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Mitsui K, Saeki K, Sun M, Yamagami Y, Tai Y, Obayashi K. Effects of a violet-excitation light-emitting diode on melatonin secretion and sleepiness: preliminary findings from a randomized controlled trial. J Clin Sleep Med 2024; 20:101-109. [PMID: 37707296 PMCID: PMC10758554 DOI: 10.5664/jcsm.10814] [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] [Received: 03/03/2023] [Revised: 09/05/2023] [Accepted: 09/07/2023] [Indexed: 09/15/2023]
Abstract
STUDY OBJECTIVES A new type of lighting using violet-excitation light-emitting diodes (LEDs) with an action spectrum centered at approximately 405 nm was developed. Although violet-excitation LEDs can reduce melatonin suppression compared with blue-excitation LEDs, no studies have compared the effects of violet-excitation LEDs with those of blue-excitation LEDs on melatonin suppression. This study was designed to compare the effects of violet-excitation LEDs with those of blue-excitation LEDs on melatonin suppression, psychomotor vigilance, and sleepiness. METHODS Sixteen healthy Japanese males aged 20-39 years were exposed to violet- and blue-excitation LEDs for 3 hours in a crossover randomized manner. The primary outcome was changes in salivary melatonin levels compared with the baseline levels. The secondary outcomes were changes in psychomotor vigilance and the Karolinska Sleepiness Scale. Melatonin suppression was calculated from the difference in the area under the curves between the baseline and intervention. RESULTS Of the 16 participants, 15 completed the measurements. The baseline characteristics did not differ significantly between the 2 groups. After adjusting for age, a difference of 16.28 pg/mL in mean melatonin suppression was observed between the violet- and blue-excitation LED groups (-2.15 pg/mL vs -18.43 pg/mL; P = .006). The overall melatonin suppression by violet-excitation LEDs was 48.6% smaller than that by blue-excitation LEDs. No significant differences in psychomotor vigilance and sleepiness were observed between the 2 groups. CONCLUSIONS Melatonin suppression in healthy Japanese males exposed to violet-excitation LEDs was significantly smaller than that in those exposed to blue-excitation LEDs. Our preliminary findings indicate that violet-excitation LEDs may have the potential to reduce the magnitude of blue-excitation LED-induced melatonin suppression. CITATION Mitsui K, Saeki K, Sun M, Yamagami Y, Tai Y, Obayashi K. Effects of a violet-excitation light-emitting diode on melatonin secretion and sleepiness: preliminary findings from a randomized controlled trial. J Clin Sleep Med. 2024;20(1):101-109.
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Affiliation(s)
- Katsuhiro Mitsui
- Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan
- Medical R&D Center, Corporate R&D Group, KYOCERA Corporation, Shiga, Japan
| | - Keigo Saeki
- Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan
| | - Mingyue Sun
- Medical R&D Center, Corporate R&D Group, KYOCERA Corporation, Shiga, Japan
| | - Yuki Yamagami
- Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan
| | - Yoshiaki Tai
- Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan
| | - Kenji Obayashi
- Department of Epidemiology, Nara Medical University School of Medicine, Nara, Japan
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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.
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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
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Zauner J, Broszio K, Bieske K. Influence of the Human Field of View on Visual and Non-Visual Quantities in Indoor Environments. Clocks Sleep 2023; 5:476-498. [PMID: 37754350 PMCID: PMC10530223 DOI: 10.3390/clockssleep5030032] [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: 06/13/2023] [Revised: 08/11/2023] [Accepted: 08/24/2023] [Indexed: 09/28/2023] Open
Abstract
The visual and non-visual effectiveness of light is often determined by measuring the spectrally weighed irradiance on the corneal plane. This is typically achieved using spectral irradiance or illuminance measurements, captured in a hemispheric (2π) geometry with a diffuser. However, the human binocular field of view (FOV) is not a perfect hemisphere, as it is occluded both upward and downward. Previous research on FOV-restricted measurements is limited, leaving the error from using hemispheric measurements for non-visual quantities undefined. In our study, we tackled this issue by designing and 3D printing FOV occlusions as attachments to spectral measurement devices. We took measurements with and without the occlusion in various laboratory (light from different directions) and real-world lighting situations (light typically from above). Our findings reveal a reduction of visual and melanopic values due to the FOV occlusion. These ranged from negligible to more than 60% in realistic scenarios. Interestingly, the reduction was consistent for both visual and melanopic parameters, as the distribution of light in the FOV was generally spectrally homogeneous. An exception occurred in a specific artificial laboratory situation, where the melanopic daylight (D65) efficacy ratio changed by more than a factor of 2 solely because of the FOV occlusion. Additionally, we observed that head orientation had a marked effect on all quantities measured. In conclusion, our results highlight the potential for substantial errors when solely relying on vertical, hemispheric measurements in experiments and non-visual lighting design projects. We encourage the (additional) use of FOV occlusion in eye-level measurements for typical viewing directions, and we are providing open-source 3D-print files to facilitate this practice.
