activity of curcumin might be originating from alteration of membrane-associated properties of ATPase activity, ergosterol biosynthesis, and proteinase secretion.
Collapse
Affiliation(s)
- K Neelofar
- Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India
| | | | | | | | | | | |
Collapse
|
24
|
Mores AU, Souza RD, Cavalca L, de Paula e Carvalho A, Gursky LC, Rosa RT, Samaranayake LP, Rosa EAR. Enhancement of Secretory Aspartyl Protease production in biofilms of Candida albicans exposed to sub-inhibitory concentrations of fluconazole. Mycoses 2011; 54:195-201. [DOI: 10.1111/j.1439-0507.2009.01793.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
25
|
Calugi C, Trabocchi A, Guarna A. Novel small molecules for the treatment of infections caused byCandida albicans: a patent review (2002 – 2010). Expert Opin Ther Pat 2011; 21:381-97. [DOI: 10.1517/13543776.2011.551116] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
26
|
Amphotericin B resistance leads to enhanced proteinase and phospholipase activity and reduced germ tube formation in Candida albicans. Fungal Biol 2010; 114:189-97. [DOI: 10.1016/j.funbio.2009.12.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 12/08/2009] [Accepted: 12/14/2009] [Indexed: 11/24/2022]
|
27
|
Costa CR, Jesuíno RSA, de Aquino Lemos J, de Fátima Lisboa Fernandes O, Hasimoto e Souza LK, Passos XS, do Rosário Rodrigues Silva M. Effects of Antifungal Agents in Sap Activity of Candida albicans Isolates. Mycopathologia 2009; 169:91-8. [DOI: 10.1007/s11046-009-9232-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2009] [Accepted: 07/31/2009] [Indexed: 01/12/2023]
|
28
|
Targeting virulence: A new paradigm for antifungals. Drug Discov Today 2009; 14:214-22. [DOI: 10.1016/j.drudis.2008.11.013] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Revised: 11/04/2008] [Accepted: 11/17/2008] [Indexed: 11/17/2022]
|
29
|
Vogel M, Hartmann T, Köberle M, Treiber M, Autenrieth IB, Schumacher UK. Rifampicin induces MDR1 expression in Candida albicans. J Antimicrob Chemother 2008; 61:541-7. [PMID: 18238892 DOI: 10.1093/jac/dkm513] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Overexpression of efflux pumps such as MDR1 has been identified as an important mechanism contributing to fluconazole resistance in Candida albicans. This phenomenon is frequently observed in fluconazole-resistant strains isolated from AIDS patients treated with various pharmaceuticals. Therefore, we hypothesized that some of these compounds might influence the expression of genes responsible for fluconazole resistance. METHODS We examined a variety of clinically relevant compounds for their in vitro effects on MDR1 expression with a C. albicans reporter strain containing a transcriptional fusion of the MDR1 promoter (MDR1P) with the gfp gene. Activation of the MDR1 promoter and subsequent green fluorescent protein production was determined by fluorescence microscopy and flow cytometry. Additionally, MDR1 transcription was confirmed and quantified by RT-PCR analysis, followed by Mdr1p detection by western blot. Finally, the effect of a selected agent on resistance to fluconazole was tested by chequerboard titration of both substances. RESULTS Of 15 compounds tested, only rifampicin induced a rapid and dose-dependent increase in MDR1 expression (up to 122-fold induction), whereas structurally related molecules such as rifabutin and rifamycin were not active. Induction of MDR1 expression upon rifampicin exposure was also observed in 10 blood culture isolates. In contrast, rifampicin exposure did not markedly affect the expression of the transporters CDR1 and CDR2. Increased MDR1 expression was accompanied by elevated MICs for fluconazole after exposure of C. albicans to rifampicin, whereas Mdr1p expression was only moderately induced. CONCLUSIONS Out of the compounds examined, only rifampicin specifically induced MDR1 expression in all C. albicans strains tested. Rifampicin may play a general role in signal transduction or another means of modulation of gene expression in C. albicans.
