RESUMEN
The biofilm-induced "relatively immune-compromised zone" creates an immunosuppressive microenvironment that is a significant contributor to refractory infections in orthopedic endophytes. Consequently, the manipulation of immune cells to co-inhibit or co-activate signaling represents a crucial strategy for the management of biofilm. This study reports the incorporation of Mn2+ into mesoporous dopamine nanoparticles (Mnp) containing the stimulator of interferon genes (STING) pathway activator cGAMP (Mncp), and outer wrapping by M1-like macrophage cell membrane (m-Mncp). The cell membrane enhances the material's targeting ability for biofilm, allowing it to accumulate locally at the infectious focus. Furthermore, m-Mncp mechanically disrupts the biofilm through photothermal therapy and induces antigen exposure through photodynamic therapy-generated reactive oxygen species (ROS). Importantly, the modulation of immunosuppression and immune activation results in the augmentation of antigen-presenting cells (APCs) and the commencement of antigen presentation, thereby inducing biofilm-specific humoral immunity and memory responses. Additionally, this approach effectively suppresses the activation of myeloid-derived suppressor cells (MDSCs) while simultaneously boosting the activity of T cells. Our study showcases the efficacy of utilizing m-Mncp immunotherapy in conjunction with photothermal and photodynamic therapy to effectively mitigate residual and recurrent infections following the extraction of infected implants. As such, this research presents a viable alternative to traditional antibiotic treatments for biofilm that are challenging to manage.
Asunto(s)
Biopelículas , Indoles , Proteínas de la Membrana , Polímeros , Biopelículas/efectos de los fármacos , Polímeros/química , Animales , Indoles/química , Indoles/farmacología , Ratones , Proteínas de la Membrana/metabolismo , Nanopartículas/química , Fotoquimioterapia/métodos , Porosidad , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Femenino , Transducción de Señal/efectos de los fármacos , Terapia Fototérmica , Células Supresoras de Origen Mieloide/metabolismo , Células Supresoras de Origen Mieloide/efectos de los fármacos , Ratones Endogámicos C57BLRESUMEN
Chlorogenic acid (CGA) is a well-known plant secondary metabolite exhibiting multiple physiological functions. The present study focused on screening for synergistic antibacterial combinations containing CGA. The combination of CGA and p-coumaric acid (pCA) exhibited remarkably enhanced antibacterial activity compared to that when administering the treatment only. Scanning electron microscopy revealed that a low-dose combination treatment could disrupt the Shigella dysenteriae cell membrane. A comprehensive analysis using nucleic acid and protein leakage assay, conductivity measurements, and biofilm formation inhibition experiments revealed that co-treatment increased the cell permeability and inhibited the biofilm formation substantially. Further, the polyacrylamide protein- and agarose gel-electrophoresis indicated that the proteins and DNA genome of Shigella dysenteriae severely degraded. Finally, the synergistic bactericidal effect was established for fresh-cut tomato preservation. This study demonstrates the remarkable potential of strategically selecting antibacterial agents with maximum synergistic effect and minimum dosage exhibiting excellent antibacterial activity in food preservation.
Asunto(s)
Antibacterianos , Ácido Clorogénico , Ácidos Cumáricos , Sinergismo Farmacológico , Shigella dysenteriae , Antibacterianos/farmacología , Antibacterianos/química , Ácidos Cumáricos/farmacología , Ácidos Cumáricos/química , Ácido Clorogénico/farmacología , Ácido Clorogénico/química , Shigella dysenteriae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Biopelículas/efectos de los fármacos , Propionatos/farmacología , Solanum lycopersicum/química , Solanum lycopersicum/microbiología , Conservación de Alimentos/métodosRESUMEN
Biofilm-associated infections (BAIs) continue to pose a major challenge in the medical field. Nanomedicine, in particular, promises significant advances in combating BAIs through the introduction of a variety of nanomaterials and nano-antimicrobial strategies. However, studies to date have primarily focused on the removal of the bacterial biofilm and neglect the subsequent post-biofilm therapeutic measures for BAIs, rendering pure anti-biofilm strategies insufficient for the holistic recovery of affected patients. Herein, we construct an emerging dual-functional composite nanosheet (SiHx@Ga) that responds to pHs fluctuation in the biofilm microenvironment to enable a sequential therapy of BAIs. In the acidic environment of biofilm, SiHx@Ga employs the self-sensitized photothermal Trojan horse strategy to effectively impair the reactive oxygen species (ROS) defense system while triggering oxidative stress and lipid peroxidation of bacteria, engendering potent antibacterial and anti-biofilm effects. Surprisingly, in the post-treatment phase, SiHx@Ga adsorbs free pathogenic nucleic acids released after biofilm destruction, generates hydrogen with ROS-scavenging and promotes macrophage polarization to the M2 type, effectively mitigating damaging inflammatory burst and promoting tissue healing. This well-orchestrated strategy provides a sequential therapy of BAIs by utilizing microenvironmental variations, offering a conceptual paradigm shift in the field of nanomedicine anti-infectives.
