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Caselli L, Conti L, De Santis I, Berti D. Small-angle X-ray and neutron scattering applied to lipid-based nanoparticles: Recent advancements across different length scales. Adv Colloid Interface Sci 2024; 327:103156. [PMID: 38643519 DOI: 10.1016/j.cis.2024.103156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 02/28/2024] [Accepted: 04/08/2024] [Indexed: 04/23/2024]
Abstract
Lipid-based nanoparticles (LNPs), ranging from nanovesicles to non-lamellar assemblies, have gained significant attention in recent years, as versatile carriers for delivering drugs, vaccines, and nutrients. Small-angle scattering methods, employing X-rays (SAXS) or neutrons (SANS), represent unique tools to unveil structure, dynamics, and interactions of such particles on different length scales, spanning from the nano to the molecular scale. This review explores the state-of-the-art on scattering methods applied to unveil the structure of lipid-based nanoparticles and their interactions with drugs and bioactive molecules, to inform their rational design and formulation for medical applications. We will focus on complementary information accessible with X-rays or neutrons, ranging from insights on the structure and colloidal processes at a nanoscale level (SAXS) to details on the lipid organization and molecular interactions of LNPs (SANS). In addition, we will review new opportunities offered by Time-resolved (TR)-SAXS and -SANS for the investigation of dynamic processes involving LNPs. These span from real-time monitoring of LNPs structural evolution in response to endogenous or external stimuli (TR-SANS), to the investigation of the kinetics of lipid diffusion and exchange upon interaction with biomolecules (TR-SANS). Finally, we will spotlight novel combinations of SAXS and SANS with complementary on-line techniques, recently enabled at Large Scale Facilities for X-rays and neutrons. This emerging technology enables synchronized multi-method investigation, offering exciting opportunities for the simultaneous characterization of the structure and chemical or mechanical properties of LNPs.
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Affiliation(s)
- Lucrezia Caselli
- Physical Chemistry 1, University of Lund, S-221 00 Lund, Sweden.
| | - Laura Conti
- Consorzio Sistemi a Grande Interfase, Department of Chemistry, University of Florence, Sesto Fiorentino, Italy
| | - Ilaria De Santis
- Department of Chemistry, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, Florence 50019, Italy
| | - Debora Berti
- Department of Chemistry, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, Florence 50019, Italy; Consorzio Sistemi a Grande Interfase, Department of Chemistry, University of Florence, Sesto Fiorentino, Italy.
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2
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Arroyo-Urea EM, Muñoz-Hernando M, Leo-Barriga M, Herranz F, González-Paredes A. A quality by design approach for the synthesis of palmitoyl-L-carnitine-loaded nanoemulsions as drug delivery systems. Drug Deliv 2023; 30:2179128. [PMID: 36803136 PMCID: PMC10184586 DOI: 10.1080/10717544.2023.2179128] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Nanoemulsions (NE) are lipid nanocarriers that can efficiently load hydrophobic active compounds, like palmitoyl-L-carnitine (pC), used here as model molecule. The use of design of experiments (DoE) approach is a useful tool to develop NEs with optimized properties, requiring less experiments compared to trial-and-error approach. In this work, NE were prepared by the solvent injection technique and DoE using a two-level fractional factorial design (FFD) as model was implemented for designing pC-loaded NE. NEs were fully characterized by a combination of techniques, studying its stability, scalability, pC entrapment and loading capacity and biodistribution, which was studied ex-vivo after injection of fluorescent NEs in mice. We selected the optimal composition for NE, named pC-NEU, after analysis of four variables using DoE. pC-NEU incorporated pC in a very efficient manner, with high entrapment efficiency (EE) and loading capacity. pC-NEU did not change its initial colloidal properties stored at 4 °C in water during 120 days, nor in buffers with different pH values (5.3 and 7.4) during 30 days. Moreover, the scalability process did not affect NE properties and stability profile. Finally, biodistribution study showed that pC-NEU formulation was predominantly concentrated in the liver, with minimal accumulation in spleen, stomach, and kidneys.
