scholarly journals A variant ECE1 allele contributes to reduced pathogenicity of Candida albicans during vulvovaginal candidiasis via altered secretion of candidalysin

2021 ◽  
Vol 3 (12) ◽  
Author(s):  
Junyan Liu ◽  
Emily Sansevere ◽  
Katherine Barker ◽  
Hubertine Willems ◽  
David Lowes ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Amino Acid Sequences ◽  
Vulvovaginal Candidiasis ◽  
Clinical Isolates ◽  
Disease States ◽  
Peptide Toxin ◽  
Future Work

Background: Candida albicans is the primary etiological agent of vulvovaginal candidiasis (VVC) and exerts its pathogenicity through secretion of the peptide toxin candidalysin encoded by the ECE1 gene. A highly conserved variant ECE1 sequence exists across a diverse set of clinical isolates. Thus, we sought to determine the relative pathogenicity and mechanism(s) associated with this alternative ECE1 allele. Methods: Isogenic strains harboring WT or variant ECE1 sequences were engineered in an Δ/Δece1 background. After confirmation of equivalent expression by qPCR, pathogenicity of strains were tested using in vitro epithelial cell and in vivo VVC models of infection and LDH, IL-1β, neutrophil levels monitored. Follow up studies using synthetic candidalysin peptide were also performed. Lastly, a panel of ECE1 chimeras were constructed to assess potential processing defects and detected by a novel HiBiT-tagging approach. Results: Strains transformed with either the variant full length ECE1 or candidalysin allele, as compared to the WT sequence, demonstrated significantly reduced immunopathogenicity during in vitro or in vivo infection despite equivalent fungal burden. Interestingly, epithelial challenge with WT or variant synthetic peptide revealed similar capacity to elicit damage and IL-1β. Allele profiling and ECE1 chimera experiments demonstrated that defects in pathogenicity are at least partly due to inefficient ECE1 processing at the peptide 2-peptide 3 junction. Discussion: The ECE1 gene displays conserved polymorphisms that alter candidalysin secretion and strain pathogenicity. Future work is focused on determining specific amino acid sequences that contribute to these affects across clinical isolates and disease states.

Spilanthol as a promising antifungal alkylamide for the treatment of vulvovaginal candidiasis

2021 ◽  
Author(s):  
Rodrigo L Fabri ◽  
Jhamine C O Freitas ◽  
Ari S O Lemos ◽  
Lara M Campos ◽  
Irley O M Diniz ◽  
...  
Keyword(s):  
Cell Wall ◽  
Candida Albicans ◽  
Antifungal Activity ◽  
Cell Membrane ◽  
Multidrug Resistant ◽  
Fungal Strain ◽  
Vulvovaginal Candidiasis ◽  
Biofilm Matrix

Abstract Spilanthol is a bioactive alkylamide from the native Amazon plant species, Acmella oleracea. However, antifungal activities of spilanthol and its application to the therapeutic treatment of candidiasis remains to be explored. This study sought to evaluate the in vitro and in vivo antifungal activity of spilanthol previously isolated from A. oleracea (spilanthol(AcO)) against Candida albicans ATCC® 10231™, a multidrug-resistant fungal strain. Microdilution methods were used to determine inhibitory and fungicidal concentrations of spilanthol(AcO). In planktonic cultures, the fungal growth kinetics, yeast cell metabolic activity, cell membrane permeability and cell wall integrity were investigated. The effect of spilanthol(AcO) on the proliferation and adhesion of fungal biofilms was evaluated by whole slide imaging and scanning electron microscopy. The biochemical composition of the biofilm matrix was also analyzed. In parallel, spilanthol(AcO) was tested in vivo in an experimental vulvovaginal candidiasis model. Our in vitro analyses in C. albicans planktonic cultures detected a significant inhibitory effect of spilanthol(AcO), which affects both yeast cell membrane and cell wall integrity, interfering with the fungus growth. C. albicans biofilm proliferation and adhesion, as well as, carbohydrates and DNA in biofilm matrix were reduced after spilanthol(AcO) treatment. Moreover, infected rats treated with spilanthol(AcO) showed consistent reduction of both fungal burden and inflammatory processes compared to the untreated animals. Altogether, our findings demonstrated that spilanthol(AcO) is an bioactive compound against planktonic and biofilm forms of a multidrug resistant C. albicans strain. Furthermore, spilanthol(AcO) can be potentially considered for therapeutical treatment of vulvovaginal candidiasis caused by C. albicans. Lay Abstract This study sought to evaluate the antifungal activity of spilanthol against Candida albicans ATCC® 10 231™, a multidrug-resistant fungal strain. Our findings demonstrated that spilanthol(AcO) can be potentially considered for therapeutical treatment of vulvovaginal candidiasis caused by C. albicans.

