1
|
Spitschan M. Selecting, implementing and evaluating control and placebo conditions in light therapy and light-based interventions. Ann Med 2024; 56:2298875. [PMID: 38329797 PMCID: PMC10854444 DOI: 10.1080/07853890.2023.2298875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 12/20/2023] [Indexed: 02/09/2024] Open
Abstract
Introduction: Light profoundly influences human physiology, behaviour and cognition by affecting various functions through light-sensitive cells in the retina. Light therapy has proven effective in treating seasonal depression and other disorders. However, designing appropriate control conditions for light-based interventions remains a challenge.Materials and methods: This article presents a novel framework for selecting, implementing and evaluating control conditions in light studies, offering theoretical foundations and practical guidance. It reviews the fundamentals of photoreception and discusses control strategies such as dim light, darkness, different wavelengths, spectral composition and metameric conditions. Special cases like dynamic lighting, simulated dawn and dusk, complex interventions and studies involving blind or visually impaired patients are also considered.Results: The practical guide outlines steps for selection, implementation, evaluation and reporting, emphasizing the importance of α-opic calculations and physiological validation.Conclusion: In conclusion, constructing effective control conditions is crucial for demonstrating the efficacy of light interventions in various research scenarios.
Collapse
Affiliation(s)
- Manuel Spitschan
- Max Planck Institute for Biological Cybernetics, Translational Sensory & Circadian Neuroscience, Tübingen, Germany
- Technical University of Munich, TUM School of Medicine and Health, Chronobiology & Health, Munich, Germany
- Technical University of Munich, TUM Institute for Advanced Study (TUM-IAS), Garching, Germany
| |
Collapse
|
2
|
Bansal H, Pyari G, Roy S. Theoretical prediction of broadband ambient light optogenetic vision restoration with ChRmine and its mutants. Sci Rep 2024; 14:11642. [PMID: 38773346 PMCID: PMC11109128 DOI: 10.1038/s41598-024-62558-2] [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: 12/05/2023] [Accepted: 05/18/2024] [Indexed: 05/23/2024] Open
Abstract
Vision restoration is one of the most promising applications of optogenetics. However, it is limited due to the poor-sensitivity, slow-kinetics and narrow band absorption spectra of opsins. Here, a detailed theoretical study of retinal ganglion neurons (RGNs) expressed with ChRmine, ReaChR, CoChR, CatCh and their mutants, with near monochromatic LEDs, and broadband sunlight, halogen lamp, RGB LED light, and pure white light sources has been presented. All the opsins exhibit improved light sensitivity and larger photocurrent on illuminating with broadband light sources compared to narrow band LEDs. ChRmine allows firing at ambient sunlight (1.5 nW/mm2) and pure white light (1.2 nW/mm2), which is lowest among the opsins considered. The broadband activation spectrum of ChRmine and its mutants is also useful to restore color sensitivity. Although ChRmine exhibits slower turn-off kinetics with broadband light, high-fidelity spikes can be evoked upto 50 Hz. This limit extends upto 80 Hz with the improved hsChRmine mutant although it requires double the irradiance compared to ChRmine. The present study shows that ChRmine and its mutants allow activation of RGNs with ambient light which is useful for goggle-free white light optogenetic retinal prostheses with improved quality of restored vision.
Collapse
Affiliation(s)
- Himanshu Bansal
- Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra, 282005, India
| | - Gur Pyari
- Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra, 282005, India
| | - Sukhdev Roy
- Department of Physics and Computer Science, Dayalbagh Educational Institute, Agra, 282005, India.
