Search for antifungal compounds using a susceptible strain of Candida albicans and in vivo activity with the Galleria mellonella model

The aim of this study is to have an idea on the molecular mechanisms of C. albicans resistance to fluconazole in Burkina Faso, by studying the polymorphism of the ERG11 gene, and its implication in the C. albicans virulence and resistance in vivo according to the Galleria mellonella model; (2) Methods: Ten (10) clinical strains including, 5 resistant and 5 susceptible and 1 virulent and susceptible reference strain SC5314 are used. For the estimation of virulence, the larvae were inoculated with 10 μL of C. albicans cell suspension at variable concentrations: 2,5.105, 5.105, 1.106, and 5.106 CFU/larva of each strain. For the in vivo efficacy study, fluconazole was administered at 1, 4 and 16 mg/kg respectively to G. mellonella larvae, after infection by inoculum 5.106 CFU / larvae of each strain; (3) Results: Six (6) non-silent mutations in the ERG11 gene (K143R, F145L, G307S, S405F, G448E, V456I on ERG11p) were found in 4 resistant isolates. Larval mortality depended on fungal burden and strain. The inoculum 5.106 CFU caused 100% mortality in 2 days for the 2 CAAL-1 and CAAL-2 strains carrying the F145L mutation, in 3 days for the reference strain SC5314, in 4 days for the ensemble of resistant strains, and in 5 days for the ensemble of susceptible strains. The comparison of the mortality due to the reference strain SC5314 CFU / larva and the average mortality due to the two mutant F145L strains, shows a significant difference (P <0.05).Fluconazole significantly protected (P> 0.05) the larvae from infection by susceptible strains and the reference strain. However, 100% mortality in 6 days after injection of the resistant strains, was observed (4) Conclusions: Certain mutations in the ERG11 gene such as the F145L mutation are thought to be a source of increased virulence in Candida albicans. Fluconazole effectively protected larvae from infection by susceptible strains in vivo, unlike resistant strain

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In Vitro and In Vivo Anti-infective Potential of Thymol Against Early Childhood Caries Causing Dual Species Candida albicans and Streptococcus mutans

Frontiers in Pharmacology ◽

10.3389/fphar.2021.760768 ◽

2021 ◽

Vol 12 ◽

Author(s):

Arumugam Priya ◽

Anthonymuthu Selvaraj ◽

Dass Divya ◽

Ramalingam Karthik Raja ◽

Shunmugiah Karutha Pandian

Keyword(s):

Early Childhood ◽

Candida Albicans ◽

Streptococcus Mutans ◽

Early Childhood Caries ◽

Galleria Mellonella ◽

Biological Activities ◽

Infective Potential ◽

Childhood Caries

Early childhood caries (ECC), a severe form of caries due to cross-kingdom interaction of Candida albicans and Streptococcus mutans, is a serious childhood dental disease that affects majority of the children with poor background. The present study investigated the anti-infective potential of thymol against C. albicans and S. mutans dual species for the management of ECC. Thymol, a plant derivative of the monoterpene group, has been well known for its numerous biological activities. Thymol at 300 μg/ml concentration completely arrested growth and proliferation of dual species of C. albicans and S. mutans. Rapid killing efficacy of pathogens, within a span of 2 min, was observed in the time kill assay. In addition, at sub-inhibitory concentrations, thymol effectively diminished the biofilm formation and virulence of both C. albicans and S. mutans such as yeast-to-hyphal transition, hyphal-to-yeast transition, filamentation, and acidogenicity and acidurity, respectively, in single and dual species state. qPCR analysis was consistent with virulence assays. Also, through the invertebrate model system Galleria mellonella, in vivo toxicity and efficacy of the phytocompound was assessed, and it was found that no significant toxic effect was observed. Moreover, thymol was found to be proficient in diminishing the infection under single and dual state in in vivo condition. Overall, the results from the present study illustrate the anti-infective potential of thymol against the ECC-causing dual species, C. albicans and S. mutans, and the applicability of thymol in medicated dentifrice formulation.

