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Microbial Biotechnology Feb 2022Trichophyton rubrum is responsible for the majority of dermatophytosis. Current systemic and topical antifungals against dermatophytosis are often tedious and sometimes...
Trichophyton rubrum is responsible for the majority of dermatophytosis. Current systemic and topical antifungals against dermatophytosis are often tedious and sometimes unsatisfactory. Antimicrobial photodynamic therapy (aPDT) is a non-invasive alternative suitable for the treatment of superficial fungal infections. This work investigated the photodynamic inactivation efficacy and effects of aloe-emodin (AE), a natural photosensitizer (PS) against T. rubrum microconidia in vitro, and evaluated the treatment effects of AE-mediated aPDT for T. rubrum-caused tinea corporis in vivo and tinea unguium ex vivo. The photodynamic antimicrobial efficacy of AE on T. rubrum microconidia was evaluated by MTT assay. The inhibition effect of AE-mediated aPDT on growth of T. rubrum was studied. Intracellular location of AE, damage induced by AE-mediated aPDT on cellular structure and surface of microconidia and generation of intracellular ROS were investigated by microscopy and flow cytometry. The therapeutic effects of AE-mediated aPDT against dermatophytosis were assessed in T. rubrum-caused tinea corporis guinea pig model and tinea unguium ex vivo model. AE-mediated aPDT effectively inactivated T. rubrum microconidia in a light energy dose-dependent manner and exhibited strong inhibitory effect on growth of T. rubrum. Microscope images indicated that AE is mainly targeted to the organelles and caused damage to the cytoplasm of microconidia after irradiation through generation of abundant intracellular ROS. AE-mediated aPDT demonstrated effective therapeutic effects for T. rubrum-caused tinea corporis on guinea pig model and tinea unguium in ex vivo model. The results obtained suggest that AE is a potential PS for the photodynamic treatment of dermatophytosis caused by T. rubrum, but its permeability in skin and nails needs to be improved.
Topics: Aloe; Animals; Anti-Bacterial Agents; Anti-Infective Agents; Arthrodermataceae; Emodin; Guinea Pigs; Onychomycosis; Photochemotherapy; Photosensitizing Agents; Reactive Oxygen Species; Tinea; Trichophyton
PubMed: 34165875
DOI: 10.1111/1751-7915.13875 -
Journal of Fungi (Basel, Switzerland) Jan 2022Terbinafine resistance in species has emerged and appears to be increasing. A new EUCAST susceptibility testing method and tentative ECOFFs were recently proposed for ....
Terbinafine resistance in species has emerged and appears to be increasing. A new EUCAST susceptibility testing method and tentative ECOFFs were recently proposed for . Terbinafine resistance and target gene mutations were detected in 16 Danish isolates in 2013-2018. In this study, samples/isolates submitted for dermatophyte susceptibility testing 2019-2020 were examined. Species identification (ITS sequencing for species complex (SC) isolates), EUCAST MICs and squalene epoxidase (SQLE) profiles were obtained. Sixty-three isolates from 59 patients were included. accounted for 81% and SC for 19%. Approximately 60% of and SC isolates were terbinafine non-wildtype and/or had known/novel SQLE mutations with possible implications for terbinafine MICs. All infections with terbinafine-resistant SC isolates were caused by . Compared to 2013-2018, the number of patients with terbinafine-resistant isolates increased. For , this is partly explained by an increase in number of requests for susceptibility testing. Terbinafine-resistant was first detected in 2018, but accounted for 19% of resistance (4 of 21 patients) in 2020. In conclusion, terbinafine resistance is an emerging problem in Denmark. Population based studies are warranted and susceptibility testing is highly relevant in non-responding cases.
PubMed: 35205904
DOI: 10.3390/jof8020150 -
BMC Genomics Dec 2018Trichophyton rubrum (T. rubrum) is an important model organism of dermatophytes, which are the most common fungal pathogens worldwide. Despite the severity and...
