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Tsuji G, Yamamura K, Kawamura K, Kido-Nakahara M, Ito T, Nakahara T. Novel Therapeutic Targets for the Treatment of Atopic Dermatitis. Biomedicines 2023; 11:biomedicines11051303. [PMID: 37238974 DOI: 10.3390/biomedicines11051303] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/20/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
Atopic dermatitis (AD) is a chronic inflammatory skin disease that significantly impacts quality of life. The pathogenesis of AD is a complex combination of skin barrier dysfunction, type II immune response, and pruritus. Progress in the understanding of the immunological mechanisms of AD has led to the recognition of multiple novel therapeutic targets. For systemic therapy, new biologic agents that target IL-13, IL-22, IL-33, the IL-23/IL-17 axis, and OX40-OX40L are being developed. Binding of type II cytokines to their receptors activates Janus kinase (JAK) and its downstream signal, namely signal transduction and activator of transcription (STAT). JAK inhibitors block the activation of the JAK-STAT pathway, thereby blocking the signaling pathways mediated by type II cytokines. In addition to oral JAK inhibitors, histamine H4 receptor antagonists are under investigation as small-molecule compounds. For topical therapy, JAK inhibitors, aryl hydrocarbon receptor modulators, and phosphodiesterase-4 inhibitors are being approved. Microbiome modulation is also being examined for the treatment of AD. This review outlines current and future directions for novel therapies of AD that are currently being investigated in clinical trials, focusing on their mechanisms of action and efficacy. This supports the accumulation of data on advanced treatments for AD in the new era of precision medicine.
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Affiliation(s)
- Gaku Tsuji
- Research and Clinical Center for Yusho and Dioxin, Kyushu University Hospital, Fukuoka 812-8582, Japan
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Kazuhiko Yamamura
- Research and Clinical Center for Yusho and Dioxin, Kyushu University Hospital, Fukuoka 812-8582, Japan
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Koji Kawamura
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Makiko Kido-Nakahara
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Takamichi Ito
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Takeshi Nakahara
- Research and Clinical Center for Yusho and Dioxin, Kyushu University Hospital, Fukuoka 812-8582, Japan
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
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Thangam EB, Jemima EA, Singh H, Baig MS, Khan M, Mathias CB, Church MK, Saluja R. The Role of Histamine and Histamine Receptors in Mast Cell-Mediated Allergy and Inflammation: The Hunt for New Therapeutic Targets. Front Immunol 2018; 9:1873. [PMID: 30150993 PMCID: PMC6099187 DOI: 10.3389/fimmu.2018.01873] [Citation(s) in RCA: 234] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 07/30/2018] [Indexed: 11/22/2022] Open
Abstract
Histamine and its receptors (H1R–H4R) play a crucial and significant role in the development of various allergic diseases. Mast cells are multifunctional bone marrow-derived tissue-dwelling cells that are the major producer of histamine in the body. H1R are expressed in many cells, including mast cells, and are involved in Type 1 hypersensitivity reactions. H2R are involved in Th1 lymphocyte cytokine production. H3R are mainly involved in blood–brain barrier function. H4R are highly expressed on mast cells where their stimulation exacerbates histamine and cytokine generation. Both H1R and H4R have important roles in the progression and modulation of histamine-mediated allergic diseases. Antihistamines that target H1R alone are not entirely effective in the treatment of acute pruritus, atopic dermatitis, allergic asthma, and other allergic diseases. However, antagonists that target H4R have shown promising effects in preclinical and clinical studies in the treatment of several allergic diseases. In the present review, we examine the accumulating evidence suggesting novel therapeutic approaches that explore both H1R and H4R as therapeutic targets for histamine-mediated allergic diseases.
