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Marinina KS, Bezprozvanny IB, Egorova PA. A combination of chlorzoxazone and folic acid improves recognition memory, anxiety and depression in SCA3-84Q mice. Hum Mol Genet 2024; 33:1406-1419. [PMID: 38727562 PMCID: PMC11305683 DOI: 10.1093/hmg/ddae079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 04/30/2024] [Indexed: 08/09/2024] Open
Abstract
Spinocerebellar ataxia type 3 (SCA3), also known as Machado-Joseph disease, is reported to be the most common type of autosomal dominant cerebellar ataxia (ADCA). SCA3 patients suffer from a progressive decline in motor coordination and other disease-associated symptoms. Moreover, recent studies have reported that SCA3 patients also exhibit symptoms of cerebellar cognitive affective syndrome (CCAS). We previously observed signs of CCAS in mouse model of SCA3. Particularly, SCA3-84Q mice suffer from anxiety, recognition memory decline, and also exhibit signs of low mood and aversion to activity. Here we studied the effect of long-term injections of SK channels activator chlorzoxazone (CHZ) together and separately with the folic acid (FA) on the cerebellar Purkinje cell (PC) firing and histology, and also on the motor and cognitive functions as well as mood alterations in SCA3-84Q hemizygous transgenic mice. We realized that both CHZ and CHZ-FA combination had similar positive effect on pure cerebellum impairments including PC firing precision, PC histology, and motor performance in SCA3-84Q mice. However, only the CHZ-FA combination, but not CHZ, had significantly ameliorated the signs of anxiety and depression, and also noticeably improved recognition memory in SCA3-84Q mice. Our results suggest that the combination therapy for both ataxia and non-motor symptoms is required for the complex treatment of ADCA.
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Affiliation(s)
- Ksenia S Marinina
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, 29 Polytechnicheskaya str., St. Petersburg 195251, Russia
| | - Ilya B Bezprozvanny
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9040, United States
| | - Polina A Egorova
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, 29 Polytechnicheskaya str., St. Petersburg 195251, Russia
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2
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Yakhnitsa V, Thompson J, Ponomareva O, Ji G, Kiritoshi T, Mahimainathan L, Molehin D, Pruitt K, Neugebauer V. Dysfunction of Small-Conductance Ca 2+-Activated Potassium (SK) Channels Drives Amygdala Hyperexcitability and Neuropathic Pain Behaviors: Involvement of Epigenetic Mechanisms. Cells 2024; 13:1055. [PMID: 38920682 PMCID: PMC11201618 DOI: 10.3390/cells13121055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 06/07/2024] [Accepted: 06/10/2024] [Indexed: 06/27/2024] Open
Abstract
Neuroplasticity in the amygdala and its central nucleus (CeA) is linked to pain modulation and pain behaviors, but cellular mechanisms are not well understood. Here, we addressed the role of small-conductance Ca2+-activated potassium (SK) channels in pain-related amygdala plasticity. The facilitatory effects of the intra-CeA application of an SK channel blocker (apamin) on the pain behaviors of control rats were lost in a neuropathic pain model, whereas an SK channel activator (NS309) inhibited pain behaviors in neuropathic rats but not in sham controls, suggesting the loss of the inhibitory behavioral effects of amygdala SK channels. Brain slice electrophysiology found hyperexcitability of CeA neurons in the neuropathic pain condition due to the loss of SK channel-mediated medium afterhyperpolarization (mAHP), which was accompanied by decreased SK2 channel protein and mRNA expression, consistent with a pretranscriptional mechanisms. The underlying mechanisms involved the epigenetic silencing of the SK2 gene due to the increased DNA methylation of the CpG island of the SK2 promoter region and the change in methylated CpG sites in the CeA in neuropathic pain. This study identified the epigenetic dysregulation of SK channels in the amygdala (CeA) as a novel mechanism of neuropathic pain-related plasticity and behavior that could be targeted to control abnormally enhanced amygdala activity and chronic neuropathic pain.
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Affiliation(s)
- Vadim Yakhnitsa
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Jeremy Thompson
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Olga Ponomareva
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Guangchen Ji
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Takaki Kiritoshi
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Lenin Mahimainathan
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Deborah Molehin
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Kevin Pruitt
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Volker Neugebauer
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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Blankenship HE, Carter KA, Cassidy NT, Markiewicz AN, Thellmann MI, Sharpe AL, Freeman WM, Beckstead MJ. VTA dopamine neurons are hyperexcitable in 3xTg-AD mice due to casein kinase 2-dependent SK channel dysfunction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.16.567486. [PMID: 38014232 PMCID: PMC10680865 DOI: 10.1101/2023.11.16.567486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Alzheimer's disease (AD) patients exhibit neuropsychiatric symptoms that extend beyond classical cognitive deficits, suggesting involvement of subcortical areas. Here, we investigated the role of midbrain dopamine (DA) neurons in AD using the amyloid + tau-driven 3xTg-AD mouse model. We found deficits in reward-based operant learning in AD mice, suggesting possible VTA DA neuron dysregulation. Physiological assessment revealed hyperexcitability and disrupted firing in DA neurons caused by reduced activity of small-conductance calcium-activated potassium (SK) channels. RNA sequencing from contents of single patch-clamped DA neurons (Patch-seq) identified up-regulation of the SK channel modulator casein kinase 2 (CK2). Pharmacological inhibition of CK2 restored SK channel activity and normal firing patterns in 3xTg-AD mice. These findings shed light on a complex interplay between neuropsychiatric symptoms and subcortical circuits in AD, paving the way for novel treatment strategies.
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Kelly L, Brown C, Gibbard AG, Jackson T, Swinny JD. Subunit-specific expression and function of AMPA receptors in the mouse locus coeruleus. J Anat 2023; 243:813-825. [PMID: 37391270 PMCID: PMC10557397 DOI: 10.1111/joa.13922] [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: 02/02/2023] [Revised: 06/17/2023] [Accepted: 06/19/2023] [Indexed: 07/02/2023] Open
Abstract
The locus coeruleus (LC) provides the principal supply of noradrenaline (NA) to the brain, thereby modulating an array of brain functions. The release of NA, and therefore its impact on the brain, is governed by LC neuronal excitability. Glutamatergic axons, from various brain regions, topographically innervate different LC sub-domains and directly alter LC excitability. However, it is currently unclear whether glutamate receptor sub-classes, such as α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, are divergently expressed throughout the LC. Immunohistochemistry and confocal microscopy were used to identify and localise individual GluA subunits in the mouse LC. Whole-cell patch clamp electrophysiology and subunit-preferring ligands were used to assess their impact on LC spontaneous firing rate (FR). GluA1 immunoreactive clusters were associated with puncta immunoreactive for VGLUT2 on somata, and VGLUT1 on distal dendrites. GluA4 was associated with these synaptic markers only in the distal dendrites. No specific signal was detected for the GluA2-3 subunits. The GluA1/2 receptor agonist (S)-CPW 399 increased LC FR, whilst the GluA1/3 receptor antagonist philanthotoxin-74 decreased it. 4-[2-(phenylsulfonylamino)ethylthio]-2,6-difluoro-phenoxyacetamide (PEPA), a positive allosteric modulator of GluA3/4 receptors, had no significant effect on spontaneous FR. The data suggest distinct AMPA receptor subunits are targeted to different LC afferent inputs and have contrasting effects on spontaneous neuronal excitability. This precise expression profile could be a mechanism for LC neurons to integrate diverse information contained in various glutamate afferents.
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Affiliation(s)
- Louise Kelly
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Christopher Brown
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Adina G. Gibbard
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Torquil Jackson
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Jerome D. Swinny
- School of Pharmacy & Biomedical SciencesUniversity of PortsmouthPortsmouthUK
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Brofiga M, Losacco S, Poggio F, Zerbo RA, Milanese M, Massobrio P, Burlando B. Multiple neuron clusters on Micro-Electrode Arrays as an in vitro model of brain network. Sci Rep 2023; 13:15604. [PMID: 37730890 PMCID: PMC10511538 DOI: 10.1038/s41598-023-42168-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 09/06/2023] [Indexed: 09/22/2023] Open
Abstract
Understanding the brain functioning is essential for governing brain processes with the aim of managing pathological network dysfunctions. Due to the morphological and biochemical complexity of the central nervous system, the development of general models with predictive power must start from in vitro brain network engineering. In the present work, we realized a micro-electrode array (MEA)-based in vitro brain network and studied its emerging dynamical properties. We obtained four-neuron-clusters (4N) assemblies by plating rat embryo cortical neurons on 60-electrode MEA with cross-shaped polymeric masks and compared the emerging dynamics with those of sister single networks (1N). Both 1N and 4N assemblies exhibited spontaneous electrical activity characterized by spiking and bursting signals up to global activation by means of network bursts. Data revealed distinct patterns of network activity with differences between 1 and 4N. Rhythmic network bursts and dominant initiator clusters suggested pacemaker activities in both assembly types, but the propagation of activation sequences was statistically influenced by the assembly topology. We proved that this rhythmic activity was ivabradine sensitive, suggesting the involvement of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, and propagated across the real clusters of 4N, or corresponding virtual clusters of 1N, with dominant initiator clusters, and nonrandom cluster activation sequences. The occurrence of nonrandom series of identical activation sequences in 4N revealed processes possibly ascribable to neuroplasticity. Hence, our multi-network dissociated cortical assemblies suggest the relevance of pacemaker neurons as essential elements for generating brain network electrophysiological patterns; indeed, such evidence should be considered in the development of computational models for envisaging network behavior both in physiological and pathological conditions.
