Combination Of Fluconazole Research Articles

Expression of Lanosterol 14-Demethylase (ERG11) Gene of Three-Drug Combinations in Candida albicans

Patients with impaired immunity are at particular risk of infections with Candida albicans. Antifungal drugs such as azoles commonly used for candidiasis treatment, but drug resistance is one of the most common problems for public health. The aim of this study was to evaluate the expression of lanosterol 14-demethylase (ERG11) gene for three-drug combinations in C. albicans. Disk diffusion and broth microdilution susceptibility tests were employed to evaluate the synergic effects of amphotericin B, fluconazole, voriconazole, ketoconazole and itraconazole. Quantification of ERG11 gene expression was carried out in C. albicans treated with three-drug combinations of fluconazole/ ketoconazole/ voriconazole and fluconazole/ ketoconazole/ itraconazole. Three-drug combinations revealed synergistic and partial synergistic effect for all tested isolates (FIC index range of 0.27-0.77). The expression levels of ERG11 were down-regulated by three-drug combination of fluconazole/ ketoconazole/ voriconazole treatment. Fluconazole synergizes with ketoconazole and voriconazole in three-drug combination against C. albicans by targeting of the ERG11 gene.

Synergistic Interaction of Fluconazole/Amphotericin B on Inhibition of Enzymes Contributes to the Pathogenesis of Candida Tropicalis

Background: Candidiasis has gained much attention in recent decades due to its increasing prevalence in immunocompromised patients. Usually, antifungals such as fluconazole and amphotricin B are used for treatment of candidiasis, but one of the major clinical problems is the emergence of antifungal resistance. Combination antifungal therapy is one of the most commonly used methods to alleviate the problem of antifungal resistance. Methods: The effect of fluconazole alone and in combination with amphotericin B on C. tropicalis isolates were performed using the Clinical and Laboratory Standards Institute (CLSI) reference method. Eventually hypha formation, time kill study, proteinase and phospholipase activity and expression of PLB and SAP2 genes were carried out to investigate the enzymes inhibitory properties of antifungal tested against C. tropicalis. Results: Results showed the significant synergic effect of fluconazole in combination with amphotericin B in inhibiting the growth of C. tropicalis isolates, with fractional inhibitory concentration indices ranging from 0.06 to 0.5. The combination of fluconazole with amphotericin B reduced the number of yeast form and inhibited the yeast to hyphae transition in C. tropicalis. The antifungals tested were able to show the effect of down regulating expression of the selected genes significantly in fluconazole/amphotericin B ranging from 1.42- to 2.27-fold. Conclusion: Our results demonstrated that the synergistic interaction of fluconazole/amphotericin B would be worth exploring for the management of candidiasis. In addition, PLB and SAP2 genes could be probable molecular targets in the synergistic interaction of fluconazole/amphotericin B in C. tropicalis.

Effect of seasonality on chemical profile and antifungal activity of essential oil isolated from leaves Psidium salutare (Kunth) O. Berg.

Medicinal plants play a crucial role in the search for components that are capable of neutralizing the multiple mechanisms of fungal resistance. Psidium salutare (Kunth) O. Berg is a plant native to Brazil used as both food and traditional medicine to treat diseases and symptoms such as stomach ache and diarrhea, whose symptoms could be related to fungal infections from the genus Candida. The objective of this study was to investigate the influence of seasonal variability on the chemical composition of the Psidium salutare essential oil, its antifungal potential and its effect on the Candida albicans morphogenesis. The essential oils were collected in three different seasonal collection periods and isolated by the hydrodistillation process in a modified Clevenger apparatus with identification of the chemical composition determined by gas chromatography coupled to mass spectrometry (GC/MS). The antifungal assays were performed against Candida strains through the broth microdilution method to determine the minimum fungicidal concentration (MFC). Fungal growth was assessed by optical density reading and the Candida albicans dimorphic effect was evaluated by optical microscopy in microculture chambers. The chemical profile of the essential oils identified 40 substances in the different collection periods with γ-terpinene being the predominant constituent. The antifungal activity revealed an action against the C. albicans, C. krusei and C. tropicalis strains with an IC50 ranging from 345.5 to 2,754.2 µg/mL and a MFC higher than 1,024 µg/mL. When combined with essential oils at sub-inhibitory concentrations (MIC/16), fluconazole had its potentiated effect, i.e. a synergistic effect was observed in the combination of fluconazole with P.salutare oil against all Candida strains; however, for C. albicans, its effect was reinforced by the natural product in all the collection periods. The results show that the Psidium salutare oil affected the dimorphic transition capacity, significantly reducing the formation of hyphae and pseudohyphae in increasing concentrations. The results show that P. salutare oil exhibits a significant antifungal activity against three Candida species and that it can act in synergy with fluconazole. These results support the notion that this plant may have a potential use in pharmaceutical and preservative products.