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In vitro and in vivo activity of chelerythrine against Candida albicans and underlying mechanisms

Future Microbiology ◽

10.2217/fmb-2019-0178 ◽

2019 ◽

Vol 14 (18) ◽

pp. 1545-1557 ◽

Cited By ~ 4

Author(s):

Ying Gong ◽

Siwen Li ◽

Weixin Wang ◽

Yiman Li ◽

Wenli Ma ◽

...

Keyword(s):

Candida Albicans ◽

Antifungal Activity ◽

Calcium Concentration ◽

Galleria Mellonella ◽

Hyphal Growth ◽

Drug Transporter ◽

Antifungal Effect ◽

Underlying Mechanisms

Aim: To evaluate whether chelerythrine (CHT) exhibited antifungal activity against Candida albicans in vitro and in vivo and to explore the underlying mechanisms. Materials & methods: Broth microdilution assay and Galleria mellonella model were used to evaluate the antifungal effect in vitro and in vivo, respectively. Mechanism studies were investigated by morphogenesis observation, Fluo-3/AM, DCFH-DA and rhodamine6G assay, respectively. Results: CHT exhibited antifungal activity against C. albicans and preformed biofilms with minimum inhibitory concentrations ranged from 2 to 16 μg/ml. Besides, CHT protected G. mellonella larvae infected by C. albicans. Mechanisms studies revealed that CHT inhibited hyphal growth, increased intracellular calcium concentration, induced accumulation of reactive oxygen species and inhibited drug transporter activity. Conclusion: CHT exhibited antifungal activity against C. albicans.

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Minimal Inhibitory Concentration (MIC)-Phenomena in Candida albicans and Their Impact on the Diagnosis of Antifungal Resistance

Journal of Fungi ◽

10.3390/jof5030083 ◽

2019 ◽

Vol 5 (3) ◽

pp. 83 ◽

Cited By ~ 2

Author(s):

Ulrike Binder ◽

Maria Aigner ◽

Brigitte Risslegger ◽

Caroline Hörtnagl ◽

Cornelia Lass-Flörl ◽

...

Keyword(s):

Candida Albicans ◽

Treatment Response ◽

Minimal Inhibitory Concentration ◽

Antifungal Therapy ◽

Inhibitory Concentration ◽

Galleria Mellonella ◽

Antifungal Susceptibility ◽

Infection Model ◽

The Impact

Antifungal susceptibility testing (AFST) of clinical isolates is a tool in routine diagnostics to facilitate decision making on optimal antifungal therapy. The minimal inhibitory concentration (MIC)-phenomena (trailing and paradoxical effects (PXE)) observed in AFST complicate the unambiguous and reproducible determination of MICs and the impact of these phenomena on in vivo outcome are not fully understood. We aimed to link the MIC-phenomena with in vivo treatment response using the alternative infection model Galleria mellonella. We found that Candida albicans strains exhibiting PXE for caspofungin (CAS) had variable treatment outcomes in the Galleria model. In contrast, C. albicans strains showing trailing for voriconazole failed to respond in vivo. Caspofungin- and voriconazole-susceptible C. albicans strains responded to the respective antifungal therapy in vivo. In conclusion, MIC data and subsequent susceptibility interpretation of strains exhibiting PXE and/or trailing should be carried out with caution, as both effects are linked to drug adaptation and treatment response is uncertain to predict.