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Affiliation(s)
- Martina Brofiga
- Department of Informatics, Bioengineering, Robotics, Systems Engineering (DIBRIS), University of Genova, Genova, Italy
- ScreenNeuroPharm, Sanremo, Italy
| | - Serena Losacco
- Department of Pharmacy (DIFAR), University of Genova, Genova, Italy
| | - Fabio Poggio
- Department of Informatics, Bioengineering, Robotics, Systems Engineering (DIBRIS), University of Genova, Genova, Italy
| | - Roberta Arianna Zerbo
- Department of Pharmacy (DIFAR), Pharmacology and Toxicology Unit, University of Genova, Genova, Italy
| | - Marco Milanese
- Department of Pharmacy (DIFAR), Pharmacology and Toxicology Unit, University of Genova, Genova, Italy
- IRCCS Ospedale Policlinico San Martino, Largo Rosanna Benzi 10, 16132, Genova, Italy
| | - Paolo Massobrio
- Department of Informatics, Bioengineering, Robotics, Systems Engineering (DIBRIS), University of Genova, Genova, Italy.
- National Institute for Nuclear Physics (INFN), Genova, Italy.
| | - Bruno Burlando
- Department of Pharmacy (DIFAR), University of Genova, Genova, Italy
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Tramonti Fantozzi MP, De Cicco V, d’Ascanio P, Cataldo E, De Cicco D, Bruschini L, Barresi M, Faraguna U, Manzoni D. Trigeminal Stimulation and Visuospatial Performance: The Struggle between Chewing and Trigeminal Asymmetries. Biomedicines 2023; 11:2307. [PMID: 37626803 PMCID: PMC10452603 DOI: 10.3390/biomedicines11082307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 07/31/2023] [Accepted: 08/13/2023] [Indexed: 08/27/2023] Open
Abstract
Chewing improves visuospatial performance through locus coeruleus (LC) activation. The effects of bilateral and unilateral mastication were investigated in subjects showing different degrees of asymmetry in masseter electromyographic (EMG) activity during clenching and in pupil size at rest (anisocoria), which is a proxy of LC imbalance. Correlations between performance changes and asymmetry values were found in males, but not in females. Among males, subjects with low asymmetry values (balanced-BAL) were more sensitive than those with high asymmetry values (imbalanced-IMB) to bilateral and unilateral chewing on the side with higher EMG activity (hypertonic). The opposite was true for hypotonic side chewing. BAL subjects were sensitive to unilateral chewing on both sides, while in IMB subjects, hypertonic side chewing did not influence performance in either males or females. Bilateral chewing elicited larger effects in BAL subjects than in IMB subjects, exceeding the values predicted from unilateral chewing in both groups. Finally, pupil size and anisocoria changes elicited by chewing were correlated with asymmetry values, independent of sex. Data confirmed the facilitation of visuospatial performance exerted by chewing. Trigeminal asymmetries modulate the chewing effects, making occlusal rebalancing an appropriate strategy to improve performance.
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Affiliation(s)
- Maria Paola Tramonti Fantozzi
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56123 Pisa, Italy
| | - Vincenzo De Cicco
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56123 Pisa, Italy
| | - Paola d’Ascanio
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56123 Pisa, Italy
| | - Enrico Cataldo
- Department of Physics, University of Pisa, 56127 Pisa, Italy
| | - Davide De Cicco
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56123 Pisa, Italy
| | - Luca Bruschini
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, 56124 Pisa, Italy
| | - Massimo Barresi
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56123 Pisa, Italy
| | - Ugo Faraguna
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56123 Pisa, Italy
- Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, 56128 Pisa, Italy
| | - Diego Manzoni
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56123 Pisa, Italy
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7
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Jeffrey DA, Russell A, Guerrero MB, Fontaine JT, Romero P, Rosehart AC, Dabertrand F. Estrogen regulates myogenic tone in hippocampal arterioles by enhanced basal release of nitric oxide and endothelial SK Ca channel activity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.15.553442. [PMID: 37645715 PMCID: PMC10462022 DOI: 10.1101/2023.08.15.553442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Arteries and arterioles exhibit myogenic tone, a partially constricted state that allows further constriction or dilation in response to moment-to-moment fluctuations in blood pressure. The vascular endothelium that lines the internal surface of all blood vessels controls a wide variety of essential functions, including the contractility of the adjacent smooth muscle cells by providing a tonic vasodilatory influence. Studies conducted on large (pial) arteries on the surface of the brain have shown that estrogen lowers myogenic tone in female mice by enhancing nitric oxide (NO) release from the endothelium, however, whether this difference extends to the intracerebral microcirculation remains ambiguous. The existing incomplete picture of sex differences in cerebrovascular physiology combined with a deficiency in treatments that fully restore cognitive function after cerebrovascular accidents places heavy emphasis on the necessity to investigate myogenic tone regulation in the microcirculation from both male and female mice. We hypothesized that sex-linked hormone regulation of myogenic tone extends its influence on the microcirculation level, and sought to characterize it in isolated arterioles from the hippocampus, a major cognitive brain area. Using diameter measurements both in vivo (acute cranial window vascular diameter) and ex vivo (pressure myography experiments), we measured lower myogenic tone responses in hippocampal arterioles from female than male mice. By using a combined surgical and pharmacological approach, we found myogenic tone in ovariectomized (OVX) female mice matches that of males, as well as in endothelium-denuded arterioles. Interestingly, eNOS inhibition induced a larger constriction in female arterioles but only partially abolished the difference in tone. We identified that the remnant difference was mediated by a higher activity and expression of the small-conductance Ca 2+ -sensitive K + (SK) channels. Collectively, these data indicate that eNOS and SK channels exert greater vasodilatory influence over myogenic tone in female mice at physiological pressures.
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8
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Marinina KS, Bezprozvanny IB, Egorova PA. A chlorzoxazone-folic acid combination improves cognitive affective decline in SCA2-58Q mice. Sci Rep 2023; 13:12588. [PMID: 37537226 PMCID: PMC10400576 DOI: 10.1038/s41598-023-39331-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 07/24/2023] [Indexed: 08/05/2023] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is a polyglutamine disorder caused by a pathological expansion of CAG repeats in ATXN2 gene. SCA2 is accompanied by cerebellar degeneration and progressive motor decline. Cerebellar Purkinje cells (PCs) seem to be primarily affected in this disorder. The majority of the ataxia research is focused on the motor decline observed in ataxic patients and animal models of the disease. However, recent evidence from patients and ataxic mice suggests that SCA2 can also share the symptoms of the cerebellar cognitive affective syndrome. We previously reported that SCA2-58Q PC-specific transgenic mice exhibit anxiolytic behavior, decline in spatial memory, and a depressive-like state. Here we studied the effect of the activation of the small conductance calcium-activated potassium channels (SK channels) by chlorzoxazone (CHZ) combined with the folic acid (FA) on the PC firing and also motor, cognitive and affective symptoms in SCA2-58Q mice. We realized that CHZ-FA combination improved motor and cognitive decline as well as ameliorated mood alterations in SCA2-58Q mice without affecting the firing rate of their cerebellar PCs. Our results support the idea of the combination therapy for both ataxia and non-motor symptoms in ataxic mice without affecting the firing frequency of PCs.
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Affiliation(s)
- Ksenia S Marinina
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
| | - Ilya B Bezprozvanny
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia.
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Polina A Egorova
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia.