Collapse
Affiliation(s)
- Miriam Vogel
- Institut für Medizinische Mikrobiologie und Hygiene, Eberhard-Karls-Universität, 72076 Tübingen, Germany
| | | | | | | | | | | |
Collapse
|
30
|
. MKAS, . KHAE, . AZE, . MAH, . RFK. Influence of Various Ultraviolet Light Intensities on Pathogenic Determinants of Candida albicans. ACTA ACUST UNITED AC 2007. [DOI: 10.3923/biotech.2007.210.217] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
31
|
Bruzual I, Riggle P, Hadley S, Kumamoto CA. Biofilm formation by fluconazole-resistant Candida albicans strains is inhibited by fluconazole. J Antimicrob Chemother 2007; 59:441-50. [PMID: 17261564 DOI: 10.1093/jac/dkl521] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES The fungal pathogen Candida albicans forms biofilms on implanted medical devices, resulting in infections with high mortality. Fully developed biofilms, which are adherent communities of microorganisms, characteristically exhibit high resistance to antimicrobial drugs, making treatment of device-associated infection problematic. The aim of this study was to determine the effect of the addition of the azole antifungal fluconazole on the initiation of biofilm formation by both drug-susceptible and drug-resistant C. albicans strains. RESULTS Our data reported here show that biofilm formation by both fluconazole-susceptible and fluconazole-resistant C. albicans strains was inhibited when fluconazole was present. For the fluconazole-susceptible strains, inhibition of growth due to the presence of the antifungal drug probably prevented the acquisition of high-level fluconazole resistance. However, for fluconazole-resistant strains, the inhibition of biofilm development was unexpected. CONCLUSIONS Unexpectedly, fluconazole inhibited biofilm formation by a variety of laboratory isolated and clinically isolated fluconazole-resistant strains.
Collapse
Affiliation(s)
- Igor Bruzual
- Department of Molecular Biology and Microbiology, Tufts University, 136 Harrison Ave., Boston, MA 02111, USA
| | | | | | | |
Collapse
|
32
|
Lyon JP, de Resende MA. Correlation between adhesion, enzyme production, and susceptibility to fluconazole in Candida albicans obtained from denture wearers. ACTA ACUST UNITED AC 2006; 102:632-8. [PMID: 17052640 DOI: 10.1016/j.tripleo.2005.12.015] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Revised: 07/29/2005] [Accepted: 12/12/2005] [Indexed: 11/23/2022]
Abstract
OBJECTIVE The aim of this study was to assess the contribution and the correlation between the virulence factors of Candida albicans in denture stomatitis. STUDY DESIGN Thirty C. albicans strains obtained from the oral cavity of patients with denture stomatitis and 30 C. albicans obtained from the oral cavity of denture wearers with normal palatal mucosa were compared for adhesion ability to buccal epithelial cells (BEC), reduction in adhesion after exposure to fluconazole, and enzyme production. The correlation between these virulence factors was assessed by Pearson's correlation coefficient. RESULTS C. albicans obtained from denture stomatitis patients were more adherent to BEC and higher enzyme producers than those obtained from healthy patients. Our results demonstrated that exposure to fluconazole reduces C. albicans adherence to BEC. This study could also provide evidence of correlation between virulence factors. CONCLUSION Our results suggest that adhesion and enzyme production could be factors that, along with predisposing conditions related to the host, determine if an individual will develop disease or remain as a healthy carrier and confirm that fluconazole has an impact on the adherence ability and enzyme production in C. albicans.
Collapse
Affiliation(s)
- Juliana P Lyon
- Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais
| | | |
Collapse
|
33
|
Imbert C, Imbert-Bouyer S, Kauffmann-Lacroix C, Daniault G, Rodier MH. Effect of Azoles on the Secretion of a Candida albicans Metallopeptidase. Mycopathologia 2006; 161:147-52. [PMID: 16482386 DOI: 10.1007/s11046-005-3085-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Accepted: 11/07/2005] [Indexed: 10/25/2022]
Abstract
Azole antifungals act by inhibiting the activity of a lanosterol demethylase involved in the generation of the ergosterol of the cellular membrane of fungi. These drugs could also have action on other yeast components, like secreted aspartyl proteases. We demonstrate in this study that the in vitro secretion of a metallopeptidase could be modified during the growth of Candida albicans with subinhibitory concentrations of some azoles. Eight isolates of this yeast have been cultivated in presence of MIC, MIC/2 and MIC/4 of voriconazole, fluconazole and itraconazole. The presence of voriconazole and fluconazole decreased the secretion of the metallopeptidase in the culture medium, whereas itraconazole increased this secretion for three isolates. This study points to the fact that some antifungals, given in prophylaxis, could act in an unfavourable way on some potential factors of pathogenicity.
