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Begemann K, Neumann A, Oster H. Regulation and function of extra-SCN circadian oscillators in the brain. Acta Physiol (Oxf) 2020; 229:e13446. [PMID: 31965726 DOI: 10.1111/apha.13446] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 12/12/2022]
Abstract
Most organisms evolved endogenous, so called circadian clocks as internal timekeeping mechanisms allowing them to adapt to recurring changes in environmental demands brought about by 24-hour rhythms such as the light-dark cycle, temperature variations or changes in humidity. The mammalian circadian clock system is based on cellular oscillators found in all tissues of the body that are organized in a hierarchical fashion. A master pacemaker located in the suprachiasmatic nucleus (SCN) synchronizes peripheral tissue clocks and extra-SCN oscillators in the brain with each other and with external time. Different time cues (so called Zeitgebers) such as light, food intake, activity and hormonal signals reset the clock system through the SCN or by direct action at the tissue clock level. While most studies on non-SCN clocks so far have focused on peripheral tissues, several extra-SCN central oscillators were characterized in terms of circadian rhythm regulation and output. Some of them are directly innervated by the SCN pacemaker, while others receive indirect input from the SCN via other neural circuits or extra-brain structures. The specific physiological function of these non-SCN brain oscillators as well as their role in the regulation of the circadian clock network remains understudied. In this review we summarize our current knowledge about the regulation and function of extra-SCN circadian oscillators in different brain regions and devise experimental approaches enabling us to unravel the organization of the circadian clock network in the central nervous system.
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Affiliation(s)
| | | | - Henrik Oster
- Institute of Neurobiology University of Lübeck Lübeck Germany
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Halvorson CL, De Bond JP, Maloney SK, Smith JT. Thermoneutral conditions correct the obese phenotype in female, but not male, Kiss1r knockout mice. J Therm Biol 2020; 90:102592. [PMID: 32479387 DOI: 10.1016/j.jtherbio.2020.102592] [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] [Received: 01/24/2020] [Revised: 03/10/2020] [Accepted: 04/06/2020] [Indexed: 12/29/2022]
Abstract
Kisspeptin, a neuropeptide that activates gonadotropin-releasing hormone (GnRH) neurons, has also been implicated as a regulator of energy balance. Kisspeptin receptor (Kiss1r) knockout (KO) mice display an obese phenotype in adulthood compared to wild-type (WT) controls due to reduced energy expenditure. Additionally, experimental evidence shows that the temperature of typical rodent housing conditions (22 °C) increases the metabolism of mice above basal levels. Female Kiss1r KO mice show reduced core temperature and impaired temperature adaptation to an acute cold challenge, suggesting their temperature homeostasis processes are altered. The present study examined the phenotype of gonadectomised Kiss1r KO mice at both sub-thermoneutral and thermoneutral temperature (22 °C and 30 °C). Our results confirmed the obese phenotype in Kiss1r KO mice at 22 °C, and revealed a sexually dimorphic effect of thermal neutrality on the phenotype. In female KO mice, the obesity observed at 22 °C was attenuated at 30 °C. Plasma leptin levels were higher in KO than WT female mice at 22 °C (P < 0.001) but not at 30 °C. Importantly, the expression of Ucp1 mRNA in brown adipose tissue was lower in KO mice compared to WT mice at 22 °C (P < 0.05), but not different from WT at 30 °C. In male KO mice, a metabolic phenotype was observed at 22 °C and 30 °C. These results provide further evidence for kisspeptin-mediated regulation of adiposity via altered energy expenditure. Moreover, thermoneutral housing alleviated the obese phenotype in female Kiss1r KO mice, compared to WT, indicating the impairment in these mice may relate to an inability to adapt to the chronic cold stress that is experienced at 22 °C.
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Affiliation(s)
- C L Halvorson
- School of Human Sciences, The University of Western Australia, Perth, 6009, Australia
| | - J P De Bond
- School of Human Sciences, The University of Western Australia, Perth, 6009, Australia
| | - S K Maloney
- School of Human Sciences, The University of Western Australia, Perth, 6009, Australia
| | - J T Smith
- School of Human Sciences, The University of Western Australia, Perth, 6009, Australia.
