Effect of proton pump inhibitors on susceptibility and melanogenesis of Sporothrix species.

Introduction. Sporotrichosis is a subcutaneous infection caused by dimorphic Sporothrix species embedded in the clinical clade. Fungi have virulence factors, such as biofilm and melanin production, which contribute to their survival and are related to the increase in the number of cases of therapeutic failure, making it necessary to search for new options.Gap statement. Proton pump inhibitors (PPIs) have already been shown to inhibit the growth and melanogenesis of other fungi.Aim. Therefore, this study aimed to evaluate the effect of the PPIs omeprazole (OMP), rabeprazole (RBP), esomeprazole, pantoprazole and lansoprazole on the susceptibility and melanogenesis of Sporothrix species, and their interactions with itraconazole, terbinafine and amphotericin B.Methodology. The antifungal activity of PPIs was evaluated using the microdilution method, and the combination of PPIs with itraconazole, terbinafine and amphotericin B was assessed using the checkerboard method. The assessment of melanogenesis inhibition was assessed using grey scale.Results. The OMP and RBP showed significant MIC results ranging from 32 to 256 µg ml-1 and 32 to 128 µg ml-1, respectively. Biofilms were sensitive, with a significant reduction (P<0.05) in metabolic activity of 52% for OMP and 50% for RBP at a concentration of 512 µg ml-1 and of biomass by 53% for OMP and 51% for RBP at concentrations of 512 µg ml-1. As for the inhibition of melanogenesis, only OMP showed inhibition, with a 54% reduction.Conclusion. It concludes that the PPIs OMP and RBP have antifungal activity in vitro against planktonic cells and biofilms of Sporothrix species and that, in addition, OMP can inhibit the melanization process in Sporothrix species.

Current situation of sporotrichosis in China.

Sporotrichosis, a mycosis resulting from cutaneous or subcutaneous infection with the dimorphic fungus Sporothrix, has been reported in China, particularly in the northeast region. In this review, we conducted a thorough examination of the recent advancements in sporotrichosis in China, encompassing aspects such as etiology, epidemiology, pathogenesis, clinical manifestations, diagnosis and treatment strategies. Within the Chinese context, fixed cutaneous sporotrichosis represents the prevailing clinical manifestation. Fungal culture stands as the gold standard for diagnosing sporotrichosis, while polymerase chain reaction techniques can enhance both the specificity and sensitivity of diagnosis. Besides conventional systemic antifungal agents, alternative modalities such as Chinese herbal medicines, photodynamic therapy and laser therapy show potential efficacy against sporotrichosis.

Sporotrichosis is a fungal infection on the skin. It is caused by a group of fungi called Sporothrix. Common symptoms are lesions on the skin, inflammatory papules, nodules and ulcers. These fungi live in the natural environment and cause infection by entering the body through a wound in the skin. China has a high prevalence of sporotrichosis, with northeast China the most seriously affected region. This review looks at the state of sporotrichosis in China.

Optimized expression of Peptidyl-prolyl cis/transisomerase cyclophilinB with prokaryotic toxicity from Sporothrix globosa.

Cyclophilin B (CypB), a significant member of immunophilins family with peptidyl-prolyl cis-trans isomerase (PPIase) activity, is crucial for the growth and metabolism of prokaryotes and eukaryotes. Sporothrix globosa (S. globosa), a principal pathogen in the Sporothrix complex, causes sporotrichosis. Transcriptomic analysis identified the cypB gene as highly expressed in S. globosa. Our previous study demonstrated that the recombinant Escherichia coli strain containing SgcypB gene failed to produce sufficient product when it was induced to express the protein, implying the potential toxicity of recombinant protein to the bacterial host. Bioinformatics analysis revealed that SgCypB contains transmembrane peptides within the 52 amino acid residues at the N-terminus and 21 amino acids near the C-terminus, and 18 amino acid residues within the cytoplasm. AlphaFold2 predicted a SgCypB 3D structure in which there is an independent PPIase domain consisting of a spherical extracellular part. Hence, we chose to express the extracellular domain to yield high-level recombinant protein with PPIase activity. Finally, we successfully produced high-yield, truncated recombinant CypB protein from S. globosa (SgtrCypB) that retained characteristic PPIase activity without host bacterium toxicity. This study presents an alternative expression strategy for proteins toxic to prokaryotes, such as SgCypB. ONE-SENTENCE SUMMARY: The recombinant cyclophilin B protein of Sporothrix globosa was expressed successfully by retaining extracellular domain with peptidyl-prolyl cis-trans isomerase activity to avoid toxicity to the host bacterium.

