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1.
Cell ; 161(2): 291-306, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25860611

RESUMO

Cholesterol is dynamically transported among organelles, which is essential for multiple cellular functions. However, the mechanism underlying intracellular cholesterol transport has remained largely unknown. We established an amphotericin B-based assay enabling a genome-wide shRNA screen for delayed LDL-cholesterol transport and identified 341 hits with particular enrichment of peroxisome genes, suggesting a previously unappreciated pathway for cholesterol transport. We show dynamic membrane contacts between peroxisome and lysosome, which are mediated by lysosomal Synaptotagmin VII binding to the lipid PI(4,5)P2 on peroxisomal membrane. LDL-cholesterol enhances such contacts, and cholesterol is transported from lysosome to peroxisome. Disruption of critical peroxisome genes leads to cholesterol accumulation in lysosome. Together, these findings reveal an unexpected role of peroxisome in intracellular cholesterol transport. We further demonstrate massive cholesterol accumulation in human patient cells and mouse model of peroxisomal disorders, suggesting a contribution of abnormal cholesterol accumulation to these diseases.


Assuntos
Colesterol/metabolismo , Lisossomos/metabolismo , Peroxissomos/metabolismo , RNA Interferente Pequeno/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adrenoleucodistrofia/metabolismo , Anfotericina B/farmacologia , Animais , Transporte Biológico , Estudo de Associação Genômica Ampla , Humanos , Camundongos , Transtornos Peroxissômicos/metabolismo , Transtornos Peroxissômicos/patologia , Fosfatidilinositol 4,5-Difosfato/metabolismo , Sinaptotagminas/metabolismo , Peixe-Zebra
2.
Nature ; 623(7989): 1079-1085, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938782

RESUMO

Decades of previous efforts to develop renal-sparing polyene antifungals were misguided by the classic membrane permeabilization model1. Recently, the clinically vital but also highly renal-toxic small-molecule natural product amphotericin B was instead found to kill fungi primarily by forming extramembraneous sponge-like aggregates that extract ergosterol from lipid bilayers2-6. Here we show that rapid and selective extraction of fungal ergosterol can yield potent and renal-sparing polyene antifungals. Cholesterol extraction was found to drive the toxicity of amphotericin B to human renal cells. Our examination of high-resolution structures of amphotericin B sponges in sterol-free and sterol-bound states guided us to a promising structural derivative that does not bind cholesterol and is thus renal sparing. This derivative was also less potent because it extracts ergosterol more slowly. Selective acceleration of ergosterol extraction with a second structural modification yielded a new polyene, AM-2-19, that is renal sparing in mice and primary human renal cells, potent against hundreds of pathogenic fungal strains, resistance evasive following serial passage in vitro and highly efficacious in animal models of invasive fungal infections. Thus, rational tuning of the dynamics of interactions between small molecules may lead to better treatments for fungal infections that still kill millions of people annually7,8 and potentially other resistance-evasive antimicrobials, including those that have recently been shown to operate through supramolecular structures that target specific lipids9.


Assuntos
Antifúngicos , Rim , Polienos , Esteróis , Animais , Humanos , Camundongos , Anfotericina B/análogos & derivados , Anfotericina B/química , Anfotericina B/toxicidade , Antifúngicos/química , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Células Cultivadas , Colesterol/química , Colesterol/metabolismo , Farmacorresistência Fúngica , Ergosterol/química , Ergosterol/metabolismo , Rim/efeitos dos fármacos , Cinética , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico , Micoses/microbiologia , Polienos/química , Polienos/metabolismo , Polienos/farmacologia , Inoculações Seriadas , Esteróis/química , Esteróis/metabolismo , Fatores de Tempo
3.
Annu Rev Microbiol ; 77: 583-602, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37406342

RESUMO

Candida auris is a multidrug-resistant fungal pathogen that presents a serious threat to global human health. Since the first reported case in 2009 in Japan, C. auris infections have been reported in more than 40 countries, with mortality rates between 30% and 60%. In addition, C. auris has the potential to cause outbreaks in health care settings, especially in nursing homes for elderly patients, owing to its efficient transmission via skin-to-skin contact. Most importantly, C. auris is the first fungal pathogen to show pronounced and sometimes untreatable clinical drug resistance to all known antifungal classes, including azoles, amphotericin B, and echinocandins. In this review, we explore the causes of the rapid spread of C. auris. We also highlight its genome organization and drug resistance mechanisms and propose future research directions that should be undertaken to curb the spread of this multidrug-resistant pathogen.