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Ma HT, Zhang HC, Zuo ZF, Liu YX. Heterogeneous organization of Locus coeruleus: An intrinsic mechanism for functional complexity. Physiol Behav 2023; 268:114231. [PMID: 37172640 DOI: 10.1016/j.physbeh.2023.114231] [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: 01/30/2023] [Revised: 04/06/2023] [Accepted: 05/09/2023] [Indexed: 05/15/2023]
Abstract
Locus coeruleus (LC) is a small nucleus located deep in the brainstem that contains the majority of central noradrenergic neurons, which provide the primary source of noradrenaline (NA) throughout the entire central nervous system (CNS).The release of neurotransmitter NA is considered to modulate arousal, sensory processing, attention, aversive and adaptive stress responses as well as high-order cognitive function and memory, with the highly ramified axonal arborizations of LC-NA neurons sending wide projections to the targeted brain areas. For over 30 years, LC was thought to be a homogeneous nucleus in structure and function due to the widespread uniform release of NA by LC-NA neurons and simultaneous action in several CNS regions, such as the prefrontal cortex, hippocampus, cerebellum, and spinal cord. However, recent advances in neuroscience tools have revealed that LC is probably not so homogeneous as we previous thought and exhibits heterogeneity in various aspects. Accumulating studies have shown that the functional complexity of LC may be attributed to its heterogeneity in developmental origin, projection patterns, topography distribution, morphology and molecular organization, electrophysiological properties and sex differences. This review will highlight the heterogeneity of LC and its critical role in modulating diverse behavioral outcomes.
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Affiliation(s)
- Hai-Tao Ma
- Department of Neurobiology, School of Basic Medicine, Jinzhou Medical University, Jinzhou, Liaoning, 121000, China; Department of Neurobiology, School of Basic Medicine, Capital Medical University, Beijing, 100069, China.
| | - Hao-Chen Zhang
- Department of Neurobiology, School of Basic Medicine, Capital Medical University, Beijing, 100069, China
| | - Zhong-Fu Zuo
- Department of Human Anatomy, Histology and Embryology, Jinzhou Medical University, Jinzhou, 121000, China
| | - Ying-Xue Liu
- Department of Human Anatomy, Histology and Embryology, Jinzhou Medical University, Jinzhou, 121000, China.
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10
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Davis MJ, Earley S, Li YS, Chien S. Vascular mechanotransduction. Physiol Rev 2023; 103:1247-1421. [PMID: 36603156 PMCID: PMC9942936 DOI: 10.1152/physrev.00053.2021] [Citation(s) in RCA: 50] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 01/07/2023] Open
Abstract
This review aims to survey the current state of mechanotransduction in vascular smooth muscle cells (VSMCs) and endothelial cells (ECs), including their sensing of mechanical stimuli and transduction of mechanical signals that result in the acute functional modulation and longer-term transcriptomic and epigenetic regulation of blood vessels. The mechanosensors discussed include ion channels, plasma membrane-associated structures and receptors, and junction proteins. The mechanosignaling pathways presented include the cytoskeleton, integrins, extracellular matrix, and intracellular signaling molecules. These are followed by discussions on mechanical regulation of transcriptome and epigenetics, relevance of mechanotransduction to health and disease, and interactions between VSMCs and ECs. Throughout this review, we offer suggestions for specific topics that require further understanding. In the closing section on conclusions and perspectives, we summarize what is known and point out the need to treat the vasculature as a system, including not only VSMCs and ECs but also the extracellular matrix and other types of cells such as resident macrophages and pericytes, so that we can fully understand the physiology and pathophysiology of the blood vessel as a whole, thus enhancing the comprehension, diagnosis, treatment, and prevention of vascular diseases.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Scott Earley
- Department of Pharmacology, University of Nevada, Reno, Nevada
| | - Yi-Shuan Li
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
| | - Shu Chien
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
- Department of Medicine, University of California, San Diego, California
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11
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Wang Z, Chen G. Immune regulation in neurovascular units after traumatic brain injury. Neurobiol Dis 2023; 179:106060. [PMID: 36871640 DOI: 10.1016/j.nbd.2023.106060] [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: 12/01/2022] [Revised: 02/19/2023] [Accepted: 02/28/2023] [Indexed: 03/07/2023] Open
Abstract
Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Survivors may experience movement disorders, memory loss, and cognitive deficits. However, there is a lack of understanding of the pathophysiology of TBI-mediated neuroinflammation and neurodegeneration. The immune regulation process of TBI involves changes in the peripheral and central nervous system (CNS) immunity, and intracranial blood vessels are essential communication centers. The neurovascular unit (NVU) is responsible for coupling blood flow with brain activity, and comprises endothelial cells, pericytes, astrocyte end-feet, and vast regulatory nerve terminals. A stable NVU is the basis for normal brain function. The concept of the NVU emphasizes that cell-cell interactions between different types of cells are essential for maintaining brain homeostasis. Previous studies have explored the effects of immune system changes after TBI. The NVU can help us further understand the immune regulation process. Herein, we enumerate the paradoxes of primary immune activation and chronic immunosuppression. We describe the changes in immune cells, cytokines/chemokines, and neuroinflammation after TBI. The post-immunomodulatory changes in NVU components are discussed, and research exploring immune changes in the NVU pattern is also described. Finally, we summarize immune regulation therapies and drugs after TBI. Therapies and drugs that focus on immune regulation have shown great potential for neuroprotection. These findings will help us further understand the pathological processes after TBI.
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Affiliation(s)
- Zongqi Wang
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu Province 215006, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province 215006, China
| | - Gang Chen
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu Province 215006, China; Institute of Stroke Research, Soochow University, Suzhou, Jiangsu Province 215006, China.
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12
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Downs AM, Catavero CM, Kasten MR, McElligott ZA. Tauopathy and alcohol consumption interact to alter locus coeruleus excitatory transmission and excitability in male and female mice. Alcohol 2023; 107:97-107. [PMID: 36150608 DOI: 10.1016/j.alcohol.2022.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 12/23/2022]
Abstract
Alcohol use disorder is a major public health concern in the United States. Recent work has suggested a link between chronic alcohol consumption and the development of tauopathy disorders, such as Alzheimer's disease and frontotemporal dementia. However, relatively little work has investigated changes in neural circuitry involved in both tauopathy disorders and alcohol use disorder. The locus coeruleus (LC) is the major noradrenergic nucleus in the brain and is one of the earliest sites to be affected by tau lesions. The LC is also implicated in the rewarding effects of ethanol and alcohol withdrawal. In this study we assessed effects of long-term ethanol consumption and tauopathy on the physiology of LC neurons. Male and female P301S mice, a humanized transgenic mouse model of tauopathy, underwent 16 weeks of intermittent access to 20% ethanol from 3 to 7 months of age. We observed higher total alcohol consumption in female mice regardless of genotype. Male P301S mice consumed more ethanol and had a greater preference for ethanol than wild-type (WT) males. At the end of the drinking study, LC function was assessed using ex vivo whole cell electrophysiology. We found significant changes in excitatory inputs to the LC due to both ethanol and genotype. We found significantly increased excitability of the LC due to ethanol with greater effects in female P301S mice than in female WT mice. Our study identifies significant changes in the LC due to interactions between tauopathy and long-term ethanol use. These findings could have important implications regarding LC activity and changes in behavior due to both ethanol- and tauopathy-related dementia.
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Affiliation(s)
- Anthony M Downs
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States
| | - Christina M Catavero
- Graduate Program in Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States
| | - Michael R Kasten
- Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States
| | - Zoé A McElligott
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States; Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States; Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States.
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13
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Mechanisms Underlying the Recruitment of Inhibitory Interneurons in Fictive Swimming in Developing Xenopus laevis Tadpoles. J Neurosci 2023; 43:1387-1404. [PMID: 36693757 PMCID: PMC9987577 DOI: 10.1523/jneurosci.0520-22.2022] [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: 03/10/2022] [Revised: 10/27/2022] [Accepted: 12/02/2022] [Indexed: 01/26/2023] Open
Abstract
Developing spinal circuits generate patterned motor outputs while many neurons with high membrane resistances are still maturing. In the spinal cord of hatchling frog tadpoles of unknown sex, we found that the firing reliability in swimming of inhibitory interneurons with commissural and ipsilateral ascending axons was negatively correlated with their cellular membrane resistance. Further analyses showed that neurons with higher resistances had outward rectifying properties, low firing thresholds, and little delay in firing evoked by current injections. Input synaptic currents these neurons received during swimming, either compound, unitary current amplitudes, or unitary synaptic current numbers, were scaled with their membrane resistances, but their own synaptic outputs were correlated with membrane resistances of their postsynaptic partners. Analyses of neuronal dendritic and axonal lengths and their activities in swimming and cellular input resistances did not reveal a clear correlation pattern. Incorporating these electrical and synaptic properties into a computer swimming model produced robust swimming rhythms, whereas randomizing input synaptic strengths led to the breakdown of swimming rhythms, coupled with less synchronized spiking in the inhibitory interneurons. We conclude that the recruitment of these developing interneurons in swimming can be predicted by cellular input resistances, but the order is opposite to the motor-strength-based recruitment scheme depicted by Henneman's size principle. This form of recruitment/integration order in development before the emergence of refined motor control is progressive potentially with neuronal acquisition of mature electrical and synaptic properties, among which the scaling of input synaptic strengths with cellular input resistance plays a critical role.SIGNIFICANCE STATEMENT The mechanisms on how interneurons are recruited to participate in circuit function in developing neuronal systems are rarely investigated. In 2-d-old frog tadpole spinal cord, we found the recruitment of inhibitory interneurons in swimming is inversely correlated with cellular input resistances, opposite to the motor-strength-based recruitment order depicted by Henneman's size principle. Further analyses showed the amplitude of synaptic inputs that neurons received during swimming was inversely correlated with cellular input resistances. Randomizing/reversing the relation between input synaptic strengths and membrane resistances in modeling broke down swimming rhythms. Therefore, the recruitment or integration of these interneurons is conditional on the acquisition of several electrical and synaptic properties including the scaling of input synaptic strengths with cellular input resistances.
