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Reis MDDS, Veneziani LP, Porto FL, Lins MP, Mendes-da-Cruz DA, Savino W. Intrathymic somatotropic circuitry: consequences upon thymus involution. Front Immunol 2023; 14:1108630. [PMID: 37426675 PMCID: PMC10323194 DOI: 10.3389/fimmu.2023.1108630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 06/05/2023] [Indexed: 07/11/2023] Open
Abstract
Growth hormone (GH) is a classic pituitary-derived hormone crucial to body growth and metabolism. In the pituitary gland, GH production is stimulated by GH-releasing hormone and inhibited by somatostatin. GH secretion can also be induced by other peptides, such as ghrelin, which interacts with receptors present in somatotropic cells. It is well established that GH acts directly on target cells or indirectly by stimulating the production of insulin-like growth factors (IGFs), particularly IGF-1. Notably, such somatotropic circuitry is also involved in the development and function of immune cells and organs, including the thymus. Interestingly, GH, IGF-1, ghrelin, and somatostatin are expressed in the thymus in the lymphoid and microenvironmental compartments, where they stimulate the secretion of soluble factors and extracellular matrix molecules involved in the general process of intrathymic T-cell development. Clinical trials in which GH was used to treat immunocompromised patients successfully recovered thymic function. Additionally, there is evidence that the reduction in the function of the somatotropic axis is associated with age-related thymus atrophy. Treatment with GH, IGF-1 or ghrelin can restore thymopoiesis of old animals, thus in keeping with a clinical study showing that treatment with GH, associated with metformin and dehydroepiandrosterone, could induce thymus regeneration in healthy aged individuals. In conclusion, the molecules of the somatotrophic axis can be envisioned as potential therapeutic targets for thymus regeneration in age-related or pathological thymus involution.
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Affiliation(s)
- Maria Danielma dos Santos Reis
- Laboratory of Cell Biology, Institute of Biological and Health Sciences, Federal University of Alagoas, Maceió, Brazil
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
| | - Luciana Peixoto Veneziani
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- INOVA-IOC Network on Neuroimmunomodulation, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Felipe Lima Porto
- Laboratory of Cell Biology, Institute of Biological and Health Sciences, Federal University of Alagoas, Maceió, Brazil
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
| | - Marvin Paulo Lins
- Laboratory of Cell Biology, Institute of Biological and Health Sciences, Federal University of Alagoas, Maceió, Brazil
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
| | - Daniella Arêas Mendes-da-Cruz
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- INOVA-IOC Network on Neuroimmunomodulation, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Wilson Savino
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Rio de Janeiro Research Network on Neuroinflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- INOVA-IOC Network on Neuroimmunomodulation, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
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Francelin C, Veneziani LP, Farias ADS, Mendes-da-Cruz DA, Savino W. Neurotransmitters Modulate Intrathymic T-cell Development. Front Cell Dev Biol 2021; 9:668067. [PMID: 33928093 PMCID: PMC8076891 DOI: 10.3389/fcell.2021.668067] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 03/25/2021] [Indexed: 11/13/2022] Open
Abstract
The existence of a crosstalk between the nervous and immune systems is well established. Neurotransmitters can be produced by immune cells, whereas cytokines can be secreted by cells of nervous tissues. Additionally, cells of both systems express the corresponding receptors. Herein, we discuss the thymus as a paradigm for studies on the neuroimmune network. The thymus is a primary lymphoid organ responsible for the maturation of T lymphocytes. Intrathymic T-cell development is mostly controlled by the thymic microenvironment, formed by thymic epithelial cells (TEC), dendritic cells, macrophages, and fibroblasts. Developing thymocytes and microenvironmental cells can be influenced by exogenous and endogenous stimuli; neurotransmitters are among the endogenous molecules. Norepinephrine is secreted at nerve endings in the thymus, but are also produced by thymic cells, being involved in controlling thymocyte death. Thymocytes and TEC express acetylcholine receptors, but the cognate neurotransmitter seems to be produced and released by lymphoid and microenvironmental cells, not by nerve endings. Evidence indicates that, among others, TECs also produce serotonin and dopamine, as well as somatostatin, substance P, vasoactive intestinal peptide (VIP) and the typical pituitary neurohormones, oxytocin and arg-vasopressin. Although functional data of these molecules in the thymus are scarce, they are likely involved in intrathymic T cell development, as exemplified by somatostatin, which inhibits thymocyte proliferation, differentiation, migration and cytokine production. Overall, intrathymic neuroimmune interactions include various neurotransmitters, most of them of non-neuronal origin, and that should be placed as further physiological players in the general process of T-cell development.
