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Ono D, Weaver DR, Hastings MH, Honma KI, Honma S, Silver R. The Suprachiasmatic Nucleus at 50: Looking Back, Then Looking Forward. J Biol Rhythms 2024; 39:135-165. [PMID: 38366616 PMCID: PMC7615910 DOI: 10.1177/07487304231225706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2024]
Abstract
It has been 50 years since the suprachiasmatic nucleus (SCN) was first identified as the central circadian clock and 25 years since the last overview of developments in the field was published in the Journal of Biological Rhythms. Here, we explore new mechanisms and concepts that have emerged in the subsequent 25 years. Since 1997, methodological developments, such as luminescent and fluorescent reporter techniques, have revealed intricate relationships between cellular and network-level mechanisms. In particular, specific neuropeptides such as arginine vasopressin, vasoactive intestinal peptide, and gastrin-releasing peptide have been identified as key players in the synchronization of cellular circadian rhythms within the SCN. The discovery of multiple oscillators governing behavioral and physiological rhythms has significantly advanced our understanding of the circadian clock. The interaction between neurons and glial cells has been found to play a crucial role in regulating these circadian rhythms within the SCN. Furthermore, the properties of the SCN network vary across ontogenetic stages. The application of cell type-specific genetic manipulations has revealed components of the functional input-output system of the SCN and their correlation with physiological functions. This review concludes with the high-risk effort of identifying open questions and challenges that lie ahead.
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Affiliation(s)
- Daisuke Ono
- Stress Recognition and Response, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - David R Weaver
- Department of Neurobiology and NeuroNexus Institute, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Michael H Hastings
- Division of Neurobiology, MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Ken-Ichi Honma
- Research and Education Center for Brain Science, Hokkaido University, Sapporo, Japan
- Center for Sleep and Circadian Rhythm Disorders, Sapporo Hanazono Hospital, Sapporo, Japan
| | - Sato Honma
- Research and Education Center for Brain Science, Hokkaido University, Sapporo, Japan
- Center for Sleep and Circadian Rhythm Disorders, Sapporo Hanazono Hospital, Sapporo, Japan
| | - Rae Silver
- Stress Recognition and Response, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
- Department of Neural Regulation, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Department of Neuroscience & Behavior, Barnard College and Department of Psychology, Columbia University, New York City, New York, USA
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2
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Walker CD, Delorme TC, Kiessling S, Long H, Cermakian N. Peripheral clock gene oscillations are perturbed in neonatal and adult rat offspring raised under adverse limited bedding conditions. Sci Rep 2023; 13:22886. [PMID: 38129480 PMCID: PMC10739797 DOI: 10.1038/s41598-023-47968-y] [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: 08/22/2023] [Accepted: 11/20/2023] [Indexed: 12/23/2023] Open
Abstract
Circadian (24-h) rhythms in the suprachiasmatic nucleus (SCN) are established in utero in rodents, but rhythmicity of peripheral circadian clocks appears later in postnatal development. Since peripheral oscillators can be influenced by maternal feeding and behavior, we investigated whether exposure to the adverse environmental conditions of limited bedding (LB) during postnatal life would alter rhythmicity in the SCN, adrenal gland and liver in neonatal (postnatal day PND10), juvenile (PND28) and adult rats. We also examined locomotor activity in adults. Limited bedding increased nursing time and slightly increased fragmentation of maternal behavior. Exposure to LB reduced the amplitude of Per2 in the SCN on PND10. Adrenal clock gene expression (Bmal1, Per2, Cry1, Rev-erbα, Dbp) and corticosterone secretion were rhythmic at all ages in NB offspring, whereas rhythmicity of Bmal1, Cry1 and corticosterone was abolished in neonatal LB pups. Circadian gene expression in the adrenal and liver was well established by PND28. In adults, liver expression of several circadian genes was increased at specific daytimes by LB and the microstructure of locomotor behavior was altered. Thus, changes in maternal care and behavior might provide important signals to the maturing peripheral oscillators and modify, in particular their output functions in the long-term.
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Affiliation(s)
- Claire-Dominique Walker
- Douglas Mental Health University Institute, 6875 Lasalle Blvd, Montreal, QC, H4H 1R3, Canada.
- Dept of Psychiatry, McGill University, Montreal, QC, Canada.
