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Hijazi DM, Dahabiyeh LA, Abdelrazig S, Alqudah DA, Al-Bakri AG. Micafungin effect on Pseudomonas aeruginosa metabolome, virulence and biofilm: potential quorum sensing inhibitor. AMB Express 2023; 13:20. [PMID: 36807839 PMCID: PMC9941417 DOI: 10.1186/s13568-023-01523-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 01/30/2023] [Indexed: 02/22/2023] Open
Abstract
The prevalence of antibiotic resistance in Pseudomonas aeruginosa places a heavy burden on the health care sectors urging the need to find alternative, non-antibiotic strategies. The interference with the P. aeruginosa quorum sensing (QS) system represents a promising alternative strategy to attenuate the bacterial virulency and its ability to form biofilms. Micafungin has been reported to impede the pseudomonal biofilm formation. However, the influences of micafungin on the biochemical composition and metabolites levels of P. aeruginosa have not been explored. In this study, the effect of micafungin (100 µg/mL) on the virulence factors, QS signal molecules and the metabolome of P. aeruginosa was studied using exofactor assay and mass spectrometry-based metabolomics approaches. Furthermore, confocal laser scanning microscopy (CLSM) using the fluorescent dyes ConA-FITC and SYPRO® Ruby was used to visualize micafungin disturbing effects on the pseudomonal glycocalyx and protein biofilm-constituents, respectively. Our findings showed that micafungin significantly decreased the production of various QS-controlled virulence factors (pyocyanin, pyoverdine, pyochelin and rhamnolipid), along with a dysregulation in the level of various metabolites involved in QS system, lysine degradation, tryptophan biosynthesis, TCA cycle, and biotin metabolism. In addition, the CLSM examination showed an altered matrix distribution. The presented findings highlight the promising role of micafungin as a potential quorum sensing inhibitor (QSI) and anti-biofilm agent to attenuate P. aeruginosa pathogenicity. In addition, they point to the promising role of metabolomics study in investigating the altered biochemical pathways in P. aeruginosa.
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Affiliation(s)
- Duaa M. Hijazi
- grid.9670.80000 0001 2174 4509Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, 11942 Jordan
| | - Lina A. Dahabiyeh
- grid.9670.80000 0001 2174 4509Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, 11942 Jordan
| | - Salah Abdelrazig
- grid.9763.b0000 0001 0674 6207Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Khartoum, 1996, 11115 Khartoum, Sudan ,grid.4563.40000 0004 1936 8868Centre for Analytical Bioscience, Advanced Materials and Healthcare Technologies Division, School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD UK
| | - Dana A. Alqudah
- grid.9670.80000 0001 2174 4509Cell Therapy Center, The University of Jordan, Amman, 11942 Jordan
| | - Amal G. Al-Bakri
- grid.9670.80000 0001 2174 4509Department of Pharmaceutics and Pharmaceutical Technology, School of Pharmacy, The University of Jordan, Amman, 11942 Jordan
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Alves-Barroco C, Botelho AMN, Américo MA, Fracalanzza SEL, de Matos APA, Guimaraes MA, Ferreira-Carvalho BT, Figueiredo AMS, Fernandes AR. Assessing in vivo and in vitro biofilm development by Streptococcus dysgalactiae subsp. dysgalactiae using a murine model of catheter-associated biofilm and human keratinocyte cell. Front Cell Infect Microbiol 2022; 12:874694. [PMID: 35928206 PMCID: PMC9343579 DOI: 10.3389/fcimb.2022.874694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 06/29/2022] [Indexed: 11/13/2022] Open
Abstract
Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) is an important agent of bovine mastitis. This infection causes an inflammatory reaction in udder tissue, being the most important disease-causing significant impact on the dairy industry. Therefore, it leads to an increase in dairy farming to meet commercial demands. As a result, there is a major impact on both the dairy industry and the environment including global warming. Recurrent mastitis is often attributed to the development of bacterial biofilms, which promote survival of sessile cells in hostile environments, and resistance to the immune system defense and antimicrobial therapy. Recently, we described the in vitro biofilm development on abiotic surfaces by bovine SDSD. In that work we integrated microbiology, imaging, and computational methods to evaluate the biofilm production capability of SDSD isolates on abiotic surfaces. Additionally, we reported that bovine SDSD can adhere and internalize human cells, including human epidermal keratinocyte (HEK) cells. We showed that the adherence and internalization rates of bovine SDSD isolates in HEK cells are higher