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Affiliation(s)
- Elden Berla Thangam
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Ebenezer Angel Jemima
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Himadri Singh
- Department of Biochemistry, All India Institute of Medical Sciences, Bhopal, Madhya Pradesh, India
| | - Mirza Saqib Baig
- Discipline of Biosciences and Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, Madhya Pradesh, India
| | - Mahejibin Khan
- Central Food Technological Research Institute-Resource Centre, Lucknow, India
| | - Clinton B Mathias
- Department of Pharmaceutical and Administrative Sciences, Western New England University, Springfield, MA, United States
| | - Martin K Church
- Department of Dermatology and Allergy, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Rohit Saluja
- Department of Biochemistry, All India Institute of Medical Sciences, Bhopal, Madhya Pradesh, India.,Department of Biotechnology, Government of India, New Delhi, India
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Salem A, Almahmoudi R, Listyarifah D, Siponen M, Maaninka K, Al-Samadi A, Salo T, Eklund KK. Histamine H 4 receptor signalling in tongue cancer and its potential role in oral carcinogenesis - a short report. Cell Oncol (Dordr) 2017; 40:621-630. [PMID: 28653289 DOI: 10.1007/s13402-017-0336-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2017] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Recent reports indicate that histamine and its novel, high-affinity histamine H4 receptor (H4R) play a role in carcinogenesis, and thus H4R signalling has become a focus of increasing interest in the pathogenesis of many cancers. The roles of H4R in oral epithelial dysplasia (OED) and oral tongue squamous cell carcinoma (OTSCC) are unknown. The purpose of this study was to assess H4R expression in OTSCC patients and in OTSCC-derived cell lines. METHODS Biopsies taken from OED, OTSCC and healthy oral mucosa were studied by immunostaining. Primary human oral keratinocytes (HOKs) and two OTSCC-derived cell lines (HSC-3 and SCC-25) were used for the in vitro studies. Quantitative real-time PCR was used to measure oncogene expression in the stimulated HOKs. RESULTS We found that H4R-immunoreactivity was significantly reduced in the OED and OTSCC samples, especially in the samples with higher histopathological grades and noticeably increased mast cell counts. The presence of H4R in HSC-3 cells had clearly waned, in contrast to the HOKs. Gene expression data indicated that histamine-relevant inflammatory and environmental elements may participate in the regulation of oncogenes. CONCLUSIONS Our results suggest an association between H4R and oral carcinogenesis. Furthermore, our findings raise a potential implication of histamine-mediated factors in the regulation of oncogenes, possibly via mast cells, as crucial components of the tumor microenvironment. The identification of new elements that govern oral cancer development is highly relevant for the development of novel therapeutic approaches in OTSCC.
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Affiliation(s)
- Abdelhakim Salem
- Department of Clinical Medicine, Clinicum, University of Helsinki, Helsinki, Finland. .,Department of Oral and Maxillofacial Diseases, Clinicum, University of Helsinki, Haartmaninkatu 8, Biomedicum Helsinki 1, PO Box 63, FI-00029 HUS, Helsinki, Finland.
| | - Rabeia Almahmoudi
- Department of Oral and Maxillofacial Diseases, Clinicum, University of Helsinki, Haartmaninkatu 8, Biomedicum Helsinki 1, PO Box 63, FI-00029 HUS, Helsinki, Finland
| | - Dyah Listyarifah
- Department of Clinical Medicine, Clinicum, University of Helsinki, Helsinki, Finland.,Department of Oral and Maxillofacial Diseases, Clinicum, University of Helsinki, Haartmaninkatu 8, Biomedicum Helsinki 1, PO Box 63, FI-00029 HUS, Helsinki, Finland.,Department of Dental Biomedical Sciences, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Maria Siponen
- Department of Oral and Maxillofacial Diseases, Kuopio University Hospital, Kuopio, Finland.,Institute of Dentistry, Faculty of Health Sciences, University of Eastern Finland, Joensuu, Finland
| | | | - Ahmed Al-Samadi
- Department of Oral and Maxillofacial Diseases, Clinicum, University of Helsinki, Haartmaninkatu 8, Biomedicum Helsinki 1, PO Box 63, FI-00029 HUS, Helsinki, Finland
| | - Tuula Salo
- Department of Oral and Maxillofacial Diseases, Clinicum, University of Helsinki, Haartmaninkatu 8, Biomedicum Helsinki 1, PO Box 63, FI-00029 HUS, Helsinki, Finland.,Cancer and Translational Medicine Research Unit, University of Oulu, Oulu, Finland.,Medical Research Center, Oulu University Hospital, Oulu, Finland
| | - Kari K Eklund
- Department of Clinical Medicine, Clinicum, University of Helsinki, Helsinki, Finland.,Department of Rheumatology, Helsinki University and Helsinki University Hospital, Helsinki, Finland
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Han SH, Hur MS, Kim MJ, Kim BM, Kim KW, Kim HR, Choe YB, Ahn KJ, Lee YW. Preliminary study of histamine H 4 receptor expressed on human CD4 + T cells and its immunomodulatory potency in the IL-17 pathway of psoriasis. J Dermatol Sci 2017; 88:29-35. [PMID: 28592369 DOI: 10.1016/j.jdermsci.2017.05.011] [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: 02/25/2017] [Revised: 04/26/2017] [Accepted: 05/18/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND Previous studies have shown the expression of histamine H4 receptor (H4R) on CD4+ T cells, especially human CD4+ Th2-polarized T cells. OBJECTIVE This study aimed to investigate the role of H4R on these effector T cells in psoriasis. METHODS We enrolled three patients each with active psoriasis, inactive psoriasis, scalp seborrheic dermatitis, and three normal controls, and compared the basal expression of H4R mRNA in their peripheral blood CD4+ T cells. Then, we identified H4R expression in dermal CD4+ T cells. Furthermore, we investigated H4R expression after stimulating separated peripheral blood CD4+ T cells with several inflammatory cytokines. RESULTS The results showed higher H4R expression in the active psoriasis group compared to the inactive psoriasis group. It was interesting that interleukin (IL)-23, which is a representative cytokine contributing to Th17 cell differentiation, stimulated H4R expression significantly. After adding a selective H4R antagonist (JNJ-7777120) while the CD4+ T cells were polarized into Th17 cells, we observed a tendency toward suppressed IL-17 secretion. CONCLUSIONS Histamine stimulation influences the IL-17 pathway in psoriasis via the fourth histamine receptor subtype, H4R, on CD4+ T cells. The immunomodulatory roles of H4R suggest its potency as a new therapeutic target for obstinate psoriasis.
