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Yamaguchi H. Hypothalamic control of torpor and hibernation. Temperature (Austin) 2024; 11:187-189. [PMID: 39193047 PMCID: PMC11346540 DOI: 10.1080/23328940.2024.2339794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/03/2024] [Accepted: 04/03/2024] [Indexed: 08/29/2024] Open
Affiliation(s)
- Hiroshi Yamaguchi
- Department of Neural Regulation, Research Institute of Environmental Medicine, Nagoya UniversityNagoya, Aichi, Japan
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2
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Cogut V, Goris M, Jansma A, van der Staaij M, Henning RH. Hippocampal neuroimmune response in mice undergoing serial daily torpor induced by calorie restriction. Front Neuroanat 2024; 18:1334206. [PMID: 38686173 PMCID: PMC11056553 DOI: 10.3389/fnana.2024.1334206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/11/2024] [Indexed: 05/02/2024] Open
Abstract
Hibernating animals demonstrate a remarkable ability to withstand extreme physiological brain changes without triggering adverse neuroinflammatory responses. While hibernators may offer valuable insights into the neuroprotective mechanisms inherent to hibernation, studies using such species are constrained by the limited availability of molecular tools. Laboratory mice may serve as an alternative, entering states of hypometabolism and hypothermia similar to the torpor observed in hibernation when faced with energy shortage. Notably, prolonged calorie restriction (CR) induces serial daily torpor patterns in mice, comparable to species that utilize daily hibernation. Here, we examined the neuroinflammatory response in the hippocampus of male C57BL/6 mice undergoing serial daily torpor induced by a 30% CR for 4 weeks. During daily torpor episodes, CR mice exhibited transient increases in TNF-α mRNA expression, which normalized upon arousal. Concurrently, the CA1 region of the hippocampus showed persistent morphological changes in microglia, characterized by reduced cell branching, decreased cell complexity and altered shape. Importantly, these morphological changes were not accompanied by evident signs of astrogliosis or oxidative stress, typically associated with detrimental neuroinflammation. Collectively, the adaptive nature of the brain's inflammatory response to CR-induced torpor in mice parallels observations in hibernators, highlighting its value for studying the mechanisms of brain resilience during torpor. Such insights could pave the way for novel therapeutic interventions in stroke and neurodegenerative disorders in humans.
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Affiliation(s)
- Valeria Cogut
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, Netherlands
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3
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Jayne L, Lavin-Peter A, Roessler J, Tyshkovskiy A, Antoszewski M, Ren E, Markovski A, Sun S, Yao H, Sankaran VG, Gladyshev VN, Brooke RT, Horvath S, Griffith EC, Hrvatin S. A torpor-like state (TLS) in mice slows blood epigenetic aging and prolongs healthspan. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.20.585828. [PMID: 38585858 PMCID: PMC10996477 DOI: 10.1101/2024.03.20.585828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Torpor and hibernation are extreme physiological adaptations of homeotherms associated with pro-longevity effects. Yet the underlying mechanisms of how torpor affects aging, and whether hypothermic and hypometabolic states can be induced to slow aging and increase health span, remain unknown. We demonstrate that the activity of a spatially defined neuronal population in the avMLPA, which has previously been identified as a torpor-regulating brain region, is sufficient to induce a torpor like state (TLS) in mice. Prolonged induction of TLS slows epigenetic aging across multiple tissues and improves health span. We isolate the effects of decreased metabolic rate, long-term caloric restriction, and decreased core body temperature (Tb) on blood epigenetic aging and find that the pro-longevity effect of torpor-like states is mediated by decreased Tb. Taken together, our findings provide novel mechanistic insight into the pro-longevity effects of torpor and hibernation and support the growing body of evidence that Tb is an important mediator of aging processes.
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Affiliation(s)
- Lorna Jayne
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, 455 Main Street, Cambridge, MA 02142, USA
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
- Present address: Department of Neurobiology, Stanford University Medical Center, Stanford, CA, USA
| | - Aurora Lavin-Peter
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, 455 Main Street, Cambridge, MA 02142, USA
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Julian Roessler
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, 455 Main Street, Cambridge, MA 02142, USA
| | - Alexander Tyshkovskiy
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Mateusz Antoszewski
- Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Erika Ren
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Aleksandar Markovski
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, 455 Main Street, Cambridge, MA 02142, USA
| | - Senmiao Sun
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
- Program in Neuroscience, Harvard Medical School, Boston, MA, USA
| | - Hanqi Yao
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Vijay G. Sankaran
- Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Vadim N. Gladyshev
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Steve Horvath
- Epigenetic Clock Development Foundation, Torrance, CA, USA
- Altos Labs, Cambridge, UK
| | - Eric C. Griffith
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Sinisa Hrvatin
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, 455 Main Street, Cambridge, MA 02142, USA
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4
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Clissa L, Macaluso A, Morelli R, Occhinegro A, Piscitiello E, Taddei L, Luppi M, Amici R, Cerri M, Hitrec T, Rinaldi L, Zoccoli A. Fluorescent Neuronal Cells v2: multi-task, multi-format annotations for deep learning in microscopy. Sci Data 2024; 11:184. [PMID: 38341463 PMCID: PMC10858880 DOI: 10.1038/s41597-024-03005-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 01/26/2024] [Indexed: 02/12/2024] Open
Abstract
Fluorescent Neuronal Cells v2 is a collection of fluorescence microscopy images and the corresponding ground-truth annotations, designed to foster innovative research in the domains of Life Sciences and Deep Learning. This dataset encompasses three image collections wherein rodent neuronal cell nuclei and cytoplasm are stained with diverse markers to highlight their anatomical or functional characteristics. Specifically, we release 1874 high-resolution images alongside 750 corresponding ground-truth annotations for several learning tasks, including semantic segmentation, object detection and counting. The contribution is two-fold. First, thanks to the variety of annotations and their accessible formats, we anticipate our work will facilitate methodological advancements in computer vision approaches for segmentation, detection, feature extraction, unsupervised and self-supervised learning, transfer learning, and related areas. Second, by enabling extensive exploration and benchmarking, we hope Fluorescent Neuronal Cells v2 will catalyze breakthroughs in fluorescence microscopy analysis and promote cutting-edge discoveries in life sciences.