Assuntos
Candida auris , Candida , Humanos , Idoso , Candida/genética , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Equinocandinas , Anfotericina B
4.
N Engl J Med ; 386(12): 1109-1120, 2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35320642

RESUMO

BACKGROUND: Cryptococcal meningitis is a leading cause of human immunodeficiency virus (HIV)-related death in sub-Saharan Africa. Whether a treatment regimen that includes a single high dose of liposomal amphotericin B would be efficacious is not known. METHODS: In this phase 3 randomized, controlled, noninferiority trial conducted in five African countries, we assigned HIV-positive adults with cryptococcal meningitis in a 1:1 ratio to receive either a single high dose of liposomal amphotericin B (10 mg per kilogram of body weight) on day 1 plus 14 days of flucytosine (100 mg per kilogram per day) and fluconazole (1200 mg per day) or the current World Health Organization-recommended treatment, which includes amphotericin B deoxycholate (1 mg per kilogram per day) plus flucytosine (100 mg per kilogram per day) for 7 days, followed by fluconazole (1200 mg per day) for 7 days (control). The primary end point was death from any cause at 10 weeks; the trial was powered to show noninferiority at a 10-percentage-point margin. RESULTS: A total of 844 participants underwent randomization; 814 were included in the intention-to-treat population. At 10 weeks, deaths were reported in 101 participants (24.8%; 95% confidence interval [CI], 20.7 to 29.3) in the liposomal amphotericin B group and 117 (28.7%; 95% CI, 24.4 to 33.4) in the control group (difference, -3.9 percentage points); the upper boundary of the one-sided 95% confidence interval was 1.2 percentage points (within the noninferiority margin; P<0.001 for noninferiority). Fungal clearance from cerebrospinal fluid was -0.40 log10 colony-forming units (CFU) per milliliter per day in the liposomal amphotericin B group and -0.42 log10 CFU per milliliter per day in the control group. Fewer participants had grade 3 or 4 adverse events in the liposomal amphotericin B group than in the control group (50.0% vs. 62.3%). CONCLUSIONS: Single-dose liposomal amphotericin B combined with flucytosine and fluconazole was noninferior to the WHO-recommended treatment for HIV-associated cryptococcal meningitis and was associated with fewer adverse events. (Funded by the European and Developing Countries Clinical Trials Partnership and others; Ambition ISRCTN number, ISRCTN72509687.).


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Fluconazol/administração & dosagem , Flucitosina/administração & dosagem , Meningite Criptocócica/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Administração Oral , África Subsaariana , Anfotericina B/efeitos adversos , Antifúngicos/efeitos adversos , Esquema de Medicação , Quimioterapia Combinada , Fluconazol/efeitos adversos , Flucitosina/efeitos adversos , Infecções por HIV/complicações , Meningite Criptocócica/mortalidade
5.
Nature ; 567(7748): 405-408, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30867598

RESUMO

Loss-of-function mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) compromise epithelial HCO3- and Cl- secretion, reduce airway surface liquid pH, and impair respiratory host defences in people with cystic fibrosis1-3. Here we report that apical addition of amphotericin B, a small molecule that forms unselective ion channels, restored HCO3- secretion and increased airway surface liquid pH in cultured airway epithelia from people with cystic fibrosis. These effects required the basolateral Na+, K+-ATPase, indicating that apical amphotericin B channels functionally interfaced with this driver of anion secretion. Amphotericin B also restored airway surface liquid pH, viscosity, and antibacterial activity in primary cultures of airway epithelia from people with cystic fibrosis caused by different mutations, including ones that do not yield CFTR, and increased airway surface liquid pH in CFTR-null pigs in vivo. Thus, unselective small-molecule ion channels can restore host defences in cystic fibrosis airway epithelia via a mechanism that is independent of CFTR and is therefore independent of genotype.


Assuntos
Fibrose Cística/metabolismo , Epitélio/metabolismo , Canais Iônicos/metabolismo , Mucosa Respiratória/metabolismo , Sistema Respiratório/metabolismo , Anfotericina B/farmacologia , Animais , Bicarbonatos/metabolismo , Células Cultivadas , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/deficiência , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Epitélio/efeitos dos fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Mucosa Respiratória/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Suínos
6.
Clin Microbiol Rev ; 36(4): e0015622, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38014977

