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Critical Players and Therapeutic Targets in Chronic Itch. Int J Mol Sci 2022; 23:ijms23179935. [PMID: 36077340 PMCID: PMC9456029 DOI: 10.3390/ijms23179935] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/28/2022] [Accepted: 08/29/2022] [Indexed: 12/04/2022] Open
Abstract
Chronic itch is one of the most prominent clinical characteristics of diverse systematic diseases. It is a devastating sensation in pathological diseases. Despite its importance, there are no FDA-labelled drugs specifically geared toward chronic itch. The associated complex pathogenesis and diverse causes escalate chronic itch to being one of the top challenges in healthcare. Humanized antibodies against IL-13, IL-4, and IL-31 proved effective in treatment of itch-associated atopic dermatitis but remain to be validated in chronic itch. There are still no satisfactory anti-itch therapeutics available toward itch-related neuropeptides including GRP, BNP, SST, CGRP, and SP. The newly identified potential itch targets including OSM, NMB, glutamate, periostin, and Serpin E1 have opened new avenues for therapeutic development. Proof-of-principle studies have been successfully performed on antagonists against these proteins and their receptors in itch treatment in animal models. Their translational interventions in humans need to be evaluated. It is of great importance to summarize and compare the newly emerging knowledge on chronic itch and its pathways to promote the development of novel anti-itch therapeutics. The goal of this review is to analyze the different physiologies and pathophysiologies of itch mediators, whilst assessing their suitability as new targets and discussing future therapeutic development.
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Zhang J, Zhou H, Li P, Shi H, Sui X, Wang Y, Shi J, Wang L. Hypothalamic response with PKA/CREB signaling is associated with direct cerebroventricular administration of bombesin-induced scratching. Brain Res 2022; 1789:147950. [PMID: 35618015 DOI: 10.1016/j.brainres.2022.147950] [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: 12/19/2021] [Revised: 04/29/2022] [Accepted: 05/19/2022] [Indexed: 11/28/2022]
Abstract
Bombesin (BN) is an itch-specific mediator that causes intense itch-scratching activity in mammals. Although most examinations of BN-induced itch processing have focused on the spinal cord, the involvement of central nervous system mechanisms remains unclear. Here, we investigated how relationships among hypothalamic regions regulate BN-mediated itch-scratch processes. We found that intracerebroventricular (i.c.v.) administration of BN (0.04-4 μg) elicited intense itch scratching in mice, whereas BN (0.4-400 μg) administered via intravenous tail injection failed to evoke a scratching response. Additionally, nalfurafine had no significant effects on BN-induced scratching behavior, indicating that central modulation of BN is distinct from histamine-mediated histaminergic itch and chloroquine-mediated non-histaminergic itch signaling pathways. We labeled BN with a fluorescent tag, 7-nitrobenz-2-oxa-1 (NBD), and traced its fluorescence in the hypothalamus for 30 min following i.c.v. NBD-BN administration. Accordingly, we confirmed that i.c.v. administration of BN enhanced c-Fos expression in the dorsal medial nucleus of the hypothalamus, where neuromedin B receptors and gastrin-releasing peptide receptors are highly expressed. Interestingly, in situ injection of BN into the hypothalamus immediately and robustly induced itch-scratching behavior. Moreover, gene transcripts and western blot assay revealed that BN receptor-dependent PKA/CREB signaling was upregulated in the hypothalamus after i.c.v. administration of BN. Consistently, pretreatment with a PKA inhibitor, Rp-cAMP, significantly reduced BN-induced scratching behavior. Our results indicate that the dorsal medial nucleus of the hypothalamus may be a key nucleus in mediating BN-mediated itch and hypothalamic PKA/CREB signaling is involved in regulating BN-mediated itch.
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Affiliation(s)
- Jingxin Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China; The Key Laboratory of Basic Pharmacology of the Educational Minister, Zunyi Medical University, Zunyi, Guizhou 563000, China.
| | - Hu Zhou
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China.
| | - Pengfei Li
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China.
| | - Huaxiang Shi
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China.
| | - Xin Sui
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China.
| | - Yongan Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China.
| | - Jingshan Shi
- The Key Laboratory of Basic Pharmacology of the Educational Minister, Zunyi Medical University, Zunyi, Guizhou 563000, China.
| | - Liyun Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China.
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Cevikbas F, Lerner EA. Physiology and Pathophysiology of Itch. Physiol Rev 2020; 100:945-982. [PMID: 31869278 PMCID: PMC7474262 DOI: 10.1152/physrev.00017.2019] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 10/31/2019] [Accepted: 12/04/2019] [Indexed: 02/06/2023] Open
Abstract
Itch is a topic to which everyone can relate. The physiological roles of itch are increasingly understood and appreciated. The pathophysiological consequences of itch impact quality of life as much as pain. These dynamics have led to increasingly deep dives into the mechanisms that underlie and contribute to the sensation of itch. When the prior review on the physiology of itching was published in this journal in 1941, itch was a black box of interest to a small number of neuroscientists and dermatologists. Itch is now appreciated as a complex and colorful Rubik's cube. Acute and chronic itch are being carefully scratched apart and reassembled by puzzle solvers across the biomedical spectrum. New mediators are being identified. Mechanisms blur boundaries of the circuitry that blend neuroscience and immunology. Measures involve psychophysics and behavioral psychology. The efforts associated with these approaches are positively impacting the care of itchy patients. There is now the potential to markedly alleviate chronic itch, a condition that does not end life, but often ruins it. We review the itch field and provide a current understanding of the pathophysiology of itch. Itch is a disease, not only a symptom of disease.
