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Qi ZX, Yan Q, Fan XJ, Peng JY, Zhu HX, Jiang YM, Chen L, Zhuang QX. Role of HCN channels in the functions of basal ganglia and Parkinson's disease. Cell Mol Life Sci 2024; 81:135. [PMID: 38478096 PMCID: PMC10937777 DOI: 10.1007/s00018-024-05163-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 01/19/2024] [Accepted: 02/06/2024] [Indexed: 03/17/2024]
Abstract
Parkinson's disease (PD) is a motor disorder resulting from dopaminergic neuron degeneration in the substantia nigra caused by age, genetics, and environment. The disease severely impacts a patient's quality of life and can even be life-threatening. The hyperpolarization-activated cyclic nucleotide-gated (HCN) channel is a member of the HCN1-4 gene family and is widely expressed in basal ganglia nuclei. The hyperpolarization-activated current mediated by the HCN channel has a distinct impact on neuronal excitability and rhythmic activity associated with PD pathogenesis, as it affects the firing activity, including both firing rate and firing pattern, of neurons in the basal ganglia nuclei. This review aims to comprehensively understand the characteristics of HCN channels by summarizing their regulatory role in neuronal firing activity of the basal ganglia nuclei. Furthermore, the distribution and characteristics of HCN channels in each nucleus of the basal ganglia group and their effect on PD symptoms through modulating neuronal electrical activity are discussed. Since the roles of the substantia nigra pars compacta and reticulata, as well as globus pallidus externus and internus, are distinct in the basal ganglia circuit, they are individually described. Lastly, this investigation briefly highlights that the HCN channel expressed on microglia plays a role in the pathological process of PD by affecting the neuroinflammatory response.
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Affiliation(s)
- Zeng-Xin Qi
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, 200030, China
- National Center for Neurological Disorders, Shanghai, 200030, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, 200030, China
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200030, China
| | - Qi Yan
- Department of Physiology, School of Medicine, Nantong University, 19 Qixiu Road, Nantong, 226001, Jiangsu, China
| | - Xiu-Juan Fan
- Department of Physiology, School of Medicine, Nantong University, 19 Qixiu Road, Nantong, 226001, Jiangsu, China
| | - Jian-Ya Peng
- Department of Physiology, School of Medicine, Nantong University, 19 Qixiu Road, Nantong, 226001, Jiangsu, China
| | - Hui-Xian Zhu
- Department of Physiology, School of Medicine, Nantong University, 19 Qixiu Road, Nantong, 226001, Jiangsu, China
| | - Yi-Miao Jiang
- Department of Physiology, School of Medicine, Nantong University, 19 Qixiu Road, Nantong, 226001, Jiangsu, China
| | - Liang Chen
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, 200030, China.
- National Center for Neurological Disorders, Shanghai, 200030, China.
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, 200030, China.
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200030, China.
| | - Qian-Xing Zhuang
- Department of Physiology, School of Medicine, Nantong University, 19 Qixiu Road, Nantong, 226001, Jiangsu, China.
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Cronin SJF, Yu W, Hale A, Licht-Mayer S, Crabtree MJ, Korecka JA, Tretiakov EO, Sealey-Cardona M, Somlyay M, Onji M, An M, Fox JD, Turnes BL, Gomez-Diaz C, da Luz Scheffer D, Cikes D, Nagy V, Weidinger A, Wolf A, Reither H, Chabloz A, Kavirayani A, Rao S, Andrews N, Latremoliere A, Costigan M, Douglas G, Freitas FC, Pifl C, Walz R, Konrat R, Mahad DJ, Koslov AV, Latini A, Isacson O, Harkany T, Hallett PJ, Bagby S, Woolf CJ, Channon KM, Je HS, Penninger JM. Crucial neuroprotective roles of the metabolite BH4 in dopaminergic neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.08.539795. [PMID: 37214873 PMCID: PMC10197517 DOI: 10.1101/2023.05.08.539795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Dopa-responsive dystonia (DRD) and Parkinson's disease (PD) are movement disorders caused by the dysfunction of nigrostriatal dopaminergic neurons. Identifying druggable pathways and biomarkers for guiding therapies is crucial due to the debilitating nature of these disorders. Recent genetic studies have identified variants of GTP cyclohydrolase-1 (GCH1), the rate-limiting enzyme in tetrahydrobiopterin (BH4) synthesis, as causative for these movement disorders. Here, we show that genetic and pharmacological inhibition of BH4 synthesis in mice and human midbrain-like organoids accurately recapitulates motor, behavioral and biochemical characteristics of these human diseases, with severity of the phenotype correlating with extent of BH4 deficiency. We also show that BH4 deficiency increases sensitivities to several PD-related stressors in mice and PD human cells, resulting in worse behavioral and physiological outcomes. Conversely, genetic and pharmacological augmentation of BH4 protects mice from genetically- and chemically induced PD-related stressors. Importantly, increasing BH4 levels also protects primary cells from PD-affected individuals and human midbrain-like organoids (hMLOs) from these stressors. Mechanistically, BH4 not only serves as an essential cofactor for dopamine synthesis, but also independently regulates tyrosine hydroxylase levels, protects against ferroptosis, scavenges mitochondrial ROS, maintains neuronal excitability and promotes mitochondrial ATP production, thereby enhancing mitochondrial fitness and cellular respiration in multiple preclinical PD animal models, human dopaminergic midbrain-like organoids and primary cells from PD-affected individuals. Our findings pinpoint the BH4 pathway as a key metabolic program at the intersection of multiple protective mechanisms for the health and function of midbrain dopaminergic neurons, identifying it as a potential therapeutic target for PD.
