RESUMEN
The gut microbiome plays an essential role in host immune responses, including allergic reactions. However, commensal gut microbiota is extremely sensitive to antibiotics and excessive usage can cause microbial dysbiosis. Herein, we investigated how changes in the gut microbiome induced by ampicillin affected the production of IgG1 and IgG2a antibodies in mice subsequently exposed to Anisakis pegreffii antigens. Ampicillin treatment caused a notable change in the gut microbiome as shown by changes in both alpha and beta diversity indexes. In a 1-dimensional immunoblot using Anisakis-specific anti-mouse IgG1, a 56-kDa band corresponding to an unnamed Anisakis protein was detected using mass spectrometry analysis only in ampicillin-treated mice. In the Anisakis-specific anti-mouse IgG2a-probed immunoblot, a 70-kDa band corresponding to heat shock protein 70 (HSP70) was only detected in ampicillin-treated and Anisakis-immunized mice. A 2-dimensional immunoblot against Anisakis extract with immunized mouse sera demonstrated altered spot patterns in both groups. Our results showed that ampicillin treatment altered the gut microbiome composition in mice, changing the immunization response to antigens from A. pegreffii. This research could serve as a basis for developing vaccines or allergy immunotherapies against parasitic infections.
Asunto(s)
Ampicilina , Anisakis , Microbioma Gastrointestinal , Inmunoglobulina G , Animales , Anisakis/inmunología , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/inmunología , Ampicilina/farmacología , Ratones , Inmunoglobulina G/inmunología , Inmunoglobulina G/sangre , Antígenos Helmínticos/inmunología , Femenino , Anisakiasis/inmunología , Anisakiasis/parasitología , Anticuerpos Antihelmínticos/inmunología , InmunizaciónRESUMEN
BACKGROUND: Glycopeptides for ampicillin-susceptible Enterococcus faecalis/faecium bacteremia are readily prescribed depending on the severity of the condition. However, there is limited data on the outcomes of glycopeptide use compared to ampicillin-containing regimens for ampicillin-susceptible E. faecalis/faecium bacteremia. From an antibiotic stewardship perspective, it is important to determine whether the use of glycopeptides is associated with improved clinical outcomes in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. METHODS: This retrospective cohort study was conducted at a university-affiliated hospital between January 2010 and September 2019. We collected data from patients with positive blood cultures for Enterococcus species isolates. The clinical data of patients who received ampicillin-containing regimens or glycopeptides as definitive therapy for ampicillin-susceptible E. faecalis/faecium bacteremia were reviewed. Multivariate logistic regression analysis was performed to identify risk factors for 28-day mortality. RESULTS: Ampicillin-susceptible E. faecalis/faecium accounted for 41.2% (557/1,353) of enterococcal bacteremia cases during the study period. A total of 127 patients who received ampicillin-containing regimens (N = 56) or glycopeptides (N = 71) as definitive therapy were included in the analysis. The 28-day mortality rate was higher in patients treated with glycopeptides (19.7%) than in those treated with ampicillin-containing regimens (3.6%) (p = 0.006). However, in the multivariate model, antibiotic choice was not an independent predictor of 28-day mortality (adjusted OR, 3.7; 95% CI, 0.6-23.6). CONCLUSIONS: Glycopeptide use was not associated with improved mortality in patients with ampicillin-susceptible E. faecalis/faecium bacteremia. This study provides insights to reduce the inappropriate use of glycopeptides in ampicillin-susceptible E. faecalis/faecium bacteremia treatment and promote antimicrobial stewardship.
Asunto(s)
Ampicilina , Antibacterianos , Bacteriemia , Enterococcus faecalis , Glicopéptidos , Infecciones por Bacterias Grampositivas , Sulbactam , Humanos , Estudios Retrospectivos , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Bacteriemia/mortalidad , Ampicilina/uso terapéutico , Ampicilina/farmacología , Masculino , Femenino , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Enterococcus faecalis/efectos de los fármacos , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/mortalidad , Anciano , Persona de Mediana Edad , Glicopéptidos/uso terapéutico , Glicopéptidos/farmacología , Sulbactam/uso terapéutico , Sulbactam/farmacología , Resultado del Tratamiento , Pruebas de Sensibilidad Microbiana , Anciano de 80 o más AñosRESUMEN
Depression is a global health concern affecting nearly 280 million individuals. It not only imposes a significant burden on economies and healthcare systems but also manifests complex physiological connections and consequences. Agmatine, a putative neuromodulator derived primarily from beneficial gut microbes specially Lactobacillus, has emerged as a potential therapeutic agent for mental health. The microbiota-gut-brain axis is involved in the development of depression through the peripheral nervous system, endocrine system, and immune system and may be a key factor in the effect of agmatine. Therefore, this study aimed to investigate the potential mechanism of agmatine in antibiotic-induced dysbiosis and depression-like behavior in rats, focusing on its modulation of the gut-brain axis. Depression-like behavior associated with dysbiosis was induced through a seven-day regimen of the broad-spectrum antibiotic, comprising ampicillin and metronidazole and validated through microbial, biochemical, and behavioral alterations. On day 8, antibiotic-treated rats exhibited loose fecal consistency, altered fecal microbiota, and depression-like behavior in forced swim test. Pro-inflammatory cytokines were elevated, while agmatine and monoamine levels decreased in the hippocampus and prefrontal cortex. Antibiotic administration disrupted tight junction proteins in the ileum, affecting gut architecture. Oral administration of agmatine alone or combined with probiotics significantly reversed antibiotic-induced dysbiosis, restoring gut microbiota and mitigating depression-like behaviors. This intervention also restored neuro-inflammatory markers, increased agmatine and monoamine levels, and preserved gut integrity. The study highlights the regulatory role of endogenous agmatine in the gut-brain axis in broad-spectrum antibiotic induced dysbiosis and associated depression-like behavior.
