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Rajkumaar J, Mathew MG. Association of severe early childhood caries with salivary ferritin. J Family Med Prim Care 2020; 9:3991-3993. [PMID: 33110799 PMCID: PMC7586573 DOI: 10.4103/jfmpc.jfmpc_9_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 03/11/2020] [Accepted: 04/03/2020] [Indexed: 01/11/2023] Open
Abstract
Aim: To evaluate salivary ferritin levels in children with severe early childhood caries (ECC). Materials and Methods: One hundred twenty participants were split into a study group that consisted of 60 children with severe ECC (dmft ≥5) and a control group that was free of caries. Both groups were age and gender-matched. Saliva was collected from both groups. Salivary ferritin was assessed using chemiluminescence microparticle immunoassay. The data obtained were statistically analyzed. Results: Salivary ferritin levels were higher in children with severe ECC (159.53 ± 18.65 μg/dl) compared to children with no caries (92.16 ± 12.91 μg/dl) and a highly significant statistical difference was seen (P < 0.001). Conclusions: Salivary ferritin levels were high with children having severe ECC.
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Affiliation(s)
- Jagadish Rajkumaar
- Department of Pedodontics and Preventive Dentistry, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India
| | - Mebin George Mathew
- Department of Pedodontics and Preventive Dentistry, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India
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52
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König A, Müller R, Mogavero S, Hube B. Fungal factors involved in host immune evasion, modulation and exploitation during infection. Cell Microbiol 2020; 23:e13272. [PMID: 32978997 DOI: 10.1111/cmi.13272] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/20/2020] [Accepted: 07/26/2020] [Indexed: 01/09/2023]
Abstract
Human and plant pathogenic fungi have a major impact on public health and agriculture. Although these fungi infect very diverse hosts and are often highly adapted to specific host niches, they share surprisingly similar mechanisms that mediate immune evasion, modulation of distinct host targets and exploitation of host nutrients, highlighting that successful strategies have evolved independently among diverse fungal pathogens. These attributes are facilitated by an arsenal of fungal factors. However, not a single molecule, but rather the combined effects of several factors enable these pathogens to establish infection. In this review, we discuss the principles of human and plant fungal pathogenicity mechanisms and discuss recent discoveries made in this field.
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Affiliation(s)
- Annika König
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute, Jena, Germany
| | - Rita Müller
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute, Jena, Germany
| | - Selene Mogavero
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute, Jena, Germany.,Center for Sepsis Control and Care, University Hospital Jena, Jena, Germany.,Institute of Microbiology, Friedrich Schiller University, Jena, Germany
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53
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Martínez-Pastor MT, Puig S. Adaptation to iron deficiency in human pathogenic fungi. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118797. [PMID: 32663505 DOI: 10.1016/j.bbamcr.2020.118797] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/13/2020] [Accepted: 07/05/2020] [Indexed: 02/08/2023]
Abstract
Iron is an essential micronutrient for virtually all eukaryotic organisms and plays a central role during microbial infections. Invasive fungal diseases are associated with strikingly high rates of mortality, but their impact on human health is usually underestimated. Upon a fungal infection, hosts restrict iron availability in order to limit the growth and virulence of the pathogen. Here, we use two model yeasts, Saccharomyces cerevisiae and Schizosaccharomyces pombe, to delve into the response to iron deficiency of human fungal pathogens, such as Candida glabrata, Candida albicans, Aspergillus fumigatus and Cryptococcus neoformans. Fungi possess common and species-specific mechanisms to acquire iron and to control the response to iron limitation. Upon iron scarcity, fungi activate a wide range of elegant strategies to capture and import exogenous iron, mobilize iron from intracellular stores, and modulate their metabolism to economize and prioritize iron utilization. Hence, iron homeostasis genes represent remarkable virulence factors that can be used as targets for the development of novel antifungal treatments.
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Affiliation(s)
| | - Sergi Puig
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain.
