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Zheng Y, Gao Y, Zhu W, Bai XG, Qi J. Advances in molecular agents targeting toll-like receptor 4 signaling pathways for potential treatment of sepsis. Eur J Med Chem 2024; 268:116300. [PMID: 38452729 DOI: 10.1016/j.ejmech.2024.116300] [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: 01/23/2024] [Accepted: 03/01/2024] [Indexed: 03/09/2024]
Abstract
Sepsis is a systemic inflammatory response syndrome caused by an infection. Toll-like receptor 4 (TLR4) is activated by endogenous molecules released by injured or necrotic tissues. Additionally, TLR4 is remarkably sensitive to infection of various bacteria and can rapidly stimulate host defense responses. The TLR4 signaling pathway plays an important role in sepsis by activating the inflammatory response. Accordingly, as part of efforts to improve the inflammatory response and survival rate of patients with sepsis, several drugs have been developed to regulate the inflammatory signaling pathways mediated by TLR4. Inhibition of TLR4 signal transduction can be directed toward either TLR4 directly or other proteins in the TLR4 signaling pathway. Here, we review the advances in the development of small-molecule agents and peptides targeting regulation of the TLR4 signaling pathway, which are characterized according to their structural characteristics as polyphenols, terpenoids, steroids, antibiotics, anthraquinones, inorganic compounds, and others. Therefore, regulating the expression of the TLR4 signaling pathway and modulating its effects has broad prospects as a target for the treatment of lung, liver, kidneys, and other important organs injury in sepsis.
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Affiliation(s)
- Yunyun Zheng
- Medicine College of Pingdingshan University, Pingdingshan, Henan, 467000, China
| | - Yingying Gao
- Medicine College of Pingdingshan University, Pingdingshan, Henan, 467000, China
| | - Weiru Zhu
- Medicine College of Pingdingshan University, Pingdingshan, Henan, 467000, China
| | - Xian-Guang Bai
- Medicine College of Pingdingshan University, Pingdingshan, Henan, 467000, China.
| | - Jinxu Qi
- Medicine College of Pingdingshan University, Pingdingshan, Henan, 467000, China.
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2
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McRae SA, Richards CM, Da Silva DE, Riar I, Yang SS, Zurfluh NE, Gibon J, Klegeris A. Pro-neuroinflammatory and neurotoxic potential of extracellular histones H1 and H3. Neurosci Res 2024:S0168-0102(24)00008-7. [PMID: 38278218 DOI: 10.1016/j.neures.2024.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 12/23/2023] [Accepted: 01/17/2024] [Indexed: 01/28/2024]
Abstract
Histones organize DNA within cellular nuclei, but they can be released from damaged cells. In peripheral tissues extracellular histones act as damage-associated molecular patterns (DAMPs) inducing pro-inflammatory activation of immune cells. Limited studies have considered DAMP-like activity of histones in the central nervous system (CNS); therefore, we studied the effects of extracellular histones on microglia, the CNS immunocytes, and on neuronal cells. Both the linker histone H1 and the core histone H3 induced pro-inflammatory activation of microglia-like cells by upregulating their secretion of NO and cytokines, including interferon-γ-inducible protein 10 (IP-10) and tumor necrosis factor-α (TNF). The selective inhibitors MMG-11 and TAK-242 were used to demonstrate involvement of toll-like receptors (TLR) 2 and 4, respectively, in H1-induced NO secretion by BV-2 microglia. H1, but not H3, downregulated the phagocytic activity of BV-2 microglia. H1 was also directly toxic to all neuronal cell types studied. We conclude that H1, and to a lesser extent H3, when released extracellularly, have the potential to act as a CNS DAMPs. Inhibition of the DAMP-like effects of extracellular histones on microglia and their neurotoxic activity represents a potential strategy for combating neurodegenerative diseases that are characterized by the adverse activation of microglia and neuronal death.
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Affiliation(s)
- Seamus A McRae
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada
| | - Christy M Richards
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada
| | - Dylan E Da Silva
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada
| | - Ishvin Riar
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada
| | - Sijie Shirley Yang
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada
| | - Noah E Zurfluh
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada
| | - Julien Gibon
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
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Khalaf JK, Bess LS, Walsh LM, Ward JM, Johnson CL, Livesay MT, Jackson KJ, Evans JT, Ryter KT, Bazin-Lee HG. Diamino Allose Phosphates: Novel, Potent, and Highly Stable Toll-like Receptor 4 Agonists. J Med Chem 2023; 66:13900-13917. [PMID: 37847244 DOI: 10.1021/acs.jmedchem.3c00724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Most known synthetic toll-like receptor 4 (TLR4) agonists are carbohydrate-based lipid-A mimetics containing several fatty acyl chains, including a labile 3-O-acyl chain linked to the C-3 position of the non-reducing sugar known to undergo cleavage impacting stability and resulting in loss of activity. To overcome this inherent instability, we rationally designed a new class of chemically more stable synthetic TLR4 ligands that elicit robust innate and adaptive immune responses. This new class utilized a diamino allose phosphate (DAP) scaffold containing a nonhydrolyzable 3-amide bond instead of the classical 3-ester. Accordingly, the DAPs have significantly improved thermostability in aqueous formulations and potency relative to other known natural and synthetic TLR4 ligands. Furthermore, the DAP analogues function as potent vaccine adjuvants to enhance influenza-specific antibodies in mice and provide protection against lethal influenza virus challenges. This novel set of TLR4 ligands show promise as next-generation vaccine adjuvants and stand-alone immunomodulators.
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Affiliation(s)
- Juhienah K Khalaf
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Laura S Bess
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Lois M Walsh
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Janine M Ward
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Craig L Johnson
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Mark T Livesay
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Konner J Jackson
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Jay T Evans
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Kendal T Ryter
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
| | - Hélène G Bazin-Lee
- Inimmune Corporation, 1121 E Broadway, Suite 121, Missoula, Montana 59802, United States
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Borio A, Holgado A, Passegger C, Strobl H, Beyaert R, Heine H, Zamyatina A. Exploring Species-Specificity in TLR4/MD-2 Inhibition with Amphiphilic Lipid A Mimicking Glycolipids. Molecules 2023; 28:5948. [PMID: 37630200 PMCID: PMC10459247 DOI: 10.3390/molecules28165948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 07/28/2023] [Accepted: 08/01/2023] [Indexed: 08/27/2023] Open
Abstract
The Toll-like receptor 4 (TLR4)/myeloid differentiation factor 2 (MD-2) complex is a key receptor of the innate immune system and a major driver of inflammation that is responsible for the multifaceted defense response to Gram-negative infections. However, dysfunction in the tightly regulated mechanisms of TLR4-mediated signaling leads to the uncontrolled upregulation of local and systemic inflammation, often resulting in acute or chronic disease. Therefore, the TLR4/MD-2 receptor complex is an attractive target for the design and development of anti-inflammatory therapies which aim to control the unrestrained activation of TLR4-mediated signaling. Complex structure-activity relationships and species-specificity behind ligand recognition by the TLR4/MD-2 complex complicate the development of MD-2-specific TLR4 antagonists. The restriction of the conformational flexibility of the disaccharide polar head group is one of the key structural features of the newly developed lipid A-mimicking glycophospholipids, which are potential inhibitors of TLR4-mediated inflammation. Since phosphorylation has a crucial influence on MD-2-ligand interaction, glycolipids with variable numbers and positioning of phosphate groups were synthesized and evaluated for their ability to inhibit TLR4-mediated pro-inflammatory signaling in human and murine immune cells. A bis-phosphorylated glycolipid was found to have nanomolar antagonist activity on human TLR4 while acting as a partial agonist on murine TLR4. The glycolipid inhibited mTLR4/MD-2-mediated cytokine release, acting as an antagonist in the presence of lipopolysaccharide (LPS), but at the same time induced low-level cytokine production.
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Affiliation(s)
- Alessio Borio
- Institute of Organic Chemistry, Department of Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Aurora Holgado
- Unit of Molecular Signal Transduction in Inflammation, VIB-UGent Center for Inflammation Research, Department for Biomedical Molecular Biology, Ghent University, Technologiepark 71, B-9052 Ghent, Belgium
| | - Christina Passegger
- Division of Immunology and Pathophysiology, Medical University Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Herbert Strobl
- Division of Immunology and Pathophysiology, Medical University Graz, Heinrichstraße 31, 8010 Graz, Austria
| | - Rudi Beyaert
- Unit of Molecular Signal Transduction in Inflammation, VIB-UGent Center for Inflammation Research, Department for Biomedical Molecular Biology, Ghent University, Technologiepark 71, B-9052 Ghent, Belgium
| | - Holger Heine
- Research Group Innate Immunity, Priority Area Chronic Lung Diseases, Research Center Borstel, Leibniz Lung Center, Airway Research Center North (ARCN), German Center for Lung Research (DZL), Parkallee 22, 23845 Borstel, Germany
| | - Alla Zamyatina
- Institute of Organic Chemistry, Department of Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
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Iwai R, Uchida S, Yamaguchi S, Nagata D, Koga A, Hayashi S, Yamamoto S, Miyasaka H. Effects of LPS from Rhodobacter sphaeroides, a Purple Non-Sulfur Bacterium (PNSB), on the Gene Expression of Rice Root. Microorganisms 2023; 11:1676. [PMID: 37512850 PMCID: PMC10383378 DOI: 10.3390/microorganisms11071676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/18/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
The effects of lipopolysaccharide (LPS) from Rhodobacter sphaeroides, a purple non-sulfur bacterium (PNSB), on the gene expression of the root of rice (Oryza sativa) were investigated by next generation sequencing (NGS) RNA-seq analysis. The rice seeds were germinated on agar plates containing 10 pg/mL of LPS from Rhodobacter sphaeroides NBRC 12203 (type culture). Three days after germination, RNA samples were extracted from the roots and analyzed by RNA-seq. The effects of dead (killed) PNSB cells of R. sphaeroides NBRC 12203T at the concentration of 101 cfu/mL (ca. 50 pg cell dry weight/mL) were also examined. Clean reads of NGS were mapped to rice genome (number of transcript ID: 44785), and differentially expressed genes were analyzed by DEGs. As a result of DEG analysis, 300 and 128 genes, and 86 and 8 genes were significantly up- and down-regulated by LPS and dead cells of PNSB, respectively. The plot of logFC (fold change) values of the up-regulated genes of LPS and PNSB dead cells showed a significant positive relationship (r2 = 0.6333, p < 0.0001), indicating that most of the effects of dead cell were attributed to those of LPS. Many genes related to tolerance against biotic (fungal and bacterial pathogens) and abiotic (cold, drought, and high salinity) stresses were up-regulated, and the most strikingly up-regulated genes were those involved in the jasmonate signaling pathway, and the genes of chalcone synthase isozymes, indicating that PNSB induced defense response against biotic and abiotic stresses via the jasmonate signaling pathway, despite the non-pathogenicity of PNSB.
