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Kelly SB, Dean JM, Zahra VA, Dudink I, Thiel A, Polglase GR, Miller SL, Hooper SB, Bennet L, Gunn AJ, Galinsky R. Progressive inflammation reduces high-frequency EEG activity and cortical dendritic arborisation in late gestation fetal sheep. J Neuroinflammation 2023; 20:124. [PMID: 37226206 DOI: 10.1186/s12974-023-02805-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/15/2023] [Indexed: 05/26/2023] Open
Abstract
BACKGROUND Antenatal infection/inflammation is associated with disturbances in neuronal connectivity, impaired cortical growth and poor neurodevelopmental outcomes. The pathophysiological substrate that underpins these changes is poorly understood. We tested the hypothesis that progressive inflammation in late gestation fetal sheep would alter cortical neuronal microstructure and neural function assessed using electroencephalogram band power analysis. METHODS Fetal sheep (0.85 of gestation) were surgically instrumented for continuous electroencephalogram (EEG) recording and randomly assigned to repeated saline (control; n = 9) or LPS (0 h = 300 ng, 24 h = 600 ng, 48 h = 1200 ng; n = 8) infusions to induce inflammation. Sheep were euthanised 4 days after the first LPS infusion for assessment of inflammatory gene expression, histopathology and neuronal dendritic morphology in the somatosensory cortex. RESULTS LPS infusions increased delta power between 8 and 50 h, with reduced beta power from 18 to 96 h (P < 0.05 vs. control). Basal dendritic length, numbers of dendritic terminals, dendritic arborisation and numbers of dendritic spines were reduced in LPS-exposed fetuses (P < 0.05 vs. control) within the somatosensory cortex. Numbers of microglia and interleukin (IL)-1β immunoreactivity were increased in LPS-exposed fetuses compared with controls (P < 0.05). There were no differences in total numbers of cortical NeuN + neurons or cortical area between the groups. CONCLUSIONS Exposure to antenatal infection/inflammation was associated with impaired dendritic arborisation, spine number and loss of high-frequency EEG activity, despite normal numbers of neurons, that may contribute to disturbed cortical development and connectivity.
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Affiliation(s)
- Sharmony B Kelly
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - Justin M Dean
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Valerie A Zahra
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia
| | - Ingrid Dudink
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - Alison Thiel
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - Laura Bennet
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Robert Galinsky
- The Ritchie Centre, Hudson Institute of Medical Research, 27-31 Wright Street, Melbourne, VIC, 3168, Australia.
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia.
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Hao YF, Luo T, Lu ZY, Shen CY, Jiang JG. Targets and underlying mechanisms related to the sedative and hypnotic activities of saponins from Rhodiola rosea L. (crassulaceae). Food Funct 2021; 12:10589-10601. [PMID: 34585202 DOI: 10.1039/d1fo01178b] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Rhodiola rosea L. (Crassulaceae) are popularly used as a natural supplement for the treatment of insomnia and anxiety. Here, saponin extracts from R. rosea were investigated for their roles on relieving sleeplessness. The levels of neurotransmitters, hormones, and inflammation cytokines in plasma, and the expression of 5-hydroxytryptamine (5-HT), γ-aminobutyric acid (GABA), prostaglandin D2 (PGD2), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in the hypothalamus and hippocampus were detected using ELISA, RT-PCR, and western blotting. First, the butanol fraction extracted from R. rosea was collected as the total saponins (HJT-I), then a saponin-rich fraction (HJT-II) was obtained after the further purification of HJT-I. The saponin contents of HJT-I and HJT-II were 28.92% and 65.69%, respectively. Second, behavioral tests were performed and showed that both HJT-I and HJT-II could effectively reduce the duration of immobility in the tail suspension test, and shorten sleep latency and prolong the sleep duration time in the sodium barbital-induced sleeping test, with HJT-II better than HJT-I. Third, ELLISA results showed that the concentrations of GABA, 5-HT, norepinephrine (NA), PGD2, and IL-1β in plasma were significantly increased after HJT-I and HJT-II administration, while IL-6 was decreased. HJT-I and HJT-II also exhibited differential modulation of the receptors of 5-HT, GABA, PGD2, and IL-1β expression. In hypothalamus, HJT-II was more powerful than HJT-I in regulation of the GABAARα2, GABAARα3, and glutamic acid decarboxylase (GAD) 65/67 expression, as well as 5-HT2A and IL-1β. As for DPR and PGD2, HJT-II was more effective in the hippocampus. The efficacy of HJT-I was better than HJT-II at stimulating GABAARα2, GAD 65/67, 5-HT1A, and IL-1β expression in the hippocampus. In conclusion, the potential sedative and hypnotic effects of HJT-I and HJT-II may possibly be related to the serotonergic, GABAAergic, and immune systems, while the underlying mechanism of HJT-I and HJT-II differed from each other.
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Affiliation(s)
- Yun-Fang Hao
- College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China.
| | - Ting Luo
- College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China.
| | - Zhong-Yu Lu
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Chun-Yan Shen
- College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China. .,School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Jian-Guo Jiang
- College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China.
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Stemkowski PL, Bukhanova-Schulz N, Baldwin T, de Chaves EP, Smith PA. Are sensory neurons exquisitely sensitive to interleukin 1β? J Neuroimmunol 2021; 354:577529. [PMID: 33676084 DOI: 10.1016/j.jneuroim.2021.577529] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 02/21/2021] [Accepted: 02/21/2021] [Indexed: 11/18/2022]
Abstract
Peripheral nerve injury frequently evokes chronic neuropathic pain. This is initiated by a transient inflammatory response that leads to persistent excitation of dorsal root ganglion (DRG) neurons by inflammatory cytokines such as interleukin 1β(IL-1β). In non-neuronal cells such as lymphocytes, interleukin 1 exerts actions at attomolar (aM; 10-18 M) concentrations. We now report that DRG neurons in defined-medium, neuron-enriched culture display increased excitability following 5-6 d exposure of 1aM IL-1β. This response is mediated in part by type 1 interleukin receptors and involves decreased function of putative KCa1.1 channels. This finding provides new insights into the neuroimmune interactions responsible for neuropathic pain.
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Affiliation(s)
- Patrick L Stemkowski
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Nataliya Bukhanova-Schulz
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Troy Baldwin
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Elena Posse de Chaves
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Peter A Smith
- Neuroscience and Mental Health Institute and Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
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4
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Lorea-Hernández JJ, Camacho-Hernández NP, Peña-Ortega F. Interleukin 1-beta but not the interleukin-1 receptor antagonist modulates inspiratory rhythm generation in vitro. Neurosci Lett 2020; 734:134934. [PMID: 32259558 DOI: 10.1016/j.neulet.2020.134934] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/24/2020] [Accepted: 03/25/2020] [Indexed: 10/24/2022]
Abstract
Interleukin 1-beta (IL-1β) is a cytokine that modulates breathing when applied systemically or directly into the brain. IL-1β is expressed, along with its receptors, in IL-1β-sensitive respiratory-related circuits, which likely include the inspiratory rhythm generator (the preBötzinger complex, preBötC). Thus, considering that IL-1β might directly modulate preBötC function, we tested whether IL-1β and its endogenous antagonist IL1Ra modulate inspiratory rhythm generation in the brainstem slice preparation containing the preBötC. We found that IL-1β reduces, in a concentration-dependent manner, the amplitude of the fictive inspiratory rhythm generated by the preBötC, which is prevented by IL1Ra. Only a negligible effect on the rhythm frequency was observed at one of the concentrations tested (10 ng/mL). In sum, these findings indicate that IL-1β modulates respiratory rhythm generation. In contrast, IL1Ra did not produce a major effect but slightly increased burst amplitude regularity of the fictive respiratory rhythm. Our findings show that IL-1β modulates breathing by directly modulating the inspiratory rhythm generation. This modulation could contribute to the respiratory response to inflammation in health and disease.
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Affiliation(s)
- Jonathan Julio Lorea-Hernández
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, Qro, 76230, México
| | - Neira Polet Camacho-Hernández
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, Qro, 76230, México
| | - Fernando Peña-Ortega
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, Qro, 76230, México.
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Shen CY, Wan L, Zhu JJ, Jiang JG. Targets and underlying mechanisms related to the sedative and hypnotic activities of saponin extracts from semen Ziziphus jujube. Food Funct 2020; 11:3895-3903. [PMID: 32407431 DOI: 10.1039/d0fo00098a] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Semen Ziziphus jujube (SZJ) has been widely consumed because it is recognized as edible in China to treat insomnia disorders. However, the underlying mechanisms and potential therapeutic targets remain obscure. SZJ-I and SZJ-II with a saponin content of 52.10% and 75.20%, respectively, were extracted from SZJ. LC-MS analysis presented quite different chemical profiles of SZJ-I and SZJ-II. Mice with p-chlorophenylalanine (PCPA)-induced insomnia were used to comparatively and systematically test the sedative-hypnotic activities of SZJ-I and SZJ-II. In vivo behavioral tests revealed that SZJ-I and SZJ-II significantly shortened the immobility time and potentiated sodium pentobarbital-induced sleep. SZJ-II with a higher saponin content showed greater potency than SZJ-I. SZJ-I and SZJ-II also protected against PCPA-triggered neuropathological damages in the brain. Concentrations of 5-hydroxytryptamine (5-HT), dopamine (DA), noradrenaline (NE), glutamate (Glu), interleukin-6 (IL-6), interleukin-1β (IL-1β), nitric oxide (NO) and prostaglandin D2 (PGD2) in plasma were significantly affected by SZJ-I and SZJ-II application. SZJ-I and SZJ-II also exhibited differential modulation of 5-hydroxytryptamine 1A (5-HT1A), 5-hydroxytryptamine 2A (5-HT2A), GABAA receptor α2 (GABAARα2), GABAA receptor α3 (GABAARα3), glutamic acid decarboxylase (GAD) 65/67, IL-6 and IL-1β expression in the hypothalamus and hippocampus. SZJ-I and SZJ-II might exert excellent sedative-hypnotic effects through multiple mechanisms that worked simultaneously. SZJ-I and especially SZJ-II are promising candidates for relieving insomnia.
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Affiliation(s)
- Chun-Yan Shen
- College of Food and Bioengineering, South China University of Technology, Guangzhou, 510640, China.