Asunto(s)
Antibacterianos , Biopelículas , Galio , Especies Reactivas de Oxígeno , Biopelículas/efectos de los fármacos , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Galio/química , Galio/farmacología , Ratones , Portadores de Fármacos/química , Células RAW 264.7 , Humanos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiologíaRESUMEN
OBJECTIVES: The mannose phosphotransferase system (Man-PTS) plays crucial roles in the adaptive metabolic activity of Enterococcus faecalis (E. faecalis) in adverse environments. The aim of this study was to evaluate the role of Man-PTS in the alkaline resistance of E. faecalis against calcium hydroxide (CH) and the effect of metformin (Met) on the alkaline resistance of E. faecalis to CH. MATERIALS AND METHODS: The regulatory role of Man-PTS EII in the alkaline resistance of E. faecalis was firstly investigated using a wild-type highly alkaline-resistant E. faecalis XS 003, standard ATCC 29212 and Man-PTS EIID gene deficient (â³mptD) and overexpressing (+mptD) strains of E. faecalis. RNA sequencing of Met-treated E. faecalis was performed to further validate the effect of Met on Man-PTS. The effect of Met on CH resistance of E. faecalis was verified by evaluating the survival, membrane potential and permeability, intracellular pH and ATP, and the expression of Man-PTS EII and membrane transporter-related genes of E. faecalis. The effect of Met on the ability of CH to remove E. faecalis biofilm on the dentin surface was also tested. The in vivo therapeutic effect of Met plus CH (CHM) was further investigated in a rat apical periodontitis model induced by E. faecalis XS 003. RESULTS: Man-PTS EII significantly promoted the survival ability of E. faecalis in CH and enhanced its resistance to CH. The inhibition of Man-PTS EII by Met resulted in reduced alkaline resistance of E. faecalis in the presence of CH, while also enhancing the antimicrobial properties of CH against E. faecalis biofilm on dentin. Additionally, Met plus CH showed the synergistically promoted intra-canal E. faecalis infection control and healing of periapical lesion in rats. CONCLUSIONS: Met could significantly reduce the alkaline resistance of E. faecalis against CH through the modulation of Man-PTS EII, and improved the antibacterial effect of CH against E. faecalis infection both in vitro and in vivo. CLINICAL RELEVANCE: Met could significantly enhance the ability of CH to control E. faecalis infection through reducing the alkaline resistance of E. faecalis.
Asunto(s)
Hidróxido de Calcio , Enterococcus faecalis , Metformina , Enterococcus faecalis/efectos de los fármacos , Animales , Ratas , Metformina/farmacología , Hidróxido de Calcio/farmacología , Biopelículas/efectos de los fármacos , Técnicas In Vitro , Modelos Animales de Enfermedad , Farmacorresistencia Bacteriana , Masculino , Ratas Sprague-Dawley , Antibacterianos/farmacología , Irrigantes del Conducto Radicular/farmacologíaRESUMEN
Normal skin is the first line of defense in the human body. A burn injury makes the skin susceptible to bacterial infection, thereby delaying wound healing and ultimately leading to sepsis. The chances of biofilm formation are high in burn wounds due to the presence of avascular necrotic tissue. The most common pathogen to cause burn infection and biofilm is Pseudomonas aeruginosa. The purpose of this study was to create a microemulsion (ME) formulation for topical application to treat bacterial burn infection. In the present study, tea tree oil was used as the oil phase, Tween 80 and transcutol were used as surfactants, and water served as the aqueous phase. Pseudo ternary phase diagrams were used to determine the design space. The ranges of components as suggested by the design were chosen, optimization of the microemulsion was performed, and in vitro drug release was assessed. Based on the characterization studies performed, it was found that the microemulsion were formulated properly, and the particle size obtained was within the desired microemulsion range of 10 to 300 nm. The I release study showed that the microemulsion followed an immediate release profile. The formulation was further tested based on its ability to inhibit biofilm formation and bacterial growth. The prepared microemulsion was capable of inhibiting biofilm formation.
