1
|
Kannen V. Food restriction heals darkness-related second brain inflammation. Cell Mol Immunol 2024:10.1038/s41423-024-01196-0. [PMID: 38969736 DOI: 10.1038/s41423-024-01196-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2024] [Accepted: 06/12/2024] [Indexed: 07/07/2024] Open
Affiliation(s)
- Vinicius Kannen
- University of Toronto, Department of Pharmacology and Toxicology, 1 King's College Cir, Toronto, ON, M5S 1A8, Canada.
| |
Collapse
|
2
|
Hoekstra MMB, Ness N, Badia-Soteras A, Brancaccio M. Bmal1 integrates circadian function and temperature sensing in the suprachiasmatic nucleus. Proc Natl Acad Sci U S A 2024; 121:e2316646121. [PMID: 38625943 PMCID: PMC11047078 DOI: 10.1073/pnas.2316646121] [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: 09/25/2023] [Accepted: 03/22/2024] [Indexed: 04/18/2024] Open
Abstract
Circadian regulation and temperature dependency are important orchestrators of molecular pathways. How the integration between these two drivers is achieved, is not understood. We monitored circadian- and temperature-dependent effects on transcription dynamics of cold-response protein RNA Binding Motif 3 (Rbm3). Temperature changes in the mammalian master circadian pacemaker, the suprachiasmatic nucleus (SCN), induced Rbm3 transcription and regulated its circadian periodicity, whereas the core clock gene Per2 was unaffected. Rbm3 induction depended on a full Brain And Muscle ARNT-Like Protein 1 (Bmal1) complement: reduced Bmal1 erased Rbm3 responses and weakened SCN circuit resilience to temperature changes. By focusing on circadian and temperature dependency, we highlight weakened transmission between core clock and downstream pathways as a potential route for reduced circadian resilience.
Collapse
Affiliation(s)
- Marieke M. B. Hoekstra
- Department of Brain Science, Imperial College London, LondonW12 0NN, United Kingdom
- Department of Brain Sciences, United Kingdom Dementia Research Institute at Imperial College London, LondonW12 0NN, United Kingdom
| | - Natalie Ness
- Department of Brain Science, Imperial College London, LondonW12 0NN, United Kingdom
- Department of Brain Sciences, United Kingdom Dementia Research Institute at Imperial College London, LondonW12 0NN, United Kingdom
| | - Aina Badia-Soteras
- Department of Brain Science, Imperial College London, LondonW12 0NN, United Kingdom
- Department of Brain Sciences, United Kingdom Dementia Research Institute at Imperial College London, LondonW12 0NN, United Kingdom
| | - Marco Brancaccio
- Department of Brain Science, Imperial College London, LondonW12 0NN, United Kingdom
- Department of Brain Sciences, United Kingdom Dementia Research Institute at Imperial College London, LondonW12 0NN, United Kingdom
| |
Collapse
|
3
|
Ono D, Weaver DR, Hastings MH, Honma KI, Honma S, Silver R. The Suprachiasmatic Nucleus at 50: Looking Back, Then Looking Forward. J Biol Rhythms 2024; 39:135-165. [PMID: 38366616 PMCID: PMC7615910 DOI: 10.1177/07487304231225706] [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] [Indexed: 02/18/2024]
Abstract
It has been 50 years since the suprachiasmatic nucleus (SCN) was first identified as the central circadian clock and 25 years since the last overview of developments in the field was published in the Journal of Biological Rhythms. Here, we explore new mechanisms and concepts that have emerged in the subsequent 25 years. Since 1997, methodological developments, such as luminescent and fluorescent reporter techniques, have revealed intricate relationships between cellular and network-level mechanisms. In particular, specific neuropeptides such as arginine vasopressin, vasoactive intestinal peptide, and gastrin-releasing peptide have been identified as key players in the synchronization of cellular circadian rhythms within the SCN. The discovery of multiple oscillators governing behavioral and physiological rhythms has significantly advanced our understanding of the circadian clock. The interaction between neurons and glial cells has been found to play a crucial role in regulating these circadian rhythms within the SCN. Furthermore, the properties of the SCN network vary across ontogenetic stages. The application of cell type-specific genetic manipulations has revealed components of the functional input-output system of the SCN and their correlation with physiological functions. This review concludes with the high-risk effort of identifying open questions and challenges that lie ahead.
Collapse
Affiliation(s)
- Daisuke Ono
- Stress Recognition and Response, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - David R Weaver
- Department of Neurobiology and NeuroNexus Institute, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Michael H Hastings
- Division of Neurobiology, MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Ken-Ichi Honma
- Research and Education Center for Brain Science, Hokkaido University, Sapporo, Japan
- Center for Sleep and Circadian Rhythm Disorders, Sapporo Hanazono Hospital, Sapporo, Japan
| | - Sato Honma
- Research and Education Center for Brain Science, Hokkaido University, Sapporo, Japan
- Center for Sleep and Circadian Rhythm Disorders, Sapporo Hanazono Hospital, Sapporo, Japan
| | - Rae Silver
- Stress Recognition and Response, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Department of Neuroscience & Behavior, Barnard College and Department of Psychology, Columbia University, New York City, New York, USA
| |
Collapse
|
4
|
Fernández-Martínez J, Ramírez-Casas Y, Aranda-Martínez P, López-Rodríguez A, Sayed RKA, Escames G, Acuña-Castroviejo D. iMS-Bmal1 -/- mice show evident signs of sarcopenia that are counteracted by exercise and melatonin therapies. J Pineal Res 2024; 76:e12912. [PMID: 37702245 DOI: 10.1111/jpi.12912] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 08/29/2023] [Accepted: 08/31/2023] [Indexed: 09/14/2023]
Abstract
Sarcopenia is an age-related disease characterized by a reduction in muscle mass, strength, and function and, therefore, a deterioration in skeletal muscle health and frailty. Although the cause of sarcopenia is still unknown and, thus, there is no treatment, increasing evidence suggests that chronodisruption, particularly alterations in Bmal1 clock gene, can lead to those deficits culminating in sarcopenia. To gain insight into the cause and mechanism of sarcopenia and the protective effect of a therapeutic intervention with exercise and/or melatonin, the gastrocnemius muscles of male and female skeletal muscle-specific and inducible Bmal1 knockout mice (iMS-Bmal1-/- ) were examined by phenotypic tests and light and electron microscopy. Our results revealed a disruption of the normal activity/rest rhythm, a drop in skeletal muscle function and mass, and increased frailty in male and female iMS-Bmal1-/- animals compared to controls. A reduction in muscle fiber size and increased collagenous tissue were also detected, accompanied by reduced mitochondrial oxidative capacity and a compensatory shift towards a more oxidative fiber type. Electron microscopy further supports mitochondrial impairment in mutant mice. Melatonin and exercise ameliorated the damage caused by loss of Bmal1 in mutant mice, except for mitochondrial damage, which was worsened by the latter. Thus, iMS-Bmal1-/- mice let us to identify Bmal1 deficiency as the responsible for the appearance of sarcopenia in the gastrocnemius muscle. Moreover, the results support the exercise and melatonin as therapeutic tools to counteract sarcopenia, by a mechanism that does not require the presence of Bmal1.
Collapse
Grants
- PI19-01372 Instituto de Salud Carlos III
- CB/10/00238 Instituto de Salud Carlos III
- CTS-101 Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía
- P18-RT-3222 Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía
- P18-RT-698 Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía
- Ministerio de Educación, Spain
Collapse
Affiliation(s)
- José Fernández-Martínez
- Centro de Investigación Biomédica, Facultad de Medicina, Departamento de Fisiología, Instituto de Biotecnología, Parque Tecnológico de Ciencias de la Salud, Universidad de Granada, Granada, Spain
- Instituto de Investigación Biosanitaria (Ibs.Granada), Hospital Universitario San Cecilio, Granada, Spain
| | - Yolanda Ramírez-Casas
- Centro de Investigación Biomédica, Facultad de Medicina, Departamento de Fisiología, Instituto de Biotecnología, Parque Tecnológico de Ciencias de la Salud, Universidad de Granada, Granada, Spain
- Instituto de Investigación Biosanitaria (Ibs.Granada), Hospital Universitario San Cecilio, Granada, Spain
| | - Paula Aranda-Martínez
- Centro de Investigación Biomédica, Facultad de Medicina, Departamento de Fisiología, Instituto de Biotecnología, Parque Tecnológico de Ciencias de la Salud, Universidad de Granada, Granada, Spain
- Instituto de Investigación Biosanitaria (Ibs.Granada), Hospital Universitario San Cecilio, Granada, Spain
| | - Alba López-Rodríguez
- Centro de Investigación Biomédica, Facultad de Medicina, Departamento de Fisiología, Instituto de Biotecnología, Parque Tecnológico de Ciencias de la Salud, Universidad de Granada, Granada, Spain
- Instituto de Investigación Biosanitaria (Ibs.Granada), Hospital Universitario San Cecilio, Granada, Spain
| | - Ramy K A Sayed
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Sohag University, Sohag, Egypt
| | - Germaine Escames
- Centro de Investigación Biomédica, Facultad de Medicina, Departamento de Fisiología, Instituto de Biotecnología, Parque Tecnológico de Ciencias de la Salud, Universidad de Granada, Granada, Spain
- Instituto de Investigación Biosanitaria (Ibs.Granada), Hospital Universitario San Cecilio, Granada, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), ISCIII, Valencia, Spain
| | - Darío Acuña-Castroviejo
- Centro de Investigación Biomédica, Facultad de Medicina, Departamento de Fisiología, Instituto de Biotecnología, Parque Tecnológico de Ciencias de la Salud, Universidad de Granada, Granada, Spain
- Instituto de Investigación Biosanitaria (Ibs.Granada), Hospital Universitario San Cecilio, Granada, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), ISCIII, Valencia, Spain
- UGC de Laboratorios Clínicos, Hospital Universitario San Cecilio, Granada, Spain
| |
Collapse
|
5
|
Elberling F, Spulber S, Bose R, Keung HY, Ahola V, Zheng Z, Ceccatelli S. Sex Differences in Long-term Outcome of Prenatal Exposure to Excess Glucocorticoids-Implications for Development of Psychiatric Disorders. Mol Neurobiol 2023; 60:7346-7361. [PMID: 37561236 PMCID: PMC10657788 DOI: 10.1007/s12035-023-03522-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 07/18/2023] [Indexed: 08/11/2023]
Abstract
Exposure to prenatal insults, such as excess glucocorticoids (GC), may lead to pathological outcomes, including neuropsychiatric disorders. The aim of the present study was to investigate the long-term effects of in utero exposure to the synthetic GC analog dexamethasone (Dex) in adult female offspring. We monitored spontaneous activity in the home cage under a constant 12 h/12 h light/dark cycle, as well as the changes following a 6-h advance of dark onset (phase shift). For comparison, we re-analysed data previously recorded in males. Dex-exposed females were spontaneously more active, and the activity onset re-entrained slower than in controls. In contrast, Dex-exposed males were less active, and the activity onset re-entrained faster than in controls. Following the phase shift, control females displayed a transient reorganisation of behaviour in light and virtually no change in dark, while Dex-exposed females showed limited variations from baseline in both light and dark, suggesting weaker photic entrainment. Next, we ran bulk RNA-sequencing in the suprachiasmatic nucleus (SCN) of Dex and control females. SPIA pathway analysis of ~ 2300 differentially expressed genes identified significantly downregulated dopamine signalling, and upregulated glutamate and GABA signalling. We selected a set of candidate genes matching the behaviour alterations and found consistent differential regulation for ~ 73% of tested genes in SCN and hippocampus tissue samples. Taken together, our data highlight sex differences in the outcome of prenatal exposure to excess GC in adult mice: in contrast to depression-like behaviour in males, the phenotype in females, defined by behaviour and differential gene expression, is consistent with ADHD models.