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Affiliation(s)
- E M Arroyo-Urea
- Nanomedicine and Molecular Imaging group, Instituto de Química Médica-CSIC, Madrid, Spain
| | - María Muñoz-Hernando
- Nanomedicine and Molecular Imaging group, Instituto de Química Médica-CSIC, Madrid, Spain
| | - Marta Leo-Barriga
- Nanomedicine and Molecular Imaging group, Instituto de Química Médica-CSIC, Madrid, Spain
| | - Fernando Herranz
- Nanomedicine and Molecular Imaging group, Instituto de Química Médica-CSIC, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.,Conexión Nanomedicina-CSIC, Madrid, Spain
| | - Ana González-Paredes
- Nanomedicine and Molecular Imaging group, Instituto de Química Médica-CSIC, Madrid, Spain.,Conexión Nanomedicina-CSIC, Madrid, Spain
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3
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Inhibitory Effect against Listeria monocytogenes of Carbon Nanoparticles Loaded with Copper as Precursors of Food Active Packaging. Foods 2022; 11:foods11192941. [PMID: 36230015 PMCID: PMC9562255 DOI: 10.3390/foods11192941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/06/2022] [Accepted: 09/15/2022] [Indexed: 11/17/2022] Open
Abstract
Human listeriosis is a serious foodborne disease of which outbreaks are occurring increasingly frequently in Europe. Around the world, different legal requirements exist to guarantee food safety. Nanomaterials are increasingly used in the food industry as inhibitors of pathogens, and carbon nanomaterials are among the most promising. In the present study, novel carbon nanoparticles loaded with copper (CNP-Cu) were prepared, and their antimicrobial activity against Listeria monocytogenes was assessed. CNPs of two sizes were synthesized and characterized by dynamic light scattering (DLS), electrophoretic light scattering (ELS) and electron microscopy (EM). The minimum inhibitory concentration (MIC) of CNP-Cu was determined in accordance with the available standard. To get insights into its mechanism of action, the release of copper ions into a cell media was assessed by inductively coupled plasma optical emission (ICP-OE), and the ability of loaded CNPs to generate cytotoxic reactive oxygen species (ROS) was evaluated by EPR spectroscopy. Finally, the extent of release of copper in a food simulant was assessed. The results demonstrated the antimicrobial effectiveness of CNP-Cu, with growth inhibition up to 85% and a release of copper that was more pronounced in an acidic food simulant. Overall, the results indicate CNP-Cu as a promising agent for the design of active food packaging which is able to improve food shelf-life.
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Fornasier M, Dessì F, Pireddu R, Sinico C, Carretti E, Murgia S. Lipid vesicular gels for topical administration of antioxidants. Colloids Surf B Biointerfaces 2022; 213:112388. [PMID: 35183999 DOI: 10.1016/j.colsurfb.2022.112388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 01/28/2022] [Accepted: 01/30/2022] [Indexed: 10/19/2022]
Abstract
The application of a formulation on the skin represents an effective way to deliver bio-active molecules for therapeutical purposes. Moreover, the outermost skin layer, the stratum corneum, can be overcome by employing chemical permeation enhancers and edge activators as components. Several lipids can be considered as permeation enhancers, such as the ubiquitous monoolein, one of the most used building blocks for the preparation of lipid liquid crystalline nanoparticles which are applied as drug carriers for nanomedicine applications. Recent papers highlighted how bile salts can affect the phase behavior of monoolein to obtain drug carriers suitable for topical administration, given their role as edge activators into the formulation. Herein, the encapsulation of natural antioxidants (caffeic acid and ferulic acid) into lipid vesicular gels (LVGs) made by monoolein and sodium taurocholate (TC) in water was studied to produce formulations suitable for topical application. TC induces a bicontinuous cubic to multilamellar phase transition for monoolein in water at the given concentrations, and by increasing its content into the formulations, unilamellar LVGs are formed. The encapsulation of the two antioxidants did not affect significantly the structure of the gels. The oscillating rheological studies showed that ferulic acid has a structuring effect on the lipid matrix, in comparison with the empty dispersion and the one containing caffeic acid. These gels were then tested in vitro on new-born pig skin to evaluate their efficacy as drug carriers for topical administration, showing that caffeic acid is mostly retained in the gel whereas ferulic acid is released at a higher degree. The data herein reported provide some further information on the effect of bile salts on the lipid self-assembly to evaluate useful compositions for topical administration of natural antioxidants.
