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Pang X, Chen L, Xu G. New Awareness of the Interplay Between the Gut Microbiota and Circadian Rhythms. Pol J Microbiol 2023; 72:355-363. [PMID: 38095865 PMCID: PMC10725168 DOI: 10.33073/pjm-2023-046] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 10/27/2023] [Indexed: 12/17/2023] Open
Abstract
Circadian rhythms influence various aspects of the biology and physiology of the host, such as food intake and sleep/wake cycles. In recent years, an increasing amount of genetic and epidemiological data has shown that the light/dark cycle is the main cue that regulates circadian rhythms. Other factors, including sleep/wake cycles and food intake, have necessary effects on the composition and rhythms of the gut microbiota. Interestingly, the gut microbiota can affect the circadian rhythm of hosts in turn through contact-dependent and contact-independent mechanisms. Furthermore, the gut microbiota has been shown to regulate the sleep/wake cycles through gut-brain-microbiota interaction. In addition to diabetes, the gut microbiota can also intervene in the progression of neuro- degenerative diseases through the gut-brain-microbiota interaction, and also in other diseases such as hypertension and rheumatoid arthritis, where it is thought to have a spare therapeutic potential. Even though fecal microbiota transplantation has good potential for treating many diseases, the risk of spreading intestinal pathogens should not be ignored.
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Affiliation(s)
- Xiaoxiao Pang
- Department of Clinical Laboratory, The Affiliated Zhangjiagang Hospital of Soochow University, Suzhou, China
| | - Long Chen
- Department of Clinical Laboratory, The Affiliated Zhangjiagang Hospital of Soochow University, Suzhou, China
| | - Guoxin Xu
- Department of Clinical Laboratory, The Affiliated Zhangjiagang Hospital of Soochow University, Suzhou, China
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2
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Radahmadi M, Salehifard K, Reisi P. In vivo synaptic potency, short-term and long-term plasticity at the hippocampal Schaffer collateral-CA1 synapses: Role of different light-dark cycles in male rats. Brain Res 2023; 1817:148514. [PMID: 37499734 DOI: 10.1016/j.brainres.2023.148514] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 07/29/2023]
Abstract
The changes in the light-dark(L/D) cycle could modify cellular mechanisms in some brain regions. The present study compared the effects of various L/D cycles on invivo synaptic potency, short-term and long-term plasticity in the hippocampal CA1 area, adrenal glands weight(AGWs), corticosterone (CORT) levels, and body weight differences(BWD) in male rats. Male rats were assigned into different L/D cycle groups: L4/D20, L8/D16, L12/D12(control), L16/D8, and L20/D4. The slope, amplitude, and the area under curve(AUC) related to the field excitatory postsynaptic potentials(fEPSPs) were assessed, using the input-output(I/O) functions, paired-pulse(PP) responses at different interpulse intervals, and after the induction of long-term potentiation(LTP) in the hippocampal CA1 area. Also, the CORT levels, AGWs, and BWDs were measured in all groups. The slope, amplitude, and AUC of fEPSP in the I/O functions, all three phases of PP, before and after the LTP induction, were significantly decreased in all experimental groups, especially in the L20/D4 and L4/D20 groups. As such, the CORT levels and AGWs were significantly increased in all experimental groups, especially in the L20/D4 group. Overall, the uncommon L/D cycles (minimum and particularly maximum durations of light) significantly reduced the cellular mechanism of learning and memory. Also, downtrends were observed in synaptic potency, as well as short-term and long-term plasticity. The changes in PP with high interpulse intervals, or activity of GABAB receptors, were more significant than the changes in other PP phases with different L/D durations. Additionally, the CORT levels, adrenal glands, and body weight gain occurred time-independently concerning different L/D lengths.
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Affiliation(s)
- Maryam Radahmadi
- Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Kowsar Salehifard
- Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Parham Reisi
- Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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3
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Roberts BL, Karatsoreos IN. Circadian desynchronization disrupts physiological rhythms of prefrontal cortex pyramidal neurons in mice. Sci Rep 2023; 13:9181. [PMID: 37280307 DOI: 10.1038/s41598-023-35898-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 05/25/2023] [Indexed: 06/08/2023] Open
Abstract
Disruption of circadian rhythms, such as shift work and jet lag, are associated with negative physiological and behavioral outcomes, including changes in affective state, learning and memory, and cognitive function. The prefrontal cortex (PFC) is heavily involved in all of these processes. Many PFC-associated behaviors are time-of-day dependent, and disruption of daily rhythms negatively impacts these behavioral outputs. Yet how disruption of daily rhythms impacts the fundamental function of PFC neurons, and the mechanism(s) by which this occurs, remains unknown. Using a mouse model, we demonstrate that the activity and action potential dynamics of prelimbic PFC neurons are regulated by time-of-day in a sex specific manner. Further, we show that postsynaptic K+ channels play a central role in physiological rhythms, suggesting an intrinsic gating mechanism mediating physiological activity. Finally, we demonstrate that environmental circadian desynchronization alters the intrinsic functioning of these neurons independent of time-of-day. These key discoveries demonstrate that daily rhythms contribute to the mechanisms underlying the essential physiology of PFC circuits and provide potential mechanisms by which circadian disruption may impact the fundamental properties of neurons.