Disasters pile up on the rubbing heel: Sporothrix globosa as secondary infection to Mycobacterium chelonae infection.

Mycobacterium chelonae and Sporothrix globosa, both of which are opportunistic pathogens, have been proved to be possible multidrug resistant. However, are all recurring symptoms in chronic infections related to decreasing susceptibility? Here we report a case of sporotrichosis secondary to M. chelonae infection. In addition, we find that the blackish-red spots under the dermoscopic view can be employed as a signal for the early identification and regression of subcutaneous fungal infection.

Anti-Sporothrix Activity of Novel Copper-Itraconazole Complexes.

A series of new metal complexes, [Cu(ITZ)2Cl2] ⋅ 5H2O (1), [Cu(NO3)2(ITZ)2] ⋅ 3H2O ⋅ C4H10O (2) and [Cu(ITZ)2)(PPh3)2]NO3 ⋅ 5H2O (3) were synthesized by a reaction of itraconazole (ITZ) with the respective copper salts under reflux. The metal complexes were characterized by elemental analyses, molar conductivity, 1H and 13C{1H} nuclear magnetic resonance, UV-Vis, infrared and EPR spectroscopies. The antifungal activity of these metal complexes was evaluated against the main sporotrichosis agents: Sporothrix brasiliensis, Sporothrix schenkii, and Sporothrix globosa. All three new compounds inhibited the growth of S. brasiliensis and S. schenckii at lower concentrations than the free azole, with complex 2 able to kill all species at 4 µM and induce more pronounced alterations in fungal cells. Complexes 2 and 3 exhibited higher selectivity and no mutagenic effect at the concentration that inhibited fungal growth and affected fungal cells. The strategy of coordinating itraconazole (ITZ) to copper was successful, since the corresponding metal complexes were more effective than the parent drug. Particularly, the promising antifungal activity of the Cu-ITZ complexes makes them potential candidates for the development of an alternative drug to treat mycoses.

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.

In vitro activity of the anthelmintic drug niclosamide against Sporothrix spp. strains with distinct genetic and antifungal susceptibility backgrounds.

The drugs available to treat sporotrichosis, an important yet neglected fungal infection, are limited. Some Sporothrix spp. strains present reduced susceptibility to these antifungals. Furthermore, some patients may not be indicated to use these drugs, while others may not respond to the therapy. The anthelmintic drug niclosamide is fungicidal against the Sporothrix brasiliensis type strain. This study aimed to evaluate whether niclosamide also has antifungal activity against Sporothrix globosa, Sporothrix schenckii and other S. brasiliensis strains with distinct genotypes and antifungal susceptibility status. Minimal inhibitory and fungicidal concentrations (MIC and MFC, respectively) were determined using the microdilution method according to the CLSI protocol. The checkerboard method was employed to evaluate niclosamide synergism with drugs used in sporotrichosis treatment. Metabolic activity of the strains under niclosamide treatment was evaluated using the resazurin dye. Niclosamide was active against all S. brasiliensis strains (n = 17), but it was ineffective (MIC > 20 µM) for some strains (n = 4) of other pathogenic Sporothrix species. Niclosamide MIC values for Sporothrix spp. were similar for mycelial and yeast-like forms of the strains (P = 0.6604). Niclosamide was fungicidal (MFC/MIC ratio ≤ 2) for most strains studied (89%). Niclosamide activity against S. brasiliensis is independent of the fungal genotype or non-wild-type phenotypes for amphotericin B, itraconazole, or terbinafine. These antifungal drugs presented indifferent interactions with niclosamide. Niclosamide has demonstrated potential for repurposing as a treatment for sporotrichosis, particularly in S. brasiliensis cases, instigating in vivo studies to validate the in vitro findings.

Bioisosteric modification on benzylidene-carbonyl compounds improved the drug-likeness and maintained the antifungal activity against Sporothrix brasiliensis.

