1
|
The promise of the TGF-β superfamily as a therapeutic target for Parkinson's disease. Neurobiol Dis 2022; 171:105805. [PMID: 35764291 DOI: 10.1016/j.nbd.2022.105805] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/20/2022] Open
Abstract
A large body of evidence underscore the regulatory role of TGF-β superfamily in the central nervous system. Components of the TGF-β superfamily modulate key events during embryonic brain development and adult brain tissue injury repair. With respect to Parkinson's disease (PD), TGF-ß signaling pathways are implicated in the differentiation, maintenance and synaptic function of the dopaminergic neurons, as well as in processes related to the activation state of astrocytes and microglia. In vitro and in vivo studies using toxin models, have interrogated on the dopaminotrophic and protective role of the TGF-β superfamily members. The evolution of genetic and animal models of PD that more closely recapitulate the disease condition has made possible the dissection of intracellular pathways in response to TGF-ß treatment. Although the first clinical trials using GDNF did not meet their primary endpoints, substantial work has been carried out to reappraise the TGF-β superfamily's clinical benefit.
Collapse
|
2
|
Li L, Ni L, Heary RF, Elkabes S. Astroglial TLR9 antagonism promotes chemotaxis and alternative activation of macrophages via modulation of astrocyte-derived signals: implications for spinal cord injury. J Neuroinflammation 2020; 17:73. [PMID: 32098620 PMCID: PMC7041103 DOI: 10.1186/s12974-020-01748-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 02/13/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The recruitment of immune system cells into the central nervous system (CNS) has a profound effect on the outcomes of injury and disease. Glia-derived chemoattractants, including chemokines, play a pivotal role in this process. In addition, cytokines and chemokines influence the phenotype of infiltrating immune cells. Depending on the stimuli present in the local milieu, infiltrating macrophages acquire the classically activated M1 or alternatively activated M2 phenotypes. The polarization of macrophages into detrimental M1 versus beneficial M2 phenotypes significantly influences CNS pathophysiology. Earlier studies indicated that a toll-like receptor 9 (TLR9) antagonist modulates astrocyte-derived cytokine and chemokine release. However, it is not known whether these molecular changes affect astrocyte-induced chemotaxis and polarization of macrophages. The present studies were undertaken to address these issues. METHODS The chemotaxis and polarization of mouse peritoneal macrophages by spinal cord astrocytes were evaluated in a Transwell co-culture system. Arrays and ELISA were utilized to quantify chemokines in the conditioned medium (CM) of pure astrocyte cultures. Immunostaining for M1- and M2-specific markers characterized the macrophage phenotype. The percentage of M2 macrophages at the glial scar was determined by stereological approaches in mice sustaining a mid-thoracic spinal cord contusion injury (SCI) and intrathecally treated with oligodeoxynucleotide 2088 (ODN 2088), the TLR9 antagonist. Statistical analyses used two-tailed independent-sample t-test and one-way analysis of variance (ANOVA) followed by Tukey's post hoc test. A p value < 0.05 was considered to be statistically significant. RESULTS ODN 2088-treated astrocytes significantly increased the chemotaxis of peritoneal macrophages via release of chemokine (C-C motif) ligand 1 (CCL1). Vehicle-treated astrocytes polarized macrophages into the M2 phenotype and ODN 2088-treated astrocytes promoted further M2 polarization. Reduced CCL2 and CCL9 release by astrocytes in response to ODN 2088 facilitated the acquisition of the M2 phenotype, suggesting that CCL2 and CCL9 are negative regulators of M2 polarization. The percentage of M2 macrophages at the glial scar was higher in mice sustaining a SCI and receiving ODN 2088 treatment as compared to vehicle-treated injured controls. CONCLUSIONS TLR9 antagonism could create a favorable environment during SCI by supporting M2 macrophage polarization and chemotaxis via modulation of astrocyte-to-macrophage signals.
Collapse
Affiliation(s)
- Lun Li
- Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers, The State University of New Jersey, 205 South Orange Avenue, F-1204, Newark, NJ 07103 USA
| | - Li Ni
- Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers, The State University of New Jersey, 205 South Orange Avenue, F-1204, Newark, NJ 07103 USA
| | - Robert F. Heary
- Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers, The State University of New Jersey, 205 South Orange Avenue, F-1204, Newark, NJ 07103 USA
| | - Stella Elkabes
- Reynolds Family Spine Laboratory, Department of Neurosurgery, New Jersey Medical School, Rutgers, The State University of New Jersey, 205 South Orange Avenue, F-1204, Newark, NJ 07103 USA
| |
Collapse
|
3
|
A Parkinson's disease gene, DJ-1, regulates anti-inflammatory roles of astrocytes through prostaglandin D2 synthase expression. Neurobiol Dis 2019; 127:482-491. [DOI: 10.1016/j.nbd.2019.04.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/07/2019] [Accepted: 04/03/2019] [Indexed: 01/24/2023] Open
|
4
|
De Vita T, Albani C, Realini N, Migliore M, Basit A, Ottonello G, Cavalli A. Inhibition of Serine Palmitoyltransferase by a Small Organic Molecule Promotes Neuronal Survival after Astrocyte Amyloid Beta 1-42 Injury. ACS Chem Neurosci 2019; 10:1627-1635. [PMID: 30481470 DOI: 10.1021/acschemneuro.8b00556] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Alzheimer's disease (AD) is a slow-progressing disease of the brain characterized by symptoms such as impairment of memory and other cognitive functions. AD is associated with an inflammatory process that involves astrocytes and microglial cells, among other components. Astrocytes are the most abundant type of glial cells in the central nervous system (CNS). They are involved in inducing neuroinflammation. The present study uses astrocyte-neuron cocultures to investigate how ARN14494, a serine palmitoyltransferase (SPT) inhibitor, affects the CNS in terms of anti-inflammation and neuroprotection. SPT is the first rate-limiting enzyme in the de novo ceramide synthesis pathway. Consistent evidence suggests that ceramide is increased in AD brain patients. After β-amyloid 1-42 injury in an in vitro model of AD, ARN14494 inhibits SPT activity and the synthesis of long-chain ceramides and dihydroceramides that are involved in AD progression. In mouse primary cortical astrocytes, ARN14494 prevents the synthesis of proinflammatory cytokines TNFα and IL1β, growth factor TGFβ1, and oxidative stress-related enzymes iNOS and COX2. ARN14494 also exerts neuroprotective properties in primary cortical neurons. ARN14494 decreases neuronal death and caspase-3 activation in neurons, when the neuroinflammation is attenuated in astrocytes. These findings suggest that ARN14494 protects neurons from β-amyloid 1-42 induced neurotoxicity through a variety of mechanisms, including antioxidation, antiapoptosis, and anti-inflammation. SPT inhibition could therefore be a safe therapeutic strategy for ameliorating the pathology of Alzheimer's disease.
Collapse
Affiliation(s)
- Teresa De Vita
- Computational and Chemical Biology, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Clara Albani
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Natalia Realini
- D3 Validation, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Marco Migliore
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Abdul Basit
- Analytical Chemistry Facility, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Giuliana Ottonello
- Analytical Chemistry Facility, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Andrea Cavalli
- Computational and Chemical Biology, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
- Dipartimento di Farmacia e Biotecnologie, Università di Bologna, Via Belmeloro 6, 40126 Bologna, Italy
| |
Collapse
|
5
|
Xue X, Zhang W, Zhu J, Chen X, Zhou S, Xu Z, Hu G, Su C. Aquaporin-4 deficiency reduces TGF-β1 in mouse midbrains and exacerbates pathology in experimental Parkinson's disease. J Cell Mol Med 2019; 23:2568-2582. [PMID: 30680924 PMCID: PMC6433854 DOI: 10.1111/jcmm.14147] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 12/19/2018] [Accepted: 12/20/2018] [Indexed: 01/12/2023] Open
Abstract
Aquaporin-4 (AQP4), the main water-selective membrane transport protein in the brain, is localized to the astrocyte plasma membrane. Following the establishment of a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) model, AQP4-deficient (AQP4-/- ) mice displayed significantly stronger microglial inflammatory responses and remarkably greater losses of tyrosine hydroxylase (TH+ )-positive neurons than did wild-type AQP4 (AQP4+/+ ) controls. Microglia are the most important immune cells that mediate immune inflammation in PD. However, recently, few studies have reported why AQP4 deficiency results in more severe hypermicrogliosis and neuronal damage after MPTP treatment. In this study, transforming growth factor-β1 (TGF-β1), a key suppressive cytokine in PD onset and development, failed to increase in the midbrain and peripheral blood of AQP4-/- mice after MPTP treatment. Furthermore, the lower level of TGF-β1 in AQP4-/- mice partially resulted from impairment of its generation by astrocytes; reduced TGF-β1 may partially contribute to the uncontrolled microglial inflammatory responses and subsequent severe loss of TH+ neurons in AQP4-/- mice after MPTP treatment. Our study provides not only a better understanding of both aetiological and pathogenical factors implicated in the neurodegenerative mechanism of PD but also a possible approach to developing new treatments for PD via intervention in AQP4-mediated immune regulation.
Collapse
Affiliation(s)
- Xue Xue
- Jiangsu Key Laboratory of Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu, China.,Department of Nuclear Medicine, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Weiwei Zhang
- Jiangsu Key Laboratory of Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu, China.,Department of Pathogen Biology and Immunology, Nanjing University of traditional Chinese Medicine, Nanjing, Jiangsu, China
| | - Jifeng Zhu
- Jiangsu Key Laboratory of Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiaojun Chen
- Jiangsu Key Laboratory of Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Sha Zhou
- Jiangsu Key Laboratory of Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Zhipeng Xu
- Jiangsu Key Laboratory of Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Gang Hu
- Jiangsu Key Laboratory of Neurodegeneration, Department of Pharmacology, Nanjing Medical University, Nanjing, Jiangsu, China.,Department of Pharmacology, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China
| | - Chuan Su
- Jiangsu Key Laboratory of Pathogen Biology, Department of Pathogen Biology and Immunology, Nanjing Medical University, Nanjing, Jiangsu, China
| |
Collapse
|
6
|
Borgmann K, Ghorpade A. HIV-1, methamphetamine and astrocytes at neuroinflammatory Crossroads. Front Microbiol 2015; 6:1143. [PMID: 26579077 PMCID: PMC4621459 DOI: 10.3389/fmicb.2015.01143] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 10/05/2015] [Indexed: 12/30/2022] Open
Abstract
As a popular psychostimulant, methamphetamine (METH) use leads to long-lasting, strong euphoric effects. While METH abuse is common in the general population, between 10 and 15% of human immunodeficiency virus-1 (HIV-1) patients report having abused METH. METH exacerbates the severity and onset of HIV-1-associated neurocognitive disorders (HAND) through direct and indirect mechanisms. Repetitive METH use impedes adherence to antiretroviral drug regimens, increasing the likelihood of HIV-1 disease progression toward AIDS. METH exposure also directly affects both innate and adaptive immunity, altering lymphocyte numbers and activity, cytokine signaling, phagocytic function and infiltration through the blood brain barrier. Further, METH triggers the dopamine reward pathway and leads to impaired neuronal activity and direct toxicity. Concurrently, METH and HIV-1 alter the neuroimmune balance and induce neuroinflammation, which modulates a wide range of brain functions including neuronal signaling and activity, glial activation, viral infection, oxidative stress, and excitotoxicity. Pathologically, reactive gliosis is a hallmark of both HIV-1- and METH-associated neuroinflammation. Significant commonality exists in the neurotoxic mechanisms for both METH and HAND; however, the pathways dysregulated in astroglia during METH exposure are less clear. Thus, this review highlights alterations in astrocyte intracellular signaling pathways, gene expression and function during METH and HIV-1 comorbidity, with special emphasis on HAND-associated neuroinflammation. Importantly, this review carefully evaluates interventions targeting astrocytes in HAND and METH as potential novel therapeutic approaches. This comprehensive overview indicates, without a doubt, that during HIV-1 infection and METH abuse, a complex dialog between all neural cells is orchestrated through astrocyte regulated neuroinflammation.
