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Hsiao PY, Huang RY, Huang LW, Chu CL, Dyke TV, Mau LP, Cheng CD, Sung CE, Weng PW, Wu YC, Shieh YS, Cheng WC. MyD88 exacerbates inflammation-induced bone loss by modulating dynamic equilibrium between Th17/Treg cells and subgingival microbiota dysbiosis. J Periodontol 2024; 95:764-777. [PMID: 38523602 DOI: 10.1002/jper.23-0561] [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: 10/08/2023] [Revised: 02/16/2024] [Accepted: 02/23/2024] [Indexed: 03/26/2024]
Abstract
BACKGROUND This study aimed to investigate the contribution of myeloid differentiation primary-response gene 88 (MyD88) on the differentiation of T helper type 17 (Th17) and regulatory T (Treg) cells and the emerging subgingival microbiota dysbiosis in Porphyromonas gingivalis-induced experimental periodontitis. METHODS Alveolar bone loss, infiltrated inflammatory cells, immunostained cells for tartrate-resistant acid phosphatase (TRAP), the receptor activator of nuclear factor-kB ligand (RANKL), and osteoprotegerin (OPG) were quantified by microcomputerized tomography and histological staining between age- and sex-matched homozygous littermates (wild-type [WT, Myd88+/+] and Myd88-/- on C57BL/6 background). The frequencies of Th17 and Treg cells in cervical lymph nodes (CLNs) and spleen were determined by flow cytometry. Cytokine expression in gingival tissues, CLNs, and spleens were studied by quantitative polymerase chain reaction (qPCR). Analysis of the composition of the subgingival microbiome and functional annotation of prokaryotic taxa (FAPROTAX) analysis were performed. RESULTS P. gingivalis-infected Myd88-/- mice showed alleviated bone loss, TRAP+ osteoclasts, and RANKL/OPG ratio compared to WT mice. A significantly higher percentage of Foxp3+CD4+ T cells in infected Myd88-/- CLNs and a higher frequency of RORγt+CD4+ T cells in infected WT mice was noted. Increased IL-10 and IL-17a expressions in gingival tissue at D14-D28 then declined in WT mice, whereas an opposite pattern was observed in Myd88-/- mice. The Myd88-/- mice exhibited characteristic increases in gram-positive species and species having probiotic properties, while gram-negative, anaerobic species were noted in WT mice. FAPROTAX analysis revealed increased aerobic chemoheterotrophy in Myd88-/- mice, whereas anaerobic chemoheterotrophy was noted in WT mice after P. gingivalis infection. CONCLUSIONS MyD88 plays an important role in inflammation-induced bone loss by modulating the dynamic equilibrium between Th17/Treg cells and dysbiosis in P. gingivalis-induced experimental periodontitis.
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Affiliation(s)
- Po-Yan Hsiao
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Ren-Yeong Huang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Department of Periodontology, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
- Graduate Institute of Dental Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Lin-Wei Huang
- Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Ching-Liang Chu
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Thomas Van Dyke
- Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts, USA
- Department of Applied Oral Sciences, The Forsyth Institute, Cambridge, Massachusetts, USA
| | - Lian-Ping Mau
- Department of Periodontics, Chi Mei Medical Center, Tainan, Taiwan
| | - Chia-Dan Cheng
- Department of Periodontology, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
- Graduate Institute of Dental Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Cheng-En Sung
- Department of Periodontology, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
- Graduate Institute of Dental Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Pei-Wei Weng
- Department of Orthopaedics, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yu-Chiao Wu
- Graduate Institute of Dental Sciences, National Defense Medical Center, Taipei, Taiwan
- Department of Operative Dentistry and Endodontics, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
| | - Yi-Shing Shieh
- Graduate Institute of Dental Sciences, National Defense Medical Center, Taipei, Taiwan
- Department of Operative Dentistry and Endodontics, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
| | - Wan-Chien Cheng
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Department of Periodontology, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
- Graduate Institute of Dental Sciences, National Defense Medical Center, Taipei, Taiwan
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Li Z, Zhao M, Yang Y, Zou Z, Zhang L, Jiang F, Du D, Zhou P. Treatment of a MyD88 inhibitor alleviates rejection and inflammation in xenotransplantation by inhibiting dendritic cells activation and trained immunity in macrophages. Int Immunopharmacol 2024; 130:111664. [PMID: 38377850 DOI: 10.1016/j.intimp.2024.111664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 01/30/2024] [Accepted: 02/05/2024] [Indexed: 02/22/2024]
Abstract