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14
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Alaee E, Farahani F, Semnanian S, Azizi H. Prenatal exposure to morphine enhances excitability in locus coeruleus neurons. J Neural Transm (Vienna) 2022; 129:1049-1060. [PMID: 35674919 DOI: 10.1007/s00702-022-02515-3] [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: 03/28/2022] [Accepted: 05/10/2022] [Indexed: 10/18/2022]
Abstract
Opioid abuse during pregnancy may have noteworthy effects on the child's behavioral, emotional and cognitive progression. In this study, we assessed the effect of prenatal exposure to morphine on electrophysiological features of locus coeruleus (LC) noradrenergic neurons which is involved in modulating cognitive performance. Pregnant dams were randomly divided into two groups, that is a prenatal saline treated and prenatal morphine-treated group. To this end, on gestational days 11-18, either morphine or saline (twice daily, s.c.) was administered to pregnant dams. Whole-cell patch-clamp recordings were conducted on LC neurons of male offspring. The evoked firing rate, instantaneous frequency and action potentials half-width, and also input resistance of LC neurons significantly increased in the prenatal morphine group compared to the saline group. Moreover, action potentials decay slope, after hyperpolarization amplitude, rheobase current, and first spike latency were diminished in LC neurons following prenatal exposure to morphine. In addition, resting membrane potential, rise slope, and amplitude of action potentials were not changed by prenatal morphine exposure. Together, the current findings show a significant enhancement in excitability of the LC neurons following prenatal morphine exposure, which may affect the release of norepinephrine to other brain regions and/or cognitive performances of the offspring.
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Affiliation(s)
- Elham Alaee
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Fatemeh Farahani
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Saeed Semnanian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Hossein Azizi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
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15
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Wang J, Wang Y, Du X, Zhang H. Potassium Channel Conductance Is Involved in Phenylephrine-Induced Spontaneous Firing of Serotonergic Neurons in the Dorsal Raphe Nucleus. Front Cell Neurosci 2022; 16:891912. [PMID: 35734219 PMCID: PMC9207280 DOI: 10.3389/fncel.2022.891912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/22/2022] [Indexed: 11/13/2022] Open
Abstract
The serotonergic (5-HT) network from the dorsal raphe nucleus (DRN) of the brain has been demonstrated to regulate cognition, emotion, and behaviors, including learning and the sleep-wake cycle. Dysregulation of the activity of 5-HT neurons in the DRN is thought to play an important role in emotional disorders. The activity of 5-HT neurons is regulated by norepinephrine (NE) released from the projection terminals of noradrenergic input from the locus coeruleus (LC) via activation of the α1-adrenoceptor. However, insight into the molecular mechanism underlying this NE-induced regulation of 5-HT neuron activity is not clear. In this study, using the agonist of α1-adrenoceptor phenylephrine (PE), brain slices, and patch clamp, we found that A-type, Kv7/KCNQ, and calcium-activated low-conductance K+ channels (SK) underlie PE-induced spontaneous firing in DRN 5-HT neurons. Using single-cell PCR and immunofluorescence, we also identified the isoforms of these K+ channel families that might contribute to the NE/PE-induced spontaneous firing of DRN 5-HT neurons.
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Affiliation(s)
- Jing Wang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, China
- Department of Pharmacochemistry, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Yingzi Wang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, China
| | - Xiaona Du
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, China
| | - Hailin Zhang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, China
- *Correspondence: Hailin Zhang,
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16
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Rawal B, Rancic V, Ballanyi K. NMDA Enhances and Glutamate Attenuates Synchrony of Spontaneous Phase-Locked Locus Coeruleus Network Rhythm in Newborn Rat Brain Slices. Brain Sci 2022; 12:brainsci12050651. [PMID: 35625039 PMCID: PMC9140167 DOI: 10.3390/brainsci12050651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/05/2022] [Accepted: 05/12/2022] [Indexed: 01/27/2023] Open
Abstract
Locus coeruleus (LC) neurons are controlled by glutamatergic inputs. Here, we studied in brain slices of neonatal rats NMDA and glutamate effects on phase-locked LC neuron spiking at ~1 Hz summating to ~0.2 s-lasting bell-shaped local field potential (LFP). NMDA: 10 μM accelerated LFP 1.7-fold, whereas 25 and 50 μM, respectively, increased its rate 3.2- and 4.6-fold while merging discrete events into 43 and 56% shorter oscillations. After 4–6 min, LFP oscillations stopped every 6 s for 1 s, resulting in ‘oscillation trains’. A dose of 32 μM depolarized neurons by 8.4 mV to cause 7.2-fold accelerated spiking at reduced jitter and enhanced synchrony with the LFP, as evident from cross-correlation. Glutamate: 25–50 μM made rhythm more irregular and the LFP pattern could transform into 2.7-fold longer-lasting multipeak discharge. In 100 μM, LFP amplitude and duration declined. In 25–50 μM, neurons depolarized by 5 mV to cause 3.7-fold acceleration of spiking that was less synchronized with LFP. Both agents: evoked ‘post-agonist depression’ of LFP that correlated with the amplitude and kinetics of Vm hyperpolarization. The findings show that accelerated spiking during NMDA and glutamate is associated with enhanced or attenuated LC synchrony, respectively, causing distinct LFP pattern transformations. Shaping of LC population discharge dynamics by ionotropic glutamate receptors potentially fine-tunes its influence on brain functions.
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17
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Waselenchuk Q, Ballanyi K. Autocrine Neuromodulation and Network Activity Patterns in the Locus Coeruleus of Newborn Rat Slices. Brain Sci 2022; 12:brainsci12040437. [PMID: 35447969 PMCID: PMC9024645 DOI: 10.3390/brainsci12040437] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/16/2022] [Accepted: 03/19/2022] [Indexed: 02/06/2023] Open
Abstract
Already in newborns, the locus coeruleus (LC) controls multiple brain functions and may have a complex organization as in adults. Our findings in newborn rat brain slices indicate that LC neurons (i) generate at ~1 Hz a ~0.3 s-lasting local field potential (LFP) comprising summated phase-locked single spike discharge, (ii) express intrinsic ‘pacemaker’ or ‘burster’ properties and (iii) receive solely excitatory or initially excitatory−secondary inhibitory inputs. μ-opioid or ɑ2 noradrenaline receptor agonists block LFP rhythm at 100−250 nM whereas slightly lower doses transform its bell-shaped pattern into slower crescendo-shaped multipeak bursts. GABAA and glycine receptors hyperpolarize LC neurons to abolish rhythm which remains though unaffected by blocking them. Rhythm persists also during ionotropic glutamate receptor (iGluR) inhibition whereas <10 mV depolarization during iGluR agonists accelerates spiking to cause subtype-specific fast (spindle-shaped) LFP oscillations. Similar modest neuronal depolarization causing a cytosolic Ca2+ rise occurs (without effect on neighboring astrocytes) during LFP acceleration by CNQX activating a TARP-AMPA-type iGluR complex. In contrast, noradrenaline lowers neuronal Ca2+ baseline via ɑ2 receptors, but evokes an ɑ1 receptor-mediated ‘concentric’ astrocytic Ca2+ wave. In summary, the neonatal LC has a complex (possibly modular) organization to enable discharge pattern transformations that might facilitate discrete actions on target circuits.