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54
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Tripathi A, Liverani E, Tsygankov AY, Puri S. Iron alters the cell wall composition and intracellular lactate to affect Candida albicans susceptibility to antifungals and host immune response. J Biol Chem 2020; 295:10032-10044. [PMID: 32503842 DOI: 10.1074/jbc.ra120.013413] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/27/2020] [Indexed: 12/19/2022] Open
Abstract
Fungal pathogen Candida albicans has a complex cell wall consisting of an outer layer of mannans and an inner layer of β-glucans and chitin. The fungal cell wall is the primary target for antifungals and is recognized by host immune cells. Environmental conditions such as carbon sources, pH, temperature, and oxygen tension can modulate the fungal cell wall architecture. Cellular signaling pathways, including the mitogen-activated protein kinase (MAPK) pathways, are responsible for sensing environmental cues and mediating cell wall alterations. Although iron has recently been shown to affect β-1,3-glucan exposure on the cell wall, we report here that iron changes the composition of all major C. albicans cell wall components. Specifically, high iron decreased the levels of mannans (including phosphomannans) and chitin; and increased β-1,3-glucan levels. These changes increased the resistance of C. albicans to cell wall-perturbing antifungals. Moreover, high iron cells exhibited adequate mitochondrial functioning; leading to a reduction in accumulation of lactate that signals through the transcription factor Crz1 to induce β-1,3-glucan masking in C. albicans We show here that iron-induced changes in β-1,3-glucan exposure are lactate-dependent; and high iron causes β-1,3-glucan exposure by preventing lactate-induced, Crz1-mediated inhibition of activation of the fungal MAPK Cek1. Furthermore, despite exhibiting enhanced antifungal resistance, high iron C. albicans cells had reduced survival upon phagocytosis by macrophages. Our results underscore the role of iron as an environmental signal in multiple signaling pathways that alter cell wall architecture in C. albicans, thereby affecting its survival upon exposure to antifungals and host immune response.
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Affiliation(s)
- Aparna Tripathi
- Oral Microbiome Research Laboratory, Department of Oral Health Sciences, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania, USA
| | - Elisabetta Liverani
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Temple University Hospital, Philadelphia, Pennsylvania, USA
| | - Alexander Y Tsygankov
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Temple University Hospital, Philadelphia, Pennsylvania, USA.,Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
| | - Sumant Puri
- Oral Microbiome Research Laboratory, Department of Oral Health Sciences, Kornberg School of Dentistry, Temple University, Philadelphia, Pennsylvania, USA
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55
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Mba IE, Nweze EI. Mechanism of Candida pathogenesis: revisiting the vital drivers. Eur J Clin Microbiol Infect Dis 2020; 39:1797-1819. [PMID: 32372128 DOI: 10.1007/s10096-020-03912-w] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 04/17/2020] [Indexed: 12/14/2022]
Abstract
Candida is the most implicated fungal pathogen in the clinical setting. Several factors play important roles in the pathogenesis of Candida spp. Multiple transcriptional circuits, morphological and phenotypic switching, biofilm formation, tissue damaging extracellular hydrolytic enzymes, metabolic flexibility, genome plasticity, adaptation to environmental pH fluctuation, robust nutrient acquisition system, adherence and invasions (mediated by adhesins and invasins), heat shock proteins (HSPs), cytolytic proteins, escape from phagocytosis, evasion from host immune system, synergistic coaggregation with resident microbiota, resistance to antifungal agents, and the ability to efficiently respond to multiple stresses are some of the major pathogenic determinants of Candida species. The existence of multiple connections, in addition to the interactions and associations among all of these factors, are distinctive features that play important roles in the establishment of Candida infections. This review describes all the underlying factors and mechanisms involved in Candida pathogenesis by evaluating pathogenic determinants of Candida species. It reinforces the already available pool of data on the pathogenesis of Candida species by providing a clear and simplified understanding of the most important factors implicated in the pathogenesis of Candida species. The Candida pathogenesis network, an illustration linking all the major determinants of Candida pathogenesis, is also presented. Taken together, they will further improve our current understanding of how these factors modulate virulence and consequent infection(s). Development of new antifungal drugs and better therapeutic approaches to candidiasis can be achieved in the near future with continuing progress in the understanding of the mechanisms of Candida pathogenesis.