Collapse
Affiliation(s)
- Kathleen Borgmann
- Department of Cell Biology and Immunology, University of North Texas Health Science Center Fort Worth, TX, USA
| | - Anuja Ghorpade
- Department of Cell Biology and Immunology, University of North Texas Health Science Center Fort Worth, TX, USA
| |
Collapse
|
7
|
Addington CP, Roussas A, Dutta D, Stabenfeldt SE. Endogenous repair signaling after brain injury and complementary bioengineering approaches to enhance neural regeneration. Biomark Insights 2015; 10:43-60. [PMID: 25983552 PMCID: PMC4429653 DOI: 10.4137/bmi.s20062] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/20/2015] [Accepted: 03/24/2015] [Indexed: 02/06/2023] Open
Abstract
Traumatic brain injury (TBI) affects 5.3 million Americans annually. Despite the many long-term deficits associated with TBI, there currently are no clinically available therapies that directly address the underlying pathologies contributing to these deficits. Preclinical studies have investigated various therapeutic approaches for TBI: two such approaches are stem cell transplantation and delivery of bioactive factors to mitigate the biochemical insult affiliated with TBI. However, success with either of these approaches has been limited largely due to the complexity of the injury microenvironment. As such, this review outlines the many factors of the injury microenvironment that mediate endogenous neural regeneration after TBI and the corresponding bioengineering approaches that harness these inherent signaling mechanisms to further amplify regenerative efforts.
Collapse
Affiliation(s)
- Caroline P Addington
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
| | - Adam Roussas
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
| | - Dipankar Dutta
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
| | - Sarah E Stabenfeldt
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
| |
Collapse
|
8
|
Improved fracture healing in patients with concomitant traumatic brain injury: proven or not? Mediators Inflamm 2015; 2015:204842. [PMID: 25873754 PMCID: PMC4385630 DOI: 10.1155/2015/204842] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 01/19/2015] [Indexed: 01/08/2023] Open
Abstract
Over the last 3 decades, scientific evidence advocates an association between traumatic brain injury (TBI) and accelerated fracture healing. Multiple clinical and preclinical studies have shown an enhanced callus formation and an increased callus volume in patients, respectively, rats with concomitant TBI. Over time, different substances (cytokines, hormones, etc.) were in focus to elucidate the relationship between TBI and fracture healing. Until now, the mechanism behind this relationship is not fully clarified and a consensus on which substance plays the key role could not be attained in the literature. In this review, we will give an overview of current concepts and opinions on this topic published in the last decade and both clinical and pathophysiological theories will be discussed.
Collapse
|
9
|
Martínez-Canabal A. Potential neuroprotective role of transforming growth factor β1 (TGFβ1) in the brain. Int J Neurosci 2014; 125:1-9. [PMID: 24628581 DOI: 10.3109/00207454.2014.903947] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
TGFβ1 is a growth factor that is known to be expressed in most neurodegenerative diseases and after vascular accidents in the brain. TGFβ1 downregulates the activity of activated microglia and promotes astrogliosis. It also prevents cell death by a known mechanism dependant on astrocytes and the secretion of the plasminogen activator inhibitor 1 (PAI-1). This mechanism can provide light on what is the mechanism of action of TGFβ1 as a protective factor and it can provide the pharmacological principles in which this pathway could be used with therapeutic purposes. TGFβ1 is upregulated in most neurodegenerative diseases, however, its expression appears dramatically blocked in Huntington's disease, the fastest of those diseases in progress after the onset. This fact suggests that TGFβ1 slows down the neurodegenerative process, preventing tissue damage and neural apoptotic death. However, the exact details of TGFβ1 action are still unknown and the physiological roles on the diseases are still mysterious. Interestingly, all the data regarding the roles of TGFβ1 in health and disease have been also confirmed with the use of transgenic knockouts and TGFβ1 overexpressing mice. What possibly came as a surprise from the study of TGFβ1 overexpressing models is that combining its neuroprotective and antiproliferative effects, this cytokine generates a significant disruption in the hippocampal circuitry with its consequent learning and memory deficit.
Collapse
Affiliation(s)
- Alonso Martínez-Canabal
- Department of Molecular Neuropathology, Cell Physiology Institute (IFC), Department of Cell Biology, Faculty of Sciences, National Autonomous University of Mexico (UNAM). Ciudad Universitaria, Circuito exterior S/N, Coyoacan, 04510 Mexico D.F. Mexico
| |
Collapse
|
10
|
A focus on mast cells and pain. J Neuroimmunol 2013; 264:1-7. [PMID: 24125568 DOI: 10.1016/j.jneuroim.2013.09.018] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 09/17/2013] [Accepted: 09/19/2013] [Indexed: 12/13/2022]
Abstract
Mast cells (MCs) are immunocytes with secretory functions that act locally in peripheral tissues to modulate local hemodynamics, nociceptor activation and pain. They are also able to infiltrate the central nervous system (CNS), especially the spinal cord and the thalamus, but their cerebral function remains an enigma. A role in regulating the opening of the blood-brain barrier has been proposed. Paracrine-like action of MCs on synaptic transmission might also signal a modulation of the nervous system by the immune system. In this review, we examine the link between MCs and nociceptive process, at the periphery as well as in the CNS.
Collapse
|
11
|
Slade GD, Conrad MS, Diatchenko L, Rashid NU, Zhong S, Smith S, Rhodes J, Medvedev A, Makarov S, Maixner W, Nackley AG. Cytokine biomarkers and chronic pain: association of genes, transcription, and circulating proteins with temporomandibular disorders and widespread palpation tenderness. Pain 2011; 152:2802-2812. [PMID: 22000099 DOI: 10.1016/j.pain.2011.09.005] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 08/29/2011] [Accepted: 09/08/2011] [Indexed: 12/22/2022]
Abstract
For reasons unknown, temporomandibular disorder (TMD) can manifest as localized pain or in conjunction with widespread pain. We evaluated relationships between cytokines and TMD without or with widespread palpation tenderness (TMD-WPT or TMD+WPT, respectively) at protein, transcription factory activity, and gene levels. Additionally, we evaluated the relationship between cytokines and intermediate phenotypes characteristic of TMD and WPT. In a case-control study of 344 females, blood samples were analyzed for levels of 22 cytokines and activity of 48 transcription factors. Intermediate phenotypes were measured by quantitative sensory testing and questionnaires asking about pain, health, and psychological status. Single nucleotide polymorphisms (SNPs) coding cytokines and transcription factors were genotyped. TMD-WPT cases had elevated protein levels of proinflammatory cytokine monocyte chemotactic protein (MCP-1) and antiinflammatory cytokine interleukin (IL)-1ra, whereas TMD+WPT cases had elevated levels of proinflammatory cytokine IL-8. MCP-1, IL-1ra, and IL-8 were differentially associated with experimental pain, self-rated pain, self-rated health, and psychological phenotypes. TMD-WPT and TMD+WPT cases had inhibited transcription activity of the antiinflammatory cytokine transforming growth factor β1 (TGFβ1). Interactions were observed between TGFβ1 and IL-8 SNPs: an additional copy of the TGFβ1 rs2241719 minor T allele was associated with twice the odds of TMD+WPT among individuals homozygous for the IL-8 rs4073 major A allele, and half the odds of TMD+WPT among individuals heterozygous for rs4073. These results demonstrate how pro- and antiinflammatory cytokines contribute to the pathophysiology of TMD and WPT in genetically susceptible people. Furthermore, they identify MCP-1, IL-1ra, IL-8, and TGFβ1 as potential diagnostic markers and therapeutic targets for pain in patients with TMD.
Collapse
Affiliation(s)
- Gary D Slade
- Center for Neurosensory Disorders, School of Dentistry, University of North Carolina, Chapel Hill, NC 27599, USA Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA Attagene, Inc, Morrisville, NC 27560, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Li J, Zhao H, Luo P, Gu Y. Functional cooperation of of IL-1β and RGS4 in the brachial plexus avulsion mediated brain reorganization. J Brachial Plex Peripher Nerve Inj 2010; 5:18. [PMID: 21138588 PMCID: PMC3017042 DOI: 10.1186/1749-7221-5-18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 12/07/2010] [Indexed: 01/27/2023] Open
Abstract
BACKGROUNDS There is considerable evidence that central nervous system is continuously modulated by activity, behavior and skill acquisition. This study is to examine the reorganization in cortical and subcortical regions in response to brachial plexus avulsion. METHODS Adult C57BL/6 mice were divided into four groups: control, 1, 3 and 6 month of brachial plexus avulsion. IL-1β, IL-6 and RGS4 expression in cortex, brainstem and spinal cord were detected by BiostarM-140 s microarray and real-time PCR. RGS4 subcellular distribution and modulation were further analyzed by primary neuron culture and Western Blot. RESULTS After 1, 3 and 6 months of brachial plexus avulsion, 49 (0 up, 49 down), 29 (17 up, 12 down), 13 (9 up, 4 down) genes in cerebral cortex, 40 (8 up, 32 down), 11 (7 up, 4 down), 137 (63 up, 74 down) in brainstem, 27 (14 up, 13 down), 33 (18 up, 15 down), 60 (29 up, 31 down) in spinal cord were identified. Among the regulated gene, IL-1β and IL-6 were sustainable enhanced in brain stem, while PKACβ and RGS4 were up-regulated throughout cerebral cortex, brainstem and spinal cord in 3 and 6 month of nerve injury. Intriguingly, subcellular distribution of RGS4 in above three regions was dependent on the functional correlation of PKA and IL-1β. CONCLUSION Data herein indicated that brachial plexus avulsion could efficiently initiate and perpetuate the brain reorganization. Network involved IL-1β and RGS4 signaling might implicate in the re-establish and strengthening of the local circuits at the cortical and subcortical levels.
