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Annam J, Galfalvy HC, Keilp JG, Simpson N, Huang YY, Nandakumar R, Byrnes A, Nitahara K, Hall A, Stanley B, Mann JJ, Sublette ME. Plasma cytokine and growth factor response to acute psychosocial stress in major depressive disorder. J Psychiatr Res 2024; 169:224-230. [PMID: 38043258 DOI: 10.1016/j.jpsychires.2023.11.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 09/12/2023] [Accepted: 11/16/2023] [Indexed: 12/05/2023]
Abstract
BACKGROUND Pro-inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α are elevated in response to psychosocial stress; however, less is known about other inflammatory markers. METHODS We explored response to the Trier Social Stress Test (TSST) of 16 cytokines and growth factors in patients with major depressive disorder (MDD, n = 12) vs. healthy volunteers (HV, n = 16). Outcomes were baseline and post-stress levels estimated by area under the curve (AUCi) and peak change over 3 timepoints. We also explored correlations between biomarkers and clinical characteristics. RESULTS Baseline concentrations were higher in MDD for platelet-derived growth factor (PDGF)-AB/BB (p = 0.037, d = 0.70), granulocyte-macrophage colony-stimulating factor (GM-CSF, p = 0.033, d = 0.52), and IL-8 (p = 0.046, d = 0.74). After TSST, AUCi was higher in MDD for GM-CSF (p = 0.003, d = 1.21), IL-5 (p = 0.014, d = 1.62), and IL-27 (p = 0.041, d = 0.74). In MDD, depression severity correlated positively with soluble CD40L (sCD40L) for AUCi (Spearman's ρ = 0.76, p = 0.004) and with baseline vascular endothelial growth factor A (VEGFA, r = 0.85, p < 0.001), but negatively with baseline monokine induced by gamma interferon (MIG, aka CXCL9; r = -0.77, p = 0.003). CONCLUSIONS Effect sizes were robust in this exploratory study, although interpretation of the results must be cautious, given small sample size and multiple comparisons. Differential study of stress-induced biomarkers may have important ramifications for MDD treatment.
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Affiliation(s)
- Jayabhargav Annam
- Department of Psychiatry, Columbia University, New York, NY, USA; Albert Einstein College of Medicine, New York, NY, USA
| | - Hanga C Galfalvy
- Department of Psychiatry, Columbia University, New York, NY, USA; Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA; Department of Biostatistics, Mailman School of Public Health, New York, NY, USA
| | - John G Keilp
- Department of Psychiatry, Columbia University, New York, NY, USA; Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA
| | - Norman Simpson
- Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA
| | - Yung-Yu Huang
- Department of Psychiatry, Columbia University, New York, NY, USA; Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA
| | - Renu Nandakumar
- Biomarkers Core Laboratory, Columbia University, New York, NY, USA
| | - Abigail Byrnes
- Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA
| | - Kayla Nitahara
- Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA
| | - Aimee Hall
- Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA
| | - Barbara Stanley
- Department of Psychiatry, Columbia University, New York, NY, USA; Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA
| | - J John Mann
- Department of Psychiatry, Columbia University, New York, NY, USA; Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA; Department of Radiology, Columbia University, New York, NY, USA
| | - M Elizabeth Sublette
- Department of Psychiatry, Columbia University, New York, NY, USA; Molecular Imaging & Neuropathology Area, New York State Psychiatric Institute, New York, NY, USA.
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Platelet-derived growth factor BB: A potential diagnostic blood biomarker for differentiating bipolar disorder from major depressive disorder. J Psychiatr Res 2021; 134:48-56. [PMID: 33360224 DOI: 10.1016/j.jpsychires.2020.12.051] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 12/10/2020] [Accepted: 12/17/2020] [Indexed: 01/19/2023]
Abstract
Bipolar disorder (BD) is frequently misdiagnosed as major depressive disorder (MDD) due to overlapping depressive symptoms. This study investigated whether serum platelet-derived growth factor BB (PDGF-BB) is a differential diagnostic biomarker for BD and MDD. An initial SOMAscan proteomics assay of 1311 proteins in small samples from patients with BD and MDD and healthy controls (HCs) suggested that serum levels of PDGF-BB differed between BD and MDD. We then conducted a two-step, exploratory, cross-sectional, case-control study at our institute and five sites that included a total of 549 participants (157 with BD, 144 with MDD, and 248 HCs). Clinical symptoms were assessed using the Hamilton Depression Rating Scale and the Young Mania Rating Scale. In the initial analysis at our institute, serum PDGF-BB levels in the MDD group (n = 36) were significantly lower than those in the BD (n = 39) and HC groups (n = 36). In the multicenter study, serum PDGF-BB levels in the MDD group were again significantly lower than those in the BD and HC groups, with no significant difference between the BD and HC groups. Treatment with sodium valproate was associated with significantly lower serum PDGF-BB levels in patients with BD. After controlling for confounding factors (sex, age, body mass index, clinical severity, and valproate medication), serum PDGF-BB levels were lower in the MDD group than in the BD group regardless of mood state. Our findings suggest that serum PDGF-BB may be a potential biomarker to differentiate BD and MDD.
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Kittel-Schneider S, Hahn T, Haenisch F, McNeill R, Reif A, Bahn S. Proteomic Profiling as a Diagnostic Biomarker for Discriminating Between Bipolar and Unipolar Depression. Front Psychiatry 2020; 11:189. [PMID: 32372978 PMCID: PMC7184109 DOI: 10.3389/fpsyt.2020.00189] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 02/26/2020] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Affective disorders are a major global burden, with approximately 15% of people worldwide suffering from some form of affective disorder. In patients experiencing their first depressive episode, in most cases it cannot be distinguished whether this is due to bipolar disorder (BD) or major depressive disorder (MDD). Valid fluid biomarkers able to discriminate between the two disorders in a clinical setting are not yet available. MATERIAL AND METHODS Seventy depressed patients suffering from BD (bipolar I and II subtypes) and 42 patients with major MDD were recruited and blood samples were taken for proteomic analyses after 8 h fasting. Proteomic profiles were analyzed using the Multiplex Immunoassay platform from Myriad Rules Based Medicine (Myriad RBM; Austin, Texas, USA). Human DiscoveryMAPTM was used to measure the concentration of various proteins, peptides, and small molecules. A multivariate predictive model was consequently constructed to differentiate between BD and MDD. RESULTS Based on the various proteomic profiles, the algorithm could discriminate depressed BD patients from MDD patients with an accuracy of 67%. DISCUSSION The results of this preliminary study suggest that future discrimination between bipolar and unipolar depression in a single case could be possible, using predictive biomarker models based on blood proteomic profiling.
