Oral azole drugs as systemic antifungal therapy

Combination therapy of itraconazole and an acylhydrazone derivative (D13) for the treatment of sporotrichosis in cats

Acylhydrazone (AH) derivatives represent a novel category of anti-fungal medications that exhibit potent activity against Sporothrix sp., both in vitro and in a murine model of sporotrichosis. In this study, we demonstrated the anti-fungal efficacy of the AH derivative D13 [4-bromo-N'-(3,5-dibromo-2-hydroxybenzylidene)-benzohydrazide] against both planktonic cells and biofilms formed by Sporothrix brasiliensis. In a clinical study, the effect of D13 was then tested in combination with itraconazole (ITC), with or without potassium iodide, in 10 cats with sporotrichosis refractory to the treatment of standard of care with ITC. Improvement or total clinical cure was achieved in five cases after 12 weeks of treatment. Minimal abnormal laboratory findings, e.g., elevation of alanine aminotransferase, were observed in four cats during the combination treatment and returned to normal level within a week after the treatment was ended. Although highly encouraging, a larger and randomized controlled study is required to evaluate the effectiveness and the safety of this new and exciting drug combination using ITC and D13 for the treatment of feline sporotrichosis.

IMPORTANCE

This paper reports the first veterinary clinical study of an acylhydrazone anti-fungal (D13) combined with itraconazole against a dimorphic fungal infection, sporotrichosis, which is highly endemic in South America in animals and humans. Overall, the results show that the combination treatment was efficacious in ~50% of the infected animals. In addition, D13 was well tolerated during the course of the study. Thus, these results warrant the continuation of the research and development of this new class of anti-fungals.

Antifungal climbazole alters androgenic pathways in mammalian cells

Among antifungal agents used in pharmaceuticals and personal care products, the synthetic azole climbazole (CBZ; 1-(4-Chlorophenoxy)-1-(imidazol-1-yl)-3,3-dimethylbutan-2-one) acts on the fungus Malassezia. Despite concerns surrounding its effects on health, based on alterations to reproduction and steroidogenesis found in fish, little is known about its mechanism of action as an endocrine disrupting chemical (EDC) in mammalian cells. In this study, using OECD test guidelines, we investigated the effects of CBZ (i) in H295R cells, on the production of estradiol and testosterone, as well as intermediate metabolites in steroidogenesis pathway, and (ii) in HeLa9903 and AR-EcoScreen cell lines, on the transactivation of estrogen and androgen receptors. Our results are the first evidence in H295R cells, that CBZ treatment (from 0.3 μM) decreased secreted levels of testosterone and estradiol. This was associated with reduced 17α-hydroxypregnenolone and 17α-hydroxyprogesterone levels. The altered levels of these metabolites were associated with a decrease in cytochrome P450 17α-hydroxylase/17,20-lyase (Cyp17A1) activity without any effect on its protein level. CBZ was also found to exert antagonistic effects toward androgen and estrogen α receptors. These results give insights into the toxicological mechanism of action of CBZ. Many azoles share structural similarities; therefore, caution should be adopted due to their potential toxicity.

First case of Rhinocladiella mackenziei brain abscess in Turkey: Case report and review of the literature

Rhinocladiella mackenziei is a highly neurotropic fungus, mainly reported from the Middle East. However, in recent years, there have been some cases from outside this region. We described an additional fatal case of R. mackenziei cerebral infection for the first time from Turkey and made a literature review of all previously reported cases. During 34 years (1988-2022), there have been 42 R. mackenziei brain abscess cases. Most patients have been reported from Saudi Arabia (n = 14, 33.3%). It is noteworthy that 40.5% of patients, including our case, were immunocompetent at initial diagnosis and mostly presented with a single lesion (n = 10, 23.8%). The most frequent comorbidities were solid organ transplant (n = 9, 21.4%), diabetes mellitus (n = 6, 14.3%), malignancy (n = 6, 14.3%) and prior surgery (n = 3, 7.1%). The most commonly used initial antifungal regimen were amphotericin B together with itraconazole (n = 9, 21.4%), combinations of lipid preparations of amphotericin B, voriconazole and/or posaconazole (n = 9, 21.4%) and amphotericin B alone (n = 8, 19%). Although both surgical procedures and antifungal medication in the majority of patients were performed, mortality rates remained high (90.4%). The area at risk of R. mackenziei cerebral abscess cases extends to other countries. Clinicians should be aware of this emerging disease and take a detailed travel history in patients with atypical and undocumented brain abscesses. Our case confirms the hypothesis that this fungus might spread more widely than previously predicted regions.

The effect of conazoles on reproductive organs structure and function – a review

Conazoles are azole antifungals used in agricultural and pharmaceutical products. Exposure to conazole fungicides leads to several toxic endpoints, including reproductive and endocrine. The results of animal experiments have shown that various conazole fungicides at high doses affect the structure and functions of reproductive organs. In males, adverse effects of conazole fungicides are manifested in the testes, prostate, sperm viability, fertility and sexual behaviour. Reduced testis weight, testis atrophy and reduced or absent sperm production were frequently observed. In female genitalia, structural changes in the ovaries and uterus have been observed. The extent of the changes depends on the dose and duration of treatment. Triazoles affected the expression of multiple genes involved in steroid hormone metabolism and modulate enzyme activity of multiple cytochrome P450 (CYP) and other metabolic enzymes in mammalian liver and other tissues. Conazole fungicides act as endocrine disruptors. Conazoles have been reported to reduce oestradiol and testosterone production and to increase progesterone concentration, indicating the inhibition of enzymes involved in the conversion of progesterone to testosterone. The reproductive effects are consistent with impairment of testosterone homeostasis. The disruption in steroid homeostasis is a common mode of action, leading to abnormal reproductive development and diminished reproductive function. At high doses, azole fungicides affect reproductive organs and fertility in several species.