BACKGROUND Acute vascular rejection (AVR) and systemic inflammation in xenograft recipients (SIXR) negatively impact the xenografts survival, and novel immunosuppressants are required to improve survival outcomes. We previously reported that TJ-M2010-5, a myeloid differentiation factor 88 (MyD88) inhibitor, exerts excellent anti-rejection effects in allogeneic transplantation. The aim of the present study was to evaluate the efficacy of TJ-M2010-5 in preventing AVR and SIXR and to investigate whether combined treatment of TJ-M2010-5 with anti-CD154 antibody (MR1) could prolong xenograft survival furthermore. METHODS A model involving heart transplantation from Sprague-Dawley rats to BALB/c mice was established in vivo, and the xenografts developed typical AVR. Bone marrow-derived dendritic cells and macrophages were cultured to study the underlying mechanisms induced by rat cardiomyocyte lysate stimulation in vitro. RESULTS TJ-M2010-5 monotherapy prolonged xenograft survival, although combination treatment with MR1 further enhanced the anti-AVR and anti-SIXR effects with about 21 days graft survival, compared to monotherapy. TJ-M2010-5 reduced dendritic cell and macrophage activation induced by xenotransplantation, downregulated CD80/CD86 expression, suppressed B-cell activation and anti-donor antibody generation, reduced pro-inflammatory cytokine production and tissue factor expression, and attenuated epigenetic modifications underlying interleukin-6 and tumor necrosis factor-α production in macrophages by inhibiting nuclear factor kappa B nuclear translocation. CONCLUSIONS TJ-M2010-5 attenuated AVR and SIXR and contributed to xenograft survival by inhibiting dendritic cell and macrophage activation. A dual-system inhibition strategy combining TJ-M2010-5 with anti-CD154 antibody achieved better results in xenotransplantation.
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Affiliation(s)
- Zeyang Li
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Minghui Zhao
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yang Yang
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zhimiao Zou
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Limin Zhang
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Fengchao Jiang
- Academy of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Dunfeng Du
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Key Laboratory of Organ Transplantation, Ministry of Education, NHC Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, China.
| | - Ping Zhou
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Key Laboratory of Organ Transplantation, Ministry of Education, NHC Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, China.
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Zheng K, Lv B, Wu L, Wang C, Xu H, Li X, Wu Z, Zhao Y, Zheng Z. Protecting effect of emodin in experimental autoimmune encephalomyelitis mice by inhibiting microglia activation and inflammation via Myd88/PI3K/Akt/NF-κB signalling pathway. Bioengineered 2022; 13:9322-9344. [PMID: 35287559 PMCID: PMC9161934 DOI: 10.1080/21655979.2022.2052671] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Experimental autoimmune encephalomyelitis (EAE) is characterised by demyelination of the central nervous system. Emodin is an anthraquinone derivative with comprehensive anti-inflammatory, anti-cancer, and immunomodulatory effects and is widely used in the treatment of inflammatory, tumour, and immune system diseases. However, none of the clinical or experimental studies have explored the therapeutic efficacy of emodin in EAE/multiple sclerosis (MS). Thus, we evaluated the protective effect of emodin on EAE mediated via inhibition of microglia activation and inflammation. Wild-type mice were randomly divided into the normal control, EAE, low-dose emodin, and high-dose emodin groups. Clinical scores and pathological changes were assessed 21 days after immunisation. The network pharmacology approach was used to elucidate underlying mechanisms by using an online database. Molecular docking, polymerase chain reaction tests, western blotting, and immunofluorescence were performed to verify the network pharmacology results. An in vivo experiment showed that high-dose emodin ameliorated clinical symptoms, inflammatory cell infiltration, and myelination. Pharmacological network analysis showed AKT1 was the main target and that emodin played a key role in MS treatment mainly via the PI3K-Akt pathway. Molecular docking showed that emodin bound well with PI3K, AKT1, and NFKB1. Emodin decreased the expression of phosphorylated(p)-PI3K, p-Akt, NF-κB, and myeloid differentiation factor 88 and the levels of markers (CD86 and CD206) in M1- and M2-phenotype microglia in EAE. Thus, emodin inhibited microglial activation and exhibited anti-inflammatory and neuroprotective effects against EAE via the Myd88/PI3K/Akt/NF-κB signalling pathway. In conclusion, emodin has a promising role in EAE/MS treatment, warranting further detailed studies.