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Harihar S, Ray S, Narayanan S, Santhoshkumar A, Ly T, Welch DR. Role of the tumor microenvironment in regulating the anti-metastatic effect of KISS1. Clin Exp Metastasis 2020; 37:209-223. [PMID: 32088827 PMCID: PMC7339126 DOI: 10.1007/s10585-020-10030-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 02/19/2020] [Indexed: 12/29/2022]
Abstract
KISS1, a metastasis suppressor gene, has been shown to block metastasis without affecting primary tumor formation. Loss of KISS1 leads to invasion and metastasis in multiple cancers, which is the leading cause of cancer morbidity and mortality. The discovery of KISS1 has provided a ray of hope for early clinical diagnosis and for designing effective treatments targeting metastatic cancer. However, this goal requires greater holistic understanding of its mechanism of action. In this review, we go back into history and highlight some key developments, from the discovery of KISS1 to its role in regulating multiple physiological processes including cancer. We discuss key emerging roles for KISS1, specifically interactions with tissue microenvironment to promote dormancy and regulation of tumor cell metabolism, acknowledged as some of the key players in tumor progression and metastasis. We finally discuss strategies whereby KISS1 might be exploited clinically to treat metastasis.
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Affiliation(s)
- Sitaram Harihar
- Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India.
| | - Srijit Ray
- Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India
| | - Samyukta Narayanan
- Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India
| | - Anirudh Santhoshkumar
- Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India
| | - Thuc Ly
- Department of Cancer Biology, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
- The University Kansas Cancer Center, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
| | - Danny R Welch
- Department of Cancer Biology, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
- The University Kansas Cancer Center, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
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54
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Baker FC, Siboza F, Fuller A. Temperature regulation in women: Effects of the menstrual cycle. Temperature (Austin) 2020; 7:226-262. [PMID: 33123618 PMCID: PMC7575238 DOI: 10.1080/23328940.2020.1735927] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 02/17/2020] [Accepted: 02/24/2020] [Indexed: 02/08/2023] Open
Abstract
Core body temperature changes across the ovulatory menstrual cycle, such that it is 0.3°C to 0.7°C higher in the post-ovulatory luteal phase when progesterone is high compared with the pre-ovulatory follicular phase. This temperature difference, which is most evident during sleep or immediately upon waking before any activity, is used by women as a retrospective indicator of an ovulatory cycle. Here, we review both historical and current literature aimed at characterizing changes in core body temperature across the menstrual cycle, considering the assessment of the circadian rhythm of core body temperature and thermoregulatory responses to challenges, including heat and cold exposure, exercise, and fever. We discuss potential mechanisms for the thermogenic effect of progesterone and the temperature-lowering effect of estrogen, and discuss effects on body temperature of exogenous formulations of these hormones as contained in oral contraceptives. We review new wearable temperature sensors aimed at tracking daily temperature changes of women across multiple menstrual cycles and highlight the need for future research on the validity and reliability of these devices. Despite the change in core body temperature across the menstrual cycle being so well identified, there remain gaps in our current understanding, particularly about the underlying mechanisms and microcircuitry involved in the temperature changes.