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Affiliation(s)
- Luca Clissa
- National Institute of Nuclear Physics, Bologna, Italy.
- University of Bologna, Department of Physics and Astronomy, Bologna, Italy.
| | - Antonio Macaluso
- German Research Center for Artificial Intelligence (DFKI), Agents and Simulated Reality Department, Saarbruecken, Germany
| | - Roberto Morelli
- University of Bologna, Department of Physics and Astronomy, Bologna, Italy
| | - Alessandra Occhinegro
- University of Bologna, Department of Biomedical and Neuromotor Sciences, Bologna, Italy
| | - Emiliana Piscitiello
- University of Bologna, Department of Biomedical and Neuromotor Sciences, Bologna, Italy
| | - Ludovico Taddei
- University of Bologna, Department of Biomedical and Neuromotor Sciences, Bologna, Italy
| | - Marco Luppi
- University of Bologna, Department of Biomedical and Neuromotor Sciences, Bologna, Italy
| | - Roberto Amici
- University of Bologna, Department of Biomedical and Neuromotor Sciences, Bologna, Italy
| | - Matteo Cerri
- University of Bologna, Department of Biomedical and Neuromotor Sciences, Bologna, Italy
| | - Timna Hitrec
- University of Bologna, Department of Biomedical and Neuromotor Sciences, Bologna, Italy
| | - Lorenzo Rinaldi
- National Institute of Nuclear Physics, Bologna, Italy
- University of Bologna, Department of Physics and Astronomy, Bologna, Italy
| | - Antonio Zoccoli
- National Institute of Nuclear Physics, Bologna, Italy
- University of Bologna, Department of Physics and Astronomy, Bologna, Italy
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5
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Hare MT, Carter ME, Swoap SJ. Activation of oxytocinergic neurons enhances torpor in mice. J Comp Physiol B 2024; 194:95-104. [PMID: 38170253 DOI: 10.1007/s00360-023-01528-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Revised: 11/13/2023] [Accepted: 11/20/2023] [Indexed: 01/05/2024]
Abstract
Mus musculus enters a torpid state in response to caloric restriction in sub-thermoneutral ambient temperatures. This torpid state is characterized by an adaptive and controlled decrease in metabolic rate, heart rate, body temperature, and activity. Previous research has identified the paraventricular nucleus (PVN) within the hypothalamus, a region containing oxytocin neurons, as a location that is active during torpor onset. We hypothesized that oxytocin neurons within the PVN are part of this neural circuit and that activation of oxytocin neurons would deepen and lengthen torpor bouts. We report that activation of oxytocin neurons alone is not sufficient to induce a torpor-like state in the fed mouse, with no significant difference in body temperature or heart rate upon activation of oxytocin neurons. However, we found that activation of oxytocin neurons prior to the onset of daily torpor both deepens and lengthens the subsequent bout, with a 1.7 ± 0.4 °C lower body temperature and a 135 ± 32 min increase in length. We therefore conclude that oxytocin neurons are involved in the neural circuitry controlling daily torpor in the mouse.
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Affiliation(s)
- Maia T Hare
- Department of Biology, Williams College, Williamstown, MA, 01267, USA
- Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra Blvd, Hempstead, NY, 11549, USA
| | - Matthew E Carter
- Department of Biology, Williams College, Williamstown, MA, 01267, USA
| | - Steven J Swoap
- Department of Biology, Williams College, Williamstown, MA, 01267, USA.
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Cerri M. Torpor: A whole-brain view of the underlying neural network. Curr Biol 2024; 34:R33-R35. [PMID: 38194928 DOI: 10.1016/j.cub.2023.11.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Torpor is a physiological state with substantial translational implications. In recent years, several brain regions responsible for controlling torpor have been pinpointed. The latest research, employing comprehensive whole-brain anatomical analysis, offers insights into a broader network responsible for regulating torpor.
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Affiliation(s)
- Matteo Cerri
- Department of Biomedical and NeuroMotor Sciences, University of Bologna, 40126 Bologna, Italy; National Institute for Nuclear Physics (INFN) - Sezione Di Bologna, 40126 Bologna, Italy; Genetics and Epigenetics of Behaviour (GEB), Istituto Italiano di Tecnologia (IIT), 16163 Genova, Italy.
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7
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de Veij Mestdagh CF, Smit AB, Henning RH, van Kesteren RE. Mitochondrial Targeting against Alzheimer's Disease: Lessons from Hibernation. Cells 2023; 13:12. [PMID: 38201215 PMCID: PMC10778235 DOI: 10.3390/cells13010012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/14/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia worldwide and yet remains without effective therapy. Amongst the many proposed causes of AD, the mitochondrial cascade hypothesis is gaining attention. Accumulating evidence shows that mitochondrial dysfunction is a driving force behind synaptic dysfunction and cognitive decline in AD patients. However, therapies targeting the mitochondria in AD have proven unsuccessful so far, and out-of-the-box options, such as hibernation-derived mitochondrial mechanisms, may provide valuable new insights. Hibernators uniquely and rapidly alternate between suppression and re-activation of the mitochondria while maintaining a sufficient energy supply and without acquiring ROS damage. Here, we briefly give an overview of mitochondrial dysfunction in AD, how it affects synaptic function, and why mitochondrial targeting in AD has remained unsuccessful so far. We then discuss mitochondria in hibernation and daily torpor in mice, covering current advancements in hibernation-derived mitochondrial targeting strategies. We conclude with new ideas on how hibernation-derived dual mitochondrial targeting of both the ATP and ROS pathways may boost mitochondrial health and induce local synaptic protein translation to increase synaptic function and plasticity. Further exploration of these mechanisms may provide more effective treatment options for AD in the future.
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Affiliation(s)
- Christina F. de Veij Mestdagh
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands; (A.B.S.); (R.E.v.K.)
