1
|
STAT3 in medulloblastoma: a key transcriptional regulator and potential therapeutic target. Mol Biol Rep 2022; 49:10635-10652. [PMID: 35716286 DOI: 10.1007/s11033-022-07694-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/08/2022] [Indexed: 10/18/2022]
Abstract
Medulloblastoma is the most common malignant brain tumor of childhood accounting for about 60% of all pediatric embryonal tumors. Despite improvements in the overall survival rate, this tumor still lacks an efficient, reliable, and less toxic therapeutic approach. Characterization of the molecular mechanisms involved in medulloblastoma initiation and progression is a crucial step for the development of effective therapies. Signal transducer and activator of transcription 3 is a convergence point for several signaling cascades that are implicated in medulloblastoma tumorigenesis. Accumulated evidence has revealed the pivotal role of signal transducer and activator of transcription 3 in medulloblastoma pathogenesis such as proliferation, survival, angiogenesis, and immunosuppression as well as maintenance, drug resistance, and recurrence. In this review, we focus on the role of signal transducer and activator of transcription 3 in medulloblastoma tumorigenesis and discuss the recent advances of signal transducer and activator of transcription 3 inhibition as a promising developed strategy for medulloblastoma therapy.
Collapse
|
2
|
Gruol DL, Melkonian C, Huitron-Resendiz S, Roberts AJ. Alcohol alters IL-6 Signal Transduction in the CNS of Transgenic Mice with Increased Astrocyte Expression of IL-6. Cell Mol Neurobiol 2021; 41:733-750. [PMID: 32447612 PMCID: PMC7680720 DOI: 10.1007/s10571-020-00879-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 05/15/2020] [Indexed: 12/30/2022]
Abstract
Neuroimmune factors, including the cytokine interleukin-6 (IL-6), are important chemical regulators of central nervous system (CNS) function under both physiological and pathological conditions. Elevated expression of IL-6 occurs in the CNS in a variety of disorders associated with altered CNS function, including excessive alcohol use. Alcohol-induced production of IL-6 has been reported for several CNS regions including the cerebellum. Cerebellar actions of alcohol occur through a variety of mechanisms, but alcohol-induced changes in signal transduction, transcription, and translation are known to play important roles. IL-6 is an activator of signal transduction that regulates gene expression. Thus, alcohol-induced IL-6 production could contribute to cerebellar effects of alcohol by altering gene expression, especially under conditions of chronic alcohol abuse, where IL-6 levels could be habitually elevated. To gain an understanding of the effects of alcohol on IL-6 signal transduction, we studied activation/expression of IL-6 signal transduction partners STAT3 (Signal Transducer and Activator of Transcription), CCAAT-enhancer binding protein (C/EBP) beta, and p42/p44 mitogen-activated protein kinase (MAPK) at the protein level. Cerebella of transgenic mice that express elevated levels of astrocyte produced IL-6 in the CNS were studied. Results show that the both IL-6 and chronic intermittent alcohol exposure/withdrawal affect IL-6 signal transduction partners and that the actions of IL-6 and alcohol interact to alter activation/expression of IL-6 signal transduction partners. The alcohol/IL-6 interactions may contribute to cerebellar actions of alcohol, whereas the effects of IL-6 alone may have relevance to cerebellar changes occurring in CNS disorders associated with elevated levels of IL-6.
Collapse
Affiliation(s)
- Donna L Gruol
- Neuroscience Department, SR301, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA.
| | - Claudia Melkonian
- Neuroscience Department, SR301, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | | | - Amanda J Roberts
- Animal Models Core Facility, The Scripps Research Institute, La Jolla, CA, 92037, USA
| |
Collapse
|
3
|
Gruol DL, Hernandez RV, Roberts A. Alcohol Enhances Responses to High Frequency Stimulation in Hippocampus from Transgenic Mice with Increased Astrocyte Expression of IL-6. Cell Mol Neurobiol 2020; 41:1299-1310. [PMID: 32562098 DOI: 10.1007/s10571-020-00902-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/09/2020] [Indexed: 12/29/2022]
Abstract
Recent studies show that alcohol exposure can induce glial production of neuroimmune factors in the CNS. Of these, IL-6 has gained attention because it is involved in a number of important physiological and pathophysiological processes that could be affected by alcohol-induced CNS production of IL-6, particularly under conditions of excessive alcohol use. For example, IL-6 has been shown to play a role in hippocampal behaviors and synaptic plasticity (long-term potentiation; LTP) associated with memory and learning. Surprisingly, in our in vitro studies of LTP at the Schaffer collateral to CA1 pyramidal neuron synapse in hippocampus from transgenic mice that express elevated levels of astrocyte produced IL-6 (TG), LTP was not altered by the increased levels of IL-6. However, exposure to acute alcohol revealed neuroadaptive changes that served to protect LTP against the alcohol-induced reduction of LTP observed in hippocampus from non-transgenic control mice (WT). Here we examined the induction phase of LTP to assess if presynaptic neuroadaptive changes occurred in the hippocampus of TG mice that contributed to the resistance of LTP to alcohol. Results are consistent with a role for IL-6-induced neuroadaptive effects on presynaptic mechanisms involved in transmitter release in the resistance of LTP to alcohol in hippocampus from the TG mice. These actions are important with respect to a role for IL-6 in physiological and pathophysiological processes in the CNS and in CNS actions of alcohol, especially when excessive alcohol used is comorbid with conditions associated with elevated levels of IL-6 in the CNS.
Collapse
Affiliation(s)
- Donna L Gruol
- Neuroscience Department, SR301, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA.
| | - Ruben V Hernandez
- Neuroscience Department, SR301, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Amanda Roberts
- Animal Models Core Facility, The Scripps Research Institute, La Jolla, CA, 92037, USA
| |
Collapse
|
4
|
McGregor G, Clements L, Farah A, Irving AJ, Harvey J. Age-dependent regulation of excitatory synaptic transmission at hippocampal temporoammonic-CA1 synapses by leptin. Neurobiol Aging 2018; 69:76-93. [PMID: 29860205 PMCID: PMC6075472 DOI: 10.1016/j.neurobiolaging.2018.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 04/17/2018] [Accepted: 05/04/2018] [Indexed: 12/15/2022]
Abstract
The hippocampus is a key target for the hormone leptin and leptin regulation of excitatory synaptic transmission at Schaffer-collateral-CA1 synapses during aging are well documented. However, little is known about the age-dependent actions of leptin at the temporoammonic (TA) input to CA1 neurons. Here we show that leptin induces a novel form of N-methyl-D-aspartate receptor-dependent long-term depression (LTD) at adult (12-24 weeks old) TA-CA1 synapses. Leptin-induced LTD requires activation of canonical Janus tyrosine kinase 2- signal transducer and activator of transcription signaling and removal of GluA1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors from synapses. Moreover, leptin-induced LTD is occluded by activity-dependent LTD at TA-CA1 synapses. By contrast, leptin has no effect on excitatory synaptic transmission at aged (12-14 months old) TA-CA1 synapses, and low-frequency stimulation also fails to induce LTD at this age. These findings demonstrate clear age-related alterations in the leptin sensitivity of TA-CA1 synapses and provide valuable information on how the leptin system alters with age. As leptin has been linked to Alzheimer's disease, these findings have important implications for understanding of age-related disorders such as Alzheimer's disease.
Collapse
Affiliation(s)
- Gemma McGregor
- Division of Neuroscience, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Leigh Clements
- Division of Neuroscience, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Adham Farah
- Division of Neuroscience, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Andrew J Irving
- School of Biomolecular and Biomedical Science, The Conway Institute, University College Dublin, Dublin, Ireland
| | - Jenni Harvey
- Division of Neuroscience, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK.
| |
Collapse
|
5
|
Wu Y, Huang XF, Bell C, Yu Y. Ginsenoside Rb1 improves leptin sensitivity in the prefrontal cortex in obese mice. CNS Neurosci Ther 2017; 24:98-107. [PMID: 29130652 DOI: 10.1111/cns.12776] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 10/17/2017] [Accepted: 10/18/2017] [Indexed: 01/01/2023] Open
Abstract
AIM Obesity impairs leptin-induced regulation of brain-derived neurotrophic factor (BDNF) expression and synaptogenesis, which has been considered to be associated with the incidence of neuronal degenerative diseases, cognitive decline, and depression. Ginsenoside Rb1 (Rb1), a major bioactive component of ginseng, is known to have an antiobesity effect and improve cognition. This study examined whether Rb1 can improve central leptin effects on BDNF expression and synaptogenesis in the prefrontal cortex during obesity using an in vivo and an in vitro model. RESULT Ginsenoside Rb1 (Rb1) chronic treatment improved central leptin sensitivity, leptin-JAK2-STAT3 signaling, and leptin-induced regulation of BDNF expression in the prefrontal cortex of high-fat diet-induced obese mice. In cultured prefrontal cortical neurons, palmitic acid, the saturated fat, impaired leptin-induced BDNF expression, reduced the immunoreactivity and mRNA expression of synaptic proteins, and impaired leptin-induced neurite outgrowth and synaptogenesis. Importantly, Rb1 significantly prevented these pernicious effects induced by palmitic acid. CONCLUSION These results indicate that Rb1 reverses central leptin resistance and improves leptin-BDNF-neurite outgrowth and synaptogenesis in the prefrontal cortical neurons. Thus, Rb1 supplementation may be a beneficial avenue to treat obesity-associated neurodegenerative disorders.