Considering the emergence of antifungal resistance on Sporothrix brasiliensis, we aimed to assess new benzylidene-carbonyl compounds against feline-borne S. brasiliensis isolates. The compounds were designed as bioisosteres from previously reported benzylidene-ketones generating the p-coumaric (1), cinnamic (2), p-methoxycinnamic (3) and caffeic acid (4) analogues. The corresponding compounds were tested against feline isolates of S. brasiliensis with sensitivity (n = 4) and resistance (n = 5) to itraconazole (ITZ), following the M38-A2 protocol (CLSI, Reference method for broth dilution antifungal susceptibility testing of filamentous fungi M38-A2 Guideline, 2008). Eleven analogues showed activity against all fungal strains with minimum inhibitory concentrations (MIC) ≤1 mg/ml (1a-d, 2e, 3b, 3e, 4, 4a and 5e) and fungicidal concentrations (MFC) ≤1 mg/ml (1b, 1d, 3e and 4a), whereas 3 was the less active with both MIC and MFC values above 1 mg/ml. Compound 3e (4-methoxy-N-butylcinnamamide) was the most potent (MICrange 0.08-0.16 mg/ml; MFCrange 0.32-0.64 mg/ml) from the set, suggesting a different role of the substituents in ester and amide derivatives. The designed compounds proved to be important prototypes with improved drug-likeness to achieve compounds with higher activity against ITZ-resistant S. brasiliensis.

Antifungal Activity of a Neodymium-Doped Yttrium Aluminum Garnet 1,064-Nanometer Laser against Sporothrix globosa by Inducing Apoptosis and Pyroptosis via the NLRP3/Caspase-1 Signaling Pathway: In Vitro and In Vivo Study.

Sporotrichosis is a deep fungal infection caused by Sporothrix species. Currently, itraconazole is the main treatment, but fungal resistance, adverse effects, and drug interactions remain major concerns, especially in patients with immune dysfunction. Therefore, an alternative treatment is greatly in demand. This animal study aimed to investigate the inhibitory effect of neodymium-doped yttrium aluminum garnet (Nd:YAG) 1,064-nm laser treatment on Sporothrix globosa and to explore whether it happens through regulation of the Nod-like receptor thermoprotein domain-related protein 3 (NLRP3)/caspase-1 pyroptosis and apoptosis pathway. After laser irradiation, a series of studies, including assays of viability (using the cell counting kit-8 [CCK-8]), morphological structure changes, reactive oxygen species (ROS) accumulation, mitochondrial membrane potential, oxidative stress, cell cycle progression, and metacaspase activation, were conducted to estimate the effect of Nd:YAG 1,064-nm laser treatment on Sporothrix globosa cell apoptosis in vitro. For in vivo studies, mice were infected with S. globosa and then treated with laser or itraconazole, and their footpad skin lesions and the changes in the histology of tissue samples were compared. In addition, changes in the levels of NLRP3, caspase-1, and caspase-3 were assessed by immunohistochemistry, while the levels of interleukin 17 (IL-17), interferon gamma (IFN-γ), and transforming growth factor ß1 (TGF-ß1) in peripheral blood were tested by enzyme-linked immunosorbent assay (ELISA). The in vitro growth of S. globosa was inhibited and apoptosis was observed after laser treatment. According to the in vivo studies, the efficacy of the laser treatment was similar to that of itraconazole. Moreover, the NLRP3/caspase-1 pyroptosis pathway was activated, with a Th1/Th17 cell response, and the expression of caspase-3 was also upregulated. Nd:YAG 1,064-nm laser treatment can effectively inhibit the growth of S. globosa by activating fungal apoptosis and pyroptosis through the NLRP3/caspase-1 pathway. Therefore, Nd:YAG 1,064-nm laser irradiation is an alternative for sporotrichosis therapy. IMPORTANCE Nd:YAG 1,064-nm laser irradiation is a useful alternative for the treatment of sporotrichosis, especially in patients with liver dysfunction, pregnant women, and children, for whom the administration of antifungal drugs is not suitable. It may improve the overall treatment effect by shortening the duration of antifungal treatment and reducing tissue inflammation.