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Affiliation(s)
- Carolina Francelin
- Autoimmune Research Laboratory, Department of Genetics, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,Department of Ophthalmology and Visual Sciences, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Luciana Peixoto Veneziani
- National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,Laboratory on Thymus Research, Oswaldo Cruz Foundation, Oswaldo Cruz Institute, Rio de Janeiro, Brazil.,Rio de Janeiro Research Network on Neuroinflammation (RENEURIN), Rio de Janeiro, Brazil
| | - Alessandro Dos Santos Farias
- Autoimmune Research Laboratory, Department of Genetics, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Daniella Arêas Mendes-da-Cruz
- National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Wilson Savino
- National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.,National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
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3
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RNA-Seq-Based Gene Expression Pattern and Morphological Alterations in Chick Thymus during Postnatal Development. Int J Genomics 2019; 2019:6905194. [PMID: 31179312 PMCID: PMC6501151 DOI: 10.1155/2019/6905194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 12/20/2018] [Accepted: 02/25/2019] [Indexed: 12/23/2022] Open
Abstract
The thymus is a lobulated unique lymphoid immune organ that plays a critical role in the selection, development, proliferation, and differentiation of T cells. The thymus of developing chickens undergoes continued morphological alterations; however, the biomolecular and transcriptional dynamics of the postnatal thymus in avian species is not clear yet. Therefore, the thymuses from chickens at different stages of development (at weeks 0, 1, 5, 9, 18, and 27) were used in the present study. The RNA-seq method was used to study the gene expression patterns. On average, 24120819 clean reads were mapped, differentially expressed genes (DEGs) were identified on the basis of log values (fold change), including 744 upregulated and 425 downregulated genes. The expression pattern revealed by RNA-seq was validated by quantitative real-time PCR (qPCR) analysis of four important genes, which are PCNA, CCNA2, CCNB2, and CDK1. Thus, the current study revealed that during postnatal development, the thymus undergoes severe atrophy. Thymus structure was damaged and gene expression changed dramatically, especially at the 27th week of age. Moreover, we found significant changes of several signaling pathways such as the cytokine-cytokine receptor interaction and cell cycle signaling pathways. Hence, it may be inferred that those signaling pathways might be closely related to the postnatal chicken thymus development.
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Paltsev MA, Polyakova VO, Kvetnoy IM, Anderson G, Kvetnaia TV, Linkova NS, Paltseva EM, Rubino R, De Cosmo S, De Cata A, Mazzoccoli G. Morphofunctional and signaling molecules overlap of the pineal gland and thymus: role and significance in aging. Oncotarget 2017; 7:11972-83. [PMID: 26943046 PMCID: PMC4914262 DOI: 10.18632/oncotarget.7863] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 02/23/2016] [Indexed: 12/02/2022] Open
Abstract
Deficits in neuroendocrine-immune system functioning, including alterations in pineal and thymic glands, contribute to aging-associated diseases. This study looks at ageing-associated alterations in pineal and thymic gland functioning evaluating common signaling molecules present in both human and animal pinealocytes and thymocytes: endocrine cell markers (melatonin, serotonin, pCREB, AANAT, CGRP, VIP, chromogranin A); cell renovation markers (p53, AIF, Ki67), matrix metalloproteinases (MMP2, MMP9) and lymphocytes markers (CD4, CD5, CD8, CD20). Pineal melatonin is decreased, as is one of the melatonin pathway synthesis enzymes in the thymic gland. A further similarity is the increased MMPs levels evident over age in both glands. Significant differences are evident in cell renovation processes, which deteriorate more quickly in the aged thymus versus the pineal gland. Decreases in the number of pineal B-cells and thymic T-cells were also observed over aging. Collected data indicate that cellular involution of the pineal gland and thymus show many commonalities, but also significant changes in aging-associated proteins. It is proposed that such ageing-associated alterations in these two glands provide novel pharmaceutical targets for the wide array of medical conditions that are more likely to emerge over the course of ageing.