Collapse
Affiliation(s)
- Yizhen Wu
- School of Medicine, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
| | - Xu-Feng Huang
- School of Medicine, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogen Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Christopher Bell
- School of Medicine, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
| | - Yinghua Yu
- School of Medicine, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.,Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogen Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| |
Collapse
|
6
|
Olde Engberink A, Hernandez R, de Graan P, Gruol DL. Rapamycin-Sensitive Late-LTP is Enhanced in the Hippocampus of IL-6 Transgenic Mice. Neuroscience 2017; 367:200-210. [PMID: 29104031 DOI: 10.1016/j.neuroscience.2017.10.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 10/07/2017] [Accepted: 10/27/2017] [Indexed: 12/13/2022]
Abstract
The neuroimmune factor IL-6 has been shown to regulate hippocampal long-term potentiation (LTP), an activity-dependent enhancement of synaptic transmission that plays a central role in memory and learning. This IL-6 action was demonstrated with relatively short IL-6 exposure, and may reflect physiological actions of IL-6. IL-6 is also expressed chronically at elevated levels in the central nervous system (CNS) under pathological conditions such as neurological disorders. Little is known about the effects IL-6 on LTP under such conditions, an issue that we are addressing by electrophysiological recordings from CA1 pyramidal neurons of hippocampal slices from transgenic mice that persistently express elevated levels of IL-6 in the CNS (IL-6 tg). The current studies examined the long-lasting phase of LTP (late LTP; L-LTP) and the potential involvement mammalian target of rapamycin (mTOR), a known regulator of L-LTP and a downstream partner of IL-6 signal transduction pathways. Results show that basal synaptic transmission and L-LTP were increased in hippocampal slices from IL-6 tg mice compared to slices from non-transgenic (non-tg) control mice. An inhibitor of mTOR, rapamycin, reduced L-LTP in slices from both genotypes, and eliminated the difference in magnitude of L-LTP between IL-6 and non-tg hippocampus. There were no genotypic effect of rapamycin on basal synaptic transmission, but synaptic responses during the LTP induction protocol were reduced in IL-6 tg slices, an effect that could contribute to the reduction of L-LTP in the IL-6 tg slices. These results indicate that persistently increased levels of IL-6 can lead to alterations in mTOR regulation of L-LTP, possibly affecting learning and memory.
Collapse
Affiliation(s)
- Anneke Olde Engberink
- Neuroscience Department, The Scripps Research Institute, San Diego, USA; Department of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht, Netherlands
| | - Ruben Hernandez
- Neuroscience Department, The Scripps Research Institute, San Diego, USA
| | - Pierre de Graan
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht, Netherlands
| | - Donna L Gruol
- Neuroscience Department, The Scripps Research Institute, San Diego, USA.
| |
Collapse
|
7
|
McGregor G, Irving AJ, Harvey J. Canonical JAK‐STAT signaling is pivotal for long‐term depression at adult hippocampal temporoammonic‐CA1 synapses. FASEB J 2017; 31:3449-3466. [DOI: 10.1096/fj.201601293rr] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 04/11/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Gemma McGregor
- Division of NeuroscienceSchool of MedicineNinewells Hospital and Medical SchoolUniversity of Dundee Dundee United Kingdom
| | - Andrew J. Irving
- School of Biomolecular and Biomedical ScienceThe Conway InstituteUniversity College Dublin Dublin Ireland
| | - Jenni Harvey
- Division of NeuroscienceSchool of MedicineNinewells Hospital and Medical SchoolUniversity of Dundee Dundee United Kingdom
| |
Collapse
|
8
|
Wu XM, Qian C, Zhou YF, Yan YC, Luo QQ, Yung WH, Zhang FL, Jiang LR, Qian ZM, Ke Y. Bi-directionally protective communication between neurons and astrocytes under ischemia. Redox Biol 2017; 13:20-31. [PMID: 28551085 PMCID: PMC5447396 DOI: 10.1016/j.redox.2017.05.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 05/16/2017] [Accepted: 05/19/2017] [Indexed: 01/10/2023] Open
Abstract
The extensive existing knowledge on bi-directional communication between astrocytes and neurons led us to hypothesize that not only ischemia-preconditioned (IP) astrocytes can protect neurons but also IP neurons protect astrocytes from lethal ischemic injury. Here, we demonstrated for the first time that neurons have a significant role in protecting astrocytes from ischemic injury. The cultured medium from IP neurons (IPcNCM) induced a remarkable reduction in LDH and an increase in cell viability in ischemic astrocytes in vitro. Selective neuronal loss by kainic acid injection induced a significant increase in apoptotic astrocyte numbers in the brain of ischemic rats in vivo. Furthermore, TUNEL analysis, DNA ladder assay, and the measurements of ROS, GSH, pro- and anti-apoptotic factors, anti-oxidant enzymes and signal molecules in vitro and/or in vivo demonstrated that IP neurons protect astrocytes by an EPO-mediated inhibition of pro-apoptotic signals, activation of anti-apoptotic proteins via the P13K/ERK/STAT5 pathways and activation of anti-oxidant proteins via up-regulation of anti-oxidant enzymes. We demonstrated the existence of astro-protection by IP neurons under ischemia and proposed that the bi-directionally protective communications between cells might be a common activity in the brain or peripheral organs under most if not all pathological conditions.
Collapse
Affiliation(s)
- Xiao-Mei Wu
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China; Department of Biochemistry, Institute for Nautical Medicine, Nantong University, Nantong 226001, China
| | - Christopher Qian
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Yu-Fu Zhou
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China; Laboratory of Neuropharmacology, Fudan University School of Pharmacy, 826 Zhang Heng Road, Shanghai 201203, China
| | - Yick-Chun Yan
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Qian-Qian Luo
- Laboratory of Neuropharmacology, Fudan University School of Pharmacy, 826 Zhang Heng Road, Shanghai 201203, China; Department of Biochemistry, Institute for Nautical Medicine, Nantong University, Nantong 226001, China
| | - Wing-Ho Yung
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Fa-Li Zhang
- Laboratory of Neuropharmacology, Fudan University School of Pharmacy, 826 Zhang Heng Road, Shanghai 201203, China
| | - Li-Rong Jiang
- Laboratory of Neuropharmacology, Fudan University School of Pharmacy, 826 Zhang Heng Road, Shanghai 201203, China
| | - Zhong Ming Qian
- Laboratory of Neuropharmacology, Fudan University School of Pharmacy, 826 Zhang Heng Road, Shanghai 201203, China.
| | - Ya Ke
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| |
Collapse
|
9
|
Yu Y, Wu Y, Szabo A, Wang S, Yu S, Wang Q, Huang XF. Teasaponin improves leptin sensitivity in the prefrontal cortex of obese mice. Mol Nutr Food Res 2015; 59:2371-82. [DOI: 10.1002/mnfr.201500205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 08/11/2015] [Accepted: 08/13/2015] [Indexed: 12/23/2022]
Affiliation(s)
- Yinghua Yu
- School of Medicine; University of Wollongong and Illawarra Health and Medical Research Institute; NSW Australia
- Schizophrenia Research Institute (SRI); Sydney NSW Australia
| | - Yizhen Wu
- School of Medicine; University of Wollongong and Illawarra Health and Medical Research Institute; NSW Australia
| | - Alexander Szabo
- School of Medicine; University of Wollongong and Illawarra Health and Medical Research Institute; NSW Australia
- ANSTO Life Sciences; Australian Nuclear Science and Technology Organisation; Sydney Australia
| | - Sen Wang
- School of Medicine; University of Wollongong and Illawarra Health and Medical Research Institute; NSW Australia
- Department of Endocrinology and Metabolism; Affiliated Hospital of Liaoning University of Traditional Chinese Medicine; Shenyang Liaoning China
| | - Shijia Yu
- School of Medicine; University of Wollongong and Illawarra Health and Medical Research Institute; NSW Australia
- Department of Endocrinology and Metabolism; Affiliated Hospital of Liaoning University of Traditional Chinese Medicine; Shenyang Liaoning China
| | - Qing Wang
- Department of Neurology; The Third Affiliated Hospital of Sun Yat-Sen University; Guangzhou Guangdong P. R. China
| | - Xu-Feng Huang
- School of Medicine; University of Wollongong and Illawarra Health and Medical Research Institute; NSW Australia
- Schizophrenia Research Institute (SRI); Sydney NSW Australia
| |
Collapse
|
10
|
Hippocampal dynamics of synaptic NF-kappa B during inhibitory avoidance long-term memory consolidation in mice. Neuroscience 2015; 291:70-80. [DOI: 10.1016/j.neuroscience.2015.01.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 01/26/2015] [Accepted: 01/28/2015] [Indexed: 11/22/2022]
|
11
|
Gruol DL. IL-6 regulation of synaptic function in the CNS. Neuropharmacology 2014; 96:42-54. [PMID: 25445486 DOI: 10.1016/j.neuropharm.2014.10.023] [Citation(s) in RCA: 164] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 10/23/2014] [Accepted: 10/24/2014] [Indexed: 12/20/2022]
Abstract
A growing body of evidence supports a role for glial-produced neuroimmune factors, including the cytokine IL-6, in CNS physiology and pathology. CNS expression of IL-6 has been documented in the normal CNS at low levels and at elevated levels in several neurodegenerative or psychiatric disease states as well as in CNS infection and injury. The altered CNS function associated with these conditions raises the possibility that IL-6 has neuronal or synaptic actions. Studies in in vitro and in vivo models confirmed this possibility and showed that IL-6 can regulate a number of important neuronal and synaptic functions including synaptic transmission and synaptic plasticity, an important cellular mechanism of memory and learning. Behavioral studies in animal models provided further evidence of an important role for IL-6 as a regulator of CNS pathways that are critical to cognitive function. This review summarizes studies that have lead to our current state of knowledge. In spite of the progress that has been made, there is a need for a greater understanding of the physiological and pathophysiological actions of IL-6 in the CNS, the mechanisms underlying these actions, conditions that induce production of IL-6 in the CNS and therapeutic strategies that could ameliorate or promote IL-6 actions. This article is part of a Special Issue entitled 'Neuroimmunology and Synaptic Function'.
Collapse
Affiliation(s)
- Donna L Gruol
- Molecular and Cellular Neuroscience Department, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
| |
Collapse
|
12
|
Donzis EJ, Tronson NC. Modulation of learning and memory by cytokines: signaling mechanisms and long term consequences. Neurobiol Learn Mem 2014; 115:68-77. [PMID: 25151944 PMCID: PMC4250287 DOI: 10.1016/j.nlm.2014.08.008] [Citation(s) in RCA: 193] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 08/12/2014] [Accepted: 08/13/2014] [Indexed: 11/16/2022]
Abstract
This review describes the role of cytokines and their downstream signaling cascades on the modulation of learning and memory. Immune proteins are required for many key neural processes and dysregulation of these functions by systemic inflammation can result in impairments of memory that persist long after the resolution of inflammation. Recent research has demonstrated that manipulations of individual cytokines can modulate learning, memory, and synaptic plasticity. The many conflicting findings, however, have prevented a clear understanding of the precise role of cytokines in memory. Given the complexity of inflammatory signaling, understanding its modulatory role requires a shift in focus from single cytokines to a network of cytokine interactions and elucidation of the cytokine-dependent intracellular signaling cascades. Finally, we propose that whereas signal transduction and transcription may mediate short-term modulation of memory, long-lasting cellular and molecular mechanisms such as epigenetic modifications and altered neurogenesis may be required for the long lasting impact of inflammation on memory and cognition.