Asunto(s)
Agmatina , Conducta Animal , Eje Cerebro-Intestino , Depresión , Disbiosis , Microbioma Gastrointestinal , Animales , Agmatina/farmacología , Agmatina/uso terapéutico , Depresión/tratamiento farmacológico , Depresión/metabolismo , Masculino , Microbioma Gastrointestinal/efectos de los fármacos , Ratas , Conducta Animal/efectos de los fármacos , Eje Cerebro-Intestino/efectos de los fármacos , Antibacterianos/farmacología , Ratas Sprague-Dawley , Probióticos/farmacología , Probióticos/uso terapéutico , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Citocinas/metabolismo , Ampicilina/farmacología , Modelos Animales de EnfermedadRESUMEN
Over last years, hydrogels based on natural polymers have attracted considerable interest as materials for wound healing. Herein, hydrogel films based on kappa-carrageenan and guanidinium polyampholytes were prepared by the in situ physical cross-linking with potassium chloride and borax, respectively. The polyampholytes were obtained by a free radical copolymerization of 2,2-diallyl-1,1,3,3-tetraethylguanidinium chloride and unsaturated acids. To characterize the composite films, NMR, FTIR, SEM, TGA, XRD, element analysis and tensile test were used. Ampicillin was incorporated into the hydrogels to enhance wound healing potential. The healing-related characteristics, including swelling ratio, drug release and antimicrobial activity, were assessed. The equilibrium swelling ratios were in the range of 3.9-6.5 depending on the polyampholyte composition. According to the in vitro ampicillin release studies, 30-43 % of ampicillin was released from the hydrogels after 5 h at 37 °C and pH 7.4, with drug release being temperature and pH dependent. The ampicillin-loaded films showed a remarkable antimicrobial effect. The inhibition sizes for Escherichia coli and Staphylococcus aureus were 1.10-1.85 and 1.95-2.60 cm, respectively. Although the bi-polymeric hydrogels were thoroughly characterized, with the in vitro study of their biocidal effects carried out in this work, the in vivo drug release assessment needs to be further explored.
Asunto(s)
Antibacterianos , Carragenina , Liberación de Fármacos , Escherichia coli , Guanidina , Hidrogeles , Staphylococcus aureus , Cicatrización de Heridas , Carragenina/química , Hidrogeles/química , Hidrogeles/farmacología , Cicatrización de Heridas/efectos de los fármacos , Guanidina/química , Guanidina/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Ampicilina/farmacología , Ampicilina/química , Desinfectantes/farmacología , Desinfectantes/química , Pruebas de Sensibilidad Microbiana , Polímeros/química , Concentración de Iones de HidrógenoRESUMEN
Indole serves as a signaling molecule that could regulate different bacterial physiological processes, including antibiotic resistance through biofilm formation and drug efflux pump activity. In Escherichia coli, indole is produced through the tryptophan pathway, which involves three permeases (Mtr, AroP, and TnaB) that can transport the amino acid tryptophan. Although these permeases play distinct roles in the secretion of indole biosynthesis, their impact on multidrug resistance mediated by indole remaines unclear. This study was designed to investigate the connection between the tryptophan transport system and antibiotic resistance by constructing seven gene deletion mutants from E. coli MG1655 (wild type). Our result showed that deletion of the aroP or tnaB gene led to increased antibiotic resistance as evaluated by MICs for different antibiotics. Efflux activity test results revealed that the increased antibiotic resistance was related with the AcrAB-Tolc drug efflux pump in the mutants. The transcriptome analysis further demonstrated that decreased susceptibility to kanamycin and ampicillin in E. coli was accompanied by reduced accumulation of reactive oxygen species and decreased motility. These findings highlight the substantial influence of the tryptophan transport system on antibiotic resistance in E. coli, which is crucial for developing strategies against antibiotic resistance in bacterial infections.