Asunto(s)
Antibacterianos , Biopelículas , Quemaduras , Sistemas de Liberación de Medicamentos , Emulsiones , Pseudomonas aeruginosa , Biopelículas/efectos de los fármacos , Quemaduras/tratamiento farmacológico , Quemaduras/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Tamaño de la Partícula , Liberación de Fármacos , Tensoactivos/química , Polisorbatos/química , Aceite de Árbol de Té/administración & dosificación , Aceite de Árbol de Té/química , Aceite de Árbol de Té/farmacología , Química Farmacéutica/métodos , HumanosRESUMEN
Management of urinary tract infections (UTI) is a highly challenging process due to the biofilm-forming ability of human-pathogenic bacteria. Here, we designed to fabricate an effective nanogel with a combination of chitosan bio-polymer and nalidixic acid to prevent biofilm-forming bacterial pathogens. Chitosan-coated nalidixic acid nanogel (NA@CS) exhibits outstanding inhibition potential against bacterial strains. In vitro, anti-bacterial analysis methods (well diffusion, colony-forming assay, and anti-biofilm assay) were performed to study the bacterial inhibition potential of prepared nanogel, which reveals that NA@CS nanogel have greater inhibition potential against selected pathogens. The combination of nalidixic acid with chitosan biopolymer decreases the virulence and pathogenicity of biofilm-forming pathogens due to their ability to membrane phospholipids penetration. Furthermore, the fabricated NA@CS nanogel showed reliable in vitro bio-compatibility on L929 fibroblast cells and in vivo compatibility with Artemia salina animal model. Overall, the results demonstrate that NA@CS nanogel could be an effective therapeutic for treating urinary tract infections and urine bladder wound healing.
Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Ácido Nalidíxico , Nanogeles , Infecciones Urinarias , Infecciones Urinarias/microbiología , Infecciones Urinarias/prevención & control , Infecciones Urinarias/tratamiento farmacológico , Quitosano/química , Quitosano/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Animales , Nanogeles/química , Ácido Nalidíxico/farmacología , Biopelículas/efectos de los fármacos , Ratones , Línea Celular , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Humanos , Artemia/efectos de los fármacos , Artemia/microbiologíaRESUMEN
BACKGROUND: Staphylococcus aureus is an infectious bacterium that is frequently found in healthcare settings and the community. This study aimed to prepare rutin-loaded chitosan nanoparticles (Rut-CS NPs) and assess their antibacterial activity against pathogenic strains of S. aureus. RESULTS: The synthesized Rut-CS NPs exhibited an amorphous morphology with a size ranging from 160 to 240 nm and a zeta potential of 37.3 mV. Rut-CS NPs demonstrated significant antibacterial activity against S. aureus strains. Following exposure to Rut-CS NPs, the production of staphyloxanthin pigment decreased by 43.31-89.63%, leading to increased susceptibility of S. aureus to hydrogen peroxide. Additionally, visual inspection of cell morphology indicated changes in membrane integrity and permeability upon Rut-CS NPs exposure, leading to a substantial increase (107.07-191.08%) in cytoplasmic DNA leakage in the strains. Furthermore, ½ MIC of Rut-CS NPs effectively inhibited the biofilm formation (22.5-37.5%) and hemolytic activity (69-82.59%) in the S. aureus strains. CONCLUSIONS: Our study showcases that Rut-CS NPs can serve as a novel treatment agent to combat S. aureus infections by altering cell morphology and inhibiting virulence factors of S. aureus.
Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Pruebas de Sensibilidad Microbiana , Nanopartículas , Rutina , Staphylococcus aureus , Xantófilas , Staphylococcus aureus/efectos de los fármacos , Quitosano/farmacología , Quitosano/química , Rutina/farmacología , Rutina/química , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química , Biopelículas/efectos de los fármacos , Xantófilas/farmacología , Xantófilas/química , Hemólisis/efectos de los fármacos , Factores de Virulencia , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Humanos , Peróxido de Hidrógeno/farmacologíaRESUMEN
The primary aim of this study was to investigate the impact of treatment with low-temperature plasma (LTP) for varying exposure durations on a multispecies cariogenic biofilm comprising C. albicans, L. casei, and S. mutans, as well as on single-species biofilms of L. casei and C. albicans, cultured on hydroxyapatite discs. Biofilms were treated with LTP-argon at a 10 mm distance for 30 s, 60 s, and 120 s. Chlorhexidine solution (0.12%) and NaCl (0.89%) were used as positive (PC) and negative controls (NC), respectively. Argon flow only was also used as gas flow control (F). Colony-forming units (CFU) recovery and confocal laser scanning microscopy (CLSM) were used to analyze biofilm viability. LTP starting at 30 s of application significantly reduced the viability of multispecies biofilms by more than 2 log10 in all treated samples (p < 0.0001). For single-species biofilms, L. casei showed a significant reduction compared to PC and NC of over 1 log10 at all exposure times (p < 0.0001). In the case of C. albicans biofilms, LTP treatment compared to PC and NC resulted in a significant decrease in bacterial counts when applied for 60 and 120 s (1.55 and 1.90 log10 CFU/mL, respectively) (p < 0.0001). A significant effect (p ≤ 0.05) of LTP in single-species biofilms was observed to start at 60 s of LTP application compared to F, suggesting a time-dependent effect of LTP for the single-species biofilms of C. albicans and L. casei. LTP is a potential mechanism in treating dental caries by being an effective anti-biofilm therapy of both single and multispecies cariogenic biofilms.