Collapse
Affiliation(s)
- Christine Imbert
- Unité de recherche en biologie parasitaire et fongique, Laboratoire de parasitologie et mycologie médicales, CHU La Milètrie, Poitiers, France.
| | | | | | | | | |
Collapse
|
34
|
Sanguinetti M, Posteraro B, La Sorda M, Torelli R, Fiori B, Santangelo R, Delogu G, Fadda G. Role of AFR1, an ABC transporter-encoding gene, in the in vivo response to fluconazole and virulence of Cryptococcus neoformans. Infect Immun 2006; 74:1352-9. [PMID: 16428784 PMCID: PMC1360305 DOI: 10.1128/iai.74.2.1352-1359.2006] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have recently demonstrated that upregulation of the ATP binding cassette (ABC) transporter-encoding gene AFR1 in Cryptococcus neoformans is involved in the in vitro resistance to fluconazole of this yeast. In the present study, we investigated the role of AFR1 in the in vivo response to fluconazole in a mouse model of systemic cryptococcosis. Mice were infected with a wild-type fluconazole-susceptible strain of C. neoformans, strain BPY22; an afr1 mutant, BPY444, which displayed hypersusceptibility to fluconazole in vitro; or an AFR1-overexpressing strain, BPY445, which exhibited in vitro resistance to the drug. In each of the three groups, infected animals were randomly assigned to fluconazole treatment or untreated-control subgroups. As expected, fluconazole prolonged survival and reduced fungal tissue burdens (compared with no treatment) in BPY22- and BPY444-infected mice, whereas it had no significant effects in mice infected with BPY445. When the pathogenicities of these strains in mice were investigated, strain BPY445 was significantly more virulent than BPY22 following inhalational or intravenous inoculation, but mice infected with BPY444 survived significantly longer than BPY22-infected animals only when infection was acquired via the respiratory tract. In in vitro macrophage infection studies, strain BPY445 also displayed enhanced intracellular survival compared with strains BPY22 and BPY444, suggesting that its increased virulence may be due to its reduced vulnerability to the antimicrobial factors produced by phagocytic cells. These findings indicate that the upregulation of the AFR1 gene is an important factor in either determining the in vivo resistance to fluconazole or influencing the virulence of C. neoformans.
Collapse
Affiliation(s)
- Maurizio Sanguinetti
- Istituto di Microbiologia, Università Cattolica del Sacro Cuore, Largo F. Vito 1, Rome 00168, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Navarathna DHMLP, Hornby JM, Hoerrmann N, Parkhurst AM, Duhamel GE, Nickerson KW. Enhanced pathogenicity of Candida albicans pre-treated with subinhibitory concentrations of fluconazole in a mouse model of disseminated candidiasis. J Antimicrob Chemother 2005; 56:1156-9. [PMID: 16239285 DOI: 10.1093/jac/dki383] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES To investigate the relative pathogenicity of Candida albicans treated with subinhibitory concentrations of fluconazole in a mouse model of disseminated candidiasis. Previous studies indicate that these cells secrete 10 times more farnesol than do untreated cells. In our usage, subinhibitory means a concentration which causes a prominent decrease in turbidity but still allows some cell growth. METHODS C. albicans A72 cells were grown overnight in 0-5.0 microM fluconazole, washed, and inoculated in mice by tail vein injection. Groups of 15 or 16 mice were injected with 1.3 x 10(6) cells and mortality was recorded for 7 days post-inoculation. The levels of farnesol in control and treated C. albicans were determined by GC/MS. RESULTS The MIC50 for strain A72 was 0.125 mg/L (0.4 microM). Mice administered C. albicans pre-treated with 0.5 to 1.0 microM fluconazole died 2.5 to 4 days earlier and had 2 to 4 times higher mortality rates than mice given untreated C. albicans. Fluconazole (0.5 to 1.0 microM) pre-treated cells were 4.2 to 8.5 times more lethal (P < 0.001) than untreated cells. The extracellular, membrane bound, and intracellular farnesol concentrations of cells pre-treated with 1.0 muM fluconazole were 12-, 2- and 6-times those of untreated cells. CONCLUSIONS The effects of fluconazole on C. albicans are very concentration-dependent. The enhanced pathogenicity of fluconazole pre-treated C. albicans in mice should be relevant to the therapeutic and prophylactic use of fluconazole. Further research is needed to explore whether farnesol production by C. albicans is a virulence factor.