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Affiliation(s)
- Song Hee Han
- Department of Dermatology, Konkuk University School of Medicine, Seoul, Republic of Korea
| | - Min Seok Hur
- Department of Dermatology, Konkuk University School of Medicine, Seoul, Republic of Korea
| | - Min Jung Kim
- Department of Dermatology, Konkuk University School of Medicine, Seoul, Republic of Korea
| | - Bo Mi Kim
- Convergent Research Consortium for Immunologic Disease, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Kyoung Woon Kim
- Convergent Research Consortium for Immunologic Disease, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Hae Rim Kim
- Division of Rheumatology, Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Republic of Korea
| | - Yong Beom Choe
- Department of Dermatology, Konkuk University School of Medicine, Seoul, Republic of Korea; Research Institute of Medical Science, Konkuk University, Seoul, Republic of Korea
| | - Kyu Joong Ahn
- Department of Dermatology, Konkuk University School of Medicine, Seoul, Republic of Korea; Research Institute of Medical Science, Konkuk University, Seoul, Republic of Korea
| | - Yang Won Lee
- Department of Dermatology, Konkuk University School of Medicine, Seoul, Republic of Korea; Research Institute of Medical Science, Konkuk University, Seoul, Republic of Korea.
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Kim KW, Kim BM, Lee KA, Lee SH, Firestein GS, Kim HR. Histamine and Histamine H4 Receptor Promotes Osteoclastogenesis in Rheumatoid Arthritis. Sci Rep 2017; 7:1197. [PMID: 28446753 PMCID: PMC5430934 DOI: 10.1038/s41598-017-01101-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/22/2017] [Indexed: 01/08/2023] Open
Abstract
Histamine H4 receptor (H4R) has immune-modulatory and chemotaxic effects in various immune cells. This study aimed to determine the osteoclastogenic role of H4R in rheumatoid arthritis (RA). The concentration of histamine in synovial fluid (SF) and sera in patients with RA was measured using ELISA. After RA SF and peripheral blood (PB) CD14+ monocytes were treated with histamine, IL-17, IL-21 and IL-22, and a H4R antagonist (JNJ7777120), the gene expression H4R and RANKL was determined by real-time PCR. Osteoclastogenesis was assessed by counting TRAP–positive multinucleated cells in PB CD14+ monocytes cultured with histamine, Th17 cytokines and JNJ7777120. SF and serum concentration of histamine was higher in RA, compared with osteoarthritis and healthy controls. The expression of H4R was increased in PB monocytes in RA patients. Histamine, IL-6, IL-17, IL-21 and IL-22 induced the expression of H4R in monocytes. Histamine, IL-17, and IL-22 stimulated RANKL expression in RA monocytes and JNJ7777120 reduced the RANKL expression. Histamine and Th17 cytokines induced the osteoclast differentiation from monocytes and JNJ7777120 decreased the osteoclastogenesis. H4R mediates RANKL expression and osteoclast differentiation induced by histamine and Th17 cytokines. The blockage of H4R could be a new therapeutic modality for prevention of bone destruction in RA.
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Affiliation(s)
- Kyoung-Woon Kim
- Convergent Research Consortium in Immunologic Disease, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Bo-Mi Kim
- Convergent Research Consortium in Immunologic Disease, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Kyung-Ann Lee
- Department of Rheumatology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea
| | - Sang-Heon Lee
- Department of Rheumatology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea
| | - Gary S Firestein
- Division of Rheumatology, Allergy and Immunology, University of California San Diego, La Jolla, California, United States of America
| | - Hae-Rim Kim
- Department of Rheumatology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea.