BACKGROUND
Trichophyton rubrum (T. rubrum) is an important model organism of dermatophytes, which are the most common fungal pathogens worldwide. Despite the severity and prevalence of the infection caused by these pathogens, current therapies are not sufficient. MicroRNA (miRNA) is a class of small noncoding RNAs that are key factors in the regulation of gene expression. These miRNAs are reported to be highly conserved in different organisms and are involved in various essential cellular processes. In this study, we performed an integrated analysis of microRNA-like RNAs (milRNAs) and mRNAs between conidial and mycelial stages to investigate the roles of milRNAs in regulating the expression of target genes in T. rubrum.
RESULTS
A total of 158 conserved milRNAs and 12 novel milRNAs were identified in our study, corresponding to 5470 target genes, which were involved in various essential biological pathways. In addition, 137 target genes corresponding to 21 milRNAs were concurrent differentially expressed between the conidial and mycelial stages. Among these 137 target genes, 64 genes showed the opposite trend to their corresponding milRNAs in expression difference between the two stages, indicating possible negative regulation. Furthermore, 46% of differentially expressed target genes are involved in transcription, transcriptional and post-transcriptional regulation. Our results indicate that milRNAs might associate with other regulatory elements to control gene expression at both transcriptional and post-transcriptional level.
CONCLUSIONS
This study provides the first analysis of milRNA expression profile in T. rubrum as well as dermatophytes in general. The results revealed the roles of milRNAs in regulating gene expression between the two major growth stages of this fungus. Our study deepens our understanding of T. rubrum and will serve as a foundation for further investigations to combat this fungus.
Topics: Gene Expression Regulation, Fungal; MicroRNAs; RNA, Fungal; RNA, Messenger; Sequence Analysis, RNA; Trichophyton
PubMed: 30547762
DOI: 10.1186/s12864-018-5316-3 -
The Journal of Investigative Dermatology Oct 2019Despite the threatening incidence of dermatophytosis, information is still lacking about the consequences of infection on epidermal barrier functions and about the... (Review)
Review
Despite the threatening incidence of dermatophytosis, information is still lacking about the consequences of infection on epidermal barrier functions and about the keratinocyte responses that alert immune components. To identify the mechanisms involved, arthroconidia of the anthropophilic dermatophyte Trichophyton rubrum were prepared to infect reconstructed human epidermis (RHE) in vitro. Integrity of the barrier was monitored during infection by measurements of transepithelial electrical resistance and dye-permeation through the RHE. Expression and release of pro-inflammatory cytokines and antimicrobial peptides by keratinocytes inserted into the RHE were assessed, respectively, by quantitative reverse transcriptase-PCR (to analyze mRNA content in tissue extracts) and by ELISA (to detect proteins in culture media). Results reveal that infection by T. rubrum is responsible for disruption of the epidermal barrier, including loss of functional tight junctions. It additionally causes simultaneous expression and release of cytokines and antimicrobial peptides by keratinocytes. Potential involvement of the p38 mitogen-activated protein kinase signaling pathway was evaluated during infection by targeted inhibition of its activity. Intriguingly, among several p38 mitogen-activated protein kinase inhibitors, PD169316 alone was able to inhibit growth of T. rubrum on Sabouraud agar and to suppress the process of infection on RHE. This suggests that PD169316 acts on a specific target in dermatophytes themselves.
Topics: Arthrodermataceae; Culture Media; Cytokines; Epidermal Cells; Humans; Imidazoles; In Vitro Techniques; Keratinocytes; Microscopy, Electron; RNA, Messenger; Real-Time Polymerase Chain Reaction; Reference Values; Sensitivity and Specificity; Tinea
PubMed: 30986374
DOI: 10.1016/j.jid.2019.03.1147 -
Journal of Fungi (Basel, Switzerland) Aug 2022is responsible for several superficial human mycoses. Novel strategies aimed at controlling this pathogen are being investigated. The objective of this study was to...