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Affiliation(s)
- Shane J F Cronin
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Weonjin Yu
- Signature Program in Neuroscience and Behavioural Disorders, Duke-National University of Singapore (NUS) Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Ashley Hale
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Simon Licht-Mayer
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Mark J Crabtree
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Joanna A Korecka
- Neurodegeneration Research Institute, Harvard Medical School/McLean Hospital, Belmont, MA, 02478, USA
| | - Evgenii O Tretiakov
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Marco Sealey-Cardona
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Mate Somlyay
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Masahiro Onji
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Meilin An
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Jesse D Fox
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Bruna Lenfers Turnes
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Carlos Gomez-Diaz
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Débora da Luz Scheffer
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC 88037-100, Brazil
| | - Domagoj Cikes
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Vanja Nagy
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases (LBI-RUD); Department of Neurology, Medical University of Vienna (MUW), 1090 Vienna, Austria
| | - Adelheid Weidinger
- Ludwig Boltzmann Institute for Traumatology. The Research Center in Cooperation with AUVA, Donaueschingen Str. 13, 1200 Vienna, Austria
| | - Alexandra Wolf
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Harald Reither
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Antoine Chabloz
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Anoop Kavirayani
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Shuan Rao
- Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Nick Andrews
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Alban Latremoliere
- Neurosurgery Department, Neurosurgery Pain Research Institute, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Michael Costigan
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Gillian Douglas
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | | | - Christian Pifl
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Roger Walz
- Center for Applied Neurocience, Universidade Federal de Santa Catarina (UFSC), Florianópolis, Brazil; Neurology Division, Internal Medicine Department, University Hospital of UFSC, Florianópolis, Brazil
| | - Robert Konrat
- Department of Structural and Computational Biology, Max Perutz Labs, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Don J Mahad
- Centre for Clinical Brain Sciences, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh, EH16 4SB, UK
| | - Andrey V Koslov
- Ludwig Boltzmann Institute for Traumatology. The Research Center in Cooperation with AUVA, Donaueschingen Str. 13, 1200 Vienna, Austria
| | - Alexandra Latini
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC 88037-100, Brazil
| | - Ole Isacson
- Neurodegeneration Research Institute, Harvard Medical School/McLean Hospital, Belmont, MA, 02478, USA
| | - Tibor Harkany
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Neuroscience, Biomedicum 7D, Karolinska Institute, Solna, Sweden
| | - Penelope J Hallett
- Neurodegeneration Research Institute, Harvard Medical School/McLean Hospital, Belmont, MA, 02478, USA
| | - Stefan Bagby
- Department of Biology and Biochemistry and the Milner Centre for Evolution, University of Bath, Bath, UK
| | - Clifford J Woolf
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Keith M Channon
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Hyunsoo Shawn Je
- Signature Program in Neuroscience and Behavioural Disorders, Duke-National University of Singapore (NUS) Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Josef M Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
- Department of Medical Genetics, Life Sciences Institute, University of British Columbia, Vancouver, Canada
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3
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Ilari A, Curti L, Petrella M, Cannella N, La Rocca A, Ranieri G, Gerace E, Iezzi D, Silvestri L, Mannaioni G, Ciccocioppo R, Masi A. Moderate ethanol drinking is sufficient to alter Ventral Tegmental Area dopamine neurons activity via functional and structural remodeling of GABAergic transmission. Neuropharmacology 2022; 203:108883. [PMID: 34785165 DOI: 10.1016/j.neuropharm.2021.108883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/29/2021] [Accepted: 11/10/2021] [Indexed: 10/19/2022]
Abstract
Earlier studies have shown a major involvement of Ventral Tegmental Area (VTA) dopamine (DA) neurons in mediating the rewarding effects of ethanol (EtOH). Much less is known on the role of this system in mediating the transition from moderate to excessive drinking and abuse. Here we sought to explore the hypothesis that early stage drinking in rodents, resembling recreational EtOH use in humans, is sufficient to dysregulate VTA DA transmission thus increasing the propensity to use over time. To this purpose, midbrain slice recordings in mice previously exposed to an escalating (3, 6 and 12%) 18-day voluntary EtOH drinking paradigm was used. By recording from DA and γ-aminobutyric acid (GABA) VTA neurons in midbrain slices, we found that moderate EtOH drinking leads to a significant suppression of the spontaneous activity of VTA DA neurons, while increasing their response to acute EtOH application. We also found that chronic EtOH leads to the enhancement of GABA input frequency onto a subset of DA neurons. Structurally, chronic EtOH induced a significant increase in the number of GABA axonal boutons contacting DA neurons, suggesting deep rewiring of the GABA network. This scenario is consistent with a downmodulation of the reward DA system induced by moderate EtOH drinking, a neurochemical state defined as "hypodopaminergic" and previously associated with advanced stages of drug use in humans. In this context, increased sensitivity of DA neurons towards acute EtOH may represent the neurophysiological correlate of increased unitary rewarding value, possibly driving progression to addiction.
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Affiliation(s)
- A Ilari
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy
| | - L Curti
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy
| | - M Petrella
- Scuola di Scienze del Farmaco e dei Prodotti della salute, Università di Camerino, Italy
| | - N Cannella
- Scuola di Scienze del Farmaco e dei Prodotti della salute, Università di Camerino, Italy
| | - A La Rocca
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy
| | - G Ranieri
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy
| | - E Gerace
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy
| | - D Iezzi
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy
| | - L Silvestri
- Dipartimento di Fisica ed Astronomia, Università di Firenze, Italy; European Laboratory for Non-linear Spectroscopy, Italy
| | - G Mannaioni
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy
| | - R Ciccocioppo
- Scuola di Scienze del Farmaco e dei Prodotti della salute, Università di Camerino, Italy.
| | - A Masi
- Dipartimento di Neuroscienze, Psicologia, Area del Farmaco e Salute del Bambino, NEUROFARBA, Università di Firenze, Italy.
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4
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Daniel NH, Aravind A, Thakur P. Are ion channels potential therapeutic targets for Parkinson's disease? Neurotoxicology 2021; 87:243-257. [PMID: 34699791 DOI: 10.1016/j.neuro.2021.10.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/15/2021] [Accepted: 10/21/2021] [Indexed: 01/31/2023]
Abstract
Parkinson's disease (PD) is primarily associated with the progressive neurodegeneration of the dopaminergic neurons in the substantia nigra region of the brain. The resulting motor symptoms are managed with the help of dopamine replacement therapies. However, these therapeutics do not prevent the neurodegeneration underlying the disease and therefore lose their effectiveness in managing disease symptoms over time. Thus, there is an urgent need to develop newer therapeutics for the benefit of patients. The release of dopamine and the firing activity of substantia nigra neurons is regulated by several ion channels that act in concert. Dysregulations of these channels cause the aberrant movement of various ions in the intracellular milieu. This eventually leads to disruption of intracellular signalling cascades, alterations in cellular homeostasis, and bioenergetic deficits. Therefore, ion channels play a central role in driving the high vulnerability of dopaminergic neurons to degenerate during PD. Targeting ion channels offers an attractive mechanistic strategy to combat the process of neurodegeneration. In this review, we highlight the evidence pointing to the role of various ion channels in driving the PD processes. In addition, we also discuss the various drugs or compounds that target the ion channels and have shown neuroprotective potential in the in-vitro and in-vivo models of PD. We also discuss the current clinical status of various drugs targeting the ion channels in the context of PD.
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Affiliation(s)
- Neha Hanna Daniel
- School of Biology, Indian Institute of Science Education and Research (IISER)-Thiruvananthapuram, Kerala, 695551, India
| | - Ananya Aravind
- School of Biology, Indian Institute of Science Education and Research (IISER)-Thiruvananthapuram, Kerala, 695551, India
| | - Poonam Thakur
- School of Biology, Indian Institute of Science Education and Research (IISER)-Thiruvananthapuram, Kerala, 695551, India.
