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Mießner H, Seidel J, Smith ESJ. In vitro models for investigating itch. Front Mol Neurosci 2022; 15:984126. [PMID: 36385768 PMCID: PMC9644192 DOI: 10.3389/fnmol.2022.984126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 10/10/2022] [Indexed: 12/04/2022] Open
Abstract
Itch (pruritus) is a sensation that drives a desire to scratch, a behavior observed in many animals. Although generally short-lasting and not causing harm, there are several pathological conditions where chronic itch is a hallmark symptom and in which prolonged scratching can induce damage. Finding medications to counteract the sensation of chronic itch has proven difficult due to the molecular complexity that involves a multitude of triggers, receptors and signaling pathways between skin, immune and nerve cells. While much has been learned about pruritus from in vivo animal models, they have limitations that corroborate the necessity for a transition to more human disease-like models. Also, reducing animal use should be encouraged in research. However, conducting human in vivo experiments can also be ethically challenging. Thus, there is a clear need for surrogate models to be used in pre-clinical investigation of the mechanisms of itch. Most in vitro models used for itch research focus on the use of known pruritogens. For this, sensory neurons and different types of skin and/or immune cells are stimulated in 2D or 3D co-culture, and factors such as neurotransmitter or cytokine release can be measured. There are however limitations of such simplistic in vitro models. For example, not all naturally occurring cell types are present and there is also no connection to the itch-sensing organ, the central nervous system (CNS). Nevertheless, in vitro models offer a chance to investigate otherwise inaccessible specific cell–cell interactions and molecular pathways. In recent years, stem cell-based approaches and human primary cells have emerged as viable alternatives to standard cell lines or animal tissue. As in vitro models have increased in their complexity, further opportunities for more elaborated means of investigating itch have been developed. In this review, we introduce the latest concepts of itch and discuss the advantages and limitations of current in vitro models, which provide valuable contributions to pruritus research and might help to meet the unmet clinical need for more refined anti-pruritic substances.
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Affiliation(s)
- Hendrik Mießner
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
- Dermatological Skin Care, Beiersdorf AG, Hamburg, Germany
| | - Judith Seidel
- Dermatological Skin Care, Beiersdorf AG, Hamburg, Germany
| | - Ewan St. John Smith
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
- *Correspondence: Ewan St. John Smith,
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2
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Tominaga M, Takamori K. Peripheral itch sensitization in atopic dermatitis. Allergol Int 2022; 71:265-277. [PMID: 35624035 DOI: 10.1016/j.alit.2022.04.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 04/06/2022] [Indexed: 02/07/2023] Open
Abstract
Atopic dermatitis is a skin disorder caused by skin dryness and barrier dysfunction, resulting in skin inflammation and chronic itch (or pruritus). The pathogenesis of atopic dermatitis is thought to be initiated by a lowering of the itch threshold due to dry skin. This lowering of the itch threshold is at least partially due to the increase in intraepidermal nerve fibers and sensitization of sensory nerves by interleukin (IL)-33 produced and secreted by keratinocytes. Such skin is easily prone to itch due to mechanical stimuli, such as rubbing of clothing and chemical stimuli from itch mediators. In patients with atopic dermatitis, once itch occurs, further itch is induced by scratching, and the associated scratching breaks down the skin barrier. Disruption of the skin barrier allows entry into the epidermis of external foreign substances, such as allergens derived from house dust mites, leading to an increased induction of type 2 inflammatory responses. As a result, type 2 cytokines IL-4, IL-13, and IL-31 are mainly secreted by Th2 cells, and their action on sensory nerve fibers causes further itch sensitization. These sequences of events are thought to occur simultaneously in patients with atopic dermatitis, leading to a vicious itch-scratch cycle. This vicious cycle becomes a negative spiral that leads to disease burden. Therefore, controlling itch is essential for the treatment of atopic dermatitis. In this review, we summarize and discuss advances in the mechanisms of peripheral itch sensitization in atopic dermatitis, focusing on skin barrier-neuro-immune triadic connectivity.