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Affiliation(s)
| | - Victoria O Polyakova
- Department of Pathology, Ott Institute of Obstetrics, Gynecology and Reproductology, St. Petersburg, Russian Federation, Russia.,Laboratory of Cell Biology and Pathology, Institute of Bioregulation and Gerontology, St. Petersburg, Russian Federation, Russia
| | - Igor M Kvetnoy
- Department of Pathology, Ott Institute of Obstetrics, Gynecology and Reproductology, St. Petersburg, Russian Federation, Russia.,Laboratory of Cell Biology and Pathology, Institute of Bioregulation and Gerontology, St. Petersburg, Russian Federation, Russia
| | | | - Tatiana V Kvetnaia
- Department of Pathology, Ott Institute of Obstetrics, Gynecology and Reproductology, St. Petersburg, Russian Federation, Russia
| | - Natalia S Linkova
- Department of Pathology, Ott Institute of Obstetrics, Gynecology and Reproductology, St. Petersburg, Russian Federation, Russia
| | - Ekaterina M Paltseva
- Division of Immuhistochemistry, B.V. Petrovsky Russian Surgery Research Center, Moscow, Russian Federation, Russia
| | - Rosa Rubino
- Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS Scientific Institute and Regional General Hospital "Casa Sollievo della Sofferenza", Opera di Padre Pio da Pietrelcina, San Giovanni Rotondo (FG), Italy
| | - Salvatore De Cosmo
- Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS Scientific Institute and Regional General Hospital "Casa Sollievo della Sofferenza", Opera di Padre Pio da Pietrelcina, San Giovanni Rotondo (FG), Italy
| | - Angelo De Cata
- Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS Scientific Institute and Regional General Hospital "Casa Sollievo della Sofferenza", Opera di Padre Pio da Pietrelcina, San Giovanni Rotondo (FG), Italy
| | - Gianluigi Mazzoccoli
- Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS Scientific Institute and Regional General Hospital "Casa Sollievo della Sofferenza", Opera di Padre Pio da Pietrelcina, San Giovanni Rotondo (FG), Italy
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5
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Franchini A, Ottaviani E. Thymus: Conservation in evolution. Gen Comp Endocrinol 2017; 246:46-50. [PMID: 28322763 DOI: 10.1016/j.ygcen.2017.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/16/2017] [Accepted: 03/16/2017] [Indexed: 11/17/2022]
Abstract
From an evolutionary point of view, the thymus is a new organ observed for the first time in fish concomitantly with the appearance of adaptive clonotypical immunity. Hormone and neuropeptide expression was demonstrated in different species suggesting a conserved role of these molecules. An integrated evolution of immune and neuroendocrine responses appears to have been realized by means of the re-use of ancestral material, such as neuroendocrine cells and mediators, to create a thymic microenvironment for the maturation and differentiation of T cells.
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Affiliation(s)
- Antonella Franchini
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Enzo Ottaviani
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy.
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6
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Hanyang L, Xuanzhe L, Xuyang C, Yujia Q, Jiarong F, Jun S, Zhihua R. Application of Zebrafish Models in Inflammatory Bowel Disease. Front Immunol 2017; 8:501. [PMID: 28515725 PMCID: PMC5413514 DOI: 10.3389/fimmu.2017.00501] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/11/2017] [Indexed: 12/12/2022] Open
Abstract
Inflammatory bowel disease (IBD) is a chronic, recurrent, and remitting inflammatory disease with unclear etiology. As a clinically frequent disease, it can affect individuals throughout their lives, with multiple complications. Unfortunately, traditional murine models are not efficient for the further study of IBD. Thus, effective and convenient animal models are needed. Zebrafish have been used as model organisms to investigate IBD because of their suggested highly genetic similarity to humans and their superiority as laboratory models. The zebrafish model has been used to study the composition of intestinal microbiota, novel genes, and therapeutic approaches. The pathogenesis of IBD is still unclear and many risk factors remain unidentified. In this review, we compare traditional murine models and zebrafish models in terms of advantages, pathogenesis, and drug discovery screening for IBD. We also review the progress and deficiencies of the zebrafish model for scientific applications.
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Affiliation(s)
- Li Hanyang
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai, China.,Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Shanghai Institute of Digestive Disease, Shanghai, China
| | - Liu Xuanzhe
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai, China.,Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Shanghai Institute of Digestive Disease, Shanghai, China
| | - Chen Xuyang
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai, China.,Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Shanghai Institute of Digestive Disease, Shanghai, China
| | - Qiu Yujia
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai, China.,Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Shanghai Institute of Digestive Disease, Shanghai, China
| | - Fu Jiarong
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai, China.,Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Shanghai Institute of Digestive Disease, Shanghai, China
| | - Shen Jun
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai, China.,Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Shanghai Institute of Digestive Disease, Shanghai, China
| | - Ran Zhihua
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Shanghai, China.,Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Shanghai Institute of Digestive Disease, Shanghai, China
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7
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The effects of aging and maternal protein restriction during lactation on thymic involution and peripheral immunosenescence in adult mice. Oncotarget 2016; 7:6398-409. [PMID: 26843625 PMCID: PMC4872722 DOI: 10.18632/oncotarget.7176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 01/25/2016] [Indexed: 12/02/2022] Open
Abstract
Environmental factors such as nutrition during early life can influence long-term health, a concept termed developmental programming. Initial research was focused towards the effects on metabolic health but more recent studies have demonstrated effects on parameters such as lifespan and immunity. In this study we report that maternal protein restriction during lactation in mice, that is known to prolong lifespan, slows aging of the central and peripheral immune systems. Offspring of dams fed a postnatal low-protein (PLP) diet during lactation had a significant increase in thymic cellularity and T cell numbers across their lifespan compared to controls, and a less marked age-associated decrease in thymocyte cluster of differentiation (CD) 3 expression. PLP animals also demonstrated increased relative splenic cellularity, increased naïve: memory CD4+ and CD8+ T cell ratios, increased staining and density of germinal centres, and decreased gene expression of p16 in the spleen, a robust biomarker of aging. A slower rate of splenic aging in PLP animals would be expected to result in decreased susceptibility to infection and neoplasia. In conclusion nutritionally-induced slow postnatal growth leads to delayed aging of the adaptive immune system, which may contribute towards the extended lifespan observed in these animals.