Collapse
Affiliation(s)
- Frederik Elberling
- Department of Neuroscience, Karolinska Institutet, Biomedicum, Solnavägen 9, 171 77, Stockholm, Sweden
| | - Stefan Spulber
- Department of Neuroscience, Karolinska Institutet, Biomedicum, Solnavägen 9, 171 77, Stockholm, Sweden.
| | - Raj Bose
- Department of Neuroscience, Karolinska Institutet, Biomedicum, Solnavägen 9, 171 77, Stockholm, Sweden
| | - Hoi Yee Keung
- Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet, 15W Science and Technology W Ave, Sha Tin, Hong Kong Special Administrative Region, People's Republic of China
| | - Virpi Ahola
- Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet, 15W Science and Technology W Ave, Sha Tin, Hong Kong Special Administrative Region, People's Republic of China
| | - Zongli Zheng
- Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet, 15W Science and Technology W Ave, Sha Tin, Hong Kong Special Administrative Region, People's Republic of China
| | - Sandra Ceccatelli
- Department of Neuroscience, Karolinska Institutet, Biomedicum, Solnavägen 9, 171 77, Stockholm, Sweden
| |
Collapse
|
6
|
Murdoch SÓ, Aiello EM, Doyle FJ. Pharmacokinetic Model-Based Control across the Blood-Brain Barrier for Circadian Entrainment. Int J Mol Sci 2023; 24:14830. [PMID: 37834278 PMCID: PMC10573769 DOI: 10.3390/ijms241914830] [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: 08/30/2023] [Revised: 09/28/2023] [Accepted: 09/29/2023] [Indexed: 10/15/2023] Open
Abstract
The ability to shift circadian phase in vivo has the potential to offer substantial health benefits. However, the blood-brain barrier prevents the absorption of the majority of large and many small molecules, posing a challenge to neurological pharmaceutical development. Motivated by the presence of the circadian molecule KL001, which is capable of causing phase shifts in a circadian oscillator, we investigated the pharmacokinetics of different neurological pharmaceuticals on the dynamics of circadian phase. Specifically, we developed and validated five different transport models that describe drug concentration profiles of a circadian pharmaceutical at the brain level under oral administration and designed a nonlinear model predictive control (MPC)-based framework for phase resetting. Performance of the novel control algorithm based on the identified pharmacokinetic models was demonstrated through simulations of real-world misalignment scenarios due to jet lag. The time to achieve a complete phase reset for 11-h phase delay ranged between 48 and 72 h, while a 5-h phase advance was compensated in 30 to 60 h. This approach provides mechanistic insight into the underlying structure of the circadian oscillatory system and thus leads to a better understanding of the feasibility of therapeutic manipulations of the system.
Collapse
Affiliation(s)
- Síofra Ó. Murdoch
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Boston, MA 02134, USA; (S.Ó.M.); (E.M.A.)
| | - Eleonora M. Aiello
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Boston, MA 02134, USA; (S.Ó.M.); (E.M.A.)
- Sansum Diabetes Research Institute, Santa Barbara, CA 93105, USA
| | - Francis J. Doyle
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Boston, MA 02134, USA; (S.Ó.M.); (E.M.A.)
- Sansum Diabetes Research Institute, Santa Barbara, CA 93105, USA
| |
Collapse
|
7
|
Richardson MES, Browne CA, Mazariegos CIH. Reversible suppression of circadian-driven locomotor rhythms in mice using a gradual fragmentation of the day-night cycle. Sci Rep 2023; 13:14423. [PMID: 37660212 PMCID: PMC10475134 DOI: 10.1038/s41598-023-41029-0] [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: 11/28/2022] [Accepted: 08/21/2023] [Indexed: 09/04/2023] Open
Abstract
Circadian rhythms are regulated by molecular clockwork and drive 24-h behaviors such as locomotor activity, which can be rendered non-functional through genetic knockouts of clock genes. Circadian rhythms are robust in constant darkness (DD) but are modulated to become exactly 24 h by the external day-night cycle. Whether ill-timed light and dark exposure can render circadian behaviors non-functional to the extent of genetic knockouts is less clear. In this study, we discovered an environmental approach that led to a reduction or lack in rhythmic 24-h-circadian wheel-running locomotor behavior in mice (referred to as arrhythmicity). We first observed behavioral circadian arrhythmicity when mice were gradually exposed to a previously published disruptive environment called the fragmented day-night cycle (FDN-G), while maintaining activity alignment with the four dispersed fragments of darkness. Remarkably, upon exposure to constant darkness (DD) or constant light (LL), FDN-G mice lost any resemblance to the FDN-G-only phenotype and instead, exhibited sporadic activity bursts. Circadian rhythms are maintained in control mice with sudden FDN exposure (FDN-S) and fully restored in FDN-G mice either spontaneously in DD or after 12 h:12 h light-dark exposure. This is the first study to generate a light-dark environment that induces reversible suppression of circadian locomotor rhythms in mice.
Collapse
Affiliation(s)
- Melissa E S Richardson
- Department of Biological Sciences, Oakwood University, 7000 Adventist Blvd., Huntsville, AL, 35896, USA.
| | - Chérie-Akilah Browne
- Department of Biological Sciences, Oakwood University, 7000 Adventist Blvd., Huntsville, AL, 35896, USA
| | | |
Collapse
|
8
|
Ono D, Wang H, Hung CJ, Wang HT, Kon N, Yamanaka A, Li Y, Sugiyama T. Network-driven intracellular cAMP coordinates circadian rhythm in the suprachiasmatic nucleus. SCIENCE ADVANCES 2023; 9:eabq7032. [PMID: 36598978 DOI: 10.1126/sciadv.abq7032] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
The mammalian central circadian clock, located in the suprachiasmatic nucleus (SCN), coordinates the timing of physiology and behavior to local time cues. In the SCN, second messengers, such as cAMP and Ca2+, are suggested to be involved in the input and/or output of the molecular circadian clock. However, the functional roles of second messengers and their dynamics in the SCN remain largely unclear. In the present study, we visualized the spatiotemporal patterns of circadian rhythms of second messengers and neurotransmitter release in the SCN. Here, we show that neuronal activity regulates the rhythmic release of vasoactive intestinal peptides from the SCN, which drives the circadian rhythms of intracellular cAMP in the SCN. Furthermore, optical manipulation of intracellular cAMP levels in the SCN shifts molecular and behavioral circadian rhythms. Together, our study demonstrates that intracellular cAMP is a key molecule in the organization of the SCN circadian neuronal network.
Collapse
Affiliation(s)
- Daisuke Ono
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Huan Wang
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Chi Jung Hung
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Hsin-Tzu Wang
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Laboratory of Animal Integrative Physiology, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Department of Biological Sciences, School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Naohiro Kon
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Laboratory of Animal Integrative Physiology, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Akihiro Yamanaka
- Chinese Institute for Brain Research (CIBR), Beijing, 102206, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Takashi Sugiyama
- Advanced Optics and Biological Engineering, Evident Corporation, Tokyo, Japan
| |
Collapse
|
9
|
Galinde AAS, Al-Mughales F, Oster H, Heyde I. Different levels of circadian (de)synchrony -- where does it hurt? F1000Res 2022; 11:1323. [PMID: 37125019 PMCID: PMC10130703 DOI: 10.12688/f1000research.127234.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/24/2022] [Indexed: 11/16/2022] Open
Abstract
A network of cellular timers ensures the maintenance of homeostasis by temporal modulation of physiological processes across the day. These so-called circadian clocks are synchronized to geophysical time by external time cues (or zeitgebers). In modern societies, natural environmental cycles are disrupted by artificial lighting, around-the-clock availability of food or shiftwork. Such contradictory zeitgeber input promotes chronodisruption, i.e., the perturbation of internal circadian rhythms, resulting in adverse health outcomes. While this phenomenon is well described, it is still poorly understood at which level of organization perturbed rhythms impact on health and wellbeing. In this review, we discuss different levels of chronodisruption and what is known about their health effects. We summarize the results of disrupted phase coherence between external and internal time vs. misalignment of tissue clocks amongst each other, i.e., internal desynchrony. Last, phase incoherence can also occur at the tissue level itself. Here, alterations in phase coordination can emerge between cellular clocks of the same tissue or between different clock genes within the single cell. A better understanding of the mechanisms of circadian misalignment and its effects on physiology will help to find effective tools to prevent or treat disorders arising from modern-day chronodisruptive environments.
Collapse
Affiliation(s)
- Ankita AS. Galinde
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
| | - Faheem Al-Mughales
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
- Biochemistry Department, Faculty of Medicine and Health Sciences, Taiz University, Taiz, Yemen
| | - Henrik Oster
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
| | - Isabel Heyde
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
| |
Collapse
|
10
|
Galinde AAS, Al-Mughales F, Oster H, Heyde I. Different levels of circadian (de)synchrony -- where does it hurt? F1000Res 2022; 11:1323. [PMID: 37125019 PMCID: PMC10130703 DOI: 10.12688/f1000research.127234.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/15/2023] [Indexed: 04/05/2023] Open
Abstract
A network of cellular timers ensures the maintenance of homeostasis by temporal modulation of physiological processes across the day. These so-called circadian clocks are synchronized to geophysical time by external time cues (or zeitgebers). In modern societies, natural environmental cycles are disrupted by artificial lighting, around-the-clock availability of food or shift work. Such contradictory zeitgeber input promotes chronodisruption, i.e., the perturbation of internal circadian rhythms, resulting in adverse health outcomes. While this phenomenon is well described, it is still poorly understood at which level of organization perturbed rhythms impact on health and wellbeing. In this review, we discuss different levels of chronodisruption and what is known about their health effects. We summarize the results of disrupted phase coherence between external and internal time vs. misalignment of tissue clocks amongst each other, i.e., internal desynchrony. Last, phase incoherence can also occur at the tissue level itself. Here, alterations in phase coordination can emerge between cellular clocks of the same tissue or between different clock genes within the single cell. A better understanding of the mechanisms of circadian misalignment and its effects on physiology will help to find effective tools to prevent or treat disorders arising from modern-day chronodisruptive environments.
Collapse
Affiliation(s)
- Ankita AS. Galinde
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
| | - Faheem Al-Mughales
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
- Biochemistry Department, Faculty of Medicine and Health Sciences, Taiz University, Taiz, Yemen
| | - Henrik Oster
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
| | - Isabel Heyde
- Institute of Neurobiology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, 23562, Germany
| |
Collapse
|
11
|
Morioka E, Kasuga Y, Kanda Y, Moritama S, Koizumi H, Yoshikawa T, Miura N, Ikeda M, Higashida H, Holmes TC, Ikeda M. Mitochondrial LETM1 drives ionic and molecular clock rhythms in circadian pacemaker neurons. Cell Rep 2022; 39:110787. [PMID: 35545046 DOI: 10.1016/j.celrep.2022.110787] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/14/2022] [Accepted: 04/14/2022] [Indexed: 11/18/2022] Open
Abstract
The mechanisms that generate robust ionic oscillation in circadian pacemaker neurons are under investigation. Here, we demonstrate critical functions of the mitochondrial cation antiporter leucine zipper-EF-hand-containing transmembrane protein 1 (LETM1), which exchanges K+/H+ in Drosophila and Ca2+/H+ in mammals, in circadian pacemaker neurons. Letm1 knockdown in Drosophila pacemaker neurons reduced circadian cytosolic H+ rhythms and prolonged nuclear PERIOD/TIMELESS expression rhythms and locomotor activity rhythms. In rat pacemaker neurons in the hypothalamic suprachiasmatic nucleus (SCN), circadian rhythms in cytosolic Ca2+ and Bmal1 transcription were dampened by Letm1 knockdown. Mitochondrial Ca2+ uptake peaks late during the day were also observed in rat SCN neurons following photolytic elevation of cytosolic Ca2+. Since cation transport by LETM1 is coupled to mitochondrial energy synthesis, we propose that LETM1 integrates metabolic, ionic, and molecular clock rhythms in the central clock system in both invertebrates and vertebrates.