Collapse
|
36
|
Kalkanci A, Bozdayi G, Biri A, Kustimur S. Distribution of secreted aspartyl proteinases using a polymerase chain reaction assay withSAP specific primers inCandida albicans isolates. Folia Microbiol (Praha) 2005; 50:409-13. [PMID: 16475500 DOI: 10.1007/bf02931422] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Secreted aspartyl proteinase (Sap) distribution among different C. albicans isolates was determined using SAP-specific primers in polymerase chain reaction (PCR) assay. SAP1, SAP2, and SAP3 were detected in 13 of 40 (32.5%), SAP4 in 38/40 (95%), SAP5 were detected in 30/40 (75%), SAP6 in 23/40 (57.5%) of C. albicans strains isolated from blood cultures. SAP1-SAP3 were detected in 37 of 40 (92.5%), SAP4 were detected in 3/40 (7.5%), SAP5 in 3/40 (7.5%), SAP6 in 5/40 (12.5%) of C. albicans strains isolated from vaginal swab cultures. Sap1, Sap2 and Sap3 isoenzymes were found to be related to the vaginopathic potential of C. albicans; Sap4, Sap5 and Sap6 isoenzymes were found to be correlated with systemic infections.
Collapse
Affiliation(s)
- A Kalkanci
- Department of Microbiology, Faculty of Medicine, Gazi University, 06510 Ankara, Turkey.
| | | | | | | |
Collapse
|
37
|
Copping VMS, Barelle CJ, Hube B, Gow NAR, Brown AJP, Odds FC. Exposure of Candida albicans to antifungal agents affects expression of SAP2 and SAP9 secreted proteinase genes. J Antimicrob Chemother 2005; 55:645-54. [PMID: 15820985 DOI: 10.1093/jac/dki088] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES To ascertain the effects of subinhibitory concentrations of several antifungal agents on a virulence factor: secreted proteinase (Sap) activity and expression of SAP genes in Candida albicans. METHODS Enzyme assays and growth measurements, GFP-SAP2 promoter constructs and fluorescence measurement, transcript profiling and RT-PCR. RESULTS For seven of eight C. albicans isolates tested, exposure to fluconazole gave an increase in Sap specific activity; for one isolate, resistant to azoles and flucytosine, fluconazole exposure led to a fall in Sap activity. A similar relationship between growth reduction and increased Sap activity was seen with C. albicans cells treated with subinhibitory concentrations of itraconazole, miconazole, flucytosine and caspofungin. Transcript profiling indicated antifungal exposure was associated with increased expression of mRNA from SAP2 and SAP9 genes; this was confirmed for fluconazole and caspofungin exposure by RT-PCR. CONCLUSIONS Antifungal agents with three different mechanisms of action similarly generate a rise in expression of SAP2 and activity of the secreted Sap2 gene product, a known virulence factor, in most isolates of C. albicans. One isolate of the fungus showed an opposite response.
