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Schöllhorn I, Stefani O, Lucas RJ, Spitschan M, Epple C, Cajochen C. The Impact of Pupil Constriction on the Relationship Between Melanopic EDI and Melatonin Suppression in Young Adult Males. J Biol Rhythms 2024; 39:282-294. [PMID: 38348477 DOI: 10.1177/07487304241226466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
The pupil modulates the amount of light that reaches the retina. Not only luminance but also the spectral distribution defines the pupil size. Previous research has identified steady-state pupil size and melatonin attenuation to be predominantly driven by melanopsin, which is expressed by a unique subgroup of intrinsically photosensitive retinal ganglion cells (ipRGCs) that are sensitive to short-wavelength light (~480 nm). Here, we aimed to selectively target the melanopsin system during the evening, while measuring steady-state pupil size and melatonin concentrations under commonly experienced evening light levels (<90 lx). Therefore, we used a five-primary display prototype to generate light conditions that were matched in terms of L-, M-, and S-cone-opic irradiances, but with high and low melanopic irradiances (~3-fold difference). Seventy-two healthy, male participants completed a 2-week study protocol. The volunteers were assigned to one of the four groups that differed in luminance levels (27-285 cd/m2). Within the four groups, each volunteer was exposed to a low melanopic (LM) and a high melanopic (HM) condition. The two 17-h study protocols comprised 3.5 h of light exposure starting 4 h before habitual bedtime. Median pupil size was significantly smaller during HM than LM in all four light intensity groups. In addition, we observed a significant correlation between melanopic weighted corneal illuminance (melanopic equivalent daylight illuminance [mEDI]) and pupil size, such that higher mEDI values were associated with smaller pupil size. Using pupil size to estimate retinal irradiance showed a qualitatively similar goodness of fit as mEDI for predicting melatonin suppression. Based on our results here, it remains appropriate to use melanopic irradiance measured at eye level when comparing light-dependent effects on evening melatonin concentrations in healthy young people at rather low light levels.
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Affiliation(s)
- Isabel Schöllhorn
- Centre for Chronobiology, Psychiatric Hospital, University of Basel, Basel, Switzerland
- Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel, Basel, Switzerland
| | - Oliver Stefani
- Centre for Chronobiology, Psychiatric Hospital, University of Basel, Basel, Switzerland
- Lucerne University of Applied Sciences and Arts, Lucerne, Switzerland
| | - Robert J Lucas
- Centre for Biological Timing, School of Biology, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Manuel Spitschan
- Translational Sensory & Circadian Neuroscience, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
- Chronobiology & Health, Technical University of Munich, Munich, Germany
- TUM Institute for Advanced Study (TUM-IAS), Technical University of Munich, Munich, Germany
| | - Christian Epple
- Centre for Chronobiology, Psychiatric Hospital, University of Basel, Basel, Switzerland
| | - Christian Cajochen
- Centre for Chronobiology, Psychiatric Hospital, University of Basel, Basel, Switzerland
- Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel, Basel, Switzerland
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Franke K, Cai C, Ponder K, Fu J, Sokoloski S, Berens P, Tolias AS. Asymmetric distribution of color-opponent response types across mouse visual cortex supports superior color vision in the sky. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.01.543054. [PMID: 37333280 PMCID: PMC10274736 DOI: 10.1101/2023.06.01.543054] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Color is an important visual feature that informs behavior, and the retinal basis for color vision has been studied across various vertebrate species. While many studies have investigated how color information is processed in visual brain areas of primate species, we have limited understanding of how it is organized beyond the retina in other species, including most dichromatic mammals. In this study, we systematically characterized how color is represented in the primary visual cortex (V1) of mice. Using large-scale neuronal recordings and a luminance and color noise stimulus, we found that more than a third of neurons in mouse V1 are color-opponent in their receptive field center, while the receptive field surround predominantly captures luminance contrast. Furthermore, we found that color-opponency is especially pronounced in posterior V1 that encodes the sky, matching the statistics of natural scenes experienced by mice. Using unsupervised clustering, we demonstrate that the asymmetry in color representations across cortex can be explained by an uneven distribution of green-On/UV-Off color-opponent response types that are represented in the upper visual field. Finally, a simple model with natural scene-inspired parametric stimuli shows that green-On/UV-Off color-opponent response types may enhance the detection of "predatory"-like dark UV-objects in noisy daylight scenes. The results from this study highlight the relevance of color processing in the mouse visual system and contribute to our understanding of how color information is organized in the visual hierarchy across species.
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Calanni JS, Aranda ML, Dieguez HH, Dorfman D, Schmidt TM, Rosenstein RE. An ethologically relevant paradigm to assess visual contrast sensitivity in rodents. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.05.583559. [PMID: 38496475 PMCID: PMC10942302 DOI: 10.1101/2024.03.05.583559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
In the animal kingdom, threat information is perceived mainly through vision. The subcortical visual pathway plays a critical role in the rapid processing of visual information-induced fear, and triggers a response. Looming-evoked behavior in rodents, mimicking response to aerial predators, allowed identify the neural circuitry underlying instinctive defensive behaviors; however, the influence of disk/background contrast on the looming-induced behavioral response has not been examined, either in rats or mice. We studied the influence of the dark disk/gray background contrast in the type of rat and mouse defensive behavior in the looming arena, and we showed that rat and mouse response as a function of disk/background contrast adjusted to a sigmoid-like relationship. Both sex and age biased the contrast-dependent response, which was dampened in rats submitted to retinal unilateral or bilateral ischemia. Moreover, using genetically manipulated mice, we showed that the three type of photoresponsive retinal cells (i.e., cones, rods, and intrinsically photoresponsive retinal ganglion cells (ipRGCs)), participate in the contrast-dependent response, following this hierarchy: cones ˃> rods ˃>>ipRGCs. The cone and rod involvement was confirmed using a mouse model of unilateral non-exudative age-related macular degeneration, which only damages canonical photoreceptors and significantly decreased the contrast sensitivity in the looming arena.
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4
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Dauchy RT, Hanifin JP, Brainard GC, Blask DE. Light: An Extrinsic Factor Influencing Animal-based Research. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2024; 63:116-147. [PMID: 38211974 PMCID: PMC11022951 DOI: 10.30802/aalas-jaalas-23-000089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/26/2023] [Accepted: 10/28/2023] [Indexed: 01/13/2024]
Abstract
Light is an environmental factor that is extrinsic to animals themselves and that exerts a profound influence on the regulation of circadian, neurohormonal, metabolic, and neurobehavioral systems of all animals, including research animals. These widespread biologic effects of light are mediated by distinct photoreceptors-rods and cones that comprise the conventional visual system and melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) of the nonvisual system that interact with the rods and cones. The rods and cones of the visual system, along with the ipRGCs of the nonvisual system, are species distinct in terms of opsins and opsin concentrations and interact with one another to provide vision and regulate circadian rhythms of neurohormonal and neurobehavioral responses to light. Here, we review a brief history of lighting technologies, the nature of light and circadian rhythms, our present understanding of mammalian photoreception, and current industry practices and standards. We also consider the implications of light for vivarium measurement, production, and technological application and provide simple recommendations on artificial lighting for use by regulatory authorities, lighting manufacturers, designers, engineers, researchers, and research animal care staff that ensure best practices for optimizing animal health and well-being and, ultimately, improving scientific outcomes.
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Key Words
- blad, blue-enriched led light at daytime
- clock, circadian locomotor output kaput
- cct, correlated color temperature
- cwf, cool white fluorescent
- ign, intergeniculate nucleus
- iprgc, intrinsically photosensitive retinal ganglion cell
- hiomt, hydroxyindole-o-methyltransferase
- k, kelvin temperature
- lan, light at night
- led, light-emitting diode
- lgn, lateral geniculate nucleus
- plr, pupillary light reflex
- pot, primary optic tract
- rht, retinohypothalamic tract
- scn, suprachiasmatic nuclei
- spd, spectral power distribution.
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Affiliation(s)
- Robert T Dauchy
- Department of Structural and Cellular Biology, Laboratory of Chrono-Neuroendocrine Oncology, Tulane University School of Medicine, New Orleans, Louisiana;,
| | - John P Hanifin
- Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - George C Brainard
- Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - David E Blask
- Department of Structural and Cellular Biology, Laboratory of Chrono-Neuroendocrine Oncology, Tulane University School of Medicine, New Orleans, Louisiana
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Lucas RJ, Allen AE, Brainard GC, Brown TM, Dauchy RT, Didikoglu A, Do MTH, Gaskill BN, Hattar S, Hawkins P, Hut RA, McDowell RJ, Nelson RJ, Prins JB, Schmidt TM, Takahashi JS, Verma V, Voikar V, Wells S, Peirson SN. Recommendations for measuring and standardizing light for laboratory mammals to improve welfare and reproducibility in animal research. PLoS Biol 2024; 22:e3002535. [PMID: 38470868 DOI: 10.1371/journal.pbio.3002535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024] Open
Abstract
Light enables vision and exerts widespread effects on physiology and behavior, including regulating circadian rhythms, sleep, hormone synthesis, affective state, and cognitive processes. Appropriate lighting in animal facilities may support welfare and ensure that animals enter experiments in an appropriate physiological and behavioral state. Furthermore, proper consideration of light during experimentation is important both when it is explicitly employed as an independent variable and as a general feature of the environment. This Consensus View discusses metrics to use for the quantification of light appropriate for nonhuman mammals and their application to improve animal welfare and the quality of animal research. It provides methods for measuring these metrics, practical guidance for their implementation in husbandry and experimentation, and quantitative guidance on appropriate light exposure for laboratory mammals. The guidance provided has the potential to improve data quality and contribute to reduction and refinement, helping to ensure more ethical animal use.
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Affiliation(s)
- Robert J Lucas
- Centre for Biological Timing, School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Annette E Allen
- Centre for Biological Timing, School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - George C Brainard
- Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Timothy M Brown
- Centre for Biological Timing, School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Robert T Dauchy
- Department of Structural and Cellular Biology, Tulane University School of Medicine, Tulane, Louisiana, United States of America
| | - Altug Didikoglu
- Department of Neuroscience, Izmir Institute of Technology, Gülbahçe, Urla, Izmir, Turkey
| | - Michael Tri H Do
- F.M. Kirby Neurobiology Center and Department of Neurology, Boston Children's Hospital and Harvard Medical School, Center for Life Science, Boston, Massachusetts, United States of America
| | - Brianna N Gaskill
- Novartis Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Samer Hattar
- Section on Light and Circadian Rhythms (SLCR), National Institute of Mental Health, John Edward Porter Neuroscience Research Center, Bethesda, Maryland, United States of America
| | | | - Roelof A Hut
- Chronobiology Unit, Groningen Institute of Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Richard J McDowell
- Centre for Biological Timing, School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Randy J Nelson
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia, United States of America
| | - Jan-Bas Prins
- The Francis Crick Institute, London, United Kingdom
- Leiden University Medical Centre, Leiden, the Netherlands
| | - Tiffany M Schmidt
- Department of Neurobiology, Northwestern University, Evanston, Illinois, United States of America
| | - Joseph S Takahashi
- Department of Neuroscience, Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Vandana Verma
- NASA Ames Research Center, Space Biosciences Division, Moffett Field, California, United States of America
| | - Vootele Voikar
- Laboratory Animal Center and Neuroscience Center, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Sara Wells
- The Mary Lyon Centre, MRC Harwell, Harwell Campus, Oxfordshire, United Kingdom
| | - Stuart N Peirson
- Sleep and Circadian Neuroscience Institute (SCNi), Kavli Institute for Nanoscience Discovery, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
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Blume C, Cajochen C, Schöllhorn I, Slawik HC, Spitschan M. Effects of calibrated blue-yellow changes in light on the human circadian clock. Nat Hum Behav 2024; 8:590-605. [PMID: 38135734 PMCID: PMC10963261 DOI: 10.1038/s41562-023-01791-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 11/16/2023] [Indexed: 12/24/2023]
Abstract
Evening exposure to short-wavelength light can affect the circadian clock, sleep and alertness. Intrinsically photosensitive retinal ganglion cells expressing melanopsin are thought to be the primary drivers of these effects. Whether colour-sensitive cones also contribute is unclear. Here, using calibrated silent-substitution changes in light colour along the blue-yellow axis, we investigated whether mechanisms of colour vision affect the human circadian system and sleep. In a 32.5-h repeated within-subjects protocol, 16 healthy participants were exposed to three different light scenarios for 1 h starting 30 min after habitual bedtime: baseline control condition (93.5 photopic lux), intermittently flickering (1 Hz, 30 s on-off) yellow-bright light (123.5 photopic lux) and intermittently flickering blue-dim light (67.0 photopic lux), all calibrated to have equal melanopsin excitation. We did not find conclusive evidence for differences between the three lighting conditions regarding circadian melatonin phase delays, melatonin suppression, subjective sleepiness, psychomotor vigilance or sleep.The Stage 1 protocol for this Registered Report was accepted in principle on 9 September 2020. The protocol, as accepted by the journal, can be found at https://doi.org/10.6084/m9.figshare.13050215.v1 .
