1
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Liao Y, Wen R, Fu S, Cheng X, Ren S, Lu M, Qian L, Luo F, Wang Y, Xiao Q, Wang X, Ye H, Zhang X, Jiang C, Li X, Li S, Dang R, Liu Y, Kang J, Yao Z, Yan J, Xiong J, Wang Y, Wu S, Chen X, Li Y, Xia J, Hu Z, He C. Spatial memory requires hypocretins to elevate medial entorhinal gamma oscillations. Neuron 2024; 112:155-173.e8. [PMID: 37944520 DOI: 10.1016/j.neuron.2023.10.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 08/07/2023] [Accepted: 10/09/2023] [Indexed: 11/12/2023]
Abstract
The hypocretin (Hcrt) (also known as orexin) neuropeptidic wakefulness-promoting system is implicated in the regulation of spatial memory, but its specific role and mechanisms remain poorly understood. In this study, we revealed the innervation of the medial entorhinal cortex (MEC) by Hcrt neurons in mice. Using the genetically encoded G-protein-coupled receptor activation-based Hcrt sensor, we observed a significant increase in Hcrt levels in the MEC during novel object-place exploration. We identified the function of Hcrt at presynaptic glutamatergic terminals, where it recruits fast-spiking parvalbumin-positive neurons and promotes gamma oscillations. Bidirectional manipulations of Hcrt neurons' projections from the lateral hypothalamus (LHHcrt) to MEC revealed the essential role of this pathway in regulating object-place memory encoding, but not recall, through the modulation of gamma oscillations. Our findings highlight the significance of the LHHcrt-MEC circuitry in supporting spatial memory and reveal a unique neural basis for the hypothalamic regulation of spatial memory.
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Affiliation(s)
- Yixiang Liao
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Ruyi Wen
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Shengwei Fu
- State Key Laboratory of Membrane Biology, School of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, National Biomedical Imaging Center, Peking University, Beijing 100871, China
| | - Xiaofang Cheng
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Shuancheng Ren
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Minmin Lu
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Ling Qian
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Fenlan Luo
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Yaling Wang
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Qin Xiao
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Xiao Wang
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Hengying Ye
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Xiaolong Zhang
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Chenggang Jiang
- Department of Medical Psychology, Chongqing Health Center for Women and Children, Chongqing 400021, China
| | - Xin Li
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Shiyin Li
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Ruozhi Dang
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Yingying Liu
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Junjun Kang
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Zhongxiang Yao
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Jie Yan
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Jiaxiang Xiong
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China
| | - Yanjiang Wang
- Department of Neurology, Daping Hospital, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400042, China; Chongqing Institute for Brain and Intelligence, Guangyang Bay Laboratory, Chongqing 400064, China
| | - Shengxi Wu
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Xiaowei Chen
- Brain Research Center, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China; Chongqing Institute for Brain and Intelligence, Guangyang Bay Laboratory, Chongqing 400064, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, School of Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking-Tsinghua Center for Life Sciences, National Biomedical Imaging Center, Peking University, Beijing 100871, China
| | - Jianxia Xia
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China.
| | - Zhian Hu
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China; Chongqing Institute for Brain and Intelligence, Guangyang Bay Laboratory, Chongqing 400064, China.
| | - Chao He
- Department of Physiology, Institute of Brain and Intelligence, Third Military Medical University, Chongqing 400038, China.
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2
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Datta D, Perone I, Morozov YM, Arellano J, Duque A, Rakic P, van Dyck CH, Arnsten AFT. Localization of PDE4D, HCN1 channels, and mGluR3 in rhesus macaque entorhinal cortex may confer vulnerability in Alzheimer's disease. Cereb Cortex 2023; 33:11501-11516. [PMID: 37874022 PMCID: PMC10724870 DOI: 10.1093/cercor/bhad382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/28/2023] [Accepted: 09/27/2023] [Indexed: 10/25/2023] Open
Abstract
Alzheimer's disease cortical tau pathology initiates in the layer II cell clusters of entorhinal cortex, but it is not known why these specific neurons are so vulnerable. Aging macaques exhibit the same qualitative pattern of tau pathology as humans, including initial pathology in layer II entorhinal cortex clusters, and thus can inform etiological factors driving selective vulnerability. Macaque data have already shown that susceptible neurons in dorsolateral prefrontal cortex express a "signature of flexibility" near glutamate synapses on spines, where cAMP-PKA magnification of calcium signaling opens nearby potassium and hyperpolarization-activated cyclic nucleotide-gated channels to dynamically alter synapse strength. This process is regulated by PDE4A/D, mGluR3, and calbindin, to prevent toxic calcium actions; regulatory actions that are lost with age/inflammation, leading to tau phosphorylation. The current study examined whether a similar "signature of flexibility" expresses in layer II entorhinal cortex, investigating the localization of PDE4D, mGluR3, and HCN1 channels. Results showed a similar pattern to dorsolateral prefrontal cortex, with PDE4D and mGluR3 positioned to regulate internal calcium release near glutamate synapses, and HCN1 channels concentrated on spines. As layer II entorhinal cortex stellate cells do not express calbindin, even when young, they may be particularly vulnerable to magnified calcium actions and ensuing tau pathology.
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Affiliation(s)
- Dibyadeep Datta
- Departments of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Isabella Perone
- Departments of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Yury M Morozov
- Departments of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Jon Arellano
- Departments of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Alvaro Duque
- Departments of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Pasko Rakic
- Departments of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | | | - Amy F T Arnsten
- Departments of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
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3
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Sebastião AM, Ribeiro JA. Adjusting the brakes to adjust neuronal activity: Adenosinergic modulation of GABAergic transmission. Neuropharmacology 2023; 236:109600. [PMID: 37225084 DOI: 10.1016/j.neuropharm.2023.109600] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 04/20/2023] [Accepted: 05/16/2023] [Indexed: 05/26/2023]
Abstract
About 50 years elapsed from the publication of the first full paper on the neuromodulatory action of adenosine at a 'simple' synapse model, the neuromuscular junction (Ginsborg and Hirst, 1972). In that study adenosine was used as a tool to increase cyclic AMP and for the great surprise, it decreased rather than increased neurotransmitter release, and for a further surprise, its action was prevented by theophylline, at the time only known as inhibitor of phosphodiesterases. These intriguing observations opened the curiosity for immediate studies relating the action of adenine nucleotides, known to be released together with neurotransmitters, to that of adenosine (Ribeiro and Walker, 1973, 1975). Our understanding on the ways adenosine uses to modulate synapses, circuits, and brain activity, vastly expanded since then. However, except for A2A receptors, whose actions upon GABAergic neurons of the striatum are well known, most of the attention given to the neuromodulatory action of adenosine has been focusing upon excitatory synapses. Evidence is growing that GABAergic transmission is also a target for adenosinergic neuromodulation through A1 and A2A receptors. Some o these actions have specific time windows during brain development, and others are selective for specific GABAergic neurons. Both tonic and phasic GABAergic transmission can be affected, and either neurons or astrocytes can be targeted. In some cases, those effects result from a concerted action with other neuromodulators. Implications of these actions in the control of neuronal function/dysfunction will be the focus of this review.