is responsible for several superficial human mycoses. Novel strategies aimed at controlling this pathogen are being investigated. The objective of this study was to evaluate the antifungal activity of the antidepressant sertraline (SRT), either alone or in combination with caspofungin (CASP). We calculated the minimum inhibitory concentrations of SRT and CASP against . Interactions between SRT and CASP were evaluated using a broth microdilution chequerboard. We assessed the differential expression of cultivated in the presence of SRT or combinations of SRT and CASP. We used MTT and violet crystal assays to compare the effect of SRT alone on biofilms with that of the synergistic combination of SRT and CASP. A human nail infection assay was performed. SRT alone, or in combination with CASP, exhibited antifungal activity against SRT targets genes involved in the biosyntheses of cell wall and ergosterol. Furthermore, the metabolic activity of the biofilm and its biomass were affected by SRT and the combination of SRT and CASP. SRT alone, or in combination, shows potential as an approach to minimise resistance and reduce virulence.
PubMed: 36012803
DOI: 10.3390/jof8080815 -
Journal of Fungi (Basel, Switzerland) Jan 2022Neutrophils are the first leukocytes recruited to the site of infection and are thought to be responsible for fungal elimination from the skin such as dermatophytes....
Neutrophils are the first leukocytes recruited to the site of infection and are thought to be responsible for fungal elimination from the skin such as dermatophytes. Neutrophils are able to secrete reactive oxygen species (ROS) and neutrophil extracellular traps (NETs) that can kill different fungi, including , spp., , and . However, NET production in response to , the main etiologic agent of dermatophytosis, has yet to be studied. We demonstrated that human neutrophils produce NETs against different morphotypes of in a dose-dependent manner and NET formation is dependent on ROS production. In addition, ROS production by human neutrophils in response to is dependent on NADPH oxidase, but not on fungal viability. NETs mediated killing of Collectively, these results demonstrate that was able to trigger the production of NETs, suggesting that these extracellular structures may represent an important innate immune effector mechanism controlling physiological response to infection.
PubMed: 35205902
DOI: 10.3390/jof8020147 -
Frontiers in Cellular and Infection... 2021Fungal infections represent a significant concern worldwide, contributing to human morbidity and mortality. Dermatophyte infections are among the most significant...
Fungal infections represent a significant concern worldwide, contributing to human morbidity and mortality. Dermatophyte infections are among the most significant mycoses, and appears to be the principal causative agent. Thus, an understanding of its pathophysiology is urgently required. Several lines of evidence have demonstrated that the APSES family of transcription factors (Asm1p, Phd1p, Sok2p, Efg1p, and StuA) is an important point of vulnerability in fungal pathogens and a potential therapeutic target. These transcription factors are unique to fungi, contributing to cell differentiation and adaptation to environmental cues and virulence. It has recently been demonstrated that StuA plays a pleiotropic role in dermatophyte pathophysiology. It was suggested that it functions as a mediator of crosstalk between different pathways that ultimately contribute to adaptive responses and fungal-host interactions. The complex regulation of StuA and its interaction pathways are yet to be unveiled. Thus, this study aimed to gain a deeper understanding of StuA-regulated processes in by assessing global gene expression following growth on keratin or glucose sources. The data showed the involvement of StuA in biological processes related to central carbon metabolism and glycerol catabolism, reactive oxygen species metabolism, and cell wall construction. Changes in carbohydrate metabolism may be responsible for the significant alteration in cell wall pattern and consequently in cell-cell interaction and adhesion. Loss of StuA led to impaired biofilm production and promoted proinflammatory cytokine secretion in a human keratinocyte cell line. We also observed the StuA-dependent regulation of catalase genes. Altogether, these data demonstrate the multitude of regulatory targets of StuA with a critical role in central metabolism that may ultimately trigger a cascade of secondary effects with substantial impact on fungal physiology and virulence traits.
Topics: Arthrodermataceae; Cell Adhesion; Fungal Proteins; Gene Expression Regulation, Fungal; Humans; Immunomodulation; Trichophyton
PubMed: 34169004
DOI: 10.3389/fcimb.2021.643659 -
Medical Mycology Journal 2023Multi-antifungal-resistant strains of Trichophyton indotineae and Trichophyton rubrum have been isolated in Japan. In the present study, we examined the in vitro...