Asunto(s)
Antibacterianos , Proteínas de Escherichia coli , Escherichia coli , Pruebas de Sensibilidad Microbiana , Triptófano , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Triptófano/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Antibacterianos/farmacología , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Eliminación de Gen , Farmacorresistencia Bacteriana Múltiple/genética , Transporte Biológico , Farmacorresistencia Bacteriana/genética , Especies Reactivas de Oxígeno/metabolismo , Ampicilina/farmacología , Silenciador del Gen , Kanamicina/farmacología , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Regulación Bacteriana de la Expresión Génica , Proteínas PortadorasRESUMEN
To evaluate the in vitro activity of ampicillin-sulbactam and cefoperazone-sulbactam against A. baumannii using the broth disk elution testing, a total of 150 A. baumannii isolates were collected from across China between January 2019 and January 2021, including 51 carbapenem-susceptible and 99 carbapenem-resistant isolates. Broth disk elution (BDE) and the broth microdilution (BMD) method were performed for all strains. The concentration range of the BDE was 10/10 µg/mL, 20/20 µg/mL, and 30/30 µg/mL for ampicillin-sulbactam, and 37.5/15 µg/mL, 75/30 µg/mL, 112.5/45 µg/mL, and 150/60 µg/mL for cefoperazone-sulbactam, respectively. Compared with BMD, the BDE results of ampicillin-sulbactam and cefoperazone-sulbactam showed a categorical agreement of 83.3% (125/150) and 95.3% (143/150), with minor errors of 16.7% (25/150) and 4.7% (7/150), respectively. No major error or very major errors were detected. The sensitivity differences by BDE of carbapenem-resistant A. baumannii (CRAb) to different concentrations of ampicillin-sulbactam showed statistically significant (p < 0.017), while those to cefoperazone-sulbactam at 37.5/15 µg/mL, 75/30 µg/mL, and 112.5/45 µg/mL were significant (p < 0.008). However, no significant difference in sensitivity was observed between 112.5/45 µg/mL and 150/60 µg/mL (p > 0.008). In conclusion, the BDE is a reliable and convenient method to detect the in vitro activity of cefoperazone-sulbactam against A. baumannii, and the results could serve as a clinical reference value when deciding whether or not to use high-dose sulbactam for the treatment of A. baumannii infections.
Asunto(s)
Acinetobacter baumannii , Ampicilina , Antibacterianos , Cefoperazona , Sulbactam , Acinetobacter baumannii/efectos de los fármacos , Sulbactam/farmacología , Cefoperazona/farmacología , Ampicilina/farmacología , Antibacterianos/farmacología , Humanos , Infecciones por Acinetobacter/microbiología , Pruebas de Sensibilidad Microbiana , China , Pruebas Antimicrobianas de Difusión por Disco/métodosRESUMEN
Researchers continuously focused on the fabrication of innovative drug delivery systems to prevent microbial infections while minimizing systemic side effects. Among these, pH-sensitive antibiotic release systems based on bio-based materials have gained great attention due to their ability to precisely modulate drug kinetics and enhance therapeutic efficacy. Herein, pH-sensitive alginate/hyaluronic acid/gelatin ternary blended films were fabricated for the controlled release of ampicillin. Swelling capacity, hydrolytic degradation profile, pH reversibility and in vitro ampicillin release behavior of produced films were investigated in both simulated gastric (pH 1.2) and intestinal (pH 7.4) environments. The cumulative release amount of ampicillin at pH 1.2 (61.0 ± 1.07 mg drug/g polymer) was greater than that of at pH 7.4 (43.0 ± 1.05 mg drug/g polymer) proved that release behavior of ampicillin for produced films is pH-dependent. Based on the fitted release data, best fit was found as the first-order kinetic model with the highest R2 values of 0.966 and 0.962 for both pH conditions. According to Korsmeyer-Peppas model, drug release mechanism is also controlled by case II-transport. Furthermore, produced films demonstrated excellent cytocompatibility. All results revealed that obtained films could be a promising drug carrier to traditional targeting systems for site-specific, pH-sensitive ampicillin delivery in both gastric and intestine.
Asunto(s)
Alginatos , Ampicilina , Portadores de Fármacos , Liberación de Fármacos , Gelatina , Ácido Hialurónico , Ampicilina/química , Ampicilina/farmacología , Ácido Hialurónico/química , Concentración de Iones de Hidrógeno , Gelatina/química , Portadores de Fármacos/química , Cinética , Alginatos/química , Antibacterianos/química , Antibacterianos/farmacología , AnimalesRESUMEN
BACKGROUND: Aminopenicillins are recommended agents for non-invasive Haemophilus influenzae infections. One of the mechanisms of resistance to ß-lactams is the alteration of the transpeptidase region of penicillin binding protein 3 (PBP3) which is caused by mutations in the ftsI gene. It was shown that exposure to beta-lactams has a stimulating effect on increase of prevalence of H. influenzae strains with the non-enzymatic mechanism of resistance. OBJECTIVES: The aim of our study was to compare the mutational potential of ampicillin and cefuroxime in H. influenzae strains, determination of minimum inhibitory concentration and the evolution of mutations over time, focusing on amino acid substitutions in PBP3. METHODS: 30 days of serial passaging of strains in liquid broth containing increasing concentrations of ampicillin or cefuroxime was followed by whole-genome sequencing. RESULTS: On average, cefuroxime increased the minimum inhibitory concentration more than ampicillin. The minimum inhibitory concentration was increased by a maximum of 32 fold. Substitutions in the PBP3 started to appear after 15 days of passaging. In PBP3, cefuroxime caused different substitutions than ampicillin. CONCLUSIONS: Our experiment observed differences in mutation selection by ampicillin and cefuroxime. Selection pressure of antibiotics in vitro generated substitutions that do not occur in clinical strains in the Czech Republic.