Collapse
Affiliation(s)
- Elissa J Donzis
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Natalie C Tronson
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
13
|
Gruol DL, Vo K, Bray JG. Increased astrocyte expression of IL-6 or CCL2 in transgenic mice alters levels of hippocampal and cerebellar proteins. Front Cell Neurosci 2014; 8:234. [PMID: 25177271 PMCID: PMC4132577 DOI: 10.3389/fncel.2014.00234] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 07/25/2014] [Indexed: 12/16/2022] Open
Abstract
Emerging research has identified that neuroimmune factors are produced by cells of the central nervous system (CNS) and play critical roles as regulators of CNS function, directors of neurodevelopment and responders to pathological processes. A wide range of neuroimmune factors are produced by CNS cells, primarily the glial cells, but the role of specific neuroimmune factors and their glial cell sources in CNS biology and pathology have yet to be fully elucidated. We have used transgenic mice that express elevated levels of a specific neuroimmune factor, the cytokine IL-6 or the chemokine CCL2, through genetic modification of astrocyte expression to identify targets of astrocyte produced IL-6 or CCL2 at the protein level. We found that in non-transgenic mice constitutive expression of IL-6 and CCL2 occurs in the two CNS regions studied, the hippocampus and cerebellum, as measured by ELISA. In the CCL2 transgenic mice elevated levels of CCL2 were evident in the hippocampus and cerebellum, whereas in the IL-6 transgenic mice, elevated levels of IL-6 were only evident in the cerebellum. Western blot analysis of the cellular and synaptic proteins in the hippocampus and cerebellum of the transgenic mice showed that the elevated levels of CCL2 or IL-6 resulted in alterations in the levels of specific proteins and that these actions differed for the two neuroimmune factors and for the two brain regions. These results are consistent with cell specific profiles of action for IL-6 and CCL2, actions that may be an important aspect of their respective roles in CNS physiology and pathophysiology.
Collapse
Affiliation(s)
- Donna L Gruol
- Molecular and Cellular Neuroscience Department, The Scripps Research Institute La Jolla, CA, USA
| | - Khanh Vo
- Molecular and Cellular Neuroscience Department, The Scripps Research Institute La Jolla, CA, USA
| | - Jennifer G Bray
- Department of Biology, University of Wisconsin-Stevens Point Stevens Point, WI, USA
| |
Collapse
|
14
|
Silvia A, Claudia M, Cristina B, Manuel SA, Rigillo G, Blom JMC, Nicoletta B, Bruno C, Carmine PM, Fabio T. Interleukin 18 activates MAPKs and STAT3 but not NF-κB in hippocampal HT-22 cells. Brain Behav Immun 2014; 40:85-94. [PMID: 24603356 PMCID: PMC6248908 DOI: 10.1016/j.bbi.2014.02.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 02/17/2014] [Accepted: 02/25/2014] [Indexed: 10/25/2022] Open
Abstract
Interleukin (IL)-18 is a cytokine previously demonstrated to participate in neuroinflammatory processes. Since the components of the IL-18 receptor complex are expressed in neurons throughout the brain, IL-18 is also believed to directly influence neuronal function. Here we tested this hypothesis on mouse hippocampal neurons by measuring the effects of IL-18 on three pathways previously shown to be regulated by this cytokine in non-neuronal cells: the MAPK pathways, p38 and ERK1/2 MAPKs, STAT3 and NF-κB. Experiments were carried out in vitro using the immortalized hippocampal neuronal line HT-22 or in vivo following i.c.v. injection with recombinant mouse IL-18. We showed that IL-18 did not activate NF-κB in HT-22 cells whereas it induced a rapid (within 15min) activation of the MAPK pathways. Moreover, we demonstrated that IL-18 treatment enhanced P-STAT3 (Tyr705)/STAT3 ratio in the nucleus of HT-22 cells after 30-60min of exposure. A similar increase in P-STAT3 (Tyr705)/STAT3 ratio was observed in the whole hippocampus one hour after i.c.v. injection. These data demonstrate that IL-18 can act directly on neuronal cells affecting the STAT3 pathway; therefore, possibly regulating the expression of specific genes within the hippocampus. This effect may help to explain some of the IL-18-induced effects on synaptic plasticity and functionality within the hippocampal system.
Collapse
Affiliation(s)
- Alboni Silvia
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Montanari Claudia
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Benatti Cristina
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Sanchez-Alavez Manuel
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Giovanna Rigillo
- Department of Medical and Surgical Sciences for Children and Adults, University of Modena and Reggio Emilia, Modena, Italy
| | - Joan MC Blom
- Department of Medical and Surgical Sciences for Children and Adults, University of Modena and Reggio Emilia, Modena, Italy
| | - Brunello Nicoletta
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Conti Bruno
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Pariante M. Carmine
- Stress, Psychiatry and Immunology Department of Psychological Medicine Institute of Psychiatry, Kings College London, London, UK
| | - Tascedda Fabio
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| |
Collapse
|
15
|
Salles A, Romano A, Freudenthal R. Synaptic NF-kappa B pathway in neuronal plasticity and memory. ACTA ACUST UNITED AC 2014; 108:256-62. [PMID: 24854662 DOI: 10.1016/j.jphysparis.2014.05.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 04/14/2014] [Accepted: 05/09/2014] [Indexed: 10/25/2022]
Abstract
Several transcription factors are present at the synapse, and among these are the Rel-NF-kappa B pathway components. NF-kappa B is a constitutive transcription factor, with a strong presence in the brain of which a considerable part is located in the neuropiles. This localization of the transcription factor, plus evidence pointing to different functions, is what gave place to two general hypotheses for synaptic NF-kappa B: (a) The transcription factor plays a role in the synapse to nucleus communication, and it is retrogradely transported from polarized localizations to regulate gene expression; (b) The transcription factor modulates the synaptic function locally. Evidence indicates that both mechanisms can operate simultaneously; here we will present different possibilities of these hypotheses that are supported by an increasing amount of data. We pay special attention to the local role of the transcription factor at the synapse, and based in the described evidence from different animal models, we propose several processes in which the transcription factor may change the synaptic strength.
Collapse
Affiliation(s)
- Angeles Salles
- Laboratorio de Neurobiología de la Memoria, FBMC, FCEyN, UBA, IFIBYNE, CONICET, 2°piso, pabellón II, Intendente Güiraldez 2160, Ciudad Universitaria, CP 1428, Ciudad Autónoma de Buenos Aires, Argentina.
| | - Arturo Romano
- Laboratorio de Neurobiología de la Memoria, FBMC, FCEyN, UBA, IFIBYNE, CONICET, 2°piso, pabellón II, Intendente Güiraldez 2160, Ciudad Universitaria, CP 1428, Ciudad Autónoma de Buenos Aires, Argentina.
| | - Ramiro Freudenthal
- Laboratorio de Neurobiología de la Memoria, FBMC, FCEyN, UBA, IFIBYNE, CONICET, 2°piso, pabellón II, Intendente Güiraldez 2160, Ciudad Universitaria, CP 1428, Ciudad Autónoma de Buenos Aires, Argentina.
| |
Collapse
|
16
|
Murase S, McKay RD. Neuronal activity-dependent STAT3 localization to nucleus is dependent on Tyr-705 and Ser-727 phosphorylation in rat hippocampal neurons. Eur J Neurosci 2013; 39:557-65. [PMID: 24199834 DOI: 10.1111/ejn.12412] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 09/27/2013] [Accepted: 10/07/2013] [Indexed: 01/02/2023]
Abstract
Signal transducer and activator of transcription 3 (STAT3) dramatically increases during the first post-natal week, and supports the survival of mature hippocampal neurons. Recently, we reported that chronic elevation of excitability leads to a loss of STAT3 signal, inducing vulnerability in neurons. The loss of STAT3 signal was due to impaired Erk1/2 activation. While overnight elevation of activity attenuated STAT3 signal, brief low-frequency stimuli, which induce long-term depression, have been shown to activate STAT3. Here we investigated how STAT3 responds to depolarization in mature neurons. A brief depolarization results in the transient activation of STAT3: it induces calcium influx through L-type voltage-gated calcium channels, which triggers activation of Src family kinases. Src family kinases are required for phosphorylation of STAT3 at Tyr-705 and Ser-727. PTyr-705 is Janus kinase (JAK)-dependent, while PSer-727 is dependent on Akt, the Ser/Thr kinase. Both PTyr-705 and PSer-727 are necessary for nuclear translocation of STAT3 in these neurons. Chronic elevation of spontaneous activity by an A-type potassium blocker, 4-aminopyridine (4-AP), also induced the transient phosphorylation of STAT3, which after 4 h fell to basal levels despite the presence of 4-AP. These results suggest that phasic and chronic neuronal activation induce distinct molecular pathways, resulting in opposing regulation of STAT3 signal.
