1
|
Fatt MP, Zhang MD, Kupari J, Altınkök M, Yang Y, Hu Y, Svenningsson P, Ernfors P. Morphine-responsive neurons that regulate mechanical antinociception. Science 2024; 385:eado6593. [PMID: 39208104 PMCID: PMC7616448 DOI: 10.1126/science.ado6593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 07/03/2024] [Indexed: 09/04/2024]
Abstract
Opioids are widely used, effective analgesics to manage severe acute and chronic pain, although they have recently come under scrutiny because of epidemic levels of abuse. While these compounds act on numerous central and peripheral pain pathways, the neuroanatomical substrate for opioid analgesia is not fully understood. By means of single-cell transcriptomics and manipulation of morphine-responsive neurons, we have identified an ensemble of neurons in the rostral ventromedial medulla (RVM) that regulates mechanical nociception in mice. Among these, forced activation or silencing of excitatory RVMBDNF projection neurons mimicked or completely reversed morphine-induced mechanical antinociception, respectively, via a brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB)-dependent mechanism and activation of inhibitory spinal galanin-positive neurons. Our results reveal a specific RVM-spinal circuit that scales mechanical nociception whose function confers the antinociceptive properties of morphine.
Collapse
Affiliation(s)
- Michael P Fatt
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Ming-Dong Zhang
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Jussi Kupari
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Müge Altınkök
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Yunting Yang
- Division of Neuro, Department of Clinical Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Yizhou Hu
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 65 Stockholm, Sweden
| | - Per Svenningsson
- Division of Neuro, Department of Clinical Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Patrik Ernfors
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 65 Stockholm, Sweden
| |
Collapse
|
2
|
Avila C, Sarter M. Cortico-striatal action control inherent of opponent cognitive-motivational styles. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.12.584623. [PMID: 38559086 PMCID: PMC10979997 DOI: 10.1101/2024.03.12.584623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Turning on cue or stopping at a red light requires the detection of such cues to select action sequences, or suppress action, in accordance with cue-associated action rules. Cortico-striatal projections are an essential part of the brain's attention-motor interface. Glutamate-sensing microelectrode arrays were used to measure glutamate transients in the dorsomedial striatum (DMS) of male and female rats walking a treadmill and executing cued turns and stops. Prelimbic-DMS projections were chemogenetically inhibited to determine their behavioral necessity and the cortico-striatal origin of cue-evoked glutamate transients. Furthermore, we investigated rats exhibiting preferably goal-directed (goal trackers, GTs) versus cue-driven attention (sign trackers, STs), to determine the impact of such cognitive-motivational biases on cortico-striatal control. GTs executed more cued turns and initiated such turns more slowly than STs. During turns, but not missed turns or cued stops, cue-evoked glutamate concentrations were higher in GTs than in STs. In conjunction with turn cue-evoked glutamate spike levels, the presence of a single spike rendered GTs to be almost twice as likely to turn than STs. In contrast, multiple glutamate spikes predicted GTs to be less likely to turn than STs. In GTs, but not STs, inhibition of prelimbic-DMS projections attenuated turn rates, turn cue-evoked glutamate peaks, and increased the number of spikes. These findings suggest that turn cue-evoked glutamate release in GTs is tightly controlled by cortico-striatal neuronal activity. In contrast, in STs, glutamate release from DMS glutamatergic terminals may be regulated by other striatal circuitry, preferably mediating cued suppression of action and reward tracking.
Collapse
Affiliation(s)
- Cassandra Avila
- Department of Psychology, University of Michigan, Ann Arbor, MI, USA
| | - Martin Sarter
- Department of Psychology, University of Michigan, Ann Arbor, MI, USA
- Department of Psychology & Neuroscience Program, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
3
|
Xu X, Zuo Y, Chen S, Hatami A, Gu H. Advancements in Brain Research: The In Vivo/In Vitro Electrochemical Detection of Neurochemicals. BIOSENSORS 2024; 14:125. [PMID: 38534232 DOI: 10.3390/bios14030125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/12/2024] [Accepted: 02/20/2024] [Indexed: 03/28/2024]
Abstract
Neurochemicals, crucial for nervous system function, influence vital bodily processes and their fluctuations are linked to neurodegenerative diseases and mental health conditions. Monitoring these compounds is pivotal, yet the intricate nature of the central nervous system poses challenges. Researchers have devised methods, notably electrochemical sensing with micro-nanoscale electrodes, offering high-resolution monitoring despite low concentrations and rapid changes. Implantable sensors enable precise detection in brain tissues with minimal damage, while microdialysis-coupled platforms allow in vivo sampling and subsequent in vitro analysis, addressing the selectivity issues seen in other methods. While lacking temporal resolution, techniques like HPLC and CE complement electrochemical sensing's selectivity, particularly for structurally similar neurochemicals. This review covers essential neurochemicals and explores miniaturized electrochemical sensors for brain analysis, emphasizing microdialysis integration. It discusses the pros and cons of these techniques, forecasting electrochemical sensing's future in neuroscience research. Overall, this comprehensive review outlines the evolution, strengths, and potential applications of electrochemical sensing in the study of neurochemicals, offering insights into future advancements in the field.
Collapse
Affiliation(s)
- Xiaoxuan Xu
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Yimei Zuo
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Shu Chen
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Amir Hatami
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Prof. Sobouti Boulevard, P.O. Box 45195-1159, Zanjan 45137-66731, Iran
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Hui Gu
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30 Gothenburg, Sweden
| |
Collapse
|
4
|
Yu SP, Jiang MQ, Shim SS, Pourkhodadad S, Wei L. Extrasynaptic NMDA receptors in acute and chronic excitotoxicity: implications for preventive treatments of ischemic stroke and late-onset Alzheimer's disease. Mol Neurodegener 2023; 18:43. [PMID: 37400870 DOI: 10.1186/s13024-023-00636-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 06/01/2023] [Indexed: 07/05/2023] Open
Abstract
Stroke and late-onset Alzheimer's disease (AD) are risk factors for each other; the comorbidity of these brain disorders in aging individuals represents a significant challenge in basic research and clinical practice. The similarities and differences between stroke and AD in terms of pathogenesis and pathophysiology, however, have rarely been comparably reviewed. Here, we discuss the research background and recent progresses that are important and informative for the comorbidity of stroke and late-onset AD and related dementia (ADRD). Glutamatergic NMDA receptor (NMDAR) activity and NMDAR-mediated Ca2+ influx are essential for neuronal function and cell survival. An ischemic insult, however, can cause rapid increases in glutamate concentration and excessive activation of NMDARs, leading to swift Ca2+ overload in neuronal cells and acute excitotoxicity within hours and days. On the other hand, mild upregulation of NMDAR activity, commonly seen in AD animal models and patients, is not immediately cytotoxic. Sustained NMDAR hyperactivity and Ca2+ dysregulation lasting from months to years, nevertheless, can be pathogenic for slowly evolving events, i.e. degenerative excitotoxicity, in the development of AD/ADRD. Specifically, Ca2+ influx mediated by extrasynaptic NMDARs (eNMDARs) and a downstream pathway mediated by transient receptor potential cation channel subfamily M member (TRPM) are primarily responsible for excitotoxicity. On the other hand, the NMDAR subunit GluN3A plays a "gatekeeper" role in NMDAR activity and a neuroprotective role against both acute and chronic excitotoxicity. Thus, ischemic stroke and AD share an NMDAR- and Ca2+-mediated pathogenic mechanism that provides a common receptor target for preventive and possibly disease-modifying therapies. Memantine (MEM) preferentially blocks eNMDARs and was approved by the Federal Drug Administration (FDA) for symptomatic treatment of moderate-to-severe AD with variable efficacy. According to the pathogenic role of eNMDARs, it is conceivable that MEM and other eNMDAR antagonists should be administered much earlier, preferably during the presymptomatic phases of AD/ADRD. This anti-AD treatment could simultaneously serve as a preconditioning strategy against stroke that attacks ≥ 50% of AD patients. Future research on the regulation of NMDARs, enduring control of eNMDARs, Ca2+ homeostasis, and downstream events will provide a promising opportunity to understand and treat the comorbidity of AD/ADRD and stroke.
Collapse
Affiliation(s)
- Shan P Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, 30322, USA.
- Center for Visual & Neurocognitive Rehabilitation, Atlanta VA Medical Center, Decatur, GA, 30033, USA.
| | - Michael Q Jiang
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, 30322, USA
- Center for Visual & Neurocognitive Rehabilitation, Atlanta VA Medical Center, Decatur, GA, 30033, USA
| | - Seong S Shim
- Center for Visual & Neurocognitive Rehabilitation, Atlanta VA Medical Center, Decatur, GA, 30033, USA
| | - Soheila Pourkhodadad
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, 30322, USA
- Center for Visual & Neurocognitive Rehabilitation, Atlanta VA Medical Center, Decatur, GA, 30033, USA
| | - Ling Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| |
Collapse
|
5
|
Song Q, Li Q, Yan J, Song Y. Echem methods and electrode types of the current in vivo electrochemical sensing. RSC Adv 2022; 12:17715-17739. [PMID: 35765338 PMCID: PMC9199085 DOI: 10.1039/d2ra01273a] [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: 02/25/2022] [Accepted: 06/02/2022] [Indexed: 11/21/2022] Open
Abstract
For a long time, people have been eager to realize continuous real-time online monitoring of biological compounds. Fortunately, in vivo electrochemical biosensor technology has greatly promoted the development of biological compound detection. This article summarizes the existing in vivo electrochemical detection technologies into two categories: microdialysis (MD) and microelectrode (ME). Then we summarized and discussed the electrode surface time, pollution resistance, linearity and the number of instances of simultaneous detection and analysis, the composition and characteristics of the sensor, and finally, we also predicted and prospected the development of electrochemical technology and sensors in vivo.
Collapse
Affiliation(s)
- Qiuye Song
- The Affiliated Zhangjiagang Hospital of Soochow University Zhangjiagang 215600 Jiangsu People's Republic of China +86 791 87802135 +86 791 87802135
| | - Qianmin Li
- Key Laboratory of Depression Animal Model Based on TCM Syndrome, Jiangxi Administration of Traditional Chinese Medicine, Key Laboratory of TCM for Prevention and Treatment of Brain Diseases with Cognitive Dysfunction, Jiangxi Province, Jiangxi University of Chinese Medicine 1688 Meiling Road Nanchang 330006 China
| | - Jiadong Yan
- The Affiliated Zhangjiagang Hospital of Soochow University Zhangjiagang 215600 Jiangsu People's Republic of China +86 791 87802135 +86 791 87802135
| | - Yonggui Song
- Key Laboratory of Depression Animal Model Based on TCM Syndrome, Jiangxi Administration of Traditional Chinese Medicine, Key Laboratory of TCM for Prevention and Treatment of Brain Diseases with Cognitive Dysfunction, Jiangxi Province, Jiangxi University of Chinese Medicine 1688 Meiling Road Nanchang 330006 China.,Key Laboratory of Pharmacodynamics and Safety Evaluation, Health Commission of Jiangxi Province, Nanchang Medical College 1688 Meiling Road Nanchang 330006 China
| |
Collapse
|
6
|
Li F, Zhou SN, Zeng X, Li Z, Yang R, Wang XX, Meng B, Pei WL, Lu L. Activation of the TREK-1 Potassium Channel Improved Cognitive Deficits in a Mouse Model of Alzheimer's Disease by Modulating Glutamate Metabolism. Mol Neurobiol 2022; 59:5193-5206. [PMID: 35678977 DOI: 10.1007/s12035-022-02776-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 02/10/2022] [Indexed: 10/18/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cognitive dysfunction. The glutamate (Glu) metabolic pathway may be a major contributor to the memory dysfunction associated with AD. The TWIK-related potassium channel-1 (TREK-1) protects against brain ischemia, but any specific role for the channel in AD remains unknown. In this study, we used SAMP8 mice as an AD model and age-matched SAMR1 mice as controls. We explored the trends of changes in TREK-1 channel activity and the levels of AD-related molecules in the brains of SAMP8 mice. We found that the expression level of TREK-1 increased before 3 months of age and then began to decline. The levels of Tau and Glu increased with age whereas the acetylcholine level decreased with age. α-Linolenic acid (ALA), an activator of the TREK-1 channel, significantly increased the TREK-1 level, and improved the learning and memory deficits of SAMP8 mice aged 6 months. The mechanism in play may involve the Glu metabolic pathway. After activation of the TREK-1 channel, damaged neurons and astrocytes were rescued, the levels of Glu and the N-methyl-D-aspartate receptor were downregulated, and the level of glutamate transporter-1 was upregulated. These findings suggest that TREK-1 plays a crucial role in the pathological progression of AD; activation of the TREK-1 channel improved cognitive deficits in SAMP8 mice via a mechanism that involved Glu metabolism. The TREK-1 potassium channel may thus be a valuable therapeutic target in AD patients.