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Affiliation(s)
- Fiona C. Baker
- Center for Health Sciences, SRI International, Menlo Park, USA
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Felicia Siboza
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Andrea Fuller
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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55
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Yaw AM, Duong TV, Nguyen D, Hoffmann HM. Circadian rhythms in the mouse reproductive axis during the estrous cycle and pregnancy. J Neurosci Res 2020; 99:294-308. [PMID: 32128870 DOI: 10.1002/jnr.24606] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 01/17/2020] [Accepted: 02/12/2020] [Indexed: 12/26/2022]
Abstract
Molecular and behavioral timekeeping is regulated by the circadian system which includes the brain's suprachiasmatic nucleus (SCN) that translates environmental light information into neuronal and endocrine signals aligning peripheral tissue rhythms to the time of day. Despite the critical role of circadian rhythms in fertility, it remains unexplored how circadian rhythms change within reproductive tissues during pregnancy. To determine how estrous cycle and pregnancy impact phase relationships of reproductive tissues, we used PER2::Luciferase (PER2::LUC) circadian reporter mice and determined the time of day of PER2::LUC peak (phase) in the SCN, pituitary, uterus, and ovary. The relationships between reproductive tissue PER2::LUC phases changed throughout the estrous cycle and late pregnancy and were accompanied by changes to PER2::LUC period in the SCN, uterus, and ovary. To determine if the phase relationship adaptations were driven by sex steroids, we asked if progesterone, a hormone involved in estrous cyclicity and pregnancy, could regulate Per2-luciferase expression. Using an in vitro transfection assay, we found that progesterone increased Per2-luciferase expression in immortalized SCN (SCN2.2) and arcuate nucleus (KTAR) cells. In addition, progesterone shortened PER2::LUC period in ex vivo uterine tissue recordings collected during pregnancy. As progesterone dramatically increases during pregnancy, we evaluated wheel-running patterns in PER2::LUC mice. We confirmed that activity levels decrease during pregnancy and found that activity onset was delayed. Although SCN, but not arcuate nucleus, PER2::LUC period changed during late pregnancy, onset of locomotor activity did not correlate with SCN or arcuate nucleus PER2::LUC period.
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Affiliation(s)
- Alexandra M Yaw
- Department of Animal Science and the Reproductive and Developmental Science Program, Michigan State University, East Lansing, MI, USA
| | - Thu V Duong
- Department of Animal Science and the Reproductive and Developmental Science Program, Michigan State University, East Lansing, MI, USA
| | - Duong Nguyen
- Department of Animal Science and the Reproductive and Developmental Science Program, Michigan State University, East Lansing, MI, USA
| | - Hanne M Hoffmann
- Department of Animal Science and the Reproductive and Developmental Science Program, Michigan State University, East Lansing, MI, USA
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Sen A, Hoffmann HM. Role of core circadian clock genes in hormone release and target tissue sensitivity in the reproductive axis. Mol Cell Endocrinol 2020; 501:110655. [PMID: 31756424 PMCID: PMC6962569 DOI: 10.1016/j.mce.2019.110655] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 11/15/2019] [Accepted: 11/16/2019] [Indexed: 12/17/2022]
Abstract
Precise timing in hormone release from the hypothalamus, the pituitary and ovary is critical for fertility. Hormonal release patterns of the reproductive axis are regulated by a feedback loop within the hypothalamic-pituitary-gonadal (HPG) axis. The timing and rhythmicity of hormone release and tissue sensitivity in the HPG axis is regulated by circadian clocks located in the hypothalamus (suprachiasmatic nucleus, kisspeptin and GnRH neurons), the pituitary (gonadotrophs), the ovary (theca and granulosa cells), the testis (Leydig cells), as well as the uterus (endometrium and myometrium). The circadian clocks integrate environmental and physiological signals to produce cell endogenous rhythms generated by a transcriptional-translational feedback loop of transcription factors that are collectively called the "molecular clock". This review specifically focuses on the contribution of molecular clock transcription factors in regulating hormone release patterns in the reproductive axis, with an emphasis on the female reproductive system. Specifically, we discuss the contributions of circadian rhythms in distinct neuronal populations of the female hypothalamus, the molecular clock in the pituitary and its overall impact on female and male fertility.
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Affiliation(s)
- Aritro Sen
- Department of Animal Science and the Reproductive and Developmental Science Program, Michigan State University, East Lansing, MI, 48824, USA
| | - Hanne M Hoffmann
- Department of Animal Science and the Reproductive and Developmental Science Program, Michigan State University, East Lansing, MI, 48824, USA.