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3
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Mitsuishi T, Tominaga M, Miyata K, Toyama S, Kimura U, Suga Y, Takamori K. Excimer light therapy with systemic corticosteroids improved severe chronic nodular prurigo and altered peripheral nerve fibers in the epidermis. Lasers Med Sci 2022; 37:3727-3731. [PMID: 35508565 DOI: 10.1007/s10103-022-03570-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 04/25/2022] [Indexed: 10/18/2022]
Affiliation(s)
- Tsuyoshi Mitsuishi
- Department of Dermatology, Tokyo Women's Medical University Yachiyo Medical Center, Chiba, Japan. .,Department of Dermatology, Japanese Red Cross Saitama Hospital, 1-5 Shintoshin, Chuo-ku, Saitama, Japan.
| | - Mitsutoshi Tominaga
- Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Kazunori Miyata
- Department of Dermatology, Tokyo Women's Medical University Yachiyo Medical Center, Chiba, Japan
| | - Sumika Toyama
- Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Utako Kimura
- Department of Dermatology, Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan
| | - Yasushi Suga
- Department of Dermatology, Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan
| | - Kenji Takamori
- Juntendo Itch Research Center (JIRC), 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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4
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Evtushenko NA, Beilin AK, Kosykh AV, Vorotelyak EA, Gurskaya NG. Keratins as an Inflammation Trigger Point in Epidermolysis Bullosa Simplex. Int J Mol Sci 2021; 22:ijms222212446. [PMID: 34830328 PMCID: PMC8624175 DOI: 10.3390/ijms222212446] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 11/11/2021] [Accepted: 11/12/2021] [Indexed: 12/21/2022] Open
Abstract
Epidermolysis bullosa simplex (EBS) is a group of inherited keratinopathies that, in most cases, arise due to mutations in keratins and lead to intraepidermal ruptures. The cellular pathology of most EBS subtypes is associated with the fragility of the intermediate filament network, cytolysis of the basal layer of the epidermis, or attenuation of hemidesmosomal/desmosomal components. Mutations in keratins 5/14 or in other genes that encode associated proteins induce structural disarrangements of different strengths depending on their locations in the genes. Keratin aggregates display impaired dynamics of assembly and diminished solubility and appear to be the trigger for endoplasmic reticulum (ER) stress upon being phosphorylated by MAPKs. Global changes in cellular signaling mainly occur in cases of severe dominant EBS mutations. The spectrum of changes initiated by phosphorylation includes the inhibition of proteasome degradation, TNF-α signaling activation, deregulated proliferation, abnormal cell migration, and impaired adherence of keratinocytes. ER stress also leads to the release of proinflammatory danger-associated molecular pattern (DAMP) molecules, which enhance avalanche-like inflammation. Many instances of positive feedback in the course of cellular stress and the development of sterile inflammation led to systemic chronic inflammation in EBS. This highlights the role of keratin in the maintenance of epidermal and immune homeostasis.
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Affiliation(s)
- Nadezhda A. Evtushenko
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Ostrovityanova 1, 117997 Moscow, Russia; (N.A.E.); (A.K.B.); (A.V.K.)
| | - Arkadii K. Beilin
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Ostrovityanova 1, 117997 Moscow, Russia; (N.A.E.); (A.K.B.); (A.V.K.)
- Koltzov Institute of Developmental Biology of Russian Academy of Sciences, Vavilova 26, 119334 Moscow, Russia;
| | - Anastasiya V. Kosykh
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Ostrovityanova 1, 117997 Moscow, Russia; (N.A.E.); (A.K.B.); (A.V.K.)
| | - Ekaterina A. Vorotelyak
- Koltzov Institute of Developmental Biology of Russian Academy of Sciences, Vavilova 26, 119334 Moscow, Russia;
| | - Nadya G. Gurskaya
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Ostrovityanova 1, 117997 Moscow, Russia; (N.A.E.); (A.K.B.); (A.V.K.)
