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Single-cell sequencing was developed as a high-throughput tool to elucidate unusual and transient cell states that are barely visible in the bulk. This technology reveals the evolutionary status of cells and differences between populations, helps to identify unique cell subtypes and states, reveals regulatory relationships between genes, targets and molecular mechanisms in disease processes, tumor heterogeneity, the state of the immune environment, etc. However, the high cost and technical limitations of single-cell sequencing initially prevented its widespread application, but with advances in research, numerous new single-cell sequencing techniques have been discovered, lowering the cost barrier. Many single-cell sequencing platforms and bioinformatics methods have recently become commercially available, allowing researchers to make fascinating observations. They are now increasingly being used in various industries. Several protocols have been discovered in this context and each technique has unique characteristics, capabilities and challenges. This review presents the latest advancements in single-cell transcriptomics technologies. This includes single-cell transcriptomics approaches, workflows and statistical approaches to data processing, as well as the potential advances, applications, opportunities and challenges of single-cell transcriptomics technology. You will also get an overview of the entry points for spatial transcriptomics and multi-omics.
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Biología Computacional , Perfilación de la Expresión Génica , Análisis de la Célula Individual , Transcriptoma , Análisis de la Célula Individual/métodos , Humanos , Perfilación de la Expresión Génica/métodos , Biología Computacional/métodos , Transcriptoma/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , AnimalesRESUMEN
Engineering polymer-based nano-systems have attracted many researchers owing to their unique qualities like shape, size, porosity, mechanical strength, biocompatibility, and biodegradability. Both natural and synthetic polymers can be tuned to get desired surface chemistry and functionalization to improve the efficacy of cancer therapy by promoting targeted delivery to the tumor site. Recent advancements in cancer immunoediting have been able to manage both primary tumor and metastatic lesions via activation of the immune system. The combinations of nano-biotechnology and immunotherapeutic agents have provided positive outcomes by enhancing the host immune response in cancer therapy. The nanoparticles have been functionalized using antibodies, targeted antigens, small molecule ligands, and other novel agents that can interact with biological systems at nanoscale levels. Several polymers, such as polyethylene glycol (PEG), poly(lactic-co-glycolic acid) (PLGA), poly(ε-caprolactone) (PCL), and chitosan, have been approved by the Food and Drug Administration for clinical use in biomedicine. The polymeric nanoformulations such as polymers-antibody/antigen conjugates and polymeric drug conjugates are currently being explored as nanomedicines that can target cancer cells directly or target immune cells to promote anti-cancer immunotherapy. In this review, we focus on scientific developments and advancements on engineered polymeric nano-systems in conjugation with immunotherapeutic agents targeting the tumor microenvironment to improve their efficacy and the safety for better clinical outcomes.
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Nanopartículas , Neoplasias , Humanos , Polímeros/química , Polímeros/uso terapéutico , Sistemas de Liberación de Medicamentos , Polietilenglicoles/química , Neoplasias/tratamiento farmacológico , Inmunoterapia , Nanopartículas/química , Microambiente TumoralRESUMEN
In breast cancer, mAbs can play multifunctional roles like targeting cancer cells, sometimes directly attacking them, helping in locating and delivering therapeutic drugs to targets, inhibiting cell growth and blocking immune system inhibitors, etc. Monoclonal antibodies are also one of the important successful treatment strategies especially against HER2 but they have not been explored much for other types of breast cancers especially in triple negative breast cancers. Monoclonal antibodies impact the feasibility of antigen specificity, bispecific and trispecific mAbs have opened new doors for more targeted specific efficacy. Monoclonal antibodies can be used diversly and with efficacy as compared to other methods of treatment thus maining it a suitable candidate for breast cancer treatment. However, mAbs treatment also causes various side effects such as fever, trembling, fatigue, headache and muscle pain, nausea/vomiting, difficulty in breathing, rashes and bleeding. Understanding the pros and cons of this strategy, we have explored in this review, the current and future potential capabilities of monoclonal antibodies with respect to diagnosis and treatment of breast cancer. DATA AVAILABILITY: Not applicable.
