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Illes S. More than a drainage fluid: the role of CSF in signaling in the brain and other effects on brain tissue. HANDBOOK OF CLINICAL NEUROLOGY 2018; 146:33-46. [PMID: 29110778 DOI: 10.1016/b978-0-12-804279-3.00003-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Current progress in neuroscience demonstrates that the brain is not an isolated organ and is influenced by the systemic environment and extracerebral processes within the body. In view of this new concept, blood and cerebrospinal fluid (CSF) are important body fluids linking extracerebral and intracerebral processes. For decades, substantial evidence has been accumulated indicating that CSF modulates brain states and influences behavior as well as cognition. This chapter provides an overview of how CSF directly modulates the function of different types of brain cells, such as neurons, neural stem cells, and CSF-contacting cells. Alterations in CSF content occur in most pathologic central nervous system (CNS) conditions. In a classic view, the function of CSF is to drain waste products and detrimental factors derived from diseased brain parenchyma. This chapter presents examples for how intra- and extracerebral pathologic processes lead to alterations in the CSF content. Current knowledge about how pathologically altered CSF influences the functionality of brain cells will be presented. Thereby, it becomes evident that CSF has more than a drainage function and has a causal role for the etiology and pathogenesis of different CNS diseases.
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Affiliation(s)
- Sebastian Illes
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
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2
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Ewanchuk BW, Allan ERO, Warren AL, Ramachandran R, Yates RM. The cooling compound icilin attenuates autoimmune neuroinflammation through modulation of the T-cell response. FASEB J 2017; 32:1236-1249. [PMID: 29114087 DOI: 10.1096/fj.201700552r] [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] [Indexed: 11/11/2022]
Abstract
The synthetic supercooling drug, icilin, and its primary receptor target, the cation channel transient receptor potential (TRP) melastatin-8 (TRPM8), have been described as potent negative regulators of inflammation in the colon. The aim of this study was to determine whether the anti-inflammatory action of icilin could potentially be used to treat autoimmune neuroinflammatory disorders, such as multiple sclerosis (MS). During experimental autoimmune encephalomyelitis (EAE)-a CD4+ T cell-driven murine model of MS-we found that both wild-type (WT) and TRPM8-deficient EAE mice were protected from disease progression during icilin treatment, as evidenced by delays in clinical onset and reductions in neuroinflammation. In vitro, icilin potently inhibited the proliferation of murine and human CD4+ T cells, with the peripheral expansion of autoantigen-restricted T cells similarly diminished by the administration of icilin in mice. Attenuation of both TRPM8-/- and TRP ankyrin-1-/- T-cell proliferation by icilin was consistent with the WT phenotype, which suggests a mechanism that is independent of these channels. In addition, icilin treatment altered the expressional profile of activated CD4+ T cells to one that was indicative of restricted effector function and limited neuroinflammatory potential. These findings identify a potent anti-inflammatory role for icilin in lymphocyte-mediated neuroinflammation and highlight clear pleiotropic effects of the compound beyond classic TRP channel activation.-Ewanchuk, B. W., Allan, E. R. O., Warren, A. L., Ramachandran, R., Yates, R. M. The cooling compound icilin attenuates autoimmune neuroinflammation through modulation of the T-cell response.
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Affiliation(s)
- Benjamin W Ewanchuk
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Euan R O Allan
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Amy L Warren
- Department of Veterinary Clinical and Diagnostic Sciences, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Rithwik Ramachandran
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Robin M Yates
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
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Changes in GABAergic markers accompany degradation of neuronal function in the primary visual cortex of senescent rats. Sci Rep 2017; 7:14897. [PMID: 29097694 PMCID: PMC5668371 DOI: 10.1038/s41598-017-15006-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/19/2017] [Indexed: 11/14/2022] Open
Abstract
Numerous studies have reported age-dependent degradation of neuronal function in the visual cortex and have attributed this functional decline to weakened intracortical inhibition, especially GABAergic inhibition. However, whether this type of functional decline is linked to compromised GABAergic inhibition has not been fully confirmed. Here, we compared the neuronal response properties and markers of GABAergic inhibition in the primary visual cortex (V1) of young adult and senescent rats. Compared with those of young adult rats, old rats’ V1 neurons exhibited significantly increased visually evoked responses and spontaneous activity, a decreased signal-to-noise ratio and reduced response selectivity for the stimulus orientation and motion direction. Additionally, the ratio of GABA-positive neurons to total cortical neurons in old rats was significantly decreased compared with that in young rats. Expression of the key GABA-synthesizing enzyme GAD67 was significantly lower in old rats than in young rats, although GAD65 expression showed a marginal difference between the two age groups. Further, expression of an important GABAA receptor subunit, GABAAR α1, was significantly attenuated in old rats relative to young ones. These results demonstrate that ageing may result in decreased GABAergic inhibition in the visual cortex and that this decrease in GABAergic inhibition accompanies neuronal function degradation.