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Thymic Structures Containing Somatostatin. Bull Exp Biol Med 2015. [PMID: 26205725 DOI: 10.1007/s10517-015-2970-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Double immunofluorescent staining confirmed co-expression of somatostatin (neuropeptide) and antigen-presenting cells of macrophage origin expressing major histocompatibility complex class II molecules in the intact thymus. The results confirmed cooperation of the neuropeptide and immunocompetent systems.
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9
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Min C, Min H, Kemei P, Ke X, Haibo H, Daiyun Z, Xinting Z. Expression of somatostatin and cDNA cloning in the thymus of the African ostrich. Acta Histochem 2014; 116:191-6. [PMID: 23915476 DOI: 10.1016/j.acthis.2013.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 06/30/2013] [Accepted: 07/02/2013] [Indexed: 11/15/2022]
Abstract
The thymus in addition to being a central lymphoid organ is also an endocrine organ which produces various neuropeptides that influence the function of this gland. Somatostatin is a neuropeptide that was isolated initially in the hypothalamus and which inhibits the release of growth hormone. The distribution of somatostatin-producing cells and the sequence of somatostatin have been determined in many species. In the present study, we investigated the expression of somatostatin in the thymus of the African ostrich and its sequence by reverse-transcriptase polymerase chain reaction and immunohistochemistry. The results showed that somatostatin mRNA was expressed in the thymus and somatostatin immunoreative cells were distributed in both the cortical and medullary regions of the thymus. Results of cDNA cloning revealed that the nucleotide sequence and the encoded protein of African ostrich somatostatin were 348 bases and 116 amino acids in length and that it is highly conserved to that of other reported species. These findings indicated that the somatostatin expressed in the thymus of ostrich might play an important role in the function of the gland. In addition, this research has provided novel molecular data allowing further study of somatostatin in the ostrich.
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Affiliation(s)
- Chen Min
- College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China; Xinyang College of Agriculture and Forestry, Xinyang 464000, Henan, PR China.
| | - He Min
- Xinyang College of Agriculture and Forestry, Xinyang 464000, Henan, PR China
| | - Peng Kemei
- College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.
| | - Xiao Ke
- College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China
| | - Huang Haibo
- College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China
| | - Zhu Daiyun
- College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China
| | - Zheng Xinting
- College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China
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10
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Geiger BM, Gras-Miralles B, Ziogas DC, Karagiannis AKA, Zhen A, Fraenkel P, Kokkotou E. Intestinal upregulation of melanin-concentrating hormone in TNBS-induced enterocolitis in adult zebrafish. PLoS One 2013; 8:e83194. [PMID: 24376661 PMCID: PMC3869761 DOI: 10.1371/journal.pone.0083194] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 11/11/2013] [Indexed: 12/22/2022] Open
Abstract
Background Melanin-concentrating hormone (MCH), an evolutionarily conserved appetite-regulating neuropeptide, has been recently implicated in the pathogenesis of inflammatory bowel disease (IBD). Expression of MCH is upregulated in inflamed intestinal mucosa in humans with colitis and MCH-deficient mice treated with trinitrobenzene-sulfonic acid (TNBS) develop an attenuated form of colitis compared to wild type animals. Zebrafish have emerged as a new animal model of IBD, although the majority of the reported studies concern zebrafish larvae. Regulation MCH expression in the adult zebrafish intestine remains unknown. Methods In the present study we induced enterocolitis in adult zebrafish by intrarectal administration of TNBS. Follow-up included survival analysis, histological assessment of changes in intestinal architecture, and assessment of intestinal infiltration by myeloperoxidase positive cells and cytokine transcript levels. Results Treatment with TNBS dose-dependently reduced fish survival. This response required the presence of an intact microbiome, since fish pre-treated with vancomycin developed less severe enterocolitis. At 6 hours post-challenge, we detected a significant influx of myeloperoxidase positive cells in the intestine and upregulation of both proinflammatory and anti-inflammatory cytokines. Most importantly, and in analogy to human IBD and TNBS-induced mouse experimental colitis, we found increased intestinal expression of MCH and its receptor in TNBS-treated zebrafish. Conclusions Taken together these findings not only establish a model of chemically-induced experimental enterocolitis in adult zebrafish, but point to effects of MCH in intestinal inflammation that are conserved across species.