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands;
- Alzheimer Center Amsterdam, Amsterdam UMC Location VUmc, 1081 HV Amsterdam, The Netherlands
| | - August B. Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands; (A.B.S.); (R.E.v.K.)
| | - Robert H. Henning
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands;
| | - Ronald E. van Kesteren
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands; (A.B.S.); (R.E.v.K.)
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Yamaguchi H, Murphy KR, Fukatsu N, Sato K, Yamanaka A, de Lecea L. Dorsomedial and preoptic hypothalamic circuits control torpor. Curr Biol 2023; 33:5381-5389.e4. [PMID: 37992720 DOI: 10.1016/j.cub.2023.10.076] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/25/2023] [Accepted: 10/31/2023] [Indexed: 11/24/2023]
Abstract
Endotherms can survive low temperatures and food shortage by actively entering a hypometabolic state known as torpor. Although the decrease in metabolic rate and body temperature (Tb) during torpor is controlled by the brain, the specific neural circuits underlying these processes have not been comprehensively elucidated. In this study, we identify the neural circuits involved in torpor regulation by combining whole-brain mapping of torpor-activated neurons, cell-type-specific manipulation of neural activity, and viral tracing-based circuit mapping. We find that Trpm2-positive neurons in the preoptic area and Vgat-positive neurons in the dorsal medial hypothalamus are activated during torpor. Genetic silencing shows that the activity of either cell type is necessary to enter the torpor state. Finally, we show that these cells receive projections from the arcuate and suprachiasmatic nucleus and send projections to brain regions involved in thermoregulation. Our results demonstrate an essential role of hypothalamic neurons in the regulation of Tb and metabolic rate during torpor and identify critical nodes of the torpor regulatory network.
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Affiliation(s)
- Hiroshi Yamaguchi
- Department of Neural Regulation, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Aichi 464-8601, Japan; PRESTO, Japan Science and Technology Agency (JST), Tokyo, Japan.
| | - Keith R Murphy
- Department of Psychiatry and Behavioral Sciences, Stanford University, 1201 Welch Road, Stanford, CA 94305, USA
| | - Noriaki Fukatsu
- Department of System Biology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 464-8601, Japan; Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 464-8601, Japan
| | - Kazuhide Sato
- Institute for Advanced Research, Nagoya University, Nagoya, Aichi 466-8550, Japan
| | | | - Luis de Lecea
- Department of Psychiatry and Behavioral Sciences, Stanford University, 1201 Welch Road, Stanford, CA 94305, USA.
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Cuyutupa VR, Moser D, Diedrich V, Cheng Y, Billaud JN, Haugg E, Singer D, Bereiter-Hahn J, Herwig A, Choukér A. Blood transcriptomics mirror regulatory mechanisms during hibernation-a comparative analysis of the Djungarian hamster with other mammalian species. Pflugers Arch 2023; 475:1149-1160. [PMID: 37542567 PMCID: PMC10499953 DOI: 10.1007/s00424-023-02842-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/13/2023] [Accepted: 07/11/2023] [Indexed: 08/07/2023]
Abstract
Hibernation enables many species of the mammalian kingdom to overcome periods of harsh environmental conditions. During this physically inactive state metabolic rate and body temperature are drastically downregulated, thereby reducing energy requirements (torpor) also over shorter time periods. Since blood cells reflect the organism´s current condition, it was suggested that transcriptomic alterations in blood cells mirror the torpor-associated physiological state. Transcriptomics on blood cells of torpid and non-torpid Djungarian hamsters and QIAGEN Ingenuity Pathway Analysis (IPA) revealed key target molecules (TMIPA), which were subjected to a comparative literature analysis on transcriptomic alterations during torpor/hibernation in other mammals. Gene expression similarities were identified in 148 TMIPA during torpor nadir among various organs and phylogenetically different mammalian species. Based on TMIPA, IPA network analyses corresponded with described inhibitions of basic cellular mechanisms and immune system-associated processes in torpid mammals. Moreover, protection against damage to the heart, kidney, and liver was deduced from this gene expression pattern in blood cells. This study shows that blood cell transcriptomics can reflect the general physiological state during torpor nadir. Furthermore, the understanding of molecular processes for torpor initiation and organ preservation may have beneficial implications for humans in extremely challenging environments, such as in medical intensive care units and in space.
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Affiliation(s)
- Valeria Rojas Cuyutupa
- Laboratory of Translational Research 'Stress and Immunity', Department of Anesthesiology, LMU Hospital, Ludwig-Maximilians-Universität in Munich, Marchioninistr. 15, Munich, 81377, Germany
| | - Dominique Moser
- Laboratory of Translational Research 'Stress and Immunity', Department of Anesthesiology, LMU Hospital, Ludwig-Maximilians-Universität in Munich, Marchioninistr. 15, Munich, 81377, Germany
| | - Victoria Diedrich
- Institute of Neurobiology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Yiming Cheng
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität in Munich, Munich, Germany
- Institute for Diabetes and Obesity, Helmholtz, Munich, Neuherberg, Germany
| | | | - Elena Haugg
- Institute of Neurobiology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Dominique Singer
- Division of Neonatology and Pediatric Critical Care Medicine, University Medical Center Eppendorf, Hamburg, Germany
| | - Jürgen Bereiter-Hahn
- Institute for Cell Biology and Neurosciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Annika Herwig
- Institute of Neurobiology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
| | - Alexander Choukér
- Laboratory of Translational Research 'Stress and Immunity', Department of Anesthesiology, LMU Hospital, Ludwig-Maximilians-Universität in Munich, Marchioninistr. 15, Munich, 81377, Germany.
