1
|
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.
Collapse
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.
| |
Collapse
|
2
|
Zhan Y, Raza MU, Yuan L, Zhu MY. Critical Role of Oxidatively Damaged DNA in Selective Noradrenergic Vulnerability. Neuroscience 2019; 422:184-201. [PMID: 31698021 DOI: 10.1016/j.neuroscience.2019.09.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 09/25/2019] [Accepted: 09/27/2019] [Indexed: 12/21/2022]
Abstract
An important pathology in Parkinson's disease (PD) is the earlier and more severe degeneration of noradrenergic neurons in the locus coeruleus (LC) than dopaminergic neurons in the substantia nigra. However, the basis of such selective vulnerability to insults remains obscure. Using noradrenergic and dopaminergic cell lines, as well as primary neuronal cultures from rat LC and ventral mesencephalon (VM), the present study compared oxidative DNA damage response markers after exposure of these cells to hydrogen peroxide (H2O2). The results showed that H2O2 treatment resulted in more severe cell death in noradrenergic cell lines SK-N-BE(2)-M17 and PC12 than dopaminergic MN9D cells. Furthermore, there were higher levels of oxidative DNA damage response markers in noradrenergic cells and primary neuronal cultures from the LC than dopaminergic cells and primary cultures from the VM. It included increased tail moments and tail lengths in Comet assay, and increased protein levels of phosphor-p53 and γ-H2AX after treatments with H2O2. Consistent with these measurements, exposure of SK-N-BE(2)-M17 cells to H2O2 resulted in higher levels of reactive oxygen species (ROS). Further experiments showed that exposure of SK-N-BE(2)-M17 cells to H2O2 caused an increased level of noradrenergic transporter, reduced protein levels of copper transporter (Ctr1) and 8-oxoGua DNA glycosylase, as well as amplified levels of Cav1.2 and Cav1.3 expression. Taken together, these experiments indicated that noradrenergic neuronal cells seem to be more vulnerable to oxidative damage than dopaminergic neurons, which may be related to the intrinsic characteristics of noradrenergic neuronal cells.
Collapse
Affiliation(s)
- Yanqiang Zhan
- Department of Neurology, Remin Hospital of the Wuhan University, Wuhan, China
| | - Muhammad U Raza
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA
| | - Lian Yuan
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA
| | - Meng-Yang Zhu
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA.
| |
Collapse
|
3
|
Oliveira RB, Petiz LL, Lim R, Lipski J, Gravina FS, Brichta AM, Callister RJ, Leão RN, Helden DF. Crosstalk between mitochondria, calcium channels and actin cytoskeleton modulates noradrenergic activity of locus coeruleus neurons. J Neurochem 2019; 149:471-487. [DOI: 10.1111/jnc.14692] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/22/2019] [Accepted: 02/28/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Ramatis B. Oliveira
- School of Biomedical Sciences and Pharmacy University of Newcastle and Hunter Medical Research Institute Callaghan NSW Australia
- Health and Medical Research Group School of Medicine University of the Taquari Valley ‐ Univates Lajeado RS Brazil
- Bairro Universitário Lajeado RS Brazil
| | - Lyvia L. Petiz
- School of Biomedical Sciences and Pharmacy University of Newcastle and Hunter Medical Research Institute Callaghan NSW Australia
- Brain Institute Federal University of Rio Grande do Norte Natal Brazil
| | - Rebecca Lim
- School of Biomedical Sciences and Pharmacy University of Newcastle and Hunter Medical Research Institute Callaghan NSW Australia
| | - Janusz Lipski
- Faculty of Medical and Health Sciences University of Auckland Auckland New Zealand
| | - Fernanda S. Gravina
- School of Biomedical Sciences and Pharmacy University of Newcastle and Hunter Medical Research Institute Callaghan NSW Australia
| | - Alan M. Brichta
- School of Biomedical Sciences and Pharmacy University of Newcastle and Hunter Medical Research Institute Callaghan NSW Australia
| | - Robert J. Callister
- School of Biomedical Sciences and Pharmacy University of Newcastle and Hunter Medical Research Institute Callaghan NSW Australia
| | - Richardson N. Leão
- Brain Institute Federal University of Rio Grande do Norte Natal Brazil
- The Beijer Laboratory for Gene and Neurosciences Department of Neuroscience Uppsala University Uppsala Sweden
| | - Dirk F. Helden
- School of Biomedical Sciences and Pharmacy University of Newcastle and Hunter Medical Research Institute Callaghan NSW Australia
| |
Collapse
|
4
|
Louis ED, Lenka A. The Olivary Hypothesis of Essential Tremor: Time to Lay this Model to Rest? Tremor Other Hyperkinet Mov (N Y) 2017; 7:473. [PMID: 28966877 PMCID: PMC5618117 DOI: 10.7916/d8ff40rx] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 06/09/2017] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Although essential tremor (ET) is the most common tremor disorder, its pathogenesis is not fully understood. The traditional model of ET, proposed in the early 1970s, posited that the inferior olivary nucleus (ION) was the prime generator of tremor in ET and that ET is a disorder of electrophysiological derangement, much like epilepsy. This article comprehensively reviews the origin and basis of this model, its merits and problems, and discusses whether it is time to lay this model to rest. METHODS A PubMed search was performed in March 2017 to identify articles for this review. RESULTS The olivary model gains support from the recognition of neurons with pacemaker property in the ION and the harmaline-induced tremor models (as the ION is the prime target of harmaline). However, the olivary model is problematic, as neurons with pacemaker property are not specific to the ION and the harmaline model does not completely represent the human disease ET. In addition, a large number of neuroimaging studies in ET have not detected structural or functional changes in the ION; rather, abnormalities have been reported in structures related to the cerebello-thalamo-cortical network. Moreover, a post-mortem study of microscopic changes in the ION did not detect any differences between ET cases and controls. DISCUSSION The olivary model largely remains a physiological construct. Numerous observations have cast considerable doubt as to the validity of this model in ET. Given the limitations of the model, we conclude that it is time now to lay this model to rest.