Collapse
Affiliation(s)
- Fang Li
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 73000, Gansu, China
| | - Shu-Ning Zhou
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 73000, Gansu, China.,The College of Traditional Chinese Medicine, Zhejiang Pharmaceutical College, Ningbo, 315000, Zhejiang, China
| | - Xin Zeng
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 73000, Gansu, China
| | - Zhen Li
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 73000, Gansu, China
| | - Rui Yang
- The Endocrinology Department, Lanzhou Hospital of Traditional Chinese Medicine, Lanzhou, 73000, Gansu, China.
| | - Xue-Xi Wang
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 73000, Gansu, China
| | - Bin Meng
- The Second Clinical Medical College, Lanzhou University, Lanzhou, 73000, Gansu, China
| | - Wei-Lin Pei
- The Second Clinical Medical College, Lanzhou University, Lanzhou, 73000, Gansu, China
| | - Li Lu
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 73000, Gansu, China.
| |
Collapse
|
7
|
Regiart M, Ledo A, Fernandes E, Messina GA, Brett CMA, Bertotti M, Barbosa RM. Highly sensitive and selective nanostructured microbiosensors for glucose and lactate simultaneous measurements in blood serum and in vivo in brain tissue. Biosens Bioelectron 2021; 199:113874. [PMID: 34920228 DOI: 10.1016/j.bios.2021.113874] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 02/06/2023]
Abstract
Highly sensitive and selective nanostructured lactate and glucose microbiosensors for their in vivo simultaneous determination in rat brain were developed based on carbon fiber microelectrodes (CFM) modified with nanoporous gold (NPG) using the Dynamic Hydrogen Bubble Template (DHBT) method. Electrodeposition of platinum nanoparticles (PtNP) onto the NPG film enhances the sensitivity and the electrocatalytic properties towards H2O2 detection. The nanostructured microelectrode platform was modified by glucose oxidase (GOx) and lactate oxidase (LOx) enzyme immobilization. High selective measurements were achieved by covering with a perm-selective layer of electropolymerized m-phenylenediamine, deposition of a Nafion® film and by using a null sensor. The morphological characteristics and electroanalytical performance of the microbiosensors were assessed, by scanning electron microscopy and electrochemical techniques, respectively. The PtNP/NPG/CFM shows a high sensitivity to H2O2 (5.96 A M-1 cm-2) at 0.36 V vs. Ag/AgCl, with a linear range from 0.2 to 200 μM, and an LOD of 10 nM. The microbiosensors were applied to the simultaneous determination of lactate and glucose in blood serum samples. Moreover, the basal extracellular concentrations of lactate and glucose were measured in vivo in four different rat brain structures. These results support the potential of the microbiosensor to be used as a valuable tool to investigate brain neurochemicals in vivo.
Collapse
Affiliation(s)
- Matias Regiart
- University of Coimbra, Faculty of Pharmacy, Azinhaga de Santa Comba, 3000-548, Coimbra, Portugal; Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes 748, 05508-000, São Paulo, SP, Brazil
| | - Ana Ledo
- University of Coimbra, Faculty of Pharmacy, Azinhaga de Santa Comba, 3000-548, Coimbra, Portugal; Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal
| | - Eliana Fernandes
- University of Coimbra, Faculty of Pharmacy, Azinhaga de Santa Comba, 3000-548, Coimbra, Portugal
| | - German A Messina
- INQUISAL. Departamento de Química, Universidad Nacional de San Luis. CONICET, Chacabuco 917, D5700BWS, San Luis, Argentina
| | - Christopher M A Brett
- University of Coimbra, Department of Chemistry, CEMMPRE, Faculty of Sciences and Technology, 3004-535 Coimbra, Portugal
| | - Mauro Bertotti
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes 748, 05508-000, São Paulo, SP, Brazil
| | - Rui M Barbosa
- University of Coimbra, Faculty of Pharmacy, Azinhaga de Santa Comba, 3000-548, Coimbra, Portugal; Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga, 3004-504, Coimbra, Portugal.
| |
Collapse
|
8
|
Abstract
The detection of neurotransmitter release from reprogrammed human cell is an important demonstration of their functionality. Electrochemistry has the distinct advantages over alternative methods that it allows for the measuring of the analyte of interest at a high temporal resolution. This is necessary for fast events, such as neurotransmitter release and reuptake, which happen in the order of milliseconds to seconds. The precise description of these kinetic events can lead to insights into the function of cells in health and disease and allows for the exploration of events that might be missed using methods that look at absolute concentration values or methods that have a slower sampling rate. In the present chapter, we describe the use of constant potential amperometry and enzyme-coated multielectrode arrays for the detection of glutamate in vitro. These biosensors have the distinct advantage of "self-referencing," a method providing high selectivity while retaining outstanding temporal resolution. Here, we provide a step-by-step user guide for a commercially available system and its application for in vitro systems such as reprogrammed cells.
Collapse
|
9
|
Intracortical Microelectrode Array Unit Yield under Chronic Conditions: A Comparative Evaluation. MICROMACHINES 2021; 12:mi12080972. [PMID: 34442594 PMCID: PMC8400387 DOI: 10.3390/mi12080972] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/10/2021] [Accepted: 08/12/2021] [Indexed: 01/01/2023]
Abstract
While microelectrode arrays (MEAs) offer the promise of elucidating functional neural circuitry and serve as the basis for a cortical neuroprosthesis, the challenge of designing and demonstrating chronically reliable technology remains. Numerous studies report “chronic” data but the actual time spans and performance measures corresponding to the experimental work vary. In this study, we reviewed the experimental durations that constitute chronic studies across a range of MEA types and animal species to gain an understanding of the widespread variability in reported study duration. For rodents, which are the most commonly used animal model in chronic studies, we examined active electrode yield (AEY) for different array types as a means to contextualize the study duration variance, as well as investigate and interpret the performance of custom devices in comparison to conventional MEAs. We observed wide-spread variance within species for the chronic implantation period and an AEY that decayed linearly in rodent models that implanted commercially-available devices. These observations provide a benchmark for comparing the performance of new technologies and highlight the need for consistency in chronic MEA studies. Additionally, to fully derive performance under chronic conditions, the duration of abiotic failure modes, biological processes induced by indwelling probes, and intended application of the device are key determinants.
Collapse
|
10
|
Mantas I, Vallianatou T, Yang Y, Shariatgorji M, Kalomoiri M, Fridjonsdottir E, Millan MJ, Zhang X, Andrén PE, Svenningsson P. TAAR1-Dependent and -Independent Actions of Tyramine in Interaction With Glutamate Underlie Central Effects of Monoamine Oxidase Inhibition. Biol Psychiatry 2021; 90:16-27. [PMID: 33579534 DOI: 10.1016/j.biopsych.2020.12.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 12/07/2020] [Accepted: 12/11/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Monoamine oxidase inhibitors (MAOIs) exert therapeutic actions by elevating extracellular levels of monoamines in the brain. Irreversible MAOIs cause serious hypertensive crises owing to peripheral accumulation of tyramine, but the role of tyramine in the central effects of MAOIs remains elusive, an issue addressed herein. To achieve robust inhibition of MAOA/B, the clinically used antidepressant tranylcypromine (TCP) was employed. METHODS Behavioral, histological, mass spectrometry imaging, and biosensor-mediated measures of glutamate were conducted with MAOIs in wild-type and TAAR1-knockout (KO) mice. RESULTS Both antidepressant and locomotion responses to TCP were enhanced in TAAR1-KO mice. A recently developed fluoromethylpyridinium-based mass spectrometry imaging method revealed robust accumulation of striatal tyramine on TCP administration. Furthermore, tyramine accumulation was higher in TAAR1-KO versus wild-type mice, suggesting a negative feedback mechanism for TAAR1 in sensing tyramine levels. Combined histoenzymological and immunohistological studies revealed hitherto unknown TAAR1 localization in brain areas projecting to the substantia nigra/ventral tegmental area. Using an enzyme-based biosensor technology, we found that both TCP and tyramine reduced glutamate release in the substantia nigra in wild-type but not in TAAR1-KO mice. Moreover, glutamate measures in freely moving animals treated with TCP demonstrated that TAAR1 prevents glutamate accumulation in the substantia nigra during hyperlocomotive states. CONCLUSIONS These observations suggest that tyramine, in interaction with glutamate, is involved in centrally mediated behavioral, transcriptional, and neurochemical effects of MAOIs.
Collapse
Affiliation(s)
- Ioannis Mantas
- Department of Neurology and Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| | - Theodosia Vallianatou
- Department of Pharmaceutical Biosciences, Medical Mass Spectrometry Imaging, Uppsala University, Uppsala, Sweden
| | - Yunting Yang
- Department of Neurology and Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Mohammadreza Shariatgorji
- Department of Pharmaceutical Biosciences, Medical Mass Spectrometry Imaging, Uppsala University, Uppsala, Sweden; National Resource for Mass Spectrometry Imaging, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Maria Kalomoiri
- Department of Neurology and Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Elva Fridjonsdottir
- Department of Pharmaceutical Biosciences, Medical Mass Spectrometry Imaging, Uppsala University, Uppsala, Sweden
| | - Mark J Millan
- Centre for Therapeutic Innovation-CNS, Institut de Recherches Servier, Centre de Recherches de Croissy, Paris, France
| | - Xiaoqun Zhang
- Department of Neurology and Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Per E Andrén
- Department of Pharmaceutical Biosciences, Medical Mass Spectrometry Imaging, Uppsala University, Uppsala, Sweden; National Resource for Mass Spectrometry Imaging, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Per Svenningsson
- Department of Neurology and Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
11
|
Sarter M, Avila C, Kucinski A, Donovan E. Make a Left Turn: Cortico-Striatal Circuitry Mediating the Attentional Control of Complex Movements. Mov Disord 2021; 36:535-546. [PMID: 33615556 DOI: 10.1002/mds.28532] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND In movement disorders such as Parkinson's disease (PD), cholinergic signaling is disrupted by the loss of basal forebrain cholinergic neurons, as well as aberrant activity in striatal cholinergic interneurons (ChIs). Several lines of evidence suggest that gait imbalance, a key disabling symptom of PD, may be driven by alterations in high-level frontal cortical and cortico-striatal processing more typically associated with cognitive dysfunction. METHODS Here we describe the corticostriatal circuitry that mediates the cognitive-motor interactions underlying such complex movement control. The ability to navigate dynamic, obstacle-rich environments requires the continuous integration of information about the environment with movement selection and sequencing. The cortical-attentional processing of extero- and interoceptive cues requires modulation by cholinergic activity to guide striatal movement control. Cue-derived information is "transferred" to striatal circuitry primarily via fronto-striatal glutamatergic projections. RESULT Evidence from parkinsonian fallers and from a rodent model reproducing the dual cholinergic-dopaminergic losses observed in these patients supports the main hypotheses derived from this neuronal circuitry-guided conceptualization of parkinsonian falls. Furthermore, in the striatum, ChIs constitute a particularly critical node for the integration of cortical with midbrain dopaminergic afferents and thus for cues to control movements. CONCLUSION Procholinergic treatments that enhance or rescue cortical and striatal mechanisms may improve complex movement control in parkinsonian fallers and perhaps also in older persons suffering from gait disorders and a propensity for falls. © 2021 International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Martin Sarter
- Department of Psychology & Neuroscience Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Cassandra Avila
- Department of Psychology & Neuroscience Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Aaron Kucinski
- Department of Psychology & Neuroscience Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Eryn Donovan
- Department of Psychology & Neuroscience Program, University of Michigan, Ann Arbor, Michigan, USA
| |
Collapse
|
12
|
Plotegher N, Filadi R, Pizzo P, Duchen MR. Excitotoxicity Revisited: Mitochondria on the Verge of a Nervous Breakdown. Trends Neurosci 2021; 44:342-351. [PMID: 33608137 DOI: 10.1016/j.tins.2021.01.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 12/03/2020] [Accepted: 01/08/2021] [Indexed: 12/30/2022]
Abstract
Excitotoxicity is likely to occur in pathological scenarios in which mitochondrial function is already compromised, shaping neuronal responses to glutamate. In fact, mitochondria sustain cell bioenergetics, tune intracellular Ca2+ dynamics, and regulate glutamate availability by using it as metabolic substrate. Here, we suggest the need to explore glutamate toxicity in the context of specific disease models in which it may occur, re-evaluating the impact of mitochondrial dysfunction on glutamate excitotoxicity. Our aim is to signpost new approaches, perhaps combining glutamate and pathways to rescue mitochondrial function, as therapeutic targets in neurological disorders.