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
Bessman SC, Harrison EM, Easterling AP, Snider MN, Preilipper SMM, Glickman GL. Hybrid effectiveness-implementation study of two novel spectrally engineered lighting interventions for shiftworkers on a high-security watchfloor. SLEEP ADVANCES : A JOURNAL OF THE SLEEP RESEARCH SOCIETY 2023; 4:zpad051. [PMID: 38084298 PMCID: PMC10710545 DOI: 10.1093/sleepadvances/zpad051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/13/2023] [Indexed: 06/26/2024]
Abstract
Shiftwork leads to myriad negative health and safety outcomes. Lighting countermeasures can benefit shiftworkers via physiological effects of light (e.g. alerting, circadian adjustment), and short-wavelength light is the most potent for eliciting those responses; however, limited work indicates it may not be required for alerting. We developed similar-appearing light boxes (correlated color temperature: 3000-3375 K; photopic illuminance: 260-296 lux), enriched (SW+, melanopic EDI: 294 lux) or attenuated (SW-, melanopic EDI: 103 lux) in short-wavelength energy, and implemented them on a high-security watchfloor. Efficacy and feasibility of these two novel lighting interventions were assessed in personnel working 12-hour night shifts (n = 47) in this within-participants, crossover study. For each intervention condition, light boxes were arranged across the front of the watchfloor and illuminated the entire shift; blue-blocking glasses were worn post-shift and before sleep; and sleep masks were used while sleeping. Comparisons between baseline and intervention conditions included alertness, sleep, mood, quality of life (QOL), and implementation measures. On-shift alertness (Karolinska Sleepiness Scale) increased in SW- compared to baseline, while changes in SW+ were more limited. Under SW+, both mood and sleep improved. Psychomotor vigilance task performance did not vary by condition; however, perceived performance and QOL were higher, and reported caffeine consumption and sleep onset latency were lower, under SW-. For both interventions, satisfaction and comfort were high, and fewer symptoms and negative feelings were reported. The addition of spectrally engineered lights to this unique work environment improved sleep, alertness, and mood without compromising visual comfort and satisfaction. This paper is part of the Sleep and Circadian Rhythms: Management of Fatigue in Occupational Settings Collection.
Collapse
Affiliation(s)
- Sara C Bessman
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, USA
- Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, USA
| | - Elizabeth M Harrison
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, USA
- Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, USA
| | - Alexandra P Easterling
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, USA
- Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, USA
| | - Michelle N Snider
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, USA
- Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, USA
| | - Sebastian M M Preilipper
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF), Bethesda, USA
- Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, USA
| | - Gena L Glickman
- Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, USA
| |
Collapse
|
5
|
Zielinska-Dabkowska KM, Schernhammer ES, Hanifin JP, Brainard GC. Reducing nighttime light exposure in the urban environment to benefit human health and society. Science 2023; 380:1130-1135. [PMID: 37319219 DOI: 10.1126/science.adg5277] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023]
Abstract
Nocturnal light pollution can have profound effects on humans and other organisms. Recent research indicates that nighttime outdoor lighting is increasing rapidly. Evidence from controlled laboratory studies demonstrates that nocturnal light exposure can strain the visual system, disrupt circadian physiology, suppress melatonin secretion, and impair sleep. There is a growing body of work pointing to adverse effects of outdoor lighting on human health, including the risk of chronic diseases, but this knowledge is in a more nascent stage. In this Review, we synthesize recent research on the context-specific factors and physiology relevant to nocturnal light exposure in relation to human health and society, identify critical areas for future research, and highlight recent policy steps and recommendations for mitigating light pollution in the urban environment.
Collapse
Affiliation(s)
- K M Zielinska-Dabkowska
- GUT LightLab Department of Architecture, Gdańsk University of Technology, 80-233 Gdańsk, Poland
| | - E S Schernhammer
- Department of Epidemiology, Center for Public Health, Medical University of Vienna, Vienna, 1090, Austria
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA 02115, USA
| | - J P Hanifin
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - G C Brainard
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| |
Collapse
|
6
|
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.
Collapse
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.
| |
Collapse
|
7
|
Baz ES, Hussein AAA, Vreeker EMT, Soliman MFM, Tadros MM, El-Shenawy NS, Koene JM. Consequences of artificial light at night on behavior, reproduction, and development of Lymnaea stagnalis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 307:119507. [PMID: 35609841 DOI: 10.1016/j.envpol.2022.119507] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/30/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
Light is an important zeitgeber that regulates many behavioral and physiological processes in animals. These processes may become disturbed due to the changes in natural patterns of light and dark via the introduction of artificial light at night (ALAN). The present study was designed to determine the effect of possible consequences of ALAN on reproduction, hatching success, developmental success, growth rate, feeding rate, mortality rate, and locomotor activity of the simultaneous hermaphrodite pond snail Lymnaea stagnalis. Snails were exposed to different light intensities at night that simulate actual ALAN measurements from the snail's night environment. The data revealed that exposure to ALAN at a low level significantly affected the cumulative number of laid eggs. At the same time, snails exposed to ALAN laid smaller eggs than those laid under normal light-dark cycles. Additionally, high light-intensity of ALAN delayed development and hatching of eggs of L. stagnalis while it showed no effect on hatching percentage. Furthermore, ALAN increased both the feeding and growth rates but did not lead to mortality. The results also show that snails exposed to dark conditions at night travel longer distances and do so faster than those exposed to ALAN. In light of these findings, it is clear that ALAN may have an influence on snails and their abundance in an environment, possibly disturbing ecological stability.