Corticosteroids in the Management of Severe Coccidioidomycosis

BackgroundThere is limited data suggesting that recovery from severe pulmonary infection with Coccidioides may be hastened by the addition of systemic corticosteroids. MethodsWe present a case report of 2 patients with persistent and progressive coccidioidomycosis who demonstrated a dramatic response to adjunctive corticosteroid therapy. ResultsBoth patients had Coccidioides immitis cultured from respiratory samples. One was a 69-year-old man who had been treated with combination fluconazole and liposomal amphotericin for over 6 weeks, with persistent fever and pneumonia. The other was a 61-year-old man treated with fluconazole and then amphotericin for 3 weeks, with progression to acute respiratory distress syndrome and shock. Both received short courses of intravenous methylprednisolone and recovered to be discharged home. ConclusionsAs opposed to associated hypersensitivity, corticosteroid treatment in these cases was directed at modulating the ongoing destructive effects of unchecked inflammation. Rapid improvement was noted in both cases and raises the possibility that the addition of systemic corticosteroids may hasten recovery in patients with severe coccidioidomycosis.

Antimicrobial and toxicity profiles evaluation of the Chamomile (Matricaria recutita L.) essential oil combination with standard antimicrobial agents

In this present study, commercial Pharmacopeia (PhEur) grade chamomile essential oil (Matricariae aetheroleum) was combined with different antimicrobial agents including ampicillin sodium, cefuroxime acetyl, tetracycline hydrochloride, fluconazole and nystatin. All combinations were evaluated in vitro against pathogenic standard and clinical resistant Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacterial isolates as well as against Candida albicans for their broad antimicrobial effectiveness. Furthermore, the essential oil was fractioned by column chromatography using n-hexane, diethyl ether, dichloromethane and methanol, respectively. Additionally, all fractions of essential oil were tested in combinations for their minimum inhibitory concentrations (MIC) as well as for their fractional inhibitory concentrations (FIC) against the resistant microbial pathogens. Antimicrobial activities were evaluated by microdilution method and antimicrobial interactions were assayed using the checkerboard method. Cytotoxicity of compounds were evaluated using Cytotox-XTT-1 Parameter Kit in WS1 cells and Aliivibrio fischeri bioluminescence toxicity assay. The analyses proved that α-bisabolol oxide A (47.7%), (E)-β-farnesene (21.5%), α-bisabolol oxide B (6.2%), α-bisabolone oxide A (5.8%), chamazulene (4.1%) and α-bisabolol (2.2%), respectively were the major compounds and in compliance with PhEur. The essential oil combination of fluconazole and nystatin showed “synergic and additive inhibitory effects” against the clinical Candida strain. According to the IC50 values obtained, the inhibitory concentrations of combinations against the clinical Candida strain can be considered to be selective when compared with its effect on WS1 cells. Additionally, the essential oil combination of fluconazole and nystatin showed low toxicity against A. fischeri.