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Pan X, Taylor MJ, Cohen E, Hanna N, Mota S. Circadian Clock, Time-Restricted Feeding and Reproduction. Int J Mol Sci 2020; 21:ijms21030831. [PMID: 32012883 PMCID: PMC7038040 DOI: 10.3390/ijms21030831] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 12/29/2022] Open
Abstract
The goal of this review was to seek a better understanding of the function and differential expression of circadian clock genes during the reproductive process. Through a discussion of how the circadian clock is involved in these steps, the identification of new clinical targets for sleep disorder-related diseases, such as reproductive failure, will be elucidated. Here, we focus on recent research findings regarding circadian clock regulation within the reproductive system, shedding new light on circadian rhythm-related problems in women. Discussions on the roles that circadian clock plays in these reproductive processes will help identify new clinical targets for such sleep disorder-related diseases.
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Affiliation(s)
- Xiaoyue Pan
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York, NY 11501, USA
- Diabetes and Obesity Research Center, NYU Winthrop Hospital, Mineola, New York, NY 11501, USA
- Correspondence:
| | - Meredith J. Taylor
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York, NY 11501, USA
- Diabetes and Obesity Research Center, NYU Winthrop Hospital, Mineola, New York, NY 11501, USA
| | - Emma Cohen
- Diabetes and Obesity Research Center, NYU Winthrop Hospital, Mineola, New York, NY 11501, USA
| | - Nazeeh Hanna
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York, NY 11501, USA
- Department of Pediatrics, NYU Winthrop Hospital, Mineola, New York, NY 11501, USA
| | - Samantha Mota
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York, NY 11501, USA
- Diabetes and Obesity Research Center, NYU Winthrop Hospital, Mineola, New York, NY 11501, USA
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58
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Barredo CG, Gil-Marti B, Deveci D, Romero NM, Martin FA. Timing the Juvenile-Adult Neurohormonal Transition: Functions and Evolution. Front Endocrinol (Lausanne) 2020; 11:602285. [PMID: 33643219 PMCID: PMC7909313 DOI: 10.3389/fendo.2020.602285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 12/28/2020] [Indexed: 02/05/2023] Open
Abstract
Puberty and metamorphosis are two major developmental transitions linked to the reproductive maturation. In mammals and vertebrates, the central brain acts as a gatekeeper, timing the developmental transition through the activation of a neuroendocrine circuitry. In addition to reproduction, these neuroendocrine axes and the sustaining genetic network play additional roles in metabolism, sleep and behavior. Although neurohormonal axes regulating juvenile-adult transition have been classically considered the result of convergent evolution (i.e., analogous) between mammals and insects, recent findings challenge this idea, suggesting that at least some neuroendocrine circuits might be present in the common bilaterian ancestor Urbilateria. The initial signaling pathways that trigger the transition in different species appear to be of a single evolutionary origin and, consequently, many of the resulting functions are conserved with a few other molecular players being co-opted during evolution.
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Affiliation(s)
- Celia G. Barredo
- Molecular Physiology of Behavior Laboratory, Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain
| | - Beatriz Gil-Marti
- Molecular Physiology of Behavior Laboratory, Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain
| | - Derya Deveci
- Sartorius Netherlands BV, Amersfoor, Netherlands
| | - Nuria M. Romero
- Developmental Timing, Environment and Behaviors Laboratory, Institut Sophia Agrobiotech, Université Côte d’Azur-INRAE-CNRS-INSERM, Sophia Antipolis, France
- *Correspondence: Nuria M. Romero, ; Francisco A. Martin,
| | - Francisco A. Martin
- Molecular Physiology of Behavior Laboratory, Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain
- *Correspondence: Nuria M. Romero, ; Francisco A. Martin,
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59