Collapse
Affiliation(s)
- Jifeng Li
- Lab of Hand function reconstruction, Huashan Hospital, Fudan University, Shanghai, China
| | - Hui Zhao
- Lab of Hand function reconstruction, Huashan Hospital, Fudan University, Shanghai, China
| | - Pengbo Luo
- Lab of Hand function reconstruction, Huashan Hospital, Fudan University, Shanghai, China
| | - Yudong Gu
- Lab of Hand function reconstruction, Huashan Hospital, Fudan University, Shanghai, China
| |
Collapse
|
13
|
Kim JH, Min KJ, Seol W, Jou I, Joe EH. Astrocytes in injury states rapidly produce anti-inflammatory factors and attenuate microglial inflammatory responses. J Neurochem 2010; 115:1161-71. [PMID: 21039520 DOI: 10.1111/j.1471-4159.2010.07004.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Microglia are known to be a primary inflammatory cell type in the brain. However, microglial inflammatory responses are attenuated in the injured brain compared to those in cultured pure microglia. In the present study, we found that astrocytes challenged by oxygen-glucose deprivation (OGD) or H(2) O(2) released soluble factor(s) and attenuated microglial inflammatory responses. Conditioned medium prepared from astrocytes treated with OGD (OGD-ACM) or H(2) O(2) (H(2) O(2) -ACM) significantly reduced the levels of interferon-γ (IFN-γ)-induced microglial inflammatory mediators, including inducible nitric oxide synthase, at both the mRNA and protein levels. The anti-inflammatory effect of astrocytes appeared very rapidly (within 5min), but was not closely correlated with the extent of astrocyte damage. Both OGD-ACM and H(2) O(2) -ACM inhibited STAT nuclear signaling, as evidenced by a reduction in both STAT-1/3 binding to the IFN-γ-activated site and IFN-γ-activated site promoter activity. However, both phosphorylation and nuclear translocation of STAT-1/3 was unchanged in IFN-γ-treated microglia. The active component(s) in OGD-ACM were smaller than 3kDa, and displayed anti-inflammatory effects independent of protein synthesis. These results suggest that, in the injured brain, astrocytes may act as a controller to rapidly suppress microglial activation.
Collapse
Affiliation(s)
- Jong-Hyeon Kim
- Neuroscience Graduate Program, Ajou University School of Medicine, Suwon, Korea Brain Disease Research Center, Ajou University School of Medicine, Suwon, Korea
| | | | | | | | | |
Collapse
|
14
|
Merson TD, Binder MD, Kilpatrick TJ. Role of cytokines as mediators and regulators of microglial activity in inflammatory demyelination of the CNS. Neuromolecular Med 2010; 12:99-132. [PMID: 20411441 DOI: 10.1007/s12017-010-8112-z] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2009] [Accepted: 02/26/2010] [Indexed: 12/11/2022]
Abstract
As the resident innate immune cells of the central nervous system (CNS), microglia fulfil a critical role in maintaining tissue homeostasis and in directing and eliciting molecular responses to CNS damage. The human disease Multiple Sclerosis and animal models of inflammatory demyelination are characterized by a complex interplay between degenerative and regenerative processes, many of which are regulated and mediated by microglia. Cellular communication between microglia and other neural and immune cells is controlled to a large extent by the activity of cytokines. Here we review the role of cytokines as mediators and regulators of microglial activity in inflammatory demyelination, highlighting their importance in potentiating cell damage, promoting neuroprotection and enhancing cellular repair in a context-dependent manner.
Collapse
Affiliation(s)
- Tobias D Merson
- Florey Neuroscience Institutes, Centre for Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia.
| | | | | |
Collapse
|
15
|
Calzascia T, Loh JMS, Di Berardino-Besson W, Masson F, Guillaume P, Burkhardt K, Herrera PL, Dietrich PY, Walker PR. Peripheral tolerance limits CNS accumulation of CD8 T cells specific for an antigen shared by tumor cells and normal astrocytes. Glia 2008; 56:1625-36. [PMID: 18551629 DOI: 10.1002/glia.20715] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
T cell mediated immunotherapies are proposed for many cancers including malignant astrocytoma. As such therapies become more potent, but not necessarily more tumor-specific, the risk of collateral autoimmune damage to normal tissue increases. Tumors of the brain present significant challenges in this respect, as autoimmune destruction of brain tissue could have severe consequences. To investigate local immune reactivity toward a tumor-associated antigen in the brain, transgenic mice were generated that express a defined antigen (CW3 170-179) in astroglial cells. The resulting six transgenic mouse lines expressed the transgenic self-antigen in cells of the gastrointestinal tract and CNS compartments, or in the CNS alone. By challenging transgenic mice with tumor cells that express CW3, self/tumor-specific immune responses were visualized within a normal polyclonal T cell repertoire. A large expansion of the endogenous CW3 170-179-specific CD8 T cell population was observed in nontransgenic mice after both subcutaneous and intracerebral implantation of tumor cells. In contrast, CW3 170-179-specific immune responses were not observed in transgenic mice that exhibited extracerebral transgene expression. Importantly, in certain groups of mice in which transgene expression was restricted to the CNS, antigen-specific immune responses occurred when tumor was implanted subcutaneously, but not intracerebrally. This local immune tolerance in the brain was induced via peripheral (extrathymic) rather than central (thymic) tolerance mechanisms. Thus, this study highlights the role of regional immune regulation in the prevention of autoimmunity in the brain, and the potential impact of these mechanisms for brain tumor immunotherapy.
Collapse
Affiliation(s)
- Thomas Calzascia
- Centre of Oncology, Geneva University Hospitals and University of Geneva, rue Micheli-du-Crest 24, Geneva, Switzerland
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Laird MD, Vender JR, Dhandapani KM. Opposing Roles for Reactive Astrocytes following Traumatic Brain Injury. Neurosignals 2008; 16:154-64. [DOI: 10.1159/000111560] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
|
17
|
Wang XF, Yin L, Hu JG, Huang LD, Yu PP, Jiang XY, Xu XM, Lu PH. Expression and localization of p80 interleukin-1 receptor protein in the rat spinal cord. J Mol Neurosci 2007; 29:45-53. [PMID: 16757809 DOI: 10.1385/jmn:29:1:45] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 11/11/2022]
Abstract
The biological effects of interleukin (IL)-1 are mediated by two distinct receptors, the p80 or type I (IL-1RI) and p68 or type II (IL-1RII) receptors. Because IL-1RII has a short, 29-amino acid cytoplasmic domain which may not be sufficient for signaling, there is considerable evidence indicating that IL-1 may signal exclusively through the IL-1RI receptor. Here, we report the expression, distribution, and cellular localization of the IL-1RI protein in the adult rat spinal cord in vivo and embryonic spinal cord in vitro. We found that IL-1RI was expressed in both the gray and white matter throughout the entire length of the spinal cord and was localized in neurons of the anterior horn, astrocytes, oligodendrocytes, and central canal ependymal cells. Interestingly, resting microglia were negative for IL-1RI. In primary cultures obtained from the embryonic day (E) 15 rats, IL-1RI was expressed in neurons, astrocytes, and oligodendrocytes as well as microglia. These data provide both in vivo and in vitro evidence that neurons and glial cells express the IL-1RI proteins. The differential expression of IL-1RI in the developing, but not mature, microglia may indicate the difference of these cells in response to IL-1 stimuli during maturation. The distribution and cellular localization of IL-1RI proteins in the spinal cord provide a molecular basis for understanding the reciprocal interaction between the immune and the central nervous systems.
Collapse
Affiliation(s)
- Xiao-Fei Wang
- Department of Neurobiology, Shanghai Second Medical University, Shanghai, P.R. China
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Bramanti V, Campisi A, Tomassoni D, Costa A, Fisichella A, Mazzone V, Denaro L, Avitabile M, Amenta F, Avola R. Astroglial-Conditioned Media and Growth Factors Modulate Proliferation and Differentiation of Astrocytes in Primary Culture. Neurochem Res 2006; 32:49-56. [PMID: 17151914 DOI: 10.1007/s11064-006-9224-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Accepted: 11/06/2006] [Indexed: 10/23/2022]
Abstract
Astroglial conditioned media (ACM) influence the development and maturation of cultured nerve cells and modulate neuron-glia interaction. To clarify mechanisms of astroglial cell proliferation/differentiation in culture, incorporation of [methyl-3H]-thymidine or [5,6-3H]-uridine in cultured astrocytes was assessed. Cultures were pre-treated with epidermal growth factor (EGF), insulin (INS), insulin-like growth factor-I (IGF-I), and basic fibroblast growth factor (bFGF) and subsequently with ACM. DNA labeling revealed a marked stimulatory effect of ACM from 15 days in vitro (DIV) cultures in 30 DIV astrocytes after 12 h pre-treatment with growth factors. The main effects were found after INS or EGF pre-treatment in 30 DIV cultures. ACM collected from 15 or 60 or 90 DIV increased RNA labeling of 15 and 30 DIV astrocyte cultures, being the highest value that of 30 DIV cultures added with ACM from 90 DIV. The findings of increased DNA labeling after EGF or INS pre-treatment in 30 DIV cultures, followed by addition of ACM from 15 DIV cultures, suggest that these phenomena may depend by extra cellular signal-regulated kinase 1 (ERK1) activation.