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Galinsky R, Dhillon SK, Dean JM, Davidson JO, Lear CA, Wassink G, Nott F, Kelly SB, Fraser M, Yuill C, Bennet L, Gunn AJ. Tumor necrosis factor inhibition attenuates white matter gliosis after systemic inflammation in preterm fetal sheep. J Neuroinflammation 2020; 17:92. [PMID: 32293473 PMCID: PMC7087378 DOI: 10.1186/s12974-020-01769-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 03/09/2020] [Indexed: 12/21/2022] Open
Abstract
Background Increased circulating levels of tumor necrosis factor (TNF) are associated with greater risk of impaired neurodevelopment after preterm birth. In this study, we tested the hypothesis that systemic TNF inhibition, using the soluble TNF receptor Etanercept, would attenuate neuroinflammation in preterm fetal sheep exposed to lipopolysaccharide (LPS). Methods Chronically instrumented preterm fetal sheep at 0.7 of gestation were randomly assigned to receive saline (control; n = 7), LPS infusion (100 ng/kg i.v. over 24 h then 250 ng/kg/24 h for 96 h plus 1 μg LPS boluses at 48, 72, and 96 h, to induce inflammation; n = 8) or LPS plus two i.v. infusions of Etanercept (2 doses, 5 mg/kg infused over 30 min, 48 h apart) started immediately before LPS-exposure (n = 8). Sheep were killed 10 days after starting infusions, for histology. Results LPS boluses were associated with increased circulating TNF, interleukin (IL)-6 and IL-10, electroencephalogram (EEG) suppression, hypotension, tachycardia, and increased carotid artery perfusion (P < 0.05 vs. control). In the periventricular and intragyral white matter, LPS exposure increased gliosis, TNF-positive cells, total oligodendrocytes, and cell proliferation (P < 0.05 vs control), but did not affect myelin expression or numbers of neurons in the cortex and subcortical regions. Etanercept delayed the rise in circulating IL-6, prolonged the increase in IL-10 (P < 0.05 vs. LPS), and attenuated EEG suppression, hypotension, and tachycardia after LPS boluses. Histologically, Etanercept normalized LPS-induced gliosis, and increase in TNF-positive cells, proliferation, and total oligodendrocytes. Conclusion TNF inhibition markedly attenuated white matter gliosis but did not affect mature oligodendrocytes after prolonged systemic inflammation in preterm fetal sheep. Further studies of long-term brain maturation are now needed.
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Affiliation(s)
- Robert Galinsky
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand.,The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Simerdeep K Dhillon
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Justin M Dean
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Joanne O Davidson
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Christopher A Lear
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Guido Wassink
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Fraser Nott
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Sharmony B Kelly
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Mhoyra Fraser
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Caroline Yuill
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Laura Bennet
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand
| | - Alistair Jan Gunn
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private bag 92019, Auckland, 1023, New Zealand.
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7
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Chaskiel L, Bristow AD, Bluthé RM, Dantzer R, Blomqvist A, Konsman JP. Interleukin-1 reduces food intake and body weight in rat by acting in the arcuate hypothalamus. Brain Behav Immun 2019; 81:560-573. [PMID: 31310797 DOI: 10.1016/j.bbi.2019.07.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 07/12/2019] [Accepted: 07/12/2019] [Indexed: 12/19/2022] Open
Abstract
A reduction in food intake is commonly observed after bacterial infection, a phenomenon that can be reproduced by peripheral administration of Gram-negative bacterial lipopolysaccharide (LPS) or interleukin-1beta (IL-1β), a pro-inflammatory cytokine released by LPS-activated macrophages. The arcuate nucleus of the hypothalamus (ARH) plays a major role in food intake regulation and expresses IL-1 type 1 receptor (IL-1R1) mRNA. In the present work, we tested the hypothesis that IL-1R1 expressing cells in the ARH mediate IL-1β and/or LPS-induced hypophagia in the rat. To do so, we developed an IL-1β-saporin conjugate, which eliminated IL-R1-expressing neurons in the hippocampus, and micro-injected it into the ARH prior to systemic IL-1β and LPS administration. ARH IL-1β-saporin injection resulted in loss of neuropeptide Y-containing cells and attenuated hypophagia and weight loss after intraperitoneal IL-1β, but not LPS, administration. In conclusion, the present study shows that ARH NPY-containing neurons express functional IL-1R1s that mediate peripheral IL-1β-, but not LPS-, induced hypophagia. Our present and previous findings indicate that the reduction of food intake after IL-1β and LPS are mediated by different neural pathways.
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Affiliation(s)
- Léa Chaskiel
- Psychoneuroimmunology, Nutrition and Genetics, UMR CNRS 5226-INRA 1286, University of Bordeaux, 33076 Bordeaux, France
| | - Adrian D Bristow
- National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK
| | - Rose-Marie Bluthé
- Psychoneuroimmunology, Nutrition and Genetics, UMR CNRS 5226-INRA 1286, University of Bordeaux, 33076 Bordeaux, France
| | - Robert Dantzer
- Department of Symptom Research, MD Anderson Cancer Center, The University of Texas, Houston, TX 770030, USA
| | - Anders Blomqvist
- Division of Neurobiology, Department of Clinical and Experimental Medicine, Faculty of Medicine and Health Sciences, Linköping University, S-581 85 Linköping, Sweden
| | - Jan Pieter Konsman
- UMR CNRS 5287 Aquitaine Institute for Integrative and Cognitive Neuroscience, University of Bordeaux, 33076 Bordeaux, France.
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Giacco V, Panattoni G, Medelin M, Bonechi E, Aldinucci A, Ballerini C, Ballerini L. Cytokine inflammatory threat, but not LPS one, shortens GABAergic synaptic currents in the mouse spinal cord organotypic cultures. J Neuroinflammation 2019; 16:127. [PMID: 31238967 PMCID: PMC6593520 DOI: 10.1186/s12974-019-1519-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 06/11/2019] [Indexed: 01/02/2023] Open
Abstract
Background Synaptic dysfunction, named synaptopathy, due to inflammatory status of the central nervous system (CNS) is a recognized factor potentially underlying both motor and cognitive dysfunctions in neurodegenerative diseases. To gain knowledge on the mechanistic interplay between local inflammation and synapse changes, we compared two diverse inflammatory paradigms, a cytokine cocktail (CKs; IL-1β, TNF-α, and GM-CSF) and LPS, and their ability to tune GABAergic current duration in spinal cord cultured circuits. Methods We exploit spinal organotypic cultures, single-cell electrophysiology, immunocytochemistry, and confocal microscopy to explore synaptic currents and resident neuroglia reactivity upon CK or LPS incubation. Results Local inflammation in slice cultures induced by CK or LPS stimulations boosts network activity; however, only CKs specifically reduced GABAergic current duration. We pharmacologically investigated the contribution of GABAAR α-subunits and suggested that a switch of GABAAR α1-subunit might have induced faster GABAAR decay time, weakening the inhibitory transmission. Conclusions Lower GABAergic current duration could contribute to providing an aberrant excitatory transmission critical for pre-motor circuit tasks and represent a specific feature of a CK cocktail able to mimic an inflammatory reaction that spreads in the CNS. Our results describe a selective mechanism that could be triggered during specific inflammatory stress. Electronic supplementary material The online version of this article (10.1186/s12974-019-1519-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Vincenzo Giacco
- International School for Advanced Studies (SISSA/ISAS), 34136, Trieste, Italy.,Present address: Wolfson Centre for Age Related Disease, King's College London, Guy's Campus, London, SE1 1UL, UK
| | - Giulia Panattoni
- International School for Advanced Studies (SISSA/ISAS), 34136, Trieste, Italy
| | - Manuela Medelin
- Department of Life Sciences, University of Trieste, 34127, Trieste, Italy
| | - Elena Bonechi
- Department NEUROFARBA, University of Florence, 50139, Florence, Italy
| | | | - Clara Ballerini
- Dipartimento di Medicina Sperimentale e Clinica, University of Florence, 50139, Florence, Italy.
| | - Laura Ballerini
- International School for Advanced Studies (SISSA/ISAS), 34136, Trieste, Italy.
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Pretreatment Cancer-Related Cognitive Impairment-Mechanisms and Outlook. Cancers (Basel) 2019; 11:cancers11050687. [PMID: 31100985 PMCID: PMC6562730 DOI: 10.3390/cancers11050687] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 05/06/2019] [Accepted: 05/14/2019] [Indexed: 12/25/2022] Open
Abstract
Cognitive changes are common in patients with active cancer and during its remission. This has largely been blamed on therapy-related toxicities and diagnosis-related stress, with little attention paid to the biological impact of cancer itself. A plethora of clinical studies demonstrates that cancer patients experience cognitive impairment during and after treatment. However, recent studies show that a significant portion of patients with non-central nervous system (CNS) tumors experience cognitive decline prior to treatment, suggesting a role for tumor-derived factors in modulating cognition and behavior. Cancer-related cognitive impairment (CRCI) negatively impacts a patient’s quality of life, reduces occupational and social functioning, and increases morbidity and mortality. Furthermore, patients with cancer cachexia frequently experience a stark neurocognitive decline, suggesting peripheral tumors exert an enduring toll on the brain during this chronic paraneoplastic syndrome. However, the scarcity of research on cognitive impairment in non-CNS cancers makes it difficult to isolate psychosocial, genetic, behavioral, and pathophysiological factors in CRCI. Furthermore, clinical models of CRCI are frequently confounded by complicated drug regimens that inherently affect neurocognitive processes. The severity of CRCI varies considerably amongst patients and highlights its multifactorial nature. Untangling the biological aspects of CRCI from genetic, psychosocial, and behavioral factors is non-trivial, yet vital in understanding the pathogenesis of CRCI and discovering means for therapeutic intervention. Recent evidence demonstrating the ability of peripheral tumors to alter CNS pathways in murine models is compelling, and it allows researchers to isolate the underlying biological mechanisms from the confounding psychosocial stressors found in the clinic. This review summarizes the state of the science of CRCI independent of treatment and focuses on biological mechanisms in which peripheral cancers modulate the CNS.