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Kim D, Jang S, Kim J, Park I, Ku K, Choi M, Lee S, Heo WD, Son GH, Choe HK, Kim K. Kisspeptin Neuron-Specific and Self-Sustained Calcium Oscillation in the Hypothalamic Arcuate Nucleus of Neonatal Mice: Regulatory Factors of its Synchronization. Neuroendocrinology 2020; 110:1010-1027. [PMID: 31935735 PMCID: PMC7592953 DOI: 10.1159/000505922] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 01/11/2020] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Synchronous and pulsatile neural activation of kisspeptin neurons in the arcuate nucleus (ARN) are important components of the gonadotropin-releasing hormone pulse generator, the final common pathway for central regulation of mammalian reproduction. However, whether ARN kisspeptin neurons can intrinsically generate self-sustained synchronous oscillations from the early neonatal period and how they are regulated remain unclear. OBJECTIVE This study aimed to examine the endogenous rhythmicity of ARN kisspeptin neurons and its neural regulation using a neonatal organotypic slice culture model. METHODS We monitored calcium (Ca2+) dynamics in real-time from individual ARN kisspeptin neurons in neonatal organotypic explant cultures of Kiss1-IRES-Cre mice transduced with genetically encoded Ca2+ indicators. Pharmacological approaches were employed to determine the regulations of kisspeptin neuron-specific Ca2+ oscillations. A chemogenetic approach was utilized to assess the contribution of ARN kisspeptin neurons to the population dynamics. RESULTS ARN kisspeptin neurons in neonatal organotypic cultures exhibited a robust synchronized Ca2+ oscillation with a period of approximately 3 min. Kisspeptin neuron-specific Ca2+ oscillations were dependent on voltage-gated sodium channels and regulated by endoplasmic reticulum-dependent Ca2+ homeostasis. Chemogenetic inhibition of kisspeptin neurons abolished synchronous Ca2+ oscillations, but the autocrine actions of the neuropeptides were marginally effective. Finally, neonatal ARN kisspeptin neurons were regulated by N-methyl-D-aspartate and gamma-aminobutyric acid receptor-mediated neurotransmission. CONCLUSION These data demonstrate that ARN kisspeptin neurons in organotypic cultures can generate synchronized and self-sustained Ca2+ oscillations. These oscillations controlled by multiple regulators within the ARN are a novel ultradian rhythm generator that is active during the early neonatal period.
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Affiliation(s)
- Doyeon Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
- Interdisciplinary Program in Neuroscience, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - Sangwon Jang
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Jeongah Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Inah Park
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Kyojin Ku
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Mijung Choi
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Sukwon Lee
- Department of Neural Development and Disease, Korea Brain Research Institute, Daegu, Republic of Korea
| | - Won Do Heo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Gi Hoon Son
- Department of Biomedical Sciences, College of Medicine, Korea University, Seoul, Republic of Korea
| | - Han Kyoung Choe
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Kyungjin Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea,
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60
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Wang L, Moenter SM. Differential Roles of Hypothalamic AVPV and Arcuate Kisspeptin Neurons in Estradiol Feedback Regulation of Female Reproduction. Neuroendocrinology 2020; 110:172-184. [PMID: 31466075 PMCID: PMC7047625 DOI: 10.1159/000503006] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 08/28/2019] [Indexed: 11/19/2022]
Abstract
Mammalian reproductive function includes puberty onset and completion, reproductive cyclicity, steroidogenesis, gametogenesis, fertilization, pregnancy, and lactation; all are indispensable to perpetuate species. Reproductive cycles are critical for providing the hormonal milieu needed for follicular development and maturation of eggs, but cycles, in and of themselves, do not guarantee ovulation will occur. Here, we review the roles in female reproductive neuroendocrine function of two hypothalamic populations that produce the neuropeptide kisspeptin, demonstrating distinct roles in maintaining cycles and ovulation.