The spread of cat-transmitted sporotrichosis due to Sporothrix brasiliensis in Brazil towards the Northeast region.

BACKGROUND: Sporotrichosis is a worldwide subcutaneous mycosis caused by Sporothrix spp. In the past, this infection was associated with armadillo hunting, horticulturists, miners, and gardeners, being considered an implantation mycosis acquired by plant debris injury. Nevertheless, since the late nineties, it has been considered a zoonotic disease in Brazil. Here we report a case series of 121 patients with cat-transmitted sporotrichosis seen in Northeast Brazil. METHODOLOGY/PRINCIPAL FINDINGS: Patient's demographic, clinical data, and length of treatment were recorded. In addition, a mycological examination and further PCR confirmation of species identification were performed. One hundred and twenty two patients were diagnosed with subcutaneous sporotrichosis from October 2016 to December 2019, while PCR revealed that 71 of them were due to S. brasiliensis. The majority of the individuals were female (n = 86; 70.5%). Patient's age ranged from 5 to 87 years old. The clinical forms found were lymphocutaneous (58.2%) and fixed cutaneous (39.4%). Interestingly, 115 patients reported previous contact with cats diagnosed with sporotrichosis. Patients were successfully treated with itraconazole and potassium iodide. CONCLUSIONS/SIGNIFICANCE: Our study adds important contributions for the investigation of the spread of cat-transmitted subcutaneous sporotrichosis in Brazil, specifically towards the Northeast region of a continental-size country. It will also help clinicians to be aware of the existence and importance to accurately diagnose sporotrichosis and treat patients with this infectious disease in the lowest income region of Brazil.

Clinical and epidemiological aspects of feline sporotrichosis caused by Sporothrix brasiliensis and in vitro antifungal susceptibility.

Sporotrichosis is a subcutaneous mycosis resulting from the traumatic implantation of pathogenic Sporothrix species. In Brazil, zoonotic transmission plays an important role in the epidemiology of the disease, involving especially cats. The objective of this study was to isolate Sporothrix spp. from cats with signs of sporotrichosis, determining the causative species, clinical and epidemiological aspects, and the in vitro susceptibility profile of the isolates against antifungal drugs. From September 2017 to February 2019, 245 samples of lesions were collected from symptomatic cats in São José do Rio Preto, Brazil. Identification of the isolates was performed by morphophysiological parameters and species-specific polymerase chain reaction. The susceptibility profile of the isolates was determined for five drugs (amphotericin B, itraconazole, ketoconazole, potassium iodide and terbinafine), using the broth microdilution method. Clinical and epidemiological aspects were analyzed based on data contained on investigation forms filled by the veterinarians at moment of collection. Sporothrix spp. were isolated in 189 (77.2%) of the samples. Phenotypic and molecular analyses revealed S. brasiliensis as the only causative agent. In vitro susceptibility testing showed lower MIC values for terbinafine (MIC = 0.03-2 µg/ml), ketoconazole (MIC = 0.03-2 µg/ml), and itraconazole (MIC = 0.03-4 µg/ml). Most of the animals were male (73.5%), adults (96.3%), stray (53.5%), and uncastrated (69.8%). Our results show the expansion of the S. brasiliensis epidemic to an area nearly 840 km apart from the epicenter of the long-lasting outbreak of cat-transmitted sporotrichosis in Rio de Janeiro.

Diphenyl diselenide alone and in combination with itraconazole against Sporothrix schenckii s.str. and Sporothrix globosa.

We evaluated the in vitro susceptibility of Sporothrix schenckii s.str. and Sporothrix globosa to diphenyl diselenide (PhSe)2 alone and in association with itraconazole (ITZ). Eight clinical isolates were tested in microdilution and checkerboard assays. (PhSe)2 alone inhibited all isolates in concentration ≤ 8 µg/mL and was effective in killing one S. schenckii isolate. Inhibitory and fungicidal beneficial effects in its interaction with ITZ were shown against 87.5% (7/8) and 50% (4/8) of the isolates tested, respectively. Our study demonstrates the in vitro antifungal activity of (PhSe)2 against two pathogenic Sporothrix species, suggesting studies of in vivo applications are warranted.