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Civciristov S, Halls ML. Signalling in response to sub-picomolar concentrations of active compounds: Pushing the boundaries of GPCR sensitivity. Br J Pharmacol 2019; 176:2382-2401. [PMID: 30801691 DOI: 10.1111/bph.14636] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 02/04/2019] [Accepted: 02/11/2019] [Indexed: 12/22/2022] Open
Abstract
There is evidence for ultra-sensitive responses to active compounds at concentrations below picomolar levels by proteins and receptors found in species ranging from bacteria to mammals. We have recently shown that such ultra-sensitivity is also demonstrated by a wide range of prototypical GPCRs, and we have determined the molecular mechanisms behind these responses for three family A GPCRs: the relaxin receptor, RXFP1; the β2 -adrenoceptor; and the M3 muscarinic ACh receptor. Interestingly, there are reports of similar ultra-sensitivity by more than 15 human GPCR families, in addition to other human receptors and channels. These occur through a diverse range of signalling pathways and produce modulation of important physiological processes, including neuronal transmission, chemotaxis, gene transcription, protein/ion uptake and secretion, muscle contraction and relaxation, and phagocytosis. Here, we summarise the accumulating evidence of ultra-sensitive receptor signalling to show that this is a common, though currently underappreciated, property of GPCRs. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc.
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Affiliation(s)
- Srgjan Civciristov
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Michelle L Halls
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
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11
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Anaeigoudari A, Norouzi F, Abareshi A, Beheshti F, Aaghaei A, Shafei MN, Gholamnezhad Z, Hosseini M. Protective effects of Nigella sativa on synaptic plasticity impairment induced by lipopolysaccharide. VETERINARY RESEARCH FORUM : AN INTERNATIONAL QUARTERLY JOURNAL 2018; 9:27-33. [PMID: 29719661 PMCID: PMC5913558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 11/07/2017] [Indexed: 10/28/2022]
Abstract
In the present study the protective effect of Nigella sativa (N. sativa) on synaptic plasticity impairment induced by lipopolysaccharide (LPS) in rats was investigated. Fifty-eight rats were grouped and treated as follows: 1) control (saline), 2) LPS, 3) LPS-N. sativa, and 4) N. sativa. In a Morris water maze test, the escape latency and traveled path to find the platform as well as time spent and the traveled distance in target quadrant (Q1) were measured. Long term potentiation (LTP) from CA1 area of hippocampus followed by high frequency stimulation to Schafer collateral was studied and slope, slope 10-90% and amplitude of field excitatory field potential (fEPSP) were calculated. The escape latency and traveled path in LPS group were significantly higher than those in the control group while, in LPS-N. sativa group these parameters were significantly lower than those in LPS group. The rats in LPS group spent less time and traveled shorter distance in Q1 than the rats in the control group while, in LPS-N. sativa group the rats spent more time and traveled longer distance than the rats in LPS group. LPS significantly decreased slope, slope 10-90% and amplitude of fEPSP while, in LPS-N. sativa group these parameters increased compared to LPS group. The results indicated that the hydro-alcohol extract of N. sativa protected against synaptic plasticity and spatial learning and memory impairment induced by LPS in rats.
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Affiliation(s)
- Akbar Anaeigoudari
- Department of Physiology, School of Medicine, Jiroft University of Medical Sciences, Jiroft, Iran;
| | - Fatemeh Norouzi
- Department of Physiology, Esfarayan Faculty of Medical Sciences, Esfarayan, Iran;
| | - Azam Abareshi
- Pharmacological Research Center of Medicinal Plants, Mashhad University of Medical Sciences, Mashhad, Iran;
| | - Farimah Beheshti
- Department of Basic Sciences and Neuroscience Research Center, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran; ,Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
| | - Azita Aaghaei
- Pharmacological Research Center of Medicinal Plants, Mashhad University of Medical Sciences, Mashhad, Iran;
| | - Mohammad Naser Shafei
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran;
| | - Zahra Gholamnezhad
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran;
| | - Mahmoud Hosseini
- Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.,Correspondence: Mahmoud Hosseini. PhD Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
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12
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Borniger JC, Cisse YM, Surbhi, Nelson RJ. Reciprocal Regulation of Circadian Rhythms and Immune Function. CURRENT SLEEP MEDICINE REPORTS 2017. [DOI: 10.1007/s40675-017-0070-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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13
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Hutson LW, Lebonville CL, Jones ME, Fuchs RA, Lysle DT. Interleukin-1 signaling in the basolateral amygdala is necessary for heroin-conditioned immunosuppression. Brain Behav Immun 2017; 62:171-179. [PMID: 28131792 PMCID: PMC5828772 DOI: 10.1016/j.bbi.2017.01.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 01/14/2017] [Accepted: 01/23/2017] [Indexed: 12/22/2022] Open
Abstract
Heroin administration suppresses the production of inducible nitric oxide (NO), as indicated by changes in splenic inducible nitric oxide synthase (iNOS) and plasma nitrate/nitrite. Since NO is a measure of host defense against infection and disease, this provides evidence that heroin can increase susceptibility to pathogens by directly interacting with the immune system. Previous research in our laboratory has demonstrated that these immunosuppressive effects of heroin can also be conditioned to environmental stimuli by repeatedly pairing heroin administration with a unique environmental context. Re-exposure to a previously drug-paired context elicits immunosuppressive effects similar to heroin administration alone. In addition, our laboratory has reported that the basolateral amygdala (BLA) and medial nucleus accumbens shell (mNAcS) are critical neural substrates that mediate this conditioned effect. However, our understanding of the contributing mechanisms within these brain regions is limited. It is known that the cytokine interleukin-1 (IL-1) plays an important role in learning and memory. In fact, our laboratory has demonstrated that inhibition of IL-1β expression in the dorsal hippocampus (DH) prior to re-exposure to a heroin-paired context prevents the suppression of measures of NO production. Therefore, the present studies sought to further investigate the role of IL-1 in heroin-conditioned immunosuppression. Blockade of IL-1 signaling in the BLA, but not in the caudate putamen or mNAcS, using IL-1 receptor antagonist (IL-1Ra) attenuated heroin-conditioned immunosuppression of NO production as measured by plasma nitrate/nitrite and iNOS mRNA expression in spleen tissue. Taken together, these findings suggest that IL-1 signaling in the BLA is necessary for the expression of heroin-conditioned immunosuppression of NO production and may be a target for interventions that normalize immune function in heroin users and patient populations exposed to opiate regimens.
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Affiliation(s)
- Lee W Hutson
- University of North Carolina at Chapel Hill, Department of Psychology and Neuroscience, Chapel Hill, NC, USA
| | - Christina L Lebonville
- University of North Carolina at Chapel Hill, Department of Psychology and Neuroscience, Chapel Hill, NC, USA
| | - Meghan E Jones
- University of North Carolina at Chapel Hill, Department of Psychology and Neuroscience, Chapel Hill, NC, USA
| | - Rita A Fuchs
- Washington State University, College of Veterinary Medicine, Department of Integrative Physiology and Neuroscience, Pullman, WA, USA
| | - Donald T Lysle
- University of North Carolina at Chapel Hill, Department of Psychology and Neuroscience, Chapel Hill, NC, USA.
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14
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Almeida CMOD, Malheiro A. Sleep, immunity and shift workers: A review. ACTA ACUST UNITED AC 2016; 9:164-168. [PMID: 28123655 PMCID: PMC5241621 DOI: 10.1016/j.slsci.2016.10.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 10/15/2016] [Accepted: 10/24/2016] [Indexed: 12/26/2022]
Abstract
To date, shift workers represent between 15% and 25% of the modern day workforce. Work time poses a great challenge to workers as it requires that they balance productivity and sleep time between shifts. As a result, these workers experience chronic sleep deprivation with increased fatigue and drowsiness due to this sleep deprivation. The impact of this kind of work on the immune system is not yet known. We conducted a literature review with the aim of evaluating articles on this specific type of work's effects on sleep and immunity.
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Affiliation(s)
- Carlos Mauricio Oliveira de Almeida
- Department of Neurology of the State University of Amazonas-UEA
- Correspondence to: Universidade Estadual do Amazonas-UEA, rua Carvalho Leal, no.1777, CEP, 3ª. andar., 69000-000 Manaus, Amazonas, Brasil.
| | - Adriana Malheiro
- Department of Immunolgy of the Federal University of Amazonas-UFAM, Brazil
- Hematology and Hemotherapy Foundation of Amazonas, HEMOAM, Brazil
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15
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Konermann A, Van Dyke T, Kantarci A, Jäger A. GABAB Receptors as Modulating Target for Inflammatory Responses of the Periodontal Ligament. Cell Mol Neurobiol 2016; 37:1067-1076. [DOI: 10.1007/s10571-016-0439-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 10/22/2016] [Indexed: 12/17/2022]
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Lipopolysaccharide-Induced Spatial Memory and Synaptic Plasticity Impairment Is Preventable by Captopril. Adv Med 2016; 2016:7676512. [PMID: 27830176 PMCID: PMC5088279 DOI: 10.1155/2016/7676512] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 08/20/2016] [Accepted: 09/22/2016] [Indexed: 11/17/2022] Open
Abstract
Introduction. Renin-angiotensin system has a role in inflammation and also is involved in many brain functions such as learning, memory, and emotion. Neuroimmune factors have been proposed as the contributors to the pathogenesis of memory impairments. In the present study, the effect of captopril on spatial memory and synaptic plasticity impairments induced by lipopolysaccharide (LPS) was investigated. Methods. The rats were divided and treated into control (saline), LPS (1 mg/kg), LPS-captopril (LPS-Capto; 50 mg/kg captopril before LPS), and captopril groups (50 mg/kg) before saline. Morris water maze was done. Long-term potentiation (LTP) from CA1 area of hippocampus was assessed by 100 Hz stimulation in the ipsilateral Schaffer collateral pathway. Results. In the LPS group, the spent time and traveled path to reach the platform were longer than those in the control, while, in the LPS-Capto group, they were shorter than those in the LPS group. Moreover, the slope and amplitude of field excitatory postsynaptic potential (fEPSP) decreased in the LPS group, as compared to the control group, whereas, in the LPS-Capto group, they increased compared to the LPS group. Conclusion. The results of the present study showed that captopril improved the LPS-induced memory and LTP impairments induced by LPS in rats. Further investigations are required in order to better understand the exact responsible mechanism(s).