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Affiliation(s)
- Sarah Kittel-Schneider
- Department of Psychiatry, Psychotherapy and Psychosomatic Medicine, University Hospital, University of Würzburg, Würzburg, Germany.,Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital, Goethe-University of Frankfurt, Frankfurt, Germany
| | - Tim Hahn
- Department of Psychiatry, Psychotherapy and Psychosomatic Medicine, University Hospital, University of Münster, Münster, Germany
| | - Frieder Haenisch
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
| | - Rhiannon McNeill
- Department of Psychiatry, Psychotherapy and Psychosomatic Medicine, University Hospital, University of Würzburg, Würzburg, Germany
| | - Andreas Reif
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital, Goethe-University of Frankfurt, Frankfurt, Germany
| | - Sabine Bahn
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
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4
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Quatredeniers M, Nakhleh MK, Dumas SJ, Courboulin A, Vinhas MC, Antigny F, Phan C, Guignabert C, Bendifallah I, Vocelle M, Fadel E, Dorfmüller P, Humbert M, Cohen-Kaminsky S. Functional interaction between PDGFβ and GluN2B-containing NMDA receptors in smooth muscle cell proliferation and migration in pulmonary arterial hypertension. Am J Physiol Lung Cell Mol Physiol 2018; 316:L445-L455. [PMID: 30543306 DOI: 10.1152/ajplung.00537.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this study, we explored the complex interactions between platelet-derived growth factor (PDGF) and N-methyl-d-aspartate receptor (NMDAR) and their effect on the excessive proliferation and migration of smooth muscle cells leading to obstructed arteries in pulmonary arterial hypertension (PAH). We report lower expression of glutamate receptor NMDA-type subunit 2B (GluN2B), a subunit composing NMDARs expected to affect cell survival/proliferation of pulmonary artery smooth muscle cells (PASMCs), in PAH patient lungs. PASMC exposure to PDGF-BB stimulated immediate increased levels of phosphorylated Src family kinases (SFKs) together with increased phosphorylated GluN2B (its active form) and cell surface relocalization, suggesting a cross talk between PDGFR-recruited SFKs and NMDAR. Selective inhibition of PDGFR-β or SFKs with imatinib or A-419259, respectively, on one hand, or with specific small-interfering RNAs (siRNAs) on the other hand, aborted PDGF-induced phosphorylation of GluN2B, thus validating the pathway. Selective inhibition of GluN2B using Rö25-6981 and silencing with specific siRNA, in the presence of PDGF-BB, significantly increased both migration and proliferation of PASMCs, thus strengthening the functional importance of the pathway. Together, these results indicate that GluN2B-type NMDAR activation may confer to PASMCs antiproliferative and antimigratory properties. The decreased levels of GluN2B observed in PAH pulmonary arteries could mediate the excessive proliferation of PASMCs, thus contributing to medial hyperplasia and PAH development.
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Affiliation(s)
- Marceau Quatredeniers
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Morad K Nakhleh
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Sébastien J Dumas
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Audrey Courboulin
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Maria C Vinhas
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Fabrice Antigny
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Carole Phan
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Christophe Guignabert
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Imane Bendifallah
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Matthieu Vocelle
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Elie Fadel
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Peter Dorfmüller
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Marc Humbert
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France.,AP-HP Assistance Publique-Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire Sévère, DHU Thorax Innovation, Hôpital Bicêtre, Le Kremlin-Bicêtre, France
| | - Sylvia Cohen-Kaminsky
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.,Université Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
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Recent progress in understanding subtype specific regulation of NMDA receptors by G Protein Coupled Receptors (GPCRs). Int J Mol Sci 2014; 15:3003-24. [PMID: 24562329 PMCID: PMC3958896 DOI: 10.3390/ijms15023003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 12/30/2013] [Accepted: 02/12/2014] [Indexed: 12/24/2022] Open
Abstract
G Protein Coupled Receptors (GPCRs) are the largest family of receptors whose ligands constitute nearly a third of prescription drugs in the market. They are widely involved in diverse physiological functions including learning and memory. NMDA receptors (NMDARs), which belong to the ionotropic glutamate receptor family, are likewise ubiquitously expressed in the central nervous system (CNS) and play a pivotal role in learning and memory. Despite its critical contribution to physiological and pathophysiological processes, few pharmacological interventions aimed directly at regulating NMDAR function have been developed to date. However, it is well established that NMDAR function is precisely regulated by cellular signalling cascades recruited downstream of G protein coupled receptor (GPCR) stimulation. Accordingly, the downstream regulation of NMDARs likely represents an important determinant of outcome following treatment with neuropsychiatric agents that target selected GPCRs. Importantly, the functional consequence of such regulation on NMDAR function varies, based not only on the identity of the GPCR, but also on the cell type in which relevant receptors are expressed. Indeed, the mechanisms responsible for regulating NMDARs by GPCRs involve numerous intracellular signalling molecules and regulatory proteins that vary from one cell type to another. In the present article, we highlight recent findings from studies that have uncovered novel mechanisms by which selected GPCRs regulate NMDAR function and consequently NMDAR-dependent plasticity.
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Sasaki-Hamada S, Tamaki K, Otsuka H, Ueno T, Sacai H, Niu Y, Matsumoto K, Oka J. Chotosan, a Kampo Formula, Ameliorates Hippocampal LTD and Cognitive Deficits in Juvenile-Onset Diabetes Rats. J Pharmacol Sci 2014; 124:192-200. [DOI: 10.1254/jphs.13179fp] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Matsumoto K, Zhao Q, Niu Y, Fujiwara H, Tanaka K, Sasaki-Hamada S, Oka JI. Kampo formulations, chotosan, and yokukansan, for dementia therapy: existing clinical and preclinical evidence. J Pharmacol Sci 2013; 122:257-69. [PMID: 23883485 DOI: 10.1254/jphs.13r03cr] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Cognitive deficits and behavioral and psychological symptoms of dementia (BPSD) are typical features of patients with dementia such as Alzheimer's disease (AD), vascular dementia (VD), and other forms of senile dementia. Clinical evidence has demonstrated the potential usefulness of chotosan (CTS) and yokukansan (YKS), traditional herbal formulations called Kampo medicines, in the treatment of cognitive disturbance and BPSD in dementia patients, although the indications targeted by CTS and YKS in Kampo medicine differ. The availability of CTS and YKS for treating dementia patients is supported by preclinical studies using animal models of dementia that include cognitive/emotional deficits caused by aging and diabetes, dementia risk factors. These studies have led not only to the concept of a neuronal basis for the CTS- and YKS-induced amelioration of cognitive function and emotional/psychiatric symptom-related behavior in animal models, but also to a proposal that ingredient(s) of Uncariae Uncis cum Ramulus, a medicinal herb included in CTS and YKS, may play an important role in the actions of these formulae in dementia patients. Further studies are needed to clarify the active ingredients of these formulae and their target endogenous molecules implicated in the anti-dementia drug-like actions.
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Affiliation(s)
- Kinzo Matsumoto
- Division of Medicinal Pharmacology, Institute of Natural Medicine, University of Toyama, Japan.
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Funa K, Sasahara M. The roles of PDGF in development and during neurogenesis in the normal and diseased nervous system. J Neuroimmune Pharmacol 2013; 9:168-81. [PMID: 23771592 PMCID: PMC3955130 DOI: 10.1007/s11481-013-9479-z] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 05/23/2013] [Indexed: 12/13/2022]
Abstract
The four platelet-derived growth factor (PDGF) ligands and PDGF receptors (PDGFRs), α and β (PDGFRA, PDGFRB), are essential proteins that are expressed during embryonic and mature nervous systems, i.e., in neural progenitors, neurons, astrocytes, oligodendrocytes, and vascular cells. PDGF exerts essential roles from the gastrulation period to adult neuronal maintenance by contributing to the regulation of development of preplacodal progenitors, placodal ectoderm, and neural crest cells to adult neural progenitors, in coordinating with other factors. In adulthood, PDGF plays critical roles for maintenance of many specific cell types in the nervous system together with vascular cells through controlling the blood brain barrier homeostasis. At injury or various stresses, PDGF modulates neuronal excitability through adjusting various ion channels, and affecting synaptic plasticity and function. Furthermore, PDGF stimulates survival signals, majorly PI3-K/Akt pathway but also other ways, rescuing cells from apoptosis. Studies imply an involvement of PDGF in dendrite spine morphology, being critical for memory in the developing brain. Recent studies suggest association of PDGF genes with neuropsychiatric disorders. In this review, we will describe the roles of PDGF in the nervous system, from the discovery to recent findings, in order to understand the broad spectrum of PDGF in the nervous system. Recent development of pharmacological and replacement therapies targeting the PDGF system is discussed.