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5
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Porro A, Abbandonato G, Veronesi V, Russo A, Binda A, Antolini L, Granata T, Castellotti B, Marini C, Moroni A, DiFrancesco JC, Rivolta I. Do the functional properties of HCN1 mutants correlate with the clinical features in epileptic patients? PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:147-155. [PMID: 34310985 DOI: 10.1016/j.pbiomolbio.2021.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 06/14/2021] [Accepted: 07/20/2021] [Indexed: 10/20/2022]
Abstract
The altered function of the Hyperpolarization-activated Cyclic-Nucleotide-gated (HCN) ion channels plays an important role in the pathogenesis of epilepsy in humans. In particular, HCN1 missense mutations have been recently identified in patients with different epileptic phenotypes, varying from mild to severe. Their electrophysiological characterization shows that mutated channels can act both with loss-of-function and gain-of-function mechanisms of action, without an evident correlation with the phenotype. In search for a correlation between clinical features and biophysical properties of the mutations, in this work we considered sixteen HCN1 mutations, found in eighteen Early Infantile Epileptic Encephalopathy (EIEE) patients. Statistical analysis did not establish any significant correlation between the clinical parameters and the current properties of the mutant channels. The lack of significance of our results could depend on the small number of mutations analyzed, epilepsy-associated with certainty. With the progressive increase of Next Generation Sequencing in patients with early-onset epilepsy, it is expected that the number of patients with HCN1 mutations will grow steadily. Functional characterization of epilepsy-associated HCN1 mutations remains a fundamental tool for a better understanding of the pathogenetic mechanisms leading to the disease in humans.
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Affiliation(s)
| | | | - Valentina Veronesi
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.
| | - Alberto Russo
- Department of Biosciences, University of Milan, Milan, Italy.
| | - Anna Binda
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.
| | - Laura Antolini
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.
| | - Tiziana Granata
- Department of Pediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
| | - Barbara Castellotti
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
| | - Carla Marini
- Department of Child Neuropsychiatry, Children's Hospital, Ancona, Italy.
| | - Anna Moroni
- Department of Biosciences, University of Milan, Milan, Italy.
| | - Jacopo C DiFrancesco
- Department of Pediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy; Department of Neurology, Epilepsy Center, ASST San Gerardo Hospital, University of Milano- Bicocca, Monza, Italy.
| | - Ilaria Rivolta
- School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, Monza, Italy.
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6
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La Barbera L, Vedele F, Nobili A, Krashia P, Spoleti E, Latagliata EC, Cutuli D, Cauzzi E, Marino R, Viscomi MT, Petrosini L, Puglisi-Allegra S, Melone M, Keller F, Mercuri NB, Conti F, D'Amelio M. Nilotinib restores memory function by preventing dopaminergic neuron degeneration in a mouse model of Alzheimer's Disease. Prog Neurobiol 2021; 202:102031. [PMID: 33684513 DOI: 10.1016/j.pneurobio.2021.102031] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 02/15/2021] [Accepted: 02/28/2021] [Indexed: 01/18/2023]
Abstract
What happens precociously to the brain destined to develop Alzheimer's Disease (AD) still remains to be elucidated and this is one reason why effective AD treatments are missing. Recent experimental and clinical studies indicate that the degeneration of the dopaminergic (DA) neurons in the Ventral Tegmental Area (VTA) could be one of the first events occurring in AD. However, the causes of the increased vulnerability of DA neurons in AD are missing. Here, we deeply investigate the physiology of DA neurons in the VTA before, at the onset, and after onset of VTA neurodegeneration. We use the Tg2576 mouse model of AD, overexpressing a mutated form of the human APP, to identify molecular targets that can be manipulated pharmacologically. We show that in Tg2576 mice, DA neurons of the VTA at the onset of degeneration undergo slight but functionally relevant changes in their electrophysiological properties and cell morphology. Importantly, these changes are associated with accumulation of autophagosomes, suggestive of a dysfunctional autophagy, and with enhanced activation of c-Abl, a tyrosine kinase previously implicated in the pathogenesis of neurodegenerative diseases. Chronic treatment of Tg2576 mice with Nilotinib, a validated c-Abl inhibitor, reduces c-Abl phosphorylation, improves autophagy, reduces Aβ levels and - more importantly - prevents degeneration as well as functional and morphological alterations in DA neurons of the VTA. Interestingly, the drug prevents the reduction of DA outflow to the hippocampus and ameliorates hippocampal-related cognitive functions. Our results strive to identify early pathological brain changes in AD, to provide a rational basis for new therapeutic interventions able to slow down the disease progression.
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Affiliation(s)
- Livia La Barbera
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy; Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy
| | - Francescangelo Vedele
- Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata, 00133, Rome, Italy
| | - Annalisa Nobili
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy; Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy
| | - Paraskevi Krashia
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy; Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy.
| | - Elena Spoleti
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy
| | | | - Debora Cutuli
- Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy; Department of Psychology, Sapienza University of Rome, 00185, Rome, Italy
| | - Emma Cauzzi
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy; School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Ramona Marino
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy
| | - Maria Teresa Viscomi
- Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy; Department of Life Science and Public Health Section of Histology and Embryology, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Laura Petrosini
- Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy
| | | | - Marcello Melone
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche (UNIVPM), 60020, Ancona, Italy; Center for Neurobiology of Aging, IRCCS Istituto Nazionale Ricovero e Cura Anziani (INRCA), 60020, Ancona, Italy
| | - Flavio Keller
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy
| | - Nicola Biagio Mercuri
- Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata, 00133, Rome, Italy
| | - Fiorenzo Conti
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche (UNIVPM), 60020, Ancona, Italy; Center for Neurobiology of Aging, IRCCS Istituto Nazionale Ricovero e Cura Anziani (INRCA), 60020, Ancona, Italy; Foundation for Molecular Medicine, Università Politecnica delle Marche, 60020, Ancona, Italy
| | - Marcello D'Amelio
- Department of Medicine and Surgery, Department of Sciences and Technologies for Humans and Environment, University Campus Bio-Medico, 00128, Rome, Italy; Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, 00143, Rome, Italy.
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7
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López‐Gambero AJ, Rodríguez de Fonseca F, Suárez J. Energy sensors in drug addiction: A potential therapeutic target. Addict Biol 2021; 26:e12936. [PMID: 32638485 DOI: 10.1111/adb.12936] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 06/10/2020] [Accepted: 06/15/2020] [Indexed: 01/05/2023]
Abstract
Addiction is defined as the repeated exposure and compulsive seek of psychotropic drugs that, despite the harmful effects, generate relapse after the abstinence period. The psychophysiological processes associated with drug addiction (acquisition/expression, withdrawal, and relapse) imply important alterations in neurotransmission and changes in presynaptic and postsynaptic plasticity and cellular structure (neuroadaptations) in neurons of the reward circuits (dopaminergic neuronal activity) and other corticolimbic regions. These neuroadaptation mechanisms imply important changes in neuronal energy balance and protein synthesis machinery. Scientific literature links drug-induced stimulation of dopaminergic and glutamatergic pathways along with presence of neurotrophic factors with alterations in synaptic plasticity and membrane excitability driven by metabolic sensors. Here, we provide current knowledge of the role of molecular targets that constitute true metabolic/energy sensors such as AMPK, mTOR, ERK, or KATP in the development of the different phases of addiction standing out the main brain regions (ventral tegmental area, nucleus accumbens, hippocampus, and amygdala) constituting the hubs in the development of addiction. Because the available treatments show very limited effectiveness, evaluating the drug efficacy of AMPK and mTOR specific modulators opens up the possibility of testing novel pharmacotherapies for an individualized approach in drug abuse.