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Affiliation(s)
- Christine Blume
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland.
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland.
- Department of Biomedicine, University of Basel, Basel, Switzerland.
| | - Christian Cajochen
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
| | - Isabel Schöllhorn
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
| | - Helen C Slawik
- Psychiatric Hospital of the University of Basel, Basel, Switzerland
| | - Manuel Spitschan
- Translational Sensory and Circadian Neuroscience, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.
- TUM Department Health and Sport Sciences, TUM School of Medicine and Health, Technical University of Munich, Munich, Germany.
- TUM Institute for Advanced Study (TUM-IAS), Technical University of Munich, Garching, Germany.
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7
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Feigl B, Lewis SJG, Rawashdeh O. Targeting sleep and the circadian system as a novel treatment strategy for Parkinson's disease. J Neurol 2024; 271:1483-1491. [PMID: 37943299 PMCID: PMC10896880 DOI: 10.1007/s00415-023-12073-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/12/2023] [Accepted: 10/18/2023] [Indexed: 11/10/2023]
Abstract
There is a growing appreciation of the wide range of sleep-wake disturbances that occur frequently in Parkinson's disease. These are known to be associated with a range of motor and non-motor symptoms and significantly impact not only on the quality of life of the patient, but also on their bed partner. The underlying causes for fragmented sleep and daytime somnolence are no doubt multifactorial but there is clear evidence for circadian disruption in Parkinson's disease. This appears to be occurring not only as a result of the neuropathological changes that occur across a distributed neural network, but even down to the cellular level. Such observations indicate that circadian changes may in fact be a driver of neurodegeneration, as well as a cause for some of the sleep-wake symptoms observed in Parkinson's disease. Thus, efforts are now required to evaluate approaches including the prescription of precision medicine to modulate photoreceptor activation ratios that reflect daylight inputs to the circadian pacemaker, the use of small molecules to target clock genes, the manipulation of orexin pathways that could help restore the circadian system, to offer novel symptomatic and novel disease modifying strategies.
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Affiliation(s)
- Beatrix Feigl
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD, 4059, Australia
- School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD, 4059, Australia
- Queensland Eye Institute, South Brisbane, QLD, 4101, Australia
| | - Simon J G Lewis
- Parkinson's Disease Research Clinic, Brain and Mind Centre, School of Medical Sciences, University of Sydney, Camperdown, NSW, 2006, Australia.
| | - Oliver Rawashdeh
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD, 4072, Australia
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8
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Springer MS, Emerling CA, Gatesy J. Three Blind Moles: Molecular Evolutionary Insights on the Tempo and Mode of Convergent Eye Degeneration in Notoryctes typhlops (Southern Marsupial Mole) and Two Chrysochlorids (Golden Moles). Genes (Basel) 2023; 14:2018. [PMID: 38002961 PMCID: PMC10671557 DOI: 10.3390/genes14112018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 10/20/2023] [Accepted: 10/25/2023] [Indexed: 11/26/2023] Open
Abstract
Golden moles (Chrysochloridae) and marsupial moles (Notoryctidae) are textbook examples of convergent evolution. Both taxa are highly adapted to subterranean lifestyles and have powerful limbs for digging through the soil/sand, ears that are adapted for low-frequency hearing, vestigial eyes that are covered by skin and fur, and the absence of optic nerve connections between the eyes and the brain. The eyes of marsupial moles also lack a lens as well as retinal rods and cones. Two hypotheses have been proposed to account for the greater degeneracy of the eyes of marsupial moles than golden moles. First, marsupial moles may have had more time to adapt to their underground habitat than other moles. Second, the eyes of marsupial moles may have been rapidly and recently vestigialized to (1) reduce the injurious effects of sand getting into the eyes and (2) accommodate the enlargement of lacrimal glands that keep the nasal cavity moist and prevent the entry of sand into the nasal passages during burrowing. Here, we employ molecular evolutionary methods on DNA sequences for 38 eye genes, most of which are eye-specific, to investigate the timing of relaxed selection (=neutral evolution) for different groups of eye-specific genes that serve as proxies for distinct functional components of the eye (rod phototransduction, cone phototransduction, lens/cornea). Our taxon sampling included 12 afrothere species, of which two are golden moles (Amblysomus hottentotus, Chrysochloris asiatica), and 28 marsupial species including two individuals of the southern marsupial mole (Notoryctes typhlops). Most of the sequences were mined from databases, but we also provide new genome data for A. hottentotus and one of the two N. typhlops individuals. Even though the eyes of golden moles are less degenerate than the eyes of marsupial moles, there are more inactivating mutations (e.g., frameshift indels, premature stop codons) in their cone phototransduction and lens/cornea genes than in orthologous genes of the marsupial mole. We estimate that cone phototransduction recovery genes were inactivated first in each group, followed by lens/cornea genes and then cone phototransduction activation genes. All three groups of genes were inactivated earlier in golden moles than in marsupial moles. For the latter, we estimate that lens/cornea genes were inactivated ~17.8 million years ago (MYA) when stem notoryctids were burrowing in the soft soils of Australian rainforests. Selection on phototransduction activation genes was relaxed much later (5.38 MYA), during the early stages of Australia's aridification that produced coastal sand plains and eventually sand dunes. Unlike cone phototransduction activation genes, rod phototransduction activation genes are intact in both golden moles and one of the two individuals of N. typhlops. A second marsupial mole individual has just a single inactivating mutation in one of the rod phototransduction activation genes (PDE6B). One explanation for this result is that some rod phototransduction activation genes are pleiotropic and are expressed in extraocular tissues, possibly in conjunction with sperm thermotaxis.
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Affiliation(s)
- Mark S. Springer
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA 92521, USA
| | | | - John Gatesy
- Division of Vertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA;
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9
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Pan D, Wang Z, Chen Y, Cao J. Melanopsin-mediated optical entrainment regulates circadian rhythms in vertebrates. Commun Biol 2023; 6:1054. [PMID: 37853054 PMCID: PMC10584931 DOI: 10.1038/s42003-023-05432-7] [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: 07/08/2023] [Accepted: 10/09/2023] [Indexed: 10/20/2023] Open
Abstract
Melanopsin (OPN4) is a light-sensitive protein that plays a vital role in the regulation of circadian rhythms and other nonvisual functions. Current research on OPN4 has focused on mammals; more evidence is needed from non-mammalian vertebrates to fully assess the significance of the non-visual photosensitization of OPN4 for circadian rhythm regulation. There are species differences in the regulatory mechanisms of OPN4 for vertebrate circadian rhythms, which may be due to the differences in the cutting variants, tissue localization, and photosensitive activation pathway of OPN4. We here summarize the distribution of OPN4 in mammals, birds, and teleost fish, and the classical excitation mode for the non-visual photosensitive function of OPN4 in mammals is discussed. In addition, the role of OPN4-expressing cells in regulating circadian rhythm in different vertebrates is highlighted, and the potential rhythmic regulatory effects of various neuropeptides or neurotransmitters expressed in mammalian OPN4-expressing ganglion cells are summarized among them.
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Affiliation(s)
- Deng Pan
- Laboratory of Anatomy of Domestic Animals, National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Haidian, 100193, Beijing, China
| | - Zixu Wang
- Laboratory of Anatomy of Domestic Animals, National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Haidian, 100193, Beijing, China
| | - Yaoxing Chen
- Laboratory of Anatomy of Domestic Animals, National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Haidian, 100193, Beijing, China
| | - Jing Cao
- Laboratory of Anatomy of Domestic Animals, National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Haidian, 100193, Beijing, China.
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10
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Paparella I, Campbell I, Sharifpour R, Beckers E, Berger A, Aizpurua JFB, Koshmanova E, Mortazavi N, Talwar P, Degueldre C, Lamalle L, Sherif S, Phillips C, Maquet P, Vandewalle G. Light modulates task-dependent thalamo-cortical connectivity during an auditory attentional task. Commun Biol 2023; 6:945. [PMID: 37714936 PMCID: PMC10504287 DOI: 10.1038/s42003-023-05337-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 09/08/2023] [Indexed: 09/17/2023] Open
Abstract
Exposure to blue wavelength light stimulates alertness and performance by modulating a widespread set of task-dependent cortical and subcortical areas. How light affects the crosstalk between brain areas to trigger this stimulating effect is not established. Here we record the brain activity of 19 healthy young participants (24.05±2.63; 12 women) while they complete an auditory attentional task in darkness or under an active (blue-enriched) or a control (orange) light, in an ultra-high-field 7 Tesla MRI scanner. We test if light modulates the effective connectivity between an area of the posterior associative thalamus, encompassing the pulvinar, and the intraparietal sulcus (IPS), key areas in the regulation of attention. We find that only the blue-enriched light strengthens the connection from the posterior thalamus to the IPS. To the best of our knowledge, our results provide the first empirical data supporting that blue wavelength light affects ongoing non-visual cognitive activity by modulating task-dependent information flow from subcortical to cortical areas.
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Affiliation(s)
- Ilenia Paparella
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Islay Campbell
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Roya Sharifpour
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Elise Beckers
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
- Alzheimer Centre Limburg, School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, 6229 ET, Maastricht, The Netherlands
| | - Alexandre Berger
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
- Institute of Neuroscience (IoNS), Université Catholique de Louvain (UCLouvain), 1200, Brussels, Belgium
- Synergia Medical SA, 1435, Mont-Saint-Guibert, Belgium
| | | | - Ekaterina Koshmanova
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Nasrin Mortazavi
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Puneet Talwar
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Christian Degueldre
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Laurent Lamalle
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Siya Sherif
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Christophe Phillips
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
| | - Pierre Maquet
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium
- Neurology Department, CHU de Liège, 4000, Liège, Belgium
| | - Gilles Vandewalle
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, 4000, Liège, Belgium.
