51
|
Abstract
Waking up requires excitation of the brain's wake centers. A new study shows that synaptic inhibition of sleep centers also induces wakefulness. This inhibition, driven by lateral hypothalamic GABAergic neurons, may coordinate sleep-wake behavior with stress, motivation and energy balance.
Collapse
Affiliation(s)
- Anita Lüthi
- Department of Fundamental Neurosciences (DNF), University of Lausanne, Rue du Bugnon 9, CH-1005 Lausanne, Switzerland.
| |
Collapse
|
52
|
Abstract
In homeothermic animals sleep preparatory behaviours often promote thermal efficiency, including warmth-seeking, adopting particular postures (curling up, head tucking) and nest building, all promoting warmer skin microclimates. Skin warmth induces NREM sleep and body cooling via circuitry that connects skin sensation to the preoptic hypothalamus. Coupling sleep induction and lower body temperature could serve to minimise energy expenditure or allow energy reallocation. Cooling during NREM sleep may also induce transcriptional changes in genes whose products facilitate housekeeping functions or measure the time spent sleeping.
Collapse
Affiliation(s)
- Edward C Harding
- Department of Life Sciences, Imperial College London, South Kensington, SW7 2AZ, UK
| | - Nicholas P Franks
- Department of Life Sciences, Imperial College London, South Kensington, SW7 2AZ, UK.,Centre for Neurotechnology, Imperial College London, SW7 2AZ, UK.,UK Dementia Research Institute at Imperial College London, UK
| | - William Wisden
- Department of Life Sciences, Imperial College London, South Kensington, SW7 2AZ, UK.,Centre for Neurotechnology, Imperial College London, SW7 2AZ, UK.,UK Dementia Research Institute at Imperial College London, UK
| |
Collapse
|
53
|
Northeast RC, Vyazovskiy VV, Bechtold DA. Eat, sleep, repeat: the role of the circadian system in balancing sleep-wake control with metabolic need. CURRENT OPINION IN PHYSIOLOGY 2020; 15:183-191. [PMID: 32617440 PMCID: PMC7323618 DOI: 10.1016/j.cophys.2020.02.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Feeding and sleep are behaviours fundamental to survival, and as such are subject to powerful homeostatic control. Of course, these are mutually exclusive behaviours, and therefore require coordinated temporal organisation to ensure that both energy demands and sleep need are met. Under optimal conditions, foraging/feeding and sleep can be simply partitioned to appropriate phases of the circadian cycle so that they are in suitable alignment with the external environment. However, under conditions of negative energy balance, increased foraging activity must be balanced against sleep requirements and energy conservation. In mammals and many other species, neural circuits that regulate sleep and energy balance are intimately and reciprocally linked. Here, we examine this circuitry, discuss how homeostatic regulation and temporal patterning of sleep are modulated by altered food availability, and describe the role of circadian system in adaptation to metabolic stress.
Collapse
Affiliation(s)
- Rebecca C Northeast
- Centre for Biological Timing, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Vladyslav V Vyazovskiy
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - David A Bechtold
- Centre for Biological Timing, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| |
Collapse
|
54
|
Lyons DG, Rihel J. Sleep Circuits and Physiology in Non-Mammalian Systems. CURRENT OPINION IN PHYSIOLOGY 2020; 15:245-255. [PMID: 34738047 DOI: 10.1016/j.cophys.2020.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Research over the last 20 years has firmly established the existence of sleep states across the animal kingdom. Work in non-mammalian animal models such as nematodes, fruit flies, and zebrafish has now uncovered many evolutionarily conserved aspects of sleep physiology and regulation, including shared circuit architecture, homeostatic and circadian control elements, and principles linking sleep physiology to function. Non-mammalian sleep research is now shedding light on fundamental aspects of the genetic and neuronal circuit regulation of sleep, with direct implications for the understanding of how sleep is regulated in mammals.
