RESUMO
Oxidative stress contributes greatly to doxorubicin (DOX)-induced cardiotoxicity. Down-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) is a key factor in DOX-induced myocardial oxidative injury. Recently, we found that mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1)-dependent k48-linked ubiquitination was responsible for down-regulation of myocardial Nrf2 in DOX-treated mice. Micafungin, an antifungal drug, was identified as a potential MALT1 inhibitor. This study aims to explore whether micafungin can reduce DOX-induced myocardial oxidative injury and if its anti-oxidative effect involves a suppression of MALT1-dependent k48-linked ubiquitination of Nrf2. To establish the cardiotoxicity models in vivo and in vitro, mice were treated with a single dose of DOX (15 mg/kg, i.p.) and cardiomyocytes were incubated with DOX (1 µM) for 24 h, respectively. Using mouse model of DOX-induced cardiotoxicity, micafungin (10 or 20 mg/kg) was shown to improve cardiac function, concomitant with suppression of oxidative stress, mitochondrial dysfunction, and cell death in a dose-dependent manner. Similar protective roles of micafungin (1 or 5 µM) were observed in DOX-treated cardiomyocytes. Mechanistically, micafungin weakened the interaction between MALT1 and Nrf2, decreased the k48-linked ubiquitination of Nrf2 while elevated the protein levels of Nrf2 in both DOX-treated mice and cardiomyocytes. Furthermore, MALT1 overexpression counteracted the cardioprotective effects of micafungin. In conclusion, micafungin reduces DOX-induced myocardial oxidative injury via suppression of MALT1, which decreases the k48-linked ubiquitination of Nrf2 and elevates Nrf2 protein levels. Thus, micafungin may be repurposed for treating DOX-induced cardiotoxicity.
Assuntos
Doxorrubicina , Micafungina , Camundongos Endogâmicos C57BL , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Ubiquitinação , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Doxorrubicina/toxicidade , Ubiquitinação/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Camundongos , Masculino , Micafungina/farmacologia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Cardiotoxicidade/prevenção & controle , Cardiotoxicidade/metabolismo , Cardiotoxicidade/etiologia , Miocárdio/metabolismo , Miocárdio/patologiaRESUMO
Though echinocandins are the first line of therapy for C. auris candidemia, there is little clinical data to guide the choice of therapy within this class. This was the first study to compare the three echinocandins in terms of efficacy and outcomes for C. auris candidemia. This was a retrospective analysis of 82 episodes of candidemia caused by C. auris comparing outcomes across the three echinocandins. Majority patients in our study were treated with micafungin. Susceptibility rates were the lowest for caspofungin (35.36% resistance), with no resistance reported for the other two echinocandins. When a susceptible echinocandin was chosen, caspofungin resistance was not a factor significantly associated with mortality. Also, when a susceptible echinocandin was used for therapy, the choice within the class did not affect clinical cure, microbiological cure, or mortality (P > 0.05 for all). Failure to achieve microbiological cure (P = 0.018) and receipt of immune-modulatory therapy (P = 0.01) were significantly associated with increased mortality. Significant cost variation was noted among the echinocandins. Considering the significant cost variation, comparable efficacies can be reassuring for the prescribing physician.
This is the first study comparing efficacy of the three echinocandins in C. auris candidemia. The clinical efficacy of the three echinocandins was found to be comparable. Micafungin and anidulafungin had lower minimum inhibitory concentrations. A significant cost variation was noted.