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Affiliation(s)
- Ranko Iwai
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Shunta Uchida
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Sayaka Yamaguchi
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Daiki Nagata
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Aoi Koga
- Ciamo Co., Ltd., G-2F Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Shuhei Hayashi
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Shinjiro Yamamoto
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Hitoshi Miyasaka
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
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Miyasaka H, Koga A, Maki TA. Recent progress in the use of purple non-sulfur bacteria as probiotics in aquaculture. World J Microbiol Biotechnol 2023; 39:145. [PMID: 37014486 DOI: 10.1007/s11274-023-03592-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/23/2023] [Indexed: 04/05/2023]
Abstract
The use of probiotics in aquaculture is widely recognized as an ecological and cost-effective approach to raising healthy, pathogen-tolerant aquatic animals, including fish and shrimp. In particular for shrimp, probiotics are viewed as a promising countermeasure to the recent severe damage to the shrimp industry by bacterial and viral pathogens. Purple non-sulfur bacteria (PNSB) are Gram-negative, non-pathogenic bacteria with wide application potential in agriculture, wastewater treatment, and bioenergy/biomaterials production. In aquaculture, lactic bacteria and Bacillus are the major probiotic bacteria used, but PNSB, like Rhodopseudomonas and Rhodobacter, are also used. In this review, we summarize the previous work on the use of PNSB in aquaculture, overview the previous studies on the stimulation of innate immunity of shrimp by various probiotic microorganisms, and also share our results in the probiotic performance of Rhodovulum sulfidophilum KKMI01, a marine PNSB, which showed a superior effect in promotion of growth and stimulation of immunity in shrimp at a quite low concentration of 1 × 103 cfu (colony forming unit)/ml in rearing water.
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Affiliation(s)
- Hitoshi Miyasaka
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto, 860-0082, Japan.
- Ciamo Co. Ltd., G-2F Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto, 860-0082, Japan.
- Matsumoto Institute of Microorganisms Co. Ltd, 2904 Niimura, Matsumoto, Nagano, 390-1241, Japan.
| | - Aoi Koga
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto, 860-0082, Japan
- Ciamo Co. Ltd., G-2F Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto, 860-0082, Japan
- Matsumoto Institute of Microorganisms Co. Ltd, 2904 Niimura, Matsumoto, Nagano, 390-1241, Japan
| | - Taka-Aki Maki
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto, 860-0082, Japan
- Ciamo Co. Ltd., G-2F Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto, 860-0082, Japan
- Matsumoto Institute of Microorganisms Co. Ltd, 2904 Niimura, Matsumoto, Nagano, 390-1241, Japan
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TLR4 and MD2 variation among horses with differential TNFα baseline concentrations and response to intravenous lipopolysaccharide infusion. Sci Rep 2023; 13:1486. [PMID: 36707633 PMCID: PMC9883502 DOI: 10.1038/s41598-023-27956-y] [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: 09/15/2022] [Accepted: 01/10/2023] [Indexed: 01/28/2023] Open
Abstract
Gram-negative bacterial septicemia is mediated through binding of lipopolysaccharide (LPS) to mammalian toll-like receptor protein 4 (TLR4). TLR4 and its cognate protein, myeloid differentiation factor 2 (MD2) form a heterodimeric complex after binding LPS. This complex induces a cascade of reactions that results in increased proinflammatory cytokine gene expression, including TNFα, which leads to activation of innate immunity. In horses, the immune response to LPS varies widely. To determine if this variation is due to differences in TLR4 or MD2, DNA from 15 healthy adult horses with different TNFα dynamics after experimental intravenous LPS infusion was sequenced across exons of TLR4 and MD2. Haplotypes were constructed for both genes using all identified variants. Four haplotypes were observed for each gene. No significant associations were found between either TNFα baseline concentrations or response to LPS and haplotype; however, there was a significant association (P value = 0.0460) between the baseline TNFα concentration and one MD2 missense variant. Three-dimensional structures of the equine TLR4-MD2-LPS complex were built according to haplotype combinations observed in the study horses, and the implications of missense variants on LPS binding were modeled. Although the sample size was small, there was no evidence that variation in TLR4 or MD2 explains the variability in TNFα response observed after LPS exposure in horses.
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Zhu Z, Rahman Z, Aamir M, Shah SZA, Hamid S, Bilawal A, Li S, Ishfaq M. Insight into TLR4 receptor inhibitory activity via QSAR for the treatment of Mycoplasma pneumonia disease. RSC Adv 2023; 13:2057-2069. [PMID: 36712602 PMCID: PMC9833105 DOI: 10.1039/d2ra06178c] [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: 10/01/2022] [Accepted: 12/14/2022] [Indexed: 01/13/2023] Open
Abstract
Mycoplasma pneumoniae (MP) is one of the most common pathogenic organisms causing upper and lower respiratory tract infections, lung injury, and even death in young children. Toll-like receptors (TLRs) play an important role in innate immunity by allowing the host to recognize pathogens invading the body. Previous studies demonstrated that TLR4 is a potential therapeutic target for the treatment of MP pneumonia. Therefore, the present study aimed to screen biologically active ingredients that target the TLR4 receptor pathway. We first used molecular docking to screen out the active compounds inhibiting the TLR4 pathway, and then used regression and classification machine learning algorithms to establish a quantitative structure-activity relationship (QSAR) model to predict the biological activity of the screened compounds. A total of 78 molecules were used in QSAR modelling, which were retrieved from the ChEMBL database. The QSAR models had acceptable correlation coefficients of R 2 on the training and testing dataset in the range of 0.96 to 0.91 and 0.93 to 0.76, respectively. The multiclass classification models showed accuracy on training and testing data within ranges of 1.0 to 0.70, 0.96 to 0.63, and log loss ranges from 0.27 to 8.63, respectively. In addition, molecular descriptors and fingerprints have been studied as structural elements involved in increased and decreased inhibitory activities. These results provide a quantitative analysis of QSAR and classification models applicable for high-throughput screening, as well as insights into the mechanisms of inhibition of TLR4 antagonists.
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Affiliation(s)
- Zemin Zhu
- College of Computer Science, Huanggang Normal UniversityHuanggang 438000China+86 15972855212
| | - Ziaur Rahman
- College of Computer Science, Huanggang Normal UniversityHuanggang 438000China+86 15972855212
| | - Muhammad Aamir
- College of Computer Science, Huanggang Normal UniversityHuanggang 438000China+86 15972855212
| | - Syed Zahid Ali Shah
- Department of Pathology, Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur-PakistanPakistan
| | - Sattar Hamid
- The University of Agriculture PeshawarKhyber Pakhtunkhwa25130Pakistan
| | - Akhunzada Bilawal
- College of Food Science, Northeast Agricultural UniversityHarbinChina
| | - Sihong Li
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F UniversityHangzhou 311300China
| | - Muhammad Ishfaq
- College of Computer Science, Huanggang Normal UniversityHuanggang 438000China+86 15972855212
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Lee HH, Shin JS, Chung KS, Kim JM, Jung SH, Yoo HS, Hassan AHE, Lee JK, Inn KS, Lee S, Kim NJ, Lee KT. 3',4'-Dihydroxyflavone mitigates inflammatory responses by inhibiting LPS and TLR4/MD2 interaction. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2023; 109:154553. [PMID: 36610153 DOI: 10.1016/j.phymed.2022.154553] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/04/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND We previously reported the potential inhibitory activity of 3',4'-dihydroxyflavone (DHF) on nitric oxide (NO) and prostaglandin E2 (PGE2) production in lipopolysaccharide (LPS)-stimulated macrophages. PURPOSE We investigated the underlying molecular mechanisms of DHF in LPS-activated macrophages and evaluated its effect on LPS-induced septic shock in mice. METHODS To explore the anti-inflammatory effect of DHF, nitrite, PGE2, and cytokines were measured in vitro and in vivo experiments. In addition, to verify the molecular signaling pathway, quantitative real time-PCR, luciferase assay, nuclear extraction, electrophoretic mobility shift assay, immunocytochemistry, immunoprecipitation, molecular docking analysis, and myeloid differentiation 2 (MD2)-LPS binding assay were conducted. RESULTS DHF suppressed the LPS-induced expression of proinflammatory mediators through nuclear factor-κB (NF-κB), activator protein-1 (AP-1), and interferon regulatory factor 3 (IRF3) inactivation pathways in RAW 264.7 macrophages. Importantly, molecular docking analysis and in vitro binding assays showed that DHF interacts with the hydrophobic pocket of MD2 and then interferes with the interaction between LPS and toll-like receptor 4 (TLR4). DHF inhibited LPS-induced oxidative stress by upregulating nuclear factor erythroid 2-related factor 2 (Nrf2). Treatment of LPS-induced endotoxemia mice with DHF reduced the expression levels of pro-inflammatory mediators via the inactivation of NF-κB, AP-1, and signal transducer and activator of transcription 1 (STAT1) in the lung tissue, thus increasing the survival rate. CONCLUSION Taken together, our data first time revealed the underlying mechanism of the DHF-dependent anti-inflammatory effect by preventing LPS from binding to the TLR4/MD2 complex. Therefore, DHF may be a possible anti-inflammatory agent for the treatment of LPS-mediated inflammatory diseases.
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Affiliation(s)
- Hwi-Ho Lee
- Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02247, Republic of Korea
| | - Ji-Sun Shin
- Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02247, Republic of Korea
| | - Kyung-Sook Chung
- Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02247, Republic of Korea
| | - Jae-Min Kim
- Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02247, Republic of Korea; Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, Kyung Hee University, Seoul 02247, Republic of Korea
| | - Seang-Hwan Jung
- Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02247, Republic of Korea; Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, Kyung Hee University, Seoul 02247, Republic of Korea
| | - Hyung-Seok Yoo
- College of Pharmacy, Kyung Hee University, Seoul 02247, Republic of Korea
| | - Ahmed H E Hassan
- Medicinal Chemistry Laboratory, Department of Pharmacy, College of Pharmacy, Kyung Hee University, Seoul 02247, Republic of Korea; Department of Medicinal Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt
| | - Jong Kil Lee
- Department of Fundamental Pharmaceutical Science, Graduate School, Kyung Hee University, Seoul 02247, Republic of Korea
| | - Kyung-Soo Inn
- Department of Pharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul 02247, Republic of Korea
| | - Sangmin Lee
- College of Pharmacy, Kyung Hee University, Seoul 02247, Republic of Korea
| | - Nam-Jung Kim
- College of Pharmacy, Kyung Hee University, Seoul 02247, Republic of Korea.
| | - Kyung-Tae Lee
- Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02247, Republic of Korea.
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10
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Iwai R, Uchida S, Yamaguchi S, Sonoda F, Tsunoda K, Nagata H, Nagata D, Koga A, Goto M, Maki TA, Hayashi S, Yamamoto S, Miyasaka H. Effects of Seed Bio-Priming by Purple Non-Sulfur Bacteria (PNSB) on the Root Development of Rice. Microorganisms 2022; 10:2197. [PMID: 36363789 PMCID: PMC9698004 DOI: 10.3390/microorganisms10112197] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/01/2022] [Accepted: 11/03/2022] [Indexed: 07/30/2023] Open
Abstract
The effects of seed bio-priming (seed soaking) with purple non-sulfur bacteria (PNSB) on the grain productivity and root development of rice were examined by a field study and laboratory experiments, respectively. Two PNSB strains, Rhodopseudomonas sp. Tsuru2 and Rhodobacter sp. Tsuru3, isolated from the paddy field of the study site were used for seed bio-priming. For seed bio-priming in the field study, the rice seeds were soaked for 1 day in water containing a 1 × 105 colony forming unit (cfu)/mL of PNSB cells, and the rice grain productivities at the harvest time were 420, 462 and 504 kg/are for the control, strain Tsuru2-primed, and strain Tsuru3-primed seeds, respectively. The effects of seed priming on the root development were examined with cell pot cultivation experiments for 2 weeks. The total root length, root surface area, number of tips and forks were evaluated with WinRhizo, an image analysis system, and strains Tsuru2- and Tsuru3-primed seeds showed better root development than the control seeds. The effects of seed priming with the dead (killed) PNSB cells were also examined, and the seed priming with the dead cells was also effective, indicating that the effects were attributed to some cellular components. We expected the lipopolysaccharide (LPS) of PNSB as the effective component of PNSB and found that seed priming with LPS of Rhodobacter sphaeroides NBRC 12203 (type culture) at the concentrations of 5 ng/mL and 50 ng/mL enhanced the root development.