| | - Tara C Delorme
- Douglas Mental Health University Institute, 6875 Lasalle Blvd, Montreal, QC, H4H 1R3, Canada
| | - Silke Kiessling
- Faculty of Health and Medical Sciences, University of Surrey, Stag Hill Campus, Guildford, GU27XH, UK
| | - Hong Long
- Douglas Mental Health University Institute, 6875 Lasalle Blvd, Montreal, QC, H4H 1R3, Canada
| | - Nicolas Cermakian
- Douglas Mental Health University Institute, 6875 Lasalle Blvd, Montreal, QC, H4H 1R3, Canada
- Dept of Psychiatry, McGill University, Montreal, QC, Canada
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3
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Chen R, Routh BN, Gaudet AD, Fonken LK. Circadian Regulation of the Neuroimmune Environment Across the Lifespan: From Brain Development to Aging. J Biol Rhythms 2023; 38:419-446. [PMID: 37357738 PMCID: PMC10475217 DOI: 10.1177/07487304231178950] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
Circadian clocks confer 24-h periodicity to biological systems, to ultimately maximize energy efficiency and promote survival in a world with regular environmental light cycles. In mammals, circadian rhythms regulate myriad physiological functions, including the immune, endocrine, and central nervous systems. Within the central nervous system, specialized glial cells such as astrocytes and microglia survey and maintain the neuroimmune environment. The contributions of these neuroimmune cells to both homeostatic and pathogenic demands vary greatly across the day. Moreover, the function of these cells changes across the lifespan. In this review, we discuss circadian regulation of the neuroimmune environment across the lifespan, with a focus on microglia and astrocytes. Circadian rhythms emerge in early life concurrent with neuroimmune sculpting of brain circuits and wane late in life alongside increasing immunosenescence and neurodegeneration. Importantly, circadian dysregulation can alter immune function, which may contribute to susceptibility to neurodevelopmental and neurodegenerative diseases. In this review, we highlight circadian neuroimmune interactions across the lifespan and share evidence that circadian dysregulation within the neuroimmune system may be a critical component in human neurodevelopmental and neurodegenerative diseases.
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Affiliation(s)
- Ruizhuo Chen
- Division of Pharmacology & Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas
| | - Brandy N. Routh
- Division of Pharmacology & Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas
- Institute for Neuroscience, The University of Texas at Austin, Austin, Texas
| | - Andrew D. Gaudet
- Institute for Neuroscience, The University of Texas at Austin, Austin, Texas
- Department of Psychology, The University of Texas at Austin, Austin, Texas
- Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, Texas
| | - Laura K. Fonken
- Division of Pharmacology & Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas
- Institute for Neuroscience, The University of Texas at Austin, Austin, Texas
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4
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Carmona-Alcocer V, Brown LS, Anchan A, Rohr KE, Evans JA. Developmental patterning of peptide transcription in the central circadian clock in both sexes. Front Neurosci 2023; 17:1177458. [PMID: 37274219 PMCID: PMC10235759 DOI: 10.3389/fnins.2023.1177458] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 04/21/2023] [Indexed: 06/06/2023] Open
Abstract
Introduction Neuropeptide signaling modulates the function of central clock neurons in the suprachiasmatic nucleus (SCN) during development and adulthood. Arginine vasopressin (AVP) and vasoactive intestinal peptide (VIP) are expressed early in SCN development, but the precise timing of transcriptional onset has been difficult to establish due to age-related changes in the rhythmic expression of each peptide. Methods To provide insight into spatial patterning of peptide transcription during SCN development, we used a transgenic approach to define the onset of Avp and Vip transcription. Avp-Cre or Vip-Cre males were crossed to Ai9+/+ females, producing offspring in which the fluorescent protein tdTomato (tdT) is expressed at the onset of Avp or Vip transcription. Spatial patterning of Avp-tdT and Vip-tdT expression was examined at critical developmental time points spanning mid-embryonic age to adulthood in both sexes. Results We find that Avp-tdT and Vip-tdT expression is initiated at different developmental time points in spatial subclusters of SCN neurons, with developmental patterning that differs by sex. Conclusions These data suggest that SCN neurons can be distinguished into further subtypes based on the developmental patterning of neuropeptide expression, which may contribute to regional and/or sex differences in cellular function in adulthood.
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Affiliation(s)
- Vania Carmona-Alcocer
- Department of Biomedical Science, Marquette University, Milwaukee, WI, United States
| | - Lindsey S. Brown
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Allston, MA, United States
| | - Aiesha Anchan
- Department of Biomedical Science, Marquette University, Milwaukee, WI, United States
| | - Kayla E. Rohr
- Department of Biomedical Science, Marquette University, Milwaukee, WI, United States
| | - Jennifer A. Evans
- Department of Biomedical Science, Marquette University, Milwaukee, WI, United States
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Lehmann M, Haury K, Oster H, Astiz M. Circadian glucocorticoids throughout development. Front Neurosci 2023; 17:1165230. [PMID: 37179561 PMCID: PMC10166844 DOI: 10.3389/fnins.2023.1165230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 04/06/2023] [Indexed: 05/15/2023] Open
Abstract
Glucocorticoids (GCs) are essential drivers of mammalian tissue growth and maturation during one of the most critical developmental windows, the perinatal period. The developing circadian clock is shaped by maternal GCs. GC deficits, excess, or exposure at the wrong time of day leads to persisting effects later in life. During adulthood, GCs are one of the main hormonal outputs of the circadian system, peaking at the beginning of the active phase (i.e., the morning in humans and the evening in nocturnal rodents) and contributing to the coordination of complex functions such as energy metabolism and behavior, across the day. Our article discusses the current knowledge on the development of the circadian system with a focus on the role of GC rhythm. We explore the bidirectional interaction between GCs and clocks at the molecular and systemic levels, discuss the evidence of GC influence on the master clock in the suprachiasmatic nuclei (SCN) of the hypothalamus during development and in the adult system.