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Affiliation(s)
- Keiko Funa
- Sahlgrenska Cancer Center, University of Gothenburg, Box 425, SE 405 30, Gothenburg, Sweden,
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de Bartolomeis A, Tomasetti C. Calcium-Dependent Networks in Dopamine–Glutamate Interaction: The Role of Postsynaptic Scaffolding Proteins. Mol Neurobiol 2012; 46:275-96. [DOI: 10.1007/s12035-012-8293-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 06/21/2012] [Indexed: 01/11/2023]
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Vasefi MS, Kruk JS, Liu H, Heikkila JJ, Beazely MA. Activation of 5-HT7 receptors increases neuronal platelet-derived growth factor β receptor expression. Neurosci Lett 2012; 511:65-9. [DOI: 10.1016/j.neulet.2012.01.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 01/04/2012] [Accepted: 01/05/2012] [Indexed: 10/14/2022]
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Zhao Q, Yokozawa T, Tsuneyama K, Tanaka K, Miyata T, Shibahara N, Matsumoto K. Chotosan (Diaoteng San)-induced improvement of cognitive deficits in senescence-accelerated mouse (SAMP8) involves the amelioration of angiogenic/neurotrophic factors and neuroplasticity systems in the brain. Chin Med 2011; 6:33. [PMID: 21943225 PMCID: PMC3189182 DOI: 10.1186/1749-8546-6-33] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 09/23/2011] [Indexed: 01/17/2023] Open
Abstract
Background Chotosan (CTS, Diaoteng San), a Kampo medicine (ie Chinese medicine) formula, is reportedly effective in the treatment of patients with cerebral ischemic insults. This study aims to evaluate the therapeutic potential of CTS in cognitive deficits and investigates the effects and molecular mechanism(s) of CTS on learning and memory deficits and emotional abnormality in an animal aging model, namely 20-week-old senescence-accelerated prone mice (SAMP8), with and without a transient ischemic insult (T2VO). Methods Age-matched senescence-resistant inbred strain mice (SAMR1) were used as control. SAMP8 received T2VO (T2VO-SAMP8) or sham operation (sham-SAMP8) at day 0. These SAMP8 groups were administered CTS (750 mg/kg, p.o.) or water daily for three weeks from day 3. Results Compared with the control group, both sham-SAMP8 and T2VO-SAMP8 groups exhibited cognitive deficits in the object discrimination and water maze tests and emotional abnormality in the elevated plus maze test. T2VO significantly exacerbated spatial cognitive deficits of SAMP8 elucidated by the water maze test. CTS administration ameliorated the cognitive deficits and emotional abnormality of sham- and T2VO-SAMP8 groups. Western blotting and immunohistochemical studies revealed a marked decrease in the levels of phosphorylated forms of neuroplasticity-related proteins, N-methyl-D-aspartate receptor 1 (NMDAR1), Ca2+/calmodulin-dependent protein kinase II (CaMKII), cyclic AMP responsive element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) in the frontal cortices of sham-SAMP8 and T2VO-SAMP8. Moreover, these animal groups showed significantly reduced levels of vasculogenesis/angiogenesis factors, vascular endothelial growth factor (VEGF), VEGF receptor type 2 (VEGFR2), platelet-derived growth factor-A (PDGF-A) and PDGF receptor α (PDGFRα). CTS treatment reversed the expression levels of these factors down-regulated in the brains of sham- and T2VO-SAMP8. Conclusion Recovery of impaired neuroplasticity system and VEGF/PDGF systems may play a role in the ameliorative effects of CTS on cognitive dysfunction caused by aging and ischemic insult.
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Affiliation(s)
- Qi Zhao
- Division of Medicinal Pharmacology, Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
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Cognitive and socio-emotional deficits in platelet-derived growth factor receptor-β gene knockout mice. PLoS One 2011; 6:e18004. [PMID: 21437241 PMCID: PMC3060876 DOI: 10.1371/journal.pone.0018004] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 02/17/2011] [Indexed: 12/18/2022] Open
Abstract
Platelet-derived growth factor (PDGF) is a potent mitogen. Extensive in vivo studies of PDGF and its receptor (PDGFR) genes have reported that PDGF plays an important role in embryogenesis and development of the central nervous system (CNS). Furthermore, PDGF and the β subunit of the PDGF receptor (PDGFR-β) have been reported to be associated with schizophrenia and autism. However, no study has reported on the effects of PDGF deletion on mice behavior. Here we generated novel mutant mice (PDGFR-β KO) in which PDGFR-β was conditionally deleted in CNS neurons using the Cre/loxP system. Mice without the Cre transgene but with floxed PDGFR-β were used as controls. Both groups of mice reached adulthood without any apparent anatomical defects. These mice were further examined by conducting several behavioral tests for spatial memory, social interaction, conditioning, prepulse inhibition, and forced swimming. The test results indicated that the PDGFR-β KO mice show deficits in all of these areas. Furthermore, an immunohistochemical study of the PDGFR-β KO mice brain indicated that the number of parvalbumin (calcium-binding protein)-positive (i.e., putatively γ-aminobutyric acid-ergic) neurons was low in the amygdala, hippocampus, and medial prefrontal cortex. Neurophysiological studies indicated that sensory-evoked gamma oscillation was low in the PDGFR-β KO mice, consistent with the observed reduction in the number of parvalbumin-positive neurons. These results suggest that PDGFR-β plays an important role in cognitive and socioemotional functions, and that deficits in this receptor may partly underlie the cognitive and socioemotional deficits observed in schizophrenic and autistic patients.
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Zai G, Zai C, Tiwari A, King N, Braithwaite J, van Tol H, Kennedy JL. Weak association of the platelet-derived growth factor beta (PDGFB) and PDGF receptor beta (PDGFRB) genes with schizophrenia and schizoaffective disorder. World J Biol Psychiatry 2011; 12:127-33. [PMID: 20950212 DOI: 10.3109/15622975.2010.520333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
UNLABELLED Schizophrenia is a severe neuropsychiatric disorder with diverse characterization of symptoms. Extensive research has been performed to elucidate the etiology of schizophrenia. One of the most convincing hypotheses comes from the dopaminergic system although none of the core genes has been consistently positive in association studies. OBJECTIVE In this investigation, we explored the possibility that the genes for platelet-derived growth factor beta (PDGFB) and its receptor (PDGFRB) might play an important role in the development of schizophrenia based on previous reports pointing to their ability to interact with the dopamine D(2)/D(4) and NMDA receptors as well as their role in neurite outgrowth. METHODS We investigated the association of variants around these genes with schizophrenia and schizoaffective disorder in 104 small nuclear families using the Sib-Transmission Disequilibrium Test (TDT-STDT). Furthermore, quantitative trait analysis using family-based association test was applied to determine possible association of age at onset (AAO). RESULTS Allele G in PDGFRB(rs758588) was associated with AAO (P=0.019). An over-transmission of allele T in PDGFB(rs130650) polymorphism (P=0.043) and an over-transmission of allele A in PDGFRB(rs6865659) polymorphism (P=0.046) were observed. Furthermore, the combined TDT-STDT yielded consistent results. CONCLUSION Overall, PDGFB and PDGFRB genes might play a role in the etiology of schizophrenia.