Collapse
Affiliation(s)
- Vincenzo Bramanti
- Section of Biochemistry and Molecular Biology, Department of Chemical Sciences, University of Catania, Viale Andrea Doria, 6, Catania, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Lin HW, Basu A, Druckman C, Cicchese M, Krady JK, Levison SW. Astrogliosis is delayed in type 1 interleukin-1 receptor-null mice following a penetrating brain injury. J Neuroinflammation 2006; 3:15. [PMID: 16808851 PMCID: PMC1533808 DOI: 10.1186/1742-2094-3-15] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Accepted: 06/30/2006] [Indexed: 01/23/2023] Open
Abstract
The cytokines IL-1α and IL-1β are induced rapidly after insults to the CNS, and their subsequent signaling through the type 1 IL-1 receptor (IL-1R1) has been regarded as essential for a normal astroglial and microglial/macrophage response. To determine whether abrogating signaling through the IL-1R1 will alter the cardinal astrocytic responses to injury, we analyzed molecules characteristic of activated astrocytes in response to a penetrating stab wound in wild type mice and mice with a targeted deletion of IL-1R1. Here we show that after a stab wound injury, glial fibrillary acidic protein (GFAP) induction on a per cell basis is delayed in the IL-1R1-null mice compared to wild type counterparts. However, the induction of chondroitin sulfate proteoglycans, tenascin, S-100B as well as glutamate transporter proteins, GLAST and GLT-1, and glutamine synthetase are independent of IL-1RI signaling. Cumulatively, our studies on gliosis in the IL-1R1-null mice indicate that abrogating IL-1R1 signaling delays some responses of astroglial activation; however, many of the important neuroprotective adaptations of astrocytes to brain trauma are preserved. These data recommend the continued development of therapeutics to abrogate IL-1R1 signaling to treat traumatic brain injuries. However, astroglial scar related proteins were induced irrespective of blocking IL-1R1 signaling and thus, other therapeutic strategies will be required to inhibit glial scarring.
Collapse
Affiliation(s)
- Hsiao-Wen Lin
- Department of Neurology and Neuroscience, UMDNJ-New Jersey Medical School, Newark, NJ 07103, USA
| | - Anirban Basu
- National Brain Research Centre, Gurgaon – 122 050, India
| | - Charles Druckman
- Dept. of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Michael Cicchese
- Dept. of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - J Kyle Krady
- Dept. of Neural and Behavioral Sciences, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Steven W Levison
- Department of Neurology and Neuroscience, UMDNJ-New Jersey Medical School, Newark, NJ 07103, USA
| |
Collapse
|
20
|
Dhar A, Gardner J, Borgmann K, Wu L, Ghorpade A. Novel role of TGF-beta in differential astrocyte-TIMP-1 regulation: implications for HIV-1-dementia and neuroinflammation. J Neurosci Res 2006; 83:1271-80. [PMID: 16496359 PMCID: PMC3820372 DOI: 10.1002/jnr.20787] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Astrocyte production of tissue inhibitor of metalloproteinase (TIMP)-1 is important in central nervous system (CNS) homeostasis and inflammatory diseases such as HIV-1-associated dementia (HAD). TIMPs and matrix metalloproteinases (MMPs) regulate the remodeling of the extracellular matrix. An imbalance between TIMPs and MMPs is associated with many pathologic conditions. Our recently published studies uniquely demonstrate that HAD patients have reduced levels of TIMP-1 in the brain. Astrocyte-TIMP-1 expression is differentially regulated in acute and chronic inflammatory conditions. In this and the adjoining report (Gardner et al., 2006), we investigate the mechanisms that may be involved in differential TIMP-1 regulation. One mechanism for TIMP-1 downregulation is the production of anti-inflammatory molecules, which can activate signaling pathways during chronic inflammation. We investigated the contribution of transforming growth factor (TGF)-signaling in astrocyte-MMP/TIMP-1-astrocyte regulation. TGF-beta1 and beta2 levels were upregulated in HAD brain tissues. Co-stimulation of astrocytes with IL-1beta and TGF-beta mimicked the TIMP-1 downregulation observed with IL-1beta chronic activation. Measurement of astrocyte-MMP protein levels showed that TGF-beta combined with IL-1beta increased MMP-2 and decreased proMMP-1 expression compared to IL-1beta alone. We propose that one of the mechanisms involved in TIMP-1 downregulation may be through TGF-signaling in chronic immune activation. These studies show a novel extracellular regulatory loop in astrocyte-TIMP-1 regulation.
Collapse
Affiliation(s)
- Alok Dhar
- Laboratory of Cellular Neuroimmunology, University of Nebraska Medical Center, Omaha, Nebraska
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, Nebraska
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska
| | - Jessica Gardner
- Laboratory of Cellular Neuroimmunology, University of Nebraska Medical Center, Omaha, Nebraska
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, Nebraska
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska
| | - Kathleen Borgmann
- Laboratory of Cellular Neuroimmunology, University of Nebraska Medical Center, Omaha, Nebraska
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, Nebraska
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska
| | - Li Wu
- Laboratory of Cellular Neuroimmunology, University of Nebraska Medical Center, Omaha, Nebraska
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, Nebraska
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska
| | - Anuja Ghorpade
- Laboratory of Cellular Neuroimmunology, University of Nebraska Medical Center, Omaha, Nebraska
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, Nebraska
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska
- Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska
| |
Collapse
|
21
|
Ueberham U, Zobiak B, Ueberham E, Brückner MK, Boriss H, Arendt T. Differentially expressed cortical genes contribute to perivascular deposition in transgenic mice with inducible neuron‐specific expression of TGF‐β1. Int J Dev Neurosci 2005; 24:177-86. [PMID: 16386398 DOI: 10.1016/j.ijdevneu.2005.11.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Accepted: 11/10/2005] [Indexed: 10/25/2022] Open
Abstract
In the brain the expression of transforming growth factor beta1 (TGF-beta1) is involved both in neuroprotective and neurodegenerative processes. Recently, we have established a transgenic mouse model with inducible neuron-specific expression of TGF-beta1 based on the tetracycline-regulated gene expression system. A long-term expression of TGF-beta1 results in persisting perivascular thioflavin-positive depositions, which did not disappear even though the transgene synthesis was repressed completely by administration of doxycycline. Formation and composition of these depositions are hardly elucidated. The aim of this study was to identify TGF-beta1 responding genes potentially participating in forming these depositions. To address this problem we have compared the cortical mRNA expression pattern of TGF-beta1 expressing mice with mice impeded to express the transgenic protein using oligonucleotide microarray analysis. Differential gene expression was further characterized by quantitative real-time reverse transcription-polymerase chain reaction including animals, where the long-lasting TGF-beta1 expression was repressed. While no change of amyloid precursor protein RNA expression level was detected, various genes strongly involved in calcium homeostasis, tissue mineralization or vascular calcification were identified differentially expressed. It is suggested, that these genes might contribute to the perivascular depositions in the TGF-beta1 expressing mice.
Collapse
Affiliation(s)
- Uwe Ueberham
- Paul Flechsig Institute for Brain Research, Department of Neuroanatomy, University of Leipzig, Jahnallee 59, D-04109 Leipzig, Germany.
| | | | | | | | | | | |
Collapse
|
22
|
Dubayle D, Servière J, Menétrey D. Evidence for serotonin influencing the thalamic infiltration of mast cells in rat. J Neuroimmunol 2005; 159:20-30. [PMID: 15652399 DOI: 10.1016/j.jneuroim.2004.08.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2004] [Revised: 08/24/2004] [Accepted: 08/30/2004] [Indexed: 11/30/2022]
Abstract
Serotonin (5-HT) is involved in neuroimmunomodulation. We analyzed the effects of sumatriptan, a 5-HT(1B/1D) receptor agonist, and ondansetron, a 5-HT(3) receptor antagonist, on thalamic mast cell (TMC) population, the only immunocytes known to infiltrate the brain in physiological conditions. Only sumatriptan was effective, significantly increasing TMC numbers versus controls, and especially those containing 5-HT. 5-HT(1B) receptors are concentrated in the median eminence on non-serotonergic axonal endings, probably hypothalamic terminal fibers, involved in hypothalamic-pituitary neuroendocrine modulating processes. TMC variations could reflect serotonergic actions on these fibers. TMCs would thus be cellular interfaces mediating immune action in the nervous system in relation with the hormonal status of the organism.
Collapse
Affiliation(s)
- D Dubayle
- CNRS UMR 8119 Neurophysique et physiologie, Université René Descartes, UFR Biomédicale, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France.
| | | | | |
Collapse
|
23
|
Cherian S, Thoresen M, Silver IA, Whitelaw A, Love S. Transforming growth factor-betas in a rat model of neonatal posthaemorrhagic hydrocephalus. Neuropathol Appl Neurobiol 2005; 30:585-600. [PMID: 15540999 DOI: 10.1111/j.1365-2990.2004.00588.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Posthaemorrhagic ventricular dilatation (PHVD) is a common complication of intraventricular haemorrhage in premature infants. The aim of this study was to investigate the role of transforming growth factor-betas (TGF-betas), a family of polypeptides with potent desmoplastic properties, in the aetiology of PHVD in a newly developed neonatal rat model of this disorder. Pups were injected with citrated rat blood or artificial cerebrospinal fluid (ACSF) into alternate lateral ventricles on postnatal days 7 and 8. The brains were perfusion-fixed 14 days later and immunohistochemistry was performed for TGF-beta1, -beta2 and -beta3, p44/42 mitogen-activated protein (MAP) kinases, and the extracellular matrix proteins laminin, vitronectin and fibronectin. Ventricular dilatation occurred in 58.3% of animals injected with blood and 36.7% of those injected with ACSF. Periventricular immunoreactivity for TGF-beta1 and -beta2 increased in injected animals irrespective of the presence or absence of ventricular dilatation, although the levels of both isoforms tended to be higher in animals with hydrocephalus. TGF-beta3 immunoreactivity was elevated in hydrocephalic rats only. The immunolabelling for phosphorylated p44/42 MAP kinases rose in a pattern similar to that for TGF-beta1 and -beta2. Expression of TGF-betas was accompanied by deposition of the extracellular matrix proteins fibronectin, laminin and vitronectin. The changes caused by injection of ACSF were the same as those caused by injection of blood. Our results raise the possibility that expression of TGF-betas, together with extracellular matrix protein deposition, may be involved in the development and/or maintenance of hydrocephalus after ventricular distension due to haemorrhage in the neonate.