scholarly journals Antifungal activity of Ocimum gratissimum L., Lantana camara L. & Pteleopsis suberosa Engl. & Dies used in the treatment of vulvovaginal candidiasis in Benin

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Jean Robert Klotoe ◽  
Brice Armand Fanou ◽  
Eric Agbodjento ◽  
Arnaud Houehou ◽  
Lauris Fah ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Aqueous Extract ◽  
Lantana Camara ◽  
Vulvovaginal Candidiasis ◽  
Reference Drug ◽  
Clinical Strains ◽  
Ocimum Gratissimum

Abstract Background Vulvovaginal candidiasis is a widespread mycotic infection that affects a large proportion of women of childbearing age. Its management in traditional medicine is based on the use of medicinal plants. This study aimed to evaluate the antifungal activity of Ocimum gratissimum L., Lantana camara L. and Pteleopsis suberosa Engl. & Diels used in the treatment of vulvovaginal candidiasis in Benin. Results The data obtained from the in vitro antifungal test show that the strains tested (ATCC 90028 and two clinical strains: 1MA and 3MA) were more sensitive to aqueous extracts with a better effect for Pteleopsis suberosa. This potential of the tested extracts correlated with their richness in total polyphenols. The extract of the Pteleopsis suberosa was very active on the inhibition of the reference strain ATCC 90028. On the clinical strains (1MA and 3MA) the aqueous extract of Pteleopsis suberosa showed a better MIC on the 1MA strain. In vivo model, inoculation of 100 µL of the concentrated Candida albicans suspension 1.5 × 105 UFC/mL induced the candidiasis of the female Wistar rat. The treatment with the aqueous extract of Pteleopsis suberosa, like fluconazole (reference drug), significantly reduced Candida albicans infection at a dose of 100 mg/kg after 1, 7 and 13 days of treatment. Conclusion This study revealed the potential antifungal of the Ocimum gratissimum, Lantana camara and Pteleopsis suberosa. Pteleopsis suberosa has better antifungal activity in vitro and in vivo. These observations justify the use of their medicinal plant in the traditional treatment of vulvovaginal candidiasis in Benin.

scholarly journals Comparative resistance of Candida albicans clinical isolates to fluconazole and itraconazole in vitro and in vivo in a murine model.

1996 ◽  
Vol 40 (6) ◽  
pp. 1342-1345 ◽  
Author(s):  
A Valentin ◽  
R Le Guennec ◽  
E Rodriguez ◽  
J Reynes ◽  
M Mallie ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Murine Model ◽  
Survival Rates ◽  
Drug Regimen ◽  
Clinical Isolates ◽  
In Vitro Susceptibility ◽  
Microdilution Method ◽  
Broth Microdilution Method