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Affiliation(s)
- Kenan Zheng
- The First Clinical School, Guangzhou University of Chinese Medicine, Guangzhou, China.,Lingnan Medical Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Baojiang Lv
- The First Clinical School, Guangzhou University of Chinese Medicine, Guangzhou, China.,Lingnan Medical Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lulu Wu
- The First Clinical School, Guangzhou University of Chinese Medicine, Guangzhou, China.,Lingnan Medical Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Chen Wang
- Department of Traditional Chinese Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Haoyou Xu
- Department of Neurology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, China
| | - Xiaojun Li
- The Second Clinical School, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhibing Wu
- Department of Neurology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yuanqi Zhao
- Department of Neurology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, China
| | - Zequan Zheng
- Department of Neurology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, China.,Doctoral candidates with the same academic level of Guangzhou University of Chinese Medicine, Guangzhou, China
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Marks KE, Cho K, Stickling C, Reynolds JM. Toll-like Receptor 2 in Autoimmune Inflammation. Immune Netw 2021; 21:e18. [PMID: 34277108 PMCID: PMC8263214 DOI: 10.4110/in.2021.21.e18] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 06/22/2021] [Indexed: 12/11/2022] Open
Abstract
TLR signaling is critical for broad scale immune recognition of pathogens and/or danger molecules. TLRs are particularly important for the activation and the maturation of cells comprising the innate immune response. In recent years it has become apparent that several different TLRs regulate the function of lymphocytes as well, albeit to a lesser degree compared to innate immunity. TLR2 heterodimerizes with either TLR1 or TLR6 to broadly recognize bacterial lipopeptides as well as several danger-associated molecular patterns. In general, TLR2 signaling promotes immune cell activation leading to tissue inflammation, which is advantageous for combating an infection. Conversely, inappropriate or dysfunctional TLR2 signaling leading to an overactive inflammatory response could be detrimental during sterile inflammation and autoimmune disease. This review will highlight and discuss recent research advances linking TLR2 engagement to autoimmune inflammation.
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Affiliation(s)
- Kathryne E Marks
- Center for Cancer Cell Biology, Immunology, and Infection, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Kaylin Cho
- Center for Cancer Cell Biology, Immunology, and Infection, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Courtney Stickling
- Center for Cancer Cell Biology, Immunology, and Infection, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
| | - Joseph M Reynolds
- Center for Cancer Cell Biology, Immunology, and Infection, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
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Even-Or O, Avniel-Polak S, Barenholz Y, Nussbaum G. The cationic liposome CCS/C adjuvant induces immunity to influenza independently of the adaptor protein MyD88. Hum Vaccin Immunother 2020; 16:3146-3154. [PMID: 32401698 PMCID: PMC8641586 DOI: 10.1080/21645515.2020.1750247] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 03/18/2020] [Accepted: 03/26/2020] [Indexed: 02/07/2023] Open
Abstract
Traditional non-living vaccines are often least effective in the populations that need them most, such as neonates and elderly adults. Vaccine adjuvants are one approach to boost the immunogenicity of antigens in populations with reduced immunity. Ideally, vaccine adjuvants will increase the seroconversion rates across the population, lead to stronger immune responses, and enable the administration of fewer vaccine doses. We previously demonstrated that a cationic liposomal formulation of the commercial influenza split virus vaccine (CCS/C-HA) enhanced cellular and humoral immunity to the virus, increased seroconversion rates, and improved survival after live virus challenge in a preclinical model, as compared to the commercial vaccine as is (F-HA). We now evaluated vaccine efficacy in different strains and sexes of mice and determined the role of innate immunity in the mechanism of action of the CCS/C adjuvant by testing the response of mice deficient in Toll-like receptors or the TLR/IL-1 adaptor protein MyD88 following immunization with CCS/C-HA vs. F-HA. Although TLR2- and TLR4-deficient mice responded to F-HA immunization, F-HA immunization failed to engender a significant immune response in the absence of MyD88. In contrast, immunization with the CCS/C-HA vaccine overcame the requirement for MyD88 in the response to the commercial vaccine and improved the immune responses and seroconversion rates in all strains of mice tested, including those deficient in TLR2 and TLR4.