Arylacetamide deacetylase knockout mice are sensitive to ketoconazole-induced hepatotoxicity and adrenal insufficiency

Orally administered ketoconazole may rarely induce liver injury and adrenal insufficiency. A metabolite formed by arylacetamide deacetylase (AADAC)-mediated hydrolysis has been observed in cellulo studies, and it is relevant to ketoconazole-induced cytotoxicity. This study tried to examine the significance of AADAC in ketoconazole-induced toxicity in vivo using Aadac knockout mice. Oral administration of 150 mg/kg ketoconazole resulted in the area under the plasma concentration-time curve values of ketoconazole and N-deacetylketoconazole, a hydrolyzed metabolite of ketoconazole, in Aadac knockout mice being significantly higher and lower than those in wild-type mice, respectively. With the administration of ketoconazole (300 mg/kg/day) for 7 days, Aadac knockout mice showed higher mortality (100%) than wild-type mice (42.9%), and they also showed significantly higher plasma alanine transaminase and lower corticosterone levels, thus representing liver injury and steroidogenesis inhibition, respectively. It was suggested that a higher plasma ketoconazole concentration likely accounts for the inhibition of the synthesis of corticosterone, which has anti-inflammatory effects, in the adrenal gland in Aadac KO mice. In Aadac knockout mice, hepatic mRNA levels of immune- and inflammation-related factors were increased by the administration of 300 mg/kg ketoconazole, and the increase was restored by the replenishment of corticosterone (40 mg/kg, s.c.) along with recoveries of plasma alanine transaminase levels. In conclusion, Aadac defects exacerbate ketoconazole-induced liver injury by inhibiting glucocorticoid synthesis and enhancing the inflammatory response. This in vivo study revealed that the hydrolysis of ketoconazole by AADAC can mitigate ketoconazole-induced toxicities.

Structural Insights into the Azole Resistance of the Candida albicans Darlington Strain Using Saccharomyces cerevisiae Lanosterol 14α-Demethylase as a Surrogate

Target-based azole resistance in Candida albicans involves overexpression of the ERG11 gene encoding lanosterol 14α-demethylase (LDM), and/or the presence of single or multiple mutations in this enzyme. Overexpression of Candida albicans LDM (CaLDM) Y132H I471T by the Darlington strain strongly increased resistance to the short-tailed azoles fluconazole and voriconazole, and weakly increased resistance to the longer-tailed azoles VT-1161, itraconazole and posaconazole. We have used, as surrogates, structurally aligned mutations in recombinant hexahistidine-tagged full-length Saccharomyces cerevisiae LDM6×His (ScLDM6×His) to elucidate how differential susceptibility to azole drugs is conferred by LDM of the C. albicans Darlington strain. The mutations Y140H and I471T were introduced, either alone or in combination, into ScLDM6×His via overexpression of the recombinant enzyme from the PDR5 locus of an azole hypersensitive strain of S. cerevisiae. Phenotypes and high-resolution X-ray crystal structures were determined for the surrogate enzymes in complex with representative short-tailed (voriconazole) and long-tailed (itraconazole) triazoles. The preferential high-level resistance to short-tailed azoles conferred by the ScLDM Y140H I471T mutant required both mutations, despite the I471T mutation conferring only a slight increase in resistance. Crystal structures did not detect changes in the position/tilt of the heme co-factor of wild-type ScLDM, I471T and Y140H single mutants, or the Y140H I471T double-mutant. The mutant threonine sidechain in the Darlington strain CaLDM perturbs the environment of the neighboring C-helix, affects the electronic environment of the heme, and may, via differences in closure of the neck of the substrate entry channel, increase preferential competition between lanosterol and short-tailed azole drugs.

Preparation of Topical Itraconazole with Enhanced Skin/Nail Permeability and In Vivo Antifungal Efficacy against Superficial Mycosis

In this study, a stable and highly skin-permeable topical delivery system for itraconazole (ITZ) was designed to provide effective treatment against superficial mycosis. Herein, ITZ was incorporated into a solution composed of ethanol, benzyl alcohol, hydrochloric acid, Transcutol P, and cyclomethicone as a delivery vehicle, solubilizer, protonating agent, permeation enhancer, and spreading agent, respectively. At 72 h, the optimal topical ITZ formulation (ITZ–TF#11) exhibited 135% enhanced skin permeability, which led to increases in drug deposition in the stratum corneum, epidermis, and dermis of 479%, 739%, and 2024%, respectively, compared with the deposition of 1% ITZ in ethanol (control). Moreover, on day 7, ITZ–TF#11 demonstrated 2.09- and 2.30-fold enhanced nail flux and drug deposition, compared with the control. At a dose of 40 mg/kg/day, ITZ–TF#11 showed 323% greater lesion recovery, a 165% lower mean erythema severity score, and a 37% lower mean logarithm of viable fungal cells in skin in the treated area, compared with mice that received oral ITZ at the same dose. Overall, the findings imply that ITZ–TF#11 is a superior alternative to oral ITZ for treatment of superficial mycosis.

Fresh Molecular Concepts to Extend the Lifetimes of Old Antimicrobial Drugs

Antimicrobial drug development generally initiates with target identification and mode of action studies. Often, emergence of resistance and/or undesired side effects that are discovered only after prolonged clinical use, result in discontinuation of clinical use. Since the cost and time required for improvement of existing drugs are considerably lower than those required for the development of novel drugs, academic and pharmaceutical company researchers pursue this direction. In this account we describe selected examples of how chemical probes generated from antimicrobial drugs and chemical and enzymatic modifications of these drugs have been used to modify modes of action, block mechanisms of resistance, or reduce side effects, improving performance. These examples demonstrate how new and comprehensive mechanistic insights can be translated into fresh concepts for development of next-generation antimicrobial agents.