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Affiliation(s)
- Ranko Iwai
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Shunta Uchida
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Sayaka Yamaguchi
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Fumika Sonoda
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Kana Tsunoda
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Hiroto Nagata
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Daiki Nagata
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Aoi Koga
- Ciamo Co., Ltd., Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Midori Goto
- Ciamo Co., Ltd., Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Taka-aki Maki
- Matsumoto Institute of Microorganisms Co., Ltd., 2904 Niimura, Matsumoto, Nagano 390-1241, Japan
| | - Shuhei Hayashi
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Shinjiro Yamamoto
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
| | - Hitoshi Miyasaka
- Department of Applied Life Science, Sojo University, 4-22-1 Ikeda, Nishiku, Kumamoto 860-0082, Japan
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11
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Franco-Trepat E, Alonso-Pérez A, Guillán-Fresco M, Jorge-Mora A, Crespo-Gomar A, López-Fagúndez M, Pazos-Pérez A, Gualillo O, Belén Bravo S, Gómez R. Amitriptyline blocks innate immune responses mediated by TLR4 & IL1R: preclinical and clinical evidence in OA and gout. Br J Pharmacol 2021; 179:270-286. [PMID: 34643941 PMCID: PMC9300168 DOI: 10.1111/bph.15707] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 08/10/2021] [Accepted: 09/09/2021] [Indexed: 11/28/2022] Open
Abstract
Background and Purpose Osteoarthritis, a major cause of disability in developed countries does not have effective treatment. Activation of TLR4 and innate immune response factors contribute to osteoarthritis progressive cartilage degradation. There are no clinically available TLR4 inhibitors. Interestingly, the antidepressant amitriptyline could block this receptor. Thus, we evaluated amitriptyline anti‐TLR4 effects on human osteoarthritis chondrocytes in order to repurpose it as an inhibitor of innate immune response in joint inflammatory pathologies. Experimental Approach Using in silico docking analysis, RT‐PCR, siRNA, elisa, proteomics and clinical data mining of drug consumption, we explored the clinical relevance of amitriptyline blockade of TLR4‐mediated innate immune responses in human osteoarthritis chondrocytes. Key Results Amitriptyline bound TLR4 but not IL‐1 receptor. Interestingly, amitriptyline binding to TLR4 inhibited TLR4‐ and IL‐1 receptor‐mediated innate immune responses in human osteoarthritis chondrocytes, synoviocytes and osteoblasts cells. Amitriptyline reduced basal innate immune responses and promoted anabolic effects in human osteoarthritis chondrocytes. Supporting its anti‐innate immune response effects, amitriptyline down‐regulated basal and induced expression of NLRP3, an inflammasome member from IL‐1 receptor signalling linked to osteoarthritis and gout pathologies. Accordingly, mining of dissociated and aggregated drug consumption data from 107,172 elderly patients (>65 years) revealed that amitriptyline consumption was significantly associated with lower colchicine consumption associated with inflammatory gout flare treatment. Conclusion and Implications Amitriptyline blocks TLR4‐, IL‐1 receptor and NLRP3‐dependent innate immune responses. This together with clinical data amitriptyline could be repurposed for systemic or local innate immune response management in diverse joint inflammatory pathologies.
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Affiliation(s)
- Eloi Franco-Trepat
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Ana Alonso-Pérez
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - María Guillán-Fresco
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Alberto Jorge-Mora
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Antia Crespo-Gomar
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Miriam López-Fagúndez
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Andrés Pazos-Pérez
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Oreste Gualillo
- NEIRID LAB, Institute IDIS, SERGAS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Susana Belén Bravo
- Proteomics Unit, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Rodolfo Gómez
- Musculoskeletal Pathology Group, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
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12
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β-(1→4)-Mannobiose Acts as an Immunostimulatory Molecule in Murine Dendritic Cells by Binding the TLR4/MD-2 Complex. Cells 2021; 10:cells10071774. [PMID: 34359943 PMCID: PMC8305851 DOI: 10.3390/cells10071774] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/05/2021] [Accepted: 07/08/2021] [Indexed: 12/18/2022] Open
Abstract
Some β-mannans, including those in coffee bean and soy, contain a mannose backbone with β-(1→4) bonds. Such mannooligosaccharides could have immunological functions involving direct interaction with immune cells, in addition to acting as prebiotics. This study aimed at assessing the immunological function of mannooligosaccharides with β-(1→4) bond, and elucidating their mechanism of action using bone marrow-derived murine dendritic cells (BMDCs). When BMDCs were stimulated with the mannooligosaccharides, only β-Man-(1→4)-Man significantly induced production of cytokines that included IL-6, IL-10, TNF-α, and IFN-β, and enhanced CD4+ T-cell stimulatory capacity. Use of putative receptor inhibitors revealed the binding of β-Man-(1→4)-Man to TLR4/MD2 complex and involvement with the complement C3a receptor (C3aR) for BMDC activation. Interestingly, β-Man-(1→4)-Man prolonged the production of pro-inflammatory cytokines (IL-6 and TNF-α), but not of the IL-10 anti-inflammatory cytokine during extended culture of BMDCs, associated with high glucose consumption. The results suggest that β-Man-(1→4)-Man is an immunostimulatory molecule, and that the promotion of glycolysis could be involved in the production of pro-inflammatory cytokine in β-Man-(1→4)-Man-stimulated BMDCs. This study could contribute to development of immune-boosting functional foods and a novel vaccine adjuvant.
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13
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Okechukwu CC, Pirro NT, Chappell MC. Evidence that angiotensin II does not directly stimulate the MD2-TLR4 innate inflammatory pathway. Peptides 2021; 136:170436. [PMID: 33181267 PMCID: PMC7855779 DOI: 10.1016/j.peptides.2020.170436] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/22/2020] [Accepted: 10/27/2020] [Indexed: 12/11/2022]
Abstract
The renin-angiotensin system (RAS) plays a critical role in the regulation of blood pressure. Inappropriate activation of the RAS, particularly stimulation of the ACE-Ang II-AT1 receptor axis is a key factor in hypertension and AT1R antagonists (ARBs) are first line therapies in the treatment of cardiovascular disease (CVD). Accumulating evidence suggests that the Ang II-AT1R axis may stimulate both innate and adaptive immune systems. Indeed, recent studies suggest that Ang II stimulates inflammatory events in an AT1R-independent manner by binding the MD2 accessory protein of the TLR4 complex in renal NRK-52E cells. Direct Ang II stimulation of the TLR4 complex is clinically relevant as ARBs increase circulating Ang II levels. Thus, the current study further investigated Ang II stimulation of the TLR4 pathway to release of the pro-inflammatory cytokine CCL2 under identical conditions to the TLR4 ligands LPS and palmitate in the NRK-52E cells. Although LPS (1 ng/mL) and palmitate (100 μM) stimulated CCL2 release 20-fold, Ang II (0.1-10 μM) failed to induce CCL2 release. Both the LPS and palmitate CCL2 responses were abolished by the TLR4 inhibitor Tak242 and significantly reduced by the MD2 inhibitor L48H37. Ang II (1 μM) had no additive effects on LPS (1 ng/mL) or palmitate (100 μM), and the ARB candesartan failed to attenuate CCL2 release to either agent alone. Ang II also failed to induce the release of the putative TLR4 ligand HMBG1. These studies failed to confirm that Ang II directly stimulates the MD2-TLR4 complex to induce cytokine release in NRK-52E cells.
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Affiliation(s)
- Charles C Okechukwu
- Hypertension & Vascular Research Center, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Nancy T Pirro
- Hypertension & Vascular Research Center, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Mark C Chappell
- Hypertension & Vascular Research Center, Wake Forest University School of Medicine, Winston-Salem, NC, USA.
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14
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XU Z, YIN N, REN R, RUAN Z. In silico analysis based on constituents of the medicinal plant Xuebijing (XBJ) to identify candidate treatment agents for sepsis in the omics-driven research era. MINERVA BIOTECNOL 2021. [DOI: 10.23736/s1120-4826.20.02684-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Yang Y, Hu Y, Zhou Y, Liang T, Tang H, Ju H, Shi Q, Fang H. Lys694Arg polymorphism leads to blunted responses to LPS by interfering TLR4 with recruitment of MyD88. Innate Immun 2020; 27:483-492. [PMID: 32513051 PMCID: PMC8504268 DOI: 10.1177/1753425920927479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
TLR4 polymorphisms such as Asp299Gly and Thr399Ile related to Gram-negative sepsis have been reported to result in significantly blunted responsiveness to LPS. Our study group previously screened other TLR4 polymorphic variants by checking the NF-κB activation in comparison to wild type (WT) TLR4 in human embryonic kidney 293T cells. In this study, we found that the Lys694Arg (K694R) polymorphism reduced the activation of NF-κB, and the production of downstream inflammatory factors IL-1, TNF-α and IL-6, representing the K694R polymorphism, led to blunted responsiveness to LPS. Then, we examined the influence of the K694R polymorphism on total and cell-surface TLR4 expression by Western blotting and flow cytometry, respectively, but observed no differences between the K694R polymorphism and WT TLR4. We also used co-immunoprecipitation to determine the interaction of the K694R polymorphism and WT TLR4 with their co-receptor myeloid differentiation factor 2 (MD2) and their downstream signal adaptor MyD88. We found that K694R reduced the recruitment of MyD88 in TLR4 signalling but had no impact on the interaction with MD2.
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Affiliation(s)
- Yajie Yang
- Department of Anaesthesiology, Jinshan Hospital, Fudan University, PR China
| | - Yan Hu
- Department of Anaesthesiology, Zhongshan Hospital, Fudan University, PR China
| | - Yile Zhou
- Department of Anaesthesiology, Jinshan Hospital, Fudan University, PR China
| | - Tao Liang
- Department of Anaesthesiology, Jinshan Hospital, Fudan University, PR China
| | - Haihong Tang
- Department of Anaesthesiology, Jinshan Hospital, Fudan University, PR China
| | - Huihui Ju
- Department of Anaesthesiology, Zhongshan Hospital, Fudan University, PR China
| | - Qiqing Shi
- Department of Anaesthesiology, Minhang Branch, Zhongshan Hospital, Fudan University, PR China
| | - Hao Fang
- Department of Anaesthesiology, Zhongshan Hospital, Fudan University, PR China.,Department of Anaesthesiology, Minhang Branch, Zhongshan Hospital, Fudan University, PR China
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16
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Lin TL, Shu CC, Chen YM, Lu JJ, Wu TS, Lai WF, Tzeng CM, Lai HC, Lu CC. Like Cures Like: Pharmacological Activity of Anti-Inflammatory Lipopolysaccharides From Gut Microbiome. Front Pharmacol 2020; 11:554. [PMID: 32425790 PMCID: PMC7212368 DOI: 10.3389/fphar.2020.00554] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/14/2020] [Indexed: 12/13/2022] Open
Abstract
Gut microbiome maintains local gut integrity and systemic host homeostasis, where optimal control of intestinal lipopolysaccharides (LPS) activity may play an important role. LPS mainly produced from gut microbiota are a group of lipid-polysaccharide chemical complexes existing in the outer membrane of Gram-negative bacteria. Traditionally, LPS mostly produced from Proteobacteria are well known for their ability in inducing strong inflammatory responses (proinflammatory LPS, abbreviated as P-LPS), leading to septic shock or even death in animals and humans. Although the basic structures and chemical properties of P-LPS derived from different bacterial species generally show similarity, subtle and differential immune activation activities are observed. On the other hand, frequently ignored, a group of LPS molecules mainly produced by certain microbiota bacteria such as Bacteroidetes show blunt or even antagonistic activity in initiating pro-inflammatory responses (anti-inflammatory LPS, abbreviated as A-LPS). In this review, besides the immune activation properties of P-LPS, we also focus on the description of anti-inflammatory effects of A-LPS, and their potential antagonistic mechanism. We address the possibility of using native or engineered A-LPS for immune modulation in prevention or even treatment of P-LPS induced chronic inflammation related diseases. Understanding the exquisite interactive relationship between structure-activity correlation of P- and A-LPS not only contributes to molecular understanding of immunomodulation and homeostasis, but also re-animates the development of novel LPS-based pharmacological strategy for prevention and therapy of chronic inflammation related diseases.