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Affiliation(s)
- Brenda M Geiger
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Beatriz Gras-Miralles
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Dimitrios C Ziogas
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Apostolos K A Karagiannis
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Aileen Zhen
- Hematology/Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Paula Fraenkel
- Hematology/Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Efi Kokkotou
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America
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11
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Hirsch D, Zukowska Z. NPY and stress 30 years later: the peripheral view. Cell Mol Neurobiol 2012; 32:645-59. [PMID: 22271177 DOI: 10.1007/s10571-011-9793-z] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 12/26/2011] [Indexed: 02/06/2023]
Abstract
Almost 30 years ago, neuropeptide Y (NPY) was discovered as a sympathetic co-transmitter and one of the most evolutionarily conserved peptides abundantly present all over the body. Soon afterward, NPY's multiple receptors were characterized and cloned, and the peptide's role in stress was first documented. NPY has proven to be pivotal for maintaining many stress responses. Most notably, NPY is known for activating long-lasting vasoconstriction in many vascular beds, including coronary arteries. More recently, NPY was found to play a role in stress-induced accretion of adipose tissue which many times can lead to detrimental metabolic changes. It is however due to its prominent actions in the brain, one of which is its powerful ability to stimulate appetite as well as its anxiolytic activities that NPY became a peptide of importance in neuroscience. In contrast, its actions in the rest of the body, including its role as a stress mediator, remained, surprisingly underappreciated and not well understood. Our research has focused on that other, "peripheral" side of NPY. In this review, we will discuss those actions of NPY on the cardiovascular system and metabolism, as they relate to adaptation to stress, and attempt to both distinguish NPY's effects from and integrate them with the effects of the classical stress mediators, glucocorticoids, and catecholamines. To limit the bias of someone (ZZ) who has viewed the world of stress through the eyes of NPY for over 20 years, fresh insight (DH) has been solicited to more objectively assess NPY's contributions to stress-related diseases and the body's ability to adapt to stress.
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Affiliation(s)
- Dalay Hirsch
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, MN 55455, USA.
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Vigliano FA, Losada AP, Castello M, Bermúdez R, Quiroga MI. Morphological and immunohistochemical characterisation of the thymus in juvenile turbot (Psetta maxima, L.). Cell Tissue Res 2011; 346:407-16. [DOI: 10.1007/s00441-011-1282-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 10/24/2011] [Indexed: 11/30/2022]
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Leposavić G, Pilipović I, Perišić M. Cellular and nerve fibre catecholaminergic thymic network: steroid hormone dependent activity. Physiol Res 2011; 60:S71-82. [PMID: 21777027 DOI: 10.33549/physiolres.932175] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The thymus plays a critical role in establishing and maintaining the peripheral T-cell pool. It does so by providing a microenvironment within which T-cell precursors differentiate and undergo selection processes to create a functional population of major histocompatibility complex-restricted, self-tolerant T cells. These cells are central to adaptive immunity. Thymic T-cell development is influenced by locally produced soluble factors and cell-to-cell interactions, as well as by sympathetic noradrenergic and endocrine system signalling. Thymic lymphoid and non-lymphoid cells have been shown not only to express beta- and alpha(1)- adrenoceptors (ARs), but also to synthesize catecholamines (CAs). Thus, it is suggested that CAs influence T-cell development via both neurocrine/endocrine and autocrine/paracrine action, and that they serve as immunotransmitters between thymocytes and nerves. CAs acting at multiple sites along the thymocyte developmental route affect T-cell generation not only numerically, but also qualitatively. Thymic CA level and synthesis, as well as AR expression exhibit sex steroid-mediated sexual dimorphism. Moreover, the influence of CAs on T-cell development exhibits glucocorticoid-dependent plasticity. This review summarizes recent findings in this field and our current understanding of complex and multifaceted neuroendocrine-immune communications at thymic level.
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Affiliation(s)
- G Leposavić
- Immunology Research Centre Branislav Janković, Institute of Virology, Vaccines and Sera Torlak, Belgrade, Serbia.