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Djenoune L, Wyart C. Light on a sensory interface linking the cerebrospinal fluid to motor circuits in vertebrates. J Neurogenet 2017; 31:113-127. [PMID: 28789587 DOI: 10.1080/01677063.2017.1359833] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The cerebrospinal fluid (CSF) is circulating around the entire central nervous system (CNS). The main function of the CSF has been thought to insure the global homeostasis of the CNS. Recent evidence indicates that the CSF also dynamically conveys signals modulating the development and the activity of the nervous system. The later observation implies that cues from the CSF could act on neurons in the brain and the spinal cord via bordering receptor cells. Candidate neurons to enable such modulation are the cerebrospinal fluid-contacting neurons (CSF-cNs) that are located precisely at the interface between the CSF and neuronal circuits. The atypical apical extension of CSF-cNs bears a cluster of microvilli bathing in the CSF indicating putative sensory or secretory roles in relation with the CSF. In the brainstem and spinal cord, CSF-cNs have been described in over two hundred species by Kolmer and Agduhr, suggesting an important function within the spinal cord. However, the lack of specific markers and the difficulty to access CSF-cNs hampered their physiological investigation. The transient receptor potential channel PKD2L1 is a specific marker of spinal CSF-cNs in vertebrate species. The transparency of zebrafish at early stages eases the functional characterization of pkd2l1+ CSF-cNs. Recent studies demonstrate that spinal CSF-cNs detect spinal curvature via the channel PKD2L1 and modulate locomotion and posture by projecting onto spinal interneurons and motor neurons in vivo. In vitro recordings demonstrated that spinal CSF-cNs are sensing pH variations mainly through ASIC channels, in combination with PKD2L1. Altogether, neurons contacting the CSF appear as a novel sensory modality enabling the detection of mechanical and chemical stimuli from the CSF and modulating the excitability of spinal circuits underlying locomotion and posture.
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Affiliation(s)
- Lydia Djenoune
- a Institut du Cerveau et de la Moelle épinière (ICM) , Paris , France
| | - Claire Wyart
- a Institut du Cerveau et de la Moelle épinière (ICM) , Paris , France
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Zhang C, Li Y, Wang X, Fei Y, Zhang L. Involvement of neurokinin 1 receptor within the cerebrospinal fluid‑contacting nucleus in visceral pain. Mol Med Rep 2017; 15:4300-4304. [PMID: 28440440 DOI: 10.3892/mmr.2017.6499] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 02/13/2017] [Indexed: 11/06/2022] Open
Abstract
Studies have shown that the cerebrospinal fluid‑contacting nucleus (CSF‑CN) may be associated with the transduction and regulation of pain signals. However, the role of the CSF‑CN remains to be elucidated. Emerging evidence has suggested that neurokinin 1 receptor (NK1R) is important in the development of visceral pain and hyperalgesia, however, whether NK1R exists in the CSF‑CN and its exact role in visceral pain remain to be fully elucidated. In the present study, double‑labeled immunofluorescence staining and western blot analysis were performed to investigate this. It was revealed that NK1R was distributed in the CSF‑CN. Following the induction of visceral pain by formalin instillation, NK1R in the CSF‑CN was upregulated. In addition, by observing the behaviors of rats subjected to visceral pain, it was found that visceral pain was relieved by lateral intracerbroventricular injection of the NK1R antagonist, RP67580. These data provided a broader understanding of the role of NK1R in the CSF‑CN and demonstrated that the CSF‑CN was involved in acute visceral pain via the regulation of NK1R.