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Affiliation(s)
- Tzu-Lung Lin
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Microbiota Research Center and Emerging Viral Infections Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Chin-Chung Shu
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Young-Mao Chen
- Bachelor Degree Program in Marine Biotechnology, College of Life Sciences, National Taiwan Ocean University, Keelung, Taiwan
| | - Jang-Jih Lu
- Department of Laboratory Medicine, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Ting-Shu Wu
- Division of Infectious Diseases, Department of Internal Medicine, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Wei-Fan Lai
- Department of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chi-Meng Tzeng
- School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Hsin-Chih Lai
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Microbiota Research Center and Emerging Viral Infections Research Center, Chang Gung University, Taoyuan, Taiwan.,Central Research Laboratory, Xiamen Chang Gung Allergology Consortium, Xiamen Chang Gung Hospital, Xiamen, China.,Research Center for Chinese Herbal Medicine and Research Center for Food and Cosmetic Safety, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
| | - Chia-Chen Lu
- Department of Chest Medicine, Internal Medicine, Fu Jen Catholic University Hospital, Fu Jen Catholic University, New Taipei City, Taiwan.,Department of Respiratory Therapy, Fu Jen Catholic University, New Taipei City, Taiwan
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17
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Magrone T, Jirillo E, Magrone M, Russo MA, Romita P, Massari F, Foti C. Red Grape Polyphenol Oral Administration Improves Immune Response in Women Affected by Nickel-Mediated Allergic Contact Dermatitis. Endocr Metab Immune Disord Drug Targets 2020; 21:374-384. [PMID: 32167433 DOI: 10.2174/1871530320666200313152648] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/10/2020] [Accepted: 01/17/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Our previous findings demonstrated that in vitro supplementation of polyphenols, extracted from seeds of red grape (Nero di Troia cultivar), to peripheral lymphomonocytes from patients affected by allergic contact dermatitis (ACD) to nickel (Ni) could reduce the release of proinflammatory cytokines and nitric oxide (NO), while increasing the levels of interleukin (IL)-10, an anti-inflammatory cytokine. OBJECTIVE To assess whether an intervention with oral administration of polyphenols leads to a reduction of peripheral biomarkers in ACD patients. METHODS At T0, 25 patients affected by ACD to Ni were orally administered with 300 mg polyphenols prodie extracted from seeds of red grape (Nero di Troia cultivar) (NATUR-OX®) for 3 months (T1). The other 25 patients affected by ACD to Ni received placebo only for the same period of time. Serum biomarkers were analyzed at T0 and T1. In both groups, seven dropouts were recorded. RESULTS At T1 in comparison to T0, in treated patients, values of interferon-γ, IL-4, IL-17, pentraxin 3 and NO decreased, while IL-10 levels increased when compared with T0 values. Conversely, in placebo- treated patients, no modifications of biomarkers were evaluated at T1. CONCLUSION Present laboratory data rely on the anti-oxidant, anti-inflammatory and anti-allergic properties of polyphenols.
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Affiliation(s)
- Thea Magrone
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, School of Medicine, University of Bari, Bari, Italy
| | - Emilio Jirillo
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, School of Medicine, University of Bari, Bari, Italy
| | - Manrico Magrone
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, School of Medicine, University of Bari, Bari, Italy
| | - Matteo A Russo
- MEBIC Consortium, San Raffaele Open University of Rome and IRCCS San Raffaele Pisana of Rome, Rome, Italy
| | - Paolo Romita
- Department of Biomedical Sciences and Human Oncology, University of Bari, School of Medicine, University of Bari, Bari, Italy
| | - Francesco Massari
- Department of Biomedical Sciences and Human Oncology, University of Bari, School of Medicine, University of Bari, Bari, Italy
| | - Caterina Foti
- Department of Biomedical Sciences and Human Oncology, University of Bari, School of Medicine, University of Bari, Bari, Italy
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18
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Wang Z, Gu Z, Hou Q, Chen W, Mu D, Zhang Y, Liu Q, Liu Z, Yang D. Zebrafish GSDMEb Cleavage-Gated Pyroptosis Drives Septic Acute Kidney Injury In Vivo. THE JOURNAL OF IMMUNOLOGY 2020; 204:1929-1942. [PMID: 32111733 DOI: 10.4049/jimmunol.1901456] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 01/30/2020] [Indexed: 02/06/2023]
Abstract
The bacteria LPS is one of the leading endotoxins responsible for sepsis; its sensing pathway-induced pyroptosis plays an important role in innate immunity. However, excessive pyroptosis might cause immunological diseases, even multiple organ failure and death by undefined mechanisms. Given that the development of acute kidney injury (AKI) in patients with sepsis causes significant morbidity and mortality, the mechanism of pyroptosis in regulating septic AKI remains unknown. In this study, we establish a zebrafish crispant in vivo analysis model and reveal that both caspy2 and gasdermin Eb (GSDMEb) contribute to lethal LPS-induced septic shock. Meanwhile, the in vitro analysis reveals that caspy2 activation can specifically cleave GSDMEb to release its N terminus to mediate pyroptosis, which functions as GSDMD in mammals. Interestingly, we establish an in vivo propidium iodide-staining method and reveal that the caspy2-GSDMEb signaling cascade is essential for enhancing renal tubular damage during lethal LPS-induced septic shock, whereas administration of the zebrafish-specific GSDMEb-derived peptide inhibitor Ac-FEID-CMK can attenuate mortality and septic AKI in vivo. Moreover, we confirm that either caspase-11 or GSDMD deficiency decreases both inflammatory cytokines and kidney dysfunction enzyme release and prolongs survival in a murine model of septic shock. Taken together, these findings demonstrate an evolutionary executor for pyroptosis in zebrafish and reveal that the pyroptosis of renal tubular cells is a major cause of septic AKI, and also provide an ideal in vivo screening model for potential antisepsis therapeutic strategies.
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Affiliation(s)
- Zhuang Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Zhaoyan Gu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Qing Hou
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China
| | - Weijie Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Di Mu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yuanxing Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.,Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China; and
| | - Qin Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.,Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China; and.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
| | - Zhihong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China
| | - Dahai Yang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; .,Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai 200237, China; and
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19
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Ruan D, Liu W, Shi Y, Tan M, Yang L, Wang Z, Zhou Y, Wang R. Protective Effects of Aqueous Extract of Radix Isatidis on Lipopolysaccharide-Induced Sepsis in C57BL/6J Mice. J Med Food 2019; 23:79-89. [PMID: 31765267 DOI: 10.1089/jmf.2019.4476] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Endotoxic shock exhibits a considerably high mortality risk. It is defined as a systemic inflammatory response syndrome caused by a microbial infection. Radix Isatidis has anti-inflammatory, antiviral, and antipyretic effects and is used worldwide. This study investigated the antiendotoxin sepsis effects of an aqueous R. Isatidis extract (RIE) and explored the possible pharmacological molecular mechanisms. Male C57BL/6J mice were intravenously injected with 15 mg/kg lipopolysaccharide (LPS) to induce endotoxic shock. The results demonstrated that the survival rate of mice pretreated with RIE increased, and LPS-induced liver and lung damage were reduced by inhibiting inflammation. For elucidating detailed molecular mechanisms, we focused on LPS-induced transcription factors: nuclear factor-κB (NF-κB) and interferon regulatory factor 3 (IRF3). Our results demonstrated that the protective effects of RIE were strongly dependent on IRF3-induced interferon-β, not on NF-κB-induced tumor necrosis factor-α and interleukin-1β. In addition, RIE suppressed the phosphorylation of IRF3, not NF-κB. In conclusion, this study revealed the antiendotoxic properties of RIE on LPS-induced sepsis and provided mechanistic evidence for the beneficial effects of RIE.
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Affiliation(s)
- Deqing Ruan
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Wenjing Liu
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yanhong Shi
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SUTCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Menghui Tan
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Li Yang
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SUTCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,Shanghai R&D Centre for Standardization of Chinese Medicines, Shanghai, China
| | - Zhengtao Wang
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SUTCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,Shanghai R&D Centre for Standardization of Chinese Medicines, Shanghai, China
| | - Yue Zhou
- The MOE Key Laboratory for Standardization of Chinese Medicines and The SUTCM Key Laboratory for New Resources and Quality Evaluation of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Rui Wang
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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20
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Leitner GR, Wenzel TJ, Marshall N, Gates EJ, Klegeris A. Targeting toll-like receptor 4 to modulate neuroinflammation in central nervous system disorders. Expert Opin Ther Targets 2019; 23:865-882. [PMID: 31580163 DOI: 10.1080/14728222.2019.1676416] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Introduction: Adverse immune activation contributes to many central nervous system (CNS) disorders. All main CNS cell types express toll-like receptor 4 (TLR 4). This receptor is critical for a myriad of immune functions such as cytokine secretion and phagocytic activity of microglia; however, imbalances in TLR 4 activation can contribute to the progression of neurodegenerative diseases. Areas covered: We considered available evidence implicating TLR 4 activation in the following CNS pathologies: Alzheimer's disease, Parkinson's disease, ischemic stroke, traumatic brain injury, multiple sclerosis, multiple systems atrophy, and Huntington's disease. We reviewed studies reporting effects of TLR 4-specific antagonists and agonists in models of peripheral and CNS diseases from the perspective of possible future use of TLR 4 ligands in CNS disorders. Expert opinion: TLR 4-specific antagonists could suppress neuroinflammation by reducing overproduction of inflammatory mediators; however, they may interfere with protein clearance mechanisms and myelination. Agonists that specifically activate myeloid differentiation primary-response protein 88 (MyD88)-independent pathway of TLR 4 signaling could facilitate beneficial glial phagocytic activity with limited activity as inducers of proinflammatory mediators. Deciphering the disease stage-specific involvement of TLR 4 in CNS pathologies is crucial for the future clinical development of TLR 4 agonists and antagonists.
