scholarly journals In-Vitro Study of the Synergistic Effect of an Enzyme Cocktail and Antibiotics against Biofilms in a Prosthetic Joint Infection Model

Author(s):  
Hervé Poilvache ◽  
Albert Ruiz-Sorribas ◽  
Olivier Cornu ◽  
Françoise Van Bambeke

Prosthetic Joint Infections (PJI) are frequent complications of arthroplasties. Their treatment is made complex by the rapid formation of bacterial biofilms, limiting the effectiveness of antibiotic therapy. In this study, we explore the effect of a tri-enzymatic cocktail (TEC) consisting of an endo-1,4-β-d-glucanase, a β-1,6-hexosaminidase, and an RNA/DNA nonspecific endonuclease combined with antibiotics of different classes against biofilms of S. aureus, S. epidermidis, and E. coli grown on Ti6Al4V substrates. Biofilms were grown in TSB with 10g/L glucose and 20g/L NaCl (TGN). Mature biofilms were assigned to a control group or treated with the TEC for 30 min, then either analyzed or reincubated for 24h in TGN or TGN with antibiotics. The cytotoxicity of the TEC was assayed against MG-63 osteoblasts, primary murine fibroblasts, and J-774 macrophages using the LDH release test. The TEC dispersed 80.3 to 95.2% of the biofilms’ biomass after 30 min. The reincubation of the treated biofilms with antibiotics resulted in a synergistic reduction of the total culturable bacterial count (CFU) compared to biofilms treated with antibiotics alone in the three tested species (additional reduction from 2 to more than 3 log10 CFU). No toxicity of the TEC was observed against the tested cell lines after a 24 h of incubation. The combination of pretreatment with TEC followed by a 24 h of incubation with antibiotics had a synergistic effect against biofilms of S. aureus, S. epidermidis, and E. coli. Further studies should assess the potential of the TEC as an adjuvant therapy in in vivo models of PJI.

2014 ◽  
Vol 58 (11) ◽  
pp. 6496-6500 ◽  
Author(s):  
Laure Gatin ◽  
Azzam Saleh-Mghir ◽  
Jason Tasse ◽  
Idir Ghout ◽  
Frédéric Laurent ◽  
...  

ABSTRACTCeftaroline (CPT), the active metabolite of the prodrug ceftaroline-fosamil (CPT-F), demonstratesin vitrobactericidal activity against methicillin-resistantStaphylococcus aureus(MRSA) and is effective in rabbit models of difficult-to-treat MRSA endocarditis and acute osteomyelitis. However, itsin vivoefficacy in a prosthetic joint infection (PJI) model is unknown. Using a MRSA-infected knee PJI model in rabbits, the efficacies of CPT-F or vancomycin (VAN) alone and combined with rifampin (RIF) were compared. After each partial knee replacement with a silicone implant that fit into the tibial intramedullary canal was performed, 5 × 107MRSA CFU (MICs of 0.38, 0.006, and 1 mg/liter for CPT, RIF, and VAN, respectively) was injected into the knee. Infected animals were randomly assigned to receive no treatment (controls) or CPT-F (60 mg/kg of body weight intramuscularly [i.m.]), VAN (60 mg/kg i.m.), CPT-F plus RIF (10 mg/kg i.m.), or VAN plus RIF starting 7 days postinoculation and lasting for 7 days. Surviving bacteria in crushed tibias were counted 3 days after ending treatment. Although thein vivomean log10CFU/g of CPT-treated (3.0 ± 0.9,n= 12) and VAN-treated (3.5 ± 1.1,n= 12) crushed bones was significantly lower than those of controls (5.6 ± 1.1,n= 14) (P< 0.001), neither treatment fully sterilized the bones (3/12 were sterile with each treatment). The mean log10CFU/g values for the antibiotics in combination with RIF were 1.9 ± 0.5 (12/14 were sterile) for CPT-F and 1.9 ± 0.5 (12/14 were sterile) for VAN. In this MRSA PJI model, the efficacies of CPT-F and VAN did not differ; thus, CPT appears to be a promising antimicrobial agent for the treatment of MRSA PJIs.