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56
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Muthamil S, Prasath KG, Priya A, Precilla P, Pandian SK. Global proteomic analysis deciphers the mechanism of action of plant derived oleic acid against Candida albicans virulence and biofilm formation. Sci Rep 2020; 10:5113. [PMID: 32198447 PMCID: PMC7083969 DOI: 10.1038/s41598-020-61918-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 03/02/2020] [Indexed: 01/04/2023] Open
Abstract
Candida albicans is a commensal fungus in humans, mostly found on the mucosal surfaces of the mouth, gut, vagina and skin. Incidence of ever increasing invasive candidiasis in immunocompromised patients, alarming occurrence of antifungal resistance and insufficient diagnostic methods demand more focused research into C. albicans pathogenicity. Consequently, in the present study, oleic acid from Murraya koenigii was shown to have the efficacy to inhibit biofilm formation and virulence of Candida spp. Results of in vitro virulence assays and gene expression analysis, impelled to study the protein targets which are involved in the molecular pathways of C. albicans pathogenicity. Proteomic studies of differentially expressed proteins reveals that oleic acid induces oxidative stress responses and mainly targets the proteins involved in glucose metabolism, ergosterol biosynthesis, lipase production, iron homeostasis and amino acid biosynthesis. The current study emphasizes anti-virulent potential of oleic acid which can be used as a therapeutic agent to treat Candida infections.
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Affiliation(s)
- Subramanian Muthamil
- Department of Biotechnology Science Campus Alagappa University Karaikudi, 630 003, Tamil Nadu, India
| | - Krishnan Ganesh Prasath
- Department of Biotechnology Science Campus Alagappa University Karaikudi, 630 003, Tamil Nadu, India
| | - Arumugam Priya
- Department of Biotechnology Science Campus Alagappa University Karaikudi, 630 003, Tamil Nadu, India
| | - Pitchai Precilla
- Department of Biotechnology Science Campus Alagappa University Karaikudi, 630 003, Tamil Nadu, India
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57
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Duval C, Macabiou C, Garcia C, Lesuisse E, Camadro J, Auchère F. The adaptive response to iron involves changes in energetic strategies in the pathogen Candida albicans. Microbiologyopen 2020; 9:e970. [PMID: 31788966 PMCID: PMC7002100 DOI: 10.1002/mbo3.970] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/22/2019] [Accepted: 10/29/2019] [Indexed: 12/19/2022] Open
Abstract
Candida albicans is an opportunist pathogen responsible for a large spectrum of infections, from superficial mycosis to systemic diseases known as candidiasis. Its ability to grow in different morphological forms, such as yeasts or filamentous hyphae, contributes to its survival in diverse microenvironments. Iron uptake has been associated with virulence, and C. albicans has developed elaborate strategies for acquiring iron from its host. In this work, we analyze the metabolic changes in response to changes in iron content in the growth medium and compare C. albicans adaptation to the presence or absence of iron. Functional and morphological studies, correlated to a quantitative proteomic analysis, were performed to assess the specific pathways underlying the response to iron, both in the yeast and filamentous forms. Overall, the results show that the adaptive response to iron is associated with a metabolic remodeling affecting the energetic pathways of the pathogen. This includes changes in the thiol-dependent redox status, the activity of key mitochondrial enzymes and the respiratory chain. Iron deficiency stimulates bioenergetic pathways, whereas iron-rich condition is associated with greater biosynthetic needs, particularly in filamentous forms. Moreover, we found that C. albicans yeast cells have an extraordinary capability to adapt to changes in environmental conditions.