Anticandidal synergistic activity of Ocimum sanctum and fluconazole of azole resistance strains of clinical isolates

Candida albicans is the most prevalent fungal pathogen in humans. It is the causative agent and most associated with serious fungal infection, accounting for more than 90% of cases. It is a most common cause of deep mycoses and vulvovaginal candidiasis. In the present study we found that methanolic extract of O. sanctum in combination of fluconazole shows higher zone of inhibition and lesser MIC values as compared to methanolic extract of leaves of O. sanctum or fluconazole when used alone. Synergistic antimicrobial activity was found when methanolic extract of leaves of O. sanctum was used in combination with fluconazole against C. albicans azole resistance strains isolated from catheter tip (CT) and high vaginal swab (HVS) (FIC≤0.5). Partial synergistic activity was observed against urine (U). Methanolic extract of stem of O. sanctum in combination with fluconazole gave indifferent antifungal results (FIC=1.0–4.0). Benzene extract of the leaf and stem of O. sanctum in combination with fluconazole showed indifferent antifungal results (FIC=1.0–4.0). Aqueous extract of leaves of O. sanctum in combination with fluconazole showed partial synergistic antimicrobial activity against catheter tip (CT) and high vaginal swab (HVS) and urine (U) (FIC=0.5–1.0). In the present study we evaluate the synergism of C. albicans against azole resistant clinical isolates. This study indicates clear evidence supporting the traditional use of O. sanctum in treating Candida infectious diseases.

In vitro synergy with fluconazole plus doxycycline or tigecycline against clinical Candida glabrata isolates.

Candida species, traditionally viewed as opportunistic agents, are increasingly seen as a cause of infection in hospitalized patients. Treatment options are limited to a few classes of drugs. Increased resistance, especially by Candida glabrata, is problematic. We investigated the interaction between fluconazole and doxycycline or tigecycline, using clinically unique blood culture C. glabrata isolates. Eighteen isolates were screened using an Etest® MIC:MIC synergy method. With the doxycycline plus fluconazole combination, 28% of isolates showed synergy; tigecycline plus fluconazole showed 94% synergy. No antagonism was seen. The mechanisms of these interactions are unclear. Further research is warranted to assess clinical utility.

Caffeic acid phenethyl ester synergistically enhances the antifungal activity of fluconazole against resistant Candida albicans

BackgroundOwing to the increased morbidity and mortality associated with invasive fungal infections, treatments with a combination of antifungal agents are often considered. Caffeic acid phenethyl ester (CAPE), a major active component of propolis, possesses many biological activities, including antibacterial, antiviral, antioxidant, anti-inflammatory, and anticancer effects. PurposeThis study aimed to evaluate the interaction between CAPE and fluconazole (FLC) against Candida albicans. MethodsMicrodilution checkerboard and time-kill assays were employed to evaluate the in vitro interaction between CAPE and FLC. The data obtained from the checkerboard tests were analyzed by the fractional inhibitory concentration index (FICI).The antifungal activity of the CAPE and FLC combination was evaluated in vivo in a Caenorhabditis elegans model of infection. ResultsWe observed that when used in combination, CAPE acted synergistically with FLC against FLC-resistant clinical isolates of C. albicans. In addition, the CAPE-FLC combination significantly extended the longevity and reduced fungal burden in C. elegans when compared with treatment with FLC or CAPE alone. ConclusionThese results indicate that the use of CAPE and FLC in combination has considerable therapeutic potential against resistant C. albicans.

The Role of Curcumin in Inhibiting Growth of Oropharyngeal Isolates of Candida albicans Fluconazole-Resistant Strain from HIV Patients through Decreased Cdr1p Expression

Curcumin is an agent affecting epigenetic factors and the expression of drug efflux transporters such as Cdr1p. Drug efflux transporters are also affected by the epigenetic factor HAT (Histone Acetyl Transferase). HAT-Rtt109 is specific to the fungal kingdom and related to resistance to antifungal agents. Strains of the pathogenic yeast Candida albicans were isolated from AIDS patients with oropharyngeal candidiasis and assigned to control and treatment groups (fluconazole, curcumin and the combination of fluconazole + curcumin). The minimum inhibitory concentration (MIC) for C. albicans resistant strains were determined using tube dilution test in accordance with CLSI micro dilution method, followed by SDS-PAGE. Yeast DNA isolation was performed using DNA isolation kit followed by bisulfate treatment, PCR, and sequencing of Rtt109. The most significant decrease in C. albicans growth occurred on growth media treated with the combination of fluconazole and curcumin. The MIC of the combination group was lower compared to the fluconazole-only or curcuminonly groups. Protein analysis showed that Cdr1p expression for the curcumin and combination groups was decreased compared to the control and fluconazole groups. There was a similar expression of HAT-Rtt109 among four groups. Based on the alignment of Rtt109 sequences, it shows that there was similar methylation among the four groups. The synergy of curcumin and fluconazole to helped in fluconazole resistance was likely through inhibition of Cdr1p expression, but not HAT-Rtt109 or Rtt109 methylation.