Collapse
Affiliation(s)
- Eri Morioka
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama 930-8555, Japan
| | - Yusuke Kasuga
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama 930-8555, Japan
| | - Yuzuki Kanda
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama 930-8555, Japan
| | - Saki Moritama
- Graduate School of Science and Engineering, University of Toyama, Gofuku, Toyama 930-8555, Japan
| | - Hayato Koizumi
- Graduate School of Innovative Life Science, University of Toyama, Gofuku, Toyama 930-8555, Japan
| | - Tomoko Yoshikawa
- Organization for International Education and Exchange, University of Toyama, Toyama 930-8555, Japan
| | - Nobuhiko Miura
- Department of Health Medicine, Yokohama University of Pharmacy, Yokohama, Kanagawa 245-0061, Japan
| | - Masaaki Ikeda
- Department of Physiology, Faculty of Medicine, Saitama Medical University, Saitama 350-0495, Japan
| | - Haruhiro Higashida
- Research Center for Child Mental Development, Kanazawa University, Ishikawa 920-8640, Japan
| | - Todd C Holmes
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA 92697, USA
| | - Masayuki Ikeda
- Graduate School of Innovative Life Science, University of Toyama, Gofuku, Toyama 930-8555, Japan; Organization for International Education and Exchange, University of Toyama, Toyama 930-8555, Japan.
| |
Collapse
|
12
|
Abstract
Experiments that compare rhythmic properties across different genetic alterations and entrainment conditions underlie some of the most important breakthroughs in circadian biology. A robust estimation of the rhythmic properties of the circadian signals goes hand in hand with these discoveries. Widely applied traditional signal analysis methods such as fitting cosine functions or Fourier transformations rely on the assumption that oscillation periods do not change over time. However, novel high-resolution recording techniques have shown that, most commonly, circadian signals exhibit time-dependent changes of periods and amplitudes which cannot be captured with the traditional approaches. In this chapter we introduce a method to determine time-dependent properties of oscillatory signals, using the novel open-source Python-based Biological Oscillations Analysis Toolkit (pyBOAT). We show with examples how to detect rhythms, compute and interpret high-resolution time-dependent spectral results, analyze the main oscillatory component, and to subsequently determine these main components' time-dependent instantaneous period, amplitude, and phase. We introduce step-by-step how such an analysis can be done by means of the easy-to-use point-and-click graphical user interface (GUI) provided by pyBOAT or executed within a Python programming environment. Concepts are explained using simulated signals as well as experimentally obtained time series.
Collapse
Affiliation(s)
- Christoph Schmal
- Institute for Theoretical Biology, Humboldt Universität zu Berlin, Berlin, Germany.
| | - Gregor Mönke
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Adrián E Granada
- Charité Comprehensive Cancer Center, Charité Universitätsmedizin Berlin, Berlin, Germany
- German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
| |
Collapse
|
13
|
Hamada K, Ishii Y, Yoshida Y, Nakaya M, Sato Y, Kanai M, Kikuchi Y, Yamaguchi T, Iijima N, Sutherland K, Hamada T. The analysis of Period1 gene expression in vivo and in vitro using a micro PMT system. Biochem Biophys Res Commun 2021; 577:64-70. [PMID: 34507067 DOI: 10.1016/j.bbrc.2021.08.084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 08/27/2021] [Indexed: 11/29/2022]
Abstract
To detect a small amount of Period1 (Per1) expression, we developed a micro-photomultiplier tube (μPMT) system which can be used both in vivo and in vitro. Using this system, we succeeded in detecting Per1 gene expression in the skin of freely moving mice over 240 times higher compared with that of the tissue contact optical sensor (TCS) as previously reported. For in vitro studies, we succeeded in detecting elevated Per1 expression by streptozotocin (STZ) treatment in the scalp hairs at an early stage of diabetes, when glucose content in the blood was still normal. In addition, we could detect elevated Per1 expression in a single whisker hair at the time of diabetes onset. These results show that our μPMT system responds to minute changes in gene expression in freely moving mice in vivo and in mice hair follicles in vitro. Furthermore, Per1 in the hair can be used for a marker of diabetic aggravation.
Collapse
Affiliation(s)
- Kazuko Hamada
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan
| | - Yuki Ishii
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan
| | - Yukina Yoshida
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan
| | - Mizuki Nakaya
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan
| | - Yusuke Sato
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan
| | - Megumi Kanai
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan
| | - Yoshihiro Kikuchi
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan
| | - Takeshi Yamaguchi
- Center for Basic Medical Research, International University of Health and Welfare, Ohtawara, Tochigi, Japan
| | - Norio Iijima
- Center for Basic Medical Research, International University of Health and Welfare, Ohtawara, Tochigi, Japan
| | - Kenneth Sutherland
- Global Center for Biomedical Science and Engineering, Hokkaido University, Sapporo, Hokkaido, 060-8012, Japan
| | - Toshiyuki Hamada
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Ohtawara, Tochigi, 324-8501, Japan; Department of Biological Response and Regulation, Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido, 060-0812, Japan; Hakujikai Institute of Gerontology, 5-11-1, Shikahama, Adachi Ward, Tokyo, 123-0864, Japan.
| |
Collapse
|
14
|
Time-Restricted Feeding in Mice Prevents the Disruption of the Peripheral Circadian Clocks and Its Metabolic Impact during Chronic Jetlag. Nutrients 2021; 13:nu13113846. [PMID: 34836101 PMCID: PMC8622682 DOI: 10.3390/nu13113846] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/25/2021] [Accepted: 10/27/2021] [Indexed: 01/17/2023] Open
Abstract
We used time-restricted feeding (TRF) to investigate whether microbial metabolites and the hunger hormone ghrelin can become the dominant entraining factor during chronic jetlag to prevent disruption of the master and peripheral clocks, in order to promote health. Therefore, hypothalamic clock gene and Agrp/Npy mRNA expression were measured in mice that were either chronically jetlagged and fed ad libitum, jetlagged and fed a TRF diet, or not jetlagged and fed a TRF diet. Fecal short-chain fatty acid (SCFA) concentrations, plasma ghrelin and corticosterone levels, and colonic clock gene mRNA expression were measured. Preventing the disruption of the food intake pattern during chronic jetlag using TRF restored the rhythmicity in hypothalamic clock gene mRNA expression of Reverbα but not of Arntl. TRF countered the changes in plasma ghrelin levels and in hypothalamic Npy mRNA expression induced by chronic jetlag, thereby reestablishing the food intake pattern. Increase in body mass induced by chronic jetlag was prevented. Alterations in diurnal fluctuations in fecal SCFAs during chronic jetlag were prevented thereby re-entraining the rhythmic expression of peripheral clock genes. In conclusion, TRF during chronodisruption re-entrains the rhythms in clock gene expression and signals from the gut that regulate food intake to normalize body homeostasis.
Collapse
|
15
|
Modulation of circadian clock by crude drug extracts used in Japanese Kampo medicine. Sci Rep 2021; 11:21038. [PMID: 34702865 PMCID: PMC8548592 DOI: 10.1038/s41598-021-00499-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/11/2021] [Indexed: 11/08/2022] Open
Abstract
Circadian rhythm is an approximately 24 h endogenous biological rhythm. Chronic disruption of the circadian clock leads to an increased risk of diabetes, cardiovascular disease, and cancer. Hence, it is important to develop circadian clock modulators. Natural organisms are a good source of several medicines currently in use. Crude drugs used in Japanese traditional Kampo medicine or folk medicines are an excellent source for drug discovery. Furthermore, identifying new functions for existing drugs, known as the drug repositioning approach, is a popular and powerful tool. In this study, we screened 137 crude drug extracts to act as circadian clock modulators in human U2OS cells stably expressing the clock reporter Bmal1-dLuc, and approximately 12% of these modulated the circadian rhythm. We further examined the effects of several crude drugs in Rat-1 fibroblasts stably expressing Per2-luc, explant culture of lung from Per2::Luciferase knockin mice, and zebrafish larvae in vivo. Notably, more than half of the major ingredients of these crude drugs were reported to target AKT and its relevant signaling pathways. As expected, analysis of the major ingredients targeting AKT signaling confirmed the circadian clock-modulating effects. Furthermore, activator and inhibitor of AKT, and triple knockdown of AKT isoforms by siRNA also modulated the circadian rhythm. This study, by employing the drug repositioning approach, shows that Kampo medicines are a useful source for the identification of underlying mechanisms of circadian clock modulators and could potentially be used in the treatment of circadian clock disruption.
Collapse
|
16
|
Wei Z, Yang M, Feng M, Wu Z, Rosin-Arbesfeld R, Dong J, Zhu D. Inhibition of BCL9 Modulates the Cellular Landscape of Tumor-Associated Macrophages in the Tumor Immune Microenvironment of Colorectal Cancer. Front Pharmacol 2021; 12:713331. [PMID: 34566638 PMCID: PMC8461101 DOI: 10.3389/fphar.2021.713331] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 08/20/2021] [Indexed: 01/01/2023] Open
Abstract
Tumor-associated macrophages (TAMs) are an indispensable part of the tumor microenvironment (TME), and they likely play a negative rather than positive role in cancer treatment. However, the cellular landscape and transcriptional profile regulation of TAMs in the case of tumor gene inactivation or chemical interference remains unclear. The B-cell lymphoma 9/B-cell lymphoma 9-like (BCL9/BCL9L) is a critical transcription co-factor of β-catenin. Suppression of Bcl9 inhibits tumor growth in mouse models of colorectal cancer (CRC). Here, we studied the TAMs of CRC by single-cell sequencing. Bcl9 depletion caused macrophage polarization inhibition from M0 to M2 and changed the CRC TME, which further interferes with the inflammation of M0 and M1. The transcription factor regulating these processes may be related to the Wnt signaling pathway from multiple levels. Furthermore, we also found that the cells delineated from monocyte to NK-like non-functioning cells were significantly different in the BCL9-deprived population. Combining these data, we proposed a TAM-to-NK score to evaluate the dynamic balance in TME of monocyte/TAM cells and NK-like non-functioning cells in The Cancer Genome Atlas (TCGA) clinical samples to verify the clinical significance. We demonstrated that the cell type balance and transcription differences of TAMs regulated by BCL9-driven Wnt signaling affected immune surveillance and inflammation of cancer, ultimately affecting patients' prognosis. We thereby highlighted the potential of targeting Wnt signaling pathway through cancer immunotherapy.
Collapse
Affiliation(s)
- Zhuang Wei
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,Key Laboratory of Systems Biology, Innovation Center for Cell Signaling Network, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Mengxuan Yang
- Minhang Branch, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Mei Feng
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Zhongen Wu
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Rina Rosin-Arbesfeld
- Department of Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Jibin Dong
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai, China
| | - Di Zhu
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,Key Laboratory of Smart Drug Delivery, State Key Laboratory of Molecular Engineering of Polymers, School of Pharmacy, Ministry of Education, Fudan University, Shanghai, China.,Shanghai Engineering Research Center of ImmunoTherapeutics, Fudan University, Shanghai, China
| |
Collapse
|
17
|
Plante AE, Rao VP, Rizzo MA, Meredith AL. Comparative Ca 2+ channel contributions to intracellular Ca 2+ levels in the circadian clock. BIOPHYSICAL REPORTS 2021; 1:100005. [PMID: 35330949 PMCID: PMC8942421 DOI: 10.1016/j.bpr.2021.100005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/08/2021] [Indexed: 11/22/2022]
Abstract
Circadian rhythms in mammals are coordinated by the central clock in the brain, located in the suprachiasmatic nucleus (SCN). Multiple molecular and cellular signals display a circadian variation within SCN neurons, including intracellular Ca2+, but the mechanisms are not definitively established. SCN cytosolic Ca2+ levels exhibit a peak during the day, when both action potential firing and Ca2+ channel activity are increased, and are decreased at night, correlating with a reduction in firing rate. In this study, we employ a single-color fluorescence anisotropy reporter (FLARE), Venus FLARE-Cameleon, and polarization inverted selective-plane illumination microscopy to measure rhythmic changes in cytosolic Ca2+ in SCN neurons. Using this technique, the Ca2+ channel subtypes contributing to intracellular Ca2+ at the peak and trough of the circadian cycle were assessed using a pharmacological approach with Ca2+ channel inhibitors. Peak (218 ± 16 nM) and trough (172 ± 13 nM) Ca2+ levels were quantified, indicating a 1.3-fold circadian variance in Ca2+ concentration. Inhibition of ryanodine-receptor-mediated Ca2+ release produced a larger relative decrease in cytosolic Ca2+ at both time points compared to voltage-gated Ca2+channels. These results support the hypothesis that circadian Ca2+ rhythms in SCN neurons are predominantly driven by intracellular Ca2+ channels, although not exclusively so. The study provides a foundation for future experiments to probe Ca2+ signaling in a dynamic biological context using FLAREs.