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Affiliation(s)
- Marco Fornasier
- Department of Chemistry, Lund University, SE-22100 Lund, Sweden; CSGI, Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, via della Lastruccia 3, Sesto Fiorentino, Florence I-50019, Italy; Department of Chemical and Geological Sciences, University of Cagliari, s.s 554 bivio Sestu, Monserrato I-09042, Italy.
| | - Francesca Dessì
- CSGI, Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, via della Lastruccia 3, Sesto Fiorentino, Florence I-50019, Italy; Department of Chemical and Geological Sciences, University of Cagliari, s.s 554 bivio Sestu, Monserrato I-09042, Italy
| | - Rosa Pireddu
- Department of Life and Environmental Sciences, University of Cagliari, via Ospedale 72, Cagliari I-09124, Italy
| | - Chiara Sinico
- Department of Life and Environmental Sciences, University of Cagliari, via Ospedale 72, Cagliari I-09124, Italy
| | - Emiliano Carretti
- CSGI, Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, via della Lastruccia 3, Sesto Fiorentino, Florence I-50019, Italy; Chemistry Department "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino I-50019, Italy
| | - Sergio Murgia
- CSGI, Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, via della Lastruccia 3, Sesto Fiorentino, Florence I-50019, Italy; Department of Life and Environmental Sciences, University of Cagliari, via Ospedale 72, Cagliari I-09124, Italy.
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5
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Fornasier M, Porcheddu A, Casu A, Raghavan SR, Jönsson P, Schillén K, Murgia S. Surface-modified nanoerythrosomes for potential optical imaging diagnostics. J Colloid Interface Sci 2020; 582:246-253. [PMID: 32823126 DOI: 10.1016/j.jcis.2020.08.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 08/03/2020] [Accepted: 08/08/2020] [Indexed: 12/29/2022]
Abstract
Nanoerythrosomes (NERs), vesicle-like nanoparticles derived from red blood cells, represent a new and interesting vector for therapeutic molecules and imaging probes, mainly thanks to their high stability and excellent biocompatibility. Aiming to present a proof-of-concept of the use of NERs as diagnostic tools for in vitro/in vivo imaging purposes, we report here several functionalization routes to decorate the surfaces of NERs derived from bovine blood with two different fluorophores: 7-amino-4-methylcumarin and dibenzocyclooctinecyanine5.5. Notably, the fluorophores were cross-linked to the NERs surface with glutaraldehyde and, in the case of dibenzocyclooctinecyanine5.5, also using a click-chemistry route, termed strain-promoted azide-alkyne cycloaddition. The physicochemical characterization highlighted the high stability of the NERs derivatives in physiological conditions. Furthermore, the loading efficiency of the fluorophores on the NERs surface was evaluated using both UV-Vis spectroscopy and fluorescence microscopy.
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Affiliation(s)
- Marco Fornasier
- Department of Chemical and Geological Sciences, University of Cagliari, s.s. 554 bivio Sestu, I-09042 Monserrato, Cagliari, Italy; CSGI, Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence, Italy.
| | - Andrea Porcheddu
- Department of Chemical and Geological Sciences, University of Cagliari, s.s. 554 bivio Sestu, I-09042 Monserrato, Cagliari, Italy
| | - Anna Casu
- Translational Research Institute-AdventHealth, Orlando, FL, USA
| | - Srinivasa R Raghavan
- Department of Chemical & Biomolecular Engineering, University of Maryland, College Park, ML 20742, USA
| | - Peter Jönsson
- Division of Physical Chemistry, Department of Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
| | - Karin Schillén
- Division of Physical Chemistry, Department of Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
| | - Sergio Murgia
- Department of Chemical and Geological Sciences, University of Cagliari, s.s. 554 bivio Sestu, I-09042 Monserrato, Cagliari, Italy; CSGI, Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence, Italy.