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Affiliation(s)
- Antonio Jesús López‐Gambero
- Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga Universidad de Málaga Málaga Spain
| | - Fernando Rodríguez de Fonseca
- Instituto de Investigación Biomédica de Málaga (IBIMA), UGC Salud Mental Hospital Regional Universitario de Málaga Málaga Spain
| | - Juan Suárez
- Instituto de Investigación Biomédica de Málaga (IBIMA), UGC Salud Mental Hospital Regional Universitario de Málaga Málaga Spain
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8
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Zhao S, Wang M, Ma Z. Therapeutic potential of ATP-sensitive potassium channels in Parkinson's disease. Brain Res Bull 2021; 169:1-7. [PMID: 33434622 DOI: 10.1016/j.brainresbull.2021.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 12/19/2020] [Accepted: 01/04/2021] [Indexed: 11/19/2022]
Abstract
In the past decade, there was an increasing interest in the therapeutic potential targeting ATP-sensitive potassium (KATP) channels for an effective treatment of Parkinson's disease (PD). KATP channels are widely expressed in the central nervous system and were reported to mediate the degeneration and death of nigral dopamine neurons in the pathogenesis of PD. This review aims to address the pivotal roles of KATP channels played in the mechanisms underlying PD pathogenesis, and provide possible directions for further research from different perspectives, such as the vulnerability of dopamine neurons in the substantia nigra, neurotransmitter releasing, iron metabolism in the brain, α-synuclein secretion and mitochondrial dysfunction, which are off critical importance in the investigation of KATP channels-targeted precise therapeutic interventions for PD.
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Affiliation(s)
- Sha Zhao
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - MengZhen Wang
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - ZeGang Ma
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China; Institute of Brain Science and Disorders, Qingdao University, Qingdao, China.
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9
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Chen C, Liu L, Shu YQ, Jing P, Lu Y, Zhang XX, Zong XG, Guo LJ, Li CJ. Blockade of HCN2 Channels Provides Neuroprotection Against Ischemic Injury via Accelerating Autophagic Degradation in Hippocampal Neurons. Neurosci Bull 2020; 36:875-894. [PMID: 32519067 PMCID: PMC7410947 DOI: 10.1007/s12264-020-00513-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 02/16/2020] [Indexed: 01/25/2023] Open
Abstract
In the central nervous system, hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are essential to maintain normal neuronal function. Recent studies have shown that HCN channels may be involved in the pathological process of ischemic brain injury, but the mechanisms remain unclear. Autophagy is activated in cerebral ischemia, but its role in cell death/survival remains controversial. In this study, our results showed that the HCN channel blocker ZD7288 remarkably decreased the percentage of apoptotic neurons and corrected the excessive autophagy induced by oxygen-glucose deprivation followed by reperfusion (OGD/R) in hippocampal HT22 neurons. Furthermore, in the OGD/R group, p-mTOR, p-ULK1 (Ser757), and p62 were significantly decreased, while p-ULK1 (Ser317), atg5, and beclin1 were remarkably increased. ZD7288 did not change the expression of p-ULK1 (Ser757), ULK1 (Ser317), p62, Beclin1, and atg5, which are involved in regulating autophagosome formation. Besides, we found that OGD/R induced a significant increase in Cathepsin D expression, but not LAMP-1. Treatment with ZD7288 at 10 μmol/L in the OGD/R group did not change the expression of cathepsin D and LAMP-1. However, chloroquine (CQ), which decreases autophagosome-lysosome fusion, eliminated the correction of excessive autophagy and neuroprotection by ZD7288. Besides, shRNA knockdown of HCN2 channels significantly reduced the accumulation of LC3-II and increased neuron survival in the OGD/R and transient global cerebral ischemia (TGCI) models, and CQ also eliminated the effects of HCN2-shRNA. Furthermore, we found that the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes decreased in Con-shRNA-transfected HT22 neurons exposed to OGD/R or CQ. In HCN2-shRNA-transfected HT22 neurons, the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes increased under OGD/R; however, the percentage was significantly decreased by the addition of CQ to HCN2-shRNA-transfected HT22 neurons. The present results demonstrated that blockade of HCN2 channels provides neuroprotection against OGD/R and TGCI by accelerating autophagic degradation attributable to the promotion of autophagosome and lysosome fusion.
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Affiliation(s)
- Cheng Chen
- Department of Pharmacology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Li Liu
- Office of Academic Research, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ya-Qiao Shu
- Department of Pharmacology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ping Jing
- Department of Neurology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yun Lu
- Department of Pharmacy, Zhongnan Hospital of Wuhan University, Wuhan, 430030, China
| | - Xiao-Xue Zhang
- Department of Clinical Laboratory, Wuhan PuAi Hospital, Wuhan, 430033, China
| | - Xian-Gang Zong
- Center for Integrated Protein Science and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 80539, Munich, Germany
| | - Lian-Jun Guo
- Department of Pharmacology, School of Basic Medical Sciences, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation, Wuhan, 430030, China.
| | - Chang-Jun Li
- Department of Neurology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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10
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Rivolta I, Binda A, Masi A, DiFrancesco JC. Cardiac and neuronal HCN channelopathies. Pflugers Arch 2020; 472:931-951. [PMID: 32424620 DOI: 10.1007/s00424-020-02384-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/21/2020] [Accepted: 04/24/2020] [Indexed: 12/31/2022]
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are expressed as four different isoforms (HCN1-4) in the heart and in the central and peripheral nervous systems. In the voltage range of activation, HCN channels carry an inward current mediated by Na+ and K+, termed If in the heart and Ih in neurons. Altered function of HCN channels, mainly HCN4, is associated with sinus node dysfunction and other arrhythmias such as atrial fibrillation, ventricular tachycardia, and atrioventricular block. In recent years, several data have also shown that dysfunctional HCN channels, in particular HCN1, but also HCN2 and HCN4, can play a pathogenic role in epilepsy; these include experimental data from animal models, and data collected over genetic mutations of the channels identified and characterized in epileptic patients. In the central nervous system, alteration of the Ih current could predispose to the development of neurodegenerative diseases such as Parkinson's disease; since HCN channels are widely expressed in the peripheral nervous system, their dysfunctional behavior could also be associated with the pathogenesis of neuropathic pain. Given the fundamental role played by the HCN channels in the regulation of the discharge activity of cardiac and neuronal cells, the modulation of their function for therapeutic purposes is under study since it could be useful in various pathological conditions. Here we review the present knowledge of the HCN-related channelopathies in cardiac and neurological diseases, including clinical, genetic, therapeutic, and physiopathological aspects.