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Affiliation(s)
- Orli Even-Or
- Laboratory of Membrane and Liposome Research, Department of Biochemistry, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Shani Avniel-Polak
- Institute of Dental Sciences, The Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel
| | - Yechezkel Barenholz
- Laboratory of Membrane and Liposome Research, Department of Biochemistry, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Gabriel Nussbaum
- Institute of Dental Sciences, The Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel
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Noorbakhsh SM, Razavi A, Moghadam NB, Saadat P, Hoseini M, Aghazadeh Z, Mobini M, Oraei M, Mirshafiey A. Effects of guluronic acid (G2013) on gene expression of TLR2, TLR4, MyD88, TNF-α and CD52 in multiple sclerosis under in vitro conditions. Immunopharmacol Immunotoxicol 2019; 41:586-590. [DOI: 10.1080/08923973.2019.1672179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | - Alireza Razavi
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Nahid Beladi Moghadam
- Department of Neurology, Shahid Beheshti Universiry of Medical Science, Tehran, Iran
| | - Payam Saadat
- Mobility Impairment Research Center, Health Research Institue, Babol University of Medical Sciences, Babol, Iran
| | - Mostafa Hoseini
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Zahra Aghazadeh
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Mobini
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mona Oraei
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Abbas Mirshafiey
- Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
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Liu X, Deng J, Li R, Tan C, Li H, Yang Z, Chen L, Chen Y, Tan X. ERβ-selective agonist alleviates inflammation in a multiple sclerosis model via regulation of MHC II in microglia. Am J Transl Res 2019; 11:4411-4424. [PMID: 31396345 PMCID: PMC6684890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 06/13/2019] [Indexed: 06/10/2023]
Abstract
Multiple sclerosis (MS) is an autoimmune, demyelinating, and neurodegenerative disease of the central nervous system (CNS) that affects 2-2.5 million people worldwide. Although the etiology of MS is not well known, MS is widely considered to be an autoimmune disease. Currently approved MS drugs reduce relapse rates but fail to reverse or prevent neurodegeneration and disability progression. Increasing evidence indicates that microglia and major histocompatibility complex class II (MHC II) expression in these cells play important roles in the pathophysiology of MS. For a T cell to contribute to CNS pathogenesis, it must be reactivated by antigen-presenting cells within the CNS parenchyma. Susceptibility to MS is associated with MHC II genes, suggesting that presentation of antigens on MHC II plays an important role in CD4+ T-cell reactivation and disease initiation. An ERβ-selective agonist was previously reported to suppress reactivation of T cells invading the spinal cord, thereby reducing the severity of symptoms and decreasing mortality in the first 2 weeks after disease onset. However, the mechanism by which the expression of MHC II in microglia is regulated by ERβ-selective agonists is still unclear. Therefore, we hypothesize that ERβ-selective agonists inhibit MHC II expression in microglia via inhibition of class II trans-activator (CIITA) expression by a mechanism involving inhibition of the translocation of IFNγ regulatory factor (IRF-1) to the nucleus, thereby inhibiting the inflammatory response and symptoms in the MS model.