RESUMO

Cryptococcal meningitis is a leading cause of morbidity and mortality globally, especially in people with advanced HIV disease. Cryptococcal meningitis is responsible for nearly 20% of all deaths related to advanced HIV disease, with the burden of disease predominantly experienced by people in resource-limited countries. Major advancements in diagnostics have introduced low-cost, easy-to-use antigen tests with remarkably high sensitivity and specificity. These tests have led to improved diagnostic accuracy and are essential for screening campaigns to reduce the burden of cryptococcosis. In the last 5 years, several high-quality, multisite clinical trials have led to innovations in therapeutics that have allowed for simplified regimens, which are better tolerated and result in less intensive monitoring and management of medication adverse effects. One trial found that a shorter, 7-day course of deoxycholate amphotericin B is as effective as the longer 14-day course and that flucytosine is an essential partner drug for reducing mortality in the acute phase of disease. Single-dose liposomal amphotericin B has also been found to be as effective as a 7-day course of deoxycholate amphotericin B. These findings have allowed for simpler and safer treatment regimens that also reduce the burden on the healthcare system. This review provides a detailed discussion of the latest evidence guiding the clinical management and special circumstances that make cryptococcal meningitis uniquely difficult to treat.


Assuntos
Infecções por HIV , Meningite Criptocócica , Adulto , Humanos , Anfotericina B/uso terapêutico , Ácido Desoxicólico/uso terapêutico , Fluconazol/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Meningite Criptocócica/diagnóstico , Meningite Criptocócica/tratamento farmacológico , Ensaios Clínicos como Assunto
7.
J Infect Dis ; 229(2): 599-607, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38109276

RESUMO

BACKGROUND: Candida auris isolates exhibit elevated amphotericin B (AMB) minimum inhibitory concentrations (MICs). As liposomal AMB (L-AMB) can be safely administered at high doses, we explored L-AMB pharmacodynamics against C. auris isolates in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) dilution model. METHODS: Four C. auris isolates with Clinical and Laboratory Standards Institute (CLSI) AMB MICs = 0.5-2 mg/L were tested in an in vitro PK/PD model simulating L-AMB pharmacokinetics. The in vitro model was validated using a Candida albicans isolate tested in animals. The peak concentration (Cmax)/MIC versus log10 colony-forming units (CFU)/mL reduction from the initial inoculum was analyzed with the sigmoidal model with variable slope (Emax model). Monte Carlo analysis was performed for the standard (3 mg/kg) and higher (5 mg/kg) L-AMB doses. RESULTS: The in vitro PK/PD relationship Cmax/MIC versus log10 CFU/mL reduction followed a sigmoidal pattern (R2 = 0.91 for C. albicans, R2 = 0.86 for C. auris). The Cmax/MIC associated with stasis was 2.1 for C. albicans and 9 for C. auris. The probability of target attainment was >95% with 3 mg/kg for wild-type C. albicans isolates with MIC ≤2 mg/L and C. auris isolates with MIC ≤1 mg/L whereas 5 mg/kg L-AMB is needed for C. auris isolates with MIC 2 mg/L. CONCLUSIONS: L-AMB was 4-fold less active against C. auris than C. albicans. Candida auris isolates with CLSI MIC 2 mg/L would require a higher L-AMB dose.


Assuntos
Anfotericina B , Antifúngicos , Animais , Anfotericina B/farmacologia , Antifúngicos/farmacocinética , Candida auris , Candida , Candida albicans , Testes de Sensibilidade Microbiana
8.
Biochemistry ; 63(8): 953-957, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38545902

RESUMO

A major challenge currently facing medicinal chemists is designing agents that can selectively destroy drug resistant fungi and bacteria that have begun to emerge. One factor that has been overlooked by virtually all drug discovery/development approaches is the supramolecular factor, in which aggregated forms of a drug candidate exhibit low selectivity in destroying targeted cells while the corresponding monomers exhibit high selectivity. This Perspective discusses how we were led to the supramolecular factor through fundamental studies with simple model systems, how we reasoned that the selectivity of monomers of the antifungal agent amphotericin B should be much greater than the selectivity of the corresponding aggregates, and how we confirmed this hypothesis using derivatives of amphotericin B. In a broader context, these findings provide a strong rationale for considering the supramolecular factor in the design of new drug candidates and the testing of virtually all of them.