Alkylated Piperazines and Piperazine-Azole Hybrids as Antifungal Agents.

The extensive use of fluconazole (FLC) and other azole drugs has caused the emergence and rise of azole-resistant fungi. The fungistatic nature of FLC in combination with toxicity concerns have resulted in an increased demand for new azole antifungal agents. Herein, we report the synthesis and antifungal activity of novel alkylated piperazines and alkylated piperazine-azole hybrids, their time-kill studies, their hemolytic activity against murine erythrocytes, as well as their cytotoxicity against mammalian cells. Many of these molecules exhibited broad-spectrum activity against all tested fungal strains, with excellent minimum inhibitory concentration (MIC) values against non-albicans Candida and Aspergillus strains. The most promising compounds were found to be less hemolytic than the FDA-approved antifungal agent voriconazole (VOR). Finally, we demonstrate that the synthetic alkylated piperazine-azole hybrids do not function by fungal membrane disruption, but instead by disruption of the ergosterol biosynthetic pathway via inhibition of the 14α-demethylase enzyme present in fungal cells.

QTc prolongation during ciprofloxacin and fluconazole combination therapy: prevalence and associated risk factors.

Ciprofloxacin and fluconazole combination therapy is frequently used as prophylaxis for, and treatment of, infections in patients with haematological malignancies. However, both drugs are known to prolong the heart rate-corrected QT (QTc) interval, which is a serious risk factor for torsade de pointes (TdP). Therefore, the aim of the current study was to assess the prevalence of QTc prolongation during ciprofloxacin and fluconazole use. The secondary objective was to determine associated risk factors of QTc prolongation in these patients. A prospective observational study was performed in patients admitted to the Erasmus University Medical Centre and treated with ciprofloxacin and fluconazole. A 12-lead electrocardiogram (ECG) was recorded at the estimated time to peak concentration (Tmax ) for the last added drug. The main outcome was the proportion of patients with QTc prolongation during treatment. Data on the following potential risk factors were collected: patient characteristics, serum electrolyte levels, dosage of ciprofloxacin and fluconazole, renal and liver function and concomitant use of other QTc-prolonging drugs and cytochrome P450 3A4 inhibitors. A total of 170 patients were included, of whom 149 (87.6%) were treated for haematological malignancies. The prevalence of QTc prolongation was 4.7%. No risk factors were found to be associated with QTc prolongation. The QTc interval increased by 10.7ms [95% confidence interval (CI) 7.2, 14.1ms] during ciprofloxacin and fluconazole combination therapy. The prevalence of QTc prolongation in patients using ciprofloxacin and fluconazole is low compared with the prevalence in the general population, which varies from 5% to 11%. In addition, no risk factors were found. Given the low prevalence, routine ECG monitoring in patients on this therapy should be reconsidered.

Renal Impairment Related to Different Antifungal Medications in Cases of Invasive Candida Infections in Tawam Hospital Pediatric Population between 2008-2015