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Affiliation(s)
- Gwyneth Zai
- Neurogenetics Section, Centre for Addiction and Mental Health, Clarke Division, Toronto, Canada
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Gill RS, Hsiung MS, Sum CS, Lavine N, Clark SD, Van Tol HH. The dopamine D4 receptor activates intracellular platelet-derived growth factor receptor β to stimulate ERK1/2. Cell Signal 2010; 22:285-90. [DOI: 10.1016/j.cellsig.2009.09.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Accepted: 09/14/2009] [Indexed: 01/09/2023]
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Tsunekawa S, Ohi Y, Ishii Y, Sasahara M, Haji A. Hypoxic ventilatory response in platelet-derived growth factor receptor-beta-knockout mice. J Pharmacol Sci 2009; 110:270-5. [PMID: 19542682 DOI: 10.1254/jphs.09102fp] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The present study investigated whether the platelet-derived growth factor receptor (PDGFR)-beta-mediated mechanisms are involved in the hypoxic ventilatory response through modulating the N-methyl-D-aspartate (NMDA) function. The ventilatory changes during hypoxic challenge (10% O(2), 30 min) were measured plethysmographically in mice selectively lacking the PDGFR-beta in neurons (KO mice) and in control wild-type mice (WT mice) before and after blockade of NMDA receptors. In baseline breathing at rest, respiratory rate, tidal volume, and minute ventilation were similar between WT and KO mice. Hypoxia caused an increase of ventilation during the early period of exposure (an initial excitation), followed by a progressive decrease along with the exposure period (a late decline). The initial excitation occurred similarly in KO and WT mice, while the late decline was markedly attenuated in KO mice. Administration of an antagonist of NMDA receptors, dizocilpine (0.3 mg/kg, i.p.) decreased the initial excitation and hastened the late decline of hypoxic ventilatory response. Furthermore, the hypoxic ventilatory response in KO mice was indistinguishable from that in WT mice after blockade of NMDA receptors. The present study suggests that the PDGF-BB/PDGFR-beta signal axis contributes to the hypoxic ventilatory response by its inhibitory effect on the NMDA receptor-mediated function.
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Affiliation(s)
- Saori Tsunekawa
- Laboratory of Neuropharmacology, School of Pharmacy, Aichi Gakuin University, Japan
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16
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Beazely MA, Lim A, Li H, Trepanier C, Chen X, Sidhu B, Macdonald JF. Platelet-derived growth factor selectively inhibits NR2B-containing N-methyl-D-aspartate receptors in CA1 hippocampal neurons. J Biol Chem 2008; 284:8054-63. [PMID: 19106110 DOI: 10.1074/jbc.m805384200] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Platelet-derived growth factor (PDGF) beta receptor activation inhibits N-methyl-d-aspartate (NMDA)-evoked currents in hippocampal and cortical neurons via the activation of phospholipase Cgamma, PKC, the release of intracellular calcium, and a rearrangement of the actin cytoskeleton. In the hippocampus, the majority of NMDA receptors are heteromeric; most are composed of 2 NR1 subunits and 2 NR2A or 2 NR2B subunits. Using NR2B- and NR2A-specific antagonists, we demonstrate that PDGF-BB treatment preferentially inhibits NR2B-containing NMDA receptor currents in CA1 hippocampal neurons and enhances long-term depression in an NR2B subunit-dependent manner. Furthermore, treatment of hippocampal slices or cultures with PDGF-BB decreases the surface localization of NR2B but not of NR2A subunits. PDGFbeta receptors colocalize to a higher degree with NR2B subunits than with NR2A subunits. After neuronal injury, PDGFbeta receptors and PDGF-BB are up-regulated and PDGFbeta receptor activation is neuroprotective against glutamate-induced neuronal damage in cultured neurons. We demonstrate that the neuroprotective effects of PDGF-BB are occluded by the NR2B antagonist, Ro25-6981, and that PDGF-BB promotes NMDA signaling to CREB and ERK1/2. We conclude that PDGFbetaR signaling, by preferentially targeting NR2B receptors, provides an important mechanism for neuroprotection by growth factors in the central nervous system.
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Affiliation(s)
- Michael A Beazely
- Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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17
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Beazely MA, Weerapura M, MacDonald JF. Abelson tyrosine kinase links PDGFbeta receptor activation to cytoskeletal regulation of NMDA receptors in CA1 hippocampal neurons. Mol Brain 2008; 1:20. [PMID: 19077273 PMCID: PMC2651131 DOI: 10.1186/1756-6606-1-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Accepted: 12/12/2008] [Indexed: 01/12/2023] Open
Abstract
Background We have previously demonstrated that PDGF receptor activation indirectly inhibits N-methyl-D-aspartate (NMDA) currents by modifying the cytoskeleton. PDGF receptor ligand is also neuroprotective in hippocampal slices and cultured neurons. PDGF receptors are tyrosine kinases that control a variety of signal transduction pathways including those mediated by PLCγ. In fibroblasts Src and another non-receptor tyrosine kinase, Abelson kinase (Abl), control PDGF receptor regulation of cytoskeletal dynamics. The mechanism whereby PDGF receptor regulates cytoskeletal dynamics in central neurons remains poorly understood. Results Intracellular applications of active Abl, but not heat-inactivated Abl, decreased NMDA-evoked currents in isolated hippocampal neurons. This mimics the effects of PDGF receptor activation in these neurons. The Abl kinase inhibitor, STI571, blocked the inhibition of NMDA currents by Abl. We demonstrate that PDGF receptors can activate Abl kinase in hippocampal neurons via mechanisms similar to those observed previously in fibroblasts. Furthermore, PDGFβ receptor activation alters the subcellular localization of Abl. Abl kinase is linked to actin cytoskeletal dynamics in many systems. We show that the inhibition of NMDA receptor currents by Abl kinase is blocked by the inclusion of the Rho kinase inhibitor, Y-27632, and that activation of Abl correlates with an increase in ROCK tyrosine phosphorylation. Conclusion This study demonstrates that PDGFβ receptors act via an interaction with Abl kinase and Rho kinase to regulated cytoskeletal regulation of NMDA receptor channels in CA1 pyramidal neurons.
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18
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Kim HJ, Kim MH, Choe BK, Kim JW, Park JK, Cho AR, Bae H, Shin DH, Yim SV, Kwack K, Kwon YK, Chung JH. Genetic association between 5'-upstream single-nucleotide polymorphisms of PDGFRB and schizophrenia in a Korean population. Schizophr Res 2008; 103:201-8. [PMID: 18541413 DOI: 10.1016/j.schres.2008.04.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Revised: 04/15/2008] [Accepted: 04/20/2008] [Indexed: 10/22/2022]
Abstract
PDGFRB is located on chromosome 5q31-q32, a chromosomal region identified by linkage analyses to contain a susceptibility gene for schizophrenia (SCZ). Recent research has focused on the role of the N-methyl-d-aspartate (NMDA) receptor in the pathogenesis of SCZ. D4 dopamine receptor-mediated transactivation of the gene encoding platelet-derived growth factor receptor beta (PDGFRB) has immediate effects on synaptic neurotransmission via calcium-dependent inactivation of NMDA receptors. In this study, we investigate the association between the PDGFRB gene and SCZ in a Korean population. We screened 6 single-nucleotide polymorphisms (SNPs) in the 5'-upstream region of PDGFRB and conducted a case-control study of 381 SCZ patients and 752 controls. The genotype and haplotype frequencies of 3 of the 6 SNPs [SNP1 (g.-1924T>C, rs3756314), SNP3 (g.-1772A>G, rs3756312) and SNP4 (rs3756311, g.-1658G>A)] were significantly associated with SCZ [SNP1, corrected p=0.012 (co-dominant model), 0.002 (Dominant model), and 0.506 (Recessive model); SNP3 and 4, corrected p=0.003, 0.009, and 0.049]. Haplotype analysis also revealed that ht1 (CGG) and ht2 (TAA) were significantly associated with SCZ (ht1, corrected p=0.018, 0.340, and 0.010; ht2, corrected p=0.002, 0.009, and 0.016). Transient transfection in neuronal cells revealed that ht1 had higher luciferase activity than the vector alone. Furthermore, Pdgfrb expression was increased in the frontal cortex and hippocampus in a mouse model of SCZ induced by MK801. We conclude that SNPs of the 5'-upstream region of PDGFRB are associated with SCZ in a Korean population. These are weak positives that require future studies to confirm these results.