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11
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Tamayo E, Mouland JW, Lucas RJ, Brown TM. Regulation of mouse exploratory behaviour by irradiance and cone-opponent signals. BMC Biol 2023; 21:178. [PMID: 37605163 PMCID: PMC10441731 DOI: 10.1186/s12915-023-01663-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 07/14/2023] [Indexed: 08/23/2023] Open
Abstract
BACKGROUND Animal survival depends on the ability to adjust behaviour according to environmental conditions. The circadian system plays a key role in this capability, with diel changes in the quantity (irradiance) and spectral content ('colour') of ambient illumination providing signals of time-of-day that regulate the timing of rest and activity. Light also exerts much more immediate effects on behaviour, however, that are equally important in shaping daily activity patterns. Hence, nocturnal mammals will actively avoid light and dramatically reduce their activity when light cannot be avoided. The sensory mechanisms underlying these acute effects of light are incompletely understood, particularly the importance of colour. RESULTS To define sensory mechanisms controlling mouse behaviour, we used photoreceptor-isolating stimuli and mice with altered cone spectral sensitivity (Opn1mwR), lacking melanopsin (Opn1mwR; Opn4-/-) or cone phototransduction (Cnga3-/-) in assays of light-avoidance and activity suppression. In addition to roles for melanopsin-dependent irradiance signals, we find a major influence of spectral content in both cases. Hence, remarkably, selective increases in S-cone irradiance (producing a blue-shift in spectrum replicating twilight) drive light-seeking behaviour and promote activity. These effects are opposed by signals from longer-wavelength sensitive cones, indicating a true spectrally-opponent mechanism. Using c-Fos-mapping and multielectrode electrophysiology, we further show these effects are associated with a selective cone-opponent modulation of neural activity in the key brain site implicated in acute effects of light on behaviour, the subparaventricular zone. CONCLUSIONS Collectively, these data reveal a mechanism whereby blue-shifts in the spectrum of environmental illumination, such as during twilight, promote mouse exploratory behaviour.
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Affiliation(s)
- E Tamayo
- Centre for Biological Timing, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - J W Mouland
- Centre for Biological Timing, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - R J Lucas
- Centre for Biological Timing, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - T M Brown
- Centre for Biological Timing, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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12
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Quan Y, Duan H, Zhan Z, Shen Y, Lin R, Liu T, Zhang T, Wu J, Huang J, Zhai G, Song X, Zhou Y, Sun X. Binocular head-mounted chromatic pupillometry can detect structural and functional loss in glaucoma. Front Neurosci 2023; 17:1187619. [PMID: 37456990 PMCID: PMC10346847 DOI: 10.3389/fnins.2023.1187619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 06/07/2023] [Indexed: 07/18/2023] Open
Abstract
Aim The aim of this study is to evaluate the utility of binocular chromatic pupillometry in detecting impaired pupillary light response (PLR) in patients with primary open-angle glaucoma (POAG) and to assess the feasibility of using binocular chromatic pupillometer in opportunistic POAG diagnosis in community-based or telemedicine-based services. Methods In this prospective, cross-sectional study, 74 patients with POAG and 23 healthy controls were enrolled. All participants underwent comprehensive ophthalmologic examinations including optical coherence tomography (OCT) and standard automated perimetry (SAP). The PLR tests included sequential tests of full-field chromatic stimuli weighted by rods, intrinsically photosensitive retinal ganglion cells (ipRGCs), and cones (Experiment 1), as well as alternating chromatic light flash-induced relative afferent pupillary defect (RAPD) test (Experiment 2). In Experiment 1, the constricting amplitude, velocity, and time to maximum constriction/dilation were calculated in three cell type-weighted responses, and the post-illumination response of ipRGC-weighted response was evaluated. In Experiment 2, infrared pupillary asymmetry (IPA) amplitude and anisocoria duration induced by intermittent blue or red light flashes were calculated. Results In Experiment 1, the PLR of POAG patients was significantly reduced in all conditions, reflecting the defect in photoreception through rods, cones, and ipRGCs. The variable with the highest area under the receiver operating characteristic curve (AUC) was time to max dilation under ipRGC-weighted stimulus, followed by the constriction amplitude under cone-weighted stimulus and the constriction amplitude response to ipRGC-weighted stimuli. The impaired PLR features were associated with greater visual field loss, thinner retinal nerve fiber layer (RNFL) thickness, and cupping of the optic disk. In Experiment 2, IPA and anisocoria duration induced by intermittent blue or red light flashes were significantly greater in participants with POAG than in controls. IPA and anisocoria duration had good diagnostic value, correlating with the inter-eye asymmetry of visual field loss. Conclusion We demonstrate that binocular chromatic pupillometry could potentially serve as an objective clinical tool for opportunistic glaucoma diagnosis in community-based or telemedicine-based services. Binocular chromatic pupillometry allows an accurate, objective, and rapid assessment of retinal structural impairment and functional loss in glaucomatous eyes of different severity levels.
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Affiliation(s)
- Yadan Quan
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Huiyu Duan
- Institute of Image Communication and Network Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Zongyi Zhan
- Department of Retinal Disease, Shenzhen Eye Institute, Shenzhen Eye Hospital, Shenzhen Eye Hospital Affiliated to Jinan University, Shenzhen, China
| | - Yuening Shen
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
| | - Rui Lin
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Tingting Liu
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Ting Zhang
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Jihong Wu
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Jing Huang
- Institute of Image Communication and Network Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Guangtao Zhai
- Institute of Image Communication and Network Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Xuefei Song
- Department of Ophthalmology, Ninth People's Hospital of Shanghai, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yixiong Zhou
- Department of Ophthalmology, Ninth People's Hospital of Shanghai, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, China
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13
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Evidence of separate influence of moon and sun on light synchronization of mussel's daily rhythm during the polar night. iScience 2023; 26:106168. [PMID: 36876122 PMCID: PMC9978622 DOI: 10.1016/j.isci.2023.106168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/24/2022] [Accepted: 02/06/2023] [Indexed: 02/11/2023] Open
Abstract
Marine organisms living at high latitudes are faced with a light climate that undergoes drastic annual changes, especially during the polar night (PN) when the sun remains below the horizon for months. This raises the question of a possible synchronization and entrainment of biological rhythms under the governance of light at very low intensities. We analyzed the rhythms of the mussel Mytilus sp. during PN. We show that (1) mussels expressed a rhythmic behavior during PN; (2) a monthly moonlight rhythm was expressed; (3) a daily rhythm was expressed and influenced by both sunlight and moonlight; and (4) depending on the different times of PN and moon cycle characteristics, we were able to discriminate whether the moon or the sun synchronize the daily rhythm. Our findings fuel the idea that the capability of moonlight to synchronize daily rhythms when sunlight is not sufficient would be a crucial advantage during PN.
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14
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Wang Y, Belušič G, Pen I, Beukeboom LW, Wertheim B, Stavenga DG, Hut RA. Circadian rhythm entrainment of the jewel wasp, Nasonia vitripennis, by antagonistic interactions of multiple spectral inputs. Proc Biol Sci 2023; 290:20222319. [PMID: 36750184 PMCID: PMC9904953 DOI: 10.1098/rspb.2022.2319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Circadian light entrainment in some insects is regulated by blue-light-sensitive cryptochrome (CRY) protein that is expressed in the clock neurons, but this is not the case in hymenopterans. The hymenopteran clock does contain CRY, but it appears to be light-insensitive. Therefore, we investigated the role of retinal photoreceptors in the photic entrainment of the jewel wasp Nasonia vitripennis. Application of monochromatic light stimuli at different light intensities caused phase shifts in the wasp's circadian activity from which an action spectrum with three distinct peaks was derived. Electrophysiological recordings from the compound eyes and ocelli revealed the presence of three photoreceptor classes, with peak sensitivities at 340 nm (ultraviolet), 450 nm (blue) and 530 nm (green). An additional photoreceptor class in the ocelli with sensitivity maximum at 560-580 nm (red) was found. Whereas a simple sum of photoreceptor spectral sensitivities could not explain the action spectrum of the circadian phase shifts, modelling of the action spectrum indicates antagonistic interactions between pairs of spectral photoreceptors, residing in the compound eyes and the ocelli. Our findings imply that the photic entrainment mechanism in N. vitripennis encompasses the neural pathways for measuring the absolute luminance as well as the circuits mediating colour opponency.
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Affiliation(s)
- Yifan Wang
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712 CP Groningen, the Netherlands
| | - Gregor Belušič
- Department of Biology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Ido Pen
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712 CP Groningen, the Netherlands
| | - Leo W. Beukeboom
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712 CP Groningen, the Netherlands
| | - Bregje Wertheim
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712 CP Groningen, the Netherlands
| | - Doekele G. Stavenga
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712 CP Groningen, the Netherlands
| | - Roelof A. Hut
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9712 CP Groningen, the Netherlands
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15
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Tangled up in blue: Contribution of short-wavelength sensitive cones in human circadian photoentrainment. Proc Natl Acad Sci U S A 2023; 120:e2219617120. [PMID: 36598954 PMCID: PMC9926240 DOI: 10.1073/pnas.2219617120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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16
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Wang HB, Zhou D, Luk SHC, In Cha H, Mac A, Chae R, Matynia A, Harrison B, Afshari S, Block GD, Ghiani CA, Colwell CS. Long wavelength light reduces the negative consequences of dim light at night. Neurobiol Dis 2023; 176:105944. [PMID: 36493974 PMCID: PMC10594349 DOI: 10.1016/j.nbd.2022.105944] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 11/22/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Many patients with autism spectrum disorders (ASD) show disturbances in their sleep/wake cycles, and they may be particularly vulnerable to the impact of circadian disruptors. We have previously shown that a 2-weeks exposure to dim light at night (DLaN) disrupts diurnal rhythms, increases repetitive behaviors and reduces social interactions in contactin-associated protein-like 2 knock out (Cntnap2 KO) mice. The deleterious effects of DLaN may be mediated by intrinsically photosensitive retinal ganglion cells (ipRGCs) expressing the photopigment melanopsin, which is maximally sensitive to blue light (480 nm). In this study, the usage of a light-emitting diode array enabled us to shift the spectral properties of the DLaN while keeping the intensity of the illumination at 10 lx. First, we confirmed that the short-wavelength enriched lighting produced strong acute suppression of locomotor activity (masking), robust light-induced phase shifts, and cFos expression in the suprachiasmatic nucleus in wild-type (WT) mice, while the long-wavelength enriched lighting evoked much weaker responses. Opn4DTA mice, lacking the melanopsin expressing ipRGCs, were resistant to DLaN effects. Importantly, shifting the DLaN stimulus to longer wavelengths mitigated the negative impact on the activity rhythms and 'autistic' behaviors (i.e. reciprocal social interactions, repetitive grooming) in the Cntnap2 KO as well as in WT mice. The short-, but not the long-wavelength enriched, DLaN triggered cFos expression in in the basolateral amygdala (BLA) as well as in the peri-habenula region raising that possibility that these cell populations may mediate the effects. Broadly, our findings are consistent with the recommendation that spectral properties of light at night should be considered to optimize health in neurotypical as well as vulnerable populations.
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Affiliation(s)
- Huei-Bin Wang
- Molecular, Cellular, Integrative Physiology Graduate Program, David Geffen School of Medicine, University of California Los Angeles, USA; Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA
| | - David Zhou
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA
| | - Shu Hon Christopher Luk
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA
| | - Hye In Cha
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA
| | - Amanda Mac
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA
| | - Rim Chae
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA
| | - Anna Matynia
- Laboratory of Ocular Molecular and Cellular Biology and Genetics, Jules Stein Eye Institute, David Geffen School of Medicine, University of California Los Angeles, USA
| | | | | | - Gene D Block
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA
| | - Cristina A Ghiani
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA; Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, USA; Intellectual and Developmental Disabilities Center, David Geffen School of Medicine, University of California Los Angeles, USA
| | - Christopher S Colwell
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, USA; Intellectual and Developmental Disabilities Center, David Geffen School of Medicine, University of California Los Angeles, USA.