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Affiliation(s)
- Johannes Zauner
- 3lpi Lichtplaner + Beratende Ingenieure mbB, Aidenbachstraße 52, 81379 Munich, Germany
- Munich University of Applied Sciences, Lothstraße 34, 80335 Munich, Germany
| | - Kai Broszio
- Federal Institute for Occupational Safety and Health (BAuA), Friedrich-Henkel-Weg 1-25, 44149 Dortmund, Germany
- Technische Universität Berlin, Einsteinufer 19, 10587 Berlin, Germany
| | - Karin Bieske
- Technische Universität Ilmenau, Ehrenbergstraße 29, 98693 Ilmenau, Germany;
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Collery A, Browne JA, O'Brien C, Sheridan JT, Murphy BA. Optimised Stable Lighting Strengthens Circadian Clock Gene Rhythmicity in Equine Hair Follicles. Animals (Basel) 2023; 13:2335. [PMID: 37508112 PMCID: PMC10376498 DOI: 10.3390/ani13142335] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
Hair follicles (HF) represent a useful tissue for monitoring the circadian clock in mammals. Irregular light exposure causes circadian disruption and represents a welfare concern for stabled horses. We aimed to evaluate the impact of two stable lighting regimes on circadian clock gene rhythmicity in HF from racehorses. Two groups of five Thoroughbred racehorses in training at a commercial racehorse yard were exposed to standard incandescent light or a customized LED lighting system. The control group received light from incandescent bulbs used according to standard yard practice. The treatment group received timed, blue-enriched white LED light by day and dim red LED light at night. On weeks 0 and 20, mane hairs were collected at 4 h intervals for 24 h. Samples were stored in RNAlater at -20 °C. RNA was isolated and samples interrogated by quantitative PCR for the core clock genes: ARNTL, CRY1, PER1, PER2, NR1D2, and the clock-controlled gene DBP. Cosinor analyses revealed 24 h rhythmicity for NR1D2 and PER2 and approached significance for CRY1 (p = 0.013, p = 0.013, and p = 0.051, respectively) in week 20 in the treatment group only. No rhythmicity was detected in week 0 or in week 20 in the HF of control horses. Results suggest that lighting practices in racehorse stables may be improved to better stimulate optimum functioning of the circadian system.
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Affiliation(s)
- Aileen Collery
- School of Agriculture and Food Science, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
| | - John A Browne
- School of Agriculture and Food Science, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
| | | | - John T Sheridan
- School of Electrical, Electronic and Mechanical Engineering, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
| | - Barbara A Murphy
- School of Agriculture and Food Science, University College Dublin, Belfield, D04 V1W8 Dublin, Co. Dublin, Ireland
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Wang W, Hao Z, Wu Z, Cui J, Liu H. Long-term artificial/natural daytime light affects mood, melatonin, corticosterone, and gut microbiota in rats. Appl Microbiol Biotechnol 2023; 107:2689-2705. [PMID: 36912904 DOI: 10.1007/s00253-023-12446-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 02/02/2023] [Accepted: 02/13/2023] [Indexed: 03/14/2023]
Abstract
The desynchronization of circadian rhythms affected by light may induce physiological and psychological disequilibrium. We aimed to elucidate changes of growth, depression-anxiety like behaviors, melatonin and corticosterone (CORT) secretion, and gut microbiota in rats influenced by long-term light inputs. Thirty male Sprague-Dawley rats were exposed to a 16/8 h light/dark regime for 8 weeks. The light period was set to 13 h of daylight with artificial light (AL group, n = 10), or with natural light (NL group, n = 10), or with mixed artificial-natural light (ANL group, n = 10), and 3 h of artificial night light after sunset. The obtained findings indicated that the highest weight gain and food efficiency were observed in the AL group and the lowest in NL group. In the behavioral tests, the NL and ANL groups showed lower anxiety level than AL group, and ANL groups showed lower depression level than AL group. The NL and ANL groups had delayed acrophases and maintained higher concentrations of melatonin compared to AL group. The circadian rhythm of CORT was only found in ANL group. At the phylum level, the mixed light contributed to a lower abundance of Bacteroidetes. The genus level results recommend a synergistic effect of artificial light and natural light on Lactobacillus abundance and an antagonistic effect on the Lachnospiraceae_NK4A136_group abundance. The study indicated that the mixture of artificial and natural light as well as the alignment of the proportions had beneficial influences on depression-anxiety-like levels, melatonin and corticosterone secretion, and the composition of the gut microbiota. KEY POINTS: • The mixed light can reduce the depression-anxiety level • The mixed light can maintain the secretion rhythm of melatonin and CORT • The mixed light can increase Lactobacillus and decrease Lachnospiraceae_NK4A136_group.