Collapse
Affiliation(s)
| | - Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, Padova, Italy; Neuroscience Institute, National Research Council (CNR), Padua, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, Padova, Italy; Neuroscience Institute, National Research Council (CNR), Padua, Italy
| | - Michael R Duchen
- Department of Cell and Developmental Biology, University College London, London, UK.
| |
Collapse
|
13
|
Lazarevic V, Yang Y, Flais I, Svenningsson P. Ketamine decreases neuronally released glutamate via retrograde stimulation of presynaptic adenosine A1 receptors. Mol Psychiatry 2021; 26:7425-7435. [PMID: 34376822 PMCID: PMC8872981 DOI: 10.1038/s41380-021-01246-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 07/09/2021] [Accepted: 07/21/2021] [Indexed: 12/27/2022]
Abstract
Ketamine produces a rapid antidepressant response in patients with major depressive disorder (MDD), but the underlying mechanisms appear multifaceted. One hypothesis, proposes that by antagonizing NMDA receptors on GABAergic interneurons, ketamine disinhibits afferens to glutamatergic principal neurons and increases extracellular glutamate levels. However, ketamine seems also to reduce rapid glutamate release at some synapses. Therefore, clinical studies in MDD patients have stressed the need to identify mechanisms whereby ketamine decreases presynaptic activity and glutamate release. In the present study, the effect of ketamine and its antidepressant metabolite, (2R,6R)-HNK, on neuronally derived glutamate release was examined in rodents. We used FAST methodology to measure depolarization-evoked extracellular glutamate levels in vivo in freely moving or anesthetized animals, synaptosomes to detect synaptic recycling ex vivo and primary cortical neurons to perform functional imaging and to examine intracellular signaling in vitro. In all these versatile approaches, ketamine and (2R,6R)-HNK reduced glutamate release in a manner which could be blocked by AMPA receptor antagonism. Antagonism of adenosine A1 receptors, which are almost exclusively expressed at nerve terminals, also counteracted ketamine's effect on glutamate release and presynaptic activity. Signal transduction studies in primary neuronal cultures demonstrated that ketamine reduced P-T286-CamKII and P-S9-Synapsin, which correlated with decreased synaptic vesicle recycling. Moreover, systemic administration of A1R antagonist counteracted the antidepressant-like actions of ketamine and (2R,6R)-HNK in the forced swim test. To conclude, by studying neuronally released glutamate, we identified a novel retrograde adenosinergic feedback mechanism that mediate inhibitory actions of ketamine on glutamate release that may contribute to its rapid antidepressant action.
Collapse
Affiliation(s)
- Vesna Lazarevic
- grid.4714.60000 0004 1937 0626Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Yunting Yang
- grid.4714.60000 0004 1937 0626Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ivana Flais
- grid.4714.60000 0004 1937 0626Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Per Svenningsson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| |
Collapse
|
14
|
Keighron JD, Wang Y, Cans AS. Electrochemistry of Single-Vesicle Events. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2020; 13:159-181. [PMID: 32151142 DOI: 10.1146/annurev-anchem-061417-010032] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Neuronal transmission relies on electrical signals and the transfer of chemical signals from one neuron to another. Chemical messages are transmitted from presynaptic neurons to neighboring neurons through the triggered fusion of neurotransmitter-filled vesicles with the cell plasma membrane. This process, known as exocytosis, involves the rapid release of neurotransmitter solutions that are detected with high affinity by the postsynaptic neuron. The type and number of neurotransmitters released and the frequency of vesicular events govern brain functions such as cognition, decision making, learning, and memory. Therefore, to understand neurotransmitters and neuronal function, analytical tools capable of quantitative and chemically selective detection of neurotransmitters with high spatiotemporal resolution are needed. Electrochemistry offers powerful techniques that are sufficiently rapid to allow for the detection of exocytosis activity and provides quantitative measurements of vesicle neurotransmitter content and neurotransmitter release from individual vesicle events. In this review, we provide an overview of the most commonly used electrochemical methods for monitoring single-vesicle events, including recent developments and what is needed for future research.
Collapse
Affiliation(s)
- Jacqueline D Keighron
- Department of Chemical and Biological Sciences, New York Institute of Technology, Old Westbury, New York 11568, USA
| | - Yuanmo Wang
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden;
| | - Ann-Sofie Cans
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden;
| |
Collapse
|
15
|
Xiao G, Song Y, Zhang Y, Xing Y, Xu S, Lu Z, Wang M, Cai X. Cellular-Scale Microelectrode Arrays to Monitor Movement-Related Neuron Activities in the Epileptic Hippocampus of Awake Mice. IEEE Trans Biomed Eng 2020; 68:19-25. [PMID: 32356734 DOI: 10.1109/tbme.2020.2990356] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Epilepsy affects 50 million people worldwide and its pathogenesis is still unknown. In particular, the movement-related neural activities involving glutamate (Glu) and electrophysiological signals at cellular level remains unclear. METHODS A cellular-scale implantable microelectrode array (MEA) was fabricated to detect the movement-related neural activities involving Glu concentration and electrophysiological signals. Platinum and reduced graphene oxide nanocomposites were deposited to enhance the surface area. Glu oxidase (Gluox) were coated to effectively recognize Glu molecule. RESULTS Neural activities in the hippocampus of normal and epileptic mice is different, and the changes are closely connected with movement. Glu concentration and spike firing rate in the epileptic mice were much higher than those in the normal ones. And the neural activities with significant synchronization were detected in the epileptic mice even without seizure occurrence. Meanwhile, the spikes fire more intensively and Glu level became much higher during the movement of the mice compared to the stationary state. CONCLUSION The existing abnormality of neural activities in the epileptic mice are potential factors to induce a seizure. Movement may impact the neural activities and the duration of seizure. SIGNIFICANCE The MEA can monitor changes of movement, Glu and neuron discharges synchronously and provides us an effective technology to understand the neuronal disease.
Collapse
|
16
|
Krishna G, Beitchman JA, Bromberg CE, Currier Thomas T. Approaches to Monitor Circuit Disruption after Traumatic Brain Injury: Frontiers in Preclinical Research. Int J Mol Sci 2020; 21:ijms21020588. [PMID: 31963314 PMCID: PMC7014469 DOI: 10.3390/ijms21020588] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/03/2020] [Accepted: 01/13/2020] [Indexed: 12/19/2022] Open
Abstract
Mild traumatic brain injury (TBI) often results in pathophysiological damage that can manifest as both acute and chronic neurological deficits. In an attempt to repair and reconnect disrupted circuits to compensate for loss of afferent and efferent connections, maladaptive circuitry is created and contributes to neurological deficits, including post-concussive symptoms. The TBI-induced pathology physically and metabolically changes the structure and function of neurons associated with behaviorally relevant circuit function. Complex neurological processing is governed, in part, by circuitry mediated by primary and modulatory neurotransmitter systems, where signaling is disrupted acutely and chronically after injury, and therefore serves as a primary target for treatment. Monitoring of neurotransmitter signaling in experimental models with technology empowered with improved temporal and spatial resolution is capable of recording in vivo extracellular neurotransmitter signaling in behaviorally relevant circuits. Here, we review preclinical evidence in TBI literature that implicates the role of neurotransmitter changes mediating circuit function that contributes to neurological deficits in the post-acute and chronic phases and methods developed for in vivo neurochemical monitoring. Coupling TBI models demonstrating chronic behavioral deficits with in vivo technologies capable of real-time monitoring of neurotransmitters provides an innovative approach to directly quantify and characterize neurotransmitter signaling as a universal consequence of TBI and the direct influence of pharmacological approaches on both behavior and signaling.
Collapse
Affiliation(s)
- Gokul Krishna
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ 85016, USA; (G.K.); (J.A.B.); (C.E.B.)
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
| | - Joshua A. Beitchman
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ 85016, USA; (G.K.); (J.A.B.); (C.E.B.)
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
- College of Graduate Studies, Midwestern University, Glendale, AZ 85308, USA
| | - Caitlin E. Bromberg
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ 85016, USA; (G.K.); (J.A.B.); (C.E.B.)
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
| | - Theresa Currier Thomas
- Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ 85016, USA; (G.K.); (J.A.B.); (C.E.B.)
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, USA
- Phoenix VA Healthcare System, Phoenix, AZ 85012, USA
- Correspondence: ; Tel.: +1-602-827-2348
| |
Collapse
|
17
|
Abstract
In vivo electrochemical sensing based on implantable microelectrodes is a strong driving force of analytical neurochemistry in brain. The complex and dynamic neurochemical network sets stringent standards of in vivo electrochemical sensors including high spatiotemporal resolution, selectivity, sensitivity, and minimized disturbance on brain function. Although advanced materials and novel technologies have promoted the development of in vivo electrochemical sensors drastically, gaps with the goals still exist. This Review mainly focuses on recent attempts on the key issues of in vivo electrochemical sensors including selectivity, tissue response and sensing reliability, and compatibility with electrophysiological techniques. In vivo electrochemical methods with bare carbon fiber electrodes, of which the selectivity is achieved either with electrochemical techniques such as fast-scan cyclic voltammetry and differential pulse voltammetry or based on the physiological nature will not be reviewed. Following the elaboration of each issue involved in in vivo electrochemical sensors, possible solutions supported by the latest methodological progress will be discussed, aiming to provide inspiring and practical instructions for future research.
Collapse
Affiliation(s)
- Cong Xu
- Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fei Wu
- Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ping Yu
- Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lanqun Mao
- Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
18
|
Mantas I, Yang Y, Mannoury-la-Cour C, Millan MJ, Zhang X, Svenningsson P. Genetic deletion of GPR88 enhances the locomotor response to L-DOPA in experimental parkinsonism while counteracting the induction of dyskinesia. Neuropharmacology 2019; 162:107829. [PMID: 31666199 DOI: 10.1016/j.neuropharm.2019.107829] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 11/27/2022]
Abstract
Parkinson's disease (PD) is characterized by progressive loss of midbrain dopaminergic neurons and treated with the dopamine precursor, 3,4-dihydroxy-l-phenylalanine (L-DOPA). Prolonged L-DOPA treatment is however associated with waning efficacy and the induction of L-DOPA induced dyskinesia (LID). GPR88 is an orphan G-protein Coupled Receptor (GPCR) expressed in dopaminoceptive striatal medium spiny neurons (MSNs) and their afferent corticostriatal glutamatergic neurons. Here, we studied the role of GPR88 in experimental parkinsonism and LID. Chronic L-DOPA administration to male GPR88 KO mice, subjected to unilateral 6-hydroxydopamine (6-OHDA) lesions of the medial forebrain bundle, resulted in more rotations than in their WT counterparts. Conversely, GPR88 KO mice had a lower abnormal involuntary movements (AIMs) score. These behavioral responses were accompanied by altered transcription of L-DOPA upregulated genes in lesioned GPR88 KO compared to WT striata. In accordance with a role for serotonin neurons in LID development, WT but not GPR88 KO striata exhibited 5-hydroxytryptamine displacement upon repeated L-DOPA treatment. Intact male GPR88 KO mice showed diminished tacrine-induced PD-like tremor and spontaneous hyperlocomotion. Dopamine and its metabolites were not increased in male GPR88 KO mice, but biosensor recordings revealed increased spontaneous/basal and evoked glutamate release in striata of male GPR88 KO mice. In conclusion, genetic deletion of GPR88 promotes l-DOPA-induced rotation and spontaneous locomotion yet suppresses the induction of LIDs and also reduces tremor. These data provide behavioral, neurochemical and molecular support that GPR88 antagonism may favour motor relief in PD patients without aggravating the induction of motor side effects.