Antifungal promising agents of zinc(II) and copper(II) derivatives based on azole drug.

A series of new metal complexes, [Zn(KTZ)2(Ac)2]·H2O (1), [Zn(KTZ)2Cl2]·0.4CH3OH (2), [Zn(KTZ)2(H2O)(NO3)](NO3) (3), [Cu(KTZ)2(Ac)2]·H2O (4), [Cu(KTZ)2Cl2]·3.2H2O (5), [Cu(KTZ)2(H2O)(NO3)](NO3)·H2O (6), were synthesized by a reaction of ketoconazole (KTZ) with their respective zinc or copper salts under mild conditions. Similarly, six corresponding metal-CTZ (clotrimazole) complexes [Zn(CTZ)2(Ac)2]·4H2O (7), [Zn(CTZ)2Cl2] (8), [Zn(CTZ)2(H2O)(NO3)](NO3)·4H2O (9), [Cu(CTZ)2(Ac)2]·H2O (10), [Cu(CTZ)2Cl2]·2H2O (11), [Cu(CTZ)2(H2O)(NO3)](NO3)·2H2O (12), were obtained. These metal complexes were characterized by elemental analyses, molar conductivity, 1H and 13C{1H} nuclear magnetic resonance, UV/Vis, and infrared spectroscopies. Further, the crystal structure for complexes 7 and 10 was determined by single-crystal X-ray diffraction. The antifungal activity of these metal complexes was evaluated against three fungal species of medical relevance: Candida albicans, Cryptococcus neoformans, and Sporothrix brasiliensis. Complexes 1 and 3 exhibited the greatest antifungal activity with a broad spectrum of action at low concentrations and high selectivity. Some morphological changes induced by these metal complexes in S. brasiliensis cells included yeast-hyphae conversion, an increase in cell size and cell wall damage. The strategy of coordination of clinic drugs (KTZ and CTZ) to zinc and copper was successful, since the corresponding metal complexes were more effective than the parent drug. Particularly, the promising antifungal activities displayed by Zn-KTZ complexes make them potential candidates for the development of an alternative drug to treat mycoses.

Susceptibility and resistance of Sporothrix brasiliensis to branded and compounded itraconazole formulations.

Itraconazole is the first drug of choice for the treatment of sporotrichosis and it is available at different concentrations for veterinary patients. However, therapeutic failure has been reported, limiting clinical treatment. This study evaluated the in vitro efficacy of brand-name and compounded itraconazole formulations against Sporothrix brasiliensis and estimated the itraconazole content in each tested formulation. Oral capsules were acquired from two brand-name products for human (H-IND) and veterinary (V-IND) uses, and three from compounding pharmacies in Pelotas, RS, for human (H-COMP1/H-COMP2) and veterinary (V-COMP) uses. Capsule purity was analyzed by liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). Antifungal activity was determined against 29 Sporothrix brasiliensis by the M38-A2 guideline of CLSI. H-IND/H-COMP1/H-COMP2 had high efficacy against S. brasiliensis (approximately 70% of total isolated susceptible), V-COMP showed moderate efficacy (51.7%), and V-IND was the least effective formulation (37.9%). Thirty-four percent of the total isolates were resistant to all formulations. Furthermore, itraconazole content did not match the concentration indicated by the manufacturers, ranging from 387.70 to 7.81 µg/mg (H-COMP2 > V-COMP > H-IND > H-COMP1 > V-IND). Therefore, it is possible that the formulations showed different in vitro efficacy due to the difference in their itraconazole contents. Given the emergence of antifungal resistance for all formulations, the choice product to be used must follow susceptibility testing. Stringent quality control measures are recommended for product manufactures to assure drug content uniformity.

In vivo protection of the marjoram (Origanum majorana Linn.) essential oil in the cutaneous sporotrichosis by Sporothrix brasiliensis.