Collapse
Affiliation(s)
- Vanessa M S Copping
- Aberdeen Fungal Group, School of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | | | | | | | | | | |
Collapse
|
38
|
De Bernardis F, Tacconelli E, Mondello F, Cataldo A, Arancia S, Cauda R, Cassone A. Anti-retroviral therapy with protease inhibitors decreases virulence enzyme expression in vivo by Candida albicans without selection of avirulent fungus strains or decreasing their anti-mycotic susceptibility. ACTA ACUST UNITED AC 2004; 41:27-34. [PMID: 15094164 DOI: 10.1016/j.femsim.2003.12.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2003] [Revised: 12/22/2003] [Accepted: 12/24/2003] [Indexed: 11/18/2022]
Abstract
Highly active anti-retroviral therapies (HAART) with human immunodeficiency virus (HIV) protease inhibitors (PIs) or nonnucleoside reverse-transcriptase inhibitors (NNRTI) were compared for their effect on prevalence, aspartyl proteinase (Sap) production and the biotypes and anti-mycotic sequential susceptibility of Candida spp. isolates from the oral cavity in a longitudinal prospective study. HAART-PI, but not HAART-NNRTI strongly inhibited Sap expression in the oral cavity without exerting any consistent effect on the role of Candida spp. isolation or selection of low virulence or anti-mycotic resistant fungus biotype. More importantly, the sequential isolates of Candida albicans from HAART-PI, but not those from suspended HAART-NNRTI, showed an increased Sap production in vitro. While further demonstrating that HIV-PI inhibit Sap expressions, our results do not support the view that the mentioned inhibition could eliminate Candida or its selection of the oral cavity.
Collapse
Affiliation(s)
- Flavia De Bernardis
- Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, Rome 00161, Italy.
| | | | | | | | | | | | | |
Collapse
|
39
|
Morrison CJ, Hurst SF, Reiss E. Competitive binding inhibition enzyme-linked immunosorbent assay that uses the secreted aspartyl proteinase of Candida albicans as an antigenic marker for diagnosis of disseminated candidiasis. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2003; 10:835-48. [PMID: 12965914 PMCID: PMC193877 DOI: 10.1128/cdli.10.5.835-848.2003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2003] [Revised: 03/18/2003] [Accepted: 06/23/2003] [Indexed: 11/20/2022]
Abstract
The secreted aspartyl proteinases (Saps) of Candida albicans have been implicated as virulence factors associated with adherence and tissue invasion. The potential use of proteinases as markers of invasive candidiasis led us to develop a competitive binding inhibition enzyme-linked immunosorbent assay (ELISA) to detect Sap in clinical specimens. Daily serum and urine specimens were collected from rabbits that had been immunosuppressed with cyclophosphamide and cortisone acetate and infected intravenously with 10(7) C. albicans blastoconidia. Disseminated infection was confirmed by organ culture and histopathology. Although ELISA inhibition was observed when serum specimens from these rabbits were used, more significant inhibition, which correlated with disease progression, occurred when urine specimens were used. Urine collected as early as 1 day after infection resulted in significant ELISA inhibition (mean inhibition +/- standard error [SE] compared with preinfection control urine, 15.7% +/- 2.7% [P < 0.01]), and inhibition increased on days 2 through 5 (29.4% +/- 4.8% to 44.5% +/- 3.5% [P < 0.001]). Urine specimens from immunosuppressed rabbits infected intravenously with Candida tropicalis, Candida parapsilosis, Candida krusei, Cryptococcus neoformans, Aspergillus fumigatus, or Staphylococcus aureus were negative in the assay despite culture-proven dissemination. Nonimmunosuppressed rabbits receiving oral tetracycline and gentamicin treatment were given 2 x 10(8) C. albicans blastoconidia orally or intraurethrally to establish colonization of the gastrointestinal tract or bladder, respectively, without systemic dissemination; urine specimens from these rabbits also gave negative ELISA results. Dissemination to the kidney and spleen occurred in one rabbit challenged by intragastric inoculation, and urine from this rabbit demonstrated significant inhibition in the ELISA (mean inhibition +/- SE by day 3 after infection, 32.9% +/- 2.7% [P < 0.001]). The overall test sensitivity was 83%, the specificity was 92%, the positive predictive value was 84%, the negative predictive value was 91%, and the efficiency was 89% (166 urine samples from 33 rabbits tested). The specificity, positive predictive value, and efficiency could be increased to 97, 95, and 92%, respectively, if at least two positive test results were required for a true positive designation. The ELISA was sensitive and specific for the detection of Sap in urine specimens from rabbits with disseminated C. albicans infection, discriminated between colonization and invasive disease, reflected disease progression and severity, and has the potential to be a noninvasive means to diagnose disseminated candidiasis.
