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Bonilla P, Shanks A, Nerella Y, Porcu A. Effects of chronic light cycle disruption during adolescence on circadian clock, neuronal activity rhythms, and behavior in mice. Front Neurosci 2024; 18:1418694. [PMID: 38952923 PMCID: PMC11215055 DOI: 10.3389/fnins.2024.1418694] [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: 04/16/2024] [Accepted: 05/29/2024] [Indexed: 07/03/2024] Open
Abstract
The advent of artificial lighting, particularly during the evening and night, has significantly altered the predictable daily light and dark cycles in recent times. Altered light environments disrupt the biological clock and negatively impact mood and cognition. Although adolescents commonly experience chronic changes in light/dark cycles, our understanding of how the adolescents' brain adapts to altered light environments remains limited. Here, we investigated the impact of chronic light cycle disruption (LCD) during adolescence, exposing adolescent mice to 19 h of light and 5 h of darkness for 5 days and 12 L:12D for 2 days per week (LCD group) for 4 weeks. We showed that LCD exposure did not affect circadian locomotor activity but impaired memory and increased avoidance response in adolescent mice. Clock gene expression and neuronal activity rhythms analysis revealed that LCD disrupted local molecular clock and neuronal activity in the dentate gyrus (DG) and in the medial amygdala (MeA) but not in the circadian pacemaker (SCN). In addition, we characterized the photoresponsiveness of the MeA and showed that somatostatin neurons are affected by acute and chronic aberrant light exposure during adolescence. Our research provides new evidence highlighting the potential consequences of altered light environments during pubertal development on neuronal physiology and behaviors.
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Affiliation(s)
| | | | | | - Alessandra Porcu
- Department of Drug Discovery and Biomedical Science, University of South Carolina, Columbia, SC, United States
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2
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Naveed M, Chao OY, Hill JW, Yang YM, Huston JP, Cao R. Circadian neurogenetics and its implications in neurophysiology, behavior, and chronomedicine. Neurosci Biobehav Rev 2024; 157:105523. [PMID: 38142983 PMCID: PMC10872425 DOI: 10.1016/j.neubiorev.2023.105523] [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: 09/05/2023] [Revised: 12/13/2023] [Accepted: 12/20/2023] [Indexed: 12/26/2023]
Abstract
The circadian rhythm affects multiple physiological processes, and disruption of the circadian system can be involved in a range of disease-related pathways. The genetic underpinnings of the circadian rhythm have been well-studied in model organisms. Significant progress has been made in understanding how clock genes affect the physiological functions of the nervous system. In addition, circadian timing is becoming a key factor in improving drug efficacy and reducing drug toxicity. The circadian biology of the target cell determines how the organ responds to the drug at a specific time of day, thus regulating pharmacodynamics. The current review brings together recent advances that have begun to unravel the molecular mechanisms of how the circadian clock affects neurophysiological and behavioral processes associated with human brain diseases. We start with a brief description of how the ubiquitous circadian rhythms are regulated at the genetic, cellular, and neural circuit levels, based on knowledge derived from extensive research on model organisms. We then summarize the latest findings from genetic studies of human brain disorders, focusing on the role of human clock gene variants in these diseases. Lastly, we discuss the impact of common dietary factors and medications on human circadian rhythms and advocate for a broader application of the concept of chronomedicine.
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Affiliation(s)
- Muhammad Naveed
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA; Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH 43614, USA
| | - Owen Y Chao
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
| | - Jennifer W Hill
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH 43614, USA
| | - Yi-Mei Yang
- 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
| | - Joseph P Huston
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Ruifeng Cao
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA; Department of Neurology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA.
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3
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Boyd HM, Frick KM, Kwapis JL. Connecting the Dots: Potential Interactions Between Sex Hormones and the Circadian System During Memory Consolidation. J Biol Rhythms 2023; 38:537-555. [PMID: 37464775 PMCID: PMC10615791 DOI: 10.1177/07487304231184761] [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: 07/20/2023]
Abstract
Both the circadian clock and sex hormone signaling can strongly influence brain function, yet little is known about how these 2 powerful modulatory systems might interact during complex neural processes like memory consolidation. Individually, the molecular components and action of each of these systems have been fairly well-characterized, but there is a fundamental lack of information about how these systems cooperate. In the circadian system, clock genes function as timekeeping molecules that convey time-of-day information on a well-stereotyped cycle that is governed by the suprachiasmatic nucleus. Keeping time is particularly important to synchronize various physiological processes across the brain and body, including those that regulate memory consolidation. Similarly, sex hormones are powerful modulators of memory, with androgens, estrogens, and progestins, all influencing memory consolidation within memory-relevant brain regions like the hippocampus. Despite clear evidence that each system can influence memory individually, exactly how the circadian and hormonal systems might interact to impact memory consolidation remains unclear. Research investigating either sex hormone action or circadian gene function within memory-relevant brain regions has unveiled several notable places in which the two systems could interact to control memory. Here, we bring attention to known interactions between the circadian clock and sex hormone signaling. We then review sex hormone-mediated control of memory consolidation, highlighting potential nodes through which the circadian system might interact during memory formation. We suggest that the bidirectional relationship between these two systems is essential for proper control of memory formation based on an animal's hormonal and circadian state.
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Affiliation(s)
- Hannah M. Boyd
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, Pennsylvania
| | - Karyn M. Frick
- Department of Psychology, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin
| | - Janine L. Kwapis
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania
- Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, Pennsylvania
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Chbeir S, Carrión V. Resilience by design: How nature, nurture, environment, and microbiome mitigate stress and allostatic load. World J Psychiatry 2023; 13:144-159. [PMID: 37303926 PMCID: PMC10251360 DOI: 10.5498/wjp.v13.i5.144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 02/11/2023] [Accepted: 04/17/2023] [Indexed: 05/19/2023] Open
Abstract
Resilience to psychological stress is defined as adaption to challenging life experiences and not the absence of adverse life events. Determinants of resilience include personality traits, genetic/epigenetic modifications of genes involved in the stress response, cognitive and behavioral flexibility, secure attachment with a caregiver, social and community support systems, nutrition and exercise, and alignment of circadian rhythm to the natural light/dark cycle. Therefore, resilience is a dynamic and flexible process that continually evolves by the intersection of different domains in human’s life; biological, social, and psychological. The objective of this minireview is to summarize the existing knowledge about the multitude factors and molecular alterations that result from resilience to stress response. Given the multiple contributing factors in building resilience, we set out a goal to identify which factors were most supportive of a causal role by the current literature. We focused on resilience-related molecular alterations resulting from mind-body homeostasis in connection with psychosocial and environmental factors. We conclude that there is no one causal factor that differentiates a resilient person from a vulnerable one. Instead, building resilience requires an intricate network of positive experiences and a healthy lifestyle that contribute to a balanced mind-body connection. Therefore, a holistic approach must be adopted in future research on stress response to address the multiple elements that promote resilience and prevent illnesses and psychopathology related to stress allostatic load.
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Affiliation(s)
- Souhad Chbeir
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, Stanford, CA 94305, United States
| | - Victor Carrión
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, Stanford, CA 94305, United States
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5
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Meng D, Yang M, Zhang H, Zhang L, Song H, Liu Y, Zeng Y, Yang B, Wang X, Chen Y, Liu R. Microglia activation mediates circadian rhythm disruption-induced cognitive impairment in mice. J Neuroimmunol 2023; 379:578102. [PMID: 37196595 DOI: 10.1016/j.jneuroim.2023.578102] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 04/18/2023] [Accepted: 05/03/2023] [Indexed: 05/19/2023]
Abstract
Alzheimer's disease (AD) is the leading cause of dementia and there are no effective treatments for this disease currently. Circadian rhythm disruption (CRD) is a hallmark of modern society that appears to be on the rise. It is well reported that AD is associated with disrupted circadian functioning and CRD can impair cognitive function. However, the cellular mechanisms underlying CRD-associated cognitive decline remain elusive. In this study, we investigated whether microglia are involved in CRD-induced cognitive decline. We established experimental 'jet lag' (phase delay of the light/dark cycles)-induced CRD mouse model and observed significant impairment of spatial learning and memory function in these mice. In the brain, CRD resulted in neuroinflammation, which was characterized by microglia activation and increased pro-inflammatory cytokine production, impairments in neurogenesis and reduction of synaptic proteins in the hippocampus. Interestingly, elimination of microglia with the colony stimulating factor-1 receptor inhibitor PLX3397 prevented CRD-induced neuroinflammation, cognitive decline, impairment of neurogenesis and loss of synaptic proteins. These findings collectively suggest that microglia activation plays a key role in CRD-induced cognitive deficit most likely through neuroinflammation-mediated impairments in adult neurogenesis and synapses.
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Affiliation(s)
- Dongli Meng
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Mengzhe Yang
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Huiliang Zhang
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lun Zhang
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Haiyue Song
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yi Liu
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yi Zeng
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Clinical Laboratory, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bo Yang
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Clinical Laboratory, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaochuan Wang
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yu Chen
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Rong Liu
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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6
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Schurhoff N, Toborek M. Circadian rhythms in the blood-brain barrier: impact on neurological disorders and stress responses. Mol Brain 2023; 16:5. [PMID: 36635730 PMCID: PMC9835375 DOI: 10.1186/s13041-023-00997-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 01/03/2023] [Indexed: 01/14/2023] Open
Abstract
Circadian disruption has become more prevalent in society due to the increase in shift work, sleep disruption, blue light exposure, and travel via different time zones. The circadian rhythm is a timed transcription-translation feedback loop with positive regulators, BMAL1 and CLOCK, that interact with negative regulators, CRY and PER, to regulate both the central and peripheral clocks. This review highlights the functions of the circadian rhythm, specifically in the blood-brain barrier (BBB), during both healthy and pathological states. The BBB is a highly selective dynamic interface composed of CNS endothelial cells, astrocytes, pericytes, neurons, and microglia that form the neurovascular unit (NVU). Circadian rhythms modulate BBB integrity through regulating oscillations of tight junction proteins, assisting in functions of the NVU, and modulating transporter functions. Circadian disruptions within the BBB have been observed in stress responses and several neurological disorders, including brain metastasis, epilepsy, Alzheimer's disease, and Parkinson's disease. Further understanding of these interactions may facilitate the development of improved treatment options and preventative measures.
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Affiliation(s)
- Nicolette Schurhoff
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Suite 528, 1011 NW 15th Street, Miami, FL, 33155, USA
| | - Michal Toborek
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Suite 528, 1011 NW 15th Street, Miami, FL, 33155, USA.
- Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, 40-065, Katowice, Poland.
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7
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Banks G, Nolan PM, Bourbia N. Shift work-like patterns effect on female and male mouse behavior. Neurobiol Sleep Circadian Rhythms 2022; 13:100082. [PMID: 36267148 PMCID: PMC9576555 DOI: 10.1016/j.nbscr.2022.100082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 09/15/2022] [Accepted: 10/07/2022] [Indexed: 10/31/2022] Open
Abstract
Shift work (work outside of standard daylight hours) is common throughout the Western world. However, there are notable health consequences to shift work, including increased prevalence of mental health and sleep disorders in shift worker populations. Therefore, the health and wellbeing of shift workers is a public health concern that needs to be addressed. Here we investigate the effects of two separate light induced shift work-like patterns on male and female mouse behaviour (anxiety-like, exploration, marble burying, startle reflex and circadian rhythms). After 6 weeks of shift-like disruptions patterns, animals displayed no behavioral differences in exploration, marble burying and startle reflex. Interestingly however, we identified sex specific and disruption specific effects in light aversion and wheel running activities. Notably, analysis of the activity patterns of animals in disruptive conditions demonstrated that they maintained a degree of rhythmicity through the disruption period, which may explain the lack of behavioral differences in most behavioral tests.