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Affiliation(s)
- Wei Wang
- Institute of Environmental Biology and Life Support Technology, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
- Institute of Medical Psychology, Faculty of Medicine, Ludwig-Maximilian-University of Munich, 80336, Munich, Germany
| | - Zikai Hao
- Key Laboratory of Molecular Medicine and Biotherapy, Ministry of Industry and Information Technology, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
| | - Zizhou Wu
- Institute of Environmental Biology and Life Support Technology, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Jingwei Cui
- Institute of Environmental Biology and Life Support Technology, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Hong Liu
- Institute of Environmental Biology and Life Support Technology, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China.
- International Joint Research Center of Aerospace Biotechnology & Medical Engineering, Beihang University, Beijing, 100083, China.
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Banerjee S, Ray S. Circadian medicine for aging attenuation and sleep disorders: Prospects and challenges. Prog Neurobiol 2023; 220:102387. [PMID: 36526042 DOI: 10.1016/j.pneurobio.2022.102387] [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: 08/21/2022] [Revised: 11/17/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022]
Abstract
Aging causes progressive deterioration of daily rhythms in behavioral and metabolic processes and disruption in the regular sleep-wake cycle. Circadian disruption is directly related to diverse age-induced health abnormalities. Rising evidence from various organisms shows that core clock gene mutations cause premature aging, reduced lifespan, and sleeping irregularities. Improving the clock functions and correcting its disruption by pharmacological interventions or time-regulated feeding patterns could be a novel avenue for effective clinical management of aging and sleep disorders. To this end, many drugs for sleep disorders and anti-aging compounds interact with the core clock machinery and alter the circadian output. Evaluation of dosing time-dependency and circadian regulation of drug metabolism for therapeutic improvement of the existing drugs is another fundamental facet of chronomedicine. Multiple studies have demonstrated dose-dependent manipulation of the circadian period and phase-shifting by pharmacologically active compounds. The chronobiology research field is gradually moving towards the development of novel therapeutic strategies based on targeting the molecular clock or dosing time-oriented medications. However, such translational research ventures would require more experimental evidence from studies on humans. This review discusses the impact of circadian rhythms on aging and sleep, emphasizing the potentiality of circadian medicine in aging attenuation and sleep disorders.
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Affiliation(s)
- Srishti Banerjee
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502284, Telangana, India
| | - Sandipan Ray
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502284, Telangana, India; Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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7
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Rahman SA, Kent BA, Grant LK, Clark T, Hanifin JP, Barger LK, Czeisler CA, Brainard GC, St Hilaire MA, Lockley SW. Effects of dynamic lighting on circadian phase, self-reported sleep and performance during a 45-day space analog mission with chronic variable sleep deficiency. J Pineal Res 2022; 73:e12826. [PMID: 35996978 PMCID: PMC11316501 DOI: 10.1111/jpi.12826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 07/29/2022] [Accepted: 08/20/2022] [Indexed: 10/15/2022]
Abstract
Spaceflight exposes crewmembers to circadian misalignment and sleep loss, which impair cognition and increase the risk of errors and accidents. We compared the effects of an experimental dynamic lighting schedule (DLS) with a standard static lighting schedule (SLS) on circadian phase, self-reported sleep and cognition during a 45-day simulated space mission. Sixteen participants (mean age [±SD] 37.4 ± 6.7 years; 5 F; n = 8/lighting condition) were studied in four-person teams at the NASA Human Exploration Research Analog. Participants were scheduled to sleep 8 h/night on two weekend nights, 5 h/night on five weekday nights, repeated for six 7-day cycles, with scheduled waketime fixed at 7:00 a.m. Compared to the SLS where illuminance and spectrum remained constant during wake (~4000K), DLS increased the illuminance and short-wavelength (blue) content of white light (~6000K) approximately threefold in the main workspace (Level 1), until 3 h before bedtime when illuminance was reduced by ~96% and the blue content also reduced throughout (~4000K × 2 h, ~3000K × 1 h) until bedtime. The average (±SE) urinary 6-sulphatoxymelatonin (aMT6s) acrophase time was significantly later in the SLS (6.22 ± 0.34 h) compared to the DLS (4.76 ± 0.53 h) and more variable in SLS compared to DLS (37.2 ± 3.6 min vs. 28.2 ± 2.4 min, respectively, p = .04). Compared to DLS, self-reported sleep was more frequently misaligned relative to circadian phase in SLS RR: 6.75, 95% CI 1.55-29.36, p = .01), but neither self-reported sleep duration nor latency to sleep was different between lighting conditions. Accuracy in the abstract matching and matrix reasoning tests were significantly better in DLS compared to SLS (false discovery rate-adjusted p ≤ .04). Overall, DLS alleviated the drift in circadian phase typically observed in space analog studies and reduced the prevalence of self-reported sleep episodes occurring at an adverse circadian phase. Our results support incorporating DLS in future missions, which may facilitate appropriate circadian alignment and reduce the risk of sleep disruption.