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14
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Huang J, Stohl LL, Zhou X, Ding W, Granstein RD. Calcitonin gene-related peptide inhibits chemokine production by human dermal microvascular endothelial cells. Brain Behav Immun 2011; 25:787-99. [PMID: 21334428 PMCID: PMC3081395 DOI: 10.1016/j.bbi.2011.02.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 02/09/2011] [Accepted: 02/14/2011] [Indexed: 02/08/2023] Open
Abstract
This study examined whether the sensory neuropeptide calcitonin gene-related peptide (CGRP) inhibits release of chemokines by dermal microvascular endothelial cells. Dermal blood vessels are associated with nerves containing CGRP, suggesting that CGRP-containing nerves may regulate cutaneous inflammation through effects on vessels. We examined CGRP effects on stimulated chemokine production by a human dermal microvascular endothelial cell line (HMEC-1) and primary human dermal microvascular endothelial cells (pHDMECs). HMEC-1 cells and pHDMECs expressed mRNA for components of the CGRP and adrenomedullin receptors and CGRP inhibited LPS-induced production of the chemokines CXCL8, CCL2, and CXCL1 by both HMEC-1 cells and pHDMECs. The receptor activity-modifying protein (RAMP)1/calcitonin receptor-like receptor (CL)-specific antagonists CGRP₈-₃₇ and BIBN4096BS, blocked this effect of CGRP in a dose-dependent manner. CGRP prevented LPS-induced IκBα degradation and NF-κB binding to the promoters of CXCL1, CXCL8 and CCL2 in HMEC-1 cells and Bay 11-7085, an inhibitor of NF-κB activation, suppressed LPS-induced production of CXCL1, CXCL8 and CCL2. Thus, the NF-κB pathway appears to be involved in CGRP-mediated suppression of chemokine production. Accordingly, CGRP treatment of LPS-stimulated HMEC-1 cells inhibited their ability to chemoattract human neutrophils and mononuclear cells. Elucidation of this pathway may suggest new avenues for therapeutic manipulation of cutaneous inflammation.
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Affiliation(s)
- Jing Huang
- Department of Dermatology, Weill Cornell Medical College, New York, New York, 10021 USA
| | - Lori L. Stohl
- Department of Dermatology, Weill Cornell Medical College, New York, New York, 10021 USA
| | - Xi Zhou
- Department of Public Health, Weill Cornell Medical College, New York, New York, 10021 USA
| | - Wanhong Ding
- Department of Dermatology, Weill Cornell Medical College, New York, New York, 10021 USA
| | - Richard D. Granstein
- Department of Dermatology, Weill Cornell Medical College, New York, New York, 10021 USA
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15
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Silva AB, Palmer DB. Evidence of conserved neuroendocrine interactions in the thymus: intrathymic expression of neuropeptides in mammalian and non-mammalian vertebrates. Neuroimmunomodulation 2011; 18:264-70. [PMID: 21952678 DOI: 10.1159/000329493] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The function of lymphoid organs and immune cells is often modulated by hormones, steroids and neuropeptides produced by the neuroendocrine and immune systems. The thymus intrinsically produces these factors and a comparative analysis of the expression of neuropeptides in the thymus of different species would highlight the evolutionary importance of neuroendocrine interaction in T cell development. In this review, we highlight the evidence which describes the intrathymic expression and function of various neuropeptides and their receptors, in particular somatostatin, substance P, vasointestinal polypeptide, calcitonin gene-related peptide and neuropeptide Y, in mammals (human, rodent) and non-mammals (avian, amphibian and teleost), and conclude that neuropeptides play a conserved role in vertebrate thymocyte development.
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Affiliation(s)
- Alberto B Silva
- Infection and Immunity Group, Department of Veterinary Basic Sciences, Royal Veterinary College, London, UK
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16
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Zhang X, Zhu J, Loh YP, Berghman LR. Carboxypeptidase E, an essential element of the regulated secretory pathway, is expressed and partially co-localized with chromogranin A in chicken thymus. Cell Tissue Res 2009; 337:371-9. [PMID: 19603184 DOI: 10.1007/s00441-009-0830-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2009] [Accepted: 06/18/2009] [Indexed: 01/28/2023]
Abstract
Although the functions of hormones and neuropeptides in the thymus have been extensively studied, we still do not know whether these intra-thymic humoral elements are released in a stimulated manner via the regulated secretory pathway or in a constitutive manner. Carboxypeptidase E (CpE) and chromogranin A (CgA) are functional and structural hallmarks of the regulated secretory pathway in (neuro)endocrine cells. Whereas we have previously shown a CgA-positive neuroendocrine population in the chicken thymus, the current study assesses the expression of CpE in the thymus, both at the mRNA and the protein level. Our immunohistochemical studies provide evidence for the co-existence of CgA and CpE in identical neuroendocrine cells in the thymus. CpE and CgA dual-positive cells have primarily been found in the transition zone between the cortex and medulla of the thymus, an area known to contain numerous arterioles and to be innervated by the autonomic nervous system. Our findings suggest that the diffuse neuroendocrine system serves as a relay for nervous stimuli delivered by the sympathetic and/or parasympathetic nervous system. Thus, these newly defined neuroendocrine cells might play an important role in the immuno-neuro-endocrine cross-talk in the thymus, potentially enabling thymopoiesis to be fine-tuned via the regulated secretory pathway by a variety of physical and environmental factors.