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Affiliation(s)
- Gareth Banks
- MRC Harwell Institute, Harwell Science and Innovation Campus, Harwell, Oxfordshire, OX11 0RD, UK
| | - Patrick M. Nolan
- MRC Harwell Institute, Harwell Science and Innovation Campus, Harwell, Oxfordshire, OX11 0RD, UK
| | - Nora Bourbia
- MRC Harwell Institute, Harwell Science and Innovation Campus, Harwell, Oxfordshire, OX11 0RD, UK
- UK Health Security Agency, Harwell Campus, Chilton, Didcot, OX11 0RQ, UK
- Corresponding author. UK Health Security Agency, Harwell Campus, Chilton, Didcot, OX11 0RD, UK.
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8
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Deibel SH, Higdon S, Cassell TTS, House-Denine ML, Giberson E, Webb IC, Thorpe CM. Impaired Morris water task retention following T21 light dark cycle exposure is not due to reduced hippocampal c-FOS expression. Front Behav Neurosci 2022; 16:1025388. [PMID: 36311860 PMCID: PMC9596763 DOI: 10.3389/fnbeh.2022.1025388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 09/09/2022] [Indexed: 11/21/2022] Open
Abstract
Circadian rhythms influence virtually all aspects of physiology and behavior. This is problematic when circadian rhythms no longer reliably predict time. Circadian rhythm disruption can impair memory, yet we don’t know how this fully works at the systems and molecular level. When trying to determine the root of a memory impairment, assessing neuronal activation with c-FOS is useful. This has yet to be assessed in the hippocampi of circadian rhythm disrupted rats in a hippocampal gold standard task. Rats were trained on the Morris water task (MWT), then received 6 days of a 21-h day (T21), 13 days of a normal light dark cycle, probe trial, and tissue extraction an hour later. Despite having impaired memory in the probe trial, compared to controls there were no differences in c-FOS expression in hippocampal sub regions: CA1; CA3; Dentate gyrus. These data confirm others in hamsters demonstrating that arrhythmicity which produces an impairment in spontaneous alternation does not affect c-FOS in the dentate gyrus. The current study indicates that the memory impairment induced by a lighting manipulation is likely not due to attenuated neuronal activation. Determining how the master clock in the brain communicates with the hippocampus is needed to untangle the relationship between circadian rhythms and memory.
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Affiliation(s)
- Scott H. Deibel
- Department of Psychology, University of New Brunswick, Fredericton, NB, Canada
- *Correspondence: Scott H. Deibel,
| | - S. Higdon
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - T. T. S. Cassell
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - M. L. House-Denine
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - E. Giberson
- Department of Psychology, University of New Brunswick, Fredericton, NB, Canada
| | - I. C. Webb
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - C. M. Thorpe
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, Canada
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Deibel SH, Lewis LM, Cleary J, Cassell TTS, Skinner DM, Thorpe CM. Unpredictable mealtimes rather than social jetlag affects acquisition and retention of hippocampal dependent memory. Behav Processes 2022; 201:104704. [PMID: 35842197 DOI: 10.1016/j.beproc.2022.104704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 01/15/2022] [Accepted: 07/11/2022] [Indexed: 11/19/2022]
Abstract
Some degree of circadian rhythm disruption is hard to avoid in today's society. Along, with many other deleterious effects, circadian rhythm disruption impairs memory. One way to study this is to expose rats to daylengths that are outside the range of entrainment. As a result, circadian processes and behaviours occur during phases of the light dark cycle in which they typically would not. Even brief exposures to these day lengths can impair hippocampal dependent memory. In a recent report, we created an unentrainable light dark cycle that was intended to resemble aspects of social jetlag. As predictable mealtime impacts circadian entrainment, in that report, we also created an unpredictable meal schedule with the idea that failure to entrain to a meal might afford a disadvantage in some instances. Both of these manipulations impaired retention in a spatial water plus-maze task. Using the same manipulations, the present study investigated their effects on acquisition in distributed and massed spatial water plus-maze paradigms. As in other reports with unentrainable daylengths, acquisition was not affected by our lighting manipulation. Conversely, in accordance with our past report, unpredictable mealtimes had a harmful effect on hippocampal dependent memory. Notably, impaired acquisition in the distributed version, and impaired retention in the massed version. In tandem, these data suggest that failure to consolidate or retrieve the information is the likely culprit. The unpredictable mealtime manipulation offers a unique opportunity to study the effects of circadian entrainment on memory.
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Affiliation(s)
- Scott H Deibel
- Department of Psychology, University of New Brunswick, Canada.
| | - Leanna M Lewis
- Department of Psychology, Memorial University of Newfoundland, Canada
| | - Jillian Cleary
- Department of Psychology, Memorial University of Newfoundland, Canada
| | | | - Darlene M Skinner
- Department of Psychology, Memorial University of Newfoundland, Canada
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Jiang L, Liu C, Zhao B, Ma C, Yin Y, Zhou Q, Xu L, Mao R. Time of Day-Dependent Alteration of Hippocampal Rac1 Activation Regulates Contextual Fear Memory in Rats. Front Mol Neurosci 2022; 15:871679. [PMID: 35782392 PMCID: PMC9245039 DOI: 10.3389/fnmol.2022.871679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 05/13/2022] [Indexed: 12/03/2022] Open
Abstract
Fear memory in species varies according to the time of the day. Although the underlying molecular mechanisms have been extensively explored, they remain largely unknown. Here, we report that hippocampal Rac1 activity undergoes a time of day-dependent alteration both in nocturnal rats and diurnal tree shrews and that training at the lower hippocampal Rac1 activation period during the night leads to better contextual fear memory in rats. Furthermore, day and night reversion by 24 h darkness/24 h light housing inverses the external clock time of hippocampal Rac1 activation, but the better contextual fear memory still coincides with the lower Rac1 activation in rats during the night. Interestingly, exogenous melatonin treatment promotes hippocampal Rac1 activity and impairs better contextual fear memory acquired at the lower Rac1 activation period during the night, and Rac1-specific inhibitor NSC23766 compromises the effect of melatonin. These results suggest that the time of day-dependent alteration of hippocampal Rac1 activation regulates contextual fear memory in rats by forgetting.
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Affiliation(s)
- Lizhu Jiang
- CAS Key Laboratory of Animal Models and Human Disease Mechanisms, KIZ-SU Joint Laboratory of Animal Model and Drug Development, Laboratory of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Department of Clinical Psychology, The Third People’s Hospital of Yunnan Province, Kunming, China
- Department of Neuropsychopathy, Clinical Medical School, Dali University, Dali, China
| | - Chao Liu
- CAS Key Laboratory of Animal Models and Human Disease Mechanisms, KIZ-SU Joint Laboratory of Animal Model and Drug Development, Laboratory of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Baizhen Zhao
- CAS Key Laboratory of Animal Models and Human Disease Mechanisms, KIZ-SU Joint Laboratory of Animal Model and Drug Development, Laboratory of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Chen Ma
- CAS Key Laboratory of Animal Models and Human Disease Mechanisms, KIZ-SU Joint Laboratory of Animal Model and Drug Development, Laboratory of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Yan Yin
- Department of Clinical Psychology, The Third People’s Hospital of Yunnan Province, Kunming, China
| | - Qixin Zhou
- CAS Key Laboratory of Animal Models and Human Disease Mechanisms, KIZ-SU Joint Laboratory of Animal Model and Drug Development, Laboratory of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Lin Xu
- CAS Key Laboratory of Animal Models and Human Disease Mechanisms, KIZ-SU Joint Laboratory of Animal Model and Drug Development, Laboratory of Learning and Memory, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
- CAS Centre for Excellence in Brain Science and Intelligent Technology, Shanghai, China
- *Correspondence: Lin Xu,
| | - RongRong Mao
- Department of Pathology and Pathophysiology, School of Basic Medical Science, Kunming Medical University, Kunming, China
- RongRong Mao,
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Delorme TC, Srikanta SB, Fisk AS, Cloutier MÈ, Sato M, Pothecary CA, Merz C, Foster RG, Brown SA, Peirson SN, Cermakian N, Banks GT. Chronic Exposure to Dim Light at Night or Irregular Lighting Conditions Impact Circadian Behavior, Motor Coordination, and Neuronal Morphology. Front Neurosci 2022; 16:855154. [PMID: 35495037 PMCID: PMC9043330 DOI: 10.3389/fnins.2022.855154] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 03/02/2022] [Indexed: 12/24/2022] Open
Abstract
Mistimed exposure to light has been demonstrated to negatively affect multiple aspects of physiology and behavior. Here we analyzed the effects of chronic exposure to abnormal lighting conditions in mice. We exposed mice for 1 year to either: a standard light/dark cycle, a “light-pollution” condition in which low levels of light were present in the dark phase of the circadian cycle (dim light at night, DLAN), or altered light cycles in which the length of the weekday and weekend light phase differed by 6 h (“social jetlag”). Mice exhibited several circadian activity phenotypes, as well as changes in motor function, associated particularly with the DLAN condition. Our data suggest that these phenotypes might be due to changes outside the core clock. Dendritic spine changes in other brain regions raise the possibility that these phenotypes are mediated by changes in neuronal coordination outside of the clock. Given the prevalence of artificial light exposure in the modern world, further work is required to establish whether these negative effects are observed in humans as well.
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Affiliation(s)
- Tara C. Delorme
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, QC, Canada
| | - Shashank B. Srikanta
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, QC, Canada
| | - Angus S. Fisk
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neuroscience Institute, University of Oxford, Oxford, United Kingdom
| | - Marie-Ève Cloutier
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, QC, Canada
| | - Miho Sato
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Carina A. Pothecary
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neuroscience Institute, University of Oxford, Oxford, United Kingdom
| | - Chantal Merz
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Russell G. Foster
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neuroscience Institute, University of Oxford, Oxford, United Kingdom
| | - Steven A. Brown
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Stuart N. Peirson
- Nuffield Department of Clinical Neurosciences, Sleep and Circadian Neuroscience Institute, University of Oxford, Oxford, United Kingdom
| | - Nicolas Cermakian
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montréal, QC, Canada
- *Correspondence: Nicolas Cermakian,
| | - Gareth T. Banks
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire, United Kingdom
- Gareth T. Banks,
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12
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Litopenaeus vannamei BMAL1 Is a Critical Mediator Regulating the Expression of Glucose Transporters and Can Be Suppressed by Constant Darkness. Animals (Basel) 2021; 11:ani11102893. [PMID: 34679914 PMCID: PMC8532828 DOI: 10.3390/ani11102893] [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: 07/28/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 11/28/2022] Open
Abstract
Simple Summary Growing evidence has indicated that glucose absorption exhibits profound circadian rhythmicity, mediated entirely by glucose transporters. We observed that the daily profile of BMAL1, GLUT1 and SGLT1 expression was also synchronized in the intestine and the hepatopancreas of Litopenaeus vannamei. Our result identified for the first time that BMAL1 is a critical mediator regulating the expression of glucose transporters, which could be suppressed by constant darkness in L. vannamei. Abstract Aryl hydrocarbon receptor nuclear translocator-like protein 1 (BMAL1) is a core circadian transcription factor that controls the 24-h cycle of physiological processes. In shrimp, the role of BMAL1 in the regulating glucose metabolism remains unclear. Firstly, we observed that the daily profile of BMAL1, GLUT1 and SGLT1 expression were synchronized in the intestine and the hepatopancreas of Litopenaeus vannamei. Then we examined the effects of BMAL1 on the gene expression of glucose transporter type 1 (SGLT1) and sodium-glucose cotransporter 1 (GLUT1) in vivo and in vitro. BMAL1 in L. vannamei shares 70.91–96.35% of sequence identities with other shrimp species and possesses the conserved helix-loop-helix domain and polyadenylation site domain. The in vitro dual-luciferase reporter assay and in vivo RNA interference experiment demonstrated that BMAL1 exerted a positive regulation effect on the expression of glucose transporters in L. vannamei. Moreover, we conducted an eight-week treatment to investigate whether light/dark cycle change would influence growth performance, and gene expression of BMAL1, GLUT1 and SGLT1 in L. vannamei. Our result showed that compared with natural light treatment, constant darkness (24-h darkness) significantly decreased (p < 0.05) serum glucose concentration, and suppressed (p < 0.05) the gene expression of BMAL1, GLUT1 and SGLT1 in the hepatopancreas and the intestine. Growth performance and survival rate were also decreased (p < 0.05) by constant darkness treatment. Our result identified BMAL1 as a critical mediator regulating the expression of glucose transporters, which could be suppressed by constant darkness in L. vannamei. It would be quite interesting to explore the mechanism of dark/light cycles on glucose transport and metabolism in L. vannamei, which might provide a feeding strategy for improving carbohydrate utilization in the future.