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Affiliation(s)
- Ana M Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal.
| | - Joaquim Alexandre Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
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4
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Yi T, Wang N, Huang J, Wang Y, Ren S, Hu Y, Xia J, Liao Y, Li X, Luo F, Ouyang Q, Li Y, Zheng Z, Xiao Q, Ren R, Yao Z, Tang X, Wang Y, Chen X, He C, Li H, Hu Z. A Sleep-Specific Midbrain Target for Sevoflurane Anesthesia. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2300189. [PMID: 36961096 PMCID: PMC10214273 DOI: 10.1002/advs.202300189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/02/2023] [Indexed: 05/27/2023]
Abstract
Sevoflurane has been the most widely used inhaled anesthetics with a favorable recovery profile; however, the precise mechanisms underlying its anesthetic action are still not completely understood. Here the authors show that sevoflurane activates a cluster of urocortin 1 (UCN1+ )/cocaine- and amphetamine-regulated transcript (CART+ ) neurons in the midbrain involved in its anesthesia. Furthermore, growth hormone secretagogue receptor (GHSR) is highly enriched in sevoflurane-activated UCN1+ /CART+ cells and is necessary for sleep induction. Blockade of GHSR abolishes the excitatory effect of sevoflurane on UCN1+ /CART+ neurons and attenuates its anesthetic effect. Collectively, their data suggest that anesthetic action of sevoflurane necessitates the GHSR activation in midbrain UCN1+ /CART+ neurons, which provides a novel target including the nucleus and receptor in the field of anesthesia.
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Affiliation(s)
- Tingting Yi
- Department of AnesthesiologySecond Affiliated HospitalThird Military Medical UniversityChongqing400037China
- Department of AnesthesiologyYongchuan HospitalChongqing Medical UniversityChongqing402160China
| | - Na Wang
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
- College of BioengineeringChongqing UniversityChongqing400044China
| | - Jing Huang
- Department of AnesthesiologySecond Affiliated HospitalThird Military Medical UniversityChongqing400037China
| | - Yaling Wang
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Shuancheng Ren
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Yiwen Hu
- Department of AnesthesiologySecond Affiliated HospitalThird Military Medical UniversityChongqing400037China
| | - Jianxia Xia
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Yixiang Liao
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Xin Li
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Fenlan Luo
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Qin Ouyang
- School of PharmacyThird Military Medical UniversityChongqing400038China
| | - Yu Li
- Department of AnesthesiologySecond Affiliated HospitalThird Military Medical UniversityChongqing400037China
| | - Ziyi Zheng
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Qin Xiao
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Rong Ren
- Sleep Medicine CenterDepartment of Respiratory and Critical Care MedicineMental Health CenterWest China HospitalSichuan UniversityChengdu610041China
| | - Zhongxiang Yao
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Xiangdong Tang
- Sleep Medicine CenterDepartment of Respiratory and Critical Care MedicineMental Health CenterWest China HospitalSichuan UniversityChengdu610041China
| | - Yanjiang Wang
- Department of NeurologyDaping HospitalThird Military Medical UniversityChongqing400042China
| | - Xiaowei Chen
- Brain Research CenterCollaborative Innovation Center for Brain ScienceThird Military Medical UniversityChongqing400038China
| | - Chao He
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
| | - Hong Li
- Department of AnesthesiologySecond Affiliated HospitalThird Military Medical UniversityChongqing400037China
| | - Zhian Hu
- Department of PhysiologyThird Military Medical UniversityChongqing400038China
- College of BioengineeringChongqing UniversityChongqing400044China
- Chongqing Institute for Brain and IntelligenceGuangyang Bay LaboratoryChongqing400064China
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5
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Vasile F, Dossi E, Moulard J, Ezan P, Lecoin L, Cohen-Salmon M, Mailly P, Le Bert M, Couillin I, Bemelmans A, Rouach N. Pannexin 1 activity in astroglia sets hippocampal neuronal network patterns. PLoS Biol 2022; 20:e3001891. [PMID: 36477165 PMCID: PMC9728857 DOI: 10.1371/journal.pbio.3001891] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 10/24/2022] [Indexed: 12/12/2022] Open
Abstract
Astroglial release of molecules is thought to actively modulate neuronal activity, but the nature, release pathway, and cellular targets of these neuroactive molecules are still unclear. Pannexin 1, expressed by neurons and astrocytes, form nonselective large pore channels that mediate extracellular exchange of molecules. The functional relevance of these channels has been mostly studied in brain tissues, without considering their specific role in different cell types, or in neurons. Thus, our knowledge of astroglial pannexin 1 regulation and its control of neuronal activity remains very limited, largely due to the lack of tools targeting these channels in a cell-specific way. We here show that astroglial pannexin 1 expression in mice is developmentally regulated and that its activation is activity-dependent. Using astrocyte-specific molecular tools, we found that astroglial-specific pannexin 1 channel activation, in contrast to pannexin 1 activation in all cell types, selectively and negatively regulates hippocampal networks, with their disruption inducing a drastic switch from bursts to paroxysmal activity. This decrease in neuronal excitability occurs via an unconventional astroglial mechanism whereby pannexin 1 channel activity drives purinergic signaling-mediated regulation of hyperpolarisation-activated cyclic nucleotide (HCN)-gated channels. Our findings suggest that astroglial pannexin 1 channel activation serves as a negative feedback mechanism crucial for the inhibition of hippocampal neuronal networks.
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Affiliation(s)
- Flora Vasile
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
| | - Elena Dossi
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
| | - Julien Moulard
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
| | - Pascal Ezan
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
| | - Laure Lecoin
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
| | - Martine Cohen-Salmon
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
| | - Philippe Mailly
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
| | - Marc Le Bert
- CNRS UMR7355, Experimental and Molecular Immunology and Neurogenetics, Orleans, France
| | - Isabelle Couillin
- CNRS UMR7355, Experimental and Molecular Immunology and Neurogenetics, Orleans, France
| | - Alexis Bemelmans
- Université Paris-Saclay, Commissariat à l’Energie Atomique et aux Energies Alternatives, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, Fontenay-aux-Roses, France
| | - Nathalie Rouach
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Labex Memolife, PSL Research University, Paris, France
- * E-mail:
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6
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Hanalioglu S, Taskiran-Sag A, Karatas H, Donmez-Demir B, Yilmaz-Ozcan S, Eren-Kocak E, Gursoy-Ozdemir Y, Dalkara T. Cortical spreading depression can be triggered by sensory stimulation in primed wild type mouse brain: a mechanistic insight to migraine aura generation. J Headache Pain 2022; 23:107. [PMID: 35986251 PMCID: PMC9392331 DOI: 10.1186/s10194-022-01474-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 08/09/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Unlike the spontaneously appearing aura in migraineurs, experimentally, cortical spreading depression (CSD), the neurophysiological correlate of aura is induced by non-physiological stimuli. Consequently, neural mechanisms involved in spontaneous CSD generation, which may provide insight into how migraine starts in an otherwise healthy brain, remain largely unclear. We hypothesized that CSD can be physiologically induced by sensory stimulation in primed mouse brain.
Methods
Cortex was made susceptible to CSD with partial inhibition of Na+/K+-ATPase by epidural application of a low concentration of Na+/K+-ATPase blocker ouabain, allowing longer than 30-min intervals between CSDs or by knocking-down α2 subunit of Na+/K+-ATPase, which is crucial for K+ and glutamate re-uptake, with shRNA. Stimulation-triggered CSDs and extracellular K+ changes were monitored in vivo electrophysiologically and a K+-sensitive fluoroprobe (IPG-4), respectively.