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Miklukho-Maklaya 16/10, 117997 Moscow, Russia
- Correspondence:
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5
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Pompili E, De Franchis V, Giampietri C, Leone S, De Santis E, Fornai F, Fumagalli L, Fabrizi C. Protease Activated Receptor 1 and Its Ligands as Main Regulators of the Regeneration of Peripheral Nerves. Biomolecules 2021; 11:1668. [PMID: 34827666 PMCID: PMC8615415 DOI: 10.3390/biom11111668] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/29/2021] [Accepted: 11/05/2021] [Indexed: 12/16/2022] Open
Abstract
In contrast with the brain and spinal cord, peripheral nerves possess a striking ability to regenerate after damage. This characteristic of the peripheral nervous system is mainly due to a specific population of glial cells, the Schwann cells. Schwann cells promptly activate after nerve injury, dedifferentiate assuming a repair phenotype, and assist axon regrowth. In general, tissue injury determines the release of a variety of proteases which, in parallel with the degradation of their specific targets, also activate plasma membrane receptors known as protease-activated receptors (PARs). PAR1, the prototypical member of the PAR family, is also known as thrombin receptor and is present at the Schwann cell plasma membrane. This receptor is emerging as a possible regulator of the pro-regenerative capacity of Schwann cells. Here, we summarize the most recent literature data describing the possible contribution of PAR1 and PAR1-activating proteases in regulating the regeneration of peripheral nerves.
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Affiliation(s)
- Elena Pompili
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via A. Borelli 50, 00161 Rome, Italy; (V.D.F.); (C.G.); (E.D.S.); (L.F.); (C.F.)
| | - Valerio De Franchis
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via A. Borelli 50, 00161 Rome, Italy; (V.D.F.); (C.G.); (E.D.S.); (L.F.); (C.F.)
| | - Claudia Giampietri
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via A. Borelli 50, 00161 Rome, Italy; (V.D.F.); (C.G.); (E.D.S.); (L.F.); (C.F.)
| | - Stefano Leone
- Department of Science, Roma Tre University, Viale Guglielmo Marconi 446, 00146 Rome, Italy;
| | - Elena De Santis
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via A. Borelli 50, 00161 Rome, Italy; (V.D.F.); (C.G.); (E.D.S.); (L.F.); (C.F.)
| | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy;
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Lorenzo Fumagalli
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via A. Borelli 50, 00161 Rome, Italy; (V.D.F.); (C.G.); (E.D.S.); (L.F.); (C.F.)
| | - Cinzia Fabrizi
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via A. Borelli 50, 00161 Rome, Italy; (V.D.F.); (C.G.); (E.D.S.); (L.F.); (C.F.)
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6
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Misery L, Brenaut E, Pierre O, Le Garrec R, Gouin O, Lebonvallet N, Abasq-Thomas C, Talagas M, Le Gall-Ianotto C, Besner-Morin C, Fluhr JW, Leven C. Chronic itch: emerging treatments following new research concepts. Br J Pharmacol 2021; 178:4775-4791. [PMID: 34463358 DOI: 10.1111/bph.15672] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 08/20/2021] [Accepted: 08/24/2021] [Indexed: 11/29/2022] Open
Abstract
Until recently, itch pathophysiology was poorly understood and treatments were poorly effective in relieving itch. Current progress in our knowledge of the itch processing, the numerous mediators and receptors involved has led to a large variety of possible therapeutic pathways. Currently, inhibitors of IL-31, IL-4/13, NK1 receptors, opioids and cannabinoids, JAK, PDE4 or TRP are the main compounds involved in clinical trials. However, many new targets, such as Mas-related GPCRs and unexpected new pathways need to be also explored.