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Neoplasias de la Mama , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Anticuerpos Monoclonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Proliferación CelularRESUMEN
Combating triple-negative breast cancer (TNBC) is still a problem, despite the development of numerous drug delivery approaches. Mucin1 (MUC1), a glycoprotein linked to chemo-resistance and progressive malignancy, is unregulated in TNBC. GO-201, a MUC1 peptide inhibitor that impairs MUC1 activity, promotes necrotic cell death by binding to the MUC1-C unit. The current study deals with the synthesis and development of a novel nano-formulation (DM-PEG-PCL NPs) comprising of polyethylene glycol-polycaprolactone (PEG-PCL) polymer loaded with MUC1 inhibitor and an effective anticancer drug, doxorubicin (DOX). The DOX and MUC1 loaded nanoparticles were fully characterized, and their different physicochemical properties, viz. size, shape, surface charge, entrapment efficiencies, release behavior, etc., were determined. With IC50 values of 5.8 and 2.4 nm on breast cancer cell lines, accordingly, and a combination index (CI) of < 1.0, DM-PEG-PCL NPs displayed enhanced toxicity towards breast cancer cells (MCF-7 and MDA-MB-231) than DOX-PEG-PCL and MUC1i-PEG-PCL nanoparticles. Fluorescence microscopy analysis revealed DOX localization in the nucleus and MUC1 inhibitor in the mitochondria. Further, DM-PEG-PCL NPs treated breast cancer cells showed increased mitochondrial damage with enhancement in caspase-3 expression and reduction in Bcl-2 expression.In vivo evaluation using Ehrlich Ascites Carcinoma bearing mice explicitly stated that DM-PEG-PCL NPs therapy minimized tumor growth relative to control treatment. Further, acute toxicity studies did not reveal any adverse effects on organs and their functions, as no mortalities were observed. The current research reports for the first time the synergistic approach of combination entrapment of a clinical chemotherapeutic (DOX) and an anticancer peptide (MUC1 inhibitor) encased in a diblock PEG-PCL copolymer. Incorporating both DOX and MUC1 inhibitors in PEG-PCL NPs in the designed nanoformulation has provided chances and insights for treating triple-negative breast tumors. Our controlled delivery technology is biodegradable, non-toxic, and anti-multidrug-resistant. In addition, this tailored smart nanoformulation has been particularly effective in the therapy of triple-negative breast cancer. Supplementary Information: The online version contains supplementary material available at 10.1007/s10924-022-02654-4.
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BACKGROUND: Chemotherapeutic drugs are principally intended to treat breast cancer. However, sooner or later, tumor drug resistance developed. These chemo drugs are effective but with numerous side effects. Breast cancer care may be extremely difficult since recurring cancer is frequently pre-treated with powerful agents. Cancer cells acquire high resistance to earlier therapies, necessitating alternative and more powerful drugs. Nanoparticles (NPs) as a medication delivery technology can overcome medication resistance in breast cancer and significantly reduce the effective dose. The off-targeted nature of chemo drugs can be resolved by encapsulating or attaching chemo drugs in nanocarriers, specifically targeting breast cancer cells. OBJECTIVES: This review highlights various chemo drugs for breast cancer and their encapsulation or bioconjugation with nanoparticles for its targeted delivery. CONCLUSION: Nanoparticles may subsist valuable abet in breast cancer management in this regard. Given that traditional chemotherapy approaches have been demonstrated to have several side effects and defects during treatment, the NPs-mediated drug delivery mechanism is a possible contender for replacement as a new technique.
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Antineoplásicos , Neoplasias de la Mama , Nanopartículas , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Sistemas de Liberación de Medicamentos/métodos , Antineoplásicos/farmacología , Portadores de Fármacos , Resistencia a AntineoplásicosRESUMEN
Colorectal cancer is the second leading cause of cancer deaths worldwide and has engrossed researchers' attention toward its detection and prevention at early stages. Primarily associated with genetic and environmental risk factors, the disease has also shown its emergence due to dysbiosis in microbiota. The microbiota not only plays a role in modulating the metabolisms of metastatic tissue but also has a keen role in cancer therapy. The immune cells are responsible for secreting various chemokines and cytokines, and activating pattern recognition receptors by different microbes can lead to the trail by which these cells regulate cancer. Furthermore, mixed immune reactions involving NK cells, tumor-associated macrophages, and lymphocytes have shown their connection with the microbial counterpart of the disease. The microbes like Bacteroides fragilis, Fusobacterium nucleatum, and Enterococcus faecalis and their metabolites have engendered inflammatory reactions in the tumor microenvironment. Hence the interplay between immune cells and various microbes is utilized to study the changing metastasis stage. Targeting either immune cells or microbiota could not serve as a key to tackling this deadly disorder. However, harnessing their complementation towards the disease can be a powerful weapon for developing therapy and diagnostic/prognostic markers. In this review, we have discussed various immune reactions and microbiome interplay in CRC, intending to evaluate the effectiveness of chemotherapy and immunotherapy and their parallel relationship.