Collapse
Affiliation(s)
- Sachiko Murase
- Laboratory of Molecular Biology, National Institute of Neurological Disorder and Stroke, National Institutes of Health, Bethesda, MD, USA
| | | |
Collapse
|
17
|
Shrivastava K, Llovera G, Recasens M, Chertoff M, Giménez-Llort L, Gonzalez B, Acarin L. Temporal expression of cytokines and signal transducer and activator of transcription factor 3 activation after neonatal hypoxia/ischemia in mice. Dev Neurosci 2013; 35:212-25. [PMID: 23571161 DOI: 10.1159/000348432] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 01/23/2013] [Indexed: 11/19/2022] Open
Abstract
Hypoxia/ischemia (HI) is a prevalent reason for neonatal brain injury with inflammation being an inevitable phenomenon following such injury; but there is a scarcity of data regarding the signaling pathway involved and the effector molecules. The signal transducer and activator of transcription factor 3 (STAT3) is known to modulate injury following imbalance between pro- and anti-inflammatory cytokines in peripheral and central nervous system injury making it a potential molecule for study. The current study investigates the temporal expression of interleukin (IL)-6, IL-1β, tumor necrosis factor-α, IL-1ra, IL-4, IL-10, IL-13 and phosphorylated STAT3 (pSTAT3) after carotid occlusion and hypoxia (8% O2, 55 min) in postnatal day 7 C57BL/6 mice from 3 h to 21 days after hypoxia. Protein array illustrated notable changes in cytokines expressed in both hemispheres in a time-dependent manner. The major pro-inflammatory cytokines showing immediate changes between ipsi- and contralateral hemispheres were IL-6 and IL-1β. The anti-inflammatory cytokines IL-4 and IL-13 demonstrated a delayed augmentation with no prominent differences between hemispheres, while IL-1ra showed two distinct peaks of expression spread over time. We also illustrate for the first time the spatiotemporal activation of pSTAT3 (Y705 phosphorylation) after a neonatal HI in mice brain. The main regions expressing pSTAT3 were the hippocampus and the corpus callosum. pSTAT3+ cells were mostly a subpopulation of activated astrocytes (GFAP+) and microglia/macrophages (F4/80+) seen only in the ipsilateral hemisphere at most time points studied (till 7 days after hypoxia). The highest expression of pSTAT3+ cells was observed to be around 24-48 h, where the presence of pSTAT3+ astrocytes and pSTAT3+ microglia/macrophages was seen by confocal micrographs. In conclusion, our study highlights a synchronized expression of some pro- and anti-inflammatory cytokines, especially in the long term not previously defined. It also points towards a significant role of STAT3 signaling following micro- and astrogliosis in the pathophysiology of neonatal HI-related brain injury. In the study, a shift from pro-inflammatory to anti-inflammatory cytokine profile was also noted as the injury progressed. We suggest that while designing efficient neuroprotective therapies using inflammatory molecules, the time of intervention and balance between the pro- and anti-inflammatory cytokines must be considered.
Collapse
Affiliation(s)
- K Shrivastava
- Department of Cell Biology, Physiology and Immunology, Universitat Autonoma Barcelona, Bellaterra, Spain.
| | | | | | | | | | | | | |
Collapse
|
18
|
Kim BK, Tran HYP, Shin EJ, Lee C, Chung YH, Jeong JH, Bach JH, Kim WK, Park DH, Saito K, Nabeshima T, Kim HC. IL-6 attenuates trimethyltin-induced cognitive dysfunction via activation of JAK2/STAT3, M1 mAChR and ERK signaling network. Cell Signal 2013; 25:1348-60. [PMID: 23499905 DOI: 10.1016/j.cellsig.2013.02.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 02/19/2013] [Indexed: 12/26/2022]
Abstract
We previously reported that interleukin (IL)-6 deficiency potentiates trimethyltin (TMT)-induced convulsive neurotoxicity. The purpose in this study was to investigate the molecular mechanism by which cytokines affect TMT-induced cognitive impairment. To accomplish this, we examined hippocampal changes in Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling in relation to cholinergic parameters after TMT treatment in mice genetically deficient in IL-6 (IL-6(-/-)), tumor necrosis factor-α (TNF-α(-/-)), or interferon-γ (IFN-γ(-/-)). The IL-6(-/-) mice were the most susceptible to TMT-induced cognitive dysfunction and exhibited significant decreases in JAK2/STAT3 signaling and M1 muscarinic acetylcholine receptor (mAChR) expression, as well as other cholinergic parameters, compared with wild-type (WT) animals. Recombinant IL-6 protein (rIL-6) significantly attenuated these impairments in TMT-treated IL-6(-/-) mice, whereas an IL-6 receptor antibody potentiated these impairments in TMT-treated WT animals. Inhibition of JAK2 with AG490 or inhibition of cholinergic signaling with the M1 mAChR antagonist dicyclomine counteracted the attenuating effects of rIL-6 on phosphorylated extracellular signal-regulated kinase (ERK) expression, or on cognitive impairment in TMT-treated IL-6(-/-) mice. However, neither AG490 nor dicyclomine significantly attenuated effects of rIL-6 on acetylcholinesterase values. Our results suggest that activation of JAK2/STAT3 signaling and upregulation of the M1 mAChR are essential components of IL-6-mediated memory improvement against TMT toxicity.
Collapse
Affiliation(s)
- Beom Keun Kim
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Nicolas CS, Peineau S, Amici M, Csaba Z, Fafouri A, Javalet C, Collett VJ, Hildebrandt L, Seaton G, Choi SL, Sim SE, Bradley C, Lee K, Zhuo M, Kaang BK, Gressens P, Dournaud P, Fitzjohn SM, Bortolotto ZA, Cho K, Collingridge GL. The Jak/STAT pathway is involved in synaptic plasticity. Neuron 2012; 73:374-90. [PMID: 22284190 PMCID: PMC3268861 DOI: 10.1016/j.neuron.2011.11.024] [Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2011] [Indexed: 12/15/2022]
Abstract
The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway is involved in many cellular processes, including cell growth and differentiation, immune functions and cancer. It is activated by various cytokines, growth factors, and protein tyrosine kinases (PTKs) and regulates the transcription of many genes. Of the four JAK isoforms and seven STAT isoforms known, JAK2 and STAT3 are highly expressed in the brain where they are present in the postsynaptic density (PSD). Here, we demonstrate a new neuronal function for the JAK/STAT pathway. Using a variety of complementary approaches, we show that the JAK/STAT pathway plays an essential role in the induction of NMDA-receptor dependent long-term depression (NMDAR-LTD) in the hippocampus. Therefore, in addition to established roles in cytokine signaling, the JAK/STAT pathway is involved in synaptic plasticity in the brain.
Collapse
Affiliation(s)
- Céline S Nicolas
- MRC Centre for Synaptic Plasticity, School of Physiology and Pharmacology, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Moore DL, Goldberg JL. Multiple transcription factor families regulate axon growth and regeneration. Dev Neurobiol 2012; 71:1186-211. [PMID: 21674813 DOI: 10.1002/dneu.20934] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Understanding axon regenerative failure remains a major goal in neuroscience, and reversing this failure remains a major goal for clinical neurology. Although an inhibitory central nervous system environment clearly plays a role, focus on molecular pathways within neurons has begun to yield fruitful insights. Initial steps forward investigated the receptors and signaling pathways immediately downstream of environmental cues, but recent work has also shed light on transcriptional control mechanisms that regulate intrinsic axon growth ability, presumably through whole cassettes of gene target regulation. Here we will discuss transcription factors that regulate neurite growth in vitro and in vivo, including p53, SnoN, E47, cAMP-responsive element binding protein (CREB), signal transducer and activator of transcription 3 (STAT3), nuclear factor of activated T cell (NFAT), c-Jun activating transcription factor 3 (ATF3), sex determining region Ybox containing gene 11 (Sox11), nuclear factor κ-light chain enhancer of activated B cells (NFκB), and Krüppel-like factors (KLFs). Revealing the similarities and differences among the functions of these transcription factors may further our understanding of the mechanisms of transcriptional regulation in axon growth and regeneration.
Collapse
Affiliation(s)
- Darcie L Moore
- Bascom Palmer Eye Institute and the Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Florida, USA
| | | |
Collapse
|
21
|
Burgos-Ramos E, Chowen JA, Argente J, Barrios V. Regional and temporal differences in leptin signaling in rat brain. Gen Comp Endocrinol 2010; 167:143-52. [PMID: 20138175 DOI: 10.1016/j.ygcen.2010.01.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 12/28/2009] [Accepted: 01/31/2010] [Indexed: 11/29/2022]
Abstract
Leptin regulates energy homeostasis through activation of different hypothalamic pathways. Evidence indicates that leptin is a pleiotropic hormone that acts on many brain areas, altering food intake, metabolism, and locomotion, among other functions. Because short-term effects of leptin infusion and intracellular pathways in other brain areas involved in food regulation have not been thoroughly analysed, we have studied the acute effect of intracerebroventricular leptin administration on the levels of the long form of leptin receptor (Ob-Rb), as well as on activation of Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3), protein kinase B (Akt), extracellular regulated kinases (ERKs) and levels of suppressor of cytokine signaling-3 (SOCS3) in the hypothalamus, hippocampus, frontal cortex and cerebellum of adult male Wistar rats at 15min, 1 and 6h. The levels of Ob-Rb increased at 6h in hypothalamus only. Leptin activated the JAK2/STAT3 pathway in all areas, although in a temporally specific pattern. In contrast, this hormone decreased Akt activation in hypothalamus, hippocampus and cerebellum and ERK activation in frontal cortex, while it increased ERK activation in hypothalamus and hippocampus. These differences in modulation of Ob-Rb levels and signaling indicate that the rapid effects of leptin in non-hypothalamic areas are mediated, at least in part, through the intracellular pathways involved in hypothalamic energy balance, but in a temporally specific manner.
Collapse
Affiliation(s)
- Emma Burgos-Ramos
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Universidad Autónoma de Madrid, Madrid E-28009, Spain
| | | | | | | |
Collapse
|
22
|
Chiba T, Yamada M, Aiso S. Targeting the JAK2/STAT3 axis in Alzheimer's disease. Expert Opin Ther Targets 2009; 13:1155-67. [PMID: 19663649 DOI: 10.1517/14728220903213426] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Amyloid beta (Abeta) has long been implicated in the pathogenesis of Alzheimer's disease (AD). Little is known, however, about the intracellular events in neurons which lead to memory loss related to AD. Focusing on the fact that an AD-specific neuroprotective peptide named humanin (HN) inhibits AD-related neurotoxicity by activating the JAK2/STAT3 signaling axis, we recently found that age- and disease-dependent deterioration in the JAK2/STAT3 axis plays a critical role in the pathogenesis of AD. OBJECTIVE/METHODS Here we summarize the neuroprotective effect of HN and its derivative, named colivelin (CLN), and also review the roles of the JAK2/STAT3 axis in memory impairment related to AD. RESULTS/CONCLUSIONS The JAK2/STAT3 axis is a major transducer of HN-mediated neuroprotective activity. Abeta-dependent inactivation of the JAK2/STAT3 axis in hippocampal neurons causes cholinergic dysfunction via pre- and post-synaptic mechanisms, which leads to memory impairment related to AD. This provides not only a novel pathological hallmark of AD but also a novel target in AD therapy.