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Affiliation(s)
- Ferda Cevikbas
- Dermira, Inc., Menlo Park, California; and Harvard Medical School and the Cutaneous Biology Research Center at Massachusetts General Hospital, Charlestown, Massachusetts
| | - Ethan A Lerner
- Dermira, Inc., Menlo Park, California; and Harvard Medical School and the Cutaneous Biology Research Center at Massachusetts General Hospital, Charlestown, Massachusetts
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Soeberdt M, Kilic A, Abels C. Small molecule drugs for the treatment of pruritus in patients with atopic dermatitis. Eur J Pharmacol 2020; 881:173242. [PMID: 32504692 DOI: 10.1016/j.ejphar.2020.173242] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/20/2020] [Accepted: 05/29/2020] [Indexed: 12/21/2022]
Abstract
Chronic pruritus is a cardinal symptom of the inflammatory skin disease atopic dermatitis (AD). Pathogenic mechanisms in the periphery, spinal cord and the brain have been implicated in AD-related pruritus. Therefore, both systemic and topical administration of drugs could potentially provide relief. Despite efforts to elucidate the mechanisms behind AD-related pruritus and the relative contribution of peripheral nervous system and central nervous system (CNS), specific and successful treatment options have not yet been developed. Several small molecule drugs are currently being investigated to treat AD and AD-related pruritus. These small molecule drugs can be applied systemically but also topically, as they are able to penetrate into the skin due to their small size. Small molecule drugs specifically targeting peripheral itch transmission, e.g. peripherally selective κ-opioid receptors agonists and neurokinin 1 receptors antagonists, have so far been unable to improve AD-related pruritus when applied systemically, possibly because of the lack of CNS activity. Current evidence from clinical and preclinical trials with centrally acting or peripherally selective oral κ-opioid receptors agonists implies that CNS activity is required for an antipruritic effect. CNS activity is, however, directly associated with CNS-mediated side-effects. On the other hand, topical application of small molecules with anti-inflammatory activity such as Janus kinase inhibitors and phosphodiesterase 4 inhibitors, and also of κ-opioid receptor agonists, has shown promising results regarding their ability to reduce AD-related pruritus. In conclusion, topical application of anti-inflammatory compounds appears to be a highly promising strategy for the treatment of AD-related pruritus.
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Affiliation(s)
| | - Ana Kilic
- Dr. August Wolff GmbH & Co. KG Arzneimittel, Bielefeld, Germany
| | - Christoph Abels
- Dr. August Wolff GmbH & Co. KG Arzneimittel, Bielefeld, Germany.
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Kawai J, Mori K, Hirasawa N. Grifola frondosa extract and ergosterol reduce allergic reactions in an allergy mouse model by suppressing the degranulation of mast cells. Biosci Biotechnol Biochem 2019; 83:2280-2287. [PMID: 31412751 DOI: 10.1080/09168451.2019.1654360] [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] [Indexed: 12/15/2022]
Abstract
The increasing number of patients suffering from allergic diseases is a global health problem. Grifola frondosa is an edible mushroom consumed as a health food in Asia, and has recently been reported to have anti-allergic effects. We previously reported that G. frondosa extract (GFE) and its active components, ergosterol and its derivatives, inhibited the antigen-induced activation of RBL-2H3 cells. Here, we demonstrated that GFE and ergosterol also had an inhibitory effect on the degranulation of bone marrow-derived mast cells (BMMCs) and alleviated anaphylactic cutaneous responses in mice. Using an air pouch-type allergic inflammation mouse model, we confirmed that oral administration of GFE and ergosterol suppressed the degranulation of mast cells in vivo. Our findings suggest that G. frondosa, including ergosterol as its active component, reduces type I allergic reactions by suppressing mast cell degranulation in mice, and might be a novel functional food that prevents allergic diseases.
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Affiliation(s)
- Junya Kawai
- Mushroom Research Laboratory, Hokuto Corporation, Nagano, Japan
| | - Koichiro Mori
- Mushroom Research Laboratory, Hokuto Corporation, Nagano, Japan
| | - Noriyasu Hirasawa
- Laboratory of Pathophysiological Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
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Matsumoto Y, Yokoi H, Kimura T, Matsumoto Y, Kawada M, Arae K, Nakae S, Ikeda T, Matsumoto K, Sakurai H, Saito K. Gastrin-Releasing Peptide Is Involved in the Establishment of Allergic Rhinitis in Mice. Laryngoscope 2018; 128:E377-E384. [PMID: 30151920 DOI: 10.1002/lary.27394] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 05/10/2018] [Accepted: 05/29/2018] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Gastrin-releasing peptide (GRP) is a neuropeptide that targets transmembrane-type receptors. Its role in allergic rhinitis (AR) has yet to be investigated. The present study utilized the nasal mucosa of AR model mice to examine GRP and GRP receptor (GRPR) expression levels, localization, and other factors to evaluate their role in AR pathology. STUDY DESIGN In vivo study in an animal model. METHODS GRP and GRPR expression levels were examined in three different AR models established in BALB/c mice. In addition, a GRPR antagonist (RC-3095) was administered to AR mice to investigate its effect. The distribution of GRPR expression on mast cells in the nasal mucosa with AR was examined. Finally, we investigated the inhibitory effect of RC-3095 on allergy symptoms induced by histamine. RESULTS GRP and GRPR were highly expressed in the nasal mucosal epithelium and interstitial tissues surrounding the nasal glands in AR groups according to immunostaining. GRP and GRPR expression as determined by western blotting increased in the nasal mucosa as the degree of nasal sensitization increased. In addition, the average counts of sneezing and nasal rubbing after treatment in the AR + RC-3095 group were significantly lower than those in the AR + nasal saline group. Mast cells often colocalized with GRPR around nasal glands. Moreover, RC-3095 was effective in reducing sneezing induced by histamine. CONCLUSION The GRP-GRPR system is likely to be involved in allergic inflammation. This system may represent a novel therapeutic target for refractory AR. LEVEL OF EVIDENCE NA. Laryngoscope, E377-E384, 2018.