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Neoplasias del Colon , Neoplasias Colorrectales , Microbioma Gastrointestinal , Microbiota , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Microbioma Gastrointestinal/fisiología , Sistema Inmunológico , Microambiente TumoralRESUMEN
Now-a-days fungal infection emerges as a significant problem to healthcare management systems due to high frequency of associated morbidity, mortality toxicity, drug-drug interactions, and resistance of the antifungal agents. Aspergillus is the most common mold that cause infection in immunocompromised hosts. It's a hyaline mold that is cosmopolitan and ubiquitous in nature. Aspergillus infects around 10 million population each year with a mortality rate of 30-90%. Clinically available antifungal formulations are restricted to four classes (i.e., polyene, triazole, echinocandin, and allylamine), and each of them have their own limitations associated with the activity spectrum, the emergence of resistance, and toxicity. Consequently, novel antifungal agents with modified and altered chemical structures are required to combat these invasive fungal infections. To overcome these limitations, there is an urgent need for new antifungal agents that can act as potent drugs in near future. Currently, some compounds have shown effective antifungal activity. In this review article, we have discussed all potential antifungal therapies that contain old antifungal drugs, combination therapies, and recent novel antifungal formulations, with a focus on the Aspergillus associated infections.
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Antifúngicos , Aspergilosis , Micosis , Humanos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergilosis/microbiología , Aspergillus , Farmacorresistencia Fúngica , Equinocandinas/farmacología , Equinocandinas/uso terapéutico , Micosis/tratamiento farmacológicoRESUMEN
In breast cancer therapy, Gemcitabine (Gem) is an antineoplastic antimetabolite with greater anticancer efficacy and tolerability. However, effectiveness of Gem is limited by its off-target effects. The synergistic potential of MUC1 (mucin 1) inhibitors and Gem-loaded polymeric nanoparticles (NPs) was discussed in this work in order to reduce dose-related toxicities and enhance the therapeutic efficacy. The double emulsion solvent evaporation method was used to prepare poly(ethylene glycol) methyl ether-block-poly-caprolactone (PEG-PCL)-loaded Gem and MUC 1 inhibitor NPs. The average size of Gem and MUC 1 inhibitor-loaded NPs was 128 nm, with a spherical shape. Twin-loaded NPs containing Gem and the MUC1 inhibitor decreased IC50 and behaved synergistically. Furthermore, in vitro mechanistic studies, that is, loss of MMP, clonogenic assay, Annexin V FITC assay, and Western blotting to confirm apoptosis with simultaneous induction of autophagy using acridine orange (AO) staining were performed in this study. Furthermore, the investigated NPs upon combination exhibited greater loss of MMP and decreased clonogenic potential with simultaneous induction of autophagy in MCF-7 cells. Annexin V FITC clearly showed the percentage of apoptosis while Western blotting protein expression analysis revealed an increase in caspase-3 activity with simultaneous decrease in Bcl-2 protein expression, a hallmark of apoptosis. The effectiveness of the Ehrlich ascites solid (EAT) mice treated with Gem-MUC1 inhibitor NPs was higher than that of the animals treated alone. Overall, the combined administration of Gem and MUC1 inhibitor-loaded NPs was found to be more efficacious than Gem and MUC1 inhibitor delivered separately.