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Affiliation(s)
- Marianne Lehmann
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany
| | - Katharina Haury
- Achucarro Basque Center for Neuroscience, Science Park of the UPV/EHU, Leioa, Spain
| | - Henrik Oster
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany
| | - Mariana Astiz
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany
- Achucarro Basque Center for Neuroscience, Science Park of the UPV/EHU, Leioa, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
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6
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Lathe R, St Clair D. Programmed ageing: decline of stem cell renewal, immunosenescence, and Alzheimer's disease. Biol Rev Camb Philos Soc 2023. [PMID: 37068798 DOI: 10.1111/brv.12959] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 03/27/2023] [Accepted: 03/30/2023] [Indexed: 04/19/2023]
Abstract
The characteristic maximum lifespan varies enormously across animal species from a few hours to hundreds of years. This argues that maximum lifespan, and the ageing process that itself dictates lifespan, are to a large extent genetically determined. Although controversial, this is supported by firm evidence that semelparous species display evolutionarily programmed ageing in response to reproductive and environmental cues. Parabiosis experiments reveal that ageing is orchestrated systemically through the circulation, accompanied by programmed changes in hormone levels across a lifetime. This implies that, like the circadian and circannual clocks, there is a master 'clock of age' (circavital clock) located in the limbic brain of mammals that modulates systemic changes in growth factor and hormone secretion over the lifespan, as well as systemic alterations in gene expression as revealed by genomic methylation analysis. Studies on accelerated ageing in mice, as well as human longevity genes, converge on evolutionarily conserved fibroblast growth factors (FGFs) and their receptors, including KLOTHO, as well as insulin-like growth factors (IGFs) and steroid hormones, as key players mediating the systemic effects of ageing. Age-related changes in these and multiple other factors are inferred to cause a progressive decline in tissue maintenance through failure of stem cell replenishment. This most severely affects the immune system, which requires constant renewal from bone marrow stem cells. Age-related immune decline increases risk of infection whereas lifespan can be extended in germfree animals. This and other evidence suggests that infection is the major cause of death in higher organisms. Immune decline is also associated with age-related diseases. Taking the example of Alzheimer's disease (AD), we assess the evidence that AD is caused by immunosenescence and infection. The signature protein of AD brain, Aβ, is now known to be an antimicrobial peptide, and Aβ deposits in AD brain may be a response to infection rather than a cause of disease. Because some cognitively normal elderly individuals show extensive neuropathology, we argue that the location of the pathology is crucial - specifically, lesions to limbic brain are likely to accentuate immunosenescence, and could thus underlie a vicious cycle of accelerated immune decline and microbial proliferation that culminates in AD. This general model may extend to other age-related diseases, and we propose a general paradigm of organismal senescence in which declining stem cell proliferation leads to programmed immunosenescence and mortality.
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Affiliation(s)
- Richard Lathe
- Division of Infection Medicine, Chancellor's Building, University of Edinburgh Medical School, Little France, Edinburgh, EH16 4SB, UK
| | - David St Clair
- Institute of Medical Sciences, School of Medicine, University of Aberdeen, Aberdeen, AB25 2ZD, UK
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7
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Dasari SS, Archer M, Mohamed NE, Tewari AK, Figueiro MG, Kyprianou N. Circadian Rhythm Disruption as a Contributor to Racial Disparities in Prostate Cancer. Cancers (Basel) 2022; 14:cancers14205116. [PMID: 36291899 PMCID: PMC9600368 DOI: 10.3390/cancers14205116] [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: 08/18/2022] [Revised: 10/08/2022] [Accepted: 10/15/2022] [Indexed: 01/27/2023] Open
Abstract
In the United States, African American (AA) men have a 2.4 times higher mortality rate due to prostate cancer than White men. The multifactorial causes of the racial disparities in prostate cancer involve various social determinants of health, socioeconomic status, and access to healthcare. However, emerging evidence also suggests that circadian rhythm disruption (CRD) contributes to prostate cancer, and AA men may be more susceptible to developing CRDs. Circadian rhythms play a significant role in metabolism, hormone secretion, and sleep/wake cycles. Disruption in these circadian rhythms can be caused by airplane travel/jetlag, night shift work, exposure to light, and neighborhood noise levels, which can contribute to sleep disorders and chronic conditions such as obesity, diabetes, cardiovascular disease, and depression. The drivers of the racial disparities in CRD include night shift work, racial discrimination, elevated stress, and residing in poor neighborhoods characterized by high noise pollution. Given the increased vulnerability of AA men to CRDs, and the role that CRDs play in prostate cancer, elucidating the clock-related prostate cancer pathways and their behavior and environmental covariates may be critical to better understanding and reducing the racial disparities in prostate cancer.