Assuntos
Antifúngicos , Candidemia , Caspofungina , Equinocandinas , Micafungina , Testes de Sensibilidade Microbiana , Centros de Atenção Terciária , Humanos , Índia , Equinocandinas/uso terapêutico , Equinocandinas/farmacologia , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Candidemia/tratamento farmacológico , Candidemia/mortalidade , Candidemia/microbiologia , Estudos Retrospectivos , Masculino , Feminino , Centros de Atenção Terciária/estatística & dados numéricos , Pessoa de Meia-Idade , Caspofungina/uso terapêutico , Caspofungina/farmacologia , Adulto , Micafungina/uso terapêutico , Micafungina/farmacologia , Resultado do Tratamento , Idoso , Candida auris/efeitos dos fármacos , Farmacorresistência Fúngica , Adulto Jovem , AdolescenteRESUMO
OBJECTIVE: This study aimed to verify oral candidiasis, identify the causative species, and investigate the antifungal susceptibility of yeasts isolated from liver transplant patients. METHODS: A descriptive analysis of 97 patients who underwent liver transplantation was conducted at a hospital. Two clinical examinations (Collections A and B) of the oral cavity were performed. Oral material was collected from all patients, inoculated in Sabouraud Dextrose Agar, and incubated at 35â for 48 hours. Samples were identified by molecular sequencing of the internal trascribed space region of rDNA. RESULTS: An antifungal susceptibility test with fluconazole, amphotericin B, and micafungin was performed using the Clinical and Laboratory Standards Institute yeast broth microdilution method. Among the patients, 15 presented with oral candidiasis: eight in Collection A and seven in Collection B. The primary type of candidiasis was atrophic, followed by pseudomembranous candidiasis. The most prevalent species was Candida albicans (nine), followed by Candida glabrata (three), Candida tropicalis (two), and Candida dubliniensis (one). Regarding susceptibility to fluconazole, of the 15 samples, 11 were susceptible, three were susceptible in a dose-dependent manner, and one was resistant. CONCLUSION: The most commonly identified type of candidiasis was atrophic, with C. albicans and C. glabrata being the most prevalent causative species. One fluconazole-resistant isolate each of C. tropicalis and C. albicans were identified.
Assuntos
Antifúngicos , Candida , Candidíase Bucal , Fluconazol , Transplante de Fígado , Testes de Sensibilidade Microbiana , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Transplante de Fígado/efeitos adversos , Masculino , Candidíase Bucal/microbiologia , Candidíase Bucal/tratamento farmacológico , Feminino , Pessoa de Meia-Idade , Candida/efeitos dos fármacos , Candida/classificação , Candida/isolamento & purificação , Fluconazol/farmacologia , Adulto , Anfotericina B/farmacologia , Idoso , Farmacorresistência Fúngica , Micafungina/farmacologia , Micafungina/uso terapêutico , Adulto JovemRESUMO
Candida parapsilosis complex has recently received special attention due to naturally occurring FKS1 polymorphism associated with high minimal inhibitory concentrations for echinocandin and the increase of clonal outbreaks of strains resistant to commonly used antifungals such as fluconazole. Despite the previous fact, little is known about the genetic mechanism associated with echinocandin resistance. Therefore, the present study was designed to investigate the mechanism of acquired echinocandin resistance in C. parapsilosis complex strains. A total of 15 clinical C. parapsilosis complex isolates were sub-cultured for 30 days at a low concentration of micafungin at ½ the lowest MIC value of the tested isolates (0.12 µg/ml). After culturing, all the isolates were checked phenotypically for antifungal resistance and genotypically for echinocandin resistance by checking FKS1 gene hot spot one (HS1) and HS2 mutations. In vitro induction of echinocandin resistance confirmed the rapid development of resistance at low concentration micafungin, with no difference among C. parapsilosis, C. metapsilosis, and C. orthopsilosis in the resistance development. For the first time we identified different FKS1 HS1 and or HS2 mutations responsible for echinocandin resistance such as R658S and L1376F in C. parapsilosis, S656X, R658X, R658T, W1370X, X1371I, V1371X, and R1373X (corresponding to their location in C. parapsilosis) in C. metapsilosis, and L648F and R1366H in C. orthopsilosis. Our results are of significant concern, since the rapid development of resistance may occur clinically after short-term exposure to antifungals as recently described in other fungal species with the potential of untreatable infections.