Relationships between azole susceptibility and in vivo response to antifungal therapy in a murine model of candidiasis were investigated for Candida albicans isolates sampled from human immunodeficiency virus type 1-positive patients with oropharyngeal candidiasis. The susceptibilities of seven clinical isolates and two reference strains to fluconazole (FCZ) and itraconazole (ITZ) were determined in vitro by the broth microdilution method. Four isolates were resistant to FCZ and ITZ, two were susceptible to both azoles, and three were resistant to FCZ and susceptible to ITZ (dissociated resistance). CD1 mice were inoculated with each isolate and treated with either FCZ or ITZ (drug regimen, 5 mg/kg of body weight twice daily for 5 days). Quantitative cultures of kidneys were performed at the end of the treatment. On the other hand, the survival rates of the mice were followed daily. These two parameters were clearly correlated with in vitro susceptibility. Thus, the phenomenon of a dissociation of resistance to FCZ and ITZ may be found in vivo as well as in vitro.

scholarly journals KY-62, a Polyene Analog of Amphotericin B, for Treatment of Murine Candidiasis

1998 ◽  
Vol 42 (1) ◽  
pp. 147-150 ◽  
Author(s):  
John R. Graybill ◽  
Laura K. Najvar ◽  
Annette Fothergill ◽  
Thomas Hardin ◽  
Michael Rinaldi ◽  
...  
Keyword(s):  
Body Weight ◽  
Candida Albicans ◽  
Amphotericin B ◽  
Clinical Development ◽  
Water Soluble ◽  
Clinical Isolates ◽  
In Vitro Testing ◽  
Immunocompetent Mice

ABSTRACT KY-62 is a water-soluble analog of amphotericin B. In vitro testing of five clinical isolates of Candida albicans showed KY-62 to have potency similar to that of amphotericin B. KY-62 was administered to mice infected intravenously with C. albicans. In vivo, KY-62 was effective in immunocompetent mice, with potency similar to that of amphotericin B. KY-62 was well tolerated up to 30 mg/kg of body weight per dose, an amount that would be lethal with amphotericin B. KY-62 was less effective in mice rendered neutropenic with 5-fluorouracil. The addition of flucytosine had little effect. KY-62 may have potential for clinical development.

scholarly journals Assessment of the Paradoxical Effect of Caspofungin in Therapy of Candidiasis

2006 ◽  
Vol 50 (4) ◽  
pp. 1293-1297 ◽  
Author(s):  
Karl V. Clemons ◽  
Marife Espiritu ◽  
Rachana Parmar ◽  
David A. Stevens
Keyword(s):  
Candida Albicans ◽  
Clinical Isolates ◽  
Paradoxical Effect ◽  
Cure Rate ◽  
Systemic Model ◽  
Paradoxical Growth ◽  
Intravenous Inoculation

ABSTRACT Paradoxical growth of some Candida albicans isolates in the presence of caspofungin (CAS) in vitro has been demonstrated previously. We sought to determine whether a similar phenomenon occurred in vivo. A systemic model of candidiasis was studied in CD-1 mice by intravenous inoculation of different isolates of C. albicans. Infected animals were treated with CAS at various dosages (0.01 to 20 mg/kg) and CFU remaining in the kidneys determined. Four clinical isolates that showed paradoxical growth in vitro and one that did not were tested. Recovery of CFU from the kidneys showed that dosages of CAS at 0.1 mg/kg and above were efficacious in the reduction of C. albicans, but were not curative. Against isolates that show paradoxical growth in vitro, CAS was efficacious, but lacked dose responsiveness above 0.5 mg/kg against three of the four. One isolate, 95-68, showed paradoxical growth in vivo with significantly higher CFU recovered from mice given CAS at 20 mg/kg than those given CAS at 5 mg/kg, but the effect was not reproducible in a subsequent experiment. When CAS was given prophylactically and therapeutically, improved efficacy and cure rate were observed. Overall, these data indicate that CAS is highly efficacious against systemic murine candidiasis and a paradoxical effect was not reproducibly demonstrated in vivo.

scholarly journals Azole Antifungal Resistance in Candida albicans and Candida glabrata Isolated from Vulvovaginal Candidiasis Patients