Asunto(s)
Sustitución de Aminoácidos , Ampicilina , Antibacterianos , Cefuroxima , Haemophilus influenzae , Pruebas de Sensibilidad Microbiana , Mutación , Proteínas de Unión a las Penicilinas , Cefuroxima/farmacología , Ampicilina/farmacología , Haemophilus influenzae/genética , Haemophilus influenzae/efectos de los fármacos , Proteínas de Unión a las Penicilinas/genética , Proteínas de Unión a las Penicilinas/metabolismo , Antibacterianos/farmacología , Humanos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Infecciones por Haemophilus/microbiología , Secuenciación Completa del Genoma , Evolución Molecular , Selección Genética , Pase SeriadoRESUMEN
Metallo-ß-lactamases (MßLs) hydrolyze and inactivate ß-lactam antibiotics, are a pivotal mechanism conferring resistance against bacterial infections. SMB-1, a novel B3 subclass of MßLs from Serratia marcescens could deactivate almost all ß-lactam antibiotics including ampicillin (AMP), which has posed a serious threat to public health. To illuminate the mechanism of recognition and interaction between SMB-1 and AMP, various fluorescence spectroscopy techniques and molecular dynamics simulation were employed. The results of quenching spectroscopy unraveled that AMP could make SMB-1 fluorescence quenching that mechanism was the static quenching; the synchronous and three-dimensional fluorescence spectra validated that the microenvironment and conformation of SMB-1 were altered after interaction with AMP. The molecular dynamics results demonstrated that the whole AMP enters the binding pocket of SMB-1, even though with a relatively bulky R1 side chain. Loop1 and loop2 in SMB-1 undergo significant fluctuations, and α2 (71-73) and local α5 (186-188) were turned into random coils, promoting zinc ion exposure consistent with circular dichroism spectroscopy results. The binding between them was driven by a combination of enthalpy and entropy changes, which was dominated by electrostatic force in agreement with the fluorescence observations. The present study brings structural insights and solid foundations for the design of new substrates for ß-lactamases and the development of effective antibiotics that are resistant to superbugs.
Asunto(s)
Ampicilina , Simulación de Dinámica Molecular , Serratia marcescens , Espectrometría de Fluorescencia , beta-Lactamasas , beta-Lactamasas/química , beta-Lactamasas/metabolismo , Ampicilina/química , Ampicilina/metabolismo , Ampicilina/farmacología , Serratia marcescens/enzimología , Unión Proteica , Sitios de Unión , Antibacterianos/química , Antibacterianos/farmacología , Antibacterianos/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismoRESUMEN
Antibiotic exposure is associated with resistant bacterial colonization, but this relationship can be obscured in community settings owing to horizontal bacterial transmission and broad distributions. Locality-level exposure estimates considering inhabitants' length of stay, exposure history, and exposure conditions of areas nearby could clarify these relationships. We used prescription data filled during 2010-2015 for 23 antibiotic types for members of georeferenced households in a population-based infectious disease surveillance platform. For each antibiotic and locality, we generated exposure estimates, expressed in defined daily doses (DDD) per 1000 inhabitant days of observation (IDO). We also estimated relevant environmental parameters, such as the distance of each locality to water, sanitation, and other amenities. We used data on ampicillin, ceftazidime, and trimethoprim-and-sulfamethoxazole resistant Escherichia coli colonization from stool cultures of asymptomatic individuals in randomly selected households. We tested exposure-colonization associations using permutation analysis of variance and logistic generalized linear mixed-effect models. Overall, exposure was highest for trimethoprim-sulfamethoxazole (1.8 DDD per 1000 IDO), followed by amoxicillin (0.7 DDD per 1000 IDO). Of 1,386 unique household samples from 195 locations tested between September 2015 and January 2016, 90%, 85% and 4% were colonized with E. coli resistant to trimethoprim and sulfamethoxazole, ampicillin, and ceftazidime, respectively. Ceftazidime-resistant E. coli colonization was common in areas with increased trimethoprim-sulfamethoxazole, cloxacillin, and erythromycin exposure. No association with any of the physical environmental variables was observed. We did not detect relationships between distribution patterns of ampicillin or trimethoprim-and-sulfamethoxazole resistant E. coli colonization and the risk factors assessed. Appropriate temporal and spatial scaling of raw antibiotic exposure data to account for evolution and ecological contexts of antibiotic resistance could clarify exposure-colonization relationships in community settings and inform community stewardship program.