Asunto(s)
Biopelículas , Candida albicans , Gases em Plasma , Streptococcus mutans , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Gases em Plasma/farmacología , Candida albicans/fisiología , Candida albicans/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/fisiología , Caries Dental/microbiología , Caries Dental/terapia , Lacticaseibacillus casei/fisiología , Humanos , Viabilidad Microbiana/efectos de los fármacos , Microscopía Confocal , FríoRESUMEN
BACKGROUND: Nosocomial infections are a global problem in hospitals all around the world. It is considered a major health problem, especially in developing countries. The increase in the patient's stay in hospitals has increased the mortality rate, and consequently, the costs drastically increase. The main purpose of using disinfectants in the hospital environment is to reduce the risk of nosocomial infections. Ethylene diamine tetra acetic acid (EDTA) causes lysis and increases susceptibility to antimicrobial agents in the planktonic form of bacteria. This substance affects the permeability of the outer membrane of bacteria. It also prevents the formation of biofilms by bacteria. MATERIALS AND METHODS: In the current study, 120 isolates of Acinetobacter baumannii (A. baumannii) were confirmed by phenotypic and genotypic methods. Antibiogram was performed and then the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of isolates against 5% sodium hypochlorite, ethanol %70, sayasept-HP 2%, chlorhexidine 2%, dettol 4/8% were evaluated. In addition, the disinfectant effect was re-evaluated with the mixture of EDTA solution. All isolates were examined for biofilm presence by crystal violet staining method in triplicates and repeated three times for each strain. Also for all isolates detection of efflux pump genes (Qac-E, qacE-Δ1, SUG-E) by PCR technique was done. RESULTS: Antibiogram results of A. baumannii showed that 6.7% were Multi-drug-resistant (MDR), and 89.2% were Extensively drug-resistant (XDR) isolates. The highest effect of disinfectants was related to 5% sodium hypochlorite, and the least effect was 70% ethanol. EDTA increases the efficacy of selected disinfectants significantly. The highest prevalence of the efflux pump genes was related to SUG-E (95%) and Qac-E (91.7%), and, the qacE-Δ1 gene with 12.5%. The biofilm production rate was 91.3% among all isolates. CONCLUSION: The best and safest way to disinfect hospital floors and surfaces is to choose the right disinfectants, and learn how to use them properly. In this study, a mixture of disinfectants and EDTA had a significant effect on bactericidal activity. it was found that improper use of disinfectants, especially the use of sub-inhibitory dilutions, increases the resistance of bacteria to disinfectants.
Asunto(s)
Acinetobacter baumannii , Biopelículas , Desinfectantes , Genotipo , Pruebas de Sensibilidad Microbiana , Fenotipo , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/genética , Acinetobacter baumannii/fisiología , Acinetobacter baumannii/aislamiento & purificación , Desinfectantes/farmacología , Humanos , Irán , Ácido Edético/farmacología , Farmacorresistencia Bacteriana/genética , Antibacterianos/farmacología , Infecciones por Acinetobacter/microbiología , Hipoclorito de Sodio/farmacología , Infección Hospitalaria/microbiología , Clorhexidina/farmacologíaRESUMEN
This study was to investigate the antibacterial effects and metabolites derived from bifidobacterial fermentation of an exopolysaccharide EPS-LM produced by a medicinal fungus Cordyceps sinensis, Cs-HK1. EPS-LM was a partially purified polysaccharide fraction which was mainly composed of Man, Glc and Gal at 7.31:12.95:1.00 mol ratio with a maximum molecular weight of 360 kDa. After fermentation of EPS-LM in two bifidobacterial cultures, B. breve and B. longum, the culture digesta showed significant antibacterial activities, inhibiting the proliferation and biofilm formation of Escherichia coli. Based on untargeted metabolomic profiling of the digesta, the levels of short chain fatty acids, carboxylic acids, benzenoids and their derivatives were all increased significantly (p < 0.01), which probably contributed to the enhanced antibacterial activity by EPS-LM. Since EPS-LM was only slightly consumed for the bifidobacterial growth, it mainly stimulated the biosynthesis of bioactive metabolites in the bifidobacterial cells. The results also suggested that EPS-LM polysaccharide may have a regulatory function on the bifidobacterial metabolism leading to production of antibacterial metabolites, which may be of significance for further exploration.