Safety and nonclinical and clinical pharmacokinetics of PC945, a novel inhaled triazole antifungal agent

PC945 is a novel antifungal triazole formulated for nebulized delivery to treat lung Aspergillus infections. Pharmacokinetic and safety profiles from nonclinical studies and clinical trials in healthy subjects, and subjects with mild asthma were characterized. Toxicokinetics were assessed following daily 2-hour inhalation for 14 days. Potential for drug-drug interactions was evaluated using pooled human liver microsomes. Clinical safety and pharmacokinetics were assessed following (a) single inhaled doses (0.5-10 mg), (b) 7-day repeat doses (5 mg daily) in healthy subjects; (c) a single dose (5 mg) in subjects with mild asthma. Cmax occurred 4 hours (rats) or immediately (dogs) after a single dose. PC945 lung concentrations were substantially higher (>2000-fold) than those in plasma. PC945 only inhibited CYP3A4/5 substrate metabolism (IC50 : 1.33 µM [testosterone] and 0.085 µM [midazolam]). Geometric mean Cmax was 322 pg/mL (healthy subjects) and 335 pg/mL (subjects with mild asthma) 4-5 hours (median tmax ) after a single inhalation (5 mg). Following repeat, once daily inhalation (5 mg), Day 7 Cmax was 951 pg/mL (0.0016 µM) 45 minutes after dosing. Increases in Cmax and AUC0-24h were approximately dose-proportional (0.5-10 mg). PC945 administration was well tolerated in both healthy subjects and subjects with mild asthma. Treatment-emergent adverse events were mild/moderate and resolved before the study ended. No clinically significant lung function changes were observed. PC945 pharmacokinetics translated from nonclinical species to humans showed slow absorption from lungs and low systemic exposure, thereby limiting the potential for adverse side effects and drug interactions commonly seen with systemically delivered azoles.

In Vivo Efficacy of TXCB, a Vietnamese Herbal Medicine Prescription, on Seminal Quality, Serum Testosterone, and Malondialdehyde Concentration in Rabbits

The efficacy of Truong Xuan Cao Bang (TXCB), a Vietnamese herbal medicine prescription, on the quality of semen, serum testosterone (TES), and malondialdehyde (MDA) concentrations in rabbits whose reproductive ability were impaired by fluconazole was investigated. Mature male rabbits were randomly assigned into control (G1), fluconazole (G2), fluconazole and 180 mg/kg/day (G3), and 360 mg/kg/day TXCB (G4) groups. The reaction time (RT), ejaculate volume (EV), sperm concentration (SC), total sperm output (TSO), total sperm motility (TSM), progressive sperm motility (PSM), nonprogressive sperm motility (NPSM), sperm immobility (SIM), dead sperm (DS), and abnormal sperm (AS) levels were determined after TXCB administration. After 60 days, G3 showed a significant increase in serum TES and a significant decrease in the concentrations of serum MDA (SMDA) and seminal plasma MDA (SPMDA) compared with G1, in addition to increase in EV, SC, TSO, TSM, PSM, and serum TES, and decrease in RT, SIM, DS, AS, SMDA, and SPMDA compared with G2. G4 showed a steep rise in EV, SC, and serum TES and a downturn in DS, SMDA, and SPMDA compared with G1, and, compared with G2, a significant increase in EV, SC, TSO, TSM, PSM, and serum TES and a significant decrease in RT, SIM, DS, AS, SMDA, and SPMDA. Taken together, TXCB rehabilitates and simultaneously enhances spermatogenesis in rabbits whose reproductive ability was impaired by fluconazole.

Overcoming cancer therapeutic bottleneck by drug repurposing

Ever present hurdles for the discovery of new drugs for cancer therapy have necessitated the development of the alternative strategy of drug repurposing, the development of old drugs for new therapeutic purposes. This strategy with a cost-effective way offers a rare opportunity for the treatment of human neoplastic disease, facilitating rapid clinical translation. With an increased understanding of the hallmarks of cancer and the development of various data-driven approaches, drug repurposing further promotes the holistic productivity of drug discovery and reasonably focuses on target-defined antineoplastic compounds. The "treasure trove" of non-oncology drugs should not be ignored since they could target not only known but also hitherto unknown vulnerabilities of cancer. Indeed, different from targeted drugs, these old generic drugs, usually used in a multi-target strategy may bring benefit to patients. In this review, aiming to demonstrate the full potential of drug repurposing, we present various promising repurposed non-oncology drugs for clinical cancer management and classify these candidates into their proposed administration for either mono- or drug combination therapy. We also summarize approaches used for drug repurposing and discuss the main barriers to its uptake.

Oral administration of voriconazole with surgical fungal plaque debridement for the treatment of sinonasal aspergillosis with cribriform plate lysis in three dogs

CASE DESCRIPTION

3 dogs with chronic sinonasal signs (sneezing, nasal discharge, or epistaxis [or a combination of signs]) were examined.

CLINICAL FINDINGS

For all 3 dogs, CT revealed variable degrees of nasal turbinate destruction and frontal sinus involvement with cribriform plate lysis. Fungal plaques were detected during rhinoscopy or sinusoscopy. Results of fungal culture (2 dogs) or cytologic examination of a plaque specimen (1 dog) supported a diagnosis of sinonasal aspergillosis.