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6
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Eleraky NE, Allam A, Hassan SB, Omar MM. Nanomedicine Fight against Antibacterial Resistance: An Overview of the Recent Pharmaceutical Innovations. Pharmaceutics 2020; 12:E142. [PMID: 32046289 PMCID: PMC7076477 DOI: 10.3390/pharmaceutics12020142] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/29/2020] [Accepted: 02/04/2020] [Indexed: 12/16/2022] Open
Abstract
Based on the recent reports of World Health Organization, increased antibiotic resistance prevalence among bacteria represents the greatest challenge to human health. In addition, the poor solubility, stability, and side effects that lead to inefficiency of the current antibacterial therapy prompted the researchers to explore new innovative strategies to overcome such resilient microbes. Hence, novel antibiotic delivery systems are in high demand. Nanotechnology has attracted considerable interest due to their favored physicochemical properties, drug targeting efficiency, enhanced uptake, and biodistribution. The present review focuses on the recent applications of organic (liposomes, lipid-based nanoparticles, polymeric micelles, and polymeric nanoparticles), and inorganic (silver, silica, magnetic, zinc oxide (ZnO), cobalt, selenium, and cadmium) nanosystems in the domain of antibacterial delivery. We provide a concise description of the characteristics of each system that render it suitable as an antibacterial delivery agent. We also highlight the recent promising innovations used to overcome antibacterial resistance, including the use of lipid polymer nanoparticles, nonlamellar liquid crystalline nanoparticles, anti-microbial oligonucleotides, smart responsive materials, cationic peptides, and natural compounds. We further discuss the applications of antimicrobial photodynamic therapy, combination drug therapy, nano antibiotic strategy, and phage therapy, and their impact on evading antibacterial resistance. Finally, we report on the formulations that made their way towards clinical application.
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Affiliation(s)
- Nermin E. Eleraky
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt; (N.E.E.); (A.A.)
| | - Ayat Allam
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt; (N.E.E.); (A.A.)
- Assiut International Center of Nanomedicine, Al-Rajhy Liver Hospital, Assiut University, Assiut 71515, Egypt
| | - Sahar B. Hassan
- Department of Clinical pharmacy, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt;
| | - Mahmoud M. Omar
- Department of Pharmaceutics and Industrial Pharmacy, Deraya University, Minia 61768, Egypt
- Department of Pharmaceutics and Clinical Pharmacy, Faculty of Pharmacy Sohag University, Sohag 82524, Egypt
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7
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González-Paredes A, Sitia L, Ruyra A, Morris CJ, Wheeler GN, McArthur M, Gasco P. Solid lipid nanoparticles for the delivery of anti-microbial oligonucleotides. Eur J Pharm Biopharm 2018; 134:166-177. [PMID: 30468838 DOI: 10.1016/j.ejpb.2018.11.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 11/18/2018] [Accepted: 11/19/2018] [Indexed: 12/29/2022]
Abstract
Novel alternatives to antibiotics are urgently needed for the successful treatment of antimicrobial resistant (AMR) infections. Experimental antibacterial oligonucleotide therapeutics, such as transcription factor decoys (TFD), are a promising approach to circumvent AMR. However, the therapeutic potential of TFD is contingent upon the development of carriers that afford efficient DNA protection against nucleases and delivery of DNA to the target infection site. As a carrier for TFD, here we present three prototypes of anionic solid lipid nanoparticles that were coated with either the cationic bolaamphiphile 12-bis-tetrahydroacridinium or with protamine. Both compounds switched particles zeta potential to positive values, showing efficient complexation with TFD and demonstrable protection from deoxyribonuclease. The effective delivery of TFD into bacteria was confirmed by confocal microscopy while SLN-bacteria interactions were studied by flow cytometry. Antibacterial efficacy was confirmed using a model TFD targeting the Fur iron uptake pathway in E. coli under microaerobic conditions. Biocompatibility of TFD-SLN was assessed using in vitro epithelial cell and in vivo Xenopus laevis embryo models. Taken together these results indicate that TFD-SLN complex can offer preferential accumulation of TFD in bacteria and represent a promising class of carriers for this experimental approach to tackling the worldwide AMR crisis.