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Eimerbrink M, White J, Pendry R, Hodges S, Sadler L, Wiles J, Weintraub M, Chumley M, Boehm G. Administration of the inverse benzodiazepine agonist MRK-016 rescues acquisition and memory consolidation following peripheral administration of bacterial endotoxin. Behav Brain Res 2015; 288:50-3. [DOI: 10.1016/j.bbr.2015.03.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 02/23/2015] [Accepted: 03/22/2015] [Indexed: 12/17/2022]
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Thakkar MM, Sharma R, Sahota P. Alcohol disrupts sleep homeostasis. Alcohol 2015; 49:299-310. [PMID: 25499829 DOI: 10.1016/j.alcohol.2014.07.019] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2014] [Revised: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 01/14/2023]
Abstract
Alcohol is a potent somnogen and one of the most commonly used "over the counter" sleep aids. In healthy non-alcoholics, acute alcohol decreases sleep latency, consolidates and increases the quality (delta power) and quantity of NREM sleep during the first half of the night. However, sleep is disrupted during the second half. Alcoholics, both during drinking periods and during abstinences, suffer from a multitude of sleep disruptions manifested by profound insomnia, excessive daytime sleepiness, and altered sleep architecture. Furthermore, subjective and objective indicators of sleep disturbances are predictors of relapse. Finally, within the USA, it is estimated that societal costs of alcohol-related sleep disorders exceeds $18 billion. Thus, although alcohol-associated sleep problems have significant economic and clinical consequences, very little is known about how and where alcohol acts to affect sleep. In this review, we have described our attempts to unravel the mechanism of alcohol-induced sleep disruptions. We have conducted a series of experiments using two different species, rats and mice, as animal models. We performed microdialysis, immunohistochemical, pharmacological, sleep deprivation and lesion studies which suggest that the sleep-promoting effects of alcohol may be mediated via alcohol's action on the mediators of sleep homeostasis: adenosine (AD) and the wake-promoting cholinergic neurons of the basal forebrain (BF). Alcohol, via its action on AD uptake, increases extracellular AD resulting in the inhibition of BF wake-promoting neurons. Since binge alcohol consumption is a highly prevalent pattern of alcohol consumption and disrupts sleep, we examined the effects of binge drinking on sleep-wakefulness. Our results suggest that disrupted sleep homeostasis may be the primary cause of sleep disruption observed following binge drinking. Finally, we have also shown that sleep disruptions observed during acute withdrawal, are caused due to impaired sleep homeostasis. In conclusion, we suggest that alcohol may disrupt sleep homeostasis to cause sleep disruptions.
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Affiliation(s)
- Mahesh M Thakkar
- Harry S. Truman Memorial Veterans Hospital, Columbia, MO 65201, USA; Department of Neurology, University of Missouri, Columbia, MO 65201, USA.
| | - Rishi Sharma
- Harry S. Truman Memorial Veterans Hospital, Columbia, MO 65201, USA; Department of Neurology, University of Missouri, Columbia, MO 65201, USA
| | - Pradeep Sahota
- Harry S. Truman Memorial Veterans Hospital, Columbia, MO 65201, USA; Department of Neurology, University of Missouri, Columbia, MO 65201, USA
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19
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Lear CA, Davidson JO, Booth LC, Wassink G, Galinsky R, Drury PP, Fraser M, Bennet L, Gunn AJ. Biphasic changes in fetal heart rate variability in preterm fetal sheep developing hypotension after acute on chronic lipopolysaccharide exposure. Am J Physiol Regul Integr Comp Physiol 2014; 307:R387-95. [PMID: 24944248 DOI: 10.1152/ajpregu.00110.2014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Perinatal exposure to infection is highly associated with adverse outcomes. Experimentally, acute, severe exposure to gram-negative bacterial lipopolysaccharide (LPS) is associated with increased fetal heart rate variability (FHRV). It is unknown whether FHRV is affected by subclinical infection with or without acute exacerbations. We therefore tested the hypothesis that FHRV would be associated with hypotension after acute on chronic exposure to LPS. Chronically instrumented fetal sheep at 0.7 gestation were exposed to a continuous low-dose LPS infusion (n = 12, 100 ng/kg over 24 h, followed by 250 ng·kg(-1)·24 h(-1) for a further 96 h) or the same volume of saline (n = 10). Boluses of either 1 μg LPS or saline were given at 48, 72, and 96 h. Low-dose infusion was not associated with hemodynamic or FHRV changes. The first LPS bolus was associated with tachycardia and suppression of nuchal electromyographic activity in all fetuses. Seven of twelve fetuses developed hypotension (a fall in mean arterial blood pressure ≥5 mmHg). FHRV was transiently increased only at the onset of hypotension, in association with increased cytokine induction and electroencephalogram suppression. FHRV then fell before the nadir of hypotension, with transient suppression of short-term FHRV. After the second LPS bolus, the hypotension group showed a biphasic pattern of a transient increase in FHRV followed by more prolonged suppression. These findings suggest that infection-related hypotension in the preterm fetus mediates the transient increase in FHRV and that repeated exposure to LPS leads to progressive loss of FHRV.
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Affiliation(s)
| | | | | | | | | | | | - Mhoyra Fraser
- Department of Physiology, and The Liggins Institute, University of Auckland, Auckland, New Zealand
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20
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Picchioni D, Reith RM, Nadel JL, Smith CB. Sleep, plasticity and the pathophysiology of neurodevelopmental disorders: the potential roles of protein synthesis and other cellular processes. Brain Sci 2014; 4:150-201. [PMID: 24839550 PMCID: PMC4020186 DOI: 10.3390/brainsci4010150] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 02/26/2014] [Accepted: 03/07/2014] [Indexed: 12/28/2022] Open
Abstract
Sleep is important for neural plasticity, and plasticity underlies sleep-dependent memory consolidation. It is widely appreciated that protein synthesis plays an essential role in neural plasticity. Studies of sleep-dependent memory and sleep-dependent plasticity have begun to examine alterations in these functions in populations with neurological and psychiatric disorders. Such an approach acknowledges that disordered sleep may have functional consequences during wakefulness. Although neurodevelopmental disorders are not considered to be sleep disorders per se, recent data has revealed that sleep abnormalities are among the most prevalent and common symptoms and may contribute to the progression of these disorders. The main goal of this review is to highlight the role of disordered sleep in the pathology of neurodevelopmental disorders and to examine some potential mechanisms by which sleep-dependent plasticity may be altered. We will also briefly attempt to extend the same logic to the other end of the developmental spectrum and describe a potential role of disordered sleep in the pathology of neurodegenerative diseases. We conclude by discussing ongoing studies that might provide a more integrative approach to the study of sleep, plasticity, and neurodevelopmental disorders.
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Affiliation(s)
- Dante Picchioni
- Behavioral Biology Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA; E-Mail:
- Advanced MRI Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
- Section on Neuroadaptation and Protein Metabolism, National Institute of Mental Health, Bethesda, MD 20892, USA; E-Mails: (R.M.R.); (J.L.N.)
| | - R. Michelle Reith
- Section on Neuroadaptation and Protein Metabolism, National Institute of Mental Health, Bethesda, MD 20892, USA; E-Mails: (R.M.R.); (J.L.N.)
| | - Jeffrey L. Nadel
- Section on Neuroadaptation and Protein Metabolism, National Institute of Mental Health, Bethesda, MD 20892, USA; E-Mails: (R.M.R.); (J.L.N.)
| | - Carolyn B. Smith
- Section on Neuroadaptation and Protein Metabolism, National Institute of Mental Health, Bethesda, MD 20892, USA; E-Mails: (R.M.R.); (J.L.N.)
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Abstract
Children surviving premature birth have a high risk of cognitive and learning disabilities and attention deficit. In turn, adverse outcomes are associated with persistent reductions in cerebral growth on magnetic resonance imaging (MRI). It is striking that modern care has been associated with a dramatic reduction in the risk of cystic white matter damage, but modest improvements in terms of neurodevelopmental impairment. This review will explore the hypothesis that the disability is primarily associated with impaired neural connectivity rather than cell death alone. Very preterm infants exhibit reduced thalamocortical connectivity and cortical neuroplasticity compared with term-born controls. In preterm fetal sheep, moderate cerebral ischemia with no neuronal loss, but significant diffuse failure of maturation of cortical pyramidal neurons, was associated with impaired dendritic growth and synapse formation, consistent with altered connectivity. These changes were associated with delayed decline in cortical fractional anisotropy (FA) on MRI. Supporting these preclinical findings, preterm human survivors showed similar enduring impairment of microstructural development of the cerebral cortex defined by FA, consistent with delayed formation of neuronal processes. These findings offer the promise that better understanding of impairment of neural connectivity may allow us to promote normal development and growth of the cortex after preterm birth.
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Abstract
The purpose of this study was to review potential, physiological, hormonal and neuronal mechanisms that may mediate the sleep changes. This paper investigates the literatures regarding the activity of the hypothalamic-pituitary-adrenal (HPA) axis, one of the main neuroendocrine stress systems during sleep in order to identify relations between stress and sleep disorder and the treatment of stress-induced insomnia. Sleep and wakefulness are regulated by the aminergic, cholinergic brainstem and hypothalamic systems. Activation of the HPA and/or the sympathetic nervous systems results in wakefulness and these hormones including corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), cortisol or corticosterone, noradrenaline, and adrenaline, are associated with attention and arousal. Stress-related insomnia leads to a vicious circle by activating the HPA system. An awareness of the close interaction between sleep and stress systems is emerging and the hypothalamus is now recognized as a key center for sleep regulation, with hypothalamic neurontransmitter systems providing the framework for therapeutic advances. An updated understanding of these systems may allow researchers to elucidate neural mechanisms of sleep disorder and to develop effective intervention for sleep disorder.