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Affiliation(s)
- Yuma Matsumoto
- Department of Otorhinolaryngology, Kyorin University School of Medicine, Tokyo, Japan
| | - Hidenori Yokoi
- Department of Otorhinolaryngology, Kyorin University School of Medicine, Tokyo, Japan
| | - Toru Kimura
- Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Tokyo, Japan
| | - Yoshifumi Matsumoto
- Department of Otorhinolaryngology, Kyorin University School of Medicine, Tokyo, Japan
| | - Michitsugu Kawada
- Department of Otorhinolaryngology, Kyorin University School of Medicine, Tokyo, Japan
| | - Ken Arae
- Department of Immunology, Faculty of Health Science, Kyorin University, Tokyo, Japan
| | - Susumu Nakae
- Laboratory of Systems Biology, Center for Experimental Medicine and Systems Biology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Tetsuya Ikeda
- Department of Otorhinolaryngology, Kyorin University School of Medicine, Tokyo, Japan
| | - Kenji Matsumoto
- Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Hiroyuki Sakurai
- Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Tokyo, Japan
| | - Koichiro Saito
- Department of Otorhinolaryngology, Kyorin University School of Medicine, Tokyo, Japan
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Steinhoff M, Buddenkotte J, Lerner EA. Role of mast cells and basophils in pruritus. Immunol Rev 2018; 282:248-264. [DOI: 10.1111/imr.12635] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Martin Steinhoff
- Department of Dermatology and Venereology; Hamad Medical Corporation; Doha Qatar
- Translational Research Institute; Hamad Medical Corporation; Doha Qatar
- Weill Cornell Medicine-Qatar; Doha Qatar
- Medical School; Qatar University; Doha Qatar
- Department Of Dermatology and UCD Charles Institute for Translational Dermatology; University College Dublin; Dublin Ireland
| | - Jörg Buddenkotte
- Department of Dermatology and Venereology; Hamad Medical Corporation; Doha Qatar
- Translational Research Institute; Hamad Medical Corporation; Doha Qatar
| | - Ethan A. Lerner
- Cutaneous Biology Research Center; Department of Dermatology; Massachusetts General Hospital/Harvard Medical School; Charlestown MA USA
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8
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Andoh T, Maki T, Li S, Uta D. β2-Microglobulin elicits itch-related responses in mice through the direct activation of primary afferent neurons expressing transient receptor potential vanilloid 1. Eur J Pharmacol 2017; 810:134-140. [PMID: 28687195 DOI: 10.1016/j.ejphar.2017.07.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Revised: 07/03/2017] [Accepted: 07/03/2017] [Indexed: 12/23/2022]
Abstract
Uremic pruritus is an unpleasant symptom in patients undergoing hemodialysis, and the underlying mechanisms remain unclear. β2-Microglobulin (β2-MG) is well-known as an MHC class I molecule and its level is increased in the plasma of patients undergoing hemodialysis. In this study, we investigated whether β2-MG was a pruritogen in mice. Intradermal injections of β2-MG into the rostral back induced scratching in a dose-dependent manner. Intradermal injection of β2-MG into the cheek also elicited scratching, but not wiping. β2-MG-induced scratching was inhibited by the μ-opioid receptor antagonist naltrexone hydrochloride. β2-MG-induced scratching was not inhibited by antagonists of itch-related receptors (e.g., H1 histamine receptor (terfenadine), TP thromboxane receptor (DCHCH), BLT1 leukotriene B4 receptor (CMHVA), and proteinase-activated receptor 2 (FSLLRY-NH2)). However, β2-MG-induced scratching was attenuated in mice desensitized by repeated application of capsaicin and also by a selective transient receptor potential vanilloid 1 (TRPV1) antagonist (BCTC). In addition, β2-MG induced phosphorylation of extracellular signal-regulated kinase (a marker of activated neurons) in primary culture of dorsal root ganglion neurons that expressed TRPV1. These results suggest that β2-MG is a pruritogen and elicits itch-related responses, at least in part, through TRPV1-expressing primary sensory neurons.