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Neoplasias de la Mama , Nanopartículas , Animales , Anexina A5/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Desoxicitidina/análogos & derivados , Femenino , Fluoresceína-5-Isotiocianato , Humanos , Ratones , Mucina-1 , Poliésteres , Polietilenglicoles , GemcitabinaRESUMEN
Fungal infections have shown an upsurge in recent decades, which is mainly because of the increasing number of immunocompromised patients and the occurrence of invasive candidiasis has been found to be 7-15 fold greater than that of invasive aspergillosis. The genus Candida comprises more than 150 distinct species, however, only a few of them are found to be pathogenic to humans. Mortality rates of Candida species are found to be around 45% and the reasons for this intensified mortality are inefficient diagnostic techniques and unfitting initial treatment strategies. There are only a few antifungal drug classes that are employed for the remedy of invasive fungal infections. which include azoles, polyenes, echinocandins, and pyrimidine analogs. During the last 2-3 decades, the usage of antifungal drugs has increased several folds due to which the reports of escalating antifungal drug resistance have also been recorded. The resistance is mostly to the triazole- based compounds. Due to the occurrence of antifungal drug resistance, the success rates of treatment have been reduced as well as major changes have been observed in the frequency of fungal infections. In this review, we have summarized the major molecular mechanisms for the development of antifungal drug resistance.
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Candida , Micosis , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Farmacorresistencia Fúngica , Equinocandinas/farmacología , Equinocandinas/uso terapéutico , Humanos , Pruebas de Sensibilidad Microbiana , Micosis/tratamiento farmacológicoRESUMEN
Fungi are recognized as key pathogens in immunocompromised patients. The invasive infection always remains a problem for clinicians due to high morbidity and mortality. The treatments of fungal infections are hampered by conventional drugs, which are associated with resistance. Drug resistance has become an important problem in a variety of infectious diseases. The rise in the incidence of fungal infections and drug resistance has intensified the need for alternative therapies that affect a new target. This new target must be a growth essential gene product like the stress pathway. It has been found that stress pathways can be a potential target in opportunistic fungal infection, which played an important role in the virulence of pathogens. It was helpful in protection from host defense, normal fungal growth, and antifungal drug resistance. The disruption of the pathway using alternative strategies (chemosensitization and photo-dynamics therapy) can be a novel approach in fighting fungal infections and for drug design.
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Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Hongos/efectos de los fármacos , Micosis/tratamiento farmacológico , Micosis/microbiología , Animales , Diseño de Fármacos , Farmacorresistencia Fúngica/efectos de los fármacos , Humanos , Virulencia/efectos de los fármacosRESUMEN
The escalating emergence and prevalence of infections caused by multi-drug resistant (MDR) pathogenic bacteria accentuate the crucial need to develop novel and effectual therapeutic strategies to control this threat. The recent past surprisingly indicates a staggering decline in effective strategies against MDR. Different approaches have been employed to minimize the effect of resistance, but the question still lingers over the astounding number of drugs already tried and tested. Furthermore, the detection of new drug targets and the action of new antibacterial agents against already existing drug targets also complicate the condition. Antibiotic adjuvants are considered as one such promising approach for overcoming bacterial resistance. Adjuvants can potentiate the action of generally adopted antibacterial drugs against MDR bacterial pathogens either by minimizing the impact and emergence of resistance or improving the action of antibacterial drugs. This review provides an overview of the mechanism of antibiotic resistance, the main types of adjuvants and their mode of action, achievements and progression.
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Antibacterianos , Infecciones Bacterianas , Farmacorresistencia Bacteriana Múltiple , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , HumanosRESUMEN
BACKGROUND: The major concern of today's time is the developing resistance in most of the clinically derived pathogenic micro-organisms for available drugs through several mechanisms. Therefore, there is a dire need to develop novel molecules with drug-like properties that can be effective against the otherwise resistant micro-organisms. METHODS: New drugs can be developed using several methods like structure-based drug design, ligandbased drug design, or by developing analogs of the available drugs to further improve their effects. However, the smartness is to opt for the techniques that have comparatively less expenditure, lower failure rates, and faster discovery rates. RESULTS: Analog-Based Drug Design (ABDD) is one such technique that researchers worldwide are opting to develop new drug-like molecules with comparatively lower market values. They start by first designing the analogs sharing structural and pharmacological similarities to the existing drugs. This method embarks on scaffold structures of available drugs already approved by the clinical trials, but are left ineffective because of resistance developed by the pathogens. CONCLUSION: In this review, we have discussed some recent examples of anti-fungal and anti-bacterial (antimicrobial) drugs that were designed based on the ABDD technique. Also, we have tried to focus on the in silico tools and techniques that can contribute to the designing and computational screening of the analogs, so that these can be further considered for in vitro screening to validate their better biological activities against the pathogens with comparatively reduced rates of failure.