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Affiliation(s)
- Kuem Sun Han
- College of Nursing, Korea University, Seoul 136-705, Korea
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23
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Varshavsky A. Augmented generation of protein fragments during wakefulness as the molecular cause of sleep: a hypothesis. Protein Sci 2012; 21:1634-61. [PMID: 22930402 PMCID: PMC3527701 DOI: 10.1002/pro.2148] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 08/21/2012] [Indexed: 02/05/2023]
Abstract
Despite extensive understanding of sleep regulation, the molecular-level cause and function of sleep are unknown. I suggest that they originate in individual neurons and stem from increased production of protein fragments during wakefulness. These fragments are transient parts of protein complexes in which the fragments were generated. Neuronal Ca²⁺ fluxes are higher during wakefulness than during sleep. Subunits of transmembrane channels and other proteins are cleaved by Ca²⁺-activated calpains and by other nonprocessive proteases, including caspases and secretases. In the proposed concept, termed the fragment generation (FG) hypothesis, sleep is a state during which the production of fragments is decreased (owing to lower Ca²⁺ transients) while fragment-destroying pathways are upregulated. These changes facilitate the elimination of fragments and the remodeling of protein complexes in which the fragments resided. The FG hypothesis posits that a proteolytic cleavage, which produces two fragments, can have both deleterious effects and fitness-increasing functions. This (previously not considered) dichotomy can explain both the conservation of cleavage sites in proteins and the evolutionary persistence of sleep, because sleep would counteract deleterious aspects of protein fragments. The FG hypothesis leads to new explanations of sleep phenomena, including a longer sleep after sleep deprivation. Studies in the 1970s showed that ethanol-induced sleep in mice can be strikingly prolonged by intracerebroventricular injections of either Ca²⁺ alone or Ca²⁺ and its ionophore (Erickson et al., Science 1978;199:1219-1221; Harris, Pharmacol Biochem Behav 1979;10:527-534; Erickson et al., Pharmacol Biochem Behav 1980;12:651-656). These results, which were never interpreted in connection to protein fragments or the function of sleep, may be accounted for by the FG hypothesis about molecular causation of sleep.
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Affiliation(s)
- Alexander Varshavsky
- Division of Biology, California Institute of Technology, Pasadena, California 91125, USA.
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Affiliation(s)
- Christopher J. Davis
- Sleep and Performance Research Center, WWAMI Medical Education and Program in Neuroscience, Washington State University, 412 E Spokane Falls Boulevard, Spokane, WA 99210-1495, USA
| | - James M. Krueger
- Sleep and Performance Research Center, WWAMI Medical Education and Program in Neuroscience, Washington State University, 412 E Spokane Falls Boulevard, Spokane, WA 99210-1495, USA
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25
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Keogh MJ, Bennet L, Drury PP, Booth LC, Mathai S, Naylor AS, Fraser M, Gunn AJ. Subclinical exposure to low-dose endotoxin impairs EEG maturation in preterm fetal sheep. Am J Physiol Regul Integr Comp Physiol 2012; 303:R270-8. [PMID: 22696578 DOI: 10.1152/ajpregu.00216.2012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Exposure to chorioamnionitis is strongly associated with neurodevelopmental disability after premature birth; however, it remains unclear whether subclinical infection affects functional EEG maturation. Chronically instrumented 103-104-day-old (0.7 gestational age: term 147 days) fetal sheep in utero were randomized to receive either gram-negative LPS by continuous low-dose infusion (100 ng iv over 24 h, followed by 250 ng/24 h for 4 days; n = 6) or the same volume of normal saline (n = 9). Arterial plasma cortisol, ACTH, and IL-6 were measured. The delta (0-3.9 Hz), theta (4-7.9 Hz), alpha (8-12.9 Hz), and beta (13-22 Hz) components of the EEG were determined by power spectral analysis. Brains were taken after 10 days for histopathology. There were no changes in blood gases, cardiovascular variables, or EEG power during LPS infusion, but a transient rise in plasma cortisol and IL-6 (P < 0.05). LPS infusion was associated with loss of the maturational increase to higher frequency activity, with reduced alpha and beta power, and greater delta power than saline controls from 6 to 10 days (P < 0.05). Histologically, LPS was associated with increased numbers of microglia and TNF-α-positive cells in the periventricular white matter and frontoparietal cortex, increased caspase-3-positive cells in white matter, but no loss of CNPase-positive oligodendrocytes, Nurr-1 subplate cells, or gyral complexity. These data suggest that low-dose endotoxin exposure can impair EEG maturation in preterm fetal sheep in association with neural inflammation but without hemodynamic disturbances or cortical injury.
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Affiliation(s)
- Michael J Keogh
- Department of Physiology, University of Auckland, New Zealand
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26
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Zielinski MR, Taishi P, Clinton JM, Krueger JM. 5'-Ectonucleotidase-knockout mice lack non-REM sleep responses to sleep deprivation. Eur J Neurosci 2012; 35:1789-98. [PMID: 22540145 DOI: 10.1111/j.1460-9568.2012.08112.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Adenosine and extracellular adenosine triphosphate (ATP) have multiple physiological central nervous system actions including regulation of cerebral blood flow, inflammation and sleep. However, their exact sleep regulatory mechanisms remain unknown. Extracellular ATP and adenosine diphosphate are converted to adenosine monophosphate (AMP) by the enzyme ectonucleoside triphosphate diphosphohydrolase 1, also known as CD39, and extracellular AMP is in turn converted to adenosine by the 5'-ectonuleotidase enzyme CD73. We investigated the role of CD73 in sleep regulation. Duration of spontaneous non-rapid eye movement sleep (NREMS) was greater in CD73-knockout (KO) mice than in C57BL/6 controls whether determined in our laboratory or by others. After sleep deprivation (SD), NREMS was enhanced in controls but not CD73-KO mice. Interleukin-1 beta (IL1β) enhanced NREMS in both strains, indicating that the CD73-KO mice were capable of sleep responses. Electroencephalographic power spectra during NREMS in the 1.0-2.5 Hz frequency range was significantly enhanced after SD in both CD73-KO and WT mice; the increases were significantly greater in the WT mice than in the CD73-KO mice. Rapid eye movement sleep did not differ between strains in any of the experimental conditions. With the exception of CD73 mRNA, the effects of SD on various adenosine-related mRNAs were small and similar in the two strains. These data suggest that sleep is regulated, in part, by extracellular adenosine derived from the actions of CD73.
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Affiliation(s)
- Mark R Zielinski
- Sleep and Performance Research Center, Programs in Neuroscience, WWAMI Medical Education Program, Washington State University, Spokane, WA 99210-1495, USA
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Schmidt MA, Wisor JP. Interleukin 1 receptor contributes to methamphetamine- and sleep deprivation-induced hypersomnolence. Neurosci Lett 2012; 513:209-13. [PMID: 22387068 DOI: 10.1016/j.neulet.2012.02.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 01/20/2012] [Accepted: 02/13/2012] [Indexed: 10/28/2022]
Abstract
Methamphetamine-induced wakefulness is dependent on monoamine transporter blockade. Subsequent to methamphetamine-induced wakefulness, the amount of time spent asleep and the depth of sleep are increased relative to baseline sleep. The mechanisms that drive methamphetamine-induced hypersomnolence are not fully understood. We recently observed that methamphetamine exposure elevates the expression of the sleep-promoting cytokine, interleukin-1β in CD11b-positive monocytes within the brain. Here, we sought to determine whether activation of the interleukin 1 receptor (IL1R) drives the increase in the depth and amount of sleep that occurs subsequent to methamphetamine-induced wakefulness. IL1R-deficient mice and wild type control mice were subjected to systemic methamphetamine (1 and 2mg/kg) and saline treatments. The wake-promoting effect of methamphetamine was modestly potentiated by IL1R-deficiency. Additionally, the increase in time spent in NREMS subsequent to methamphetamine-induced wakefulness in wild type mice was abolished in IL1R-deficient mice. The increase in time spent asleep after 3h of behaviorally enforced wakefulness was also abolished in IL1R-deficient mice. Increases in EEG slow wave activity triggered by methamphetamine and sleep deprivation were of equal magnitude in IL1R-deficient and wild type mice. These data demonstrate that IL1R activation contributes to hypersomnolence that occurs after sleep loss, whether that sleep loss is triggered pharmacologically by methamphetamine or through behavioral sleep deprivation.
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Affiliation(s)
- Michelle A Schmidt
- WWAMI Medical Education Program and Department of Veterinary Comparative Anatomy, Pharmacology and Physiology, Washington State University, Spokane, WA 99202, United States
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Claycomb RJ, Hewett SJ, Hewett JA. Neuromodulatory role of endogenous interleukin-1β in acute seizures: possible contribution of cyclooxygenase-2. Neurobiol Dis 2011; 45:234-42. [PMID: 21856425 DOI: 10.1016/j.nbd.2011.08.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 07/20/2011] [Accepted: 08/03/2011] [Indexed: 10/17/2022] Open
Abstract
The function of endogenous interleukin-1β (IL-1β) signaling in acute seizure activity was examined using transgenic mice harboring targeted deletions in the genes for either IL-1β (Il1b) or its signaling receptor (Il1r1). Acute epileptic seizure activity was modeled using two mechanistically distinct chemoconvulsants, kainic acid (KA) and pentylenetetrazole (PTZ). KA-induced seizure activity was more severe in homozygous null (-/-) Il1b mice compared to their wild-type (+/+) littermate controls, as indicated by an increase in the incidence of sustained generalized convulsive seizure activity. In the PTZ seizure model, the incidence of acute convulsive seizures was increased in both Il1b and Il1r1-/- mice compared to their respective +/+ littermate controls. Interestingly, the selective cyclooxygenase (COX)-2 inhibitor, rofecoxib, mimicked the effect of IL-1β deficiency on PTZ-induced convulsions in Il1r1+/+ but not -/- mice. Together, these results suggest that endogenous IL-1β possesses anticonvulsive properties that may be mediated by arachidonic acid metabolites derived from the catalytic action of COX-2.
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Affiliation(s)
- Robert J Claycomb
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT 06030, USA
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Chou IC, Lin WD, Wang CH, Tsai CH, Li TC, Tsai FJ. Interleukin (IL)-1beta, IL-1 receptor antagonist, IL-6, IL-8, IL-10, and tumor necrosis factor alpha gene polymorphisms in patients with febrile seizures. J Clin Lab Anal 2011; 24:154-9. [PMID: 20486195 DOI: 10.1002/jcla.20374] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Inflammation and genetics may play a role in the pathogenesis of febrile seizures (FSs). We aimed to test whether interleukin-1beta (IL-1beta), IL-1 receptor antagonist (IL-1 Ra), IL-6 promoter, IL-8, IL-10, or tumor necrosis factor (TNF) gene polymorphisms could be used as markers of susceptibility to FSs. An association study was performed among a cohort of 104 patients with FSs and 143 normal control subjects. There was no significant difference between patients and controls in the distribution of allele frequencies of the IL-1beta promoter, IL-1beta exon 5, IL-6 promoter, IL-8, IL-10, or TNF-alpha gene polymorphisms. In contrast, the IL-1 Ra-I homozygote was more frequent in patients with FSs than in healthy controls (93.2% vs. 83.92%, chi(2)=4.51, P=0.034). In addition, individuals homozygous for the IL-1 Ra-I genotype were more than twice as likely to develop FSs than individuals heterozygous for the IL-1 Ra-I/II genotype (OR, 2.63, 95% CI: 1.08-6.39; chi(2)=4.55, P=0.033). We conclude that the IL-1 Ra gene might be one of the useful markers for predicting susceptibility to FSs.