Collapse
Affiliation(s)
- Ioannis Mantas
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| | - Yunting Yang
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Clotilde Mannoury-la-Cour
- Centre for Therapeutic Innovation-CNS, Institut de Recherches Servier, Centre de Recherches de Croissy, Paris, France
| | - Mark J Millan
- Centre for Therapeutic Innovation-CNS, Institut de Recherches Servier, Centre de Recherches de Croissy, Paris, France
| | - Xiaoqun Zhang
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Per Svenningsson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| |
Collapse
|
19
|
van den Brink FTG, Phisonkunkasem T, Asthana A, Bomer JG, van den Maagdenberg AMJM, Tolner EA, Odijk M. A miniaturized push-pull-perfusion probe for few-second sampling of neurotransmitters in the mouse brain. LAB ON A CHIP 2019; 19:1332-1343. [PMID: 30869670 DOI: 10.1039/c8lc01137k] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Measuring biomolecule concentrations in the brain of living animals, in real time, is a challenging task, especially when detailed information at high temporal resolution is also required. Traditionally, microdialysis probes are used that generally have sampling areas in the order of about 1 mm2, and provide information on concentrations with a temporal resolution of at least several minutes. In this paper, we present a novel miniaturized push-pull perfusion sampling probe that uses an array of small 3 μm-wide sampling channels to sample neurotransmitters at a typical recovery rate of 61%, with a reduced risk of clogging. The added feature to segment the dialysate inside the probe into small water-in-decane droplets enables the detection of concentrations with a temporal resolution of a few seconds. Here we used the probe for in vivo recordings of neurotransmitter glutamate released upon electrical stimulation in the brain of a mouse to demonstrate the feasibility of the probe for real-time neurochemical brain analysis.
Collapse
Affiliation(s)
- Floris T G van den Brink
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
| | - Thas Phisonkunkasem
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Ashish Asthana
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
| | - Johan G Bomer
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
| | - Arn M J M van den Maagdenberg
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands and Department of Neurology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Else A Tolner
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands and Department of Neurology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Mathieu Odijk
- BIOS - Microdevices for Chemical Analysis group, MESA+ Institute for Nanotechnology, Techmed Centre, University of Twente, Hallenweg 15, 7522 NH Enschede, The Netherlands.
| |
Collapse
|
20
|
Ganesana M, Trikantzopoulos E, Maniar Y, Lee ST, Venton BJ. Development of a novel micro biosensor for in vivo monitoring of glutamate release in the brain. Biosens Bioelectron 2019; 130:103-109. [PMID: 30731343 DOI: 10.1016/j.bios.2019.01.049] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/09/2019] [Accepted: 01/20/2019] [Indexed: 11/16/2022]
Abstract
L- Glutamate is the main excitatory neurotransmitter in the central nervous system and hyperglutamatergic signaling is implicated in neurological and neurodegenerative diseases. Monitoring glutamate with a glutamate oxidase-based amperometric biosensor offers advantages such as high spatial and high temporal resolution. However, commercially-available glutamate biosensors are expensive and larger in size. Here, we report the development of 50 µm diameter biosensor for real-time monitoring of L-glutamate in vivo. A polymer, poly-o-phenylenediamine (PPD) layer was electropolymerized onto a 50 µm Pt wire to act as a permselective membrane. Then, glutamate oxidase entrapped in a biocompatible chitosan matrix was cast onto the microelectrode surface. Finally, ascorbate oxidase was coated to eliminate interferences from high levels of extracellular ascorbic acid present in brain tissue. L-glutamate measurements were performed amperometrically at an applied potential of 0.6 V vs Ag/AgCl. The biosensor exhibited a linear range from 5 to 150 μM, with a high sensitivity of 0.097 ± 0.001 nA/μM and one-week storage stability. The biosensor also showed a rapid steady state response to L-glutamate within 2 s, with a limit of detection of 0.044 μM. The biosensor was used successfully to detect stimulated glutamate in the subthalamic nucleus in brain slices and in vivo. Thus, this biosensor is appropriate for future neuroscience applications.
Collapse
Affiliation(s)
- Mallikarjunarao Ganesana
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - Elefterios Trikantzopoulos
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - Yash Maniar
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - Scott T Lee
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - B Jill Venton
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA.
| |
Collapse
|
21
|
Hascup ER, Broderick SO, Russell MK, Fang Y, Bartke A, Boger HA, Hascup KN. Diet-induced insulin resistance elevates hippocampal glutamate as well as VGLUT1 and GFAP expression in AβPP/PS1 mice. J Neurochem 2019; 148:219-237. [PMID: 30472734 DOI: 10.1111/jnc.14634] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 10/31/2018] [Accepted: 11/13/2018] [Indexed: 12/21/2022]
Abstract
The symptomologies of Alzheimer's disease (AD) develop over decades suggesting modifiable lifestyle factors may contribute to disease pathogenesis. In humans, hyperinsulinemia associated with type 2 diabetes mellitus increases the risk for developing AD and both diseases share similar age-related etiologies including amyloidogenesis. Since we have demonstrated that soluble Aβ42 elicits glutamate release, we wanted to understand how diet-induced insulin resistance alters hippocampal glutamate dynamics, which are important for memory formation and consolidation. Eight to twelve-week-old C57BL/6J and AβPP/PS1 mice were placed on either a low-fat diet or high-fat diet (HFD) for 8 months. A HFD led to significant weight increases as well as impaired insulin sensitivity, glucose tolerance, and learning in both C57BL/6J and AβPP/PS1 mice. AβPP/PS1 low-fat diet mice had elevated hippocampal basal as well as stimulus-evoked glutamate release that was further increased with consumption of a HFD. Immunohistochemistry indicated an increase in vesicular glutamate transporter 1 and glial fibrillary acidic protein density in hippocampal subregions corresponding with this elevated extracellular glutamate. While no differences in hippocampal plaque load were observed, the elevated astrogliotic response surrounding the plaques in AβPP/PS1 HFD mice may have been a compensatory mechanism to control plaque accumulation. These data support that AβPP/PS1 mice have chronically elevated extracellular glutamate that is exacerbated by a HFD and that modifiable lifestyle factors such as obesity-induced insulin resistance can contribute to AD pathogenesis. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* and for *Open Data* because it made the data publicly available. The data can be accessed at https://osf.io/5whvu (figures for data) and https://osf.io/gd5vf (materials and methods). The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/. Cover Image for this issue: doi: 10.1111/jnc.14490.
Collapse
Affiliation(s)
- Erin R Hascup
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, Illinois, USA.,Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Sarah O Broderick
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, Illinois, USA
| | - Mary K Russell
- Department of Neuroscience, Center on Aging, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Yimin Fang
- Division of Geriatric Research, Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Andrzej Bartke
- Division of Geriatric Research, Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Heather A Boger
- Department of Neuroscience, Center on Aging, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Kevin N Hascup
- Department of Neurology, Center for Alzheimer's Disease and Related Disorders, Neurosciences Institute, Springfield, Illinois, USA
| |
Collapse
|
22
|
Isoaho N, Peltola E, Sainio S, Koskinen J, Laurila T. Pt-grown carbon nanofibers for enzymatic glutamate biosensors and assessment of their biocompatibility. RSC Adv 2018; 8:35802-35812. [PMID: 35547905 PMCID: PMC9088215 DOI: 10.1039/c8ra07766e] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 10/09/2018] [Indexed: 01/11/2023] Open
Abstract
Application-specific carbon nanofibers grown from Pt-catalyst layers have been shown to be a promising material for biosensor development. Here we demonstrate immobilization of glutamate oxidase on them and their use for amperometric detection of glutamate at two different potentials. At -0.15 V vs. Ag/AgCl at concentrations higher than 100 μM the oxygen reduction reaction severely interferes with the enzymatic production of H2O2 and consequently affects the detection of glutamate. On the other hand, at 0.6 V vs. Ag/AgCl enzyme saturation starts to affect the measurement above a glutamate concentration of 100 μM. Moreover, we suggest here that glutamate itself might foul Pt surfaces to some degree, which should be taken into account when designing Pt-based sensors operating at high anodic potentials. Finally, the Pt-grown and Ni-grown carbon nanofibers were shown to be biocompatible. However, the cells on Pt-grown carbon nanofibers had different morphology and formation of filopodia compared to those on Ni-grown carbon nanofibers. The effect was expected to be caused rather by the different fiber dimensions between the samples than the catalyst metal itself. Further experiments are required to find the optimal dimensions of CNFs for biological purposes.
Collapse
Affiliation(s)
- Noora Isoaho
- Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University PO Box 13500 00076 Aalto Finland +358 50 341 4375
| | - Emilia Peltola
- Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University PO Box 13500 00076 Aalto Finland +358 50 341 4375
| | - Sami Sainio
- Department Chemistry and Materials Science, School of Chemical Technology, Aalto University PO Box 16200 00076 Aalto Finland
| | - Jari Koskinen
- Department Chemistry and Materials Science, School of Chemical Technology, Aalto University PO Box 16200 00076 Aalto Finland
| | - Tomi Laurila
- Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University PO Box 13500 00076 Aalto Finland +358 50 341 4375
| |
Collapse
|
23
|
Pál B. Involvement of extrasynaptic glutamate in physiological and pathophysiological changes of neuronal excitability. Cell Mol Life Sci 2018; 75:2917-2949. [PMID: 29766217 PMCID: PMC11105518 DOI: 10.1007/s00018-018-2837-5] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 04/27/2018] [Accepted: 05/07/2018] [Indexed: 12/14/2022]
Abstract
Glutamate is the most abundant neurotransmitter of the central nervous system, as the majority of neurons use glutamate as neurotransmitter. It is also well known that this neurotransmitter is not restricted to synaptic clefts, but found in the extrasynaptic regions as ambient glutamate. Extrasynaptic glutamate originates from spillover of synaptic release, as well as from astrocytes and microglia. Its concentration is magnitudes lower than in the synaptic cleft, but receptors responding to it have higher affinity for it. Extrasynaptic glutamate receptors can be found in neuronal somatodendritic location, on astroglia, oligodendrocytes or microglia. Activation of them leads to changes of neuronal excitability with different amplitude and kinetics. Extrasynaptic glutamate is taken up by neurons and astrocytes mostly via EAAT transporters, and astrocytes, in turn metabolize it to glutamine. Extrasynaptic glutamate is involved in several physiological phenomena of the central nervous system. It regulates neuronal excitability and synaptic strength by involving astroglia; contributing to learning and memory formation, neurosecretory and neuromodulatory mechanisms, as well as sleep homeostasis.The extrasynaptic glutamatergic system is affected in several brain pathologies related to excitotoxicity, neurodegeneration or neuroinflammation. Being present in dementias, neurodegenerative and neuropsychiatric diseases or tumor invasion in a seemingly uniform way, the system possibly provides a common component of their pathogenesis. Although parts of the system are extensively discussed by several recent reviews, in this review I attempt to summarize physiological actions of the extrasynaptic glutamate on neuronal excitability and provide a brief insight to its pathology for basic understanding of the topic.
Collapse
Affiliation(s)
- Balázs Pál
- Department of Physiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, Debrecen, 4012, Hungary.
| |
Collapse
|
24
|
Geyer ED, Shetty PA, Suozzi CJ, Allen DZ, Benavidez PP, Liu J, Hollis CN, Gerhardt GA, Quintero JE, Burmeister JJ, Whitaker EE. Adaptation of Microelectrode Array Technology for the Study of Anesthesia-induced Neurotoxicity in the Intact Piglet Brain. J Vis Exp 2018. [PMID: 29806825 PMCID: PMC6101183 DOI: 10.3791/57391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Every year, millions of children undergo anesthesia for a multitude of procedures. However, studies in both animals and humans have called into question the safety of anesthesia in children, implicating anesthetics as potentially toxic to the brain in development. To date, no studies have successfully elucidated the mechanism(s) by which anesthesia may be neurotoxic. Animal studies allow investigation of such mechanisms, and neonatal piglets represent an excellent model to study these effects due to their striking developmental similarities to the human brain. This protocol adapts the use of enzyme-based microelectrode array (MEA) technology as a novel way to study the mechanism(s) of anesthesia-induced neurotoxicity (AIN). MEAs enable real-time monitoring of in vivo neurotransmitter activity and offer exceptional temporal and spatial resolution. It is hypothesized that anesthetic neurotoxicity is caused in part by glutamate dysregulation and MEAs offer a method to measure glutamate. The novel implementation of MEA technology in a piglet model presents a unique opportunity for the study of AIN.
