1
|
McManus D, Patton AP, Smyllie NJ, Chin JW, Hastings MH. PERfect Day: reversible and dose-dependent control of circadian time-keeping in the mouse suprachiasmatic nucleus by translational switching of PERIOD2 protein expression. Eur J Neurosci 2024; 60:5537-5552. [PMID: 39300693 DOI: 10.1111/ejn.16537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 08/06/2024] [Accepted: 08/29/2024] [Indexed: 09/22/2024]
Abstract
The biological clock of the suprachiasmatic nucleus (SCN) orchestrates circadian (approximately daily) rhythms of behaviour and physiology that underpin health. SCN cell-autonomous time-keeping revolves around a transcriptional/translational feedback loop (TTFL) within which PERIOD (PER1,2) and CRYPTOCHROME (CRY1,2) proteins heterodimerise and suppress trans-activation of their encoding genes (Per1,2; Cry1,2). To explore its contribution to SCN time-keeping, we used adeno-associated virus-mediated translational switching to express PER2 (tsPER2) in organotypic SCN slices carrying bioluminescent TTFL circadian reporters. Translational switching requires provision of the non-canonical amino acid, alkyne lysine (AlkK), for protein expression. Correspondingly, AlkK, but not vehicle, induced constitutive expression of tsPER2 in SCN neurons and reversibly and dose-dependently suppressed pPer1-driven transcription in PER-deficient (Per1,2-null) SCN, illustrating the potency of PER2 in negative regulation within the TTFL. Constitutive expression of tsPER2, however, failed to initiate circadian oscillations in arrhythmic PER-deficient SCN. In rhythmic, PER-competent SCN, AlkK dose-dependently reduced the amplitude of PER2-reported oscillations as inhibition by tsPER2 progressively damped the TTFL. tsPER2 also dose-dependently lengthened the period of the SCN TTFL and neuronal calcium rhythms. Following wash-out of AlkK to remove tsPER2, the SCN regained TTFL amplitude and period. Furthermore, SCN retained their pre-washout phase: the removal of tsPER2 did not phase-shift the TTFL. Given that constitutive tsCRY1 can regulate TTFL amplitude and period, but also reset TTFL phase and initiate rhythms in CRY-deficient SCN, these results reveal overlapping and distinct properties of PER2 and CRY1 within the SCN, and emphasise the utility of translational switching to explore the functions of circadian proteins.
Collapse
Affiliation(s)
- David McManus
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Andrew P Patton
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Nicola J Smyllie
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Michael H Hastings
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| |
Collapse
|
2
|
Myung J. Enhancing Bioluminescence Imaging of Cultured Tissue Explants Using Optical Telecompression. SENSORS (BASEL, SWITZERLAND) 2024; 24:6041. [PMID: 39338785 PMCID: PMC11436007 DOI: 10.3390/s24186041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2024] [Revised: 09/17/2024] [Accepted: 09/18/2024] [Indexed: 09/30/2024]
Abstract
Long-term observation of single-cell oscillations within tissue networks is now possible by combining bioluminescence reporters with stable tissue explant culture techniques. This method is particularly effective in revealing the network dynamics in systems with slow oscillations, such as circadian clocks. However, the low intensity of luciferase-based bioluminescence requires signal amplification using specialized cameras (e.g., I-CCDs and EM-CCDs) and prolonged exposure times, increasing baseline noise and reducing temporal resolution. To address this limitation, we implemented a cost-effective optical enhancement technique called telecompression, first used in astrophotography and now commonly used in digital photography. By combining a high numerical aperture objective lens with a magnification-reducing relay lens, we significantly increased the collection efficiency of the bioluminescence signal without raising the baseline CCD noise. This method allows for shorter exposure times in time-lapse imaging, enhancing temporal resolution and enabling more precise period estimations. Our implementation demonstrates the feasibility of telecompression for enhancing bioluminescence imaging for the tissue-level network observation of circadian clocks.
Collapse
Affiliation(s)
- Jihwan Myung
- Braintime Laboratory, Graduate Institute of Mind, Brain and Consciousness (GIMBC), Taipei Medical University, New Taipei City 235, Taiwan;
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan
| |
Collapse
|
3
|
Evans JA, Schwartz WJ. On the origin and evolution of the dual oscillator model underlying the photoperiodic clockwork in the suprachiasmatic nucleus. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024; 210:503-511. [PMID: 37481773 PMCID: PMC10924288 DOI: 10.1007/s00359-023-01659-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 07/07/2023] [Accepted: 07/13/2023] [Indexed: 07/25/2023]
Abstract
Decades have now passed since Colin Pittendrigh first proposed a model of a circadian clock composed of two coupled oscillators, individually responsive to the rising and setting sun, as a flexible solution to the challenge of behavioral and physiological adaptation to the changing seasons. The elegance and predictive power of this postulation has stimulated laboratories around the world in searches to identify and localize such hypothesized evening and morning oscillators, or sets of oscillators, in insects, rodents, and humans, with experimental designs and approaches keeping pace over the years with technological advances in biology and neuroscience. Here, we recount the conceptual origin and highlight the subsequent evolution of this dual oscillator model for the circadian clock in the mammalian suprachiasmatic nucleus; and how, despite our increasingly sophisticated view of this multicellular pacemaker, Pittendrigh's binary conception has remained influential in our clock models and metaphors.
Collapse
Affiliation(s)
- Jennifer A Evans
- Department of Biomedical Sciences, College of Health Sciences, Marquette University, Milwaukee, WI, USA.
| | - William J Schwartz
- Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX, USA
- Groningen Institute for Evolutionary Life Sciences, Faculty of Science and Engineering, University of Groningen, Groningen, The Netherlands
| |
Collapse
|
4
|
Wang Z, Yu J, Zhai M, Wang Z, Sheng K, Zhu Y, Wang T, Liu M, Wang L, Yan M, Zhang J, Xu Y, Wang X, Ma L, Hu W, Cheng H. System-level time computation and representation in the suprachiasmatic nucleus revealed by large-scale calcium imaging and machine learning. Cell Res 2024; 34:493-503. [PMID: 38605178 PMCID: PMC11217450 DOI: 10.1038/s41422-024-00956-x] [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: 10/31/2023] [Accepted: 03/28/2024] [Indexed: 04/13/2024] Open
Abstract
The suprachiasmatic nucleus (SCN) is the mammalian central circadian pacemaker with heterogeneous neurons acting in concert while each neuron harbors a self-sustained molecular clockwork. Nevertheless, how system-level SCN signals encode time of the day remains enigmatic. Here we show that population-level Ca2+ signals predict hourly time, via a group decision-making mechanism coupled with a spatially modular time feature representation in the SCN. Specifically, we developed a high-speed dual-view two-photon microscope for volumetric Ca2+ imaging of up to 9000 GABAergic neurons in adult SCN slices, and leveraged machine learning methods to capture emergent properties from multiscale Ca2+ signals as a whole. We achieved hourly time prediction by polling random cohorts of SCN neurons, reaching 99.0% accuracy at a cohort size of 900. Further, we revealed that functional neuron subtypes identified by contrastive learning tend to aggregate separately in the SCN space, giving rise to bilaterally symmetrical ripple-like modular patterns. Individual modules represent distinctive time features, such that a module-specifically learned time predictor can also accurately decode hourly time from random polling of the same module. These findings open a new paradigm in deciphering the design principle of the biological clock at the system level.
Collapse
Affiliation(s)
- Zichen Wang
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
- Research Unit of Mitochondria in Brain Diseases, Chinese Academy of Medical Sciences, PKU-Nanjing Institute of Translational Medicine, Nanjing, Jiangsu, China
| | - Jing Yu
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
- Research Unit of Mitochondria in Brain Diseases, Chinese Academy of Medical Sciences, PKU-Nanjing Institute of Translational Medicine, Nanjing, Jiangsu, China
| | - Muyue Zhai
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
| | - Zehua Wang
- Wangxuan Institute of Computer Technology, Peking University, Beijing, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Kaiwen Sheng
- Beijing Academy of Artificial Intelligence, Beijing, China
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Yu Zhu
- Beijing Academy of Artificial Intelligence, Beijing, China
| | - Tianyu Wang
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
| | - Mianzhi Liu
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
| | - Lu Wang
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
| | - Miao Yan
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
| | - Jue Zhang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
- College of Engineering, Peking University, Beijing, China
| | - Ying Xu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Cambridge-Su Genomic Resource Center, Medical School of Soochow University, Suzhou, Jiangsu, China
| | - Xianhua Wang
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China
- Research Unit of Mitochondria in Brain Diseases, Chinese Academy of Medical Sciences, PKU-Nanjing Institute of Translational Medicine, Nanjing, Jiangsu, China
| | - Lei Ma
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China.
- Beijing Academy of Artificial Intelligence, Beijing, China.
| | - Wei Hu
- Wangxuan Institute of Computer Technology, Peking University, Beijing, China.
| | - Heping Cheng
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, College of Future Technology, Peking University, Beijing, China.
- Research Unit of Mitochondria in Brain Diseases, Chinese Academy of Medical Sciences, PKU-Nanjing Institute of Translational Medicine, Nanjing, Jiangsu, China.
| |
Collapse
|
5
|
Schmal C. The seasons within: a theoretical perspective on photoperiodic entrainment and encoding. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024; 210:549-564. [PMID: 37659985 PMCID: PMC11226496 DOI: 10.1007/s00359-023-01669-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 08/11/2023] [Accepted: 08/16/2023] [Indexed: 09/04/2023]
Abstract
Circadian clocks are internal timing devices that have evolved as an adaption to the omnipresent natural 24 h rhythmicity of daylight intensity. Properties of the circadian system are photoperiod dependent. The phase of entrainment varies systematically with season. Plastic photoperiod-dependent re-arrangements in the mammalian circadian core pacemaker yield an internal representation of season. Output pathways of the circadian clock regulate photoperiodic responses such as flowering time in plants or hibernation in mammals. Here, we review the concepts of seasonal entrainment and photoperiodic encoding. We introduce conceptual phase oscillator models as their high level of abstraction, but, yet, intuitive interpretation of underlying parameters allows for a straightforward analysis of principles that determine entrainment characteristics. Results from this class of models are related and discussed in the context of more complex conceptual amplitude-phase oscillators as well as contextual molecular models that take into account organism, tissue, and cell-type-specific details.
Collapse
Affiliation(s)
- Christoph Schmal
- Institute for Theoretical Biology, Humboldt-Universität zu Berlin, Philippstr. 13, 10115, Berlin, Germany.
| |
Collapse
|
6
|
Cheong JH, Qiu X, Liu Y, Krach E, Guo Y, Bhusal S, Schüttler HB, Arnold J, Mao L. The clock in growing hyphae and their synchronization in Neurospora crassa. Commun Biol 2024; 7:735. [PMID: 38890525 PMCID: PMC11189396 DOI: 10.1038/s42003-024-06429-6] [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: 04/26/2023] [Accepted: 06/07/2024] [Indexed: 06/20/2024] Open
Abstract
Utilizing a microfluidic chip with serpentine channels, we inoculated the chip with an agar plug with Neurospora crassa mycelium and successfully captured individual hyphae in channels. For the first time, we report the presence of an autonomous clock in hyphae. Fluorescence of a mCherry reporter gene driven by a clock-controlled gene-2 promoter (ccg-2p) was measured simultaneously along hyphae every half an hour for at least 6 days. We entrained single hyphae to light over a wide range of day lengths, including 6,12, 24, and 36 h days. Hyphae tracked in individual serpentine channels were highly synchronized (K = 0.60-0.78). Furthermore, hyphae also displayed temperature compensation properties, where the oscillation period was stable over a physiological range of temperatures from 24 °C to 30 °C (Q10 = 1.00-1.10). A Clock Tube Model developed could mimic hyphal growth observed in the serpentine chip and provides a mechanism for the stable banding patterns seen in race tubes at the macroscopic scale and synchronization through molecules riding the growth wave in the device.