Assuntos
Antifúngicos , Candida parapsilosis , Farmacorresistência Fúngica , Equinocandinas , Glucosiltransferases , Humanos , Antifúngicos/farmacologia , Candida parapsilosis/genética , Candida parapsilosis/efeitos dos fármacos , Candidíase/microbiologia , Farmacorresistência Fúngica/genética , Equinocandinas/farmacologia , Proteínas Fúngicas/genética , Glucosiltransferases/genética , Micafungina/farmacologia , Testes de Sensibilidade Microbiana , Mutação , Mutação de Sentido IncorretoRESUMO
Species from Candida parapsilosis complex are frequently found in neonatal candidemia. The antifungal agents to treat this infection are limited and the occurrence of low in vitro susceptibility to echinocandins such as micafungin has been observed. In this context, the chaperone Hsp90 could be a target to reduce resistance. Thus, the objective of this research was to identify isolates from the C. parapsilosis complex and verify the action of Hsp90 inhibitors associated with micafungin. The fungal identification was based on genetic sequencing and mass spectrometry. Minimal inhibitory concentrations were determined by broth microdilution method according to Clinical Laboratory and Standards Institute. The evaluation of the interaction between micafungin with Hsp90 inhibitors was realized using the checkerboard methodology. According to the polyphasic taxonomy, C. parapsilosis sensu stricto was the most frequently identified, followed by C. orthopsilosis and C. metapsilosis, and one isolate of Lodderomyces elongisporus was identified by genetic sequencing. The Hsp90 inhibitor geladanamycin associated with micafungin showed a synergic effect in 31.25% of the isolates, a better result was observed with radicicol, which shows synergic effect in 56.25% tested yeasts. The results obtained demonstrate that blocking Hsp90 could be effective to reduce antifungal resistance to echinocandins.
Assuntos
Antifúngicos , Candida parapsilosis , Candidemia , Proteínas de Choque Térmico HSP90 , Micafungina , Humanos , Recém-Nascido , Antifúngicos/farmacologia , Benzoquinonas/farmacologia , Candida parapsilosis/efeitos dos fármacos , Candida parapsilosis/isolamento & purificação , Candida parapsilosis/genética , Candidemia/microbiologia , Farmacorresistência Fúngica , Sinergismo Farmacológico , Equinocandinas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico HSP90/genética , Lactamas Macrocíclicas/farmacologia , Lipopeptídeos/farmacologia , Micafungina/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Recent epidemiological studies documented an alarming increase in the prevalence of echinocandin-resistant (ECR) Candida glabrata blood isolates. ECR isolates are known to arise from a minor subpopulation of a clonal population, termed echinocandin persisters. Although it is believed that isolates with a higher echinocandin persistence (ECP) are more likely to develop ECR, the implication of ECP needs to be better understood. Moreover, replacing laborious and time-consuming traditional approaches to determine ECP levels with rapid, convenient, and reliable tools is imperative to advance our understanding of this emerging concept in clinical practice. Herein, using extensive ex vivo and in vivo systemic infection models, we showed that high ECP isolates are less effectively cleared by micafungin treatment and exclusively give rise to ECR colonies. Additionally, we developed a flow cytometry-based tool that takes advantage of a SYTOX-based assay for the stratification of ECP levels. Once challenged with various collections of echinocandin-susceptible blood isolates, our assay reliably differentiated ECP levels in vitro and predicted ECP levels in real time under ex vivo and in vivo conditions when compared to traditional methods relying on colony-forming unit counting. Given the high and low ECP predictive values of 92.3% and 82.3%, respectively, our assay showed a high agreement with traditional approach. Collectively, our study supports the concept of ECP level determination in clinical settings and provides a robust tool scalable for high-throughput settings. Application of this tool facilitates the interrogation of mutant and drug libraries to further our understanding of persister biology and designing anti-persister therapeutics. IMPORTANCE: Candida glabrata is a prevalent fungal pathogen able to replicate inside macrophages and rapidly develop resistance against frontline antifungal echinocandins. Multiple studies have shown that echinocandin resistance is fueled by the survival of a small subpopulation of susceptible cells surviving lethal concentrations of echinocandins. Importantly, bacterial pathogens that exhibit high antibiotic persistence also impose a high burden and generate more antibiotic-resistant colonies. Nonetheless, the implications of echinocandin persistence (ECP) among the clinical isolates of C. glabrata have not been defined. Additionally, ECP level determination relies on a laborious and time-consuming method, which is prone to high variation. By exploiting in vivo systemic infection and ex vivo models, we showed that C. glabrata isolates with a higher ECP are associated with a higher burden and more likely develop echinocandin resistance upon micafungin treatment. Additionally, we developed an assay that reliably determines ECP levels in real time. Therefore, our study identified C. glabrata isolates displaying high ECP levels as important entities and provided a reliable and convenient tool for measuring echinocandin persistence, which is extendable to other fungal and bacterial pathogens.