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13
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Dim light in the evening causes coordinated realignment of circadian rhythms, sleep, and short-term memory. Proc Natl Acad Sci U S A 2021; 118:2101591118. [PMID: 34556572 PMCID: PMC8488663 DOI: 10.1073/pnas.2101591118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2021] [Indexed: 12/28/2022] Open
Abstract
In modern societies, people are regularly exposed to artificial light (e.g., light-emitting electronic devices). Dim light in the evening (DLE) imposes an artificial extension of the solar day, increasing our alertness before bedtime, delaying melatonin timing and sleep onset, and increasing sleepiness in the next morning. Using laboratory mice as a model organism, we show that 2 wk of 4-h, 20-lux DLE postpones rest–activity rhythms, delays molecular rhythms in the brain and body, and reverses the diurnal pattern of short-term memory performance. These results highlight the biological impact of DLE and emphasize the need to optimize our evening light exposure if we are to avoid shifting our biological clocks. Light provides the primary signal for entraining circadian rhythms to the day/night cycle. In addition to rods and cones, the retina contains a small population of photosensitive retinal ganglion cells (pRGCs) expressing the photopigment melanopsin (OPN4). Concerns have been raised that exposure to dim artificial lighting in the evening (DLE) may perturb circadian rhythms and sleep patterns, and OPN4 is presumed to mediate these effects. Here, we examine the effects of 4-h, 20-lux DLE on circadian physiology and behavior in mice and the role of OPN4 in these responses. We show that 2 wk of DLE induces a phase delay of ∼2 to 3 h in mice, comparable to that reported in humans. DLE-induced phase shifts are unaffected in Opn4−/− mice, indicating that rods and cones are capable of driving these responses in the absence of melanopsin. DLE delays molecular clock rhythms in the heart, liver, adrenal gland, and dorsal hippocampus. It also reverses short-term recognition memory performance, which is associated with changes in preceding sleep history. In addition, DLE modifies patterns of hypothalamic and cortical cFos signals, a molecular correlate of recent neuronal activity. Together, our data show that DLE causes coordinated realignment of circadian rhythms, sleep patterns, and short-term memory process in mice. These effects are particularly relevant as DLE conditions―due to artificial light exposure―are experienced by the majority of the populace on a daily basis.
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14
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Kumari R, Verma V, Kronfeld-Schor N, Singaravel M. Differential response of diurnal and nocturnal mammals to prolonged altered light-dark cycle: a possible role of mood associated endocrine, inflammatory and antioxidant system. Chronobiol Int 2021; 38:1618-1630. [PMID: 34128442 DOI: 10.1080/07420528.2021.1937200] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The circadian system maintains internal 24 h oscillation of behavior and physiology, and its misalignment with external light-dark (LD) cycle results in negative health outcomes. In order to elucidate the effect of prolonged constant condition and the differences in the response between nocturnal and diurnal species, we studied the effects of constant light (LL) and constant darkness (DD) on a diurnal (squirrel) and a nocturnal (mouse) rodent species, focusing on the endocrine, inflammatory and antioxidant systems associated with depression-like behavior. Squirrels and mice (n = 10/group) were placed in chronocubicle under 12:12 h LD cycle, LL and DD. After 4 weeks, animals were subjected to sucrose preference test and blood and brain tissues were collected for measuring melatonin, corticosterone, proinflammatory cytokine, tumor necrosis factor-α (TNF-α) and the activity of primary antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD). The results show that in diurnal squirrels, prolonged constant darkness reduced sucrose preference, CAT, and SOD, increased corticosterone and TNF-α levels, but caused no significant change in the melatonin compared to LD condition. In contrast, in nocturnal mice constant darkness caused no significant changes in sucrose preference and corticosterone levels, increased melatonin, CAT and SOD levels but decreased TNF-α levels. Chronic LL caused a similar response in both squirrels and mice: it decreased sucrose preference, melatonin, CAT and SOD levels but increased corticosterone and TNF-α levels. Together, the study demonstrates differential effects of altered light-dark cycle in a diurnal and a nocturnal rodent on interrelated endocrine, inflammatory and antioxidant systems associated with depression-like behavior, with constant light having adverse effects on both species but constant darkness having a negative effect mainly in the diurnal squirrels.
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Affiliation(s)
- Ruchika Kumari
- Chronobiology Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Vivek Verma
- Chronobiology Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Noga Kronfeld-Schor
- Ecological and Evolutionary Physiology Laboratory, School of Zoology and Sagol School of Neuroscience, Faculty of Life Sciences, Tel Aviv University, Tel-Aviv, Israel
| | - Muniyandi Singaravel
- Chronobiology Laboratory, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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15
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Clark JW, Daykin H, Metha JA, Allocca G, Hoyer D, Drummond SPA, Jacobson LH. Manipulation of REM sleep via orexin and GABAA receptor modulators differentially affects fear extinction in mice: effect of stable versus disrupted circadian rhythm. Sleep 2021; 44:6171207. [PMID: 33720375 DOI: 10.1093/sleep/zsab068] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 01/22/2021] [Indexed: 12/18/2022] Open
Abstract
Sleep disruption, and especially REM sleep disruption, is associated with fear inhibition impairment in animals and humans. The REM sleep-fear inhibition relationship raises concern for individuals with PTSD, whose sleep disturbance is commonly treated with hypnotics which disrupt and/or decrease REM sleep, such as benzodiazepines or 'Z-drugs'. Here, we examined the effects of the Z-drug zolpidem, a GABAA receptor positive allosteric modulator, as well as suvorexant, an orexin receptor antagonist (hypnotics which decrease and increase REM sleep, respectively) in the context of circadian disruption in murine models of fear inhibition-related processes (i.e., fear extinction and safety learning). Adult male C57Bl/6J mice completed fear and safety conditioning before undergoing shifts in the light-dark (LD) cycle or maintaining a consistent LD schedule. Fear extinction and recall of conditioned safety were thereafter tested daily. Immediately prior to onset of the light phase between testing sessions, mice were treated with zolpidem, suvorexant, or vehicle (methylcellulose). EEG/EMG analysis showed temporal distribution of REM sleep was misaligned during LD cycle-shifts, while REM sleep duration was preserved. Suvorexant increased REM sleep and improved fear extinction rate, relative to zolpidem, which decreased REM sleep. Survival analysis demonstrated LD shifted mice treated with suvorexant were faster to achieve complete extinction than vehicle and zolpidem-treated mice in the LD shifted condition. By contrast, retention of conditioned safety memory was not influenced by either treatment. This study thus provides preclinical evidence for the potential clinical utility of hypnotics which increase REM sleep for fear extinction after PTSD-relevant sleep disturbance.
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Affiliation(s)
- Jacob W Clark
- School of Psychological Sciences and Turner Institute for Brain and Mental Health, Monash University, VIC, Australia.,Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
| | - Heather Daykin
- Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
| | - Jeremy A Metha
- Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia.,Brain, Mind and Markets Laboratory, Department of Finance, The University of Melbourne, VIC, Australia
| | - Giancarlo Allocca
- Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia.,Somnivore Pty. Ltd., Bacchus Marsh, Victoria, Australia
| | - Daniel Hoyer
- Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia.,Department of Molecular Medicine, The Scripps Research Institute, CA, The United States of America
| | - Sean P A Drummond
- School of Psychological Sciences and Turner Institute for Brain and Mental Health, Monash University, VIC, Australia
| | - Laura H Jacobson
- Department of Pharmacology and Therapeutics, The University of Melbourne, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, VIC, Australia
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16
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Hussein AAA, Baz ES, Mariën J, Tadros MM, El-Shenawy NS, Koene JM. Effect of photoperiod and light intensity on learning ability and memory formation of the pond snail Lymnaea stagnalis. INVERTEBRATE NEUROSCIENCE : IN 2020; 20:18. [PMID: 33078292 PMCID: PMC7572358 DOI: 10.1007/s10158-020-00251-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 10/06/2020] [Indexed: 11/29/2022]
Abstract
Natural light is regarded as a key regulator of biological systems and typically serves as a Zeitgeber for biological rhythms. As a natural abiotic factor, it is recognized to regulate multiple behavioral and physiological processes in animals. Disruption of the natural light regime due to light pollution may result in significant effects on animal learning and memory development. Here, we investigated whether sensitivity to various photoperiods or light intensities had an impact on intermediate-term memory (ITM) and long-term memory (LTM) formation in the pond snail Lymnaea stagnalis. We also investigated the change in the gene expression level of molluscan insulin-related peptide II (MIP II) is response to the given light treatments. The results show that the best light condition for proper LTM formation is exposure to a short day (8 h light) and low light intensity (1 and 10 lx). Moreover, the more extreme light conditions (16 h and 24 h light) prevent the formation of both ITM and LTM. We found no change in MIP II expression in any of the light treatments, which may indicate that MIP II is not directly involved in the operant conditioning used here, even though it is known to be involved in learning. The finding that snails did not learn in complete darkness indicates that light is a necessary factor for proper learning and memory formation. Furthermore, dim light enhances both ITM and LTM formation, which suggests that there is an optimum since both no light and too bright light prevented learning and memory. Our findings suggest that the upsurge of artificial day length and/or night light intensity may also negatively impact memory consolidation in the wild.
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Affiliation(s)
- Ahmed A A Hussein
- Department of Zoology, Faculty of Science, Suez Canal University, Ismailia, Egypt.
- Department of Ecological Science, Faculty of Science, Vrije Universiteit, Amsterdam, The Netherlands.
- Malacology Lab, Theodor Bilharz Research Institute (TBRI), Giza, Egypt.
| | - El-Sayed Baz
- Department of Zoology, Faculty of Science, Suez Canal University, Ismailia, Egypt.
| | - Janine Mariën
- Department of Ecological Science, Faculty of Science, Vrije Universiteit, Amsterdam, The Netherlands
| | - Menerva M Tadros
- Malacology Lab, Theodor Bilharz Research Institute (TBRI), Giza, Egypt
| | - Nahla S El-Shenawy
- Department of Zoology, Faculty of Science, Suez Canal University, Ismailia, Egypt
| | - Joris M Koene
- Department of Ecological Science, Faculty of Science, Vrije Universiteit, Amsterdam, The Netherlands
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17
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Deibel SH, Rota R, Steenland HW, Ali K, McNaughton BL, Tatsuno M, McDonald RJ. Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle. Front Neurosci 2020; 14:551843. [PMID: 33122986 PMCID: PMC7573124 DOI: 10.3389/fnins.2020.551843] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 09/03/2020] [Indexed: 12/29/2022] Open
Abstract
Circadian rhythm misalignment has a deleterious impact on the brain and the body. In rats, exposure to a 21-hour day length impairs hippocampal dependent memory. Sleep, and particularly K-complexes and sleep spindles in the cortex, have been hypothesized to be involved in memory consolidation. Altered K-complexes, sleep spindles, or interaction between the cortex and hippocampus could be a mechanism for the memory consolidation failure but has yet to be assessed in any circadian misalignment paradigm. In the current study, continuous local field potential recordings from five rats were used to assess the changes in aspects of behavior and sleep, including wheel running activity, quiet wakefulness, motionless sleep, slow wave sleep, REM sleep, K-complexes and sleep spindles, in rats exposed to six consecutive days of a T21 light-dark cycle (L9:D12). Except for a temporal redistribution of sleep and activity during the T21, there were no changes in period, or total amount for any aspect of sleep or activity. These data suggest that the memory impairment elicited from 6 days of T21 exposure is likely not due to changes in sleep architecture. It remains possible that hippocampal plasticity is affected by experiencing light when subjective circadian phase is calling for dark. However, if there is a reduction in hippocampal plasticity, changes in sleep appear not to be driving this effect.