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Affiliation(s)
- Ilaria Rivolta
- School of Medicine and Surgery, Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, Monza, Italy
| | - Anna Binda
- School of Medicine and Surgery, Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, Monza, Italy
| | - Alessio Masi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Jacopo C DiFrancesco
- School of Medicine and Surgery, Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, Monza, Italy. .,Department of Neurology, ASST San Gerardo Hospital, University of Milano-Bicocca, Via Pergolesi, 33, 20900, Monza, MB, Italy.
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11
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Loss of fragile X mental retardation protein precedes Lewy pathology in Parkinson's disease. Acta Neuropathol 2020; 139:319-345. [PMID: 31768670 DOI: 10.1007/s00401-019-02099-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/10/2019] [Accepted: 11/11/2019] [Indexed: 12/11/2022]
Abstract
Parkinson's disease (PD) is the most common neurodegenerative movement disorder and is characterized by the progressive loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc) and the gradual appearance of α-synuclein (α-syn)-containing neuronal protein aggregates. Although the exact mechanism of α-syn-mediated cell death remains elusive, recent research suggests that α-syn-induced alterations in neuronal excitability contribute to cell death in PD. Because the fragile X mental retardation protein (FMRP) controls the expression and function of numerous neuronal genes related to neuronal excitability and synaptic function, we here investigated the role of FMRP in α-syn-associated pathological changes in cell culture and mouse models of PD as well as in post-mortem human brain tissue from PD patients. We found FMRP to be decreased in cultured DA neurons and in the mouse brain in response to α-syn overexpression. FMRP was, furthermore, lost in the SNc of PD patients and in patients with early stages of incidental Lewy body disease (iLBD). Unlike fragile X syndrome (FXS), FMR1 expression in response to α-syn was regulated by a mechanism involving Protein Kinase C (PKC) and cAMP response element-binding protein (CREB). Reminiscent of FXS neurons, α-syn-overexpressing cells exhibited an increase in membrane N-type calcium channels, increased phosphorylation of ERK1/2, eIF4E and S6, increased overall protein synthesis, and increased expression of Matrix Metalloproteinase 9 (MMP9). FMRP affected neuronal function in a PD animal model, because FMRP-KO mice were resistant to the effect of α-syn on striatal dopamine release. In summary, our results thus reveal a new role of FMRP in PD and support the examination of FMRP-regulated genes in PD disease progression.
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12
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Masi A, Narducci R, Mannaioni G. Harnessing ionic mechanisms to achieve disease modification in neurodegenerative disorders. Pharmacol Res 2019; 147:104343. [PMID: 31279830 DOI: 10.1016/j.phrs.2019.104343] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/19/2019] [Accepted: 07/03/2019] [Indexed: 12/12/2022]
Abstract
Progressive neuronal death is the key pathogenic event leading to clinical symptoms in neurodegenerative disorders (NDDs). Neuroprotective treatments are virtually unavailable, partly because of the marked internal heterogeneity of the mechanisms underlying pathology. Targeted neuroprotection would require deep mechanistic knowledge across the entire aetiological spectrum of each NDD and the development of tailored treatments. Although ideal, this strategy appears challenging, as it would require a degree of characterization of both the disease and the patient that is currently unavailable. The alternate strategy is to search for commonalities across molecularly distinct NDD forms and exploit these for the development of drugs with broad-spectrum efficacy. In this view, mounting evidence points to ionic mechanisms (IMs) as targets with potential therapeutic efficacy across distinct NDD subtypes. The scope of this review is to present clinical and preclinical evidence supporting the link between disruption of IMs and neuronal death in specific NDDs and to critically revise past and ongoing attempts of harnessing IMs for the development of neuroprotective treatments.
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Affiliation(s)
- A Masi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy; School of Pharmacy, University of Camerino, Camerino, Italy.
| | - R Narducci
- Italian Institute of Technology (IIT), Department of Neuroscience and Brain Technologies, Genova, Italy
| | - G Mannaioni
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy; Toxicology Unit, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
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13
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Chang X, Wang J, Jiang H, Shi L, Xie J. Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: An Emerging Role in Neurodegenerative Diseases. Front Mol Neurosci 2019; 12:141. [PMID: 31231190 PMCID: PMC6560157 DOI: 10.3389/fnmol.2019.00141] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 05/13/2019] [Indexed: 12/13/2022] Open
Abstract
Neurodegenerative diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and spinal muscular atrophy (SMA) are chronic, progressive, and age-associated neurological disorders characterized by neuronal deterioration in specific brain regions. Although the specific pathological mechanisms underlying these disorders have remained elusive, ion channel dysfunction has become increasingly accepted as a potential mechanism for neurodegenerative diseases. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are encoded by the HCN1-4 gene family and conduct the hyperpolarization-activated current (I h). These channels play important roles in modulating cellular excitability, rhythmic activity, dendritic integration, and synaptic transmission. In the present review, we first provide a comprehensive picture of the role of HCN channels in PD by summarizing their role in the regulation of neuronal activity in PD-related brain regions. Dysfunction of I h may participate in 1-methyl-4-phenylpyridinium (MPP+)-induced toxicity and represent a pathogenic mechanism in PD. Given current reports of the critical role of HCN channels in neuroinflammation and depression, we also discussed the putative contribution of HCN channels in inflammatory processes and non-motor symptoms in PD. In the second section, we summarize how HCN channels regulate the formation of β-amyloid peptide in AD and the role of these channels in learning and memory. Finally, we briefly discuss the effects of HCN channels in ALS and SMA based on existing discoveries.
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Affiliation(s)
- Xiaoli Chang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Jun Wang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Hong Jiang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Limin Shi
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Junxia Xie
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Qingdao University, Qingdao, China
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14
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Luo P, He G, Liu D. HCN channels: New targets for the design of an antidepressant with rapid effects. J Affect Disord 2019; 245:764-770. [PMID: 30448761 DOI: 10.1016/j.jad.2018.11.081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 10/22/2018] [Accepted: 11/11/2018] [Indexed: 12/18/2022]
Abstract
BACKGROUND Major depressive disorder (MDD) is a prevalent neuropsychiatric disease that carries a staggering global burden. Although numerous antidepressants are available on the market, unfortunately, many patients die by committing suicide as a result of the therapeutic lag between treatment initiation and the improvement of depressive symptoms. This therapeutic lag highlights the need for new antidepressants that provide rapid relief of depressive symptoms. METHOD In this review, we discuss the seminal researches on hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in animal models of depression and highlight the substantial evidence supporting the development of rapid-acting antidepressants targeting HCN channels. RESULTS HCN channels are associated with the risk of depression and targeting HCN channels or its auxiliary subunit tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b) function may exert a rapid antidepressant-like effect. CONCLUSIONS Compounds acting on HCN subunits or the TRIP8b-HCN interaction site may be excellent candidates for development into effective drugs with rapid antidepressant action.