Collapse
Affiliation(s)
- Tomohiro Chiba
- Keio University School of Medicine, Department of Anatomy, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
| | | | | |
Collapse
|
23
|
Ito H, Atsuzawa K, Morishita R, Usuda N, Sudo K, Iwamoto I, Mizutani K, Katoh-Semba R, Nozawa Y, Asano T, Nagata KI. Sept8 controls the binding of vesicle-associated membrane protein 2 to synaptophysin. J Neurochem 2009; 108:867-80. [PMID: 19196426 DOI: 10.1111/j.1471-4159.2008.05849.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Septins, a conserved family of GTP/GDP-binding proteins, are present in organisms as diverse as yeast and mammals. We analyzed the distribution of five septins, Sept6, Sept7, Sept8, Sept9 and Sept11, in various rat tissues by western blot analyses and found all septins to be expressed in brain. We also examined the developmental changes of expression of these septins in the rat brain and found that the level of Sept8 increased during post-natal development. Morphological analyses revealed that Sept8 is enriched at pre-synapses. Using yeast two-hybrid screening, we identified vesicle-associated membrane protein 2 (VAMP2), a soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE), as an interacting protein for Sept8. Synaptophysin is reported to associate with and recruit VAMP2 to synaptic vesicles and dissociate prior to forming the SNARE complex consisting of VAMP2, syntaxin and synaptosome-associated protein of 25 kDa. We showed that Sept8 suppresses the interaction between VAMP2 and synaptophysin through binding to VAMP2. In addition, we found that Sept8 forms a complex with syntaxin1A, and the Sept8-VAMP2 interaction is disrupted by synaptosome-associated protein of 25 kDa. These results suggest that Sept8 may participate in the process of the SNARE complex formation and subsequent neurotransmitter release.
Collapse
Affiliation(s)
- Hidenori Ito
- Institute for Developmental Research, Aichi Human Service Center, Kasugai, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Dziennis S, Alkayed NJ. Role of signal transducer and activator of transcription 3 in neuronal survival and regeneration. Rev Neurosci 2009; 19:341-61. [PMID: 19145989 DOI: 10.1515/revneuro.2008.19.4-5.341] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Signal Transducers and Activators of Transcription (STATs) comprise a family of transcription factors that mediate a wide variety of biological functions in the central and peripheral nervous systems. Injury to neural tissue induces STAT activation, and STATs are increasingly recognized for their role in neuronal survival. In this review, we discuss the role of STAT3 during neural development and following ischemic and traumatic injury in brain, spinal cord and peripheral nerves. We focus on STAT3 because of the expanding body of literature that investigates protective and regenerative effects of growth factors, hormones and cytokines that use STAT3 to mediate their effect, in part through transcriptional upregulation of neuroprotective and neurotrophic genes. Defining the endogenous molecular mechanisms that lead to neuroprotection by STAT3 after injury might identify novel therapeutic targets against acute neural tissue damage as well as chronic neurodegenerative disorders.
Collapse
Affiliation(s)
- Suzan Dziennis
- Department of Anesthesiology & Peri-Operative Medicine, Oregon Health & Science University, Portland, OR 97239-3098, USA
| | | |
Collapse
|
25
|
Ito H, Usuda N, Atsuzawa K, Iwamoto I, Sudo K, Katoh-Semba R, Mizutani K, Morishita R, Deguchi T, Nozawa Y, Asano T, Nagata KI. Phosphorylation by extracellular signal-regulated kinase of a multidomain adaptor protein, vinexin, at synapses. J Neurochem 2007; 100:545-54. [PMID: 17241162 DOI: 10.1111/j.1471-4159.2006.04222.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Vinexin is an adaptor protein that is supposed to play pivotal roles in cell adhesion, cytoskeletal organization and signaling. At least three splice variants, vinexinalpha, beta and gamma, have so far been reported. In spite of the possible importance of vinexin, the properties and functions of vinexin in neuronal cells are almost unknown. Here we show that vinexin isoforms are expressed in rat brain in a developmental stage-dependent manner, and that vinexinalpha is relatively abundant in the telencephalon regions of the adult rat brain. An immunohistochemical study showed the localization of vinexinalpha in neurons and glia in the rat brain. In primary cultured rat hippocampal neurons, vinexin was found to be present at synapses and filopodia in growth cones by immunofluorescent analyses. Biochemical fractionation revealed the distribution of vinexin in synaptosomes. Nerve terminal localization of vinexin was confirmed by electron microscopy. Vinexinbeta is reported to be phosphorylated by extracellular signal-regulated kinase (ERK) at Ser189, which is equivalent to Ser593 of vinexinalpha. We thus constructed a site- and phosphorylation state-specific antibody to monitor the ERK-mediated phosphorylation of vinexin. In immunofluorescent analyses, the phosphorylation was observed at synapses formed among cultured rat hippocampal neurons and it was reduced by treatment of the cells with PD98059. In an immunoelectron microscopic examination, the phosphorylation signal was mainly detected on the postsynaptic side of synapses in the rat hippocampal neurons. As active ERK was co-localized with vinexin in synapses, the ERK signal is likely to be involved in the regulation of vinexin-dependent cellular processes in synapses. On the other hand, the phosphorylation was hardly detected in neurons cultured for 3 days, suggesting the presence of a yet unidentified regulatory mechanism of vinexin at the growth cone.
Collapse
Affiliation(s)
- Hidenori Ito
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Human Service Center, Kasugai, japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Suzuki T, Tian QB, Kuromitsu J, Kawai T, Endo S. Characterization of mRNA species that are associated with postsynaptic density fraction by gene chip microarray analysis. Neurosci Res 2006; 57:61-85. [PMID: 17049655 DOI: 10.1016/j.neures.2006.09.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2006] [Revised: 09/12/2006] [Accepted: 09/14/2006] [Indexed: 11/18/2022]
Abstract
We previously reported the partial identification by random sequencing of mRNA species that are associated with the postsynaptic density (PSD) fraction prepared from the rat forebrain [Tian et al., 1999. Mol. Brain Res. 72, 147-157]. We report here further characterization by gene chip analysis of the PSD fraction-associated mRNAs, which were prepared in the presence of RNase inhibitor. We found that mRNAs encoding various postsynaptic proteins, such as channels, receptors for neurotransmitters and neuromodulators, proteins involved in signaling, scaffold and adaptor proteins and cytoskeletal proteins, were highly concentrated in the PSD fraction, whereas those encoding housekeeping proteins, such as enzymes in the glycolytic pathway, were not. We extracted approximately 1900 mRNA species that were highly concentrated in the PSD fraction. mRNAs related to certain neuronal diseases were also enriched in the PSD fraction. We also constructed a cDNA library using the PSD fraction-associated mRNAs as templates, and identified 1152 randomly selected clones by sequencing. Our data suggested that the PSD fraction-associated mRNAs are a very useful resource, in which a number of as yet uncharacterized mRNAs are concentrated. Identification and functional characterization of them are essential for complete understanding of synaptic function.
Collapse
Affiliation(s)
- Tatsuo Suzuki
- Department of Neuroplasticity, Institute on Aging and Adaptation, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
| | | | | | | | | |
Collapse
|
27
|
Tian QB, Suzuki T, Yamauchi T, Sakagami H, Yoshimura Y, Miyazawa S, Nakayama K, Saitoh F, Zhang JP, Lu Y, Kondo H, Endo S. Interaction of LDL receptor-related protein 4 (LRP4) with postsynaptic scaffold proteins via its C-terminal PDZ domain-binding motif, and its regulation by Ca/calmodulin-dependent protein kinase II. Eur J Neurosci 2006; 23:2864-76. [PMID: 16819975 DOI: 10.1111/j.1460-9568.2006.04846.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We cloned here a full-length cDNA of Dem26[Tian et al. (1999)Mol. Brain Res., 72, 147-157], a member of the low-density lipoprotein (LDL) receptor gene family from the rat brain. We originally named the corresponding protein synaptic LDL receptor-related protein (synLRP) [Tian et al. (2002) Soc. Neurosci. Abstr., 28, 405] and have renamed it LRP4 to accord it systematic nomenclature (GenBank(TM) accession no. AB073317). LRP4 protein interacted with postsynaptic scaffold proteins such as postsynaptic density (PSD)-95 via its C-terminal tail sequence, and associated with N-methyl-D-aspartate (NMDA)-type glutamate receptor subunit. The mRNA of LRP4 was localized to dendrites, as well as somas, of neuronal cells, and the full-length protein of 250 kDa was highly concentrated in the brain and localized to various subcellular compartments in the brain, including synaptic fractions. Immunocytochemical study using cultured cortical neurons suggested surface localization in the neuronal cells both in somas and dendrites. Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) phosphorylated the C-terminal cytoplasmic region of LRP4 at Ser1887 and Ser1900, and the phosphorylation at the latter site suppressed the interaction of the protein with PSD-95 and synapse-associated protein 97 (SAP97). These findings suggest a postsynaptic role for LRP4, a putative endocytic multiligand receptor, and a mechanism in which CaMKII regulates PDZ-dependent protein-protein interactions and receptor dynamics.
Collapse
Affiliation(s)
- Qing-Bao Tian
- Department of Neuroplasticity, Institute on Ageing and Adaptation, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Cooper ST, Hanson IM. A screen for proteins that interact with PAX6: C-terminal mutations disrupt interaction with HOMER3, DNCL1 and TRIM11. BMC Genet 2005; 6:43. [PMID: 16098226 PMCID: PMC1208879 DOI: 10.1186/1471-2156-6-43] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Accepted: 08/12/2005] [Indexed: 11/10/2022] Open
Abstract
Background The PAX6 protein is a transcriptional regulator with a key role in ocular and neurological development. Individuals with heterozygous loss-of-function mutations in the PAX6 gene have malformations of the eye and brain. Little is known about the interactions of PAX6 with other proteins, so we carried out a systematic screen for proteins that interact with PAX6. Results We used bioinformatics techniques to characterise a highly conserved peptide at the C-terminus of the PAX6 protein. Yeast two-hybrid library screens were then carried out to identify brain-expressed proteins that interact with the C-terminal peptide and with the entire PAX6 proline-serine-threonine-rich domain. Three novel PAX6-interacting proteins were identified: the post-synaptic density (PSD) protein HOMER3, the dynein subunit DNCL1, and the tripartite motif protein TRIM11. Three C-terminal PAX6 mutations, previously identified in patients with eye malformations, all reduced or abolished the interactions. Conclusion Our preliminary data suggest that PAX6 interacts with HOMER3, DNCL1 and TRIM11. We propose that the interaction of PAX6 with HOMER3 and DNCL1 is a mechanism by which synaptic activation could lead to changes in neuronal transcriptional activity, and that some of the neural anomalies in patients with PAX6 mutations could be explained by impaired protein-protein interactions.