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Affiliation(s)
- Scott H Deibel
- Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Ryan Rota
- Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Hendrik W Steenland
- Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada.,NeuroTek Innovative Technology Inc., Toronto, ON, Canada
| | - Karim Ali
- Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Bruce L McNaughton
- Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada.,Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Masami Tatsuno
- Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Robert J McDonald
- Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
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18
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Circadian disruption impairs fear extinction and memory of conditioned safety in mice. Behav Brain Res 2020; 393:112788. [DOI: 10.1016/j.bbr.2020.112788] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 06/21/2020] [Accepted: 06/22/2020] [Indexed: 02/06/2023]
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19
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Hartsock MJ, Spencer RL. Memory and the circadian system: Identifying candidate mechanisms by which local clocks in the brain may regulate synaptic plasticity. Neurosci Biobehav Rev 2020; 118:134-162. [PMID: 32712278 DOI: 10.1016/j.neubiorev.2020.07.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 07/14/2020] [Accepted: 07/18/2020] [Indexed: 12/11/2022]
Abstract
The circadian system is an endogenous biological network responsible for coordinating near-24-h cycles in behavior and physiology with daily timing cues from the external environment. In this review, we explore how the circadian system regulates memory formation, retention, and recall. Circadian rhythms in these memory processes may arise through several endogenous pathways, and recent work highlights the importance of genetic timekeepers found locally within tissues, called local clocks. We evaluate the circadian memory literature for evidence of local clock involvement in memory, identifying potential nodes for direct interactions between local clock components and mechanisms of synaptic plasticity. Our discussion illustrates how local clocks may pervasively modulate neuronal plastic capacity, a phenomenon that we designate here as circadian metaplasticity. We suggest that this function of local clocks supports the temporal optimization of memory processes, illuminating the potential for circadian therapeutic strategies in the prevention and treatment of memory impairment.
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Affiliation(s)
- Matthew J Hartsock
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
| | - Robert L Spencer
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
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20
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Deibel SH, McDonald RJ, Kolla NJ. Are Owls and Larks Different When it Comes to Aggression? Genetics, Neurobiology, and Behavior. Front Behav Neurosci 2020; 14:39. [PMID: 32256322 PMCID: PMC7092663 DOI: 10.3389/fnbeh.2020.00039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/25/2020] [Indexed: 12/16/2022] Open
Abstract
This review focuses on the contribution of circadian rhythms to aggression with a multifaceted approach incorporating genetics, neural networks, and behavior. We explore the hypothesis that chronic circadian misalignment is contributing to increased aggression. Genes involved in both circadian rhythms and aggression are discussed as a possible mechanism for increased aggression that might be elicited by circadian misalignment. We then discuss the neural networks underlying aggression and how dysregulation in the interaction of these networks evoked by circadian rhythm misalignment could contribute to aggression. The last section of this review will present recent human correlational data demonstrating the association between chronotype and/or circadian misalignment with aggression. With circadian rhythms and aggression being a burgeoning area of study, we hope that this review initiates more interest in this promising and topical area.
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Affiliation(s)
- Scott H Deibel
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Robert J McDonald
- Department of Neuroscience, University of Lethbridge, Lethbridge, AL, Canada
| | - Nathan J Kolla
- Waypoint Centre for Mental Health Care, Penetanguishene, ON, Canada.,Centre for Addiction and Mental Health, Toronto, ON, Canada.,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
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21
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Kordestani-Moghadam P, Nasehi M, Khodagholi F, Vaseghi S, Zarrindast MR, Khani M. The fluctuations of metabotropic glutamate receptor subtype 5 (mGluR5) in the amygdala in fear conditioning model of male Wistar rats following sleep deprivation, reverse circadian and napping. Brain Res 2020; 1734:146739. [PMID: 32087111 DOI: 10.1016/j.brainres.2020.146739] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/15/2020] [Accepted: 02/18/2020] [Indexed: 12/20/2022]
Abstract
Sleep is involved in metabolic system, mental health and cognitive functions. Evidence shows that sleep deprivation (SD) negatively affects mental health and impairs cognitive functions, including learning and memory. Furthermore, the metabotropic glutamate receptor subtype 5 (mGluR5) is a metabolic biomarker, which is affected by various conditions, including stress, sleep deprivation, and cognitive and psychiatric disorders. In this research, we investigated the effect of SD and reverse circadian (RC), and two models of napping (continuous and non-continuous) combined with SD or RC on fear-conditioning memory, anxiety-like behavior and mGluR5 fluctuations in the amygdala. 64 male Wistar rats were used in this study. The water box apparatus was used to induce SD/RC for 48 h, and fear-conditioning memory apparatus was used to assess fear memory. The results showed, fear-conditioning memory was impaired following SD and RC, especially in contextual stage. However, anxiety-like behavior was increased. Furthermore, mGluR5 was increased in the left amygdala more than the right amygdala. Additionally, continuous napping significantly improved fear-conditioning memory, especially freezing behavior. In conclusion, following SD and RC, fear-conditioning memory in contextual stage is more vulnerable than in auditory stage. Furthermore, increase in anxiety-like behavior is related to increase in the activity of left amygdala and mGluR5 receptors.
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Affiliation(s)
| | - Mohammad Nasehi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
| | - Fariba Khodagholi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Salar Vaseghi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad-Reza Zarrindast
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Neuroendocrinology, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Institute for Cognitive Science Studies (ICSS), Tehran, Iran
| | - Mojgan Khani
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
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22
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Newman AW, Deibel SH, Lewis LM, Viguers KB, Thorpe CM. Brief circadian rhythm disruption does not impair hippocampal dependent memory when rats are over-trained and given more re-entrainment days. LEARNING AND MOTIVATION 2020. [DOI: 10.1016/j.lmot.2020.101613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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23
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Lewis LM, Deibel SH, Cleary J, Viguers KB, Jones KA, Skinner DM, Hallett D, Thorpe CM. Learning and memory in a rat model of social jetlag that also incorporates mealtime. BIOL RHYTHM RES 2020. [DOI: 10.1080/09291016.2020.1716557] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Leanna M. Lewis
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
| | - Scott H. Deibel
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
| | - Jillian Cleary
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
| | - Kayla B. Viguers
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
| | - Karen A. Jones
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
| | - Darlene M. Skinner
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
| | - Darcy Hallett
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
| | - Christina M. Thorpe
- Department of Psychology, Memorial University of Newfoundland, St. John’s, NL, USA
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24
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Horsey EA, Maletta T, Turner H, Cole C, Lehmann H, Fournier NM. Chronic Jet Lag Simulation Decreases Hippocampal Neurogenesis and Enhances Depressive Behaviors and Cognitive Deficits in Adult Male Rats. Front Behav Neurosci 2020; 13:272. [PMID: 31969809 PMCID: PMC6960209 DOI: 10.3389/fnbeh.2019.00272] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Accepted: 11/29/2019] [Indexed: 11/13/2022] Open
Abstract
There is a long history that protracted periods of circadian disruption, such as through frequent transmeridian travel or rotating shift work, can have a significant impact on brain function and health. In addition, several studies have shown that chronic periods of circadian misalignment can be a significant risk factor for the development of depression and anxiety in some individuals with a history of psychiatric illness. In animal models, circadian disruption can be introduced through either phase advances or delays in the light-dark cycle. However, the impact of chronic phase shifts on affective behavior in rats has not been well-studied. In the present study, male rats were subjected to either weekly 6 h phase advances (e.g., traveling eastbound from New York to Paris) or 6 h phase delays (e.g., traveling westbound from New York to Hawaii) in their light/dark cycle for 8 weeks. The effect of chronic phase shifts was then examined on a range of emotional and cognitive behaviors. We found that rats exposed to frequent phase advances, which mirror conditions of chronic jet lag in humans, exhibited impairments in object recognition memory and showed signature symptoms of depression, including anhedonia, increased anxiety behavior, and higher levels of immobility in the forced swim test. In addition, rats housed on the phase advance schedule also had lower levels of hippocampal neurogenesis and immature neurons showed reduced dendritic complexity compared to controls. These behavioral and neurogenic changes were direction-specific and were not observed after frequent phase delays. Taken together, these findings support the view that circadian disruption through chronic jet lag exposure can suppress hippocampal neurogenesis, which can have a significant impact on memory and mood-related behaviors.
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Affiliation(s)
- Emily A Horsey
- Department of Psychology, Trent University, Peterborough, ON, Canada
| | - Teresa Maletta
- Department of Psychology, Trent University, Peterborough, ON, Canada
| | - Holly Turner
- Department of Psychology, Trent University, Peterborough, ON, Canada
| | - Chantel Cole
- Department of Psychology, Trent University, Peterborough, ON, Canada
| | - Hugo Lehmann
- Department of Psychology, Trent University, Peterborough, ON, Canada
| | - Neil M Fournier
- Department of Psychology, Trent University, Peterborough, ON, Canada
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25
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Borras C, Ingles M, Mas-Bargues C, Dromant M, Sanz-Ros J, Román-Domínguez A, Gimeno-Mallench L, Gambini J, Viña J. Centenarians: An excellent example of resilience for successful ageing. Mech Ageing Dev 2019; 186:111199. [PMID: 31899226 DOI: 10.1016/j.mad.2019.111199] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 12/17/2019] [Accepted: 12/19/2019] [Indexed: 12/13/2022]
Abstract
Centenarians are remarkable not only because of their prolonged life, but also because they compress morbidity until the very last moments of their lives, thus being proposed as a model of successful, extraordinary ageing. From the medical viewpoint, centenarians do not escape the physiological decline or the age-related diseases or syndromes (i.e. frailty), but the rate of such processes is slow enough to be counterbalanced by their increased intrinsic capacity to respond to minor stresses of daily life (i.e. resilience). These new concepts are reviewed in this paper. Allostatic stresses lead to a chronic low-grade inflammation that has led to the proposal of the "inflammaging" theory of ageing and frailty. The biology of centenarians, described in this review, provides us with clues for intervention to promote healthy ageing in the general population. One of the major reasons for this healthy ageing has to do with the genetic signature that is specific for centenarians and certainly different from octogenarians who do not enjoy the extraordinary qualities of centenarians.
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Affiliation(s)
- C Borras
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain.
| | - M Ingles
- Freshage Research Group, Department of Physiotherapy, Faculty of Physiotherapy, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
| | - C Mas-Bargues
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
| | - M Dromant
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
| | - J Sanz-Ros
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
| | - A Román-Domínguez
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
| | - L Gimeno-Mallench
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
| | - J Gambini
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
| | - J Viña
- Freshage Research Group, Department of Physiology, Faculty of Medicine, University of Valencia, CIBERFES-ISCIII, INCLIVA, Valencia, Spain
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den Boon FS, de Vries T, Baelde M, Joëls M, Karst H. Circadian and Ultradian Variations in Corticosterone Level Influence Functioning of the Male Mouse Basolateral Amygdala. Endocrinology 2019; 160:791-802. [PMID: 30689790 DOI: 10.1210/en.2018-00767] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 01/15/2019] [Indexed: 12/20/2022]
Abstract
The hypothalamic-pituitary-adrenal axis involves timed signaling between the hypothalamus, pituitary, and adrenal glands and back to the brain, causing an inherently oscillating system. Corticosteroids such as corticosterone (CORT) are secreted in a circadian rhythm, characterized by low and high levels at the start of the inactive and active phases, respectively. The circadian rhythm overarches ultradian CORT pulses, with approximate 1-hour interpulse intervals. We examined the physiological relevance of pulsatile CORT exposure for neurons of the basolateral amygdala (BLA), an area important for fear learning. We first applied four pulses of equal, high CORT concentration and measured the frequency of miniature excitatory postsynaptic currents (mEPSCs) reflecting spontaneous glutamate signaling. BLA neurons responded differently to each pulse, showing "metaplasticity," extending earlier studies. Next, we mimicked the progression of the inactive and active phases by four CORT pulses of increasing and decreasing concentrations, respectively. CORT pulses of increasing concentration were necessary and sufficient to gradually increase baseline (between-pulse) mEPSC frequency during the mimicked inactive phase, whereas the opposite was seen with decreasing CORT levels during the mimicked active phase. To study the relevance of changed glutamate transmission on behavior, mice were tested in tone-cued fear conditioning during the active or inactive phase. Animals tested at the inactive compared with the active phase showed efficient fear learning; this was also observed when animals tested during the active phase were treated with the CORT synthesis blocker metyrapone. This suggests that natural CORT rhythms influence electrical activity in the BLA, possibly contributing to altered behavioral function.