Collapse
Affiliation(s)
- Jia Hwei Cheong
- Chemistry Department, University of Georgia, Athens, GA, 30602, USA
| | - Xiao Qiu
- Institute of Bioinformatics, University of Georgia, Athens, GA, 30602, USA
| | - Yang Liu
- Chemistry Department, University of Georgia, Athens, GA, 30602, USA
| | - Emily Krach
- Genetics Department, University of Georgia, Athens, GA, 30602, USA
| | - Yinping Guo
- Genetics Department, University of Georgia, Athens, GA, 30602, USA
| | - Shishir Bhusal
- Department of Physics and Astronomy, University of Georgia, Athens, GA, 30602, USA
| | | | - Jonathan Arnold
- Genetics Department, University of Georgia, Athens, GA, 30602, USA.
| | - Leidong Mao
- School of Electrical and Computer Engineering, College of Engineering, University of Georgia, Athens, GA, 30602, USA
| |
Collapse
|
7
|
Czeisler MÉ, Shan Y, Schalek R, Berger DR, Suissa-Peleg A, Takahashi JS, Lichtman JW. Extensive soma-soma plate-like contact sites (ephapses) connect suprachiasmatic nucleus neurons. J Comp Neurol 2024; 532:e25624. [PMID: 38896499 PMCID: PMC11419332 DOI: 10.1002/cne.25624] [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: 09/11/2022] [Revised: 03/30/2024] [Accepted: 04/29/2024] [Indexed: 06/21/2024]
Abstract
The hypothalamic suprachiasmatic nucleus (SCN) is the central pacemaker for mammalian circadian rhythms. As such, this ensemble of cell-autonomous neuronal oscillators with divergent periods must maintain coordinated oscillations. To investigate ultrastructural features enabling such synchronization, 805 coronal ultrathin sections of mouse SCN tissue were imaged with electron microscopy and aligned into a volumetric stack, from which selected neurons within the SCN core were reconstructed in silico. We found that clustered SCN core neurons were physically connected to each other via multiple large soma-to-soma plate-like contacts. In some cases, a sliver of a glial process was interleaved. These contacts were large, covering on average ∼21% of apposing neuronal somata. It is possible that contacts may be the electrophysiological substrate for synchronization between SCN neurons. Such plate-like contacts may explain why the synchronization of SCN neurons is maintained even when chemical synaptic transmission or electrical synaptic transmission via gap junctions is blocked. Such ephaptic contact-mediated synchronization among nearby neurons may therefore contribute to the wave-like oscillations of circadian core clock genes and calcium signals observed in the SCN.
Collapse
Affiliation(s)
- Mark É. Czeisler
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Yongli Shan
- Department of Neuroscience, Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9111, USA
| | - Richard Schalek
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Daniel R. Berger
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Adi Suissa-Peleg
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Joseph S. Takahashi
- Department of Neuroscience, Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9111, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390-9111, USA
| | - Jeff W. Lichtman
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| |
Collapse
|
8
|
Bonnefont X. Cell Signaling in the Circadian Pacemaker: New Insights from in vivo Imaging. Neuroendocrinology 2024:1-8. [PMID: 38754404 DOI: 10.1159/000539344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 05/12/2024] [Indexed: 05/18/2024]
Abstract
BACKGROUND "One for all, and all for one," the famous rallying cry of the Three Musketeers, in Alexandre Dumas's popular novel, certainly applies to the 20,000 cells composing the suprachiasmatic nuclei (SCN). These cells work together to form the central clock that coordinates body rhythms in tune with the day-night cycle. Like virtually every body cell, individual SCN cells exhibit autonomous circadian oscillations, but this rhythmicity only reaches a high level of precision and robustness when the cells are coupled with their neighbors. Therefore, understanding the functional network organization of SCN cells beyond their core rhythmicity is an important issue in circadian biology. SUMMARY The present review summarizes the main results from our recent study demonstrating the feasibility of recording SCN cells in freely moving mice and the significance of variations in intracellular calcium over several timescales. KEY MESSAGE We discuss how in vivo imaging at the cell level will be pivotal to interrogate the mammalian master clock, in an integrated context that preserves the SCN network organization, with intact inputs and outputs.
Collapse
Affiliation(s)
- Xavier Bonnefont
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
- BioCampus Montpellier, Université de Montpellier, CNRS, INSERM, Montpellier, France
| |
Collapse
|
9
|
Sumová A, Sládek M. Circadian Disruption as a Risk Factor for Development of Cardiovascular and Metabolic Disorders - From Animal Models to Human Population. Physiol Res 2024; 73:S321-S334. [PMID: 38634651 PMCID: PMC11412342 DOI: 10.33549/physiolres.935304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024] Open
Abstract
The lifestyle of human society is drifting apart from the natural environmental cycles that have influenced it since its inception. These cycles were fundamental in structuring the daily lives of people in the pre-industrial era, whether they were seasonal or daily. Factors that disrupt the regularity of human behaviour and its alignment with solar cycles, such as late night activities accompanied with food intake, greatly disturb the internal temporal organization in the body. This is believed to contribute to the rise of the so-called diseases of civilization. In this review, we discuss the connection between misalignment in daily (circadian) regulation and its impact on health, with a focus on cardiovascular and metabolic disorders. Our aim is to review selected relevant research findings from laboratory and human studies to assess the extent of evidence for causality between circadian clock disruption and pathology. Keywords: Circadian clock, Chronodisruption, Metabolism, Cardiovascular disorders, Spontaneously hypertensive rat, Human, Social jetlag, Chronotype.
Collapse
Affiliation(s)
- A Sumová
- Laboratory of Biological Rhythms, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
| | | |
Collapse
|
10
|
Smyllie NJ, Hastings MH, Patton AP. Neuron-Astrocyte Interactions and Circadian Timekeeping in Mammals. Neuroscientist 2024:10738584241245307. [PMID: 38602223 DOI: 10.1177/10738584241245307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Almost every facet of our behavior and physiology varies predictably over the course of day and night, anticipating and adapting us to their associated opportunities and challenges. These rhythms are driven by endogenous biological clocks that, when deprived of environmental cues, can continue to oscillate within a period of approximately 1 day, hence circa-dian. Normally, retinal signals synchronize them to the cycle of light and darkness, but disruption of circadian organization, a common feature of modern lifestyles, carries considerable costs to health. Circadian timekeeping pivots around a cell-autonomous molecular clock, widely expressed across tissues. These cellular timers are in turn synchronized by the principal circadian clock of the brain: the hypothalamic suprachiasmatic nucleus (SCN). Intercellular signals make the SCN network a very powerful pacemaker. Previously, neurons were considered the sole SCN timekeepers, with glial cells playing supportive roles. New discoveries have revealed, however, that astrocytes are active partners in SCN network timekeeping, with their cell-autonomous clock regulating extracellular glutamate and GABA concentrations to control circadian cycles of SCN neuronal activity. Here, we introduce circadian timekeeping at the cellular and SCN network levels before focusing on the contributions of astrocytes and their mutual interaction with neurons in circadian control in the brain.
Collapse
Affiliation(s)
- Nicola J Smyllie
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Andrew P Patton
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| |
Collapse
|
11
|
Zuo Y, Ning N, Qiao GC, Wu JH, Bao JH, Zhang XY, Bai J, Wu FH, Liu Y, Yu Q, Hu SG. Floating-Point Approximation Enabling Cost-Effective and High-Precision Digital Implementation of FitzHugh-Nagumo Neural Networks. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2024; 18:347-360. [PMID: 37878421 DOI: 10.1109/tbcas.2023.3327496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
The study of neuron interactions and hardware implementations are crucial research directions in neuroscience, particularly in developing large-scale biological neural networks. The FitzHugh-Nagumo (FHN) model is a popular neuron model with highly biological plausibility, but its complexity makes it difficult to apply at scale. This paper presents a cost-saving and improved precision approximation algorithm for the digital implementation of the FHN model. By converting the computational data into floating-point numbers, the original multiplication calculations are replaced by adding the floating-point exponent part and fitting the mantissa part with piecewise linear. In the hardware implementation, shifters and adders are used, greatly reducing resource overhead. Implementing FHN neurons by this approximation calculations on FPGA reduces the normalized root mean square error (RMSE) to 3.5% of the state-of-the-art (SOTA) while maintaining a performance overhead ratio improvement of 1.09 times. Compared to implementations based on approximate multipliers, the proposed method achieves a 20% reduction in error at the cost of a 2.8% increase in overhead.This model gained additional biological properties compared to LIF while reducing the deployment scale by only 9%. Furthermore, the hardware implementation of nine coupled circular networks with eight nodes and directional diffusion was carried out to demonstrate the algorithm's effectiveness on neural networks. The error decreased to 60% compared to the single neuron of the SOTA. This hardware-friendly algorithm allows for the low-cost implementation of high-precision hardware simulation, providing a novel perspective for studying large-scale, biologically plausible neural networks.
Collapse
|
12
|
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
|
13
|
Liao M, Gao X, Chen C, Li Q, Guo Q, Huang H, Zhang E, Ju D. Integrated neural tracing and in-situ barcoded sequencing reveals the logic of SCN efferent circuits in regulating circadian behaviors. SCIENCE CHINA. LIFE SCIENCES 2024; 67:518-528. [PMID: 38057622 DOI: 10.1007/s11427-023-2420-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 06/30/2023] [Indexed: 12/08/2023]
Abstract
The circadian clock coordinates rhythms in numerous physiological processes to maintain organismal homeostasis. Since the suprachiasmatic nucleus (SCN) is widely accepted as the circadian pacemaker, it is critical to understand the neural mechanisms by which rhythmic information is transferred from the SCN to peripheral clocks. Here, we present the first comprehensive map of SCN efferent connections and suggest a molecular logic underlying these projections. The SCN projects broadly to most major regions of the brain, rather than solely to the hypothalamus and thalamus. The efferent projections from different subtypes of SCN neurons vary in distance and intensity, and blocking synaptic transmission of these circuits affects circadian rhythms in locomotion and feeding to different extents. We also developed a barcoding system to integrate retrograde tracing with in-situ sequencing, allowing us to link circuit anatomy and spatial patterns of gene expression. Analyses using this system revealed that brain regions functioning downstream of the SCN receive input from multiple neuropeptidergic cell types within the SCN, and that individual SCN neurons generally project to a single downstream brain region. This map of SCN efferent connections provides a critical foundation for future investigations into the neural circuits underlying SCN-mediated rhythms in physiology. Further, our new barcoded tracing method provides a tool for revealing the molecular logic of neuronal circuits within heterogeneous brain regions.