Asunto(s)
Antibacterianos , Infecciones por Escherichia coli , Escherichia coli , Humanos , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Antibacterianos/farmacología , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/tratamiento farmacológico , Femenino , Masculino , Adulto , Niño , Adolescente , Preescolar , Persona de Mediana Edad , Combinación Trimetoprim y Sulfametoxazol/farmacología , Ceftazidima/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Adulto Joven , Ampicilina/farmacología , LactanteRESUMEN
BACKGROUND: Sulbactam dosing for Acinetobacter baumannii infections has not been standardized due to limited available pharmacokinetics/pharmacodynamics (PK/PD) data. Herein, we report a comprehensive PK/PD analysis of ampicillin-sulbactam against A. baumannii pneumonia. METHODS: Twenty-one A. baumannii clinical isolates were tested in the neutropenic murine pneumonia model. For dose-ranging studies, groups of mice were administered escalating doses of ampicillin-sulbactam. Changes in log10cfu/lungs relative to 0 h were assessed. Dose-fractionation studies were performed. Estimates of the percentage of of time during which the unbound plasma sulbactam concentrations exceeded the MIC (%fTâ>âMIC) required for different efficacy endpoints were calculated. The probabilities of target attainment (PTA) for the 1-log kill plasma targets were estimated following clinically utilized sulbactam regimens. RESULTS: Dose-fractionation studies demonstrated time-dependent kill. Isolates resistant to both sulbactam and meropenem required three times the exposures to achieve 1-log kill; median [IQR] %fTâ>âMIC of 60.37% [51.6-66.8] compared with other phenotypes (21.17 [16.0-32.9] %fTâ>âMIC). Sulbactam standard dose (1 g q6h, 0.5 h infusion) provided >90% PTA up to MIC of 4 mg/L. Sulbactam 3 g q8h, 4 h inf provided greater PTA for isolates with sulbactam-intermediate susceptibility (8 mg/L, 100% versus 86% following the standard dose). Despite the higher exposure following 3 g q8h, 4 h inf, PTA was ≤57% among sulbactam-resistant/meropenem-resistant isolates. CONCLUSION: Sulbactam standard dose is a valuable regimen across sulbactam-susceptible isolates while the high-dose extended-infusion provides additional benefit against sulbactam-intermediate isolates. Given that most of the sulbactam-resistant A. baumannii isolates are meropenem-resistant, high-dose prolonged-infusion regimens are not expected to be effective as monotherapy against infections due to these isolates.
Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Ampicilina , Antibacterianos , Pruebas de Sensibilidad Microbiana , Sulbactam , Acinetobacter baumannii/efectos de los fármacos , Sulbactam/farmacocinética , Sulbactam/administración & dosificación , Sulbactam/farmacología , Sulbactam/uso terapéutico , Antibacterianos/farmacocinética , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Animales , Ampicilina/farmacocinética , Ampicilina/administración & dosificación , Ampicilina/farmacología , Ratones , Femenino , Modelos Animales de Enfermedad , Neumonía Bacteriana/tratamiento farmacológico , Neumonía Bacteriana/microbiología , HumanosRESUMEN
This study evaluates the antibacterial effectiveness of Origanum vulgare hydroethanolic extract, both independently and in combination with antibiotics, against Escherichia coli strains associated with avian colibacillosis-a significant concern for the poultry industry due to the rise of antibiotic-resistant E. coli. The urgent demand for new treatments is addressed by analyzing the extract's phytochemical makeup via High-Performance Liquid Chromatography (HPLC), which identified sixteen phenolic compounds. Antibacterial activity was determined through agar diffusion and the measurement of minimum inhibitory and bactericidal concentrations (MIC and MBC), showing moderate efficacy (MIC: 3.9 to 7.8 mg/mL, MBC: 31.2 to 62.4 mg/mL). Combining the extract with antibiotics like ampicillin and tetracycline amplified antibacterial activity, indicating a synergistic effect and highlighting the importance of combinatory treatments against resistant strains. Further analysis revealed the extract's mechanisms of action include disrupting bacterial cell membrane integrity and inhibiting ATPase/H+ proton pumps, essential for bacterial survival. Moreover, the extract effectively inhibited and eradicated biofilms, crucial for preventing bacterial colonization. Regarding cytotoxicity, the extract showed no hemolytic effect at 1 to 9 mg/mL concentrations. These results suggest Origanum vulgare extract, particularly when used with antibiotics, offers a promising strategy for managing avian colibacillosis, providing both direct antibacterial benefits and moderating antibiotic resistance, thus potentially reducing the economic impact of the disease on the poultry industry.