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Affiliation(s)
- Laurent Misery
- LIEN, Univ Brest, Brest, France.,Department of Dermatology, University Hospital of Brest, Brest, France
| | - Emilie Brenaut
- LIEN, Univ Brest, Brest, France.,Department of Dermatology, University Hospital of Brest, Brest, France
| | | | | | - Olivier Gouin
- LIEN, Univ Brest, Brest, France.,INSERM UMR 1163, Laboratory of Genetic Skin Diseases, Imagine Institute, Paris, France.,University of Paris, Paris, France
| | | | - Claire Abasq-Thomas
- LIEN, Univ Brest, Brest, France.,Department of Dermatology, University Hospital of Brest, Brest, France
| | - Matthieu Talagas
- LIEN, Univ Brest, Brest, France.,Department of Dermatology, University Hospital of Brest, Brest, France
| | | | - Catherine Besner-Morin
- LIEN, Univ Brest, Brest, France.,Department of Dermatology, University Hospital of Brest, Brest, France.,Division of Dermatology, McGill University Health Centre, Montreal General Hospital, Montreal, Quebec, Canada
| | - Joachim W Fluhr
- LIEN, Univ Brest, Brest, France.,Department of Dermatology, University Hospital of Brest, Brest, France.,Department of Dermatology, Charité Universitätsmedizin, Berlin, Germany
| | - Cyril Leven
- LIEN, Univ Brest, Brest, France.,EA3878, FCRIN INNOVTE, groupe d'étude thrombose Bretagne Occidentale, Brest, France.,Department of Biochemistry and Pharmaco-Toxicology, University Hospital of Brest, Brest, France
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7
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Pfisterer K, Shaw LE, Symmank D, Weninger W. The Extracellular Matrix in Skin Inflammation and Infection. Front Cell Dev Biol 2021; 9:682414. [PMID: 34295891 PMCID: PMC8290172 DOI: 10.3389/fcell.2021.682414] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/25/2021] [Indexed: 12/12/2022] Open
Abstract
The extracellular matrix (ECM) is an integral component of all organs and plays a pivotal role in tissue homeostasis and repair. While the ECM was long thought to mostly have passive functions by providing physical stability to tissues, detailed characterization of its physical structure and biochemical properties have uncovered an unprecedented broad spectrum of functions. It is now clear that the ECM not only comprises the essential building block of tissues but also actively supports and maintains the dynamic interplay between tissue compartments as well as embedded resident and recruited inflammatory cells in response to pathologic stimuli. On the other hand, certain pathogens such as bacteria and viruses have evolved strategies that exploit ECM structures for infection of cells and tissues, and mutations in ECM proteins can give rise to a variety of genetic conditions. Here, we review the composition, structure and function of the ECM in cutaneous homeostasis, inflammatory skin diseases such as psoriasis and atopic dermatitis as well as infections as a paradigm for understanding its wider role in human health.
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Affiliation(s)
- Karin Pfisterer
- Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | | | | | - Wolfgang Weninger
- Department of Dermatology, Medical University of Vienna, Vienna, Austria
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8
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Gingival Crevicular Fluid Zinc- and Aspartyl-Binding Protease Profile of Individuals with Moderate/Severe Atopic Dermatitis. Biomolecules 2020; 10:biom10121600. [PMID: 33255937 PMCID: PMC7761491 DOI: 10.3390/biom10121600] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/24/2020] [Accepted: 11/24/2020] [Indexed: 12/28/2022] Open
Abstract
Atopic dermatitis (AD) is a protease-modulated chronic disorder with heterogenous clinical manifestations which may lead to an imprecise diagnosis. To date, there are no diagnostic protease tests for AD. We explored the gingival crevicular fluid (GCF) protease profile of individuals with moderate/severe AD compared to healthy controls. An exploratory case-control study was conducted. AD patients (n = 23) and controls (n = 21) were enrolled at the International Center for Clinical Studies, Santiago, Chile. Complete dermatological and periodontal evaluations (involving the collection of GCF samples) were made. The levels of 35 proteases were analyzed using a human protease antibody array in matching AD patients (n = 6) and controls (n = 6) with healthy periodontium. The GCF levels of zinc-binding ADAM8, ADAM9, MMP8, Neprilysin/CD10, aspartyl-binding Cathepsin E, serin-binding Protein convertase9, and uPA/Urokinase proteases were lower in moderate/severe AD patients compared to controls (p < 0.05). No inter-group differences in the levels of the other 28 proteases were found. MMP8, Cathepsin E, and ADAM9 were the biomarkers with the highest sensitivity and specificity regarding the detection of AD (p < 0.05). The area under receiver operating characteristic (ROC) curve for MMP8 was 0.83 and MMP8 + ADAMP9 was 0.90, with no significant differences (p = 0.132). A combined model of MMP8, Cathepsin E, and ADAM9 was not considered since it did not converge. Then, levels of MMP8 in GCF were determined using a multiplex bead immunoassay in 23 subjects with AD and 21 healthy subjects. Lower levels of MMP8 in the GCF from the AD group versus healthy group (p = 0.029) were found. This difference remained significant after adjustment by periodontitis (p = 0.042). MMP8 revealed the diagnostic potential to identify AD patients versus healthy controls, (ROC area = 0.672, p < 0.05). In conclusion, differences in the protease profile between AD and control patients were associated with MMP8, Cathepsin E, and ADAM9. Based on the multiplex assay results, MMP8 was lower in AD patients than controls, suggesting that MMP8 may be a diagnostic biomarker candidate.