Collapse
Affiliation(s)
- Amber E. Plante
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Vishnu P. Rao
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Megan A. Rizzo
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Andrea L. Meredith
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| |
Collapse
|
18
|
Association of Circadian Clock Gene Expression with Glioma Tumor Microenvironment and Patient Survival. Cancers (Basel) 2021; 13:cancers13112756. [PMID: 34199348 PMCID: PMC8199552 DOI: 10.3390/cancers13112756] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 05/29/2021] [Indexed: 12/21/2022] Open
Abstract
Simple Summary Gliomas are the most common type of malignant primary brain tumors and are classified according to the cell of origin and genetic features, which can help predict the prognosis and treatment sensitivity. Improving the prognosis remains a challenge; however, chronobiology is a promising field for future works, as circadian clock genes are linked to the tumor biology and outcomes in multiple cancers, including glioma. Here, we examined the relationship of circadian clock genes, IDH mutational status, and prognosis in glioma patients by using unsupervised clustering of the expression of 13 clock genes. We further explored the expression of the clock genes across the tumor regions and cell subpopulations, highlighting the importance of the tumor microenvironment in researching circadian rhythms in cancer. Our research is important for understanding how best to target circadian rhythms to improve patient outcomes in neuro-oncology. Abstract Circadian clock genes have been linked to clinical outcomes in cancer, including gliomas. However, these studies have not accounted for established markers that predict the prognosis, including mutations in Isocitrate Dehydrogenase (IDH), which characterize the majority of lower-grade gliomas and secondary high-grade gliomas. To demonstrate the connection between circadian clock genes and glioma outcomes while accounting for the IDH mutational status, we analyzed multiple publicly available gene expression datasets. The unsupervised clustering of 13 clock gene transcriptomic signatures from The Cancer Genome Atlas showed distinct molecular subtypes representing different disease states and showed the differential prognosis of these groups by a Kaplan–Meier analysis. Further analyses of these groups showed that a low period (PER) gene expression was associated with the negative prognosis and enrichment of the immune signaling pathways. These findings prompted the exploration of the relationship between the microenvironment and clock genes in additional datasets. Circadian clock gene expression was found to be differentially expressed across the anatomical tumor location and cell type. Thus, the circadian clock expression is a potential predictive biomarker in glioma, and further mechanistic studies to elucidate the connections between the circadian clock and microenvironment are warranted.
Collapse
|
19
|
Arellanes-Licea EDC, Pérez-Mendoza M, Carmona-Castro A, Díaz-Muñoz M, Miranda-Anaya M. Obese Neotomodon alstoni mice exhibit sexual dimorphism in the daily profile of circulating melatonin and clock proteins PER1 and BMAL1 in the hypothalamus and peripheral oscillators. Chronobiol Int 2021; 38:584-597. [PMID: 33393371 DOI: 10.1080/07420528.2020.1860999] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 12/02/2020] [Accepted: 12/03/2020] [Indexed: 12/13/2022]
Abstract
Obesity is a global health threat and a risk factor for several metabolic conditions. Though circadian dysfunction has been considered among the multiple causes of obesity, little work has been done to explore the relationship between obesity, circadian dysfunction, and sexual dimorphism. The Neotomodon alstoni mouse is a suitable model for such research. This study employed N. alstoni mice in a chronobiological analysis to determine whether there is circadian desynchronization of relative PER1 and BMAL1 protein levels in the hypothalamus, liver, visceral white adipose tissue, kidney, and heart. It also compared differences between sexes and lean and obese N. alstoni adult mice, by recording behavior and daily circulating serum melatonin as markers of circadian output. We found that obese mice display reduced locomotor activity. Additionally, Cosinor analyses of the relative expression of PER1 and BMAL1 show differences between lean and obese mice in a sex-linked manner. The PER1 24 h rhythm was absent in all tissues of obese males and significant in the tissues of obese females. The BMAL1 24 h rhythm also was significant in most of the tissues tested in lean males, whereas it was significant and shifted the acrophase (peak time of rhythm) in most of the tissues in obese females. Both lean male and female mice showed a rhythmic 24 h pattern of circulating serum melatonin. This daily profile was not only absent in obese mice of both sexes but showed sexual dimorphism. Obese male mice showed lower circulating levels of melatonin compared to lean male mice, but they were higher in obese females compared to lean females. Our results suggest that obesity in N. alstoni is associated with an internal circadian desynchronization in a sex-dependent manner. Overall, this study reinforces the need for further research on the neuroendocrinology of obesity and circadian rhythms using this biological model.
Collapse
Affiliation(s)
- Elvira Del Carmen Arellanes-Licea
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Universidad Nacional Autónoma de México, Querétaro, México
| | - Moisés Pérez-Mendoza
- Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Querétaro, México
| | - Agustín Carmona-Castro
- Departamento de Biología Celular, Facultad de Ciencias, Ciudad Universitaria, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Mauricio Díaz-Muñoz
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México
| | - Manuel Miranda-Anaya
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Universidad Nacional Autónoma de México, Querétaro, México
| |
Collapse
|
20
|
Woller A, Gonze D. Circadian Misalignment and Metabolic Disorders: A Story of Twisted Clocks. BIOLOGY 2021; 10:biology10030207. [PMID: 33801795 PMCID: PMC8001388 DOI: 10.3390/biology10030207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 01/18/2023]
Abstract
Simple Summary In mammals, many physiological processes follow a 24 h rhythmic pattern. These rhythms are governed by a complex network of circadian clocks, which perceives external time cues (notably light and nutrients) and adjusts the timing of metabolic and physiological functions to allow a proper adaptation of the organism to the daily changes in the environmental conditions. Circadian rhythms originate at the cellular level through a transcriptional–translational regulatory network involving a handful of clock genes. In this review, we show how adverse effects caused by ill-timed feeding or jet lag can lead to a dysregulation of this genetic clockwork, which in turn results in altered metabolic regulation and possibly in diseases. We also show how computational modeling can complement experimental observations to understand the design of the clockwork and the onset of metabolic disorders. Abstract Biological clocks are cell-autonomous oscillators that can be entrained by periodic environmental cues. This allows organisms to anticipate predictable daily environmental changes and, thereby, to partition physiological processes into appropriate phases with respect to these changing external conditions. Nowadays our 24/7 society challenges this delicate equilibrium. Indeed, many studies suggest that perturbations such as chronic jet lag, ill-timed eating patterns, or shift work increase the susceptibility to cardiometabolic disorders, diabetes, and cancers. However the underlying mechanisms are still poorly understood. A deeper understanding of this complex, dynamic system requires a global holistic approach for which mathematical modeling can be highly beneficial. In this review, we summarize several experimental works pertaining to the effect of adverse conditions on clock gene expression and on physiology, and we show how computational models can bring interesting insights into the links between circadian misalignment and metabolic diseases.
Collapse
Affiliation(s)
- Aurore Woller
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel;
| | - Didier Gonze
- Unité de Chronobiologie Théorique, Faculté des Sciences CP 231, Université Libre de Bruxelles, Bvd du Triomphe, 1050 Bruxelles, Belgium
- Correspondence:
| |
Collapse
|
21
|
Seasonality and light phase-resetting in the mammalian circadian rhythm. Sci Rep 2020; 10:19506. [PMID: 33177530 PMCID: PMC7658258 DOI: 10.1038/s41598-020-74002-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 09/18/2020] [Indexed: 11/13/2022] Open
Abstract
We study the impact of light on the mammalian circadian system using the theory of phase response curves. Using a recently developed ansatz we derive a low-dimensional macroscopic model for the core circadian clock in mammals. Significantly, the variables and parameters in our model have physiological interpretations and may be compared with experimental results. We focus on the effect of four key factors which help shape the mammalian phase response to light: heterogeneity in the population of oscillators, the structure of the typical light phase response curve, the fraction of oscillators which receive direct light input and changes in the coupling strengths associated with seasonal day-lengths. We find these factors can explain several experimental results and provide insight into the processing of light information in the mammalian circadian system. In particular, we find that the sensitivity of the circadian system to light may be modulated by changes in the relative coupling forces between the light sensing and non-sensing populations. Finally, we show how seasonal day-length, after-effects to light entrainment and seasonal variations in light sensitivity in the mammalian circadian clock are interrelated.
Collapse
|
22
|
Ono D, Mukai Y, Hung CJ, Chowdhury S, Sugiyama T, Yamanaka A. The mammalian circadian pacemaker regulates wakefulness via CRF neurons in the paraventricular nucleus of the hypothalamus. SCIENCE ADVANCES 2020; 6:6/45/eabd0384. [PMID: 33158870 PMCID: PMC7673716 DOI: 10.1126/sciadv.abd0384] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 09/23/2020] [Indexed: 05/29/2023]
Abstract
In mammals, the daily rhythms of physiological functions are timed by the central circadian clock located in the suprachiasmatic nucleus (SCN) of the hypothalamus. Although the importance of the SCN for the regulation of sleep/wakefulness has been suggested, little is known about the neuronal projections from the SCN, which regulate sleep/wakefulness. Here, we show that corticotropin-releasing factor (CRF) neurons in the hypothalamic paraventricular nucleus mediate circadian rhythms in the SCN and regulate wakefulness. Optogenetic activation of CRF neurons promoted wakefulness through orexin/hypocretin neurons in the lateral hypothalamus. In vivo Ca2+ recording showed that CRF neurons were active at the initiation of wakefulness. Furthermore, chemogenetic suppression and ablation of CRF neurons decreased locomotor activity and time in wakefulness. Last, a combination of optical manipulation and Ca2+ imaging revealed that neuronal activity of CRF neurons was negatively regulated by GABAergic neurons in the SCN. Our findings provide notable insights into circadian regulation of sleep/wakefulness in mammals.
Collapse
Affiliation(s)
- Daisuke Ono
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
- CREST, JST, Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Yasutaka Mukai
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
- CREST, JST, Honcho Kawaguchi, Saitama 332-0012, Japan
- JSPS Research Fellowship for Young Scientists, Tokyo 102-0083, Japan
| | - Chi Jung Hung
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
- CREST, JST, Honcho Kawaguchi, Saitama 332-0012, Japan
- JSPS Research Fellowship for Young Scientists, Tokyo 102-0083, Japan
| | - Srikanta Chowdhury
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
- CREST, JST, Honcho Kawaguchi, Saitama 332-0012, Japan
| | | | - Akihiro Yamanaka
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
- CREST, JST, Honcho Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|
23
|
van Soest I, del Olmo M, Schmal C, Herzel H. Nonlinear phenomena in models of the circadian clock. J R Soc Interface 2020; 17:20200556. [PMID: 32993432 PMCID: PMC7536064 DOI: 10.1098/rsif.2020.0556] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 08/27/2020] [Indexed: 12/14/2022] Open
Abstract
The mammalian circadian clock is well-known to be important for our sleep-wake cycles, as well as other daily rhythms such as temperature regulation, hormone release or feeding-fasting cycles. Under normal conditions, these daily cyclic events follow 24 h limit cycle oscillations, but under some circumstances, more complex nonlinear phenomena, such as the emergence of chaos, or the splitting of physiological dynamics into oscillations with two different periods, can be observed. These nonlinear events have been described at the organismic and tissue level, but whether they occur at the cellular level is still unknown. Our results show that period-doubling, chaos and splitting appear in different models of the mammalian circadian clock with interlocked feedback loops and in the absence of external forcing. We find that changes in the degradation of clock genes and proteins greatly alter the dynamics of the system and can induce complex nonlinear events. Our findings highlight the role of degradation rates in determining the oscillatory behaviour of clock components, and can contribute to the understanding of molecular mechanisms of circadian dysregulation.
Collapse
Affiliation(s)
- Inge van Soest
- Institute for Theoretical Biology, Charité and Humboldt Universität zu Berlin, 10115 Berlin, Germany
- Master Program Neuroscience and Cognition, Utrecht University, Utrecht, The Netherlands
| | - Marta del Olmo
- Institute for Theoretical Biology, Charité and Humboldt Universität zu Berlin, 10115 Berlin, Germany
| | - Christoph Schmal
- Institute for Theoretical Biology, Charité and Humboldt Universität zu Berlin, 10115 Berlin, Germany
| | - Hanspeter Herzel
- Institute for Theoretical Biology, Charité and Humboldt Universität zu Berlin, 10115 Berlin, Germany
| |
Collapse
|
24
|
Hartsock MJ, Spencer RL. Memory and the circadian system: Identifying candidate mechanisms by which local clocks in the brain may regulate synaptic plasticity. Neurosci Biobehav Rev 2020; 118:134-162. [PMID: 32712278 DOI: 10.1016/j.neubiorev.2020.07.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 07/14/2020] [Accepted: 07/18/2020] [Indexed: 12/11/2022]
Abstract
The circadian system is an endogenous biological network responsible for coordinating near-24-h cycles in behavior and physiology with daily timing cues from the external environment. In this review, we explore how the circadian system regulates memory formation, retention, and recall. Circadian rhythms in these memory processes may arise through several endogenous pathways, and recent work highlights the importance of genetic timekeepers found locally within tissues, called local clocks. We evaluate the circadian memory literature for evidence of local clock involvement in memory, identifying potential nodes for direct interactions between local clock components and mechanisms of synaptic plasticity. Our discussion illustrates how local clocks may pervasively modulate neuronal plastic capacity, a phenomenon that we designate here as circadian metaplasticity. We suggest that this function of local clocks supports the temporal optimization of memory processes, illuminating the potential for circadian therapeutic strategies in the prevention and treatment of memory impairment.