than those of a SDSD DB49998-05 isolated from humans. In vivo, bovine SDSD can cause invasive infections leading to zebrafish morbidity and mortality. In the present work, we investigated for the first time the capability of bovine SDSD to develop biofilm in vivo using a murine animal model and ex-vivo on human HEK cells. Bovine SDSD isolates were selected based on their ability to form weak, moderate, or strong biofilms on glass surfaces. Our results showed that SDSD isolates displayed an increased ability to form biofilms on the surface of catheters implanted in mice when compared to in vitro biofilm formation on abiotic surface. A greater ability to form biofilm in vitro after animal passage was observed for the VSD45 isolate, but not for the other isolates tested. Besides that, in vitro scanning electron microscopy demonstrated that SDSD biofilm development was visible after 4 hours of SDSD adhesion to HEK cells. Cell viability tests showed an important reduction in the number of HEK cells after the formation of SDSD biofilms. In this study, the expression of genes encoding BrpA-like (biofilm regulatory protein), FbpA (fibronectin-binding protein A), HtrA (serine protease), and SagA (streptolysin S precursor) was higher for biofilm grown in vivo than in vitro, suggesting a potential role for these virulence determinants in the biofilm-development, host colonization, and SDSD infections. Taken together, these results demonstrate that SDSD can develop biofilms in vivo and on the surface of HEK cells causing important cellular damages. As SDSD infections are considered zoonotic diseases, our data contribute to a better understanding of the role of biofilm accumulation during SDSD colonization and pathogenesis not only in bovine mastitis, but they also shed some lights on the mechanisms of prosthesis-associated infection and cellulitis caused by SDSD in humans, as well.
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Affiliation(s)
- Cinthia Alves-Barroco
- UCIBIO - Applied Molecular Biosciences Unit, Dept. Ciências da Vida, NOVA School of Science and Technology, Caparica, Portugal
- i4HB, Associate Laboratory - Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Ana Maria Nunes Botelho
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marco Antonio Américo
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - António P. Alves de Matos
- Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Egas Moniz - Cooperativa de Ensino Superior CRL, Quinta da Granja, Portugal
| | - Márcia Aparecida Guimaraes
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Agnes Marie Sá Figueiredo
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- *Correspondence: Alexandra R. Fernandes, ; Agnes Marie Sá Figueiredo,
| | - Alexandra R. Fernandes
- UCIBIO - Applied Molecular Biosciences Unit, Dept. Ciências da Vida, NOVA School of Science and Technology, Caparica, Portugal
- i4HB, Associate Laboratory - Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
- *Correspondence: Alexandra R. Fernandes, ; Agnes Marie Sá Figueiredo,
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Pharmacodynamics of Moxifloxacin, Meropenem, Caspofungin and their Combinations Against In Vitro Polymicrobial Inter-kingdom Biofilms. Antimicrob Agents Chemother 2021; 66:e0214921. [PMID: 34930026 DOI: 10.1128/aac.02149-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Biofilms colonize medical devices and are often recalcitrant to antibiotics. Inter-kingdom biofilms, when at least a bacterium and a fungus are co-isolated, increase the likelihood of therapeutic failures. In this work, a three-species in vitro biofilm model including S. aureus, E. coli and C. albicans was used to study the activity of the antibiotics moxifloxacin and meropenem, the antifungal caspofungin, and combinations of them against inter-kingdom biofilms. The culturable cells and total biomass were evaluated to determine the pharmacodynamic parameters of the drug response for the incubation with the drugs alone. The synergic or antagonistic effects (increased/decreased effects) of the combination of drugs were analysed with the highest single agent method. Biofilms were imaged in confocal microscopy after live/dead staining. The drugs had limited activity when used alone against single-, dual- or three-species biofilms. When used in combination, additive effects were observed against single- or dual-species biofilms, and increased effects (synergy) against biomass of three-species biofilms. In addition, the two antibiotics showed different patterns, moxifloxacin being more active when targeting S. aureus and meropenem when targeting E. coli. All these observations were confirmed by confocal microscopy images. Our findings highlight the interest in combining caspofungin with antibiotics against inter-kingdom biofilms.