2021 ◽  
Vol 16 (2) ◽  
Author(s):  
Niloofar Deravi ◽  
Mobina Fathi ◽  
Seyede Nadia Tabatabaeifar ◽  
Parichehr Pooransari ◽  
Bahram Ahmadi ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Candida Glabrata ◽  
Antifungal Susceptibility ◽  
Vulvovaginal Candidiasis ◽  
Clinical Isolates ◽  
In Vitro Activity ◽  
Normal Women ◽  
In Vitro Antifungal Susceptibility ◽  
Iranian Patients

Background: Vulvovaginal candidiasis (VVC) is the most frequent fungal disorder in healthy and normal women. Objectives: The aim of this study was to evaluate the in vitro antifungal susceptibility of clinical isolates Candida albicans and Candida glabrata, the two most common candida species in Iranian patients with VVC. Methods: One hundred and eight clinical isolates of candida, including; C. albicans (n = 77) and C. glabrata: (n = 31) were isolated from the 108 patients with VVC. The in vitro activity of caspofungin (CAS), amphotericin B (AMB), voriconazole (VRC), itraconazole (ITC), fluconazole (FLC), and nystatin (NYS) were determined according to the CLSI M27-A3 and CLSI M27-S4. Results: Our results were shown 8 (25.8 %) and 6 (7.8 %) C. glabrata and C. albicans isolates resistance to FLU, respectively. Furthermore, resistance to VRC and ITC were observed in 8.4%, and 3.7% of all isolates, and six isolates (5.6%) had intermediate MIC to CAS. Conclusions: We reported 8 (25.8 %) and 6 (7.8 %) C. glabrata and C. albicans isolates resistance to FLU, respectively. Furthermore, resistance to VRC and ITC were observed in 8.4% and 3.7% of all isolates, respectively.

scholarly journals Quercetin Assists Fluconazole to Inhibit Biofilm Formations of Fluconazole-Resistant Candida Albicans in In Vitro and In Vivo Antifungal Managements of Vulvovaginal Candidiasis

2016 ◽  
Vol 40 (3-4) ◽  
pp. 727-742 ◽  
Author(s):  
Mei Gao ◽  
Hui Wang ◽  
LiJuan Zhu
Keyword(s):  
Candida Albicans ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Vulvovaginal Candidiasis ◽  
Vaginal Mucosa ◽  
Fluconazole Resistant ◽  
Dietary Flavonoid ◽  
Fungal Adherence

Background: Vulvovaginal candidiasis (VVC) is a common gynecological disease. Candida albicans is believed to be mainly implicated in VVC occurrence, the biofilm of which is one of the virulence factors responsible for resistance to traditional antifungal agents especially to fluconazole (FCZ). Quercetin (QCT) is a dietary flavonoid and has been demonstrated to be antifungal against C. albicans biofilm. Methods: 17 C. albicans isolates including 15 clinical ones isolated from VVC patients were employed to investigate the effects of QCT and/or FCZ on the inhibition of C. albicans biofilm. Results: We observed that 64 µg/mL QCT and/or 128 µg/mL FCZ could (i) be synergistic against 10 FCZ-resistant planktonic and 17 biofilm cells of C. albicans, (ii) inhibit fungal adherence, cell surface hydrophobicity (CSH), flocculation, yeast-to-hypha transition, metabolism, thickness and dispersion of biofilms; (iii) down-regulate the expressions of ALS1, ALS3, HWP1, SUN41, UME6 and ECE1 and up-regulate the expressions of PDE2, NRG1 and HSP90, and we also found that (iv) the fungal burden was reduced in vaginal mucosa and the symptoms were alleviated in a murine VVC model after the treatments of 5 mg/kg QCT and/or 20 mg/kg FCZ. Conclusion: Together with these results, it could be demonstrated that QCT could be a favorable antifungal agent and a promising synergist with FCZ in the clinical management of VVC caused by C. albicans biofilm.