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18
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Matschke LA, Komadowski MA, Stöhr A, Lee B, Henrich MT, Griesbach M, Rinné S, Geibl FF, Chiu WH, Koprich JB, Brotchie JM, Kiper AK, Dolga AM, Oertel WH, Decher N. Enhanced firing of locus coeruleus neurons and SK channel dysfunction are conserved in distinct models of prodromal Parkinson's disease. Sci Rep 2022; 12:3180. [PMID: 35210472 PMCID: PMC8873463 DOI: 10.1038/s41598-022-06832-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/07/2022] [Indexed: 12/21/2022] Open
Abstract
Parkinson's disease (PD) is clinically defined by the presence of the cardinal motor symptoms, which are associated with a loss of dopaminergic nigrostriatal neurons in the substantia nigra pars compacta (SNpc). While SNpc neurons serve as the prototypical cell-type to study cellular vulnerability in PD, there is an unmet need to extent our efforts to other neurons at risk. The noradrenergic locus coeruleus (LC) represents one of the first brain structures affected in Parkinson's disease (PD) and plays not only a crucial role for the evolving non-motor symptomatology, but it is also believed to contribute to disease progression by efferent noradrenergic deficiency. Therefore, we sought to characterize the electrophysiological properties of LC neurons in two distinct PD models: (1) in an in vivo mouse model of focal α-synuclein overexpression; and (2) in an in vitro rotenone-induced PD model. Despite the fundamental differences of these two PD models, α-synuclein overexpression as well as rotenone exposure led to an accelerated autonomous pacemaker frequency of LC neurons, accompanied by severe alterations of the afterhyperpolarization amplitude. On the mechanistic side, we suggest that Ca2+-activated K+ (SK) channels are mediators of the increased LC neuronal excitability, as pharmacological activation of these channels is sufficient to prevent increased LC pacemaking and subsequent neuronal loss in the LC following in vitro rotenone exposure. These findings suggest a role of SK channels in PD by linking α-synuclein- and rotenone-induced changes in LC firing rate to SK channel dysfunction.
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Affiliation(s)
- Lina A Matschke
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB, Philipps-University Marburg, 35037, Marburg, Germany.,Clinic for Neurology, Philipps-University Marburg, 35043, Marburg, Germany
| | - Marlene A Komadowski
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB, Philipps-University Marburg, 35037, Marburg, Germany
| | - Annette Stöhr
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB, Philipps-University Marburg, 35037, Marburg, Germany
| | - Bolam Lee
- Clinic for Neurology, Philipps-University Marburg, 35043, Marburg, Germany
| | - Martin T Henrich
- Clinic for Neurology, Philipps-University Marburg, 35043, Marburg, Germany
| | - Markus Griesbach
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB, Philipps-University Marburg, 35037, Marburg, Germany
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB, Philipps-University Marburg, 35037, Marburg, Germany
| | - Fanni F Geibl
- Clinic for Neurology, Philipps-University Marburg, 35043, Marburg, Germany
| | - Wei-Hua Chiu
- Clinic for Neurology, Philipps-University Marburg, 35043, Marburg, Germany
| | - James B Koprich
- Krembil Research Institute, Toronto Western Hospital, University Health Network, 8KD402, Toronto, ON, M5T 2S8, Canada
| | - Jonathan M Brotchie
- Krembil Research Institute, Toronto Western Hospital, University Health Network, 8KD402, Toronto, ON, M5T 2S8, Canada
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB, Philipps-University Marburg, 35037, Marburg, Germany
| | - Amalia M Dolga
- Faculty of Science and Engineering, Groningen Research Institute of Pharmacy, Department of Molecular Pharmacology, University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Wolfgang H Oertel
- Clinic for Neurology, Philipps-University Marburg, 35043, Marburg, Germany.,Hertie Senior Research Professor of the Charitable Hertie Foundation, 60323, Frankfurt am Main, Germany
| | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB, Philipps-University Marburg, 35037, Marburg, Germany.
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19
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Dwivedi D, Bhalla US. Physiology and Therapeutic Potential of SK, H, and M Medium AfterHyperPolarization Ion Channels. Front Mol Neurosci 2021; 14:658435. [PMID: 34149352 PMCID: PMC8209339 DOI: 10.3389/fnmol.2021.658435] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/13/2021] [Indexed: 12/19/2022] Open
Abstract
SK, HCN, and M channels are medium afterhyperpolarization (mAHP)-mediating ion channels. The three channels co-express in various brain regions, and their collective action strongly influences cellular excitability. However, significant diversity exists in the expression of channel isoforms in distinct brain regions and various subcellular compartments, which contributes to an equally diverse set of specific neuronal functions. The current review emphasizes the collective behavior of the three classes of mAHP channels and discusses how these channels function together although they play specialized roles. We discuss the biophysical properties of these channels, signaling pathways that influence the activity of the three mAHP channels, various chemical modulators that alter channel activity and their therapeutic potential in treating various neurological anomalies. Additionally, we discuss the role of mAHP channels in the pathophysiology of various neurological diseases and how their modulation can alleviate some of the symptoms.
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Affiliation(s)
- Deepanjali Dwivedi
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bengaluru, India.,Department of Neurobiology, Harvard Medical School, Boston, MA, United States.,Stanley Center at the Broad, Cambridge, MA, United States
| | - Upinder S Bhalla
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bengaluru, India
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20
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Farahani F, Azizi H, Janahmadi M, Seutin V, Semnanian S. Formalin-induced inflammatory pain increases excitability in locus coeruleus neurons. Brain Res Bull 2021; 172:52-60. [PMID: 33836239 DOI: 10.1016/j.brainresbull.2021.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 03/30/2021] [Accepted: 04/03/2021] [Indexed: 11/19/2022]
Abstract
Chronic pain is recognized as an important problem in communities. The locus coeruleus (LC) with extensive ascending and descending projections has a critical role in modulating pain. Some studies indicate how the locus coeruleus-noradrenaline system can remain more active after nociceptive stimulation. In the present study, we examined whether formalin-induced inflammatory pain may affect the electrophysiological properties of LC neurons after 24 h. Inflammatory pain was induced by a subcutaneous injection of 2% formalin (10 μL) into the hind paw of 2-3 week-old male Wistar rats. After 24 h, horizontal slices of brain stem containing the locus coeruleus were prepared and whole-cell patch-clamp recordings were carried out on LC neurons. Findings revealed that LC neurons from formalin injected rats had a significant enhancement in firing rate, half-width and instantaneous frequency of action potentials, but their resting membrane potential, input resistance and afterhyperpolarization amplitude almost remained unchanged. In addition, action potential peak amplitude, maximum rise slope, maximum decay slope, first spike latency and rheobase current significantly decreased in LC neurons obtained from formalin-treated rats. Here, for the first time, we demonstrate that inflammatory pain after 24 h induces hyperexcitability in LC neurons, which in turn may result in changes in noradrenaline release and pain processing.
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Affiliation(s)
- Fatemeh Farahani
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Hossein Azizi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Mahyar Janahmadi
- Neuroscience Research Center and Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Vincent Seutin
- Neurophysiology Unit, GIGA Neurosciences, University of Liege, Liege, Belgium
| | - Saeed Semnanian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
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21
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Borodovitsyna O, Duffy BC, Pickering AE, Chandler DJ. Anatomically and functionally distinct locus coeruleus efferents mediate opposing effects on anxiety-like behavior. Neurobiol Stress 2020; 13:100284. [PMID: 33344735 PMCID: PMC7739179 DOI: 10.1016/j.ynstr.2020.100284] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/19/2020] [Accepted: 12/02/2020] [Indexed: 01/08/2023] Open
Abstract
The locus coeruleus (LC) is a critical node in the stress response, and its activation has been shown to promote hypervigilance and anxiety-like behavior. This noradrenergic nucleus has historically been considered homogeneous with highly divergent neurons that operate en masse to collectively affect central nervous system function and behavioral state. However, in recent years, LC has been identified as a heterogeneous structure whose neurons innervate discrete terminal fields and contribute to distinct aspects of behavior. We have previously shown that in late adolescent male rats, an acute traumatic stressor, simultaneous physical restraint and exposure to predator odor, preferentially induces c-Fos expression in a subset of dorsal LC neurons and persistently increases anxiety-like behavior. To investigate how these neurons respond to and contribute to the behavioral response to stress, we used a combination of retrograde tracing, whole-cell patch clamp electrophysiology, and chemogenetics. Here we show that LC neurons innervating the central nucleus of the amygdala (CeA) and medial prefrontal cortex (mPFC) undergo distinct electrophysiological changes in response to stressor exposure and have opposing roles in mediating anxiety-like behavior. While neurons innervating CeA become more excitable in response to stress and promote anxiety-like behavior, those innervating mPFC become less excitable and appear to promote exploration. These findings show that LC neurons innervating distinct terminal fields have unique physiological responses to particular stimuli. Furthermore, these observations advance the understanding of the LC as a complex and heterogeneous structure whose neurons maintain unique roles in various forms of behavior. Locus coeruleus-central amygdala projections are hyperactive one week after stress. Locus coeruleus-prefrontal cortex projections are hypoactive one week after stress. Chemogenetic manipulation of each pathway distinctly affects anxiety-like behavior.