Collapse
Affiliation(s)
- Meimei Liao
- College of Biological Sciences, China Agriculture University, Beijing, 100193, China
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Xinwei Gao
- Chinese Institute for Brain Research, Beijing, 102206, China
| | - Chen Chen
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Qi Li
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
- Tsinghua Institute of Multidisciplinar^ Biomedical Research, Tsinghua University, Beijing, 102206, China
| | - Qingchun Guo
- Chinese Institute for Brain Research, Beijing, 102206, China
- School of Biomedical Engineering, Capital Medical University, Beijing, 100069, China
| | - He Huang
- Department of Anesthesiology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, 401336, China
| | - Erquan Zhang
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
- Tsinghua Institute of Multidisciplinar^ Biomedical Research, Tsinghua University, Beijing, 102206, China
| | - Dapeng Ju
- Department of Anesthesiology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, 401336, China.
| |
Collapse
|
14
|
Stengl M, Schneider AC. Contribution of membrane-associated oscillators to biological timing at different timescales. Front Physiol 2024; 14:1243455. [PMID: 38264332 PMCID: PMC10803594 DOI: 10.3389/fphys.2023.1243455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 12/12/2023] [Indexed: 01/25/2024] Open
Abstract
Environmental rhythms such as the daily light-dark cycle selected for endogenous clocks. These clocks predict regular environmental changes and provide the basis for well-timed adaptive homeostasis in physiology and behavior of organisms. Endogenous clocks are oscillators that are based on positive feedforward and negative feedback loops. They generate stable rhythms even under constant conditions. Since even weak interactions between oscillators allow for autonomous synchronization, coupling/synchronization of oscillators provides the basis of self-organized physiological timing. Amongst the most thoroughly researched clocks are the endogenous circadian clock neurons in mammals and insects. They comprise nuclear clockworks of transcriptional/translational feedback loops (TTFL) that generate ∼24 h rhythms in clock gene expression entrained to the environmental day-night cycle. It is generally assumed that this TTFL clockwork drives all circadian oscillations within and between clock cells, being the basis of any circadian rhythm in physiology and behavior of organisms. Instead of the current gene-based hierarchical clock model we provide here a systems view of timing. We suggest that a coupled system of autonomous TTFL and posttranslational feedback loop (PTFL) oscillators/clocks that run at multiple timescales governs adaptive, dynamic homeostasis of physiology and behavior. We focus on mammalian and insect neurons as endogenous oscillators at multiple timescales. We suggest that neuronal plasma membrane-associated signalosomes constitute specific autonomous PTFL clocks that generate localized but interlinked oscillations of membrane potential and intracellular messengers with specific endogenous frequencies. In each clock neuron multiscale interactions of TTFL and PTFL oscillators/clocks form a temporally structured oscillatory network with a common complex frequency-band comprising superimposed multiscale oscillations. Coupling between oscillator/clock neurons provides the next level of complexity of an oscillatory network. This systemic dynamic network of molecular and cellular oscillators/clocks is suggested to form the basis of any physiological homeostasis that cycles through dynamic homeostatic setpoints with a characteristic frequency-band as hallmark. We propose that mechanisms of homeostatic plasticity maintain the stability of these dynamic setpoints, whereas Hebbian plasticity enables switching between setpoints via coupling factors, like biogenic amines and/or neuropeptides. They reprogram the network to a new common frequency, a new dynamic setpoint. Our novel hypothesis is up for experimental challenge.
Collapse
Affiliation(s)
- Monika Stengl
- Department of Biology, Animal Physiology/Neuroethology, University of Kassel, Kassel, Germany
| | | |
Collapse
|
15
|
Britz J, Ojo E, Haque N, Dhukhwa A, Hascup ER, Hascup KN, Tischkau SA. Sex-Dependent Effects of Chronic Circadian Disruption in AβPP/PS1 Mice. J Alzheimers Dis 2024; 97:855-870. [PMID: 38143343 PMCID: PMC10860643 DOI: 10.3233/jad-230089] [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: 12/26/2023]
Abstract
BACKGROUND Chronic disruption of the circadian timing system, often reflected as a loss of restful sleep, also includes myriad other pathophysiological effects. OBJECTIVE The current study examined how chronic circadian disruption (CD) could contribute to pathology and rate of progression in the AβPP/PS1 mouse model of Alzheimer's disease (AD). METHODS A chronic CD was imposed until animals reached 6 or 12 months of age in AβPP/PS1 and C57BL/6J control mice. Home cage activity was monitored for a period of 3-4 weeks prior to the endpoint along with a single timepoint measure of glucose sensitivity. To assess long term effects of CD on the AD phenotype, animals were re-entrained to a no disruption (ND) schedule just prior to the endpoint, after which a Morris water maze (MWM) was used to assess spatial learning and memory. RESULTS Dampening of nighttime activity levels occurred in disrupted animals, and female animals demonstrated a greater adaptability to CD. Diminished arginine vasopressin (AVP) and vasoactive intestinal peptide (VIP) levels in the suprachiasmatic nucleus (SCN) of 12-month male AβPP/PS1 exposed to the CD paradigm were observed, potentially accounting for the diminished re-entrainment response. Similarly, CD worsened performance in the MWM in 12-month male AβPP/PS1 animals, whereas no effect was seen in females. CONCLUSIONS Collectively, these findings show that exposure to chronic CD impairs circadian behavioral patterns and cognitive phenotypes of AβPP/PS1 mouse model in a sex-dependent manner.
Collapse
Affiliation(s)
- Jesse Britz
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Emmanuel Ojo
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Nazmul Haque
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Asmita Dhukhwa
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Erin R. Hascup
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
- Department of Neurology, Dale and Deborah Smith Center for Alzheimer’s Research and Treatment, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Kevin N. Hascup
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
- Department of Neurology, Dale and Deborah Smith Center for Alzheimer’s Research and Treatment, Southern Illinois University School of Medicine, Springfield, IL, USA
- Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Shelley A. Tischkau
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
- Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, USA
| |
Collapse
|
16
|
Kennedy KE, Abenza JF, Rossetti L, Trepat X, Villoslada P, Garcia-Ojalvo J. Parametric modeling of mechanical effects on circadian oscillators. CHAOS (WOODBURY, N.Y.) 2024; 34:013135. [PMID: 38260936 DOI: 10.1063/5.0164829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 12/19/2023] [Indexed: 01/24/2024]
Abstract
Circadian rhythms are archetypal examples of nonlinear oscillations. While these oscillations are usually attributed to circuits of biochemical interactions among clock genes and proteins, recent experimental studies reveal that they are also affected by the cell's mechanical environment. Here, we extend a standard biochemical model of circadian rhythmicity to include mechanical effects in a parametric manner. Using experimental observations to constrain the model, we suggest specific ways in which the mechanical signal might affect the clock. Additionally, a bifurcation analysis of the system predicts that these mechanical signals need to be within an optimal range for circadian oscillations to occur.
Collapse
Affiliation(s)
- Keith E Kennedy
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona Biomedical Research Park, 08003 Barcelona, Spain
| | - Juan F Abenza
- Institute for Bioengineering of Catalonia, Barcelona Institute for Science and Technology, 08028 Barcelona, Spain
| | - Leone Rossetti
- Institute for Bioengineering of Catalonia, Barcelona Institute for Science and Technology, 08028 Barcelona, Spain
| | - Xavier Trepat
- Institute for Bioengineering of Catalonia, Barcelona Institute for Science and Technology, 08028 Barcelona, Spain
- Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 08028 Barcelona, Spain
| | - Pablo Villoslada
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona Biomedical Research Park, 08003 Barcelona, Spain
- Hospital del Mar Medical Research Institute, Barcelona Biomedical Research Park, 08003 Barcelona, Spain
| | - Jordi Garcia-Ojalvo
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona Biomedical Research Park, 08003 Barcelona, Spain
| |
Collapse
|
17
|
Venegas-Pineda LG, Jardón-Kojakhmetov H, Cao M. Stable chimera states: A geometric singular perturbation approach. CHAOS (WOODBURY, N.Y.) 2023; 33:113123. [PMID: 37972302 DOI: 10.1063/5.0142122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 10/23/2023] [Indexed: 11/19/2023]
Abstract
Over the past decades, chimera states have attracted considerable attention given their unexpected symmetry-breaking spatiotemporal nature and simultaneously exhibiting synchronous and incoherent behaviors under specific conditions. Despite relevant precursory results of such unforeseen states for diverse physical and topological configurations, there remain structures and mechanisms yet to be unveiled. In this work, using mean-field techniques, we analyze a multilayer network composed of two populations of heterogeneous Kuramoto phase oscillators with coevolutive coupling strengths. Moreover, we employ the geometric singular perturbation theory through the inclusion of a time-scale separation between the dynamics of the network elements and the adaptive coupling strength connecting them, gaining a better insight into the behavior of the system from a fast-slow dynamics perspective. Consequently, we derive the necessary and sufficient condition to produce stable chimera states when considering a coevolutionary intercoupling strength. Additionally, under the aforementioned constraint and with a suitable adaptive law election, it is possible to generate intriguing patterns, such as persistent breathing chimera states. Thereafter, we analyze the geometric properties of the mean-field system with a coevolutionary intracoupling strength and demonstrate the production of stable chimera states. Next, we give arguments for the presence of such patterns in the associated network under specific conditions. Finally, relaxation oscillations and canard cycles, seemingly related to breathing chimeras, are numerically produced under identified conditions due to the geometry of our system.
Collapse
Affiliation(s)
- Luis Guillermo Venegas-Pineda
- Bernoulli Institute for Mathematics, Computer Science and Artificial Intelligence, University of Groningen, Nijenborgh 9, 9700 AK Groningen, The Netherlands
| | - Hildeberto Jardón-Kojakhmetov
- Bernoulli Institute for Mathematics, Computer Science and Artificial Intelligence, University of Groningen, Nijenborgh 9, 9700 AK Groningen, The Netherlands
| | - Ming Cao
- Engineering and Technology Institute Groningen, University of Groningen, Nijenborgh 4, 9700 AE Groningen, The Netherlands
| |
Collapse
|
18
|
Onodera K, Tsuno Y, Hiraoka Y, Tanaka K, Maejima T, Mieda M. In vivo recording of the circadian calcium rhythm in Prokineticin 2 neurons of the suprachiasmatic nucleus. Sci Rep 2023; 13:16974. [PMID: 37813987 PMCID: PMC10562406 DOI: 10.1038/s41598-023-44282-5] [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: 05/15/2023] [Accepted: 10/05/2023] [Indexed: 10/11/2023] Open
Abstract
Prokineticin 2 (Prok2) is a small protein expressed in a subpopulation of neurons in the suprachiasmatic nucleus (SCN), the primary circadian pacemaker in mammals. Prok2 has been implicated as a candidate output molecule from the SCN to control multiple circadian rhythms. Genetic manipulation specific to Prok2-producing neurons would be a powerful approach to understanding their function. Here, we report the generation of Prok2-tTA knock-in mice expressing the tetracycline transactivator (tTA) specifically in Prok2 neurons and an application of these mice to in vivo recording of Ca2+ rhythms in these neurons. First, the specific and efficient expression of tTA in Prok2 neurons was verified by crossing the mice with EGFP reporter mice. Prok2-tTA mice were then used to express a fluorescent Ca2+ sensor protein to record the circadian Ca2+ rhythm in SCN Prok2 neurons in vivo. Ca2+ in these cells showed clear circadian rhythms in both light-dark and constant dark conditions, with their peaks around midday. Notably, the hours of high Ca2+ nearly coincided with the rest period of the behavioral rhythm. These observations fit well with the predicted function of Prok2 neurons as a candidate output pathway of the SCN by suppressing locomotor activity during both daytime and subjective daytime.