Collapse
Affiliation(s)
- Matthew J Hartsock
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
| | - Robert L Spencer
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
| |
Collapse
|
25
|
Sun H, Li C, Zhang Y, Jiang M, Dong Q, Wang Z. Light-resetting impact on behavior and the central circadian clock in two vole species (genus: Lasiopodomys). Comp Biochem Physiol B Biochem Mol Biol 2020; 248-249:110478. [PMID: 32687979 DOI: 10.1016/j.cbpb.2020.110478] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/03/2020] [Accepted: 07/13/2020] [Indexed: 10/23/2022]
Abstract
The behavioral circadian rhythms of subterranean rodents show intra- and interspecies diversity in terms of adaptation to dark underground environments, but the endogenous molecular mechanism of rhythm regulation in the suprachiasmatic nuclei (SCN) is stable to many species. In this study, we sought to determine the rhythms of behavior and central molecular regulatory mechanisms in the SCN of the subterranean Mandarin voles (Lasiopodomys mandarinus) compared with a related aboveground species, Brandt's voles (Lasiopodomys brandtii). Both species were reared under a 12 L:12 D cycle or in continuous darkness for 4 weeks. The pattern of wheel-running activity was similar in both species and had a periodicity of almost 24 h regardless of rearing conditions. However, the intensity of daily activity in Brandt's voles decreased markedly in darkness, while there was no significant difference in activity intensity in mandarin voles under different light regimes. In both vole species, all tested genes in the SCN showed significant time-dependent expression regardless of rearing conditions, and the expression levels of most genes did not differ significantly between different species and conditions. However, the peak phase shift in gene expression differed between the two species. In conclusion, behavioral patterns in mandarin and Brandt's voles were regulated by a stable molecular endogenous biological clock. The observed differences in activity intensity and phase shift suggest that different mechanisms regulate circadian rhythms in different living environments.
Collapse
Affiliation(s)
- Hong Sun
- College of Physical Education (main Campus), Zhengzhou University, Zhengzhou, Henan Province, China; School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, China
| | - Chuyi Li
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, China
| | - Yifeng Zhang
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, China
| | - Mengwan Jiang
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, China
| | - Qianqian Dong
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, China
| | - Zhenlong Wang
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, China.
| |
Collapse
|
26
|
Ono D, Honma KI, Honma S. GABAergic mechanisms in the suprachiasmatic nucleus that influence circadian rhythm. J Neurochem 2020; 157:31-41. [PMID: 32198942 DOI: 10.1111/jnc.15012] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/06/2020] [Accepted: 03/09/2020] [Indexed: 01/23/2023]
Abstract
The mammalian central circadian clock is located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN contains multiple circadian oscillators which synchronize with each other via several neurotransmitters. Importantly, an inhibitory neurotransmitter, γ-amino butyric acid (GABA), is expressed in almost all SCN neurons. In this review, we discuss how GABA influences circadian rhythms in the SCN. Excitatory and inhibitory effects of GABA may depend on intracellular Cl- concentration, in which several factors such as day-length, time of day, development, and region in the SCN may be involved. GABA also mediates oscillatory coupling of the circadian rhythms in the SCN. Recent genetic approaches reveal that GABA refines circadian output rhythms, but not circadian oscillations in the SCN. Since several efferent projections of the SCN have been suggested, GABA might work downstream of neuronal pathways from the SCN which regulate the temporal order of physiology and behavior.
Collapse
Affiliation(s)
- Daisuke Ono
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan.,Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Ken-Ichi Honma
- Research and Education Center for Brain Science, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Sato Honma
- Research and Education Center for Brain Science, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| |
Collapse
|
27
|
Ruoff P, Nishiyama N. Frequency switching between oscillatory homeostats and the regulation of p53. PLoS One 2020; 15:e0227786. [PMID: 32433703 PMCID: PMC7239446 DOI: 10.1371/journal.pone.0227786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Accepted: 05/03/2020] [Indexed: 11/19/2022] Open
Abstract
Homeostasis is an essential concept to understand the stability of organisms and their adaptive behaviors when coping with external and internal assaults. Many hormones that take part in homeostatic control come in antagonistic pairs, such as glucagon and insulin reflecting the inflow and outflow compensatory mechanisms to control a certain internal variable, such as blood sugar levels. By including negative feedback loops homeostatic controllers can exhibit oscillations with characteristic frequencies. In this paper we demonstrate the associated frequency changes in homeostatic systems when individual controllers -in a set of interlocked feedback loops- gain control in response to environmental changes. Taking p53 as an example, we show how Per2, ATM and Mdm2 feedback loops -interlocked with p53- gain individual control in dependence to the level of DNA damage, and how each of these controllers provide certain functionalities in their regulation of p53. In unstressed cells, the circadian regulator Per2 ensures a basic p53 level to allow its rapid up-regulation in case of DNA damage. When DNA damage occurs the ATM controller increases the level of p53 and defends it towards uncontrolled degradation, which despite DNA damage, would drive p53 to lower values and p53 dysfunction. Mdm2 on its side keeps p53 at a high but sub-apoptotic level to avoid premature apoptosis. However, with on-going DNA damage the Mdm2 set-point is increased by HSP90 and other p53 stabilizers leading finally to apoptosis. An emergent aspect of p53 upregulation during cell stress is the coordinated inhibition of ubiquitin-independent and ubiquitin-dependent degradation reactions. Whether oscillations serve a function or are merely a by-product of the controllers are discussed in view of the finding that homeostatic control of p53, as indicated above, does in principle not require oscillatory homeostats.
Collapse
Affiliation(s)
- Peter Ruoff
- Department of Chemistry, Bioscience, and Environmental Engineering, University of Stavanger, Stavanger, Norway
- * E-mail:
| | - Nobuaki Nishiyama
- Division of Mathematical and Physical Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Japan
| |
Collapse
|
28
|
Sun H, Cui Z, Zhang Y, Pan D, Wang Z. Expression patterns of clock genes in the hypothalamus and eye of two Lasiopodomys species. Chronobiol Int 2020; 37:327-338. [PMID: 32308052 DOI: 10.1080/07420528.2020.1730881] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
To investigate the relationship between light sensing systems in the eye and circadian oscillators in the hypothalamus of subterranean rodents, we studied subterranean Mandarin voles (Lasiopodomys mandarinus) that spend their entire lives under dark conditions with degenerated eyes, and compared oscillatory expression patterns of clock genes in the hypothalamus and eye between Mandarin voles and their aboveground relatives, Brandt's voles (L. brandtii). Individuals of both vole species were kept under a 12-h light/12-h dark condition or continuous dark condition for 4 weeks. In both species, the expressions of most genes showed significant cosine rhythmicity in the hypothalamus but relatively weak rhythmicity in the eye. The number of rhythmic genes in the eye of Mandarin voles increased under the dark condition, but the opposite trend was observed in the eye of Brandt's voles. The expression levels of most clock genes in the hypothalamus of both vole species did not significantly differ between the two conditions, but unlike in Mandarin voles, these expression levels significantly decreased in the eye of Brandt's voles kept under the dark condition. In both vole species, the peak phase of most clock genes exhibited advanced or invariant change in the hypothalamus under the dark condition, and the peak phase of most clock genes showed consistent changes between the eye and hypothalamus of Mandarin voles. However, most clock genes in the eye showed a delayed phase in Brandt's voles kept under the dark condition. In conclusion, the hypothalamus plays an important role in both vole species irrespective of the light condition. However, the expression patterns of clock genes in the eye differed between the vole species, indicating that each species adapted differently to their environments.
Collapse
Affiliation(s)
- Hong Sun
- School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, Henan Province, P.R. China.,School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, P.R. China
| | - Zhenwei Cui
- School of Physical Education (Main Campus), Zhengzhou University, Zhengzhou, Henan Province, P.R. China.,School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, P.R. China
| | - Yifeng Zhang
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, P.R. China
| | - Dan Pan
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, P.R. China
| | - Zhenlong Wang
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan Province, P.R. China
| |
Collapse
|
29
|
Schmal C, Herzel H, Myung J. Clocks in the Wild: Entrainment to Natural Light. Front Physiol 2020; 11:272. [PMID: 32300307 PMCID: PMC7142224 DOI: 10.3389/fphys.2020.00272] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 03/09/2020] [Indexed: 01/09/2023] Open
Abstract
Entrainment denotes a process of coordinating the internal circadian clock to external rhythmic time-cues (Zeitgeber), mainly light. It is facilitated by stronger Zeitgeber signals and smaller period differences between the internal clock and the external Zeitgeber. The phase of entrainment ψ is a result of this process on the side of the circadian clock. On Earth, the period of the day-night cycle is fixed to 24 h, while the periods of circadian clocks distribute widely due to natural variation within and between species. The strength and duration of light depend locally on season and geographic latitude. Therefore, entrainment characteristics of a circadian clock vary under a local light environment and distribute along geoecological settings. Using conceptual models of circadian clocks, we investigate how local conditions of natural light shape global patterning of entrainment through seasons. This clock-side entrainment paradigm enables us to predict systematic changes in the global distribution of chronotypes.
Collapse
Affiliation(s)
- Christoph Schmal
- Department of Biology, Faculty of Life Sciences, Institute for Theoretical Biology, Humboldt Universität zu Berlin, Berlin, Germany
| | - Hanspeter Herzel
- Department Basic Sciences, Institute for Theoretical Biology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jihwan Myung
- Graduate Institute of Mind, Brain, and Consciousness, Taipei Medical University, Taipei, Taiwan.,Brain and Consciousness Research Centre, Taipei Medical University-Shuang Ho Hospital, Ministry of Health and Welfare, New Taipei City, Taiwan.,Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan.,Computational Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| |
Collapse
|
30
|
Harvey JRM, Plante AE, Meredith AL. Ion Channels Controlling Circadian Rhythms in Suprachiasmatic Nucleus Excitability. Physiol Rev 2020; 100:1415-1454. [PMID: 32163720 DOI: 10.1152/physrev.00027.2019] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Animals synchronize to the environmental day-night cycle by means of an internal circadian clock in the brain. In mammals, this timekeeping mechanism is housed in the suprachiasmatic nucleus (SCN) of the hypothalamus and is entrained by light input from the retina. One output of the SCN is a neural code for circadian time, which arises from the collective activity of neurons within the SCN circuit and comprises two fundamental components: 1) periodic alterations in the spontaneous excitability of individual neurons that result in higher firing rates during the day and lower firing rates at night, and 2) synchronization of these cellular oscillations throughout the SCN. In this review, we summarize current evidence for the identity of ion channels in SCN neurons and the mechanisms by which they set the rhythmic parameters of the time code. During the day, voltage-dependent and independent Na+ and Ca2+ currents, as well as several K+ currents, contribute to increased membrane excitability and therefore higher firing frequency. At night, an increase in different K+ currents, including Ca2+-activated BK currents, contribute to membrane hyperpolarization and decreased firing. Layered on top of these intrinsically regulated changes in membrane excitability, more than a dozen neuromodulators influence action potential activity and rhythmicity in SCN neurons, facilitating both synchronization and plasticity of the neural code.