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Affiliation(s)
- Pan Luo
- Department of Pharmacy, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - GuoFang He
- Department of Pharmacy, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
| | - Dong Liu
- Department of Pharmacy, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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15
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Yang SS, Li YC, Coley AA, Chamberlin LA, Yu P, Gao WJ. Cell-Type Specific Development of the Hyperpolarization-Activated Current, Ih, in Prefrontal Cortical Neurons. Front Synaptic Neurosci 2018; 10:7. [PMID: 29867437 PMCID: PMC5958189 DOI: 10.3389/fnsyn.2018.00007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 04/24/2018] [Indexed: 11/13/2022] Open
Abstract
H-current, also known as hyperpolarization-activated current (Ih), is an inward current generated by the hyperpolarization-activated cyclic nucleotide-gated (HCN) cation channels. Ih plays an essential role in regulating neuronal properties, synaptic integration and plasticity, and synchronous activity in the brain. As these biological factors change across development, the brain undergoes varying levels of vulnerability to disorders like schizophrenia that disrupt prefrontal cortex (PFC)-dependent function. However, developmental changes in Ih in PFC neurons remains untested. Here, we examine Ih in pyramidal neurons vs. gamma-aminobutyric acid (GABA)ergic parvalbumin-expressing (PV+) interneurons in developing mouse PFC. Our findings show that the amplitudes of Ih in these cell types are identical during the juvenile period but differ at later time points. In pyramidal neurons, Ih amplitude significantly increases from juvenile to adolescence and follows a similar trend into adulthood. In contrast, the amplitude of Ih in PV+ interneurons decreases from juvenile to adolescence, and does not change from adolescence to adulthood. Moreover, the kinetics of HCN channels in pyramidal neurons is significantly slower than in PV+ interneurons, with a gradual decrease in pyramidal neurons and a gradual increase in PV+ cells across development. Our study reveals distinct developmental trajectories of Ih in pyramidal neurons and PV+ interneurons. The cell-type specific alteration of Ih during the critical period from juvenile to adolescence reflects the contribution of Ih to the maturation of the PFC and PFC-dependent function. These findings are essential for a better understanding of normal PFC function, and for elucidating Ih's crucial role in the pathophysiology of neurodevelopmental disorders.
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Affiliation(s)
- Sha-Sha Yang
- Beijing Key Laboratory of Learning and Cognition, College of Psychology, Capital Normal University, Beijing, China.,Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, United States
| | - Yan-Chun Li
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, United States
| | - Austin A Coley
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, United States
| | - Linda A Chamberlin
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, United States
| | - Ping Yu
- Beijing Key Laboratory of Learning and Cognition, College of Psychology, Capital Normal University, Beijing, China
| | - Wen-Jun Gao
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, United States
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16
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Resta F, Micheli L, Laurino A, Spinelli V, Mello T, Sartiani L, Di Cesare Mannelli L, Cerbai E, Ghelardini C, Romanelli MN, Mannaioni G, Masi A. Selective HCN1 block as a strategy to control oxaliplatin-induced neuropathy. Neuropharmacology 2018; 131:403-413. [PMID: 29339292 DOI: 10.1016/j.neuropharm.2018.01.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 12/27/2017] [Accepted: 01/09/2018] [Indexed: 01/12/2023]
Abstract
Chemotherapy-Induced Peripheral Neuropathy (CIPN) is the most frequent adverse effect of pharmacological cancer treatments. The occurrence of neuropathy prevents the administration of fully-effective drug regimen, affects negatively the quality of life of patients, and may lead to therapy discontinuation. CIPN is currently treated with anticonvulsants, antidepressants, opioids and non-opioid analgesics, all of which are flawed by insufficient anti-hyperalgesic efficacy or addictive potential. Understandably, developing new drugs targeting CIPN-specific pathogenic mechanisms would dramatically improve efficacy and tolerability of anti-neuropathic therapies. Neuropathies are associated to aberrant excitability of DRG neurons due to the alteration in the expression or function of a variety of ion channels. In this regard, Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels are overexpressed in inflammatory and neuropathic pain states, and HCN blockers have been shown to reduce neuronal excitability and to ameliorate painful states in animal models. However, HCN channels are critical in cardiac action potential, and HCN blockers used so far in pre-clinical models do not discriminate between cardiac and non-cardiac HCN isoforms. In this work, we show an HCN current gain of function in DRG neurons from oxaliplatin-treated rats. Biochemically, we observed a downregulation of HCN2 expression and an upregulation of the HCN regulatory beta-subunit MirP1. Finally, we report the efficacy of the selective HCN1 inhibitor MEL57A in reducing hyperalgesia and allodynia in oxaliplatin-treated rats without cardiac effects. In conclusion, this study strengthens the evidence for a disease-specific role of HCN1 in CIPN, and proposes HCN1-selective inhibitors as new-generation pain medications with the desired efficacy and safety profile.
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Affiliation(s)
- F Resta
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy.
| | - L Micheli
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - A Laurino
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - V Spinelli
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - T Mello
- Clinical Gastroenterology Laboratory, Department of Experimental and Clinical Biomedical Sciences, "Mario Serio" University of Florence, Florence, Italy
| | - L Sartiani
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - L Di Cesare Mannelli
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - E Cerbai
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - C Ghelardini
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - M N Romanelli
- Department of Neuroscience, Psychology, Drug Research and Child Health, Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, via Ugo Schiff 6, Sesto Fiorentino, Italy
| | - G Mannaioni
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
| | - A Masi
- Department of Neuroscience, Psychology, Drug Research and Child Health - NEUROFARBA - Pharmacology and Toxicology Section, University of Florence, Florence, Italy
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17
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Sartiani L, Mannaioni G, Masi A, Novella Romanelli M, Cerbai E. The Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: from Biophysics to Pharmacology of a Unique Family of Ion Channels. Pharmacol Rev 2017; 69:354-395. [PMID: 28878030 DOI: 10.1124/pr.117.014035] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/07/2017] [Indexed: 12/22/2022] Open
Abstract
Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels are important members of the voltage-gated pore loop channels family. They show unique features: they open at hyperpolarizing potential, carry a mixed Na/K current, and are regulated by cyclic nucleotides. Four different isoforms have been cloned (HCN1-4) that can assemble to form homo- or heterotetramers, characterized by different biophysical properties. These proteins are widely distributed throughout the body and involved in different physiologic processes, the most important being the generation of spontaneous electrical activity in the heart and the regulation of synaptic transmission in the brain. Their role in heart rate, neuronal pacemaking, dendritic integration, learning and memory, and visual and pain perceptions has been extensively studied; these channels have been found also in some peripheral tissues, where their functions still need to be fully elucidated. Genetic defects and altered expression of HCN channels are linked to several pathologies, which makes these proteins attractive targets for translational research; at the moment only one drug (ivabradine), which specifically blocks the hyperpolarization-activated current, is clinically available. This review discusses current knowledge about HCN channels, starting from their biophysical properties, origin, and developmental features, to (patho)physiologic role in different tissues and pharmacological modulation, ending with their present and future relevance as drug targets.