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Squarcio F, Hitrec T, Piscitiello E, Cerri M, Giovannini C, Martelli D, Occhinegro A, Taddei L, Tupone D, Amici R, Luppi M. Synthetic torpor triggers a regulated mechanism in the rat brain, favoring the reversibility of Tau protein hyperphosphorylation. Front Physiol 2023; 14:1129278. [PMID: 36969585 PMCID: PMC10034179 DOI: 10.3389/fphys.2023.1129278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/28/2023] [Indexed: 03/11/2023] Open
Abstract
Introduction: Hyperphosphorylated Tau protein (PPTau) is the hallmark of tauopathic neurodegeneration. During "synthetic torpor" (ST), a transient hypothermic state which can be induced in rats by the local pharmacological inhibition of the Raphe Pallidus, a reversible brain Tau hyperphosphorylation occurs. The aim of the present study was to elucidate the - as yet unknown - molecular mechanisms underlying this process, at both a cellular and systemic level. Methods: Different phosphorylated forms of Tau and the main cellular factors involved in Tau phospho-regulation were assessed by western blot in the parietal cortex and hippocampus of rats induced in ST, at either the hypothermic nadir or after the recovery of euthermia. Pro- and anti-apoptotic markers, as well as different systemic factors which are involved in natural torpor, were also assessed. Finally, the degree of microglia activation was determined through morphometry. Results: Overall, the results show that ST triggers a regulated biochemical process which can dam PPTau formation and favor its reversibility starting, unexpectedly for a non-hibernator, from the hypothermic nadir. In particular, at the nadir, the glycogen synthase kinase-β was largely inhibited in both regions, the melatonin plasma levels were significantly increased and the antiapoptotic factor Akt was significantly activated in the hippocampus early after, while a transient neuroinflammation was observed during the recovery period. Discussion: Together, the present data suggest that ST can trigger a previously undescribed latent and regulated physiological process, that is able to cope with brain PPTau formation.
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Affiliation(s)
- Fabio Squarcio
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Timna Hitrec
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Emiliana Piscitiello
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- Centre for Applied Biomedical Research—CRBA, St. Orsola Hospital, University of Bologna, Bologna, Italy
| | - Matteo Cerri
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Catia Giovannini
- Centre for Applied Biomedical Research—CRBA, St. Orsola Hospital, University of Bologna, Bologna, Italy
- Department of Experimental, Diagnostic and Specialty Medicines, University of Bologna, Bologna, Italy
| | - Davide Martelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Alessandra Occhinegro
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- Centre for Applied Biomedical Research—CRBA, St. Orsola Hospital, University of Bologna, Bologna, Italy
| | - Ludovico Taddei
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Domenico Tupone
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- Department of Neurological Surgery, Oregon Health and Science University, Portland, OR, United States
| | - Roberto Amici
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Marco Luppi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
- Centre for Applied Biomedical Research—CRBA, St. Orsola Hospital, University of Bologna, Bologna, Italy
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11
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López JM, Carballeira P, Pozo J, León-Espinosa G, Muñoz A. Hypothalamic orexinergic neuron changes during the hibernation of the Syrian hamster. Front Neuroanat 2022; 16:993421. [PMID: 36157325 PMCID: PMC9501701 DOI: 10.3389/fnana.2022.993421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 08/09/2022] [Indexed: 11/23/2022] Open
Abstract
Hibernation in small mammals is a highly regulated process with periods of torpor involving drops in body temperature and metabolic rate, as well as a general decrease in neural activity, all of which proceed alongside complex brain adaptive changes that appear to protect the brain from extreme hypoxia and low temperatures. All these changes are rapidly reversed, with no apparent brain damage occurring, during the short periods of arousal, interspersed during torpor—characterized by transitory and partial rewarming and activity, including sleep activation, and feeding in some species. The orexins are neuropeptides synthesized in hypothalamic neurons that project to multiple brain regions and are known to participate in the regulation of a variety of processes including feeding behavior, the sleep-wake cycle, and autonomic functions such as brown adipose tissue thermogenesis. Using multiple immunohistochemical techniques and quantitative analysis, we have characterized the orexinergic system in the brain of the Syrian hamster—a facultative hibernator. Our results revealed that orexinergic neurons in this species consisted of a neuronal population restricted to the lateral hypothalamic area, whereas orexinergic fibers distribute throughout the rostrocaudal extent of the brain, particularly innervating catecholaminergic and serotonergic neuronal populations. We characterized the changes of orexinergic cells in the different phases of hibernation based on the intensity of immunostaining for the neuronal activity marker C-Fos and orexin A (OXA). During torpor, we found an increase in C-Fos immunostaining intensity in orexinergic neurons, accompanied by a decrease in OXA immunostaining. These changes were accompanied by a volume reduction and a fragmentation of the Golgi apparatus (GA) as well as a decrease in the colocalization of OXA and the GA marker GM-130. Importantly, during arousal, C-Fos and OXA expression in orexinergic neurons was highest and the structural appearance and the volume of the GA along with the colocalization of OXA/GM-130 reverted to euthermic levels. We discuss the involvement of orexinergic cells in the regulation of mammalian hibernation and, in particular, the possibility that the high activation of orexinergic cells during the arousal stage guides the rewarming as well as the feeding and sleep behaviors characteristic of this phase.
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Affiliation(s)
- Jesús M. López
- Departamento de Biología Celular, Universidad Complutense, Madrid, Spain
| | - Paula Carballeira
- Departamento de Biología Celular, Universidad Complutense, Madrid, Spain
| | - Javier Pozo
- Departamento de Biología Celular, Universidad Complutense, Madrid, Spain
| | - Gonzalo León-Espinosa
- Departamento de Química y Bioquímica, Facultad de Farmacia, Universidad San Pablo-Centro de Estudios Universitarios (CEU), Madrid, Spain
| | - Alberto Muñoz
- Departamento de Biología Celular, Universidad Complutense, Madrid, Spain
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica (CTB), Universidad Politécnica de Madrid, Madrid, Spain
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- *Correspondence: Alberto Muñoz,
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12
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Ambler M, Hitrec T, Pickering A. Turn it off and on again: characteristics and control of torpor. Wellcome Open Res 2022; 6:313. [PMID: 35087956 PMCID: PMC8764563 DOI: 10.12688/wellcomeopenres.17379.2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2022] [Indexed: 11/20/2022] Open
Abstract
Torpor is a hypothermic, hypoactive, hypometabolic state entered into by a wide range of animals in response to environmental challenge. This review summarises the current understanding of torpor. We start by describing the characteristics of the wide-ranging physiological adaptations associated with torpor. Next follows a discussion of thermoregulation, control of food intake and energy expenditure, and the interactions of sleep and thermoregulation, with particular emphasis on how those processes pertain to torpor. We move on to review the evidence for the systems that control torpor entry, including both the efferent circulating factors that signal the need for torpor, and the central processes that orchestrate it. Finally, we consider how the putative circuits responsible for torpor induction integrate with the established understanding of thermoregulation under non-torpid conditions and highlight important areas of uncertainty for future studies.