Collapse
Affiliation(s)
- Jenna R M Harvey
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Amber E Plante
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Andrea L Meredith
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| |
Collapse
|
31
|
Hastings MH, Smyllie NJ, Patton AP. Molecular-genetic Manipulation of the Suprachiasmatic Nucleus Circadian Clock. J Mol Biol 2020; 432:3639-3660. [PMID: 31996314 DOI: 10.1016/j.jmb.2020.01.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/10/2020] [Accepted: 01/15/2020] [Indexed: 01/08/2023]
Abstract
Circadian (approximately daily) rhythms of physiology and behaviour adapt organisms to the alternating environments of day and night. The suprachiasmatic nucleus (SCN) of the hypothalamus is the principal circadian timekeeper of mammals. The mammalian cell-autonomous circadian clock is built around a self-sustaining transcriptional-translational negative feedback loop (TTFL) in which the negative regulators Per and Cry suppress their own expression, which is driven by the positive regulators Clock and Bmal1. Importantly, such TTFL-based clocks are present in all major tissues across the organism, and the SCN is their central co-ordinator. First, we analyse SCN timekeeping at the cell-autonomous and the circuit-based levels of organisation. We consider how molecular-genetic manipulations have been used to probe cell-autonomous timing in the SCN, identifying the integral components of the clock. Second, we consider new approaches that enable real-time monitoring of the activity of these clock components and clock-driven cellular outputs. Finally, we review how intersectional genetic manipulations of the cell-autonomous clockwork can be used to determine how SCN cells interact to generate an ensemble circadian signal. Critically, it is these network-level interactions that confer on the SCN its emergent properties of robustness, light-entrained phase and precision- properties that are essential for its role as the central co-ordinator. Remaining gaps in knowledge include an understanding of how the TTFL proteins behave individually and in complexes: whether particular SCN neuronal populations act as pacemakers, and if so, by which signalling mechanisms, and finally the nature of the recently discovered role of astrocytes within the SCN network.
Collapse
Affiliation(s)
- Michael H Hastings
- Division of Neurobiology, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, CB2 0QH, UK.
| | - Nicola J Smyllie
- Division of Neurobiology, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, CB2 0QH, UK
| | - Andrew P Patton
- Division of Neurobiology, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, CB2 0QH, UK
| |
Collapse
|
32
|
Heyde I, Oster H. Differentiating external zeitgeber impact on peripheral circadian clock resetting. Sci Rep 2019; 9:20114. [PMID: 31882641 PMCID: PMC6934673 DOI: 10.1038/s41598-019-56323-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 12/10/2019] [Indexed: 12/15/2022] Open
Abstract
Circadian clocks regulate physiological functions, including energy metabolism, along the 24-hour day cycle. The mammalian clock system is organized in a hierarchical manner with a coordinating pacemaker residing in the hypothalamic suprachiasmatic nucleus (SCN). The SCN clock is reset primarily by the external light-dark cycle while other zeitgebers such as the timing of food intake are potent synchronizers of many peripheral tissue clocks. Under conflicting zeitgeber conditions, e.g. during shift work, phase synchrony across the clock network is disrupted promoting the development of metabolic disorders. We established a zeitgeber desynchrony (ZD) paradigm to quantify the differential contributions of the two main zeitgebers, light and food, to the resetting of specific tissue clocks and the effect on metabolic homeostasis in mice. Under 28-hour light-dark and 24-hour feeding-fasting conditions SCN and peripheral clock, as well as activity and hormonal rhythms showed specific periodicities aligning in-between those of the two zeitgebers. During ZD, metabolic homeostasis was cyclic with mice gaining weight under synchronous and losing weight under conflicting zeitgeber conditions. In summary, our study establishes an experimental paradigm to compare zeitgeber input in vivo and study the physiological consequences of chronodisruption.
Collapse
Affiliation(s)
- Isabel Heyde
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany
| | - Henrik Oster
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany.
| |
Collapse
|
33
|
Schmal C, Ono D, Myung J, Pett JP, Honma S, Honma KI, Herzel H, Tokuda IT. Weak coupling between intracellular feedback loops explains dissociation of clock gene dynamics. PLoS Comput Biol 2019; 15:e1007330. [PMID: 31513579 PMCID: PMC6759184 DOI: 10.1371/journal.pcbi.1007330] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 09/24/2019] [Accepted: 08/12/2019] [Indexed: 01/11/2023] Open
Abstract
Circadian rhythms are generated by interlocked transcriptional-translational negative feedback loops (TTFLs), the molecular process implemented within a cell. The contributions, weighting and balancing between the multiple feedback loops remain debated. Dissociated, free-running dynamics in the expression of distinct clock genes has been described in recent experimental studies that applied various perturbations such as slice preparations, light pulses, jet-lag, and culture medium exchange. In this paper, we provide evidence that this "presumably transient" dissociation of circadian gene expression oscillations may occur at the single-cell level. Conceptual and detailed mechanistic mathematical modeling suggests that such dissociation is due to a weak interaction between multiple feedback loops present within a single cell. The dissociable loops provide insights into underlying mechanisms and general design principles of the molecular circadian clock.
Collapse
Affiliation(s)
- Christoph Schmal
- Department of Mechanical Engineering, Ritsumeikan University, Kusatsu, Japan
- Institute for Theoretical Biology, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Institute for Theoretical Biology, Humboldt Universität zu Berlin, Berlin, Germany
| | - Daisuke Ono
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Jihwan Myung
- Laboratory of Braintime, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
- Graduate Institute of Mind, Brain, and Consciousness, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan
- TMU Research Center of Brain and Consciousness, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
- Computational Neuroscience Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
| | - J. Patrick Pett
- Institute for Theoretical Biology, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Institute for Theoretical Biology, Humboldt Universität zu Berlin, Berlin, Germany
| | - Sato Honma
- Department of Chronomedicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Ken-Ichi Honma
- Department of Chronomedicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Hanspeter Herzel
- Institute for Theoretical Biology, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Institute for Theoretical Biology, Humboldt Universität zu Berlin, Berlin, Germany
| | - Isao T. Tokuda
- Department of Mechanical Engineering, Ritsumeikan University, Kusatsu, Japan
| |
Collapse
|
34
|
Hannibal J, Norn THB, Georg B, Fahrenkrug J. Spatiotemporal expression pattern of PERIOD 1 and PERIOD 2 in the mouse SCN is dependent on VIP receptor 2 signaling. Eur J Neurosci 2019; 50:3115-3132. [PMID: 31211910 DOI: 10.1111/ejn.14482] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 04/29/2019] [Accepted: 05/21/2019] [Indexed: 11/29/2022]
Abstract
Neurons of the hypothalamic suprachiasmatic nucleus (SCN) express clock genes, which regulate their own transcription and generate daily output signals driving circadian rhythmic behavior and physiology. The neuropeptide VIP and its specific receptor, the VPAC2 receptor, are important for synchronization of clock neurons. In the present study, we characterized PER1 and PER2 expressing neurons in wild-type and VPAC2-deficient mice. We found evidence for distinct spatiotemporal circadian oscillation in the expression of the PER genes in two separate clusters of SCN neurons. In wild-type mice corresponding to the SCN shell and ventral core, high expression of PER was found at lights-off most likely representing an evening clock (E-clock). In another smaller cluster of neurons located in the central core of the SCN, PER expression peaks in antiphase at lights-on and could represent a morning clock (M-clock). BMAL1 immunoreactivity was found to be expressed in antiphase to PER in M and E neurons, respectively. PER was found in 98% of neurons expressing vasopressin (AVP) and in 92% of VIP neurons. The chemotype of M neurons was not identified. M but not E cells were responsive to long but not short photoperiods. The expression of the VPAC2 receptor was found in both M and E cells, and VPAC2-deficient mice displayed markedly blunted PER expression in both cell clusters of the SCN. Conclusion: These observations support the existence of M and E clocks involved in circadian and seasonal adaptation, which seem dependent on intact VIP/VPAC2 signaling in the SCN.
Collapse
Affiliation(s)
- Jens Hannibal
- Department of Clinical Biochemistry, Faculty of Health Sciences, Bispebjerg Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Tania H B Norn
- Department of Clinical Biochemistry, Faculty of Health Sciences, Bispebjerg Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Birgitte Georg
- Department of Clinical Biochemistry, Faculty of Health Sciences, Bispebjerg Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Jan Fahrenkrug
- Department of Clinical Biochemistry, Faculty of Health Sciences, Bispebjerg Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
35
|
Nicholls SK, Casiraghi LP, Wang W, Weber ET, Harrington ME. Evidence for Internal Desynchrony Caused by Circadian Clock Resetting. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:259-270. [PMID: 31249487 PMCID: PMC6585527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Circadian disruption has been linked to markers for poor health outcomes in humans and animal models. What is it about circadian disruption that is problematic? One hypothesis is that phase resetting of the circadian system, which occurs in response to changes in environmental timing cues, leads to internal desynchrony within the organism. Internal desynchrony is understood as acute changes in phase relationships between biological rhythms from different cell groups, tissues, or organs within the body. Do we have strong evidence for internal desynchrony associated with or caused by circadian clock resetting? Here we review the literature, highlighting several key studies from measures of gene expression in laboratory rodents. We conclude that current evidence offers strong support for the premise that some protocols for light-induced resetting are associated with internal desynchrony. It is important to continue research to test whether internal desynchrony is necessary and/or sufficient for negative health impact of circadian disruption.
Collapse
Affiliation(s)
| | | | - Wanqi Wang
- Department of Genetics and Development, Columbia University Medical Center, New York, NY
| | - E. Todd Weber
- Department of Biology, Behavioral Neuroscience and Health Sciences, Rider University, Lawrenceville, NJ
| | - Mary E. Harrington
- Neuroscience Program, Smith College, Northampton, MA,To whom all correspondence should be addressed: Mary Harrington, Neuroscience Program, Clark Science Center, 44 College Lane, Smith College, Northampton, MA 01060; Tel: (413) 585-3925; Fax: (413) 585-3786;
| |
Collapse
|
36
|
Ono D, Honma KI, Yanagawa Y, Yamanaka A, Honma S. GABA in the suprachiasmatic nucleus refines circadian output rhythms in mice. Commun Biol 2019; 2:232. [PMID: 31263776 PMCID: PMC6588595 DOI: 10.1038/s42003-019-0483-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 05/29/2019] [Indexed: 01/10/2023] Open
Abstract
In mammals, the circadian rhythms are regulated by the central clock located in the hypothalamic suprachiasmatic nucleus (SCN), which is composed of heterogeneous neurons with various neurotransmitters. Among them an inhibitory neurotransmitter, γ-Amino-Butyric-Acid (GABA), is expressed in almost all SCN neurons, however, its role in the circadian physiology is still unclear. Here, we show that the SCN of fetal mice lacking vesicular GABA transporter (VGAT-/-) or GABA synthesizing enzyme, glutamate decarboxylase (GAD65-/-/67-/-), shows burst firings associated with large Ca2+ spikes throughout 24 hours, which spread over the entire SCN slice in synchrony. By contrast, circadian PER2 rhythms in VGAT-/- and GAD65-/-/67-/- SCN remain intact. SCN-specific VGAT deletion in adult mice dampens circadian behavior rhythm. These findings indicate that GABA in the fetal SCN is necessary for refinement of the circadian firing rhythm and, possibly, for stabilizing the output signals, but not for circadian integration of multiple cellular oscillations.
Collapse
Affiliation(s)
- Daisuke Ono
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601 Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya, 466-8550 Japan
| | - Ken-ichi Honma
- Research and Education Center for Brain Science, Hokkaido University Graduate School of Medicine, Sapporo, 060-8638 Japan
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511 Japan
| | - Akihiro Yamanaka
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601 Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya, 466-8550 Japan
| | - Sato Honma
- Research and Education Center for Brain Science, Hokkaido University Graduate School of Medicine, Sapporo, 060-8638 Japan
| |
Collapse
|
37
|
Doi M, Shimatani H, Atobe Y, Murai I, Hayashi H, Takahashi Y, Fustin JM, Yamaguchi Y, Kiyonari H, Koike N, Yagita K, Lee C, Abe M, Sakimura K, Okamura H. Non-coding cis-element of Period2 is essential for maintaining organismal circadian behaviour and body temperature rhythmicity. Nat Commun 2019; 10:2563. [PMID: 31189882 PMCID: PMC6561950 DOI: 10.1038/s41467-019-10532-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 05/16/2019] [Indexed: 12/22/2022] Open
Abstract
Non-coding cis-regulatory elements are essential determinants of development, but their exact impacts on behavior and physiology in adults remain elusive. Cis-element-based transcriptional regulation is believed to be crucial for generating circadian rhythms in behavior and physiology. However, genetic evidence supporting this model is based on mutations in the protein-coding sequences of clock genes. Here, we report generation of mutant mice carrying a mutation only at the E'-box cis-element in the promoter region of the core clock gene Per2. The Per2 E'-box mutation abolishes sustainable molecular clock oscillations and renders circadian locomotor activity and body temperature rhythms unstable. Without the E'-box, Per2 messenger RNA and protein expression remain at mid-to-high levels. Our work delineates the Per2 E'-box as a critical nodal element for keeping sustainable cell-autonomous circadian oscillation and reveals the extent of the impact of the non-coding cis-element in daily maintenance of animal locomotor activity and body temperature rhythmicity.