Collapse
Affiliation(s)
- Emily D Geyer
- Department of Anesthesiology, Ohio State University College of Medicine
| | - Prithvi A Shetty
- Department of Anesthesiology, Ohio State University College of Medicine
| | | | - David Z Allen
- Department of Anesthesiology, Ohio State University College of Medicine; Medical Student Research Program, Ohio State University College of Medicine
| | - Pamela P Benavidez
- Department of Anesthesiology, Ohio State University College of Medicine; Medical Student Research Program, Ohio State University College of Medicine
| | - Joseph Liu
- Department of Anesthesiology, Ohio State University College of Medicine; Department of Anesthesiology and Pain Medicine, Nationwide Children's Hospital
| | - Charles N Hollis
- Department of Anesthesiology, Ohio State University College of Medicine
| | - Greg A Gerhardt
- Department of Neuroscience, University of Kentucky Medical Center
| | - Jorge E Quintero
- Department of Neuroscience, University of Kentucky Medical Center
| | | | - Emmett E Whitaker
- Department of Anesthesiology, Ohio State University College of Medicine; Department of Anesthesiology and Pain Medicine, Nationwide Children's Hospital;
| |
Collapse
|
25
|
Chatard C, Meiller A, Marinesco S. Microelectrode Biosensors forin vivoAnalysis of Brain Interstitial Fluid. ELECTROANAL 2018. [DOI: 10.1002/elan.201700836] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Charles Chatard
- INSERM U1028, CNRS UMR5292; Lyon Neuroscience Research Center, Team TIGER
- Université Claude Bernard Lyon 1; Lyon France
| | - Anne Meiller
- AniRA-Neurochem Technological Platform; Lyon France
- Université Claude Bernard Lyon 1; Lyon France
| | - Stéphane Marinesco
- INSERM U1028, CNRS UMR5292; Lyon Neuroscience Research Center, Team TIGER
- AniRA-Neurochem Technological Platform; Lyon France
- Université Claude Bernard Lyon 1; Lyon France
- Lyon Neuroscience Research Center, Team TIGER; Faculty of Medicine; 8 Avenue Rockefeller 69373 Lyon Cedex 08 France
| |
Collapse
|
26
|
Scofield MD, Heinsbroek JA, Gipson CD, Kupchik YM, Spencer S, Smith ACW, Roberts-Wolfe D, Kalivas PW. The Nucleus Accumbens: Mechanisms of Addiction across Drug Classes Reflect the Importance of Glutamate Homeostasis. Pharmacol Rev 2017; 68:816-71. [PMID: 27363441 DOI: 10.1124/pr.116.012484] [Citation(s) in RCA: 372] [Impact Index Per Article: 53.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The nucleus accumbens is a major input structure of the basal ganglia and integrates information from cortical and limbic structures to mediate goal-directed behaviors. Chronic exposure to several classes of drugs of abuse disrupts plasticity in this region, allowing drug-associated cues to engender a pathologic motivation for drug seeking. A number of alterations in glutamatergic transmission occur within the nucleus accumbens after withdrawal from chronic drug exposure. These drug-induced neuroadaptations serve as the molecular basis for relapse vulnerability. In this review, we focus on the role that glutamate signal transduction in the nucleus accumbens plays in addiction-related behaviors. First, we explore the nucleus accumbens, including the cell types and neuronal populations present as well as afferent and efferent connections. Next we discuss rodent models of addiction and assess the viability of these models for testing candidate pharmacotherapies for the prevention of relapse. Then we provide a review of the literature describing how synaptic plasticity in the accumbens is altered after exposure to drugs of abuse and withdrawal and also how pharmacological manipulation of glutamate systems in the accumbens can inhibit drug seeking in the laboratory setting. Finally, we examine results from clinical trials in which pharmacotherapies designed to manipulate glutamate systems have been effective in treating relapse in human patients. Further elucidation of how drugs of abuse alter glutamatergic plasticity within the accumbens will be necessary for the development of new therapeutics for the treatment of addiction across all classes of addictive substances.
Collapse
Affiliation(s)
- M D Scofield
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| | - J A Heinsbroek
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| | - C D Gipson
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| | - Y M Kupchik
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| | - S Spencer
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| | - A C W Smith
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| | - D Roberts-Wolfe
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| | - P W Kalivas
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina (M.D.S., J.A.H., S.S., D.R.-W., P.W.K.); Department of Psychology, Arizona State University, Tempe, Arizona (C.D.G.); Department of Neuroscience, Hebrew University, Jerusalem, Israel (Y.M.K.); and Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, New York (A.C.W.S.)
| |
Collapse
|
27
|
Li DH, Yang XF. Remote modulation of network excitability during deep brain stimulation for epilepsy. Seizure 2017; 47:42-50. [DOI: 10.1016/j.seizure.2017.02.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 01/20/2017] [Accepted: 02/28/2017] [Indexed: 12/18/2022] Open
|
28
|
Hunsberger HC, Konat GW, Reed MN. Peripheral viral challenge elevates extracellular glutamate in the hippocampus leading to seizure hypersusceptibility. J Neurochem 2017; 141:341-346. [PMID: 28244106 DOI: 10.1111/jnc.13999] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 01/25/2017] [Accepted: 02/21/2017] [Indexed: 12/27/2022]
Abstract
Peripheral viral infections increase seizure propensity and intensity in susceptible individuals. We have modeled this comorbidity by demonstrating that the acute phase response instigated by an intraperitoneal (i.p.) injection of a viral mimetic, polyinosinic-polycytidylic acid (PIC), induces protracted hypersusceptibility to kainic acid-induced seizures. We have further demonstrated that PIC challenge robustly increases the level of tonic extracellular glutamate and neuronal excitability in the hippocampus. This study was undertaken to determine a relationship between tonic glutamate and seizure susceptibility following PIC challenge. Briefly, glutamate-sensing microelectrodes were permanently implanted into the CA1 of 8-week-old female C57BL/6 mice. Following a 3-day recovery, acute phase response was induced by i.p. injection of 12 mg/kg of PIC, while saline-injected mice served as controls. Tonic glutamate was measured at 1, 2, 3 and 4 days after PIC challenge. PIC challenge induced an approximately fourfold increase in tonic glutamate levels measured after 24 h. The levels gradually declined to the baseline values within 4 days. Twenty-four hours after PIC challenge, the mice featured an approximately threefold increase in cumulative seizure scores and twofold increase in the duration of status epilepticus induced by subcutaneous injection of 12 mg/kg of kainic acid. Seizure scores positively correlated with pre-seizure tonic glutamate. Moreover, seizures resulted in a profound (76%) elevation of extracellular glutamate in the CA1 of PIC-challenged but not saline-injected mice. Our results implicate the increase in extracellular glutamate as a mediator of seizure hypersusceptibility induced by peripheral viral challenge.
Collapse
Affiliation(s)
- Holly C Hunsberger
- Department of Neurobiology and Anatomy, School of Medicine, West Virginia University, Morgantown, West Virginia, USA
| | - Gregory W Konat
- Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, Alabama, USA
| | - Miranda N Reed
- Department of Neurobiology and Anatomy, School of Medicine, West Virginia University, Morgantown, West Virginia, USA
| |
Collapse
|
29
|
In Situ Real-Time Monitoring of Glutamate and Electrophysiology from Cortex to Hippocampus in Mice Based on a Microelectrode Array. SENSORS 2016; 17:s17010061. [PMID: 28042814 PMCID: PMC5298634 DOI: 10.3390/s17010061] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/22/2016] [Accepted: 12/26/2016] [Indexed: 01/05/2023]
Abstract
Changes in the structure and function of the hippocampus contribute to epilepsy, schizophrenia and other neurological or mental disorders of the brain. Since the function of the hippocampus depends heavily on the glutamate (Glu) signaling pathways, in situ real-time detection of Glu neurotransmitter release and electrophysiological signals in hippocampus is of great significance. To achieve the dual-mode detection in mouse hippocampus in vivo, a 16-channel implantable microelectrode array (MEA) was fabricated by micro-electromechanical system (MEMS) technology. Twelve microelectrode sites were modified with platinum black for electrophysiological recording and four sites were modified with glutamate oxidase (GluOx) and 1,3-phenylenediamine (mPD) for selective electrochemical detection of Glu. The MEA was implanted from cortex to hippocampus in mouse brain for in situ real-time monitoring of Glu and electrophysiological signals. It was found that the Glu concentration in hippocampus was roughly 50 μM higher than that in the cortex, and the firing rate of concurrently recorded spikes declined from 6.32 ± 4.35 spikes/s in cortex to 0.09 ± 0.06 spikes/s in hippocampus. The present results demonstrated that the dual-mode MEA probe was capable in neurological detections in vivo with high spatial resolution and dynamical response, which lays the foundation for further pathology studies in the hippocampus of mouse models with nervous or mental disorders.
Collapse
|
30
|
Farrand AQ, Gregory RA, Bäckman CM, Helke KL, Boger HA. Altered glutamate release in the dorsal striatum of the MitoPark mouse model of Parkinson's disease. Brain Res 2016; 1651:88-94. [PMID: 27659966 DOI: 10.1016/j.brainres.2016.09.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 09/12/2016] [Accepted: 09/18/2016] [Indexed: 11/20/2022]
Abstract
Mitochondrial dysfunction has been implicated in the degeneration of dopamine (DA) neurons in Parkinson's disease (PD). In addition, animal models of PD utilizing neurotoxins, such as 6-hydroxydopamine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, have shown that these toxins disrupt mitochondrial respiration by targeting complex I of the electron transport chain, thereby impairing DA neurons in these models. A MitoPark mouse model was created to mimic the mitochondrial dysfunction observed in the DA system of PD patients. These mice display the same phenotypic characteristics as PD, including accelerated decline in motor function and DAergic systems with age. Previously, these mice have responded to L-Dopa treatment and develop L-Dopa induced dyskinesia (LID) as they age. A potential mechanism involved in the formation of LID is greater glutamate release into the dorsal striatum as a result of altered basal ganglia neurocircuitry due to reduced nigrostriatal DA neurotransmission. Therefore, the focus of this study was to assess various indicators of glutamate neurotransmission in the dorsal striatum of MitoPark mice at an age in which nigrostriatal DA has degenerated. At 28 weeks of age, MitoPark mice had, upon KCl stimulation, greater glutamate release in the dorsal striatum compared to control mice. In addition, uptake kinetics were slower in MitoPark mice. These findings were coupled with reduced expression of the glutamate re-uptake transporter, GLT-1, thus providing an environment suitable for glutamate excitotoxic events, leading to altered physiological function in these mice.
Collapse
Affiliation(s)
- Ariana Q Farrand
- Department of Neuroscience and Center on Aging, Medical University of South Carolina, 173 Ashley Ave, BSB 403, MSC 510, Charleston, SC 29425, USA
| | - Rebecca A Gregory
- Department of Neuroscience and Center on Aging, Medical University of South Carolina, 173 Ashley Ave, BSB 403, MSC 510, Charleston, SC 29425, USA; Department of Comparative Medicine, Medical University of South Carolina, 114 Doughty St, STB 648, MSC 777, Charleston, SC 29425, USA
| | - Cristina M Bäckman
- Integrative Neuroscience Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, 251 Bayview Blvd, Baltimore, MD 21224, USA
| | - Kristi L Helke
- Department of Comparative Medicine, Medical University of South Carolina, 114 Doughty St, STB 648, MSC 777, Charleston, SC 29425, USA
| | - Heather A Boger
- Department of Neuroscience and Center on Aging, Medical University of South Carolina, 173 Ashley Ave, BSB 403, MSC 510, Charleston, SC 29425, USA.
| |
Collapse
|
31
|
Weltin A, Kieninger J, Urban GA. Microfabricated, amperometric, enzyme-based biosensors for in vivo applications. Anal Bioanal Chem 2016; 408:4503-21. [PMID: 26935934 PMCID: PMC4909808 DOI: 10.1007/s00216-016-9420-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 02/08/2016] [Accepted: 02/12/2016] [Indexed: 01/19/2023]
Abstract
Miniaturized electrochemical in vivo biosensors allow the measurement of fast extracellular dynamics of neurotransmitter and energy metabolism directly in the tissue. Enzyme-based amperometric biosensing is characterized by high specificity and precision as well as high spatial and temporal resolution. Aside from glucose monitoring, many systems have been introduced mainly for application in the central nervous system in animal models. We compare the microsensor principle with other methods applied in biomedical research to show advantages and drawbacks. Electrochemical sensor systems are easily miniaturized and fabricated by microtechnology processes. We review different microfabrication approaches for in vivo sensor platforms, ranging from simple modified wires and fibres to fully microfabricated systems on silicon, ceramic or polymer substrates. The various immobilization methods for the enzyme such as chemical cross-linking and entrapment in polymer membranes are discussed. The resulting sensor performance is compared in detail. We also examine different concepts to reject interfering substances by additional membranes, aspects of instrumentation and biocompatibility. Practical considerations are elaborated, and conclusions for future developments are presented. Graphical Abstract ᅟ.