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Scheunemann G, Fortes BN, Lincopan N, Ishida K. Caspofungin Inhibits Mixed Biofilms of Candida albicans and Methicillin-Resistant Staphylococcus aureus and Displays Effectiveness in Coinfected Galleria mellonella Larvae. Microbiol Spectr 2021; 9:e0074421. [PMID: 34643410 PMCID: PMC8515925 DOI: 10.1128/spectrum.00744-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 09/01/2021] [Indexed: 01/05/2023] Open
Abstract
Candida albicans and Staphylococcus aureus are pathogens commonly isolated from bloodstream infections worldwide. While coinfection by both pathogens is associated with mixed biofilms and more severe clinical manifestations, due to the combined expression of virulence and resistance factors, effective treatments remain a challenge. In this study, we evaluated the activity of echinocandins, especially caspofungin, against mixed biofilms of C. albicans and methicillin-resistant (MRSA) or methicillin-susceptible S. aureus (MSSA) and their effectiveness in vivo using the Galleria mellonella coinfection model. Although caspofungin (CAS) and micafungin (MFG) inhibited the mixed biofilm formation, with CAS exhibiting inhibitory activity at lower concentrations, only CAS was active against preformed mixed biofilms. CAS significantly decreased the total biomass of mixed biofilms at concentrations of ≥2 μg/ml, whereas the microbial viability was reduced at high concentrations (32 to 128 μg/ml), leading to fungus and bacterium cell wall disruption and fungal cell enlargement. Notably, CAS (20 or 50 mg/kg of body weight) treatment led to an increased survival and improved outcomes of G. mellonella larvae coinfected with C. albicans and MRSA, since a significant reduction of fungal and bacterial burden in larval tissues was achieved with induction of granuloma formation. Our results reveal that CAS can be a therapeutic option for the treatment of mixed infections caused by C. albicans and S. aureus, supporting additional investigation. IMPORTANCE Infections by microorganisms resistant to antimicrobials is a major challenge that leads to high morbidity and mortality rates and increased time and cost with hospitalization. It was estimated that 27 to 56% of bloodstream infections by C. albicans are polymicrobial, with S. aureus being one of the microorganisms commonly coisolated worldwide. About 80% of infections are associated with biofilms by single or mixed species that can be formed on invasive medical devices, e.g., catheter, and are considered a dissemination source. The increased resistance to antimicrobials in bacterial and fungal cells when they are in biofilms is the most medically relevant behavior that frequently results in therapeutic failure. Although there are several studies evaluating treatments for polymicrobial infections associated or not with biofilms, there is still no consensus on an effective antimicrobial therapy to combat the coinfection by bacteria and fungi.
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Affiliation(s)
- Gaby Scheunemann
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Bruna N. Fortes
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Nilton Lincopan
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Kelly Ishida
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Titanium implant coating based on dopamine-functionalized sulphated hyaluronic acid: in vivo assessment of biocompatibility and antibacterial efficacy. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2021; 128:112286. [PMID: 34474837 DOI: 10.1016/j.msec.2021.112286] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 06/11/2021] [Accepted: 06/25/2021] [Indexed: 11/20/2022]
Abstract
The number of total knee and/or hip replacements are expected to exceed 5 million a year by 2030; the incidence of biofilm-associated complications can vary from 1% in primary implants to 5.6% in case of revision. The purpose of this study was to test the ability of sHA-DA, a partially sulphated hyaluronic acid (sHA) functionalized with a dopamine (DA) moiety, to prevent acute bacterial growth in an in vivo model of an intra-operatively highly contaminated implant. Previously, in vitro studies showed that the DA moiety guarantees good performance as binding agent for titanium surface adhesion, while the negatively charged sHA has both a high efficiency in electrostatic binding of positively charged antibiotics, and bone regenerative effects. The in vitro testing also highlighted the effectiveness of the sHA-DA system in inhibiting bacterial spreading through a sustained release of the antibiotic payload from the implant coating. In this study the chemical stability of the sHA-DA to β-ray sterilization was demonstrated, based on evaluation by NMR, SEC-TDA Omnisec and HPLC-MS analysis, thus supporting the approach of terminal sterilization of the coated implant with no loss of efficacy. Furthermore, an in vivo study in rabbits was performed according to UNI EN ISO 10993-6 to assess the histocompatibility of titanium nails pre-coated with sHA-DA. The implants, placed in the femoral medullary cavity and harvested after 12 weeks, proved to be histocompatible and to allow bone growth in adhesion to the metal surface. Finally, an in vivo model of bacterial contamination was set up by injecting 1 mL of bacterial suspension containing 104 or 106 CFU of methicillin-resistant Staphylococcus aureus (MRSA) into the femoral medullary cavity of 30 rabbits. Titanium nails either uncoated or pre-coated with sHA-DA and loaded directly by the surgeon with 5% vancomycin were implanted in the surgical site. After 1 week, only the animals treated with pre-coated nails did not show the presence of systemic or local bacterial infection, as confirmed by microbiology and histology (Smeltzer score). Further insights into the animal model setup are crucial, however the results obtained suggest that the system can be effective in preventing the onset of the bacterial infective process.