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Affiliation(s)
- Luhong Wang
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Suzanne M Moenter
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA,
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA,
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, USA,
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61
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Rønnekleiv OK, Qiu J, Kelly MJ. Arcuate Kisspeptin Neurons Coordinate Reproductive Activities with Metabolism. Semin Reprod Med 2019; 37:131-140. [PMID: 31869841 DOI: 10.1055/s-0039-3400251] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Hypothalamic control of fertility is the quintessential homeostatic function. However, fertility is metabolically demanding; so, there must be coordination between energy states and reproductive functions. Because gonadotropin-releasing hormone (GnRH) neurons are devoid of many of the critical metabolic hormone receptors for sensing nutrient levels, it has long been recognized that the sensing of energy stores had to be done by neurons presynaptic to GnRH neurons. Some of the obvious players have been the anorexigenic proopiomelanocortin (POMC) and orexigenic neuropeptide Y (NPY)/agouti-related peptide (AgRP) neurons, both of which are in close apposition to the median eminence, a circumventricular organ. Indeed, POMC and NPY/AgRP neurons are inversely regulated by glucose and metabolic hormones including insulin and leptin. However, their synaptic connections with GnRH neurons are sparse and/or GnRH neurons are lacking the postsynaptic receptors to mediate the appropriate physiological response. Kisspeptin neurons were discovered in the early part of this century and subsequently shown to project to and control GnRH neuronal excitability. In fact, more recently the arcuate kisspeptin neurons have been identified as the command neurons driving pulsatile release of GnRH. Subsequently, it was shown that arcuate kisspeptin neurons express not only steroid hormone receptors but also metabolic hormone receptors such that similar to POMC neurons, they are excited by insulin and leptin. Therefore, based on the premise that arcuate kisspeptin neurons are the key neurons coordinating energy states with reproduction, we will review not only how these vital neurons control pulsatile GnRH release but how they control energy homeostasis through their synaptic connections with POMC and NPY/AgRP neurons and ultimately how E2 can regulate their excitability.
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Affiliation(s)
- Oline K Rønnekleiv
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon.,Division of Neuroscience, National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon
| | - Jian Qiu
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon
| | - Martin J Kelly
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon.,Division of Neuroscience, National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon
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Silva CC, Cortés GD, Javier CY, Flores A, Domínguez R. A neural circadian signal essential for ovulation is generated in the suprachiasmatic nucleus during each stage of the oestrous cycle. Exp Physiol 2019; 105:258-269. [PMID: 31769118 DOI: 10.1113/ep087942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 11/25/2019] [Indexed: 12/31/2022]
Abstract
NEW FINDINGS What is the central question of this study? Is the suprachiasmatic nucleus the structure that generates the neural circadian signals that occur during every stage of the oestrous cycle, not only pro-oestrus, and are these signals essential for proper regulation of ovulation? What is the main finding and its importance? Transient inhibition of Na+ -dependent action potentials in the suprachiasmatic nucleus by tetrodotoxin microinjection at 14.00 h inhibits ovulation irrespective of the stage of the oestrous cycle at which the procedure is performed. Microinjection of saline solution into the suprachiasmatic nucleus has a disruptive effect on ovulation that depends on the stage of the cycle at which it is administered. ABSTRACT Reproduction is a highly timed process that depends on both the reproductive and circadian systems. The core oscillator of the latter resides at the suprachiasmatic nuclei (SCN) and it is pivotal for the regulation of the pro-oestrus pre-ovulatory surge of gonadotropins in females. There is evidence to suggest that this system may be involved in the regulation of neuroendocrine events that are essential for ovulation and that occur prior to pro-oestrus. We explored this possibility by transiently inactivating the SCN. Female rats were implanted with guide cannulas aimed at the SCN. After recovery of the oestrous cycle, animals were injected with tetrodotoxin (TTX), artificial cerebrospinal fluid (ACSF) or saline solution while freely moving. Injections were performed at 14.00 h of each stage of the oestrous cycle. Animals were killed on the next predicted oestrus day, the number of ova shed was counted and intact rats at oestrus stage were used as absolute control. ACSF did not modify ovulation. Saline solution blocked ovulation in oestrus- and dioestrus-injected rats. Irrespectively of the stage of the oestrous cycle, TTX blocked ovulation. These results lead us to suggest that a neural circadian signal, pivotal for triggering the gonadotropin pre-ovulatory surge, arises from the SCN during the critical window of pro-oestrus. We also suggest that a similar signal, needed for the regulation of other events that are indispensable for proper regulation of ovulation, is also generated in this nucleus during the other stages of the cycle at a similar time.