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9
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Xing Y, Chen J, Hilley H, Steele H, Yang J, Han L. Molecular Signature of Pruriceptive MrgprA3 + Neurons. J Invest Dermatol 2020; 140:2041-2050. [PMID: 32234460 DOI: 10.1016/j.jid.2020.03.935] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 02/07/2023]
Abstract
Itch, initiated by the activation of sensory neurons, is associated frequently with dermatological diseases. MrgprA3+ sensory neurons have been identified as one of the major itch-sensing neuronal populations. Mounting evidence has demonstrated that peripheral pathological conditions induce physiological regulation of sensory neurons, which is critical for the maintenance of chronic itch sensation. However, the underlying molecular mechanisms are not clear. Here, we performed RNA sequencing of genetically labeled MrgprA3+ neurons under both naïve and allergic contact dermatitis conditions. Our results revealed the unique molecular signature of itch-sensing neurons and the distinct transcriptional profile changes that result in response to dermatitis. We found enrichment of nine Mrgpr family members and two histamine receptors in MrgprA3+ neurons, suggesting that MrgprA3+ neurons are a direct neuronal target for histamine and Mrgpr agonists. In addition, PTPN6 and PCDH12 were identified as highly selective markers of MrgprA3+ neurons. We also discovered that MrgprA3+ neurons respond to skin dermatitis in a way that is unique from other sensory neurons by regulating a combination of transcriptional factors, ion channels, and key molecules involved in synaptic transmission. These results significantly increase our knowledge of itch transmission and uncover potential targets for combating itch.
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Affiliation(s)
- Yanyan Xing
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Junyu Chen
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Henry Hilley
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Haley Steele
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Jingjing Yang
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Liang Han
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA.
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10
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Sun J, Pan X, Christiansen LI, Yuan XL, Skovgaard K, Chatterton DEW, Kaalund SS, Gao F, Sangild PT, Pankratova S. Necrotizing enterocolitis is associated with acute brain responses in preterm pigs. J Neuroinflammation 2018; 15:180. [PMID: 29885660 PMCID: PMC5994241 DOI: 10.1186/s12974-018-1201-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 05/14/2018] [Indexed: 12/24/2022] Open
Abstract
Background Necrotizing enterocolitis (NEC) is an acute gut inflammatory disorder that occurs in preterm infants in the first weeks after birth. Infants surviving NEC often show impaired neurodevelopment. The mechanisms linking NEC lesions with later neurodevelopment are poorly understood but may include proinflammatory signaling in the immature brain. Using preterm pigs as a model for preterm infants, we hypothesized that severe intestinal NEC lesions are associated with acute effects on the developing hippocampus. Methods Cesarean-delivered preterm pigs (n = 117) were reared for 8 days and spontaneously developed variable severity of NEC lesions. Neonatal arousal, physical activity, and in vitro neuritogenic effects of cerebrospinal fluid (CSF) were investigated in pigs showing NEC lesions in the colon (Co-NEC) or in the small intestine (Si-NEC). Hippocampal transcriptome analysis and qPCR were used to assess gene expressions and their relation to biological processes, including neuroinflammation, and neural plasticity. Microglia activation was quantified by stereology. The neuritogenic response to selected proteins was investigated in primary cultures of hippocampal neurons. Results NEC development rapidly reduced the physical activity of pigs, especially when lesions occurred in the small intestine. Si-NEC and Co-NEC were associated with 27 and 12 hippocampal differentially expressed genes (DEGs), respectively. These included genes related to neuroinflammation (i.e., S100A8, S100A9, IL8, IL6, MMP8, SAA, TAGLN2) and hypoxia (i.e., PDK4, IER3, TXNIP, AGER), and they were all upregulated in Si-NEC pigs. Genes related to protection against oxidative stress (HBB, ALAS2) and oligodendrocytes (OPALIN) were downregulated in Si-NEC pigs. CSF collected from NEC pigs promoted neurite outgrowth in vitro, and the S100A9 and S100A8/S100A9 proteins may mediate the neuritogenic effects of NEC-related CSF on