Assuntos
Candida glabrata , Equinocandinas , Equinocandinas/farmacologia , Candida glabrata/genética , Micafungina/farmacologia , Farmacorresistência Fúngica/genética , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Antibacterianos/farmacologiaRESUMO
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/farmacologiaRESUMO
This study aimed to develop and validate a rapid method for identification by MALDI-TOF system and determination of the susceptibility to Fluconazole and Micafungin by broth microdilution among Candidaspecies causing bloodstream infections. Subcultures from blood culture bottles were incubated for 5 hours (+/- 1h) and used to perform the tests, so that the turnaround time of rapid identification and susceptibility profile was about 5 and 24 hours, respectively. The rapid identification showed agreement of 92.05 %. Regarding the rapid broth microdilution for Fluconazole and Micafungin, the agreement was 97.06 % (p<0.001) and 100 % (p<0.001), and the Kappa coefficient was 0.91 (p<0.001) and 1.0 (p<0.001), respectively. To conclude, both rapid methods showed to be reproducible, inexpensive, easy to perform and time-saving. Thus, these methodologies could be useful to guide and adjust empirical antifungal therapy.
Assuntos
Antifúngicos , Hemocultura , Candida , Equinocandinas , Fluconazol , Lipopeptídeos , Micafungina , Testes de Sensibilidade Microbiana , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Micafungina/farmacologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Candida/efeitos dos fármacos , Candida/classificação , Antifúngicos/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Hemocultura/métodos , Lipopeptídeos/farmacologia , Equinocandinas/farmacologia , Fluconazol/farmacologia , Candidemia/microbiologia , Candidemia/diagnóstico , Fatores de Tempo , Reprodutibilidade dos TestesRESUMO
OBJECTIVES: This study aimed to identify the resistance mechanisms to micafungin and fluconazole in a clinical isolate of Candida glabrata. METHODS: The isolate was whole-genome sequenced to identify amino acid changes in key proteins involved in antifungal resistance, and the isolate was further characterised by pathogenicity-related phenotypic assays that supported the sequencing results. RESULTS: Amino acid substitutions were detected in 8 of 17 protein candidates. Many of these substitutions were novel, including in CHS3, CHS3B, and KRE5, which are involved in the development of micafungin resistance. Regarding fluconazole resistance, overexpression of efflux pumps was observed. Our isolate did not exhibit an increased virulence potential compared with the control strain; however, a significant increase in chitin content and potential to resist the cell surface disruptant sodium dodecyl sulphate was observed. CONCLUSIONS: This clinical Candida glabrata isolate experienced a change in cell wall architecture, which correlates with the development of micafungin resistance.
Assuntos
Antifúngicos , Candida glabrata , Quitina , Farmacorresistência Fúngica , Micafungina , Testes de Sensibilidade Microbiana , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Candida glabrata/isolamento & purificação , Antifúngicos/farmacologia , Humanos , Micafungina/farmacologia , Quitina/metabolismo , Quitina/farmacologia , Farmacorresistência Fúngica/genética , Fluconazol/farmacologia , Sequenciamento Completo do Genoma , Candidíase/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Substituição de Aminoácidos , Parede CelularRESUMO
BACKGROUND: Pharmacokinetic/pharmacodynamic (PK/PD) targets of echinocandins failed to support current clinical breakpoints of Candida parapsilosis as the PTA is low for susceptible isolates despite the good clinical efficacy of echinocandins against these infections. We therefore investigated the effect of micafungin against C. parapsilosis using an in vitro PK/PD in the presence of 10% human serum. METHODS: Three susceptible (MIC = 0.5-2 mg/L) and one resistant (MIC > 8 mg/L) C. parapsilosis sensu stricto isolates were tested at two different inocula (104 and 103 cfu/mL) simulating micafungin human exposures in RPMI and in RPMI + 10% pooled human serum. The exposure-effect relationship tAUC0-24/MIC was described and different PK/PD targets were determined in order to calculate the PTA for the standard 100 mg IV q24h dose. RESULTS: A maximal effect was found at fCmax ≥ 4 mg/L in RPMI and tCmax ≥ 64 mg/L (fCmax = 0.08 mg/L) in the presence of serum for which in vitro PK/PD targets were 50 times lower. Stasis in the presence of serum was found at 272-240 tAUC0-24/MIC, close to the clinical PK/PD target (285 tAUC/MIC), validating the in vitro model. However, the PTA was low for susceptible isolates with EUCAST/CLSI MICs ≤ 2 mg/L. Among the different PK/PD targets investigated, the PK/PD target 28 tAUC/MIC associated with 10% of maximal effect with the low inoculum resulted in PTAs ≥ 95% for susceptible isolates with EUCAST/CLSI MICs ≤ 2 mg/L. CONCLUSIONS: A new PK/PD target was found for micafungin and C. parapsilosis that supports the current clinical breakpoint. This target could be used for assessing echinocandin efficacy against C. parapsilosis.