Collapse
Affiliation(s)
- S Cherian
- Department of Clinical Science (South Bristol), University of Bristol, Bristol, UK
| | | | | | | | | |
Collapse
|
24
|
Wang CM, Chang YY, Sun SH. Activation of P2X7 purinoceptor-stimulated TGF-beta 1 mRNA expression involves PKC/MAPK signalling pathway in a rat brain-derived type-2 astrocyte cell line, RBA-2. Cell Signal 2004; 15:1129-37. [PMID: 14575868 DOI: 10.1016/s0898-6568(03)00112-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The present study investigates the receptor and mechanisms involved in ATP-stimulated transforming growth factor-beta 1 (TGF-beta 1) mRNA expression of a type-2 astrocyte cell line, RBA-2. RT-PCR analysis revealed that RBA-2 type-2 astrocytes possess abundant P2X(4) and P2X(7) receptors. ATP and P2X(7) receptor-sensitive agonist, BzATP, both stimulated TGF-beta 1 mRNA expression in a time and dose-dependent manner. The stimulation required a minimum of 500 muM ATP; BzATP was much more potent that ATP, and P2X(7)-selective antagonist, oATP, inhibited the effects. In addition, ATP metabolites ADP, AMP and adenosine were ineffective in stimulation of TGF-beta 1 mRNA expression. Thus, the effect of ATP was mediated through the P2X(7) receptors. To investigate further the mechanisms by which the P2X(7) receptor mediated the TGF-beta 1 mRNA expression, the cells were treated with inhibitors for mitogen-activated kinase (MAPK) or protein kinase C (PKC), PD98059 or GF109203X, respectively. Both PD98059 and GF109203X inhibited the ATP-stimulated TGF-beta 1 mRNA expression. Furthermore, ATP and BzATP stimulated ERK1/2 activation and the activation was inhibited by PKC inhibitors, GF109203X and Gö6976. In conclusion, activation of P2X(7) receptors enhanced TGF-beta 1 mRNA expression and the effect involved PKC/MAPK signalling pathway in RBA-2 type-2 astrocytes.
Collapse
MESH Headings
- Adenosine/pharmacology
- Adenosine Diphosphate/pharmacology
- Adenosine Monophosphate/pharmacology
- Adenosine Triphosphate/analogs & derivatives
- Adenosine Triphosphate/pharmacology
- Animals
- Astrocytes/drug effects
- Astrocytes/metabolism
- Astrocytes/physiology
- Blotting, Northern
- Blotting, Western
- Brain/cytology
- Carbazoles/pharmacology
- Cell Line
- Dose-Response Relationship, Drug
- Flavonoids/pharmacology
- Gene Expression
- Indoles/pharmacology
- Kinetics
- MAP Kinase Signaling System/physiology
- Maleimides/pharmacology
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases/antagonists & inhibitors
- Mitogen-Activated Protein Kinases/metabolism
- Phosphorylation/drug effects
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Receptors, Purinergic P2/analysis
- Receptors, Purinergic P2/genetics
- Receptors, Purinergic P2/physiology
- Receptors, Purinergic P2X4
- Receptors, Purinergic P2X7
- Reverse Transcriptase Polymerase Chain Reaction
- Tetradecanoylphorbol Acetate/pharmacology
- Transforming Growth Factor beta/genetics
- Transforming Growth Factor beta1
Collapse
Affiliation(s)
- Chia-Mei Wang
- Institute of Neuroscience, College of Life Science, National Yang Ming University, Brain Research Center, University System of Taiwan, Taipei, Taiwan, ROC
| | | | | |
Collapse
|
25
|
Stoll G, Schroeter M, Jander S, Siebert H, Wollrath A, Kleinschnitz C, Brück W. Lesion-associated expression of transforming growth factor-beta-2 in the rat nervous system: evidence for down-regulating the phagocytic activity of microglia and macrophages. Brain Pathol 2004; 14:51-8. [PMID: 14997937 PMCID: PMC8095793 DOI: 10.1111/j.1750-3639.2004.tb00497.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The mechanisms that control the phagocytic activities of microglia and macrophages during disorders of the nervous system are largely unknown. In the present investigation, we assessed the functional role of transforming growth factor (TGF)beta2 in vitro and studied TGFbeta-2mRNA and protein expression in two CNS lesion paradigms in vivo characterized by fundamental differences in microglia/macrophage behaviour: optic nerve crush exhibiting slow, and focal cerebral ischemia exhibiting rapid phagocytic transformation. Furthermore, we used sciatic nerve crush injury as a PNS lesion paradigm comparable to brain ischemia in its rapid phagocyte response. In normal and degenerating optic nerves, astrocytes strongly and continuously expressed TGF-beta2 immunoreactivity. In contrast, TGF-beta2 was downregulated in Schwann cells of degenerating sciatic nerves, and was not expressed by reactive astrocytes in the vicinity of focal ischemic brain lesions during the acute phagocytic phase. In line with its differential lesion-associated expression pattern, exogenous TGF-beta2 suppressed spontaneous myelin phagocytosis by microglia/macrophages in a mouse ex vivo assay of CNS and PNS Wallerian degeneration. In conclusion, we have identified TGF-beta2 as a nervous system intrinsic cytokine that could account for the differential regulation of phagocytic activities of microglia and macrophages during injury.
Collapse
Affiliation(s)
- Guido Stoll
- Department of Neurology, Julius-Maximilians Universität Würzburg, Germany.
| | | | | | | | | | | | | |
Collapse
|
26
|
Kuhlow CJ, Krady JK, Basu A, Levison SW. Astrocytic ceruloplasmin expression, which is induced by IL-1beta and by traumatic brain injury, increases in the absence of the IL-1 type 1 receptor. Glia 2003; 44:76-84. [PMID: 12951659 DOI: 10.1002/glia.10273] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
IL-1alpha and IL-1beta are induced immediately after insults to the brain, and signaling through the type 1 IL-1 receptor is essential for a normal microglial and astroglial response to injury. To better understand which genes are induced in astrocytes by IL-1beta, we used the unbiased technique of differential display to analyze mouse astroglial gene expression after IL-1beta treatment. Two novel genes were induced, as well as the gene for ceruloplasmin, a ferroxidase with antioxidant properties. Ceruloplasmin was analyzed further by Northern and Western blot. RNA and protein levels of ceruloplasmin were increased when astrocytes were treated with IL-1beta. To determine whether the IL-1 type 1 receptor (IL-1R1) is essential for the injury-induced expression of ceruloplasmin, a Western blot analysis was performed after a traumatic brain injury on mice that were IL-1R1-deficient. Ceruloplasmin increased significantly above controls after injury; however, injury-induced levels of ceruloplasmin were lower in IL-1R1-deficient (2.7-fold increase) than in the wild-type animals (3.5-fold increase). These data indicate that while IL-1R1 deletion has a slight effect on ceruloplasmin expression, it is not essential for either the basal or the induced expression of ceruloplasmin in vivo. Since ceruloplasmin buffers free copper, oxidizes ferrous iron, and catalyzes the dismutation of free radicals, increased levels of ceruloplasmin likely protect neurons and glia from sustaining damage after injury. Furthermore, as the IL-1R1 has been proposed to be a target for achieving neuroprotection after injury, these data suggest that the protection afforded by ceruloplasmin will be retained even when the IL-1R1 is antagonized.
Collapse
Affiliation(s)
- Christopher J Kuhlow
- Department of Neuroscience and Anatomy, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA
| | | | | | | |
Collapse
|
27
|
Boche D, Cunningham C, Gauldie J, Perry VH. Transforming growth factor-beta 1-mediated neuroprotection against excitotoxic injury in vivo. J Cereb Blood Flow Metab 2003; 23:1174-82. [PMID: 14526228 DOI: 10.1097/01.wcb.0000090080.64176.44] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Ischemic preconditioning is a phenomenon that describes how a sublethal ischemic insult can induce tolerance to subsequent ischemia. This phenomenon has been observed after focal or global ischemia in different animal models. However, the hypothesis that bacterial infection might lead to neuronal tolerance to injury has not been investigated. To mimic cerebral bacterial infection, we injected bacterial lipopolysaccharide (LPS) in the right dorsal hippocampus, followed 24 hours later by an excitotoxic lesion using kainic acid in the mouse model. Quantification of lesion size after cresyl violet counterstaining revealed that LPS pretreatment afforded neuroprotection to CA3 neurons against KA challenge. To investigate the events underlying this protection, we studied the cytokine profile induced after LPS injection. Interleukin (IL)-1 beta and transforming growth factor beta 1 (TGF-beta 1) were the main cytokines expressed at 24 hours after LPS injection. Because IL-1 beta has been described as deleterious in acute injury, we decided to investigate the function of TGF-beta 1. An adenovirus expressing a constitutively active form of TGF-beta 1 was injected intracerebrally 1 week before the induction of excitotoxic lesion, and neuronal protection was observed. To confirm the neuroprotective role of TGF-beta 1, the TGF-beta 1 adenovirus was replaced by recombinant human TGF-beta 1 protein and total neuroprotection was observed. Furthermore, the antibody-mediated blocking of TGF-beta 1 action prevented the protective effect of pretreatment with LPS. We have demonstrated in vivo that the cerebral tolerance phenomenon induced by LPS pretreatment is mediated by TGF-beta 1 cytokine.
Collapse
Affiliation(s)
- Delphine Boche
- CNS Inflammation Group, Southampton Neuroscience Group, School of Biological Sciences, University of Southampton, Southampton, Hampshire, UK.
| | | | | | | |
Collapse
|
28
|
Kim HC, Bing G, Kim SJ, Jhoo WK, Shin EJ, Bok Wie M, Ko KH, Kim WK, Flanders KC, Choi SG, Hong JS. Kainate treatment alters TGF-beta3 gene expression in the rat hippocampus. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2002; 108:60-70. [PMID: 12480179 DOI: 10.1016/s0169-328x(02)00514-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In order to evaluate the role of transforming growth factor (TGF)-beta3 in the neurodegenerative process, we examined the levels of mRNA and immunocytochemical distribution for TGF-beta3 in the rat hippocampus after systemic kainic acid (KA) administration. Hippocampal TGF-beta3 mRNA level was reduced 3 h after KA injection. However, the levels of TGF-beta3 mRNA were elevated 1 day post-KA and lasted for at least 30 days. A mild TGF-beta3 immunoreactivity (TGF-beta3-IR) in the Ammon's horn and a moderate TGF-beta3-IR in the dentate granule cells were observed in the normal hippocampus. The CA1 and CA3 neurons lost their TGF-beta3-IR, while TGF-beta3-positive glia-like cells proliferated mainly throughout the CA1 sector and had an intense immunoreactivity at 7, 15 and 30 days after KA. This immunocytochemical distribution of TGF-beta3-positive non-neuronal populations was similar to that of glial fibrillary acidic protein (GFAP)-positive cells. Double labeling immunocytochemical analysis demonstrated colocalization of TGF-beta3- and GFAP-immunoreactivity in the same cells. These findings suggest a compensatory mechanism of astrocytes for the synthesis of TGF-beta3 protein in response to KA-induced neurodegeneration. In addition, exogenous TGF-beta3 (5 or 10 ng/i.c.v.) significantly attenuated KA-induced seizures and neuronal damages in a dose-related manner. Therefore, our results suggest that TGF-beta3 plays an important role in protective mechanisms against KA-induced neurodegeneration.