2021 ◽  
Vol 8 (9) ◽  
pp. 197
Author(s):  
Gustav Bruer ◽  
Daria Gödecke ◽  
Manfred Kietzmann ◽  
Jessica Meißner

The effect of florfenicol against Escherichia coli (E. coli) was investigated in vivo to confirm results of an in vitro study of Bruer et al. (2019), which has shown positive effects of various antibacterial agents in combination with the antihistamine mepyramine (MEP). Therefore, pigs were treated in three different settings: An untreated control group, 10 mg/kg florfenicol (FFC) and 10 mg/kg FFC in combination with 20 mg/kg MEP. E. coli were isolated from faecal samples and analyzed in growth quantity and resistance to FFC. The FFC medication induced an increased number of resistant E. coli strains isolated from faecal samples. The number of colonies detected after cultivation of animal samples treated with 10 mg/kg FFC was higher than the number of colonies after treatment with 10 mg/kg FFC in combination with of FFC and MEP. Furthermore, the effect of both compounds was examined on bacterial susceptibility of Pasteurella multocida in vitro, where the combination of FFC with MEP resulted in a diminished minimum inhibitory concentration. We confirmed the development of bacterial resistance in the intestine as non-target tissue caused by the use of the antibacterial agent florfenicol. Moreover, the combination of FFC with an antihistamine like MEP offers a possibility to enhance the efficacy of an antibacterial treatment and modifies the effect on gut microbiota.


Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 656
Author(s):  
Luis Buzón-Martín ◽  
I. Zollner-Schwetz ◽  
Selma Tobudic ◽  
Emilia Cercenado ◽  
Jaime Lora-Tamayo

Dalbavancin (DAL) is a lipoglycopeptide with bactericidal activity against a very wide range of Gram-positive microorganisms. It also has unique pharmacokinetic properties, namely a prolonged half-life (around 181 h), which allows a convenient weekly dosing regimen, and good diffusion in bone tissue. These features have led to off-label use of dalbavancin in the setting of bone and joint infection, including prosthetic joint infections (PJI). In this narrative review, we go over the pharmacokinetic and pharmacodynamic characteristics of DAL, along with published in vitro and in vivo experimental models evaluating its activity against biofilm-embedded bacteria. We also examine published experience of osteoarticular infection with special attention to DAL and PJI.


2020 ◽  
Vol 10 ◽  
Author(s):  
John Jairo Aguilera-Correa ◽  
Amaya Garcia-Casas ◽  
Aranzazu Mediero ◽  
David Romera ◽  
Francisca Mulero ◽  
...  

2005 ◽  
Vol 49 (6) ◽  
pp. 2343-2351 ◽  
Author(s):  
Patricia Komp Lindgren ◽  
Linda L. Marcusson ◽  
Dorthe Sandvang ◽  
Niels Frimodt-Møller ◽  
Diarmaid Hughes

ABSTRACT Resistance to fluoroquinolones in urinary tract infection (UTIs) caused by Escherichia coli is associated with multiple mutations, typically those that alter DNA gyrase and DNA topoisomerase IV and those that regulate AcrAB-TolC-mediated efflux. We asked whether a fitness cost is associated with the accumulation of these multiple mutations. Mutants of the susceptible E. coli UTI isolate Nu14 were selected through three to five successive steps with norfloxacin. Each selection was performed with the MIC of the selected strain. After each selection the MIC was measured; and the regions of gyrA, gyrB, parC, and parE, previously associated with resistance mutations, and all of marOR and acrR were sequenced. The first selection step yielded mutations in gyrA, gyrB, and marOR. Subsequent selection steps yielded mutations in gyrA, parE, and marOR but not in gyrB, parC, or acrR. Resistance-associated mutations were identified in almost all isolates after selection steps 1 and 2 but in less than 50% of isolates after subsequent selection steps. Selected strains were competed in vitro, in urine, and in a mouse UTI infection model against the starting strain, Nu14. First-step mutations were not associated with significant fitness costs. However, the accumulation of three or more resistance-associated mutations was usually associated with a large reduction in biological fitness, both in vitro and in vivo. Interestingly, in some lineages a partial restoration of fitness was associated with the accumulation of additional mutations in late selection steps. We suggest that the relative biological costs of multiple mutations may influence the evolution of E. coli strains that develop resistance to fluoroquinolones.