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Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Diseño de Fármacos , Descubrimiento de Drogas/métodos , Simulación por Computador , HumanosRESUMEN
The existence of the multi-drug resistant (MDR) pathogenic fungus, Candida auris came to light in 2009. This particular organism is capable of causing nosocomial infections in immunecompromised persons. This pathogen is associated with consistent candidemia with high mortality rate and presents a serious global health threat. Whole genome sequence (WGS) investigation detected powerful phylogeographic Candida auris genotypes which are specialized to particular geological areas indicating dissemination of particular genotype among provinces. Furthermore, this organism frequently exhibits multidrug-resistance and displays an unusual sensitivity profile. Identification techniques that are commercialized to test Candida auris often show inconsistent results and this misidentification leads to treatment failure which complicates the management of candidiasis. Till date, Candida auris has been progressively recorded from several countries and therefore its preventive control measures are paramount to interrupt its transmission. In this review, we discussed prevalence, biology, drug-resistance phenomena, virulence factors and management of Candida auris infections.
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Candida/genética , Candida/patogenicidad , Candidiasis/tratamiento farmacológico , Candidiasis/epidemiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Adolescente , Adulto , Anciano , Antifúngicos/farmacología , Candida/citología , Candida/efectos de los fármacos , Candidiasis/microbiología , Candidiasis/prevención & control , Niño , Preescolar , Infección Hospitalaria/microbiología , Infección Hospitalaria/prevención & control , Farmacorresistencia Fúngica Múltiple/genética , Farmacorresistencia Fúngica Múltiple/fisiología , Femenino , Salud Global , Humanos , Lactante , Recién Nacido , Control de Infecciones , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Factores de Virulencia , Adulto JovenRESUMEN
Ageratum conyzoides L. (Asteraceae) is an invasive aromatic herb with immense therapeutic importance. The herb is distributed in tropical and subtropical regions. A. conyzoides has imparted numerous ethnomedicinal uses because it has been used to cure various ailments that include leprosy, skin disorders, sleeping sickness, rheumatism, headaches, dyspnea, toothache, pneumonia and many more. A number of phytoconstituents have been scrutinized such as alkaloids, flavonoids, terpenes, chromenes, and sterols from almost every part of this plant. These phytoconstituents have shown diverse pharmacological properties including antimicrobial, anti-inflammatory, analgesic, antioxidant, anticancer, antiprotozoal, antidiabetic, spasmolytic, allelopathy, and many more. The plant A. conyzoides has provided a platform for doing pharmaceutical and toxicological research in order to isolate some promising active compounds and authenticate their safety in clinical uses. A. conyzoides provides principal information for advanced studies in the field of pharmaceutical industries and agriculture. Present review article describes the cytogenetics, ethnobotany, phytochemistry, pharmacology, and toxicological aspects of A. conyzoides.
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Ageratum/química , Etnofarmacología/métodos , Fitoquímicos/uso terapéutico , Fitoterapia/métodos , Humanos , Fitoquímicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacologíaRESUMEN
BACKGROUND: Protein-Protein interaction (PPI) network analysis of virulence proteins of Aspergillus fumigatus is a prevailing strategy to understand the mechanism behind the virulence of A. fumigatus. The identification of major hub proteins and targeting the hub protein as a new antifungal drug target will help in treating the invasive aspergillosis. MATERIALS & METHOD: In the present study, the PPI network of 96 virulence (drug target) proteins of A. fumigatus were investigated which resulted in 103 nodes and 430 edges. Topological enrichment analysis of the PPI network was also carried out by using STRING database and Network analyzer a cytoscape plugin app. The key enriched KEGG pathway and protein domains were analyzed by STRING. CONCLUSION: Manual curation of PPI data identified three proteins (PyrABCN-43, AroM-34, and Glt1- 34) of A. fumigatus possessing the highest interacting partners. Top 10% hub proteins were also identified from the network using cytohubba on the basis of seven algorithms, i.e. betweenness, radiality, closeness, degree, bottleneck, MCC and EPC. Homology model and the active pocket of top three hub proteins were also predicted.