Collapse
Affiliation(s)
- El-Sayed Baz
- Zoology Department, Faculty of Science, Suez Canal University, 41522, Ismailia, Egypt
| | - Ahmed A A Hussein
- Zoology Department, Faculty of Science, Suez Canal University, 41522, Ismailia, Egypt; Department of Ecological Science, Faculty of Science, Vrije Universiteit, De Boelelaan 1085, 1081, Amsterdam, the Netherlands; Department of Malacology, Theodor Bilharz Research Institute (TBRI), 30 Imbaba, 12411, Giza, Egypt.
| | - Edith M T Vreeker
- Department of Ecological Science, Faculty of Science, Vrije Universiteit, De Boelelaan 1085, 1081, Amsterdam, the Netherlands
| | - Maha F M Soliman
- Zoology Department, Faculty of Science, Suez Canal University, 41522, Ismailia, Egypt
| | - Menerva M Tadros
- Department of Malacology, Theodor Bilharz Research Institute (TBRI), 30 Imbaba, 12411, Giza, Egypt
| | - Nahla S El-Shenawy
- Zoology Department, Faculty of Science, Suez Canal University, 41522, Ismailia, Egypt
| | - Joris M Koene
- Department of Ecological Science, Faculty of Science, Vrije Universiteit, De Boelelaan 1085, 1081, Amsterdam, the Netherlands
| |
Collapse
|
8
|
Spitschan M, Mead J, Roos C, Lowis C, Griffiths B, Mucur P, Herf M, Nam S, Veitch JA. luox: validated reference open-access and open-source web platform for calculating and sharing physiologically relevant quantities for light and lighting. Wellcome Open Res 2022; 6:69. [PMID: 34017925 PMCID: PMC8095192 DOI: 10.12688/wellcomeopenres.16595.3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/06/2022] [Indexed: 11/22/2023] Open
Abstract
Light exposure has a profound impact on human physiology and behaviour. For example, light exposure at the wrong time can disrupt our circadian rhythms and acutely suppress the production of melatonin. In turn, appropriately timed light exposure can support circadian photoentrainment. Beginning with the discovery that melatonin production is acutely suppressed by bright light more than 40 years ago, understanding which aspects of light drive the 'non-visual' responses to light remains a highly active research area, with an important translational dimension and implications for "human-centric" or physiologically inspired architectural lighting design. In 2018, the International Commission on Illumination (CIE) standardised the spectral sensitivities for predicting the non-visual effects of a given spectrum of light with respect to the activation of the five photoreceptor classes in the human retina: the L, M and S cones, the rods, and the melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs). Here, we described a novel, lean, user-friendly, open-access and open-source platform for calculating quantities related to light. The platform, called luox, enables researchers and research users in vision science, lighting research, chronobiology, sleep research and adjacent fields to turn spectral measurements into reportable quantities. The luox code base, released under the GPL-3.0 License, is modular and therefore extendable to other spectrum-derived quantities. luox calculations of CIE quantities and indices have been endorsed by the CIE following black-box validation.