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Affiliation(s)
- I-Ching Chou
- Children's Medical Center, China Medical University Hospital, Taichung, Taiwan
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Abstract
PURPOSE The symptom most frequently associated with sickle cell disease (SCD) is pain, but recent research is beginning to indicate that fatigue as an increasingly important symptom of this disease upon which to focus research efforts. This article explores biological and behavioral factors that can potentially contribute to fatigue in SCD. ORGANIZING FRAMEWORK A biobehavioral framework guides this discussion of factors that may contribute to SCD fatigue. FINDINGS The pathophysiology of the disease process, such as the profound hemolytic anemia and unpredictable vasoocclusive crises, suggests that individuals with SCD are at risk for both acute and chronic fatigue. For example, hypoxemia can cause muscle weakness and produce oxidative stress, which, in turn, increases fatigue. Sickled erythrocytes disrupt the vascular endothelium and stimulate proinflammatory cytokines, which are linked to sleep disruptions. Pain, the most notorious symptom of SCD, has a complex and mechanistically poorly understood relationship with fatigue. CONCLUSIONS Little is known about the symptom of fatigue in SCD. Considering the biological and behavioral factors of SCD that could potentially contribute to fatigue, there is a great need for research on the nature and potential mechanisms of fatigue in SCD. CLINICAL RELEVANCE Fatigue in SCD may negatively affect quality of life. Understanding factors that may contribute to fatigue aids the clinician in identifying causes and determining treatment.
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Affiliation(s)
- Suzanne Ameringer
- Virginia Commonwealth University, School of Nursing, Richmond, VA, USA
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Brambilla D, Barajon I, Bianchi S, Opp MR, Imeri L. Interleukin-1 inhibits putative cholinergic neurons in vitro and REM sleep when microinjected into the rat laterodorsal tegmental nucleus. Sleep 2010; 33:919-29. [PMID: 20614852 DOI: 10.1093/sleep/33.7.919] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
STUDY OBJECTIVES REM sleep is suppressed during infection, an effect mimicked by the administration of cytokines such as interleukin-1 (IL-1). In spite of this observation, brain sites and neurochemical systems mediating IL-1-induced suppression of REM sleep have not been identified. Cholinergic neurons in the brainstem laterodorsal tegmental nucleus (LDT) are part of the neuronal circuitry responsible for REM sleep generation. Since IL-1 inhibits acetylcholine synthesis and release, the aim of this study was to test the two different, but related hypotheses. We hypothesized that IL-1 inhibits LDT cholinergic neurons, and that, as a result of this inhibition, IL-1 suppresses REM sleep. DESIGN, MEASUREMENT, AND RESULTS To test these hypotheses, the electrophysiological activity of putative cholinergic LDT neurons was recorded in a rat brainstem slice preparation. Interleukin-1 significantly inhibited the firing rate of 76% of recorded putative cholinergic LDT neurons and reduced the amplitude of glutamatergic evoked potentials in 60% of recorded neurons. When IL-1 (1 ng) was microinjected into the LDT of freely behaving rats, REM sleep was reduced by about 50% (from 12.7% +/- 1.5% of recording time [after vehicle] to 6.1% +/- 1.4% following IL-1 administration) during post-injection hours 3-4. CONCLUSIONS Results of this study support the hypothesis that IL-1 can suppress REM sleep by acting at the level of the LDT nucleus. Furthermore this effect may result from the inhibition of evoked glutamatergic responses and of spontaneous firing of putative cholinergic LDT neurons.
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Affiliation(s)
- Dario Brambilla
- Department of Human Physiology, University of Milan Medical School, Milan, Italy
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32
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Kim L. Stress, Sleep Physiology, and Related Insomnia Disorders. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2010. [DOI: 10.5124/jkma.2010.53.8.707] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Leen Kim
- Department of Psychiatry, College of Medicine, Korea University, Seoul, Korea
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Abstract
This article reviews the epidemiology of autoimmune conditions in schizophrenia, symptom manifestations of autoimmune conditions resembling schizophrenia, and the immunological changes observed in schizophrenia; and reflects on their associations with neurodevelopment, neurodegeneration, clinical course, and management of schizophrenia.
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Abstract
The brain uses a variety of mechanisms to survey the immune system constantly. Responses of the immune system to invading pathogens are detected by the central nervous system, which responds by orchestrating complex changes in behavior and physiology. Sleep is one of the behaviors altered in response to immune challenge. The role of cytokines as mediators of responses to infectious challenge and regulators and modulators of sleep is the focus of this article.
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Affiliation(s)
- Mark R Opp
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI 48109-0615, USA.
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Abstract
Good sleep is necessary for physical and mental health. For example, sleep loss impairs immune function, and sleep is altered during infection. Immune signalling molecules are present in the healthy brain, where they interact with neurochemical systems to contribute to the regulation of normal sleep. Animal studies have shown that interactions between immune signalling molecules (such as the cytokine interleukin 1) and brain neurochemical systems (such as the serotonin system) are amplified during infection, indicating that these interactions might underlie the changes in sleep that occur during infection. Why should the immune system cause us to sleep differently when we are sick? We propose that the alterations in sleep architecture during infection are exquisitely tailored to support the generation of fever, which in turn imparts survival value.
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Cytokines in Synaptic Function. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s1567-7443(07)10007-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Brambilla D, Franciosi S, Opp MR, Imeri L. Interleukin-1 inhibits firing of serotonergic neurons in the dorsal raphe nucleus and enhances GABAergic inhibitory post-synaptic potentials. Eur J Neurosci 2007; 26:1862-9. [PMID: 17868373 DOI: 10.1111/j.1460-9568.2007.05796.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In vitro electrophysiological data suggest that interleukin-1 may promote non-rapid eye movement sleep by inhibiting spontaneous firing of wake-active serotonergic neurons in the dorsal raphe nucleus (DRN). Interleukin-1 enhances GABA inhibitory effects. DRN neurons are under an inhibitory GABAergic control. This study aimed to test the hypothesis that interleukin-1 inhibits DRN serotonergic neurons by potentiating GABAergic inhibitory effects. In vitro intracellular recordings were performed to assess the responses of physiologically and pharmacologically identified DRN serotonergic neurons to rat recombinant interleukin-1beta. Coronal slices containing DRN were obtained from male Sprague-Dawley rats. The impact of interleukin-1 on firing rate and on evoked post-synaptic potentials was determined. Evoked post-synaptic potentials were induced by stimulation with a bipolar electrode placed on the surface of the slice ventrolateral to DRN. Addition of interleukin-1 (25 ng/mL) to the bath perfusate significantly decreased firing rates of DRN serotonergic neurons from 1.3 +/- 0.2 Hz (before administration) to 0.7 +/- 0.2 Hz. Electrical stimulation induced depolarizing evoked post-synaptic potentials in DRN serotonergic neurons. The application of glutamatergic and GABAergic antagonists unmasked two different post-synaptic potential components: a GABAergic evoked inhibitory post-synaptic potentials and a glutamatergic evoked excitatory post-synaptic potentials, respectively. Interleukin-1 increased GABAergic evoked inhibitory post-synaptic potentials amplitudes by 30.3 +/- 3.8% (n = 6) without affecting glutamatergic evoked excitatory post-synaptic potentials. These results support the hypothesis that interleukin-1 inhibitory effects on DRN serotonergic neurons are mediated by an interleukin-1-induced potentiation of evoked GABAergic inhibitory responses.
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Affiliation(s)
- D Brambilla
- Institute of Human Physiology II, Guiseppe Moruzzi Center for Experimental Sleep Research, University of Milan Medical School, Via Mangiagalli, 32, 20133 Milano, Italy.
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38
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Affiliation(s)
- James M Krueger
- Program in Neuroscience, Washington State University, Pullman, WA 99164
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39
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Morita M, Saruta C, Kozuka N, Okubo Y, Itakura M, Takahashi M, Kudo Y. Dual regulation of astrocyte gap junction hemichannels by growth factors and a pro-inflammatory cytokine via the mitogen-activated protein kinase cascade. Glia 2007; 55:508-15. [PMID: 17211868 DOI: 10.1002/glia.20471] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Evidence that glutamate and ATP release from astrocytes can occur via gap junction hemichannels (GJHCs) is accumulating. However, the GJHC is still only one possible release mechanism and has not been detected in some studies, although this may be because the levels were below those detectable by the system used. Because of these conflicting results, we hypothesized that release from astrocyte GJHCs might depend on different astrocyte states, and screened for factors affecting astrocyte GJHC activity by measuring fluorescent dye leakage via GJHCs using a conventional method for GJHC acivation, i.e. removal of extracellular divalent cations. Astrocytes cultured in Dulbecco's minimal essential medium containing 10% fetal calf serum, a medium widely used for astrocyte studies, did not show dye leakage, whereas those cultured in a defined medium showed substantial dye leakage, which was confirmed pharmacologically to be due to GJHCs and not to P2x7 receptors. EGF and bFGF inhibited the GJHC activity via the mitogen-activated protein kinase cascade, and the effect of the growth factors was reversed by interleukin-1beta. These factors altered GJHC activity within 10 min, but did not affect connexin 43 expression. GJHC activity in hippocampal slice culture preparations was measured using the same methods and found to be regulated in a similar manner. These results indicate that astrocyte GJHC activity is regulated by brain environmental factors.
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Affiliation(s)
- Mitsuhiro Morita
- Laboratory of Cellular Neurobiology, School of Life Science, Tokyo University of Pharmacy and Life Science, Tokyo, Japan.