Collapse
Affiliation(s)
- Declan G Lyons
- Department of Cell and Developmental Biology, University College London, United Kingdom, WC1E 6BT
| | - Jason Rihel
- Department of Cell and Developmental Biology, University College London, United Kingdom, WC1E 6BT
| |
Collapse
|
55
|
Activation of Preoptic GABAergic or Glutamatergic Neurons Modulates Sleep-Wake Architecture, but Not Anesthetic State Transitions. Curr Biol 2020; 30:779-787.e4. [PMID: 32084397 DOI: 10.1016/j.cub.2019.12.063] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 11/11/2019] [Accepted: 12/19/2019] [Indexed: 12/16/2022]
Abstract
The precise mechanism of general anesthesia remains unclear. In the last two decades, there has been considerable focus on the hypothesis that anesthetics co-opt the neural mechanisms regulating sleep. This hypothesis is supported by ample correlative evidence at the level of sleep-promoting nuclei, but causal investigations of potent inhaled anesthetics have not been conducted. Here, we tested the hypothesis that chemogenetic activation of discrete neuronal subpopulations within the median preoptic nucleus (MnPO) and ventrolateral preoptic nucleus (VLPO) of the hypothalamus would modulate sleep/wake states and alter the time to loss and resumption of consciousness associated with isoflurane, a potent halogenated ether in common clinical use. We show that activating MnPO/VLPO GABAergic or glutamatergic neurons does not alter anesthetic induction or recovery time. However, activation of these neuronal subpopulations did alter sleep-wake architecture. Notably, we report the novel finding that stimulation of VLPO glutamatergic neurons causes a strong increase in wakefulness. We conclude that activation of preoptic GABAergic or glutamatergic neurons that increase sleep or wakefulness does not substantively influence anesthetic state transitions. These data indicate that the correlative evidence for a mechanistic overlap of sleep and anesthesia at the level of an individual nucleus might not necessarily have strong causal significance.
Collapse
|
56
|
Barredo CG, Gil-Marti B, Deveci D, Romero NM, Martin FA. Timing the Juvenile-Adult Neurohormonal Transition: Functions and Evolution. Front Endocrinol (Lausanne) 2020; 11:602285. [PMID: 33643219 PMCID: PMC7909313 DOI: 10.3389/fendo.2020.602285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 12/28/2020] [Indexed: 02/05/2023] Open
Abstract
Puberty and metamorphosis are two major developmental transitions linked to the reproductive maturation. In mammals and vertebrates, the central brain acts as a gatekeeper, timing the developmental transition through the activation of a neuroendocrine circuitry. In addition to reproduction, these neuroendocrine axes and the sustaining genetic network play additional roles in metabolism, sleep and behavior. Although neurohormonal axes regulating juvenile-adult transition have been classically considered the result of convergent evolution (i.e., analogous) between mammals and insects, recent findings challenge this idea, suggesting that at least some neuroendocrine circuits might be present in the common bilaterian ancestor Urbilateria. The initial signaling pathways that trigger the transition in different species appear to be of a single evolutionary origin and, consequently, many of the resulting functions are conserved with a few other molecular players being co-opted during evolution.
Collapse
Affiliation(s)
- Celia G. Barredo
- Molecular Physiology of Behavior Laboratory, Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain
| | - Beatriz Gil-Marti
- Molecular Physiology of Behavior Laboratory, Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain
| | - Derya Deveci
- Sartorius Netherlands BV, Amersfoor, Netherlands
| | - Nuria M. Romero
- Developmental Timing, Environment and Behaviors Laboratory, Institut Sophia Agrobiotech, Université Côte d’Azur-INRAE-CNRS-INSERM, Sophia Antipolis, France
- *Correspondence: Nuria M. Romero, ; Francisco A. Martin,
| | - Francisco A. Martin
- Molecular Physiology of Behavior Laboratory, Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain
- *Correspondence: Nuria M. Romero, ; Francisco A. Martin,
| |
Collapse
|
57
|
Galanin peptide family regulation of glucose metabolism. Front Neuroendocrinol 2020; 56:100801. [PMID: 31705911 DOI: 10.1016/j.yfrne.2019.100801] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 10/09/2019] [Accepted: 10/25/2019] [Indexed: 12/15/2022]
Abstract
Recent preclinical and clinical studies have indicated that the galanin peptide family may regulate glucose metabolism and alleviate insulin resistance, which diminishes the probability of type 2 diabetes mellitus. The galanin was discovered in 1983 as a gut-derived peptide hormone. Subsequently, galanin peptide family was found to exert a series of metabolic effects, including the regulation of gut motility, body weight and glucose metabolism. The galanin peptide family in modulating glucose metabolism received recently increasing recognition because pharmacological activiation of galanin signaling might be of therapeutic value to improve insuin resistance and type 2 diabetes mellitus. To date, however, few papers have summarized the role of the galanin peptide family in modulating glucose metabolism and insulin resistance. In this review we summarize the metabolic effect of galanin peptide family and highlight its glucoregulatory action and discuss the pharmacological value of galanin pathway activiation for the treatment of glucose intolerance and type 2 diabetes mellitus.
Collapse
|