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Affiliation(s)
- Gunnar R Leitner
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Tyler J Wenzel
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Nick Marshall
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Ellen J Gates
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
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21
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Anderson JA, Loes AN, Waddell GL, Harms MJ. Tracing the evolution of novel features of human Toll-like receptor 4. Protein Sci 2019; 28:1350-1358. [PMID: 31075178 DOI: 10.1002/pro.3644] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/07/2019] [Accepted: 05/08/2019] [Indexed: 12/13/2022]
Abstract
Toll-like receptor 4 (TLR4) is a critical innate immune protein that activates inflammation in response to extracellular cues. Much of the work to understand how the protein works in humans has been done using mouse models. Although human and mouse TLR4 have many shared features, they have also diverged significantly since their last common ancestor, acquiring 277 sequence differences. Functional differences include the extent of ligand-independent activation, whether lipid IVa acts as an antagonist or agonist, and the relative species cross-compatibility of their MD-2 cofactor. We set out to understand the evolutionary origins for these functional differences between human and mouse TLR4. Using a combination of phylogenetics, ancestral sequence reconstruction, and functional characterization, we found that evolutionary changes to the human TLR4, rather than changes to the mouse TLR4, were largely responsible for these functional changes. Human TLR4 repressed ancestral ligand-independent activity and gained antagonism to lipid IVa. Additionally, mutations to the human TLR4 cofactor MD-2 led to lineage-specific incompatibility between human and opossum TLR4 complex members. These results were surprising, as mouse TLR4 has acquired many more mutations than human TLR4 since their last common ancestor. Our work has polarized this set of transitions and sets up work to study the mechanistic underpinnings for the evolution of new functions in TLR4.
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Affiliation(s)
- Jeremy A Anderson
- Institute for Molecular Biology, University of Oregon, Eugene, Oregon, 97403.,Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, 97403
| | - Andrea N Loes
- Institute for Molecular Biology, University of Oregon, Eugene, Oregon, 97403.,Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, 97403
| | - Grace L Waddell
- Institute for Molecular Biology, University of Oregon, Eugene, Oregon, 97403.,Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, 97403
| | - Michael J Harms
- Institute for Molecular Biology, University of Oregon, Eugene, Oregon, 97403.,Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, 97403
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22
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Korneev KV, Kondakova AN, Sviriaeva EN, Mitkin NA, Palmigiano A, Kruglov AA, Telegin GB, Drutskaya MS, Sturiale L, Garozzo D, Nedospasov SA, Knirel YA, Kuprash DV. Hypoacylated LPS from Foodborne Pathogen Campylobacter jejuni Induces Moderate TLR4-Mediated Inflammatory Response in Murine Macrophages. Front Cell Infect Microbiol 2018; 8:58. [PMID: 29535976 PMCID: PMC5835049 DOI: 10.3389/fcimb.2018.00058] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 02/12/2018] [Indexed: 11/13/2022] Open
Abstract
Toll-like receptor 4 (TLR4) initiates immune response against Gram-negative bacteria upon specific recognition of lipid A moiety of lipopolysaccharide (LPS), the major component of their cell wall. Some natural differences between LPS variants in their ability to interact with TLR4 may lead to either insufficient activation that may not prevent bacterial growth, or excessive activation which may lead to septic shock. In this study we evaluated the biological activity of LPS isolated from pathogenic strain of Campylobacter jejuni, the most widespread bacterial cause of foodborne diarrhea in humans. With the help of hydrophobic chromatography and MALDI-TOF mass spectrometry we showed that LPS from a C. jejuni strain O2A consists of both hexaacyl and tetraacyl forms. Since such hypoacylation can result in a reduced immune response in humans, we assessed the activity of LPS from C. jejuni in mouse macrophages by measuring its capacity to activate TLR4-mediated proinflammatory cytokine and chemokine production, as well as NFκB-dependent reporter gene transcription. Our data support the hypothesis that LPS acylation correlates with its bioactivity.
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Affiliation(s)
- Kirill V. Korneev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Immunology, Biological Faculty, Lomonosov Moscow State University, Moscow, Russia
| | - Anna N. Kondakova
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Ekaterina N. Sviriaeva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Immunology, Biological Faculty, Lomonosov Moscow State University, Moscow, Russia
| | - Nikita A. Mitkin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Angelo Palmigiano
- CNR Institute for Polymers Composites and Biomaterials, Catania, Italy
| | - Andrey A. Kruglov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- German Rheumatism Research Center, Leibniz Institute, Berlin, Germany
| | - Georgy B. Telegin
- Branch of Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Pushchino, Russia
| | - Marina S. Drutskaya
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Luisa Sturiale
- CNR Institute for Polymers Composites and Biomaterials, Catania, Italy
| | - Domenico Garozzo
- CNR Institute for Polymers Composites and Biomaterials, Catania, Italy
| | - Sergei A. Nedospasov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Immunology, Biological Faculty, Lomonosov Moscow State University, Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- German Rheumatism Research Center, Leibniz Institute, Berlin, Germany
| | - Yuriy A. Knirel
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Dmitry V. Kuprash
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Immunology, Biological Faculty, Lomonosov Moscow State University, Moscow, Russia
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23
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Loes AN, Bridgham JT, Harms MJ. Coevolution of the Toll-Like Receptor 4 Complex with Calgranulins and Lipopolysaccharide. Front Immunol 2018. [PMID: 29515592 PMCID: PMC5826337 DOI: 10.3389/fimmu.2018.00304] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Toll-like receptor 4 (TLR4) induces inflammation in response to both pathogen- and host-derived molecules. Lipopolysaccharide (LPS) recognition by TLR4 has been shown to occur across the amniotes, but endogenous signaling through TLR4 has not been validated outside of placental mammals. To determine whether endogenous danger signaling is also shared across amniotes, we studied the evolution of TLR4-activation by the calgranulin proteins (S100A8, S100A9, and S100A12), a clade of host molecules that potently activate TLR4 in placental mammals. We performed phylogenetic and syntenic analysis and found MRP-126—a gene in birds and reptiles—is likely orthologous to the mammalian calgranulins. We then used an ex vivo TLR4 activation assay to establish that calgranulin pro-inflammatory activity is not specific to placental mammals, but is also exhibited by representative marsupial and sauropsid species. This activity is strongly dependent on the cofactors CD14 and MD-2 for all species studied, suggesting a conserved mode of activation across the amniotes. Ortholog complementation experiments between the calgranulins, TLR4, CD14, and MD-2 revealed extensive lineage specific-coevolution and multi-way interactions between components that are necessary for the activation of NF-κB signaling by calgranulins and LPS. Our work demonstrates that calgranulin activation of TLR4 evolved at least ~320 million years ago and has been conserved in the amniote innate immune system.
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Affiliation(s)
- Andrea N Loes
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, United States.,Institute of Molecular Biology, University of Oregon, Eugene, OR, United States
| | - Jamie T Bridgham
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR, United States
| | - Michael J Harms
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, United States.,Institute of Molecular Biology, University of Oregon, Eugene, OR, United States
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24
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Zou Y, Qin F, Chen J, Meng J, Wei L, Wu C, Zhang Q, Wei D, Chen X, Wu H, Chen X, Dai S. sTLR4/MD-2 complex inhibits colorectal cancer in vitro and in vivo by targeting LPS. Oncotarget 2018; 7:52032-52044. [PMID: 27409669 PMCID: PMC5239533 DOI: 10.18632/oncotarget.10496] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 06/30/2016] [Indexed: 12/18/2022] Open
Abstract
Colorectal cancer (CRC) is aggressive and associated with TLR4-MD-2 signaling. Toll-like receptor 4 (TLR4) and myeloid differentiation protein 2 (MD-2) were highly expressed in human CRC. The soluble form of extracellular TLR4 domain (sTLR4) and MD-2 may have important roles in binding lipopolysaccharide (LPS). In this study, sTLR4 and MD-2 protein and prepared sTLR4/MD-2 complex were synthesized successfully to restrain LPS-TLR4/MD-2 activation by competing with cellular membrane TLR4 for binding LPS. The sTLR4/MD-2 complex can significantly attenuate LPS induced pro-inflammatory and migration cytokine production in vitro and in vivo, and inhibit the effect of LPS on the cell cycle, migration and invasion of human CRC cells in vitro. Administration of sTLR4/MD-2 complex protected mice from tumor both in xenograft and implantation metastasis model. The sTLR4/MD-2 complex treated mice had smaller tumor, less body weight loss and lower expression of inflammatory cytokines. Here, the azoxymethane/dextran sulfate sodium salt (AOM/DSS) murine model was used as an experimental platform to simulate the physiological and pathological processes of cancers associated with chronic intestinal inflammation. AOM/DSS-induced tumors were inhibited in mice treated by sTLR4/MD-2 complex. It is demonstrated in our study that sTLR4/MD-2 complex could inhibit CRC by competing with binding LPS, raising the complex's possibility of a new prevention agent against CRC.
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Affiliation(s)
- Yan Zou
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Fengxian Qin
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Jifei Chen
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Jie Meng
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Liuhua Wei
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Chunlin Wu
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Qiaoyun Zhang
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Dong Wei
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Xiang Chen
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Hao Wu
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Xiaoli Chen
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
| | - Shengming Dai
- Medical Science Laboratory, The Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou, Guangxi, 545005, P.R. China
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25
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Kaszowska M, Wojcik M, Siednienko J, Lugowski C, Lukasiewicz J. Structure-Activity Relationship of Plesiomonas shigelloides Lipid A to the Production of TNF-α, IL-1β, and IL-6 by Human and Murine Macrophages. Front Immunol 2017; 8:1741. [PMID: 29321776 PMCID: PMC5732152 DOI: 10.3389/fimmu.2017.01741] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 11/23/2017] [Indexed: 01/27/2023] Open
Abstract
Plesiomonas shigelloides is a Gram-negative bacterium that is associated with diarrheal disease in humans. Lipopolysaccharide (LPS) is the main surface antigen and virulence factor of this bacterium. The lipid A (LA) moiety of LPS is the main region recognized by target cells of immune system. Here, we evaluated the biological activities of P. shigelloides LA for their abilities to induce the productions of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) by human and murine macrophages [THP-1 macrophages and immortalized murine bone marrow-derived macrophages (iBMDM)]. Four native P. shigelloides LA preparations differing in their phosphoethanolamine (PEtn) substitution, length, number, and saturation of fatty acids were compared with Escherichia coli O55 LA. The bisphosphorylated, hexaacylated, and asymmetric forms of the P. shigelloides and E. coli LA molecules had similar activities in human and murine macrophages, indicating that shortening of the acyl chains in P. shigelloides LA had no effect on its in vitro activities. The PEtn decoration also had no impact on the interaction with the toll-like receptor 4/MD-2 receptor complex. The heptaacylated form of P. shigelloides LA decorated with 16:0 exhibited strong effect on proinflammatory activity, significantly decreasing the levels of all tested cytokines in both murine and human macrophages. Our results revealed that despite the presence of shorter acyl chains and an unsaturated acyl residue (16:1), the bisphosphorylated, hexaacylated, and asymmetric forms of P. shigelloides LA represent highly immunostimulatory structures.