Collapse
Affiliation(s)
- Christine J Morrison
- Mycotic Diseases Branch, Division of Bacterial and Mycotic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
| | | | | |
Collapse
|
40
|
Polak A. Antifungal therapy--state of the art at the beginning of the 21st century. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2003; Spec No:59-190. [PMID: 12675476 DOI: 10.1007/978-3-0348-7974-3_4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The most relevant information on the present state of the art of antifungal chemotherapy is reviewed in this chapter. For dermatomycoses a variety of topical antifungals are available, and safe and efficacious systemic treatment, especially with the fungicidal drug terbinafine, is possible. The duration of treatment can be drastically reduced. Substantial progress in the armamentarium of drugs for invasive fungal infections has been made, and a new class of antifungals, echinocandins, is now in clinical use. The following drugs in oral and/or intravenous formulations are available: the broad spectrum polyene amphotericin B with its new "clothes"; the sterol biosynthesis inhibitors fluconazole, itraconazole, and voriconazole; the glucan synthase inhibitor caspofungin; and the combination partner flucytosine. New therapy schedules have been studied; combination therapy has found a significant place in the treatment of severely compromised patients, and the field of prevention and empiric therapy is fast moving. Guidelines exist nowadays for the treatment of various fungal diseases and maintenance therapy. New approaches interfering with host defenses or pathogenicity of fungal cells are being investigated, and molecular biologists are looking for new targets studying the genomics of pathogenic fungi.
Collapse
|
41
|
Rogers PD, Barker KS. Evaluation of differential gene expression in fluconazole-susceptible and -resistant isolates of Candida albicans by cDNA microarray analysis. Antimicrob Agents Chemother 2002; 46:3412-7. [PMID: 12384344 PMCID: PMC128735 DOI: 10.1128/aac.46.11.3412-3417.2002] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The opportunistic fungal pathogen Candida albicans is the major causative agent of oropharyngeal candidiasis (OPC) in AIDS. The development of azoles, such as fluconazole, for the treatment of OPC has proven effective except in cases where C. albicans develops resistance to fluconazole during the course of treatment. In the present study, we used microarray technology to examine differences in gene expression from a fluconazole-susceptible and a fluconazole-resistant well-characterized, clinically obtained matched set of C. albicans isolates to identify genes which are differentially expressed in association with azole resistance. Among genes found to be differentially expressed were those involved in amino acid and carbohydrate metabolism; cell stress, cell wall maintenance; lipid, fatty acid, and sterol metabolism; and small molecule transport. In addition to CDR1, which has previously been demonstrated to be associated with azole resistance, the drug resistance gene RTA3, the ergosterol biosynthesis gene ERG2, and the cell stress genes CRD2, GPX1, and IFD5 were found to be upregulated. Several genes, such as the mitochondrial aldehyde dehydrogenase gene ALD5, the glycosylphosphatidylinositol synthesis gene GPI1, and the iron transport genes FET34 and FTR2 were found to be downregulated. Further study of these differentially regulated genes is warranted to evaluate how they may be involved in azole resistance. In addition to these novel findings, we demonstrate the utility of microarray analysis for studying the molecular mechanisms of drug resistance in pathogenic organisms.
Collapse
Affiliation(s)
- P David Rogers
- Departments of Clinical Pharmacy. Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA.
| | | |
Collapse
|
42
|
Ripeau JS, Aumont F, Belhumeur P, Ostrosky-Zeichner L, Rex JH, de Repentigny L. Effect of the echinocandin caspofungin on expression of Candida albicans secretory aspartyl proteinases and phospholipase in vitro. Antimicrob Agents Chemother 2002; 46:3096-100. [PMID: 12183282 PMCID: PMC127410 DOI: 10.1128/aac.46.9.3096-3100.2002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although the echinocandin caspofungin primarily inhibits the synthesis of cell wall 1,3-beta-D-glucan, its fungicidal activity could also potentially perturb the expression of virulence factors involved in the ability of Candida albicans to cause infection. Expression of the C. albicans secretory aspartyl proteinase (SAP) and phospholipase B (PLB) virulence genes was determined by reverse transcription-PCR after the addition of caspofungin to cells grown for 15 h in Sabouraud dextrose broth. In cells that remained viable, expression of SAP1 to SAP3, SAP7 to SAP9, and PLB1 was unaltered after exposure to fungicidal concentrations (4 to 16 micro g/ml) of caspofungin over a period of 7 h. However, expression of SAP5 increased steadily beginning 1 h after exposure to caspofungin. These results indicate that caspofungin is rapidly fungicidal against C. albicans, before any suppression of SAP or PLB1 gene expression can occur.