Background: As a tertiary hospital, Tawam Hospital has been dealing with more and more complex pediatric cases. Such cases are often at higher risk of developing Invasive Candida Infections (ICI). Amphotericin B preparations continued to provide the widest coverage for all Candida strains and have been the drug of choice for definitive and empirical therapy in our institute. However, renal complications have always been a concern with this group of antifungals. Numerous studies have reported contradicting results in terms of which Amphotericin B preparation has less renal side effects. Therefore, we are here to report our own experience.Methods:We performed a retrospective cohort study of all children (15 years and younger) with ICI who were treated at Tawam Hospital from 2008 to 2015. Results:Out of the 40 patients included in this study, 7 patients were treated with Amphotericin B Liposomal (ABL). Two of them had elevated Urea/Creatinine after initiating the therapy. 11 patients were treated with Amphotericin B Lipid Complex (ABLC). Two of them had elevated Urea/Creatinine after initiating the therapy. Fluconazole was used in 14 patients. 2 of them had high Urea/Creatinine before therapy which did not show any further deterioration while on therapy. Two patients were treated with a combination of Fluconazoleand LAB. They both had high Urea/Creatinine before and after therapy. However, one of them was known to have renal failure. While 4 cases were treated with the combination of Fluconazole and ABLCamong whom one patient had high Urea/Creatinine before therapy that went down while on therapy. Conclusions:Although Amphotericin B is known to be associated with renal side effects, the newer preparations seem to offer a much safer alternative. Among the two available preparations, ABLCseemed to be safer in our experience. Fluconazole continued to have minimal renal side effects. However, just like most of the published studies on this topic, our study was limited by the small number of patients included and the retrospective nature of the study.Keywords: Invasive candida infections, Renal impairment, Amphotericin B Lipid Complex, Amphotericin B Liposomal Fluconazole.Abbreviations:ICI: Invasive Candida Infections, Amphotericin B Lipid Complex (ABLC), Amphotericin B Liposomal (ABL), CSF: cerebrospinal fluid, CLEAR: Collaborative Exchange of Antifungal Research,

Synergistic Antifungal Effect of Fluconazole Combined with Licofelone against Resistant Candida albicans.

Candida albicans (C. albicans) is one of the important opportunistic fungal pathogens that is closely associated with disseminated or chronic infections. The objective of this study is to evaluate the synergistic antifungal effect of licofelone, which is dual microsomal prostaglandin E2 synthase/lipoxygenase (mPGES-1/LOX) inhibitor in combination with fluconazole against C. albicans. Here our results showed that licofelone (16 μg/mL) can synergistically work with fluconazole (1 μg/mL) against planktonic cells of fluconazole-resistant C. albicans. The two-drug combination inhibited the C. albicans biofilm formation over 12 h, and reduced the expression of extracellular phospholipase genes, biofilm-specific genes and RAS/cAMP/PKA pathway related genes. In addition, the two-drug combination inhibited the transition from yeast to hyphal growth form, and decreased the secreted aspartyl proteinase activity, while not affecting the drug efflux pumps activity. Galleria mellonella model was also used to confirm the antifungal activity of the drug combination in vivo. This study first indicates that the combination of fluconazole and licofelone has synergistic effect against resistant C. albicans and could be a promising therapeutic strategy for the antifungal treatment.

Effect of Addition of Antifungal Agents on Physical and Biological Properties of a Tissue Conditioner: An In-Vitro Study

Purpose: Tissue conditioners are used for healing of abused oral tissues. They may harbour microorganisms causing oral diseases such as candidiasis compromising the health of the patient. Also, addition of antifungal agents into tissue conditioner may alter its properties. This study compares the anti-fungal property and mechanical properties of tissue conditioner containing different antifungal agents.Methods: Three antifungal agents, one synthetic – fluconazole, and two natural - oregano oil and virgin coconut oil were added into the tissue conditioner (Viscogel) in different concentrations. The antifungal property, tensile bond strength and viscoelasticity of Viscogel containing these antifungal agents were assessed after 24 hours, three days and seven days.Results: While, the highest antifungal activity was shown by Viscogel containing fluconazole, the maximum tensile bond strength was found to be of Viscogel alone (control). Although Viscogel alone and in combination of fluconazole showed deterioration in viscoelasticity, Viscogel in combination of natural agents showed no significant changes over the period of seven days.Conclusion: Incorporation of the natural agents in the tissue conditioner can be used as an effective alternative to systemic or topical synthetic antifungal agents.