TREATMENT AND OUTCOME

All dogs underwent surgical rhinotomy or sinusotomy (or both) for fungal plaque debridement followed by oral treatment with voriconazole and periodic physical examinations, clinicopathologic analyses, and assessments of serum drug concentrations for a period ≥ 22 weeks. All dogs had considerable to complete reduction of their clinical signs and tolerated voriconazole treatment with minimal adverse effects. Adverse effects included development of reversible neurotoxicosis (associated with high serum voriconazole concentration) and mildly high serum liver enzyme activities. The dosage of voriconazole administered to achieve therapeutic serum concentrations (2.5 to 3.3 mg/kg [1.1 to 1.5 mg/lb], PO, q 12 h) was substantially lower than dosages suggested by previously published studies in dogs. The 3 dogs remained clinically normal or had mild clinical signs after voriconazole discontinuation for follow-up times of 6 to 15 months.

CLINICAL RELEVANCE

Findings in these 3 dogs indicated that surgical fungal plaque debridement followed by oral treatment with voriconazole may be an effective treatment option for dogs with sinonasal aspergillosis and cribriform plate lysis. Further evaluation of this treatment regimen with repeated CT examinations and longer follow-up times is warranted.

The potential risk factors of nephrotoxicity during vancomycin therapy in Chinese adult patients

OBJECTIVE

To evaluate potential risk factors that may make patients susceptible to nephrotoxicity in those concomitantly receiving vancomycin in the hospital.

METHODS

This was a single-centre retrospective analysis of patients treated with vancomycin for gram-positive or mixed infections in the Renmin Hospital of Wuhan University from January 2017 to May 2018. All of them were treated for ≥48 hours and had no kidney disease. Nephrotoxicity refers to acute kidney diseases and disorders after the use of vancomycin, and includes acute kidney injury. Univariate analysis and binary logistic regression analysis with the forward stepwise method were used to assess the risk factors associated with nephrotoxicity.

RESULTS

Of the 790 patients treated with vancomycin, only 257 patients met the inclusion criteria, and 40 (15.6%) subjects developed nephrotoxicity. Significant differences (p<0.05) were seen in the number of combined antimicrobials (p=0.012), dose adjustment (p<0.001), more than three antimicrobials (p=0.015), monitoring trough concentrations (p=0.001), furosemide (p<0.001), torasemide (p<0.001), cefoperazone sodium tazobactam sodium (p=0.039), voriconazole (p=0.012) and ganciclovir (p=0.008). Regression analysis further indicated that furosemide (OR 7.983, p<0.001) and torasemide (OR 3.496, p<0.001) were risk factors for vancomycin nephrotoxicity. Diabetes mellitus (OR 3.062, p=0.035), voriconazole (OR 3.515, p=0.020) and fluconazole (OR 3.326, p=0.018) might be also risk factors.

CONCLUSION

Fluconazole and voriconazole might be potential risk factors for vancomycin nephrotoxicity, besides furosemide and torasemide. It is not recommended to use imipenem cilastatin sodium and vancomycin at the same time. If necessary, meropenem may be safer. Appropriate combination drugs, cautious initial dose or timely dose adjustment might reduce the occurrence of nephrotoxicity when using vancomycin.

Nystatin Prophylaxis: Its Inability to Prevent Fungal Peritonitis in Patients on Continuous Ambulatory Peritoneal Dialysis

Objective

To evaluate the potential effectiveness of nystatin as prophylaxis for fungal peritonitis (FP) in patients on continuous ambulatory peritoneal dialysis (CAPD).

Design

This historically controlled study was designed to investigate the effectiveness of nystatin in the prevention of FP. For this purpose we compared the incidence of FP among 240 (new and prevalent) CAPD patients between January 1996 and November 1996 (period A) with its incidence in 240 new and prevalent CAPD patients in our program between January 1997 and November 1997 (period B) when nystatin prophylaxis was used. There were 2400 patient-months in each period. Nystatin (500000 IU four times per day), was given orally at the beginning of other antibiotic therapy (usually for peritonitis) and continued for 5 days after the end of the antibiotic therapy.

Results

During period A, 133 peritonitis episodes were recorded, and during period B, 99 episodes were recorded. Six episodes of FP were identified in over 2400 patient months of period A, and 12 in over 2400 patient-months of period B. This difference was not statistically significant. Three episodes of antibiotic-related FP were seen in period A, and four in period B. The remaining episodes arose de novo, that is, unrelated to the use of antibiotics. We observed no side effects for nystatin.

Conclusion

In CAPD patients the use of nystatin, a nonabsorbable antifungal agent, as prophylaxis in every instance of peritonitis or other indications for antibiotics, did not lower the incidence of fungal peritonitis.

Identification of novel antifungal agents: antimicrobial evaluation, SAR, ADME-Tox and molecular docking studies of a series of imidazole derivatives

Thirty-four imidazole-based compounds synthesized by one-pot catalytic method were evaluated for their antifungal and antibacterial activities against several fungal and bacterial strains. None of the compounds had antibacterial activity. Interestingly, compounds 1, 2, 3, 10 and 15 displayed a strong antifungal activity against all the tested fungal species, while compounds 5, 7, 9, 11, 21 and 27 showed a moderate antifungal activity. To better understand the biological activity of the most active compounds ADME-Tox and molecular docking studies were carried out. Interestingly, compounds 1, 2, 3, 7, 10 and 15 showed excellent bioavailability. In addition, compounds 1, 2 and 3, exhibited good toxicity profiles. Docking studies of the two most active compounds 2 (IC50 of 95 ± 7.07 μM) and 10 (IC50 of 235 ± 7.07 μM) suggested that they might act by inhibiting the fungal lanosterol 14α-demethylase. Therefore, these novel antifungal agents merit further characterization for the development of new antifungal therapeutics.

Fluconazole Increases Osmotic Water Transport in Renal Collecting Duct through Effects on Aquaporin-2 Trafficking

BACKGROUND

Arginine-vasopressin (AVP) binding to vasopressin V2 receptors promotes redistribution of the water channel aquaporin-2 (AQP2) from intracellular vesicles into the plasma membrane of renal collecting duct principal cells. This pathway fine-tunes renal water reabsorption and urinary concentration, and its perturbation is associated with diabetes insipidus. Previously, we identified the antimycotic drug fluconazole as a potential modulator of AQP2 localization.