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Affiliation(s)
- Laura Sartiani
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Guido Mannaioni
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Alessio Masi
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Maria Novella Romanelli
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Elisabetta Cerbai
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
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18
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Carbone C, Costa A, Provensi G, Mannaioni G, Masi A. The Hyperpolarization-Activated Current Determines Synaptic Excitability, Calcium Activity and Specific Viability of Substantia Nigra Dopaminergic Neurons. Front Cell Neurosci 2017; 11:187. [PMID: 28701928 PMCID: PMC5487410 DOI: 10.3389/fncel.2017.00187] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/16/2017] [Indexed: 12/28/2022] Open
Abstract
Differential vulnerability between Substantia Nigra pars compacta (SNpc) and Ventral Tegmental Area (VTA) dopaminergic (DAergic) neurons is a hallmark of Parkinson’s disease (PD). Understanding the molecular bases of this key histopathological aspect would foster the development of much-needed disease-modifying therapies. Non-heterogeneous DAergic degeneration is present in both toxin-based and genetic animal models, suggesting that cellular specificity, rather than causing factors, constitutes the background for differential vulnerability. In this regard, we previously demonstrated that MPP+, a neurotoxin able to cause selective nigrostriatal degeneration in animal rodents and primates, inhibits the Hyperpolarization-activated current (Ih) in SNpc DAergic neurons and that pharmacological Ih antagonism causes potentiation of evoked Excitatory post-synaptic potentials (EPSPs). Of note, the magnitude of such potentiation is greater in the SNpc subfield, consistent with higher Ih density. In the present work, we show that Ih block-induced synaptic potentiation leads to the amplification of somatic calcium responses (SCRs) in vitro. This effect is specific for the SNpc subfield and largely mediated by L-Type calcium channels, as indicated by sensitivity to the CaV 1 blocker isradipine. Furthermore, Ih is downregulated by low intracellular ATP and determines the efficacy of GABAergic inhibition in SNpc DAergic neurons. Finally, we show that stereotaxic administration of Ih blockers causes SNpc-specific neurodegeneration and hemiparkinsonian motor phenotype in rats. During PD progression, Ih downregulation may result from mitochondrial dysfunction and, in concert with PD-related disinhibition of excitatory inputs, determine a SNpc-specific disease pathway.
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Affiliation(s)
- Carmen Carbone
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of FlorenceFlorence, Italy
| | - Alessia Costa
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of FlorenceFlorence, Italy
| | - Gustavo Provensi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of FlorenceFlorence, Italy
| | - Guido Mannaioni
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of FlorenceFlorence, Italy.,Toxicology Unit, Azienda Ospedaliero-Universitaria CareggiFlorence, Italy
| | - Alessio Masi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of FlorenceFlorence, Italy.,Toxicology Unit, Azienda Ospedaliero-Universitaria CareggiFlorence, Italy
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Arencibia-Albite F, Vázquez-Torres R, Jiménez-Rivera CA. Cocaine sensitization increases subthreshold activity in dopamine neurons from the ventral tegmental area. J Neurophysiol 2016; 117:612-623. [PMID: 27832596 DOI: 10.1152/jn.00465.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 11/07/2016] [Indexed: 11/22/2022] Open
Abstract
The progressive escalation of psychomotor responses that results from repeated cocaine administration is termed sensitization. This phenomenon alters the intrinsic properties of dopamine (DA) neurons from the ventral tegmental area (VTA), leading to enhanced dopaminergic transmission in the mesocorticolimbic network. The mechanisms underlying this augmented excitation are nonetheless poorly understood. DA neurons display the hyperpolarization-activated, nonselective cation current, dubbed Ih We recently demonstrated that Ih and membrane capacitance are substantially reduced in VTA DA cells from cocaine-sensitized rats. The present study shows that 7 days of cocaine withdrawal did not normalize Ih and capacitance. In cells from cocaine-sensitized animals, the amplitude of excitatory synaptic potentials, at -70 mV, was ∼39% larger in contrast to controls. Raise and decay phases of the synaptic signal were faster under cocaine, a result associated with a reduced membrane time constant. Synaptic summation was paradoxically elevated by cocaine exposure, as it consisted of a significantly reduced summation indexed but a considerably increased depolarization. These effects are at least a consequence of the reduced capacitance. Ih attenuation is unlikely to explain such observations, since at -70 mV, no statistical differences exist in Ih or input resistance. The neuronal shrinkage associated with a diminished capacitance may help to understand two fundamental elements of drug addiction: incentive sensitization and negative emotional states. A reduced cell size may lead to substantial enhancement of cue-triggered bursting, which underlies drug craving and reward anticipation, whereas it could also result in DA depletion, as smaller neurons might express low levels of tyrosine hydroxylase. NEW & NOTEWORTHY This work uses a new approach that directly extracts important biophysical parameters from alpha function-evoked synaptic potentials. Two of these parameters are the cell membrane capacitance (Cm) and rate at any time point of the synaptic waveform. The use of such methodology shows that cocaine sensitization reduces Cm and increases the speed of synaptic signaling. Paradoxically, although synaptic potentials show a faster decay under cocaine their temporal summation is substantially elevated.
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Affiliation(s)
- Francisco Arencibia-Albite
- Department of Physiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico; and.,Departamento de Ciencias Naturales, Universidad del Sagrado Corazón, San Juan, Puerto Rico
| | - Rafael Vázquez-Torres
- Department of Physiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico; and
| | - Carlos A Jiménez-Rivera
- Department of Physiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico; and
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Engel D. Subcellular Patch-clamp Recordings from the Somatodendritic Domain of Nigral Dopamine Neurons. J Vis Exp 2016. [PMID: 27842379 PMCID: PMC5226116 DOI: 10.3791/54601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Dendrites of dopaminergic neurons receive and convey synaptic input, support action potential back-propagation and neurotransmitter release. Understanding these fundamental functions will shed light on the information transfer in these neurons. Dendritic patch-clamp recordings provide the possibility to directly examine the electrical properties of dendrites and underlying voltage-gated ion channels. However, these fine structures are not easily accessible to patch pipettes because of their small diameter. This report describes a step-by-step procedure to collect stable and reliable recordings from the dendrites of dopaminergic neurons in acute slices. Electrophysiological measurements are combined with post hoc recovery of cell morphology. Successful experiments rely on improved preparation of slices, solutions and pipettes, adequate adjustment of the optics and stability of the pipette in contact with the recorded structure. Standard principles of somatic patch-clamp recording are applied to dendrites but with a gentler approach of the pipette. These versatile techniques can be implemented to address various questions concerning the excitable properties of dendrites.