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40
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Frosini M. Changes in CSF composition during heat stress and fever in conscious rabbits. PROGRESS IN BRAIN RESEARCH 2007; 162:449-57. [PMID: 17645932 DOI: 10.1016/s0079-6123(06)62022-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Elevation of brain temperature after stroke can lead to severe brain injury and even a moderate hyperthermia correlates with increased nervous damage. The role of endogenous cryogens in the pathways that down-regulate body temperature are of overwhelming interest in view of their effectiveness in protecting brain from such damage. The aim of the present work was to study whether heat stress (HS) or fever generates brain homeostatic responses aimed at counteracting the resulting rise in body temperature. Conscious rabbits, with cannulas chronically implanted in the cisterna magna and lateral ventricle, underwent HS (50 min, 40 degrees C) or were injected with 25 ng of endogenous pyrogen IL-1beta, while cerebrospinal fluid (CSF) levels of amino acids involved in central mechanisms of thermoregulation like taurine, GABA, aspartate and glutamate were monitored. The concentrations of some CSF cations (Na(+), K(+), Mg(2+) and Ca(2+)) were also determined in view of their purported role (sodium and calcium in particular) in establishing the thermal set point within the hypothalamus. Results show that during HS-induced hyperthermia, CSF taurine and GABA levels were significantly increased. On the contrary, IL-1beta caused an increase in CSF taurine and, concurrently, a decrease in CSF GABA. Aspartate and glutamate did not change in both conditions. Furthermore, among CSF cations, only calcium and sodium underwent changes. In particular, calcium content increased both in HS- and febrile-animals, while CSF sodium decreased significantly only under IL-1beta-injected treatment. In conclusion, GABA and taurine contribute as endogenous cryogens in a different fashion to the central mechanisms, which regulate dissipation of body heat in hyperthermia or heat production in fever, possibly in coordination with extracellular calcium and sodium.
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Affiliation(s)
- Maria Frosini
- Dipartimento di Scienze Biomediche, Sezione di Farmacologia, Fisiologia e Tossicologia Università di Siena, Polo Scientifico di S. Miniato viale A. Moro 2, lotto C 53100 Siena, Italy.
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Stone EA, Lehmann ML, Lin Y, Quartermain D. Depressive behavior in mice due to immune stimulation is accompanied by reduced neural activity in brain regions involved in positively motivated behavior. Biol Psychiatry 2006; 60:803-11. [PMID: 16814258 DOI: 10.1016/j.biopsych.2006.04.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2006] [Revised: 04/25/2006] [Accepted: 04/25/2006] [Indexed: 12/27/2022]
Abstract
BACKGROUND Immune stimulation inhibits positively motivated behavior and induces depressive illness. To help clarify the mechanism of these effects, neural activity in response to a positive stimulus was examined in brain regions associated with positively motivated activity defined on the basis of prior behavioral studies of central alpha1-adrenoceptor action. METHODS Mice pretreated with either lipopolysaccharide or, for comparison, reserpine were exposed to a motivating stimulus (fresh cage) and subsequently assayed for fos expression and mitogen-activated protein kinase (MAPK) phosphorylation, two measures associated with alpha1-adrenoceptor-dependent neural activity, in several positive-activity-related (motor, piriform, cingulate cortex, nucleus accumbens, locus coeruleus) and stress-related brain regions (paraventricular hypothalamus, bed nucleus stria terminalis). RESULTS Both lipopolysaccharide and reserpine pretreatment abolished fresh cage-induced fos expression and MAPK activation in the positive activity-related brain regions but enhanced these measures in the stress-related areas. CONCLUSIONS The results support the hypothesis that immune activation reduces alpha1-adrenoceptor-related signaling and neural activity in brain regions associated with positive activity while it increases these functions in stress-associated areas. It is suggested that neural activities of these two types of brain regions are mutually antagonistic and that a reciprocal shift toward the stress regions is a factor in the loss of positively motivated behaviors in sickness behavior and depressive illness.
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Affiliation(s)
- Eric A Stone
- Department of Psychiatry, New York University School of Medicine, New York, New York 10016, USA.
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Stone EA, Quartermain D, Lin Y, Lehmann ML. Central alpha1-adrenergic system in behavioral activity and depression. Biochem Pharmacol 2006; 73:1063-75. [PMID: 17097068 DOI: 10.1016/j.bcp.2006.10.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 09/27/2006] [Accepted: 10/02/2006] [Indexed: 02/06/2023]
Abstract
Central alpha(1)-adrenoceptors are activated by norepinephrine (NE), epinephrine (EPI) and possibly dopamine (DA), and function in two fundamental and opposed types of behavior: (1) positively motivated exploratory and approach activities, and (2) stress reactions and behavioral inhibition. Brain microinjection studies have revealed that the positive-linked receptors are located in eight to nine brain regions spanning the neuraxis including the secondary motor cortex, piriform cortex, nucleus accumbens, preoptic area, lateral hypothalamic area, vermis cerebellum, locus coeruleus, dorsal raphe and possibly the C1 nucleus of the ventrolateral medulla, whereas the stress-linked receptors are present in at least three areas including the paraventricular nucleus of the hypothalamus, central nucleus of the amygdala and bed nucleus of the stria terminalis. Recent studies utilizing c-fos expression and mitogen-activated protein kinase activation have shown that various diverse models of depression in mice produce decreases in positive region-neural activity elicited by motivating stimuli along with increases in neural activity of stress areas. Both types of change are attenuated by various antidepressant agents. This has suggested that the balance of the two networks determines whether an animal displays depressive behavior. A central unresolved question concerns how the alpha(1)-receptors in the positive-activity and stress systems are differentially activated during the appropriate behavioral conditions and to what extent this is related to differences in endogenous ligands or receptor subtype distributions.
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Affiliation(s)
- Eric A Stone
- New York University School of Medicine, Department of Psychiatry, NYU Medical Center, MHL HN510, 550 First Avenue, New York, NY 10016, USA.
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43
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Abstract
Personal experience indicates we sleep differently when sick. Data reviewed demonstrate the extent to which sleep is altered during the course of infection of host organisms by several classes of pathogens. One important unanswered question is whether or not the alterations in sleep during infection are of functional relevance. That is, does the way we sleep when sick facilitate or impede recovery? One retrospective, preclinical study suggests that sleep changes during infection are of functional relevance. Toth and colleagues [102] analyzed sleep responses of rabbits to three different microbial infections. Those rabbits that exhibited robust increases in NREM sleep were more likely to survive than those that exhibited long periods of NREM sleep suppression. These tantalizing data suggest that the precise alterations in sleep through the course of infection are important determinants of morbidity and mortality. Data from healthy subjects demonstrate a role for at least two cytokines in the regulation of spontaneous, physiologic NREM sleep. A second critical yet unanswered question is whether or not cytokines mediate infection-induced alterations in sleep. The hypothesis that cytokines mediate infection-induced alterations in sleep is logical based on observations of the impact of infection on levels of cytokines in the peripheral immune system and in the brain. No attempts have been made to intervene with cytokine systems in brain during the course of infection to determine if there is an impact on infection-induced alterations in sleep. Although substantial progress has been made in elucidating the myriad mechanisms by which cytokines regulate and modulate sleep, much remains to be determined with respect to mechanistic and functional aspects of infection-induced alterations in sleep.
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Affiliation(s)
- Mark R Opp
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI 48109-0615, USA.
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44
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Serantes R, Arnalich F, Figueroa M, Salinas M, Andrés-Mateos E, Codoceo R, Renart J, Matute C, Cavada C, Cuadrado A, Montiel C. Interleukin-1beta enhances GABAA receptor cell-surface expression by a phosphatidylinositol 3-kinase/Akt pathway: relevance to sepsis-associated encephalopathy. J Biol Chem 2006; 281:14632-43. [PMID: 16567807 DOI: 10.1074/jbc.m512489200] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Sepsis-associated encephalopathy (SAE) is a frequent but poorly understood neurological complication in sepsis that negatively influences survival. Here we present clinical and experimental evidence that this brain dysfunction may be related to altered neurotransmission produced by inflammatory mediators. Compared with septic patients, SAE patients had higher interleukin-1beta (IL-1beta) plasma levels; interestingly, these levels decreased once the encephalopathy was resolved. A putative IL-1beta effect on type A gamma-aminobutyric acid receptors (GABA(A)Rs), which mediate fast synaptic transmission in most cerebral inhibitory synapses in mammals, was investigated in cultured hippocampal neurons and in Xenopus oocytes expressing native or foreign rat brain GABA(A)Rs, respectively. Confocal images in both cell types revealed that IL-1beta increases recruitment of GABA(A)Rs to the cell surface. Moreover, brief applications of IL-1beta to voltage-clamped oocytes yielded a delayed potentiation of the GABA-elicited chloride currents (I(GABA)); this effect was suppressed by IL-1ra, the natural IL-1 receptor (IL-1RI) antagonist. Western blot analysis combined with I(GABA) recording and confocal images of GABA(A) Rs in oocytes showed that IL-1beta stimulates the IL-1RI-dependent phosphatidylinositol 3-kinase activation and the consequent facilitation of phospho-Akt-mediated insertion of GABA(A)Rs into the cell surface. The interruption of this signaling pathway by specific phosphatidylinositol 3-kinase or Akt inhibitors suppresses the cytokine-mediated effects on GABA(A)R, whereas activation of the conditionally active form of Akt1 (myr-Akt1.ER*) with 4-hydroxytamoxifen reproduces the effects. These findings point to a previously unrecognized signaling pathway that connects IL-1beta with increased "GABAergic tone." We propose that through this mechanism IL-1beta might alter synaptic strength at central GABAergic synapses and so contribute to the cognitive dysfunction observed in SAE.