Results
After priming with ouabain, photic stimulation significantly increased the CSD incidence compared with non-stimulated animals (44.0 vs. 4.9%, p < 0.001). Whisker stimulation also significantly increased the CSD incidence, albeit less effectively (14.9 vs. 2.4%, p = 0.02). Knocking-down Na+/K+-ATPase (50% decrease in mRNA) lowered the CSD threshold in all mice tested with KCl but triggered CSDs in 14.3% and 16.7% of mice with photic and whisker stimulation, respectively. Confirming Na+/K+-ATPase hypofunction, extracellular K+ significantly rose during sensory stimulation after ouabain or shRNA treatment unlike controls. In line with the higher CSD susceptibility observed, K+ rise was more prominent after ouabain. To gain insight to preventive mechanisms reducing the probability of stimulus-evoked CSDs, we applied an A1-receptor antagonist (DPCPX) to the occipital cortex, because adenosine formed during stimulation from ATP can reduce CSD susceptibility. DPCPX induced spontaneous CSDs but only small-DC shifts along with suppression of EEG spikes during photic stimulation, suggesting that the inhibition co-activated with sensory stimulation could limit CSD ignition when K+ uptake was not sufficiently suppressed as with ouabain.
Conclusions
Normal brain is well protected against CSD generation. For CSD to be ignited under physiological conditions, priming and predisposing factors are required as seen in migraine patients. Intense sensory stimulation has potential to trigger CSD when co-existing conditions bring extracellular K+ and glutamate concentrations over CSD-ignition threshold and stimulation-evoked inhibitory mechanisms are overcome.
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7
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Chen C, Lin Y, Cai F, Li J, Li H, Li X. Adenosine Downregulates the Activities of Glutamatergic Neurons in the Paraventricular Hypothalamic Nucleus Required for Sleep. Front Neurosci 2022; 16:907155. [PMID: 35769705 PMCID: PMC9236558 DOI: 10.3389/fnins.2022.907155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/24/2022] [Indexed: 11/13/2022] Open
Abstract
Adenosine is an endogenous substance that regulates sleep homeostasis. It plays an important role in sleep induction under physiological condition. So far, the neural mechanisms underlying sleep-promoting effects of adenosine are not completely clear. Recent studies have shown that glutamatergic neurons in the paraventricular hypothalamic nucleus (PVH) play an important role in wakefulness. Using whole-cell patch-clamp, we found that adenosine can inhibit glutamatergic neurons in PVH. This inhibition is mainly achieved by activating adenosine type 1 receptors, thereby reducing hyperpolarization-activated cyclic nucleotide-gated cation channels. By recording electroencephalogram (EEG) and electromyography (EMG), it was found that local administration of adenosine type 1 receptor blocker in PVH could significantly reduce the NREM sleep. On the contrary, if adenosine was given, it could increase the NREM sleep. These results suggest that adenosine can promote sleep by reducing the excitability of PVH neurons. This findings reveal a novel mechanism of adenosine regulating sleep homeostasis.
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Affiliation(s)
- Changlin Chen
- Department of Anesthesiology, The Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Yichen Lin
- Department of Vascular Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Feng Cai
- Department of Urology and Neurocardiothoracic Surgery, 927 Hospital of the Joint Logistics Support Force of the Chinese People’s Liberation Army, Pu’er, China
| | - Jinsui Li
- Department of Thyroid and Breast Surgery, The Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Haixun Li
- Department of Cardiovascular Surgery, The Third Affiliated Hospital of Zunyi Medical University, Zunyi, China
- *Correspondence: Haixun Li,
| | - Xiantao Li
- Department of Vascular Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
- Xiantao Li,
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8
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Chen ZH, Han YY, Shang YJ, Zhuang SY, Huang JN, Wu BY, Li CH. Cordycepin Ameliorates Synaptic Dysfunction and Dendrite Morphology Damage of Hippocampal CA1 via A1R in Cerebral Ischemia. Front Cell Neurosci 2022; 15:783478. [PMID: 35002628 PMCID: PMC8740211 DOI: 10.3389/fncel.2021.783478] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/01/2021] [Indexed: 01/18/2023] Open
Abstract
Cordycepin exerted significant neuroprotective effects and protected against cerebral ischemic damage. Learning and memory impairments after cerebral ischemia are common. Cordycepin has been proved to improve memory impairments induced by cerebral ischemia, but its underlying mechanism has not been revealed yet. The plasticity of synaptic structure and function is considered to be one of the neural mechanisms of learning and memory. Therefore, we investigated how cordycepin benefits dendritic morphology and synaptic transmission after cerebral ischemia and traced the related molecular mechanisms. The effects of cordycepin on the protection against ischemia were studied by using global cerebral ischemia (GCI) and oxygen-glucose deprivation (OGD) models. Behavioral long-term potentiation (LTP) and synaptic transmission were observed with electrophysiological recordings. The dendritic morphology and histological assessment were assessed by Golgi staining and hematoxylin-eosin (HE) staining, respectively. Adenosine A1 receptors (A1R) and adenosine A2A receptors (A2AR) were evaluated with western blotting. The results showed that cordycepin reduced the GCI-induced dendritic morphology scathing and behavioral LTP impairment in the hippocampal CA1 area, improved the learning and memory abilities, and up-regulated the level of A1R but not A2AR. In the in vitro experiments, cordycepin pre-perfusion could alleviate the hippocampal slices injury and synaptic transmission cripple induced by OGD, accompanied by increased adenosine content. In addition, the protective effect of cordycepin on OGD-induced synaptic transmission damage was eliminated by using an A1R antagonist instead of A2AR. These findings revealed that cordycepin alleviated synaptic dysfunction and dendritic injury in ischemic models by modulating A1R, which provides new insights into the pharmacological mechanisms of cordycepin for ameliorating cognitive impairment induced by cerebral ischemia.
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Affiliation(s)
- Zhao-Hui Chen
- School of Life Science, South China Normal University, Guangzhou, China
| | - Yuan-Yuan Han
- School of Life Science, South China Normal University, Guangzhou, China.,Panyu Central Hospital, Guangzhou, China
| | - Ying-Jie Shang
- School of Life Science, South China Normal University, Guangzhou, China
| | - Si-Yi Zhuang
- School of Life Science, South China Normal University, Guangzhou, China
| | - Jun-Ni Huang
- School of Life Science, South China Normal University, Guangzhou, China
| | - Bao-Yan Wu
- Ministry of Education (MOE) Key Laboratory of Laser Life Science, Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, China
| | - Chu-Hua Li
- School of Life Science, South China Normal University, Guangzhou, China
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9
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Growth of dendritic structures on the surface of copper selenide thin films. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.127157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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10
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Input-selective adenosine A 1 receptor-mediated synaptic depression of excitatory transmission in dorsal striatum. Sci Rep 2021; 11:6345. [PMID: 33737568 PMCID: PMC7973535 DOI: 10.1038/s41598-021-85513-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 03/02/2021] [Indexed: 01/31/2023] Open
Abstract
The medial (DMS) and lateral (DLS) dorsal striatum differentially drive goal-directed and habitual/compulsive behaviors, respectively, and are implicated in a variety of neuropsychiatric disorders. These subregions receive distinct inputs from cortical and thalamic regions which uniquely determine dorsal striatal activity and function. Adenosine A1 receptors (A1Rs) are prolific within striatum and regulate excitatory glutamate transmission. Thus, A1Rs may have regionally-specific effects on neuroadaptive processes which may ultimately influence striatally-mediated behaviors. The occurrence of A1R-driven plasticity at specific excitatory inputs to dorsal striatum is currently unknown. To better understand how A1Rs may influence these behaviors, we first sought to understand how A1Rs modulate these distinct inputs. We evaluated A1R-mediated inhibition of cortico- and thalamostriatal transmission using in vitro whole-cell, patch clamp slice electrophysiology recordings in medium spiny neurons from both the DLS and DMS of C57BL/6J mice in conjunction with optogenetic approaches. In addition, conditional A1R KO mice lacking A1Rs at specific striatal inputs to DMS and DLS were generated to directly determine the role of these presynaptic A1Rs on the measured electrophysiological responses. Activation of presynaptic A1Rs produced significant and prolonged synaptic depression (A1R-SD) of excitatory transmission in the both the DLS and DMS of male and female animals. Our findings indicate that A1R-SD at corticostriatal and thalamostriatal inputs to DLS can be additive and that A1R-SD in DMS occurs primarily at thalamostriatal inputs. These findings advance the field's understanding of the functional roles of A1Rs in striatum and implicate their potential contribution to neuropsychiatric diseases.