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Affiliation(s)
- Tsugunobu Andoh
- Department of Applied Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
| | - Takahito Maki
- Department of Applied Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Sikai Li
- Department of Applied Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Daisuke Uta
- Department of Applied Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
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Yamada Y, Ueda Y, Nakamura A, Kanayama S, Tamura R, Hashimoto K, Matsumoto T, Ishii R. Immediate-type allergic and protease-mediated reactions are involved in scratching behaviour induced by topical application of Dermatophagoides farinae
extract in NC/Nga mice. Exp Dermatol 2017; 27:418-426. [DOI: 10.1111/exd.13322] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2017] [Indexed: 12/25/2022]
Affiliation(s)
- Yoshihito Yamada
- Drug Development Research Laboratories; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
| | - Yuhki Ueda
- Drug Development Research Laboratories; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
| | - Aki Nakamura
- Drug Development Research Laboratories; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
| | - Shoji Kanayama
- Drug Development Research Laboratories; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
| | - Rie Tamura
- Drug Development Research Laboratories; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
| | - Kei Hashimoto
- Drug Development Research Laboratories; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
| | - Tatsumi Matsumoto
- Drug Development Research Laboratories; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
| | - Ritsuko Ishii
- Strategic Research Planning & Management Department; Kyoto R&D Center; Maruho Co., Ltd.; Kyoto Japan
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10
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Lou H, Lu J, Choi EB, Oh MH, Jeong M, Barmettler S, Zhu Z, Zheng T. Expression of IL-22 in the Skin Causes Th2-Biased Immunity, Epidermal Barrier Dysfunction, and Pruritus via Stimulating Epithelial Th2 Cytokines and the GRP Pathway. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2017; 198:2543-2555. [PMID: 28228560 PMCID: PMC5360537 DOI: 10.4049/jimmunol.1600126] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 01/28/2017] [Indexed: 12/27/2022]
Abstract
Increased expression of Th22 cytokine IL-22 is a characteristic finding in atopic dermatitis (AD). However, the specific role of IL-22 in the pathogenesis of AD in vivo has yet to be elucidated. Consistent with observations in human AD, IL-22 was significantly increased in the AD skin of mice after epicutaneous sensitization to house dust mite allergen. Utilizing a skin-specific inducible transgenic system, we show in the present study that expression of IL-22 in the skin of mice caused an AD-like phenotype characterized by chronic pruritic dermatitis associated with Th2-biased local and systemic immune responses, downregulation of epidermal differentiation complex genes, and enhanced dermatitis upon epicutaneous allergen exposure. IL-22 potently induced the expression of gastrin-releasing peptide (GRP), a neuropeptide pruritogen, in dermal immune cells and sensory afferents and in their skin-innervating sensory neurons. IL-22 also differentially upregulated the expression of GRP receptor (GRPR) on keratinocytes of AD skin. The number of GRP+ cells in the skin correlated with the AD severity and the intensity of pruritus. IL-22 directly upregulated the expression of epithelial-derived type 2 cytokines (thymic stromal lymphopoietin and IL-33) and GRP in primary keratinocytes. Furthermore, GRP not only strongly induced thymic stromal lymphopoietin but it also increased the expression of IL-33 and GRPR synergistically with IL-22. Importantly, we found that the expression of GRP was strikingly increased in the skin of patients with AD. These results indicate that IL-22 plays important pathogenic roles in the initiation and development of AD, in part through inducing keratinocyte production of type 2 cytokines and activation of the GRP/GRPR pathway.
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Affiliation(s)
- Hongfei Lou
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
- Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, People's Republic of China
| | - Jingning Lu
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
| | - Eun Byul Choi
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
| | - Min Hee Oh
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
| | - Mingeum Jeong
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
| | - Sara Barmettler
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
| | - Zhou Zhu
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
| | - Tao Zheng
- Section of Allergy and Clinical Immunology, Yale University School of Medicine, New Haven, CT 06510; and
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11
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Lee JS, Han JS, Lee K, Bang J, Lee H. The peripheral and central mechanisms underlying itch. BMB Rep 2017; 49:474-87. [PMID: 27418284 PMCID: PMC5227140 DOI: 10.5483/bmbrep.2016.49.9.108] [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: 07/01/2016] [Indexed: 12/20/2022] Open
Abstract
Itch is one of the most distressing sensations that substantially impair quality of life. It is a cardinal symptom of many skin diseases and is also caused by a variety of systemic disorders. Unfortunately, currently available itch medications are ineffective in many chronic itch conditions, and they often cause undesirable side effects. To develop novel therapeutic strategies, it is essential to identify primary afferent neurons that selectively respond to itch mediators as well as the central nervous system components that process the sensation of itch and initiate behavioral responses. This review summarizes recent progress in the study of itch, focusing on itch-selective receptors, signaling molecules, neuronal pathways from the primary sensory neurons to the brain, and potential decoding mechanisms based on which itch is distinguished from pain. [BMB Reports 2016; 49(9): 474-487]
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Affiliation(s)
- Jae Seung Lee
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Korea
| | | | - Kyeongho Lee
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Korea
| | - Juwon Bang
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Korea
| | - Hyosang Lee
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Korea
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12
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Olivry T, Mayhew D, Paps JS, Linder KE, Peredo C, Rajpal D, Hofland H, Cote-Sierra J. Early Activation of Th2/Th22 Inflammatory and Pruritogenic Pathways in Acute Canine Atopic Dermatitis Skin Lesions. J Invest Dermatol 2016; 136:1961-1969. [PMID: 27342734 DOI: 10.1016/j.jid.2016.05.117] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 05/24/2016] [Accepted: 05/25/2016] [Indexed: 12/16/2022]
Abstract
Determining inflammation and itch pathway activation in patients with atopic dermatitis (AD) is fraught with the inability to precisely assess the age of skin lesions, thus affecting the analysis of time-dependent mediators. To characterize inflammatory events occurring during early experimental acute AD lesions, biopsy samples were collected 6, 24, and 48 hours after epicutaneous application of Dermatophagoides farinae house dust mites to sensitized atopic dogs. The skin transcriptome was assessed using a dog-specific microarray and quantitative PCR. Acute canine AD skin lesions had a significant up-regulation of genes encoding T helper (Th) 2 (e.g., IL4, IL5, IL13, IL31, and IL33), Th9 (IL9), and Th22 (IL22) cytokines as well as Th2-promoting chemokines such as CCL5 and CCL17. Proinflammatory (e.g., IL6, LTB, and IL18) cytokines were also up-regulated. Other known pruritogenic pathways were also activated: there was significant up-regulation of genes encoding proteases cathepsin S (CTSS), mast cell chymase (CMA1), tryptase (TPS1) and mastin, neuromedin-B (NMB), nerve growth factor (NGF), and leukotriene-synthesis enzymes (ALOX5, ALOX5AP, and LTA4H). Experimental acute canine house dust mite-induced AD lesions exhibit an activation of innate and adaptive immune responses and pruritogenic pathways similar to those seen in humans with acute AD, thereby validating this model to test innovative therapeutics modalities for this disease.