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Affiliation(s)
- Hak-Jae Kim
- Kohwang Medical Research Institute, School of Medicine, Department of Biology, Kyung Hee University, Seoul 130-701, Republic of Korea
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19
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Xu J, Weerapura M, Ali MK, Jackson MF, Li H, Lei G, Xue S, Kwan CL, Manolson MF, Yang K, Macdonald JF, Yu XM. Control of excitatory synaptic transmission by C-terminal Src kinase. J Biol Chem 2008; 283:17503-14. [PMID: 18445593 DOI: 10.1074/jbc.m800917200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The induction of long-term potentiation at CA3-CA1 synapses is caused by an N-methyl-d-aspartate (NMDA) receptordependent accumulation of intracellular Ca(2+), followed by Src family kinase activation and a positive feedback enhancement of NMDA receptors (NMDARs). Nevertheless, the amplitude of baseline transmission remains remarkably constant even though low frequency stimulation is also associated with an NMDAR-dependent influx of Ca(2+) into dendritic spines. We show here that an interaction between C-terminal Src kinase (Csk) and NMDARs controls the Src-dependent regulation of NMDAR activity. Csk associates with the NMDAR signaling complex in the adult brain, inhibiting the Src-dependent potentiation of NMDARs in CA1 neurons and attenuating the Src-dependent induction of long-term potentiation. Csk associates directly with Src-phosphorylated NR2 subunits in vitro. An inhibitory antibody for Csk disrupts this physical association, potentiates NMDAR mediated excitatory postsynaptic currents, and induces long-term potentiation at CA3-CA1 synapses. Thus, Csk serves to maintain the constancy of baseline excitatory synaptic transmission by inhibiting Src kinase-dependent synaptic plasticity in the hippocampus.
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Affiliation(s)
- Jindong Xu
- Faculty of Dentistry, University of Toronto, Toronto, Ontario M5G 1G6, Canada
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20
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Ohi Y, Ishii Y, Haji A, Noguchi S, Sasaoka T, Fujimori T, Nabeshima YI, Sasahara M, Hattori Y. Platelet-derived growth factor (PDGF)-BB inhibits AMPA receptor-mediated synaptic transmission via PDGF receptor-beta in murine nucleus tractus solitarius. Brain Res 2007; 1159:77-85. [PMID: 17573050 DOI: 10.1016/j.brainres.2007.05.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2007] [Revised: 05/14/2007] [Accepted: 05/14/2007] [Indexed: 11/26/2022]
Abstract
Although platelet-derived growth factor (PDGF)-BB activates PDGF receptor-beta (PDGFR-beta) and, in turn, inhibits the glutamate N-methyl-D-aspartate (NMDA) receptor function, whether PDGF-BB modulates the CNS function mediated by another glutamate receptors, alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors, remains poorly understood. Here we now report the inhibitory effect of PDGF-BB on the AMPA receptor function in the nucleus tractus solitarius (NTS) by using slice patch-clamp techniques. Excitatory postsynaptic currents (EPSCs) were evoked by electrical stimulation of the tractus solitarius in mouse NTS second-order neurons. EPSCs were nearly completely eliminated by CNQX but not by MK-801, implying mediation through non-NMDA receptors. PDGF-BB significantly decreased the amplitude of EPSCs without affecting the mean decay time constant. This inhibitory effect was transient and reversible after removing PDGF-BB. Furthermore, PDGF-BB significantly reduced the amplitude of AMPA-induced currents in NTS neurons, which showed that PDGF-BB could suppress the AMPA receptor-mediated excitatory input via the postsynaptic mechanism. The inhibitory effect of PDGF-BB on EPSCs was not observed in mutant mice with conditional deletion of the PDGFR-beta gene in neurons. Together, these studies suggest that the PDGF-B/PDGFR-beta axis inhibits the AMPA receptor-mediated synaptic transmission that comprises the major part of the primary afferent to the NTS second-order neuron. The detected inhibitory action may be involved in the CNS regulation of the respiratory response.
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Affiliation(s)
- Yoshiaki Ohi
- Department of Molecular and Medical Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan
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21
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Horne EA, Dell'Acqua ML. Phospholipase C is required for changes in postsynaptic structure and function associated with NMDA receptor-dependent long-term depression. J Neurosci 2007; 27:3523-34. [PMID: 17392468 PMCID: PMC6672111 DOI: 10.1523/jneurosci.4340-06.2007] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
NMDA receptor (NMDAR)-dependent hippocampal synaptic plasticity underlying learning and memory coordinately regulates dendritic spine structure and AMPA receptor (AMPAR) postsynaptic strength through poorly understood mechanisms. Induction of long-term depression (LTD) activates protein phosphatase 2B/calcineurin (CaN), leading to dendritic spine shrinkage through actin depolymerization and AMPAR depression through receptor dephosphorylation and internalization. The scaffold proteins A-kinase-anchoring protein 79/150 (AKAP79/150) and postsynaptic density 95 (PSD95) form a complex that controls the opposing actions of the cAMP-dependent protein kinase (PKA) and CaN in regulation of AMPAR phosphorylation. The AKAP79/150-PSD95 complex is disrupted in hippocampal neurons during LTD coincident with internalization of AMPARs, decreases in PSD95 levels, and loss of AKAP79/150 and PKA from spines. AKAP79/150 is targeted to spines through binding F-actin and the phospholipid phosphatidylinositol-(4,5)-bisphosphate (PIP2). Previous electrophysiological studies have demonstrated that inhibition of phospholipase C (PLC)-catalyzed hydrolysis of PIP2 inhibits NMDAR-dependent LTD; however, the signaling mechanisms that link PLC activation to alterations in dendritic spine structure and AMPAR function in LTD are unknown. We show here that NMDAR stimulation of PLC in cultured hippocampal neurons is necessary for AKAP79/150 loss from spines and depolymerization of spine actin. Importantly, we demonstrate that NMDAR activation of PLC is also necessary for decreases in spine PSD95 levels and AMPAR internalization. Thus, PLC signaling is required for structural and functional changes in spine actin, PSD scaffolding, and AMPAR trafficking underlying postsynaptic expression of LTD.