Assuntos
Anfotericina B , Antifúngicos , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Fungos , Desenho de Fármacos , Descoberta de Drogas
9.
Mol Microbiol ; 120(5): 723-739, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37800599

RESUMO

DectiSomes are anti-infective drug-loaded liposomes targeted to pathogenic cells by pathogen receptors including the Dectins. We have previously used C-type lectin (CTL) pathogen receptors Dectin-1, Dectin-2, and DC-SIGN to target DectiSomes to the extracellular oligoglycans surrounding diverse pathogenic fungi and kill them. Dectin-3 (also known as MCL, CLEC4D) is a CTL pathogen receptor whose known cognate ligands are partly distinct from other CTLs. We expressed and purified a truncated Dectin-3 polypeptide (DEC3) comprised of its carbohydrate recognition domain and stalk region. We prepared amphotericin B (AmB)-loaded pegylated liposomes (AmB-LLs) and coated them with this isoform of Dectin-3 (DEC3-AmB-LLs), and we prepared control liposomes coated with bovine serum albumin (BSA-AmB-LLs). DEC3-AmB-LLs bound to the exopolysaccharide matrices of Candida albicans, Rhizopus delemar (formerly known as R. oryzae), and Cryptococcus neoformans from one to several orders of magnitude more strongly than untargeted AmB-LLs or BSA-AmB-LLs. The data from our quantitative fluorescent binding assays were standardized using a CellProfiler program, AreaPipe, that was developed for this purpose. Consistent with enhanced binding, DEC3-AmB-LLs inhibited and/or killed C. albicans and R. delemar more efficiently than control liposomes and significantly reduced the effective dose of AmB. In conclusion, Dectin-3 targeting has the potential to advance our goal of building pan-antifungal DectiSomes.


Assuntos
Antifúngicos , Criptococose , Humanos , Antifúngicos/farmacologia , Lipossomos/química , Lipossomos/farmacologia , Anfotericina B/farmacologia , Anfotericina B/química , Candida albicans
10.
Antimicrob Agents Chemother ; 68(1): e0096823, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38084953

RESUMO

Antifungal susceptibility testing (AST) is crucial in clinical settings to guide appropriate therapy. Nevertheless, discrepancies between treatment response and some results still persist, particularly in detecting resistance to amphotericin B (AMB) in Clavispora (Candida) lusitaniae. This study aimed to assess the susceptibility patterns of 48 recent isolates of C. lusitaniae to 9 antifungal agents and explore the feasibility of using a CLSI reference-based method to identify AMB resistance. Microdilution techniques revealed a wide range of minimal inhibitory concentration (MIC) values for azole antifungals, while echinocandins and AMB exhibited a narrow range of MIC values, with all strains considered wild-type for the tested polyene and echinocandins. However, when agar diffusion (ellipsometry) was employed for AST, certain strains displayed colonies within the inhibition ellipse, indicating potential resistance. Interestingly, these strains did not respond to AMB treatment and were isolated during AMB treatment (breakthrough). Moreover, the evaluation of AMB minimum fungicidal concentrations (MFCs) indicated that only the strains with colonies inside the ellipse had MFC/MIC ratios ≥ 4, suggesting reduced fungicidal activity. In conclusion, this study confirms the effectiveness of ellipsometry with RPMI-1640 2% glucose agar for detecting AMB resistance in C. lusitaniae. Additionally, the proposed approach of culturing "clear" wells in the microdilution method can aid in uncovering resistant strains. The findings highlight the importance of appropriate AST methods to guide effective treatment strategies for deep-seated candidiasis caused by C. lusitaniae. Further collaborative studies are warranted to validate these findings and improve the detection of AMB clinical resistance.


Assuntos
Anfotericina B , Antifúngicos , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Ágar/farmacologia , Equinocandinas/farmacologia , Testes de Sensibilidade Microbiana
11.
Antimicrob Agents Chemother ; 68(5): e0154523, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38557112

RESUMO

Ibrexafungerp (formerly SCY-078) is the first member of the triterpenoid class that prevents the synthesis of the fungal cell wall polymer ß-(1,3)-D-glucan by inhibiting the enzyme glucan synthase. We evaluated the in vivo efficacy of ibrexafungerp against pulmonary mucormycosis using an established murine model. Neutropenic mice were intratracheally infected with either Rhizopus delemar or Mucor circinelloides. Treatment with placebo (diluent control), ibrexafungerp (30 mg/kg, PO BID), liposomal amphotericin B (LAMB 10 mg/kg IV QD), posaconazole (PSC 30 mg/kg PO QD), or a combination of ibrexafungerp plus LAMB or ibrexafungerp plus PSC began 16 h post-infection and continued for 7 days for ibrexafungerp or PSC and through day 4 for LAMB. Ibrexafungerp was as effective as LAMB or PSC in prolonging median survival (range: 15 days to >21 days) and enhancing overall survival (30%-65%) vs placebo (9 days and 0%; P < 0.001) in mice infected with R. delemar. Furthermore, median survival and overall percent survival resulting from the combination of ibrexafungerp plus LAMB were significantly greater compared to all monotherapies (P ≤ 0.03). Similar survival results were observed in mice infected with M. circinelloides. Monotherapies also reduce the lung and brain fungal burden by ~0.5-1.0log10 conidial equivalents (CE)/g of tissue vs placebo in mice infected with R. delemar (P < 0.05), while a combination of ibrexafungerp plus LAMB lowered the fungal burden by ~0.5-1.5log10 CE/g compared to placebo or any of the monotherapy groups (P < 0.03). These results are promising and warrant continued investigation of ibrexafungerp as a novel treatment option against mucormycosis.