Collapse
Affiliation(s)
- Kaito Onodera
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa, 920-8640, Japan
| | - Yusuke Tsuno
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa, 920-8640, Japan
| | - Yuichi Hiraoka
- Laboratory of Molecular Neuroscience, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Kohichi Tanaka
- Laboratory of Molecular Neuroscience, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Takashi Maejima
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa, 920-8640, Japan
| | - Michihiro Mieda
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa, 920-8640, Japan.
| |
Collapse
|
19
|
Dutta S, Mondal A, Kundu P, Khanra P, Pal P, Hens C. Impact of phase lag on synchronization in frustrated Kuramoto model with higher-order interactions. Phys Rev E 2023; 108:034208. [PMID: 37849147 DOI: 10.1103/physreve.108.034208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 08/25/2023] [Indexed: 10/19/2023]
Abstract
The study of first order transition (explosive synchronization) in an ensemble (network) of coupled oscillators has been the topic of paramount interest among the researchers for more than one decade. Several frameworks have been proposed to induce explosive synchronization in a network and it has been reported that phase frustration in a network usually suppresses first order transition in the presence of pairwise interactions among the oscillators. However, on the contrary, by considering networks of phase frustrated coupled oscillators in the presence of higher-order interactions (up to 2-simplexes) we show here, under certain conditions, phase frustration can promote explosive synchronization in a network. A low-dimensional model of the network in the thermodynamic limit is derived using the Ott-Antonsen ansatz to explain this surprising result. Analytical treatment of the low-dimensional model, including bifurcation analysis, explains the apparent counter intuitive result quite clearly.
Collapse
Affiliation(s)
- Sangita Dutta
- Department of Mathematics, National Institute of Technology, Durgapur 713209, India
| | - Abhijit Mondal
- Department of Mathematics, National Institute of Technology, Durgapur 713209, India
| | - Prosenjit Kundu
- Dhirubhai Ambani Institute of Information and Communication Technology, Gandhinagar, Gujarat 382007, India
| | - Pitambar Khanra
- Department of Mathematics, State University of New York at Buffalo, Buffalo 14260, USA
| | - Pinaki Pal
- Department of Mathematics, National Institute of Technology, Durgapur 713209, India
| | - Chittaranjan Hens
- Center for Computational Natural Science and Bioinformatics, International Institute of Informational Technology, Gachibowli, Hyderabad 500032, India
| |
Collapse
|
20
|
Hibberd TJ, Ramsay S, Spencer-Merris P, Dinning PG, Zagorodnyuk VP, Spencer NJ. Circadian rhythms in colonic function. Front Physiol 2023; 14:1239278. [PMID: 37711458 PMCID: PMC10498548 DOI: 10.3389/fphys.2023.1239278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 08/17/2023] [Indexed: 09/16/2023] Open
Abstract
A rhythmic expression of clock genes occurs within the cells of multiple organs and tissues throughout the body, termed "peripheral clocks." Peripheral clocks are subject to entrainment by a multitude of factors, many of which are directly or indirectly controlled by the light-entrainable clock located in the suprachiasmatic nucleus of the hypothalamus. Peripheral clocks occur in the gastrointestinal tract, notably the epithelia whose functions include regulation of absorption, permeability, and secretion of hormones; and in the myenteric plexus, which is the intrinsic neural network principally responsible for the coordination of muscular activity in the gut. This review focuses on the physiological circadian variation of major colonic functions and their entraining mechanisms, including colonic motility, absorption, hormone secretion, permeability, and pain signalling. Pathophysiological states such as irritable bowel syndrome and ulcerative colitis and their interactions with circadian rhythmicity are also described. Finally, the classic circadian hormone melatonin is discussed, which is expressed in the gut in greater quantities than the pineal gland, and whose exogenous use has been of therapeutic interest in treating colonic pathophysiological states, including those exacerbated by chronic circadian disruption.
Collapse
Affiliation(s)
- Timothy J. Hibberd
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Stewart Ramsay
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | | | - Phil G. Dinning
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
- Colorectal Surgical Unit, Division of Surgery, Flinders Medical Centre, Adelaide, SA, Australia
| | | | - Nick J. Spencer
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| |
Collapse
|
21
|
Tsuno Y, Peng Y, Horike SI, Wang M, Matsui A, Yamagata K, Sugiyama M, Nakamura TJ, Daikoku T, Maejima T, Mieda M. In vivo recording of suprachiasmatic nucleus dynamics reveals a dominant role of arginine vasopressin neurons in circadian pacesetting. PLoS Biol 2023; 21:e3002281. [PMID: 37643163 PMCID: PMC10465001 DOI: 10.1371/journal.pbio.3002281] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 07/28/2023] [Indexed: 08/31/2023] Open
Abstract
The central circadian clock of the suprachiasmatic nucleus (SCN) is a network consisting of various types of neurons and glial cells. Individual cells have the autonomous molecular machinery of a cellular clock, but their intrinsic periods vary considerably. Here, we show that arginine vasopressin (AVP) neurons set the ensemble period of the SCN network in vivo to control the circadian behavior rhythm. Artificial lengthening of cellular periods by deleting casein kinase 1 delta (CK1δ) in the whole SCN lengthened the free-running period of behavior rhythm to an extent similar to CK1δ deletion specific to AVP neurons. However, in SCN slices, PER2::LUC reporter rhythms of these mice only partially and transiently recapitulated the period lengthening, showing a dissociation between the SCN shell and core with a period instability in the shell. In contrast, in vivo calcium rhythms of both AVP and vasoactive intestinal peptide (VIP) neurons in the SCN of freely moving mice demonstrated stably lengthened periods similar to the behavioral rhythm upon AVP neuron-specific CK1δ deletion, without changing the phase relationships between each other. Furthermore, optogenetic activation of AVP neurons acutely induced calcium increase in VIP neurons in vivo. These results indicate that AVP neurons regulate other SCN neurons, such as VIP neurons, in vivo and thus act as a primary determinant of the SCN ensemble period.
Collapse
Affiliation(s)
- Yusuke Tsuno
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Yubo Peng
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Shin-ichi Horike
- Division of Integrated Omics Research, Research Center for Experimental Modeling of Human Disease, Kanazawa University, Kanazawa, Japan
| | - Mohan Wang
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Ayako Matsui
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Kanato Yamagata
- Child Brain Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Mizuki Sugiyama
- Laboratory of Animal Physiology, School of Agriculture, Meiji University, Kawasaki, Japan
| | - Takahiro J. Nakamura
- Laboratory of Animal Physiology, School of Agriculture, Meiji University, Kawasaki, Japan
| | - Takiko Daikoku
- Division of Animal Disease Model, Research Center for Experimental Modeling of Human Disease, Kanazawa University, Kanazawa, Japan
| | - Takashi Maejima
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Michihiro Mieda
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| |
Collapse
|
22
|
Ocampo-Espindola JL, Nikhil KL, Li JS, Herzog ED, Kiss IZ. Synchronization, clustering, and weak chimeras in a densely coupled transcription-based oscillator model for split circadian rhythms. CHAOS (WOODBURY, N.Y.) 2023; 33:083105. [PMID: 37535024 PMCID: PMC10403273 DOI: 10.1063/5.0156135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 07/08/2023] [Indexed: 08/04/2023]
Abstract
The synchronization dynamics for the circadian gene expression in the suprachiasmatic nucleus is investigated using a transcriptional circadian clock gene oscillator model. With global coupling in constant dark (DD) conditions, the model exhibits a one-cluster phase synchronized state, in dim light (dim LL), bistability between one- and two-cluster states and in bright LL, a two-cluster state. The two-cluster phase synchronized state, where some oscillator pairs synchronize in-phase, and some anti-phase, can explain the splitting of the circadian clock, i.e., generation of two bouts of daily activities with certain species, e.g., with hamsters. The one- and two-cluster states can be reached by transferring the animal from DD or bright LL to dim LL, i.e., the circadian synchrony has a memory effect. The stability of the one- and two-cluster states was interpreted analytically by extracting phase models from the ordinary differential equation models. In a modular network with two strongly coupled oscillator populations with weak intragroup coupling, with appropriate initial conditions, one group is synchronized to the one-cluster state and the other group to the two-cluster state, resulting in a weak-chimera state. Computational modeling suggests that the daily rhythms in sleep-wake depend on light intensity acting on bilateral networks of suprachiasmatic nucleus (SCN) oscillators. Addition of a network heterogeneity (coupling between the left and right SCN) allowed the system to exhibit chimera states. The simulations can guide experiments in the circadian rhythm research to explore the effect of light intensity on the complexities of circadian desynchronization.
Collapse
Affiliation(s)
| | - K. L. Nikhil
- Department of Biology, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130-4899, USA
| | - Jr-Shin Li
- Department of Electrical and Systems Engineering, Washington University in St Louis, 1 Brookings Drive, St. Louis, Missouri 63130, USA
| | - Erik D. Herzog
- Department of Biology, Washington University in St. Louis, One Brookings Drive, St. Louis, Missouri 63130-4899, USA
| | - István Z. Kiss
- Department of Chemistry, Saint Louis University, 3501 Laclede Ave., St. Louis, Missouri 63103, USA
| |
Collapse
|
23
|
Collery A, Browne JA, O'Brien C, Sheridan JT, Murphy BA. Optimised Stable Lighting Strengthens Circadian Clock Gene Rhythmicity in Equine Hair Follicles. Animals (Basel) 2023; 13:2335. [PMID: 37508112 PMCID: PMC10376498 DOI: 10.3390/ani13142335] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
Hair follicles (HF) represent a useful tissue for monitoring the circadian clock in mammals. Irregular light exposure causes circadian disruption and represents a welfare concern for stabled horses. We aimed to evaluate the impact of two stable lighting regimes on circadian clock gene rhythmicity in HF from racehorses. Two groups of five Thoroughbred racehorses in training at a commercial racehorse yard were exposed to standard incandescent light or a customized LED lighting system. The control group received light from incandescent bulbs used according to standard yard practice. The treatment group received timed, blue-enriched white LED light by day and dim red LED light at night. On weeks 0 and 20, mane hairs were collected at 4 h intervals for 24 h. Samples were stored in RNAlater at -20 °C. RNA was isolated and samples interrogated by quantitative PCR for the core clock genes: ARNTL, CRY1, PER1, PER2, NR1D2, and the clock-controlled gene DBP. Cosinor analyses revealed 24 h rhythmicity for NR1D2 and PER2 and approached significance for CRY1 (p = 0.013, p = 0.013, and p = 0.051, respectively) in week 20 in the treatment group only. No rhythmicity was detected in week 0 or in week 20 in the HF of control horses. Results suggest that lighting practices in racehorse stables may be improved to better stimulate optimum functioning of the circadian system.
Collapse
Affiliation(s)
- Aileen Collery
- School of Agriculture and Food Science, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
| | - John A Browne
- School of Agriculture and Food Science, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
| | | | - John T Sheridan
- School of Electrical, Electronic and Mechanical Engineering, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
| | - Barbara A Murphy
- School of Agriculture and Food Science, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
| |
Collapse
|
24
|
Patton AP, Morris EL, McManus D, Wang H, Li Y, Chin JW, Hastings MH. Astrocytic control of extracellular GABA drives circadian timekeeping in the suprachiasmatic nucleus. Proc Natl Acad Sci U S A 2023; 120:e2301330120. [PMID: 37186824 PMCID: PMC10214171 DOI: 10.1073/pnas.2301330120] [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] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 04/12/2023] [Indexed: 05/17/2023] Open
Abstract
The hypothalamic suprachiasmatic nucleus (SCN) is the master mammalian circadian clock. Its cell-autonomous timing mechanism, a transcriptional/translational feedback loop (TTFL), drives daily peaks of neuronal electrical activity, which in turn control circadian behavior. Intercellular signals, mediated by neuropeptides, synchronize and amplify TTFL and electrical rhythms across the circuit. SCN neurons are GABAergic, but the role of GABA in circuit-level timekeeping is unclear. How can a GABAergic circuit sustain circadian cycles of electrical activity, when such increased neuronal firing should become inhibitory to the network? To explore this paradox, we show that SCN slices expressing the GABA sensor iGABASnFR demonstrate a circadian oscillation of extracellular GABA ([GABA]e) that, counterintuitively, runs in antiphase to neuronal activity, with a prolonged peak in circadian night and a pronounced trough in circadian day. Resolving this unexpected relationship, we found that [GABA]e is regulated by GABA transporters (GATs), with uptake peaking during circadian day, hence the daytime trough and nighttime peak. This uptake is mediated by the astrocytically expressed transporter GAT3 (Slc6a11), expression of which is circadian-regulated, being elevated in daytime. Clearance of [GABA]e in circadian day facilitates neuronal firing and is necessary for circadian release of the neuropeptide vasoactive intestinal peptide, a critical regulator of TTFL and circuit-level rhythmicity. Finally, we show that genetic complementation of the astrocytic TTFL alone, in otherwise clockless SCN, is sufficient to drive [GABA]e rhythms and control network timekeeping. Thus, astrocytic clocks maintain the SCN circadian clockwork by temporally controlling GABAergic inhibition of SCN neurons.