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11
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Therapeutic potential of targeting G protein-gated inwardly rectifying potassium (GIRK) channels in the central nervous system. Pharmacol Ther 2021; 223:107808. [PMID: 33476640 DOI: 10.1016/j.pharmthera.2021.107808] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 01/05/2021] [Indexed: 12/15/2022]
Abstract
G protein-gated inwardly rectifying potassium channels (Kir3/GirK) are important for maintaining resting membrane potential, cell excitability and inhibitory neurotransmission. Coupled to numerous G protein-coupled receptors (GPCRs), they mediate the effects of many neurotransmitters, neuromodulators and hormones contributing to the general homeostasis and particular synaptic plasticity processes, learning, memory and pain signaling. A growing number of behavioral and genetic studies suggest a critical role for the appropriate functioning of the central nervous system, as well as their involvement in many neurologic and psychiatric conditions, such as neurodegenerative diseases, mood disorders, attention deficit hyperactivity disorder, schizophrenia, epilepsy, alcoholism and drug addiction. Hence, GirK channels emerge as a very promising tool to be targeted in the current scenario where these conditions already are or will become a global public health problem. This review examines recent findings on the physiology, function, dysfunction, and pharmacology of GirK channels in the central nervous system and highlights the relevance of GirK channels as a worthful potential target to improve therapies for related diseases.
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12
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Activity- and pH-dependent adenosine shifts at the end of a focal seizure in the entorhinal cortex. Epilepsy Res 2020; 165:106401. [PMID: 32599416 DOI: 10.1016/j.eplepsyres.2020.106401] [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: 03/05/2020] [Revised: 06/05/2020] [Accepted: 06/14/2020] [Indexed: 11/24/2022]
Abstract
Adenosine (ADO) is an endogenous modulator of neuronal excitability, with anticonvulsant and neuroprotective effects. It has been proposed that the activity-dependent release of ADO promoted by the extracellular acidification occurring during seizures contributes to seizure termination. To verify this hypothesis, we recorded field potentials, pH and ADO changes measured with enzymatic biosensors during acute focal seizures in the medial entorhinal cortex (mEC) of the isolated guinea-pig brain maintained in vitro. The effect of ADO on seizure-like events (SLEs) induced by GABAa receptor antagonism with bicuculline methiodide (BMI; 50 μM) was assessed by arterial applications of 1 mM ADO. ADO either reduced or prevented epileptiform activity. The A1 receptor antagonist DPCPX (100-500 μM) prolonged BMI-induced seizures and was able to precipitate SLEs in the absence of proconvulsant. Simultaneous recordings of brain activity, extracellular ADO and pH shifts demonstrated that ADO decreases at the onset and progressively rises toward the end of SLEs induced by either BMI or 4-aminopyridine (4AP; 50 μM), reaching maximal values 1-5 min after SLE termination. ADO changes were preceded by a SLE-dependent extracellular acid shift. Both pH acidification and ADO changes were abolished by 22 mM HEPES in the arterial perfusate. In these conditions, SLE duration was prolonged. Our data confirm that ADO plays a role in regulating brain excitability. Its increase depends on seizure-induced acid pH shift and it is maximal after the end of the SLE. These findings strongly suggest that ADO contributes to termination of focal seizures and to the establishment of the postictal depression.
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Adenosine Signaling through A1 Receptors Inhibits Chemosensitive Neurons in the Retrotrapezoid Nucleus. eNeuro 2018; 5:eN-NWR-0404-18. [PMID: 30627640 PMCID: PMC6325544 DOI: 10.1523/eneuro.0404-18.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/13/2018] [Accepted: 11/16/2018] [Indexed: 01/01/2023] Open
Abstract
A subset of neurons in the retrotrapezoid nucleus (RTN) function as respiratory chemoreceptors by regulating depth and frequency of breathing in response to changes in tissue CO2/H+. The activity of chemosensitive RTN neurons is also subject to modulation by CO2/H+-dependent purinergic signaling. However, mechanisms contributing to purinergic regulation of RTN chemoreceptors are not entirely clear. Recent evidence suggests adenosine inhibits RTN chemoreception in vivo by activation of A1 receptors. The goal of this study was to characterize effects of adenosine on chemosensitive RTN neurons and identify intrinsic and synaptic mechanisms underlying this response. Cell-attached recordings from RTN chemoreceptors in slices from rat or wild-type mouse pups (mixed sex) show that exposure to adenosine (1 µM) inhibits chemoreceptor activity by an A1 receptor-dependent mechanism. However, exposure to a selective A1 receptor antagonist (8-cyclopentyl-1,3-dipropylxanthine, DPCPX; 30 nM) alone did not potentiate CO2/H+-stimulated activity, suggesting activation of A1 receptors does not limit chemoreceptor activity under these reduced conditions. Whole-cell voltage-clamp from chemosensitive RTN neurons shows that exposure to adenosine activated an inward rectifying K+ conductance, and at the network level, adenosine preferentially decreased frequency of EPSCs but not IPSCs. These results show that adenosine activation of A1 receptors inhibits chemosensitive RTN neurons by direct activation of a G-protein-regulated inward-rectifier K+ (GIRK)-like conductance, and presynaptically, by suppression of excitatory synaptic input to chemoreceptors.
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14
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Tubi MA, Lutkenhoff E, Blanco MB, McArthur D, Villablanca P, Ellingson B, Diaz-Arrastia R, Van Ness P, Real C, Shrestha V, Engel J, Vespa PM. Early seizures and temporal lobe trauma predict post-traumatic epilepsy: A longitudinal study. Neurobiol Dis 2018; 123:115-121. [PMID: 29859872 DOI: 10.1016/j.nbd.2018.05.014] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 05/29/2018] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE Injury severity after traumatic brain injury (TBI) is a well-established risk factor for the development of post-traumatic epilepsy (PTE). However, whether lesion location influences the susceptibility of seizures and development of PTE longitudinally has yet to be defined. We hypothesized that lesion location, specifically in the temporal lobe, would be associated with an increased incidence of both early seizures and PTE. As secondary analysis measures, we assessed the degree of brain atrophy and functional recovery, and performed a between-group analysis, comparing patients who developed PTE with those who did not develop PTE. METHODS We assessed early seizure incidence (n = 90) and longitudinal development of PTE (n = 46) in a prospective convenience sample of patients with moderate-severe TBI. Acutely, patients were monitored with prospective cEEG and a high-resolution Magnetic Resonance Imaging (MRI) scan for lesion location classification. Chronically, patients underwent a high-resolution MRI, clinical assessment, and were longitudinally monitored for development of epilepsy for a minimum of 2 years post-injury. RESULTS Early seizures, occurring within the first week post-injury, occurred in 26.7% of the patients (n = 90). Within the cohort of subjects who had evidence of early seizures (n = 24), 75% had a hemorrhagic temporal lobe injury on admission. For longitudinal analyses (n = 46), 45.7% of patients developed PTE within a minimum of 2 years post-injury. Within the cohort of subjects who developed PTE (n = 21), 85.7% had a hemorrhagic temporal lobe injury on admission and 38.1% had early (convulsive or non-convulsive) seizures on cEEG monitoring during their acute ICU stay. In a between-group analysis, patients with PTE (n = 21) were more likely than patients who did not develop PTE (n = 25) to have a hemorrhagic temporal lobe injury (p < 0.001), worse functional recovery (p = 0.003), and greater temporal lobe atrophy (p = 0.029). CONCLUSION Our results indicate that in a cohort of patients with a moderate-severe TBI, 1) lesion location specificity (e.g. the temporal lobe) is related to both a high incidence of early seizures and longitudinal development of PTE, 2) early seizures, whether convulsive or non-convulsive in nature, are associated with an increased risk for PTE development, and 3) patients who develop PTE have greater chronic temporal lobe atrophy and worse functional outcomes, compared to those who do not develop PTE, despite matched injury severity characteristics. This study provides the foundation for a future prospective study focused on elucidating the mechanisms and risk factors for epileptogenesis.