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Affiliation(s)
- Celia Duval
- Laboratoire MitochondriesMétaux et Stress OxydantInstitut Jacques MonodUMR 7592Université Paris‐Diderot/CNRS (USPC)ParisFrance
| | - Carole Macabiou
- Laboratoire MitochondriesMétaux et Stress OxydantInstitut Jacques MonodUMR 7592Université Paris‐Diderot/CNRS (USPC)ParisFrance
| | - Camille Garcia
- Plateforme Protéomique structurale et fonctionnelle/Spectrométrie de masseInstitut Jacques MonodUMR 7592Université Paris‐Diderot/CNRS (USPC)ParisFrance
| | - Emmanuel Lesuisse
- Laboratoire MitochondriesMétaux et Stress OxydantInstitut Jacques MonodUMR 7592Université Paris‐Diderot/CNRS (USPC)ParisFrance
| | - Jean‐Michel Camadro
- Laboratoire MitochondriesMétaux et Stress OxydantInstitut Jacques MonodUMR 7592Université Paris‐Diderot/CNRS (USPC)ParisFrance
| | - Françoise Auchère
- Laboratoire MitochondriesMétaux et Stress OxydantInstitut Jacques MonodUMR 7592Université Paris‐Diderot/CNRS (USPC)ParisFrance
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58
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Ror S, Panwar SL. Sef1-Regulated Iron Regulon Responds to Mitochondria-Dependent Iron-Sulfur Cluster Biosynthesis in Candida albicans. Front Microbiol 2019; 10:1528. [PMID: 31354649 PMCID: PMC6630100 DOI: 10.3389/fmicb.2019.01528] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 06/18/2019] [Indexed: 11/13/2022] Open
Abstract
Iron homeostasis mechanisms allow the prime commensal-pathogen Candida albicans to cope with the profound shift in iron levels in the mammalian host. The regulators, Sef1 and Sfu1 influence activation and repression of genes required for iron uptake and acquisition by inducing the expression of iron regulon genes in iron-deplete conditions and inactivating them in iron-replete condition. Our study for the first time shows that C. albicans coordinates the activation of the iron regulon with the mitochondrial use of iron for Fe–S cluster biosynthesis, a cellular process that is connected to cellular iron metabolism. We took advantage of a mutant defective in mitochondrial biogenesis (fzo1Δ/Δ) to assess the aforesaid link as this mutant exhibited sustained expression of the Sef1 iron regulon, signifying an iron-starved state in the mutant. Our analysis demonstrates that mitochondrion is pivotal for regulation of Fe–S cluster synthesis such that the disruption of this cellular process in fzo1Δ/Δ cells lead to excessive mitochondrial iron accumulation and reduced activity of the Fe–S cluster-containing enzyme aconitase. Sef1 responds to defective Fe–S cluster synthesis by regulated changes in its subcellular localization; it was retained in the nucleus resulting in the induced expression of the iron regulon. We predict that the mitochondrial Fe–S assembly generates a molecule that is critical for ensuring iron-responsive transcriptional activation of the Sef1 regulon. All told, our data marks Fe–S biogenesis as a mechanism that meshes cellular iron procurement with mitochondrial iron metabolism resulting in regulating the Sef1 regulon in C. albicans.
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Affiliation(s)
- Shivani Ror
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Sneh Lata Panwar
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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59
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Fillinger RJ, Anderson MZ. Seasons of change: Mechanisms of genome evolution in human fungal pathogens. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2019; 70:165-174. [PMID: 30826447 DOI: 10.1016/j.meegid.2019.02.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 02/23/2019] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
Fungi are a diverse kingdom of organisms capable of thriving in various niches across the world including those in close association with multicellular eukaryotes. Fungal pathogens that contribute to human disease reside both within the host as commensal organisms of the microbiota and the environment. Their niche of origin dictates how infection initiates but also places specific selective pressures on the fungal pathogen that contributes to its genome organization and genetic repertoire. Recent efforts to catalogue genomic variation among major human fungal pathogens have unveiled evolutionary themes that shape the fungal genome. Mechanisms ranging from large scale changes such as aneuploidy and ploidy cycling as well as more targeted mutations like base substitutions and gene copy number variations contribute to the evolution of these species, which are often under multiple competing selective pressures with their host, environment, and other microbes. Here, we provide an overview of the major selective pressures and mechanisms acting to evolve the genome of clinically important fungal pathogens of humans.
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Affiliation(s)
- Robert J Fillinger
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210, USA
| | - Matthew Z Anderson
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210, USA; Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.
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