Assuntos
Anfotericina B , Antifúngicos , Glicosídeos , Mucormicose , Neutropenia , Triterpenos , Animais , Anfotericina B/uso terapêutico , Anfotericina B/farmacologia , Mucormicose/tratamento farmacológico , Camundongos , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Neutropenia/tratamento farmacológico , Neutropenia/complicações , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Rhizopus/efeitos dos fármacos , Pneumopatias Fúngicas/tratamento farmacológico , Pneumopatias Fúngicas/microbiologia , Mucor/efeitos dos fármacos , Triazóis/uso terapêutico , Triazóis/farmacologia
12.
J Clin Microbiol ; 62(4): e0152823, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38501836

RESUMO

Although the Vitek 2 system is broadly used for antifungal susceptibility testing of Candida spp., its performance against Candida auris has been assessed using limited number of isolates recovered from restricted geographic areas. We therefore compared Vitek 2 system with the reference Clinical and Laboratory Standards Institute (CLSI) broth microdilution method using an international collection of 100 C. auris isolates belonging to different clades. The agreement ±1 twofold dilution between the two methods and the categorical agreement (CA) based on the Centers for Disease Control and Prevention's (CDC's) tentative resistance breakpoints and Vitek 2-specific wild-type upper limit values (WT-ULVs) were determined. The CLSI-Vitek 2 agreement was poor for 5-flucytosine (0%), fluconazole (16%), and amphotericin B (29%), and moderate for voriconazole (61%), micafungin (67%), and caspofungin (81%). Significant interpretation errors were recorded using the CDC breakpoints for amphotericin B (31% CA, 69% major errors; MaEs) and fluconazole (69% CA, 31% very major errors; VmEs), but not for echinocandins (99% CA, 1% MaEs for both micafungin and caspofungin) for which the Vitek 2 allowed correct categorization of echinocandin-resistant FKS1 mutant isolates. Discrepancies were reduced when the Vitek 2 WT-ULV of 16 mg/L for amphotericin B (98% CA, 2% MaEs) and of 4 mg/L for fluconazole (96% CA, 1% MaEs, 3% VmEs) were used. In conclusion, the Vitek 2 system performed well for echinocandin susceptibility testing of C .auris. Resistance to fluconazole was underestimated whereas resistance to amphotericin B was overestimated using the CDC breakpoints of ≥32 and ≥2 mg/L, respectively. Vitek 2 minimun inhibitory concentrations (MICs) >4 mg/L indicated resistance to fluconazole and Vitek 2 MICs ≤16 mg/L indicated non-resistance to amphotericin B.


Assuntos
Anfotericina B , Fluconazol , Humanos , Fluconazol/farmacologia , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candida auris , Micafungina , Caspofungina , Testes de Sensibilidade Microbiana , Equinocandinas/farmacologia
13.
J Antimicrob Chemother ; 79(7): 1547-1554, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38727613

RESUMO

INTRODUCTION: Post-kala-azar dermal leishmaniasis (PKDL) arises as a dermal complication following a visceral leishmaniasis (VL) infection. Current treatment options for PKDL are unsatisfactory, and there is a knowledge gap regarding the distribution of antileishmanial compounds within human skin. The present study investigated the skin distribution of miltefosine in PKDL patients, with the aim to improve the understanding of the pharmacokinetics at the skin target site in PKDL. METHODS: Fifty-two PKDL patients underwent treatment with liposomal amphotericin B (20 mg/kg) plus miltefosine (allometric dosing) for 21 days. Plasma concentrations of miltefosine were measured on study days 8, 15, 22 and 30, while a punch skin biopsy was taken on day 22. A physiologically based pharmacokinetic (PBPK) model was developed to evaluate the distribution of miltefosine into the skin. RESULTS: Following the allometric weight-based dosing regimen, median miltefosine concentrations on day 22 were 43.73 µg/g (IQR: 21.94-60.65 µg/g) in skin and 33.29 µg/mL (IQR: 25.9-42.58 µg/mL) in plasma. The median individual concentration ratio of skin to plasma was 1.19 (IQR: 0.79-1.9). In 87% (45/52) of patients, skin exposure was above the suggested EC90 PK target of 10.6 mg/L associated with in vitro susceptibility. Simulations indicated that the residence time of miltefosine in the skin would be more than 2-fold longer than in plasma, estimated by a mean residence time of 604 versus 266 hours, respectively. CONCLUSION: This study provides the first accurate measurements of miltefosine penetration into the skin, demonstrating substantial exposure and prolonged retention of miltefosine within the skin. These findings support the use of miltefosine in cutaneous manifestations of leishmaniasis. In combination with parasitological and clinical data, these results are critical for the future optimization of combination therapies with miltefosine in the treatment of PKDL.