Collapse
Affiliation(s)
- Hyoung-Chun Kim
- Neurotoxicology Program, College of Pharmacy, Korea Institute of Drug Abuse, Kangwon National University, Chunchon 200-701, South Korea.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
The type 1 interleukin-1 receptor is essential for the efficient activation of microglia and the induction of multiple proinflammatory mediators in response to brain injury. J Neurosci 2002. [PMID: 12122068 DOI: 10.1523/jneurosci.22-14-06071.2002] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Interleukin-1 (IL-1) is induced immediately after insults to the brain, and elevated levels of IL-1 have been strongly implicated in the neurodegeneration that accompanies stroke, Alzheimer's disease, and multiple sclerosis. In animal models, antagonizing IL-1 has been shown to reduce cell death; however, the basis for this protection has not been elucidated. Here we analyzed the response to penetrating brain injury in mice lacking the type 1 IL-1 receptor (IL-1R1) to determine which cellular and molecular mediators of tissue damage require IL-1 signaling. At the cellular level, fewer amoeboid microglia/macrophages appeared adjacent to the injured brain tissue in IL-1R1 null mice, and those microglia present at early postinjury intervals retained their resting morphology. Astrogliosis also was mildly abrogated. At the molecular level, cyclooxygenase-2 (Cox-2) and IL-6 expression were depressed and delayed. Interestingly, basal levels of Cox-2, IL-1, and IL-6 were significantly lower in the IL-1R1 null mice. In addition, stimulation of vascular cell adhesion molecule-1 mRNA was depressed in the IL-1R1 null mice, and correspondingly, there was reduced diapedesis of peripheral macrophages in the IL-1R1 null brain after injury. This observation correlated with a reduced number of Cox-2+ amoeboid phagocytes adjacent to the injury. In contrast, several molecular aspects of the injury response were normal, including expression of tumor necrosis factor-alpha and the production of nerve growth factor. Because antagonizing IL-1 protects neural cells in experimental models of stroke and multiple sclerosis, our data suggest that cell preservation is achieved by abrogating microglial/macrophage activation and the subsequent self-propagating cycle of inflammation.
Collapse
|
30
|
Yang MS, Park EJ, Sohn S, Kwon HJ, Shin WH, Pyo HK, Jin B, Choi KS, Jou I, Joe EH. Interleukin-13 and -4 induce death of activated microglia. Glia 2002; 38:273-80. [PMID: 12007140 DOI: 10.1002/glia.10057] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
When the brain suffers injury, microglia migrate to the damaged sites and become activated. These activated microglia are not detected several days later and the mechanisms underlying their disappearance are not well characterized. In this study, we demonstrate that interleukin (IL)-13, an anti-inflammatory cytokine, selectively induces cell death of activated microglia in vitro. Cell death was detected 4 days after the coaddition of IL-13 with any one of the microglial activators, lipopolysaccharide (LPS), ganglioside, or thrombin. This cell death occurred in a time-dependent manner. LPS, ganglioside, thrombin, or IL-13 alone did not induce cell death. Among anti-inflammatory cytokines, IL-4 mimicked the effect of IL-13, while TGF-beta did not. Cells treated with IL-13 plus LPS, or IL-13 plus ganglioside, showed the characteristics of apoptosis when analyzed by electron microscopy and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining. Electron micrographs also showed microglia engulfing neighboring dead cells. We propose that IL-13 and IL-4 induce death of activated microglia, and that this process is important for prevention of chronic inflammation that can cause tissue damage.
Collapse
Affiliation(s)
- Myung-Soon Yang
- Department of Pharmacology, Ajou University School of Medicine, Suwon, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
Cytokines have been implicated as mediators and inhibitors of diverse forms of neurodegeneration. They are induced in response to brain injury and have diverse actions that can cause, exacerbate, mediate and/or inhibit cellular injury and repair. Here we review evidence for the contribution of cytokines to acute neurodegeneration, focusing primarily on interleukin 1 (IL-1), tumour necrosis factor-alpha (TNFalpha) and transforming growth factor-beta (TGFbeta). TGFbeta seems to exert primarily neuroprotective actions, whereas TNFalpha might contribute to neuronal injury and exert protective effects. IL-1 mediates ischaemic, excitotoxic and traumatic brain injury, probably through multiple actions on glia, neurons and the vasculature. Understanding cytokine action in acute neurodegeneration could lead to novel and effective therapeutic strategies, some of which are already in clinical trials.
Collapse
|
32
|
Lenzlinger PM, Morganti-Kossmann MC, Laurer HL, McIntosh TK. The duality of the inflammatory response to traumatic brain injury. Mol Neurobiol 2001; 24:169-81. [PMID: 11831551 DOI: 10.1385/mn:24:1-3:169] [Citation(s) in RCA: 302] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
One and a half to two million people sustain a traumatic brain injury (TBI) in the US each year, of which approx 70,000-90,000 will suffer from long-term disability with dramatic impacts on their own and their families' lives and enormous socio-economic costs. Brain damage following traumatic injury is a result of direct (immediate mechanical disruption of brain tissue, or primary injury) and indirect (secondary or delayed) mechanisms. These secondary mechanisms involve the initiation of an acute inflammatory response, including breakdown of the blood-brain barrier (BBB), edema formation and swelling, infiltration of peripheral blood cells and activation of resident immunocompetent cells, as well as the intrathecal release of numerous immune mediators such as interleukins and chemotactic factors. An overview over the inflammatory response to trauma as observed in clinical and in experimental TBI is presented in this review. The possibly harmful/beneficial sequelae of post-traumatic inflammation in the central nervous system (CNS) are discussed using three model mediators of inflammation in the brain, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and transforming growth factor-beta (TGF-beta). While the former two may act as important mediators for the initiation and the support of post-traumatic inflammation, thus causing additional cell death and neurologic dysfunction, they may also pave the way for reparative processes. TGF-beta, on the other hand, is a potent anti-inflammatory agent, which may also have some deleterious long-term effects in the injured brain. The implications of this duality of the post-traumatic inflammatory response for the treatment of brain-injured patients using anti-inflammatory strategies are discussed.
Collapse
Affiliation(s)
- P M Lenzlinger
- Department of Neurosurgery, University of Pennsylvania, Veterans Administration Medical Center, Philadelphia 19104-6316, USA
| | | | | | | |
Collapse
|
33
|
Morgan TE, Rozovsky I, Sarkar DK, Young-Chan CS, Nichols NR, Laping NJ, Finch CE. Transforming growth factor-beta1 induces transforming growth factor-beta1 and transforming growth factor-beta receptor messenger RNAs and reduces complement C1qB messenger RNA in rat brain microglia. Neuroscience 2001; 101:313-21. [PMID: 11074155 DOI: 10.1016/s0306-4522(00)00387-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Transforming growth factor-beta1 is a multifunctional peptide with increased expression during Alzheimer's disease and other neurodegenerative conditions which involve inflammatory mechanisms. We examined the autoregulation of transforming growth factor-beta1 and transforming growth factor-beta receptors and the effects of transforming growth factor-beta1 on complement C1q in brains of adult Fischer 344 male rats and in primary glial cultures. Perforant path transection by entorhinal cortex lesioning was used as a model for the hippocampal deafferentation of Alzheimer's disease. In the hippocampus ipsilateral to the lesion, transforming growth factor-beta1 peptide was increased >100-fold; the messenger RNAs encoding transforming growth factor-beta1, transforming growth factor-beta type I and type II receptors were also increased, but to a smaller degree. In this acute lesion paradigm, microglia are the main cell type containing transforming growth factor-beta1, transforming growth factor-beta type I and II receptor messenger RNAs, shown by immunocytochemistry in combination with in situ hybridization. Autoregulation of the transforming growth factor-beta1 system was examined by intraventricular infusion of transforming growth factor-beta1 peptide, which increased hippocampal transforming growth factor-beta1 messenger RNA levels in a dose-dependent fashion. Similarly, transforming growth factor-beta1 increased levels of transforming growth factor-beta1 messenger RNA and transforming growth factor-beta type II receptor messenger RNA (IC(50), 5pM) and increased release of transforming growth factor-beta1 peptide from primary microglia cultures. Interactions of transforming growth factor-beta1 with complement system gene expression are also indicated, because transforming growth factor-beta1 decreased C1qB messenger RNA in the cortex and hippocampus, after intraventricular infusion, and in cultured glia. These indications of autocrine regulation of transforming growth factor-beta1 in the rodent brain support a major role of microglia in neural activities of transforming growth factor-beta1 and give a new link between transforming growth factor-beta1 and the complement system. The auto-induction of the transforming growth factor-beta1 system has implications for transgenic mice that overexpress transforming growth factor-beta1 in brain cells and for its potential role in amyloidogenesis.
Collapse
Affiliation(s)
- T E Morgan
- Andrus Gerontology Center and Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089-0191, USA.
| | | | | | | | | | | | | |
Collapse
|
34
|
Li QQ, Bever CT. Th1 cytokines stimulate RANTES chemokine secretion by human astroglial cells depending on de novo transcription. Neurochem Res 2001; 26:125-33. [PMID: 11478739 DOI: 10.1023/a:1011042711631] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Beta-chemokines induce the directional migration of monocytes and T lymphocytes that are implicated in the pathogenesis of multiple sclerosis (MS) lesions. RANTES is a member of the beta-chemokine family that has been detected in the lesions of MS patients. However, the cellular sources of RANTES message and the molecular basis for the regulation of its production in MS lesions are not well understood. Glial cells may be a major source of RANTES in vivo and have been shown to produce RANTES in vitro. Thus, the objective of this study was to establish a model system for studying the regulation of RANTES expression by cytokines in cultured human glial cells, and to determine the mechanism involved in the process. We show that the Th1 cytokines TNF-alpha and IL-1beta independently induce RANTES mRNA and chemokine levels in human U-251 MG astroglial cells, and that these effects are time- and concentration-dependent. In addition, we demonstrate that both cytokines increased the rate of transcription of the RANTES gene, as estimated by in vitro nuclear transcript elongation assays. The transcriptional activity in TNF-alpha-treated U-251 MG cells started to increase at 2 h and peaked at 8 h, with levels more than 14 times greater than controls. We further show that NF-kappaB may play a critical role in the up-regulation of human RANTES gene expression in this system. Gel shift assays revealed an induction of in vitro nuclear extract binding activity to the NF-kappaB element of RANTES in cells incubated with the Th1 cytokines. These observations suggest that human astroglia, within diseased brain, may be stimulated to produce RANTES chemokine in response to TNF-alpha and IL-1beta, and that this effect of the Th1 cytokines is attributed to increase of transcription.