Asunto(s)
Antibacterianos , Cordyceps , Escherichia coli , Fermentación , Polisacáridos Bacterianos , Antibacterianos/farmacología , Antibacterianos/química , Cordyceps/metabolismo , Cordyceps/química , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Polisacáridos Bacterianos/farmacología , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/metabolismo , Biopelículas/efectos de los fármacos , Polisacáridos Fúngicos/farmacología , Polisacáridos Fúngicos/química , Pruebas de Sensibilidad MicrobianaRESUMEN
Biofilm is a common problem associated with human health. Pathogenicity and increase in resistance of bacteria require urgent development of effective ways for the treatment of bacterial diseases. Different strategies have been developed for the treatment of bacterial infections among which nanoparticles have shown greater prospects in battling with infections. Biofilms are resistant microbial colonies that possess resistance and, hence, cannot be killed by conventional drugs. Nanoparticles offer new avenues for treating biofilm-related infections involving multi-drug resistant organisms. They possess great antibiofilm properties, disrupting cell architecture and preventing colony formation. Green-synthesised nanoparticles are more effective and less toxic to human cells than commercially available or chemically synthesised antibiofilm nanoparticles. This review summarises the antibiofilm efficiency of plant-mediated nanoparticles and knowledge about biofilm inhibition.
Asunto(s)
Antibacterianos , Biopelículas , Nanopartículas , Biopelículas/efectos de los fármacos , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Humanos , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad MicrobianaRESUMEN
A 15-month-old spayed female greater Swiss mountain dog was brought to our clinic because of relapsing episodes of urinary tract infection, present since her adoption at 2 mo of age. A diagnosis of chronic bacterial cystitis associated with an invasive, biofilm-forming uropathogenic Escherichia coli was made with bladder-wall histology and fluorescent in situ hybridization analysis. Local treatment with EDTA-tromethamine (EDTA-Tris) infusions along with parenteral cefquinome and prophylactic measures (Type-A proanthocyanidins and probiotics) coincided with clinical and bacterial remission. The dog has been free of clinical signs of urinary tract infection for >4 y. Biofilm-forming uropathogenic E. coli can cause chronic, recurrent cystitis due to low antibiotic efficacy and should be considered in cases of recurrent cystitis in dogs, especially in the absence of identified predisposing factors. This case report describes the diagnostic and therapeutic options that were used to manage a case of this type. Key clinical message: Fluorescent in situ hybridization analysis may be considered in the diagnosis of chronic bacterial cystitis in dogs, and intravesical instillations of EDTA-Tris may be helpful in managing such cases.
Traitement adjuvant intravésical avec de l'EDTA-trométhamine chez un chien présentant une cystite récurrente à Escherichia coli formant des biofilmsUne chienne grand bouvier suisse stérilisée de 15 mois nous a été présentée pour des épisodes d'infection du tractus urinaire récidivants depuis son adoption à l'âge de 2 mois. Une cystite bactérienne chronique associée à un Escherichia coli uropathogène formant des biofilms a été identifiée par l'examen histologique de la paroi vésicale et par hybridation in situ fluorescente. Des instillations intravésicales d'EDTA et trométhamine (EDTA-Tris) en complément d'une antibiothérapie parentérale de courte durée (cefquinome) et de mesures prophylactiques (proanthocyanidines de type A et probiotiques) ont permis une guérison clinique et bactériologique de la cystite pendant plus de 4 ans. Les infections par Escherichia coli formant des biofilms peuvent causer des cystites chroniques récurrentes dues à une faible efficacité des antibiotiques et doivent être incluses dans le diagnostic différentiel des cystites récurrentes chez le chien, particulièrement en l'absence d'autre facteur prédisposant. Ce rapport propose des stratégies diagnostiques et thérapeutiques ayant permis la prise en charge d'un de ces cas.Message clinique clé :L'analyse par hybridation in situ fluorescente peut être envisagé dans le diagnostic de cystite bactérienne chronique chez les chiens, et l'instillation intravésicale d'EDTA-Tris peut être utile dans la gestion de tels cas.(Traduit par les auteurs).
Asunto(s)
Antibacterianos , Biopelículas , Cistitis , Enfermedades de los Perros , Ácido Edético , Infecciones por Escherichia coli , Perros , Animales , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/microbiología , Femenino , Cistitis/veterinaria , Cistitis/tratamiento farmacológico , Cistitis/microbiología , Ácido Edético/uso terapéutico , Ácido Edético/administración & dosificación , Biopelículas/efectos de los fármacos , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/tratamiento farmacológico , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Administración Intravesical , Escherichia coli/efectos de los fármacos , RecurrenciaRESUMEN
Candida auris has emerged as a significant healthcare-associated pathogen due to its multidrug-resistant nature. Ongoing constraints in the discovery and provision of new antifungals create an urgent imperative to design effective remedies to this pressing global blight. Herein, we screened a chemical library and identified aryl-carbohydrazide analogs with potent activity against both C. auris and the most prevalent human fungal pathogen, C. albicans. SPB00525 [N'-(2,6-dichlorophenyl)-5-nitro-furan-2-carbohydrazide] exhibited potent activity against different strains that were resistant to standard antifungals. Using drug-induced haploinsufficient profiling, transcriptomics and metabolomic analysis, we uncovered that Ole1, a Δ(9) fatty acid desaturase, is the likely target of SPB00525. An analog of the latter, HTS06170 [N'-(2,6-dichlorophenyl)-4-methyl-1,2,3-thiadiazole-5-carbohydrazide], had a superior antifungal activity against both C. auris and C. albicans. Both SPB00525 and HTS06170 act as antivirulence agents and inhibited the invasive hyphal growth and biofilm formation of C. albicans. SPB00525 and HTS06170 attenuated fungal damage to human enterocytes and ameliorate the survival of Galleria mellonella larvae used as systemic candidiasis model. These data suggest that inhibiting fungal Δ(9) fatty acid desaturase activity represents a potential therapeutic approach for treating fungal infection caused by the superbug C. auris and the most prevalent human fungal pathogen, C. albicans.