Thirty Wistar rats subcutaneously infected by an itraconazole-resistant Sporothrix brasiliensis received the oral daily treatment (n = 10, each) of control (CTL, saline solution), itraconazole (ITZ, 10 mg/kg) and marjoram essential oil (MRJ, 80 mg/kg) for 30 days. Weekly, the clinical evaluation and euthanasia for histopathology and fungal burden were performed. Only animals from MRJ evolved to the remission of the cutaneous lesion with a mild to absent presence of yeasts in footpad, besides decreased the fungal burden in the systemic organs compared to CTL and ITZ (p < 0.05), preventing the fungal spread, mainly in the liver and spleen. The antifungal activity may have been attributed to the majority composition of terpinen-4-ol (34.09%), γ-terpinene (14.28%) and α-terpinene (9.6%), which the mode of action was at the level of ergosterol complexation. These findings highlighted the antifungal and the systemic protective effects of MRJ, supporting the promising use in the treatment of cutaneous sporotrichosis.

Promising application of the SsCBF ELISA test to monitor the therapeutic response of feline sporotrichosis caused by Sporothrix brasiliensis from Brazilian epidemics.

Sporotrichosis zoonotic transmission by cats has obtained hyperendemic magnitude in Rio de Janeiro, Brazil. Atypical cases, relapses, and reinfections as well as reduced diagnostic sensitivity of conventional methods have been reported. Previously, the anti-SsCBF enzyme-linked immunosorbent assay (ELISA) test was shown to be useful as a diagnostic tool for human sporotrichosis. Effective diagnosis and treatment are critical to interrupt the chain of transmission of this major pathogen in Brazilian Public Health. To evaluate its applicability for feline sporotrichosis diagnosis and/or therapeutic follow-up, 15 domestic cats from Rio de Janeiro were clinically and laboratory monitored by cytopathology, culture, Sporothrix genotyping, and anti-SsCBF IgG levels. Subsequently, animals were divided into satisfactory and non-satisfactory therapeutic responders. Averages of antibody serum levels obtained for diagnosis (first consultation) compared with the levels found after follow-up (last consultation) were significantly different in both groups (p = 0.0002 and p = 0.038, respectively). We conclude that the SsCBF ELISA test can predict feline sporotrichosis therapeutic responses even for animals with distinct clinical evolutions.

Phenotypic and molecular characterisation of Sporothrix globosa of diverse origin from India.

Sporotrichosis is one of the neglected tropical diseases causing subcutaneous chronic granulomatous lesion by thermally dimorphic fungi belonging to Sporothrix species. Sporothrix brasiliensis, Sporothrix mexicana and Sporothrix globosa are the common pathogenic species. In Asian countries, S. globosa constitutes nearly 99.3% of all Sporothrix species. We studied 63 cases of sporotrichosis of geographically diverse origin from India and Sporothrix isolates were characterised for its growth in different media, temperatures, ability to assimilate sugars and antifungal susceptibility profile. Molecular characterization was performed by sequencing of the calmodulin (CAL), beta tubulin (BT) and translational elongation factor 1-alpha (TEF-1α) and typing by fluorescent amplified fragment length polymorphism (FAFLP). In patients who presented with fixed (49.2%), lymphocutaneous lesions (23.8%), in 26.9% the details were not known, none had systemic dissemination. All the isolates tested were Sporothrix globosa and that could grow up to 35 °C and unable to grow at and beyond 37 °C. The assimilation of sucrose, ribitol and raffinose helps in identifying S. globosa. Sequences of CAL or BT or TEF-1α can differentiate S. globosa from other species in the complex. FAFLP results exhibited low genetic diversity. No correlation was noted between genotypes and clinical presentation, or geographic distribution. Itraconazole, terbinafine and posaconazole showed good in vitro antifungal activity against S. globosa whereas fluconazole and micafungin had no activity. S. globosa of Indian origin is relatively less pathogenic than other pathogenic Sporothrix species as it does not cause systemic dissemination and in the diagnostic laboratory, incubation of the cultures below 37 °C is essential for effective isolation.

Antifungal resistance on Sporothrix species: an overview.