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Affiliation(s)
- Michael Ambler
- School of Physiology, Pharmacology, & Neuroscience, University of Bristol, Bristol, Bristol, BS8 1TD, UK
| | - Timna Hitrec
- School of Physiology, Pharmacology, & Neuroscience, University of Bristol, Bristol, Bristol, BS8 1TD, UK
| | - Anthony Pickering
- School of Physiology, Pharmacology, & Neuroscience, University of Bristol, Bristol, Bristol, BS8 1TD, UK
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13
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Sgarbi G, Hitrec T, Amici R, Baracca A, Di Cristoforo A, Liuzzi F, Luppi M, Solaini G, Squarcio F, Zamboni G, Cerri M. Mitochondrial respiration in rats during hypothermia resulting from central drug administration. J Comp Physiol B 2022; 192:349-360. [PMID: 35001173 DOI: 10.1007/s00360-021-01421-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 11/11/2021] [Accepted: 11/22/2021] [Indexed: 11/24/2022]
Abstract
The ability to induce a hypothermia resembling that of natural torpor would be greatly beneficial in medical and non-medical fields. At present, two procedures based on central nervous pharmacological manipulation have been shown to be effective in bringing core body temperature well below 30 °C in the rat, a non-hibernator: the first, based on the inhibition of a key relay in the central thermoregulatory pathway, the other, based on the activation of central adenosine A1 receptors. Although the role of mitochondria in the activation and maintenance of torpor has been extensively studied, no data are available for centrally induced hypothermia in non-hibernators. Thus, in the present work the respiration rate of mitochondria in the liver and in the kidney of rats following the aforementioned hypothermia-inducing treatments was studied. Moreover, to have an internal control, the same parameters were assessed in a well-consolidated model, i.e., mice during fasting-induced torpor. Our results show that state 3 respiration rate, which significantly decreased in the liver of mice, was unchanged in rats. An increase of state 4 respiration rate was observed in both species, although it was not statistically significant in rats under central adenosine stimulation. Also, a significant decrease of the respiratory control ratio was detected in both species. Finally, no effects were detected in kidney mitochondria in both species. Overall, in these hypothermic conditions liver mitochondria of rats remained active and apparently ready to be re-activated to produce energy and warm up the cells. These findings can be interpreted as encouraging in view of the finalization of a translational approach to humans.
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Affiliation(s)
- Gianluca Sgarbi
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Piazza di Porta S. Donato, 2, 40126, Bologna, Italy
| | - Timna Hitrec
- Laboratory of Autonomic and Behavioral Physiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Roberto Amici
- Laboratory of Autonomic and Behavioral Physiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Alessandra Baracca
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Piazza di Porta S. Donato, 2, 40126, Bologna, Italy
| | - Alessia Di Cristoforo
- Laboratory of Autonomic and Behavioral Physiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Francesca Liuzzi
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Piazza di Porta S. Donato, 2, 40126, Bologna, Italy
| | - Marco Luppi
- Laboratory of Autonomic and Behavioral Physiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Giancarlo Solaini
- Laboratory of Biochemistry and Mitochondrial Pathophysiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Piazza di Porta S. Donato, 2, 40126, Bologna, Italy
| | - Fabio Squarcio
- Laboratory of Autonomic and Behavioral Physiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Giovanni Zamboni
- Laboratory of Autonomic and Behavioral Physiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy
| | - Matteo Cerri
- Laboratory of Autonomic and Behavioral Physiology, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Via Irnerio, 48, 40126, Bologna, Italy.
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14
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Morelli R, Clissa L, Amici R, Cerri M, Hitrec T, Luppi M, Rinaldi L, Squarcio F, Zoccoli A. Automating cell counting in fluorescent microscopy through deep learning with c-ResUnet. Sci Rep 2021; 11:22920. [PMID: 34824294 PMCID: PMC8617067 DOI: 10.1038/s41598-021-01929-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 11/03/2021] [Indexed: 02/06/2023] Open
Abstract
Counting cells in fluorescent microscopy is a tedious, time-consuming task that researchers have to accomplish to assess the effects of different experimental conditions on biological structures of interest. Although such objects are generally easy to identify, the process of manually annotating cells is sometimes subject to fatigue errors and suffers from arbitrariness due to the operator’s interpretation of the borderline cases. We propose a Deep Learning approach that exploits a fully-convolutional network in a binary segmentation fashion to localize the objects of interest. Counts are then retrieved as the number of detected items. Specifically, we introduce a Unet-like architecture, cell ResUnet (c-ResUnet), and compare its performance against 3 similar architectures. In addition, we evaluate through ablation studies the impact of two design choices, (i) artifacts oversampling and (ii) weight maps that penalize the errors on cells boundaries increasingly with overcrowding. In summary, the c-ResUnet outperforms the competitors with respect to both detection and counting metrics (respectively, \documentclass[12pt]{minimal}
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\begin{document}$$F_1$$\end{document}F1 score = 0.81 and MAE = 3.09). Also, the introduction of weight maps contribute to enhance performances, especially in presence of clumping cells, artifacts and confounding biological structures. Posterior qualitative assessment by domain experts corroborates previous results, suggesting human-level performance inasmuch even erroneous predictions seem to fall within the limits of operator interpretation. Finally, we release the pre-trained model and the annotated dataset to foster research in this and related fields.