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Key Words
- AHP, afterhyperpolarization
- Anxiety-like behavior
- CRF, corticotropin releasing factor
- CeA, central nucleus of the amygdala
- Central nucleus of amygdala
- EPM, elevated plus maze
- LC, locus coeruleus
- Locus coeruleus
- Medial prefrontal cortex
- NE, norepinephrine
- OFT, open field test
- PBS, phosphate buffered saline
- Stress
- TMT, 2,4,5-trimethylthiazole
- aCSF, artificial cerebrospinal fluid
- mPFC, medial prefrontal cortex
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Affiliation(s)
- Olga Borodovitsyna
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, 42 E. Laurel Road, Stratford, NJ, 08084, USA
| | - Brenna C Duffy
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, 42 E. Laurel Road, Stratford, NJ, 08084, USA
| | - Anthony E Pickering
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS81TD, UK
| | - Daniel J Chandler
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, 42 E. Laurel Road, Stratford, NJ, 08084, USA
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22
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Sun J, Liu Y, Baudry M, Bi X. SK2 channel regulation of neuronal excitability, synaptic transmission, and brain rhythmic activity in health and diseases. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2020; 1867:118834. [PMID: 32860835 PMCID: PMC7541745 DOI: 10.1016/j.bbamcr.2020.118834] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 08/13/2020] [Accepted: 08/19/2020] [Indexed: 11/20/2022]
Abstract
Small conductance calcium-activated potassium channels (SKs) are solely activated by intracellular Ca2+ and their activation leads to potassium efflux, thereby repolarizing/hyperpolarizing membrane potential. Thus, these channels play a critical role in synaptic transmission, and consequently in information transmission along the neuronal circuits expressing them. SKs are widely but not homogeneously distributed in the central nervous system (CNS). Activation of SKs requires submicromolar cytoplasmic Ca2+ concentrations, which are reached following either Ca2+ release from intracellular Ca2+ stores or influx through Ca2+ permeable membrane channels. Both Ca2+ sensitivity and synaptic levels of SKs are regulated by protein kinases and phosphatases, and degradation pathways. SKs in turn control the activity of multiple Ca2+ channels. They are therefore critically involved in coordinating diverse Ca2+ signaling pathways and controlling Ca2+ signal amplitude and duration. This review highlights recent advances in our understanding of the regulation of SK2 channels and of their roles in normal brain functions, including synaptic plasticity, learning and memory, and rhythmic activities. It will also discuss how alterations in their expression and regulation might contribute to various brain disorders such as Angelman Syndrome, Alzheimer's disease and Parkinson's disease.
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Affiliation(s)
- Jiandong Sun
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA 91766, United States of America; Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766, United States of America
| | - Yan Liu
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA 91766, United States of America; Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766, United States of America
| | - Michel Baudry
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA 91766, United States of America; Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766, United States of America
| | - Xiaoning Bi
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA 91766, United States of America; Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766, United States of America.
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23
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Janitzky K. Impaired Phasic Discharge of Locus Coeruleus Neurons Based on Persistent High Tonic Discharge-A New Hypothesis With Potential Implications for Neurodegenerative Diseases. Front Neurol 2020; 11:371. [PMID: 32477246 PMCID: PMC7235306 DOI: 10.3389/fneur.2020.00371] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/14/2020] [Indexed: 12/21/2022] Open
Abstract
The locus coeruleus (LC) is a small brainstem nucleus with widely distributed noradrenergic projections to the whole brain, and loss of LC neurons is a prominent feature of age-related neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). This article discusses the hypothesis that in early stages of neurodegenerative diseases, the discharge mode of LC neurons could be changed to a persistent high tonic discharge, which in turn might impair phasic discharge. Since phasic discharge of LC neurons is required for the release of high amounts of norepinephrine (NE) in the brain to promote anti-inflammatory and neuroprotective effects, persistent high tonic discharge of LC neurons could be a key factor in the progression of neurodegenerative diseases. Transcutaneous vagal stimulation (t-VNS), a non-invasive technique that potentially increases phasic discharge of LC neurons, could therefore provide a non-pharmacological treatment approach in specific disease stages. This article focuses on LC vulnerability in neurodegenerative diseases, discusses the hypothesis that a persistent high tonic discharge of LC neurons might affect neurodegenerative processes, and finally reflects on t-VNS as a potentially useful clinical tool in specific stages of AD and PD.
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Affiliation(s)
- Kathrin Janitzky
- Department of Neurology, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
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24
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Kawano H, Mitchell SB, Koh JY, Goodman KM, Harata NC. Calcium-induced calcium release in noradrenergic neurons of the locus coeruleus. Brain Res 2020; 1729:146627. [PMID: 31883849 DOI: 10.1016/j.brainres.2019.146627] [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: 11/25/2019] [Revised: 12/19/2019] [Accepted: 12/24/2019] [Indexed: 12/11/2022]
Abstract
The locus coeruleus (LC) is a nucleus within the brainstem that consists of norepinephrine-releasing neurons. It is involved in broad processes including cognitive and emotional functions. Understanding the mechanisms that control the excitability of LC neurons is important because they innervate widespread brain regions. One of the key regulators is cytosolic calcium concentration ([Ca2+]c), the increases in which can be amplified by calcium-induced calcium release (CICR) from intracellular calcium stores. Although the electrical activities of LC neurons are regulated by changes in [Ca2+]c, the extent of CICR involvement in this regulation has remained unclear. Here we show that CICR hyperpolarizes acutely dissociated LC neurons of the rat and demonstrate the underlying pathway. When CICR was activated by extracellular application of 10 mM caffeine, LC neurons were hyperpolarized in the current-clamp mode of patch-clamp recording, and the majority of neurons showed an outward current in the voltage-clamp mode. This outward current was accompanied by increased membrane conductance, and its reversal potential was close to the K+ equilibrium potential, indicating that it is mediated by opening of K+ channels. The outward current was generated in the absence of extracellular calcium and was blocked when the calcium stores were inhibited by applying ryanodine. Pharmacological blockers indicated that it was mediated by Ca2+-activated K+ channels of the non-small conductance type. The application of caffeine increased [Ca2+]c, as visualized by fluorescence microscopy. These findings show CICR suppresses LC neuronal activity, and indicate its dynamic role in modulating the LC-mediated noradrenergic tone in the brain.
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Affiliation(s)
- Hiroyuki Kawano
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Sara B Mitchell
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Jin-Young Koh
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology-Head and Neck Surgery, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Biomedical Engineering, University of Iowa College of Engineering, Iowa City, IA, USA
| | - Kirsty M Goodman
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Biology & Biochemistry, University of Bath, Bath, UK
| | - N Charles Harata
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA.
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Prosdocimi E, Checchetto V, Leanza L. Targeting the Mitochondrial Potassium Channel Kv1.3 to Kill Cancer Cells: Drugs, Strategies, and New Perspectives. SLAS DISCOVERY 2019; 24:882-892. [PMID: 31373829 DOI: 10.1177/2472555219864894] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cancer is the consequence of aberrations in cell growth or cell death. In this scenario, mitochondria and ion channels play a critical role in regard to cell proliferation, malignant angiogenesis, migration, and metastasis. In this review, we focus on Kv1.3 and specifically on mitoKv1.3, which showed an aberrant expression in cancer cells compared with healthy tissues and which is involved in the apoptotic pathway. In recent years, mitoKv1.3 has become an oncological target since its pharmacological modulation has been demonstrated to reduce tumor growth and progression both in vitro and in vivo using preclinical mouse models of different types of tumors.