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Ceballos CC, Li S, Roque AC, Tzounopoulos T, Leão RM. Ih Equalizes Membrane Input Resistance in a Heterogeneous Population of Fusiform Neurons in the Dorsal Cochlear Nucleus. Front Cell Neurosci 2016; 10:249. [PMID: 27833532 PMCID: PMC5081345 DOI: 10.3389/fncel.2016.00249] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 10/10/2016] [Indexed: 11/22/2022] Open
Abstract
In a neuronal population, several combinations of its ionic conductances are used to attain a specific firing phenotype. Some neurons present heterogeneity in their firing, generally produced by expression of a specific conductance, but how additional conductances vary along in order to homeostatically regulate membrane excitability is less known. Dorsal cochlear nucleus principal neurons, fusiform neurons, display heterogeneous spontaneous action potential activity and thus represent an appropriate model to study the role of different conductances in establishing firing heterogeneity. Particularly, fusiform neurons are divided into quiet, with no spontaneous firing, or active neurons, presenting spontaneous, regular firing. These modes are determined by the expression levels of an intrinsic membrane conductance, an inwardly rectifying potassium current (IKir). In this work, we tested whether other subthreshold conductances vary homeostatically to maintain membrane excitability constant across the two subtypes. We found that Ih expression covaries specifically with IKir in order to maintain membrane resistance constant. The impact of Ih on membrane resistance is dependent on the level of IKir expression, being much smaller in quiet neurons with bigger IKir, but Ih variations are not relevant for creating the quiet and active phenotypes. Finally, we demonstrate that the individual proportion of each conductance, and not their absolute conductance, is relevant for determining the neuronal firing mode. We conclude that in fusiform neurons the variations of their different subthreshold conductances are limited to specific conductances in order to create firing heterogeneity and maintain membrane homeostasis.
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Affiliation(s)
- Cesar C Ceballos
- Department of Physiology, Ribeirão Preto Medical School, School of Medicine, University of São PauloRibeirão Preto, Brazil; Department of Physics, School of Philosophy, Sciences and Letters, University of São PauloRibeirão Preto, Brazil
| | - Shuang Li
- Department of Otolaryngology, School of Medicine, University of Pittsburgh, Pittsburgh PA, USA
| | - Antonio C Roque
- Department of Physics, School of Philosophy, Sciences and Letters, University of São Paulo Ribeirão Preto, Brazil
| | - Thanos Tzounopoulos
- Department of Otolaryngology, School of Medicine, University of Pittsburgh, PittsburghPA, USA; Department of Neurobiology, School of Medicine, University of Pittsburgh, PittsburghPA, USA
| | - Ricardo M Leão
- Department of Physiology, Ribeirão Preto Medical School, School of Medicine, University of São PauloRibeirão Preto, Brazil; Department of Otolaryngology, School of Medicine, University of Pittsburgh, PittsburghPA, USA
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Krashia P, Martini A, Nobili A, Aversa D, D'Amelio M, Berretta N, Guatteo E, Mercuri NB. On the properties of identified dopaminergic neurons in the mouse substantia nigra and ventral tegmental area. Eur J Neurosci 2016; 45:92-105. [PMID: 27519559 DOI: 10.1111/ejn.13364] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 07/29/2016] [Accepted: 08/08/2016] [Indexed: 02/06/2023]
Abstract
We studied the properties of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and ventral tegmental area (VTA) in mice expressing the enhanced green fluorescent protein (eGFP) under the control of the tyrosine hydroxylase promoter (TH-GFP). By using a practical map of cell positioning in distinct SNpc and VTA subregions in horizontal midbrain slices we saw that the spontaneous firing, membrane properties, cell body size and magnitude of the hyperpolarization-activated current (Ih ) in TH-GFP-positive neurons (TH-GFP+ ) vary significantly among subregions, following a mediolateral gradient. Block of Ih with Zd7288 inhibited firing in the most lateral subregions, but had little effect in the intermediate/medial VTA. In addition, TH-GFP+ cells were excited by Met5 -Enkephalin. Extracellular recordings from a large neuron number showed that all TH-GFP+ cells were inhibited by dopamine, suggesting that this is a reliable approach for identifying dopaminergic neurons in vitro. Simultaneous recordings from dopamine-sensitive and dopamine-insensitive neurons showed that dopamine-insensitive cells (putative non-dopaminergic neurons) are unaffected by Zd7288 but inhibited by Met5 -Enkephalin. Under patch-clamp, dopamine generated a quantitatively similar outward current in most TH-GFP+ neurons, although medial VTA cells showed reduced dopamine sensitivity. Pargyline prolonged the dopamine current, whereas cocaine enhanced dopamine-mediated responses in both the SNpc and the VTA. Our work provides new insights into the variability in mouse midbrain dopaminergic neurons along the medial-lateral axis and points to the necessity of a combination of different electrophysiological and pharmacological approaches for reliably identifying these cells to distinguish them from non-dopaminergic neurons in the midbrain.
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Affiliation(s)
- Paraskevi Krashia
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy.,Department of Systems Medicine, Faculty of Medicine, University of Rome 'Tor Vergata', Via Montpellier 1, 00133, Rome, Italy
| | - Alessandro Martini
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy.,Department of Systems Medicine, Faculty of Medicine, University of Rome 'Tor Vergata', Via Montpellier 1, 00133, Rome, Italy
| | - Annalisa Nobili
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy.,Department of Medicine, University Campus-Biomedico, Rome, Italy
| | - Daniela Aversa
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy.,Department of Systems Medicine, Faculty of Medicine, University of Rome 'Tor Vergata', Via Montpellier 1, 00133, Rome, Italy
| | - Marcello D'Amelio
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy.,Department of Medicine, University Campus-Biomedico, Rome, Italy
| | - Nicola Berretta
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy
| | - Ezia Guatteo
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy.,Department of Motor Science and Wellness, University of Naples Parthenope, Naples, Italy
| | - Nicola Biagio Mercuri
- Department of Experimental Neurology, IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143, Rome, Italy.,Department of Systems Medicine, Faculty of Medicine, University of Rome 'Tor Vergata', Via Montpellier 1, 00133, Rome, Italy
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