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Affiliation(s)
- Meral A Tubi
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, USC Keck School of Medicine, United States
| | | | | | | | | | | | | | - Paul Van Ness
- Department of Neurology and Neurophysiology, Baylor College of Medicine, United States
| | - Courtney Real
- David Geffen School of Medicine at UCLA, United States
| | | | - Jerome Engel
- David Geffen School of Medicine at UCLA, United States
| | - Paul M Vespa
- David Geffen School of Medicine at UCLA, United States.
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15
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Lee ST, Venton BJ. Regional Variations of Spontaneous, Transient Adenosine Release in Brain Slices. ACS Chem Neurosci 2018; 9:505-513. [PMID: 29135225 DOI: 10.1021/acschemneuro.7b00280] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Transient adenosine signaling has been recently discovered in vivo, where the concentration is on average 180 nM and the duration only 3-4 s. In order to rapidly screen different brain regions and mechanisms of formation and regulation, here we develop a rat brain slice model to study adenosine transients. The frequency, concentration, and duration of transient adenosine events were compared in the prefrontal cortex (PFC), hippocampus (CA1), and thalamus. Adenosine transients in the PFC were similar to those in vivo, with a concentration of 160 ± 10 nM, and occurred frequently, averaging one every 50 ± 5 s. In the thalamus, transients were infrequent, occurring every 280 ± 40 s, and lower concentration (110 ± 10 nM), but lasted twice as long as in the PFC. In the hippocampus, adenosine transients were less frequent than those in the PFC, occurring every 79 ± 7 s, but the average concentration (240 ± 20 nM) was significantly higher. Adenosine transients are largely maintained after applying 200 nM tetrodotoxin, implying they are not activity dependent. The response to adenosine A1 antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) differed by region; DPCPX had no significant effects in the PFC, but increased the average transient concentration in the thalamus and both the transient frequency and concentration in the hippocampus. Thus, the amount of adenosine available to activate receptors, and the ability to upregulate adenosine signaling with DPCPX, varies by brain region. This is an important consideration for designing treatments that modulate adenosine in order to cause neuroprotective effects.
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Affiliation(s)
- Scott T. Lee
- Department of Chemistry, University of Virginia, PO Box 400319, Charlottesville, Virginia 22901, United States
| | - B. Jill Venton
- Department of Chemistry, University of Virginia, PO Box 400319, Charlottesville, Virginia 22901, United States
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16
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Kerkhofs A, Xavier AC, da Silva BS, Canas PM, Idema S, Baayen JC, Ferreira SG, Cunha RA, Mansvelder HD. Caffeine Controls Glutamatergic Synaptic Transmission and Pyramidal Neuron Excitability in Human Neocortex. Front Pharmacol 2018; 8:899. [PMID: 29354052 PMCID: PMC5758559 DOI: 10.3389/fphar.2017.00899] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Accepted: 11/27/2017] [Indexed: 12/13/2022] Open
Abstract
Caffeine is the most widely used psychoactive drug, bolstering attention and normalizing mood and cognition, all functions involving cerebral cortical circuits. Whereas studies in rodents showed that caffeine acts through the antagonism of inhibitory A1 adenosine receptors (A1R), neither the role of A1R nor the impact of caffeine on human cortical neurons is known. We here provide the first characterization of the impact of realistic concentrations of caffeine experienced by moderate coffee drinkers (50 μM) on excitability of pyramidal neurons and excitatory synaptic transmission in the human temporal cortex. Moderate concentrations of caffeine disinhibited several of the inhibitory A1R-mediated effects of adenosine, similar to previous observations in the rodent brain. Thus, caffeine restored the adenosine-induced decrease of both intrinsic membrane excitability and excitatory synaptic transmission in the human pyramidal neurons through antagonism of post-synaptic A1R. Indeed, the A1R-mediated effects of endogenous adenosine were more efficient to inhibit synaptic transmission than neuronal excitability. This was associated with a distinct affinity of caffeine for synaptic versus extra-synaptic human cortical A1R, probably resulting from a different molecular organization of A1R in human cortical synapses. These findings constitute the first neurophysiological description of the impact of caffeine on pyramidal neuron excitability and excitatory synaptic transmission in the human temporal cortex, providing adequate ground for the effects of caffeine on cognition in humans.
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Affiliation(s)
- Amber Kerkhofs
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Ana C Xavier
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Beatriz S da Silva
- Portuguese National Institute of Legal Medicine and Forensic Sciences, Coimbra, Portugal
| | - Paula M Canas
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Sander Idema
- Department of Neurosurgery, Neuroscience Amsterdam, VU University Medical Center Amsterdam, Amsterdam, Netherlands
| | - Johannes C Baayen
- Department of Neurosurgery, Neuroscience Amsterdam, VU University Medical Center Amsterdam, Amsterdam, Netherlands
| | - Samira G Ferreira
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Rodrigo A Cunha
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Neuroscience Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
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17
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Wu L, Meng J, Shen Q, Zhang Y, Pan S, Chen Z, Zhu LQ, Lu Y, Huang Y, Zhang G. Caffeine inhibits hypothalamic A 1R to excite oxytocin neuron and ameliorate dietary obesity in mice. Nat Commun 2017; 8:15904. [PMID: 28654087 PMCID: PMC5490268 DOI: 10.1038/ncomms15904] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 05/10/2017] [Indexed: 12/14/2022] Open
Abstract
Caffeine, an antagonist of the adenosine receptor A1R, is used as a dietary supplement to reduce body weight, although the underlying mechanism is unclear. Here, we report that adenosine level in the cerebrospinal fluid, and hypothalamic expression of A1R, are increased in the diet-induced obesity (DIO) mouse. We find that mice with overexpression of A1R in the neurons of paraventricular nucleus (PVN) of the hypothalamus are hyperphagic, have glucose intolerance and high body weight. Central or peripheral administration of caffeine reduces the body weight of DIO mice by the suppression of appetite and increasing of energy expenditure. We also show that caffeine excites oxytocin expressing neurons, and blockade of the action of oxytocin significantly attenuates the effect of caffeine on energy balance. These data suggest that caffeine inhibits A1Rs expressed on PVN oxytocin neurons to negatively regulate energy balance in DIO mice.