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Affiliation(s)
| | - Leopoldo Sitia
- Procarta Biosystems Ltd., Innovation Centre, Norwich Research Park, Norwich NR4 7UH, UK; Norwich Medical School, University of East Anglia, Norwich NR4 7UQ, UK
| | - Angels Ruyra
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | | | - Grant N Wheeler
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - Michael McArthur
- Procarta Biosystems Ltd., Innovation Centre, Norwich Research Park, Norwich NR4 7UH, UK; Norwich Medical School, University of East Anglia, Norwich NR4 7UQ, UK
| | - Paolo Gasco
- Nanovector Srl., Via Livorno 60, 10144 Turin, Italy
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8
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Mamusa M, Salvatore A, Berti D. Structural Modifications of DPPC Bilayers upon Inclusion of an Antibacterial Cationic Bolaamphiphile. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:8952-8961. [PMID: 29976066 DOI: 10.1021/acs.langmuir.8b01689] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The emergence of antibiotic-resistant bacterial strains has fostered fundamental research to develop alternative antimicrobial strategies. Among the several systems proposed so far, the association complexes (nanoplexes) formed by transcription factor decoys (TFDs), i.e., short oligonucleotides targeting a crucial bacterial transcription factor, and a bolaform cationic amphiphile, 10,10'-(dodecane-1,12-diyl)-bis-(9-amino-1,2,3,4-tetrahydroacridinium) chloride (12-bis-THA), have demonstrated their potential in vitro and in vivo. The application of these nanoplexes is hampered by a scarce colloidal stability, which can be addressed by including the bolaamphiphile in a liposomal carrier, which is then associated to the TFD. The present study reports an investigation on the effects of 12-bis-THA on the structure of synthetic lipid bilayers to assess the morphology of the mixed assemblies, gain insight into the location of the host within the bilayer, and determine the loading capacity of the carrier. Our results demonstrate that 12-bis-THA promptly inserts within 1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DPPC) bilayers, bending its C-12 spacer chain to adopt a conelike shape and shifting the gel-liquid crystalline transition of the chains to lower temperatures. The host liposomal structure is retained for a bolaamphiphile concentration of up to 3.2% mol to DPPC, whereas higher concentrations lead to the destabilization by means of a detergency-like mechanism, with the simultaneous existence of different lamellar-based structures, such as liposomes, bicelles, and rafts, in which DPPC and 12-bis-THA could be present in different molar ratios. Overall, these results shed light on the interaction of the bolaamphiphile with a lipid bilayer and provide valuable insight to better formulate the antimicrobial amphiphile in liposomal carriers to circumvent the colloidal instability of nanoplexes.
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Affiliation(s)
- M Mamusa
- CSGI and Department of Chemistry "Ugo Schiff" , University of Florence , Sesto Fiorentino (FI) 50019 , Italy
| | - A Salvatore
- CSGI and Department of Chemistry "Ugo Schiff" , University of Florence , Sesto Fiorentino (FI) 50019 , Italy
| | - D Berti
- CSGI and Department of Chemistry "Ugo Schiff" , University of Florence , Sesto Fiorentino (FI) 50019 , Italy
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9
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Hegarty JP, Stewart DB. Advances in therapeutic bacterial antisense biotechnology. Appl Microbiol Biotechnol 2017; 102:1055-1065. [PMID: 29209794 DOI: 10.1007/s00253-017-8671-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 11/16/2017] [Accepted: 11/17/2017] [Indexed: 12/15/2022]
Abstract
Antisense therapeutics are a biotechnological form of antibiotic therapy using chemical analogues of short single-stranded nucleic acid sequences modified to form stable oligomers. These molecules are termed antisense oligonucleotides (ASOs) because their sequence is complementary, via Watson-Crick specific base pairing, to their target messenger RNA (mRNA). ASOs modify gene expression in this sequence-dependent manner by binding to its complementary mRNA and inhibiting its translation into protein through steric blockage and/or through RNase degradation of the ASO/RNA duplex. The widespread use of conventional antibiotics has led to the increasing emergence of multiple drug-resistant pathogenic bacteria. There is an urgent need to develop alternative therapeutic strategies to reduce the morbidity and mortality associated with bacterial infections, and until recently, the use of ASOs as therapeutic agents has been essentially limited to eukaryotic cells, with ASOs as antibacterials having been largely unexplored primarily due to the poor uptake efficiency of antisense molecules by bacteria. There are conceptual advantages to bacterial antisense antibiotic therapies, including a sequence-dependent approach that allows for a rational design to multiple specific molecular targets. This review summarizes the current knowledge of antisense bacterial biotechnology and highlights the recent progress and the current obstacles in their development for therapeutic applications.
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Affiliation(s)
- John P Hegarty
- College of Medicine, Department of Surgery, The Pennsylvania State University, 500 University Drive, H137, P.O. Box 850, Hershey, PA, 17033-0850, USA
| | - David B Stewart
- College of Medicine, Department of Surgery, The Pennsylvania State University, 500 University Drive, H137, P.O. Box 850, Hershey, PA, 17033-0850, USA.
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