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Affiliation(s)
- Femke Susanne den Boon
- Deparment of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht University, Utrecht, Netherlands
| | - Tessa de Vries
- Deparment of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht University, Utrecht, Netherlands
| | - Marin Baelde
- Deparment of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht University, Utrecht, Netherlands
| | - Marian Joëls
- Deparment of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht University, Utrecht, Netherlands
- University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Henk Karst
- Deparment of Translational Neuroscience, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht University, Utrecht, Netherlands
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Rao R, Androulakis IP. The physiological significance of the circadian dynamics of the HPA axis: Interplay between circadian rhythms, allostasis and stress resilience. Horm Behav 2019; 110:77-89. [PMID: 30862458 DOI: 10.1016/j.yhbeh.2019.02.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 01/23/2019] [Accepted: 02/28/2019] [Indexed: 01/12/2023]
Abstract
Circadian time-keeping mechanisms preserve homeostasis by synchronizing internal physiology with predictable variations in the environment and temporally organize the activation of physiological signaling mechanisms to promote survival and optimize the allocation of energetic resources. In this paper, we highlight the importance of the robust circadian dynamics of allostatic mediators, with a focus on the hypothalamic-pituitary-adrenal (HPA) axis, for the optimal regulation of host physiology and in enabling organisms to adequately respond and adapt to physiological stressors. We review studies showing how the chronic disruption of circadian rhythms can result in the accumulation of allostatic load, which impacts the appropriate functioning of physiological systems and diminishes the resilience of internal systems to adequately respond to subsequent stressors. A careful consideration of circadian rhythm dynamics leads to a more comprehensive characterization of individual variability in allostatic load and stress resilience. Finally, we suggest that the restoration of circadian rhythms after pathological disruption can enable the re-engagement of allostatic mechanisms and re-establish stress resilience.
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Affiliation(s)
- Rohit Rao
- Chemical & Biochemical Engineering Department, Rutgers University, Piscataway, NJ, United States of America
| | - Ioannis P Androulakis
- Chemical & Biochemical Engineering Department, Rutgers University, Piscataway, NJ, United States of America; Biomedical Engineering Department, Rutgers University, Piscataway, NJ, United States of America; Department of Surgery, Rutgers - Robert Wood Johnson Medical School, New Brunswick, NJ, United States of America.
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28
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Daut RA, Hartsock MJ, Tomczik AC, Watkins LR, Spencer RL, Maier SF, Fonken LK. Circadian misalignment has differential effects on affective behavior following exposure to controllable or uncontrollable stress. Behav Brain Res 2019; 359:440-445. [PMID: 30312639 PMCID: PMC9826731 DOI: 10.1016/j.bbr.2018.10.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 10/04/2018] [Accepted: 10/07/2018] [Indexed: 01/11/2023]
Abstract
In modern 24 h society, circadian disruption is pervasive, arising from night shift work, air travel across multiple time zones, irregular sleep schedules, and exposure to artificial light at night. Disruption of the circadian system is associated with many adverse health consequences, including mood disorders. Here we investigate whether inducing circadian misalignment using a phase advance protocol interferes with the ability to cope with a stressor, thereby increasing susceptibility to the negative consequences of stress. Male rats were maintained on a standard 12:12 light: dark (LD) cycle or subjected to a chronic phase advance (CPA) protocol involving 4 weekly 6 h phase shifts (earlier light onset) of the LD cycle. Rats were then exposed to escapable stress (ES), inescapable stress (IS), or no stress (home cage control; HC) and performance on juvenile social exploration and active escape learning in the two-way shuttlebox test was assessed 24 h and 48 h following stress, respectively. CPA alone had no effect on pre-stress juvenile social exploration, and it also did not interfere with the protective effect of ES on the stress-induced reduction in juvenile social exploration. In contrast, CPA impaired escape learning in the two-way shuttlebox to the same extent as IS in all subjects, regardless of stress history. Additionally, CPA produced somatic alterations that included increased body mass, increased epididymal adiposity, and decreased adrenal mass. These data indicate that CPA differentially modulated the stress-protective effects of behavioral control depending on the type of affective behavior examined.
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29
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Schosserer M, Banks G, Dogan S, Dungel P, Fernandes A, Marolt Presen D, Matheu A, Osuchowski M, Potter P, Sanfeliu C, Tuna BG, Varela-Nieto I, Bellantuono I. Modelling physical resilience in ageing mice. Mech Ageing Dev 2018; 177:91-102. [PMID: 30290161 PMCID: PMC6445352 DOI: 10.1016/j.mad.2018.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 09/12/2018] [Accepted: 10/01/2018] [Indexed: 02/06/2023]
Abstract
Geroprotectors, a class of drugs targeting multiple deficits occurring with age, necessitate the development of new animal models to test their efficacy. The COST Action MouseAGE is a European network whose aim is to reach consensus on the translational path required for geroprotectors, interventions targeting the biology of ageing. In our previous work we identified frailty and loss of resilience as a potential target for geroprotectors. Frailty is the result of an accumulation of deficits, which occurs with age and reduces the ability to respond to adverse events (physical resilience). Modelling frailty and physical resilience in mice is challenging for many reasons. There is no consensus on the precise definition of frailty and resilience in patients or on how best to measure it. This makes it difficult to evaluate available mouse models. In addition, the characterization of those models is poor. Here we review potential models of physical resilience, focusing on those where there is some evidence that the administration of acute stressors requires integrative responses involving multiple tissues and where aged mice showed a delayed recovery or a worse outcome then young mice in response to the stressor. These models include sepsis, trauma, drug- and radiation exposure, kidney and brain ischemia, exposure to noise, heat and cold shock.
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Affiliation(s)
- Markus Schosserer
- University of Natural Resources and Life Sciences, Vienna, Department of Biotechnology, Vienna, Austria
| | - Gareth Banks
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire, OX11 0RD, United Kingdom
| | - Soner Dogan
- Department of Medical Biology, School of Medicine, Yeditepe University, Istanbul, Turkey
| | - Peter Dungel
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria
| | - Adelaide Fernandes
- Neuron-Glia Biology in Health and Disease, iMed.ULisboa, Research Institute for Medicines, Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal
| | - Darja Marolt Presen
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria
| | - Ander Matheu
- Oncology Department, Biodonostia Research Institute, San Sebastián, Spain
| | - Marcin Osuchowski
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria
| | - Paul Potter
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire, OX11 0RD, United Kingdom
| | - Coral Sanfeliu
- Institute of Biomedical Research of Barcelona (IIBB) CSIC, IDIBAPS, CIBERESP, Barcelona, Spain
| | - Bilge Guvenc Tuna
- Department of Medical Biophysics, School of Medicine, Yeditepe University, Istanbul, Turkey
| | | | - Ilaria Bellantuono
- MRC/Arthritis Research-UK Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Department of Oncology and Metabolism, The Medical School, Beech Hill Road, Sheffield, S10 2RX, United Kingdom.
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Fisk AS, Tam SKE, Brown LA, Vyazovskiy VV, Bannerman DM, Peirson SN. Light and Cognition: Roles for Circadian Rhythms, Sleep, and Arousal. Front Neurol 2018; 9:56. [PMID: 29479335 PMCID: PMC5811463 DOI: 10.3389/fneur.2018.00056] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 01/22/2018] [Indexed: 01/12/2023] Open
Abstract
Light exerts a wide range of effects on mammalian physiology and behavior. As well as synchronizing circadian rhythms to the external environment, light has been shown to modulate autonomic and neuroendocrine responses as well as regulating sleep and influencing cognitive processes such as attention, arousal, and performance. The last two decades have seen major advances in our understanding of the retinal photoreceptors that mediate these non-image forming responses to light, as well as the neural pathways and molecular mechanisms by which circadian rhythms are generated and entrained to the external light/dark (LD) cycle. By contrast, our understanding of the mechanisms by which lighting influences cognitive processes is more equivocal. The effects of light on different cognitive processes are complex. As well as the direct effects of light on alertness, indirect effects may also occur due to disrupted circadian entrainment. Despite the widespread use of disrupted LD cycles to study the role circadian rhythms on cognition, the different experimental protocols used have subtly different effects on circadian function which are not always comparable. Moreover, these protocols will also disrupt sleep and alter physiological arousal, both of which are known to modulate cognition. Studies have used different assays that are dependent on different cognitive and sensory processes, which may also contribute to their variable findings. Here, we propose that studies addressing the effects of different lighting conditions on cognitive processes must also account for their effects on circadian rhythms, sleep, and arousal if we are to fully understand the physiological basis of these responses.
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Affiliation(s)
- Angus S Fisk
- Sleep and Circadian Neuroscience Institute (SCNi), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Shu K E Tam
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Laurence A Brown
- Sleep and Circadian Neuroscience Institute (SCNi), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Vladyslav V Vyazovskiy
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - David M Bannerman
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Stuart N Peirson
- Sleep and Circadian Neuroscience Institute (SCNi), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
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Circadian Rhythms in Fear Conditioning: An Overview of Behavioral, Brain System, and Molecular Interactions. Neural Plast 2017; 2017:3750307. [PMID: 28698810 PMCID: PMC5494081 DOI: 10.1155/2017/3750307] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/28/2017] [Accepted: 05/14/2017] [Indexed: 12/17/2022] Open
Abstract
The formation of fear memories is a powerful and highly evolutionary conserved mechanism that serves the behavioral adaptation to environmental threats. Accordingly, classical fear conditioning paradigms have been employed to investigate fundamental molecular processes of memory formation. Evidence suggests that a circadian regulation mechanism allows for a timestamping of such fear memories and controlling memory salience during both their acquisition and their modification after retrieval. These mechanisms include an expression of molecular clocks in neurons of the amygdala, hippocampus, and medial prefrontal cortex and their tight interaction with the intracellular signaling pathways that mediate neural plasticity and information storage. The cellular activities are coordinated across different brain regions and neural circuits through the release of glucocorticoids and neuromodulators such as acetylcholine, which integrate circadian and memory-related activation. Disturbance of this interplay by circadian phase shifts or traumatic experience appears to be an important factor in the development of stress-related psychopathology, considering these circadian components are of critical importance for optimizing therapeutic approaches to these disorders.
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Cissé YM, Peng J, Nelson RJ. Effects of Dim Light at Night on Food Intake and Body Mass in Developing Mice. Front Neurosci 2017; 11:294. [PMID: 28603481 PMCID: PMC5445163 DOI: 10.3389/fnins.2017.00294] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 05/09/2017] [Indexed: 11/26/2022] Open
Abstract
Appropriately timed light is critical for circadian organization; exposure to dim light at night (dLAN) disrupts temporal organization of endogenous biological timing. Exposure to dLAN in adult mice is associated with elevated body mass and changes in metabolism putatively driven by voluntary changes in the time of food intake. We predicted that exposure of young mice to LAN could affect adult metabolic function. At 3 weeks (Experiment 1) or 5 weeks (Experiment 2) of age, mice were either maintained in standard light-dark (DARK) cycles or exposed to nightly dLAN (5 lux). In the first two experiments, food intake and locomotor activity were assessed after 4 weeks and a glucose tolerance test was administered after 6 weeks in experimental lighting conditions. In Experiment 3, tissues were collected around the clock at 6 h intervals to investigate rhythmic hepatic clock gene expression in mice exposed to dLAN from 3 or 5 weeks of age. Male and female mice exposed to dLAN beginning at 3 weeks of age displayed similar growth rates and body mass to DARK-reared offspring, despite increasing day-time food intake. Exposure to dLAN beginning at 5 weeks of age increased body mass and daytime food intake in male, but not female, mice. Consistent with the body mass phenotype, clock gene expression was unaltered in the liver. In contrast to adults, dLAN exposure during the development of the peripheral circadian system has sex- and development-dependent effects on body mass gain.