Collapse
Affiliation(s)
- Jean-Sébastien Ripeau
- Department of Microbiology and Immunology, Faculty of Medicine, University of Montreal, Quebec, Canada
| | | | | | | | | | | |
Collapse
|
43
|
Latgé JP, Calderone R. Host-microbe interactions: fungi invasive human fungal opportunistic infections. Curr Opin Microbiol 2002; 5:355-8. [PMID: 12160852 DOI: 10.1016/s1369-5274(02)00343-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Jean-Paul's research interest is focused on the analysis of the structure and biosynthesis of the cell wall of Aspergillus fumigatus and its interaction with the host. The A. fumigatus genome will now be used to understand multifactorial systems such as fungal virulence of an opportunistic fungus in an immunocompromised host and assembly and regulation of cell wall polymer rearrangement under the control of the environment.
Collapse
|
44
|
Borg-von Zepelin M, Niederhaus T, Gross U, Seibold M, Monod M, Tintelnot K. Adherence of different Candida dubliniensis isolates in the presence of fluconazole. AIDS 2002; 16:1237-44. [PMID: 12045488 DOI: 10.1097/00002030-200206140-00005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The recently described yeast species Candida dubliniensis is closely related to C. albicans and has been recovered predominantly from the oral cavities of HIV-infected individuals and AIDS patients who are often receiving fluconazole as prophylactic or therapeutic treatment for oropharyngeal candidiasis. Like C. albicans, C. dubliniensis secretes aspartic proteinases which in C. albicans have been shown to be involved in adherence. OBJECTIVE To explain the increasing prevalence of C. dubliniensis in AIDS patients and to investigate the virulence factors of this yeast. METHODS An in vitro assay was developed to compare the adherence to epithelial cells of C. dubliniensis from HIV-patients with that of C. albicans. RESULTS All C. albicans isolates adhered better than the 22 C. dubliniensis isolates. In the presence of fluconazole, the C. dubliniensis isolates tested showed increased adherence as compared with controls without fluconazole. In contrast, all C. albicans isolates decreased in adherence to epithelial cells in the presence of fluconazole independently of their in vitro susceptibility to this drug. Proteinase antigens are present on the surface of C. dubliniensis cells adherent to epithelial target cells. In the presence of fluconazole this proteinase antigen was more strongly expressed. CONCLUSION Increased adherence of C. dubliniensis strains in the presence of fluconazole could explain its high recovery rate from HIV-positive patients in recent years. The induction of proteinase secretion in the presence of fluconazole found for most of the C. dubliniensis isolates could be one of the factors involved in adherence.
Collapse
|
45
|
Angiolella L, Micocci MM, D'Alessio S, Girolamo A, Maras B, Cassone A. Identification of major glucan-associated cell wall proteins of Candida albicans and their role in fluconazole resistance. Antimicrob Agents Chemother 2002; 46:1688-94. [PMID: 12019077 PMCID: PMC127269 DOI: 10.1128/aac.46.6.1688-1694.2002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Identification of major glucan-associated proteins (GAPs) of the cell wall of a number of Candida albicans isolates susceptible or resistant to fluconazole (FLC) was addressed by direct sequencing of the protein bands resolved by unidimensional gel electrophoresis. Changes in the GAP compositions of the different strains grown in the presence of the drug were also investigated. In the FLC-susceptible strains, the major (more abundant) GAPs were enolase (46 kDa), two isoforms of phosphoglyceromutase (32 and 29 kDa), and two beta-(1-3)-exoglucanases (44 and 34 kDa), one of which (the 34-kDa component) was glycosylated. When these strains were grown in the presence of FLC there were substantial decreases in the intensities of the two enzymes of the glycolytic pathway (enolase and the phosphoglyceromutases), which were apparently replaced by enhancement of the exoglucanase constituents, particularly the 44-kDa one. This GAP pattern closely mimicked that observed in the FLC-resistant strains whether they were grown in the presence or in the absence of the drug. Both the enolase and the exoglucanase constituents were detected in the culture supernatants of FLC-treated cells, together with substantial amounts of highly glycosylated, probably mannoprotein secretory material, suggesting that FLC may cause marked alterations of GAP incorporation into the cell wall. Altogether, we were able to identify all major GAP constituents and monitor their distributions in the cell wall of C. albicans during treatment with FLC. The near equivalence of the GAP profile for the FLC-susceptible strain grown in the presence of FLC to that for the FLC-resistant strain suggests that the effects of the drug on GAPs may be stably incorporated into the cell wall of the fungus upon acquisition of resistance.