2019 ◽  
Vol 131 (6) ◽  
pp. 1301-1315 ◽  
Author(s):  
Thomas J. Gerber ◽  
Valérie C. O. Fehr ◽  
Suellen D. S. Oliveira ◽  
Guochang Hu ◽  
Randal Dull ◽  
...  

Abstract Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New Background Sevoflurane with its antiinflammatory properties has shown to decrease mortality in animal models of sepsis. However, the underlying mechanism of its beneficial effect in this inflammatory scenario remains poorly understood. Macrophages play an important role in the early stage of sepsis as they are tasked with eliminating invading microbes and also attracting other immune cells by the release of proinflammatory cytokines such as interleukin-1β, interleukin-6, and tumor necrosis factor-α. Thus, the authors hypothesized that sevoflurane mitigates the proinflammatory response of macrophages, while maintaining their bactericidal properties. Methods Murine bone marrow–derived macrophages were stimulated in vitro with lipopolysaccharide in the presence and absence of 2% sevoflurane. Expression of cytokines and inducible NO synthase as well as uptake of fluorescently labeled Escherichia coli (E. coli) were measured. The in vivo endotoxemia model consisted of an intraperitoneal lipopolysaccharide injection after anesthesia with either ketamine and xylazine or 4% sevoflurane. Male mice (n = 6 per group) were observed for a total of 20 h. During the last 30 min fluorescently labeled E. coli were intraperitoneally injected. Peritoneal cells were extracted by peritoneal lavage and inducible NO synthase expression as well as E. coli uptake by peritoneal macrophages was determined using flow cytometry. Results In vitro, sevoflurane enhanced lipopolysaccharide-induced inducible NO synthase expression after 8 h by 466% and increased macrophage uptake of fluorescently labeled E. coli by 70% compared with vehicle-treated controls. Inhibiting inducible NO synthase expression pharmacologically abolished this increase in bacteria uptake. In vivo, inducible NO synthase expression was increased by 669% and phagocytosis of E. coli by 49% compared with the control group. Conclusions Sevoflurane enhances phagocytosis of bacteria by lipopolysaccharide-challenged macrophages in vitro and in vivo via an inducible NO synthase–dependent mechanism. Thus, sevoflurane potentiates bactericidal and antiinflammatory host-defense mechanisms in endotoxemia.


2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S429-S429 ◽  
Author(s):  
Denis Daigle ◽  
Salvador Vernacchio ◽  
Luigi Xerri ◽  
Daniel Pevear

Abstract Background VNRX-5133 is a cyclic boronate β-lactamase inhibitor (BLI) in clinical development with cefepime for treatment of infections caused by ESBL- and carbapenemase producing Enterobacteriaceae and P. aeruginosa. It is a new generation broad-spectrum BLI with direct inhibitory activity against serine-active site and emerging metallo-β-lactamases (e.g., VIM/NDM). In previous in vivo and in vitro studies, the PK-PD driver of efficacy of VNRX-5133 was defined as AUC:MIC. Described herein are in vitro studies to assess the magnitude of VNRX-5133 exposure (AUC:MIC) required to restore efficacy of cefepime against a broad collection of KPC- and VIM/NDM-producing Enterobacteriaceae (ENT) and P. aeruginosa (PSA) clinical isolates. Methods Dose-fractionation studies, consisting of four VNRX-5133 exposures fractionated into regimens administered every 4, 8, 12 and 24 hours, were performed in an in vitro infection model with simulated 2 g q8h dosing of cefepime against NDM-1 producing E. coli. A Hill-type model described the relationship between change in log10 CFU at 24 hours and VNRX-5133 exposure (AUC:MIC), where cefepime MIC was determined with 4 µg/mL VNRX-5133. To evaluate variability of efficacy enabled by VNRX-5133 between isolates as well as between Serine-BL and Metallo-BL producers, dose-ranging studies were completed for eight isolates (seven ENT and one PSA) producing KPC or VIM/NDM metallo-β-lactamases. Results The PK-PD exposure parameter AUC:MIC accurately described the efficacy of VNRX-5133 in rescuing cefepime activity against KPC and VIM/NDM carbapenemase-producing isolates of ENT and PSA. The AUC:MIC ratios associated with net bacterial stasis, 1-, and 2-log10 reductions in bacterial burden from baseline were 6.1, 18.4 and 45, respectively, for a collection of five VIM/NDM- and three KPC-producing isolates with cefepime MICs ranging from 4–8 µg/mL with no significant differences observed between Ser-BL and MBL producers. Conclusion These data confirm the equivalent in vitro activity of cefepime/VNRX-5133 against organisms producing serine- and metallo-β-lactamases and provides an initial PK-PD target for VNRX-5133 efficacy when used in combination with cefepime for the treatment of ESBL- and carbapenemase-producing ENT and PSA infections. Disclosures D. Daigle, VenatoRx Pharmaceuticals Inc.: Employee and Shareholder, Salary. S. Vernacchio, VenatoRx Pharmaceuticals Inc.: Employee and Shareholder, Salary. L. Xerri, VenatoRx Pharmaceuticals Inc.: Employee and Shareholder, Salary. D. Pevear, VenatoRx Pharmaceuticals Inc.: Employee, Salary.