Collapse
Affiliation(s)
- Masao Doi
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan.
| | - Hiroyuki Shimatani
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Yuta Atobe
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Iori Murai
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan.,Laboratory of Molecular Brain Science, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Hida Hayashi
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Yukari Takahashi
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Jean-Michel Fustin
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Yoshiaki Yamaguchi
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan
| | - Hiroshi Kiyonari
- Laboratories for Animal Resource Development and Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan
| | - Nobuya Koike
- Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Kazuhiro Yagita
- Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Choogon Lee
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
| | - Manabu Abe
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, 951-8585, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, 951-8585, Japan
| | - Hitoshi Okamura
- Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan. .,Laboratory of Molecular Brain Science, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Kyoto, 606-8501, Japan.
| |
Collapse
|
38
|
Haque SN, Booreddy SR, Welsh DK. Effects of BMAL1 Manipulation on the Brain's Master Circadian Clock and Behavior. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:251-258. [PMID: 31249486 PMCID: PMC6585533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Bmal1 is the only single circadian clock gene that is essential for rhythmic gene expression in the mammalian circadian timing system. Genetic approaches targeting Bmal1 expression have been used to further assess its role in the circadian clock and to test for behavioral effects of clock disruption. In particular, disruptions in circadian clock function have been implicated in human mood disorders, and clock gene manipulation in mice may provide valuable models for studying depression-like behavior. In this review, we explore various approaches to manipulating Bmal1 in mouse models and review their effects on the brain's master circadian pacemaker, on circadian rhythmicity in other brain regions, and on circadian and mood-related behavior.
Collapse
Affiliation(s)
- Samreen N. Haque
- Department of Psychiatry and Center for Circadian Biology, University of California, San Diego, La Jolla, CA
| | - Sathwik R. Booreddy
- Department of Psychiatry and Center for Circadian Biology, University of California, San Diego, La Jolla, CA
| | - David K. Welsh
- Department of Psychiatry and Center for Circadian Biology, University of California, San Diego, La Jolla, CA
- Psychiatry Service, VA San Diego Healthcare, San Diego, CA
| |
Collapse
|
39
|
El Cheikh Hussein L, Mollard P, Bonnefont X. Molecular and Cellular Networks in The Suprachiasmatic Nuclei. Int J Mol Sci 2019; 20:ijms20082052. [PMID: 31027315 PMCID: PMC6514755 DOI: 10.3390/ijms20082052] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 04/18/2019] [Accepted: 04/23/2019] [Indexed: 12/20/2022] Open
Abstract
Why do we experience the ailments of jetlag when we travel across time zones? Why is working night-shifts so detrimental to our health? In other words, why can’t we readily choose and stick to non-24 h rhythms? Actually, our daily behavior and physiology do not simply result from the passive reaction of our organism to the external cycle of days and nights. Instead, an internal clock drives the variations in our bodily functions with a period close to 24 h, which is supposed to enhance fitness to regular and predictable changes of our natural environment. This so-called circadian clock relies on a molecular mechanism that generates rhythmicity in virtually all of our cells. However, the robustness of the circadian clock and its resilience to phase shifts emerge from the interaction between cell-autonomous oscillators within the suprachiasmatic nuclei (SCN) of the hypothalamus. Thus, managing jetlag and other circadian disorders will undoubtedly require extensive knowledge of the functional organization of SCN cell networks. Here, we review the molecular and cellular principles of circadian timekeeping, and their integration in the multi-cellular complexity of the SCN. We propose that new, in vivo imaging techniques now enable to address these questions directly in freely moving animals.
Collapse
Affiliation(s)
- Lama El Cheikh Hussein
- Institut de Génomique Fonctionnelle (IGF), University Montpellier, CNRS, INSERM, 34094 Montpellier, France.
| | - Patrice Mollard
- Institut de Génomique Fonctionnelle (IGF), University Montpellier, CNRS, INSERM, 34094 Montpellier, France.
| | - Xavier Bonnefont
- Institut de Génomique Fonctionnelle (IGF), University Montpellier, CNRS, INSERM, 34094 Montpellier, France.
| |
Collapse
|
40
|
Paul JR, Davis JA, Goode LK, Becker BK, Fusilier A, Meador-Woodruff A, Gamble KL. Circadian regulation of membrane physiology in neural oscillators throughout the brain. Eur J Neurosci 2019; 51:109-138. [PMID: 30633846 DOI: 10.1111/ejn.14343] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 12/19/2018] [Accepted: 12/21/2018] [Indexed: 12/21/2022]
Abstract
Twenty-four-hour rhythmicity in physiology and behavior are driven by changes in neurophysiological activity that vary across the light-dark and rest-activity cycle. Although this neural code is most prominent in neurons of the primary circadian pacemaker in the suprachiasmatic nucleus (SCN) of the hypothalamus, there are many other regions in the brain where region-specific function and behavioral rhythmicity may be encoded by changes in electrical properties of those neurons. In this review, we explore the existing evidence for molecular clocks and/or neurophysiological rhythms (i.e., 24 hr) in brain regions outside the SCN. In addition, we highlight the brain regions that are ripe for future investigation into the critical role of circadian rhythmicity for local oscillators. For example, the cerebellum expresses rhythmicity in over 2,000 gene transcripts, and yet we know very little about how circadian regulation drives 24-hr changes in the neural coding responsible for motor coordination. Finally, we conclude with a discussion of how our understanding of circadian regulation of electrical properties may yield insight into disease mechanisms which may lead to novel chronotherapeutic strategies in the future.
Collapse
Affiliation(s)
- Jodi R Paul
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jennifer A Davis
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Lacy K Goode
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Bryan K Becker
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Allison Fusilier
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Aidan Meador-Woodruff
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Karen L Gamble
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| |
Collapse
|
41
|
Lin HH, Qraitem M, Lian Y, Taylor SR, Farkas ME. Analyses of BMAL1 and PER2 Oscillations in a Model of Breast Cancer Progression Reveal Changes With Malignancy. Integr Cancer Ther 2019; 18:1534735419836494. [PMID: 30943793 PMCID: PMC6449806 DOI: 10.1177/1534735419836494] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 02/12/2019] [Accepted: 02/18/2019] [Indexed: 02/06/2023] Open
Abstract
From an epidemiological standpoint, disruptions to circadian rhythms have been shown to contribute to the development of various disease pathologies, including breast cancer. However, it is unclear how altered circadian rhythms are related to malignant transformations at the molecular level. In this article, a series of isogenic breast cancer cells representing disease progression was used to investigate the expression patterns of core circadian clock proteins BMAL1 and PER2. Our model is indicative of 4 stages of breast cancer and includes the following cells: MCF10A (non-malignant), MCF10AT.Cl2 (pre-malignant), MCF10Ca1h (well-differentiated, malignant), and MCF10Ca1a (poorly differentiated, malignant). While studies of circadian rhythms in cancer typically use low-resolution reverse transcription polymerase chain reaction assays, we also employed luciferase reporters BMAL1:Luc and PER2:Luc in real-time luminometry experiments. We found that across all 4 cancer stages, PER2 showed relatively stable oscillations compared with BMAL1. Period estimation using both wavelet-based and damped-sine-fitting methods showed that the periods are distributed over a wide circadian range and there is no clear progression in mean period as cancer severity progresses. Additionally, we used the K-nearest neighbors algorithm to classify the recordings according to cancer line, and found that cancer stages were largely differentiated from one another. Taken together, our data support that there are circadian discrepancies between normal and malignant cells, but it is difficult and insufficient to singularly use period evaluations to differentiate them. Future studies should employ other progressive disease models to determine whether these findings are representative across cancer types or are specific to this series.
Collapse
Affiliation(s)
| | | | - Yue Lian
- Colby College, Waterville, ME, USA
| | | | | |
Collapse
|
42
|
Carmona-Alcocer V, Rohr KE, Joye DAM, Evans JA. Circuit development in the master clock network of mammals. Eur J Neurosci 2018; 51:82-108. [PMID: 30402923 DOI: 10.1111/ejn.14259] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 10/08/2018] [Accepted: 10/31/2018] [Indexed: 12/24/2022]
Abstract
Daily rhythms are generated by the circadian timekeeping system, which is orchestrated by the master circadian clock in the suprachiasmatic nucleus (SCN) of mammals. Circadian timekeeping is endogenous and does not require exposure to external cues during development. Nevertheless, the circadian system is not fully formed at birth in many mammalian species and it is important to understand how SCN development can affect the function of the circadian system in adulthood. The purpose of the current review is to discuss the ontogeny of cellular and circuit function in the SCN, with a focus on work performed in model rodent species (i.e., mouse, rat, and hamster). Particular emphasis is placed on the spatial and temporal patterns of SCN development that may contribute to the function of the master clock during adulthood. Additional work aimed at decoding the mechanisms that guide circadian development is expected to provide a solid foundation upon which to better understand the sources and factors contributing to aberrant maturation of clock function.
Collapse
Affiliation(s)
| | - Kayla E Rohr
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | - Deborah A M Joye
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | - Jennifer A Evans
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| |
Collapse
|
43
|
Saha S, Manisana Singh K, Gupta BBP. Season-dependent differential effect of temperature on diurnal rhythm of expression of core clock genes in the pineal organ of an air-breathing catfish, Clarias gariepinus. BIOL RHYTHM RES 2018. [DOI: 10.1080/09291016.2018.1525139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Saurav Saha
- Environmental Endocrinology Laboratory Department of Zoology, North-Eastern Hill University, Shillong, India
| | - Kshetrimayum Manisana Singh
- Environmental Endocrinology Laboratory Department of Zoology, North-Eastern Hill University, Shillong, India
| | - Braj Bansh Prasad Gupta
- Environmental Endocrinology Laboratory Department of Zoology, North-Eastern Hill University, Shillong, India
| |
Collapse
|
44
|
Nishide S, Honma S, Honma KI. Two coupled circadian oscillations regulate Bmal1-ELuc and Per2-SLR2 expression in the mouse suprachiasmatic nucleus. Sci Rep 2018; 8:14765. [PMID: 30283092 PMCID: PMC6170461 DOI: 10.1038/s41598-018-32516-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 08/01/2018] [Indexed: 11/08/2022] Open
Abstract
Circadian rhythms in clock genes, Bmal1 and Per2 expression were monitored simultaneously in the cultured slice of mouse suprachiasmatic nucleus (SCN) by dual bioluminescent reporters. In the neonatal SCN, the phase-relation between the Bmal1 and Per2 rhythms were significantly changed during culture. Medium exchange produced phase-dependent phase shifts (PRCm) in the Bmal1 rhythms, but not in the Per2 rhythms. As a result, the two circadian rhythms were temporally dissociated after medium exchange. In the adult SCN, the phase-relation between the two rhythms was kept constant during culture at least up to 20 cycles. The amplitude of PRCm in the adult SCN was significantly attenuated in the Bmal1 rhythm, whereas a PRCm was developed in the Per2 rhythm. The circadian period was not systematically affected by medium exchange in either of rhythms, regardless of whether it was in the neonatal or the adult SCN. Tetrodotoxin, a sodium channel blocker, enhanced the phase-response in both rhythms but abolished the phase-dependency. In addition, tetrodotoxin lengthened the circadian period independent of the phase of administration. Thus, the Bmal1 and Per2 rhythms in the SCN are dissociable and likely regulated by distinct circadian oscillators. Bmal1 is the component of a Bmal1/REV-ERBa/ROR loop and Per2 a Per/Cry/BMAL1/CLOCK loop. Both loops could be molecular mechanisms of the two circadian oscillators that are coupled through the protein product of Bmal1. The coupling strength between the two oscillations depends on developmental stages.