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Affiliation(s)
- Yasmine M Cissé
- Behavioral Neuroendocrinology Group, Department of Neuroscience, Neuroscience Research Institute, The Ohio State University Wexner Medical CenterColumbus, OH, USA
| | - Juan Peng
- Center for Biostatistics, The Ohio State University Wexner Medical CenterColumbus, OH, USA
| | - Randy J Nelson
- Behavioral Neuroendocrinology Group, Department of Neuroscience, Neuroscience Research Institute, The Ohio State University Wexner Medical CenterColumbus, OH, USA
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Harrison EM, Carmack SA, Block CL, Sun J, Anagnostaras SG, Gorman MR. Circadian waveform bifurcation, but not phase-shifting, leaves cued fear memory intact. Physiol Behav 2017; 169:106-113. [DOI: 10.1016/j.physbeh.2016.11.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 10/26/2016] [Accepted: 11/21/2016] [Indexed: 11/25/2022]
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Lee ML, Katsuyama ÂM, Duge LS, Sriram C, Krushelnytskyy M, Kim JJ, de la Iglesia HO. Fragmentation of Rapid Eye Movement and Nonrapid Eye Movement Sleep without Total Sleep Loss Impairs Hippocampus-Dependent Fear Memory Consolidation. Sleep 2016; 39:2021-2031. [PMID: 27568801 DOI: 10.5665/sleep.6236] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 06/29/2016] [Indexed: 11/03/2022] Open
Abstract
STUDY OBJECTIVES Sleep is important for consolidation of hippocampus-dependent memories. It is hypothesized that the temporal sequence of nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep is critical for the weakening of nonadaptive memories and the subsequent transfer of memories temporarily stored in the hippocampus to more permanent memories in the neocortex. A great body of evidence supporting this hypothesis relies on behavioral, pharmacological, neural, and/or genetic manipulations that induce sleep deprivation or stage-specific sleep deprivation. METHODS We exploit an experimental model of circadian desynchrony in which intact animals are not deprived of any sleep stage but show fragmentation of REM and NREM sleep within nonfragmented sleep bouts. We test the hypothesis that the shortening of NREM and REM sleep durations post-training will impair memory consolidation irrespective of total sleep duration. RESULTS When circadian-desynchronized animals are trained in a hippocampus-dependent contextual fear-conditioning task they show normal short-term memory but impaired long-term memory consolidation. This impairment in memory consolidation is positively associated with the post-training fragmentation of REM and NREM sleep but is not significantly associated with the fragmentation of total sleep or the total amount of delta activity. We also show that the sleep stage fragmentation resulting from circadian desynchrony has no effect on hippocampus-dependent spatial memory and no effect on hippocampus-independent cued fear-conditioning memory. CONCLUSIONS Our findings in an intact animal model, in which sleep deprivation is not a confounding factor, support the hypothesis that the stereotypic sequence and duration of sleep stages play a specific role in long-term hippocampus-dependent fear memory consolidation.
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Affiliation(s)
- Michael L Lee
- Department of Biology, University of Washington, Seattle, WA.,Graduate Program in Neuroscience, University of Washington, Seattle, WA
| | | | - Leanne S Duge
- Department of Biology, University of Washington, Seattle, WA
| | - Chaitra Sriram
- Department of Biology, University of Washington, Seattle, WA
| | | | - Jeansok J Kim
- Graduate Program in Neuroscience, University of Washington, Seattle, WA.,Department of Psychology, University of Washington, Seattle WA
| | - Horacio O de la Iglesia
- Department of Biology, University of Washington, Seattle, WA.,Graduate Program in Neuroscience, University of Washington, Seattle, WA
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LeVault KR, Tischkau SA, Brewer GJ. Circadian Disruption Reveals a Correlation of an Oxidative GSH/GSSG Redox Shift with Learning and Impaired Memory in an Alzheimer's Disease Mouse Model. J Alzheimers Dis 2016; 49:301-16. [PMID: 26484899 DOI: 10.3233/jad-150026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
It is unclear whether pre-symptomatic Alzheimer's disease (AD) causes circadian disruption or whether circadian disruption accelerates AD pathogenesis. In order to examine the sensitivity of learning and memory to circadian disruption, we altered normal lighting phases by an 8 h shortening of the dark period every 3 days (jet lag) in the APPSwDI NOS2-/- model of AD (AD-Tg) at a young age (4-5 months), when memory is not yet affected compared to non-transgenic (non-Tg) mice. Analysis of activity in 12-12 h lighting or constant darkness showed only minor differences between AD-Tg and non-Tg mice. Jet lag greatly reduced activity in both genotypes during the normal dark time. Learning on the Morris water maze was significantly impaired only in the AD-Tg mice exposed to jet lag. However, memory 3 days after training was impaired in both genotypes. Jet lag caused a decrease of glutathione (GSH) levels that tended to be more pronounced in AD-Tg than in non-Tg brains and an associated increase in NADH levels in both genotypes. Lower brain GSH levels after jet lag correlated with poor performance on the maze. These data indicate that the combination of the environmental stress of circadian disruption together with latent stress of the mutant amyloid and NOS2 knockout contributes to cognitive deficits that correlate with lower GSH levels.
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Affiliation(s)
- Kelsey R LeVault
- Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School Medicine, Springfield, Illinois, USA
| | - Shelley A Tischkau
- Department of Pharmacology, Southern Illinois University School Medicine, Springfield, Illinois, USA
| | - Gregory J Brewer
- Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School Medicine, Springfield, Illinois, USA.,Department of Neurology, Southern Illinois University School Medicine, Springfield, Illinois, USA.,Institute for Memory Impairment and Neurological Disorders (MIND), Department of Biomedical Engineering, University of California Irvine, Irvine, California, USA (current)
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36
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Rozov SV, Zant JC, Gurevicius K, Porkka-Heiskanen T, Panula P. Altered Electroencephalographic Activity Associated with Changes in the Sleep-Wakefulness Cycle of C57BL/6J Mice in Response to a Photoperiod Shortening. Front Behav Neurosci 2016; 10:168. [PMID: 27630549 PMCID: PMC5005378 DOI: 10.3389/fnbeh.2016.00168] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 08/17/2016] [Indexed: 11/13/2022] Open
Abstract
AIM Under natural conditions diurnal rhythms of biological processes of the organism are synchronized with each other and to the environmental changes by means of the circadian system. Disturbances of the latter affect hormonal levels, sleep-wakefulness cycle and cognitive performance. To study mechanisms of such perturbations animal models subjected to artificial photoperiods are often used. The goal of current study was to understand the effects of circadian rhythm disruption, caused by a short light-dark cycle regime, on activity of the cerebral cortex in rodents. METHODS We used electroencephalogram to assess the distribution of vigilance states, perform spectral analysis, and estimate the homeostatic sleep drive. In addition, we analyzed spontaneous locomotion of C57BL/6J mice under symmetric, 22-, 21-, and 20-h-long light-dark cycles using video recording and tracking methods. RESULTS AND CONCLUSIONS We found that shortening of photoperiod caused a significant increase of slow wave activity during non-rapid eye movement sleep suggesting an elevation of sleep pressure under such conditions. While the rhythm of spontaneous locomotion was completely entrained by all light-dark cycles tested, periodic changes in the power of the θ- and γ-frequency ranges during wakefulness gradually disappeared under 22- and 21-h-long light-dark cycles. This was associated with a significant increase in the θ-γ phase-amplitude coupling during wakefulness. Our results thus provide deeper understanding of the mechanisms underlying the impairment of learning and memory retention, which is associated with disturbed circadian regulation.
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Affiliation(s)
- Stanislav V Rozov
- Department of Anatomy, Faculty of Medicine, Neuroscience Center, University of Helsinki Helsinki, Finland
| | - Janneke C Zant
- Department of Physiology, Faculty of Medicine, University of Helsinki Helsinki, Finland
| | - Kestutis Gurevicius
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland Kuopio, Finland
| | | | - Pertti Panula
- Department of Anatomy, Faculty of Medicine, Neuroscience Center, University of Helsinki Helsinki, Finland
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37
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Verwey M, Dhir S, Amir S. Circadian influences on dopamine circuits of the brain: regulation of striatal rhythms of clock gene expression and implications for psychopathology and disease. F1000Res 2016; 5. [PMID: 27635233 PMCID: PMC5007753 DOI: 10.12688/f1000research.9180.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/23/2016] [Indexed: 12/18/2022] Open
Abstract
Circadian clock proteins form an autoregulatory feedback loop that is central to the endogenous generation and transmission of daily rhythms in behavior and physiology. Increasingly, circadian rhythms in clock gene expression are being reported in diverse tissues and brain regions that lie outside of the suprachiasmatic nucleus (SCN), the master circadian clock in mammals. For many of these extra-SCN rhythms, however, the region-specific implications are still emerging. In order to gain important insights into the potential behavioral, physiological, and psychological relevance of these daily oscillations, researchers have begun to focus on describing the neurochemical, hormonal, metabolic, and epigenetic contributions to the regulation of these rhythms. This review will highlight important sites and sources of circadian control within dopaminergic and striatal circuitries of the brain and will discuss potential implications for psychopathology and disease
. For example, rhythms in clock gene expression in the dorsal striatum are sensitive to changes in dopamine release, which has potential implications for Parkinson’s disease and drug addiction. Rhythms in the ventral striatum and limbic forebrain are sensitive to psychological and physical stressors, which may have implications for major depressive disorder. Collectively, a rich circadian tapestry has emerged that forces us to expand traditional views and to reconsider the psychopathological, behavioral, and physiological importance of these region-specific rhythms in brain areas that are not immediately linked with the regulation of circadian rhythms.
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Affiliation(s)
- Michael Verwey
- Center for Studies in Behavioural Neurobiology, FRQS Groupe de Recherche en Neurobiologie Comportementale, Concorida University, Montreal, Quebec, Canada
| | | | - Shimon Amir
- Center for Studies in Behavioural Neurobiology, FRQS Groupe de Recherche en Neurobiologie Comportementale, Concorida University, Montreal, Quebec, Canada
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38
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Deibel SH, Zelinski EL, Keeley RJ, Kovalchuk O, McDonald RJ. Epigenetic alterations in the suprachiasmatic nucleus and hippocampus contribute to age-related cognitive decline. Oncotarget 2016; 6:23181-203. [PMID: 26252151 PMCID: PMC4695111 DOI: 10.18632/oncotarget.4036] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 12/31/1969] [Indexed: 12/16/2022] Open
Abstract
Circadian rhythm dysfunction and cognitive decline, specifically memory loss, frequently accompany natural aging. Circadian rhythms and memory are intertwined, as circadian rhythms influence memory formation and recall in young and old rodents. Although, the precise relationship between circadian rhythms and memory is still largely unknown, it is hypothesized that circadian rhythm disruption, which occurs during aging, contributes to age-associated cognitive decline, specifically memory loss. While there are a variety of mechanisms that could mediate this effect, changes in the epigenome that occur during aging has been proposed as a potential candidate. Interestingly, epigenetic mechanisms, such as DNA methylation and sirtuin1 (SIRT1) are necessary for both circadian rhythms and memory. During aging, similar alterations of epigenetic mechanisms occur in the suprachiasmatic nucleus (SCN) and hippocampus, which are necessary for circadian rhythm generation and memory, respectively. Recently, circadian rhythms have been linked to epigenetic function in the hippocampus, as some of these epigenetic mechanisms oscillate in the hippocampus and are disrupted by clock gene deletion. The current paper will review how circadian rhythms and memory change with age, and will suggest how epigenetic changes in these processes might contribute to age-related cognitive decline.