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Affiliation(s)
- Chao Zhang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Ying Li
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Xin Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Yan Fei
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Licai Zhang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
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Role of the RVM in Descending Pain Regulation Originating from the Cerebrospinal Fluid-Contacting Nucleus. Neurochem Res 2016; 41:1651-61. [DOI: 10.1007/s11064-016-1880-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 02/25/2016] [Accepted: 02/29/2016] [Indexed: 01/09/2023]
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Role of cerebrospinal fluid-contacting nucleus in sodium sensing and sodium appetite. Physiol Behav 2015; 147:291-9. [DOI: 10.1016/j.physbeh.2015.04.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 11/23/2022]
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8
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Zhang E, Liao P. Brain transient receptor potential channels and stroke. J Neurosci Res 2014; 93:1165-83. [PMID: 25502473 DOI: 10.1002/jnr.23529] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/10/2014] [Accepted: 11/04/2014] [Indexed: 02/06/2023]
Abstract
Transient receptor potential (TRP) channels have been increasingly implicated in the pathological mechanisms of CNS disorders. TRP expression has been detected in neurons, astrocytes, oligodendrocytes, microglia, and ependymal cells as well as in the cerebral vascular endothelium and smooth muscle. In stroke, TRPC3/4/6, TRPM2/4/7, and TRPV1/3/4 channels have been found to participate in ischemia-induced cell death, whereas other TRP channels, in particular those expressed in nonneuronal cells, have been less well studied. This review summarizes the current knowledge on the expression and functions of the TRP channels in various cell types in the brain and our current understanding of TRP channels in stroke pathophysiology. In an aging society, the occurrence of stroke is expected to increase steadily, and there is an urgent requirement to improve the current stroke management strategy. Therefore, elucidating the roles of TRP channels in stroke could shed light on the development of novel therapeutic strategies and ultimately improve stroke outcome.
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Affiliation(s)
- Eric Zhang
- Calcium Signalling Laboratory, National Neuroscience Institute, Singapore
| | - Ping Liao
- Calcium Signalling Laboratory, National Neuroscience Institute, Singapore.,Duke-NUS Graduate Medical School Singapore, Singapore
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Liu H, Yan WW, Lu XX, Zhang XL, Wei JQ, Wang XY, Wang T, Wu T, Cao J, Shao CJ, Zhou F, Zhang HX, Zhang P, Zang T, Lu XF, Cao JL, Ding HL, Zhang LC. Role of the cerebrospinal fluid-contacting nucleus in the descending inhibition of spinal pain transmission. Exp Neurol 2014; 261:475-85. [DOI: 10.1016/j.expneurol.2014.07.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 07/19/2014] [Accepted: 07/29/2014] [Indexed: 01/07/2023]
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Wang J, Zhang S, Li L, Zhang L. Involvement of Wnt5a within the cerebrospinal fluid-contacting nucleus in nerve injury-induced neuropathic pain. Int J Neurosci 2014; 125:147-53. [PMID: 24738716 DOI: 10.3109/00207454.2014.915399] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Studies have demonstrated that the cerebrospinal fluid-contacting nucleus (CSF-CN) is involved in neuropathic pain, but the underlying molecular mechanisms still largely remain obscure. Emerging evidence suggests that spinal Wnt5a plays a crucial role in regulation of chronic pain. However, little is known about the potential role of the supraspinal Wnt5a in the development of chronic pain. To investigate whether Wnt5a exists in the CSF-CN and its role in neuropathic pain, double-labeled immunofluorescence staining was used to identify the expression of Wnt5a in the CSF-CN and western blot analysis of the CSF-CN was employed to verify the alteration of Wnt5a protein in the process of neuropathic pain. In the present study, we demonstrated that Wnt5a is distributed in the CSF-CN and the Wnt5a protein was up-regulated by nerve injury-induced nociceptive stimuli. Furthermore, lateral intracerebroventricular injection of Wnt5a antagonist Box5 attenuated the chronic constriction injury (CCI)-induced neuropathic pain and down-regulated the expression of Wnt5a in the CSF-CN. These data extend our understanding of the role of Wnt5a in supraspinal site and demonstrate that the CSF-CN participates in nerve injury-induced neuropathic pain via the regulation of Wnt5a.