Fucofuroeckol-A from edible marine alga Eisenia bicyclis to restore antifungal activity of fluconazole against fluconazole-resistant Candida albicans

Phlorotannins from the brown alga, Eisenia bicyclis, are known to possess strong antimicrobial activity against several microbial pathogens. In this study, the antifungal activity of phlorotannins against Candida albicans was evaluated. Among the six phlorotannins tested in the present study, fucofuroeckol-A (FF) exhibited potent antifungal activity with minimum inhibitory concentration (MIC) value of 512 μg mL−1 against C. albicans strains. It is also observed that FF restored the antifungal effect of fluconazole against fluconazole-resistant C. albicans in the combination mode. The MIC values of fluconazole against C. albicans strains drastically decreased by three- to fourfold in the combination of FF-fluconazole. Furthermore, analysis of fractional inhibitory concentration (FIC) indices revealed that the median ΣFIC against C. albicans strains ranged from 0.287 to 0.508 with FF-A and fluconazole combination indicating synergistic antifungal effects with restoring antifungal activity of fluconazole. The results obtained in this study imply that phlorotannins especially FF derived from E. bicyclis can be a potential source to develop an antifungal agent against drug-resistant C. albicans infection.

High-dose fluconazole in combination with amphotericin B is more efficient than monotherapy in murine model of cryptococcosis

Cryptococcus spp., the causative agents of cryptococcosis, are responsible for deaths of hundreds of thousands of people every year worldwide. The drawbacks of available therapeutic options are aggravated by the increased resistance of yeast to the drugs, resulting in inefficient therapy. Also, the antifungal 5FC is not available in many countries. Therefore, a combination of antifungal drugs may be an interesting option, but in vitro and theoretical data point to the possible antagonism between the main antifungals used to treat cryptococcosis, i.e., fluconazole (FLC), and amphotericin B (AMB). Therefore, in vivo studies are necessary to test the above hypothesis. In this study, the efficacy of FLC and AMB at controlling C. gattii infection was evaluated in a murine model of cryptococcosis caused by C. gattii. The infected mice were treated with FLC + AMB combinations and showed a significant improvement in survival as well as reduced morbidity, reduced lung fungal burden, and the absence of yeast in the brain when FLC was used at higher doses, according to the Tukey test and principal component analysis. Altogether, these results indicate that combinatorial optimization of antifungal therapy can be an option for effective control of cryptococcosis.

Antifungal activity and cytotoxicity of extracts and triterpenoid saponins obtained from the aerial parts of Anagallis arvensis L.

Ethnopharmacological relevanceAnagallis arvensis L. (Primulaceae) is used in argentinean northwestern traditional medicine to treat fungal infections. We are reporting the isolation and identification of compounds with antifungal activity against human pathogenic yeast Candida albicans, and toxicity evaluation. Aim of the studyto study the antifungal activity of extracts and purified compounds obtained form A. arvensis aerial parts, alone and in combinations with fluconazole (FLU), and to study the toxicity of the active compounds. Materials and methodsDisk diffusion assays were used to perform an activity-guided isolation of antifungal compounds from the aerial parts of A. arvensis. Broth dilution checkerboard and viable cell count assays were employed to determine the effects of samples and combinations of FLU + samples against Candida albicans. The chemical structures of active compounds were elucidated by spectroscopic analysis. Genotoxic and haemolytic effects of the isolated compounds were determined. ResultsFour triterpenoid saponins (1–4) were identified. Anagallisin C (AnC), exerted the highest inhibitory activity among the assayed compounds against C. albicans reference strain (ATCC 10231), with MIC-0 =1µg/mL. The Fractional Inhibitory Concentration Index (FICI=0.129) indicated a synergistic effect between AnC (0.125µg/mL) and FLU (0.031µg/mL) against C. albicans ATCC 10231. AnC inhibited C. albicans 12–99 FLU resistant strain (MIC-0 =1µg/mL), and the FICI=0.188 indicated a synergistic effect between AnC (0.125µg/mL) and fluconazole (16µg/mL). The combination AnC+ FLU exerted fungicidal activity against both C. albicans strains. AnC exerted inhibitory activity against C. albicans ATCC 10231 sessile cells (MIC50=0.5µg/mL and MIC80=1µg/mL) and against C. albicans 12–99 sessile cells (MIC50=0.75µg/mL and MIC80=1.25µg/mL). AnC exerted haemolytic effect against human red blood cells at 15µg/mL and did not exerted genotoxic effect on Bacillus subtilis rec strains. ConclusionsThe antifungal activity and lack of genotoxic effects of AnC give support to the traditional use of A. arvensis as antifungal and makes AnC a compound of interest to expand the available antifungal drugs.