Asunto(s)
Antifúngicos , Candida auris , Candidiasis , Pruebas de Sensibilidad Microbiana , Antifúngicos/farmacología , Animales , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , Candida auris/efectos de los fármacos , Candida auris/genética , Ácido Graso Desaturasas/metabolismo , Ácido Graso Desaturasas/genética , Ácido Graso Desaturasas/antagonistas & inhibidores , Candida albicans/efectos de los fármacos , Candida albicans/enzimología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Humanos , Inhibidores Enzimáticos/farmacología , Mariposas Nocturnas/microbiología , Mariposas Nocturnas/efectos de los fármacos , Metabolómica , Larva/microbiología , Larva/efectos de los fármacos , Modelos Animales de Enfermedad , Hidrazinas/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Perfilación de la Expresión GénicaRESUMEN
Cationic biocides (CBs), which include quaternary ammonium compounds (QACs), are employed to mitigate the spread of infectious bacteria, but resistance to such surface disinfectants is rising. CB exposure can have profound phenotypic implications that extend beyond allowing microorganisms to persist on surfaces. Pseudomonas aeruginosa is a deadly bacterial pathogen that is intrinsically tolerant to a wide variety of antimicrobials and is commonly spread in healthcare settings. In this study, we pursued resistance selection assays to the QAC benzalkonium chloride and quaternary phosphonium compound P6P-10,10 to assess the phenotypic effects of CB exposure in P. aeruginosa PAO1 and four genetically diverse, drug-resistant clinical isolates. In particular, we sought to examine how CB exposure affects defensive strategies and the virulence-associated "offensive" strategies in P. aeruginosa. We demonstrated that development of resistance to BAC is associated with increased production of virulence-associated pigments and alginate as well as pellicle formation. In an in vivo infection model, CB-resistant PAO1 exhibited a decreased level of virulence compared to wild type, potentially due to an observed fitness cost in these strains. Taken together, these results illustrate the significant consequence CB resistance exerts on the virulence-associated phenotypes of P. aeruginosa.
Asunto(s)
Desinfectantes , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Factores de Virulencia , Pseudomonas aeruginosa/patogenicidad , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Desinfectantes/farmacología , Virulencia , Factores de Virulencia/genética , Infecciones por Pseudomonas/microbiología , Animales , Compuestos de Benzalconio/farmacología , Farmacorresistencia Bacteriana , Ratones , Compuestos de Amonio Cuaternario/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Adaptación Fisiológica , Cationes/farmacologíaRESUMEN
Methicillin-resistant Staphylococcus aureus (MRSA) is an opportunistic pathogen that can cause severe bacterial pneumonia. Amygdalin is the main active pharmaceutical ingredient of bitter almond, which has broad-spectrum antibacterial, anti-inflammatory, anti-oxidation and immunomodulatory effects. It is also the main ingredient of Yinhua Pinggan granule, which is commonly used to moisten the lung and relieve cough. However, little is known about the effects of amygdalin on MRSA. In this study, we found that amygdalin exhibited good antimicrobial activity in vitro against MRSA. Amygdalin has a protective effect on MRSA infected cells, and the effect is better when combined with levofloxacin. It also can reduce the adhesion and invasion of MRSA to cells. Amygdalin has anti-inflammatory and antioxidant effects, which can significantly reduce the increase of inflammatory factors and the production of ROS caused by infection. The protective mechanism of amygdalin on cells may be related to inhibiting the expression of NLRP3, ASC and IL-1ß pyroptosis pathways. Taken together, our study suggests that amygdalin exerts antibacterial effects by affecting biofilm formation, the expression of virulence factors, and drug resistance genes. Amygdalin combined with levofloxacin has a protective effect on A549 cells infected with MRSA, and the mechanism may be related to the inhibition of inflammatory response, oxidative damage and pyroptosis.