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Affiliation(s)
- Xiaodong Zhang
- Department of Poultry Science, Texas A&M University, College Station, TX 77843, USA
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17
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Patel K, Taub DD. Role of neuropeptides, hormones, and growth factors in regulating thymopoiesis in middle to old age. F1000 BIOLOGY REPORTS 2009; 1:42. [PMID: 20948643 PMCID: PMC2924688 DOI: 10.3410/b1-42] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The deterioration in adaptive immunity and T-lymphocyte output and the narrowing of the T cell receptor repertoire with age are largely attributable to thymic involution. The loss of thymic function with age may be due to diminished numbers of early thymic progenitors and epithelial cells, and the loss of critical tropic factors within the thymic microenvironment. Here we review some of the recent literature demonstrating a role for neuropeptides, hormones, and growth factors that can influence thymopoiesis associated with stress and aging.
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Affiliation(s)
- Kalpesh Patel
- Laboratory of Immunology, National Institute of Aging, Intramural Research Program, National Institutes of Health, Biomedical Research Center 251 Bayview Boulevard, Room 8C222, Baltimore, MD 21224 USA
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18
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Mendes-da-Cruz DA, Lepelletier Y, Brignier AC, Smaniotto S, Renand A, Milpied P, Dardenne M, Hermine O, Savino W. Neuropilins, semaphorins, and their role in thymocyte development. Ann N Y Acad Sci 2009; 1153:20-8. [PMID: 19236324 DOI: 10.1111/j.1749-6632.2008.03980.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Some molecules described in the nervous system are also expressed in cells involved in the control of the immune response, suggesting they have a role as common mechanisms between neuroendocrine and immune systems. In this review, we focus on the expression and role of neuropilins (NPs) and their soluble ligands class 3 semaphorins in thymus physiology, particularly migration of developing thymocytes. We also discuss the concept of multivectorial thymocyte migration, including semaphorins, as a new individual cell migration vector.
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19
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Pollak DD, Monje FJ, Zuckerman L, Denny CA, Drew MR, Kandel ER. An animal model of a behavioral intervention for depression. Neuron 2008; 60:149-61. [PMID: 18940595 PMCID: PMC3417703 DOI: 10.1016/j.neuron.2008.07.041] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 08/26/2008] [Accepted: 07/30/2008] [Indexed: 11/25/2022]
Abstract
Although conditioned inhibition of fear (or learned safety) is a learning process critical for preventing chronic stress, a predisposing factor for depression and other psychopathologies, little is known about its functional purposes or molecular mechanisms. To obtain better insight into learned safety, we investigated its behavioral and molecular characteristics and found that it acts as a behavioral antidepressant in two animal models. Learned safety promotes the survival of newborn cells in the dentate gyrus of the hippocampus, while its antidepressant effect is abolished in mice with ablated hippocampal neurogenesis. Learned safety also increases the expression of BDNF in the hippocampus and leads to downregulation of genes involved in the dopaminergic and neuropeptidergic but not the serotonergic system in the basolateral amygdala. These data suggest that learned safety is an animal model of a behavioral antidepressant that shares some neuronal hallmarks of pharmacological antidepressants but is mediated by different molecular pathways.
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Affiliation(s)
- Daniela D Pollak
- Department of Neuroscience, Columbia University, 1051 Riverside Drive, New York, NY 10032, USA
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20
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Phenotypical and morphological changes in the thymic microenvironment from ageing mice. Biogerontology 2008; 10:311-22. [PMID: 18931936 DOI: 10.1007/s10522-008-9182-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Accepted: 09/25/2008] [Indexed: 10/21/2022]
Abstract
The thymus is crucial for T-cell output and the age-associated involution of this organ, is thought to have a major impact in the decline in immunity that is seen in later life. The mechanism that underlines thymic involution is not known, however, we have evidence to suggest that this is may be due to changes in the thymic microenvironment. To further test this hypothesis, we quantified the in situ changes to markers that identify cortical and medullary thymic epithelial cells. This analysis revealed an age-dependent decline in cortical and medullary markers together with an increase in Notch and Delta expression, in older mice, as judged by immunohistochemistry. This was accompanied by alterations of the archetypal staining patterns and three dimensional analysis revealed changes in the morphology of the thymic microenvironment. These studies suggest that there are age-associated alterations in the thymic microenvironment, which may therefore play a role in thymic involution.
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21
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Abstract
Age-associated thymic involution is one of the most dramatic and ubiquitous changes in the immune system, although the precise mechanisms involved still remain obscured. Several hypotheses have been proposed incorporating extrinsic and intrinsic factors, however, changes in the thymic microenvironment itself is one of the least investigated. We therefore decided to undertake a detailed histological examination of the aging thymus in order to elucidate possible mechanisms of thymic atrophy. This investigation provides insight into the changes within the murine thymus with age, demonstrating a new approach to quantify protein expressional differences while preserving the thymic architecture. There is a decline in expression of thymic epithelial cell-specific makers and an increase in fibroblast content in the aging mouse thymus. This is concurrent with a disorganization of the thymic compartments, a morphological transformation within the epithelial cells and alterations of their archetypal staining patterns. Furthermore, this is linked to a rise in apoptotic cells and the novel finding of increased senescence in the thymus of older mice that appears to be colocalized in the epithelial compartment. These changes within the thymic epithelial cells may be in part accountable for thymic atrophy and responsible for the decline in T-cell output.