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Affiliation(s)
- Xi Liu
- Department of Neurology, Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010, China
| | - Jing Deng
- Department of Neurology, Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010, China
| | - Rong Li
- Department of Neurology, Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010, China
| | - Changhong Tan
- Department of Neurology, Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010, China
| | - Hongli Li
- Department of Histology and Embryology, Third Military Medical UniversityChongqing 400038, China
| | - Zhong Yang
- Department of Clinical Hematology, Southwest Hospital, Third Military Medical University (Army Medical University)Chongqing 400038, China
| | - Lifen Chen
- Department of Neurology, Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010, China
| | - Yangmei Chen
- Department of Neurology, Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010, China
| | - Xinjie Tan
- Department of Neurology, Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010, China
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Dishon S, Schumacher-Klinger A, Gilon C, Hoffman A, Nussbaum G. Myristoylation Confers Oral Bioavailability and Improves the Bioactivity of c(MyD 4-4), a Cyclic Peptide Inhibitor of MyD88. Mol Pharm 2019; 16:1516-1522. [PMID: 30860380 DOI: 10.1021/acs.molpharmaceut.8b01180] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Myeloid differentiation primary response 88 (MyD88) is an intracellular adaptor protein central to the signaling of multiple receptors involved in inflammation. Since innate immune inflammation promotes autoimmunity, MyD88 is an attractive target in autoimmune disease. We previously developed c(MyD 4-4), a novel cyclic peptide competitive inhibitor of MyD88 dimerization that is metabolically stable. Parenteral administration of c(MyD 4-4) reduces disease severity in a mouse model of the human autoimmune disease multiple sclerosis. We now show that N-terminal myristoylation of c(MyD 4-4) enhances the competitive inhibition of MyD88 dimerization in living cells, leading to improved inhibition of the Toll-like receptor and IL-1 receptor signaling. Importantly, myristoylation converts c(MyD 4-4) to an orally bioavailable inhibitor of MyD88. Oral administration of c(MyD 4-4) significantly lowered the inflammatory cytokines secreted by peripheral autoimmune T cells in mice immunized with myelin antigens and ameliorated disease severity in the mouse model of multiple sclerosis. Taken together, we show the conversion of a protein active region to a metabolically stable, selective cyclic peptide that is orally bioavailable.
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Affiliation(s)
- Shira Dishon
- The Institute of Dental Sciences , Hebrew University-Hadassah Faculty of Dental Medicine , Jerusalem 91120 , Israel
| | - Adi Schumacher-Klinger
- The Institute for Drug Research , Hebrew University-Hadassah Faculty of Medicine , Jerusalem 91120 , Israel
| | - Chaim Gilon
- The Institute of Chemistry , Hebrew University , Jerusalem 91120 , Israel
| | - Amnon Hoffman
- The Institute for Drug Research , Hebrew University-Hadassah Faculty of Medicine , Jerusalem 91120 , Israel
| | - Gabriel Nussbaum
- The Institute of Dental Sciences , Hebrew University-Hadassah Faculty of Dental Medicine , Jerusalem 91120 , Israel
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Development of a Novel Backbone Cyclic Peptide Inhibitor of the Innate Immune TLR/IL1R Signaling Protein MyD88. Sci Rep 2018; 8:9476. [PMID: 29930295 PMCID: PMC6013495 DOI: 10.1038/s41598-018-27773-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/04/2018] [Indexed: 12/28/2022] Open
Abstract
MyD88 is a cytoplasmic adaptor protein that plays a central role in signaling downstream of the TLRs and the IL1R superfamily. We previously demonstrated that MyD88 plays a critical role in EAE, the murine model of multiple sclerosis, and showed that the MyD88 BB-loop decoy peptide RDVLPGT ameliorates EAE. We now designed and screened a library of backbone cyclized peptides based on the linear BB loop peptide, to identify a metabolically stable inhibitor of MyD88 that retains the binding properties of the linear peptide. We identified a novel cyclic peptide protein mimetic that inhibits inflammatory responses to TLR ligands, and NFκB activation in response to IL-1 activation. The inhibitor, c(MyD 4-4), is metabolically stable in comparison to the linear peptide, blocks MyD88 in a specific manner, and inhibits MyD88 function by preventing MyD88 dimerization. Finally, treatment of mice with c(MyD 4-4) reduced the severity of clinical disease in the murine EAE model of multiple sclerosis. Thus, modulation of MyD88-dependent signaling using c(MyD 4-4) is a potential therapeutic strategy to lower innate immune inflammation in autoimmune CNS disease.
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