Collapse
Affiliation(s)
- Shinya Nishide
- Department of Physiology, Faculty of Medicine, Hokkaido University, Hokkaido, Japan
- Department of Occupational Therapy, School of Rehabilitation Science, Health Science University of Hokkaido, Hokkaido, Japan
| | - Sato Honma
- Research and Education Center for Brain Science, Hokkaido University, Hokkaido, Japan
| | - Ken-Ichi Honma
- Study Group for Monitoring of Brain Functions, Hokkaido University Graduate School of Medicine, Hokkaido, Japan.
| |
Collapse
|
45
|
Noguchi T, Harrison EM, Sun J, May D, Ng A, Welsh DK, Gorman MR. Circadian rhythm bifurcation induces flexible phase resetting by reducing circadian amplitude. Eur J Neurosci 2018; 51:2329-2342. [PMID: 30044021 DOI: 10.1111/ejn.14086] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 06/21/2018] [Accepted: 07/04/2018] [Indexed: 11/29/2022]
Abstract
Shift-work and jet-lag-related disorders are caused by the limited flexibility of the suprachiasmatic nucleus (SCN), a master circadian clock in the hypothalamus, to adjust to new light-dark (LD) cycles. Recent findings confirmed here establish that behavioral jet lag after simulated time-zone travel is virtually eliminated following bifurcated circadian entrainment under a novel and atypical 24-h light:dark:light:dark (LDLD) cycle. To investigate the mechanisms of this fast resetting, we examined the oscillatory stability of the SCN and peripheral tissues in LDLD-bifurcated mice employing the dissection procedure as a perturbing resetting stimulus. SCN, lung, liver, and adrenal tissue were extracted at times throughout the day from female and male PER2::Luciferase knock-in mice entrained to either LDLD or a normal LD cycle. Except for adrenals, the phase of the cultured explants was more strongly set by dissection under LDLD than under normal LD. Acute bioluminescence levels of SCN explants indicate that the rhythm amplitude of PER2 is reduced and phase is altered in LDLD. Real-time quantitative PCR suggests that amplitude and rhythmicity of canonical clock genes in the lung, liver, and kidney are also significantly reduced in LDLD in vivo. Furthermore, spatiotemporal patterns of PER2 peak time in cultured SCN were altered in LDLD. These results suggest that altered gene expression patterns in the SCN caused by bifurcation likely result in fast resetting of behavior and cultured explants, consistent with previously reported mathematical models. Thus, non-invasive, simple light manipulations can make circadian rhythms more adaptable to abrupt shifts in the environmental LD cycle.
Collapse
Affiliation(s)
- Takako Noguchi
- Center for Circadian Biology, UCSD, La Jolla, California
| | - Elizabeth M Harrison
- Center for Circadian Biology, UCSD, La Jolla, California.,Department of Psychology, UCSD, La Jolla, California
| | - Jonathan Sun
- Center for Circadian Biology, UCSD, La Jolla, California.,Department of Psychology, UCSD, La Jolla, California
| | - Deborah May
- Center for Circadian Biology, UCSD, La Jolla, California.,Department of Psychology, UCSD, La Jolla, California
| | - Alan Ng
- Center for Circadian Biology, UCSD, La Jolla, California.,Department of Biology, UCSD, La Jolla, California
| | - David K Welsh
- Center for Circadian Biology, UCSD, La Jolla, California.,Department of Psychiatry, UCSD, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Michael R Gorman
- Center for Circadian Biology, UCSD, La Jolla, California.,Department of Psychology, UCSD, La Jolla, California
| |
Collapse
|
46
|
Mei L, Zhan C, Zhang EE. In Vivo Monitoring of Circadian Clock Gene Expression in the Mouse Suprachiasmatic Nucleus Using Fluorescence Reporters. J Vis Exp 2018. [PMID: 30035762 DOI: 10.3791/56765] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
This technique combines optical fiber mediated fluorescence recordings with the precise delivery of recombinant adeno-associated virus based gene reporters. This new and easy to use in vivo fluorescence monitoring system was developed to record the transcriptional rhythm of the clock gene, Cry1, in the suprachiasmatic nucleus (SCN) of freely moving mice. To do so, a Cry1 transcription fluorescence reporter was designed and packaged into Adeno-associated virus. Purified, concentrated virus was injected into the mouse SCN followed by the insertion of an optic fiber, which was then fixed onto the surface of the brain. The animals were returned to their home cages and allowed a 1-month post-operative recovery period to ensure sufficient reporter expression. Fluorescence was then recorded in freely moving mice via an in vivo monitoring system that was constructed at our institution. For the in vivo recording system, a 488 nm laser was coupled with a 1 × 4 beam-splitter that divided the light into four laser excitation outputs of equal power. This setup enabled us to record from four animals simultaneously. Each of the emitted fluorescence signals was collected via a photomultiplier tube and a data acquisition card. In contrast to the previous bioluminescence in vivo circadian clock recording technique, this fluorescence in vivo recording system allowed the recording of circadian clock gene expression during the light cycle.
Collapse
Affiliation(s)
- Long Mei
- PTN Joint Graduate Program, School of Life Sciences, Peking University; National Institute of Biological Sciences, Beijing
| | - Cheng Zhan
- National Institute of Biological Sciences, Beijing
| | | |
Collapse
|
47
|
Ono D, Honma KI, Yanagawa Y, Yamanaka A, Honma S. Role of GABA in the regulation of the central circadian clock of the suprachiasmatic nucleus. J Physiol Sci 2018; 68:333-343. [PMID: 29560549 PMCID: PMC10717195 DOI: 10.1007/s12576-018-0604-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 03/14/2018] [Indexed: 11/25/2022]
Abstract
In mammals, circadian rhythms, such as sleep/wake cycles, are regulated by the central circadian clock located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN consists of thousands of individual neurons, which exhibit circadian rhythms. They synchronize with each other and produce robust and stable oscillations. Although several neurotransmitters are expressed in the SCN, almost all SCN neurons are γ-amino butyric acid (GABA)-ergic. Several studies have attempted to understand the roles of GABA in the SCN; however, precise mechanisms of the action of GABA in the SCN are still unclear. GABA exhibits excitatory and/or inhibitory characteristics depending on the circadian phase or region in the SCN. It can both synchronize and destabilize cellular circadian rhythms in individual SCN cells. Differing environmental light conditions, such as a long photoperiod, result in the decoupling of circadian oscillators of the dorsal and ventral SCN. This is due to high intracellular chloride concentrations in the dorsal SCN. Because mice with functional GABA deficiency, such as vesicular GABA transporter- and glutamate decarboxylase-deficient mice, are neonatal lethal, research has been limited to pharmacological approaches. Furthermore, different recording methods have been used to understand the roles of GABA in the SCN. The excitability of GABAergic neurons also changes during the postnatal period. Although there are technical difficulties in understanding the functions of GABA in the SCN, technical developments may help uncover new roles of GABA in circadian physiology and behavior.
Collapse
Affiliation(s)
- Daisuke Ono
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
| | - Ken-Ichi Honma
- Research and Education Center for Brain Science, Hokkaido University Graduate School of Medicine, Sapporo, 060-8638, Japan
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, Maebashi, 371-8511, Japan
| | - Akihiro Yamanaka
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Sato Honma
- Research and Education Center for Brain Science, Hokkaido University Graduate School of Medicine, Sapporo, 060-8638, Japan
| |
Collapse
|
48
|
Pett JP, Kondoff M, Bordyugov G, Kramer A, Herzel H. Co-existing feedback loops generate tissue-specific circadian rhythms. Life Sci Alliance 2018; 1:e201800078. [PMID: 30456356 PMCID: PMC6238625 DOI: 10.26508/lsa.201800078] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 06/01/2018] [Accepted: 06/04/2018] [Indexed: 12/04/2022] Open
Abstract
The analysis of tissue-specific data-based models of the gene regulatory network of the mammalian circadian clock reveals organ-specific synergies of feedback loops. Gene regulatory feedback loops generate autonomous circadian rhythms in mammalian tissues. The well-studied core clock network contains many negative and positive regulations. Multiple feedback loops have been discussed as primary rhythm generators but the design principles of the core clock and differences between tissues are still under debate. Here we use global optimization techniques to fit mathematical models to circadian gene expression profiles for different mammalian tissues. It turns out that for every investigated tissue multiple model parameter sets reproduce the experimental data. We extract for all model versions the most essential feedback loops and find auto-inhibitions of period and cryptochrome genes, Bmal1–Rev-erb-α loops, and repressilator motifs as possible rhythm generators. Interestingly, the essential feedback loops differ between tissues, pointing to specific design principles within the hierarchy of mammalian tissue clocks. Self-inhibitions of Per and Cry genes are characteristic for models of suprachiasmatic nucleus clocks, whereas in liver models many loops act in synergy and are connected by a repressilator motif. Tissue-specific use of a network of co-existing synergistic feedback loops could account for functional differences between organs.
Collapse
Affiliation(s)
- J Patrick Pett
- Institute for Theoretical Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Matthew Kondoff
- Institute for Theoretical Biology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Grigory Bordyugov
- Institute for Theoretical Biology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Achim Kramer
- Laboratory of Chronobiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Hanspeter Herzel
- Institute for Theoretical Biology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
49
|
Olejníková L, Polidarová L, Sumová A. Stress affects expression of the clock gene Bmal1 in the suprachiasmatic nucleus of neonatal rats via glucocorticoid-dependent mechanism. Acta Physiol (Oxf) 2018; 223:e13020. [PMID: 29266826 DOI: 10.1111/apha.13020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/13/2017] [Accepted: 12/08/2017] [Indexed: 11/27/2022]
Abstract
AIM The reactivity of the circadian clock in the suprachiasmatic nuclei (SCN) to stressful stimuli has been controversial but most studies have confirmed the resilience of the SCN to stress. We tested the hypothesis that during a critical period shortly after birth, the developing SCN clock is affected by glucocorticoids. METHODS Mothers of 2 rat strains with different sensitivities to stress, that is Wistar rats and spontaneously hypertensive rats (SHR), and their pups were exposed to stressful stimuli every day from delivery, and clock gene expression profiles were detected in the 4-day-old pups' SCN. Levels of glucocorticoids in plasma were measured by LC-MS/MS. The glucocorticoid receptors antagonist mifepristone was administered to pups to block the effect of the glucocorticoids. RESULTS The glucocorticoid receptors were detected at the mRNA and protein levels in the SCN of 4-day-old pups. The exposure of mothers to stressful stimuli elevated their plasma glucocorticoid levels. In Wistar rat pups, combination of daily maternal stress with their manipulation increased the plasma glucocorticoid levels and shifted the Bmal1 rhythm in the SCN which was completely blocked by mifepristone. In contrast, in SHR pups, maternal stress on its own caused phase shift of the Bmal1 expression rhythm in the SCN but the effect was mediated via glucocorticoid-independent mechanism. The Per1 and Per2 expression profiles remained phase-locked to the light/dark cycle. CONCLUSION The results demonstrate that the SCN is sensitive to stressful stimuli early after birth in pups maintained under light/dark conditions and the effect is mediated via glucocorticoid-dependent pathways.
Collapse
Affiliation(s)
- L. Olejníková
- Department of Neurohumoral Regulations; Institute of Physiology of the Czech Academy of Sciences; Prague Czech Republic
- 2 Faculty of Medicine; Charles University; Prague Czech Republic
| | - L. Polidarová
- Department of Neurohumoral Regulations; Institute of Physiology of the Czech Academy of Sciences; Prague Czech Republic
| | - A. Sumová
- Department of Neurohumoral Regulations; Institute of Physiology of the Czech Academy of Sciences; Prague Czech Republic
| |
Collapse
|
50
|
Long-term in vivo recording of circadian rhythms in brains of freely moving mice. Proc Natl Acad Sci U S A 2018; 115:4276-4281. [PMID: 29610316 DOI: 10.1073/pnas.1717735115] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Endogenous circadian clocks control 24-h physiological and behavioral rhythms in mammals. Here, we report a real-time in vivo fluorescence recording system that enables long-term monitoring of circadian rhythms in the brains of freely moving mice. With a designed reporter of circadian clock gene expression, we tracked robust Cry1 transcription reporter rhythms in the suprachiasmatic nucleus (SCN) of WT, Cry1-/- , and Cry2-/- mice in LD (12 h light, 12 h dark) and DD (constant darkness) conditions and verified that signals remained stable for over 6 mo. Further, we recorded Cry1 transcriptional rhythms in the subparaventricular zone (SPZ) and hippocampal CA1/2 regions of WT mice housed under LD and DD conditions. By using a Cre-loxP system, we recorded Per2 and Cry1 transcription rhythms specifically in vasoactive intestinal peptide (VIP) neurons of the SCN. Finally, we demonstrated the dynamics of Per2 and Cry1 transcriptional rhythms in SCN VIP neurons following an 8-h phase advance in the light/dark cycle.
Collapse
|