hippocampal neurons. NEC lesions did not affect total microglial cell number but markedly increased the proportion of Iba1-positive amoeboid microglial cells. Conclusions NEC lesions, especially when present in the small intestine, are associated with changes to hippocampal gene expression that potentially mediate neuroinflammation and disturbed neural circuit formation via enhanced neuronal differentiation. Early brain-protective interventions may be critical for preterm infants affected by intestinal NEC lesions to reduce their later neurological dysfunctions. Electronic supplementary material The online version of this article (10.1186/s12974-018-1201-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jing Sun
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Xiaoyu Pan
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Line I Christiansen
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Xiao-Long Yuan
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Kerstin Skovgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Dereck E W Chatterton
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark.,Department of Food Science, University of Copenhagen, DK-1958, Frederiksberg C, Denmark
| | - Sanne S Kaalund
- Research Laboratory for Stereology and Neuroscience, Bispebjerg-Frederiksberg Hospitals, DK-2400, Copenhagen, Denmark
| | - Fei Gao
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, 518000, Shenzhen, China
| | - Per T Sangild
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark. .,Department of Pediatrics and Adolescent Medicine, Rigshospitalet, Blegdamsvej 9, DK-2100, Copenhagen, Denmark.
| | - Stanislava Pankratova
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, Blegdamsvej 9, DK-2100, Copenhagen, Denmark. .,Laboratory of Neural Plasticity, Department of Neuroscience, University of Copenhagen, DK-2200, Copenhagen, Denmark.
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11
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Gaspar NK, Aidé MK. Atopic dermatitis: allergic dermatitis or neuroimmune dermatitis? An Bras Dermatol 2016; 91:479-88. [PMID: 27579744 PMCID: PMC4999107 DOI: 10.1590/abd1806-4841.20164211] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 04/16/2015] [Indexed: 05/05/2023] Open
Abstract
Advances in knowledge of neurocellulars relations have provided new directions in the understanding and treatment of numerous conditions, including atopic dermatitis. It is known that emotional, physical, chemical or biological stimuli can generate more accentuated responses in atopic patients than in non-atopic individuals; however, the complex network of control covered by these influences, especially by neuropeptides and neurotrophins, and their genetic relations, still keep secrets to be revealed. Itching and airway hyperresponsiveness, the main aspects of atopy, are associated with disruption of the neurosensory network activity. Increased epidermal innervation and production of neurotrophins, neuropeptides, cytokines and proteases, in addition to their relations with the sensory receptors in an epidermis with poor lipid mantle, are the aspects currently covered for understanding atopic dermatitis.
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12
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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: 20.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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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: 12.6] [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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Abstract
Chronic itch is a debilitating condition that affects one in 10 people. Little is known about the molecules that mediate chronic itch in primary sensory neurons and skin. We demonstrate that the ion channel TRPA1 is required for chronic itch. Using a mouse model of chronic itch, we show that scratching evoked by impaired skin barrier is abolished in TRPA1-deficient animals. This model recapitulates many of the pathophysiological hallmarks of chronic itch that are observed in prevalent human diseases such as atopic dermatitis and psoriasis, including robust scratching, extensive epidermal hyperplasia, and dramatic changes in gene expression in sensory neurons and skin. Remarkably, TRPA1 is required for both transduction of chronic itch signals to the CNS and for the dramatic skin changes triggered by dry-skin-evoked itch and scratching. These data suggest that TRPA1 regulates both itch transduction and pathophysiological changes in the skin that promote chronic itch.
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