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Affiliation(s)
- Scott H Deibel
- Canadian Centre for Behavioural Neuroscience, Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Erin L Zelinski
- Canadian Centre for Behavioural Neuroscience, Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Robin J Keeley
- Canadian Centre for Behavioural Neuroscience, Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Olga Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, Canada
| | - Robert J McDonald
- Canadian Centre for Behavioural Neuroscience, Department of Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
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Rizzo SJS. Repetitive Behavioral Assessments for Compound Screening in Mouse Models of Autism Spectrum Disorders. Methods Mol Biol 2016; 1438:293-310. [PMID: 27150097 DOI: 10.1007/978-1-4939-3661-8_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Treatments for repetitive behaviors in Autism Spectrum Disorders (ASD) and other neurodevelopmental disorders remain an unmet medical need. Mouse models are highly valuable tools for investigating the underlying pathophysiology, genetics, and neurocircuitry of ASD, and can also be characterized for ASD-related phenotypes including repetitive behaviors and stereotypies. This chapter describes methods that can be employed for the assessment of repetitive behavior phenotypes and the evaluation of the ability of test compounds to attenuate repetitive behaviors in mouse models of ASD.
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Loh DH, Jami SA, Flores RE, Truong D, Ghiani CA, O'Dell TJ, Colwell CS. Misaligned feeding impairs memories. eLife 2015; 4. [PMID: 26652002 PMCID: PMC4729691 DOI: 10.7554/elife.09460] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 11/19/2015] [Indexed: 01/23/2023] Open
Abstract
Robust sleep/wake rhythms are important for health and cognitive function. Unfortunately, many people are living in an environment where their circadian system is challenged by inappropriate meal- or work-times. Here we scheduled food access to the sleep time and examined the impact on learning and memory in mice. Under these conditions, we demonstrate that the molecular clock in the master pacemaker, the suprachiasmatic nucleus (SCN), is unaltered while the molecular clock in the hippocampus is synchronized by the timing of food availability. This chronic circadian misalignment causes reduced hippocampal long term potentiation and total CREB expression. Importantly this mis-timed feeding resulted in dramatic deficits in hippocampal-dependent learning and memory. Our findings suggest that the timing of meals have far-reaching effects on hippocampal physiology and learned behaviour. DOI:http://dx.doi.org/10.7554/eLife.09460.001 Many processes within the body follow an approximately 24-hour cycle. In addition to patterns of sleep and wakefulness, such circadian rhythms help to regulate body temperature, blood pressure and hormone levels. They also affect when we feel hungry, when our muscles work most efficiently, and when we are mentally at our sharpest. A region of the brain called the suprachiasmatic nucleus (SCN) generates and maintains circadian rhythms, and thus acts as the body’s master clock. Daily exposure to light keeps the SCN synchronized with the 24-hour day/night cycle. However, most organs, from the heart to the pancreas, also possess their own clocks, which help to regulate organ-specific processes. These secondary clocks normally operate in synchrony with the SCN. Exposure to light has long been known to influence circadian rhythms. However, more recent evidence suggests that the timing of meals may also affect circadian clocks, particularly those within the digestive system. Loh et al. therefore decided to investigate whether eating outside normal waking hours would also affect other key physiological processes, specifically the cognitive processes of learning and memory. Mice normally consume most of their food after sunset. Loh et al. showed that rodents that were instead fed during the day performed less well on cognitive tests than other mice who received the same food at night. The daytime-fed mice showed changes in a region of the brain called the hippocampus, which supports learning and memory. In particular, daytime feeding changed the timing of the secondary circadian clock within the hippocampus, although it had no effect on the master clock in the SCN. Loh et al. therefore suggest that the misalignment of these circadian clocks impairs cognition. Further experiments are needed to determine whether a similar relationship exists between the timing of meals and cognitive performance in humans. If so, these findings will have implications for the many individuals whose mealtimes, for work or social reasons, are out of synchrony with their body clocks. DOI:http://dx.doi.org/10.7554/eLife.09460.002
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Affiliation(s)
- Dawn H Loh
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States.,UCLA Integrative Center for Learning and Memory, University of California, Los Angeles, Los Angeles, United States
| | - Shekib A Jami
- UCLA Integrative Center for Learning and Memory, University of California, Los Angeles, Los Angeles, United States.,Molecular, Cellular, and Integrative Physiology PhD Program, University of California, Los Angeles, Los Angeles, United States
| | - Richard E Flores
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Danny Truong
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Cristina A Ghiani
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States.,Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Thomas J O'Dell
- UCLA Integrative Center for Learning and Memory, University of California, Los Angeles, Los Angeles, United States.,Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Christopher S Colwell
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States.,UCLA Integrative Center for Learning and Memory, University of California, Los Angeles, Los Angeles, United States
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Krishnan HC, Lyons LC. Synchrony and desynchrony in circadian clocks: impacts on learning and memory. ACTA ACUST UNITED AC 2015; 22:426-37. [PMID: 26286653 PMCID: PMC4561405 DOI: 10.1101/lm.038877.115] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 06/29/2015] [Indexed: 12/11/2022]
Abstract
Circadian clocks evolved under conditions of environmental variation, primarily alternating light dark cycles, to enable organisms to anticipate daily environmental events and coordinate metabolic, physiological, and behavioral activities. However, modern lifestyle and advances in technology have increased the percentage of individuals working in phases misaligned with natural circadian activity rhythms. Endogenous circadian oscillators modulate alertness, the acquisition of learning, memory formation, and the recall of memory with examples of circadian modulation of memory observed across phyla from invertebrates to humans. Cognitive performance and memory are significantly diminished when occurring out of phase with natural circadian rhythms. Disruptions in circadian regulation can lead to impairment in the formation of memories and manifestation of other cognitive deficits. This review explores the types of interactions through which the circadian clock modulates cognition, highlights recent progress in identifying mechanistic interactions between the circadian system and the processes involved in memory formation, and outlines methods used to remediate circadian perturbations and reinforce circadian adaptation.
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Affiliation(s)
- Harini C Krishnan
- Department of Biological Science, Program in Neuroscience, Florida State University, Tallahassee, Florida 32306, USA
| | - Lisa C Lyons
- Department of Biological Science, Program in Neuroscience, Florida State University, Tallahassee, Florida 32306, USA
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Ruby NF, Patton DF, Bane S, Looi D, Heller HC. Reentrainment Impairs Spatial Working Memory until Both Activity Onset and Offset Reentrain. J Biol Rhythms 2015. [PMID: 26224657 DOI: 10.1177/0748730415596254] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Compression of the active phase (α) during reentrainment to phase-shifted light-dark (LD) cycles is a common feature of circadian systems, but its functional consequences have not been investigated. This study tested whether α compression in Siberian hamsters (Phodopus sungorus) impaired their spatial working memory as assessed by spontaneous alternation (SA) behavior in a T-maze. Animals were exposed to a 1- or 3-h phase delay of the LD cycle (16 h light/8 h dark). SA behavior was tested at 4 multiday intervals after the phase shift, and α was quantified for those days. All animals failed at the SA task while α was decompressing but recovered spatial memory ability once α returned to baseline levels. A second experiment exposed hamsters to a 2-h light pulse either early or late at night to compress α without phase-shifting the LD cycle. SA behavior was impaired until α decompressed to baseline levels. In a third experiment, α was compressed by changing photoperiod (LD 16:8, 18:6, 20:4) to see if absolute differences in α were related to spatial memory ability. Animals performed the SA task successfully in all 3 photoperiods. These data show that the dynamic process of α compression and decompression impairs spatial working memory and suggests that α modulation is a potential biomarker for assessing the impact of transmeridian flight or shift work on memory.
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Affiliation(s)
- Norman F Ruby
- Biology Department, Stanford University, Stanford, California
| | - Danica F Patton
- Biology Department, Stanford University, Stanford, California
| | - Shalmali Bane
- Biology Department, Stanford University, Stanford, California
| | - David Looi
- Biology Department, Stanford University, Stanford, California
| | - H Craig Heller
- Biology Department, Stanford University, Stanford, California
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Alves-Simoes M, Coleman G, Canal MM. Effects of type of light on mouse circadian behaviour and stress levels. Lab Anim 2015; 50:21-9. [PMID: 25979911 DOI: 10.1177/0023677215588052] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Light is the principal synchronizing environmental factor for the biological clock. Light quantity (intensity), and light quality (type of light source) can have different effects. The aim of this study was to determine the effects of the type of light experienced from the time of birth on mouse growth, circadian behaviour and stress levels. We raised pigmented and albino mice under 24 h light-dark cycles of either fluorescent or white light-emitting diode (LED) light source during the suckling stage, and the animals were then exposed to various light environments after weaning and their growth rate, locomotor activity and plasma corticosterone concentration were measured. We found that the type of light the animals were exposed to did not affect the animals' growth rates or stress levels. However, we observed significant effects on the expression of the locomotor activity rhythm under low contrast light-dark cycles in pigmented mice, and under constant light in both albino and pigmented mice. These results highlight the importance of environmental light quality (light source) on circadian behavioural rhythms, and the need for close monitoring of light environments in animal facilities.
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Affiliation(s)
| | - Georgia Coleman
- Faculty of Life Sciences, University of Manchester, Manchester, UK
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Woodruff ER, Greenwood BN, Chun LE, Fardi S, Hinds LR, Spencer RL. Adrenal-dependent diurnal modulation of conditioned fear extinction learning. Behav Brain Res 2015; 286:249-55. [PMID: 25746455 DOI: 10.1016/j.bbr.2015.03.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 03/01/2015] [Accepted: 03/02/2015] [Indexed: 12/23/2022]
Abstract
Post traumatic stress disorder (PTSD) is associated with altered conditioned fear extinction expression and impaired circadian function including dysregulation of glucocorticoid hormone secretion. We examined in adult male rats the relationship between conditioned fear extinction learning, circadian phase, and endogenous glucocorticoids (CORT). Rats maintained on a 12h light:dark cycle were trained and tested across 3 separate daily sessions (conditioned fear acquisition and 2 extinction sessions) that were administered during either the rats' active or inactive circadian phase. In an initial experiment we found that rats at both circadian phases acquired and extinguished auditory cue conditioned fear to a similar degree in the first extinction session. However, rats trained and tested at zeitgeber time-16 (ZT16) (active phase) showed enhanced extinction memory expression during the second extinction session compared to rats trained and tested at ZT4 (inactive phase). In a follow-up experiment, adrenalectomized (ADX) or sham surgery rats were similarly trained and tested across 3 separate daily sessions at either ZT4 or ZT16. ADX had no effect on conditioned fear acquisition or conditioned fear memory. Sham ADX rats trained and tested at ZT16 exhibited better extinction learning across the two extinction sessions compared to all other groups of rats. These results indicate that conditioned fear extinction learning is modulated by time of day, and this diurnal modulation requires the presence of adrenal hormones. These results support an important role of CORT-dependent circadian processes in regulating conditioned fear extinction learning, which may be capitalized upon to optimize effective treatment of PTSD.
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Affiliation(s)
- Elizabeth R Woodruff
- Department of Psychology and Neuroscience, University of Colorado, UCB 345, Boulder, CO 80309, USA.
| | - Benjamin N Greenwood
- Department of Integrated Physiology, University of Colorado, UCB 354, Boulder, CO 80309, USA.
| | - Lauren E Chun
- Department of Psychology and Neuroscience, University of Colorado, UCB 345, Boulder, CO 80309, USA.
| | - Sara Fardi
- Department of Psychology and Neuroscience, University of Colorado, UCB 345, Boulder, CO 80309, USA.
| | - Laura R Hinds
- Department of Psychology and Neuroscience, University of Colorado, UCB 345, Boulder, CO 80309, USA.
| | - Robert L Spencer
- Department of Psychology and Neuroscience, University of Colorado, UCB 345, Boulder, CO 80309, USA.