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Virulence of Candida albicans mutants toward larval Galleria mellonella (Insecta, Lepidoptera, Galleridae)

Canadian Journal of Microbiology ◽

10.1139/w03-064 ◽

2003 ◽

Vol 49 (8) ◽

pp. 514-524 ◽

Cited By ~ 47

Author(s):

Gary B Dunphy ◽

Ursula Oberholzer ◽

Malcolm Whiteway ◽

Robert J Zakarian ◽

Iian Boomer

Keyword(s):

Candida Albicans ◽

Galleria Mellonella ◽

Fat Body ◽

Yeast Cells ◽

Apolipophorin Iii ◽

Yeast Extract Peptone Dextrose ◽

Myosin I ◽

Yeast Phase ◽

Induced Immunity

Culture medium affected the virulence of a strain of Candida albicans toward Galleria mellonella larvae, but the yeast growth rates in yeast extract peptone dextrose broth and synthetic Galleria serum were not correlated with yeast virulence. Virulent C. albicans grew rapidly in larval serum, whereas, it limited nodulation and continued development in vivo, producing toxins that damaged the hemocytes and fat body. Nonpathogenic yeast-phase cells grew slowly in larval serum but induced extensively melanized nodules in vivo and developed no further. There was no discernible relationship in 14 exo-enzymes between the virulent and avirulent yeast strains and virulence. The avirulent myosin-I-defective yeast cells were rapidly removed from the hemolymph in vivo because of lysozyme-mediated yeast agglutination and the possible binding of the yeast cells by lysozyme and apolipophorin-III. Both lysozyme and apolipophorin-III are proteins that bind β-1,3-glucan. Finally, insects with nonpathogenic C. albicans exhibited induced immunity and were more resistant to candidiasis from the wild-type yeast cells than were noninduced insects.Key words: Candida, virulence, insect, nodule, melanization, apolipophorin-III.

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Anti-adhesive and anti-biofilm activity of NC-E08. In vitro and in vivo study using Galleria mellonella infection model

Revista dos Trabalhos de Iniciação Científica da UNICAMP ◽

10.20396/revpibic262018506 ◽

2019 ◽

Author(s):

Gabriela Fernanda Bombarda ◽

Janaina de Cássia Orlandi Sardi ◽

Pedro L. Rosalen ◽

Josy G. Lazarini ◽

Eder R. Paganini ◽

...

Keyword(s):

Candida Albicans ◽

Biofilm Formation ◽

Early Childhood Caries ◽

Galleria Mellonella ◽

Infection Model ◽

Oral Diseases ◽

Antimicrobial Drugs ◽

Structural Analogues

Biofilms are organized microbial communities formed from an ecological succession. Biofilm formation functions as a mechanism of virulence and favors the development of diseases, including oral diseases such as dental caries and periodontal disease, in which the microorganisms Streptococcus mutans and Candida albicans are closely related. Previous studies have shown that interactions between S. mutans and C. albicans are associated with the pathogenesis of early childhood caries (ECC). Therefore, there is a great interest in finding new prototypes for antimicrobial drugs, mainly for the development of structural analogues of chalcones, which constitute one of the largest classes of natural products belonging to the flavonoid family and are considered strategic molecules for this purpose.

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Zinc Oxide Nanoparticles Prime a Protective Immune Response in Galleria mellonella to Defend Against Candida albicans

Frontiers in Microbiology ◽

10.3389/fmicb.2021.766138 ◽

2021 ◽

Vol 12 ◽

Author(s):

Mei-nian Xu ◽

Li Li ◽

Wen Pan ◽

Huan-xin Zheng ◽

Meng-lei Wang ◽

...

Keyword(s):