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Affiliation(s)
- Liufeng Wu
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Jia Meng
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Qing Shen
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Yi Zhang
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Susu Pan
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Zhuo Chen
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Ling-Qiang Zhu
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.,Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Youming Lu
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.,Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Yuan Huang
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Guo Zhang
- Key Laboratory of Environmental Health, Ministry of Education, Department of Toxicology, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.,Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
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18
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A1 Adenosine Receptor Activation Modulates Central Nervous System Development and Repair. Mol Neurobiol 2016; 54:8128-8139. [DOI: 10.1007/s12035-016-0292-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 11/08/2016] [Indexed: 01/22/2023]
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19
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Propofol postsynaptically suppresses stellate neuron excitability in the entorhinal cortex by influencing the HCN and TREK-2 channels. Neurosci Lett 2016; 619:54-9. [DOI: 10.1016/j.neulet.2016.03.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 03/05/2016] [Accepted: 03/07/2016] [Indexed: 11/22/2022]
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20
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Xie M, Li C, He C, Yang L, Tan G, Yan J, Wang J, Hu Z. Short-term sleep deprivation disrupts the molecular composition of ionotropic glutamate receptors in entorhinal cortex and impairs the rat spatial reference memory. Behav Brain Res 2015; 300:70-6. [PMID: 26455878 DOI: 10.1016/j.bbr.2015.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/28/2015] [Accepted: 10/02/2015] [Indexed: 12/27/2022]
Abstract
Numerous studies reported that sleep deprivation (SD) causes impairment in spatial cognitive performance. However, the molecular mechanisms affected by SD underlying this behavioral phenomenon remain elusive. Here, we focused on the entorhinal cortex (EC), the gateway of the hippocampus, and investigated how SD affected the subunit expression of AMPARs and NMDARs, the main ionotropic glutamategic receptors serving a pivotal role in spatial cognition. In EC, we found 4h SD remarkably reduced surface expression of GluA1, while there was an increase in the surface expression of GluA2 and GluA3. As for NMDARs, SD with short duration significantly reduced the surface expression levels of GluN1 and GluN2B without effect on the GluN2A. In parallel with the alterations in AMPARs and NMDARs, we found the 4h SD impaired rat spatial reference memory as assessed by Morris water maze task. Overall, these data indicate that brief SD differently affects the AMPAR and NMDAR subunit expressions in EC and might consequently disrupt the composition and functional properties of these receptors.
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Affiliation(s)
- Meilan Xie
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China
| | - Chao Li
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China
| | - Chao He
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China
| | - Li Yang
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China
| | - Gang Tan
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China
| | - Jie Yan
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China
| | - Jiali Wang
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China.
| | - Zhian Hu
- Department of Physiology, Collaborative Innovation Center for Brain Science, Third Military Medical University, Chongqing 400038 PR China.
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21
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He C, Luo F, Chen X, Chen F, Li C, Ren S, Qiao Q, Zhang J, de Lecea L, Gao D, Hu Z. Superficial Layer-Specific Histaminergic Modulation of Medial Entorhinal Cortex Required for Spatial Learning. Cereb Cortex 2015; 26:1590-1608. [PMID: 25595181 DOI: 10.1093/cercor/bhu322] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The medial entorhinal cortex (MEC) plays a crucial role in spatial learning and memory. Whereas the MEC receives a dense histaminergic innervation from the tuberomamillary nucleus of the hypothalamus, the functions of histamine in this brain region remain unclear. Here, we show that histamine acts via H1Rs to directly depolarize the principal neurons in the superficial, but not deep, layers of the MEC when recording at somata. Moreover, histamine decreases the spontaneous GABA, but not glutamate, release onto principal neurons in the superficial layers by acting at presynaptic H3Rs without effect on synaptic release in the deep layers. Histamine-induced depolarization is mediated via inhibition of Kir channels and requires the activation of protein kinase C, whereas the inhibition of spontaneous GABA release by histamine depends on voltage-gated Ca(2+) channels and extracellular Ca(2+). Furthermore, microinjection of the H1R or H3R, but not H2R, antagonist respectively into the superficial, but not deep, layers of MEC impairs rat spatial learning as assessed by water maze tasks but does not affect the motor function and exploratory activity in an open field. Together, our study indicates that histamine plays an essential role in spatial learning by selectively regulating neuronal excitability and synaptic transmission in the superficial layers of the MEC.
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Affiliation(s)
- Chao He
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Fenlan Luo
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Xingshu Chen
- Department of Histology and Embryology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Fang Chen
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Chao Li
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Shuancheng Ren
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Qicheng Qiao
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Jun Zhang
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Luis de Lecea
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA 94304, USA
| | - Dong Gao
- Department of Sleep and Psychology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
| | - Zhian Hu
- Department of Physiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China
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22
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Kumar D, Thakur MK. Perinatal exposure to bisphenol-A impairs spatial memory through upregulation of neurexin1 and neuroligin3 expression in male mouse brain. PLoS One 2014; 9:e110482. [PMID: 25330104 PMCID: PMC4201550 DOI: 10.1371/journal.pone.0110482] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 09/21/2014] [Indexed: 11/19/2022] Open
Abstract
Bisphenol-A (BPA), a well known endocrine disruptor, impairs learning and memory in rodents. However, the underlying molecular mechanism of BPA induced impairment in learning and memory is not well known. As synaptic plasticity is the cellular basis of memory, the present study investigated the effect of perinatal exposure to BPA on the expression of synaptic proteins neurexin1 (Nrxn1) and neuroligin3 (Nlgn3), dendritic spine density and spatial memory in postnatal male mice. The pregnant mice were orally administered BPA (50 µg/kgbw/d) from gestation day (GD) 7 to postnatal day (PND) 21 and sesame oil was used as a vehicle control. In Morris water maze (MWM) test, BPA extended the escape latency time to locate the hidden platform in 8 weeks male mice. RT-PCR and Immunoblotting results showed significant upregulation of Nrxn1 and Nlgn3 expression in both cerebral cortex and hippocampus of 3 and 8 weeks male mice. This was further substantiated by in-situ hybridization and immunofluorescence techniques. BPA also significantly increased the density of dendritic spines in both regions, as analyzed by rapid Golgi staining. Thus our data suggest that perinatal exposure to BPA impairs spatial memory through upregulation of expression of synaptic proteins Nrxn1 and Nlgn3 and increased dendritic spine density in cerebral cortex and hippocampus of postnatal male mice.
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Affiliation(s)
- Dhiraj Kumar
- Biochemistry and Molecular Biology Laboratory, Brain Research Centre, Department of Zoology, Banaras Hindu University, Varanasi, India
| | - Mahendra Kumar Thakur
- Biochemistry and Molecular Biology Laboratory, Brain Research Centre, Department of Zoology, Banaras Hindu University, Varanasi, India
- * E-mail:
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Miranda MF, Hamani C, de Almeida ACG, Amorim BO, Macedo CE, Fernandes MJS, Nobrega JN, Aarão MC, Madureira AP, Rodrigues AM, Andersen ML, Tufik S, Mello LE, Covolan L. Role of adenosine in the antiepileptic effects of deep brain stimulation. Front Cell Neurosci 2014; 8:312. [PMID: 25324724 PMCID: PMC4183090 DOI: 10.3389/fncel.2014.00312] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Accepted: 09/17/2014] [Indexed: 12/20/2022] Open
Abstract
Despite the effectiveness of anterior thalamic nucleus (AN) deep brain stimulation (DBS) for the treatment of epilepsy, mechanisms responsible for the antiepileptic effects of this therapy remain elusive. As adenosine modulates neuronal excitability and seizure activity in animal models, we hypothesized that this nucleoside could be one of the substrates involved in the effects of AN DBS. We applied 5 days of stimulation to rats rendered chronically epileptic by pilocarpine injections and recorded epileptiform activity in hippocampal slices. We found that slices from animals given DBS had reduced hippocampal excitability and were less susceptible to develop ictal activity. In live animals, AN DBS significantly increased adenosine levels in the hippocampus as measured by microdialysis. The reduced excitability of DBS in vitro was completely abolished in animals pre-treated with A1 receptor antagonists and was strongly potentiated by A1 receptor agonists. We conclude that some of the antiepileptic effects of DBS may be mediated by adenosine.
