1
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2017-2018. MASS SPECTROMETRY REVIEWS 2023; 42:227-431. [PMID: 34719822 DOI: 10.1002/mas.21721] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 07/26/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
This review is the tenth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization mass spectrometry (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2018. Also included are papers that describe methods appropriate to glycan and glycoprotein analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, new methods, matrices, derivatization, MALDI imaging, fragmentation and the use of arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Most of the applications are presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and highlights the impact that MALDI imaging is having across a range of diciplines. MALDI is still an ideal technique for carbohydrate analysis and advancements in the technique and the range of applications continue steady progress.
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Affiliation(s)
- David J Harvey
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, UK
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2
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Heine H, Zamyatina A. Therapeutic Targeting of TLR4 for Inflammation, Infection, and Cancer: A Perspective for Disaccharide Lipid A Mimetics. Pharmaceuticals (Basel) 2022; 16:23. [PMID: 36678520 PMCID: PMC9864529 DOI: 10.3390/ph16010023] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/28/2022] Open
Abstract
The Toll-like receptor 4 (TLR4) signaling pathway plays a central role in the prompt defense against infectious challenge and provides immediate response to Gram-negative bacterial infection. The TLR4/MD-2 complex can sense and respond to various pathogen-associated molecular patterns (PAMPs) with bacterial lipopolysaccharide (LPS) being the most potent and the most frequently occurring activator of the TLR4-mediated inflammation. TLR4 is believed to be both a friend and foe since improperly regulated TLR4 signaling can result in the overactivation of immune responses leading to sepsis, acute lung injury, or pathologic chronic inflammation involved in cancer and autoimmune disease. TLR4 is also considered a legitimate target for vaccine adjuvant development since its activation can boost the adaptive immune responses. The dual action of the TLR4 complex justifies the efforts in the development of both TLR4 antagonists as antisepsis drug candidates or remedies for chronic inflammatory diseases and TLR4 agonists as vaccine adjuvants or immunotherapeutics. In this review, we provide a brief overview of the biochemical evidences for possible pharmacologic applications of TLR4 ligands as therapeutics and report our systematic studies on the design, synthesis, and immunobiological evaluation of carbohydrate-based TLR4 antagonists with nanomolar affinity for MD-2 as well as disaccharide-based TLR4 agonists with picomolar affinity for the TLR4/MD-2 complex.
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Affiliation(s)
- Holger Heine
- Research Group Innate Immunity, Research Center Borstel—Leibniz Lung Center, Airway Research Center North (ARCN), German Center for Lung Research (DZL), Parkallee 22, 23845 Borstel, Germany
| | - Alla Zamyatina
- Department of Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
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3
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Verboni M, Benedetti S, Campana R, Palma F, Potenza L, Sisti M, Duranti A, Lucarini S. Synthesis and Biological Characterization of the New Glycolipid Lactose Undecylenate (URB1418). Pharmaceuticals (Basel) 2022; 15:ph15040456. [PMID: 35455453 PMCID: PMC9030338 DOI: 10.3390/ph15040456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/01/2022] [Accepted: 04/03/2022] [Indexed: 11/16/2022] Open
Abstract
As a follow-up to our previous studies on glycolipid surfactants, a new molecule, that is lactose 6′-O-undecylenate (URB1418), was investigated. To this end, a practical synthesis and studies aimed at exploring its specific properties were carried out. URB1418 showed antifungal activities against Trichophyton rubrum F2 and Candida albicans ATCC 10231 (MIC 512 μg/mL) and no significant antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. At the same time, it presented anti-inflammatory properties, as documented by the dose-dependent reduction in LPS-induced NO release in RAW 264.7 cells, while a low antioxidant capacity in the range of concentrations tested (EC50 > 200 µM) was also observed. Moreover, URB1418 offers the advantage of being more stable than the reference polyunsaturated lactose esters and of being synthesized using a “green” procedure, involving an enzymatic method, high yield and low manufacturing cost. For all these reasons and the absence of toxicity (HaCaT cells), the new glycolipid presented herein could be considered an interesting compound for applications in various fields.