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Affiliation(s)
- Jinfeng Wang
- Jiangsu Key Laboratory of Anesthesiology & Jiangsu Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical College , Xuzhou, Jiangsu , China
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Mao SS, Hua R, Zhao XP, Qin X, Sun ZQ, Zhang Y, Wu YQ, Jia MX, Cao JL, Zhang YM. Exogenous administration of PACAP alleviates traumatic brain injury in rats through a mechanism involving the TLR4/MyD88/NF-κB pathway. J Neurotrauma 2013; 29:1941-59. [PMID: 22583372 DOI: 10.1089/neu.2011.2244] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) is effective in reducing axonal damage associated with traumatic brain injury (TBI), and has immunomodulatory properties. Toll-like receptor 4 (TLR4) is an important mediator of the innate immune response. It significantly contributes to neuroinflammation induced by brain injury. However, it remains unknown whether exogenous PACAP can modulate TBI through the TLR4/adapter protein myeloid differentiation factor 88 (MyD88)/nuclear factor-κB (NF-κB) signaling pathway. In this study, we investigated the potential neuroprotective mechanisms of PACAP pretreatment in a weight-drop model of TBI. PACAP38 was microinjected intracerebroventricularly before TBI. Brain samples were extracted from the pericontusional area in the cortex and hippocampus. We found that TBI induced significant upregulation of TLR4, with peak expression occurring 24 h post-trauma, and that pretreatment with PACAP significantly improved motor and cognitive dysfunction, attenuated neuronal apoptosis, and decreased brain edema. Pretreatment with PACAP inhibited upregulation of TLR4 and its downstream signaling molecules MyD88, p-IκB, and NF-κB, and suppressed increases in the levels of the downstream inflammatory agents interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), in the brain tissue around the injured cortex and in the hippocampus. Administration of PACAP both in vitro and in vivo attenuated the ability of the TLR4 agonist lipopolysaccharide (LPS) to increase TLR4 protein levels. Therefore, PACAP exerts a neuroprotective effect in this rat model of TBI, by inhibiting a secondary inflammatory response mediated by the TLR4/MyD88/NF-κB signaling pathway in microglia and neurons, thereby reducing neuronal death and improving the outcome following TBI.
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Affiliation(s)
- Shan-Shan Mao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, Jiangsu, China
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Evaluation of three tracers for labeling distal cerebrospinal fluid-contacting neurons. Neurosci Bull 2013; 29:576-80. [PMID: 23585297 DOI: 10.1007/s12264-013-1332-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 12/17/2012] [Indexed: 01/26/2023] Open
Abstract
It has been reported that distal cerebrospinal fluid-contacting neurons (dCSF-CNs) can be detected by immunohistochemical assay using cholera toxin subunit B-conjugated horseradish peroxidase (CB-HRP). In the present study, another two methods with CB alone or CB-conjugated FITC (CB-FITC) were used, and the results from the three methods were compared. Adult Sprague-Dawley rats were randomly divided into three groups with CB-HRP, CB or CB-FITC. Tracers were diluted to 30% in artificial cerebrospinal fluid and injected separately (in a volume of 3 μL) into the lateral ventricle. Animals from the CB-HRP and CB groups were perfused 48 h after surgery while animals from the CB-FITC group were perfused 1, 3, 6, 12, 24 or 48 h after surgery. The brain was sectioned (40 μm) for immunofluorescence and five sections with positive neurons were selected from each rat for neuron counting. Three clusters of positive neurons in a 'Y-like' distribution were detected ventral to the cerebral aqueduct of rats from the three groups. No significant difference was observed among the quantitative data. In the CB-FITC group, stable staining was detected even at 6 h after injection. Taken together, lateral ventricle injection of CB/CB-FITC is a useful method for labeling dCSF-CNs in rats. The CB-FITC method makes dCSF-CNs labeling much simpler and more convenient.
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Abstract
The Transient receptor potential (TRP) family of cation channels is a large protein family, which is mainly structurally uniform. Proteins consist typically of six transmembrane domains and mostly four subunits are necessary to form a functional channel. Apart from this, TRP channels display a wide variety of activation mechanisms (ligand binding, G-protein coupled receptor dependent, physical stimuli such as temperature, pressure, etc.) and ion selectivity profiles (from highly Ca(2+) selective to non-selective for cations). They have been described now in almost every tissue of the body, including peripheral and central neurons. Especially in the sensory nervous system the role of several TRP channels is already described on a detailed level. This review summarizes data that is currently available on their role in the central nervous system. TRP channels are involved in neurogenesis and brain development, synaptic transmission and they play a key role in the development of several neurological diseases.
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Liu Y, Qin N. TRPM8 in health and disease: cold sensing and beyond. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 704:185-208. [PMID: 21290296 DOI: 10.1007/978-94-007-0265-3_10] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review focuses on TRPM8, one of the approximately 30 members of the diverse family of transient receptor potential (TRP) ion channels. Initially identified from the prostate, TRPM8 has been studied more extensively in the sensory system and is best established as a major transducer of environmental cold temperatures. An increasing body of evidence suggests that it may also be an important player in various chronic conditions, such as inflammatory/neuropathic pain and prostate cancer. Small molecule compounds that selectively modulate TRPM8 are beginning to emerge and will be critically valuable for better understanding the role of this channel in both physiological and pathological states, on which the prospects of TRPM8 as a viable therapeutic target rest.