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17
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Dauchy RT, Blask DE. Vivarium Lighting as an Important Extrinsic Factor Influencing Animal-based Research. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2023; 62:3-25. [PMID: 36755210 PMCID: PMC9936857 DOI: 10.30802/aalas-jaalas-23-000003] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/26/2022] [Accepted: 09/02/2022] [Indexed: 01/22/2023]
Abstract
Light is an extrinsic factor that exerts widespread influence on the regulation of circadian, physiologic, hormonal, metabolic, and behavioral systems of all animals, including those used in research. These wide-ranging biologic effects of light are mediated by distinct photoreceptors, the melanopsin-containing intrinsically photosensitive retinal ganglion cells of the nonvisual system, which interact with the rods and cones of the conventional visual system. Here, we review the nature of light and circadian rhythms, current industry practices and standards, and our present understanding of the neurophysiology of the visual and nonvisual systems. We also consider the implications of this extrinsic factor for vivarium measurement, production, and technological application of light, and provide simple recommendations on artificial lighting for use by regulatory authorities, lighting manufacturers, designers, engineers, researchers, and research animal care staff that ensure best practices for optimizing animal health and wellbeing and, ultimately, improving scientific outcomes.
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Key Words
- blad, blue-enriched led light at daytime
- clock, circadian locomotor output kaput
- cct, correlated color temperature
- cwf, cool white fluorescent
- iprgc, intrinsically photosensitive retinal ganglion cell
- hiomt, hydroxyindole-o-methyltransferase
- lan, light at night
- led, light-emitting diode
- plr, pupillary light reflex
- scn, suprachiasmatic nuclei
- spd, spectral power distribution
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Affiliation(s)
- Robert T Dauchy
- Department of Structural and Cellular Biology, Laboratory of Chrono-Neuroendocrine Oncology, Tulane University School of Medicine, New Orleans, Louisiana
| | - David E Blask
- Department of Structural and Cellular Biology, Laboratory of Chrono-Neuroendocrine Oncology, Tulane University School of Medicine, New Orleans, Louisiana
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18
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Lan YQ, Yu MB, Zhan ZY, Huang YR, Zhao LW, Quan YD, Li ZJ, Sun DF, Wu YL, Wu HY, Liu ZT, Wu KL. Use of a tissue clearing technique combined with retrograde trans-synaptic viral tracing to evaluate changes in mouse retinorecipient brain regions following optic nerve crush. Neural Regen Res 2023; 18:913-921. [DOI: 10.4103/1673-5374.353852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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19
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Uprety S, Adhikari P, Feigl B, Zele AJ. Melanopsin photoreception differentially modulates rod-mediated and cone-mediated human temporal vision. iScience 2022; 25:104529. [PMID: 35754721 PMCID: PMC9218364 DOI: 10.1016/j.isci.2022.104529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/04/2022] [Accepted: 05/30/2022] [Indexed: 11/17/2022] Open
Abstract
To evaluate the nature of interactions between visual pathways transmitting the slower melanopsin and faster rod and cone signals, we implement a temporal phase summation paradigm in human observers using photoreceptor-directed stimuli. We show that melanopsin stimulation interacts with and alters both rod-mediated and cone-mediated vision regardless of whether it is perceptually visible or not. Melanopsin-rod interactions result in either inhibitory or facilitatory summation depending on the temporal frequency and photoreceptor pathway contrast sensitivity. Moreover, by isolating rod vision, we reveal a bipartite intensity response property of the rod pathway in photopic lighting that extends its operational range at lower frequencies to beyond its classic saturation limits but at the expense of attenuating sensitivity at higher frequencies. In comparison, melanopsin-cone interactions always lead to facilitation. These interactions can be described by linear or probability summations and potentially involve multiple intraretinal and visual cortical pathways to set human visual contrast sensitivity. Melanopsin ipRGCs support vision independent of the rod and cone signals Rod pathways mediate robust visual responses in daylight Temporal contrast sensitivity is contingent on the melanopsin excitation level Visual performance is collectively regulated by melanopsin, rod and cone pathways
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Affiliation(s)
- Samir Uprety
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia
| | - Prakash Adhikari
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia
| | - Beatrix Feigl
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,Queensland Eye Institute, Brisbane, QLD 4101, Australia
| | - Andrew J Zele
- Centre for Vision and Eye Research, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD 4059, Australia
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20
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Allen AA, Pierce AT, Dauchy RT, Voros GB, Dobek GL. Influence of Light Phase Exposure to LED Lighting on Circadian Levels of Neuroendocrine Hormones in Sprague-Dawley Rats. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2022; 61:333-343. [PMID: 35738839 PMCID: PMC9674009 DOI: 10.30802/aalas-jaalas-21-000123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/13/2022] [Accepted: 05/02/2022] [Indexed: 01/03/2023]
Abstract
Light and lighting protocols of animal research facilities are critically important to the outcomes of biomedical research that uses animals. Previous studies from our laboratory showed that the wavelength (color) of light in animal housing areas affects the nocturnal melatonin signal that temporally coordinates circadian rhythms in rodents. Here, we tested the hypothesis that exposure to LED light enriched in the blue-appearing portion (460-480 nm) of the visible spectrum during the light phase (bLAD) influences circadian concentrations of select neuroendocrine hormones in adolescent Sprague-Dawley rats. Male and female rats (4 to 5 wk old) were housed on a novel IVC system under a 12L:12D in either cool-white fluorescent (control, n = 72) or bLAD (experimental, n = 72) lighting. Every third day, body weight and food and water consumption were measured. On Day 30, rats were anesthetized with ketamine/xylazine and terminal collection of arterial blood was performed to quantify serum concentrations of melatonin, corticosterone, insulin, and glucose at 6 circadian time points (0400, 0800, 1200, 1600, 2000, 2400). As compared with male and female rats housed under cool white fluorescent (CWF) lighting, rats in bLAD lighting showed a 6-fold higher peak in dark phase serum melatonin (P < 0.05). Effects on serum corticosterone were sex dependent, as CWF and bLAD females had significantly higher corticosterone levels than did CWF and bLAD males, respectively. CWF and bLAD females had significantly higher serum glucose overall as compared with males. However, serum insulin was not affected by sex (M or F) or lighting conditions (CWF or bLAD). These data show that housing Sprague-Dawley rats under bLAD lighting conditions increases circadian peaks of melatonin without increasing serum levels of corticosterone, glucose or insulin, indicating less variation of circadian cycling of key neuroendocrine hormones in bLAD-exposed rats.
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Key Words
- blad, blue-enriched light-emitting diode light-at-day
- cwf, cool white fluorescent
- hpa, hypothalamic-pituitary-adrenal
- ip, intraperitoneal
- iprgc, intrinsically photosensitive retinal ganglion cell
- ivc, individual ventilated caging
- led, light-emitting diode
- lx, lux
- rht, retinohypothalamic tract
- scn, suprachiasmic nucleus
- spd, spectral power distribution
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Affiliation(s)
- Alexis A Allen
- Comparative Medicine, Tulane University, New Orleans, LA, United States;,
| | - Amy T Pierce
- Comparative Medicine, Tulane University, New Orleans, LA, United States
| | - Robert T Dauchy
- Structural & Cellular Biology, Tulane University, New Orleans, LA, United States
| | - George B Voros
- Comparative Medicine, Tulane University, New Orleans, LA, United States
| | - Georgina L Dobek
- Comparative Medicine, Tulane University, New Orleans, LA, United States
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Divergent outer retinal circuits drive image and non-image visual behaviors. Cell Rep 2022; 39:111003. [PMID: 35767957 PMCID: PMC9400924 DOI: 10.1016/j.celrep.2022.111003] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/25/2022] [Accepted: 06/03/2022] [Indexed: 11/22/2022] Open
Abstract
Image- and non-image-forming vision are essential for animal behavior. Here we use genetically modified mouse lines to examine retinal circuits driving image- and non-image-functions. We describe the outer retinal circuits underlying the pupillary light response (PLR) and circadian photoentrainment, two non-image-forming behaviors. Rods and cones signal light increments and decrements through the ON and OFF pathways, respectively. We find that the OFF pathway drives image-forming vision but cannot drive circadian photoentrainment or the PLR. Cone light responses drive image formation but fail to drive the PLR. At photopic levels, rods use the primary and secondary rod pathways to drive the PLR, whereas at the scotopic and mesopic levels, rods use the primary pathway to drive the PLR, and the secondary pathway is insufficient. Circuit dynamics allow rod ON pathways to drive two non-image-forming behaviors across a wide range of light intensities, whereas the OFF pathway is potentially restricted to image formation.
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22
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Lee C, Liang F, Lee I, Lu T, Shan Y, Jeng C, Zou Y, Yu H, Chen (Alen) S. External light‐dark cycle shapes gut microbiota through intrinsically photosensitive retinal ganglion cells. EMBO Rep 2022; 23:e52316. [PMID: 35476894 PMCID: PMC9171413 DOI: 10.15252/embr.202052316] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 12/24/2021] [Accepted: 03/18/2022] [Indexed: 01/15/2023] Open
Abstract
Gut microbiota are involved in many physiological functions such as metabolism, brain development, and neurodegenerative diseases. Many microbes in the digestive tract do not maintain a constant level of their relative abundance but show daily oscillations under normal conditions. Recent evidence indicates that chronic jetlag, constant darkness, or deletion of the circadian core gene can alter the composition of gut microbiota and dampen the daily oscillation of gut microbes. However, the neuronal circuit responsible for modulating gut microbiota remained unclear. Using genetic mouse models and 16s rRNA metagenomic analysis, we find that light-dark cycle information transmitted by the intrinsically photosensitive retinal ganglion cells (ipRGCs) is essential for daily oscillations of gut microbes under temporal restricted high-fat diet conditions. Furthermore, aberrant light exposure such as dim light at night (dLAN) can alter the composition, relative abundance, and daily oscillations of gut microbiota. Together, our results indicate that external light-dark cycle information can modulate gut microbiota in the direction from the brain to the gut via the sensory system.