Assuntos
Anfotericina B , Antiprotozoários , Leishmaniose Cutânea , Leishmaniose Visceral , Fosforilcolina , Pele , Humanos , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacocinética , Fosforilcolina/administração & dosagem , Fosforilcolina/uso terapêutico , Antiprotozoários/farmacocinética , Antiprotozoários/administração & dosagem , Antiprotozoários/uso terapêutico , Masculino , Adulto , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Feminino , Pele/parasitologia , Leishmaniose Visceral/tratamento farmacológico , Pessoa de Meia-Idade , Adulto Jovem , Anfotericina B/farmacocinética , Anfotericina B/uso terapêutico , Anfotericina B/administração & dosagem , Adolescente , Ásia Meridional
14.
J Antimicrob Chemother ; 79(4): 703-711, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38252921

RESUMO

INTRODUCTION: Therapeutic drug monitoring (TDM) is a tool that supports personalized dosing, but its role for liposomal amphotericin B (L-amb) is unclear. This systematic review assessed the evidence for L-amb TDM in children. OBJECTIVES: To evaluate the concentration-efficacy relationship, concentration-toxicity relationship and pharmacokinetic/pharmacodynamic (PK/PD) variability of L-amb in children. METHODS: We systematically reviewed PubMed and Embase databases following PRISMA guidelines. Eligible studies included L-amb PK/PD studies in children aged 0-18 years. Review articles, case series of 600 mg·h/L for nephrotoxicity. L-amb doses of 2.5-10 mg/kg/day were reported to achieve Cmax/MIC > 25 using an MIC of 1 mg/L. CONCLUSIONS: While significant PK variability was observed in children, evidence to support routine L-amb TDM was limited. Further studies on efficacy and toxicity benefits are required before routine TDM of L-amb can be recommended.


Assuntos
Antifúngicos , Candidíase Invasiva , Criança , Animais , Humanos , Recém-Nascido , Antifúngicos/efeitos adversos , Monitoramento de Medicamentos , Anfotericina B/efeitos adversos , Candidíase Invasiva/tratamento farmacológico
15.
PLoS Pathog ; 18(10): e1010858, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36227854

RESUMO

Mucormycosis (previously called zygomycosis) is a serious but rare fungal infection caused by a group of fungi belonging to the order Mucorales. These molds exist throughout the environment and generally do not cause serious problems in humans. Mucormycosis mainly affects individuals who are immunocompromised. The clinical manifestations of mucormycosis are wide-ranging; they include sinusitis (pansinusitis, rhino-orbital, or rhino-cerebral) as well as cutaneous, gastrointestinal, pulmonary, and disseminate infections. Many uncertainties remain regarding how to control these infections despite the recent addition of triazoles to the antifungal arsenal for treating this infection. Currently, lipid formulations of amphotericin B have become the standard treatment for mucormycosis due to their efficiency. Moreover, a growing body of data supports the need for surgical excision of infected and/or necrosed tissue whenever practical. In this mini review, the current status of treatment options for mucormycosis and recent studies of novel therapeutic options will be presented.


Assuntos
Mucormicose , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Desbridamento , Humanos , Lipídeos , Mucormicose/tratamento farmacológico , Triazóis/uso terapêutico
16.
Arch Biochem Biophys ; 753: 109884, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218361

RESUMO

The spread of fungi resistant to conventional drugs has become a threatening problem. In this context, antimicrobial peptides (AMPs) have been considered as one of the main alternatives for controlling fungal infections. Here, we report the antifungal and antibiofilm activity and some clues about peptide RQ18's mechanism of action against Candida and Cryptococcus. This peptide inhibited yeast growth from 2.5 µM and killed all Candida tropicalis cells within 2 h incubation. Moreover, it showed a synergistic effect with antifungal agent the amphotericin b. RQ18 reduced biofilm formation and promoted C. tropicalis mature biofilms eradication. RQ18's mechanism of action involves fungal cell membrane damage, which was confirmed by the results of RQ18 in the presence of free ergosterol in the medium and fluorescence microscopy by Sytox green. No toxic effects were observed in murine macrophage cell lines and Galleria mellonella larvae, suggesting fungal target selectivity. Therefore, peptide RQ18 represents a promising strategy as a dual antifungal and antibiofilm agent that contributes to infection control without damaging mammalian cells.