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Affiliation(s)
- Brandon L Roberts
- Neuroscience and Behavior Program, and Department of Psychological and Brain Sciences, University of Massachusetts Amherst, Tobin Hall, 135 Hicks Way, Amherst, MA, 01003S, USA
| | - Ilia N Karatsoreos
- Neuroscience and Behavior Program, and Department of Psychological and Brain Sciences, University of Massachusetts Amherst, Tobin Hall, 135 Hicks Way, Amherst, MA, 01003S, USA.
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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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Cheng WY, Ho YS, Chang RCC. Linking circadian rhythms to microbiome-gut-brain axis in aging-associated neurodegenerative diseases. Ageing Res Rev 2022; 78:101620. [PMID: 35405323 DOI: 10.1016/j.arr.2022.101620] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 03/13/2022] [Accepted: 04/06/2022] [Indexed: 12/12/2022]
Abstract
Emerging evidence suggests that both disruption of circadian rhythms and gut dysbiosis are closely related to aging-associated neurodegenerative diseases. Over the last decade, the microbiota-gut-brain axis has been an emerging field and revolutionized studies in pathology, diagnosis, and treatment of neurological disorders. Crosstalk between the brain and gut microbiota can be accomplished via the endocrine, immune, and nervous system. Recent studies have shown that the composition and diurnal oscillation of gut microbiota are influenced by host circadian rhythms. This provides a new perspective for investigating the microbiome-gut-brain axis. We aim to review current understanding and research on the dynamic interaction between circadian rhythms and the microbiome-gut-brain axis. Furthermore, we will address the possible neurodegenerative disease contribution through circadian rhythms and microbiome-gut-brain axis crosstalk.
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Affiliation(s)
- Wai-Yin Cheng
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Yuen-Shan Ho
- School of Nursing, Faculty of Health and Social Sciences, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong Special Administrative Region.
| | - Raymond Chuen-Chung Chang
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region; State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong Special Administrative Region.
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Steiger A, Farfan J, Fisher N, Heller HC, Fernandez FX, Ruby NF. Reversible Suppression of Fear Memory Recall by Transient Circadian Arrhythmia. Front Integr Neurosci 2022; 16:900620. [PMID: 35694186 PMCID: PMC9184752 DOI: 10.3389/fnint.2022.900620] [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: 03/21/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022] Open
Abstract
We tested the hypothesis that a temporary period of circadian arrhythmia would transiently impair recall of an aversive memory in Siberian hamsters (Phodopus sungorus). Unlike mice or rats, circadian arrhythmia is easily induced in this species by a one-time manipulation of their ambient lighting [i.e., the disruptive phase shift (DPS) protocol]. Hamsters were conditioned to associate footshocks with a shock chamber (context) and with a predictive auditory tone (cue), and then exposed to the DPS protocol. Following DPS, animals either became arrhythmic (ARR), reentrained to the light-dark cycle (ENT), or became arrhythmic for < 14 days before their circadian locomotor rhythms spontaneously recovered and reentrained (ARR-ENT). Tests for contextual memory showed that freezing was decreased 9–10 days post-DPS when both ARR and ARR-ENT groups were arrhythmic. Once ARR-ENT animals reentrained (day 41), however, freezing was elevated back to Pre-DPS levels and did not differ from those observed in ENT hamsters. ENT animals maintained high levels of freezing at both time points, whereas, freezing remained low in ARR hamsters. In contrast to contextual responses, cued responses were unaffected by circadian arrhythmia; all three groups exhibited elevated levels of freezing in response to the tones. The differential impact of circadian arrhythmia on contextual versus cued associative memory suggests that arrhythmia preferentially impacts memory processes that depend on the hippocampus.