METHODS

We assessed the influence of fluconazole on AQP2 localization in vitro and in vivo as well as the drug's effects on AQP2 phosphorylation and RhoA (a small GTPase, which under resting conditions, maintains F-actin to block AQP2-bearing vesicles from reaching the plasma membrane). We also tested fluconazole's effects on water flow across epithelia of isolated mouse collecting ducts and on urine output in mice treated with tolvaptan, a VR2 blocker that causes a nephrogenic diabetes insipidus-like excessive loss of hypotonic urine.

RESULTS

Fluconazole increased plasma membrane localization of AQP2 in principal cells independent of AVP. It also led to an increased AQP2 abundance associated with alterations in phosphorylation status and ubiquitination as well as inhibition of RhoA. In isolated mouse collecting ducts, fluconazole increased transepithelial water reabsorption. In mice, fluconazole increased collecting duct AQP2 plasma membrane localization and reduced urinary output. Fluconazole also reduced urinary output in tolvaptan-treated mice.

CONCLUSIONS

Fluconazole promotes collecting duct AQP2 plasma membrane localization in the absence of AVP. Therefore, it might have utility in treating forms of diabetes insipidus (e.g., X-linked nephrogenic diabetes insipidus) in which the kidney responds inappropriately to AVP.

Can Saccharomyces cerevisiae keep up as a model system in fungal azole susceptibility research?

The difficulty of manipulation and limited availability of genetic tools for use in many pathogenic fungi hamper fast and adequate investigation of cellular metabolism and consequent possibilities for antifungal therapies. S. cerevisiae is a model organism that is used to study many eukaryotic systems. In this review, we analyse the potency and relevance of this model system in investigating fungal susceptibility to azole drugs. Although many of the concepts apply to multiple pathogenic fungi, for the sake of simplicity, we will focus on the validity of using S. cerevisiae as a model organism for two Candida species, C. albicans and C. glabrata. Apart from the general benefits, we explore how S. cerevisiae can specifically be used to improve our knowledge on azole drug resistance and enables fast and efficient screening for novel drug targets in combinatorial therapy. We consider the shortcomings of the model system, yet conclude that it is still opportune to use S. cerevisiae as a model system for pathogenic fungi in this era.

Candidiasis: Red and White Manifestations in the Oral Cavity

Candidiasis is a very common malady in the head neck region. This review will concentrate on intraoral, pharyngeal and perioral manifestations and treatment. A history of the origins associated with candidiasis will be introduced. In addition, oral conditions associated with candidiasis will be mentioned and considered. The various forms of oral and maxillofacial candidiasis will be reviewed to include pseudomembranous, acute, chronic, median rhomboid glossitis, perioral dermatitis, and angular cheilitis. At the end of this review the clinician will be better able to diagnose and especially treat candidal overgrowth of the oral facial region. Of particular interest to the clinician are the various treatment modalities with appropriate considerations for side effects.

Pre-Existing Liver Disease and Toxicity of Antifungals

Pre-existing liver disease in patients with invasive fungal infections further complicates their management. Altered pharmacokinetics and tolerance issues of antifungal drugs are important concerns. Adjustment of the dosage of antifungal agents in these cases can be challenging given that current evidence to guide decision-making is limited. This comprehensive review aims to evaluate the existing evidence related to antifungal treatment in individuals with liver dysfunction. This article also provides suggestions for dosage adjustment of antifungal drugs in patients with varying degrees of hepatic impairment, after accounting for established or emerging pharmacokinetic–pharmacodynamic relationships with regard to antifungal drug efficacy in vivo.

Wahab N, Mustafa N, Sukor N, Kamaruddin NA. Fluconazole as a Safe and Effective Alternative to Ketoconazole in Controlling Hypercortisolism of Recurrent Cushing's Disease: A Case Report

INTRODUCTION

Ketoconazole has long been the first-line medical therapy for controlling hypercortisolism secondary to either pituitary or adrenal pathology. However, it is largely unavailable in most countries. As a result, we have turned to fluconazole as a viable alternative in view of its favourable safety profile.

CASE PRESENTATION

A 50-year-old lady developed recurrent Cushing's disease after being in remission following transsphenoidal surgery (TSS) for a left pituitary microadenoma 16 years ago. The repeat MRI showed a right pituitary microadenoma (1.7 mm × 1.3 mm) for which she underwent a second TSS. However, she continued to have persistent hypercortisolism despite repeated MRIs showing absence of tumour recurrence. She refused bilateral adrenalectomy and external radiotherapy. Ketoconazole was commenced at 200 mg twice daily for disease control but this was hindered by intolerable side effects including pruritus and skin exfoliation. In the meantime, she suffered a right hypertensive basal ganglia hemorrhage. Treatment was subsequently switched to cabergoline and the dose titrated to 0.5 mg daily. Fluconazole 400 mg daily was later added to control the persistent disease. Her clinical and biochemical parameters improved markedly three months after the addition of fluconazole. No adverse event was reported. Her disease has remained stable for the last 15 months up until the time of the recent clinic review.

CONCLUSIONS

This case demonstrates the long-term efficacy of fluconazole in tandem with cabergoline for the control of recurrent Cushing's disease.