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Antifúngicos/farmacología , Aspergilosis/tratamiento farmacológico , Aspergillus/patogenicidad , Descubrimiento de Drogas , Proteínas Fúngicas/fisiología , Mapas de Interacción de Proteínas , Factores de Virulencia , Antifúngicos/uso terapéutico , Simulación por Computador , HumanosRESUMEN
BACKGROUND: The impact of fungal infections on human health has increased considerably within a past few decades. Although drugs with antifungal properties are available, but they are less effective and are associated with side effects. OBJECTIVE AND METHOD: To screen the bacterial isolates from Sesamum indicum and to investigate the antifungal activity of the screened bacterial isolates against Aspergillus sp. Co-culture assay and agar overlay were used to scrutinize the anti-Aspergillus activity. Furthermore, optimization of media and growth conditions to enhance the production of anti-Aspergillus compound. RESULTS: Several bacterial cultures were isolated from Sesamum indicum rhizosphere collected from Mandi (H.P.) India. These bacterial cultures were assayed for antifungal activity against Aspergillus species i.e. A. fumigatus and A. niger. Two most potent strains were chosen for more detailed analyses. The biochemical characterization and 16S ribosomal RNA sequencing revealed that Burkholderia sp. strain RC1 and Acinetobacter pittii strain RC2 exhibit strong similarity (100%) with Burkholderia sp. SR2-07 and Acinetobacter sp. strain 3-59. Additionally, it was also validated that RC1 and RC2 showed significant difference in the production of anti-Aspergillusactivity under altered growth conditions. CONCLUSION: Results from this study recommend that plant rhizosphere remains a rich hotspot for delivering a novel antifungal compounds.
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Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Raíces de Plantas/microbiología , Rizosfera , Sesamum/microbiología , Antifúngicos/química , Aspergillus/metabolismo , Relación Dosis-Respuesta a Droga , India , Pruebas de Sensibilidad Microbiana , Raíces de Plantas/metabolismo , Sesamum/metabolismo , Relación Estructura-ActividadRESUMEN
Due to the limited array of the currently available copper chelators, research of such compounds continues to be of clinical interest. Notably, o-dihydroxycoumarins have been previously shown to be potent iron chelators under neutral conditions. Within this study, the interaction of a series of natural coumarins and their synthetic analogs with copper has been evaluated in order to obtain structure-activity relationships under different pathophysiological pH conditions. Both competitive and non-competitive methods have been employed. Analysis of cupric ion reduction has also been performed. Under mildly competitive conditions, cupric chelation was observed for o-dihydroxycoumarins, and partially for o-diacetoxycoumarin. Non-competitive studies showed that cuprous ions are not chelated at all and that the stoichiometries of the most active 6,7- and 7,8-dihydroxycoumarins to cupric ions ranged from 1:1 to 2:1 depending on pH and concentration. Interestingly, under highly competitive conditions, coumarins were not capable of chelating cupric ions, either. Reduction experiments have shown that 13 out of the 15 coumarins included in this study reduced cupric ions. However, significant differences depending on their structures were apparent in their potencies. O-dihydroxycoumarins were the most potent ones again. CONCLUSION: O-dihydroxycoumarins are moderately active cupric ion chelators with potent copper reducing properties.
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Quelantes/química , Cobre/análisis , Cumarinas/química , Colorantes Fluorescentes/química , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Espectrometría de Fluorescencia/métodos , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
Despite recent advances in diagnostic and therapeutic methods in antifungal research, aspergillosis still remains a leading cause of morbidity and mortality. One strategy to address this problem is to enhance the activity spectrum of known antifungals, and we now report the first successful application of Candida antarctica lipase (CAL) for the preparation of optically enriched fluconazole analogues. Anti-Aspergillus activity was observed for an optically enriched derivative, (-)-S-2-(2',4'-difluorophenyl)-1-hexyl-amino-3-(1â´,2â´,4â´)triazol-1â´-yl-propan-2-ol, which exhibits MIC values of 15.6 µg/ml and 7.8 µg/disc in broth microdilution and disc diffusion assays, respectively. This compound is tolerated by mammalian erythrocytes and cell lines (A549 and U87) at concentrations of up to 1,000 µg/ml. When incorporated into dextran nanoparticles, the novel, optically enriched fluconazole analogue exhibited improved antifungal activity against Aspergillus fumigatus (MIC, 1.63 µg/ml). These results not only demonstrate the ability of biocatalytic approaches to yield novel, optically enriched fluconazole derivatives but also suggest that enantiomerically pure fluconazole derivatives, and their nanotized counterparts, exhibiting anti-Aspergillus activity may have reduced toxicity.