Immune Response ◽

Zinc Oxide ◽

Candida Albicans ◽

Zinc Oxide Nanoparticles ◽

Galleria Mellonella ◽

Oxide Nanoparticles ◽

Protective Effects ◽

Zno Nps

Purpose: Zinc oxide nanoparticles (ZnO-NPs) have exerted antimicrobial properties. However, there is insufficient evaluation regarding the in vivo antifungal activity of ZnO-NPs. This study aimed to investigate the efficacy and mechanism of ZnO-NPs in controlling Candida albicans in the invertebrate Galleria mellonella.Methods:Galleria mellonella larvae were injected with different doses of ZnO-NPs to determine their in vivo toxicity. Non-toxic doses of ZnO-NPs were chosen for prophylactic injection in G. mellonella followed by C. albicans infection. Then the direct in vitro antifungal effect of ZnO-NPs against C. albicans was evaluated. In addition, the mode of action of ZnO-NPs was assessed in larvae through different assays: quantification of hemocyte density, morphology observation of hemocytes, characterization of hemocyte aggregation and phagocytosis, and measurement of hemolymph phenoloxidase (PO) activity.Results: Zinc oxide nanoparticles were non-toxic to the larvae at relatively low concentrations (≤20 mg/kg). ZnO-NP pretreatment significantly prolonged the survival of C. albicans-infected larvae and decreased the fungal dissemination and burden in the C. albicans-infected larvae. This observation was more related to the activation of host defense rather than their fungicidal capacities. Specifically, ZnO-NP treatment increased hemocyte density, promoted hemocyte aggregation, enhanced hemocyte phagocytosis, and activated PO activity in larvae.Conclusion: Prophylactic treatment with lower concentrations of ZnO-NPs protects G. mellonella from C. albicans infection. The innate immune response primed by ZnO-NPs may be part of the reason for the protective effects. This study provides new evidence of the capacity of ZnO-NPs in enhancing host immunity and predicts that ZnO-NPs will be attractive for further anti-infection applications.

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Effect of different wavelengths and dyes on Candida albicans : In vivo study using Galleria mellonella as an experimental model

Photodiagnosis and Photodynamic Therapy ◽

10.1016/j.pdpdt.2017.01.181 ◽

2017 ◽

Vol 18 ◽

pp. 34-38 ◽

Cited By ~ 9

Author(s):

Elisabetta Merigo ◽

Stefania Conti ◽

Tecla Ciociola ◽

Carlo Fornaini ◽

Luciano Polonelli ◽

...

Keyword(s):

Candida Albicans ◽

Experimental Model ◽

Galleria Mellonella ◽

In Vivo Study

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Anti-Candida albicans Activity of Thiazolylhydrazone Derivatives in Invertebrate and Murine Models

Journal of Fungi ◽

10.3390/jof4040134 ◽

2018 ◽

Vol 4 (4) ◽

pp. 134 ◽

Cited By ~ 5

Author(s):

Lana Cruz ◽

Larissa Lopes ◽

Felipe de Camargo Ribeiro ◽

Nívea de Sá ◽

Cleudiomar Lino ◽

...

Keyword(s):

Candida Albicans ◽

Antifungal Activity ◽

Galleria Mellonella ◽

Larval Survival ◽

In Vivo Model ◽

Murine Models ◽

Greater Wax Moth ◽

Fungal Load ◽

Systemic Model

Candidiasis is an opportunistic fungal infection with Candida albicans being the most frequently isolated species. Treatment of these infections is challenging due to resistance that can develop during therapy, and the limited number of available antifungal compounds. Given this situation, the aim of this study was to evaluate the antifungal activity of four thiazolylhydrazone compounds against C. albicans. Thiazolylhydrazone compounds 1, 2, 3, and 4 were found to exert antifungal activity, with MICs of 0.125–16.0 μg/mL against C. albicans. The toxicity of the compounds was evaluated using human erythrocytes and yielded LC50 > 64 μg/mL. The compounds were further evaluated using the greater wax moth Galleria mellonella as an in vivo model. The compounds prolonged larval survival when tested between 5 and 15 mg/kg, performing as well as fluconazole. Compound 2 was evaluated in murine models of oral and systemic candidiasis. In the oral model, compound 2 reduced the fungal load on the mouse tongue; and in the systemic model it reduced the fungal burden found in the kidney when tested at 10 mg/kg. These results show that thiazolylhydrazones are an antifungal towards C. albicans with in vivo efficacy.

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