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Affiliation(s)
- Shadab A Rahman
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Brianne A Kent
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Leilah K Grant
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | | | - John P Hanifin
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA
| | - Laura K Barger
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Charles A Czeisler
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - George C Brainard
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA
| | - Melissa A St Hilaire
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Steven W Lockley
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
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Brown TM, Brainard GC, Cajochen C, Czeisler CA, Hanifin JP, Lockley SW, Lucas RJ, Münch M, O’Hagan JB, Peirson SN, Price LLA, Roenneberg T, Schlangen LJM, Skene DJ, Spitschan M, Vetter C, Zee PC, Wright KP. Recommendations for daytime, evening, and nighttime indoor light exposure to best support physiology, sleep, and wakefulness in healthy adults. PLoS Biol 2022; 20:e3001571. [PMID: 35298459 PMCID: PMC8929548 DOI: 10.1371/journal.pbio.3001571] [Citation(s) in RCA: 94] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Ocular light exposure has important influences on human health and well-being through modulation of circadian rhythms and sleep, as well as neuroendocrine and cognitive functions. Prevailing patterns of light exposure do not optimally engage these actions for many individuals, but advances in our understanding of the underpinning mechanisms and emerging lighting technologies now present opportunities to adjust lighting to promote optimal physical and mental health and performance. A newly developed, international standard provides a SI-compliant way of quantifying the influence of light on the intrinsically photosensitive, melanopsin-expressing, retinal neurons that mediate these effects. The present report provides recommendations for lighting, based on an expert scientific consensus and expressed in an easily measured quantity (melanopic equivalent daylight illuminance (melaponic EDI)) defined within this standard. The recommendations are supported by detailed analysis of the sensitivity of human circadian, neuroendocrine, and alerting responses to ocular light and provide a straightforward framework to inform lighting design and practice.
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Affiliation(s)
- Timothy M. Brown
- Centre for Biological Timing, 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
| | - Christian Cajochen
- Centre for Chronobiology, University Psychiatric Clinics Basel, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
| | - Charles A. Czeisler
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - John P. Hanifin
- Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Steven W. Lockley
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
- Surrey Sleep Research Centre, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Robert J. Lucas
- Centre for Biological Timing, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Mirjam Münch
- Centre for Chronobiology, University Psychiatric Clinics Basel, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
- Research Centre for Hauora and Health, Massey University, Wellington, New Zealand
| | - John B. O’Hagan
- Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, United Kingdom
| | - Stuart N. Peirson
- Sleep and Circadian Neuroscience Institute, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Luke L. A. Price
- Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, United Kingdom
| | - Till Roenneberg
- Institutes for Medical Psychology and Occupational, Social and Environmental Medicine, Medical Faculty, Ludwig-Maximilians University (LMU), Munich, Germany
| | - Luc J. M. Schlangen
- Human Technology Interaction Group, Department of Industrial Engineering and Innovation Sciences, Eindhoven University of Technology, Eindhoven, the Netherlands
- Intelligent Lighting Institute, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Debra J. Skene
- Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Manuel Spitschan
- Translational Sensory & 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
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Céline Vetter
- Circadian and Sleep Epidemiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, United States of America
| | - Phyllis C. Zee
- Department of Neurology, Northwestern University, Chicago, Illinois, United States of America
- Center for Circadian and Sleep Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Kenneth P. Wright
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, United States of America
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Giménez MC, Stefani O, Cajochen C, Lang D, Deuring G, Schlangen LJM. Predicting melatonin suppression by light in humans: Unifying photoreceptor-based equivalent daylight illuminances, spectral composition, timing and duration of light exposure. J Pineal Res 2022; 72:e12786. [PMID: 34981572 PMCID: PMC9285453 DOI: 10.1111/jpi.12786] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 12/30/2021] [Accepted: 12/30/2021] [Indexed: 12/23/2022]
Abstract
Light-induced melatonin suppression data from 29 peer-reviewed publications was analysed by means of a machine-learning approach to establish which light exposure characteristics (ie photopic illuminance, five α-opic equivalent daylight illuminances [EDIs], duration and timing of the light exposure, and the dichotomous variables pharmacological pupil dilation and narrowband light source) are the main determinants of melatonin suppression. Melatonin suppression in the data set was dominated by four light exposure characteristics: (1) melanopic EDI, (2) light exposure duration, (3) pupil dilation and (4) S-cone-opic EDI. A logistic model was used to evaluate the influence of each of these parameters on the melatonin suppression response. The final logistic model was only based on the first three parameters, since melanopic EDI was the best single (photoreceptor) predictor that was only outperformed by S-cone-opic EDI for (photopic) illuminances below 21 lux. This confirms and extends findings on the importance of the metric melanopic EDI for predicting biological effects of light in integrative (human-centric) lighting applications. The model provides initial and general guidance to lighting practitioners on how to combine spectrum, duration and amount of light exposure when controlling non-visual responses to light, especially melatonin suppression. The model is a starting tool for developing hypotheses on photoreceptors' contributions to light's non-visual responses and helps identifying areas where more data are needed, like on the S-cone contribution at low illuminances.