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Garcia-Vello P, Di Lorenzo F, Zucchetta D, Zamyatina A, De Castro C, Molinaro A. Lipopolysaccharide lipid A: A promising molecule for new immunity-based therapies and antibiotics. Pharmacol Ther 2022; 230:107970. [PMID: 34454000 DOI: 10.1016/j.pharmthera.2021.107970] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/24/2021] [Accepted: 07/22/2021] [Indexed: 12/15/2022]
Abstract
Lipopolysaccharides (LPS) are the main components of the external leaflet of the Gram-negative outer membrane and consist of three different moieties: lipid A, core oligosaccharide, and O-polysaccharide. The lipid A is a glucosamine disaccharide with different levels of acylation and phosphorylation, beside carrying, in certain cases, additional substituents on the sugar backbone. It is also the main immunostimulatory part of the LPS, as its recognition by the host immune system represents a fundamental event for detection of perilous microorganisms. Moreover, an uncontrolled immune response caused by a large amount of circulating LPS can lead to dramatic outcomes for human health, such as septic shock. The immunostimulant properties of an LPS incredibly vary depending on lipid A chemical structure, and for this reason, natural and synthetic variants of the lipid A are under study to develop new drugs that mimic or antagonise its natural effects. Here, we review past and recent findings on the lipid A as an antibiotic target and immune-therapeutic molecule, with a special attention on the crucial role of the chemical structure and its exploitation for conceiving novel strategies for treatment of several immune-related pathologies.
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Affiliation(s)
- Pilar Garcia-Vello
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy.
| | - Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy
| | - Daniele Zucchetta
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Alla Zamyatina
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Cristina De Castro
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy.
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5
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González-Fernández C, Bringas E, Oostenbrink C, Ortiz I. In silico investigation and surmounting of Lipopolysaccharide barrier in Gram-Negative Bacteria: How far has molecular dynamics Come? Comput Struct Biotechnol J 2022; 20:5886-5901. [PMID: 36382192 PMCID: PMC9636410 DOI: 10.1016/j.csbj.2022.10.039] [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: 08/26/2022] [Revised: 10/24/2022] [Accepted: 10/24/2022] [Indexed: 11/29/2022] Open
Abstract
Lipopolysaccharide (LPS), a main component of the outer membrane of Gram-negative bacteria, has crucial implications on both antibiotic resistance and the overstimulation of the host innate immune system. Fighting against these global concerns calls for the molecular understanding of the barrier function and immunostimulatory ability of LPS. Molecular dynamics (MD) simulations have become an invaluable tool for uncovering important findings in LPS research. While the reach of MD simulations for investigating the immunostimulatory ability of LPS has been already outlined, little attention has been paid to the role of MD simulations for exploring its barrier function and synthesis. Herein, we give an overview about the impact of MD simulations on gaining insight into the shield role and synthesis pathway of LPS, which have attracted considerable attention to discover molecules able to surmount antibiotic resistance, either circumventing LPS defenses or disrupting its synthesis. We specifically focus on the enhanced sampling and free energy calculation methods that have been combined with MD simulations to address such research. We also highlight the use of special-purpose MD supercomputers, the importance of appropriate LPS and ions parameterization to obtain reliable results, and the complementary views that MD and wet-lab experiments provide. Thereby, this work, which covers the last five years of research, apart from outlining the phenomena and strategies that are being explored, evidences the valuable insights that are gained by MD, which may be useful to advance antibiotic design, and what the prospects of this in silico method could be in LPS research.
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Affiliation(s)
- Cristina González-Fernández
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
| | - Eugenio Bringas
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
| | - Chris Oostenbrink
- Institute for Molecular Modeling and Simulation, BOKU – University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Inmaculada Ortiz
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
- Corresponding author.