Insight into the Significance of Aspergillus fumigatus cyp51A Polymorphisms

Triazole antifungal compounds are the first treatment choice for invasive aspergillosis. However, in the last decade the rate of azole resistance among Aspergillus fumigatus strains has increased notoriously. The main resistance mechanisms are well defined and mostly related to point mutations of the azole target, 14-α sterol demethylase (cyp51A), with or without tandem repeat integrations in the cyp51A promoter. Furthermore, different combinations of five Cyp51A mutations (F46Y, M172V, N248T, D255E, and E427K) have been reported worldwide in about 10% of all A. fumigatus isolates tested. The azole susceptibility profile of these strains shows elevated azole MICs, although on the basis of the azole susceptibility breakpoints, these strains are not considered azole resistant. The purpose of the study was to determine whether these cyp51A polymorphisms (single nucleotide polymorphisms [SNPs]) are responsible for the azole susceptibility profile and whether they are reflected in a poorer azole treatment response in vivo that could compromise patient treatment and outcome. A mutant with a cyp51A deletion was generated and became fully susceptible to all azoles tested. Also, three cyp51A gene constructions with different combinations of SNPs were generated and reintroduced into an azole-susceptible wild-type (WT) strain (the ΔakuB^KU80 strain). The alternative model host Galleria mellonella was used to compare the virulence and voriconazole response of G. mellonella larvae infected with A. fumigatus strains with WT cyp51A or cyp51A with SNPs. All strains were pathogenic in G. mellonella larvae, although they did not respond similarly to voriconazole therapeutic doses. Finally, the full genomes of these strains were sequenced and analyzed in comparison with those of A. fumigatus WT strains, revealing that they belong to different strain clusters or lineages.

Localizing Antifungal Drugs to the Correct Organelle Can Markedly Enhance their Efficacy

A critical aspect of drug design is optimal target inhibition by specifically delivering the drug molecule not only to the target tissue or cell but also to its therapeutically active site within the cell. This study demonstrates, as a proof of principle, that drug efficacy can be increased considerably by a structural modification that targets it to the relevant organelle. Specifically, by varying the fluorescent dye segment an antifungal azole was directed from the fungal cell mitochondria to the endoplasmic reticulum (ER), the organelle that harbors the drug target. The ER-localized azole displayed up to two orders of magnitude improved antifungal activity and also dramatically reduced the growth of drug-tolerant fungal subpopulations in a panel of Candida species, which are the most prevalent causes of serious human fungal infections. The principle underlying the "target organelle localization" approach provides a new paradigm to improve drug potency and replenish the limited pipeline of antifungal drugs.

Population Pharmacokinetic Modeling to Describe the Total Plasma and Free Brain Levels of Fluconazole in Healthy and Cryptococcus neoformans Infected Rats: How Does the Infection Impact the Drug's Levels on Biophase?

PURPOSE

The present work aimed to evaluate the influence of experimental meningitis caused by C. neoformans on total plasma and free brain concentrations of fluconazole (FLC) in Wistar rats.

METHOD

The infection was induced by the administration of 100 μL of inoculum (1.10⁵ CFU) through the tail vein. Free drug in the brain was assessed by microdialisys (μD). Blood and μD samples were collected at pre-determined time points up to 12 h after intravenous administration of FLC (20 mg/kg) to healthy and infected rats. The concentration-time profiles were analyzed by non-compartmental and population pharmacokinetics approaches.

RESULTS

A two-compartmental popPK model was able to simultaneously describe plasma and free drug concentrations in the brain for both groups investigated. Analysis of plasma and μD samples showed a better FLC distribution on the brain of infected than healthy animals (1.04 ± 0.31 vs 0.69 ± 0.14, respectively). The probability of target attainment was calculated by Monte Carlo simulations based on the developed popPK model for 125 mg/kg dose for rats and 400-2000 mg for humans.

CONCLUSIONS

FLC showed a limited use in monotherapy to the treatment of criptoccocosis in rats and humans to value of MIC >8 μg/mL.

Cerebral phaeohyphomycosis due to Rhinocladiella mackenziei in Persian Gulf region: A case and review

Cerebral phaeohyphomycosis is frequently a fatal disease caused by truly neurotropic dematiaceous fungi. Although rare, this infection occurs especially among immunocompetent patients, and the clinical symptoms are often misdiagnosed as a cerebral tumour or bacterial brain abscess. The appropriate diagnosis and therapy of cerebral infections by melanized fungi are very challenging if they are caused by mysterious fungi with unknown ecological niche. We reported the second case of cerebral phaeohyphomycosis due to Rhinocladiella mackenziei in Iran and the first culture-confirmed case. In this report, the differential diagnosis and histopathological findings are discussed and a review of the literature is provided.

Real-Time Imaging of the Azole Class of Antifungal Drugs in Live Candida Cells

Azoles are the most commonly used class of antifungal drugs, yet where they localize within fungal cells and how they are imported remain poorly understood. Azole antifungals target lanosterol 14α-demethylase, a cytochrome P450, encoded by ERG11 in Candida albicans, the most prevalent fungal pathogen. We report the synthesis of fluorescent probes that permit visualization of antifungal azoles within live cells. Probe 1 is a dansyl dye-conjugated azole, and probe 2 is a Cy5-conjugated azole. Docking computations indicated that each of the probes can occupy the active site of the target cytochrome P450. Like the azole drug fluconazole, probe 1 is not effective against a mutant that lacks the target cytochrome P450. In contrast, the azole drug ketoconazole and probe 2 retained some antifungal activity against mutants lacking the target cytochrome P450, implying that both act against more than one target. Both fluorescent azole probes colocalized with the mitochondria, as determined by fluorescence microscopy with MitoTracker dye. Thus, these fluorescent probes are useful molecular tools that can lead to detailed information about the activity and localization of the important azole class of antifungal drugs.