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Affiliation(s)
- Athreya Steiger
- Department of Biology, Stanford University, Stanford, CA, United States
| | - Julia Farfan
- Department of Biology, Stanford University, Stanford, CA, United States
| | - Nathan Fisher
- Department of Biology, Stanford University, Stanford, CA, United States
| | - H. Craig Heller
- Department of Biology, Stanford University, Stanford, CA, United States
| | - Fabian-Xosé Fernandez
- Department of Psychology, University of Arizona College of Science, Tucson, AZ, United States
| | - Norman F. Ruby
- Department of Biology, Stanford University, Stanford, CA, United States
- *Correspondence: Norman F. Ruby,
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Hoyt KR, Obrietan K. Circadian clocks, cognition, and Alzheimer's disease: synaptic mechanisms, signaling effectors, and chronotherapeutics. Mol Neurodegener 2022; 17:35. [PMID: 35525980 PMCID: PMC9078023 DOI: 10.1186/s13024-022-00537-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 04/08/2022] [Indexed: 12/20/2022] Open
Abstract
Modulation of basic biochemical and physiological processes by the circadian timing system is now recognized as a fundamental feature of all mammalian organ systems. Within the central nervous system, these clock-modulating effects are reflected in some of the most complex behavioral states including learning, memory, and mood. How the clock shapes these behavioral processes is only now beginning to be realized. In this review we describe recent findings regarding the complex set of cellular signaling events, including kinase pathways, gene networks, and synaptic circuits that are under the influence of the clock timing system and how this, in turn, shapes cognitive capacity over the circadian cycle. Further, we discuss the functional roles of the master circadian clock located in the suprachiasmatic nucleus, and peripheral oscillator populations within cortical and limbic circuits, in the gating of synaptic plasticity and memory over the circadian cycle. These findings are then used as the basis to discuss the connection between clock dysregulation and cognitive impairments resulting from Alzheimer's disease (AD). In addition, we discuss the conceptually novel idea that in AD, there is a selective disruption of circadian timing within cortical and limbic circuits, and that it is the disruption/desynchronization of these regions from the phase-entraining effects of the SCN that underlies aspects of the early- and mid-stage cognitive deficits in AD. Further, we discuss the prospect that the disruption of circadian timing in AD could produce a self-reinforcing feedback loop, where disruption of timing accelerates AD pathogenesis (e.g., amyloid deposition, oxidative stress and cell death) that in turn leads to a further disruption of the circadian timing system. Lastly, we address potential therapeutic approaches that could be used to strengthen cellular timing networks and, in turn, how these approaches could be used to improve cognitive capacity in Alzheimer's patients.
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Affiliation(s)
- Kari R Hoyt
- Division of Pharmaceutics and Pharmacology, Ohio State University, 412 Riffe Building, 12th Ave, Columbus, OH, 43210, USA.
| | - Karl Obrietan
- Department of Neuroscience, Ohio State University, Graves Hall, 333 W. 10th Ave, Columbus, OH, 43210, USA.
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Liu D, Li J, Lin H, Lorsung E, Le N, Singla R, Mishra A, Fukunaga R, Cao R. Circadian activities of the brain MNK-eIF4E signalling axis contribute to diurnal rhythms of some cognitive functions. Eur J Neurosci 2022; 56:3553-3569. [PMID: 35481869 PMCID: PMC9477079 DOI: 10.1111/ejn.15678] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 03/28/2022] [Accepted: 04/03/2022] [Indexed: 12/18/2022]
Abstract
Although it is well recognized that the circadian timing system profoundly influences cognitive performance, the underlying molecular mechanisms remain poorly defined. Our previous work has found that the mitogen-activated protein kinase-interacting kinase (MNK)-eukaryotic translation initiation factor 4E (eIF4E) axis, a conserved cellular signalling pathway regulating mRNA translation, modulates the function of the suprachiasmatic nucleus (SCN), the master circadian clock. Here, with the use of a combination of genetic, biochemical and behavioural approaches, we investigated the distribution and temporal regulation of eIF4E phosphorylation in the brain and its role in regulating the diurnal oscillations of some aspects of cognition in mice. We found that activities of the MNK-eIF4E axis, as indicated by the level of eIF4E phosphorylation at Ser209, exhibited significant circadian oscillations in a variety of brain regions, including but not limited to the prefrontal cortex, the hippocampus, the amygdala and the cerebellum. Phosphorylated eIF4E was enriched in neurons but not in astrocytes or microglia. Mice lacking eIF4E phosphorylation (eIF4ES209A/S209A ) or the MNKs (Mnk1-/-,2-/- ), the kinases that phosphorylate eIF4E, exhibited impaired diurnal variations of novel object recognition, object location memory, Barnes maze learning and ambulatory activities. Together, these results suggest that circadian activities of the MNK-eIF4E axis contribute to the diurnal rhythms of some cognitive functions, highlighting a role for rhythmic translational control in circadian regulation of cognitive performance.