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Affiliation(s)
- Yi Liu
- Johnson & Johnson Pharmaceutical Research and Development, LLC, San Diego, CA 92121, USA.
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Lu XF, Li YY, Wang CG, Wei JQ, Ye Y, Zhang LC, Cao JL. Substance P in the cerebrospinal fluid-contacting nucleus contributes to morphine physical dependence in rats. Neurosci Lett 2011; 488:188-92. [DOI: 10.1016/j.neulet.2010.11.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2010] [Revised: 11/08/2010] [Accepted: 11/09/2010] [Indexed: 10/18/2022]
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Du J, Sun B, Chen K, Zhang L, Liu S, Gu Q, Fan L, Zhao N, Wang Z. Metabolites of cerebellar neurons and hippocampal neurons play opposite roles in pathogenesis of Alzheimer's disease. PLoS One 2009; 4:e5530. [PMID: 19436731 PMCID: PMC2677455 DOI: 10.1371/journal.pone.0005530] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Accepted: 04/01/2009] [Indexed: 12/31/2022] Open
Abstract
Metabolites of neural cells, is known to have a significant effect on the normal physiology and function of neurons in brain. However, whether they play a role in pathogenesis of neurodegenerative diseases is unknown. Here, we show that metabolites of neurons play essential role in the pathogenesis of Alzheimer's disease (AD). Firstly, in vivo and in vitro metabolites of cerebellar neurons both significantly induced the expression of Aβ-degrading enzymes in the hippocampus and cerebral cortex and promoted Aβ clearance. Moreover, metabolites of cerebellar neurons significantly reduced brain Aβ levels and reversed cognitive impairments and other AD-like phenotypes of APP/PS1 transgenic mice, in both early and late stages of AD pathology. On the other hand, metabolites of hippocampal neurons reduced the expression of Aβ-degrading enzymes in the cerebellum and caused cerebellar neurodegeneration in APP/PS1 transgenic mice. Thus, we report, for the first time, that metabolites of neurons not only are required for maintaining the normal physiology of neurons but also play essential role in the pathogenesis of AD and may be responsible for the regional-specificity of Aβ deposition and AD pathology.
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Affiliation(s)
- Jing Du
- Protein Science Key Laboratory of the Ministry of Education, Department of Biological Sciences and Biotechnology, School of Medicine, Tsinghua University, Beijing, People's Republic of China
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Du J, Sun B, Chen K, Fan L, Wang Z. Antagonist of peroxisome proliferator-activated receptor gamma induces cerebellar amyloid-beta levels and motor dysfunction in APP/PS1 transgenic mice. Biochem Biophys Res Commun 2009; 384:357-61. [PMID: 19422805 DOI: 10.1016/j.bbrc.2009.04.148] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Accepted: 04/29/2009] [Indexed: 12/23/2022]
Abstract
Recent evidences show that peroxisome proliferator-activated receptor gamma (PPARgamma) is involved in the modulation of the amyloid-beta (Abeta) cascade causing Alzheimer's disease (AD) and treatment with PPARgamma agonists protects against AD pathology. However, the function of PPARgamma steady-state activity in Abeta cascade and AD pathology remains unclear. In this study, an antagonist of PPARgamma, GW9662, was injected into the fourth ventricle of APP/PS1 transgenic mice to inhibit PPARgamma activity in cerebellum. The results show that inhibition of PPARgamma significantly induced Abeta levels in cerebellum and caused cerebellar motor dysfunction in APP/PS1 transgenic mice. Moreover, GW9662 treatment markedly decreased the cerebellar levels of insulin-degrading enzyme (IDE), which is responsible for the cellular degradation of Abeta. Since cerebellum is spared from significant Abeta accumulation and neurotoxicity in AD patients and animal models, these findings suggest a crucial role of PPARgamma steady-state activity in protection of cerebellum against AD pathology.
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Affiliation(s)
- Jing Du
- Protein Science Key Laboratory of the Ministry of Education, Department of Biological Sciences and Biotechnology, School of Medicine, Tsinghua University, Beijing 100084, PR China
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