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6
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González-Fernández C, Basauri A, Fallanza M, Bringas E, Oostenbrink C, Ortiz I. Fighting Against Bacterial Lipopolysaccharide-Caused Infections through Molecular Dynamics Simulations: A Review. J Chem Inf Model 2021; 61:4839-4851. [PMID: 34559524 PMCID: PMC8549069 DOI: 10.1021/acs.jcim.1c00613] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
![]()
Lipopolysaccharide
(LPS) is the primary component of the outer
leaflet of Gram-negative bacterial outer membranes. LPS elicits an
overwhelming immune response during infection, which can lead to life-threatening
sepsis or septic shock for which no suitable treatment is available
so far. As a result of the worldwide expanding multidrug-resistant
bacteria, the occurrence and frequency of sepsis are expected to increase;
thus, there is an urge to develop novel strategies for treating bacterial
infections. In this regard, gaining an in-depth understanding about
the ability of LPS to both stimulate the host immune system and interact
with several molecules is crucial for fighting against LPS-caused
infections and allowing for the rational design of novel antisepsis
drugs, vaccines and LPS sequestration and detection methods. Molecular
dynamics (MD) simulations, which are understood as being a computational
microscope, have proven to be of significant value to understand LPS-related
phenomena, driving and optimizing experimental research studies. In
this work, a comprehensive review on the methods that can be combined
with MD simulations, recently applied in LPS research, is provided.
We focus especially on both enhanced sampling methods, which enable
the exploration of more complex systems and access to larger time
scales, and free energy calculation approaches. Thereby, apart from
outlining several strategies for surmounting LPS-caused infections,
this work reports the current state-of-the-art of the methods applied
with MD simulations for moving a step forward in the development of
such strategies.
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Affiliation(s)
- Cristina González-Fernández
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
| | - Arantza Basauri
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
| | - Marcos Fallanza
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
| | - Eugenio Bringas
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
| | - Chris Oostenbrink
- Institute for Molecular Modeling and Simulation, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Inmaculada Ortiz
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
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Naïtaleb R, Denys A, Allain F, Ausseil J, Toumieux S, Kovensky J. Synthesis of new sulfated disaccharides for the modulation of TLR4-dependent inflammation. Org Biomol Chem 2021; 19:4346-4351. [PMID: 33908564 DOI: 10.1039/d1ob00692d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Natural sulfated glycans are key players in inflammation through TLR4 activation; therefore synthetic exogenous sulfated saccharides can be used to downregulate inflammation processes. We have designed and synthesized new sulfated compounds based on small and biocompatible carbohydrates that are able to cross the BBB. A suitable protected donor and acceptor, obtained from a unique precursor, have been stereoselectively glycosylated to give an orthogonally protected cellobiose disaccharide. Selective deprotection and sulfation allowed the syntheses of four differentially sulfated disaccharides, which have been characterized by NMR, HRMS and MS/MS. Together with their partially protected precursors, the new compounds were tested on HEK-TLR4 cells. Our results show the potential of small oligosaccharides to modulate TLR4 activity, confirming the need for sulfation and the key role of the 6-sulfate groups to trigger TLR4 signalization.
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Affiliation(s)
- Rachid Naïtaleb
- Laboratoire de Glycochimie, des Antimicrobiens et des Agroressources, LG2A CNRS UMR 7378, Université de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens, France.