Collapse
Affiliation(s)
- Manuel Spitschan
- Department of Experimental Psychology, University of Oxford, Oxford, UK
- Sleep and Circadian Neuroscience Institute (SCNi), University of Oxford, Oxford, UK
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
- TUM Department of Sport and Health Sciences (TUM SG), Chronobiology & Health, Technical University of Munich, Munich, Germany
- Max Planck Institute for Biological Cybernetics, Translational Sensory & Circadian Neuroscience, Tübingen, Germany
- TUM Institute for Advanced Study (TUM-IAS), Technical University of Munich, Garching, Germany
| | | | | | | | | | | | | | - Somang Nam
- National Research Council of Canada, Construction Research Centre, Ottawa, Canada
| | - Jennifer A. Veitch
- National Research Council of Canada, Construction Research Centre, Ottawa, Canada
| |
Collapse
|
9
|
Dim Blue Light at Night Induces Spatial Memory Impairment in Mice by Hippocampal Neuroinflammation and Oxidative Stress. Antioxidants (Basel) 2022; 11:antiox11071218. [PMID: 35883709 PMCID: PMC9311634 DOI: 10.3390/antiox11071218] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/12/2022] [Accepted: 06/17/2022] [Indexed: 12/04/2022] Open
Abstract
Light pollution is one of the most serious public problems, especially the night light. However, the effect of dim blue light at night (dLAN-BL) on cognitive function is unclear. In this study, we evaluated the effects of exposure to dLAN-BL in C57BL/6J mice for 4 consecutive weeks. Our results showed dLAN-BL significantly impaired spatial learning and memory and increased plasma corticosterone level in mice. Consistent with these changes, we observed dLAN-BL significantly increased the numbers and activation of microglia and the levels of oxidative stress product MDA in the hippocampus, decreased the levels of antioxidant enzymes Glutathione peroxidase (GSH-Px), Superoxide dismutase (SOD), Gluathione reductase (Gsr), total antioxidants (T-AOC) and the number of neurons in the hippocampus, up-regulated the mRNA expression levels of IL6, TNF-α and the protein expression levels of iNOS, COX2, TLR4, p-p65, Cleaved-Caspase3 and BAX, and down-regulated the mRNA expression levels of IL4, IL10, Psd95, Snap25, Sirt1, Dcx and the protein expression level of BCL2. In vitro results further showed corticosterone (10uM)-induced BV2 cell activation and up-regulated content of IL6, TNF-α in the cell supernatant and the protein expression levels of iNOS, COX2, p-p65 in BV2 cells. Our findings suggested dLAN-BL up-regulated plasma corticosterone level and hippocampal microglia activation, which in turn caused oxidative stress and neuroinflammation, leading to neuronal loss and synaptic dysfunction, ultimately leading to spatial learning and memory dysfunction in mice.
Collapse
|
10
|
Nocturnal Lifestyle Behaviours and Risk of Poor Sleep during Pregnancy. Nutrients 2022; 14:nu14112348. [PMID: 35684148 PMCID: PMC9182878 DOI: 10.3390/nu14112348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 05/30/2022] [Accepted: 06/02/2022] [Indexed: 02/04/2023] Open
Abstract
The extent to which lifestyle practices at night influence sleep quality in pregnant women remains unknown. This study aimed to examine whether nocturnal behaviours were associated with poor sleep during pregnancy. We performed a cross-sectional analysis of a prospective cohort of pregnant women at 18–24 gestation weeks recruited from KK Women’s and Children’s Hospital, Singapore, between 2019 and 2021. Nocturnal behaviours were assessed with questionnaires, and sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) with a global score ≥5 indicative of poor sleep quality. Modified Poisson regression and linear regression were used to examine the association between nocturnal behaviour and sleep quality. Of 299 women, 117 (39.1%) experienced poor sleep. In the covariate-adjusted analysis, poor sleep was observed in women with nocturnal eating (risk ratio 1.51; 95% confidence interval [CI] 1.12, 2.04) and nocturnal artificial light exposure (1.63; 1.24, 2.13). Similarly, nocturnal eating (β 0.68; 95% CI 0.03, 1.32) and light exposure (1.99; 1.04, 2.94) were associated with higher PSQI score. Nocturnal physical activity and screen viewing before bedtime were not associated with sleep quality. In conclusion, reducing nocturnal eating and light exposure at night could potentially improve sleep in pregnancy.