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Deng Z, Lubinski AJ, Page TL. Zeta inhibitory peptide (ZIP) erases long-term memories in a cockroach. Neurobiol Learn Mem 2014; 118:89-95. [PMID: 25434819 DOI: 10.1016/j.nlm.2014.11.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 11/11/2014] [Accepted: 11/21/2014] [Indexed: 12/20/2022]
Abstract
Recent efforts to identify the molecules that are involved in the maintenance of long-term memories in mammals have focused attention on atypical isoforms of protein kinase C (PKC). Inhibition of these kinases by either the general PKC inhibitor, chelerythrine, or the more specific inhibitor, zeta inhibitory peptide (ZIP), can abolish both long-term potentiation in the hippocampus and as well as spatial, fear, appetitive, and sensorimotor memories. These inhibitors can also abolish long-term facilitation and long-term sensitization in the mollusk Aplysia californica. We have extended these results to an insect, the cockroach Leucophaea maderae. We show that systemic injections of either chelerythrine or ZIP erase long-term olfactory memories in the cockroach, but have no effect on memory acquisition during conditioning. We also show that inhibition of either protein kinase A (PKA) or protein synthesis can block memory acquisition but neither has an effect on the memory once it is formed. The results suggest that sustaining memories in insects requires the persistent activity of one or more isoforms of PKC and point to a strong evolutionary conservation of the molecular mechanisms that underlie the persistence of long-term memories in the central nervous system.
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Affiliation(s)
- Zhouheng Deng
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, United States
| | - Alexander J Lubinski
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, United States
| | - Terry L Page
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, United States.
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46
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Landgraf D, McCarthy MJ, Welsh DK. Circadian clock and stress interactions in the molecular biology of psychiatric disorders. Curr Psychiatry Rep 2014; 16:483. [PMID: 25135782 DOI: 10.1007/s11920-014-0483-7] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Many psychiatric disorders are characterized by circadian rhythm abnormalities, including disturbed sleep/wake cycles, changes in locomotor activity, and abnormal endocrine function. Animal models with mutations in circadian "clock genes" commonly show disturbances in reward processing, locomotor activity and novelty seeking behaviors, further supporting the idea of a connection between the circadian clock and psychiatric disorders. However, if circadian clock dysfunction is a common risk factor for multiple psychiatric disorders, it is unknown if and how these putative clock abnormalities could be expressed differently, and contribute to multiple, distinct phenotypes. One possible explanation is that the circadian clock modulates the biological responses to stressful environmental factors that vary with an individual's experience. It is known that the circadian clock and the stress response systems are closely related: Circadian clock genes regulate the physiological sensitivity to and rhythmic release of glucocorticoids (GC). In turn, GCs have reciprocal effects on the clock. Since stressful life events or increased vulnerability to stress are risk factors for multiple psychiatric disorders, including post-traumatic stress disorder (PTSD), attention deficit hyperactivity disorder (ADHD), bipolar disorder (BD), major depressive disorder (MDD), alcohol use disorder (AUD) and schizophrenia (SCZ), we propose that modulation of the stress response is a common mechanism by which circadian clock genes affect these illnesses. Presently, we review how molecular components of the circadian clock may contribute to these six psychiatric disorders, and present the hypothesis that modulation of the stress response may constitute a common mechanism by which the circadian clock affects multiple psychiatric disorders.
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Affiliation(s)
- Dominic Landgraf
- Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
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47
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Jung SH, Park JM, Moon E, Chung YI, Lee BD, Lee YM, Kim JH, Kim SY, Jeong HJ. Delay in the recovery of normal sleep-wake cycle after disruption of the light-dark cycle in mice: a bipolar disorder-prone animal model? Psychiatry Investig 2014; 11:487-91. [PMID: 25395982 PMCID: PMC4225215 DOI: 10.4306/pi.2014.11.4.487] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 08/16/2013] [Accepted: 09/30/2013] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVE Disruption of the circadian rhythm is known as a provoking factor for manic episodes. Individual differences exist in the recovery rate from disruption in the general population. To develop a screening method to detect individuals vulnerable to bipolar disorder, the authors observed the relationship between the recovery of the normal sleep-wake cycle after switching the light-dark (LD) cycle and quinpirole-induced hyperactivity in mice. METHODS Sixteen male mice (age of 5 weeks, weight 28-29 gm) were subjected to a circadian rhythm disruption protocol. Sleep-wake behaviors were checked every 5 min for a total duration of 15 days, i.e., 2 days of baseline observations, 3 days of LD cycle changes, and 10 days of recovery. During the dark cycle on the 16th experimental day, their general locomotor activities were measured in an open field for 120 minutes after an injection of quinpirole (0.5 mg/kg, s.c.). RESULTS The individual differences in the recovery rate of the baseline sleep-wake cycle were noted after 3 days of switching the LD cycle. Fifty percent (n=8) of the mice returned to the baseline cycle within 6 days after normalizing the LD cycle (early recovery group). The locomotor activities of mice that failed to recover within 6 days (delayed recovery group) were significantly higher (mean rank=12.25) than those of the early recovery group (mean rank=4.75, u=62.0, p=0.001, Mann-Whitney U test). CONCLUSION Given that the quinpirole-induced hyperactivity is an animal model of bipolar disorder, our results suggest individuals who have difficulties in recovery from circadian rhythm disruption may be vulnerable to bipolar disorder.
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Affiliation(s)
- Sun Hwa Jung
- Department of Psychiatry, Pusan National University Hospital, Busan, Republic of Korea
| | - Je-Min Park
- Department of Psychiatry, Pusan National University School of Medicine, Busan, Republic of Korea
| | - Eunsoo Moon
- Department of Psychiatry, Pusan National University Hospital, Busan, Republic of Korea
| | - Young In Chung
- Department of Psychiatry, Pusan National University School of Medicine, Busan, Republic of Korea
| | - Byung Dae Lee
- Department of Psychiatry, Pusan National University Hospital, Busan, Republic of Korea
| | - Young Min Lee
- Department of Psychiatry, Pusan National University Hospital, Busan, Republic of Korea
| | - Ji Hoon Kim
- Department of Psychiatry, Pusan National University School of Medicine, Busan, Republic of Korea
| | - Soo Yeon Kim
- Department of Psychiatry, Pusan National University Hospital, Busan, Republic of Korea
| | - Hee Jeong Jeong
- Department of Psychiatry, Pusan National University Hospital, Busan, Republic of Korea
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48
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Li H, Li X, Smerin SE, Zhang L, Jia M, Xing G, Su YA, Wen J, Benedek D, Ursano R. Mitochondrial Gene Expression Profiles and Metabolic Pathways in the Amygdala Associated with Exaggerated Fear in an Animal Model of PTSD. Front Neurol 2014; 5:164. [PMID: 25295026 PMCID: PMC4172054 DOI: 10.3389/fneur.2014.00164] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 08/15/2014] [Indexed: 12/19/2022] Open
Abstract
The metabolic mechanisms underlying the development of exaggerated fear in post-traumatic stress disorder (PTSD) are not well defined. In the present study, alteration in the expression of genes associated with mitochondrial function in the amygdala of an animal model of PTSD was determined. Amygdala tissue samples were excised from 10 non-stressed control rats and 10 stressed rats, 14 days post-stress treatment. Total RNA was isolated, cDNA was synthesized, and gene expression levels were determined using a cDNA microarray. During the development of the exaggerated fear associated with PTSD, 48 genes were found to be significantly upregulated and 37 were significantly downregulated in the amygdala complex based on stringent criteria (p < 0.01). Ingenuity pathway analysis revealed up- or downregulation in the amygdala complex of four signaling networks – one associated with inflammatory and apoptotic pathways, one with immune mediators and metabolism, one with transcriptional factors, and one with chromatin remodeling. Thus, informatics of a neuronal gene array allowed us to determine the expression profile of mitochondrial genes in the amygdala complex of an animal model of PTSD. The result is a further understanding of the metabolic and neuronal signaling mechanisms associated with delayed and exaggerated fear.
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Affiliation(s)
- He Li
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Xin Li
- Department of Biostatistics, Bioinformatics, and Biomathematics, Georgetown University Medical Center , Washington, DC , USA
| | - Stanley E Smerin
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Lei Zhang
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Min Jia
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Guoqiang Xing
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Yan A Su
- Department of Gene and Protein Biomarkers, GenProMarkers , Rockville, MD , USA
| | - Jillian Wen
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - David Benedek
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Robert Ursano
- Department of Psychiatry, Center for the Study of Traumatic Stress, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
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49
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Michel M, Lyons LC. Unraveling the complexities of circadian and sleep interactions with memory formation through invertebrate research. Front Syst Neurosci 2014; 8:133. [PMID: 25136297 PMCID: PMC4120776 DOI: 10.3389/fnsys.2014.00133] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 07/07/2014] [Indexed: 12/14/2022] Open
Abstract
Across phylogeny, the endogenous biological clock has been recognized as providing adaptive advantages to organisms through coordination of physiological and behavioral processes. Recent research has emphasized the role of circadian modulation of memory in generating peaks and troughs in cognitive performance. The circadian clock along with homeostatic processes also regulates sleep, which itself impacts the formation and consolidation of memory. Thus, the circadian clock, sleep and memory form a triad with ongoing dynamic interactions. With technological advances and the development of a global 24/7 society, understanding the mechanisms underlying these connections becomes pivotal for development of therapeutic treatments for memory disorders and to address issues in cognitive performance arising from non-traditional work schedules. Invertebrate models, such as Drosophila melanogaster and the mollusks Aplysia and Lymnaea, have proven invaluable tools for identification of highly conserved molecular processes in memory. Recent research from invertebrate systems has outlined the influence of sleep and the circadian clock upon synaptic plasticity. In this review, we discuss the effects of the circadian clock and sleep on memory formation in invertebrates drawing attention to the potential of in vivo and in vitro approaches that harness the power of simple invertebrate systems to correlate individual cellular processes with complex behaviors. In conclusion, this review highlights how studies in invertebrates with relatively simple nervous systems can provide mechanistic insights into corresponding behaviors in higher organisms and can be used to outline possible therapeutic options to guide further targeted inquiry.
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Affiliation(s)
- Maximilian Michel
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine Nashville, TN, USA
| | - Lisa C Lyons
- Department of Biological Science, Program in Neuroscience, Florida State University Tallahassee, FL, USA
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50
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Wardlaw SM, Phan TX, Saraf A, Chen X, Storm DR. Genetic disruption of the core circadian clock impairs hippocampus-dependent memory. Learn Mem 2014; 21:417-23. [PMID: 25034823 PMCID: PMC4105720 DOI: 10.1101/lm.035451.114] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 06/11/2014] [Indexed: 11/25/2022]
Abstract
Perturbing the circadian system by electrolytically lesioning the suprachiasmatic nucleus (SCN) or varying the environmental light:dark schedule impairs memory, suggesting that memory depends on the circadian system. We used a genetic approach to evaluate the role of the molecular clock in memory. Bmal1-/- mice, which are arrhythmic under constant conditions, were examined for hippocampus-dependent memory, LTP at the Schaffer-collateral synapse, and signal transduction activity in the hippocampus. Bmal1-/- mice exhibit impaired contextual fear and spatial memory. Furthermore, LTP in hippocampal slices from Bmal1-/- mice is also significantly decreased relative to that from wild-type mice. Activation of Erk1,2 MAP kinase (MAPK) during training for contextual fear memory and diurnal oscillation of MAPK activity and cAMP in the hippocampus is also lost in Bmal1-/- mice, suggesting that the memory defects are due to reduction of the memory consolidation pathway in the hippocampus. We conclude that critical signaling events in the hippocampus required for memory depend on BMAL1.
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Affiliation(s)
- Sarah M Wardlaw
- Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington 98195-7750, USA
| | - Trongha X Phan
- Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington 98195-7750, USA
| | - Amit Saraf
- Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington 98195-7750, USA
| | - Xuanmao Chen
- Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington 98195-7750, USA
| | - Daniel R Storm
- Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington 98195-7750, USA
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