Collapse
Affiliation(s)
- Elan D. Louis
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA
- Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Abhishek Lenka
- Department of Clinical Neurosciences, National Institute of Mental Health and Neurosciences, Bangalore, India
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bangalore, India
| |
Collapse
|
5
|
Brisson CD, Hsieh YT, Kim D, Jin AY, Andrew RD. Brainstem neurons survive the identical ischemic stress that kills higher neurons: insight to the persistent vegetative state. PLoS One 2014; 9:e96585. [PMID: 24802253 PMCID: PMC4011844 DOI: 10.1371/journal.pone.0096585] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/08/2014] [Indexed: 11/19/2022] Open
Abstract
Global ischemia caused by heart attack, pulmonary failure, near-drowning or traumatic brain injury often damages the higher brain but not the brainstem, leading to a ‘persistent vegetative state’ where the patient is awake but not aware. Approximately 30,000 U.S. patients are held captive in this condition but not a single research study has addressed how the lower brain is preferentially protected in these people. In the higher brain, ischemia elicits a profound anoxic depolarization (AD) causing neuronal dysfunction and vasoconstriction within minutes. Might brainstem nuclei generate less damaging AD and so be more resilient? Here we compared resistance to acute injury induced from simulated ischemia by ‘higher’ hippocampal and striatal neurons versus brainstem neurons in live slices from rat and mouse. Light transmittance (LT) imaging in response to 10 minutes of oxygen/glucose deprivation (OGD) revealed immediate and acutely damaging AD propagating through gray matter of neocortex, hippocampus, striatum, thalamus and cerebellar cortex. In adjacent brainstem nuclei, OGD-evoked AD caused little tissue injury. Whole-cell patch recordings from hippocampal and striatal neurons under OGD revealed sudden membrane potential loss that did not recover. In contrast brainstem neurons from locus ceruleus and mesencephalic nucleus as well as from sensory and motor nuclei only slowly depolarized and then repolarized post-OGD. Two-photon microscopy confirmed non-recoverable swelling and dendritic beading of hippocampal neurons during OGD, while mesencephalic neurons in midbrain appeared uninjured. All of the above responses were mimicked by bath exposure to 100 µM ouabain which inhibits the Na+/K+ pump or to 1–10 nM palytoxin which converts the pump into an open cationic channel. Therefore during ischemia the Na+/K+ pump of higher neurons fails quickly and extensively compared to naturally resilient hypothalamic and brainstem neurons. The selective survival of lower brain regions that maintain vital functions will support the persistent vegetative state.