Collapse
|
11
|
Aulsebrook AE, Jechow A, Krop-Benesch A, Kyba CCM, Longcore T, Perkin EK, van Grunsven RHA. Nocturnal lighting in animal research should be replicable and reflect relevant ecological conditions. Biol Lett 2022; 18:20220035. [PMID: 35291885 PMCID: PMC8923816 DOI: 10.1098/rsbl.2022.0035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In nature, light is a key driver of animal behaviour and physiology. When studying captive or laboratory animals, researchers usually expose animals to a period of darkness, to mimic night. However, ‘darkness’ is often poorly quantified and its importance is generally underappreciated in animal research. Even small differences in nocturnal light conditions can influence biology. When light levels during the dark phase are not reported accurately, experiments can be impossible to replicate and compare. Furthermore, when nocturnal light levels are unrealistically dark or bright, the research is less ecologically relevant. Such issues are exacerbated by huge differences in the sensitivity of different light meters, which are not always described in study methods. We argue that nocturnal light levels need to be reported clearly and precisely, particularly in studies of animals housed indoors (e.g. ‘<0.03 lux’ rather than ‘0 lux’ or ‘dark’), and that these light levels should reflect conditions that the animal would experience in a natural context.
Collapse
Affiliation(s)
- Anne E Aulsebrook
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Seewiesen, Germany
| | - Andreas Jechow
- Community and Ecosystem Ecology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.,Remote Sensing and Geoinformatics, GFZ German Centre for Geosciences, Potsdam, Germany
| | | | - Christopher C M Kyba
- Remote Sensing and Geoinformatics, GFZ German Centre for Geosciences, Potsdam, Germany
| | - Travis Longcore
- UCLA Institute of the Environment and Sustainability, Los Angeles, CA, USA
| | | | - Roy H A van Grunsven
- Dutch Butterfly Conservation, Mennonietenweg 10, 6702 AD, Wageningen, The Netherlands
| |
Collapse
|
12
|
Design and implementation of an illumination system to mimic skyglow at ecosystem level in a large-scale lake enclosure facility. Sci Rep 2021; 11:23478. [PMID: 34873189 PMCID: PMC8648721 DOI: 10.1038/s41598-021-02772-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 11/17/2021] [Indexed: 11/18/2022] Open
Abstract
Light pollution is an environmental stressor of global extent that is growing exponentially in area and intensity. Artificial skyglow, a form of light pollution with large range, is hypothesized to have environmental impact at ecosystem level. However, testing the impact of skyglow at large scales and in a controlled fashion under in situ conditions has remained elusive so far. Here we present the first experimental setup to mimic skyglow at ecosystem level outdoors in an aquatic environment. Spatially diffuse and homogeneous surface illumination that is adjustable between 0.01 and 10 lx, resembling rural to urban skyglow levels, was achieved with white light-emitting diodes at a large-scale lake enclosure facility. The illumination system was enabled by optical modeling with Monte-Carlo raytracing and validated by measurements. Our method can be adapted to other outdoor and indoor skyglow experiments, urgently needed to understand the impact of skyglow on ecosystems.
Collapse
|
13
|
Chen YR, Wei WL, Tzeng DTW, Owens ACS, Tang HC, Wu CS, Lin SS, Zhong S, Yang EC. Effects of artificial light at night (ALAN) on gene expression of Aquatica ficta firefly larvae. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 281:116944. [PMID: 33813192 DOI: 10.1016/j.envpol.2021.116944] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 03/09/2021] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
Artificial light at night (ALAN) is a major driver of firefly population declines, but its physiological effects are not well understood. To investigate the impact of ALAN on firefly development, we exposed larval Aquatica ficta fireflies to ALAN for two weeks. High larval mortality was observed in the periods of 1-68 days and 106-134 days post-treatment, which may represent the short- and long-term impacts of ALAN. We then profiled the transcriptome of larval Aquatica ficta fireflies following two weeks of ALAN exposure. A total of 1262 (1.67% out of 75777 unigenes) were differentially expressed in the treatment group: 1157 were down-regulated, and 105 were up-regulated. Up-regulated unigenes were related to regulation of hormone levels, ecdysteroid metabolic process, and response to stimulus; down-regulated unigenes were related to negative regulation of insulin receptor signaling, germ cell development, oogenesis, spermatid development, and regulation of neuron differentiation. Transcriptome results suggest that the endocrine, reproductive, and neural development of firefly larvae could be impaired by even relatively brief period of ALAN exposure. This report contributes a much-needed molecular perspective to the growing body of research documenting the fitness impacts of ALAN on bioluminescent fireflies.