Collapse
Affiliation(s)
- Andreas Weltin
- Laboratory for Sensors, Department of Microsystems Engineering – IMTEK, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Jochen Kieninger
- Laboratory for Sensors, Department of Microsystems Engineering – IMTEK, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| | - Gerald A. Urban
- Laboratory for Sensors, Department of Microsystems Engineering – IMTEK, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany
| |
Collapse
|
32
|
Hascup KN, Hascup ER. Soluble Amyloid-β42 Stimulates Glutamate Release through Activation of the α7 Nicotinic Acetylcholine Receptor. J Alzheimers Dis 2016; 53:337-47. [DOI: 10.3233/jad-160041] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Kevin N. Hascup
- Department of Neurology, Center for Alzheimer’s Disease and Related Disorders, Neurosciences Institute, Center for Integrated Research in Cognitive & Neural Sciences, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Erin R. Hascup
- Department of Neurology, Center for Alzheimer’s Disease and Related Disorders, Neurosciences Institute, Center for Integrated Research in Cognitive & Neural Sciences, Southern Illinois University School of Medicine, Springfield, IL, USA
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| |
Collapse
|
33
|
Parikh V, Naughton SX, Yegla B, Guzman DM. Impact of partial dopamine depletion on cognitive flexibility in BDNF heterozygous mice. Psychopharmacology (Berl) 2016; 233:1361-75. [PMID: 26861892 PMCID: PMC4814303 DOI: 10.1007/s00213-016-4229-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 01/30/2016] [Indexed: 12/17/2022]
Abstract
RATIONALE Cognitive flexibility is a key component of executive function and is disrupted in major psychiatric disorders. Brain-derived neurotrophic factor (BDNF) exerts neuromodulatory effects on synaptic transmission and cognitive/affective behaviors. However, the causal mechanisms linking BDNF hypofunction with executive deficits are not well understood. OBJECTIVES Here, we assessed the consequences of BDNF hemizygosity on cognitive flexibility in mice performing an operant conditioning task. As dopaminergic-glutamatergic interaction in the striatum is important for cognitive processing, and BDNF heterozygous (BDNF(+/-)) mice display a higher dopamine tone in the dorsal striatum, we also assessed the effects of partial striatal dopamine depletion on task performance and glutamate release. RESULTS BDNF(+/-) mice acquired discrimination learning as well as new rule learning during set-shifting as efficiently as wild-type mice. However, partial removal of striatal dopaminergic inputs with 6-hydroxydopamine (6-OHDA) impaired these cognitive processes by impeding the maintenance of a new learning strategy in both genotypes. BDNF mutants exhibited performance impairments during reversal learning, and these deficits were associated with increased perseveration to the previously acquired strategy. Partial dopamine depletion of the striatum reversed these cognitive impairments. Additionally, reduction in depolarization-evoked glutamate release noted in the dorsal striatum of BDNF(+/-) mice was not observed in 6-OHDA-infused BDNF mutants indicating normalization of glutamatergic transmission in these animals. CONCLUSIONS Our data illustrate that BDNF signaling regulates cognitive control processes presumably by maintaining striatal dopamine-glutamate balance. Moreover, aberrations in BDNF signaling may act as a common neurobiological substrate that accounts for executive dysfunction observed in multiple psychiatric conditions.
Collapse
Affiliation(s)
- Vinay Parikh
- Department of Psychology and Neuroscience Program, Temple University, Philadelphia, PA, 19122, USA.
| | | | | | | |
Collapse
|
34
|
A New Computational Model for Neuro-Glio-Vascular Coupling: Astrocyte Activation Can Explain Cerebral Blood Flow Nonlinear Response to Interictal Events. PLoS One 2016; 11:e0147292. [PMID: 26849643 PMCID: PMC4743967 DOI: 10.1371/journal.pone.0147292] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 01/01/2016] [Indexed: 12/31/2022] Open
Abstract
Developing a clear understanding of the relationship between cerebral blood flow (CBF) response and neuronal activity is of significant importance because CBF increase is essential to the health of neurons, for instance through oxygen supply. This relationship can be investigated by analyzing multimodal (fMRI, PET, laser Doppler…) recordings. However, the important number of intermediate (non-observable) variables involved in the underlying neurovascular coupling makes the discovery of mechanisms all the more difficult from the sole multimodal data. We present a new computational model developed at the population scale (voxel) with physiologically relevant but simple equations to facilitate the interpretation of regional multimodal recordings. This model links neuronal activity to regional CBF dynamics through neuro-glio-vascular coupling. This coupling involves a population of glial cells called astrocytes via their role in neurotransmitter (glutamate and GABA) recycling and their impact on neighboring vessels. In epilepsy, neuronal networks generate epileptiform discharges, leading to variations in astrocytic and CBF dynamics. In this study, we took advantage of these large variations in neuronal activity magnitude to test the capacity of our model to reproduce experimental data. We compared simulations from our model with isolated epileptiform events, which were obtained in vivo by simultaneous local field potential and laser Doppler recordings in rats after local bicuculline injection. We showed a predominant neuronal contribution for low level discharges and a significant astrocytic contribution for higher level discharges. Besides, neuronal contribution to CBF was linear while astrocytic contribution was nonlinear. Results thus indicate that the relationship between neuronal activity and CBF magnitudes can be nonlinear for isolated events and that this nonlinearity is due to astrocytic activity, highlighting the importance of astrocytes in the interpretation of regional recordings.
Collapse
|
35
|
Modulation by Trace Amine-Associated Receptor 1 of Experimental Parkinsonism, L-DOPA Responsivity, and Glutamatergic Neurotransmission. J Neurosci 2016; 35:14057-69. [PMID: 26468205 DOI: 10.1523/jneurosci.1312-15.2015] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Parkinson's disease (PD) is a movement disorder characterized by a progressive loss of nigrostriatal dopaminergic neurons. Restoration of dopamine transmission by l-DOPA relieves symptoms of PD but causes dyskinesia. Trace Amine-Associated Receptor 1 (TAAR1) modulates dopaminergic transmission, but its role in experimental Parkinsonism and l-DOPA responses has been neglected. Here, we report that TAAR1 knock-out (KO) mice show a reduced loss of dopaminergic markers in response to intrastriatal 6-OHDA administration compared with wild-type (WT) littermates. In contrast, the TAAR1 agonist RO5166017 aggravated degeneration induced by intrastriatal 6-OHDA in WT mice. Subchronic l-DOPA treatment of TAAR1 KO mice unilaterally lesioned with 6-OHDA in the medial forebrain bundle resulted in more pronounced rotational behavior and dyskinesia than in their WT counterparts. The enhanced behavioral sensitization to l-DOPA in TAAR1 KO mice was paralleled by increased phosphorylation of striatal GluA1 subunits of AMPA receptors. Conversely, RO5166017 counteracted both l-DOPA-induced rotation and dyskinesia as well as AMPA receptor phosphorylation. Underpinning a role for TAAR1 receptors in modulating glutamate neurotransmission, intrastriatal application of RO5166017 prevented the increase of evoked corticostriatal glutamate release provoked by dopamine deficiency after 6-OHDA-lesions or conditional KO of Nurr1. Finally, inhibition of corticostriatal glutamate release by TAAR1 showed mechanistic similarities to that effected by activation of dopamine D2 receptors. These data unveil a role for TAAR1 in modulating the degeneration of dopaminergic neurons, the behavioral response to l-DOPA, and presynaptic and postsynaptic glutamate neurotransmission in the striatum, supporting their relevance to the pathophysiology and, potentially, management of PD. SIGNIFICANCE STATEMENT Parkinson's disease (PD) is characterized by a progressive loss of nigrostriatal dopaminergic neurons. Restoration of dopamine transmission by l-DOPA relieves symptoms of PD but causes severe side effects. Trace Amine-Associated Receptor 1 (TAAR1) modulates dopaminergic transmission, but its role in PD and l-DOPA responses has been neglected. Here, we report that TAAR1 potentiates the degeneration of dopaminergic neurons and attenuates the behavioral response to l-DOPA and presynaptic and postsynaptic glutamate neurotransmission in the striatum, supporting the relevance of TAAR1 to the pathophysiology and, potentially, management of PD.
Collapse
|
36
|
p11 modulates L-DOPA therapeutic effects and dyskinesia via distinct cell types in experimental Parkinsonism. Proc Natl Acad Sci U S A 2016; 113:1429-34. [PMID: 26787846 DOI: 10.1073/pnas.1524303113] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The reduced movement repertoire of Parkinson's disease (PD) is mainly due to degeneration of nigrostriatal dopamine neurons. Restoration of dopamine transmission by levodopa (L-DOPA) relieves motor symptoms of PD but often causes disabling dyskinesias. Subchronic L-DOPA increases levels of adaptor protein p11 (S100A10) in dopaminoceptive neurons of the striatum. Using experimental mouse models of Parkinsonism, we report here that global p11 knockout (KO) mice develop fewer jaw tremors in response to tacrine. Following L-DOPA, global p11KO mice show reduced therapeutic responses on rotational motor sensitization, but also develop less dyskinetic side effects. Studies using conditional p11KO mice reveal that distinct cell populations mediate these therapeutic and side effects. Selective deletion of p11 in cholinergic acetyltransferase (ChAT) neurons reduces tacrine-induced tremor. Mice lacking p11 in dopamine D2R-containing neurons have a reduced response to L-DOPA on the therapeutic parameters, but develop dyskinetic side effects. In contrast, mice lacking p11 in dopamine D1R-containing neurons exhibit tremor and rotational responses toward L-DOPA, but develop less dyskinesia. Moreover, coadministration of rapamycin with L-DOPA counteracts L-DOPA-induced dyskinesias in wild-type mice, but not in mice lacking p11 in D1R-containing neurons. 6-OHDA lesioning causes an increase of evoked striatal glutamate release in wild type, but not in global p11KO mice, indicating that altered glutamate neurotransmission could contribute to the reduced L-DOPA responsivity. These data demonstrate that p11 located in ChAT or D2R-containing neurons is involved in regulating therapeutic actions in experimental PD, whereas p11 in D1R-containing neurons underlies the development of L-DOPA-induced dyskinesias.
Collapse
|
37
|
Murakami G, Nakamura M, Takita M, Ishida Y, Ueki T, Nakahara D. Brain Rewarding Stimulation Reduces Extracellular Glutamate Through Glial Modulation in Medial Prefrontal Cortex of Rats. Neuropsychopharmacology 2015; 40:2686-95. [PMID: 25924203 PMCID: PMC4864644 DOI: 10.1038/npp.2015.115] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 03/16/2015] [Accepted: 03/24/2015] [Indexed: 12/29/2022]
Abstract
Growing evidence implicates a critical involvement of prefrontal glial modulation of extracellular glutamate (GLU) in aversive behaviors. However, nothing is known about whether prefrontal glial cells modulate GLU levels in rewarding behaviors. To address this question, we measured GLU efflux in the medial prefrontal cortex (PFC) of rats associated with rewarding behaviors. We used intracranial self-stimulation (ICSS) of the medial forebrain bundle (MFB) as the rewarding behavior. GLU was indirectly measured using microdialysis combined with on-line fluorometric detection of NADH resulting from the reaction of GLU and NAD(+) catalyzed by GLU dehydrogenase with a time resolution of 1 min. ICSS caused a minute-by-minute change of extracellular GLU in the medial PFC, with a slight decrease during the stimulation, followed by an increase afterward. This bidirectional change was tetrodotoxin insensitive and abolished by the gliotoxin fluorocitrate. To confirm and extend the previous studies of aversion-induced increase of extracellular GLU in the medial PFC, we also measured prefrontal GLU efflux associated with an aversive stimulation, immobilization stress. The temporal change in extracellular GLU caused by this stress was markedly different from that observed during ICSS. A rapid increase in GLU was detected during the aversive stimulation, followed by a large increase afterward. This bimodal change was tetrodotoxin insensitive, similar to that detected for ICSS. These findings indicate a bidirectional regulation of extracellular GLU by prefrontal glial cells associated with rat ICSS behavior, and reveal that glial modulation of GLU neurochemistry in the medial PFC contributes to rewarding as well as aversive behaviors in rats.