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Affiliation(s)
- Sonali S. Dasari
- Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Maddison Archer
- Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Nihal E. Mohamed
- Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Tisch Cancer Institute, Mount Sinai Health, New York, NY 10029, USA
| | - Ashutosh K. Tewari
- Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Tisch Cancer Institute, Mount Sinai Health, New York, NY 10029, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Mariana G. Figueiro
- Tisch Cancer Institute, Mount Sinai Health, New York, NY 10029, USA
- Light and Health Research Center, Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Correspondence: (M.G.F.); (N.K.)
| | - Natasha Kyprianou
- Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Tisch Cancer Institute, Mount Sinai Health, New York, NY 10029, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Correspondence: (M.G.F.); (N.K.)
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8
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Benevento M, Hökfelt T, Harkany T. Ontogenetic rules for the molecular diversification of hypothalamic neurons. Nat Rev Neurosci 2022; 23:611-627. [PMID: 35906427 DOI: 10.1038/s41583-022-00615-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/14/2022] [Indexed: 11/09/2022]
Abstract
The hypothalamus is an evolutionarily conserved endocrine interface that, among other roles, links central homeostatic control to adaptive bodily responses by releasing hormones and neuropeptides from its many neuronal subtypes. In its preoptic, anterior, tuberal and mammillary subdivisions, a kaleidoscope of magnocellular and parvocellular neuroendocrine command neurons, local-circuit neurons, and neurons that project to extrahypothalamic areas are intermingled in partially overlapping patches of nuclei. Molecular fingerprinting has produced data of unprecedented mass and depth to distinguish and even to predict the synaptic and endocrine competences, connectivity and stimulus selectivity of many neuronal modalities. These new insights support eminent studies from the past century but challenge others on the molecular rules that shape the developmental segregation of hypothalamic neuronal subtypes and their use of morphogenic cues for terminal differentiation. Here, we integrate single-cell RNA sequencing studies with those of mouse genetics and endocrinology to describe key stages of hypothalamus development, including local neurogenesis, the direct terminal differentiation of glutamatergic neurons, transition cascades for GABAergic and GABAergic cell-derived dopamine cells, waves of local neuronal migration, and sequential enrichment in neuropeptides and hormones. We particularly emphasize how transcription factors determine neuronal identity and, consequently, circuit architecture, and whether their deviations triggered by environmental factors and hormones provoke neuroendocrine illnesses.
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Affiliation(s)
- Marco Benevento
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Tomas Hökfelt
- Department of Neuroscience, Biomedicum 7D, Karolinska Institutet, Solna, Sweden
| | - Tibor Harkany
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria. .,Department of Neuroscience, Biomedicum 7D, Karolinska Institutet, Solna, Sweden.
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9
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Tonsfeldt KJ, Mellon PL, Hoffmann HM. Circadian Rhythms in the Neuronal Network Timing the Luteinizing Hormone Surge. Endocrinology 2022; 163:6490154. [PMID: 34967900 PMCID: PMC8782605 DOI: 10.1210/endocr/bqab268] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Indexed: 01/01/2023]
Abstract
For billions of years before electric light was invented, life on Earth evolved under the pattern of light during the day and darkness during the night. Through evolution, nearly all organisms internalized the temporal rhythm of Earth's 24-hour rotation and evolved self-sustaining biological clocks with a ~24-hour rhythm. These internal rhythms are called circadian rhythms, and the molecular constituents that generate them are called molecular circadian clocks. Alignment of molecular clocks with the environmental light-dark rhythms optimizes physiology and behavior. This phenomenon is particularly true for reproductive function, in which seasonal breeders use day length information to time yearly changes in fertility. However, it is becoming increasingly clear that light-induced disruption of circadian rhythms can negatively impact fertility in nonseasonal breeders as well. In particular, the luteinizing hormone surge promoting ovulation is sensitive to circadian disruption. In this review, we will summarize our current understanding of the neuronal networks that underlie circadian rhythms and the luteinizing hormone surge.
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Affiliation(s)
- Karen J Tonsfeldt
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Pamela L Mellon
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, CA, 92093, USA
- Correspondence: Pamela L. Mellon, Ph.D., University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, USA 92093-0674.
| | - Hanne M Hoffmann
- Department of Animal Science and the Reproductive and Developmental Sciences Program, Michigan State University, 766 Service Road, East Lansing, MI, 48824, USA
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10
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Andreatta G, Allen CN. How neurons adjust to diurnality. eLife 2021; 10:e74704. [PMID: 34845985 PMCID: PMC8631939 DOI: 10.7554/elife.74704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Being active during the day requires a slow-closing ion channel that dampens the activity of neurons in a specific area of the brain.