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Affiliation(s)
- Chi‐Chan Lee
- Department of Life Science National Taiwan University Taipei Taiwan
| | - Feng Liang
- Department of Life Science National Taiwan University Taipei Taiwan
| | - I‐Chi Lee
- Department of Life Science National Taiwan University Taipei Taiwan
| | - Tsung‐Hao Lu
- Department of Life Science National Taiwan University Taipei Taiwan
| | - Yu‐Yau Shan
- Department of Life Science National Taiwan University Taipei Taiwan
| | - Chih‐Fan Jeng
- Department of Life Science National Taiwan University Taipei Taiwan
| | - Yan‐Fang Zou
- Department of Life Science National Taiwan University Taipei Taiwan
| | - Hon‐Tsen Yu
- Department of Life Science National Taiwan University Taipei Taiwan
- Genome and Systems Biology Degree Program National Taiwan University and Academia Sinica Taipei Taiwan
| | - Shih‐Kuo Chen (Alen)
- Department of Life Science National Taiwan University Taipei Taiwan
- Genome and Systems Biology Degree Program National Taiwan University and Academia Sinica Taipei Taiwan
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Two light sensors decode moonlight versus sunlight to adjust a plastic circadian/circalunidian clock to moon phase. Proc Natl Acad Sci U S A 2022; 119:e2115725119. [PMID: 35622889 PMCID: PMC9295771 DOI: 10.1073/pnas.2115725119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The moon provides highly reliable time information to organisms. Whereas sunlight is known to set daily animal timing systems, mechanistic insight into the impact of moonlight on such systems remains scarce. We establish that the marine bristleworm Platynereis dumerilii times the precise hours of mass spawning by integrating lunar light information into a plastic daily timing system able to run with circadian (∼24 h) or circalunidian (∼24.8 h) periodicity. The correct interpretation of moonlight is mediated by the interplay of two light sensors: a cryptochrome and a melanopsin ortholog provide information on light valence and moonrise time, respectively. Besides its ecological relevance, our work provides a plausible explanation for long-standing observations of light intensity–dependent differences in circadian clock periods. Many species synchronize their physiology and behavior to specific hours. It is commonly assumed that sunlight acts as the main entrainment signal for ∼24-h clocks. However, the moon provides similarly regular time information. Consistently, a growing number of studies have reported correlations between diel behavior and lunidian cycles. Yet, mechanistic insight into the possible influences of the moon on ∼24-h timers remains scarce. We have explored the marine bristleworm Platynereis dumerilii to investigate the role of moonlight in the timing of daily behavior. We uncover that moonlight, besides its role in monthly timing, also schedules the exact hour of nocturnal swarming onset to the nights’ darkest times. Our work reveals that extended moonlight impacts on a plastic clock that exhibits <24 h (moonlit) or >24 h (no moon) periodicity. Abundance, light sensitivity, and genetic requirement indicate that the Platynereis light receptor molecule r-Opsin1 serves as a receptor that senses moonrise, whereas the cryptochrome protein L-Cry is required to discriminate the proper valence of nocturnal light as either moonlight or sunlight. Comparative experiments in Drosophila suggest that cryptochrome’s principle requirement for light valence interpretation is conserved. Its exact biochemical properties differ, however, between species with dissimilar timing ecology. Our work advances the molecular understanding of lunar impact on fundamental rhythmic processes, including those of marine mass spawners endangered by anthropogenic change.
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Abstract
SignificanceThe function of our biological clock is dependent on environmental light. Rodent studies have shown that there are multiple colors that affect the clock, but indirect measures in humans suggest blue light is key. We performed functional MRI studies in human subjects with unprecedented spatial resolution to investigate color sensitivity of our clock. Here, we show that narrowband blue, green, and orange light were all effective in changing neuronal activity of the clock. While the clock of nocturnal rodents is excited by light, the human clock responds with a decrease in neuronal activity as indicated by a negative BOLD response. The sensitivity of the clock to multiple colors should be integrated in light therapy aimed to strengthen our 24-h rhythms.
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25
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Joyce DS, Spitschan M, Zeitzer JM. Duration invariance and intensity dependence of the human circadian system phase shifting response to brief light flashes. Proc Biol Sci 2022; 289:20211943. [PMID: 35259981 PMCID: PMC8905166 DOI: 10.1098/rspb.2021.1943] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 02/14/2022] [Indexed: 01/09/2023] Open
Abstract
The melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) are characterized by a delayed off-time following the cessation of light stimulation. Here, we exploited this unusual physiologic property to characterize the exquisite sensitivity of the human circadian system to flashed light. In a 34 h in-laboratory between-subjects design, we examined phase shifting in response to variable-intensity (3-9500 photopic lux) flashes at fixed duration (2 ms; n = 28 participants) and variable-duration (10 µs-10 s) flashes at fixed intensity (2000 photopic lux; n = 31 participants). Acute melatonin suppression, objective alertness and subjective sleepiness during the flash sequence were also assessed. We find a dose-response relationship between flash intensity and circadian phase shift, with an indication of a possible threshold-like behaviour. We find a slight parametric relationship between flash duration and circadian phase shift. Consistent with prior studies, we observe no dose-response relationship to either flash intensity or duration and the acute impact of light on melatonin suppression, objective alertness or subjective sleepiness. Our findings are consistent with circadian responses to a sequence of flashes being mediated by rod or cone photoreceptors via ipRGC integration.
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Affiliation(s)
- Daniel S. Joyce
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Mental Illness Research Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA, USA
- Department of Psychology, University of Nevada Reno, Reno, NV, USA
| | - Manuel Spitschan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Translational Sensory and Circadian Neuroscience, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
- TUM Department of Sport and Health Sciences (TUM SG), Technical University of Munich, Munich, Germany
| | - Jamie M. Zeitzer
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Mental Illness Research Education and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA, USA
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26
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van der Sande E, Haarman AEG, Quint WH, Tadema KCD, Meester-Smoor MA, Kamermans M, De Zeeuw CI, Klaver CCW, Winkelman BHJ, Iglesias AI. The Role of GJD2(Cx36) in Refractive Error Development. Invest Ophthalmol Vis Sci 2022; 63:5. [PMID: 35262731 PMCID: PMC8934558 DOI: 10.1167/iovs.63.3.5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 02/16/2022] [Indexed: 02/06/2023] Open
Abstract
Refractive errors are common eye disorders characterized by a mismatch between the focal power of the eye and its axial length. An increased axial length is a common cause of the refractive error myopia (nearsightedness). The substantial increase in myopia prevalence over the last decades has raised public health concerns because myopia can lead to severe ocular complications later in life. Genomewide association studies (GWAS) have made considerable contributions to the understanding of the genetic architecture of refractive errors. Among the hundreds of genetic variants identified, common variants near the gap junction delta-2 (GJD2) gene have consistently been reported as one of the top hits. GJD2 encodes the connexin 36 (Cx36) protein, which forms gap junction channels and is highly expressed in the neural retina. In this review, we provide current evidence that links GJD2(Cx36) to the development of myopia. We summarize the gap junctional communication in the eye and the specific role of GJD2(Cx36) in retinal processing of visual signals. Finally, we discuss the pathways involving dopamine and gap junction phosphorylation and coupling as potential mechanisms that may explain the role of GJD2(Cx36) in refractive error development.
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Affiliation(s)
- Emilie van der Sande
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- Netherlands Institute for Neuroscience (NIN), Royal Dutch Academy of Art & Science (KNAW), Amsterdam, The Netherlands
| | - Annechien E. G. Haarman
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Wim H. Quint
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Kirke C. D. Tadema
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Magda A. Meester-Smoor
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Maarten Kamermans
- Netherlands Institute for Neuroscience (NIN), Royal Dutch Academy of Art & Science (KNAW), Amsterdam, The Netherlands
- Department of Biomedical Physics and Biomedical Photonics, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Chris I. De Zeeuw
- Netherlands Institute for Neuroscience (NIN), Royal Dutch Academy of Art & Science (KNAW), Amsterdam, The Netherlands
- Department of Neuroscience, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Caroline C. W. Klaver
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Beerend H. J. Winkelman
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- Netherlands Institute for Neuroscience (NIN), Royal Dutch Academy of Art & Science (KNAW), Amsterdam, The Netherlands
- Department of Neuroscience, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Adriana I. Iglesias
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
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27
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Ashton A, Foster RG, Jagannath A. Photic Entrainment of the Circadian System. Int J Mol Sci 2022; 23:ijms23020729. [PMID: 35054913 PMCID: PMC8775994 DOI: 10.3390/ijms23020729] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/17/2021] [Accepted: 12/22/2021] [Indexed: 01/27/2023] Open
Abstract
Circadian rhythms are essential for the survival of all organisms, enabling them to predict daily changes in the environment and time their behaviour appropriately. The molecular basis of such rhythms is the circadian clock, a self-sustaining molecular oscillator comprising a transcriptional–translational feedback loop. This must be continually readjusted to remain in alignment with the external world through a process termed entrainment, in which the phase of the master circadian clock in the suprachiasmatic nuclei (SCN) is adjusted in response to external time cues. In mammals, the primary time cue, or “zeitgeber”, is light, which inputs directly to the SCN where it is integrated with additional non-photic zeitgebers. The molecular mechanisms underlying photic entrainment are complex, comprising a number of regulatory factors. This review will outline the photoreception pathways mediating photic entrainment, and our current understanding of the molecular pathways that drive it in the SCN.
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28
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Mason BJ, Tubbs AS, Fernandez FX, Grandner MA. Spectrophotometric properties of commercially available blue blockers across multiple lighting conditions. Chronobiol Int 2022; 39:653-664. [PMID: 34983271 PMCID: PMC9106867 DOI: 10.1080/07420528.2021.2021229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Lenses that filter short-wavelength ("blue") light are commercially marketed to improve sleep and circadian health. Despite their widespread use, minimal data are available regarding their comparative efficacy in curtailing blue light exposure while maintaining visibility. Fifty commercial lenses were evaluated using five light sources: a blue LED array, a computer tablet display, an incandescent lamp, a fluorescent overhead luminaire, and sunlight. Absolute irradiance was measured at baseline and for each lens across the visual spectrum (380-780 nm), which allowed calculation of percent transmission. Transmission specificity was also calculated to determine whether light transmission was predominantly circadian-proficient (455-560 nm) or non-proficient (380-454 nm and 561-780 nm). Lenses were grouped by tint and metrics were compared between groups. Red-tinted lenses exhibited the lowest transmission of circadian-proficient light, while reflective blue lenses had the highest transmission. Orange-tinted lenses transmitted similar circadian-proficient light as red-tinted lenses but transmitted more non-circadian-proficient light, resulting in higher transmission specificity. Orange-tinted lenses had the highest transmission specificity while limiting biologically active light exposure in ordinary lighting conditions. Glasses incorporating these lenses currently have the greatest potential to support circadian sleep-wake rhythms.
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Affiliation(s)
- Brooke J Mason
- Sleep and Health Research Program, Department of Psychiatry, University of Arizona College of Medicine - Tucson, Tucson, Arizona, USA
| | - Andrew S Tubbs
- Sleep and Health Research Program, Department of Psychiatry, University of Arizona College of Medicine - Tucson, Tucson, Arizona, USA
| | - Fabian-Xosé Fernandez
- Light Algorithms Laboratory, Department of Psychology, University of Arizona College of Science, Tucson, Arizona, USA
| | - Michael A Grandner
- Sleep and Health Research Program, Department of Psychiatry, University of Arizona College of Medicine - Tucson, Tucson, Arizona, USA
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29
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Beyond irradiance: Visual signals influencing mammalian circadian function. PROGRESS IN BRAIN RESEARCH 2022; 273:145-169. [DOI: 10.1016/bs.pbr.2022.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Walker WH, Kaper AL, Meléndez-Fernández OH, Bumgarner JR, Liu JA, Walton JC, DeVries AC, Nelson RJ. Time-restricted feeding alters the efficiency of mammary tumor growth. Chronobiol Int 2021; 39:535-546. [PMID: 34894935 DOI: 10.1080/07420528.2021.2011306] [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] [Indexed: 10/19/2022]
Abstract
Disruption of circadian rhythms has detrimental host consequences. Indeed, both clinical and foundational science demonstrate a clear relationship between disruption of circadian rhythms and cancer initiation and progression. Because timing of food intake can act as a zeitgeber (i.e., entrainment signal) for the circadian clock, and most individuals in the developed world have access to food at all times of the day in a "24/7" society, we sought to determine the effects of timing of food intake on mammary tumor growth. We hypothesized that restricting access to food to during the inactive phase would accelerate tumor growth. Adult female Balb/C mice received a unilateral orthotopic injection of murine mammary carcinoma 4T1 cells into the ninth inguinal mammary gland. Beginning on the day of tumor injection and continuing until the end of the experiment, mice were food restricted to their active phase (ZT12 (lights off)- ZT0 (lights on), inactive phase (ZT0 - ZT12), or had ad libitum access to food. Mice that were food restricted to their inactive phase displayed a significant increase in body mass on days 7 and 14 of tumor growth relative to active phase or ad libitum fed mice. Additionally, mice fed during their inactive phase demonstrated a 20% reduction in food consumption relative to mice fed during their active phase and a 17% reduction in food consumption relative to ab libitum fed mice. Tumor volume was not significantly different between groups. However, food restricting mice to their inactive phase increased mammary tumor growth efficiency (i.e., mg of tumor mass per gram of food intake) relative to mice fed during the active phase and approached significance (p = .06) relative to ad libitum fed mice. To determine a potential explanation for the increased tumor growth efficiency, we examined rhythms of activity and body temperature. Mice fed during the inactive phase displayed significantly disrupted daily activity and body temperature rhythms relative to both other feeding regimens. Together, these data demonstrate that improperly timed food intake can have detrimental consequences on mammary tumor growth likely via disrupted circadian rhythms.