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8
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Heine H, Adanitsch F, Peternelj TT, Haegman M, Kasper C, Ittig S, Beyaert R, Jerala R, Zamyatina A. Tailored Modulation of Cellular Pro-inflammatory Responses With Disaccharide Lipid A Mimetics. Front Immunol 2021; 12:631797. [PMID: 33815382 PMCID: PMC8012497 DOI: 10.3389/fimmu.2021.631797] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 02/17/2021] [Indexed: 01/08/2023] Open
Abstract
Pro-inflammatory signaling mediated by Toll-like receptor 4 (TLR4)/myeloid differentiation-2 (MD-2) complex plays a crucial role in the instantaneous protection against infectious challenge and largely contributes to recovery from Gram-negative infection. Activation of TLR4 also boosts the adaptive immunity which is implemented in the development of vaccine adjuvants by application of minimally toxic TLR4 activating ligands. The modulation of pro-inflammatory responses via the TLR4 signaling pathway was found beneficial for management of acute and chronic inflammatory disorders including asthma, allergy, arthritis, Alzheimer disease pathology, sepsis, and cancer. The TLR4/MD-2 complex can recognize the terminal motif of Gram-negative bacterial lipopolysaccharide (LPS)—a glycophospholipid lipid A. Although immense progress in understanding the molecular basis of LPS-induced TLR4-mediated signaling has been achieved, gradual, and predictable TLR4 activation by structurally defined ligands has not yet been attained. We report on controllable modulation of cellular pro-inflammatory responses by application of novel synthetic glycolipids—disaccharide-based lipid A mimetics (DLAMs) having picomolar affinity for TLR4/MD-2. Using crystal structure inspired design we have developed endotoxin mimetics where the inherently flexible β(1 → 6)-linked diglucosamine backbone of lipid A is replaced by a conformationally restricted α,α-(1↔1)-linked disaccharide scaffold. The tertiary structure of the disaccharide skeleton of DLAMs mirrors the 3-dimensional shape of TLR4/MD-2 bound E. coli lipid A. Due to exceptional conformational rigidity of the sugar scaffold, the specific 3D organization of DLAM must be preserved upon interaction with proteins. These structural factors along with specific acylation and phosphorylation pattern can ensure picomolar affinity for TLR4 and permit efficient dimerization of TLR4/MD-2/DLAM complexes. Since the binding pose of lipid A in the binding pocket of MD-2 (±180°) is crucial for the expression of biological activity, the chemical structure of DLAMs was designed to permit a predefined binding orientation in the binding groove of MD-2, which ensured tailored and species-independent (human and mice) TLR4 activation. Manipulating phosphorylation and acylation pattern at the sugar moiety facing the secondary dimerization interface allowed for adjustable modulation of the TLR4-mediated signaling. Tailored modulation of cellular pro-inflammatory responses by distinct modifications of the molecular structure of DLAMs was attained in primary human and mouse immune cells, lung epithelial cells and TLR4 transfected HEK293 cells.
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Affiliation(s)
- Holger Heine
- Research Group Innate Immunity, Research Center Borstel - Leibniz Lung Center, Airway Research Center North (ARCN), German Center for Lung Research (DZL), Borstel, Germany
| | - Florian Adanitsch
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Tina Tinkara Peternelj
- Department of Biotechnology, National Institute of Chemistry, University of Ljubljana, Ljubljana, Slovenia
| | - Mira Haegman
- Unit of Molecular Signal Transduction in Inflammation, Department of Biomedical Molecular Biology, Ghent University, Center for Inflammation Research, VIB, Ghent, Belgium
| | | | - Simon Ittig
- Biozentrum University of Basel, Basel, Switzerland
| | - Rudi Beyaert
- Unit of Molecular Signal Transduction in Inflammation, Department of Biomedical Molecular Biology, Ghent University, Center for Inflammation Research, VIB, Ghent, Belgium
| | - Roman Jerala
- Department of Biotechnology, National Institute of Chemistry, University of Ljubljana, Ljubljana, Slovenia
| | - Alla Zamyatina
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
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Zamyatina A, Heine H. Lipopolysaccharide Recognition in the Crossroads of TLR4 and Caspase-4/11 Mediated Inflammatory Pathways. Front Immunol 2020; 11:585146. [PMID: 33329561 PMCID: PMC7732686 DOI: 10.3389/fimmu.2020.585146] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 10/23/2020] [Indexed: 12/12/2022] Open