Assuntos
Anfotericina B , Antifúngicos , Animais , Camundongos , Antifúngicos/farmacologia , Anfotericina B/farmacologia , Peptídeos/farmacologia , Candida tropicalis , Biofilmes , Testes de Sensibilidade Microbiana , Mamíferos
17.
FEMS Yeast Res ; 242024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38760885

RESUMO

Candida albicans is a human colonizer and also an opportunistic yeast occupying different niches that are mostly hypoxic. While hypoxia is the prevalent condition within the host, the machinery that integrates oxygen status to tune the fitness of fungal pathogens remains poorly characterized. Here, we uncovered that Snf5, a subunit of the chromatin remodeling complex SWI/SNF, is required to tolerate antifungal stress particularly under hypoxia. RNA-seq profiling of snf5 mutant exposed to amphotericin B and fluconazole under hypoxic conditions uncovered a signature that is reminiscent of copper (Cu) starvation. We found that under hypoxic and Cu-starved environments, Snf5 is critical for preserving Cu homeostasis and the transcriptional modulation of the Cu regulon. Furthermore, snf5 exhibits elevated levels of reactive oxygen species and an increased sensitivity to oxidative stress principally under hypoxia. Supplementing growth medium with Cu or increasing gene dosage of the Cu transporter CTR1 alleviated snf5 growth defect and attenuated reactive oxygen species levels in response to antifungal challenge. Genetic interaction analysis suggests that Snf5 and the bona fide Cu homeostasis regulator Mac1 function in separate pathways. Together, our data underlined a unique role of SWI/SNF complex as a potent regulator of Cu metabolism and antifungal stress under hypoxia.


Assuntos
Antifúngicos , Candida albicans , Cobre , Regulação Fúngica da Expressão Gênica , Estresse Oxidativo , Cobre/metabolismo , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Candida albicans/metabolismo , Candida albicans/fisiologia , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Montagem e Desmontagem da Cromatina , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Espécies Reativas de Oxigênio/metabolismo , Fluconazol/farmacologia , Anaerobiose , Anfotericina B/farmacologia
18.
Parasite Immunol ; 46(5): e13037, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720446

RESUMO

The treatment for visceral leishmaniasis (VL) causes toxicity in patients, entails high cost and/or leads to the emergence of resistant strains. No human vaccine exists, and diagnosis presents problems related to the sensitivity or specificity of the tests. Here, we tested two phage clones, B1 and D11, which were shown to be protective against Leishmania infantum infection in a murine model as immunotherapeutics to treat mice infected with this parasite species. The phages were used alone or with amphotericin B (AmpB), while other mice received saline, AmpB, a wild-type phage (WTP) or WTP/AmpB. Results showed that the B1/AmpB and D11/AmpB combinations induced polarised Th1-type cellular and humoral responses, which were primed by high levels of parasite-specific IFN-γ, IL-12, TNF-α, nitrite and IgG2a antibodies, which reflected in significant reductions in the parasite load in distinct organs of the animals when analyses were performed 1 and 30 days after the treatments. Reduced organic toxicity was also found in these animals, as compared with the controls. In conclusion, preliminary data suggest the potential of the B1/AmpB and D11/AmpB combinations as immunotherapeutics against L. infantum infection.


Assuntos
Anfotericina B , Anticorpos Antiprotozoários , Imunoterapia , Leishmania infantum , Leishmaniose Visceral , Camundongos Endogâmicos BALB C , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/tratamento farmacológico , Animais , Anfotericina B/uso terapêutico , Anfotericina B/administração & dosagem , Anticorpos Antiprotozoários/sangue , Leishmania infantum/imunologia , Leishmania infantum/efeitos dos fármacos , Camundongos , Imunoterapia/métodos , Feminino , Antiprotozoários/uso terapêutico , Antiprotozoários/administração & dosagem , Imunoglobulina G/sangue , Carga Parasitária , Modelos Animais de Doenças , Técnicas de Visualização da Superfície Celular , Citocinas/metabolismo , Células Th1/imunologia
19.
Eur J Clin Microbiol Infect Dis ; 43(4): 713-721, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38347245