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Affiliation(s)
- Maisa F Miranda
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Clement Hamani
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil ; Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health Toronto, Canada ; Division of Neurosurgery, Toronto Western Hospital, University of Toronto Toronto, Canada
| | - Antônio-Carlos G de Almeida
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Beatriz O Amorim
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Carlos E Macedo
- Departamento de Psicobiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Maria José S Fernandes
- Disciplina de Neurologia Experimental, Universidade Federal de São Paulo São Paulo, Brazil
| | - José N Nobrega
- Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health Toronto, Canada
| | - Mayra C Aarão
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Ana Paula Madureira
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Antônio M Rodrigues
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Monica L Andersen
- Departamento de Psicobiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Sergio Tufik
- Departamento de Psicobiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Luiz E Mello
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Luciene Covolan
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil
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24
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Chen Z, Li Y, Liu R, Gao D, Chen Q, Hu Z, Guo J. Effects of interface pressure distribution on human sleep quality. PLoS One 2014; 9:e99969. [PMID: 24924427 PMCID: PMC4055748 DOI: 10.1371/journal.pone.0099969] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 05/20/2014] [Indexed: 02/02/2023] Open
Abstract
High sleep quality promotes efficient performance in the following day. Sleep quality is influenced by environmental factors, such as temperature, light, sound and smell. Here, we investigated whether differences in the interface pressure distribution on healthy individuals during sleep influenced sleep quality. We defined four types of pressure models by differences in the area distribution and the subjective feelings that occurred when participants slept on the mattresses. One type of model was showed "over-concentrated" distribution of pressure; one was displayed "over-evenly" distributed interface pressure while the other two models were displayed intermediate distribution of pressure. A polysomnography analysis demonstrated an increase in duration and proportion of non-rapid-eye-movement sleep stages 3 and 4, as well as decreased number of micro-arousals, in subjects sleeping on models with pressure intermediately distributed compared to models with over-concentrated or over-even distribution of pressure. Similarly, higher scores of self-reported sleep quality were obtained in subjects sleeping on the two models with intermediate pressure distribution. Thus, pressure distribution, at least to some degree, influences sleep quality and self-reported feelings of sleep-related events, though the underlying mechanisms remain unknown. The regulation of pressure models imposed by external sleep environment may be a new direction for improving sleep quality. Only an appropriate interface pressure distribution is beneficial for improving sleep quality, over-concentrated or -even distribution of pressure do not help for good sleep.
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Affiliation(s)
- Zongyong Chen
- Sleep Research Center, DaZiRan Science and Technology Ltd., Guiyang, Guizhou, China
| | - Yuqian Li
- Sleep Research Center, DaZiRan Science and Technology Ltd., Guiyang, Guizhou, China
| | - Rong Liu
- Sleep Research Center, DaZiRan Science and Technology Ltd., Guiyang, Guizhou, China
| | - Dong Gao
- Department of Sleep and Psychology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Quanhui Chen
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Zhian Hu
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Jiajun Guo
- Sleep Research Center, DaZiRan Science and Technology Ltd., Guiyang, Guizhou, China
- Department of Physiology, Third Military Medical University, Chongqing, China
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25
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He C, Chen F, Li B, Hu Z. Neurophysiology of HCN channels: From cellular functions to multiple regulations. Prog Neurobiol 2014; 112:1-23. [DOI: 10.1016/j.pneurobio.2013.10.001] [Citation(s) in RCA: 230] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 10/01/2013] [Accepted: 10/07/2013] [Indexed: 12/18/2022]
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26
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Xiong J, He C, Li C, Tan G, Li J, Yu Z, Hu Z, Chen F. Changes of dendritic spine density and morphology in the superficial layers of the medial entorhinal cortex induced by extremely low-frequency magnetic field exposure. PLoS One 2013; 8:e83561. [PMID: 24376717 PMCID: PMC3869808 DOI: 10.1371/journal.pone.0083561] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 11/09/2013] [Indexed: 01/20/2023] Open
Abstract
In the present study, we investigated the effects of chronic exposure (14 and 28 days) to a 0.5 mT 50 Hz extremely low-frequency magnetic field (ELM) on the dendritic spine density and shape in the superficial layers of the medial entorhinal cortex (MEC). We performed Golgi staining to reveal the dendritic spines of the principal neurons in rats. The results showed that ELM exposure induced a decrease in the spine density in the dendrites of stellate neurons and the basal dendrites of pyramidal neurons at both 14 days and 28 days, which was largely due to the loss of the thin and branched spines. The alteration in the density of mushroom and stubby spines post ELM exposure was cell-type specific. For the stellate neurons, ELM exposure slightly increased the density of stubby spines at 28 days, while it did not affect the density of mushroom spines at the same time. In the basal dendrites of pyramidal neurons, we observed a significant decrease in the mushroom spine density only at the later time point post ELM exposure, while the stubby spine density was reduced at 14 days and partially restored at 28 days post ELM exposure. ELM exposure-induced reduction in the spine density in the apical dendrites of pyramidal neurons was only observed at 28 days, reflecting the distinct vulnerability of spines in the apical and basal dendrites. Considering the changes in spine number and shape are involved in synaptic plasticity and the MEC is a part of neural network that is closely related to learning and memory, these findings may be helpful for explaining the ELM exposure-induced impairment in cognitive functions.
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Affiliation(s)
- Jiaxiang Xiong
- Department of Physiology, Third Military Medical University, Chongqing, PR China
| | - Chao He
- Department of Physiology, Third Military Medical University, Chongqing, PR China
| | - Chao Li
- Department of Physiology, Third Military Medical University, Chongqing, PR China
| | - Gang Tan
- Department of Physiology, Third Military Medical University, Chongqing, PR China
| | - Jingcheng Li
- Department of Physiology, Third Military Medical University, Chongqing, PR China
| | - Zhengping Yu
- Department of Occupational Health, Third Military Medical University, Chongqing, PR China
| | - Zhian Hu
- Department of Physiology, Third Military Medical University, Chongqing, PR China
- * E-mail: (ZH); (FC)
| | - Fang Chen
- Department of Physiology, Third Military Medical University, Chongqing, PR China
- * E-mail: (ZH); (FC)
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27
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Abstract
The neuromodulator adenosine is widely considered to be a key regulator of sleep homeostasis and an indicator of sleep need. Although the effect of adenosine on subcortical areas has been previously described, the effects on cortical neurons have not been addressed systematically to date. To that purpose, we performed in vitro whole-cell patch-clamp recordings and biocytin staining of pyramidal neurons and interneurons throughout all layers of rat prefrontal and somatosensory cortex, followed by morphological analysis. We found that adenosine, via the A1 receptor, exerts differential effects depending on neuronal cell type and laminar location. Interneurons and pyramidal neurons in layer 2 and a subpopulation of layer 3 pyramidal neurons that displayed regular spiking were insensitive to adenosine application, whereas other pyramidal cells in layers 3-6 were hyperpolarized (range 1.2-10.8 mV). Broad tufted pyramidal neurons with little spike adaptation showed a small adenosine response, whereas slender tufted pyramidal neurons with substantial adaptation showed a bigger response. These studies of the action of adenosine at the postsynaptic level may contribute to the understanding of the changes in cortical circuit functioning that take place between sleep and awakening.