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Affiliation(s)
- Rocío Serantes
- Departamento de Medicina, Hospital Universitario La Paz, Paseo de la Castellana 261, 28046 Madrid, Spain
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Zhu G, Okada M, Yoshida S, Mori F, Hirose S, Wakabayashi K, Kaneko S. Involvement of Ca(2+)-induced Ca2+ releasing system in interleukin-1beta-associated adenosine release. Eur J Pharmacol 2006; 532:246-52. [PMID: 16487508 DOI: 10.1016/j.ejphar.2005.12.085] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Revised: 11/24/2005] [Accepted: 12/19/2005] [Indexed: 11/16/2022]
Abstract
Interleukin-1beta (IL-1beta) plays an important role in neuroprotective and neurodegenerative events in the central nervous system. To clarify the mechanism of controversial actions of IL-1beta, we determined the effect of IL-1beta, as well as the interaction between IL-1beta and Ca(2+)-induced Ca2+ releasing system (CICR), on adenosine releases in mice hippocampus using mini-slices method. Basal and K(+)-stimulated adenosine releases were regulated by two types of CICRs, including inositol-1,4,5-trisphosphate (IP3) receptor and ryanodine receptor. Lower concentration of IL-1beta increased both adenosine releases, whereas higher concentration did not affect their releases. The stimulatory effect of IL-1beta on basal adenosine release was reduced by removal of extracellular Ca2+ and IP3 receptor inhibitor, while the stimulatory effect of IL-1beta on K(+)-stimulated adenosine release was reduced by ryanodine receptor inhibitor. These results suggest that the potent effect of IL-1beta upon adenosine release might contribute to the neuroprotective action of IL-1beta, whereas IL-1beta-induced neurodegeneration might be due to the overload response of Ca2+ mobilization and the inactivation of adenosine exocytosis.
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Affiliation(s)
- Gang Zhu
- Department of Neuropsychiatry, Hirosaki University School of Medicine, Hirosaki 036-8562, Japan
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46
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Xiong Y, Donovan KA, Kline MP, Gornet MK, Moon-Tasson LL, Lacy MQ, Dispenzieri A, Gertz MA, Greipp PR, Lust JA. Identification of Two Groups of Smoldering Multiple Myeloma Patients Who Are Either High or Low Producers of Interleukin-1. J Interferon Cytokine Res 2006; 26:83-95. [PMID: 16487028 DOI: 10.1089/jir.2006.26.83] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Interleukin-1beta (IL-1beta) is abnormally expressed by the plasma cells obtained from myeloma patients, and it is a potent inducer of the important myeloma growth factor, IL-6. We investigated whether levels of IL-1beta biologic activity might distinguish different groups of patients with smoldering multiple myeloma (SMM). We measured the ability of IL-6 production by bone marrow stromal cells to serve as a surrogate marker for IL-1beta biologic activity. Using this IL-1beta bioassay, we found that it is sensitive at < 1 pg/ml of recombinant IL-1beta and that IL-1beta biologic activity is detectable with either mature or pro-IL-1beta-transduced myeloma cell lines. Patients with active myeloma induced quantitatively higher levels of stromal cell IL-6 production when compared with those with monoclonal gammopathy of undetermined significance (MGUS). The bioassay distinguished two groups of SMM patients, those who were high producers, similar to patients with active MM, and those who were low producers, comparable to MGUS patients. IL-1 antagonists inhibited the paracrine IL-6 production by > or = 90% in the majority of patients with an elevated IL-6 level. Based on such studies, it may be possible to predict patients that will progress to active MM and to delay or prevent this progression with IL-1 antagonists.
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Affiliation(s)
- Yuning Xiong
- Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
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47
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Abstract
Personal experience and empirical data indicate sleep is altered during sickness. Important signaling molecules of the peripheral immune system called cytokines orchestrate responses to infection. Through a variety of mechanisms, the brain detects activation of the peripheral immune system. The brain responds to infection by altering physiological processes and complex behavior, including sleep. These changes in physiology and behavior collectively function to support the immune system, and under normal circumstances the health of the host is restored. Several of these cytokines, and their receptors, are present in normal healthy brain. Some cytokines regulate sleep under physiological conditions, in the absence of infection or immune challenge. For example, interleukin-1 directly alters discharge patterns of neurons in hypothalamic and brainstem circuits implicated in the regulation of sleep-wake behavior. Many other cytokines modulate sleep because they interact with neurotransmitter, peptide, and/or hormone systems to initiate a cascade of responses that subsequently alter sleep-wake behavior. Because cytokines regulate/modulate sleep-wake behavior in the absence of immune challenge, and cytokine concentrations and profiles are altered during infection, it is likely that cytokines mediate infection-induced alterations in sleep. Whether the changes in sleep that occur during infection are beneficial and aid in recovery remains to be determined.
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Affiliation(s)
- Mark R Opp
- Department of Anesthesiology, University of Michigan, 7422 Medical Sciences Bldg. I, 1150 W. Medical Center Drive, Ann Arbor, MI 48109-0615, USA.
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48
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Hellstrom IC, Danik M, Luheshi GN, Williams S. Chronic LPS exposure produces changes in intrinsic membrane properties and a sustained IL-beta-dependent increase in GABAergic inhibition in hippocampal CA1 pyramidal neurons. Hippocampus 2005; 15:656-64. [PMID: 15889405 DOI: 10.1002/hipo.20086] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Chronic inflammation has been reported to be a significant factor in the induction and progression of a number of chronic neurological disorders including Alzheimer's disease and Down syndrome. It is believed that inflammation may promote synaptic dysfunction, an effect that is mediated in part by pro-inflammatory cytokines such as interleukin-1beta (IL-1beta). However, the role of IL-1beta and other cytokines in synaptic transmission is still poorly understood. In this study, we have investigated how synaptic transmission and neuronal excitability in hippocampal pyramidal neurons are affected by chronic inflammation induced by exposing organotypic slices to the bacterial cell-wall product lipopolysaccharide (LPS). We report that CA1 pyramidal neurons recorded in whole cell from slices previously exposed to LPS for 7 days had resting membrane potential and action potential properties similar to those of the controls. However, they had significantly lower membrane resistance and a more elevated action potential threshold, and displayed a slower frequency of action potential discharge. Moreover, the amplitude of pharmacologically isolated postsynaptic gamma-aminobutyric acid (GABA)ergic potentials, but not excitatory glutamatergic postsynaptic potentials, was significantly larger following chronic LPS exposure. Interestingly, co-incubation of the IL-1 receptor antagonist (IL-1Ra) concurrently with LPS prevented the increase in GABAergic transmission, but not the reduction in intrinsic neuronal excitability. Finally, we confirmed that LPS dramatically increased IL-1beta, and IL-1beta-dependent IL-6 levels in the culture medium for 2 days before returning to baseline. We conclude that CA1 pyramidal neurons in slices chronically exposed to LPS show a persistent decrease in excitability due to a combined decrease in intrinsic membrane excitability and an enhancement in synaptic GABAergic input, the latter being dependent on IL-1beta. Therefore, chronic inflammation in hippocampus produces IL-1beta-dependent and -independent effects in neuronal and synaptic function that could contribute significantly to cognitive disturbances.
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Affiliation(s)
- Ian C Hellstrom
- Douglas Hospital Research Centre, McGill University, Montréal, Québec, Canada
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Tang C, Sula MJ, Bohnet S, Rehman A, Taishi P, Krueger JM. Interleukin-1beta induces CREB-binding protein (CBP) mRNA in brain and the sequencing of rat CBP. ACTA ACUST UNITED AC 2005; 137:213-22. [PMID: 15950780 DOI: 10.1016/j.molbrainres.2005.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2004] [Revised: 03/08/2005] [Accepted: 03/13/2005] [Indexed: 10/25/2022]
Abstract
Interleukin-1 beta (IL-1) and CREB have many CNS actions including sleep regulation and hippocampal-dependent learning. CREB acts in part via CREB-binding protein (CBP). We thus determined whether IL-1 could induce CBP gene expression. Initially, cultured hippocampal cells were treated with IL-1 and differential display reverse transcription was used to identify up- and down-regulated genes. We then sequenced rat CBP. Of the IL-1-upregulated genes, CBP and adenine nucleotide translocator-1 (ANT-1) were investigated in vivo. In these experiments, IL-1 was given to rats intraventricularly and sacrificed 2 h later; both CBP and ANT-1 transcripts were upregulated in the cerebral cortex and hypothalamus. We conclude that rat CBP shares many of the functional domains as human and murine CBP and that IL-1 upregulates genes previously associated with learning and sleep.
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Affiliation(s)
- Chad Tang
- Department of VCAPP, Program in Neuroscience, Washington State University, PO Box 646520, Pullman, WA 99164-6520, USA
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Lee JK, Won JS, Singh AK, Singh I. Adenosine kinase inhibitor attenuates the expression of inducible nitric oxide synthase in glial cells. Neuropharmacology 2005; 48:151-60. [PMID: 15617735 DOI: 10.1016/j.neuropharm.2004.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Revised: 08/11/2004] [Accepted: 09/16/2004] [Indexed: 11/21/2022]
Abstract
The present study demonstrates the anti-inflammatory effect of adenosine kinase inhibitor (ADKI) in glial cells. Treatment of glial cells with IC51, an ADKI, stimulated the extracellular adenosine release and reduced the LPS/IFNgamma-mediated production of NO, and induction of iNOS and TNF-alpha gene expression. The recovery of IC51-mediated inhibition of iNOS expression by adenosine transport inhibitor, S-(4-nitrobenzyl)-6-thioinosine (NBTI), and the inhibition of LPS/IFNgamma-induced iNOS gene expression by exogenous adenosine indicate a role for adenosine release in IC51-mediated iNOS expression. The rescue of IC51-mediated inhibition of iNOS expression by adenosine receptor antagonist for A2A, 8-(3-chlorostyryl)caffeine (CSC) and alloxazine for A2B, further supports a role for interaction of adenosine and its receptors in anti-inflammatory activity. The IC51-mediated induction of cAMP levels, downstream target of A2A and A2B, and inhibition of LPS/IFNgamma-induced expression of iNOS by forskolin, a cAMP activator, document a role for cAMP mediated pathway in anti-inflammatory activity of IC51. Taken together, these studies document that IC51-mediated inhibition of iNOS expression is through activation of adenosine receptors, which activates A2A and A2B resulting in increased cAMP levels following LPS/IFNgamma stimulation. Moreover, the lack of effect of IC51 or adenosine on NFkappaB DNA binding activity and its transactivity indicates that the inhibition of iNOS expression mediated by IC51 may be through an NFkappaB independent pathway.
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Affiliation(s)
- Jin-Koo Lee
- Department of Pediatrics, Medical University of South Carolina, 96 Jonathan Lucas Street, 316 Clinical Science Building, Charleston, SC 29425, USA
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