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Affiliation(s)
| | | | - Luigi Leanza
- Department of Biology, University of Padova, Padova, Italy
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26
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Exploration of Ion Channels in the Clitoris: a Review. CURRENT SEXUAL HEALTH REPORTS 2019. [DOI: 10.1007/s11930-019-00206-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Tolouei SEL, Palozi RAC, Tirloni CAS, Marques AAM, Schaedler MI, Guarnier LP, Silva AO, de Almeida VP, Manfron Budel J, Souza RIC, Dos Santos AC, Silva DB, Lourenço ELB, Dalsenter PR, Gasparotto Junior A. Ethnopharmacological approaches to Talinum paniculatum (Jacq.) Gaertn. - Exploring cardiorenal effects from the Brazilian Cerrado. JOURNAL OF ETHNOPHARMACOLOGY 2019; 238:111873. [PMID: 30986519 DOI: 10.1016/j.jep.2019.111873] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 11/05/2018] [Accepted: 04/09/2019] [Indexed: 06/09/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Talinum paniculatum (Jacq.) Gaertn. (Talinaceae), popularly known as "major gomes" and "erva gorda", is a non-conventional food plant extensively distributed throughout the Brazilian territory. In Brazilian folk medicine, this species is used as aphrodisiac, to treat gastrointestinal problems, and as a cardioprotective agent. However, there are no reports in the literature proving its cardiovascular effects. AIM To perform a whole-ethnopharmacological investigation of the cardiorenal properties of the ethanol soluble fraction from T. paniculatum (ESTP) in Wistar rats. MATERIAL AND METHODS First, plant samples were collected, properly identified and a morpho-anatomical characterization was carried out to provide quality control parameters. Then, ESTP was obtained and its chemical profile was determined by LC-DAD-MS. In addition, an acute toxicity assay was conducted in female Wistar rats in order to observe any toxic effects after one single administration. Finally, the diuretic and hypotensive potential of ESTP (30, 100 and 300 mg/kg) were investigated in male rats followed by the evaluation of its possible effects on peripheral vascular resistance. RESULTS Chemical compounds identified from ESTP were chlorogenic acids, amino acids, nucleosides, O-glycosylated flavones and organic acids. No signs of toxicity as well as no changes in urine volume or electrolyte elimination were observed after ESTP acute treatment. On the other hand, prolonged treatment with all doses of ESTP significantly increased urine volume and electrolyte excretion (Na+, K+ and Cl-) without affecting blood pressure or heart rate. Apparently, these effects are involved with the activation of the small conductance calcium-activated potassium channels contributing to the increase of renal blood flow and glomerular filtration rate. CONCLUSION Data presented show important information about the ethnomedicinal properties of T. paniculatum. In addition, the study presents the ESTP as a possible herbal medicine, especially when a sustained diuretic effect is required.
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Affiliation(s)
| | - Rhanany Alan Calloi Palozi
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Cleide Adriane Signor Tirloni
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Aline Aparecida Macedo Marques
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Maysa Isernhagen Schaedler
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Lucas Pires Guarnier
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Aniely Oliveira Silva
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Valter Paes de Almeida
- Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Estadual de Ponta Grossa, Ponta Grossa, PR, Brazil
| | - Jane Manfron Budel
- Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Estadual de Ponta Grossa, Ponta Grossa, PR, Brazil
| | - Roosevelt Isaias Carvalho Souza
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Ariany Carvalho Dos Santos
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil
| | - Denise Brentan Silva
- Laboratório de Produtos Naturais e Espectrometria de Massas (LaPNEM), Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição (FACFAN), Universidade Federal do Mato Grosso do Sul, Campo Grande, MS, Brazil
| | | | - Paulo Roberto Dalsenter
- Laboratório de Toxicologia Reprodutiva, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Arquimedes Gasparotto Junior
- Laboratório de Eletrofisiologia e Farmacologia Cardiovascular (LEFaC), Faculdade de Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, MS, Brazil.
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Cui ED, Strowbridge BW. Selective attenuation of Ether-a-go-go related K + currents by endogenous acetylcholine reduces spike-frequency adaptation and network correlation. eLife 2019; 8:e44954. [PMID: 31032798 PMCID: PMC6488300 DOI: 10.7554/elife.44954] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 04/11/2019] [Indexed: 12/21/2022] Open
Abstract
Most neurons do not simply convert inputs into firing rates. Instead, moment-to-moment firing rates reflect interactions between synaptic inputs and intrinsic currents. Few studies investigated how intrinsic currents function together to modulate output discharges and which of the currents attenuated by synthetic cholinergic ligands are actually modulated by endogenous acetylcholine (ACh). In this study we optogenetically stimulated cholinergic fibers in rat neocortex and find that ACh enhances excitability by reducing Ether-à-go-go Related Gene (ERG) K+ current. We find ERG mediates the late phase of spike-frequency adaptation in pyramidal cells and is recruited later than both SK and M currents. Attenuation of ERG during coincident depolarization and ACh release leads to reduced late phase spike-frequency adaptation and persistent firing. In neuronal ensembles, attenuating ERG enhanced signal-to-noise ratios and reduced signal correlation, suggesting that these two hallmarks of cholinergic function in vivo may result from modulation of intrinsic properties.
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Affiliation(s)
- Edward D Cui
- Department of NeurosciencesCase Western Reserve UniversityClevelandUnited States
| | - Ben W Strowbridge
- Department of NeurosciencesCase Western Reserve UniversityClevelandUnited States
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29
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Key J, Mueller AK, Gispert S, Matschke L, Wittig I, Corti O, Münch C, Decher N, Auburger G. Ubiquitylome profiling of Parkin-null brain reveals dysregulation of calcium homeostasis factors ATP1A2, Hippocalcin and GNA11, reflected by altered firing of noradrenergic neurons. Neurobiol Dis 2019; 127:114-130. [PMID: 30763678 DOI: 10.1016/j.nbd.2019.02.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 12/05/2018] [Accepted: 02/08/2019] [Indexed: 02/06/2023] Open
Abstract
Parkinson's disease (PD) is the second most frequent neurodegenerative disorder in the old population. Among its monogenic variants, a frequent cause is a mutation in the Parkin gene (Prkn). Deficient function of Parkin triggers ubiquitous mitochondrial dysfunction and inflammation in the brain, but it remains unclear how selective neural circuits become vulnerable and finally undergo atrophy. We attempted to go beyond previous work, mostly done in peripheral tumor cells, which identified protein targets of Parkin activity, an ubiquitin E3 ligase. Thus, we now used aged Parkin-knockout (KO) mouse brain for a global quantification of ubiquitylated peptides by mass spectrometry (MS). This approach confirmed the most abundant substrate to be VDAC3, a mitochondrial outer membrane porin that modulates calcium flux, while uncovering also >3-fold dysregulations for neuron-specific factors. Ubiquitylation decreases were prominent for Hippocalcin (HPCA), Calmodulin (CALM1/CALML3), Pyruvate Kinase (PKM2), sodium/potassium-transporting ATPases (ATP1A1/2/3/4), the Rab27A-GTPase activating protein alpha (TBC1D10A) and an ubiquitin ligase adapter (DDB1), while strong increases occurred for calcium transporter ATP2C1 and G-protein subunits G(i)/G(o)/G(Tr). Quantitative immunoblots validated elevated abundance for the electrogenic pump ATP1A2, for HPCA as neuron-specific calcium sensor, which stimulates guanylate cyclases and modifies axonal slow afterhyperpolarization (sAHP), and for the calcium-sensing G-protein GNA11. We assessed if compensatory molecular regulations become insufficient over time, leading to functional deficits. Patch clamp experiments in acute Parkin-KO brain slices indeed revealed alterations of the electrophysiological properties in aged noradrenergic locus coeruleus (LC) neurons. LC neurons of aged Parkin-KO brain showed an acceleration of the spontaneous pacemaker frequency, a reduction in sAHP and shortening of action potential duration, without modulation of KCNQ potassium currents. These findings indicate altered calcium-dependent excitability in a PARK2 model of PD, mediated by diminished turnover of potential Parkin targets such as ATP1A2 and HPCA. The data also identified further novel Parkin substrate candidates like SIRT2, OTUD7B and CUL5. Our elucidation of neuron-specific mechanisms of PD pathogenesis helps to explain the known exceptional susceptibility of noradrenergic and dopaminergic projections to alterations of calcium homeostasis and its mitochondrial buffering.
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Affiliation(s)
- J Key
- Exp. Neurology, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - A K Mueller
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB; Clinic for Neurology, Philipps-University Marburg, 35037 Marburg, Germany
| | - S Gispert
- Exp. Neurology, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - L Matschke
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB; Clinic for Neurology, Philipps-University Marburg, 35037 Marburg, Germany
| | - I Wittig
- Functional Proteomics, SFB 815 Core Unit, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - O Corti
- Institut du Cerveau et de la Moelle épinière, ICM, Paris, F-75013, France; Inserm, U1127, Paris, F-75013, France; CNRS, UMR 7225, Paris, F-75013, France; Sorbonne Universités, Paris, F-75013, France
| | - C Münch
- Institute of Biochemistry II, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - N Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB; Clinic for Neurology, Philipps-University Marburg, 35037 Marburg, Germany.
| | - G Auburger
- Exp. Neurology, Goethe University Medical School, 60590 Frankfurt am Main, Germany.