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Affiliation(s)
- Gabriele Andreatta
- Department of Microbiology, Immunobiology and Genetics, Max Perutz Labs, University of ViennaViennaAustria
| | - Charles N Allen
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Department of Behavioral NeurosciencePortlandUnited States
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11
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de Andrade Silva SC, da Silva AI, Braz GRF, da Silva Pedroza AA, de Lemos MDT, Sellitti DF, Lagranha C. Overfeeding during development induces temporally-dependent changes in areas controlling food intake in the brains of male Wistar rats. Life Sci 2021; 285:119951. [PMID: 34516994 DOI: 10.1016/j.lfs.2021.119951] [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: 06/11/2021] [Revised: 09/05/2021] [Accepted: 09/06/2021] [Indexed: 10/20/2022]
Abstract
AIMS We sought to evaluate the effects of overfeeding during lactation on the feeding behavior and expression of specific regulatory genes in brain areas associated with food intake in 22- and 60-day old male rats. METHODS We evaluated body weight, food intake of standard and palatable diet, and mRNA expression of dopamine receptor D1 (DDR1), dopamine receptor (DDR2), melanocortin 4 receptor (MC4R), the μ-opioid receptor (MOR), neuropeptide Y (NPY), agouti-related protein (AGRP), proopiomelanocortin (POMC), cocaine-and amphetamine-regulated transcript (CART), serotonin (5-hydroxytryptamine; 5-HT) transporter (SERT), 5-hydroxytryptamine receptor 1B (5-HT1B), 5-hydroxytryptamine receptor 2C receptor (5-HT2C), Clock (CLOK), cryptochrome protein 1 (Cry1) and period circadian protein homolog 2 (Per2) in the striatum, hypothalamus and brainstem of male rats at post-natal days (PND) 22 and 60. KEY FINDINGS Overfeeding resulted in significantly increased body weight through PND60, and a 2-fold increase in palatable food intake at PND22, but not at PND60. We observed significant increases in DDR1, DDR2, and MC4R gene expression in the striatum and brainstem and POMC/CART in the hypothalamus of the OF group at PND22 that were reversed by PND60. Hypothalamic levels of 5-HT1B, 5-HT2C and NPY/AGRP on the other hand were decreased at PND22 and increased at PND60 in OF animals. Clock genes were unaffected by OF at PND22, but were significantly elevated at PND60. SIGNIFICANCE Overfeeding during early development of the rat brain results in obesity and altered feeding behavior in early adulthood. The altered behavior might be the consequence of the changes in food intake and reward gene expression.
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Affiliation(s)
| | - Aline Isabel da Silva
- Neuropsychiatry and Behavior Science Graduate Program, Universidade Federal de Pernambuco -UFPE-Recife, PE, Brazil
| | - Glauber Rudá Feitoza Braz
- Neuropsychiatry and Behavior Science Graduate Program, Universidade Federal de Pernambuco -UFPE-Recife, PE, Brazil
| | | | | | - Donald F Sellitti
- Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Claudia Lagranha
- Neuropsychiatry and Behavior Science Graduate Program, Universidade Federal de Pernambuco -UFPE-Recife, PE, Brazil; Laboratory of Biochemistry and Exercise Biochemistry, Universidade Federal de Pernambuco - UFPE, Recife, PE, Brazil.
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12
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Poe AR, Mace KD, Kayser MS. Getting into rhythm: developmental emergence of circadian clocks and behaviors. FEBS J 2021; 289:6576-6588. [PMID: 34375504 DOI: 10.1111/febs.16157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 06/30/2021] [Accepted: 08/09/2021] [Indexed: 11/28/2022]
Abstract
Circadian clocks keep time to coordinate diverse behaviors and physiological functions. While molecular circadian rhythms are evident during early development, most behavioral rhythms, such as sleep-wake, do not emerge until far later. Here, we examine the development of circadian clocks, outputs, and behaviors across phylogeny, with a particular focus on Drosophila. We explore potential mechanisms for how central clocks and circadian output loci establish communication, and discuss why from an evolutionary perspective sleep-wake and other behavioral rhythms emerge long after central clocks begin keeping time.
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Affiliation(s)
- Amy R Poe
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.,Chronobiology and Sleep Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Kyla D Mace
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.,Pharmacology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Matthew S Kayser
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.,Chronobiology and Sleep Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.,Department of Neuroscience, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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13
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Sleep-wake cycle disturbances and NeuN-altered expression in adult rats after cannabidiol treatments during adolescence. Psychopharmacology (Berl) 2021; 238:1437-1447. [PMID: 33635384 DOI: 10.1007/s00213-021-05769-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 01/20/2021] [Indexed: 12/14/2022]
Abstract
RATIONALE The medical uses of cannabidiol (CBD), a constituent of the Cannabis sativa, have accelerated the legal and social acceptance for CBD-based medications but has also given the momentum for questioning whether the long-term use of CBD during the early years of life may induce adverse neurobiological effects in adulthood, including sleep disturbances. Given the critical window for neuroplasticity and neuro-functional changes that occur during stages of adolescence, we hypothesized that CBD might influence the sleep-wake cycle in adult rats after their exposure to CBD during the adolescence. OBJECTIVES Here, we investigated the effects upon behavior and neural activity in adulthood after long-term administrations of CBD in juvenile rats. METHODS We pre-treated juvenile rats with CBD (5 or 30 mg/Kg, daily) from post-natal day (PND) 30 and during 2 weeks. Following the treatments, the sleep-wake cycle and NeuN expression was analyzed at PND 80. RESULTS We found that systemic injections of CBD (5 or 30 mg/Kg, i.p.) given to adolescent rats (post-natal day 30) for 14 days increased in adulthood the wakefulness and decreased rapid eye movement sleep during the lights-on period whereas across the lights-off period, wakefulness was diminished and slow wave sleep was enhanced. In addition, we found that adult animals that received CBD during the adolescence displayed disruptions in sleep rebound period after total sleep deprivation. Finally, we determined how the chronic administrations of CBD during the adolescence affected in the adulthood the NeuN expression in the suprachiasmatic nucleus, a sleep-related brain region. CONCLUSIONS Our findings are relevant for interpreting results of adult rats that were chronically exposed to CBD during the adolescence and provide new insights into how CBD may impact the sleep-wake cycle and neuronal activity during developmental stages.