Collapse
Affiliation(s)
- Andrew P. Patton
- Neurobiology Division, Medical Research Council Laboratory of Molecular Biology, CambridgeCB2 0QH, United Kingdom
| | - Emma L. Morris
- Neurobiology Division, Medical Research Council Laboratory of Molecular Biology, CambridgeCB2 0QH, United Kingdom
| | - David McManus
- Neurobiology Division, Medical Research Council Laboratory of Molecular Biology, CambridgeCB2 0QH, United Kingdom
| | - Huan Wang
- State Key Laboratory of Membrane Biology, Peking University, School of Life Sciences, 100871Beijing, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University, School of Life Sciences, 100871Beijing, China
| | - Jason W. Chin
- PNAC Division, Medical Research Council Laboratory of Molecular Biology, CambridgeCB2 0QH, United Kingdom
| | - Michael H. Hastings
- Neurobiology Division, Medical Research Council Laboratory of Molecular Biology, CambridgeCB2 0QH, United Kingdom
| |
Collapse
|
25
|
Nakazawa K, Matsuo M, Kimura N, Numano R. Restricted Feeding Resets the Peripheral Clocks of the Digestive System. Biomedicines 2023; 11:biomedicines11051463. [PMID: 37239134 DOI: 10.3390/biomedicines11051463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 05/08/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
All organisms maintain an internal clock that matches the Earth's rotation over a period of 24 h, known as the circadian rhythm. Previously, we established Period1 luciferase (Per1::luc) transgenic (Tg) mice in order to monitor the expression rhythms of the Per1 clock gene in each tissue in real time using a bioluminescent reporter. The Per1 gene is a known key molecular regulator of the mammalian clock system in the autonomous central clock in the suprachiasmatic nucleus (SCN), and the peripheral tissues. Per1::luc Tg mice were used as a biosensing system of circadian rhythms. They were maintained by being fed ad lib (FF) and subsequently subjected to 4 hour (4 h) restricted feeding (RF) during the rest period under light conditions in order to examine whether the peripheral clocks of different parts in the digestive tract could be entrained. The peak points of the bioluminescent rhythms in the Per1::luc Tg mouse tissue samples were analyzed via cosine fitting. The bioluminescent rhythms of the cultured peripheral tissues of the esophagus and the jejunum exhibited phase shift from 5 to 11 h during RF, whereas those of the SCN tissue remained unchanged for 7 days during RF. We examined whether RF for 4 h during the rest period in light conditions could reset the activity rhythms, the central clock in the SCN, and the peripheral clock in the different points in the gastrointestinal tract. The fasting signals during RF did not entrain the SCN, but they did entrain each peripheral clock of the digestive system, the esophagus, and the jejunum. During RF for 7 days, the peak time of the esophagus tended to return to that of the FF control, unlike that of the jejunum; hence, the esophagus was regulated more strongly under the control of the cultured SCN compared to the jejunum. Thus, the peripheral clocks of the digestive system can entrain their molecular clock rhythms via RF-induced fasting signals in each degree, independently from the SCN.
Collapse
Affiliation(s)
- Kazuo Nakazawa
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
| | - Minako Matsuo
- Institute for Research on Next-Generation Semiconductor and Sensing Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
| | - Naobumi Kimura
- Institute for Research on Next-Generation Semiconductor and Sensing Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
| | - Rika Numano
- Department of Applied Chemistry and Life Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
- Institute for Research on Next-Generation Semiconductor and Sensing Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
| |
Collapse
|
26
|
Masuda K, Kon N, Iizuka K, Fukada Y, Sakurai T, Hirano A. Singularity response reveals entrainment properties in mammalian circadian clock. Nat Commun 2023; 14:2819. [PMID: 37198169 DOI: 10.1038/s41467-023-38392-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 04/28/2023] [Indexed: 05/19/2023] Open
Abstract
Entrainment is characterized by phase response curves (PRCs), which provide a summary of responses to perturbations at each circadian phase. The synchronization of mammalian circadian clocks is accomplished through the receipt of a variety of inputs from both internal and external time cues. A comprehensive comparison of PRCs for various stimuli in each tissue is required. Herein, we demonstrate that PRCs in mammalian cells can be characterized using a recently developed estimation method based on singularity response (SR), which represents the response of desynchronized cellular clocks. We confirmed that PRCs can be reconstructed using single SR measurements and quantified response properties for various stimuli in several cell lines. SR analysis reveals that the phase and amplitude after resetting are distinguishable among stimuli. SRs in tissue slice cultures reveal tissue-specific entrainment properties. These results demonstrate that SRs can be employed to unveil entrainment mechanisms with diverse stimuli in multiscale mammalian clocks.
Collapse
Affiliation(s)
- Kosaku Masuda
- Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-8577, 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
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0032, Japan
- Suntory Rising Stars Encouragement Program in Life Sciences (SunRiSE), 8‑1‑1 Seikadai, Seika‑cho, Soraku‑gun, Kyoto, 619‑0284, Japan
| | - Kosuke Iizuka
- 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
| | - Yoshitaka Fukada
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0032, Japan
- Laboratory of Animal Resources, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Takeshi Sakurai
- Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
| | - Arisa Hirano
- Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
| |
Collapse
|
27
|
Ahern J, Chrobok Ł, Champneys AR, Piggins HD. A new phase model of the spatiotemporal relationships between three circadian oscillators in the brainstem. Sci Rep 2023; 13:5480. [PMID: 37016055 PMCID: PMC10073201 DOI: 10.1038/s41598-023-32315-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/25/2023] [Indexed: 04/06/2023] Open
Abstract
Analysis of ex vivo Per2 bioluminescent rhythm previously recorded in the mouse dorsal vagal complex reveals a characteristic phase relationship between three distinct circadian oscillators. These signals represent core clock gene expression in the area postrema (AP), the nucleus of the solitary tract (NTS) and the ependymal cells surrounding the 4th ventricle (4Vep). Initially, the data suggests a consistent phasing in which the AP peaks first, followed shortly by the NTS, with the 4Vep peaking 8-9 h later. Wavelet analysis reveals that this pattern is not consistently maintained throughout a recording, however, the phase dynamics strongly imply that oscillator interactions are present. A simple phase model of the three oscillators is developed and it suggests that realistic phase dynamics occur between three model oscillators with coupling close to a synchronisation transition. The coupling topology suggests that the AP bidirectionally communicates phase information to the NTS and the 4Vep to synchronise the three structures. A comparison of the model with previous experimental manipulations demonstrates its feasibility to explain DVC circadian phasing. Finally, we show that simulating steadily decaying coupling improves the model's ability to capture experimental phase dynamics.
Collapse
Affiliation(s)
- Jake Ahern
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK
- Engineering Mathematics, University of Bristol, Bristol, BS8 1TW, UK
| | - Łukasz Chrobok
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK
| | - Alan R Champneys
- Engineering Mathematics, University of Bristol, Bristol, BS8 1TW, UK
| | - Hugh D Piggins
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK.
| |
Collapse
|
28
|
Murakami A, Tsuji K, Isoda M, Matsuo M, Abe Y, Yasui M, Okamura H, Tominaga K. Prolonged Light Exposure Induces Circadian Impairment in Aquaporin-4-Knockout Mice. J Biol Rhythms 2023; 38:208-214. [PMID: 36694941 DOI: 10.1177/07487304221146242] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Astrocytes are densely present in the suprachiasmatic nucleus (SCN), which is the master circadian oscillator in mammals, and are presumed to play a key role in circadian oscillation. However, specific astrocytic molecules that regulate the circadian clock are not yet well understood. In our study, we found that the water channel aquaporin-4 (AQP4) was abundantly expressed in SCN astrocytes, and we further examined its circadian role using AQP4-knockout mice. There was no prominent difference in circadian behavioral rhythms between Aqp4-/- and Aqp4+/+ mice subjected to light-dark cycles and constant dark conditions. However, exposure to constant light induced a greater decrease in the Aqp4-/- mice rhythmicity. Although the damped rhythm in long-term constant light recovered after transfer to constant dark conditions in both genotypes, the period until the reappearance of original rhythmicity was severely prolonged in Aqp4-/- mice. In conclusion, AQP4 absence exacerbates the prolonged light-induced impairment of circadian oscillations and delays their recovery to normal rhythmicity.
Collapse
Affiliation(s)
- Atsumi Murakami
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Kouki Tsuji
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Japan
| | - Minako Isoda
- Graduate School of Science, Kyoto University, Sakyo-ku, Japan
| | - Masahiro Matsuo
- Department of Psychiatry, Shiga University Graduate School of Medicine, Otsu, Japan
| | - Yoichiro Abe
- Department of Pharmacology, Keio University School of Medicine, Tokyo, Japan
- Keio University Global Research Institute, Center for Water Biology and Medicine, Tokyo, Japan
| | - Masato Yasui
- Department of Pharmacology, Keio University School of Medicine, Tokyo, Japan
- Keio University Global Research Institute, Center for Water Biology and Medicine, Tokyo, Japan
| | - Hitoshi Okamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyō-ku, Japan
- Department of Neurobiology, Graduate School of Medicine, Kyoto University, Sakyō-ku, Japan
| | - Keiko Tominaga
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| |
Collapse
|
29
|
de Aguiar MAM. Generalized frustration in the multidimensional Kuramoto model. Phys Rev E 2023; 107:044205. [PMID: 37198798 DOI: 10.1103/physreve.107.044205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 03/24/2023] [Indexed: 05/19/2023]
Abstract
The Kuramoto model describes how coupled oscillators synchronize their phases as the intensity of the coupling increases past a threshold. The model was recently extended by reinterpreting the oscillators as particles moving on the surface of unit spheres in a D-dimensional space. Each particle is then represented by a D-dimensional unit vector; for D=2 the particles move on the unit circle and the vectors can be described by a single phase, recovering the original Kuramoto model. This multidimensional description can be further extended by promoting the coupling constant between the particles to a matrix K that acts on the unit vectors. As the coupling matrix changes the direction of the vectors, it can be interpreted as a generalized frustration that tends to hinder synchronization. In a recent paper we studied in detail the role of the coupling matrix for D=2. Here we extend this analysis to arbitrary dimensions. We show that, for identical particles, when the natural frequencies are set to zero, the system converges either to a stationary synchronized state, given by one of the real eigenvectors of K, or to an effective two-dimensional rotation, defined by one of the complex eigenvectors of K. The stability of these states depends on the set eigenvalues and eigenvectors of the coupling matrix, which controls the asymptotic behavior of the system, and therefore, can be used to manipulate these states. When the natural frequencies are not zero, synchronization depends on whether D is even or odd. In even dimensions the transition to synchronization is continuous and rotating states are replaced by active states, where the module of the order parameter oscillates while it rotates. If D is odd the phase transition is discontinuous and active states can be suppressed for some distributions of natural frequencies.