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Affiliation(s)
- Roberto Morelli
- National Institute for Nuclear Physics, Bologna, Italy. .,Department of Physics and Astronomy, University of Bologna, Bologna, Italy.
| | - Luca Clissa
- National Institute for Nuclear Physics, Bologna, Italy.,Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Roberto Amici
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Matteo Cerri
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Timna Hitrec
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Marco Luppi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Lorenzo Rinaldi
- National Institute for Nuclear Physics, Bologna, Italy.,Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Fabio Squarcio
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Antonio Zoccoli
- National Institute for Nuclear Physics, Bologna, Italy.,Department of Physics and Astronomy, University of Bologna, Bologna, Italy
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15
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Ambler M, Hitrec T, Pickering A. Turn it off and on again: characteristics and control of torpor. Wellcome Open Res 2021; 6:313. [DOI: 10.12688/wellcomeopenres.17379.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/12/2021] [Indexed: 11/20/2022] Open
Abstract
Torpor is a hypothermic, hypoactive, hypometabolic state entered into by a wide range of animals in response to environmental challenge. This review summarises the current understanding of torpor. We start by describing the characteristics of the wide-ranging physiological adaptations associated with torpor. Next follows a discussion of thermoregulation, control of food intake and energy expenditure, and the interactions of sleep and thermoregulation, with particular emphasis on how those processes pertain to torpor. We move on to take a critical view of the evidence for the systems that control torpor entry, including both the efferent circulating factors that signal the need for torpor, and the central processes that orchestrate it. Finally, we consider how the putative circuits responsible for torpor induction integrate with the established understanding of thermoregulation under non-torpid conditions and highlight important areas of uncertainty for future studies.
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16
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Choukér A, Ngo-Anh TJ, Biesbroek R, Heldmaier G, Heppener M, Bereiter-Hahn J. European space agency's hibernation (torpor) strategy for deep space missions: Linking biology to engineering. Neurosci Biobehav Rev 2021; 131:618-626. [PMID: 34606822 DOI: 10.1016/j.neubiorev.2021.09.054] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 07/10/2021] [Accepted: 09/28/2021] [Indexed: 11/16/2022]
Abstract
Long-duration space missions to Mars will impose extreme stresses of physical and psychological nature on the crew, as well as significant logistical and technical challenges for life support and transportation. Main challenges include optimising overall mass and maintaining crew physical and mental health. These key scopes have been taken up as the baseline for a study by the European Space Agency (ESA) using its Concurrent Design Facility (CDF). It focussed on the biology of hibernation in reducing metabolism and hence stress, and its links to the infrastructure and life support. We concluded that torpor of crew members can reduce the payload with respect to oxygen, food and water but will require monitoring and artificial intelligence (AI) assisted monitoring of the crew. These studies additionally offer new potential applications for patient care on Earth. Keywords: Space flight, concurrent design facility, metabolic reduction.
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Affiliation(s)
- Alexander Choukér
- Laboratory of Translational Research "Stress and Immunity", Department of Anesthesiology, Hospital of the Ludwig-Maximilians-University, Marchioninistrasse 15, 81377, Munich, Germany
| | - Thu Jennifer Ngo-Anh
- Directorate of Human and Robotic Exploration Programmes, European Space Agency, P.O. Box 299, 2200 AG, Noordwijk, the Netherlands
| | - Robin Biesbroek
- Directorate of Technology, Engineering and Quality, European Space Agency, P.O. Box 299, 2200 AG, Noordwijk, the Netherlands
| | - Gerhard Heldmaier
- Animal Physiology, Department of Biology, Marburg University, Karl-von-Frisch-Strasse 8, 35043, Marburg, Germany
| | - Marc Heppener
- (c)/o Directorate of Human and Robotic Exploration Programmes, European Space Agency, P.O. Box 299, 2200 AG, Noordwijk, the Netherlands
| | - Jürgen Bereiter-Hahn
- Institute for Cell Biology and Neurosciences, Goethe University Frankfurt, Max-von-Lauestr. 19, D 6438, Frankfurt Am Main, Germany.
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17
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Torpor enhances synaptic strength and restores memory performance in a mouse model of Alzheimer's disease. Sci Rep 2021; 11:15486. [PMID: 34326412 PMCID: PMC8322095 DOI: 10.1038/s41598-021-94992-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 07/13/2021] [Indexed: 12/22/2022] Open
Abstract
Hibernation induces neurodegeneration-like changes in the brain, which are completely reversed upon arousal. Hibernation-induced plasticity may therefore be of great relevance for the treatment of neurodegenerative diseases, but remains largely unexplored. Here we show that a single torpor and arousal sequence in mice does not induce dendrite retraction and synapse loss as observed in seasonal hibernators. Instead, it increases hippocampal long-term potentiation and contextual fear memory. This is accompanied by increased levels of key postsynaptic proteins and mitochondrial complex I and IV proteins, indicating mitochondrial reactivation and enhanced synaptic plasticity upon arousal. Interestingly, a single torpor and arousal sequence was also sufficient to restore contextual fear memory in an APP/PS1 mouse model of Alzheimer’s disease. Our study demonstrates that torpor in mice evokes an exceptional state of hippocampal plasticity and that naturally occurring plasticity mechanisms during torpor provide an opportunity to identify unique druggable targets for the treatment of cognitive impairment.
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18
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Cerri M, Hitrec T, Luppi M, Amici R. Be cool to be far: Exploiting hibernation for space exploration. Neurosci Biobehav Rev 2021; 128:218-232. [PMID: 34144115 DOI: 10.1016/j.neubiorev.2021.03.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 03/23/2021] [Accepted: 03/26/2021] [Indexed: 01/08/2023]
Abstract
In mammals, torpor/hibernation is a state that is characterized by an active reduction in metabolic rate followed by a progressive decrease in body temperature. Torpor was successfully mimicked in non-hibernators by inhibiting the activity of neurons within the brainstem region of the Raphe Pallidus, or by activating the adenosine A1 receptors in the brain. This state, called synthetic torpor, may be exploited for many medical applications, and for space exploration, providing many benefits for biological adaptation to the space environment, among which an enhanced protection from cosmic rays. As regards the use of synthetic torpor in space, to fully evaluate the degree of physiological advantage provided by this state, it is strongly advisable to move from Earth-based experiments to 'in the field' tests, possibly on board the International Space Station.