Asunto(s)
Amigdalina , Antibacterianos , Inflamación , Staphylococcus aureus Resistente a Meticilina , Estrés Oxidativo , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Amigdalina/farmacología , Humanos , Estrés Oxidativo/efectos de los fármacos , Células A549 , Antibacterianos/farmacología , Inflamación/tratamiento farmacológico , Inflamación/patología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/microbiología , Células Epiteliales/metabolismo , Pulmón/microbiología , Pulmón/patología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Biopelículas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Levofloxacino/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiologíaRESUMEN
The increase of antibiotic-resistant bacteria has become a global health emergency and the need to explore alternative therapeutic options arises. Phage therapy uses bacteriophages to target specific bacterial strains. Phages are highly specific and can target resistant bacteria. Currently, research in this regard is focused on ensuring reliability and safety to bring this tool into clinical practice. The first step is to conduct comprehensive preclinical research. In this work, we present two novel bacteriophages vB_Kpn_F13 and vB_Kpn_F14 isolated against clinical carbapenem-resistant Klebsiella pneumoniae strains obtained from hospital sewage. Multiple studies in vitro were conducted, such as sequencing, electron microscopy, stability, host range infectivity, planktonic effect and biofilm inhibition in order to discover their ability to be used against carbapenem-resistant K. pneumoniae pathogens causing difficult-to-treat infections.
Asunto(s)
Bacteriófagos , Biopelículas , Enterobacteriaceae Resistentes a los Carbapenémicos , Carbapenémicos , Infecciones por Klebsiella , Klebsiella pneumoniae , Terapia de Fagos , Klebsiella pneumoniae/virología , Klebsiella pneumoniae/efectos de los fármacos , Bacteriófagos/aislamiento & purificación , Bacteriófagos/fisiología , Bacteriófagos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Enterobacteriaceae Resistentes a los Carbapenémicos/virología , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/terapia , Carbapenémicos/farmacología , Biopelículas/crecimiento & desarrollo , Biopelículas/efectos de los fármacos , Humanos , Especificidad del Huésped , Aguas del Alcantarillado/virología , Aguas del Alcantarillado/microbiología , Antibacterianos/farmacología , Genoma Viral , Pruebas de Sensibilidad MicrobianaRESUMEN
Background: In the face of increasing antifungal resistance among Candida albicans biofilms, this study explores the efficacy of a combined treatment using Kangbainian lotion (KBN) and miconazole nitrate (MN) to address this challenge. Methods: Using UPLC-Q-TOF/MS Analysis for Identification of Active Compounds in KBN Lotion; FICI for synergy evaluation, XTT and ROS assays for biofilm viability and oxidative stress, fluorescence and confocal laser scanning microscopy (CLSM) for structural and viability analysis, and real-time fluorescence for gene expression. Conclusion: Our study indicates that the combined application of KBN and MN somewhat impacts the structural integrity of Candida albicans biofilms and affects the expression of several key genes involved in biofilm formation, including ALS1, ALS3, HWP1, HSP90, and CSH1. These preliminary findings suggest that there may be a synergistic effect between KBN and MN, potentially influencing not only the structural aspects of fungal biofilms but also involving the modulation of genetic pathways during their formation.
Asunto(s)
Antifúngicos , Biopelículas , Candida albicans , Farmacorresistencia Fúngica , Sinergismo Farmacológico , Miconazol , Pruebas de Sensibilidad Microbiana , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Antifúngicos/farmacología , Miconazol/farmacología , Especies Reactivas de Oxígeno/metabolismo , Viabilidad Microbiana/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , HumanosRESUMEN
Candida albicans is an opportunistic fungal pathogen that can cause systemic infections in immunocompromised individuals. Morphological transition and biofilm formation are major virulence factors of C. albicans. Moreover, biofilm enhances resistance to antifungal agents. Therefore, it is urgent to identify new and effective compounds to target the biofilm of C. albicans. In the present study, the antifungal activities of equol against C. albicans were investigated. In vitro, the microdilution analysis and spot assay result showed that equol exhibited potent inhibitory activities against C. albicans. Further investigations confirmed that the antifungal effects of equol involved interference with the transition from yeast to hypha and biofilm formation of C. albicans. In addition, transcriptome sequencing and reverse transcription-quantitative PCR (qRT-PCR) analysis showed that equol significantly downregulated the expression of several genes in the Ras1-cAMP-PKA pathway related to hyphae and biofilm formation and significantly upregulated the expression of the negative transcriptional repressors RFG1 and TUP1. Moreover, equol effectively reduced the production of cAMP, a key messenger in the Ras1-cAMP-PKA pathway, while supplementation with cAMP partly rescued the equol-induced defects in hyphal development. Furthermore, in a mouse model of systemic candidiasis (SC), equol treatment significantly decreased the fungal burden (liver, kidneys, and lung) in mice and local tissue damage, while enhancing the production of interleukin-10 (IL-10). Together, these findings confirm that equol is a potentially effective agent for treatment of SC.