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Affiliation(s)
- Marta Kaszowska
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
| | - Marta Wojcik
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
| | - Jakub Siednienko
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
| | - Czeslaw Lugowski
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland.,Department of Biotechnology and Molecular Biology, University of Opole, Opole, Poland
| | - Jolanta Lukasiewicz
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
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26
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Identification of generic and pathogen-specific cord blood monocyte transcriptomes reveals a largely conserved response in preterm and term newborn infants. J Mol Med (Berl) 2017; 96:147-157. [PMID: 29134255 DOI: 10.1007/s00109-017-1609-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/23/2017] [Accepted: 10/30/2017] [Indexed: 12/20/2022]
Abstract
Escherichia coli and Staphylococcus epidermidis are predominant causes of neonatal sepsis, particularly affecting preterm infants. Susceptibility to infection has been attributed to "immature" innate monocyte defences, but no studies have assessed global transcriptional responses of neonatal monocytes to these pathogens. Here, we aimed to identify and characterise the neonatal monocyte transcriptional responses to E. coli and S. epidermidis and the role of common modifiers such as gestational age (GA) and exposure to chorioamnionitis (a common complication of preterm birth) to better understand early life innate immune responses. RNA-sequencing was performed on purified cord blood monocytes from very preterm (< 32 weeks GA) and term infants (37-40 weeks GA) following standardised challenge with live S. epidermidis or E. coli. The major transcriptional changes induced by either pathogen were highly conserved between infant groups and stimuli, highlighting a common extant neonatal monocyte response to infection, largely mediated by TLR/NF-κB/TREM-1 signalling. In addition, we observed an activated interferon-centred immune response specific to stimulation with E. coli in both preterm and term infants. These data provide novel insights into the functionality of neonatal monocytes at birth and highlight potential pathways that could be targeted to reduce the harmful effects of bacterial-induced inflammation in sepsis. E. coli and S. epidermidis elicit common transcriptional changes in cord monocytes. The common transcriptional response is mediated by TLR/NF-κB/TREM-1 signalling. IFN genes are differentially regulated by E. coli and S. epidermidis in monocytes. These responses are largely unaffected by GA or exposure to chorioamnionitis. KEY MESSAGES E. coli and S. epidermidis elicit common transcriptional changes in cord monocytes. The common transcriptional response is mediated by TLR/NF-κB/TREM-1 signalling. IFN-genes are differentially regulated by E. coli and S. epidermidis in monocytes. These responses are largely unaffected by GA or exposure to chorioamnionitis.
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27
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The Role of Carbohydrates in the Lipopolysaccharide (LPS)/Toll-Like Receptor 4 (TLR4) Signalling. Int J Mol Sci 2017; 18:ijms18112318. [PMID: 29099761 PMCID: PMC5713287 DOI: 10.3390/ijms18112318] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/27/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022] Open
Abstract
The interactions between sugar-containing molecules from the bacteria cell wall and pattern recognition receptors (PRR) on the plasma membrane or cytosol of specialized host cells are the first molecular events required for the activation of higher animal’s immune response and inflammation. This review focuses on the role of carbohydrates of bacterial endotoxin (lipopolysaccharide, LPS, lipooligosaccharide, LOS, and lipid A), in the interaction with the host Toll-like receptor 4/myeloid differentiation factor 2 (TLR4/MD-2) complex. The lipid chains and the phosphorylated disaccharide core of lipid A moiety are responsible for the TLR4 agonist action of LPS, and the specific interaction between MD-2, TLR4, and lipid A are key to the formation of the activated complex (TLR4/MD-2/LPS)2, which starts intracellular signalling leading to nuclear factors activation and to production of inflammatory cytokines. Subtle chemical variations in the lipid and sugar parts of lipid A cause dramatic changes in endotoxin activity and are also responsible for the switch from TLR4 agonism to antagonism. While the lipid A pharmacophore has been studied in detail and its structure-activity relationship is known, the contribution of core saccharides 3-deoxy-d-manno-octulosonic acid (Kdo) and heptosyl-2-keto-3-deoxy-octulosonate (Hep) to TLR4/MD-2 binding and activation by LPS and LOS has been investigated less extensively. This review focuses on the role of lipid A, but also of Kdo and Hep sugars in LPS/TLR4 signalling.
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28
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Luo M, Hu L, Li D, Wang Y, He Y, Zhu L, Ren W. MD-2 regulates LPS-induced NLRP3 inflammasome activation and IL-1beta secretion by a MyD88/NF-κB-dependent pathway in alveolar macrophages cell line. Mol Immunol 2017; 90:1-10. [DOI: 10.1016/j.molimm.2017.06.035] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 06/18/2017] [Accepted: 06/19/2017] [Indexed: 11/30/2022]
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29
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John CM, Phillips NJ, Stein DC, Jarvis GA. Innate immune response to lipooligosaccharide: pivotal regulator of the pathobiology of invasive Neisseria meningitidis infections. Pathog Dis 2017; 75:3569603. [PMID: 28423169 DOI: 10.1093/femspd/ftx030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/11/2017] [Indexed: 01/05/2023] Open
Abstract
Infections due to Neisseria meningitidis afflict more than one million people worldwide annually and cause death or disability in many survivors. The clinical course of invasive infections has been well studied, but our understanding of the cause of differences in patient outcomes has been limited because these are dependent on multiple factors including the response of the host, characteristics of the bacteria and interactions between the host and the bacteria. The meningococcus is a highly inflammatory organism, and the lipooligosaccharide (LOS) on the outer membrane is the most potent inflammatory molecule it expresses due to the interactions of the lipid A moiety of LOS with receptors of the innate immune system. We previously reported that increased phosphorylation of hexaacylated neisserial lipid A is correlated with greater inflammatory potential. Here we postulate that variability in lipid A phosphorylation can tip the balance of innate immune responses towards homeostatic tolerance or proinflammatory signaling that affects adaptive immune responses, causing disease with meningitis only, or septicemia with or without meningitis, respectively. Furthermore, we propose that studies of the relationship between bacterial virulence and gene expression should consider whether genetic variation could affect properties of biosynthetic enzymes resulting in LOS structural differences that alter disease pathobiology.
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Affiliation(s)
- Constance M John
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA.,Department of Laboratory Medicine, University of California, San Francisco, CA 94143, USA
| | - Nancy J Phillips
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143, USA
| | - Daniel C Stein
- University of Maryland, Department of Cell Biology and Molecular Genetics, College Park, MD 20742 USA
| | - Gary A Jarvis
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA.,Department of Laboratory Medicine, University of California, San Francisco, CA 94143, USA
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30
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Watkins HC, Rappazzo CG, Higgins JS, Sun X, Brock N, Chau A, Misra A, Cannizzo JPB, King MR, Maines TR, Leifer CA, Whittaker GR, DeLisa MP, Putnam D. Safe Recombinant Outer Membrane Vesicles that Display M2e Elicit Heterologous Influenza Protection. Mol Ther 2017; 25:989-1002. [PMID: 28215994 DOI: 10.1016/j.ymthe.2017.01.010] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 01/02/2017] [Accepted: 01/06/2017] [Indexed: 01/10/2023] Open
Abstract
Recombinant, Escherichia coli-derived outer membrane vesicles (rOMVs), which display heterologous protein subunits, have potential as a vaccine adjuvant platform. One drawback to rOMVs is their lipopolysaccharide (LPS) content, limiting their translatability to the clinic due to potential adverse effects. Here, we explore a unique rOMV construct with structurally remodeled lipids containing only the lipid IVa portion of LPS, which does not stimulate human TLR4. The rOMVs are derived from a genetically engineered B strain of E. coli, ClearColi, which produces lipid IVa, and which was further engineered in our laboratory to hypervesiculate and make rOMVs. We report that rOMVs derived from this lipid IVa strain have substantially attenuated pyrogenicity yet retain high levels of immunogenicity, promote dendritic cell maturation, and generate a balanced Th1/Th2 humoral response. Additionally, an influenza A virus matrix 2 protein-based antigen displayed on these rOMVs resulted in 100% survival against a lethal challenge with two influenza A virus strains (H1N1 and H3N2) in mice with different genetic backgrounds (BALB/c, C57BL/6, and DBA/2J). Additionally, a two-log reduction of lung viral titer was achieved in a ferret model of influenza infection with human pandemic H1N1. The rOMVs reported herein represent a potentially safe and simple subunit vaccine delivery platform.
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Affiliation(s)
- Hannah C Watkins
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - C Garrett Rappazzo
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Jaclyn S Higgins
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Xiangjie Sun
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Nicole Brock
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Annie Chau
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Aditya Misra
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Joseph P B Cannizzo
- College of Agriculture and Life Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Michael R King
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Taronna R Maines
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Cynthia A Leifer
- Department of Microbiology and Immunology, Cornell University College of Veterinary Medicine, Ithaca, NY 14853, USA
| | - Gary R Whittaker
- Department of Microbiology and Immunology, Cornell University College of Veterinary Medicine, Ithaca, NY 14853, USA
| | - Matthew P DeLisa
- Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA
| | - David Putnam
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA; Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA.
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31
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Virzì GM, Clementi A, Brocca A, Ronco C. Endotoxin Effects on Cardiac and Renal Functions and Cardiorenal Syndromes. Blood Purif 2017; 44:314-326. [PMID: 29161706 DOI: 10.1159/000480424] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 08/10/2017] [Indexed: 01/03/2023]
Abstract
Gram-negative sepsis is a major cause of morbidity and mortality in critical ill patients. Recent findings in molecular biology and in signaling pathways have enhanced our understanding of its pathogenesis and opened up opportunities of innovative therapeutic approaches. Endotoxin plays a pivotal role in the pathogenesis of multi-organ dysfunction in the setting of gram-negative sepsis. Indeed, heart and kidney impairments seem to be induced by the release of circulating pro-inflammatory and pro-apoptotic mediators triggered by endotoxin interaction with immune cells. These molecules are responsible for cellular apoptosis, autophagy, cell cycle arrest, and microRNAs activation. Therefore, the early identification of sepsis-associated acute kidney injury and heart dysfunction may improve the patient clinical outcome. In this report, we will consider the role of endotoxin in the pathogenesis of sepsis, its effects on both cardiac and renal functions, and the interactions between these 2 systems in the setting of cardiorenal syndromes (CRS), particularly in CRS type 5. Finally, we will discuss the possible role of extracorporeal therapies in reducing endotoxin levels.
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Affiliation(s)
- Grazia Maria Virzì
- Department of Nephrology, Dialysis and Transplant, San Bortolo Hospital, Agrigento, Italy
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32
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Pizzuto M, Gangloff M, Scherman D, Gay NJ, Escriou V, Ruysschaert JM, Lonez C. Toll-like receptor 2 promiscuity is responsible for the immunostimulatory activity of nucleic acid nanocarriers. J Control Release 2016; 247:182-193. [PMID: 28040465 PMCID: PMC5312493 DOI: 10.1016/j.jconrel.2016.12.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/23/2016] [Indexed: 12/14/2022]
Abstract
Lipopolyamines (LPAs) are cationic lipids; they interact spontaneously with nucleic acids to form lipoplexes used for gene delivery. The main hurdle to using lipoplexes in gene therapy lies in their immunostimulatory properties, so far attributed to the nucleic acid cargo, while cationic lipids were considered as inert to the immune system. Here we demonstrate for the first time that di-C18 LPAs trigger pro-inflammatory responses through Toll-like receptor 2 (TLR2) activation, and this whether they are bound to nucleic acids or not. Molecular docking experiments suggest potential TLR2 binding modes reminiscent of bacterial lipopeptide sensing. The di-C18 LPAs share the ability of burying their lipid chains in the hydrophobic cavity of TLR2 and, in some cases, TLR1, at the vicinity of the dimerization interface; the cationic headgroups form multiple hydrogen bonds, thus crosslinking TLRs into functional complexes. Unravelling the molecular basis of TLR1 and TLR6-driven heterodimerization upon LPA binding underlines the highly collaborative and promiscuous ligand binding mechanism. The prevalence of non-specific main chain-mediated interactions demonstrates that potentially any saturated LPA currently used or proposed as transfection agent is likely to activate TLR2 during transfection. Hence our study emphasizes the urgent need to test the inflammatory properties of transfection agents and proposes the use of docking analysis as a preliminary screening tool for the synthesis of new non-immunostimulatory nanocarriers.