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Lužná V, Houdek P, Liška K, Sumová A. Challenging the Integrity of Rhythmic Maternal Signals Revealed Gene-Specific Responses in the Fetal Suprachiasmatic Nuclei. Front Neurosci 2021; 14:613531. [PMID: 33488354 PMCID: PMC7817817 DOI: 10.3389/fnins.2020.613531] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 12/02/2020] [Indexed: 12/27/2022] Open
Abstract
During fetal stage, maternal circadian system sets the phase of the developing clock in the suprachiasmatic nuclei (SCN) via complex pathways. We addressed the issue of how impaired maternal signaling due to a disturbed environmental light/dark (LD) cycle affects the fetal SCN. We exposed pregnant Wistar rats to two different challenges - a 6-h phase shift in the LD cycle on gestational day 14, or exposure to constant light (LL) throughout pregnancy - and detected the impact on gene expression profiles in 19-day-old fetuses. The LD phase shift, which changed the maternal SCN into a transient state, caused robust downregulation of expression profiles of clock genes (Per1, Per2, and Nr1d1), clock-controlled (Dbp) genes, as well as genes involved in sensing various signals, such as c-fos and Nr3c1. Removal of the rhythmic maternal signals via exposure of pregnant rats to LL abolished the rhythms in expression of c-fos and Nr3c1 in the fetal SCN. We identified c-fos as the gene primarily responsible for sensing rhythmic maternal signals because its expression profile tracked the shifted or arrhythmic maternal SCN clock. Pathways related to the maternal rhythmic behavioral state were likely not involved in driving the c-fos expression rhythm. Instead, introduction of a behavioral rhythm to LL-exposed mothers via restricted feeding regime strengthened rhythm in Vip expression in the fetal SCN. Our results revealed for the first time that the fetal SCN is highly sensitive in a gene-specific manner to various changes in maternal signaling due to disturbances of environmental cycles related to the modern lifestyle in humans.
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Affiliation(s)
- Vendula Lužná
- Laboratory of Biological Rhythms, Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Pavel Houdek
- Laboratory of Biological Rhythms, Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Karolína Liška
- Laboratory of Biological Rhythms, Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Alena Sumová
- Laboratory of Biological Rhythms, Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
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15
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Bedont JL, Iascone DM, Sehgal A. The Lineage Before Time: Circadian and Nonclassical Clock Influences on Development. Annu Rev Cell Dev Biol 2020; 36:469-509. [PMID: 33021821 PMCID: PMC10826104 DOI: 10.1146/annurev-cellbio-100818-125454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Diverse factors including metabolism, chromatin remodeling, and mitotic kinetics influence development at the cellular level. These factors are well known to interact with the circadian transcriptional-translational feedback loop (TTFL) after its emergence. What is only recently becoming clear, however, is how metabolism, mitosis, and epigenetics may become organized in a coordinated cyclical precursor signaling module in pluripotent cells prior to the onset of TTFL cycling. We propose that both the precursor module and the TTFL module constrain cellular identity when they are active during development, and that the emergence of these modules themselves is a key lineage marker. Here we review the component pathways underlying these ideas; how proliferation, specification, and differentiation decisions in both developmental and adult stem cell populations are or are not regulated by the classical TTFL; and emerging evidence that we propose implies a primordial clock that precedes the classical TTFL and influences early developmental decisions.
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Affiliation(s)
- Joseph Lewis Bedont
- Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Daniel Maxim Iascone
- Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Amita Sehgal
- Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
- The Howard Hughes Medical Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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16
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The circadian phase of antenatal glucocorticoid treatment affects the risk of behavioral disorders. Nat Commun 2020; 11:3593. [PMID: 32681096 PMCID: PMC7367845 DOI: 10.1038/s41467-020-17429-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 06/29/2020] [Indexed: 12/26/2022] Open
Abstract
During pregnancy, maternal endocrine signals drive fetal development and program the offspring's physiology. A disruption of maternal glucocorticoid (GC) homeostasis increases the child's risk of developing psychiatric disorders later in life. We here show in mice, that the time of day of antenatal GC exposure predicts the behavioral phenotype of the adult offspring. Offspring of mothers receiving GCs out-of-phase compared to their endogenous circadian GC rhythm show elevated anxiety, impaired stress coping, and dysfunctional stress-axis regulation. The fetal circadian clock determines the vulnerability of the stress axis to GC treatment by controlling GC receptor (GR) availability in the hypothalamus. Similarly, a retrospective observational study indicates poorer stress compensatory capacity in 5-year old preterm infants whose mothers received antenatal GCs towards the evening. Our findings offer insights into the circadian physiology of feto-maternal crosstalk and assign a role to the fetal clock as a temporal gatekeeper of GC sensitivity.