RESUMO

BACKGROUND AND AIM: Patients with end-stage liver disease (ESLD) are susceptible to invasive pulmonary aspergillosis (IPA). This study aimed to investigate the risk factors affecting the occurrence and short-term prognosis of ESLD complicated by IPA. METHODS: This retrospective case-control study included 110 patients with ESLD. Of them, 27 ESLD-IPA received antifungal therapy with amphotericin B (AmB); 27 AmB-free-treated ESLD-IPA patients were enrolled through 1:1 propensity score matching. Fifty-six ESLD patients with other comorbid pulmonary infections were enrolled as controls. The basic features of groups were compared, while the possible risk factors affecting the occurrence and short-term outcomes of IPA were analyzed. RESULTS: Data analysis revealed invasive procedures, glucocorticoid exposure, and broad-spectrum antibiotic use were independent risk factors for IPA. The 54 patients with ESLD-IPA exhibited an overall treatment effectiveness and 28-d mortality rate of 50.00% and 20.37%, respectively, in whom patients treated with AmB-containing showed higher treatment efficacy than patients treated with AmB-free antifungal regimens (66.7% vs. 33.3%, respectively, χ2 = 6.000, P = 0.014). Multivariate logistic regression analysis revealed that the treatment regimen was the only predictor affecting patient outcomes, with AmB-containing regimens were 4.893 times more effective than AmB-free regimens (95% CI, 1.367-17.515; P = 0.015). The only independent predictors affecting the 28-d mortality rate were neutrophil-to-lymphocyte ratio and IPA diagnosis (OR = 1.140 and 10.037, P = 0.046 and 0.025, respectively). CONCLUSIONS: Glucocorticoid exposure, invasive procedures, and broad-spectrum antibiotic exposure increased the risk of IPA in ESLD patients. AmB alone or combined with other antifungals may serve as an economical, safe, and effective treatment option for ESLD-IPA.


Assuntos
Doença Hepática Terminal , Aspergilose Pulmonar Invasiva , Humanos , Antifúngicos , Estudos Retrospectivos , Estudos de Casos e Controles , Glucocorticoides , Anfotericina B/uso terapêutico , Prognóstico , Fatores de Risco , Antibacterianos/uso terapêutico
20.
Eur J Clin Microbiol Infect Dis ; 43(5): 927-936, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38483681

RESUMO

PURPOSE: This study investigates how surfactants affect the in-vitro anti-infective efficacy of micafungin, caspofungin, anidulafungin, and amphotericin B in treating pulmonary mycoses. METHODS: MIC values for antifungal agents were determined against Candida krusei (now Pichia kudriavzevii) ATCC 6258, Candida albicans ATCC 90028, and 18 clinical isolates using the broth microdilution method in RPMI medium, following EUCAST recommendations. MIC assays included testing with and without Curosurf® surfactant at 1 mg/mL for C. krusei ATCC 6258 and all C. krusei isolates. Subsequent Time-kill studies in Sabouraud broth involved testing both C. albicans ATCC 90028 and C. krusei ATCC 6258 strains at concentrations equal their respective MIC values, with and without surfactant, using all four antifungals. CFU/mL were assessed at multiple time points up to 24 h. TKCs with different surfactant concentrations for C. krusei ATCC 6258 and mini-TKCs at various concentrations relative to the MIC of C. krusei isolates and the reference strain were conducted with micafungin, anidulafungin, and caspofungin. RESULTS: MIC results showed that 1 µg/mL surfactant reduced killing of micafungin and anidulafungin against C. krusei, while caspofungin was unaffected. Amphotericin B's MIC decreased by half. TKCs demonstrated significant effects of surfactant on micafungin and anidulafungin against C. krusei, with complete abolition of anidulafungin's activity against C. albicans. CONCLUSION: This in-vitro study highlights the concentration-dependent inhibitory effect of surfactant on antifungal activity against C. krusei and, to some extent, C. albicans, necessitating further clinical validation for invasive lung mycoses treatment.


Assuntos
Antifúngicos , Candida albicans , Candida , Testes de Sensibilidade Microbiana , Surfactantes Pulmonares , Antifúngicos/farmacologia , Humanos , Surfactantes Pulmonares/farmacologia , Candida albicans/efeitos dos fármacos , Candida/efeitos dos fármacos , Micafungina/farmacologia , Candidíase/microbiologia , Candidíase/tratamento farmacológico , Anfotericina B/farmacologia , Equinocandinas/farmacologia , Caspofungina/farmacologia
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