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Affiliation(s)
- Carlos-Camilo Silva
- Chronobiology of Reproduction Research Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México.,Developmental Biology Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México
| | - Georgina Daniela Cortés
- Chronobiology of Reproduction Research Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México
| | - Cintia Yolanda Javier
- Chronobiology of Reproduction Research Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México
| | - Angélica Flores
- Chronobiology of Reproduction Research Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México.,Developmental Biology Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México
| | - Roberto Domínguez
- Chronobiology of Reproduction Research Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México.,Developmental Biology Lab, Biology of Reproduction Research Unit, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, México City, México
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Cedernaes J, Waldeck N, Bass J. Neurogenetic basis for circadian regulation of metabolism by the hypothalamus. Genes Dev 2019; 33:1136-1158. [PMID: 31481537 PMCID: PMC6719618 DOI: 10.1101/gad.328633.119] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Circadian rhythms are driven by a transcription-translation feedback loop that separates anabolic and catabolic processes across the Earth's 24-h light-dark cycle. Central pacemaker neurons that perceive light entrain a distributed clock network and are closely juxtaposed with hypothalamic neurons involved in regulation of sleep/wake and fast/feeding states. Gaps remain in identifying how pacemaker and extrapacemaker neurons communicate with energy-sensing neurons and the distinct role of circuit interactions versus transcriptionally driven cell-autonomous clocks in the timing of organismal bioenergetics. In this review, we discuss the reciprocal relationship through which the central clock drives appetitive behavior and metabolic homeostasis and the pathways through which nutrient state and sleep/wake behavior affect central clock function.
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Affiliation(s)
- Jonathan Cedernaes
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Nathan Waldeck
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Joseph Bass
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
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Velasco I, León S, Barroso A, Ruiz-Pino F, Heras V, Torres E, León M, Ruohonen ST, García-Galiano D, Romero-Ruiz A, Sánchez-Garrido MA, Ohlsson C, Castellano JM, Roa J, Poutanen M, Pinilla L, Vázquez MJ, Tena-Sempere M. Gonadal hormone-dependent vs. -independent effects of kisspeptin signaling in the control of body weight and metabolic homeostasis. Metabolism 2019; 98:84-94. [PMID: 31226351 DOI: 10.1016/j.metabol.2019.06.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/31/2019] [Accepted: 06/12/2019] [Indexed: 12/15/2022]
Abstract
BACKGROUND Kisspeptins, encoded by Kiss1, have emerged as essential regulators of puberty and reproduction by primarily acting on GnRH neurons, via their canonical receptor, Gpr54. Mounting, as yet fragmentary, evidence strongly suggests that kisspeptin signaling may also participate in the control of key aspects of body energy and metabolic homeostasis. However, characterization of such metabolic dimension of kisspeptins remains uncomplete, without an unambiguous discrimination between the primary metabolic actions of kisspeptins vs. those derived from their ability to stimulate the secretion of gonadal hormones, which have distinct metabolic actions on their own. In this work, we aimed to tease apart primary vs. secondary effects of kisspeptins in the control of key aspects of metabolic homeostasis using genetic models of impaired kisspeptin signaling and/or gonadal hormone status. METHODS Body weight (BW) gain and composition, food intake and key metabolic parameters, including glucose tolerance, were comparatively analyzed, in lean and obesogenic conditions, in mice lacking kisspeptin signaling due to global inactivation of Gpr54 (displaying profound hypogonadism; Gpr54-/-) vs. Gpr54 null mice with selective re-introduction of Gpr54 expression only in GnRH cells (Gpr54-/-Tg), where kisspeptin signaling elsewhere than in GnRH neurons is ablated but gonadal function is preserved. RESULTS In male mice, global elimination of kisspeptin signaling resulted in decreased BW, feeding suppression and increased adiposity, without overt changes in glucose tolerance, whereas Gpr54-/- female mice displayed enhanced BW gain at adulthood, increased adiposity and perturbed glucose tolerance, despite reduced food intake. Gpr54-/-Tg rescued mice showed altered postnatal BW gain in males and mildly perturbed glucose tolerance in females, with intermediate phenotypes between control and global KO animals. Yet, body composition and leptin levels were similar to controls in gonadal-rescued mice. Exposure to obesogenic insults, such as high fat diet (HFD), resulted in exaggerated BW gain and adiposity in global Gpr54-/- mice of both sexes, and worsening of glucose tolerance, especially in females. Yet, while rescued Gpr54-/-Tg males displayed intermediate BW gain and feeding profiles and impaired glucose tolerance, rescued Gpr54-/-Tg females behaved as controls, except for a modest deterioration of glucose tolerance after ovariectomy. CONCLUSION Our data support a global role of kisspeptin