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Affiliation(s)
| | - Mark L. Dell'Acqua
- Department of Pharmacology
- Program in Neuroscience, School of Medicine, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
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22
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MacDonald JF, Jackson MF, Beazely MA. G protein-coupled receptors control NMDARs and metaplasticity in the hippocampus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:941-51. [PMID: 17261268 DOI: 10.1016/j.bbamem.2006.12.006] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Revised: 12/06/2006] [Accepted: 12/09/2006] [Indexed: 11/20/2022]
Abstract
Long-term potentiation (LTP) and long-term depression (LTD) are the major forms of functional synaptic plasticity observed at CA1 synapses of the hippocampus. The balance between LTP and LTD or "metaplasticity" is controlled by G-protein coupled receptors (GPCRs) whose signal pathways target the N-methyl-D-asparate (NMDA) subtype of excitatory glutamate receptor. We discuss the protein kinase signal cascades stimulated by Galphaq and Galphas coupled GPCRs and describe how control of NMDAR activity shifts the threshold for the induction of LTP.
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Affiliation(s)
- John F MacDonald
- Department of Physiology, University of Toronto, Toronto, ON, Canada.
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23
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Beazely MA, Tong A, Wei WL, Van Tol H, Sidhu B, MacDonald JF. D2-class dopamine receptor inhibition of NMDA currents in prefrontal cortical neurons is platelet-derived growth factor receptor-dependent. J Neurochem 2006; 98:1657-63. [PMID: 16879713 DOI: 10.1111/j.1471-4159.2006.04064.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
NMDA receptor function is modulated by both G-protein-coupled receptors and receptor tyrosine kinases. In acutely isolated rat hippocampal neurons, direct activation of the platelet-derived growth factor (PDGF) receptor or transactivation of the PDGF receptor by D4 dopamine receptors inhibits NMDA-evoked currents in a phospholipase C (PLC)-dependent manner. We have investigated further the ability of D2-class dopamine receptors to modulate NMDA-evoked currents in isolated rat prefrontal cortex (PFC). We have demonstrated that, similar to isolated hippocampal neurons, the application of PDGF-BB or quinpirole to isolated PFC neurons induces a slow-onset and long-lasting inhibition of NMDA-evoked currents. However, in contrast to hippocampal neurons, the inhibition of NMDA-evoked currents by quinpirole in PFC neurons is dependent upon D2/3, rather than D4, dopamine receptors. In PFC slices, application of both PDGF-BB and quinpirole induced a phosphorylation of the PDGF receptor at the PLCgamma binding and activation site, Tyr1021. The PDGF receptor kinase inhibitor, tyrphostin A9, and the D2/3 dopamine receptor antagonist, raclopride, inhibited quinpirole-induced Tyr1021 phosphorylation. These finding suggest that quinpirole treatment inhibits NMDAR signaling via PDGF receptor transactivation in both the hippocampus and the PFC, and that the effects of quinpirole in these regions are mediated by D4 and D2/3 dopamine receptors, respectively.
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Affiliation(s)
- Michael A Beazely
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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24
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Ishii Y, Oya T, Zheng L, Gao Z, Kawaguchi M, Sabit H, Matsushima T, Tokunaga A, Ishizawa S, Hori E, Nabeshima YI, Sasaoka T, Fujimori T, Mori H, Sasahara M. Mouse brains deficient in neuronal PDGF receptor-beta develop normally but are vulnerable to injury. J Neurochem 2006; 98:588-600. [PMID: 16805849 DOI: 10.1111/j.1471-4159.2006.03922.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Platelet-derived growth factors (PDGFs) and PDGF receptors (PDGFRs) are widely expressed in the mammalian CNS, though their functional significance remains unclear. The corresponding null-knockout mutations are lethal. Here, we developed novel mutant mice in which the gene encoding the beta subunit of PDGFR (PDGFR-beta) was genetically deleted in CNS neurons to elucidate the role of PDGFR-beta, particularly in the post-natal stage. Our mutant mice reached adulthood without apparent anatomical defects. In the mutant brain, immunohistochemical analyses showed that PDGFR-beta detected in neurons and in the cells in the subventricular zone of the lateral ventricle in wild-type mice was depleted, but PDGFR-beta detected in blood vessels remained unaffected. The cerebral damage after cryogenic injury was severely exacerbated in the mutants compared with controls. Furthermore, TdT-mediated dUTP-biotin nick end labeling (TUNEL)-positive neuronal cell death and lesion formation in the cerebral hemisphere were extensively exacerbated in our mutant mice after direct injection of NMDA without altered NMDA receptor expression. Our results clearly demonstrate that PDGFR-beta expressed in neurons protects them from cryogenic injury and NMDA-induced excitotoxicity.
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Affiliation(s)
- Yoko Ishii
- Department of Pathology, Faculty of Medicine, University of Toyama, Toyama, Japan
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25
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Affiliation(s)
- Victor A Levin
- Department of Neuro-Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, USA
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26
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Tseng HC, Dichter MA. Platelet-derived growth factor-BB pretreatment attenuates excitotoxic death in cultured hippocampal neurons. Neurobiol Dis 2005; 19:77-83. [PMID: 15837563 DOI: 10.1016/j.nbd.2004.11.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Revised: 07/14/2004] [Accepted: 11/16/2004] [Indexed: 10/25/2022] Open
Abstract
Neuronal excitotoxic death results from excess stimulation by elevated levels of extracellular glutamate acting on N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. While excitotoxicity is typically attenuated by using glutamate receptor antagonists, we report here that neuronal deaths induced directly by brief exposures to glutamate or NMDA were both attenuated by preincubation with platelet-derived growth factor-BB (PDGF-BB). The neuroprotection was concentration and time dependent; preincubation for at least 24 h with a minimum of 10 ng/mL of PDGF-BB was required for maximal neuroprotective effect. The NMDA receptor antagonist MK-801 also afforded partial protection, and when MK-801 was used with PDGF-BB, neuronal survival was comparable to that of untreated controls. When protection of inhibitory and excitatory neurons by PDGF treatment was compared, the excitatory neurons appeared to be selectively protected. The present results demonstrate that PDGF pretreatment can protect neurons from direct glutamate-induced excitotoxicity in vitro and suggests that PDGF might possibly function as a neuroprotective agent in potential therapeutic applications.
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Affiliation(s)
- Henry C Tseng
- David Mahoney Institute of Neurological Sciences, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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27
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Trantham-Davidson H, Neely LC, Lavin A, Seamans JK. Mechanisms underlying differential D1 versus D2 dopamine receptor regulation of inhibition in prefrontal cortex. J Neurosci 2005; 24:10652-9. [PMID: 15564581 PMCID: PMC5509068 DOI: 10.1523/jneurosci.3179-04.2004] [Citation(s) in RCA: 183] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Typically, D1 and D2 dopamine (DA) receptors exert opposing actions on intracellular signaling molecules and often have disparate physiological effects; however, the factors determining preferential activation of D1 versus D2 signaling are not clear. Here, in vitro patch-clamp recordings show that DA concentration is a critical determinant of D1 versus D2 signaling in prefrontal cortex (PFC). Low DA concentrations (<500 nm) enhance IPSCs via D1 receptors, protein kinase A, and cAMP. Higher DA concentrations (>1 microm) decrease IPSCs via the following cascade: D2-->G(i)-->platelet-derived growth factor receptor--> increase phospholipase C--> increase IP3--> increase Ca2+--> decrease dopamine and cAMP-regulated phosphoprotein-32--> increase protein phosphatase 1/2A--> decrease GABA(A). Blockade of any molecule in the D2-linked pathway reveals a D1-mediated increase in IPSCs, suggesting that D1 effects are occluded at higher DA concentrations by this D2-mediated pathway. Thus, DA concentration, by acting through separate signaling cascades, may determine the relative amount of cortical inhibition and thereby differentially regulate the tuning of cortical networks.