Multi-antifungal-resistant strains of Trichophyton indotineae and Trichophyton rubrum have been isolated in Japan. In the present study, we examined the in vitro susceptibility of terbinafine (TRBF) -resistant isolates of T. indotineae and T. rubrum to efinaconazole (EFCZ) and luliconazole (LUCZ). In all isolates, the minimum inhibitory concentrations were ≥ 32 mg/l for TRBF, < 0.03 to 16 mg/l for itraconazole, < 0.03 to 16 mg/l for ravuconazole, < 0.03 to 0.5 mg/l for LUCZ, and < 0.03 to 4 mg/l for EFCZ. Of note, T. rubrum NUBS21012 and T. indotineae NUBS 19006 showed resistance to LUCZ and/or EFCZ unlike the other isolates.
Topics: Humans; Azoles; Terbinafine; Trichophyton; Drug Resistance, Fungal
PubMed: 36858630
DOI: 10.3314/mmj.22-00021 -
Iranian Journal of Microbiology Aug 2022Monitoring of contagious diseases is important to advance our knowledge of their epidemiology and to enable more impressive investigation and prevention efforts. This...
BACKGROUND AND OBJECTIVES
Monitoring of contagious diseases is important to advance our knowledge of their epidemiology and to enable more impressive investigation and prevention efforts. This study aimed to examine antifungal drug susceptibility and molecular analysis of clinical isolates of and in humans and cattle.
MATERIALS AND METHODS
A total of 400 patients and 500 cattle were evaluated in this study. Dermatophytosis was confirmed in cases by direct microscopy and culture methods. Antifungal drug susceptibility profiles, MIC, and MIC of isolates were determined using the broth microdilution method. Multiplex-PCR, RAPD PCR, and sequencing methods were used for the genetic analysis of virulence genes and the ITS1 and ITS2 regions, respectively.
RESULTS
A total of 175 patients and 120 cattle were diagnosed with dermatophytosis. Dermatophytes showed a remarkable rate (30%) of terbinafine resistance. showed lower susceptibility than (MIC =16 μg/mL). Strains harboring and genes had the highest frequency among all genotypes. A RAPD-PCR dendrogram divided and strains into three and six groups, respectively.
CONCLUSION
A notable rate of resistance to terbinafine in isolated dermatophytes was reported in this study. Examination of RAPD-PCR results showed that strains had higher genetic diversity than Genetic monitoring of dermatophytes must be considered an important factor in providing fungal infection prevention and treatment approaches.
PubMed: 36721519
DOI: 10.18502/ijm.v14i4.10246 -
Evidence-based Complementary and... 2020is one of the most common types of dermatophyte, causing superficial skin mycosis in human populations. Although laser treatment of onychomycosis has been proven to be...
is one of the most common types of dermatophyte, causing superficial skin mycosis in human populations. Although laser treatment of onychomycosis has been proven to be effective in the clinic, the underlying mechanism of the effect of the laser on fungal growth is not clear. The objective of the present study was to observe the ultrastructural changes of following laser irradiation and compare the transcriptome differences between the laser irradiation group and control group. In the present study, scanning electron microscopy and transmission electron microscopy were used to observe the ultrastructural changes following the laser irradiation of We also performed RNA-seq to investigate the effects of laser irradiation on by comparing the transcriptome pattern with the control. Morphological observation with electron microscopy indicated that laser irradiation resulted in the destruction of the cell membrane system. A significant induction of apoptosis was noted compared with the control group, which was confirmed by the formation of the myeloid body and protein aggregates in the cytoplasm. RNA-seq demonstrated that the expression levels of Acyl-CoA N-acyltransferase and S-adenosyl-L-methionine-dependent methyltransferase were increased in the laser irradiation group. This result indicated that laser irradiation triggered the initiation of the damage repair pathway. In conclusion, the present study suggested that laser irradiation caused physiological injury and therefore inhibited the growth of
PubMed: 32382297
DOI: 10.1155/2020/6052461