Assuntos
Antifúngicos , Candida parapsilosis , Humanos , Micafungina/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Lipopeptídeos/farmacologia , Candida , Equinocandinas/farmacologia , Mitomicina/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Breast cancer and osteosarcoma are common cancers in women and children, respectively, but ideal drugs for treating patients with breast cancer or osteosarcoma remain to be found. Micafungin is an antifungal drug with antitumor activity on leukemia. Based on the notion of drug repurposing, this study aims to evaluate the antitumor effects of micafungin on breast cancer and osteosarcoma in vitro and in vivo, and to elucidate the underlying mechanisms. Five breast cancer cell lines (MDA-MB-231, BT-549, SK-BR-3, MCF-7, and 4T1) and one osteosarcoma cell line (143B) were chosen for the in vitro studies. Micafungin exerted an inhibitory effect on the viability of all cell lines, and MCF-7 cells were most sensitive to micafungin among the breast cancer cell lines. In addition, micafungin showed an inhibitory effect on the proliferation, clone formation, and migration in MCF7 and 143B cells. The inhibitory effect of micafungin on the growth of breast cancer and osteosarcoma was further confirmed with xenograft tumor mouse models. To explore the underlying mechanisms, the effect of micafungin on epithelial-mesenchymal transition (EMT) was examined. As expected, the levels of matrix metalloproteinase 9 and vimentin in MCF-7 and 143B cells were notably reduced in the presence of micafungin, concomitant with the decreased levels of ubiquitin-specific protease 7 (USP7), p-AKT, and p-GSK-3ß. Based on these observations, we conclude that micafungin exerts antitumor effect on breast cancer and osteosarcoma through preventing EMT in an USP7/AKT/GSK-3ß pathway-dependent manner.
Assuntos
Antineoplásicos , Neoplasias Ósseas , Neoplasias da Mama , Transição Epitelial-Mesenquimal , Glicogênio Sintase Quinase 3 beta , Micafungina , Osteossarcoma , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Osteossarcoma/metabolismo , Humanos , Animais , Glicogênio Sintase Quinase 3 beta/metabolismo , Micafungina/farmacologia , Micafungina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Neoplasias Ósseas/metabolismo , Camundongos Endogâmicos BALB C , Ubiquitina Tiolesterase/metabolismo , Camundongos Nus , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos , Células MCF-7RESUMO
Candida glabrata is believed to be the underlying cause of many human ailments, including oral, gastrointestinal, and vaginal disorders. C. glabrata-caused deep-seated infections, coupled with its resistance to antifungal drugs, may contribute to a high mortality rate. Resveratrol is a polyphenol and can achieve better therapeutic effects when administered in combination with micafungin, but the underlying molecular mechanisms remain unknown. Here, we investigate the effects of varying doses of resveratrol on the proliferation, apoptosis, and activity of macrophages, which were co-cultured with micafungin-pretreated C. glabrata. Resveratrol can restore the decreased proliferative activity of macrophages caused by the phagocytosis of C. glabrata. Further investigations demonstrated that this restoration ability exhibited a dose-dependent manner, reaching the highest level at 200 µM of resveratrol. Resveratrol tended to be more effective in inhibiting macrophage apoptosis and reducing reactive oxygen species (ROS) levels with concentration increases. In addition, at medium concentrations, resveratrol may down-regulate the expression of most inflammatory cytokines, whereas at high concentrations, it started to exert pro-inflammatory functions by up-regulating their expressions. Macrophages may shift from an anti-inflammatory (M2) phenotype to an inflammatory (M1) phenotype by resveratrol at 200 µM, and from M1 to M2 at 400 µM. Our research shows that resveratrol with micafungin are effective in treating C. glabrata infections. The resveratrol-micafungin combination can reduce the production of ROS, and promote the proliferation, inhibit the apoptosis, and activate the polarization of macrophages in a dose-dependent manner. This study offers insights into how this combination works and may provide possible direction for further clinical application of the combination.