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Affiliation(s)
- Heather Trantham-Davidson
- Physiology and Neuroscience Department, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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28
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Wang C, Buck DC, Yang R, Macey TA, Neve KA. Dopamine D2 receptor stimulation of mitogen-activated protein kinases mediated by cell type-dependent transactivation of receptor tyrosine kinases. J Neurochem 2005; 93:899-909. [PMID: 15857393 DOI: 10.1111/j.1471-4159.2005.03055.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dopamine D2 receptor activation of extracellular signal-regulated kinases (ERKs) in non-neuronal human embryonic kidney 293 cells was dependent on transactivation of the platelet-derived growth factor (PDGF) receptor, as demonstrated by the effect of the PDGF receptor inhibitors tyrphostin A9 and AG 370 on quinpirole-induced phosphorylation of ERKs and by quinpirole-induced tyrosine phosphorylation of the PDGF receptor. In contrast, ectopically expressed D2 receptor or endogenous D2-like receptor activation of ERKs in NS20Y neuroblastoma cells, which express little or no PDGF receptor, or in rat neostriatal neurons was largely dependent on transactivation of the epidermal growth factor (EGF) receptor, as demonstrated using the EGF receptor inhibitor AG 1478 and by quinpirole-induced phosphorylation of the EGF receptor. The D2 receptor agonist quinpirole enhanced the coprecipitation of D2 and EGF receptors in NS20Y cells, suggesting that D2 receptor activation induced the formation of a macromolecular signaling complex that includes both receptors. Transactivation of the EGF receptor also involved the activity of a matrix metalloproteinase. Thus, although D2 receptor stimulation of ERKs in both cell lines was decreased by inhibitors of ERK kinase, Src-family protein tyrosine kinases, and serine/threonine protein kinases, D2-like receptors activated ERKs via transactivation of the EGF receptor in NS20Y neuroblastoma cells and rat embryonic neostriatal neurons, but via transactivation of the PDGF receptor in 293 cells.
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Affiliation(s)
- Chunhe Wang
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, 97239, USA
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29
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Egawa-Tsuzuki T, Ohno M, Tanaka N, Takeuchi Y, Uramoto H, Faigle R, Funa K, Ishii Y, Sasahara M. The PDGF B-chain is involved in the ontogenic susceptibility of the developing rat brain to NMDA toxicity. Exp Neurol 2004; 186:89-98. [PMID: 14980813 DOI: 10.1016/j.expneurol.2003.11.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2003] [Revised: 10/31/2003] [Accepted: 11/05/2003] [Indexed: 11/27/2022]
Abstract
Hypoxic-ischemic (H-I) injury to neonatal brains can cause a life-long neuronal deficit because of increased susceptibility in the neonatal period. Excitotoxicity due to overstimulation of the N-methyl-d-aspartate receptor (NMDAR) is assumed to be the basis of the injury. However, the ontogenic profile of the susceptibility does not directly correlate with the levels of NMDAR expression. Platelet-derived growth factor B-chain (PDGF-B) has been reported to protect neurons by suppressing the NMDA-evoked current and translocating the glutamate transporter to the cell membrane. Thus, we assessed the relationship between the susceptibility to H-I injury and the expression of PDGF-B in neonatal rat brain. PDGF-B infusion before and after an intrastriatal NMDA injection significantly reduced the size of the lesions in 7-day-old rats, when they are most susceptible and the neuronal expression of PDGF-B is low. Fourteen-day-old neonatal rats were found to be resistant to NMDA injury, even though NMDARs are expressed at high levels in the brain at this age. Inhibition of PDGF-B protein synthesis by antisense oligodeoxynucleotides increased the size of the NMDA-induced lesions up to 6-fold at postnatal day 14, when PDGF-B is expressed at high levels in neurons. These data suggest that PDGF-B is an important physiological modulator of NMDAR excitability in the developing brain, and that the balance between the expression of NMDAR and PDGF-B partly determines the ontogenic susceptibility to brain injury. Enhancement of the PDGF-B/receptor signal pathway might rescue neonatal brains at risk of H-I injury.
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30
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Shah BH, Catt KJ. GPCR-mediated transactivation of RTKs in the CNS: mechanisms and consequences. Trends Neurosci 2004; 27:48-53. [PMID: 14698610 DOI: 10.1016/j.tins.2003.11.003] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Bukhtiar H Shah
- Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA
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31
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Wong AHC, Van Tol HHM. The dopamine D4 receptors and mechanisms of antipsychotic atypicality. Prog Neuropsychopharmacol Biol Psychiatry 2003; 27:1091-9. [PMID: 14642969 DOI: 10.1016/j.pnpbp.2003.09.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The dopamine D4 receptor (D4) is a target for most common neuroleptic medications. After its initial discovery, it was found to possess the highest affinity of all dopamine receptor subtypes for the archetypical, atypical, antipsychotic clozapine. Nevertheless, initial clinical trials have not provided evidence that this receptor is a primary target for antipsychotic drugs. Considering the accumulated in vivo evidence that at least a subgroup of psychotic patients have altered dopamine signaling, all dopamine receptor subtypes likely contribute to the phenotypic expression of schizophrenia. New insights into the function of this receptor and its role in the modulation of excitatory signaling support the view that this dopamine receptor may affect attention and cognition. In this review, the authors outline some recent developments that provide insight into D4 receptor physiology, function and its possible relationship to schizophrenia treatment.
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Affiliation(s)
- Albert H C Wong
- Laboratory of Molecular Neurobiology, Centre for Addiction and Mental Health, University of Toronto, Toronto, ON, Canada M5T 1R8
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Kotecha SA, MacDonald JF. Signaling molecules and receptor transduction cascades that regulate NMDA receptor-mediated synaptic transmission. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2003; 54:51-106. [PMID: 12785285 DOI: 10.1016/s0074-7742(03)54003-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Suhas A Kotecha
- Department of Physiology, Faculty of Medicine, University of Toronto, Canadian Institute of Health Research Group, The Synapse, Toronto, Ontario, Canada M5S 1A8
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Abstract
G-protein-coupled receptors generate signals that promote gene transcription through the 'transactivation' of receptor tyrosine kinases (RTKs) and activation of the mitogen-activated protein kinase (MAPK) cascade -- a process that involves RTK autophosphorylation and endocytosis. Pioneering work now suggests that D4-dopamine-receptor-mediated transactivation of the platelet-derived growth factor beta receptor has immediate effects on synaptic neurotransmission via Ca(2+)-dependent inactivation of NMDA receptors. The demonstration of a physiological role for RTK transactivation in the CNS provides novel opportunities for understanding how aberrant dopamine signalling might contribute to cognitive and attention deficits associated with schizophrenia and attention-deficit hyperactivity disorder.
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Affiliation(s)
- Stephen S G Ferguson
- Cell Biology Research Group, Robarts Research Institute, Department of Physiology and Pharmacology, University of Western Ontario, 100 Perth Drive, PO Box 5015, London, Ontario, Canada N6A 5K8.