Collapse
Affiliation(s)
- Q Q Li
- Department of Neurology, University of Maryland School of Medicine, Baltimore 21201, USA.
| | | |
Collapse
|
35
|
Vitkovic L, Maeda S, Sternberg E. Anti-inflammatory cytokines: expression and action in the brain. Neuroimmunomodulation 2001; 9:295-312. [PMID: 12045357 DOI: 10.1159/000059387] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Transforming growth factor-beta(1) (TGF-beta(1)) and interleukin (IL)-10 gene expression is equivocal in normal brain and upregulated in over a dozen central and peripheral diseases/disorders. The patterns of specific expression of cytokines differ in these diseases. Published data indicate that these cytokines are produced by and act on both neurons and glial cells. Although their actions are commonly viewed as 'anti-inflammatory', they protect neurons and downregulate the responses of glial cells to diseases/disorders in the absence of inflammation. Their actions counterbalance the actions of elevated IL-1 and/or tumor necrosis factor-alpha to maintain homeostasis. Their therapeutic potential will be realized by improving our understanding of their place in neural cytokine networks.
Collapse
Affiliation(s)
- L Vitkovic
- Integrative Neural Immune Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
| | | | | |
Collapse
|
36
|
Böttner M, Krieglstein K, Unsicker K. The transforming growth factor-betas: structure, signaling, and roles in nervous system development and functions. J Neurochem 2000; 75:2227-40. [PMID: 11080174 DOI: 10.1046/j.1471-4159.2000.0752227.x] [Citation(s) in RCA: 221] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Transforming growth factor-betas (TGF-betas) are among the most widespread and versatile cytokines. Here, we first provide a brief overview of their molecular biology, biochemistry, and signaling. We then review distribution and functions of the three mammalian TGF-beta isoforms, beta1, beta2, and beta3, and their receptors in the developing and adult nervous system. Roles of TGF-betas in the regulation of radial glia, astroglia, oligodendroglia, and microglia are addressed. Finally, we review the current state of knowledge concerning the roles of TGF-betas in controlling neuronal performances, including the regulation of proliferation of neuronal precursors, survival/death decisions, and neuronal differentiation.
Collapse
Affiliation(s)
- M Böttner
- Neuroanatomy and Center for Neuroscience, University of Heidelberg, Heidelberg, Germany
| | | | | |
Collapse
|
37
|
Denk PO, Roth-Eichhorn S, Gressner AM, Knorr M. Effect of cytokines on regulation of the production of transforming growth factor beta-1 in cultured human Tenon's capsule fibroblasts. Eur J Ophthalmol 2000; 10:110-5. [PMID: 10887920 DOI: 10.1177/112067210001000203] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE Transforming growth factor-beta1 (TGF-beta1) is thought to play a pivotal role in the regulation of the wound healing process after glaucoma filtering surgery. The aim of the present study was to investigate whether platelet-derived growth factor isoforms (PDGF-AA, PDGF-BB), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), interleukin-1beta (IL-1beta) and transforming growth factor-beta1 (TGF-beta1) modulate the production of latent and/or active TGF-beta1 by cultured human Tenon's capsule fibroblasts (HTF). METHODS Human Tenon's capsule fibroblasts were seeded at two different densities (30 cells/mm2 and 150 cells/mm2) and stimulated for five days with PDGF-AA, PDGF-BB, bFGF, EGF, IL-1beta and TGF-beta1. Control cells were treated with serum-free medium (WM/F12). The concentrations of latent and active TGF-beta1 in the medium were determined using an immunoassay before and after activation of TGF-beta1 by transient acidification. RESULTS The concentration of latent TGF-beta1 in conditioned media from HTF seeded at high density (150 cells/mm2) significantly increased after stimulation with 5 ng/ml TGF-beta1 (151.5 +/-41.7 pg/ml) or 10 ng/ml IL-1beta (45.7+/-8.1 pg/ml). The concentration of active TGF-beta1 in conditioned media also significantly increased after stimulation of HTF with 5 ng/ml TGF-beta1 (48.4+/-27.5 pg/ml). CONCLUSIONS The present results indicate that TGF-beta1 is the most potent inducer of its own synthesis in HTF. Activation of an autocrine TGF-beta1 loop may play a role in the wound healing response after glaucoma filtering surgery.
Collapse
Affiliation(s)
- P O Denk
- Department of General Ophthalmology, University Eye Clinic, Tübingen, Germany.
| | | | | | | |
Collapse
|
38
|
Gao Y, Ng YK, Lin JY, Ling EA. Expression of immunoregulatory cytokines in neurons of the lateral hypothalamic area and amygdaloid nuclear complex of rats immunized against human IgG. Brain Res 2000; 859:364-8. [PMID: 10719087 DOI: 10.1016/s0006-8993(00)02001-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Present results showed that interleukin-1 (IL-1), IL-6 and transforming growth factor-beta (TGF-beta) were constitutively expressed in the supraoptic and paraventricular nuclei of the rat hypothalamus. Immunoreactive cells were also detected, but to a lesser extent, in other parts of hypothalamus as well as in the cerebral cortex. In rats immunized with IgG, there was moderate increase in immunoreactivities of the cytokines. A notable feature, however, was the induction of the cytokine expression in the lateral hypothalamic area and the amygdaloid nuclear complex, suggesting that the neurons in these two areas are involved in possible immune regulation.
Collapse
Affiliation(s)
- Y Gao
- Department of Immunology, Peking Union Medical College, Beijing, China
| | | | | | | |
Collapse
|
39
|
Lee SJ, Zhou T, Choi C, Wang Z, Benveniste EN. Differential regulation and function of Fas expression on glial cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:1277-85. [PMID: 10640741 DOI: 10.4049/jimmunol.164.3.1277] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Fas/Apo-1 is a member of the TNF receptor superfamily that signals apoptotic cell death in susceptible target cells. Fas or Fas ligand (FasL)-deficient mice are relatively resistant to the induction of experimental allergic encephalomyelitis, implying the involvement of Fas/FasL in this disease process. We have examined the regulation and function of Fas expression in glial cells (astrocytes and microglia). Fas is constitutively expressed by primary murine microglia at a low level and significantly up-regulated by TNF-alpha or IFN-gamma stimulation. Primary astrocytes express high constitutive levels of Fas, which are not further affected by cytokine treatment. In microglia, Fas expression is regulated at the level of mRNA expression; TNF-alpha and IFN-gamma induced Fas mRNA by approximately 20-fold. STAT-1alpha and NF-kappaB activation are involved in IFN-gamma- or TNF-alpha-mediated Fas up-regulation in microglia, respectively. The cytokine TGF-beta inhibits basal expression of Fas as well as cytokine-mediated Fas expression by microglia. Upon incubation of microglial cells with FasL-expressing cells, approximately 20% of cells underwent Fas-mediated cell death, which increased to approximately 60% when cells were pretreated with either TNF-alpha or IFN-gamma. TGF-beta treatment inhibited Fas-mediated cell death of TNF-alpha- or IFN-gamma-stimulated microglial cells. In contrast, astrocytes are resistant to Fas-mediated cell death, however, ligation of Fas induces expression of the chemokines macrophage inflammatory protein-1beta (MIP-1beta), MIP-1alpha, and MIP-2. These data demonstrate that Fas transmits different signals in the two glial cell populations: a cytotoxic signal in microglia and an inflammatory signal in the astrocyte.
Collapse
Affiliation(s)
- S J Lee
- Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | | | | | | | |
Collapse
|
40
|
Abstract
It is well established that mast cells (MCs) occur within the CNS of many species. Furthermore, their numbers can increase rapidly in adults in response to altered physiological conditions. In this study we found that early postpartum rats had significantly more mast cells in the thalamus than virgin controls. Evidence from semithin sections from these females suggested that mast cells were transiting across the medium-sized blood vessels. We hypothesized that the increases in mast cell number were caused by their migration into the neural parenchyma. To this end, we purified rat peritoneal mast cells, labeled them with the vital dyes PKH26 or CellTracker Green, and injected them into host animals. One hour after injection, dye-filled cells, containing either histamine or serotonin (mediators stored in mast cells), were located close to thalamic blood vessels. Injected cells represented approximately 2-20% of the total mast cell population in this brain region. Scanning confocal microscopy confirmed that the biogenic amine and the vital dye occurred in the same cell. To determine whether the donor mast cells were within the blood-brain barrier, we studied the localization of dye-marked donor cells and either Factor VIII, a component of endothelial basal laminae, or glial fibrillary acidic protein, the intermediate filament found in astrocytes. Serial section reconstructions of confocal images demonstrated that the mast cells were deep to the basal lamina, in nests of glial processes. This is the first demonstration that mast cells can rapidly penetrate brain blood vessels, and this may account for the rapid increases in mast cell populations after physiological manipulations.
Collapse
|
41
|
|
42
|
Morganti-Kossmann MC, Hans VH, Lenzlinger PM, Dubs R, Ludwig E, Trentz O, Kossmann T. TGF-beta is elevated in the CSF of patients with severe traumatic brain injuries and parallels blood-brain barrier function. J Neurotrauma 1999; 16:617-28. [PMID: 10447073 DOI: 10.1089/neu.1999.16.617] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Traumatic brain injury (TBI) induces local and systemic immunologic changes, release of cytokines, and cell activation. Perpetuation of these cascades may contribute to secondary damage to the brain. Therefore, the ability of the antiinflammatory mediator transforming growth factor-beta (TGF-beta) to downregulate intrathecal immunoactivation may be of fundamental value for diminishing the incidence and extent of secondary insults. In this study, the release of TGF-beta into cerebrospinal fluid (CSF) and serum of 22 patients with severe TBI was analyzed with respect to the function of the blood-brain barrier (BBB) for 21 days. Levels of TGF-beta in CSF increased to their maximum on the first day (median, 1.26 ng/mL), thereafter decreasing gradually over time. Median TGF-beta values in serum always remained within the reference interval (6.5 to 71.5 ng/mL). Daily assessment of the CSF-serum albumin quotient (QA) and of the CSF-serum TGF-beta quotient (QTGF-beta) showed a strong correlation between maximal QTGF-beta and QA, indicating a passage of this cytokine from the periphery to the intrathecal compartment across the BBB. However, calculation of the TGF-beta index (QTGF-beta/Q(A)) suggested a cerebral production of TGF-beta in 9 of 22 patients. Levels of TGF-beta could not be correlated with extent of initial injury by computed tomography (CT), CD4/CD8 ratios, acute lung injury, or clinical outcome as rated by the Glasgow Outcome Scale (GOS). Although increased levels of TGF-beta in CSF seem to parallel BBB function, a partial intrathecal production is suggested, possibly modulated by elevation of interleukin-6 (IL-6). Thus, TGF-beta may function as a factor in the complex cytokine network following TBI, acting as an antiinflammatory and neuroprotective mediator.