signaling in the control of body weight and metabolic homeostasis, with a dominant contribution of gonadal hormone-dependent actions. However, our results document also discernible primary effects of kisspeptin signaling in the regulation of body weight gain, feeding and responses to obesogenic insults, which occur in a sexually-dimorphic manner. SUMMARY OF TRANSLATIONAL RELEVANCE Kisspeptins, master regulators of reproduction, may also participate in the control of key aspects of body energy and metabolic homeostasis; yet, the nature of such metabolic actions remains debatable, due in part to the fact that kisspeptins modulate gonadal hormones, which have metabolic actions on their own. By comparing the metabolic profiles of two mouse models with genetic inactivation of kisspeptin signaling but different gonadal status (hypogonadal vs. preserved gonadal function), we provide herein a systematic dissection of gonadal-dependent vs. -independent metabolic actions of kisspeptins. Our data support a global role of kisspeptin signaling in the control of body weight and metabolic homeostasis, with a dominant contribution of gonadal hormone-dependent actions. However, our results document also discernible primary effects of kisspeptin signaling in the regulation of body weight gain, feeding and responses to obesogenic insults, which occur in a sexually-dimorphic manner. These data pave the way for future analyses addressing the eventual contribution of altered kisspeptin signaling in the development of metabolic alterations, especially in conditions linked to reproductive dysfunction.
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Affiliation(s)
- Inmaculada Velasco
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Silvia León
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain.
| | - Alexia Barroso
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Francisco Ruiz-Pino
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Violeta Heras
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Encarnación Torres
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - María León
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Suvi T Ruohonen
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine and Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - David García-Galiano
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Antonio Romero-Ruiz
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Miguel A Sánchez-Garrido
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Claes Ohlsson
- Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Juan M Castellano
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Juan Roa
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Matti Poutanen
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine and Turku Center for Disease Modeling, University of Turku, Turku, Finland; Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Leonor Pinilla
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - María J Vázquez
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain
| | - Manuel Tena-Sempere
- Instituto Maimónides de Investigation Biomédica de Córdoba (IMIBIC), 14004 Córdoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14004 Córdoba, Spain; Hospital Universitario Reina Sofia, 14004 Córdoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 14004 Córdoba, Spain; Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine and Turku Center for Disease Modeling, University of Turku, Turku, Finland.
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Karatsoreos IN. Circadian Regulation of the Brain and Behavior: A Neuroendocrine Perspective. Curr Top Behav Neurosci 2019; 43:323-351. [PMID: 31586337 DOI: 10.1007/7854_2019_115] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Neuroendocrine systems are key regulators of brain and body functions, providing an important nexus between internal states and the external world, which then modulates appropriate behavioral outputs. Circadian (daily) rhythms are endogenously generated rhythms of approximately 24 h that help to synchronize internal physiological processes and behavioral states to the external environmental light-dark cycle. Given the importance of timing (hours, days, annual) in many different neuroendocrine axes, understanding how the circadian timing system regulates neuroendocrine function is particularly critical. Similarly, neuroendocrine signals can significantly affect circadian timing, and understanding these mechanisms can provide insights into general concepts of neuroendocrine regulation of brain circuits and behavior. This chapter will review the circadian timing system and its control of two key neuroendocrine systems: the hypothalamic-pituitary-gonadal (HPG) axis and the hypothalamic-pituitary-adrenal (HPA) axis. It will also discuss how outputs from these axes feedback to affect the circadian clock. Given that disruption of circadian timing is a central component of many mental and physical health conditions and that neuroendocrine function is similarly implicated in many of the same conditions, understanding these links will help illuminate potentially shared causality and perhaps lead to a better understanding of how to manipulate these systems when they begin to malfunction.
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Affiliation(s)
- Ilia N Karatsoreos
- Department of Integrative Physiology and Neuroscience, Washington State University, Pullman, WA, USA.
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