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Nagaraj S, Manivannan S, Narayan S. Potent antifungal agents and use of nanocarriers to improve delivery to the infected site: A systematic review. J Basic Microbiol 2021; 61:849-873. [PMID: 34351655 DOI: 10.1002/jobm.202100204] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 07/29/2021] [Accepted: 08/01/2021] [Indexed: 01/30/2023]
Abstract
There are four major classes of antifungals with the predominant mechanism of action being targeting of cell wall or cell membrane. As in other drugs, low solubility of these compounds has led to low bioavailability in target tissues. Enhanced drug dosages have effects such as toxicity, drug-drug interactions, and increased drug resistance by fungi. This article reviews the current state-of-the-art of antifungals, structure, mechanism of action, other usages, and toxic side effects. The emergence of nanoformulations to transport and uniformly release cargo at the target site is a boon in antifungal treatment. The article details research that lead to the development of nanoformulations of antifungals and potential advantages and avoidance of the lacunae characterizing conventional drugs. A range of nanoformulations based on liposomes, polymers are in various stages of research and their potential advantages have been brought out. It could be observed that under similar dosages, test models, and duration, nanoformulations provided enhanced activity, reduced toxicity, higher uptake and higher immunostimulatory effects. In most instances, the mechanism of antifungal activity of nanoformulations was similar to that of regular antifungal. There are possibilities of coupling multiple antifungals on the same nano-platform. Increased activity coupled with multiple mechanisms of action presents for nanoformulations a tremendous opportunity to overcome antifungal resistance. In the years to come, robust methods for the preparation of nanoformulations taking into account the repeatability and reproducibility in action, furthering the studies on nanoformulation toxicity and studies of human models are required before extensive use of nanoformulations as a prescribed drug.
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Affiliation(s)
- Saraswathi Nagaraj
- Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Chennai, Tamilnadu, India
| | - Sivakami Manivannan
- Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Chennai, Tamilnadu, India
| | - Shoba Narayan
- Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Chennai, Tamilnadu, India
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Fernandes L, Fortes BN, Lincopan N, Ishida K. Caspofungin and Polymyxin B Reduce the Cell Viability and Total Biomass of Mixed Biofilms of Carbapenem-Resistant Pseudomonas aeruginosa and Candida spp. Front Microbiol 2020; 11:573263. [PMID: 33391197 PMCID: PMC7772422 DOI: 10.3389/fmicb.2020.573263] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 11/20/2020] [Indexed: 12/18/2022] Open
Abstract
Pseudomonas aeruginosa and Candida spp. are biofilm-forming pathogens commonly found colonizing medical devices, being mainly associated with pneumonia and bloodstream infections. The coinfection by these pathogens presents higher mortality rates when compared to those caused by a single microbial species. This study aimed to evaluate the antibiofilm activity of echinocandins and polymyxin B (PMB) against polymicrobial biofilms of carbapenem-resistant (CR) Pseudomonas aeruginosa and Candida spp. (C. albicans, C. parapsilosis, C. tropicalis, and C. glabrata). In addition, we tested the antimicrobial effect on their planktonic and monomicrobial biofilm counterparties. Interestingly, beyond inhibition of planktonic [minimum inhibitory concentration (MIC) = 0.5 μg/ml] and biofilm [minimum biofilm inhibitory concentration (MBIC)50 ≤ 2–8 μg/ml] growth of P. aeruginosa, PMB was also effective against planktonic cells of C. tropicalis (MIC = 2 μg/ml), and polymicrobial biofilms of CR P. aeruginosa with C. tropicalis (MBIC50 ≤ 2 μg/ml), C. parapsilosis (MBIC50 = 4–16 μg/ml), C. glabrata (MBIC50 = 8–16 μg/ml), or C. albicans (MBIC50 = 8–64 μg/ml). On the other hand, while micafungin (MFG) showed highest inhibitory activity against planktonic (MIC ≤ 0.008–0.5 μg/ml) and biofilm (MBIC50 ≤ 2–16 μg/ml) growth of Candida spp.; caspofungin (CAS) displays inhibitory activity against planktonic cells (MIC = 0.03–0.25 μg/ml) and monomicrobial biofilms (MBIC50 ≤ 2–64 μg/ml) of Candida spp., and notably on planktonic and monomicrobial biofilms of CR P. aeruginosa (MIC or MBIC50 ≥ 64 μg/ml). Particularly, for mixed biofilms, while CAS reduced significantly viable cell counts of CR P. aeruginosa and Candida spp. at ≥32 and ≥ 2 μg/ml, respectively; PMB was effective in reducing viable cells of CR P. aeruginosa at ≥2 μg/ml and Candida spp. at ≥8 μg/ml. Similar reduction of viable cells was observed for CAS (32–64 μg/ml) combined with PMB (2 μg/ml). These findings highlight the potential of PMB and CAS for the treatment of polymicrobial infections caused by Candida spp. and critical priority CR P. aeruginosa.