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Mazuski C, Chen SP, Herzog ED. Different Roles for VIP Neurons in the Neonatal and Adult Suprachiasmatic Nucleus. J Biol Rhythms 2020; 35:465-475. [PMID: 32536240 DOI: 10.1177/0748730420932073] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The suprachiasmatic nucleus (SCN) drives circadian rhythms in locomotion through coupled, single-cell oscillations. Global genetic deletion of the neuropeptide Vip or its receptor Vipr2 results in profound deficits in daily synchrony among SCN cells and daily rhythms in locomotor behavior and glucocorticoid secretion. To test whether this phenotype depends on vasoactive intestinal polypeptide (VIP) neurons in the SCN, we ablated VIP SCN neurons in vivo in adult male mice through Caspase3-mediated induction of the apoptotic pathway in cre-expressing VIP neurons. We found that ablation of VIP SCN neurons in adult mice caused a phenotype distinct from Vip- and Vipr2-null mice. Mice lacking VIP neurons retained rhythmic locomotor activity with a shortened circadian period, more variable onsets, and decreased duration of daily activity. Circadian hormonal outputs, specifically corticosterone rhythms, were severely dampened. In contrast, deletion of neonatal SCN VIP neurons dramatically reduced circadian gene expression in the cultured SCN, mimicking the effects of global deletion of Vip or Vipr2. These results suggest that SCN VIP neurons play a role in lengthening circadian period and stimulating the daily surge in glucocorticoids in adults and in synchronizing and sustaining daily rhythms among cells in the developing SCN.
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Affiliation(s)
- Cristina Mazuski
- Department of Biology, Washington University, St. Louis, Missouri
| | - Samantha P Chen
- Department of Biology, Washington University, St. Louis, Missouri
| | - Erik D Herzog
- Department of Biology, Washington University, St. Louis, Missouri
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18
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Joye DAM, Rohr KE, Keller D, Inda T, Telega A, Pancholi H, Carmona-Alcocer V, Evans JA. Reduced VIP Expression Affects Circadian Clock Function in VIP-IRES-CRE Mice (JAX 010908). J Biol Rhythms 2020; 35:340-352. [PMID: 32460660 DOI: 10.1177/0748730420925573] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Circadian rhythms are programmed by the suprachiasmatic nucleus (SCN), which relies on neuropeptide signaling to maintain daily timekeeping. Vasoactive intestinal polypeptide (VIP) is critical for SCN function, but the precise role of VIP neurons in SCN circuits is not fully established. To interrogate their contribution to SCN circuits, VIP neurons can be manipulated specifically using the DNA-editing enzyme Cre recombinase. Although the Cre transgene is assumed to be inert by itself, we find that VIP expression is reduced in both heterozygous and homozygous adult VIP-IRES-Cre mice (JAX 010908). Compared with wild-type mice, homozygous VIP-Cre mice display faster reentrainment and shorter free-running period but do not become arrhythmic in constant darkness. Consistent with this phenotype, homozygous VIP-Cre mice display intact SCN PER2::LUC rhythms, albeit with altered period and network organization. We present evidence that the ability to sustain molecular rhythms in the VIP-Cre SCN is not due to residual VIP signaling; rather, arginine vasopressin signaling helps to sustain SCN function at both intracellular and intercellular levels in this model. This work establishes that the VIP-IRES-Cre transgene interferes with VIP expression but that loss of VIP can be mitigated by other neuropeptide signals to help sustain SCN function. Our findings have implications for studies employing this transgenic model and provide novel insight into neuropeptide signals that sustain daily timekeeping in the master clock.