Influence of Experimental Cryptococcal Meningitis in Wistar Rats on Voriconazole Brain Penetration Assessed by Microdialysis

To make advances in the treatment of cryptococcal meningitis, it is crucial to know a given drug's free fraction that reaches the biophase. In the present study, we applied microdialysis (μD) as a tool to determine the free levels reached by voriconazole (VRC) in the brains of healthy and Cryptococcus neoformans-infected rats. The infection was induced by the intravenous (i.v.) administration of 1 × 105 CFU of yeast. The dose administered was 5 mg/kg (of body weight) of VRC, given i.v. Plasma and microdialysate samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and LC-UV methods. The free brain/free plasma ratio (fT) and population pharmacokinetic (popPK) analyses were performed to evaluate the impact of infection on PK parameters of the drug. The brain penetration ratio showed an increase on brain exposure in infected animals (fThealthy = 0.85 versus fTinfected = 1.86). The structural PK model with two compartments and Michaelis-Menten (MM) elimination describes the VRC concentration-time profile in plasma and tissue simultaneously. The covariate infection was included in volume of distribution in the peripheral compartment in healthy animals (V2) and maximum rate of metabolism (VM ). The levels reached in infected tissues were higher than the values described for MIC of VRC for Cryptococccus neoformans (0.03 to 0.5 μg ml-1), indicating its great potential to treat meningitis associated with C. neoformans.

Prenatal exposure to antifungal medication may change anogenital distance in male offspring: a preliminary study

BACKGROUND

Vaginal candidiasis is frequent among pregnant women and it is treated with anti-fungal medication (conazoles). Conazoles have anti-androgenic properties and prenatal exposure in rodents is associated with a shorter (less masculine) anogenital distance (AGD) in male offspring. To our knowledge this has never been studied in humans.

METHOD

In the Odense Child Cohort pregnant women residing in Odense municipality, Denmark, were recruited at gestational age 8-16 weeks between 2010 and 2012. Of the eligible 2421 mother-child pairs, 812 mother-son pairs were included. Questionnaire data on medicine use were collected in first and third trimester and physical examination at age 3 month was performed. Ano-scrotal distance; measured from the centre of anus to the posterior base of scrotum (AGDas). Ano-cephalad distance; measured from the centre of anus to the cephalad insertion of the penis (AGDap) and penile width; measured at the base of the penis.

RESULTS

Eighty seven women had used antifungal medicine during pregnancy. Maternal use of oral fluconazole (n = 4) was associated with a 6.4 mm shorter AGDas (95% CI: -11.9;-0.9) in the male offspring. Use of antifungal vaginal tablets (n = 21), was associated with a non-significantly shorter AGDas (-1.9 mm; 95% CI: -4.3; 0.5) whereas exposure to vaginal cream (n = 23) was not associated to AGDas. Use of antifungal medicine in the window of genital development between 8 and 14 weeks of gestation was associated with a larger reduction in AGDas than exposure outside this window. Antifungal medicine intake was not associated with AGDap and penil width.

CONCLUSION

Our preliminary findings prompted us to hypothesize that maternal use of conazole antifungal medication during pregnancy may affect the masculinization of male offspring. If confirmed, pregnant women should be advised to use antifungal medicine with caution.

An overview of azoles targeting sterol 14α-demethylase for antileishmanial therapy

The azole antifungal drugs are an important class of chemotherapeutic agents with broad-spectrum of activity against yeasts and filamentous fungi, act in the ergosterol biosynthetic pathway through inhibition of the cytochrome P450-dependent enzyme sterol 14α-demethylase. Azole antifungals have also been repurposed for treatment of tropical protozoan infections including human leishmaniasis. Recent advances in molecular biology and computational chemistry areas have increased our knowledge about sterol biochemical pathway in Leishmania parasites. Based on the importance of sterol biosynthetic pathway in Leishmania parasites, we reviewed all studies reported on azoles for potential antileishmanial therapy along their structural and biological aspects. This review may help medicinal chemists for design of new azole-derived antileishmanial drugs.

Antifungal Therapy for Systemic Mycosis and the Nanobiotechnology Era: Improving Efficacy, Biodistribution and Toxicity

Fungal diseases have been emerging as an important public health problem worldwide with the increase in host predisposition factors due to immunological dysregulations, immunosuppressive and/or anticancer therapy. Antifungal therapy for systemic mycosis is limited, most of times expensive and causes important toxic effects. Nanotechnology has become an interesting strategy to improve efficacy of traditional antifungal drugs, which allows lower toxicity, better biodistribution, and drug targeting, with promising results in vitro and in vivo. In this review, we provide a discussion about conventional antifungal and nanoantifungal therapies for systemic mycosis.

New facets of antifungal therapy

Invasive fungal infections remain a major cause of morbidity and mortality in immunocompromised patients, and such infections are a substantial burden to healthcare systems around the world. However, the clinically available armamentarium for invasive fungal diseases is limited to 3 main classes (i.e., polyenes, triazoles, and echinocandins), and each has defined limitations related to spectrum of activity, development of resistance, and toxicity. Further, current antifungal therapies are hampered by limited clinical efficacy, high rates of toxicity, and significant variability in pharmacokinetic properties. New antifungal agents, new formulations, and novel combination regimens may improve the care of patients in the future by providing improved strategies to combat challenges associated with currently available antifungal agents. Likewise, therapeutic drug monitoring may be helpful, but its present use remains controversial due to the lack of available data. This article discusses new facets of antifungal therapy with a focus on new antifungal formulations and the synergistic effects between drugs used in combination therapy.

In vitro activity of kombucha tea ethyl acetate fraction against Malassezia species isolated from seborrhoeic dermatitis

BACKGROUND AND PURPOSE

Seborrheic dermatitis is a chronic and recurrent superficial dermatitis in which Malassezia species play an important role. There are different Malassezia species, which have been recently reported to be resistant to common antifungals. Natural sources can be useful alternatives to reduce the emergence of this resistance. Kombucha tea is believed to have potential antimicrobial properties. Regarding this, the present study aimed to investigate the antifungal activity of Kombucha tea ethyl acetate fraction (KEAF) against Malassezia species obtained from the patients with seborrheic dermatitis.