scholarly journals A variant ECE1 allele contributes to reduced pathogenicity of Candida albicans during vulvovaginal candidiasis

2021 ◽  
Vol 17 (9) ◽  
pp. e1009884 ◽  
Author(s):  
Junyan Liu ◽  
Hubertine M. E. Willems ◽  
Emily A. Sansevere ◽  
Stefanie Allert ◽  
Katherine S. Barker ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Vulvovaginal Candidiasis ◽  
Clinical Isolates ◽  
Vaginal Mucosa ◽  
Reading Frame ◽  
Human Fungal Pathogen ◽  
Vaginal Epithelial Cells ◽  
Life Issues

Vulvovaginal candidiasis (VVC), caused primarily by the human fungal pathogen Candida albicans, results in significant quality-of-life issues for women worldwide. Candidalysin, a toxin derived from a polypeptide (Ece1p) encoded by the ECE1 gene, plays a crucial role in driving immunopathology at the vaginal mucosa. This study aimed to determine if expression and/or processing of Ece1p differs across C. albicans isolates and whether this partly underlies differential pathogenicity observed clinically. Using a targeted sequencing approach, we determined that isolate 529L harbors a similarly expressed, yet distinct Ece1p isoform variant that encodes for a predicted functional candidalysin; this isoform was conserved amongst a collection of clinical isolates. Expression of the ECE1 open reading frame (ORF) from 529L in an SC5314-derived ece1Δ/Δ strain resulted in significantly reduced vaginopathogenicity as compared to an isogenic control expressing a wild-type (WT) ECE1 allele. However, in vitro challenge of vaginal epithelial cells with synthetic candidalysin demonstrated similar toxigenic activity amongst SC5314 and 529L isoforms. Creation of an isogenic panel of chimeric strains harboring swapped Ece1p peptides or HiBiT tags revealed reduced secretion with the ORF from 529L that was associated with reduced virulence. A genetic survey of 78 clinical isolates demonstrated a conserved pattern between Ece1p P2 and P3 sequences, suggesting that substrate specificity around Kex2p-mediated KR cleavage sites involved in protein processing may contribute to differential pathogenicity amongst clinical isolates. Therefore, we present a new mechanism for attenuation of C. albicans virulence at the ECE1 locus.

scholarly journals Beyond just hemoglobin: Red blood cell potentiation of hemoglobin-oxygen unloading in fish

2017 ◽  
Vol 123 (4) ◽  
pp. 935-941 ◽  
Author(s):  
Colin J. Brauner ◽  
Till S. Harter
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Ph Regulation ◽  
In Vivo Studies ◽  
Heterogeneous Distribution ◽  
Disease States ◽  
Future Work ◽  
Improve Treatment Efficacy

Teleosts comprise 95% of fish species, almost one-half of all vertebrate species, and represent one of the most successful adaptive radiation events among vertebrates. This is thought to be in part because of their unique oxygen (O2) transport system. In salmonids, recent in vitro and in vivo studies indicate that hemoglobin-oxygen (Hb-O2) unloading to tissues may be doubled or even tripled under some conditions without changes in perfusion. This is accomplished through the short circuiting of red blood cell (RBC) pH regulation, resulting in a large arterial-venous pH difference within the RBC and induced reduction in Hb-O2 affinity. This system has three prerequisites: 1) highly pH-sensitive hemoglobin, 2) rapid RBC pH regulation, and 3) a heterogeneous distribution of plasma-accessible CA in the cardiovascular system (presence in the tissues and absence at the gills). Although data are limited, these attributes may be general characteristics of teleosts. Although this system is not likely operational to the same degree in other vertebrates, some of these prerequisites do exist, and the generation and elimination of pH disequilibrium states at the RBC will likely enhance Hb-O2 unloading to some degree. In human disease states, there are conditions that may partly satisfy those for enhanced Hb-O2 unloading, tentatively an avenue for future work that may improve treatment efficacy.

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