Abstract
The innate immune response to lipopolysaccharide is essential for host defense against Gram-negative bacteria. In response to bacterial infection, the TLR4/MD-2 complex that is expressed on the surface of macrophages, monocytes, dendritic, and epithelial cells senses picomolar concentrations of endotoxic LPS and triggers the production of various pro-inflammatory mediators. In addition, LPS from extracellular bacteria which is either endocytosed or transfected into the cytosol of host cells or cytosolic LPS produced by intracellular bacteria is recognized by cytosolic proteases caspase-4/11 and hosts guanylate binding proteins that are involved in the assembly and activation of the NLRP3 inflammasome. All these events result in the initiation of pro-inflammatory signaling cascades directed at bacterial eradication. However, TLR4-mediated signaling and caspase-4/11-induced pyroptosis are largely involved in the pathogenesis of chronic and acute inflammation. Both extra- and intracellular LPS receptors—TLR4/MD-2 complex and caspase-4/11, respectively—are able to directly bind the lipid A motif of LPS. Whereas the structural basis of lipid A recognition by the TLR4 complex is profoundly studied and well understood, the atomic mechanism of LPS/lipid A interaction with caspase-4/11 is largely unknown. Here we describe the LPS-induced TLR4 and caspase-4/11 mediated signaling pathways and their cross-talk and scrutinize specific structural features of the lipid A motif of diverse LPS variants that have been reported to activate caspase-4/11 or to induce caspase-4/11 mediated activation of NLRP3 inflammasome (either upon transfection of LPS in vitro or upon infection of cell cultures with intracellular bacteria or by LPS as a component of the outer membrane vesicles). Generally, inflammatory caspases show rather similar structural requirements as the TLR4/MD-2 complex, so that a “basic” hexaacylated bisphosphorylated lipid A architecture is sufficient for activation. However, caspase-4/11 can sense and respond to much broader variety of lipid A variants compared to the very “narrow” specificity of TLR4/MD-2 complex as far as the number and the length of lipid chains attached at the diglucosamine backbone of lipid A is concerned. Besides, modification of the lipid A phosphate groups with positively charged appendages such as phosphoethanolamine or aminoarabinose could be essential for the interaction of lipid A/LPS with inflammatory caspases and related proteins.
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Affiliation(s)
- Alla Zamyatina
- Institute of Organic Chemistry, Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Holger Heine
- Research Group Innate Immunity, Research Center Borstel-Leibniz Lung Center, Airway Research Center North (ARCN), German Center for Lung Disease (DZL), Borstel, Germany
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10
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Brandenburg K, Schromm AB, Weindl G, Heinbockel L, Correa W, Mauss K, Martinez de Tejada G, Garidel P. An update on endotoxin neutralization strategies in Gram-negative bacterial infections. Expert Rev Anti Infect Ther 2020; 19:495-517. [PMID: 33210958 DOI: 10.1080/14787210.2021.1834847] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Gram-negative bacterial infections represent still a severe problem of human health care, regarding the increase in multi-resistance against classical antibiotics and the lack of newly developed antimicrobials. For the fight against these germs, anti-infective agents must overcome and/or bind to the Gram-negative outer membrane consisting of a lipopolysaccharide (LPS, endotoxin) outer leaflet and an inner leaflet from phospholipids, with additional peripheral or integral membrane proteins (OMP's). AREAS COVERED The current article reviews data of existing therapeutic options and summarizes newer approaches for targeting and neutralizing endotoxins, ranging from in vitro over in vivo animal data to clinical applications by using databases such as Medline. EXPERT OPINION Conventional antibiotic treatment of the bacteria leads to their killing, but not necessary LPS neutralization, which may be a severe problem in particular for the systemic pathway. This is the reason why there is an increasing number of therapeutic approaches, which - besides combating whole bacteria - at the same time try to neutralize endotoxin within or outside the bacterial cells mainly responsible for the high inflammation induction in Gram-negative species.