Author(s):  
Peng Wang ◽  
Xiao-Xia Hu ◽  
Ying-hui Li ◽  
Nan-Yong Gao ◽  
Guo-quan Chen ◽  
...  

This study was to evaluate the effect of resveratrol on the pharmacokinetics of ticagrelor in rats and the metabolism of ticagrelor in human CYP3A4 and liver microsomes. Eighteen Sprague-Dawley rats were randomly divided into three groups: group A (control group), group B (50mg/kg resveratrol), and group C (150mg/kg resveratrol ). After 30 minutes administration of resveratrol, a single dose of ticagrelor (18mg/kg) was administered orally. The vitro experiment was performed to examine the influence of resveratrol on ticagrelor metabolism in CYP3A4*1, human, and rat liver microsomes. Serial biological samples were assayed by validated UHPLC-MS/MS methods. In vivo study, the AUC and Cmax of ticagrelor in group B and C appeared to be significantly higher than the control group, while Vz/F and CLz/F of ticagrelor in group B and C were significantly decreased. In vitro study, resveratrol exhibited an inhibitory effect on CYP3A4*1, human and rat liver microsomes. The IC50 values of resveratrol were 56.75μM,69.07μM and 14.22μM, respectively. Our results indicated that resveratrol had a inhibitory effect on the metabolism of ticagrelor in vitro and vivo. It should be paid more attention to the clinical combination of resveratrol with ticagrelor and ticagrelor plasma concentration should be monitored to avoid the occurrence of adverse reaction.


Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3382 ◽  
Author(s):  
Chi-Lung Yang ◽  
Ho-Cheng Wu ◽  
Tsong-Long Hwang ◽  
Chu-Hung Lin ◽  
Yin-Hua Cheng ◽  
...  

One new dibenzocycloheptene, validinol (1), and one butanolide firstly isolated from the natural source, validinolide (2), together with 17 known compounds were isolated from the stem of Cinnamomum validinerve. Among the isolates, lincomolide A (3), secosubamolide (7), and cinnamtannin B1 (19) exhibited potent inhibition on both superoxide anion generation (IC50 values of 2.98 ± 0.3 µM, 4.37 ± 0.38 µM, and 2.20 ± 0.3 µM, respectively) and elastase release (IC50 values of 3.96 ± 0.31 µM, 3.04 ± 0.23 µM, and 4.64 ± 0.71 µM, respectively) by human neutrophils. In addition, isophilippinolide A (6), secosubamolide (7), and cinnamtannin B1 (19) showed bacteriostatic effects against Propionibacterium acnes in in vitro study, with minimal inhibitory concentration (MIC) values at 16 μg/mL, 16 μg/mL, and 500 μg/mL, respectively. Further investigations using the in vivo ear P. acnes infection model showed that the intraperitoneal administration of the major component cinnamtannin B1 (19) reduced immune cell infiltration and pro-inflammatory cytokines TNF-α and IL-6 at the infection sites. The results demonstrated the potential of cinnamtannin B1 (19) for acne therapy. In summary, these results demonstrated the anti-inflammatory potentials of Formosan C. validinerve during bacterial infections.


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