Assuntos
Candida glabrata , Equinocandinas , Feminino , Humanos , Micafungina/farmacologia , Candida glabrata/genética , Equinocandinas/farmacologia , Resveratrol/farmacologia , Espécies Reativas de Oxigênio , Antifúngicos/farmacologia , Macrófagos , FagocitoseRESUMO
Candida auris is an emerging fungal pathogen that is feared to spread of infection because of its propensity for multidrug resistance and high mortality rate. This pathogenic yeast is classified into four major clades by phylogenetic analyses, which are referred to the South Asia clade (clade I), East Asia clade (clade II), South Africa clade (clade III), and South America clade (clade IV), based on the location of the initial isolate. In this study, we evaluated the virulence of C. auris strains belonging to four major clades and the therapeutic effects of micafungin in a silkworm infection model. The highest mortality rate at 21 h after C. auris inoculation was observed for strains from clade IV (80% or more). In contrast, it was 20% or less in those from other clades. Antifungal susceptibility tests indicated resistance to fluconazole and sensitivity to echinocandins in the blood-derived strains. Micafungin prolonged the survival of blood-derived C. auris infected silkworms. These results suggest that the silkworm infection model is useful for evaluating the virulence of C. auris and determining its therapeutic effects.
Candida auris is an emerging fungal pathogen that has spread worldwide because of its multidrug resistance. We developed a silkworm infection model with C. auris to evaluate the virulence of clinical isolates. An evaluation system using silkworms is useful for determining C. auris virulence.
Assuntos
Bombyx , Candidíase , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Micafungina/farmacologia , Candida , Candidíase/microbiologia , Candidíase/veterinária , Candida auris , Virulência , Filogenia , Testes de Sensibilidade Microbiana/veterináriaRESUMO
Neddylation is a protein modification process similar to ubiquitination, carried out through a series of activating (E1), conjugating (E2), and ligating (E3) enzymes. This process has been found to be overactive in various cancers, leading to increased oncogenic activities. Ubiquitin-conjugating enzyme 2 M (UBE2M) is one of two neddylation enzymes that play a vital role in this pathway. Studies have shown that targeting UBE2M in cancer treatment is crucial, as it regulates many molecular mechanisms like DNA damage, apoptosis, and cell proliferation. However, developing small molecule inhibitors against UBE2M remains challenging due to the lack of suitable druggable pockets. We have discovered that Micafungin, an antifungal agent that inhibits the production of 1,3-ß-D-glucan in fungal cell walls, acts as a neddylation inhibitor that targets UBE2M. Biochemical studies reveal that Micafungin obstructs neddylation and stabilizes UBE2M. In cellular experiments, the drug was found to interact with UBE2M, prevent neddylation, accumulate cullin ring ligases (CRLs) substrates, reduce cell survival and migration, and induce DNA damage in gastric cancer cells. This research uncovers a new anti-cancer mechanism for Micafungin, paving the way for the development of a novel class of neddylation inhibitors that target UBE2M.
Assuntos
Antifúngicos , Neoplasias , Antifúngicos/farmacologia , Apoptose , Núcleo Celular , Proliferação de Células , Micafungina/farmacologia , Enzimas de Conjugação de Ubiquitina/química , Enzimas de Conjugação de Ubiquitina/metabolismoRESUMO
The objective of this study was to evaluate the efficacy of various micafungin dosing regimens against Candida spp. in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). Monte Carlo simulations were conducted using pharmacokinetic (PK) parameters and pharmacodynamic (PD) data to determine the probabilities of target attainment and cumulative fractions of response in terms of area under the concentration curve/minimum inhibition concentration targets of micafungin. Current standard clinical micafungin dosing regimens of 1 and 2 mg/kg/day were appropriate for the prevention and treatment of Candida glabrata infection in pediatric patients undergoing HSCT, respectively. Moreover, the high-dose prophylactic dosage (2 mg/kg/day) and therapeutic dosage (4 mg/kg/day) should be the preferred option to optimize efficacy against Candida albicans. However, none of the simulated regimens was effective against Candida parapsilosis in pediatric HSCT patients. These PK/PD-based simulations rationalize and optimize the micafungin dosing regimens against Candida spp. in pediatric patients undergoing HSCT.