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Affiliation(s)
- Luciana Fernandes
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Bruna Nakanishi Fortes
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Nilton Lincopan
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Kelly Ishida
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Abstract
Despite efforts to develop new antibiotics, antibacterial resistance still develops too fast for drug discovery to keep pace. Often, resistance against a new drug develops even before it reaches the market. This continued resistance crisis has demonstrated that resistance to antibiotics with single protein targets develops too rapidly to be sustainable. Most successful long-established antibiotics target more than one molecule or possess targets, which are encoded by multiple genes. This realization has motivated a change in antibiotic development toward drug candidates with multiple targets. Some mechanisms of action presuppose multiple targets or at least multiple effects, such as targeting the cytoplasmic membrane or the carrier molecule bactoprenol phosphate and are therefore particularly promising. Moreover, combination therapy approaches are being developed to break antibiotic resistance or to sensitize bacteria to antibiotic action. In this Review, we provide an overview of antibacterial multitarget approaches and the mechanisms behind them.
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Affiliation(s)
- Declan Alan Gray
- Newcastle University
Biosciences Institute, Newcastle University, NE2 4HH Newcastle
upon Tyne, United Kingdom
| | - Michaela Wenzel
- Division of Chemical
Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
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Guarise C, Barbera C, Pavan M, Pluda S, Celestre M, Galesso D. Dopamine-functionalized sulphated hyaluronic acid as a titanium implant coating enhances biofilm prevention and promotes osseointegration. BIOFOULING 2018; 34:719-730. [PMID: 30270674 DOI: 10.1080/08927014.2018.1491555] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 06/14/2018] [Accepted: 06/14/2018] [Indexed: 06/08/2023]
Abstract
A series of new hyaluronan derivatives was synthesized and tested as an antibiotic release system by antibacterial and osseointegration assays. Specifically, partially sulphated hyaluronic acid (sHA) was functionalized with dopamine (DA). The DA moiety guarantees good performance as a binding agent for coating a titanium alloy surface; furthermore, the negatively charged sHA has bone regenerative effects and a high binding affinity for positively charged antibiotics. A sHA scaffold with a defined degree of sulphation (DS =2) was selected as a good compromise between a high negative charge density and poor heparin-like anticoagulant activity, while the degree of DA derivatization (17.1%mol) was chosen based on the absence of cytotoxic activity and the promotion of osteoblast proliferation. The titanium alloy coating was investigated indirectly using a fluorescent probe and directly by environmental scanning electron microscope (ESEM) analysis. Long-duration antibiotic release was demonstrated in vitro, and antibacterial efficacy against a Staphylococcus aureus culture was shown.
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Affiliation(s)
| | - Carlo Barbera
- a R&D, Fidia Farmaceutici S.p.A. , Abano Terme , Italy
| | - Mauro Pavan
- a R&D, Fidia Farmaceutici S.p.A. , Abano Terme , Italy
| | - Stefano Pluda
- a R&D, Fidia Farmaceutici S.p.A. , Abano Terme , Italy
| | - Micol Celestre
- b Department of Pharmaceutical and Pharmacological Sciences , University of Padova , Padova , Italy
| | - Devis Galesso
- a R&D, Fidia Farmaceutici S.p.A. , Abano Terme , Italy
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