Collapse
Affiliation(s)
- Gen Murakami
- Division of Psychology and Behavioral Neuroscience, Department of Integrated Human Sciences, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Masato Nakamura
- Division of Psychology and Behavioral Neuroscience, Department of Integrated Human Sciences, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Masatoshi Takita
- Cognition and Action Research Group, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
| | - Yasushi Ishida
- Department of Psychiatry, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Takatoshi Ueki
- Department of Anatomy and Cell Biology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
- Department of Biofunctional Imaging, Medical Photonics Center, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Daiichiro Nakahara
- Division of Psychology and Behavioral Neuroscience, Department of Integrated Human Sciences, Hamamatsu University School of Medicine, Hamamatsu, Japan
- Department of Biofunctional Imaging, Medical Photonics Center, Hamamatsu University School of Medicine, Hamamatsu, Japan
| |
Collapse
|
38
|
López-Valenzuela CL, Morales-Villagrán A, Medina-Ceja L. A novel method for simultaneous glutamate and extracellular activity measurement in brain slices with high temporal resolution. Talanta 2015; 144:1231-8. [PMID: 26452952 DOI: 10.1016/j.talanta.2015.08.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 08/02/2015] [Accepted: 08/05/2015] [Indexed: 11/30/2022]
Abstract
Measurement of neurotransmitters during normal or altered function in cerebral slices could be an important tool to better understand the relationship between biochemical changes and electrophysiological activity. Some attempts of this analysis have been made; however, the current techniques do not have the appropriate time resolution to establish this relationship. The use of electrochemical biosensors has allowed for good time resolution, but problems related to the reduction of signal noise and biofouling of the electrode surface could be an important issue. In this work, we propose a new alternative to simultaneously measure glutamate and electrical activity with a high temporal resolution in brain slices. This approach is based on the use of enzymatic reactors that generate a fluorescent derivative from glutamate that can be measured at high temporal resolution. The results presented here show a reliable measurement of this neurotransmitter in brain slices obtained from intact animals under the effect of a glutamate transporter blocker DL-threo-beta-benzyloxyaspartate as well as the potassium channel blocker 4-aminopyridine. Differences in the levels of glutamate and high frequency and amplitude discharges as an effect of drug administration were found in brain slices obtained from epileptic rats (p<0.05). In conclusion, this method could be used to measure neurotransmitter concentration online at a near physiological temporal resolution, which can then be correlated to the electrical activity that is simultaneously recorded.
Collapse
Affiliation(s)
- C L López-Valenzuela
- Laboratory of Neurophysiology and Neurochemistry, Department of Cellular and Molecular Biology, CUCBA, University of Guadalajara, Jalisco, Mexico
| | - A Morales-Villagrán
- Laboratory of Neurophysiology and Neurochemistry, Department of Cellular and Molecular Biology, CUCBA, University of Guadalajara, Jalisco, Mexico.
| | - L Medina-Ceja
- Laboratory of Neurophysiology and Neurochemistry, Department of Cellular and Molecular Biology, CUCBA, University of Guadalajara, Jalisco, Mexico
| |
Collapse
|
39
|
Malvaez M, Greenfield VY, Wang AS, Yorita AM, Feng L, Linker KE, Monbouquette HG, Wassum KM. Basolateral amygdala rapid glutamate release encodes an outcome-specific representation vital for reward-predictive cues to selectively invigorate reward-seeking actions. Sci Rep 2015; 5:12511. [PMID: 26212790 PMCID: PMC4648450 DOI: 10.1038/srep12511] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 06/17/2015] [Indexed: 11/09/2022] Open
Abstract
Environmental stimuli have the ability to generate specific representations of the rewards they predict and in so doing alter the selection and performance of reward-seeking actions. The basolateral amygdala participates in this process, but precisely how is unknown. To rectify this, we monitored, in near-real time, basolateral amygdala glutamate concentration changes during a test of the ability of reward-predictive cues to influence reward-seeking actions (Pavlovian-instrumental transfer). Glutamate concentration was found to be transiently elevated around instrumental reward seeking. During the Pavlovian-instrumental transfer test these glutamate transients were time-locked to and correlated with only those actions invigorated by outcome-specific motivational information provided by the reward-predictive stimulus (i.e., actions earning the same specific outcome as predicted by the presented CS). In addition, basolateral amygdala AMPA, but not NMDA glutamate receptor inactivation abolished the selective excitatory influence of reward-predictive cues over reward seeking. These data support [corrected] the hypothesis that transient glutamate release in the BLA can encode the outcome-specific motivational information provided by reward-predictive stimuli.
Collapse
Affiliation(s)
| | | | - Alice S. Wang
- Dept. of Psychology, UCLA, Los Angeles, CA 90095, USA
| | | | - Lili Feng
- Dept. of Chemical Engineering, UCLA, Los Angeles, CA 90095, USA
| | - Kay E. Linker
- Dept. of Psychology, UCLA, Los Angeles, CA 90095, USA
| | | | - Kate M. Wassum
- Dept. of Psychology, UCLA, Los Angeles, CA 90095, USA
- Brain Research Institute, UCLA, Los Angeles, CA 90095, USA
| |
Collapse
|
40
|
Özel RE, Hayat A, Andreescu S. RECENT DEVELOPMENTS IN ELECTROCHEMICAL SENSORS FOR THE DETECTION OF NEUROTRANSMITTERS FOR APPLICATIONS IN BIOMEDICINE. ANAL LETT 2015; 48:1044-1069. [PMID: 26973348 PMCID: PMC4787221 DOI: 10.1080/00032719.2014.976867] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Neurotransmitters are important biological molecules that are essential to many neurophysiological processes including memory, cognition, and behavioral states. The development of analytical methodologies to accurately detect neurotransmitters is of great importance in neurological and biological research. Specifically designed microelectrodes or microbiosensors have demonstrated potential for rapid, real-time measurements with high spatial resolution. Such devices can facilitate study of the role and mechanism of action of neurotransmitters and can find potential uses in biomedicine. This paper reviews the current status and recent advances in the development and application of electrochemical sensors for the detection of small-molecule neurotransmitters. Measurement challenges and opportunities of electroanalytical methods to advance study and understanding of neurotransmitters in various biological models and disease conditions are discussed.
Collapse
Affiliation(s)
- Rıfat Emrah Özel
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, USA. Fax: 3152686610; Tel: 3152682394
| | - Akhtar Hayat
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, USA. Fax: 3152686610; Tel: 3152682394
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Lahore, Pakistan
| | - Silvana Andreescu
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, USA. Fax: 3152686610; Tel: 3152682394
| |
Collapse
|
41
|
Opris I, Fuqua JL, Gerhardt GA, Hampson RE, Deadwyler SA. Prefrontal cortical recordings with biomorphic MEAs reveal complex columnar-laminar microcircuits for BCI/BMI implementation. J Neurosci Methods 2015; 244:104-13. [PMID: 24954713 PMCID: PMC4595476 DOI: 10.1016/j.jneumeth.2014.05.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 05/22/2014] [Accepted: 05/24/2014] [Indexed: 01/25/2023]
Abstract
The mammalian prefrontal cortex known as the seat of high brain functions uses a six layer distribution of minicolumnar neurons to coordinate the integration of sensory information and the selection of relevant signals for goal driven behavior. To reveal the complex functionality of these columnar microcircuits we employed simultaneous recordings with several configurations of biomorphic microelectrode arrays (MEAs) within cortical layers in adjacent minicolumns, in four nohuman primates (NHPs) performing a delayed match-to-sample (DMS) visual discrimination task. We examined: (1) the functionality of inter-laminar, and inter-columnar interactions between pairs of cells in the same or different minicolumns by use of normalized cross-correlation histograms (CCH), (2) the modulation of glutamate concentration in layer 2/3, and (3) the potential interactions within these microcircuits. The results demonstrate that neurons in both infra-granular and supra-granular layers interact through inter-laminar loops, as well as through intra-laminar to produce behavioral response signals. These results provide new insights into the manner in which prefrontal cortical microcircuitry integrates sensory stimuli used to provide behaviorally relevant signals that may be implemented in brain computer/machine interfaces (BCI/BMIs) during performance of the task.
Collapse
Affiliation(s)
- Ioan Opris
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, USA.
| | - Joshua L Fuqua
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Greg A Gerhardt
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington, KY, USA
| | - Robert E Hampson
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Samuel A Deadwyler
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC, USA.
| |
Collapse
|
42
|
Keighron JD, Wigström J, Kurczy ME, Bergman J, Wang Y, Cans AS. Amperometric detection of single vesicle acetylcholine release events from an artificial cell. ACS Chem Neurosci 2015; 6:181-8. [PMID: 25565357 DOI: 10.1021/cn5002667] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Acetylcholine is a highly abundant nonelectroactive neurotransmitter in the mammalian central nervous system. Neurochemical release occurs on the millisecond time scale, requiring a fast, sensitive sensor such as an enzymatic amperometric electrode. Typically, the enzyme used for enzymatic electrochemical sensors is applied in excess to maximize signal. Here, in addition to sensitivity, we have also sought to maximize temporal resolution, by designing a sensor that is sensitive enough to work at near monolayer enzyme coverage. Reducing the enzyme layer thickness increases sensor temporal resolution by decreasing the distance and reducing the diffusion time for the enzyme product to travel to the sensor surface for detection. In this instance, the sensor consists of electrodeposited gold nanoparticle modified carbon fiber microelectrodes (CFMEs). Enzymes often are sensitive to curvature upon surface adsorption; thus, it was important to deposit discrete nanoparticles to maintain enzyme activity while depositing as much gold as possible to maximize enzyme coverage. To further enhance sensitivity, the enzymes acetylcholinesterase (AChE) and choline oxidase (ChO) were immobilized onto the gold nanoparticles at the previously determined optimal ratio (1:10 AChE/ChO) for most efficient sequential enzymatic activity. This optimization approach has enabled the rapid detection to temporally resolve single vesicle acetylcholine release from an artificial cell. The sensor described is a significant advancement in that it allows for the recording of acetylcholine release on the order of the time scale for neurochemical release in secretory cells.
Collapse
Affiliation(s)
- Jacqueline D. Keighron
- Department
of Chemical and Biological Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Joakim Wigström
- Department
of Chemical and Biological Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Michael E. Kurczy
- Department
of Chemical and Biological Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Jenny Bergman
- Department
of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg, Sweden
| | - Yuanmo Wang
- Department
of Chemical and Biological Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Ann-Sofie Cans
- Department
of Chemical and Biological Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| |
Collapse
|
43
|
Farrand AQ, Gregory RA, Scofield MD, Helke KL, Boger HA. Effects of aging on glutamate neurotransmission in the substantia nigra of Gdnf heterozygous mice. Neurobiol Aging 2014; 36:1569-76. [PMID: 25577412 DOI: 10.1016/j.neurobiolaging.2014.11.017] [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] [Received: 07/01/2014] [Revised: 11/11/2014] [Accepted: 11/25/2014] [Indexed: 12/12/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) helps protect dopaminergic neurons in the nigrostriatal tract. Although the cause of nigrostriatal degeneration is unknown, one theory is that excess glutamate from the subthalamic nucleus results in excitotoxic events in the substantia nigra (SN). Because dopaminergic degeneration is accompanied by a reduction in GDNF, we examined glutamate neurotransmission in the SN using a Gdnf heterozygous mouse model (Gdnf(+/-)) at 8 and 12 months of age. At 8 months, Gdnf(+/-) mice have greater glutamate release and higher basal glutamate levels, which precede the SN dopaminergic degeneration observed at 12 months of age. However, at 12 months, Gdnf(+/-) mice have lower basal levels of glutamate and less glutamate release than wild-type mice. Also at 8 months, Gdnf(+/-) mice have lower levels of glutamate transporter-1 and greater glial fibrillary acidic protein levels in the SN compared with wild-type mice, differences that increase with age. These data suggest that reduced levels of GDNF induce excess glutamate release and dysregulation of glutamate transporter-1, causing excitotoxicity in the SN that precedes dopaminergic degeneration.