Asunto(s)
Antibacterianos , Biopelículas , Sinergismo Farmacológico , Escherichia coli , Pruebas de Sensibilidad Microbiana , Origanum , Extractos Vegetales , Origanum/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Animales , Biopelículas/efectos de los fármacos , Enfermedades de las Aves de Corral/tratamiento farmacológico , Enfermedades de las Aves de Corral/microbiología , Infecciones por Escherichia coli/tratamiento farmacológico , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Pollos , Ampicilina/farmacología , Tetraciclina/farmacologíaRESUMEN
Background: The healing of burn wounds is a complicated physiological process that involves several stages, including haemostasis, inflammation, proliferation, and remodelling to rebuild the skin and subcutaneous tissue integrity. Recent advancements in nanomaterials, especially nanofibers, have opened a new way for efficient healing of wounds due to burning or other injuries. Methods: This study aims to develop and characterize collagen-decorated, bilayered electrospun nanofibrous mats composed of PVP and PVA loaded with Resveratrol (RSV) and Ampicillin (AMP) to accelerate burn wound healing and tissue repair. Results: Nanofibers with smooth surfaces and web-like structures with diameters ranging from 200 to 400 nm were successfully produced by electrospinning. These fibres exhibited excellent in vitro properties, including the ability to absorb wound exudates and undergo biodegradation over a two-week period. Additionally, these nanofibers demonstrated sustained and controlled release of encapsulated Resveratrol (RSV) and Ampicillin (AMP) through in vitro release studies. The zone of inhibition (ZOI) of PVP-PVA-RSV-AMP nanofibers against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was found 31±0.09 mm and 12±0.03, respectively, which was significantly higher as compared to positive control. Similarly, the biofilm study confirmed the significant reduction in the formation of biofilms in nanofiber-treated group against both S. aureus and E. coli. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis proved the encapsulation of RSV and AMP successfully into nanofibers and their compatibility. Haemolysis assay (%) showed no significant haemolysis (less than 5%) in nanofiber-treated groups, confirmed their cytocompatibility with red blood cells (RBCs). Cell viability assay and cell adhesion on HaCaT cells showed increased cell proliferation, indicating its biocompatibility as well as non-toxic properties. Results of the in-vivo experiments on a burn wound model demonstrated potential burn wound healing in rats confirmed by H&E-stained images and also improved the collagen synthesis in nanofibers-treated groups evidenced by Masson-trichrome staining. The ELISA assay clearly indicated the efficient downregulation of TNF-alpha and IL-6 inflammatory biomarkers after treatment with nanofibers on day 10. Conclusion: The RSV and AMP-loaded nanofiber mats, developed in this study, expedite burn wound healing through their multifaceted approach.
Asunto(s)
Ampicilina , Quemaduras , Colágeno , Nanofibras , Resveratrol , Cicatrización de Heridas , Animales , Humanos , Masculino , Ratas , Ampicilina/administración & dosificación , Ampicilina/farmacocinética , Ampicilina/farmacología , Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Quemaduras/tratamiento farmacológico , Colágeno/química , Escherichia coli/efectos de los fármacos , Nanofibras/química , Alcohol Polivinílico/química , Povidona/química , Resveratrol/administración & dosificación , Resveratrol/farmacocinética , Resveratrol/farmacología , Staphylococcus aureus/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Microbial colonization and development of infections in wounds is a sign of chronicity. The prevailing approach to manage and treat these wounds involves dressings. However, these often fail in effectively addressing infections, as they struggle to both absorb exudates and maintain optimal local moisture. The system here presented was conceptualized with a three-layer design: the outer layer made of a fibrous polycaprolactone (PCL) film, to act as a barrier for preventing microorganisms and impurities from reaching the wound; the intermediate layer formed of a sodium alginate (SA) hydrogel loaded with ampicillin (Amp) for fighting infections; and the inner layer comprised of a fibrous film of PCL and polyethylene glycol (PEG) for facilitating cell recognition and preventing wound adhesion. Thermal evaluations, degradation, wettability and release behavior testing confirmed the system resistance overtime. The sandwich demonstrated the capability for absorbing exudates (≈70 %) and exhibited a controlled release of Amp for up to 24 h. Antimicrobial testing was performed against Staphylococcus aureus and Escherichia coli, as representatives of Gram-positive and Gram-negative bacteria: >99 % elimination of bacteria. Cell cytotoxicity assessments showed high cytocompatibility levels, confirming the safety of the proposed sandwich system. Adhesion assays confirmed the system ease of detaching without mechanical effort (0.37 N). Data established the efficiency of the sandwich-like system, suggesting promising applications in infected wound care.
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Alginatos , Antibacterianos , Escherichia coli , Poliésteres , Staphylococcus aureus , Infección de Heridas , Alginatos/química , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antibacterianos/química , Antibacterianos/administración & dosificación , Poliésteres/química , Ampicilina/farmacología , Ampicilina/uso terapéutico , Ampicilina/química , Humanos , Hidrogeles/química , Polietilenglicoles/química , Animales , Vendajes , Pruebas de Sensibilidad Microbiana , Ratones , Cicatrización de Heridas/efectos de los fármacosRESUMEN
BACKGROUND: Lactobacillus plantarum has been found to play a significant role in maintaining the balance of intestinal flora in the human gut. However, it is sensitive to commonly used antibiotics and is often incidentally killed during treatment. We attempted to identify a means to protect L. plantarum ATCC14917 from the metabolic changes caused by two commonly used antibiotics, ampicillin, and doxycycline. We examined the metabolic changes under ampicillin and doxycycline treatment and assessed the protective effects of adding key exogenous metabolites. RESULTS: Using metabolomics, we found that under the stress of ampicillin or doxycycline, L. plantarum ATCC14917 exhibited reduced metabolic activity, with purine metabolism a key metabolic pathway involved in this change. We then screened the key biomarkers in this metabolic pathway, guanine and adenosine diphosphate (ADP). The exogenous addition of each of these two metabolites significantly reduced the lethality of ampicillin and doxycycline on L. plantarum ATCC14917. Because purine metabolism is closely related to the production of reactive oxygen species (ROS), the results showed that the addition of guanine or ADP reduced intracellular ROS levels in L. plantarum ATCC14917. Moreover, the killing effects of ampicillin and doxycycline on L. plantarum ATCC14917 were restored by the addition of a ROS accelerator in the presence of guanine or ADP. CONCLUSIONS: The metabolic changes of L. plantarum ATCC14917 under antibiotic treatments were determined. Moreover, the metabolome information that was elucidated can be used to help L. plantarum cope with adverse stress, which will help probiotics become less vulnerable to antibiotics during clinical treatment.