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Affiliation(s)
- Thierry Olivry
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, North Carolina, USA
| | - David Mayhew
- Computational Biology, Target Sciences, GlaxoSmithKline, King of Prussia, Pennsylvania, USA
| | - Judy S Paps
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Keith E Linder
- Comparative Medicine Institute, North Carolina State University, Raleigh, North Carolina, USA; Department of Population Health and Pathobiology, College of Veterinary Medicine, Research Triangle Park, North Carolina, USA
| | - Carlos Peredo
- Stiefel, GlaxoSmithKline, Research Triangle Park, North Carolina, USA.
| | - Deepak Rajpal
- Safety Assessment, Platform Technology and Science, GlaxoSmithKline, Research Triangle Park, NC, USA
| | - Hans Hofland
- Stiefel, GlaxoSmithKline, Research Triangle Park, North Carolina, USA
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13
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Hoeck EA, Marker JB, Gazerani P, H. Andersen H, Arendt-Nielsen L. Preclinical and human surrogate models of itch. Exp Dermatol 2016; 25:750-7. [DOI: 10.1111/exd.13078] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Emil A. Hoeck
- SMI; Department of Health Science and Technology; Faculty of Medicine; Aalborg University; Aalborg E Denmark
| | - Jens B. Marker
- SMI; Department of Health Science and Technology; Faculty of Medicine; Aalborg University; Aalborg E Denmark
| | - Parisa Gazerani
- SMI; Department of Health Science and Technology; Faculty of Medicine; Aalborg University; Aalborg E Denmark
| | - Hjalte H. Andersen
- SMI; Department of Health Science and Technology; Faculty of Medicine; Aalborg University; Aalborg E Denmark
| | - Lars Arendt-Nielsen
- SMI; Department of Health Science and Technology; Faculty of Medicine; Aalborg University; Aalborg E Denmark
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Shimizu K, Andoh T, Yoshihisa Y, Shimizu T. Histamine Released from Epidermal Keratinocytes Plays a Role in α-Melanocyte–Stimulating Hormone-Induced Itching in Mice. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:3003-10. [DOI: 10.1016/j.ajpath.2015.07.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 07/01/2015] [Accepted: 07/14/2015] [Indexed: 10/23/2022]
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15
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Patricio ES, Costa R, Figueiredo CP, Gers-Barlag K, Bicca MA, Manjavachi MN, Segat GC, Gentry C, Luiz AP, Fernandes ES, Cunha TM, Bevan S, Calixto JB. Mechanisms Underlying the Scratching Behavior Induced by the Activation of Proteinase-Activated Receptor-4 in Mice. J Invest Dermatol 2015; 135:2484-2491. [DOI: 10.1038/jid.2015.183] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 04/20/2015] [Accepted: 04/27/2015] [Indexed: 02/08/2023]
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Yawata T, Higashi Y, Shimizu T, Shimizu S, Nakamura K, Taniuchi K, Ueba T, Saito M. Brain opioid and nociceptin receptors are involved in regulation of bombesin-induced activation of central sympatho-adrenomedullary outflow in the rat. Mol Cell Biochem 2015; 411:201-11. [DOI: 10.1007/s11010-015-2582-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 09/26/2015] [Indexed: 11/28/2022]
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Tirado-Sánchez A, Bonifaz A, Ponce-Olivera RM. Serum gastrin-releasing peptide levels correlate with disease severity and pruritus in patients with atopic dermatitis. Br J Dermatol 2015; 173:298-300. [PMID: 25524083 DOI: 10.1111/bjd.13622] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A Tirado-Sánchez
- Dermatology Department, Hospital General de México, Dr. Balmis 148, Col. Doctores, Cuauhtémoc, Ciudad de México, D.F, Mexico. .,Dermatology Department, Instituto Mexicano del Seguro Social, Av. Paseo de la Reforma 476, Planta Baja, Cuauhtémoc, Juárez, 06600, Ciudad de México, D.F, Mexico.