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Affiliation(s)
- William H Walker
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia, USA
| | - Alexis L Kaper
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia, USA
| | | | - Jacob R Bumgarner
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia, USA
| | - Jennifer A Liu
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia, USA
| | - James C Walton
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia, USA
| | - A Courtney DeVries
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia, USA.,Department of Medicine, Division of Oncology/Hematology, West Virginia, USA.,WVU Cancer Institute, West Virginia University, Morgantown, West Virginia, USA
| | - Randy J Nelson
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia, USA
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31
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Spectral sensitivity of circadian phase resetting, melatonin suppression and acute alerting effects of intermittent light exposure. Biochem Pharmacol 2021; 191:114504. [DOI: 10.1016/j.bcp.2021.114504] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 12/19/2022]
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32
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Physiological rhythms are influenced by photophase wavelength in a nocturnal and a diurnal rodent species from South Africa. Physiol Behav 2021; 240:113551. [PMID: 34375624 DOI: 10.1016/j.physbeh.2021.113551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/02/2021] [Accepted: 08/04/2021] [Indexed: 11/22/2022]
Abstract
The quality and quantity of light changes significantly over the course of the day. The effect of light intensity on physiological and behavioural responses of animals has been well documented, particularly during the scotophase, but the effect of the wavelength of light, particularly during the photophase, less so. We assessed the daily responses in urine production, urinary 6-sulfatoxymelatonin (6-SMT) and glucocorticoid metabolite (uGCM) concentrations in the nocturnal Namaqua rock mouse (Micaelamys namaquensis) and diurnal four striped field mouse (Rhabdomys pumilio) under varying wavelengths of near monochromatic photophase (daytime) lighting. Animals were exposed to a short-wavelength light cycle (SWLC; ∼465-470 nm), a medium-wavelength light cycle (MWLC; ∼515-520 nm) and a long-wavelength light cycle (LWLC; ∼625-630 nm). The SWLC significantly attenuated mean daily urine production rates and the mean daily levels of urinary 6-SMT and of uGCM were inversely correlated with wavelength in both species. The presence of the SWLC greatly augmented overall daily 6-SMT levels, and simultaneously led to the highest uGCM concentrations in both species. In M. namaquensis, the urine production rate and urinary 6-SMT concentrations were significantly higher during the scotophase compared to the photophase under the SWLC and MWLC, whereas the uGCM concentrations were significantly higher during the scotophase under all WLCs. In R. pumilio, the urine production rate and uGCM were significantly higher during the scotophase of the SWLC, not the MWLC and LWLC. Our results illustrate that wavelength in the photophase plays a central role in the entrainment of rhythms in diurnal and nocturnal African rodent species.
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33
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Distinct contribution of cone photoreceptor subtypes to the mammalian biological clock. Proc Natl Acad Sci U S A 2021; 118:2024500118. [PMID: 34050024 PMCID: PMC8179201 DOI: 10.1073/pnas.2024500118] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Synchronization of our biological clocks to the environmental day–night cycle critically depends on daily exposure to light. Here, we show that cones transmit distinct photic information to the clock by performing recordings of clock neurons in freely moving mice with cones as their only photoreceptors. This is in contrast to the expectation that exclusively melanopsin and rods fulfil this role. Moreover, we show that especially short-wavelength–sensitive cones as compared to mid-wavelength–sensitive cones are important. The evidence for a role for cones implicates that clocks respond to a broad spectrum of colors rather than to blue light, which can be used to strengthen the clock in humans. Ambient light detection is important for the synchronization of the circadian clock to the external solar cycle. Light signals are sent to the suprachiasmatic nuclei (SCN), the site of the major circadian pacemaker. It has been assumed that cone photoreceptors contribute minimally to synchronization. Here, however, we find that cone photoreceptors are sufficient for mediating entrainment and transmitting photic information to the SCN, as evaluated in mice that have only cones as functional photoreceptors. Using in vivo electrophysiological recordings in the SCN of freely moving cone-only mice, we observed light responses in SCN neuronal activity in response to 60-s pulses of both ultraviolet (UV) (λmax 365 nm) and green (λmax 505 nm) light. Higher irradiances of UV light led to irradiance-dependent enhancements in SCN neuronal activity, whereas higher irradiances of green light led to a reduction in the sustained response with only the transient response remaining. Responses in SCN neuronal activity decayed with a half-max time of ∼9 min for UV light and less than a minute for green light, indicating differential input between short-wavelength–sensitive and mid-wavelength–sensitive cones for the SCN responsiveness. Furthermore, we show that UV light is more effective for photoentrainment than green light. Based on the lack of a full sustained response in cone-only mice, we confirmed that rapidly alternating light levels, rather than slowly alternating light, caused substantial phase shifts. Together, our data provide strong evidence that cone types contribute to photoentrainment and differentially affect the electrical activity levels of the SCN.
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34
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Mouland JW, Martial FP, Lucas RJ, Brown TM. Modulations in irradiance directed at melanopsin, but not cone photoreceptors, reliably alter electrophysiological activity in the suprachiasmatic nucleus and circadian behaviour in mice. J Pineal Res 2021; 70:e12735. [PMID: 33793975 DOI: 10.1111/jpi.12735] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 03/23/2021] [Indexed: 12/25/2022]
Abstract
Intrinsically photosensitive retinal ganglion cells convey intrinsic, melanopsin-based, photoreceptive signals alongside those produced by rods and cones to the suprachiasmatic nucleus (SCN) circadian clock. To date, experimental data suggest that melanopsin plays a more significant role in measuring ambient light intensity than cone photoreception. Such studies have overwhelmingly used diffuse light stimuli, whereas light intensity in the world around us varies across space and time. Here, we investigated the extent to which melanopsin or cone signals support circadian irradiance measurements in the presence of naturalistic spatiotemporal variations in light intensity. To address this, we first presented high- and low-contrast movies to anaesthetised mice whilst recording extracellular electrophysiological activity from the SCN. Using a mouse line with altered cone sensitivity (Opn1mwR mice) and multispectral light sources we then selectively varied irradiance of the movies for specific photoreceptor classes. We found that steps in melanopic irradiance largely account for the light induced-changes in SCN activity over a range of starting light intensities and in the presence of spatiotemporal modulation. By contrast, cone-directed changes in irradiance only influenced SCN activity when spatiotemporal contrast was low. Consistent with these findings, under housing conditions where we could independently adjust irradiance for melanopsin versus cones, the period lengthening effects of constant light on circadian rhythms in behaviour were reliably determined by melanopic irradiance, regardless of irradiance for cones. These data add to the growing evidence that modulating effective irradiance for melanopsin is an effective strategy for controlling the circadian impact of light.
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Affiliation(s)
- Josh W Mouland
- Centre for Biological Timing, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
- Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
| | - Franck P Martial
- Centre for Biological Timing, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
- Division of Neuroscience and Experimental Psychology, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
| | - Robert J Lucas
- Centre for Biological Timing, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
- Division of Neuroscience and Experimental Psychology, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
| | - Timothy M Brown
- Centre for Biological Timing, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
- Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology Medicine and Health, University of Manchester, Manchester, UK
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35
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Functional modulation of phosphodiesterase-6 by calcium in mouse rod photoreceptors. Sci Rep 2021; 11:8938. [PMID: 33903621 PMCID: PMC8076185 DOI: 10.1038/s41598-021-88140-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/07/2021] [Indexed: 02/02/2023] Open
Abstract
Phosphodiesterase-6 (PDE6) is a key protein in the G-protein cascade converting photon information to bioelectrical signals in vertebrate photoreceptor cells. Here, we demonstrate that PDE6 is regulated by calcium, contrary to the common view that PDE1 is the unique PDE class whose activity is modulated by intracellular Ca2+. To broaden the operating range of photoreceptors, mammalian rod photoresponse recovery is accelerated mainly by two calcium sensor proteins: recoverin, modulating the lifetime of activated rhodopsin, and guanylate cyclase-activating proteins (GCAPs), regulating the cGMP synthesis. We found that decreasing rod intracellular Ca2+ concentration accelerates the flash response recovery and increases the basal PDE6 activity (βdark) maximally by ~ 30% when recording local electroretinography across the rod outer segment layer from GCAPs-/- recoverin-/- mice. Our modeling shows that a similar elevation in βdark can fully explain the observed acceleration of flash response recovery in low Ca2+. Additionally, a reduction of the free Ca2+ in GCAPs-/- recoverin-/- rods shifted the inhibition constants of competitive PDE inhibitor 3-isobutyl-1-methylxanthine (IBMX) against the thermally activated and light-activated forms of PDE6 to opposite directions, indicating a complex interaction between IBMX, PDE6, and calcium. The discovered regulation of PDE6 is a previously unknown mechanism in the Ca2+-mediated modulation of rod light sensitivity.
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36
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Ostrin LA. Ocular and systemic melatonin and the influence of light exposure. Clin Exp Optom 2021; 102:99-108. [DOI: 10.1111/cxo.12824] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 07/09/2018] [Accepted: 07/09/2018] [Indexed: 12/15/2022] Open
Affiliation(s)
- Lisa A Ostrin
- University of Houston College of Optometry, Houston, Texas, USA,
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37
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Wong KY, Fernandez FX. Circadian Responses to Light-Flash Exposure: Conceptualization and New Data Guiding Future Directions. Front Neurol 2021; 12:627550. [PMID: 33643205 PMCID: PMC7905211 DOI: 10.3389/fneur.2021.627550] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 01/21/2021] [Indexed: 01/03/2023] Open
Abstract
A growing number of studies document circadian phase-shifting after exposure to millisecond light flashes. When strung together by intervening periods of darkness, these stimuli evoke pacemaker responses rivaling or outmatching those created by steady luminance, suggesting that the circadian system's relationship to light can be contextualized outside the principle of simple dose-dependence. In the current review, we present a brief chronology of this work. We then develop a conceptual model around it that attempts to relate the circadian effects of flashes to a natural integrative process the pacemaker uses to intermittently sample the photic information available at dawn and dusk. Presumably, these snapshots are employed as building blocks in the construction of a coherent representation of twilight the pacemaker consults to orient the next day's physiology (in that way, flash-resetting of pacemaker rhythms might be less an example of a circadian visual illusion and more an example of the kinds of gestalt inferences that the image-forming system routinely makes when identifying objects within the visual field; i.e., closure). We conclude our review with a discussion on the role of cones in the pacemaker's twilight predictions, providing new electrophysiological data suggesting that classical photoreceptors—but not melanopsin—are necessary for millisecond, intermediate-intensity flash responses in ipRGCs (intrinsically photosensitive retinal ganglion cells). Future investigations are necessary to confirm this “Cone Sentinel Model” of circadian flash-integration and twilight-prediction, and to further define the contribution of cones vs. rods in transducing pacemaker flash signals.