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Affiliation(s)
- Dong Liu
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Jin Li
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA.,Institute of Neuroscience and Translational Medicine, College of Life Science and Agronomy, Zhoukou Normal University, Zhoukou, China
| | - Hao Lin
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Ethan Lorsung
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Nam Le
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Rubal Singla
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Abhishek Mishra
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Rikiro Fukunaga
- Department of Biochemistry, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Japan
| | - Ruifeng Cao
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA.,Department of Neuroscience, University of Minnesota Medical School, Minneapolis, MN, USA
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Ruby NF. Suppression of Circadian Timing and Its Impact on the Hippocampus. Front Neurosci 2021; 15:642376. [PMID: 33897354 PMCID: PMC8060574 DOI: 10.3389/fnins.2021.642376] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 03/17/2021] [Indexed: 01/02/2023] Open
Abstract
In this article, I describe the development of the disruptive phase shift (DPS) protocol and its utility for studying how circadian dysfunction impacts memory processing in the hippocampus. The suprachiasmatic nucleus (SCN) of the Siberian hamster is a labile circadian pacemaker that is easily rendered arrhythmic (ARR) by a simple manipulation of ambient lighting. The DPS protocol uses room lighting to administer a phase-advancing signal followed by a phase-delaying signal within one circadian cycle to suppress clock gene rhythms in the SCN. The main advantage of this model for inducing arrhythmia is that the DPS protocol is non-invasive; circadian rhythms are eliminated while leaving the animals neurologically and genetically intact. In the area of learning and memory, DPS arrhythmia produces much different results than arrhythmia by surgical ablation of the SCN. As I show, SCN ablation has little to no effect on memory. By contrast, DPS hamsters have an intact, but arrhythmic, SCN which produces severe deficits in memory tasks that are accompanied by fragmentation of electroencephalographic theta oscillations, increased synaptic inhibition in hippocampal circuits, and diminished responsiveness to cholinergic signaling in the dentate gyrus of the hippocampus. The studies reviewed here show that DPS hamsters are a promising model for translational studies of adult onset circadian dysfunction in humans.
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Affiliation(s)
- Norman F. Ruby
- Biology Department, Stanford University, Stanford, CA, United States
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McMartin L, Kiraly M, Heller HC, Madison DV, Ruby NF. Disruption of circadian timing increases synaptic inhibition and reduces cholinergic responsiveness in the dentate gyrus. Hippocampus 2021; 31:422-434. [PMID: 33439521 PMCID: PMC8048473 DOI: 10.1002/hipo.23301] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 12/28/2020] [Accepted: 01/02/2021] [Indexed: 12/11/2022]
Abstract
We investigated synaptic mechanisms in the hippocampus that could explain how loss of circadian timing leads to impairments in spatial and recognition memory. Experiments were performed in hippocampal slices from Siberian hamsters (Phodopus sungorus) because, unlike mice and rats, their circadian rhythms are easily eliminated without modifications to their genome and without surgical manipulations, thereby leaving neuronal circuits intact. Recordings of excitatory postsynaptic field potentials and population spikes in area CA1 and dentate gyrus granule cells revealed no effect of circadian arrhythmia on basic functions of synaptic circuitry, including long-term potentiation. However, dentate granule cells from circadian-arrhythmic animals maintained a more depolarized resting membrane potential than cells from circadian-intact animals; a significantly greater proportion of these cells depolarized in response to the cholinergic agonist carbachol (10 μM), and did so by increasing their membrane potential three-fold greater than cells from the control (entrained) group. Dentate granule cells from arrhythmic animals also exhibited higher levels of tonic inhibition, as measured by the frequency of spontaneous inhibitory postsynaptic potentials. Carbachol also decreased stimulus-evoked synaptic excitation in dentate granule cells from both intact and arrhythmic animals as expected, but reduced stimulus-evoked synaptic inhibition only in cells from control hamsters. These findings show that loss of circadian timing is accompanied by greater tonic inhibition, and increased synaptic inhibition in response to muscarinic receptor activation in dentate granule cells. Increased inhibition would likely attenuate excitation in dentate-CA3 microcircuits, which in turn might explain the spatial memory deficits previously observed in circadian-arrhythmic hamsters.
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Affiliation(s)
- Laura McMartin
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, USA
| | - Marianna Kiraly
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, USA
| | - H Craig Heller
- Biology Department, Stanford University, Stanford, California, USA
| | - Daniel V Madison
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, USA
| | - Norman F Ruby
- Biology Department, Stanford University, Stanford, California, USA
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