Collapse
Affiliation(s)
- Simon T Cooper
- University of Edinburgh, School of Molecular and Clinical Medicine, Medical Sciences (Medical Genetics), Molecular Medicine Centre, Western General Hospital, Crewe Road Edinburgh EH4 2XU
| | - Isabel M Hanson
- University of Edinburgh, School of Molecular and Clinical Medicine, Medical Sciences (Medical Genetics), Molecular Medicine Centre, Western General Hospital, Crewe Road Edinburgh EH4 2XU
| |
Collapse
|
29
|
Wang X, Tian QB, Okano A, Sakagami H, Moon IS, Kondo H, Endo S, Suzuki T. BAALC 1-6-8 protein is targeted to postsynaptic lipid rafts by its N-terminal myristoylation and palmitoylation, and interacts with alpha, but not beta, subunit of Ca/calmodulin-dependent protein kinase II. J Neurochem 2005; 92:647-59. [PMID: 15659234 DOI: 10.1111/j.1471-4159.2004.02902.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We cloned a rat BAALC 1-6-8 isoform cDNA (GenBank Accession No. AB073318) that encoded a 22-kDa protein, and identified endogenous BAALC 1-6-8 protein in the brain. The gene was expressed widely in the frontal part of the brain, and the protein was localized to the synaptic sites and was increased in parallel with synaptogenesis. The protein interacted with the alpha, but not beta, subunit of Ca(2+)/calmodulin-dependent protein kinase II (CaMKIIalpha). The interaction occurred between the N-terminal 35-amino-acid region of BAALC 1-6-8 protein and the C-terminal end of the regulatory domain of CaMKIIalpha, which contains alpha isoform-specific sequence. Thus, the interaction may be CaMKIIalpha-specific. We also found that BAALC 1-6-8 protein, as well as CaMKIIalpha, was localized to lipid rafts and that both myristoylation and palmitoylation of BAALC 1-6-8 N-terminal portion were required for targeting of the protein into lipid rafts. These findings suggest that BAALC 1-6-8 protein play a synaptic role at the postsynaptic lipid raft possibly through interaction with CaMKIIalpha.
Collapse
Affiliation(s)
- Xin Wang
- Department of Neuroplasticity, Institute on Aging and Adaptation, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Suzuki T, Li W, Zhang JP, Tian QB, Sakagami H, Usuda N, Usada N, Kondo H, Fujii T, Endo S. A novel scaffold protein, TANC, possibly a rat homolog of Drosophila rolling pebbles (rols), forms a multiprotein complex with various postsynaptic density proteins. Eur J Neurosci 2005; 21:339-50. [PMID: 15673434 DOI: 10.1111/j.1460-9568.2005.03856.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We cloned from the rat brain a novel gene, tanc (GenBank Accession No. AB098072), which encoded a protein containing three tetratricopeptide repeats (TPRs), ten ankyrin repeats and a coiled-coil region, and is possibly a rat homolog of Drosophila rolling pebbles (rols). The tanc gene was expressed widely in the adult rat brain. Subcellular distribution, immunohistochemical study of the brain and immunocytochemical studies of cultured neuronal cells indicated the postsynaptic localization of TANC protein of 200 kDa. Pull-down experiments showed that TANC protein bound PSD-95, SAP97, and Homer via its C-terminal PDZ-binding motif, -ESNV, and fodrin via both its ankyrin repeats and the TPRs together with the coiled-coil domain. TANC also bound the alpha subunit of Ca2+/calmodulin-dependent protein kinase II. An immunoprecipitation study showed TANC association with various postsynaptic proteins, including guanylate kinase-associated protein (GKAP), alpha-internexin, and N-methyl-D-aspartate (NMDA)-type glutamate receptor 2B and AMPA-type glutamate receptor (GluR1) subunits. These results suggest that TANC protein may work as a postsynaptic scaffold component by forming a multiprotein complex with various postsynaptic density proteins.
Collapse
MESH Headings
- Age Factors
- Amino Acid Sequence
- Animals
- Animals, Newborn
- Ankyrin Repeat/genetics
- Blotting, Northern
- Blotting, Western/methods
- Brain/cytology
- Brain/metabolism
- Cells, Cultured
- Cloning, Molecular/methods
- Crotalid Venoms/genetics
- Crotalid Venoms/metabolism
- Disks Large Homolog 4 Protein
- Drosophila
- Drosophila Proteins/chemistry
- Drosophila Proteins/genetics
- Gene Expression Regulation/physiology
- Humans
- Immunohistochemistry/methods
- Immunoprecipitation/methods
- In Situ Hybridization/methods
- Intracellular Signaling Peptides and Proteins
- Lectins, C-Type/genetics
- Lectins, C-Type/metabolism
- Membrane Proteins/chemistry
- Membrane Proteins/genetics
- Molecular Sequence Data
- Multiprotein Complexes/metabolism
- Muscle Proteins/chemistry
- Muscle Proteins/genetics
- Nerve Tissue Proteins/chemistry
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Neurons/metabolism
- Protein Binding/physiology
- Protein Structure, Tertiary
- RNA, Messenger/biosynthesis
- Rats
- Receptors, AMPA/metabolism
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Subcellular Fractions/metabolism
Collapse
Affiliation(s)
- Tatsuo Suzuki
- Department of Neuroplasticity, Institute on Ageing and Adaptation, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Jing-Ping Z, Tian QB, Sakagami H, Kondo H, Endo S, Suzuki T. p55 protein is a member of PSD scaffold proteins in the rat brain and interacts with various PSD proteins. ACTA ACUST UNITED AC 2005; 135:204-16. [PMID: 15857683 DOI: 10.1016/j.molbrainres.2004.12.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2004] [Revised: 12/12/2004] [Accepted: 12/20/2004] [Indexed: 10/25/2022]
Abstract
p55 is a membrane-associated guanylate kinase (MAGuK) family member that consists of a single PDZ followed by SH3, HOOK and guanylate kinase (GuK or GK) domains. We investigated rat p55 (r-p55) in the brain. r-p55 mRNA was expressed widely in various tissues and in various regions of the brain. r-p55 protein was also expressed widely in various rat tissues, including brain and erythrocytes. The protein was enriched in the synaptic plasma membrane and postsynaptic density (PSD) fractions of the forebrain. An immunocytochemical study using cultured cortical neurons suggested postsynaptic localization of r-p55 protein. Pull-down assay showed that r-p55 protein interacted with r-p55 itself and various PSD proteins, such as PSD-95, SAP97, GKAP, CASK, GRIP, neuroligin, cadherin, tubulin, actin, alpha-internexin, neurofilament-L and Ca(2+)/calmodulin-dependent protein kinase II, through its PDZ, SH3, HOOK or GK domains. The interaction with PSD-95 was found to occur between the PDZ domains of PSD-95 and the HOOK and GK domains of r-p55 protein. These findings, together with the presence of r-p55 puncta in a period of early synaptogenesis, suggest that r-p55 protein functions as one of postsynaptic scaffold component in an early stage of synaptogenesis in the brain. r-p55 protein may form a basic structure, which interlinks diverse functional molecules of the PSD necessary for postsynaptic signaling and synaptic adhesion.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Animals, Newborn
- Antibody Specificity
- Blotting, Northern
- Blotting, Western/methods
- Brain/cytology
- Brain/embryology
- Brain/metabolism
- Calcium-Calmodulin-Dependent Protein Kinases/metabolism
- Cells, Cultured
- Cloning, Molecular/methods
- DNA, Complementary/metabolism
- Disks Large Homolog 4 Protein
- Electrophoretic Mobility Shift Assay/methods
- Embryo, Mammalian
- Fluorescent Antibody Technique/methods
- Gene Expression Regulation, Developmental/physiology
- Guanylate Kinases
- Immunoprecipitation/methods
- In Situ Hybridization/methods
- Intracellular Signaling Peptides and Proteins
- Male
- Membrane Proteins
- Multiprotein Complexes/metabolism
- Nerve Tissue Proteins/classification
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/immunology
- Nerve Tissue Proteins/metabolism
- Neurons/metabolism
- Protein Structure, Tertiary/physiology
- RNA, Messenger/biosynthesis
- Rats
- Rats, Wistar
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Signal Transduction
- Subcellular Fractions/metabolism
- Synaptophysin/metabolism
- Time Factors
Collapse
Affiliation(s)
- Zhang Jing-Ping
- Department of Neuroplasticity, Institute on Aging and Adaptation, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan
| | | | | | | | | | | |
Collapse
|
32
|
Inaba Y, Tian QB, Okano A, Zhang JP, Sakagami H, Miyazawa S, Li W, Komiyama A, Inokuchi K, Kondo H, Suzuki T. Brain-specific potential guanine nucleotide exchange factor for Arf, synArfGEF (Po), is localized to postsynaptic density. J Neurochem 2004; 89:1347-57. [PMID: 15189337 DOI: 10.1111/j.1471-4159.2004.02440.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: 12/11/2022]
Abstract
We cloned from a rat brain cDNA library a novel cDNA and named it a potential synaptic guanine nucleotide exchange factor (GEF) for Arf (synArfGEF (Po)) (GenBank Accession no. AB057643) based on its domain structure and localization. The cloned gene was 7410 bases long with a 3585-bp coding sequence encoding a protein of 1194 amino acids. The deduced protein contained a coiled-coil structure in the N-terminal portion followed by Sec7 and Plekstrin homology (PH) domains. Thus, the protein was a member of the Sec7 family of proteins, GEFs. Conservation of the ADP-ribosylation factor (Arf)-binding sequence suggested that the protein was a GEF for Arf. The gene was expressed specifically in the brain, where it exhibited region-specific expression. The protein was highly enriched in the postsynaptic density (PSD) fraction prepared from the rat forebrain. Uniquely, the protein interacted with PSD-95, SAP97 and Homer/Vesl 1/PSD-Zip45 via its C-terminal PDZ-binding motif and co-localized with these proteins in cultured cortical neurons. These results supported its localization in the PSD. The postsynaptic localization was also supported by immunohistochemical examination of the rat brain. The mRNA for the synArfGEF was also localized to dendrites, as well as somas, of neuronal cells. Thus, both the mRNA and the protein were localized in the postsynaptic compartments. These results suggest a postsynaptic role of synArfGEF in the brain.