| | - A Bonifaz
- Dermatology Department, Hospital General de México, Dr. Balmis 148, Col. Doctores, Cuauhtémoc, Ciudad de México, D.F, Mexico
| | - R M Ponce-Olivera
- Dermatology Department, Hospital General de México, Dr. Balmis 148, Col. Doctores, Cuauhtémoc, Ciudad de México, D.F, Mexico
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Mediators of Chronic Pruritus in Atopic Dermatitis: Getting the Itch Out? Clin Rev Allergy Immunol 2015; 51:263-292. [DOI: 10.1007/s12016-015-8488-5] [Citation(s) in RCA: 200] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Cowan A, Kehner GB, Inan S. Targeting Itch with Ligands Selective for κ Opioid Receptors. Handb Exp Pharmacol 2015; 226:291-314. [PMID: 25861786 DOI: 10.1007/978-3-662-44605-8_16] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Several chemically diverse pruritogens, including bombesin, compound 48/80, norbinaltorphimine, and 5'-GNTI, cause rodents to scratch excessively in a stable, uniform manner and consequently provide convenient animal models of itch against which potential antipruritics may be evaluated, structure-activity relationships established, and the nature of spontaneous, repetitive behavior itself analyzed. Decreasing the number of scratching bouts in these apparently simple models has been the requisite first step in the progress of kappa opioid agonists such as nalbuphine, asimadoline, and CR845 toward clinical testing as antipruritics. Nalfurafine is the prime example of a kappa agonist spanning the developmental divide between scratching mice models and commercialization within 10 years. Patients undergoing hemodialysis and suffering from the itching associated with uremic pruritus, and potentially those inflicted with atopic dermatitis, are the beneficiaries.
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Affiliation(s)
- Alan Cowan
- Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA, 19140, USA,
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Takanami K, Sakamoto H. The Gastrin-Releasing Peptide Receptor (GRPR) in the Spinal Cord as a Novel Pharmacological Target. Curr Neuropharmacol 2014; 12:434-43. [PMID: 25426011 PMCID: PMC4243033 DOI: 10.2174/1570159x12666140923201432] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/28/2014] [Accepted: 09/10/2014] [Indexed: 12/02/2022] Open
Abstract
Gastrin-releasing peptide (GRP) is a mammalian neuropeptide that acts through the G protein-coupled receptor, GRP receptor (GRPR). Increasing evidence indicates that GRPR-mediated signaling in the central nervous system plays an important role in many physiological processes in mammals. Additionally, we have recently reported that the GRP system within the lumbosacral spinal cord not only controls erection but also triggers ejaculation in male rats. This system of GRP neurons is sexually dimorphic, being prominent in male rats but vestigial or absent in females. It is suggested that the sexually dimorphic GRP/GRPR system in the lumbosacral spinal cord plays a critical role in the regulation of male sexual function. In parallel, it has been reported that the somatosensory GRP/GRPR system in the spinal cord contributes to the regulation of itch specific transmission independently of the pain transmission. Interestingly, these two distinct functions in the same spinal region are both regulated by the neuropeptide, GRP. In this report, we review findings on recently identified GRP/GRPR systems in the spinal cord. These GRP/GRPR systems in the spinal cord provide new insights into pharmacological treatments for psychogenic erectile dysfunction as well as for chronic pruritus.
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Affiliation(s)
- Keiko Takanami
- Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Hirotaka Sakamoto
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, Ushimado, Setouchi, Okayama 701-4303, Japan
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Akiyama T, Tominaga M, Takamori K, Carstens MI, Carstens E. Role of spinal bombesin-responsive neurons in nonhistaminergic itch. J Neurophysiol 2014; 112:2283-9. [PMID: 25122701 DOI: 10.1152/jn.00409.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Intrathecal administration of the neurotoxin bombesin-saporin reduces or abolishes pruritogen-evoked scratching behavior. We investigated whether spinal neurons that respond to intradermal (ID) injection of pruritogens also respond to spinal superfusion of bombesin and vice versa. Single-unit recordings were made from superficial lumbar spinal dorsal horn neurons in anesthetized mice. We identified neurons with three search strategies: 1) ID injection of the nonhistaminergic itch mediator chloroquine, 2) spinal superfusion of bombesin, and 3) noxious pinch. All units were tested with an array of itch mediators (chloroquine, histamine, SLIGRL, BAM8-22), algogens [capsaicin, allyl isothiocyanate (AITC)], and physical stimuli (brush, pinch, noxious heat, cooling) applied to the hindlimb receptive field. The vast majority of chloroquine-responsive units also responded to bombesin. Of 26 chloroquine-sensitive units tested, most responded to SLIGRL, half responded to histamine and/or BAM8-22, and most responded to capsaicin and/or AITC as well as noxious thermal and mechanical stimuli. Of 29 bombesin-responsive units, a large majority also responded to other itch mediators as well as AITC, capsaicin, and noxious thermal and mechanical stimuli. Responses to successive applications of bombesin exhibited tachyphylaxis. In contrast, of 36 units responsive to noxious pinch, the majority (67%) did not respond to ID chloroquine or spinal bombesin. It is suggested that chloroquine- and bombesin-sensitive spinal neurons signal itch from the skin.
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Affiliation(s)
- Tasuku Akiyama
- Temple Itch Center, Department of Dermatology and Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, Pennsylvania; and
| | - Mitsutoshi Tominaga
- Institute for Environmental and Gender Specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Kenji Takamori
- Institute for Environmental and Gender Specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Mirela Iodi Carstens
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, California;
| | - E Carstens
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, California
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Tominaga M, Takamori K. Itch and nerve fibers with special reference to atopic dermatitis: Therapeutic implications. J Dermatol 2014; 41:205-12. [DOI: 10.1111/1346-8138.12317] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 09/13/2013] [Indexed: 01/10/2023]
Affiliation(s)
- Mitsutoshi Tominaga
- Institute for Environmental and Gender Specific Medicine; Juntendo University Graduate School of Medicine; Urayasu Chiba Japan
| | - Kenji Takamori
- Institute for Environmental and Gender Specific Medicine; Juntendo University Graduate School of Medicine; Urayasu Chiba Japan
- Department of Dermatology; Juntendo University Urayasu Hospital; Urayasu Chiba Japan
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Chéret J, Lebonvallet N, Carré JL, Misery L, Le Gall-Ianotto C. Role of neuropeptides, neurotrophins, and neurohormones in skin wound healing. Wound Repair Regen 2013; 21:772-88. [PMID: 24134750 DOI: 10.1111/wrr.12101] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 07/01/2013] [Indexed: 12/01/2022]
Abstract
Due to the close interactions between the skin and peripheral nervous system, there is increasing evidence that the cutaneous innervation is an important modulator of the normal wound healing process. The communication between sensory neurons and skin cells involves a variety of molecules (neuropeptides, neurohormones, and neurotrophins) and their specific receptors expressed by both neuronal and nonneuronal skin cells. It is well established that neurotransmitters and nerve growth factors released in skin have immunoregulatory roles and can exert mitogenic actions; they could also influence the functions of the different skin cell types during the wound healing process.