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Ampicilina , Antibacterianos , Doxiciclina , Lactobacillus plantarum , Metabolómica , Lactobacillus plantarum/metabolismo , Lactobacillus plantarum/efectos de los fármacos , Antibacterianos/farmacología , Ampicilina/farmacología , Doxiciclina/farmacología , Especies Reactivas de Oxígeno/metabolismo , Purinas/metabolismo , Estrés Fisiológico/efectos de los fármacos , Redes y Vías Metabólicas/efectos de los fármacos , Adenosina Difosfato/metabolismo , HumanosRESUMEN
The incidence of beta-lactam resistance among clinical isolates is a major health concern. A key method to study the emergence of antibiotic resistance is adaptive laboratory evolution. However, in the case of the beta-lactam ampicillin, bacteria evolved in laboratory settings do not recapitulate clinical-like resistance levels, hindering efforts to identify major evolutionary paths and their dependency on genetic background. Here, we used the Microbial Evolution and Growth Arena (MEGA) plate to select ampicillin-resistant Escherichia coli mutants with varying degrees of resistance. Whole-genome sequencing of resistant isolates revealed that ampicillin resistance was acquired via a combination of single-point mutations and amplification of the gene encoding beta-lactamase AmpC. However, blocking AmpC-mediated resistance revealed latent adaptive pathways: strains deleted for ampC were able to adapt through combinations of changes in genes involved in multidrug resistance encoding efflux pumps, transcriptional regulators, and porins. Our results reveal that combinations of distinct genetic mutations, accessible at large population sizes, can drive high-level resistance to ampicillin even independently of beta-lactamases.
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Resistencia a la Ampicilina , Ampicilina , Antibacterianos , Proteínas Bacterianas , Escherichia coli , beta-Lactamasas , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Resistencia a la Ampicilina/genética , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Ampicilina/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del Genoma , Evolución Molecular , MutaciónRESUMEN
Bacterial communities are highly complex, with interaction networks dictating ecosystem function. Bacterial interactions are constrained by the spatial organization of these microbial communities, yet studying the spatial organization of microbial communities at the single-cell level has been technically challenging. Here, we use the recently developed high-phylogenetic-resolution microbiota mapping by fluorescence in situ hybridization technology to image the gut microbiota at the species and single-cell level. We simultaneously image 63 different bacterial species to spatially characterize the perturbation and recovery of the gut microbiota to ampicillin and vancomycin in the cecum and distal colon of mice. To decipher the biology in this complex imaging data, we developed an analytical framework to characterize the spatial changes of the gut microbiota to a perturbation. The three-tiered analytical approach includes image-level diversity, pairwise colocalization analysis, and hypothesis-driven neighborhood analysis. Through this workflow, we identify biogeographic and antibiotic-based differences in the spatial organization of the gut microbiota. We demonstrate that the cecal microbiota has increased micrometer-scale diversity than the colon at baseline and recovers better from perturbation. Also, we identify potential foundation and keystone species that have high baseline neighborhood richness and that are associated with recovery from antibiotics. Through this workflow, we add a spatial layer to the characterization of bacterial communities and progress toward a better understanding of bacterial interactions leading to improved microbiome modulation strategies. IMPORTANCE: Antibiotics have broad off-target effects on the gut microbiome. When the microbial community is unable to recover from antibiotics, it can lead to increased susceptibility to gastrointestinal infections and increased risk of immunological and metabolic diseases. In this study, we work to better understand how the gut microbiota recovers from antibiotics by employing a recent technology to image the entire bacterial community at once. Through this approach, we characterize the spatial changes in the gut microbiota after treatment with model antibiotics in both the cecum and colon of mice. We find antibiotic- and biogeographic-dependent spatial changes between bacterial species and that many of these spatial colocalizations do not recover to baseline levels even 35 days after antibiotic administration.