MATERIALS AND METHODS

A total of 23 clinical isolates were identified by direct microscopic examination and Tween assimilation, and then confirmed by DNA sequencing of ITS regions for Malassezia species. Kombucha tea was fractionated using ethyl acetate (1:2 v/v). The minimum inhibitory concentration (MIC) microdilution assay was used to evaluate the anti-Malssezia activity of KEAF at three concentrations of 10, 40, and 80 mg/mL.

RESULTS

The results of the DNA sequence analysis indicated that M. furfur (39.13%) was the predominant species, followed by M. globosa (30.43%), M. sloofie (13.04%), M. sympodialis (13.04%), and M. restricta (4.34%), respectively. Furthermore, KEAF showed inhibitory activity against Malassezia species. Accordingly, KEAF had the lowest and highest MIC value against M. sloofie and M. restricta, respectively. Moreover, the inhibitory effect of the extract was equivalent to that of ketoconazole at 4.8 µg/mL.

CONCLUSION

The findings of the current study highlighted the antifungal properties of KEAF. Therefore, this extract can be promoted as complementary medicine for the treatment of the infections caused by Malassezia.

Phytochemical Composition, Antifungal and Antioxidant Activity of Duguetia furfuracea A. St.-Hill

Background. Duguetia furfuracea is popular plant used in popular medicine. Hypothesis/Purpose. This claim evaluated the phytochemical composition of the hydroethanolic extract (HEDF), fractions of Duguetia furfuracea, and antioxidant and antifungal activity. Methods. The chemical profile was carried out by HPLC-DAD. The total phenolic contents and flavonoid components were determined by Folin-Ciocalteu and aluminium chloride reaction. The antioxidant activity was measured by scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and ferric reducing ability of plasma (FRAP) methods. The antifungal activity was determined by microdilution assay. Results. HPLC analysis revealed caffeic acid and rutin as major compounds (HEDF), caffeic acid and quercitrin (Mt-OH fraction), and quercitrin and isoquercitrin (Ac-OEt fraction). The highest levels of phenols and total flavonoids were found for Ac-OEt fraction, and the crude extract showed higher in vitro antioxidant potential. The antifungal activity showed synergic effect with fluconazole and EHDF against C. krusei, fluconazole and Mt-OH against C. krusei and C. tropicalis, and Ac-OE and fluconazole against C. albicans. Conclusion. The highest levels of phenols and total flavonoids were marked with antioxidant effect. This is the first report of bioactivity of the synergic effect of HEDF and fractions. More studies would be required to better clarify its mechanism of synergic action.

Fragment-Based Approaches to the Development of Mycobacterium tuberculosis CYP121 Inhibitors

The essential enzyme CYP121 is a target for drug development against antibiotic resistant strains of Mycobacterium tuberculosis. A triazol-1-yl phenol fragment 1 was identified to bind to CYP121 using a cascade of biophysical assays. Synthetic merging and optimization of 1 produced a 100-fold improvement in binding affinity, yielding lead compound 2 (KD = 15 μM). Deconstruction of 2 into its component retrofragments allowed the group efficiency of structural motifs to be assessed, the identification of more LE scaffolds for optimization and highlighted binding affinity hotspots. Structure-guided addition of a metal-binding pharmacophore onto LE retrofragment scaffolds produced low nanomolar (KD = 15 nM) CYP121 ligands. Elaboration of these compounds to target binding hotspots in the distal active site afforded compounds with excellent selectivity against human drug-metabolizing P450s. Analysis of the factors governing ligand potency and selectivity using X-ray crystallography, UV-vis spectroscopy, and native mass spectrometry provides insight for subsequent drug development.

Efficacy of nystatin for the treatment of oral candidiasis: a systematic review and meta-analysis

Objective

To systematically review and assess the efficacy, different treatment protocols (formulation, dosage, and duration), and safety of nystatin for treating oral candidiasis.

Methods

Four electronic databases were searched for trials published in English till July 1, 2015. Randomized controlled trials comparing nystatin with other antifungal therapies or a placebo were included. Clinical and/or mycological cure was the outcome evaluation. A meta-analysis or descriptive study on the efficacy, treatment protocols, and safety of nystatin was conducted.

Results

The meta-analysis showed that nystatin pastille was significantly superior to placebo in treating denture stomatitis. Nystatin suspension was not superior to fluconazole in treating oral candidiasis in infants, children, or HIV/AIDS patients. The descriptive investigations showed that administration of nystatin suspension and pastilles in combination for 2 weeks might achieve a higher clinical and mycological cure rate, and using the nystatin pastilles alone might have a higher mycological cure rate, when compared with using nystatin suspensions alone. Nystatin pastilles at a dose of 400,000 IU resulted in a significantly higher mycological cure rate than that administrated at a dose of 200,000 IU. Furthermore, treatment with nystatin pastilles for 4 weeks seemed to have better clinical efficacy than treatment for 2 weeks. Descriptive safety assessment showed that poor taste and gastrointestinal adverse reaction are the most common adverse effects of nystatin.

Conclusion

Nystatin pastille was significantly superior to placebo in treating denture stomatitis, while nystatin suspension was not superior to fluconazole in treating oral candidiasis in infants, children, or HIV/AIDS patients. Indirect evidence from a descriptive study demonstrated that administration of nystatin pastille alone or pastille and suspension in combination is more effective than that of suspension alone; prolonged treatment duration for up to 4 weeks can increase the efficacy of nystatin. More well designed and high quality randomized control studies are needed to confirm these findings.