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Affiliation(s)
- Jérémy Chéret
- Laboratory of Neurosciences of Brest (EA4685), University of Western Brittany, Brest, France
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Abstract
While considerable effort has been made to investigate the neural mechanisms of pain, much less effort has been devoted to itch, at least until recently. However, itch is now gaining increasing recognition as a widespread and costly medical and socioeconomic issue. This is accompanied by increasing interest in the underlying neural mechanisms of itch, which has become a vibrant and rapidly-advancing field of research. The goal of the present forefront review is to describe the recent progress that has been made in our understanding of itch mechanisms.
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Affiliation(s)
- Tasuku Akiyama
- University of California, Davis, Department of Neurobiology, Physiology & Behavior, 1 Shields Avenue, Davis, CA 95616, United States
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Abstract
INTRODUCTION Chronic pruritus (CP), defined as itch lasting for > 6 weeks, is a burdensome symptom of several different diseases, dermatological and systemic, with a high negative impact on the quality of life of patients. Given the manifold aetiologies of CP, therapy is often difficult. In recent years, however, novel substances have been developed for treatment of certain CP entities and identified targets. AREAS COVERED In this review, the authors present a survey of targets currently believed to be promising (H4R, IL-31, MOR, KOR, GRPR, NGF, NK-1R, TRP channels) and related investigational drugs that are in the preclinical or clinical stage of development. Some substances have already undergone clinical testing, but only one of them (nalfurafine) has been licensed so far. Many of them are most likely to exert their effects on the skin and interfere there with the cutaneous neurobiology of CP. EXPERT OPINION Currently, the most promising candidates for new therapeutic agents in CP are neurokinin-1 receptor antagonists and substances targeting the kappa- or mu-opioid receptor, or both. They have the potential to target the neuronal pathway of CP and are thus of interest for several CP entities. The goal for the coming years is to validate these concepts and move forward in developing new drugs for the therapy of CP.
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Affiliation(s)
- Heike Benecke
- University Medicine Göttingen, Center Nanoscale Microscopy and Molecular Physiology of the Brain, Humboldtallee 23, 37073 Göttingen, Germany
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Sukhtankar DD, Ko MC. Physiological function of gastrin-releasing peptide and neuromedin B receptors in regulating itch scratching behavior in the spinal cord of mice. PLoS One 2013; 8:e67422. [PMID: 23826298 PMCID: PMC3691251 DOI: 10.1371/journal.pone.0067422] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 05/17/2013] [Indexed: 01/01/2023] Open
Abstract
Pruritus (itch) is a severe side effect associated with the use of drugs as well as hepatic and hematological disorders. Previous studies in rodents suggest that bombesin receptor subtypes i.e. receptors for gastrin-releasing peptide (GRPr) and neuromedin B (NMBr) differentially regulate itch scratching. However, to what degree spinal GRPr and NMBr regulate scratching evoked by intrathecally administered bombesin-related peptides is not known. The first aim of this study was to pharmacologically compare the dose-response curves for scratching induced by intrathecally administered bombesin-related peptides versus morphine, which is known to elicit itch in humans. The second aim was to determine if spinal GRPr and NMBr selectively or generally mediate scratching behavior. Mice received intrathecal injection of bombesin (0.01-0.3 nmol), GRP (0.01-0.3 nmol), NMB (0.1-1 nmol) or morphine (0.3-3 nmol) and were observed for one hour for scratching activity. Bombesin elicited most profound scratching over one hour followed by GRP and NMB, whereas morphine failed to evoke scratching response indicating the insensitivity of mouse models to intrathecal opioid-induced itch. Intrathecal pretreatment with GRPr antagonist RC-3095 (0.03-0.1 nmol) produced a parallel rightward shift in the dose response curve of GRP-induced scratching but not NMB-induced scratching. Similarly, PD168368 (1-3 nmol) only attenuated NMB but not GRP-induced scratching. Individual or co-administration of RC-3095 and PD168368 failed to alter bombesin-evoked scratching. A higher dose of RC-3095 (0.3 nmol) generally suppressed scratching induced by all three peptides but also compromised motor function in the rotarod test. Together, these data indicate that spinal GRPr and NMBr independently drive itch neurotransmission in mice and may not mediate bombesin-induced scratching. GRPr antagonists at functionally receptor-selective doses only block spinal GRP-elicited scratching but the suppression of scratching at higher doses is confounded by motor impairment.