INTRODUCTION: The treatment of human and animal sporotrichosis is often performed with antifungal agents; however, the emergence of antifungal-resistant strains of Sporothrix species has been reported. We aimed to discuss the ability of Sporothrix species in developing resistance to the conventional antifungals and mechanisms for this. METHODOLOGY: Published data on databases (PubMed, Science Direct, Google Scholar) were investigated using a combination of keywords from 2008 to 2019 by the StArt tool. RESULTS: The minimal inhibitory concentrations values based on the Clinical and Laboratory Standards Institute (CLSI) from eight references were classified according to the epidemiological cutoff values in wild-type or non-wild-type strains. In this way, non-wild-type S. schenckii and, mainly, S. brasiliensis isolates were recognized on itraconazole, amphotericin B, terbinafine, and voriconazole, which are strains that deserve more attention toward antifungal control, with a probable risk of mutation to antifungal resistance. Among the few reviewed studied on antifungal resistance, the melanin production capacity (DHN-melanin, L-DOPA melanin, and pyomelanin), the low genetic diversity due to the abnormal number of chromosomes, and the mutation in cytochrome P450 are some of the factors for developing resistance mechanism. CONCLUSIONS: The emergence of Sporothrix species with in vitro antifungal resistance was evidenced and the possible mechanisms for resistance development may be due to the melanin production capacity, genetic diversity and mutations in cytochrome P450. Further studies should be carried out targeting gene expression for the development of antifungal resistance on Sporothrix species in order to prospect new therapeutic targets for human and veterinary use.

Potential use of Nikkomycin Z as an anti- Sporothrix spp. drug.

Sporotrichosis, the most common subcutaneous mycosis in several countries, is caused by the dimorphic fungus, Sporothrix spp. Given some limitations in the treatment of this disease, and the high potential of nikkomycin Z (NikZ) as an antifungal against dimorphic fungi, this study aimed to evaluate the in vitro susceptibility of Sporothrix spp. to NikZ alone and with the drug of choice, itraconazole (ITZ). Seventeen clinical isolates of three Sporothrix spp. species (10 S. brasiliensis, six S. schenckii sensu stricto and one S. globosa) were tested in microdilution and checkerboard assays. Minimal inhibitory concentration (MIC), minimal fungicidal concentration (MFC), fractional inhibitory and fungicidal concentration indexes (FICi and FFCi) were analyzed. MIC of NikZ alone could be determined against S. globosa (12.5 µg/ml) and against 67% (4/6) and 30% (3/10) of the S. schenckii sensu stricto and S. brasiliensis isolates, respectively (≤ 400 µg/ml). Synergism with ITZ was showed against almost all the isolates tested (94%; 16/17), including reversing resistance to ITZ alone in some isolates. Our study shows the potential of NikZ in sporotrichosis treatment. Further studies in experimental models are needed to understand the possible future application of this drug as an alternative therapy or as an adjuvant in sporotrichosis treatment. LAY ABSTRACT: Sporotrichosis is a subcutaneous and lymphatic infection, caused by fungi of Sporothrix spp. Our study shows the potential of NikZ to inhibiting Sporothrix species in vitro. Further studies are needed to understand the future application of this drug to sporotrichosis treatment.

Anti-Sporothrix activity of ibuprofen combined with antifungal.

The in vitro activity of ibuprofen, a nonsteroidal anti-inflammatory drug, was evaluated against Sporothrix brasiliensis and S. schenckii, either alone or in combination with amphotericin B, itraconazole, or terbinafine. The inhibitory activity of ibuprofen as a single agent was determined according to minimum inhibitory concentration (MIC) values, while the effect of ibuprofen combined with amphotericin B, itraconazole, or terbinafine was estimated by microdilution checkerboard methodology. The ultrastructural alterations of S. schenckii after exposure to the combination of ibuprofen and amphotericin B were evaluated by scanning electron microscopy (SEM) and flow cytometry analysis. As a single agent, ibuprofen inhibited Sporothrix growth with a MIC median of 256 µg/mL, while the MIC medians of ibuprofen in combination with antifungals were 16 µg/mL and 128 µg/mL. The MIC values of amphotericin B, itraconazole, and terbinafine were reduced when isolates were co-incubated with ibuprofen, mainly the polyene. The major alteration after treatment with the ibuprofen/amphotericin B combination was the increase in the presence of filamentous forms and high membrane damage with loss of plasma membrane integrity. In summary, we demonstrated that ibuprofen increases the in vitro activity of antifungals, mainly amphotericin B, against S. brasiliensis and S. schenckii. Future in vivo studies exploring combination therapy with ibuprofen and antifungals in animal models are needed to confirm its efficacy.