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Antifúngicos/farmacología , Aspergilosis/tratamiento farmacológico , Aspergillus fumigatus/efectos de los fármacos , Fluconazol/análogos & derivados , Fluconazol/farmacología , Células A549 , Línea Celular , Pruebas Antimicrobianas de Difusión por Disco , Fluconazol/efectos adversos , Proteínas Fúngicas/metabolismo , Humanos , Lipasa/metabolismo , Nanopartículas/químicaRESUMEN
INTRODUCTION: The recent emergence of resistance, toxicity paradigm and limited efficacy of conventional antifungal drugs necessitate the identification of de novo targets in fungal metabolism. One of the most critical physiological processes during in vivo pathogenesis is maintenance of iron homeostasis. The most life threatening opportunistic human fungal pathogens like Aspergillus, Candida and Cryptococcus exploit the siderophore mediated iron uptake mechanism either for survival, virulence, propagation or resistance to oxidative stress envisaged in vivo during infection. Areas covered: In this review, we will highlight the metabolic pathways; specifically siderophore biosynthesis, uptake and utilisation, triggered in the fungal pathogens in iron starving conditions and the various putative targets viable in these pathways to be recruited as novel therapeutic antidotes either via biosynthetic enzymes catalytic site inhibitors or as drug conjugates through trojan horse approach and further role in the development of fungal specific reliable diagnostic markers. Expert opinion: Siderophores are the weapons released by a pathogen to conquer the battle for iron acquisition. Hence, the fungal siderophore biosynthetic pathways along with their uptake and utilisation mechanisms represent an ideal target for pathogen specific, host friendly therapeutic strategy which would block the proliferation of parasite without causing any harm to the mammalian host.
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Antifúngicos/farmacología , Hierro/metabolismo , Sideróforos/metabolismo , Animales , Diseño de Fármacos , Hongos/efectos de los fármacos , Hongos/patogenicidad , Humanos , Micosis/tratamiento farmacológico , Micosis/microbiología , Sideróforos/biosíntesisRESUMEN
A de novo protein named as EAF (Escherichia antifungal protein) from the cytoplasmic pool of an Escherichia coli strain (MTCC 1652), has been purified to homogeneity using anion exchange (Q-XL Sepharose) and cation exchange (SP-Sepharose) chromatography. The MIC (minimum inhibitory concentration) values of purified protein against A. fumigatus (the major pathogenic species) were found to be comparable with standard drugs i.e. 3.90 µg/ml, 3.90 µg/ml and 1.25 µg/disc via microbroth dilution assay (MDA), percentage spore germination inhibition (PSGI) and disc diffusion assay (DDA) respectively. Toxicity results confirmed that it causes no haemolysis against human RBCs upto a concentration of 1000.0 µg/ml as compared to Amphotericin B (conventional antifungal drug) that causes hundred percent haemolysis at a concentration of 37.50 µg/ml only.The purified protein demonstrated a molecular mass of 28 kDa on SDS-PAGE which was further authenticated by MALDI-TOF. Proteomic and bioinformatics studies deciphered its significant homology (72 %) with chain A-D-ribose binding protein (cluster 2 sugar binding periplasmic proteins; sequence homologues of transcription regulatory proteins) from E. coli. Single dimensional page analysis of A. fumigatusproteins with due effect of EAF (at MIC50) revealed the inhibition of two major proteins; a heat shock protein 70-Hsp70 (68 kDa); having role in protein folding and functioning andphenylanalyl-t RNA synthetase PodG subunit protein (74 kDa); involved in growth polarity in fungi. Scanning electron microscopic studies depicted homologous results. We suggest that EAF most likely belongs to a new group of proteins with potent antifungal characteristics, negligible toxicity and targeting vital proteins of fungal metabolism.