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Ueno K. [Expression and function of the histamine receptors in dermal and articular tissues]. YAKUGAKU ZASSHI 2015; 134:1093-108. [PMID: 25366908 DOI: 10.1248/yakushi.14-00183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Histamine was first identified in 1910 as a physiologically active amine. It is now recognized for its multiple regulatory activities in the digestive, neuronal, and immune systems, and new roles are still being elucidated. Histamine exerts its effects through four distinct receptor subtypes. The histamine H4 receptor was identified in 2000 and is the most recently identified of the four histamine receptors. It is expressed primarily in immune cells and is involved in physiologic functions related to inflammation and allergy. Recently, the H4 receptor was highlighted as a promising therapeutic target in atopic dermatitis, asthma, and chronic arthritis. In fact, some H4 receptor antagonists have reached clinical trials for the treatment of asthma, atopic dermatitis, and allergic rhinitis. Based on an initial assessment of its distribution, the H4 receptor has been referred to as the histamine receptor of the hematopoietic system. However, the H4 receptor has also been implicated in the regulation of other non-hematopoietic systems. Here, I review the expression and function of the identified histamine receptors, including the H4 receptor with a focus on articular and dermal tissues. In articular tissue, H4 receptor expression has been detected in synovial cells. Chondrocytes, a major cell source for cartilage tissue engineering, also express the H4 receptor. In skin, the H4 receptor is expressed in both the epidermis and dermis, with stronger receptor expression in the epidermis. Further understanding of the functions of H4 receptors in non-hematopoietic cells might lead to novel treatments for diseases with unmet medical needs.
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Affiliation(s)
- Koichi Ueno
- Department of Geriatric Pharmacology and Therapeutics, Graduate School of Pharmaceutical Sciences, Chiba University
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Ohsawa Y, Hirasawa N. The role of histamine H1 and H4 receptors in atopic dermatitis: from basic research to clinical study. Allergol Int 2014; 63:533-42. [PMID: 25249063 DOI: 10.2332/allergolint.13-ra-0675] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 06/05/2014] [Indexed: 12/21/2022] Open
Abstract
Histamine plays important roles in inflammation and nervous irritability in allergic disorders, including atopic dermatitis (AD). It has been shown to regulate the expression of pruritic factors, such as nerve growth factor and semaphorin 3A, in skin keratinocytes via histamine H1 receptor (H1R). Furthermore, H1R antagonist reduced the level of IL-31, a cytokine involving the skin barrier and pruritus, in chronic dermatitis lesions in NC/Nga mice and patients with AD. Histamine plays roles in the induction of allergic inflammation by activating eosinophils, mast cells, basophils, and Th2 cells via histamine H4 receptor (H4R). H4R, in addition to H1R, is expressed on sensory neurons, and a decrease in scratching behaviors was observed in H4R-deficient mice and mice treated with a H4R antagonist. We found that the combined administration of H1R and H4R antagonists inhibited the itch response and chronic allergic inflammation, and had a pharmacological effect similar to that of prednisolone. Although the oral administration of H1R antagonists is widely used to treat AD, it is not very effective. In contrast, JNJ39758979, a novel H4R antagonist, had marked effects against pruritus in Japanese patients with AD in a phase II clinical trial. Next generation antihistaminic agents possessing H1R and H4R antagonistic actions may be a potent therapeutic drug for AD.
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MESH Headings
- Animals
- Clinical Trials as Topic
- Dermatitis, Atopic/drug therapy
- Dermatitis, Atopic/genetics
- Dermatitis, Atopic/metabolism
- Disease Models, Animal
- Drug Therapy, Combination
- Histamine Antagonists/administration & dosage
- Histamine Antagonists/therapeutic use
- Histamine H1 Antagonists/administration & dosage
- Histamine H1 Antagonists/therapeutic use
- Humans
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Histamine/genetics
- Receptors, Histamine/metabolism
- Receptors, Histamine H1/genetics
- Receptors, Histamine H1/metabolism
- Receptors, Histamine H4
- Treatment Outcome
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Affiliation(s)
- Yusuke Ohsawa
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Miyagi, Japan
| | - Noriyasu Hirasawa
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Miyagi, Japan
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Corrêa MF, dos Santos Fernandes JP. Histamine H4 receptor ligands: future applications and state of art. Chem Biol Drug Des 2014; 85:461-80. [PMID: 25228262 DOI: 10.1111/cbdd.12431] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Histamine is a chemical transmitter found practically in whole organism and exerts its effects through the interaction with H1 to H4 histaminergic receptors. Specifically, H4 receptors are found mainly in immune cells and blood-forming tissues, thus are involved in inflammatory and immune processes, as well as some actions in central nervous system. Therefore, H4 receptor ligands can have applications in the treatment of chronic inflammatory and immune diseases and may be novel therapeutic option in these conditions. Several H4 receptor ligands have been described from early 2000's until nowadays, being imidazole, indolecarboxamide, 2-aminopyrimidine, quinazoline, and quinoxaline scaffolds the most explored and discussed in this review. Moreover, several studies of molecular modeling using homology models of H4 receptor and QSAR data of the ligands are summarized. The increasing and promising therapeutic applications are leading these compounds to clinical trials, which probably will be part of the next generation of blockbuster drugs.