Collapse
Affiliation(s)
- Yun-Ru Chen
- Department of Entomology, National Taiwan University, Taiwan
| | - Wei-Lun Wei
- Institute of Biotechnology, National Taiwan University, Taiwan
| | - David T W Tzeng
- School of Life Sciences, The Chinese University of Hong Kong, China
| | | | | | | | - Shih-Shun Lin
- Institute of Biotechnology, National Taiwan University, Taiwan
| | - Silin Zhong
- School of Life Sciences, The Chinese University of Hong Kong, China
| | - En-Cheng Yang
- Department of Entomology, National Taiwan University, Taiwan.
| |
Collapse
|
14
|
Spitschan M, Mead J, Roos C, Lowis C, Griffiths B, Mucur P, Herf M. luox: novel validated open-access and open-source web platform for calculating and sharing physiologically relevant quantities for light and lighting. Wellcome Open Res 2021; 6:69. [PMID: 34017925 PMCID: PMC8095192 DOI: 10.12688/wellcomeopenres.16595.2] [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] [Accepted: 06/01/2021] [Indexed: 12/16/2022] Open
Abstract
Light exposure has a profound impact on human physiology and behaviour. For example, light exposure at the wrong time can disrupt our circadian rhythms and acutely suppress the production of melatonin. In turn, appropriately timed light exposure can support circadian photoentrainment. Beginning with the discovery that melatonin production is acutely suppressed by bright light more than 40 years ago, understanding which aspects of light drive the 'non-visual' responses to light remains a highly active research area, with an important translational dimension and implications for "human-centric" or physiologically inspired architectural lighting design. In 2018, the International Commission on Illumination (CIE) standardised the spectral sensitivities for predicting the non-visual effects of a given spectrum of light with respect to the activation of the five photoreceptor classes in the human retina: the L, M and S cones, the rods, and the melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs). Here, we described a novel, lean, user-friendly, open-access and open-source platform for calculating quantities related to light. The platform, called luox, enables researchers and research users in chronobiology, sleep research and adjacent field to turn spectral measurements into reportable quantities. The luox code base, released under the GPL-3.0 License, is modular and therefore extendable to other spectrum-derived quantities. luox has been endorsed by the CIE following black-box validation.
Collapse
Affiliation(s)
- Manuel Spitschan
- Department of Experimental Psychology, University of Oxford, Oxford, UK.,Sleep and Circadian Neuroscience Institute (SCNi), University of Oxford, Oxford, UK.,Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland.,Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
| | | | | | | | | | | | | |
Collapse
|
15
|
Spitschan M, Mead J, Roos C, Lowis C, Griffiths B, Mucur P, Herf M. luox: novel open-access and open-source web platform for calculating and sharing physiologically relevant quantities for light and lighting. Wellcome Open Res 2021; 6:69. [DOI: 10.12688/wellcomeopenres.16595.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2021] [Indexed: 11/20/2022] Open
Abstract
Light exposure has a profound impact on human physiology and behaviour. For example, light exposure at the wrong time can disrupt our circadian rhythms and acutely suppress the production of melatonin. In turn, appropriately timed light exposure can support circadian photoentrainment. Beginning with the discovery that melatonin production is acutely suppressed by bright light more than 40 years ago, understanding which aspects of light drive the 'non-visual' responses to light remains a highly active research area, with an important translational dimension and implications for "human-centric" or physiologically inspired architectural lighting design. In 2018, the International Commission on Illumination (CIE) standardised the spectral sensitivities for predicting the non-visual effects of a given spectrum of light with respect to the activation of the five photoreceptor classes in the human retina: the L, M and S cones, the rods, and the melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs). Here, we described a novel, lean, user-friendly, open-access and open-source platform for calculating quantities related to light. The platform, called luox, enables researchers and research users in chronobiology, sleep research and adjacent field to turn spectral measurements into reportable quantities. The luox code base, released under the GPL-3.0 License, is modular and therefore extendable to other spectrum-derived quantities.
Collapse
|