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TARP mediation of accelerated and more regular locus coeruleus network bursting in neonatal rat brain slices. Neuropharmacology 2019; 148:169-177. [PMID: 30629989 DOI: 10.1016/j.neuropharm.2019.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 01/05/2019] [Accepted: 01/07/2019] [Indexed: 12/31/2022]
Abstract
Transmembrane AMPA receptor (AMPAR) regulatory proteins (TARP) increase neuronal excitability. However, it is unknown how TARP affect rhythmic neural network activity. Here we studied TARP effects on local field potential (LFP) bursting, membrane potential and cytosolic Ca2+ (Cai) in locus coeruleus neurons of newborn rat brain slices. LFP bursting was not affected by the unselective competitive ionotropic glutamate receptor antagonist kynurenic acid (2.5 mM). TARP-AMPAR complex activation with 25 μM CNQX accelerated LFP rhythm 2.2-fold and decreased its irregularity score from 63 to 9. Neuronal spiking was correspondingly 2.3-fold accelerated in association with a 2-5 mV depolarization and a modest Cai rise whereas Cai was unchanged in neighboring astrocytes. After blocking rhythmic activities with tetrodotoxin (1 μM), CNQX caused a 5-8 mV depolarization and also the Cai rise persisted. In tetrodotoxin, both responses were abolished by the non-competitive AMPAR antagonist GYKI 53655 (25 μM) which also reversed stimulatory CNQX effects in control solution. The CNQX-evoked Cai rise was blocked by the L-type voltage-activated Ca2+ channel inhibitor nifedipine (100 μM). The findings show that ionotropic glutamate receptor-independent neonatal locus coeruleus network bursting is accelerated and becomes more regular by activating a TARP-AMPAR complex. The associated depolarization-evoked L-type Ca2+ channel-mediated neuronal Cai rise may be pivotal to regulate locus coeruleus activity in cooperation with SK-type K+ channels. In summary, this is the first demonstration of TARP-mediated stimulation of neural network bursting. We hypothesize that TARP-AMPAR stimulation of rhythmic locus coeruleus output serves to fine-tune its control of multiple brain functions thus comprising a target for drug discovery.
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31
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Leanza L, Checchetto V, Biasutto L, Rossa A, Costa R, Bachmann M, Zoratti M, Szabo I. Pharmacological modulation of mitochondrial ion channels. Br J Pharmacol 2019; 176:4258-4283. [PMID: 30440086 DOI: 10.1111/bph.14544] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 10/15/2018] [Accepted: 10/22/2018] [Indexed: 12/17/2022] Open
Abstract
The field of mitochondrial ion channels has undergone a rapid development during the last three decades, due to the molecular identification of some of the channels residing in the outer and inner membranes. Relevant information about the function of these channels in physiological and pathological settings was gained thanks to genetic models for a few, mitochondria-specific channels. However, many ion channels have multiple localizations within the cell, hampering a clear-cut determination of their function by pharmacological means. The present review summarizes our current knowledge about the ins and outs of mitochondrial ion channels, with special focus on the channels that have received much attention in recent years, namely, the voltage-dependent anion channels, the permeability transition pore (also called mitochondrial megachannel), the mitochondrial calcium uniporter and some of the inner membrane-located potassium channels. In addition, possible strategies to overcome the difficulties of specifically targeting mitochondrial channels versus their counterparts active in other membranes are discussed, as well as the possibilities of modulating channel function by small peptides that compete for binding with protein interacting partners. Altogether, these promising tools along with large-scale chemical screenings set up to identify new, specific channel modulators will hopefully allow us to pinpoint the actual function of most mitochondrial ion channels in the near future and to pharmacologically affect important pathologies in which they are involved, such as neurodegeneration, ischaemic damage and cancer. LINKED ARTICLES: This article is part of a themed section on Mitochondrial Pharmacology: Featured Mechanisms and Approaches for Therapy Translation. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.22/issuetoc.
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Affiliation(s)
- Luigi Leanza
- Department of Biology, University of Padova, Padova, Italy
| | | | - Lucia Biasutto
- CNR Institute of Neurosciences, Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Andrea Rossa
- Department of Chemical Sciences, University of Padova, Padova, Italy
| | - Roberto Costa
- Department of Biology, University of Padova, Padova, Italy
| | | | - Mario Zoratti
- CNR Institute of Neurosciences, Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Ildiko Szabo
- Department of Biology, University of Padova, Padova, Italy.,CNR Institute of Neurosciences, Department of Biomedical Sciences, University of Padova, Padova, Italy
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Briggs C, Bowes SC, Semba K, Hirasawa M. Sleep deprivation-induced pre- and postsynaptic modulation of orexin neurons. Neuropharmacology 2018; 154:50-60. [PMID: 30586566 DOI: 10.1016/j.neuropharm.2018.12.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 12/20/2018] [Accepted: 12/21/2018] [Indexed: 10/27/2022]
Abstract
Sleep/wake states are controlled by sleep- and wake-promoting systems, and transitions between states are thought to be regulated by their reciprocal inhibition and homeostatic sleep need. Orexin neurons are known to promote wake maintenance and stabilize the sleep/wake switch. Thus, we asked whether orexin neurons are modulated by homeostatic sleep need. Rats were sleep deprived or left undisturbed to rest for 6 h, then acute brain slices were generated for patch clamp recordings. We found that sleep deprivation increased firing and reduced spike frequency adaptation in response to excitatory drive in orexin neurons. These changes were specific to D-type orexin neurons which, unlike H-type orexin neurons, lack A-type current. In D-type orexin neurons, sleep deprivation decreased afterhyperpolarizing potential, which was associated with increased gain, measured as the slope of the input-output relationship. These effects were mimicked by inhibition of SK channels. Furthermore, sleep deprivation resulted in presynaptic inhibition of excitatory inputs to both D-type and H-type orexin neurons, which preferentially affected sparse synaptic inputs while sparing high frequency synaptic activities. Taken together, our results indicate that sleep deprivation modulates the gain control and synaptic gating in orexin neurons. These pre-and postsynaptic changes would tune orexin neurons to strong wake-promoting excitatory signals, while dampening weak synaptic inputs to allow transition to sleep in the absence of such strong signals. These mechanisms are consistent with a role of orexin neurons not only as a key state stabilizer, but also as a homeostatic wake integrator in the sleep/wake switch. This article is part of the Special Issue entitled 'Hypothalamic Control of Homeostasis'.
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Affiliation(s)
- Chantalle Briggs
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, NL, A1B 3V6, Canada; Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, NS, B3H 4R2, Canada
| | - Sherri C Bowes
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, NL, A1B 3V6, Canada
| | - Kazue Semba
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, NS, B3H 4R2, Canada; Department of Psychiatry, Faculty of Medicine, Dalhousie University, 5909 Veterans' Memorial Lane, Halifax, NS, B3H 2E2, Canada; Department of Psychology and Neuroscience, Faculty of Science, Dalhousie University, 1355 Oxford Street, Halifax, NS, B3H 4R2, Canada
| | - Michiru Hirasawa
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, 300 Prince Philip Drive, St. John's, NL, A1B 3V6, Canada.
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Farashi S, Sasanpour P, Rafii-Tabar H. Investigation of the role of ion channels in human pancreatic β-cell hubs: A mathematical modeling study. Comput Biol Med 2018; 97:50-62. [PMID: 29705290 DOI: 10.1016/j.compbiomed.2018.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 04/09/2018] [Accepted: 04/09/2018] [Indexed: 12/27/2022]
Abstract
In many cellular networks, the structure of the network follows a scale-free organization, where a limited number of cells are strongly coupled to other cells. These cells are called hub cells and their critical roles are well accepted. Despite their importance, there have been only a few studies investigating the characteristic features of these cells. In this paper, a computational approach is proposed to study the possible role of different ion channels in distinguishing between the hub and non-hub cells. The results show that the P/Q-type and T-type calcium channels may have an especial role in the β-cell hubs because the high-level expressions of these channels make a pancreatic β-cell more potent to force other coupled cells to follow it. In addition, in order to consider the variation of the coupling strength with voltage, a novel mathematical model is proposed for the gap junction coupling between the pancreatic β-cells. The proposed approach is validated based on the data from the literature.
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Affiliation(s)
- Sajjad Farashi
- Department of Medical Physics & Biomedical Engineering, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Pezhman Sasanpour
- Department of Medical Physics & Biomedical Engineering, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Computational Nano-Bioelectromagnetics Research Group, School of Nano-Science, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran.
| | - Hashem Rafii-Tabar
- Department of Medical Physics & Biomedical Engineering, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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