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Affiliation(s)
- Malvina Pizzuto
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Boulevard du Triomphe, 1050 Brussels, Belgium.
| | - Monique Gangloff
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, UK.
| | - Daniel Scherman
- CNRS, Unité de Technologies Chimiques et Biologiques pour la Santé (UTCBS), UMR 8258, F-75006 Paris, France; INSERM, UTCBS U 1022, F-75006 Paris, France; Université Paris Descartes, Sorbonne-Paris-Cité University, UTCBS, F-75006 Paris, France; Chimie ParisTech, PSL Research University, UTCBS, F-75005 Paris, France
| | - Nicholas J Gay
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, UK
| | - Virginie Escriou
- CNRS, Unité de Technologies Chimiques et Biologiques pour la Santé (UTCBS), UMR 8258, F-75006 Paris, France; INSERM, UTCBS U 1022, F-75006 Paris, France; Université Paris Descartes, Sorbonne-Paris-Cité University, UTCBS, F-75006 Paris, France; Chimie ParisTech, PSL Research University, UTCBS, F-75005 Paris, France
| | - Jean-Marie Ruysschaert
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Boulevard du Triomphe, 1050 Brussels, Belgium
| | - Caroline Lonez
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Boulevard du Triomphe, 1050 Brussels, Belgium; Department of Veterinary Medicine, University of Cambridge, Madingley Rd, Cambridge CB3 0ES, UK
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Cardiolipins Act as a Selective Barrier to Toll-Like Receptor 4 Activation in the Intestine. Appl Environ Microbiol 2016; 82:4264-78. [PMID: 27208127 DOI: 10.1128/aem.00463-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 05/01/2016] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED Intestinal homeostasis mechanisms must protect the host intestinal tissue from endogenous lipopolysaccharides (LPSs) produced by the intestinal microbiota. In this report, we demonstrate that murine intestinal fecal lipids effectively block Toll-like receptor 4 (TLR4) responses to naturally occurring Bacteroidetes sp. LPS. Cardiolipin (CL) represents a significant proportion of the total intestinal and fecal lipids and, furthermore, potently antagonizes TLR4 activation by reducing LPS binding at the lipopolysaccharide binding protein (LBP), CD14, and MD-2 steps of the TLR4 signaling pathway. It is further demonstrated that intestinal lipids and CL are less effective at neutralizing more potent Enterobacteriaceae-type LPS, which is enriched in feces obtained from mice with dextran sodium sulfate (DSS)-treated inflammatory bowel disease. The selective inhibition of naturally occurring LPS structures by intestinal lipids may represent a novel homeostasis mechanism that blocks LPS activation in response to symbiotic but not dysbiotic microbial communities. IMPORTANCE The guts of animals harbor a variety of Gram-negative bacteria associated with both states of intestinal health and states of disease. Environmental factors, such as dietary habits, can drive the microbial composition of the host animal's intestinal bacterial community toward a more pathogenic state. Both beneficial and harmful Gram-negative bacteria are capable of eliciting potentially damaging inflammatory responses from the host intestinal tissues via a lipopolysaccharide (LPS)-dependent pathway. Physical mucosal barriers and antibodies produced by the intestinal immune system protect against the undesired inflammatory effects of LPS, although it is unknown why some bacteria are more effective at overcoming the protective barriers than others. This report describes the discovery of a lipid-type protective barrier in the intestine that reduces the deleterious effects of LPSs from beneficial bacteria but is less effective in dampening the inflammatory effects of LPSs from harmful bacteria, providing a novel mechanistic insight into inflammatory intestinal disorders.
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Immuno-Stimulatory Activity of Escherichia coli Mutants Producing Kdo2-Monophosphoryl-Lipid A or Kdo2-Pentaacyl-Monophosphoryl-Lipid A. PLoS One 2015; 10:e0144714. [PMID: 26710252 PMCID: PMC4692390 DOI: 10.1371/journal.pone.0144714] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/23/2015] [Indexed: 01/01/2023] Open
Abstract
Lipid A is the active center of lipopolysaccharide which also known as endotoxin. Monophosphoryl-lipid A (MPLA) has less toxicity but retains potent immunoadjuvant activity; therefore, it can be developed as adjuvant for improving the strength and duration of the immune response to antigens. However, MPLA cannot be chemically synthesized and can only be obtained by hydrolyzing lipopolysaccharide (LPS) purified from Gram-negative bacteria. Purifying LPS is difficult and time-consuming and can damage the structure of MPLA. In this study, Escherichia coli mutant strains HWB01 and HWB02 were constructed by deleting several genes and integrating Francisella novicida gene lpxE into the chromosome of E. coli wild type strain W3110. Compared with W3110, HWB01 and HWB02 synthesized very short LPS, Kdo2-monophosphoryl-lipid A (Kdo2-MPLA) and Kdo2-pentaacyl-monophosphoryl-lipid A (Kdo2-pentaacyl-MPLA), respectively. Structural changes of LPS in the outer membranes of HWB01 and HWB02 increased their membrane permeability, surface hydrophobicity, auto-aggregation ability and sensitivity to some antibiotics, but the abilities of these strains to activate the TLR4/MD-2 receptor of HKE-Blue hTLR4 cells were deceased. Importantly, purified Kdo2-MPLA and Kdo2-pentaacyl-MPLA differed from wild type LPS in their ability to stimulate the mammalian cell lines THP-1 and RAW264.7. The purification of Kdo2-MPLA and Kdo2-pentaacyl-MPLA from HWB01 and HWB02, respectively, is much easier than the purification of LPS from W3110, and these lipid A derivatives could be important tools for developing future vaccine adjuvants.
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Korneev KV, Arbatsky NP, Molinaro A, Palmigiano A, Shaikhutdinova RZ, Shneider MM, Pier GB, Kondakova AN, Sviriaeva EN, Sturiale L, Garozzo D, Kruglov AA, Nedospasov SA, Drutskaya MS, Knirel YA, Kuprash DV. Structural Relationship of the Lipid A Acyl Groups to Activation of Murine Toll-Like Receptor 4 by Lipopolysaccharides from Pathogenic Strains of Burkholderia mallei, Acinetobacter baumannii, and Pseudomonas aeruginosa. Front Immunol 2015; 6:595. [PMID: 26635809 PMCID: PMC4655328 DOI: 10.3389/fimmu.2015.00595] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 11/06/2015] [Indexed: 11/13/2022] Open
Abstract
Toll-like receptor 4 (TLR4) is required for activation of innate immunity upon recognition of lipopolysaccharide (LPS) of Gram-negative bacteria. The ability of TLR4 to respond to a particular LPS species is important since insufficient activation may not prevent bacterial growth while excessive immune reaction may lead to immunopathology associated with sepsis. Here, we investigated the biological activity of LPS from Burkholderia mallei that causes glanders, and from the two well-known opportunistic pathogens Acinetobacter baumannii and Pseudomonas aeruginosa (causative agents of nosocomial infections). For each bacterial strain, R-form LPS preparations were purified by hydrophobic chromatography and the chemical structure of lipid A, an LPS structural component, was elucidated by HR-MALDI-TOF mass spectrometry. The biological activity of LPS samples was evaluated by their ability to induce production of proinflammatory cytokines, such as IL-6 and TNF, by bone marrow-derived macrophages. Our results demonstrate direct correlation between the biological activity of LPS from these pathogenic bacteria and the extent of their lipid A acylation.
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Affiliation(s)
- Kirill V Korneev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia ; Biological Faculty, Lomonosov Moscow State University , Moscow , Russia
| | - Nikolay P Arbatsky
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences , Moscow , Russia
| | - Antonio Molinaro
- Department of Chemical Sciences, Università di Napoli Federico II , Naples , Italy
| | - Angelo Palmigiano
- CNR Institute for Polymers Composites and Biomaterials , Catania , Italy
| | | | - Mikhail M Shneider
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences , Moscow , Russia
| | - Gerald B Pier
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School , Boston, MA , USA
| | - Anna N Kondakova
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences , Moscow , Russia
| | - Ekaterina N Sviriaeva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia ; Biological Faculty, Lomonosov Moscow State University , Moscow , Russia
| | - Luisa Sturiale
- CNR Institute for Polymers Composites and Biomaterials , Catania , Italy
| | - Domenico Garozzo
- CNR Institute for Polymers Composites and Biomaterials , Catania , Italy
| | - Andrey A Kruglov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia ; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University , Moscow , Russia
| | - Sergei A Nedospasov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia ; Biological Faculty, Lomonosov Moscow State University , Moscow , Russia ; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University , Moscow , Russia
| | - Marina S Drutskaya
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia
| | - Yuriy A Knirel
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences , Moscow , Russia
| | - Dmitry V Kuprash
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia ; Biological Faculty, Lomonosov Moscow State University , Moscow , Russia
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Lonez C, Irvine KL, Pizzuto M, Schmidt BI, Gay NJ, Ruysschaert JM, Gangloff M, Bryant CE. Critical residues involved in Toll-like receptor 4 activation by cationic lipid nanocarriers are not located at the lipopolysaccharide-binding interface. Cell Mol Life Sci 2015; 72:3971-82. [PMID: 25956320 PMCID: PMC4575701 DOI: 10.1007/s00018-015-1915-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 03/31/2015] [Accepted: 04/23/2015] [Indexed: 12/05/2022]
Abstract
DiC14-amidine is a cationic lipid that was originally designed as a lipid nanocarrier for nucleic acid transport, and turned out to be a Toll-like receptor 4 (TLR4) agonist as well. We found that while E. coli lipopolysaccharide (LPS) is a TLR4 agonist in all species, diC14-amidine nanoliposomes are full agonists for human, mouse and cat receptors but weak horse agonists. Taking advantage of this unusual species specificity, we used chimeric constructs based on the human and horse sequences and identified two regions in the human TLR4 that modulate the agonist activity of diC14-amidine. Interestingly, these regions lie outside the known LPS-binding domain. Competition experiments also support our hypothesis that diC14-amidine interacts primarily with TLR4 hydrophobic crevices located at the edges of the TLR4/TLR4* dimerization interface. We have characterized potential binding modes using molecular docking analysis and suggest that diC14-amidine nanoliposomes activate TLR4 by facilitating its dimerization in a process that is myeloid differentiation 2 (MD-2)-dependent and cluster of differentiation 14 (CD14)-independent. Our data suggest that TLR4 may be activated through binding at different anchoring points, expanding the repertoire of TLR4 ligands to non-MD-2-binding lipids.