Collapse
|
43
|
Abstract
Mast cells are found in the brain of many species. Although a considerable body of information is available concerning the development and differentiation of peripheral mast cells, little is known about brain mast cells. In the present study, the ontogeny of mast cells in the dove brain was followed by using three markers: acidic toluidine blue, alcian blue/safranin, and an antiserum to gonadotropin-releasing hormone (GnRH). Mast cells first appear in the pia on embryonic day (E)13-14 in ovo, then along blood vessels extending from the pia into the telencephalon on posthatch day 4-5, and in the medial habenula at week 3. Medial habenular mast cell numbers increase during development, peaking in peripubertal birds, and declining thereafter. Several measures indicate that mast cells mature within the medial habenula: there is an increase in the intensity of metachromasia, a switch from alcian blue granules in young animals to mixed alcian blue and safranin granules in older animals, and an increase in GnRH-like immunoreactivity. These results were extended by using electron microscopy. The architecture of mast cell granules evolved from electron lucent with small electron dense deposits at E15 to more electron dense granules with complex patterns of internal structure by 2 months. Ultrastructural immunocytochemistry for the GnRH-like peptide at 1 month revealed both immunopositive and negative cells, suggesting that the acquisition of this phenotype is not simultaneous across the population. Thus, immature mast cells infiltrate the central nervous system and undergo in situ differentiation within the neuropil.
Collapse
Affiliation(s)
- X Zhuang
- Department of Psychology, Columbia University, New York, New York 10027, USA
| | | | | |
Collapse
|
44
|
Racke MK, Lovett-Racke AE. Bystander suppression in experimental autoimmune encephalomyelitis: where and how does it occur? RESEARCH IN IMMUNOLOGY 1998; 149:820-7; discussion 851-2, 855-60. [PMID: 9923638 DOI: 10.1016/s0923-2494(99)80010-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M K Racke
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | |
Collapse
|
45
|
Abstract
Cytokines and chemokines have been implicated in contributing to the initiation, propagation and regulation of immune and inflammatory responses. Also, these soluble mediators have important roles in contributing to a wide array of neurological diseases such as multiple sclerosis, AIDS Dementia Complex, stroke and Alzheimer's disease. Cytokines and chemokines are synthesized within the central nervous system by glial cells and neurons, and have modulatory functions on these same cells via interactions with specific cell-surface receptors. In this article, I will discuss the ability of glial cells and neurons to both respond to, and synthesize, a variety of cytokines. The emphasize will be on three select cytokines; interferon-gamma (IFN-gamma), a cytokine with predominantly proinflammatory effects; interleukin-6 (IL-6), a cytokine with both pro- and anti-inflammatory properties; and transforming growth factor-beta (TGF-beta), a cytokine with predominantly immunosuppressive actions. The significance of these cytokines to neurological diseases with an immunological component will be discussed.
Collapse
Affiliation(s)
- E N Benveniste
- Department of Cell Biology, University of Alabama at Birmingham, 35294-0005, USA.
| |
Collapse
|
46
|
Fok-Seang J, DiProspero NA, Meiners S, Muir E, Fawcett JW. Cytokine-induced changes in the ability of astrocytes to support migration of oligodendrocyte precursors and axon growth. Eur J Neurosci 1998; 10:2400-15. [PMID: 9749768 DOI: 10.1046/j.1460-9568.1998.00251.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Repair of demyelination in the CNS requires that oligodendrocyte precursors (OPs) migrate, divide and then myelinate. Repair of axon damage requires axonal regeneration. Limited remyelination and axon regeneration occurs soon after injury, but usually ceases in a few days. In vivo and in vitro experiments have shown that astrocytic environments are not very permissive for migration of OPs or for axonal re-growth. Yet remyelination and axon sprouting early after injury occurs in association with astrocytes, while later astrocytes can exclude remyelination and prevent axon regeneration. A large and changing cast of cytokines are released following CNS injury, so we investigated whether some of these alone or in combination can affect the ability of astrocytes to support migration of OPs and neuritic outgrowth. Interleukin (IL) 1alpha, tumour necrosis factor alpha, transforming growth factor (TGF) beta, basic fibroblast growth factor (bFGF), platelet-derived growth factor and epidermal growth factor alone exerted little or no effect on migration of OPs on astrocytes, whereas interferon (IFN) gamma was inhibitory. The combination of IL-1alpha + bFGF was found to be pro-migratory, and this effect could be neutralized by TGFbeta. We also examined neuritic outgrowth from dorsal root ganglion explants in three-dimensional astrocyte cultures treated with cytokines and found that IL-1alpha + bFGF greatly increased axon outgrowth and that this effect could be blocked by TGFbeta and IFNgamma. All these effects were absent or much smaller when OP migration or axon growth was tested on laminin, so the main effect of the cytokines was via astrocytes. The cytokine effects did not correlate with expression on astrocytes of laminin, fibronectin, tenascin, chondroitin sulphate proteoglycan, N-cadherin, polysialyated NCAM (PSA-NCAM), tissue plasminogen activator (tPA) or urokinase (uPA).
Collapse
Affiliation(s)
- J Fok-Seang
- Physiological Laboratory, University of Cambridge, UK
| | | | | | | | | |
Collapse
|
47
|
Vincent VA, Tilders FJ, Van Dam AM. Production, regulation and role of nitric oxide in glial cells. Mediators Inflamm 1998; 7:239-55. [PMID: 9792334 PMCID: PMC1781853 DOI: 10.1080/09629359890929] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Affiliation(s)
- V A Vincent
- Research Institute Neurosciences Free University, Medical Faculty, Department of Pharmacology, Amsterdam, The Netherlands
| | | | | |
Collapse
|
48
|
Pratt BM, McPherson JM. TGF-beta in the central nervous system: potential roles in ischemic injury and neurodegenerative diseases. Cytokine Growth Factor Rev 1997; 8:267-92. [PMID: 9620642 DOI: 10.1016/s1359-6101(97)00018-x] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The Transforming Growth Factor-betas (TGF-beta) are a group of multifunctional proteins whose cellular sites of production and action are widely distributed throughout the body, including the central nervous system (CNS). Within the CNS, various isoforms of TGF-beta are produced by both glial and neural cells. When evaluated in either cell culture or in vivo models, the various isoforms of TGF-beta have been shown to have potent effects on the proliferation, function, or survival of both neurons and all three glial cell types, astrocytes, microglia and oligodendrocytes. TGF-beta has also been shown to play a role in several forms of acute CNS pathology including ischemia, excitotoxicity and several forms of neurodegenerative diseases including multiple sclerosis, Parkinson's disease, AIDS dementia and Alzheimer's disease.
Collapse
Affiliation(s)
- B M Pratt
- Protein and Cell Therapeutics Development Group, Genzyme Tissue Repair Division, Genzyme Corporation, Framingham, MA 01701-9322, USA
| | | |
Collapse
|
49
|
da Cunha A, Jefferson JJ, Tyor WR, Glass JD, Jannotta FS, Cottrell JR, Resau JH. Transforming growth factor-beta1 in adult human microglia and its stimulated production by interleukin-1. J Interferon Cytokine Res 1997; 17:655-64. [PMID: 9402103 DOI: 10.1089/jir.1997.17.655] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Ameboid microglia express human immunodeficiency virus 1 (HIV-1) more frequently than do ramified microglia. These two microglial subtypes might also differ in the frequency with which they express transforming growth factor-beta1 (TGF-beta1), a cytokine that regulates HIV-1 expression in monocytes. Results described here show that ameboid and ramified microglia express TGF-beta1. In brain tissues from HIV-1-infected individuals as compared with seronegative controls, ameboid rather than ramified microglia more frequently expressed TGF-beta1. Ameboid microglia, isolated and cultured from postmortem adult human brain more frequently expressed TGF-beta1 in presence of interleukin-1(IL-1), a cytokine that is elevated in brains of HIV-1-infected individuals when compared with seronegative controls. The stimulation of TGF-beta1 by IL-1 was dose and time dependent, occurring with ameboid microglia isolated from either frontal cortex or globus pallidus but not midbrain pons. Ameboid microglia are similar to the RCA-1-positive cells that form clusters, called microglial nodules, in the brain of HIV-1-infected individuals. Pathologic conditions, such as disseminated microglial nodules, are associated with HIV-1 encephalitis, direct infection of the brain, and moderate to severe neurologic impairment. TGF-beta1 expression in ameboid microglia may play a role in HIV-1 neuropathogenesis.
Collapse
Affiliation(s)
- A da Cunha
- Laboratory of Cell Biology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | | | | | | | | | | | | |
Collapse
|
50
|
Zhuang X, Silverman AJ, Silver R. Mast cell number and maturation in the central nervous system: influence of tissue type, location and exposure to steroid hormones. Neuroscience 1997; 80:1237-45. [PMID: 9284073 DOI: 10.1016/s0306-4522(97)00052-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
While it is well established that brain mast cells are usually associated with the cerebral vasculature, in ring doves mast cells lie directly in the neuropil of the medial habenula. During normal development mast cells enter the habenula and complete their differentiation in situ. In the present study, we asked what characteristics of the medial habenula contribute to mast cell entry and differentiation. Grafts of embryonic habenula or control optic tectal grafts were placed in the lateral ventricle or anterior chamber of the eye. Transplantation alters the location of the habenula as well as its neural and vascular connections. Three groups of hosts were used for the ventricular grafts: four-month-old and killed three months after transplantation; four-month-old and killed seven months later, and two- to three-year-old gonadectomized males killed three months later. Hosts for the intraocular grafts were four months of age and killed three months later. Mast cells were present in the habenular grafts but not in the control tissue. Mast cells in three- and seven-month-old grafts were phenotypically immature when compared to those of hosts. They contained fewer metachromatic granules, fewer granules immunoreactive to an antiserum against gonadotropin-releasing hormone, and no highly-sulphated proteoglycans. As previously described, gonadectomized adults had fewer mast cells in their medial habenula than did intact animals, but there was no change in mast cell number in habenular grafts. The current experiments indicate that the occurrence and survival of mast cells can occur within the microenvironment of the medial habenula, but that maturation of these cells requires the normal connections of this nucleus. Furthermore, gonadectomy appears to alter mast cell number in the medial habenula by generating a secondary signal which the transplanted tissue is incapable of receiving or processing.
Collapse
Affiliation(s)
- X Zhuang
- Department of Psychology, Columbia University, New York, NY 10027, U.S.A
| | | | | |
Collapse
|