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Antibacterianos , Bacterias , Ciego , Colon , Microbioma Gastrointestinal , Hibridación Fluorescente in Situ , Vancomicina , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Antibacterianos/farmacología , Ratones , Bacterias/clasificación , Bacterias/genética , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Ciego/microbiología , Vancomicina/farmacología , Colon/microbiología , Ampicilina/farmacología , Ratones Endogámicos C57BL , FilogeniaRESUMEN
Non-heritable, phenotypic drug resistance toward antibiotics challenges antibiotic therapies. Characteristics of such phenotypic resistance have implications for the evolution of heritable resistance. Diverse forms of phenotypic resistance have been described, but phenotypic resistance characteristics remain less explored than genetic resistance. Here, we add novel combinations of single-cell characteristics of phenotypic resistant E. coli cells and compare those to characteristics of susceptible cells of the parental population by exposure to different levels of recurrent ampicillin antibiotic. Contrasting expectations, we did not find commonly described characteristics of phenotypic resistant cells that arrest growth or near growth. We find that under ampicillin exposure, phenotypic resistant cells reduced their growth rate by about 50% compared to growth rates prior to antibiotic exposure. The growth reduction is a delayed alteration to antibiotic exposure, suggesting an induced response and not a stochastic switch or caused by a predetermined state as frequently described. Phenotypic resistant cells exhibiting constant slowed growth survived best under ampicillin exposure and, contrary to expectations, not only fast-growing cells suffered high mortality triggered by ampicillin but also growth-arrested cells. Our findings support diverse modes of phenotypic resistance, and we revealed resistant cell characteristics that have been associated with enhanced genetically fixed resistance evolution, which supports claims of an underappreciated role of phenotypic resistant cells toward genetic resistance evolution. A better understanding of phenotypic resistance will benefit combatting genetic resistance by developing and engulfing effective anti-phenotypic resistance strategies. IMPORTANCE: Antibiotic resistance is a major challenge for modern medicine. Aside from genetic resistance to antibiotics, phenotypic resistance that is not heritable might play a crucial role for the evolution of antibiotic resistance. Using a highly controlled microfluidic system, we characterize single cells under recurrent exposure to antibiotics. Fluctuating antibiotic exposure is likely experienced under common antibiotic therapies. These phenotypic resistant cell characteristics differ from previously described phenotypic resistance, highlighting the diversity of modes of resistance. The phenotypic characteristics of resistant cells we identify also imply that such cells might provide a stepping stone toward genetic resistance, thereby causing treatment failure.
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Ampicilina , Antibacterianos , Farmacorresistencia Bacteriana , Escherichia coli , Fenotipo , Análisis de la Célula Individual , Ampicilina/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Bacteriana/efectos de los fármacos , Pruebas de Sensibilidad MicrobianaRESUMEN
The emergence of multidrug-resistant bacteria poses a significant threat to human health, necessitating a comprehensive understanding of their underlying mechanisms. Uropathogenic Escherichia coli (UPEC), the primary causative agent of urinary tract infections, is frequently associated with multidrug resistance and recurrent infections. To elucidate the mechanism of resistance of UPEC to beta-lactam antibiotics, we generated ampicillin-resistant UPEC strains through continuous exposure to low and high levels of ampicillin in the laboratory, referred to as Low AmpR and High AmpR, respectively. Whole-genome sequencing revealed that both Low and High AmpR strains contained mutations in the marR, acrR, and envZ genes. The High AmpR strain exhibited a single additional mutation in the nlpD gene. Using protein modeling and qRT-PCR analyses, we validated the contributions of each mutation in the identified genes to antibiotic resistance in the AmpR strains, including a decrease in membrane permeability, increased expression of multidrug efflux pump, and inhibition of cell lysis. Furthermore, the AmpR strain does not decrease the bacterial burden in the mouse bladder even after continuous antibiotic treatment in vivo, implicating the increasing difficulty in treating host infections caused by the AmpR strain. Interestingly, ampicillin-induced mutations also result in multidrug resistance in UPEC, suggesting a common mechanism by which bacteria acquire cross-resistance to other classes of antibiotics.
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Ampicilina , Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Infecciones por Escherichia coli , Mutación , Infecciones Urinarias , Escherichia coli Uropatógena , Escherichia coli Uropatógena/genética , Escherichia coli Uropatógena/efectos de los fármacos , Animales , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones Urinarias/microbiología , Infecciones por Escherichia coli/microbiología , Ratones , Antibacterianos/farmacología , Ampicilina/farmacología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Femenino , Humanos , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del GenomaRESUMEN
We aimed to investigate ampicillin (AMP) mechanisms in microbiota-gut-brain axis. We evaluated its effect on two gut and brain regions and behavioral performances. We administred AMP (1 g/l) to BALB/c mice for 21 days. Then, we analyzed body weigth change, stool consistency scoring, gut length, intestinal microbiota composition, nitric oxide synthase 2 (NOS2) expression and tissue integrity. We subsequently evaluated NOS2, GFAP, CD68 and NFL cerebral expression and spatial memory.Interestingly, our data showed gut microbiota disruption, NOS2 upregulation and tissue damage, associated to cerebral NOS2, GFAP, CD68 and NFL over-expression and behavioral alteration. Antiobiotic therapy should be prescribed with great caution.