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Affiliation(s)
- Caroline Lonez
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Brussels, Belgium.
| | - Kate L Irvine
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Malvina Pizzuto
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Brussels, Belgium
| | - Boris I Schmidt
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Brussels, Belgium
| | - Nick J Gay
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Jean-Marie Ruysschaert
- Structure and Function of Biological Membranes, Université Libre de Bruxelles, Brussels, Belgium
| | - Monique Gangloff
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Clare E Bryant
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
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Kertai MD, Li YJ, Ji Y, Qi W, Lombard FW, Shah SH, Kraus WE, Stafford-Smith M, Newman MF, Milano CA, Waldron N, Podgoreanu MV, Mathew JP. Genome-wide association study of new-onset atrial fibrillation after coronary artery bypass grafting surgery. Am Heart J 2015; 170:580-90.e28. [PMID: 26385043 DOI: 10.1016/j.ahj.2015.06.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 06/15/2015] [Indexed: 01/04/2023]
Abstract
BACKGROUND Postoperative atrial fibrillation (AF) is a potentially life-threatening complication after coronary artery bypass graft (CABG) surgery. Genetic predisposition may predict risk for developing postoperative AF. METHODS Study subjects underwent CABG surgery with cardiopulmonary bypass at Duke University Medical Center. In a discovery cohort of 877 individuals from the Perioperative Genetics and Safety Outcomes Study, we performed a genome-wide association study using a logistic regression model with a covariate adjustment for AF risk index. Single-nucleotide polymorphisms (SNPs) that met a P < 5 × 10(-5) were further tested using a replication dataset of 304 individuals from the CATHeterization GENetics biorepository, followed by meta-analysis. Potential pathways related to postoperative AF were identified through gene enrichment analysis using the top genome-wide association study SNPs (P < 10(-4)). RESULTS Nineteen SNPs met the a priori defined discovery threshold for replication, but only 3 met nominal significance (P < .05) in the CATHeterization GENetics group, with only one-rs10504554, in the intronic region in lymphocyte antigen 96 (LY96)-showing the same direction of the effect for postoperative AF (odds ratio [OR] 0.48, 95% CI 0.34-0.68, P = 2.9 × 10(-5) vs OR 0.55, 95% CI 0.31-0.99, P = .046) and strong overall association by meta-analysis (meta-P = 4.0 × 10(-6)). Gene enrichment analysis highlighted the role of LY96 in pathways of biologic relevance to activation and modulation of innate immune responses. Our analysis also showed potential association between LY96 and nuclear factor κ-B interaction and postoperative AF through their relevance to inflammatory signaling pathways. CONCLUSIONS In patients undergoing CABG surgery, we found genetic polymorphisms in LY96 associated with decreased risk of postoperative AF.
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Mattis DM, Chervin AS, Ranoa DR, Kelley SL, Tapping RI, Kranz DM. Studies of the TLR4-associated protein MD-2 using yeast-display and mutational analyses. Mol Immunol 2015; 68:203-12. [PMID: 26320630 DOI: 10.1016/j.molimm.2015.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 08/06/2015] [Accepted: 08/10/2015] [Indexed: 11/19/2022]
Abstract
Bacterial lipopolysaccharide (LPS) activates the innate immune system by forming a complex with myeloid differentiation factor 2 (MD-2) and Toll-like receptor 4 (TLR4), which is present on antigen presenting cells. MD-2 plays an essential role in this activation of the innate immune system as a member of the ternary complex, TLR4:MD-2:LPS. With the goal of further understanding the molecular details of the interaction of MD-2 with LPS and TLR4, and possibly toward engineering dominant negative regulators of the MD-2 protein, here we subjected MD-2 to a mutational analysis using yeast display. The approach included generation of site-directed alanine mutants, and ligand-driven selections of MD-2 mutant libraries. Our findings showed that: (1) proline mutations in the F119-K132 loop that binds LPS were strongly selected for enhanced yeast surface stability, (2) there was a preference for positive-charged side chains (R/K) at residue 120 for LPS binding, and negative-charged side chains (D/E) for TLR4 binding, (3) aromatic residues were strongly preferred at F119 and F121 for LPS binding, and (4) an MD-2 mutant (T84N/D101A/S118A/S120D/K122P) exhibited increased binding to TLR4 but decreased binding to LPS. These studies revealed the impact of specific residues and regions of MD-2 on the binding of LPS and TLR4, and they provide a framework for further directed evolution of the MD-2 protein.
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Affiliation(s)
- Daiva M Mattis
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Adam S Chervin
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Diana R Ranoa
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA
| | - Stacy L Kelley
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA
| | - Richard I Tapping
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA
| | - David M Kranz
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA.
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Wang Y, Shan X, Chen G, Jiang L, Wang Z, Fang Q, Liu X, Wang J, Zhang Y, Wu W, Liang G. MD-2 as the target of a novel small molecule, L6H21, in the attenuation of LPS-induced inflammatory response and sepsis. Br J Pharmacol 2015; 172:4391-405. [PMID: 26076332 DOI: 10.1111/bph.13221] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 05/27/2015] [Accepted: 06/06/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE Myeloid differentiation 2 (MD-2) recognizes LPS, which is required for TLR4 activation, and represents an attractive therapeutic target for severe inflammatory disorders. We previously found that a chalcone derivative, L6H21, could inhibit LPS-induced overexpression of TNF-α and IL-6 in macrophages. Here, we performed a series of biochemical experiments to investigate whether L6H21 specifically targets MD-2 and inhibits the interaction and signalling transduction of LPS-TLR4/MD-2. EXPERIMENTAL APPROACH The binding affinity of L6H21 to MD-2 protein was analysed using computer docking, surface plasmon resonance analysis, elisa, fluorescence measurements and flow cytometric analysis. The effects of L6H21 on MAPK and NF-κB signalling were determined using EMSA, fluorescence staining, Western blotting and immunoprecipitation. The anti-inflammatory effects of L6H21 were confirmed using elisa and RT-qPCR in vitro. The anti-inflammatory effects of L6H21 were also evaluated in septic C57BL/6 mice. KEY RESULTS Compound L6H21 inserted into the hydrophobic region of the MD-2 pocket, forming hydrogen bonds with Arg(90) and Tyr(102) in the MD-2 pocket. In vitro, L6H21 subsequently suppressed MAPK phosphorylation, NF-κB activation and cytokine expression in macrophages stimulated by LPS. In vivo, L6H21 pretreatment improved survival, prevented lung injury, decreased serum and hepatic cytokine levels in mice subjected to LPS. In addition, mice with MD-2 gene knockout were universally protected from the effects of LPS-induced septic shock. CONCLUSIONS AND IMPLICATIONS Overall, this work demonstrated that the new chalcone derivative, L6H21, is a potential candidate for the treatment of sepsis. More importantly, the data confirmed that MD-2 is an important therapeutic target for inflammatory disorders.
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Affiliation(s)
- Yi Wang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaoou Shan
- Department of Paediatrics, the Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Gaozhi Chen
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Lili Jiang
- Department of Paediatrics, the Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhe Wang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Qilu Fang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xing Liu
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jingying Wang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yali Zhang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Wencan Wu
- Department of Orbital and Oculoplastic Surgery, The Eye Hospital of Wenzhou Medical University, Wenzhou, China
| | - Guang Liang
- Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
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Wang Y, Shan X, Dai Y, Jiang L, Chen G, Zhang Y, Wang Z, Dong L, Wu J, Guo G, Liang G. Curcumin Analog L48H37 Prevents Lipopolysaccharide-Induced TLR4 Signaling Pathway Activation and Sepsis via Targeting MD2. J Pharmacol Exp Ther 2015; 353:539-50. [DOI: 10.1124/jpet.115.222570] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 04/09/2015] [Indexed: 01/07/2023] Open
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Abstract
Recent findings unexpectedly revealed that human TLR4 can be directly activated by nickel ions. This activation is due to the coordination of nickel by a cluster of histidine residues on the ectodomain of human TLR4, which is absent in most other species. We aimed to elucidate the role of MD-2 in the molecular mechanism of TLR4/MD-2 activation by nickel, as nickel binding site on TLR4 is remote from MD-2, which directly binds the endotoxin as the main pathological activator of TLR4. We identified MD-2 and TLR4 mutants which abolished TLR4/MD-2 receptor activation by endotoxin but could nevertheless be significantly activated by nickel, which acts in synergy with LPS. Human TLR4/MD-2 was also activated by cobalt ions, while copper and cadmium were toxic in the tested concentration range. Activation of TLR4 by cobalt required MD-2 and was abolished by human TLR4 mutations of histidine residues at positions 456 and 458. We demonstrated that activation of TLR4 by nickel and cobalt ions can trigger both the MyD88-dependent and the -independent pathway. Based on our results we propose that predominantly hydrophobic interactions between MD-2 and TLR4 contribute to the stabilization of the TLR4/MD-2/metal ion complex in a conformation that enables activation.
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Oblak A, Pohar J, Jerala R. MD-2 determinants of nickel and cobalt-mediated activation of human TLR4. PLoS One 2015; 10:e0120583. [PMID: 25803856 PMCID: PMC4372398 DOI: 10.1371/journal.pone.0120583] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 01/24/2015] [Indexed: 11/19/2022] Open
Abstract
Recent findings unexpectedly revealed that human TLR4 can be directly activated by nickel ions. This activation is due to the coordination of nickel by a cluster of histidine residues on the ectodomain of human TLR4, which is absent in most other species. We aimed to elucidate the role of MD-2 in the molecular mechanism of TLR4/MD-2 activation by nickel, as nickel binding site on TLR4 is remote from MD-2, which directly binds the endotoxin as the main pathological activator of TLR4. We identified MD-2 and TLR4 mutants which abolished TLR4/MD-2 receptor activation by endotoxin but could nevertheless be significantly activated by nickel, which acts in synergy with LPS. Human TLR4/MD-2 was also activated by cobalt ions, while copper and cadmium were toxic in the tested concentration range. Activation of TLR4 by cobalt required MD-2 and was abolished by human TLR4 mutations of histidine residues at positions 456 and 458. We demonstrated that activation of TLR4 by nickel and cobalt ions can trigger both the MyD88-dependent and the -independent pathway. Based on our results we propose that predominantly hydrophobic interactions between MD-2 and TLR4 contribute to the stabilization of the TLR4/MD-2/metal ion complex in a conformation that enables activation.
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Affiliation(s)
- Alja Oblak
- Department of Biotechnology, National institute of Chemistry, Ljubljana, Slovenia
- Centre of Excellence EN-FIST, Ljubljana, Slovenia
| | - Jelka Pohar
- Department of Biotechnology, National institute of Chemistry, Ljubljana, Slovenia
- Centre of Excellence EN-FIST, Ljubljana, Slovenia
| | - Roman Jerala
- Department of Biotechnology, National institute of Chemistry, Ljubljana, Slovenia
- Centre of Excellence EN-FIST, Ljubljana, Slovenia
- * E-mail:
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Species-specific activation of TLR4 by hypoacylated endotoxins governed by residues 82 and 122 of MD-2. PLoS One 2014; 9:e107520. [PMID: 25203747 PMCID: PMC4159346 DOI: 10.1371/journal.pone.0107520] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 08/19/2014] [Indexed: 11/20/2022] Open
Abstract
The Toll-like receptor 4/MD-2 receptor complex recognizes endotoxin, a Gram-negative bacterial cell envelope component. Recognition of the most potent hexaacylated form of endotoxin is mediated by the sixth acyl chain that protrudes from the MD-2 hydrophobic pocket and bridges TLR4/MD-2 to the neighboring TLR4 ectodomain, driving receptor dimerization via hydrophobic interactions. In hypoacylated endotoxins all acyl chains could be accommodated within the binding pocket of the human hMD-2. Nevertheless, tetra- and pentaacylated endotoxins activate the TLR4/MD-2 receptor of several species. We observed that amino acid residues 82 and 122, located at the entrance to the endotoxin binding site of MD-2, have major influence on the species-specific endotoxin recognition. We show that substitution of hMD-2 residue V82 with an amino acid residue with a bulkier hydrophobic side chain enables activation of TLR4/MD-2 by pentaacylated and tetraacylated endotoxins. Interaction of the lipid A phosphate group with the amino acid residue 122 of MD-2 facilitates the appropriate positioning of the hypoacylated endotoxin. Moreover, mouse TLR4 contributes to the agonistic effect of pentaacylated msbB endotoxin. We propose a molecular model that explains how the molecular differences between the murine or equine MD-2, which both have sufficiently large hydrophobic pockets to accommodate all five or four acyl chains, influence the positioning of endotoxin so that one of the acyl chains remains outside the pocket and enables hydrophobic interactions with TLR4, leading to receptor activation.
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