Collapse
|
46
|
Imbert C, Rodier MH, Daniault G, Jacquemin JL. Influence of sub-inhibitory concentrations of conventional antifungals on metabolism of Candida albicans and on its adherence to polystyrene and extracellular matrix proteins. Med Mycol 2002; 40:123-9. [PMID: 12058724 DOI: 10.1080/mmy.40.2.123.129] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Five antifungal agents with different mechanisms of action were compared for their ability to affect mitochondrial dehydrogenase activity and adherence capacity of Candida albicans to polystyrene and extracellular matrix proteins. Only amphotericin B inhibited mitochondrial dehydrogenase activity when the culture medium was supplemented with galactose. 5-Fluorocytosine and terbinafine did not affect this activity, whereas itraconazole and fluconazole improved it. Furthermore, in these experimental conditions, the effect of sub-inhibitory concentrations of antifungals on adherence was dependent on the tested antifungal and the adherence surface: amphotericin B inhibited adherence to polystyrene and fibrinogen, but improved adherence to extracellular matrix. For all surfaces tested, when culture medium was supplemented with galactose, fluorocytosine did not affect adherence, and itraconazole, fluconazole and terbinafine inhibited adherence. Our results also confirmed the influence of the carbohydrates: sub-minimum inhibitory concentrations (MIC) of itraconazole increased or did not modify the mitochondrial metabolism of yeasts when the culture medium was supplemented with galactose, but this antifungal always decreased mitochondrial metabolism when the culture medium was supplemented with glucose. These data indicate that antifungals used below their MIC values can have various effects. It is important to distinguish the effects of antifungals on the metabolism of C. albicans from effects on its adherence capacity. The former effects are linked to the viability of the yeast and the latter depends on the colonization of cellular as opposed to inert surfaces.
Collapse
Affiliation(s)
- C Imbert
- Laboratoire de Parasitologie et Mycologie Médicales, Centre Hospitalier Universitaire La Milétrie, Poitiers, France.
| | | | | | | |
Collapse
|
47
|
Staib P, Wirsching S, Strauss A, Morschhäuser J. Gene regulation and host adaptation mechanisms in Candida albicans. Int J Med Microbiol 2001; 291:183-8. [PMID: 11437340 DOI: 10.1078/1438-4221-00114] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The yeast Candida albicans is a harmless member of the normal microflora on the mucosal surfaces of most healthy persons, but it can cause severe opportunistic infections in immunosuppressed patients. To become a successful human commensal and pathogen, C. albicans has evolved host adaptation mechanisms on different levels. The regulated expression of virulence and other genes in response to environmental signals allows an optimal adaptation to new host niches during the course of an infection. In addition, C. albicans is able to switch between different cell types in a reversible and apparently random fashion. Phenotypic switching involves the coordinated regulation of phase-specific genes, and the resulting generation of selected, pre-programmed cell types may represent an additional strategy to adapt to certain host environments. Finally, C. albicans produces genetically altered variants at a high rate. This microevolution ensures survival when the pathogen encounters new adverse conditions, as exemplified by the development of stable drug-resistant variants under the selection pressure caused by antimycotic therapy. Thus, rather than the possession of single dominant virulence factors, it is its remarkable versatility that makes C. albicans the most important fungal pathogen of humans.
Collapse
Affiliation(s)
- P Staib
- Zentrum für Infektionsforschung, Universität Würzburg, Germany
| | | | | | | |
Collapse
|
48
|
|