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Affiliation(s)
- Klaus Brandenburg
- Brandenburg Antiinfektiva GmbH, c/o Forschungszentrum Borstel, Borstel, Germany
| | - Andra B Schromm
- FG Immunobiophysik, Forschungszentrum Borstel, Leibniz Lungenzentrum, Borstel, Germany
| | - Günther Weindl
- Brandenburg Antiinfektiva GmbH, c/o Forschungszentrum Borstel, Borstel, Germany.,Universität Bonn, Universität Bonn Pharmazeutisches Institut Pharmakologie Und Toxikologie Bonn, Germany
| | - Lena Heinbockel
- Brandenburg Antiinfektiva GmbH, c/o Forschungszentrum Borstel, Borstel, Germany
| | - Wilmar Correa
- FG Biophysik, Forschungszentrum Borstel, Leibniz Lungenzentrum, Borstel, Germany
| | - Karl Mauss
- Brandenburg Antiinfektiva GmbH, c/o Forschungszentrum Borstel, Borstel, Germany.,Asklepios-Klinik Hamburg-Altona, Hamburg, Germany
| | - Guillermo Martinez de Tejada
- Department of Microbiology and Parasitology, University of Navarra, E-31008 Pamplona, Spain and Navarra Institute for Health Research (Idisna), Pamplona, Spain.,Department de Microbiologia, Universidad De Navarra, Pamplona, Spain
| | - Patrick Garidel
- Martin-Luther-Universität Halle-Wittenberg, Institut für Chemie, Halle/Saale, Germany
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11
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Romerio A, Peri F. Increasing the Chemical Variety of Small-Molecule-Based TLR4 Modulators: An Overview. Front Immunol 2020; 11:1210. [PMID: 32765484 PMCID: PMC7381287 DOI: 10.3389/fimmu.2020.01210] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/15/2020] [Indexed: 12/17/2022] Open
Abstract
Toll-Like Receptor 4 (TLR4) is one of the receptors of innate immunity. It is activated by Pathogen- and Damage-Associated Molecular Patterns (PAMPs and DAMPs) and triggers pro-inflammatory responses that belong to the repertoire of innate immune responses, consequently protecting against infectious challenges and boosting adaptive immunity. Mild TLR4 stimulation by non-toxic molecules resembling its natural agonist (lipid A) provided efficient vaccine adjuvants. The non-toxic TLR4 agonist monophosphoryl lipid A (MPLA) has been approved for clinical use. This suggests the development of other TLR4 agonists as adjuvants or drugs for cancer immunotherapy. TLR4 excessive activation by a Gram-negative bacteria lipopolysaccharide (LPS) leads to sepsis, while TLR4 stimulation by DAMPs is a common mechanism in several inflammatory and autoimmune diseases. TLR4 inhibition by small molecules and antibodies could therefore provide access to innovative therapeutics targeting sepsis as well as acute and chronic inflammations. The potential use of TLR4 antagonists as anti-inflammatory drugs with unique selectivity and a new mechanism of action compared to corticosteroids or other non-steroid anti-inflammatory drugs fueled the search for compounds of natural or synthetic origin able to block or inhibit TLR4 activation and signaling. The wide spectrum of clinical settings to which TLR4 inhibitors can be applied include autoimmune diseases (rheumatoid arthritis, inflammatory bowel diseases), vascular inflammation, neuroinflammations, and neurodegenerative diseases. The last advances (from 2017) in TLR4 activation or inhibition by small molecules (molecular weight <2 kDa) are reviewed here. Studies on pre-clinical validation of new chemical entities (drug hits) on cellular or animal models as well as new clinical studies on previously developed TLR4 modulators are reported. Innovative TLR4 modulators discovered by computer-assisted drug design and an artificial intelligence approach are described. Some "old" TLR4 agonists or antagonists such as MPLA or Eritoran are under study for repositioning in different pharmacological contexts. The mechanism of action of the molecules and the level of TLR4 involvement in their biological activity are critically discussed.