Synergistic Effects and Mechanisms of Budesonide in Combination with Fluconazole against Resistant Candida albicans.

Candida albicans is an important opportunistic pathogen, causing both superficial mucosal infections and life-threatening systemic diseases in the clinic. The emergence of drug resistance in Candida albicans has become a noteworthy phenomenon due to the extensive use of antifungal agents and the development of biofilms. This study showed that budesonide potentiates the antifungal effect of fluconazole against fluconazole-resistant Candida albicans strains both in vitro and in vivo. In addition, our results demonstrated, for the first time, that the combination of fluconazole and budesonide can reverse the resistance of Candida albicans by inhibiting the function of drug transporters, reducing the formation of biofilms, promoting apoptosis and inhibiting the activity of extracellular phospholipases. This is the first study implicating the effects and mechanisms of budesonide against Candida albicans alone or in combination with fluconazole, which may ultimately lead to the identification of new potential antifungal targets.

The in vitro and in vivo efficacy of fluconazole in combination with farnesol against Candida albicans isolates using a murine vulvovaginitis model.

Farnesol is a quorum-sensing molecule that inhibits biofilm formation in Candida albicans. Previous in vitro data suggest that, in combination with certain antifungals, farnesol may have an adjuvant anti-biofilm agent. However, the in vivo efficacy of farnesol is very questionable. Therefore, the in vitro and in vivo activity of fluconazole combined with farnesol was evaluated against C. albicans biofilms using fractional inhibitory concentration index (FICI) determination, time-kill experiments and a murine vulvovaginitis model. The median biofilm MICs of fluconazole-sensitive C. albicans isolates ranged between 4 -> 512 mg/L and 150-300 μM for fluconazole and farnesol, respectively. These values were 512 -> 512 mg/L and > 300 μM for fluconazole-resistant clinical isolates. Farnesol decreased the median MICs of fluconazole by 2-64-fold for biofilms. Based on FICI, synergistic interaction was observed only in the case of the sessile SC5314 reference strain (FICIs: 0.16-0.27). In time-kill studies, only the 512 mg/L fluconazole and 512 mg/L fluconazole + 75 μM farnesol reduced biofilm mass significantly at each time point in the case of all isolates. The combination reduced the metabolic activity of biofilms for all isolates in a concentration- and time-dependent manner. Our findings revealed that farnesol alone was not protective in a murine vulvovaginitis model. Farnesol was not beneficial in combination with fluconazole for fluconazole-susceptible isolates, but partially increased fluconazole activity against one fluconazole-resistant isolate, but not the other one.

The Synergistic Effect of Azoles and Fluoxetine against Resistant Candida albicans Strains Is Attributed to Attenuating Fungal Virulence.

This study evaluated the synergistic effects of the selective serotonin reuptake inhibitor, fluoxetine, in combination with azoles against Candida albicans both in vitro and in vivo and explored the underlying mechanism. MICs, sessile MICs, and time-kill curves were determined for resistant C. albicans Galleria mellonella was used as a nonvertebrate model for determining the efficacy of the drug combinations against C. albicans in vivo For the mechanism study, gene expression levels of the SAP gene family were determined by reverse transcription (RT)-PCR, and extracellular phospholipase activities were detected in vitro by the egg yolk agar method. The combinations resulted in synergistic activity against C. albicans strains, but the same effect was not found for the non-albicans Candida strains. For the biofilms formed over 4, 8, and 12 h, synergism was seen for the combination of fluconazole and fluoxetine. In addition, the time-kill curves confirmed the synergism dynamically. The results of the G. mellonella studies agreed with the in vitro analysis. In the mechanism study, we observed that fluconazole plus fluoxetine caused downregulation of the gene expression levels of SAP1 to SAP4 and weakened the extracellular phospholipase activities of resistant C. albicans The combinations of azoles and fluoxetine showed synergistic effects against resistant C. albicans may diminish the virulence properties of C. albicans.