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Affiliation(s)
- Karlijn I van Aerde
- Forschungszentrum Jülich, Institute of Neuroscience and Medicine, INM-2, D-52425 Jülich, Germany Current address: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Science, 1105 BA Amsterdam, The Netherlands
| | - Guanxiao Qi
- Forschungszentrum Jülich, Institute of Neuroscience and Medicine, INM-2, D-52425 Jülich, Germany Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Medical School, D-52074 Aachen, Germany
| | - Dirk Feldmeyer
- Forschungszentrum Jülich, Institute of Neuroscience and Medicine, INM-2, D-52425 Jülich, Germany Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Medical School, D-52074 Aachen, Germany JARA-Translational Brain Medicine, Aachen, Germany
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28
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Yan J, He C, Xia JX, Zhang D, Hu ZA. Orexin-A excites pyramidal neurons in layer 2/3 of the rat prefrontal cortex. Neurosci Lett 2012; 520:92-7. [PMID: 22617634 DOI: 10.1016/j.neulet.2012.05.038] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 04/23/2012] [Accepted: 05/10/2012] [Indexed: 10/28/2022]
Abstract
The arousal peptides, orexins, play an important role in regulating the function of the prefrontal cortex (PFC). Although orexins have been shown to increase the excitability of deep-layer neurons in the medial prefrontal cortex (mPFC), little is known about their effect on layer 2/3, the main intracortical processing layer. In this study, we investigated the effect of orexin-A on pyramidal neurons in layer 2/3 of the mPFC using whole-cell recordings in rat brain slices. We observed that orexin-A reversibly depolarized layer 2/3 pyramidal neurons through a postsynaptic action. This depolarization was concentration-dependent and mediated via orexin receptor 1. In voltage-clamp recordings, the orexin-A-induced current was reduced by the replacement of internal K(+) with Cs(+), removal of external Na(+), or an application of flufenamic acid (an inhibitor of nonselective cation channels). A blocker of Na(+)/Ca(2+) exchangers (SN-6) did not influence the excitatory effect of orexin-A. Moreover, the current induced by orexin-A reversed near E(k) when the external solution contained low levels of Na(+). When recording with Cs(+)-containing pipettes in normal external solution, the reversal potential of the current was approximately -25 mV. These data suggest an involvement of both K(+) channels and nonselective cation channels in the effect of orexin-A. The direct excitatory action of orexin-A on layer 2/3 mPFC neurons may contribute to the modulation of PFC activity, and play a role in cognitive arousal.
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Affiliation(s)
- Jie Yan
- Department of Physiology, Third Military Medical University, Chongqing, PR China
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29
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Hargus NJ, Jennings C, Perez-Reyes E, Bertram EH, Patel MK. Enhanced actions of adenosine in medial entorhinal cortex layer II stellate neurons in temporal lobe epilepsy are mediated via A(1)-receptor activation. Epilepsia 2011; 53:168-76. [PMID: 22126400 DOI: 10.1111/j.1528-1167.2011.03337.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE The adenosinergic system is known to exert an inhibitory affect in the brain, and as such adenosine has been considered an endogenous anticonvulsant. Entorhinal cortex (EC) layer II neurons, which serve as the primary input to the hippocampus, are spared in temporal lobe epilepsy (TLE) and become hyperexcitable. Because these neurons also express adenosine receptors, the activity of these neurons may be controlled by adenosine, specifically during seizure activity when adenosine levels are thought to rise. In light of this, we determined if the actions of adenosine on medial EC (mEC) layer II stellate neurons are augmented in TLE and by which receptor subtype. METHODS Horizontal brain slices were prepared from rats exhibiting spontaneous seizures (TLE) induced by electrical stimulation and compared with age-matched control rats. mEC layer II stellate neurons were visually identified, and action potentials (APs) were evoked either by a series of depolarizing current injection steps or via presynaptic stimulation of mEC deep layers. The effects of adenosine were compared with actions of adenosine A(1) and A(2A) receptor-specific agonists (CPA and CGS-21680) and antagonists (DPCPX and ZM-241385), respectively. Immunohistochemical and qPCR techniques were also employed to assess relative adenosine A(1)-receptor message and expression. KEY FINDINGS mEC layer II stellate neurons were hyperexcitable in TLE, evoking a higher frequency of APs when depolarized and generating bursts of APs when synaptically stimulated. Adenosine reduced AP frequency and synaptically evoked APs in a dose-dependent manner (500 nM-100 μM); however, in TLE, the inhibitory actions of adenosine occurred at concentrations that were without affect in control neurons. In both cases, the inhibitory actions of adenosine were mediated via activation of the A(1)- and not the A(2A)-receptor subtype. Quantitative polymerase chain reaction (qPCR) and immunohistochemical experiments revealed an upregulation of the adenosine A(1) mRNA and an increase in A(1)-receptor staining in TLE neurons compared to control. SIGNIFICANCE Our data indicate that the actions of adenosine on mEC layer II stellate neurons is accentuated in TLE due to an upregulation of adenosine A(1)-receptors. Because adenosine levels are thought to rise during seizure activity, activation of adenosine A(1)-receptors could provide a possible endogenous mechanism to suppress seizure activity and spread within the temporal lobe.
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Affiliation(s)
- Nicholas J Hargus
- Department of Anesthesiology, University of Virginia Health System, Charlottesville, Virginia 22908-0710, USA
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30
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Xia JX, Xiong JX, Wang HK, Duan SM, Ye JN, Hu ZA. Presynaptic inhibition of GABAergic synaptic transmission by adenosine in mouse hypothalamic hypocretin neurons. Neuroscience 2011; 201:46-56. [PMID: 22119641 DOI: 10.1016/j.neuroscience.2011.11.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 11/08/2011] [Accepted: 11/08/2011] [Indexed: 10/15/2022]
Abstract
Hypocretin neurons in the lateral hypothalamus, a new wakefulness-promoting center, have been recently regarded as an important target involved in endogenous adenosine-regulating sleep homeostasis. The GABAergic synaptic transmissions are the main inhibitory afferents to hypocretin neurons, which play an important role in the regulation of excitability of these neurons. The inhibitory effect of adenosine, a homeostatic sleep-promoting factor, on the excitatory glutamatergic synaptic transmissions in hypocretin neurons has been well documented, whether adenosine also modulates these inhibitory GABAergic synaptic transmissions in these neurons has not been investigated. In this study, the effect of adenosine on inhibitory postsynaptic currents (IPSCs) in hypocretin neurons was examined by using perforated patch-clamp recordings in the acute hypothalamic slices. The findings demonstrated that adenosine suppressed the amplitude of evoked IPSCs in a dose-dependent manner, which was completely abolished by 8-cyclopentyltheophylline (CPT), a selective antagonist of adenosine A1 receptor but not adenosine A2 receptor antagonist 3,7-dimethyl-1-(2-propynyl) xanthine. A presynaptic origin was suggested as following: adenosine increased paired-pulse ratio as well as reduced GABAergic miniature IPSC frequency without affecting the miniature IPSC amplitude. Further findings demonstrated that when the frequency of electrical stimulation was raised to 10 Hz, but not 1 Hz, a time-dependent depression of evoked IPSC amplitude was detected in hypocretin neurons, which could be partially blocked by CPT. However, under a higher frequency at 100 Hz stimulation, CPT had no action on the depressed GABAergic synaptic transmission induced by such tetanic stimulation in these hypocretin neurons. These results suggest that endogenous adenosine generated under certain stronger activities of synaptic transmissions exerts an inhibitory effect on GABAergic synaptic transmission in hypocretin neurons by activation of presynaptic adenosine A1 receptors, which may finely regulate the excitability of these neurons as well as eventually modulate the sleep-wakefulness.
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Affiliation(s)
- J X Xia
- Department of Physiology, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, China
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