Collapse
Affiliation(s)
- Marcus A M de Aguiar
- Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas, Unicamp 13083-970, Campinas, São Paolo, Brazil
| |
Collapse
|
30
|
Wang Y, Guo H, He F. Circadian disruption: from mouse models to molecular mechanisms and cancer therapeutic targets. Cancer Metastasis Rev 2023; 42:297-322. [PMID: 36513953 DOI: 10.1007/s10555-022-10072-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 11/25/2022] [Indexed: 12/15/2022]
Abstract
The circadian clock is a timekeeping system for numerous biological rhythms that contribute to the regulation of numerous homeostatic processes in humans. Disruption of circadian rhythms influences physiology and behavior and is associated with adverse health outcomes, especially cancer. However, the underlying molecular mechanisms of circadian disruption-associated cancer initiation and development remain unclear. It is essential to construct good circadian disruption models to uncover and validate the detailed molecular clock framework of circadian disruption in cancer development and progression. Mouse models are the most widely used in circadian studies due to their relatively small size, fast reproduction cycle, easy genome manipulation, and economic practicality. Here, we reviewed the current mouse models of circadian disruption, including suprachiasmatic nuclei destruction, genetic engineering, light disruption, sleep deprivation, and other lifestyle factors in our understanding of the crosstalk between circadian rhythms and oncogenic signaling, as well as the molecular mechanisms of circadian disruption that promotes cancer growth. We focused on the discoveries made with the nocturnal mouse, diurnal human being, and cell culture and provided several circadian rhythm-based cancer therapeutic strategies.
Collapse
Affiliation(s)
- Yu Wang
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Haidong Guo
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China.
- Department of Anatomy, School of Basic Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China.
| | - Feng He
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China.
| |
Collapse
|
31
|
Stangherlin A. Ion dynamics and the regulation of circadian cellular physiology. Am J Physiol Cell Physiol 2023; 324:C632-C643. [PMID: 36689675 DOI: 10.1152/ajpcell.00378.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Circadian rhythms in physiology and behavior allow organisms to anticipate the daily environmental changes imposed by the rotation of our planet around its axis. Although these rhythms eventually manifest at the organismal level, a cellular basis for circadian rhythms has been demonstrated. Significant contributors to these cell-autonomous rhythms are daily cycles in gene expression and protein translation. However, recent data revealed cellular rhythms in other biological processes, including ionic currents, ion transport, and cytosolic ion abundance. Circadian rhythms in ion currents sustain circadian variation in action potential firing rate, which coordinates neuronal behavior and activity. Circadian regulation of metal ions abundance and dynamics is implicated in distinct cellular processes, from protein translation to membrane activity and osmotic homeostasis. In turn, studies showed that manipulating ion abundance affects the expression of core clock genes and proteins, suggestive of a close interplay. However, the relationship between gene expression cycles, ion dynamics, and cellular function is still poorly characterized. In this review, I will discuss the mechanisms that generate ion rhythms, the cellular functions they govern, and how they feed back to regulate the core clock machinery.
Collapse
Affiliation(s)
- Alessandra Stangherlin
- Faculty of Medicine and University Hospital Cologne, Cluster of Excellence Cellular Stress Responses in Aging-associated Diseases (CECAD), Institute for Mitochondrial Diseases and Ageing, University of Cologne, Cologne, Germany
| |
Collapse
|
32
|
Kuwano R, Katsura M, Iwata M, Yokosako T, Yoshii T. Pigment-dispersing factor and CCHamide1 in the Drosophila circadian clock network. Chronobiol Int 2023; 40:284-299. [PMID: 36786215 DOI: 10.1080/07420528.2023.2166416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Animals possess a circadian central clock in the brain, where circadian behavioural rhythms are generated. In the fruit fly (Drosophila melanogaster), the central clock comprises a network of approximately 150 clock neurons, which is important for the maintenance of a coherent and robust rhythm. Several neuropeptides involved in the network have been identified, including Pigment-dispersing factor (PDF) and CCHamide1 (CCHa1) neuropeptides. PDF signals bidirectionally to CCHa1-positive clock neurons; thus, the clock neuron groups expressing PDF and CCHa1 interact reciprocally. However, the role of these interactions in molecular and behavioural rhythms remains elusive. In this study, we generated Pdf 01 and CCHa1SK8 double mutants and examined their locomotor activity-related rhythms. The single mutants of Pdf 01 or CCHa1SK8 displayed free-running rhythms under constant dark conditions, whereas approximately 98% of the double mutants were arrhythmic. In light-dark conditions, the evening activity of the double mutants was phase-advanced compared with that of the single mutants. In contrast, both the single and double mutants had diminished morning activity. These results suggest that the effects of the double mutation varied in behavioural parameters. The double and triple mutants of per 01, Pdf 01, and CCHa1SK8 further revealed that PDF signalling plays a role in the suppression of activity during the daytime under a clock-less background. Our results provide insights into the interactions between PDF and CCHa1 signalling and their roles in activity rhythms.
Collapse
Affiliation(s)
- Riko Kuwano
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Maki Katsura
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Mai Iwata
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Tatsuya Yokosako
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Taishi Yoshii
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| |
Collapse
|
33
|
Hitrec T, Petit C, Cryer E, Muir C, Tal N, Fustin JM, Hughes AT, Piggins HD. Timed exercise stabilizes behavioral rhythms but not molecular programs in the brain's suprachiasmatic clock. iScience 2023; 26:106002. [PMID: 36866044 PMCID: PMC9971895 DOI: 10.1016/j.isci.2023.106002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 11/25/2022] [Accepted: 01/13/2023] [Indexed: 01/20/2023] Open
Abstract
Timed daily access to a running-wheel (scheduled voluntary exercise; SVE) synchronizes rodent circadian rhythms and promotes stable, 24h rhythms in animals with genetically targeted impairment of neuropeptide signaling (Vipr2 -/- mice). Here we used RNA-seq and/or qRT-PCR to assess how this neuropeptide signaling impairment as well as SVE shapes molecular programs in the brain clock (suprachiasmatic nuclei; SCN) and peripheral tissues (liver and lung). Compared to Vipr2 +/+ animals, the SCN transcriptome of Vipr2 -/- mice showed extensive dysregulation which included core clock components, transcription factors, and neurochemicals. Furthermore, although SVE stabilized behavioral rhythms in these animals, the SCN transcriptome remained dysregulated. The molecular programs in the lung and liver of Vipr2 -/- mice were partially intact, although their response to SVE differed to that of these peripheral tissues in the Vipr2 +/+ mice. These findings highlight that SVE can correct behavioral abnormalities in circadian rhythms without causing large scale alterations to the SCN transcriptome.
Collapse
Affiliation(s)
- Timna Hitrec
- School of Physiology, Pharmacology, and Neuroscience, Faculty of Life Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Cheryl Petit
- School of Medical Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester M13 9PT, UK
| | - Emily Cryer
- School of Biological Sciences, Faculty of Life Sciences, University of Bristol, Bristol BS8 1TQ, UK
| | - Charlotte Muir
- School of Physiology, Pharmacology, and Neuroscience, Faculty of Life Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Natalie Tal
- School of Medical Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester M13 9PT, UK
| | - Jean-Michel Fustin
- School of Medical Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester M13 9PT, UK
| | - Alun T.L. Hughes
- School of Medical Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester M13 9PT, UK,School of Biological and Environmental Sciences, Faculty of Science, Liverpool John Moores University, Liverpool L3 3AF, UK,Corresponding author
| | - Hugh D. Piggins
- School of Physiology, Pharmacology, and Neuroscience, Faculty of Life Sciences, University of Bristol, Bristol BS8 1TD, UK,School of Medical Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester M13 9PT, UK,Corresponding author
| |
Collapse
|
34
|
Phillips DJ, Blaine S, Wallace NK, Karatsoreos IN. Brain-derived neurotrophic factor Val66Met polymorphism modulates the effects of circadian desynchronization on activity and sleep in male mice. Front Neurosci 2023; 16:1013673. [PMID: 36699530 PMCID: PMC9868941 DOI: 10.3389/fnins.2022.1013673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 11/30/2022] [Indexed: 01/27/2023] Open
Abstract
Introduction Understanding how environmental interact challenges with genetic predispositions modulate health and wellbeing is an important area of biomedical research. Circadian rhythms play an important role in coordinating the multitude of cellular and tissue processes that organisms use to predict and adapt to regular changes in the environment, and robust circadian rhythms contribute to optimal physiological and behavioral responses to challenge. However, artificial lighting and modern round-the-clock lifestyles can disrupt the circadian system, leading to desynchronization of clocks throughout the brain and body. When coupled with genetic predispositions, circadian desynchronization may compound negative outcomes. Polymorphisms in the brain-derived neurotrophic (BDNF) gene contribute to variations in neurobehavioral responses in humans, including impacts on sleep, with the common Val66Met polymorphism linked to several negative outcomes. Methods We explored how the Val66Met polymorphism modulates the response to environmental circadian desynchronization (ECD) in a mouse model. ECD was induced by housing adult male mice in a 20 h light-dark cycle (LD10:10; 10 h light, 10 h dark). Sleep and circadian activity were recorded in homozygous (Met) mice and their wild-type (Val) littermates in a standard 24 h LD cycle (LD12:12), then again after 20, 40, and 60 days of ECD. Results We found ECD significantly affected the sleep/wake timing in Val mice, however, Met mice maintained appropriate sleep timing after 20 days ECD, but not after 40 and 60 days of ECD. In addition, the rise in delta power at lights on was absent in Val mice but was maintained in Met mice. To elucidate the circadian and homeostatic contribution to disrupted sleep, mice were sleep deprived by gentle handling in LD12:12 and after 20 days in ECD. Following 6 h of sleep deprivation delta power was increased for both Val and Met mice in LD12:12 and ECD conditions. However, the time constant was significantly longer in the Val mice during ECD compared to LD12:12, suggesting a functioning but altered sleep homeostat. Discussion These data suggest the Val66Met mutation is associated with an ability to resist the effects of LD10:10, which may result in carriers suffering fewer negative impacts of ECD.
Collapse
Affiliation(s)
- Derrick J. Phillips
- WWAMI Medical Education Program, University of Idaho, Moscow, ID, United States,*Correspondence: Derrick J. Phillips,
| | - Scott Blaine
- Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, WA, United States
| | - Naomi K. Wallace
- Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, WA, United States
| | - Ilia N. Karatsoreos
- Neuroscience and Behavior Program, Department of Psychological and Brain Sciences, University of Massachusetts Amherst, Amherst, MA, United States,Ilia N. Karatsoreos,
| |
Collapse
|
35
|
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 PMCID: PMC11318661 DOI: 10.1126/sciadv.abq7032] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [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
|
36
|
Zheng Y, Pan L, Wang F, Yan J, Wang T, Xia Y, Yao L, Deng K, Zheng Y, Xia X, Su Z, Chen H, Lin J, Ding Z, Zhang K, Zhang M, Chen Y. Neural function of Bmal1: an overview. Cell Biosci 2023; 13:1. [PMID: 36593479 PMCID: PMC9806909 DOI: 10.1186/s13578-022-00947-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 12/19/2022] [Indexed: 01/04/2023] Open
Abstract
Bmal1 (Brain and muscle arnt-like, or Arntl) is a bHLH/PAS domain transcription factor central to the transcription/translation feedback loop of the biologic clock. Although Bmal1 is well-established as a major regulator of circadian rhythm, a growing number of studies in recent years have shown that dysfunction of Bmal1 underlies a variety of psychiatric, neurodegenerative-like, and endocrine metabolism-related disorders, as well as potential oncogenic roles. In this review, we systematically summarized Bmal1 expression in different brain regions, its neurological functions related or not to circadian rhythm and biological clock, and pathological phenotypes arising from Bmal1 knockout. This review also discusses oscillation and rhythmicity, especially in the suprachiasmatic nucleus, and provides perspective on future progress in Bmal1 research.