Collapse
Affiliation(s)
- Yuji Inaba
- Department of Neuroplasticity, Research Institute on Aging and Adaptation, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Saitoh F, Tian QB, Okano A, Sakagami H, Kondo H, Suzuki T. NIDD, a Novel DHHC-containing Protein, Targets Neuronal Nitric-oxide Synthase (nNOS) to the Synaptic Membrane through a PDZ-dependent Interaction and Regulates nNOS Activity. J Biol Chem 2004; 279:29461-8. [PMID: 15105416 DOI: 10.1074/jbc.m401471200] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Targeting of neuronal nitric-oxide synthase (nNOS) to appropriate sites in a cell is mediated by interactions with its PDZ domain and plays an important role in specifying the sites of reaction of nitric oxide (NO) in the central nervous system. Here we report the identification and characterization of a novel nNOS-interacting DHHC domain-containing protein with dendritic mRNA (NIDD) (GenBank accession number AB098078), which increases nNOS enzyme activity by targeting the nNOS to the synaptic plasma membrane in a PDZ domain-dependent manner. The deduced NIDD protein consisted of 392 amino acid residues and possessed five transmembrane segments, a zinc finger DHHC domain, and a PDZ-binding motif (-EDIV) at its C-terminal tail. In vitro pull-down assays suggested that the C-terminal tail region of NIDD specifically interacted with the PDZ domain of nNOS. The PDZ dependence was confirmed by an experiment using a deletion mutant, and the interaction was further confirmed by co-sedimentation assays using COS-7 cells transfected with NIDD and nNOS. Both NIDD and nNOS were enriched in synaptosome and synaptic plasma membrane fractions and were present in the lipid raft and postsynaptic density fractions in the rat brain. Co-localization of these proteins was also observed by double staining of the proteins in cultured cortical neurons. Thus, NIDD and nNOS were co-localized in the brain, although the colocalizing regions were restricted, as indicated by the distribution of their mRNA expression. Most important, co-transfection of NIDD and nNOS increased NO-producing nNOS activity. These results suggested that NIDD plays an important role in the regulation of the NO signaling pathway at postsynaptic sites through targeting of nNOS to the postsynaptic membrane.
Collapse
Affiliation(s)
- Fuminori Saitoh
- Department of Neuroplasticity Institute on Aging and Adaptation, Shinshu University Graduate School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan
| | | | | | | | | | | |
Collapse
|
34
|
Abstract
The Eph receptors are a large family of receptor tyrosine kinases with important roles in the establishment of neuronal and vascular networks during embryonic development. The functions of Eph receptors in the adult brain have only recently been investigated, and the results are forcing us to amend the conventional view that these molecules function predominantly in a developmental context. This review summarizes this rapidly expanding new area of research, which has shown that the Eph receptors regulate the structure and physiological function of excitatory synapses through multiple mechanisms, and might thus play a significant role in higher brain functions.
Collapse
Affiliation(s)
- Yu Yamaguchi
- Developmental Neurobiology Program, The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, California 92037, USA.
| | | |
Collapse
|
35
|
Lai KO, Chen Y, Po HM, Lok KC, Gong K, Ip NY. Identification of the Jak/Stat Proteins as Novel Downstream Targets of EphA4 Signaling in Muscle. J Biol Chem 2004; 279:13383-92. [PMID: 14729671 DOI: 10.1074/jbc.m313356200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Eph receptors and their cognate ligands ephrins are important players in axon guidance and neural patterning during development of the nervous system. Much of our knowledge about the signal transduction pathways triggered by Eph receptors has been related to the modulation of actin cytoskeleton, which is fundamental in mediating the cellular responses in growth cone navigation, cell adhesion, and cell migration. In contrast, little was known about whether long term activation of Eph receptor would regulate gene expression. Here we report a novel signaling pathway of EphA4, which involves activation of the tyrosine kinase Jak2 and the transcriptional activator Stat3. Transfection of COS7 cells with EphA4, but not the kinase-dead mutant, induced tyrosine phosphorylation of Jak2, Stat1, and Stat3. Treatment of cultured C2C12 myotubes with ephrin-A1 also induced tyrosine phosphorylation of Stat3, which was abolished by the Jak2 inhibitor AG490. Moreover, Jak2 was co-immunoprecipitated with EphA4 in muscle, and both proteins were concentrated at the neuromuscular junction (NMJ) of adult muscle. By using microarray analysis, we have identified acetylcholinesterase, the critical enzyme that hydrolyzed the neurotransmitter acetylcholine at the NMJ, as a downstream target gene of the Jak/Stat pathway in muscle. More importantly, ephrin-A1 increased the expression of acetylcholinesterase protein in C2C12 myotubes, which was abolished by AG490. In contrast, ephrin-A1 reduced the expression of fibronectin mRNA in C2C12 myotubes independently of Jak2. Finally, the expression level of acetylcholinesterase in limb muscle of EphA4 null mice was significantly reduced compared with the wild-type control. Taken together, these results have identified Jak/Stat proteins as the novel downstream targets of EphA4 signaling. In addition, the present study provides the first demonstration of a potential function of Eph receptors and Jak/Stat proteins at the NMJ.
Collapse
Affiliation(s)
- Kwok-On Lai
- Department of Biochemistry, Molecular Neuroscience Center and Biotechnology Research Institute, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, People's Republic of China
| | | | | | | | | | | |
Collapse
|
36
|
Rosell DR, Akama KT, Nacher J, McEwen BS. Differential expression of suppressors of cytokine signaling-1, -2, and -3 in the rat hippocampus after seizure: implications for neuromodulation by gp130 cytokines. Neuroscience 2004; 122:349-58. [PMID: 14614901 DOI: 10.1016/s0306-4522(03)00594-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Numerous studies have investigated the expression of various cytokine families in the CNS after brain injury. The gp130 or interleukin (IL)-6-type cytokines have received a great deal of focus, and it is clear that they exhibit an acute and robust upregulation in various brain injury models. We are interested to determine, however, whether endogenously expressed cytokines in the CNS act in a direct neuromodulatory manner. In an accompanying study, we examined the expression of five gp130 cytokines and their receptors in the lithium-pilocarpine model of status epilepticus. We follow up that study here by trying to determine if gp130 signal transduction occurs in hippocampal principal neurons after seizure. Therefore, using the expression of suppressors of cytokine signaling (SOCS)-1 and -3 as indices of gp130 signal transduction, we performed a detailed in situ hybridization seizure time-course study in the adult rat hippocampus. For comparison, we also examined SOCS-2, which is involved in insulin-like growth factor signaling. We found that while SOCS-1 and -3 were faintly expressed under basal conditions, only SOCS-3 exhibited a rapid, robust, and transient induction. This occurred first in non-principal cells, which appeared to be glial, peaking at approximately 12 h post-seizure. Subsequently, a robust induction of SOCS-3 occurred in pyramidal and granule neurons, peaking at approximately 24 h. SOCS-2 displayed a relatively higher level of basal expression, particularly in CA3, and a mild and transient downregulation by 24 h. These findings corroborate the hypothesis that seizure-induced gp130 cytokines play a direct neuromodulatory role in the hippocampus. Since in our previous study we did not detect cytokine receptor expression in non-principal cells, it is unclear what elicits SOCS-3 expression in this population.
Collapse
Affiliation(s)
- D R Rosell
- Laboratory of Neuroendocrinology, The Rockefeller University, 1230 York Avenue, Box 165, New York, NY 10021, USA.
| | | | | | | |
Collapse
|
37
|
Tian QB, Okano A, Nakayama K, Miyazawa S, Endo S, Suzuki T. A novel ubiquitin-specific protease, synUSP, is localized at the post-synaptic density and post-synaptic lipid raft. J Neurochem 2003; 87:665-75. [PMID: 14535949 DOI: 10.1046/j.1471-4159.2003.02024.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Recent reports suggest an important role for protein ubiquitination in synaptic plasticity. We cloned, from the rat brain, a novel gene that encoded an ubiquitin-specific protease (USP), and termed this protein synaptic ubiquitin-specific protease (synUSP, GenBankTM Accession no. AB073880). The homologous human gene was mapped to a locus on chromosome 1p36.12. The deduced synUSP protein consisted of 1036 amino acids, and possessed an ubiquitin-like domain at the C-terminus, Cys- and His-boxes, leucine zipper motifs, and six amino acid-repeats of L/ILCPHG. The protein possessed de-ubiquitinating activity toward a model substrate, as expected from its sequence. The protein of 125 kDa was present in the rat brain; in particular, it was enriched in the post-synaptic density and the dendritic lipid raft fractions. The immunostaining of cortical neurons confirmed the post-synaptic localization. The mRNA for synUSP was localized to dendrites, as well as somas, of neuronal cells. Thus, both the mRNA and the protein were localized in the post-synaptic compartments. These results suggest a regulatory mechanism for the ubiquitin-related system at the post-synaptic sites.