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Affiliation(s)
- Matteo Cerri
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
| | - Timna Hitrec
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
| | - Marco Luppi
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
| | - Roberto Amici
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum -University of Bologna, Piazza di Porta S.Donato, 2 40126, Bologna, Italy.
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19
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Zhang Z, Reis FMCV, He Y, Park JW, DiVittorio JR, Sivakumar N, van Veen JE, Maesta-Pereira S, Shum M, Nichols I, Massa MG, Anderson S, Paul K, Liesa M, Ajijola OA, Xu Y, Adhikari A, Correa SM. Estrogen-sensitive medial preoptic area neurons coordinate torpor in mice. Nat Commun 2020; 11:6378. [PMID: 33311503 PMCID: PMC7732979 DOI: 10.1038/s41467-020-20050-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/12/2020] [Indexed: 12/15/2022] Open
Abstract
Homeotherms maintain a stable internal body temperature despite changing environments. During energy deficiency, some species can cease to defend their body temperature and enter a hypothermic and hypometabolic state known as torpor. Recent advances have revealed the medial preoptic area (MPA) as a key site for the regulation of torpor in mice. The MPA is estrogen-sensitive and estrogens also have potent effects on both temperature and metabolism. Here, we demonstrate that estrogen-sensitive neurons in the MPA can coordinate hypothermia and hypometabolism in mice. Selectively activating estrogen-sensitive MPA neurons was sufficient to drive a coordinated depression of metabolic rate and body temperature similar to torpor, as measured by body temperature, physical activity, indirect calorimetry, heart rate, and brain activity. Inducing torpor with a prolonged fast revealed larger and more variable calcium transients from estrogen-sensitive MPA neurons during bouts of hypothermia. Finally, whereas selective ablation of estrogen-sensitive MPA neurons demonstrated that these neurons are required for the full expression of fasting-induced torpor in both female and male mice, their effects on thermoregulation and torpor bout initiation exhibit differences across sex. Together, these findings suggest a role for estrogen-sensitive MPA neurons in directing the thermoregulatory and metabolic responses to energy deficiency.
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Affiliation(s)
- Zhi Zhang
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Fernando M C V Reis
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA
| | - Yanlin He
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
| | - Jae W Park
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Johnathon R DiVittorio
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Nilla Sivakumar
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - J Edward van Veen
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Sandra Maesta-Pereira
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA
| | - Michael Shum
- Division of Endocrinology, Department of Medicine, David Geffen School of Medicine, Los Angeles, CA, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, Los Angeles, CA, USA
| | - India Nichols
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Megan G Massa
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Shawn Anderson
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Ketema Paul
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Marc Liesa
- Division of Endocrinology, Department of Medicine, David Geffen School of Medicine, Los Angeles, CA, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Olujimi A Ajijola
- UCLA Cardiac Arrhythmia Center, Department of Medicine, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Yong Xu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Avishek Adhikari
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA
| | - Stephanie M Correa
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA.
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA.
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20
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van der Vinne V, Pothecary CA, Wilcox SL, McKillop LE, Benson LA, Kolpakova J, Tam SKE, Krone LB, Fisk AS, Wilson TS, Yamagata T, Cantley J, Vyazovskiy VV, Peirson SN. Continuous and non-invasive thermography of mouse skin accurately describes core body temperature patterns, but not absolute core temperature. Sci Rep 2020; 10:20680. [PMID: 33244132 PMCID: PMC7693264 DOI: 10.1038/s41598-020-77786-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/13/2020] [Indexed: 11/09/2022] Open
Abstract
Body temperature is an important physiological parameter in many studies of laboratory mice. Continuous assessment of body temperature has traditionally required surgical implantation of a telemeter, but this invasive procedure adversely impacts animal welfare. Near-infrared thermography provides a non-invasive alternative by continuously measuring the highest temperature on the outside of the body (Tskin), but the reliability of these recordings as a proxy for continuous core body temperature (Tcore) measurements has not been assessed. Here, Tcore (30 s resolution) and Tskin (1 s resolution) were continuously measured for three days in mice exposed to ad libitum and restricted feeding conditions. We subsequently developed an algorithm that optimised the reliability of a Tskin-derived estimate of Tcore. This identified the average of the maximum Tskin per minute over a 30-min interval as the optimal way to estimate Tcore. Subsequent validation analyses did however demonstrate that this Tskin-derived proxy did not provide a reliable estimate of the absolute Tcore due to the high between-animal variability in the relationship between Tskin and Tcore. Conversely, validation showed that Tskin-derived estimates of Tcore reliably describe temporal patterns in physiologically-relevant Tcore changes and provide an excellent measure to perform within-animal comparisons of relative changes in Tcore.
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Affiliation(s)
- Vincent van der Vinne
- Department of Physiology and Genetics, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK. .,Department of Biology, Williams College, Williamstown, MA, USA.
| | - Carina A Pothecary
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Sian L Wilcox
- Department of Physiology and Genetics, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Laura E McKillop
- Department of Physiology and Genetics, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Lindsay A Benson
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Jenya Kolpakova
- Department of Neurobiology, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Shu K E Tam
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Lukas B Krone
- Department of Physiology and Genetics, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Angus S Fisk
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Tatiana S Wilson
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Tomoko Yamagata
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - James Cantley
- Division of Systems Medicine, School of Medicine, University of Dundee, Dundee, UK
| | - Vladyslav V Vyazovskiy
- Department of Physiology and Genetics, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK
| | - Stuart N Peirson
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neurosciences Institute, University of Oxford, Oxford, UK.