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Affiliation(s)
- Deborah A M Joye
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | - Kayla E Rohr
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | - Danielle Keller
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | - Thomas Inda
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | - Adam Telega
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | - Harshida Pancholi
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
| | | | - Jennifer A Evans
- Department of Biomedical Sciences, Marquette University, Milwaukee, Wisconsin
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19
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McNeill JK, Walton JC, Ryu V, Albers HE. The Excitatory Effects of GABA within the Suprachiasmatic Nucleus: Regulation of Na-K-2Cl Cotransporters (NKCCs) by Environmental Lighting Conditions. J Biol Rhythms 2020; 35:275-286. [PMID: 32406304 DOI: 10.1177/0748730420924271] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The suprachiasmatic nucleus (SCN) contains a pacemaker that generates circadian rhythms and entrains them with the 24-h light-dark cycle (LD). The SCN is composed of 16,000 to 20,000 heterogeneous neurons in bilaterally paired nuclei. γ-amino butyric acid (GABA) is the primary neurochemical signal within the SCN and plays a key role in regulating circadian function. While GABA is the primary inhibitory neurotransmitter in the brain, there is now evidence that GABA can also exert excitatory effects in the adult brain. Cation chloride cotransporters determine the effects of GABA on chloride equilibrium, thereby determining whether GABA produces hyperpolarizing or depolarizing actions following activation of GABAA receptors. The activity of Na-K-2Cl cotransporter1 (NKCC1), the most prevalent chloride influx cotransporter isoform in the brain, plays a critical role in determining whether GABA has depolarizing effects. In the present study, we tested the hypothesis that NKCC1 protein expression in the SCN is regulated by environmental lighting and displays daily and circadian changes in the intact circadian system of the Syrian hamster. In hamsters housed in constant light (LL), the overall NKCC1 immunoreactivity (NKCC1-ir) in the SCN was significantly greater than in hamsters housed in LD or constant darkness (DD), although NKCC1 protein levels in the SCN were not different between hamsters housed in LD and DD. In hamsters housed in LD cycles, no differences in NKCC1-ir within the SCN were observed over the 24-h cycle. NKCC1 protein in the SCN was found to vary significantly over the circadian cycle in hamsters housed in free-running conditions. Overall, NKCC1 protein was greater in the ventral SCN than in the dorsal SCN, although no significant differences were observed across lighting conditions or time of day in either subregion. These data support the hypothesis that NKCC1 protein expression can be regulated by environmental lighting and circadian mechanisms within the SCN.
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Affiliation(s)
- John K McNeill
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia
| | - James C Walton
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia
| | - Vitaly Ryu
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia
| | - H Elliott Albers
- Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia
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De Nobrega AK, Luz KV, Lyons LC. Resetting the Aging Clock: Implications for Managing Age-Related Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1260:193-265. [PMID: 32304036 DOI: 10.1007/978-3-030-42667-5_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Worldwide, individuals are living longer due to medical and scientific advances, increased availability of medical care and changes in public health policies. Consequently, increasing attention has been focused on managing chronic conditions and age-related diseases to ensure healthy aging. The endogenous circadian system regulates molecular, physiological and behavioral rhythms orchestrating functional coordination and processes across tissues and organs. Circadian disruption or desynchronization of circadian oscillators increases disease risk and appears to accelerate aging. Reciprocally, aging weakens circadian function aggravating age-related diseases and pathologies. In this review, we summarize the molecular composition and structural organization of the circadian system in mammals and humans, and evaluate the technological and societal factors contributing to the increasing incidence of circadian disorders. Furthermore, we discuss the adverse effects of circadian dysfunction on aging and longevity and the bidirectional interactions through which aging affects circadian function using examples from mammalian research models and humans. Additionally, we review promising methods for managing healthy aging through behavioral and pharmacological reinforcement of the circadian system. Understanding age-related changes in the circadian clock and minimizing circadian dysfunction may be crucial components to promote healthy aging.
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Affiliation(s)
- Aliza K De Nobrega
- Department of Biological Science, Program in Neuroscience, Florida State University, Tallahassee, FL, USA
| | - Kristine V Luz
- Department of Biological Science, Program in Neuroscience, Florida State University, Tallahassee, FL, USA
| | - Lisa C Lyons
- Department of Biological Science, Program in Neuroscience, Florida State University, Tallahassee, FL, USA.
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21
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Cai C, Cai P, Chu G. Selection of suitable reference genes for core clock gene expression analysis by real-time qPCR in rat ovary granulosa cells. Mol Biol Rep 2019; 46:2941-2946. [PMID: 31016616 DOI: 10.1007/s11033-019-04755-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 03/08/2019] [Indexed: 01/19/2023]
Abstract
Selection of a suitable endogenous reference gene is essential for investigating expression of clock genes Bmal1, Clock, Pers, Crys, Rev-erbα/β, and RORα/β/γ involved in the circadian system. In this study, we treated rat ovary granulosa cells with dexamethasone to synchronize circadian oscillation in vitro and determined expression levels of Bmal1 and Per2 and six candidate reference genes (Actb, Beta actin; B2m, Beta-2-microglobulin; Ppia, Cyclophilin A; Gapdh, Glyceraldehyde-3-phosphate dehydrogenase; Hprt, Hypoxanthine guanine phosphoribosyl transferase and Tbp, TATA-box-binding protein) using quantitative real-time PCR. We then employed three software programs, GeNorm, NormFinder, and BestKeeper, to analyze the expression data for the selection of the best reference gene. According to GeNorm, Tbp and B2m were assessed as the most stable reference genes; Tbp and Hprt were best by NormFinder and BestKeeper, respectively. Thus, we recommend Tbp as the most suitable reference gene for studying clock genes expression in rat ovary granulosa cells in vitro.
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Affiliation(s)
- Chuanjiang Cai
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, Shaanxi, 712100, People's Republic of China.
| | - Pengpeng Cai
- Sir Run Run Hospital, Nanjing Medical University, Nanjing, 211100, People's Republic of China
| | - Guiyan Chu
- College of Animal Science and Technology, Northwest Agriculture and Forestry University, Yangling, Shaanxi, 712100, People's Republic of China
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