Assuntos
Candidíase , Transplante de Células-Tronco Hematopoéticas , Humanos , Criança , Micafungina/farmacologia , Candida , Antifúngicos/uso terapêutico , Equinocandinas/uso terapêutico , Método de Monte Carlo , Candidíase/tratamento farmacológico , Testes de Sensibilidade Microbiana , Lipopeptídeos/uso terapêuticoRESUMO
BACKGROUND: The CLSI breakpoint for micafungin and Candida albicans is 0.25 mg/L, higher than the CLSI epidemiological cut-off value (0.03 mg/L) whereas the EUCAST values are identical (0.016 mg/L). We developed a novel in vitro dialysis-diffusion pharmacokinetic/pharmacodynamic (PK/PD) model, confirmed correlation to in vivo outcome and studied micafungin pharmacodynamics against Canida albicans. METHODS: Four C. albicans isolates, including a weak (F641L) and a strong (R647G) fks1 mutants, were studied using a 104 cfu/mL inoculum and RPMI medium with and without 10% pooled human serum. The exposure-effect relationship fAUC0-24/MIC was described for CLSI and EUCAST methodology. Monte Carlo simulation analysis included standard (100 mg i.v.) and higher (150-300 mg) doses q24h to determine the corresponding probability of target attainment (PTA). RESULTS: The in vitro PK/PD targets for stasis/1-log kill were 36/57 fAUC0-24/MIC in absence and 2.8/9.2 fAUC0-24/MIC in the presence of serum, and similar for wild-type and fks mutant isolates. The PTAs for both PK/PD targets were high (>95%) for EUCAST susceptible isolates but not for CLSI susceptible non-wild-type isolates (CLSI MICs 0.06-0.25 mg/L). 300 mg q24h was needed to attain PK/PD targets for non-wild-type isolates with CLSI MICs 0.06-0.125 mg/L and EUCAST MICs 0.03-0.06 mg/L. CONCLUSION: The in vitro 1-log kill effect corresponded to stasis in animal model and mycological response in patients with invasive candidiasis, thereby validating the model for studying pharmacodynamics of echinocandins in vitro. EUCAST breakpoints were well supported by our findings but our data questions whether the current CLSI breakpoint, which is higher than the epidemiological cut-off values, is appropriate.
Assuntos
Candida albicans , Candidíase Invasiva , Animais , Humanos , Micafungina/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Equinocandinas/farmacologia , Candidíase Invasiva/tratamento farmacológico , Testes de Sensibilidade MicrobianaRESUMO
Candida auris is resistant to multiple antifungal agents. This study investigated its antifungal susceptibility and explored FKS1 mutations across the isolates from mice enterically colonized with wild-type C. auris and treated with echinocandin. Resistant C. auris with FKS1 mutations, including S639F, S639Y, D642Y, R1354H, or R1354Y, were isolated and found to be micafungin- and caspofungin-resistant in vivo; however, the MICs of isolates with mutation in R1354 remained below the micafungin breakpoint in vitro.
Assuntos
Candida auris , Equinocandinas , Animais , Camundongos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica/genética , Equinocandinas/farmacologia , Equinocandinas/genética , Trato Gastrointestinal , Micafungina/farmacologia , Testes de Sensibilidade Microbiana , Mutação/genéticaRESUMO
Echinocandin antifungal drugs, including micafungin, anidulafungin, and caspofungin, have been recently reported to exhibit antiviral effects against various viruses such as flavivirus, alphavirus, and coronavirus. In this study, we focused on micafungin and its derivatives and analyzed their antiviral activities against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The micafungin derivatives Mi-2 and Mi-5 showed higher antiviral activity than micafungin, with 50% maximal inhibitory concentration (IC50) of 5.25 and 6.51 µM, respectively (3.8 to 4.7-fold stronger than micafungin) and 50% cytotoxic concentration (CC50) of >64 µM in VeroE6/TMPRSS2 cells. This high anti-SARS-CoV-2 activity was also conserved in human lung epithelial cell-derived Calu-3 cells. Micafungin, Mi-2, and Mi-5 were suggested to inhibit the intracellular virus replication process; additionally, these compounds were active against SARS-CoV-2 variants, including Delta (AY.122, hCoV-19/Japan/TY11-927/2021), Omicron (BA.1.18, hCoV-19/Japan/TY38-873/2021), a variant resistant to remdesivir (R10/E796G C799F), and a variant resistant to casirivimab/imdevimab antibody cocktail (E406W); thus, our results provide basic evidence for the potential use of micafungin derivatives for developing antiviral agents.
Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/farmacologia , Micafungina/farmacologia , Replicação do RNA , RNA Viral , SARS-CoV-2RESUMO
Procedures such as solid-organ transplants and cancer treatments can leave many patients in an immunocompromised state. This leads to their increased susceptibility to opportunistic diseases such as fungal infections. Mucormycosis infections are continually emerging and pose a serious threat to immunocompromised patients. Recently there has been a sharp increase in mucormycosis cases as a secondary infection in patients battling severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Mucorales fungi are notorious for presenting resistance to most antifungal drugs. The absence of effective means to treat these infections results in mortality rates approaching 100% in cases of disseminated infection. One of the most effective antifungal drug classes currently available is the echinocandins. Echinocandins seem to be efficacious in the treatment of many other fungal infections. Unfortunately, susceptibility testing has found that echinocandins have little to no effect on Mucorales fungi. In this study, we found that the model Mucorales Mucor circinelloides genome carries three copies of the genes encoding the echinocandin target protein ß-(1,3)-d-glucan synthase (fksA, fksB, and fksC). Interestingly, we found that exposing M. circinelloides to micafungin significantly increased the expression of the fksA and fksB genes, resulting in an increased accumulation of ß-(1,3)-d-glucan on the cell walls. However, this overexpression of the fks genes is not directly connected to the intrinsic resistance. Subsequent investigation discovered that the serine/threonine phosphatase calcineurin regulates the expression of fksA and fksB, and the deletion of calcineurin results in a decrease in expression of all three fks genes. Deletion of calcineurin also results in a lower minimum effective concentration (MEC) of micafungin. In addition, we found that duplication of the fks gene is also responsible for the intrinsic resistance, in which lack of either fksA or fksB led a lower MEC of micafungin. Together, these findings demonstrate that calcineurin and fks gene duplication contribute to the intrinsic resistance to micafungin we observe in M. circinelloides.
Assuntos
COVID-19 , Mucormicose , Micoses , Humanos , Micafungina/farmacologia , Micafungina/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Mucormicose/tratamento farmacológico , Mucormicose/microbiologia , Calcineurina/genética , Calcineurina/farmacologia , SARS-CoV-2 , Mucor/genética , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Micoses/tratamento farmacológico , Serina , Farmacorresistência Fúngica/genéticaRESUMO
Fungi are becoming increasingly resistant, especially the new strains. Therefore, this work developed nanoemulsions (NE) containing micafungin (MICA), in order to improve its action against infections caused by Candida auris. The NEs were composed of the surfactants polyoxyethylene (20) cetyl ether (Brij 58®)/soy phosphatidylcholine at 10%, sunflower oil/cholesterol at 10%, and 80% PBS. The NEs were characterized by Dynamic Light Scattering (DLS). For the microbiological in vitro evaluation the determination of the minimum inhibitory concentration (MIC), ergosterol/sorbitol, time kill and biofilms tests were performed. Additionally, the antifungal activity was also evaluated in a Galleria mellonella model. The same model was used in order to evaluate acute toxicity. The NE showed a size of â¼ 42.12 nm, a polydispersion index (PDI) of 0.289, and a zeta potential (ZP) of -3.86 mV. NEM had an average size of 41.29 nm, a PDI of 0.259, and a ZP of -4.71 mV. Finally, both nanoemulsions showed good stability in a storage period of 3 months. Although NEM did not show activity in planktonic cells, it exhibited action against biofilm and in the in vivo infection model. In the alternative in vivo model assay, it was possible to observe that both, NEM and free MICA at 0.2 mg/l, was effective against the infection, being that NEM presented a better action. Finally, NEM and free MICA showed no acute toxicity up to 4 mg/l. NEM showed the best activities in in vitro in mature antibiofilm and in alternative in vivo models in G. mellonella. Although, NEs showed to be attractive for MICA transport in the treatment of infections caused by C. auris in vitro and in vivo studies with G. mellonella, further studies should be carried out, in mice, for example.
Candida auris is a fungus that can cause infections in the human body. As it is a microorganism with a high potential for resistance, it is extremely important to develop new therapeutic alternatives. Thus, nanotechnology, the science that studies materials with extremely small sizes, can be considered a promising method in the treatment of these infections.