Collapse
Affiliation(s)
- Ariana Q Farrand
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, USA
| | - Rebecca A Gregory
- Department of Comparative Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Michael D Scofield
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, USA
| | - Kristi L Helke
- Department of Comparative Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Heather A Boger
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, USA.
| |
Collapse
|
44
|
Parikh V, Naughton SX, Shi X, Kelley LK, Yegla B, Tallarida CS, Rawls SM, Unterwald EM. Cocaine-induced neuroadaptations in the dorsal striatum: Glutamate dynamics and behavioral sensitization. Neurochem Int 2014; 75:54-65. [DOI: 10.1016/j.neuint.2014.05.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 05/13/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022]
|
45
|
Hascup KN, Hascup ER. Electrochemical techniques for subsecond neurotransmitter detection in live rodents. Comp Med 2014; 64:249-55. [PMID: 25296011 PMCID: PMC4170089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 11/12/2013] [Accepted: 01/09/2014] [Indexed: 06/03/2023]
Abstract
Alterations in neurotransmission have been implicated in numerous neurodegenerative and neuropsychiatric disorders, including Alzheimer disease, Parkinson disease, epilepsy, and schizophrenia. Unfortunately, few techniques support the measurement of real-time changes in neurotransmitter levels over multiple days, as is essential for ethologic and pharmacodynamic testing. Microdialysis is commonly used for these research paradigms, but its poor temporal and spatial resolution make this technique inadequate for measuring the rapid dynamics (milliseconds to seconds) of fast signaling neurotransmitters, such as glutamate and acetylcholine. Enzymatic microelectrode arrays (biosensors) coupled with electrochemical recording techniques have demonstrated fast temporal resolution (less than 1 s), excellent spatial resolution (micron-scale), low detection limits (≤200 nM), and minimal damage (50 to 100 μm) to surrounding brain tissue. Here we discuss the benefits, methods, and animal welfare considerations of using platinum microelectrodes on a ceramic substrate for enzyme-based electrochemical recording techniques for real-time in vivo neurotransmitter recordings in both anesthetized and awake, freely moving rodents.
Collapse
Affiliation(s)
- Kevin N Hascup
- Departments of Neurology and Pharmacology, Center for Alzheimer's Disease and Related Disorders, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Erin R Hascup
- Departments of Neurology and Pharmacology, Center for Alzheimer's Disease and Related Disorders, Southern Illinois University School of Medicine, Springfield, Illinois, USA.
| |
Collapse
|
46
|
Sirca D, Vardeu A, Pinna M, Diana M, Enrico P. A robust, state-of-the-art amperometric microbiosensor for glutamate detection. Biosens Bioelectron 2014; 61:526-31. [PMID: 24951923 DOI: 10.1016/j.bios.2014.04.054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 04/10/2014] [Accepted: 04/29/2014] [Indexed: 10/25/2022]
Abstract
Scientific knowledge of glutamate (GLU) neurobiology is severely hampered by the inadequacy of the available in vivo brain sampling techniques. Due to the crucial role of GLU in central nervous system function and pathology, the development of a reliable sampling device is mandatory. GLU biosensor holds potential to address many of the known issues of in vivo GLU measurement. We report here on the development and test of a labor- and cost-effective microbiosensor, suitable to be applied for measuring brain GLU. A glycerol-based cryopreservation method was also tested. Needle type Pt biosensors were coated with a permselective Nafion-Poly(o-phenylenediamine) layer and cross-linked to l-glutamate oxidase with poly(ethylene glycol) diglycidyl ether. Tested in vitro, the device shows high sensitivity and specificity for GLU, while being poorly influenced by common interfering substances such as ascorbate, dopamine and dihydroxyphenylacetic acid. Further, the cryopreservation procedure kept sensitivity unaltered for 30 days and possibly longer. We conclude that a highly efficient GLU biosensor of minimal dimensions can be consistently and affordably constructed with relative ease. Together with the possibility of cryopreservation this shall foster diffusion and exploitation of GLU biosensors technology.
Collapse
Affiliation(s)
- Donatella Sirca
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Antonella Vardeu
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Milo Pinna
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Marco Diana
- "G. Minardi" Laboratory of Cognitive Neuroscience, Department of Chemistry and Pharmacy, University of Sassari, Sassari, Italy
| | - Paolo Enrico
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| |
Collapse
|
47
|
NMDA receptor antagonists ketamine and Ro25-6981 inhibit evoked release of glutamate in vivo in the subiculum. Transl Psychiatry 2014; 4:e395. [PMID: 24893066 PMCID: PMC4080320 DOI: 10.1038/tp.2014.39] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 04/22/2014] [Indexed: 01/20/2023] Open
Abstract
Preclinical and clinical data have identified ketamine, a non-selective NMDAR (N-methyl-D-aspartate receptor) antagonist, as a promising medication for patients who do not respond to treatment with monoamine-based antidepressants. Moreover, unlike the current monoamine-based antidepressants, ketamine has a long-lasting effect already after a single dose. The mechanisms of ketamine action remain to be fully understood. Using a recently developed microelectrode array (MEA), which allows sub-second measurements of fluctuating glutamate concentrations, we studied here the effects of in vivo local application of the ketamine and of the N2B subunit-specific antagonist Ro25-6981 upon evoked glutamate release. Both ligands inhibit glutamate release in subregions of the hippocampus and prefrontal cortex. Likewise, acute systemic ketamine treatment, at an antidepressant dose, caused a reduction in evoked glutamate release in the subiculum. We suggest that the effects of ketamine and Ro25-6981 in the subiculum could involve blockade of presynaptic NMDA receptors containing N2B subunits.
Collapse
|
48
|
A systemically-available kynurenine aminotransferase II (KAT II) inhibitor restores nicotine-evoked glutamatergic activity in the cortex of rats. Neuropharmacology 2014; 82:41-8. [PMID: 24647121 DOI: 10.1016/j.neuropharm.2014.03.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 03/06/2014] [Accepted: 03/08/2014] [Indexed: 01/01/2023]
Abstract
Kynurenic acid (KYNA) is a tryptophan metabolite that acts in the brain as an endogenous antagonist at multiple receptors, including glutamate and α7 nicotinic acetylcholine receptors. Increased levels of KYNA have been demonstrated in the brain of patients with a range of neurocognitive disorders, including schizophrenia, and are hypothesized to contribute to cognitive symptoms. Reducing KYNA levels by administering inhibitors of enzymes of the kynurenine pathway, particularly kynurenine aminotransferase II (KAT II), has been proposed as a treatment for such cognitive impairments. Here we report that administration of a systemically available KAT II inhibitor, PF-04859989, restores glutamate release events ("transients") evoked by pressure ejections of nicotine into the prefrontal cortex of rats exhibiting elevated KYNA levels. Nicotine-evoked glutamatergic transients can be reliably evoked and recorded after repeated pressure ejections of nicotine over 4-5 h. Systemic administration of l-kynurenine (100 mg/kg; i.p.) significantly increased frontal cortical KYNA levels and greatly attenuated the amplitude of nicotine-evoked glutamatergic transients. Systemic administration of PF-04859989 30 min prior to administration of l-kynurenine, but not when administered 30 min after l-kynurenine, restored glutamatergic transients recorded up to 75 min after the administration of the KAT II inhibitor. Furthermore, the KAT II inhibitor significantly reversed l-kynurenine-induced elevations of brain KYNA levels. The KAT II inhibitor did not affect nicotine-evoked glutamatergic transients in rats not pre-treated with l-kynurenine. Because PF-04859989 restores evoked glutamate signaling it therefore is a promising therapeutic compound for benefiting the cognitive symptoms of schizophrenia and other disorders associated with elevated brain KYNA levels.
Collapse
|
49
|
Bidirectional regulation of emotional memory by 5-HT1B receptors involves hippocampal p11. Mol Psychiatry 2013; 18:1096-105. [PMID: 23032875 PMCID: PMC3781317 DOI: 10.1038/mp.2012.130] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 07/16/2012] [Accepted: 07/23/2012] [Indexed: 12/25/2022]
Abstract
Cognitive impairments are common in depression and involve dysfunctional serotonin neurotransmission. The 5-HT1B receptor (5-HT(1B)R) regulates serotonin transmission, via presynaptic receptors, but can also affect transmitter release at heterosynaptic sites. This study aimed at investigating the roles of the 5-HT(1B)R, and its adapter protein p11, in emotional memory and object recognition memory processes by the use of p11 knockout (p11KO) mice, a genetic model for aspects of depression-related states. 5-HT(1B)R agonist treatment induced an impairing effect on emotional memory in wild type (WT) mice. In comparison, p11KO mice displayed reduced long-term emotional memory performance. Unexpectedly, 5-HT(1B)R agonist stimulation enhanced memory in p11KO mice, and this atypical switch was reversed after hippocampal adeno-associated virus mediated gene transfer of p11. Notably, 5-HT(1B)R stimulation increased glutamatergic neurotransmission in the hippocampus in p11KO mice, but not in WT mice, as measured by both pre- and postsynaptic criteria. Magnetic resonance spectroscopy demonstrated global hippocampal reductions of inhibitory GABA, which may contribute to the memory enhancement and potentiation of pre- and post-synaptic measures of glutamate transmission by a 5-HT(1B)R agonist in p11KO mice. It is concluded that the level of hippocampal p11 determines the directionality of 5-HT(1B)R action on emotional memory processing and modulates hippocampal functionality. These results emphasize the importance of using relevant disease models when evaluating the role of serotonin neurotransmission in cognitive deficits related to psychiatric disorders.
Collapse
|
50
|
Burmeister JJ, Davis VA, Quintero JE, Pomerleau F, Huettl P, Gerhardt GA. Glutaraldehyde cross-linked glutamate oxidase coated microelectrode arrays: selectivity and resting levels of glutamate in the CNS. ACS Chem Neurosci 2013; 4:721-8. [PMID: 23650904 DOI: 10.1021/cn4000555] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Glutaraldehyde is widely used as a cross-linking agent for enzyme immobilization onto microelectrodes. Recent studies and prior reports indicate changes in enzyme activity and selectivity with certain glutaraldehyde cross-linking procedures that may jeopardize the performance of microelectrode recordings and lead to falsely elevated responses in biological systems. In this study, the sensitivity of glutaraldehyde cross-linked glutamate oxidase-based microelectrode arrays to 22 amino acids was tested and compared to glutamate. As expected, responses to electroactive amino acids (Cys, Tyr, Trp) were detected at both nonenzyme-coated and enzyme-coated microelectrodes sites, while the remaining amino acids yielded no detectable responses. Electroactive amino acids were effectively blocked with a m-phenylene diamine (mPD) layer and, subsequently, no responses were detected. Preliminary results on the use of poly(ethylene glycol) diglycidyl ether (PEGDE) as a potentially more reliable cross-linking agent for the immobilization of glutamate oxidase onto ceramic-based microelectrode arrays are reported and show no significant advantages over glutaraldehyde as we observe comparable selectivities and responses. These results support that glutaraldehyde-cross-linked glutamate oxidase retains sufficient enzyme specificity for accurate in vivo brain measures of tonic and phasic glutamate levels when immobilized using specific "wet" coating procedures.
Collapse
Affiliation(s)
- Jason J. Burmeister
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Verda A. Davis
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Jorge E. Quintero
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Francois Pomerleau
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Peter Huettl
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| | - Greg A. Gerhardt
- Department
of Anatomy and Neurobiology, Parkinson’s Disease Translational
Research Center of Excellence, ‡Center for Microelectrode Technology, University of Kentucky, Lexington, Kentucky 40536-0098, United States
| |
Collapse
|