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Affiliation(s)
- Devki D. Sukhtankar
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Mei-Chuan Ko
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, United States of America
- * E-mail:
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Liu T, Ji RR. New insights into the mechanisms of itch: are pain and itch controlled by distinct mechanisms? Pflugers Arch 2013; 465:1671-85. [PMID: 23636773 DOI: 10.1007/s00424-013-1284-2] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Revised: 04/13/2013] [Accepted: 04/14/2013] [Indexed: 12/30/2022]
Abstract
Itch and pain are closely related but distinct sensations. They share largely overlapping mediators and receptors, and itch-responding neurons are also sensitive to pain stimuli. Itch-mediating primary sensory neurons are equipped with distinct receptors and ion channels for itch transduction, including Mas-related G protein-coupled receptors (Mrgprs), protease-activated receptors, histamine receptors, bile acid receptor, toll-like receptors, and transient receptor potential subfamily V1/A1 (TRPV1/A1). Recent progress has indicated the existence of an itch-specific neuronal circuitry. The MrgprA3-expressing primary sensory neurons exclusively innervate the epidermis of skin, and their central axons connect with gastrin-releasing peptide receptor (GRPR)-expressing neurons in the superficial spinal cord. Notably, ablation of MrgprA3-expressing primary sensory neurons or GRPR-expressing spinal cord neurons results in selective reduction in itch but not pain. Chronic itch results from dysfunction of the immune and nervous system and can manifest as neural plasticity despite the fact that chronic itch is often treated by dermatologists. While differences between acute pain and acute itch are striking, chronic itch and chronic pain share many similar mechanisms, including peripheral sensitization (increased responses of primary sensory neurons to itch and pain mediators), central sensitization (hyperactivity of spinal projection neurons and excitatory interneurons), loss of inhibitory control in the spinal cord, and neuro-immune and neuro-glial interactions. Notably, painful stimuli can elicit itch in some chronic conditions (e.g., atopic dermatitis), and some drugs for treating chronic pain are also effective in chronic itch. Thus, itch and pain have more similarities in pathological and chronic conditions.
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Affiliation(s)
- Tong Liu
- Pain Signaling and Plasticity Laboratory, Department of Anesthesiology and Neurobiology, Duke University Medical Center, 595 LaSalle Street, GSRB-I, Room 1027A, DUMC 3094, Durham, NC, 27710, USA,
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Overexpression of the gastrin-releasing peptide in cutaneous nerve fibers and its receptor in the spinal cord in primates with chronic itch. J Invest Dermatol 2013; 133:2489-2492. [PMID: 23558404 PMCID: PMC3737283 DOI: 10.1038/jid.2013.166] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Serum gastrin-releasing peptide levels correlate with pruritus in patients with atopic dermatitis. J Invest Dermatol 2013; 133:1673-5. [PMID: 23353988 DOI: 10.1038/jid.2013.38] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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30
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Affiliation(s)
- Yasushi Kuraishi
- Laboratory of Applied Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama
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Tominaga M, Takamori K. An Update on Peripheral Mechanisms and Treatments of Itch. Biol Pharm Bull 2013; 36:1241-7. [DOI: 10.1248/bpb.b13-00319] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Mitsutoshi Tominaga
- Institute for Environmental and Gender Specific Medicine, Graduate School of Medicine, Juntendo University
| | - Kenji Takamori
- Institute for Environmental and Gender Specific Medicine, Graduate School of Medicine, Juntendo University
- Department of Dermatology, Juntendo University Urayasu Hospital
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Akiyama T, Tominaga M, Davoodi A, Nagamine M, Blansit K, Horwitz A, Carstens MI, Carstens E. Roles for substance P and gastrin-releasing peptide as neurotransmitters released by primary afferent pruriceptors. J Neurophysiol 2012; 109:742-8. [PMID: 23155177 DOI: 10.1152/jn.00539.2012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recent studies support roles for neurokinin-1 (NK-1) and gastrin-releasing peptide (GRP) receptor-expressing spinal neurons in itch. We presently investigated expression of substance P (SP) and GRP in pruritogen-responsive primary sensory neurons and roles for these neuropeptides in itch signaling. Responses of dorsal root ganglion (DRG) cells to various pruritogens were observed by calcium imaging. DRG cells were then processed for SP, GRP, and isolectin B-4 (IB4; a marker for nonpeptidergic neurons) immunofluorescence. Of pruritogen-responsive DRG cells, 11.8-26.8%, 21.8-40.0%, and 21.4-26.8% were immunopositive for SP, GRP, and IB4, respectively. In behavioral studies, both systemic and intrathecal administration of a NK-1 receptor antagonist significantly attenuated scratching evoked by chloroquine and a protease-activated receptor 2 agonist, SLIGRL, but not histamine, bovine adrenal medulla peptide 8-22 (BAM8-22), or serotonin. Systemic or intrathecal administration of a GRP receptor antagonist attenuated scratching evoked by chloroquine and SLIGRL but not BAM8-22 or histamine. The GRP receptor antagonist enhanced scratching evoked by serotonin. These results indicate that SP and GRP expressed in primary sensory neurons are partially involved as neurotransmitters in histamine-independent itch signaling from the skin to the spinal cord.
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Affiliation(s)
- Tasuku Akiyama
- Dept. of Neurobiology, Physiology & Behavior, Univ. of California, Davis, Davis, CA 95616, USA
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Kuraishi Y. [Mechanisms of itch and the pharmacology of anti-pruritic agents]. Nihon Yakurigaku Zasshi 2012; 139:160-164. [PMID: 22498680 DOI: 10.1254/fpj.139.160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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