Collapse
Affiliation(s)
- C. Devin Brisson
- Department of Biomedical & Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Yi-Ting Hsieh
- Department of Biomedical & Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Danielle Kim
- Department of Biomedical & Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Albert Y. Jin
- Department of Biomedical & Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - R. David Andrew
- Department of Biomedical & Molecular Sciences, Queen's University, Kingston, Ontario, Canada
- * E-mail:
| |
Collapse
|
6
|
Tuckwell HC, Penington NJ. Computational modeling of spike generation in serotonergic neurons of the dorsal raphe nucleus. Prog Neurobiol 2014; 118:59-101. [PMID: 24784445 DOI: 10.1016/j.pneurobio.2014.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 04/14/2014] [Accepted: 04/21/2014] [Indexed: 01/14/2023]
Abstract
Serotonergic neurons of the dorsal raphe nucleus, with their extensive innervation of limbic and higher brain regions and interactions with the endocrine system have important modulatory or regulatory effects on many cognitive, emotional and physiological processes. They have been strongly implicated in responses to stress and in the occurrence of major depressive disorder and other psychiatric disorders. In order to quantify some of these effects, detailed mathematical models of the activity of such cells are required which describe their complex neurochemistry and neurophysiology. We consider here a single-compartment model of these neurons which is capable of describing many of the known features of spike generation, particularly the slow rhythmic pacemaking activity often observed in these cells in a variety of species. Included in the model are 11 kinds of ion channels: a fast sodium current INa, a delayed rectifier potassium current IKDR, a transient potassium current IA, a slow non-inactivating potassium current IM, a low-threshold calcium current IT, two high threshold calcium currents IL and IN, small and large conductance potassium currents ISK and IBK, a hyperpolarization-activated cation current IH and a leak current ILeak. In Sections 3-8, each current type is considered in detail and parameters estimated from voltage clamp data where possible. Three kinds of model are considered for the BK current and two for the leak current. Intracellular calcium ion concentration Cai is an additional component and calcium dynamics along with buffering and pumping is discussed in Section 9. The remainder of the article contains descriptions of computed solutions which reveal both spontaneous and driven spiking with several parameter sets. Attention is focused on the properties usually associated with these neurons, particularly long duration of action potential, steep upslope on the leading edge of spikes, pacemaker-like spiking, long-lasting afterhyperpolarization and the ramp-like return to threshold after a spike. In some cases the membrane potential trajectories display doublets or have humps or notches as have been reported in some experimental studies. The computed time courses of IA and IT during the interspike interval support the generally held view of a competition between them in influencing the frequency of spiking. Spontaneous activity was facilitated by the presence of IH which has been found in these neurons by some investigators. For reasonable sets of parameters spike frequencies between about 0.6Hz and 1.2Hz are obtained, but frequencies as high as 6Hz could be obtained with special parameter choices. Topics investigated and compared with experiment include shoulders, notches, anodal break phenomena, the effects of noradrenergic input, frequency versus current curves, depolarization block, effects of cell size and the effects of IM. The inhibitory effects of activating 5-HT1A autoreceptors are also investigated. There is a considerable discussion of in vitro versus in vivo firing behavior, with focus on the roles of noradrenergic input, corticotropin-releasing factor and orexinergic inputs. Location of cells within the nucleus is probably a major factor, along with the state of the animal.
Collapse
Affiliation(s)
- Henry C Tuckwell
- Max Planck Institute for Mathematics in the Sciences, Inselstr. 22, 04103 Leipzig, Germany; School of Electrical and Electronic Engineering, University of Adelaide, Adelaide, South Australia 5005, Australia.
| | - Nicholas J Penington
- Department of Physiology and Pharmacology, State University of New York, Downstate Medical Center, Box 29, 450 Clarkson Avenue, Brooklyn, NY 11203-2098, USA; Program in Neural and Behavioral Science and Robert F. Furchgott Center for Neural and Behavioral Science, State University of New York, Downstate Medical Center, Box 29, 450 Clarkson Avenue, Brooklyn, NY 11203-2098, USA
| |
Collapse
|
7
|
Heterogeneous responses to antioxidants in noradrenergic neurons of the Locus coeruleus indicate differing susceptibility to free radical content. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2012; 2012:820285. [PMID: 22577493 PMCID: PMC3345253 DOI: 10.1155/2012/820285] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 01/24/2012] [Accepted: 02/08/2012] [Indexed: 11/17/2022]
Abstract
The present study investigated the effects of the antioxidants trolox and dithiothreitol (DTT) on mouse Locus coeruleus (LC) neurons. Electrophysiological measurement of action potential discharge and whole cell current responses in the presence of each antioxidant suggested that there are three neuronal subpopulations within the LC. In current clamp experiments, most neurons (55%; 6/11) did not respond to the antioxidants. The remaining neurons exhibited either hyperpolarization and decreased firing rate (27%; 3/11) or depolarization and increased firing rate (18%; 2/11). Calcium and JC-1 imaging demonstrated that these effects did not change intracellular Ca2+ concentration but may influence mitochondrial function as both antioxidant treatments modulated mitochondrial membrane potential. These suggest that the antioxidant-sensitive subpopulations of LC neurons may be more susceptible to oxidative stress (e.g., due to ATP depletion and/or overactivation of Ca2+-dependent pathways). Indeed it may be that this subpopulation of LC neurons is preferentially destroyed in neurological pathologies such as Parkinson's disease. If this is the case, there may be a protective role for antioxidant therapies.
Collapse
|