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21
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Stress-induced sleep-like inactivity modulates stress susceptibility in mice. Sci Rep 2020; 10:19800. [PMID: 33188274 PMCID: PMC7666172 DOI: 10.1038/s41598-020-76717-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/28/2020] [Indexed: 11/09/2022] Open
Abstract
Severe environmental and social stress induces dysregulation of sleep along with mood and cognitive disturbances. However, the role and mechanism of this sleep dysregulation remain elusive. Here we evaluated sleep-like inactivity measured by voluntary movements and its relationship to social behaviors in mice without or with social defeat stress as well as the stressed mice with subsequent sleep deprivation. Social defeat stress immediately induced sleep-like inactivity with decreased body temperature. In the social interaction test, the control mice showed high social interest and its correlation with social sniffing intensity, the latter of which indicates positive valence of social sniffing. After the stress, these social characteristics were maintained in stress-resilient mice, but disrupted in stress-susceptible mice, leading to social avoidance. Sleep deprivation after the stress decreased social sniffing intensity along with reduced social interest, but enhanced the exploratory activity with the positive valence of social sniffing. We also found by c-Fos immunohistochemistry that the stress activated sleep-related brain regions, the dorsomedial hypothalamus and ventrolateral periaqueductal gray. Collectively, these findings show that stress activates sleep-related brain regions and induces sleep-like inactivity, contributing to multiple roles of stress-induced sleep for social behaviors.
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22
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Hrvatin S, Sun S, Wilcox OF, Yao H, Lavin-Peter AJ, Cicconet M, Assad EG, Palmer ME, Aronson S, Banks AS, Griffith EC, Greenberg ME. Neurons that regulate mouse torpor. Nature 2020; 583:115-121. [PMID: 32528180 DOI: 10.1038/s41586-020-2387-5] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 05/07/2020] [Indexed: 12/27/2022]
Abstract
The advent of endothermy, which is achieved through the continuous homeostatic regulation of body temperature and metabolism1,2, is a defining feature of mammalian and avian evolution. However, when challenged by food deprivation or harsh environmental conditions, many mammalian species initiate adaptive energy-conserving survival strategies-including torpor and hibernation-during which their body temperature decreases far below its homeostatic set-point3-5. How homeothermic mammals initiate and regulate these hypothermic states remains largely unknown. Here we show that entry into mouse torpor, a fasting-induced state with a greatly decreased metabolic rate and a body temperature as low as 20 °C6, is regulated by neurons in the medial and lateral preoptic area of the hypothalamus. We show that restimulation of neurons that were activated during a previous bout of torpor is sufficient to initiate the key features of torpor, even in mice that are not calorically restricted. Among these neurons we identify a population of glutamatergic Adcyap1-positive cells, the activity of which accurately determines when mice naturally initiate and exit torpor, and the inhibition of which disrupts the natural process of torpor entry, maintenance and arousal. Taken together, our results reveal a specific neuronal population in the mouse hypothalamus that serves as a core regulator of torpor. This work forms a basis for the future exploration of mechanisms and circuitry that regulate extreme hypothermic and hypometabolic states, and enables genetic access to monitor, initiate, manipulate and study these ancient adaptations of homeotherm biology.
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Affiliation(s)
- Sinisa Hrvatin
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
| | - Senmiao Sun
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.,Program in Neuroscience, Harvard Medical School, Boston, MA, USA
| | - Oren F Wilcox
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Hanqi Yao
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | | | - Marcelo Cicconet
- Image and Data Analysis Core, Harvard Medical School, Boston, MA, USA
| | - Elena G Assad
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | | | | | - Alexander S Banks
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Eric C Griffith
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
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23
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Takahashi TM, Sunagawa GA, Soya S, Abe M, Sakurai K, Ishikawa K, Yanagisawa M, Hama H, Hasegawa E, Miyawaki A, Sakimura K, Takahashi M, Sakurai T. A discrete neuronal circuit induces a hibernation-like state in rodents. Nature 2020; 583:109-114. [PMID: 32528181 DOI: 10.1038/s41586-020-2163-6] [Citation(s) in RCA: 123] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 03/04/2020] [Indexed: 02/07/2023]
Abstract
Hibernating mammals actively lower their body temperature to reduce energy expenditure when facing food scarcity1. This ability to induce a hypometabolic state has evoked great interest owing to its potential medical benefits2,3. Here we show that a hypothalamic neuronal circuit in rodents induces a long-lasting hypothermic and hypometabolic state similar to hibernation. In this state, although body temperature and levels of oxygen consumption are kept very low, the ability to regulate metabolism still remains functional, as in hibernation4. There was no obvious damage to tissues and organs or abnormalities in behaviour after recovery from this state. Our findings could enable the development of a method to induce a hibernation-like state, which would have potential applications in non-hibernating mammalian species including humans.
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Affiliation(s)
- Tohru M Takahashi
- Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.,International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
| | - Genshiro A Sunagawa
- Laboratory for Retinal Regeneration, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan.
| | - Shingo Soya
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
| | - Manabu Abe
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan.,Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata, Japan
| | - Katsuyasu Sakurai
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
| | - Kiyomi Ishikawa
- Laboratory for Retinal Regeneration, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Masashi Yanagisawa
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
| | - Hiroshi Hama
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako, Japan
| | - Emi Hasegawa
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
| | - Atsushi Miyawaki
- Laboratory for Cell Function Dynamics, RIKEN Center for Brain Science, Wako, Japan
| | - Kenji Sakimura
- Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata, Japan
| | - Masayo Takahashi
- Laboratory for Retinal Regeneration, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Takeshi Sakurai
- Faculty of Medicine, University of Tsukuba, Tsukuba, Japan. .,International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan. .,Life Science Center, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan.
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24
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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.
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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
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25
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Lo Martire V, Berteotti C, Bastianini S, Alvente S, Valli A, Cerri M, Amici R, Silvani A, Swoap SJ, Zoccoli G. The physiological signature of daily torpor is not orexin dependent. J Comp Physiol B 2020; 190:493-507. [DOI: 10.1007/s00360-020-01281-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/01/2020] [Accepted: 04/27/2020] [Indexed: 12/25/2022]
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