Collapse
Affiliation(s)
- Yuanjia Zheng
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China ,grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lingyun Pan
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Feixue Wang
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Jinglan Yan
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Taiyi Wang
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Yucen Xia
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Lin Yao
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Kelin Deng
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yuqi Zheng
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiaoye Xia
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhikai Su
- grid.411866.c0000 0000 8848 7685The Second Clinical College, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong China
| | - Hongjie Chen
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jie Lin
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhenwei Ding
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Kaitong Zhang
- grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Meng Zhang
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Yongjun Chen
- grid.464402.00000 0000 9459 9325Research Institute of Acupuncture and Moxibustion, Shandong University of Traditional Chinese Medicine, Jinan, China ,grid.411866.c0000 0000 8848 7685South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China ,Center for Brain Science and Brain-Inspired Intelligence, Guangdong-Hong Kong-Macao Greater Bay Area, Guangzhou, China
| |
Collapse
|
37
|
Abstract
Our physiology and behavior follow precise daily programs that adapt us to the alternating opportunities and challenges of day and night. Under experimental isolation, these rhythms persist with a period of approximately one day (circadian), demonstrating their control by an internal autonomous clock. Circadian time is created at the cellular level by a transcriptional/translational feedback loop (TTFL) in which the protein products of the Period and Cryptochrome genes inhibit their own transcription. Because the accumulation of protein is slow and delayed, the system oscillates spontaneously with a period of ∼24 hours. This cell-autonomous TTFL controls cycles of gene expression in all major tissues and these cycles underpin our daily metabolic programs. In turn, our innumerable cellular clocks are coordinated by a central pacemaker, the suprachiasmatic nucleus (SCN) of the hypothalamus. When isolated in slice culture, the SCN TTFL and its dependent cycles of neural activity persist indefinitely, operating as "a clock in a dish". In vivo, SCN time is synchronized to solar time by direct innervation from specialized retinal photoreceptors. In turn, the precise circadian cycle of action potential firing signals SCN-generated time to hypothalamic and brain stem targets, which co-ordinate downstream autonomic, endocrine, and behavioral (feeding) cues to synchronize and sustain the distributed cellular clock network. Circadian time therefore pervades every level of biological organization, from molecules to society. Understanding its mechanisms offers important opportunities to mitigate the consequences of circadian disruption, so prevalent in modern societies, that arise from shiftwork, aging, and neurodegenerative diseases, not least Huntington's disease.
Collapse
Affiliation(s)
- Andrew P. Patton
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | |
Collapse
|
38
|
Psarellis YM, Kavousanakis M, Henson MA, Kevrekidis IG. Limits of entrainment of circadian neuronal networks. CHAOS (WOODBURY, N.Y.) 2023; 33:013137. [PMID: 36725649 PMCID: PMC9883082 DOI: 10.1063/5.0122744] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 12/19/2022] [Indexed: 06/07/2023]
Abstract
Circadian rhythmicity lies at the center of various important physiological and behavioral processes in mammals, such as sleep, metabolism, homeostasis, mood changes, and more. Misalignment of intrinsic neuronal oscillations with the external day-night cycle can disrupt such processes and lead to numerous disorders. In this work, we computationally determine the limits of circadian synchronization to external light signals of different frequency, duty cycle, and simulated amplitude. Instead of modeling circadian dynamics with generic oscillator models (e.g., Kuramoto-type), we use a detailed computational neuroscience model, which integrates biomolecular dynamics, neuronal electrophysiology, and network effects. This allows us to investigate the effect of small drug molecules, such as Longdaysin, and connect our results with experimental findings. To combat the high dimensionality of such a detailed model, we employ a matrix-free approach, while our entire algorithmic pipeline enables numerical continuation and construction of bifurcation diagrams using only direct simulation. We, thus, computationally explore the effect of heterogeneity in the circadian neuronal network, as well as the effect of the corrective therapeutic intervention of Longdaysin. Last, we employ unsupervised learning to construct a data-driven embedding space for representing neuronal heterogeneity.
Collapse
Affiliation(s)
- Yorgos M. Psarellis
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Michail Kavousanakis
- School of Chemical Engineering, National Technical University of Athens, Zografou, Athens 15780, Greece
| | - Michael A. Henson
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
| | | |
Collapse
|
39
|
Han K, Huang Y. Microfluidic Approach for Modeling Coupled Circadian Clock. Methods Mol Biol 2023; 2689:107-118. [PMID: 37430050 DOI: 10.1007/978-1-0716-3323-6_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
In mammals, it is believed that the intercellular coupling mechanism between neurons in the suprachiasmatic nucleus (SCN) confers circadian robustness and distinguishes the central clock from peripheral circadian oscillators. Current in vitro culturing methods mainly work with Petri dishes to study intercellular coupling by exogenous factors and invariably cause perturbations, such as simple exchanges of media. Here, a microfluidic device is designed to quantitatively study the intercellular coupling mechanism of circadian clock at the single-cell level and to demonstrate that the vasoactive intestinal peptide (VIP)-induced coupling in clock mutant Cry1-/- mouse adult fibroblasts (MAF), which are engineered to express the VIP receptor (i.e., VPAC2), is sufficient to synchronize, and maintain, robust circadian oscillations. This method provides a proof-of-concept strategy to reconstitute the intercellular coupling system of the central clock using uncoupled, single mouse adult fibroblast (MAF) cells in vitro and to mimic SCN slice cultures ex vivo and mouse behavior in vivo phenotypically. Such a versatile microfluidic platform may greatly facilitate the studies of intercellular regulation networks and provide new insights into the coupling mechanisms of the circadian clock.
Collapse
Affiliation(s)
- Kui Han
- Changping Laboratory, Beijing, China
| | - Yanyi Huang
- Biomedical Pioneering Innovation Center (BIOPIC), College of Chemistry, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.
| |
Collapse
|
40
|
Skipping breakfast regimen induces an increase in body weight and a decrease in muscle weight with a shifted circadian rhythm in peripheral tissues of mice. Br J Nutr 2022; 128:2308-2319. [PMID: 35272720 DOI: 10.1017/s0007114522000356] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Meal timing is a key factor in synchronising the circadian clock in peripheral tissues. Circadian disorders are associated with the metabolic syndrome. Previously, we demonstrated that a skipping breakfast regimen (SBR) with a high-fat diet increased body weight gain in rats. In this study, we investigated whether SBR with a normal diet led to abnormal lipid metabolism and muscle metabolism in mice. Male C57BL/6 mice were fed during zeitgeber time (ZT) 12-24 in the control group and ZT 16-24 in the SBR group for 2 weeks. SBR mice showed increased body weight gain and perirenal adipose tissue weight. The plantar muscle weight was decreased in the SBR group compared with that in the control group. Furthermore, SBR delayed the circadian oscillations in clock gene expression in peripheral tissues, such as the liver, adipose tissue and muscle, as well as the oscillations in the expression of lipid metabolism-related genes in the liver and adipose tissue. These results suggest that skipping breakfast over a long period of time is associated with a risk of obesity, the metabolic syndrome and muscle loss, such as sarcopenia.
Collapse
|
41
|
Rojo D, Badner A, Gibson EM. Circadian Control of Glial Cell Homeodynamics. J Biol Rhythms 2022; 37:593-608. [PMID: 36068711 PMCID: PMC9729367 DOI: 10.1177/07487304221120966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The molecular mechanisms that maintain circadian rhythms in mammalian as well as non-mammalian systems are well documented in neuronal populations but comparatively understudied in glia. Glia are highly dynamic in form and function, and the circadian clock provides broad dynamic ranges for the maintenance of this homeostasis, thus glia are key to understanding the role of circadian biology in brain function. Here, we highlight the implications of the molecular circadian clock on the homeodynamic nature of glia, underscoring the current gap in understanding the role of the circadian system in oligodendroglia lineage cells and subsequent myelination. Through this perspective, we will focus on the intersection of circadian and glial biology and how it interfaces with global circadian rhythm maintenance associated with normative and aberrant brain function.
Collapse
Affiliation(s)
- Daniela Rojo
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Anna Badner
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Erin M. Gibson
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Palo Alto, CA 94305, USA,Corresponding Author: Erin M. Gibson, PhD, 3165 Porter Drive, #2178, Palo Alto, CA 94304, (650)725-6659,
| |
Collapse
|
42
|
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
|
43
|
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
|
44
|
Auerbach BJ, FitzGerald GA, Li M. Tempo: an unsupervised Bayesian algorithm for circadian phase inference in single-cell transcriptomics. Nat Commun 2022; 13:6580. [PMID: 36323668 PMCID: PMC9630322 DOI: 10.1038/s41467-022-34185-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022] Open
Abstract
The circadian clock is a 24 h cellular timekeeping mechanism that regulates human physiology. Answering several fundamental questions in circadian biology will require joint measures of single-cell circadian phases and transcriptomes. However, no widespread experimental approaches exist for this purpose. While computational approaches exist to infer cell phase directly from single-cell RNA-sequencing data, existing methods yield poor circadian phase estimates, and do not quantify estimation uncertainty, which is essential for interpretation of results from very sparse single-cell RNA-sequencing data. To address these unmet needs, we introduce Tempo, a Bayesian variational inference approach that incorporates domain knowledge of the clock and quantifies phase estimation uncertainty. Through simulations and analyses of real data, we demonstrate that Tempo yields more accurate estimates of circadian phase than existing methods and provides well-calibrated uncertainty quantifications. Tempo will facilitate large-scale studies of single-cell circadian transcription.
Collapse
Affiliation(s)
- Benjamin J Auerbach
- Graduate Group in Genomics and Computational Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA.
| | - Garret A FitzGerald
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA
| | - Mingyao Li
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA.
| |
Collapse
|
45
|
van Beurden AW, Schoonderwoerd RA, Tersteeg MMH, de Torres Gutiérrez P, Michel S, Blommers R, Rohling JHT, Meijer JH. Single cell model for re-entrainment to a shifted light cycle. FASEB J 2022; 36:e22518. [PMID: 36057093 PMCID: PMC9543151 DOI: 10.1096/fj.202200478r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 07/25/2022] [Accepted: 08/15/2022] [Indexed: 11/11/2022]
Abstract
Our daily 24-h rhythm is synchronized to the external light-dark cycle resulting from the Earth's daily rotation. In the mammalian brain, the suprachiasmatic nucleus (SCN) serves as the master clock and receives light-mediated input via the retinohypothalamic tract. Abrupt changes in the timing of the light-dark cycle (e.g., due to jet lag) cause a phase shift in the circadian rhythms in the SCN. Here, we investigated the effects of a 6-h delay in the light-dark cycle on PERIOD2::LUCIFERASE expression at the single-cell level in mouse SCN organotypic explants. The ensemble pattern in phase shift response obtained from individual neurons in the anterior and central SCN revealed a bimodal distribution; specifically, neurons in the ventrolateral SCN responded with a rapid phase shift, while neurons in the dorsal SCN generally did not respond to the shift in the light-dark cycle. We also stimulated the hypothalamic tract in acute SCN slices to simulate light-mediated input to the SCN; interestingly, we found similarities between the distribution and fraction of rapid shifting neurons (in response to the delay) and neurons that were excited in response to electrical stimulation. These results suggest that a subpopulation of neurons in the ventral SCN that have an excitatory response to light input, shift their clock more readily than dorsal located neurons, and initiate the SCN's entrainment to the new light-dark cycle. Thus, we propose that light-excited neurons in the anterior and central SCN play an important role in the organism's ability to adjust to changes in the external light-dark cycle.