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Kotecha SA, Oak JN, Jackson MF, Perez Y, Orser BA, Van Tol HHM, MacDonald JF. A D2 class dopamine receptor transactivates a receptor tyrosine kinase to inhibit NMDA receptor transmission. Neuron 2002; 35:1111-22. [PMID: 12354400 DOI: 10.1016/s0896-6273(02)00859-0] [Citation(s) in RCA: 177] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Receptor tyrosine kinases (RTKs) are membrane spanning proteins with intrinsic kinase activity. Although these receptors are known to be involved in proliferation and differentiation of cells, their roles in regulating central synaptic transmission are largely unknown. In CA1 pyramidal neurons, activation of D2 class dopamine receptors depressed excitatory transmission mediated by the NMDA subtype of glutamate receptor. This depression resulted from the quinpirole-induced release of intracellular Ca(2+) and enhanced Ca(2+)-dependent inactivation of NMDA receptors. The dopamine receptor-mediated depression was dependent on the "transactivation" of PDGFRbeta. Therefore, RTK transactivation provides a novel mechanism of communication between dopaminergic and glutamatergic systems and might help to explain how reciprocal changes in these systems could be linked to the deficits in cognition, memory, and attention observed in schizophrenia and attention deficit hyperactivity disorder.
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Affiliation(s)
- Suhas A Kotecha
- Department of Physiology, Faculty of Medicine, University of Toronto, Ontario, Canada
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Abstract
The postsynaptic density (PSD) at excitatory dendritic synapses comprises a protein complex of glutamate receptors, scaffolding elements, and signaling enzymes. For example, NMDA receptors (NMDARs) are linked to several proteins in the PSD, such as PSD-95, and are also tethered via binding proteins such as alpha-actinin directly to filamentous actin of the cytoskeleton. Depolymerization of the cytoskeleton modulates the activity of NMDARs, and, in turn, strong activation of NMDARs can trigger depolymerization of actin. Myosin, the motor protein of muscular contraction and nonmuscle motility, is also associated with NMDARs and the PSD. We show here that constitutively active myosin light chain kinase (MLCK) enhances NMDAR-mediated whole-cell and synaptic currents in acutely isolated CA1 pyramidal and cultured hippocampal neurons, whereas inhibitors of MLCK depress these currents. This MLCK-dependent regulation was observed in cell-attached patches but was lost after excision to inside-out patches. Furthermore, the enhancement induced by constitutively active MLCK and the depression of MLCK inhibitors were eliminated after depolymerization of the cytoskeleton. NMDARs and MLCK did not colocalize in clusters on the dendrites of cultured hippocampal neurons, further indicating that the effects of MLCK are mediated indirectly via actomyosin. Our results suggest that MLCK enhances actomyosin contractility to either increase the membrane tension on NMDARs or to alter physical relationships between the actin cytoskeleton and the linker proteins of NMDARs.
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Wheldon LM, Nahorski SR, Willars GB. Inositol 1,4,5-trisphosphate-independent calcium signalling by platelet-derived growth factor in the human SH-SY5Y neuroblastoma cell. Cell Calcium 2001; 30:95-106. [PMID: 11440467 DOI: 10.1054/ceca.2001.0217] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In adherent SH-SY5Y human neuroblastoma cells, activation of G-protein-coupled muscarinic M3 receptors evoked a biphasic elevation of both intracellular [Ca(2+)] ([Ca(2+)]i) and inositol-1,4,5-trisphosphate (D-Ins(1,4,5)P3) mass. In both cases, temporal profiles consisted of rapid transient elevations followed by a decline to a lower, yet sustained level. In contrast, platelet-derived growth factor (PDGF), a receptor tyrosine kinase agonist acting via PDGF receptor b chains in these cells, elicited a slow and transient elevation of [Ca(2+)]i that returned to basal levels within 5 to 10 min with no evidence of inositol phosphate generation. Full responses for either receptor type required intracellular and extracellular Ca(2+) and mobilization of a shared thapsigargin-sensitive intracellular Ca(2+) store. Strategies that affected the ability of D-Ins(1,4,5)P3 to interact with the Ins(1,4,5)P3-receptor demonstrated an Ins(1,4,5)P3-dependency of the muscarinic receptor-mediated elevation of [Ca(2+)]i but showed that PDGF-mediated elevations of [Ca(2+)]i are Ins(1,4,5)P3-independent in these cells.
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Affiliation(s)
- L M Wheldon
- Department of Cell Physiology & Pharmacology, University of Leicester, UK.
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Li-Smerin Y, Levitan ES, Johnson JW. Free intracellular Mg(2+) concentration and inhibition of NMDA responses in cultured rat neurons. J Physiol 2001; 533:729-43. [PMID: 11410630 PMCID: PMC2278664 DOI: 10.1111/j.1469-7793.2001.t01-1-00729.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
1. Intracellular Mg(2+) (Mg(2+)(i)) blocks single-channel currents and modulates the gating kinetics of NMDA receptors. However, previous data suggested that Mg(2+)(i) inhibits whole-cell current less effectively than predicted from excised-patch measurements. We examined the basis of this discrepancy by testing three hypothetical explanations. 2. To test the first hypothesis, that control of free Mg(2+)(i) concentration ([Mg(2+)](i)) during whole-cell recording was inadequate, we measured [Mg(2+)](i) using mag-indo-1 microfluorometry. The [Mg(2+)](i) measured in cultured neurons during whole-cell recording was similar to the pipette [Mg(2+)] measured in vitro, suggesting that [Mg(2+)](i) was adequately controlled. 3. To test the second hypothesis, that open-channel block by Mg(2+)(i) was modified by patch excision, we characterised the effects of Mg(2+)(i) using cell-attached recordings. We found the affinity and voltage dependence of open-channel block by Mg(2+)(i) similar in cell-attached and outside-out patches. Thus, the difference between Mg(2+)(i) inhibition of whole-cell and of patch currents cannot be attributed to a difference in Mg(2+)(i) block of single-channel current. 4. The third hypothesis tested was that the effect of Mg(2+)(i) on channel gating was modified by patch excision. Results of cell-attached recording and modelling of whole-cell data suggest that the Mg(2+)(i)-induced stabilisation of the channel open state is four times weaker after patch excision than in intact cells. This differential effect of Mg(2+)(i) on channel gating explains why Mg(2+)(i) inhibits whole-cell NMDA responses less effectively than patch responses.
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Affiliation(s)
- Y Li-Smerin
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15260, USA
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Xiong Z, O'Hanlon D, Becker LE, Roder J, MacDonald JF, Marks A. Enhanced calcium transients in glial cells in neonatal cerebellar cultures derived from S100B null mice. Exp Cell Res 2000; 257:281-9. [PMID: 10837142 DOI: 10.1006/excr.2000.4902] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
S100B is the major low-affinity Ca(2+)-binding protein in astrocytes. In order to study the role of S100B in the maintenance of Ca(2+) homeostasis, we generated S100B null mice by a targeted inactivation of the S100B gene. Absence of S100B expression was demonstrated by Northern and Western blotting for S100B mRNA and protein, respectively, and immunoperoxidase staining of sections of various brain regions. S100B null mice were viable, fertile, and exhibited no overt behavioral abnormalities up to 12 months of age. On the basis of light microscopy and immunohistochemical staining, there were no discernable alterations in the distribution and morphology of astrocytes or neurons in sections of adult brains of these mice. Astrocytes in cerebellar cultures derived from 6-day-old S100B null mice exhibited enhanced Ca(2+) transients in response to treatment with KCl or caffeine. On the other hand, granule neurons, in the same cultures, exhibited normal Ca(2+) transients in response to treatment with KCl, caffeine, or N-methyl-d-aspartate. These results demonstrate a specific decrease in Ca(2+)-handling capacity in astrocytes derived from S100B null mice and suggest that S100B plays a role in the maintenance of Ca(2+) homeostasis in astrocytes.
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Affiliation(s)
- Z Xiong
- Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
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