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Affiliation(s)
- Kwoon Y Wong
- Department of Molecular, Cellular, & Developmental Biology, University of Michigan, Ann Arbor, MI, United States.,Department of Ophthalmology & Visual Sciences, University of Michigan, Ann Arbor, MI, United States
| | - Fabian-Xosé Fernandez
- Department of Psychology, BIO5 Research Institute, University of Arizona, Tucson, AZ, United States.,Department of Neurology, McKnight Brain Research Institute, University of Arizona, Tucson, AZ, United States
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38
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Rea MS, Nagare R, Figueiro MG. Modeling Circadian Phototransduction: Retinal Neurophysiology and Neuroanatomy. Front Neurosci 2021; 14:615305. [PMID: 33613175 PMCID: PMC7892603 DOI: 10.3389/fnins.2020.615305] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 12/28/2020] [Indexed: 12/11/2022] Open
Abstract
The retina is a complex, but well-organized neural structure that converts optical radiation into neural signals that convey photic information to a wide variety of brain structures. The present paper is concerned with the neural circuits underlying phototransduction for the central pacemaker of the human circadian system. The proposed neural framework adheres to orthodox retinal neuroanatomy and neurophysiology. Several postulated mechanisms are also offered to account for the high threshold and for the subadditive response to polychromatic light exhibited by the human circadian phototransduction circuit. A companion paper, modeling circadian phototransduction: Quantitative predictions of psychophysical data, provides a computational model for predicting psychophysical data associated with nocturnal melatonin suppression while staying within the constraints of the neurophysiology and neuroanatomy offered here.
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Affiliation(s)
- Mark S. Rea
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, United States
- Icahn School of Medicine, Mount Sinai, New York, NY, United States
| | - Rohan Nagare
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, United States
- Icahn School of Medicine, Mount Sinai, New York, NY, United States
| | - Mariana G. Figueiro
- Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, United States
- Icahn School of Medicine, Mount Sinai, New York, NY, United States
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Aranda ML, Schmidt TM. Diversity of intrinsically photosensitive retinal ganglion cells: circuits and functions. Cell Mol Life Sci 2021; 78:889-907. [PMID: 32965515 PMCID: PMC8650628 DOI: 10.1007/s00018-020-03641-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 08/10/2020] [Accepted: 09/03/2020] [Indexed: 12/25/2022]
Abstract
The melanopsin-expressing, intrinsically photosensitive retinal ganglion cells (ipRGCs) are a relatively recently discovered class of atypical ganglion cell photoreceptor. These ipRGCs are a morphologically and physiologically heterogeneous population that project widely throughout the brain and mediate a wide array of visual functions ranging from photoentrainment of our circadian rhythms, to driving the pupillary light reflex to improve visual function, to modulating our mood, alertness, learning, sleep/wakefulness, regulation of body temperature, and even our visual perception. The presence of melanopsin as a unique molecular signature of ipRGCs has allowed for the development of a vast array of molecular and genetic tools to study ipRGC circuits. Given the emerging complexity of this system, this review will provide an overview of the genetic tools and methods used to study ipRGCs, how these tools have been used to dissect their role in a variety of visual circuits and behaviors in mice, and identify important directions for future study.
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Affiliation(s)
- Marcos L Aranda
- Department of Neurobiology, Northwestern University, Evanston, IL, USA
| | - Tiffany M Schmidt
- Department of Neurobiology, Northwestern University, Evanston, IL, USA.
- Department of Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
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40
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Lee R, Tapia A, Kaladchibachi S, Grandner MA, Fernandez FX. Meta-analysis of light and circadian timekeeping in rodents. Neurosci Biobehav Rev 2021; 123:215-229. [PMID: 33513413 DOI: 10.1016/j.neubiorev.2020.12.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 12/12/2020] [Accepted: 12/17/2020] [Indexed: 12/19/2022]
Abstract
We conducted a meta-analysis of papers published over the past half-century (1964-2017) that quantified the phase-shifting effects of timed light exposure on rodent locomotor rhythms. Descriptive statistics were tabulated in order to explore the extent to which these studies were generalizable across species, sex, age, circadian timing, and light sources. Attempts at understanding photic resetting were primarily targeted at younger male animals, with particular emphases placed on characterizing the pacemaker systems of C57BL/6 mice and Syrian hamsters during the parts of their subjective night most sensitive to delivery of white-fluorescent light. With subsequent analyses restricted to these rodent models, we then assessed the relationship between luminous exposure (via broadspectrum emission) and phase-shifting through a series of linear regressions. Monotonically increasing illuminance-response functions were noted at most circadian times surveyed. In the aggregate, our results show that previous research conducted on light's regulation of circadian timekeeping has been skewed in design with respect to several important biological variables. This bias might limit translation of phototherapy-relevant data to women and older individuals.
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Affiliation(s)
- Robert Lee
- Department of Psychology, University of Arizona, Tucson, AZ, USA
| | - Amaris Tapia
- Department of Psychology, University of Arizona, Tucson, AZ, USA
| | | | - Michael A Grandner
- Sleep and Health Research Program, Department of Psychiatry, University of Arizona, Tucson, AZ, USA
| | - Fabian-Xosé Fernandez
- Department of Psychology, University of Arizona, Tucson, AZ, USA; Department of Neurology, University of Arizona, Tucson, AZ, USA; BIO5 and McKnight Brain Research Institutes, Tucson, AZ, USA.
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41
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Walker WH, Bumgarner JR, Walton JC, Liu JA, Meléndez-Fernández OH, Nelson RJ, DeVries AC. Light Pollution and Cancer. Int J Mol Sci 2020; 21:E9360. [PMID: 33302582 PMCID: PMC7764771 DOI: 10.3390/ijms21249360] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/04/2020] [Accepted: 12/06/2020] [Indexed: 01/03/2023] Open
Abstract
For many individuals in industrialized nations, the widespread adoption of electric lighting has dramatically affected the circadian organization of physiology and behavior. Although initially assumed to be innocuous, exposure to artificial light at night (ALAN) is associated with several disorders, including increased incidence of cancer, metabolic disorders, and mood disorders. Within this review, we present a brief overview of the molecular circadian clock system and the importance of maintaining fidelity to bright days and dark nights. We describe the interrelation between core clock genes and the cell cycle, as well as the contribution of clock genes to oncogenesis. Next, we review the clinical implications of disrupted circadian rhythms on cancer, followed by a section on the foundational science literature on the effects of light at night and cancer. Finally, we provide some strategies for mitigation of disrupted circadian rhythms to improve health.
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Affiliation(s)
- William H. Walker
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506, USA; (J.R.B.); (J.C.W.); (J.A.L.); (O.H.M.-F.); (R.J.N.); (A.C.D.)
| | - Jacob R. Bumgarner
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506, USA; (J.R.B.); (J.C.W.); (J.A.L.); (O.H.M.-F.); (R.J.N.); (A.C.D.)
| | - James C. Walton
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506, USA; (J.R.B.); (J.C.W.); (J.A.L.); (O.H.M.-F.); (R.J.N.); (A.C.D.)
| | - Jennifer A. Liu
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506, USA; (J.R.B.); (J.C.W.); (J.A.L.); (O.H.M.-F.); (R.J.N.); (A.C.D.)
| | - O. Hecmarie Meléndez-Fernández
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506, USA; (J.R.B.); (J.C.W.); (J.A.L.); (O.H.M.-F.); (R.J.N.); (A.C.D.)
| | - Randy J. Nelson
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506, USA; (J.R.B.); (J.C.W.); (J.A.L.); (O.H.M.-F.); (R.J.N.); (A.C.D.)
| | - A. Courtney DeVries
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506, USA; (J.R.B.); (J.C.W.); (J.A.L.); (O.H.M.-F.); (R.J.N.); (A.C.D.)
- Department of Medicine, Division of Oncology/Hematology, West Virginia University, Morgantown, WV 26506, USA
- West Virginia University Cancer Institute, West Virginia University, Morgantown, WV 26506, USA
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42
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Electrochromic selective filtering of chronodisruptive visible wavelengths. PLoS One 2020; 15:e0241900. [PMID: 33152042 PMCID: PMC7643985 DOI: 10.1371/journal.pone.0241900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 10/22/2020] [Indexed: 01/20/2023] Open
Abstract
We present evidence of pupil response modification, as well as differential theoretical melatonin suppression through selective and dynamic electrochromic filtering of visible light in the 400-500 nm range to minimize chronodisruptive nocturnal blue light exposure. A lower activation of intrinsically photosensitive retinal ganglion cells (ipRGCs), the first step for light to reach a human's internal clock, is related to melatonin secretion therefore avoiding detrimental effects of excessive blue light exposure. Pupillary Light Reflex and Color Naming were experimentally assessed under light filtered by two different coloration states (transmissive and absorptive) of these novel dynamic filters, plus an uncoated test device, in 16 volunteers. Also, different commercial light sources at illuminances ranging from 1 to 1000 lux were differentially filtered and compared in terms of theoretical melatonin suppression. Representative parameters of the pupil responses reflected lower pupil constriction when the electrochromic filters (ECFs) were switched on (absorptive state, blue light is absorbed by the filter) compared to uncoated filters (control sample), but failed to do so under transmissive state (blue light passes through the filter) indicating less activation of ipRGCs under absorptive state (although no significant differences between states was found). Out of eight colors tested, just one showed significant differences in naming between both filter states. Thus, the ECF would have some protecting effect on ipRGC activation with very limited changes in color perception. While there are some limitations of the theoretical model used, the absorptive state yielded significantly lower theoretical melatonin suppression in all those light sources containing blue wavelengths across the illuminance range tested. This would open the way for further research on biological applications of electrochromic devices.
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43
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Abstract
Cone photoreceptors in the retina are exposed to intense daylight and have higher energy demands in darkness. Cones produce energy using a large cluster of mitochondria. Mitochondria are susceptible to oxidative damage, and healthy mitochondrial populations are maintained by regular turnover. Daily cycles of light exposure and energy consumption suggest that mitochondrial turnover is important for cone health. We investigated the three-dimensional (3D) ultrastructure and metabolic function of zebrafish cone mitochondria throughout the day. At night retinas undergo a mitochondrial biogenesis event, corresponding to an increase in the number of smaller, simpler mitochondria and increased metabolic activity in cones. In the daytime, endoplasmic reticula (ER) and autophagosomes associate more with mitochondria, and mitochondrial size distribution across the cluster changes. We also report dense material shared between cone mitochondria that is extruded from the cell at night, sometimes forming extracellular structures. Our findings reveal an elaborate set of daily changes to cone mitochondrial structure and function.
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44
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Lee SK, Sonoda T, Schmidt TM. M1 Intrinsically Photosensitive Retinal Ganglion Cells Integrate Rod and Melanopsin Inputs to Signal in Low Light. Cell Rep 2020; 29:3349-3355.e2. [PMID: 31825819 PMCID: PMC6951432 DOI: 10.1016/j.celrep.2019.11.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 09/04/2019] [Accepted: 11/06/2019] [Indexed: 02/01/2023] Open
Abstract
Light influences various behaviors and physiological processes that occur outside of our conscious perception, including circadian photoentrainment, sleep, and even learning and mood. The M1, melanopsin-expressing, intrinsically photosensitive retinal ganglion cells (ipRGCs) relay a combination of rod/cone and melanopsin signals to drive these functions. However, little is known about how M1 ipRGCs integrate these signals in low light. We measure the dim light response of M1 ipRGCs and find that they exhibit a wide spectrum of responses to dim, scotopic light stimulation that are driven by a combination of rod pathway input and melanopsin phototransduction. The presence of rod input to M1 ipRGCs correlates with larger and more complex dendritic arbors. Collectively, these results show variability in the rod input to M1 ipRGCs and a surprising contribution of melanopsin to the light responses of M1 ipRGCs at very low light. M1 intrinsically photosensitive retinal ganglion cells (ipRGCs) control an array of non-image-forming functions. Lee et al. report diverse light responses of M1 ipRGCs in scotopic light that are determined by the degree of rod and melanopsin inputs and find that degree of rod input correlates with dendritic complexity.