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Affiliation(s)
- Michelle Fidelis Corrêa
- Departamento de Ciências Exatas e da Terra, Instituto de Ciências Ambientais, Químicas e Farmacêuticas, UNIFESP, Diadema, Brazil
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Salem A, Al-Samadi A, Stegajev V, Stark H, Häyrinen-Immonen R, Ainola M, Hietanen J, Konttinen YT. Histamine H4 receptor in oral lichen planus. Oral Dis 2014; 21:378-85. [PMID: 25207698 DOI: 10.1111/odi.12290] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 09/03/2014] [Accepted: 09/03/2014] [Indexed: 01/21/2023]
Abstract
OBJECTIVES Oral lichen planus (OLP) is an autoimmune disease characterized by a band-like T-cell infiltrate below the apoptotic epithelial cells and degenerated basement membrane. We tested the hypothesis that the high-affinity histamine H4 receptors (H4 Rs) are downregulated in OLP by high histamine concentrations and proinflammatory T-cell cytokines. MATERIALS AND METHODS Immunohistochemistry and immunofluorescence staining, image analysis and quantitative real-time polymerase chain reaction of tissue samples and cytokine-stimulated cultured SCC-25 and primary human oral keratinocytes. RESULTS H4 R immunoreactivity was weak in OLP and characterized by mast cell (MC) hyperplasia and degranulation. In contrast to controls, H4 R immunostaining and MC counts were negatively correlated in OLP (P = 0.003). H4 R agonist at nanomolar levels led to a rapid internalization of H4 Rs, whereas high histamine concentration and interferon-γ decreased HRH4 -gene transcripts. CONCLUSION Healthy oral epithelial cells are equipped with H4 R, which displays a uniform staining pattern in a MC-independent fashion. In contrast, in OLP, increased numbers of activated MCs associate with increasing loss of epithelial H4 R. Cell culture experiments suggest a rapid H4 R stimulation-dependent receptor internalization and a slow cytokine-driven decrease in H4 R synthesis. H4 R may be involved in the maintenance of healthy oral mucosa. In OLP, this maintenance might be impaired by MC degranulation and inflammatory cytokines.
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Affiliation(s)
- A Salem
- Department of Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland; Department of Oral Pathology, University of Helsinki, Helsinki, Finland
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Suwa E, Yamaura K, Sato S, Ueno K. Increased expression of the histamine H4 receptor following differentiation and mediation of the H4 receptor on interleukin-8 mRNA expression in HaCaT keratinocytes. Exp Dermatol 2014; 23:138-40. [PMID: 24372819 DOI: 10.1111/exd.12313] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2013] [Indexed: 01/17/2023]
Abstract
Recent in vivo studies have demonstrated involvement of the histamine H4 receptor in pruritus and skin inflammation. We previously reported that an H4 receptor antagonist attenuated scratching behaviour and improved skin lesions in an experimental model of atopic dermatitis. We also reported the expression of the H4 receptor in human epidermal tissues. In this study, we investigated the expression of H4 receptor mRNA and the function of the receptor in a culture system that mimics in vivo inflammation on the HaCaT human keratinocyte cell line. Increased expression of the H4 receptor was observed in HaCaT cells following differentiation. Treatment of HaCaT cells with histamine and TNFα enhanced the mRNA expression of interleukin (IL)-8. These increases in expression were significantly inhibited by the H4 receptor antagonist JNJ7777120. Our results indicate that IL-8 mRNA expression might be enhanced by histamine and TNFα via H4 receptor stimulation in keratinocytes.
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Affiliation(s)
- Eriko Suwa
- Department of Geriatric Pharmacology and Therapeutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba, Japan
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