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Affiliation(s)
- Alessio Romerio
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Francesco Peri
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
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Guo X, Chen J. The protective effects of saxagliptin against lipopolysaccharide (LPS)-induced inflammation and damage in human dental pulp cells. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2019; 47:1288-1294. [PMID: 30942641 DOI: 10.1080/21691401.2019.1596925] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Bacteria play a pivotal role in the pathological initiation and progression of pulpitis. Lipopolysaccharide (LPS) is recognized as a major component of the outer wall of Gram-negative bacteria. Saxagliptin, a potent inhibitor of dipeptidyl peptidase-4 (DPP-4), has been licensed for the treatment of type 2 diabetes. In this study, we aimed to evaluate the protective effects of saxagliptin against LPS-induced intracellular insults in human dental pulp cells (HDPCs). We found that DPP-4 is expressed in HDPCs. Interestingly, the expression of DPP-4 was increased in response to LPS treatment. We also found that saxagliptin ameliorated LPS-induced production of ROS and reduction of glutathione (GSH). Additionally, saxagliptin prevented LPS-induced mitochondrial dysfunction by increasing the levels of mitochondrial membrane potential (MMP) and the production of adenosine triphosphate (ATP). Importantly, saxagliptin ameliorated LPS-induced reduction of cell viability and lactate dehydrogenase (LDH) release. Our results indicate that saxagliptin significantly inhibited LPS-induced expression and secretions of tumour necrosis factor alpha (TNF-α), interleukin (IL)-1β and IL-6 in HDPCs. Mechanistically, we found that saxagliptin inhibited the phosphorylation of p38 and the activation of NF-κB. Our findings suggest that saxagliptin might have a potential therapeutic capacity for the treatment of pulpitis through mitigating inflammatory signalling in dental pulp cells.
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Affiliation(s)
- Xinxing Guo
- a Department of orthodontics , Jinan Stomatological Hospital , Jinan , PR China
| | - Jing Chen
- b Department of Emergency, School of Stomatology , Shandong University , Jinan , PR China
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Liu X, Cao Y, Zhang Y, Sun B, Liang H. Teneligliptin inhibits lipopolysaccharide-induced cytotoxicity and inflammation in dental pulp cells. Int Immunopharmacol 2019; 73:57-63. [PMID: 31078926 DOI: 10.1016/j.intimp.2019.04.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 04/17/2019] [Accepted: 04/28/2019] [Indexed: 12/22/2022]
Abstract
Diabetes mellitus is one of the most common health threatening disorders. Patients with chronic diabetes are at high risk of contracting oral diseases, including dental pulp damage. In this study, we reviewed how Teneligliptin, a commonly used anti-diabetic agent, protected dental pulp cells from lipopolysaccharide (LPS)-induced cytotoxicity and improved their viability. The dental pulp cells treated with Teneligliptin were resistant to LPS-induced reactive oxygen species (ROS) and its byproduct 4-hydroxynonenal (4-HNE) generation. The Teneligliptin recovered LPS-induced a reduction of cellular glutathione and produced cytokine including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). Mechanistically, we found that Teneligliptin suppressed LPS- that caused an expression of the cell surface receptor toll like receptor 4 (TLR-4) and the activation of JNK kinase and activator protein 1 (AP1) as well as the nuclear factor-κB (NF-κB) signal pathways. Collectively, our study demonstrates that the molecular mechanism Teneligliptin is a protective anti-diabetic agent in dental pulp cells and it has the potential to treat diabetes-associated dental pulp diseases.
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Affiliation(s)
- Xin Liu
- Department of Stomatology, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130033, China
| | - Yan Cao
- Department of Stomatology, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130033, China
| | - Yan Zhang
- Department of Stomatology, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130033, China
| | - Baozhen Sun
- Department of Hepatopancreatobiliary Surgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130033, China.
| | - Haiying Liang
- Department of Blood Transfusion, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130033, China.
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