Collapse
Affiliation(s)
- Qing Bao Tian
- Department of Neuroplasty, Research Institute on Aging and Adaptation, Shinshu University Graduate School of Medicine, Matsumoto, Japan
| | | | | | | | | | | |
Collapse
|
38
|
Asaki C, Usuda N, Nakazawa A, Kametani K, Suzuki T. Localization of translational components at the ultramicroscopic level at postsynaptic sites of the rat brain. Brain Res 2003; 972:168-76. [PMID: 12711090 DOI: 10.1016/s0006-8993(03)02523-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We investigated the localization of components of translational machinery and their regulators in the postsynaptic region. We examined several components, especially those involved in translational regulation: components of (1) MAPK-Mnk-eIF4E, (2) PI3-kinase-PDK-Akt/PKB-FRAP/mTOR-PHAS/4EBP, (3) p70S6K-S6 ribosomal protein and (4) eEF2 kinase/CaMKIII-eEF2 pathways. Western blotting detected all the components examined in the synaptic fractions, and their differential localization to the synaptic subcompartments: initiation or elongation factors, except for eIF5, were detected predominantly in the dendritic lipid raft fraction, which contained ER marker proteins. In contrast, most of their regulatory kinases were distributed to both the postsynaptic density (PSD) and the dendritic lipid raft fractions, or enriched in the former fraction. Localization of eIF4E at synaptic sites was further examined immunohistochemically at the electron microscopic level. The eIF-4E-immunoreactivity was localized to the postsynaptic sites, especially to the microvesicle-like structures underneath the postsynaptic membrane in the spine, some of which were localized in close proximity to PSD. These results suggest that the postsynaptic local translational system, in at least four major regulatory pathways, is similar to those in the perinuclear one, and that it takes place, at least partly, immediately beneath the postsynaptic membrane. The results also suggest the presence of ER-associated type of translational machinery at the postsynaptic sites.
Collapse
Affiliation(s)
- Chie Asaki
- Department of Neuroplasticity, Research Center on Aging and Adaptation, Shinshu University, 3-1-1 Asahi, Matsumoto 390-8621, Japan
| | | | | | | | | |
Collapse
|
39
|
Zhang SSM, Wei JY, Li C, Barnstable CJ, Fu XY. Expression and activation of STAT proteins during mouse retina development. Exp Eye Res 2003; 76:421-31. [PMID: 12634107 DOI: 10.1016/s0014-4835(03)00002-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cytokines and growth factors play important roles in mammalian ocular development and maintenance. Recent studies have indicated that some of these ligands can activate signal transducer and activator of transcription factors (STATs) and modulate gene transcription. The purpose of this study was to investigate the expression and activation of STAT proteins in the developing mouse retina. Anti-STAT and anti-phosphorylated STAT antibodies were used to detect the expression and activation of STATs in embryonic and postnatal neuronal retina, ciliary margin, and retinal pigment epithelium (RPE). In situ hybridization and Western blot were also employed. In embryonic stages, all STAT proteins were expressed in the neuronal retina in distinct cell populations at different embryonic stages. For example, Stat3 expression and activation gradually increased in the inner neuroblast layer and ciliary margin during development. In adult retina, Stat3 was detected in the inner nuclear layer and ganglion cells layers. Stat1 was strongly expressed in both outer and inner plexiform layers. Stat5a was clearly expressed in the outer/inner nuclear layer, the ganglion cell layer, and the inner plexiform layer. Strong expression of Stat3, Stat5a, and Stat6 was observed in the RPE. Activated Stat3 and Stat5a were found in the neural retina and the RPE. Distinct STAT proteins were present in different cell populations in neuronal retina and RPE suggesting multiple functions of STATs in mammalian eye development. Studies of STAT signal pathways in the eye may contribute to the understanding of molecular mechanisms in control of ocular development and pathogenesis.
Collapse
Affiliation(s)
- Samuel Shao-Min Zhang
- Department of Pathology, Yale University School of Medicine, 310 Cedar Street, BML 117, New Haven, CT 06520-8023, USA.
| | | | | | | | | |
Collapse
|
40
|
Okano A, Usuda N, Furihata K, Nakayama K, Bao Tian Q, Okamoto T, Suzuki T. Huntingtin-interacting protein-1-related protein of rat (rHIP1R) is localized in the postsynaptic regions. Brain Res 2003; 967:210-25. [PMID: 12650982 DOI: 10.1016/s0006-8993(03)02236-4] [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: 11/16/2022]
Abstract
We cloned a rHIP1R (GenBank Accession No., AB005052) encoding a Sla2/huntingtin-interacting protein (HIP1) family protein from a rat brain cDNA library. Localization of rHIP1R was investigated in the rat brain using an antibody specific to the HIP1R antibody. The rHIP1R protein was enriched in the synaptic plasma membrane fraction along with huntingtin, a synaptic protein and a causal protein for Huntington's disease. The electron microscopic examination revealed that HIP1R was localized at postsynaptic spines. Localization of HIP1R in the small vesicular structures in the spine, possible sites of vesicular transport of synaptic proteins, together with the structure-based analysis, suggested a role of HIP1R for vesicle trafficking through interaction with F-actin and working together with huntingtin and HIP1 at the synaptic sites.
Collapse
Affiliation(s)
- Akira Okano
- Department of Neuroplasticity, Research Center on Aging and Adaptation, University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan
| | | | | | | | | | | | | |
Collapse
|
41
|
Erythropoietin is a paracrine mediator of ischemic tolerance in the brain: evidence from an in vitro model. J Neurosci 2002. [PMID: 12451129 DOI: 10.1523/jneurosci.22-23-10291.2002] [Citation(s) in RCA: 367] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In an in vitro model of cerebral ischemia (oxygen glucose deprivation, OGD) we investigated whether erythropoietin (EPO) plays a critical role in ischemic preconditioning. We found that EPO time and dose-dependently induced protection against OGD in rat primary cortical neurons. Protection was significant at 5 min and reached a maximum at 48 hr after EPO application. Protection was blocked by the coapplication of a soluble Epo receptor (sEpoR) or an antibody against EpoR (anti-EpoR). Medium transfer from OGD-treated astrocytes to untreated neurons induced protection against OGD in neurons, which was attenuated strongly by the application of sEpoR and anti-EpoR. In contrast, medium transfer from OGD-treated neurons to untreated neurons induced protection against OGD that did not involve EPO. In astrocytes the OGD enhanced the nuclear translocation of hypoxia-inducible factor 1 (HIF-1), the major transcription factor regulating EPO expression. Consequently, transcription of EPO-mRNA was increased in astrocytes after OGD. Cultured neurons express EpoR, and the Janus kinase-2 (JAK-2) inhibitor AG490 abolished EPO-induced tolerance against OGD. Furthermore, EPO-induced neuroprotection as well as phosphorylation of the proapoptotic Bcl family member Bad was reduced by the phosphoinositide-3 kinase (PI3K) inhibitor LY294002. The results suggest that astrocytes challenged with OGD provide paracrine protective signals to neurons. We provide evidence for the following signaling cascade: HIF-1 is activated rapidly by hypoxia in astrocytes. After HIF-1 activation the astrocytes express and release EPO. EPO activates the neuronal EPO receptor and, subsequently, JAK-2 and thereby PI3K. PI3K deactivates BAD via Akt-mediated phosphorylation and thus may inhibit hypoxia-induced apoptosis in neurons. Our results establish EPO as an important paracrine neuroprotective mediator of ischemic preconditioning.
Collapse
|
42
|
Abstract
Accumulating evidence suggests that special lipid microdomains in the lipid membrane play various roles in cellular functions. Neurons also have such microdomains, non-caveolar lipid rafts. However, the rafts at the synaptic sites had not been reported until 2001, when a raft-like fraction was purified from synaptic plasma membrane of the rat forebrain (Mol. Brain Res. 89 (2001) 20). This article reviews recent findings on lipid rafts, especially those in the brain, and discusses the possible interaction between the postsynaptic raft and the postsynaptic density, both of which are essential for the structure and function of the postsynaptic side of the synapse.
Collapse
Affiliation(s)
- Tatsuo Suzuki
- Department of Neuroplasticity, Research Center on Aging and Adaptation, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
| |
Collapse
|
43
|
Wen TC, Peng H, Hata R, Desaki J, Sakanaka M. Induction of phosphorylated-Stat3 following focal cerebral ischemia in mice. Neurosci Lett 2001; 303:153-6. [PMID: 11323108 DOI: 10.1016/s0304-3940(01)01711-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
It has been shown that Stat3 is induced following transient cerebral ischemia in rat. However there is no evidence that cerebral ischemia stimulates the expression of phosphorylated-Stat3 (p-Stat3), which can activate cytokine-mediated signal transduction from the membrane to the nucleus. In the present study, we investigated the changes in p-Stat3 expression following middle cerebral artery occlusion in mice. Western blot analysis revealed a significant increase in the p-Stat3 protein in the peripheral part of the ischemic area, starting from 6 h after ischemia. p-Stat3 immunoreactivity was detected only in neurons, but not in astrocytes or microglia, and p-Stat3-positive neurons were increased in number in the peripheral part of the ischemic area at 24 h after ischemia. Double staining with aTdT-mediated biotinylated UTP nick end labeling (TUNEL) kit and the p-Stat3 antibody indicated that p-Stat3-positive neurons were also TUNEL-positive. Subsequent immuno-electron microscopic observations showed that p-Stat3-positive neurons were at different stages of degeneration. The present findings suggest that the increased expression of p-Stat3 after cerebral ischemia could play a crucial role in ischemia-induced neuron death.
Collapse
Affiliation(s)
- T C Wen
- Department of Anatomy, Ehime University School of Medicine, Shigenobu, 791-0295, Ehime, Japan
| | | | | | | | | |
Collapse
|
44
|
Abstract
Heat shock proteins (HSPs) are induced not only by heat shock but also by various other environmental stresses. HSPs such as Hsp90, Hsp70, Hsp60, Hsp40 and Hsp28 are also expressed constitutively at normal growth temperatures and have basic and indispensable functions in the life cycle of proteins as molecular chaperones, as well as playing a role in protecting cells from deleterious stresses. Recently, Hsc70 and Hsp40 were found to be localized to the synapse in the mammalian central nervous system, indicating a synaptic role for these HSPs. Molecular chaperones are able to inhibit the aggregation of partially denatured proteins and refold them. In addition, molecular chaperones, especially Hsp70, protect the brain and heart from severe ischemia. In these respects, there are expectations for the use of molecular chaperones for protection against and therapeutic treatment of inherited diseases caused by protein misfolding. In this study, we review Hsp70 and Hsp40, and refer to the roles of these molecules in the synapse and cytoprotective functions of HSPs in stress tolerance and neurodegenerative diseases.
Collapse
Affiliation(s)
- K Ohtsuka
- Cell Stress Biology Research Group, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya, Japan
| | | |
Collapse
|