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Affiliation(s)
- Seul Ki Lee
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA
| | - Takuma Sonoda
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA
| | - Tiffany M Schmidt
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA.
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45
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Mouland JW, Martial F, Watson A, Lucas RJ, Brown TM. Cones Support Alignment to an Inconsistent World by Suppressing Mouse Circadian Responses to the Blue Colors Associated with Twilight. Curr Biol 2020; 29:4260-4267.e4. [PMID: 31846668 PMCID: PMC6926481 DOI: 10.1016/j.cub.2019.10.028] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/19/2019] [Accepted: 10/16/2019] [Indexed: 01/04/2023]
Abstract
In humans, short-wavelength light evokes larger circadian responses than longer wavelengths [1-3]. This reflects the fact that melanopsin, a key contributor to circadian assessments of light intensity, most efficiently captures photons around 480 nm [4-8] and gives rise to the popular view that "blue" light exerts the strongest effects on the clock. However, in the natural world, there is often no direct correlation between perceived color (as reported by the cone-based visual system) and melanopsin excitation. Accordingly, although the mammalian clock does receive cone-based chromatic signals [9], the influence of color on circadian responses to light remains unclear. Here, we define the nature and functional significance of chromatic influences on the mouse circadian system. Using polychromatic lighting and mice with altered cone spectral sensitivity (Opn1mwR), we generate conditions that differ in color (i.e., ratio of L- to S-cone opsin activation) while providing identical melanopsin and rod activation. When biased toward S-opsin activation (appearing "blue"), these stimuli reliably produce weaker circadian behavioral responses than those favoring L-opsin ("yellow"). This influence of color (which is absent in animals lacking cone phototransduction; Cnga3-/-) aligns with natural changes in spectral composition over twilight, where decreasing solar angle is accompanied by a strong blue shift [9-11]. Accordingly, we find that naturalistic color changes support circadian alignment when environmental conditions render diurnal variations in light intensity weak/ambiguous sources of timing information. Our data thus establish how color contributes to circadian entrainment in mammals and provide important new insight to inform the design of lighting environments that benefit health.
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Affiliation(s)
- Joshua W Mouland
- Centre for Biological Timing, Faculty of Biology, Medicine & Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Franck Martial
- Centre for Biological Timing, Faculty of Biology, Medicine & Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Alex Watson
- Centre for Biological Timing, Faculty of Biology, Medicine & Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Robert J Lucas
- Centre for Biological Timing, Faculty of Biology, Medicine & Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Timothy M Brown
- Centre for Biological Timing, Faculty of Biology, Medicine & Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK.
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46
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Szatko KP, Korympidou MM, Ran Y, Berens P, Dalkara D, Schubert T, Euler T, Franke K. Neural circuits in the mouse retina support color vision in the upper visual field. Nat Commun 2020; 11:3481. [PMID: 32661226 PMCID: PMC7359335 DOI: 10.1038/s41467-020-17113-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 04/21/2020] [Indexed: 02/06/2023] Open
Abstract
Color vision is essential for an animal’s survival. It starts in the retina, where signals from different photoreceptor types are locally compared by neural circuits. Mice, like most mammals, are dichromatic with two cone types. They can discriminate colors only in their upper visual field. In the corresponding ventral retina, however, most cones display the same spectral preference, thereby presumably impairing spectral comparisons. In this study, we systematically investigated the retinal circuits underlying mouse color vision by recording light responses from cones, bipolar and ganglion cells. Surprisingly, most color-opponent cells are located in the ventral retina, with rod photoreceptors likely being involved. Here, the complexity of chromatic processing increases from cones towards the retinal output, where non-linear center-surround interactions create specific color-opponent output channels to the brain. This suggests that neural circuits in the mouse retina are tuned to extract color from the upper visual field, aiding robust detection of predators and ensuring the animal’s survival. Mice are able to discriminate colors, at least in the upper visual field. Here, the authors provide a comprehensive characterization of retinal circuits underlying this behavior.
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Affiliation(s)
- Klaudia P Szatko
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Graduate Training Center of Neuroscience, International Max Planck Research School, University of Tübingen, Tübingen, Germany
| | - Maria M Korympidou
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Graduate Training Center of Neuroscience, International Max Planck Research School, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Yanli Ran
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Germany
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Katrin Franke
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany. .,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany. .,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.
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47
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Yoshimura M, Kitamura S, Eto N, Hida A, Katsunuma R, Ayabe N, Motomura Y, Nishiwaki Y, Negishi K, Tsubota K, Mishima K. Relationship between Indoor Daytime Light Exposure and Circadian Phase Response under Laboratory Free-Living Conditions. BIOL RHYTHM RES 2020. [DOI: 10.1080/09291016.2020.1782691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Michitaka Yoshimura
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Faculty of Human Health, Aichi Toho University, Nagoya, Japan
| | - Shingo Kitamura
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Norihito Eto
- Department of Biomedical Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - Akiko Hida
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Ruri Katsunuma
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Naoko Ayabe
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Yuki Motomura
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
- Department of Human Science, Faculty of Design, Kyushu University, Fukuoka, Japan
| | - Yuji Nishiwaki
- Department of Environmental and Occupational Health, School of Medicine, Toho University, Tokyo, Japan
| | - Kazuno Negishi
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuo Mishima
- Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
- Department of Neuropsychiatry, Akita University Graduate School of Medicine, Akita, Japan
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48
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Abstract
A small fraction of mammalian retinal ganglion cells are directly photoreceptive thanks to their expression of the photopigment melanopsin. These intrinsically photosensitive retinal ganglion cells (ipRGCs) have well-established roles in a variety of reflex responses to changes in ambient light intensity, including circadian photoentrainment. In this article, we review the growing evidence, obtained primarily from laboratory mice and humans, that the ability to sense light via melanopsin is also an important component of perceptual and form vision. Melanopsin photoreception has low temporal resolution, making it fundamentally biased toward detecting changes in ambient light and coarse patterns rather than fine details. Nevertheless, melanopsin can indirectly impact high-acuity vision by driving aspects of light adaptation ranging from pupil constriction to changes in visual circuit performance. Melanopsin also contributes directly to perceptions of brightness, and recent data suggest that this influences the appearance not only of overall scene brightness, but also of low-frequency patterns.
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Affiliation(s)
- Robert J Lucas
- Centre for Biological Timing and Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom;
| | - Annette E Allen
- Centre for Biological Timing and Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom;
| | - Nina Milosavljevic
- Centre for Biological Timing and Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom;
| | - Riccardo Storchi
- Centre for Biological Timing and Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom;
| | - Tom Woelders
- Centre for Biological Timing and Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom;
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49
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Andreatta G, Tessmar-Raible K. The Still Dark Side of the Moon: Molecular Mechanisms of Lunar-Controlled Rhythms and Clocks. J Mol Biol 2020; 432:3525-3546. [PMID: 32198116 PMCID: PMC7322537 DOI: 10.1016/j.jmb.2020.03.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/18/2020] [Accepted: 03/09/2020] [Indexed: 12/22/2022]
Abstract
Starting with the beginning of the last century, a multitude of scientific studies has documented that the lunar cycle times behaviors and physiology in many organisms. It is plausible that even the first life forms adapted to the different rhythms controlled by the moon. Consistently, many marine species exhibit lunar rhythms, and also the number of documented "lunar-rhythmic" terrestrial species is increasing. Organisms follow diverse lunar geophysical/astronomical rhythms, which differ significantly in terms of period length: from hours (circalunidian and circatidal rhythms) to days (circasemilunar and circalunar cycles). Evidence for internal circatital and circalunar oscillators exists for a range of species based on past behavioral studies, but those species with well-documented behaviorally free-running lunar rhythms are not typically used for molecular studies. Thus, the underlying molecular mechanisms are largely obscure: the dark side of the moon. Here we review findings that start to connect molecular pathways with moon-controlled physiology and behaviors. The present data indicate connections between metabolic/endocrine pathways and moon-controlled rhythms, as well as interactions between circadian and circatidal/circalunar rhythms. Moreover, recent high-throughput analyses provide useful leads toward pathways, as well as molecular markers. However, for each interpretation, it is important to carefully consider the, partly substantially differing, conditions used in each experimental paradigm. In the future, it will be important to use lab experiments to delineate the specific mechanisms of the different solar- and lunar-controlled rhythms, but to also start integrating them together, as life has evolved equally long under rhythms of both sun and moon.
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Affiliation(s)
- Gabriele Andreatta
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria; Research Platform "Rhythms of Life", University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Kristin Tessmar-Raible
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria; Research Platform "Rhythms of Life", University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria.
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50
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Chen NS, Ingram NT, Frederiksen R, Sampath AP, Chen J, Fain GL. Diminished Cone Sensitivity in cpfl3 Mice Is Caused by Defective Transducin Signaling. Invest Ophthalmol Vis Sci 2020; 61:26. [PMID: 32315379 PMCID: PMC7401474 DOI: 10.1167/iovs.61.4.26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Purpose Cone photoreceptor function loss 3 (Gnat2cpfl3/cpfl3 or cpfl3) is a mouse model commonly used as a functional cones null from a naturally occurring mutation in the α-subunit of cone transducin (Gnat2). We nevertheless detected robust cone-mediated light responses from cpfl3 animals, which we now explore. Methods Recordings were made from whole retina and from identified cones with whole-cell patch clamp in retinal slices. Relative levels of GNAT2 protein and numbers of cones in isolated retinas were compared between cpfl3, rod transducin knockout (Gnat1-/-), cpfl3/Gnat1-/- double mutants, and control C57Bl/6J age-matched mice at 4, 9, and 14 weeks of age. Results Cones from cpfl3 and cpfl3/Gnat1-/- mice 2 to 3 months of age displayed normal dark currents but greatly reduced sensitivity and amplification constants. Responses decayed more slowly than in control (C57Bl/6J) mice, indicating an altered mechanism of inactivation. At dim light intensities rod responses could be recorded from cpfl3 cones, indicating intact rod/cone gap junctions. The cpfl3 and cpfl3/Gnat1-/- mice express two-fold less GNAT2 protein compared with C57 at 4 weeks, and a four-fold decrease by 14 weeks. This is accompanied by a small decrease in the number of cones. Conclusions Cplf3 cones can respond to light with currents of normal amplitude and cannot be assumed to be a Gnat2 null. The decreased sensitivity and amplification rate of cones is not explained by a reduction in GNAT2 protein level, but instead by abnormal interactions of the mutant transducin with rhodopsin and the effector molecule, cGMP phosphodiesterase.
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Affiliation(s)
- Natalie S. Chen
- Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, United States
| | - Norianne T. Ingram
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, Los Angeles, California, United States,Department of Integrative Biology and Physiology, University of California, Los Angeles, California,United States
| | - Rikard Frederiksen
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, Los Angeles, California, United States
| | - Alapakkam P. Sampath
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, Los Angeles, California, United States
| | - Jeannie Chen
- Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, United States
| | - Gordon L. Fain
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, Los Angeles, California, United States,Department of Integrative Biology and Physiology, University of California, Los Angeles, California,United States
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