Collapse
Affiliation(s)
- Anouk W van Beurden
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Robin A Schoonderwoerd
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Mayke M H Tersteeg
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Stephan Michel
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Ruben Blommers
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jos H T Rohling
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Johanna H Meijer
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
46
|
Abdalla OHMH, Mascarenhas B, Cheng HYM. Death of a Protein: The Role of E3 Ubiquitin Ligases in Circadian Rhythms of Mice and Flies. Int J Mol Sci 2022; 23:ijms231810569. [PMID: 36142478 PMCID: PMC9502492 DOI: 10.3390/ijms231810569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 12/04/2022] Open
Abstract
Circadian clocks evolved to enable organisms to anticipate and prepare for periodic environmental changes driven by the day–night cycle. This internal timekeeping mechanism is built on autoregulatory transcription–translation feedback loops that control the rhythmic expression of core clock genes and their protein products. The levels of clock proteins rise and ebb throughout a 24-h period through their rhythmic synthesis and destruction. In the ubiquitin–proteasome system, the process of polyubiquitination, or the covalent attachment of a ubiquitin chain, marks a protein for degradation by the 26S proteasome. The process is regulated by E3 ubiquitin ligases, which recognize specific substrates for ubiquitination. In this review, we summarize the roles that known E3 ubiquitin ligases play in the circadian clocks of two popular model organisms: mice and fruit flies. We also discuss emerging evidence that implicates the N-degron pathway, an alternative proteolytic system, in the regulation of circadian rhythms. We conclude the review with our perspectives on the potential for the proteolytic and non-proteolytic functions of E3 ubiquitin ligases within the circadian clock system.
Collapse
Affiliation(s)
- Osama Hasan Mustafa Hasan Abdalla
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Brittany Mascarenhas
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Hai-Ying Mary Cheng
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
- Correspondence:
| |
Collapse
|
47
|
Tang M, Cao LH, Yang T, Ma SX, Jing BY, Xiao N, Xu S, Leng KR, Yang D, Li MT, Luo DG. An extra-clock ultradian brain oscillator sustains circadian timekeeping. SCIENCE ADVANCES 2022; 8:eabo5506. [PMID: 36054358 PMCID: PMC10848952 DOI: 10.1126/sciadv.abo5506] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
The master circadian clock generates 24-hour rhythms to orchestrate daily behavior, even running freely under constant conditions. Traditionally, the master clock is considered self-sufficient in sustaining free-running timekeeping via its cell-autonomous molecular clocks and interneuronal communications within the circadian neural network. Here, we find a set of bona fide ultradian oscillators in the Drosophila brain that support free-running timekeeping, despite being located outside the master clock circuit and lacking clock gene expression. These extra-clock electrical oscillators (xCEOs) generate cell-autonomous ultradian bursts, pacing widespread burst firing and promoting rhythmic resting membrane potentials in clock neurons via parallel monosynaptic connections. Silencing xCEOs disrupts daily electrical rhythms in clock neurons and impairs cycling of neuropeptide pigment dispersing factor, leading to the loss of free-running locomotor rhythms. Together, we conclude that the master clock is not self-sufficient to sustain free-running behavior rhythms but requires additional endogenous inputs to the clock from the extra-clock ultradian brain oscillators.
Collapse
Affiliation(s)
- Min Tang
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
- PTN Graduate Program, School of Life Sciences, Peking University, Beijing 100871, China
| | - Li-Hui Cao
- School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Capital Medical University, Beijing 100069, China
| | - Tian Yang
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Si-Xing Ma
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Bi-Yang Jing
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Na Xiao
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Shuang Xu
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Kang-Rui Leng
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Dong Yang
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Meng-Tong Li
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Dong-Gen Luo
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
- IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| |
Collapse
|
48
|
Singla R, Mishra A, Cao R. The trilateral interactions between mammalian target of rapamycin (mTOR) signaling, the circadian clock, and psychiatric disorders: an emerging model. Transl Psychiatry 2022; 12:355. [PMID: 36045116 PMCID: PMC9433414 DOI: 10.1038/s41398-022-02120-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 08/08/2022] [Accepted: 08/12/2022] [Indexed: 02/07/2023] Open
Abstract
Circadian (~24 h) rhythms in physiology and behavior are evolutionarily conserved and found in almost all living organisms. The rhythms are endogenously driven by daily oscillatory activities of so-called "clock genes/proteins", which are widely distributed throughout the mammalian brain. Mammalian (mechanistic) target of rapamycin (mTOR) signaling is a fundamental intracellular signal transduction cascade that controls important neuronal processes including neurodevelopment, synaptic plasticity, metabolism, and aging. Dysregulation of the mTOR pathway is associated with psychiatric disorders including autism spectrum disorders (ASD) and mood disorders (MD), in which patients often exhibit disrupted daily physiological rhythms and abnormal circadian gene expression in the brain. Recent work has found that the activities of mTOR signaling are temporally controlled by the circadian clock and exhibit robust circadian oscillations in multiple systems. In the meantime, mTOR signaling regulates fundamental properties of the central and peripheral circadian clocks, including period length, entrainment, and synchronization. Whereas the underlying mechanisms remain to be fully elucidated, increasing clinical and preclinical evidence support significant crosstalk between mTOR signaling, the circadian clock, and psychiatric disorders. Here, we review recent progress in understanding the trilateral interactions and propose an "interaction triangle" model between mTOR signaling, the circadian clock, and psychiatric disorders (focusing on ASD and MD).
Collapse
Affiliation(s)
- Rubal Singla
- grid.17635.360000000419368657Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812 USA
| | - Abhishek Mishra
- grid.17635.360000000419368657Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812 USA
| | - Ruifeng Cao
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, 55812, USA. .,Department of Neuroscience, University of Minnesota Medical School, Minneapolis, MN, 55455, USA.
| |
Collapse
|
49
|
Goltsev AV, Wright EAP, Mendes JFF, Yoon S. Generation and Disruption of Circadian Rhythms in the Suprachiasmatic Nucleus: A Core-Shell Model. J Biol Rhythms 2022; 37:545-561. [PMID: 35848398 PMCID: PMC9452856 DOI: 10.1177/07487304221107834] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We focus our research on how the core-shell organization controls behavior of the
suprachiasmatic nucleus (SCN), how the core and shell are synchronized to the
environment, what impact they have on the behavior of the SCN under different
lighting conditions, and what mechanisms disrupt synchronization. To this end,
we use a reduced Kuramoto model, with parameters inferred from experimental
observations and calibrated for mice, and perform a detailed comparison between
the model and experimental data under light-dark (LD), dark-dark (DD), and
light-light (LL) conditions. The operating limits of free-running and entrained
SCN activity under symmetric LD cycles are analyzed, with particular focus on
the phenomena of anticipation and dissociation. Results reveal that the
core-shell organization of the SCN enables anticipation of future events over
circadian cycles. The model predicts the emergence of a second (dissociated)
rhythm for large and small LD periods. Our results are in good qualitative and
quantitative agreement with experimental observations of circadian dissociation.
We further describe SCN activity under LL conditions and show that our model
satisfies Aschoff’s first rule, according to which the endogenous free-running
circadian period observed under complete darkness will shorten in diurnal
animals and lengthen in nocturnal animals under constant light. Our results
strongly suggest that the Kuramoto model captures essential features of
synchronization and entrainment in the SCN. Moreover, our approach is easily
extendible to an arbitrary number of groups, with dynamics described by explicit
equations for the group phase and synchronization index. Viewed together, the
reduced Kuramoto model presents itself as a useful tool for exploring open
problems in the study of circadian rhythms, one that can account for evolving
views of the circadian system’s organization, including peripheral clocks and
inter-hemispheric interaction, and can be translated to other nocturnal and
diurnal animals, including humans.
Collapse
Affiliation(s)
| | - Edgar A P Wright
- Department of Physics & I3N, University of Aveiro, Aveiro, Portugal
| | - José F F Mendes
- Department of Physics & I3N, University of Aveiro, Aveiro, Portugal
| | - Sooyeon Yoon
- Department of Physics & I3N, University of Aveiro, Aveiro, Portugal
| |
Collapse
|
50
|
Yamaguchi T, Hamada T, Iijima N. Differences in recovery processes of circadian oscillators in various tissues after sevoflurane treatment in vivo. Biochem Biophys Rep 2022; 30:101258. [PMID: 35434385 PMCID: PMC9006766 DOI: 10.1016/j.bbrep.2022.101258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/23/2022] [Accepted: 04/01/2022] [Indexed: 11/30/2022] Open
Abstract
The inhalation anesthetic sevoflurane reversibly suppresses Period2 (Per2) mRNA expression in the suprachiasmatic nucleus (SCN). However, a discrepancy exists in phase shifting of the Per2 expression rhythm between sevoflurane application in rats (in vivo application) and explants (ex vivo application). This investigation aimed to resolve this issue. First, tissues from the SCN, choroid plexus in the lateral ventricle (CP-LV), and choroid plexus in the fourth ventricle (CP–4V), which are robust circadian oscillators, and pineal gland (PG) tissue, which is a circadian influencer, were prepared from Per2::dLuc transgenic rats. Significant phase responses of bioluminescence rhythms for different preparation times were monitored in the four tissue explant types. Second, tissue explants were prepared from anesthetized rats immediately after sevoflurane treatment, and bioluminescence rhythms were compared with those from non-anesthetized rats at various preparation times. Regarding bioluminescence rhythm phases, in vivo application of sevoflurane induced phase shifts in CP-LV, CP-4V, and PG explants according to the times that rats were administered anesthesia and the explants were prepared. Phase shifts in these peripheral explants were withdrawn due to the recovery period after the anesthetic treatment, which suggests that peripheral tissues require the assistance of related tissues or organs to correct phase shifts. In contrast, no phase shifts were observed in SCN explants. These results indicated that SCN explants can independently correct bioluminescence rhythm phase. The bioluminescence intensity of explants was also decreased after in vivo sevoflurane application. The suppressive effects on SCN explants were withdrawn due to a recovery day after the anesthetic treatment. In contrast, the suppressive effects on the bioluminescence intensities of CP-LV, CP-4V, and PG explants remained at 30 days after anesthesia administration. These results suggest that anesthetic suppression is imprinted within the peripheral tissues. We monitored bioluminescence in explants from Per2::dLuc rats after anesthesia. Sevoflurane induced phase shifts in peripheral explants but not in the SCN. Phase shifts in peripheral explants were withdrawn due to recovery period. Sevoflurane weakened the bioluminescence intensity of all explant types. The suppressive effects on peripheral explants were remained in a week later.
Collapse
Affiliation(s)
- Takeshi Yamaguchi
- Center for Basic Medical Research, International University of Health and Welfare, Ohtawara, Tochigi, Japan
| | - Toshiyuki Hamada
- Department of Pharmacology, 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
- Corresponding author.
| |
Collapse
|