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Affiliation(s)
- Danielle Aw
- Host Response and Genes and Development Group, Department of Veterinary Basic Sciences, Royal Veterinary College, Royal College Street, London NW1 0TU, UK
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22
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Silva AB, Aw D, Palmer DB. Functional analysis of neuropeptides in avian thymocyte development. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2008; 32:410-20. [PMID: 17892898 DOI: 10.1016/j.dci.2007.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2007] [Revised: 07/09/2007] [Accepted: 08/01/2007] [Indexed: 05/17/2023]
Abstract
The function of lymphoid organs and immune cells is often modulated by peptides and hormones produced by the neuroendocrine and immune systems. We have previously reported the intrathymic expression of neuropeptides in the thymus of different species and that neuropeptides can influence murine thymocyte development in vitro. To further explore the evolutionary nature of neuroendocrine interactions in the thymus, we identified the expression of calcitonin-gene-related peptide, neuropeptide Y, somatostatin (SOM), substance P and vasointestinal polypeptide, as well as their receptors on chicken thymic epithelial cells (TEC) and thymocytes by immunofluorescence and reverse transcription polymerase chain reaction (RT-PCR). All the studied neuropeptides and their receptors were found to be expressed in both TEC and thymocytes, suggesting that intrathymic neuroendocrine interactions may take place within the avian thymus. In order to elucidate whether such interactions play a role in avian thymocyte development, neuropeptides and their antagonists were added to embryonic thymus organ cultures and found to influence chicken thymopoiesis. In particular, an antagonist of SOM increased the proportion of double-positive thymocytes, while SOM itself appeared to inhibit the early stages of thymocyte development. Taken together, these data provide further evidence to suggest that neuropeptides play a conserved role in vertebrate thymocyte development.
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Affiliation(s)
- Alberto B Silva
- Host Response and Genes and Development Groups, Department of Veterinary Basic Sciences, Royal Veterinary College, Royal College Street, London NW1 0TU, UK
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23
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Tsui H, Razavi R, Chan Y, Yantha J, Dosch HM. ‘Sensing’ autoimmunity in type 1 diabetes. Trends Mol Med 2007; 13:405-13. [PMID: 17900987 DOI: 10.1016/j.molmed.2007.07.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 07/28/2007] [Accepted: 07/28/2007] [Indexed: 02/08/2023]
Abstract
Type 1 diabetes (T1D) results from autoimmune-mediated loss of insulin-producing beta-cells. Recent findings suggest that the events controlling T1D development are not only immunological, but also neuronal in nature. In the non-obese diabetic (NOD) mouse model of T1D, a mutant sensory neuron channel, TRPV1, initiates chronic, progressive beta-cell stress, inducing islet cell inflammation. This novel mechanism of organ-specific damage requires a permissive, autoimmune-prone host, but ascribes tissue specificity to the local secretory dysfunction of sensory afferent neurons. In NOD mice, normalizing this neuronal function by administration of the neurotransmitter substance P clears islet cell inflammation, reduces insulin resistance and restores normoglycemia. Here, we discuss this neuro-immuno-endocrine model, its implications and the involvement of sensory neurons in other autoimmune disorders. These developments might provide novel neuronal-based therapeutic interventions, particularly in diabetes.
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Affiliation(s)
- Hubert Tsui
- The Hospital for Sick Children, Department of Neuroscience and Mental Health, 555 University Avenue, 10128 Elm Wing Toronto, ON, M5G 1X8, Canada
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Abstract
It is now becoming apparent that the immune system undergoes age-associated alterations, which accumulate to produce a progressive deterioration in the ability to respond to infections and to develop immunity after vaccination, both of which are associated with a higher mortality rate in the elderly. Immunosenescence, defined as the changes in the immune system associated with age, has been gathering interest in the scientific and health-care sectors alike. The rise in its recognition is both pertinent and timely given the increasing average age and the corresponding failure to increase healthy life expectancy. This review attempts to highlight the age-dependent defects in the innate and adaptive immune systems. While discussing the mechanisms that contribute to immunosenescence, with emphasis on the extrinsic factors, particular attention will be focused on thymic involution. Finally, we illuminate potential therapies that could be employed to help us live a longer, fuller and healthier life.
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Affiliation(s)
- Danielle Aw
- Royal Veterinary College, Host Response and Genes and Development Group, Department of Veterinary Basic Sciences, Royal College Street, London, United Kingdom
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