Asunto(s)
Antifúngicos , Biopelículas , Candida albicans , Candidiasis , Equol , Candida albicans/efectos de los fármacos , Candida albicans/genética , Animales , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Ratones , Candidiasis/microbiología , Candidiasis/tratamiento farmacológico , Equol/farmacología , Femenino , Modelos Animales de Enfermedad , Pruebas de Sensibilidad Microbiana , Hifa/efectos de los fármacos , Hifa/crecimiento & desarrollo , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Ratones Endogámicos BALB C , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismoRESUMEN
Pathogen-host competition for manganese and intricate immunostimulatory pathways severely attenuates the efficacy of antibacterial immunotherapy against biofilm infections associated with orthopaedic implants. Herein, we introduce a spatiotemporal sono-metalloimmunotherapy (SMIT) strategy aimed at efficient biofilm ablation by custom design of ingenious biomimetic metal-organic framework (PCN-224)-coated MnO2-hydrangea nanoparticles (MnPM) as a metalloantibiotic. Upon reaching the acidic H2O2-enriched biofilm microenvironment, MnPM can convert abundant H2O2 into oxygen, which is conducive to significantly enhancing the efficacy of ultrasound (US)-triggered sonodynamic therapy (SDT), thereby exposing bacteria-associated antigens (BAAs). Moreover, MnPM disrupts bacterial homeostasis, further killing more bacteria. Then, the Mn ions released from the degraded MnO2 can recharge immune cells to enhance the cGAS-STING signaling pathway sensing of BAAs, further boosting the immune response and suppressing biofilm growth via biofilm-specific T cell responses. Following US withdrawal, the sustained oxygenation promotes the survival and migration of fibroblasts, stimulates the expression of angiogenic growth factors and angiogenesis, and neutralizes excessive inflammation. Our findings highlight that MnPM may act as an immune costimulatory metalloantibiotic to regulate the cGAS-STING signaling pathway, presenting a promising alternative to antibiotics for orthopaedic biofilm infection treatment and pro-tissue repair.
Asunto(s)
Biopelículas , Compuestos de Manganeso , Óxidos , Oxígeno , Biopelículas/efectos de los fármacos , Animales , Ratones , Compuestos de Manganeso/química , Compuestos de Manganeso/farmacología , Oxígeno/metabolismo , Óxidos/farmacología , Óxidos/química , Antibacterianos/farmacología , Peróxido de Hidrógeno/metabolismo , Inmunoterapia/métodos , Humanos , Terapia por Ultrasonido/métodos , Nanopartículas/química , Transducción de Señal/efectos de los fármacos , Antígenos Bacterianos/inmunología , Staphylococcus aureus/efectos de los fármacos , FemeninoRESUMEN
The quorum sensing (QS) system mediated by the abaI gene in Acinetobacter baumannii is crucial for various physiological and pathogenic processes. In this study, we constructed a stable markerless abaI knockout mutant (ΔabaI) strain using a pEXKm5-based allele replacement method to investigate the impact of abaI on A. baumannii. Proteomic analysis revealed significant alterations in protein expression between the wild type (WT) and ΔabaI mutant strains, particularly in proteins associated with membrane structure, antibiotic resistance, and virulence. Notably, the downregulation of key outer membrane proteins such as SurA, OmpA, OmpW, and BamA suggests potential vulnerabilities in outer membrane integrity, which correlate with structural abnormalities in the ΔabaI mutant strain, including irregular cell shapes and compromised membrane integrity, observed by scanning and transmission electron microscopy. Furthermore, diminished expression of regulatory proteins such as OmpR and GacA-GacS highlights the broader regulatory networks affected by abaI deletion. Functional assays revealed impaired biofilm formation and surface-associated motility in the mutant strain, indicative of altered colonization capabilities. Interestingly, the mutant showed a complex antibiotic susceptibility profile. While it demonstrated increased susceptibility to membrane-targeting antibiotics, its response to beta-lactams was more nuanced. Despite increased expression of metallo-beta-lactamase (MBL) superfamily proteins and DcaP-like protein, the mutant unexpectedly showed lower MICs for carbapenems (imipenem and meropenem) compared to the wild-type strain. This suggests that abaI deletion affects antibiotic susceptibility through multiple, potentially competing mechanisms. Further investigation is needed to fully elucidate the interplay between quorum sensing, antibiotic resistance genes, and overall antibiotic susceptibility in A. baumannii. Our findings underscore the multifaceted role of the abaI gene in modulating various cellular processes and highlight its significance in A. baumannii physiology, pathogenesis, and antibiotic resistance. Targeting the abaI QS system may offer novel therapeutic strategies for this clinically significant pathogen.