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Affiliation(s)
- Marina C. Giménez
- Chronobiology UnitGroningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Oliver Stefani
- Centre for Chronobiology and Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN)Psychiatric Hospital of the University of Basel (UPK) and University of BaselBaselSwitzerland
| | - Christian Cajochen
- Centre for Chronobiology and Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN)Psychiatric Hospital of the University of Basel (UPK) and University of BaselBaselSwitzerland
| | | | - Gunnar Deuring
- Forensic DepartmentUniversity Psychiatric Clinics BaselBaselSwitzerland
| | - Luc J. M. Schlangen
- Department of Industrial Engineering and Innovation SciencesHuman‐Technology Interaction Group and Intelligent Lighting InstituteEindhoven University of TechnologyEindhovenThe Netherlands
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Baptista E, André Arriel R, de Castro Carvalho AL, Bispo MMC, Rodrigues AB, Souza H, Mota GR, Marocolo M. Influence of Wearing Blue Lenses on Melatonin Production and
Performance in Volleyball Players. Sports Med Int Open 2022; 6:E1-E8. [PMID: 35211651 PMCID: PMC8860502 DOI: 10.1055/a-1720-6083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 12/05/2021] [Indexed: 11/29/2022] Open
Abstract
We analyzed the effects of wearing blue lenses on melatonin level, physical and
cognitive performance. Fifteen youth volleyball players
(15.0±1.5 yrs) attended the laboratory on 3 occasions (48-h
interval): on the 1
st
visit they were familiarized with the
procedures of the study, and on 2
nd
and 3
rd
visits they
were submitted to the testing protocol wearing transparent (control) or blue
lens glasses in a counterbalanced crossover design. The protocol consisted of
10 min in “total darkness,” 30 min of light
stimulation (wearing blue or transparent lenses), followed by an attentional
test, and an agility T-test (without wearing the glasses). Samples of saliva (to
determine melatonin concentration) were obtained pre- and post-exposure
(30 min) to artificial light, wearing the lenses. Sleepiness, alertness,
attention, mood, and perceived recovery status and performance variables
(reaction time and T-test) were assessed after lens exposure. Melatonin levels
did not differ within and between groups (blue lenses, pre: 0.79±0.73
and post: 1.19±1.374 pg/dl, p=0.252, effect size
(ES)=0.38; control, pre: 0.97±1.00 and post:
0.67±0.71 pg/dl, p=0.305,
ES=–0.35). Nonetheless, melatonin differences were significantly
correlated with physical sedation for glasses with blue lenses
(r=−0.526; p=0.04). No other variables differed
(p>0.05) between protocols, including T-test performance
(p=0.07; ES=0.41). Blue lenses do not influence melatonin
levels, cognitive/physical performance, and mood status in amateur youth
volleyball players.
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Affiliation(s)
- Eduardo Baptista
- Institute of Biological Sciences, Department of Physiology,
Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Rhai André Arriel
- Institute of Biological Sciences, Department of Physiology,
Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Ana Luiza de Castro Carvalho
- Institute of Biological Sciences, Department of Physiology,
Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Matheus M. C. Bispo
- Institute of Biological Sciences, Department of Physiology,
Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Alex Batista Rodrigues
- Institute of Biological Sciences, Department of Physiology,
Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Hiago Souza
- Institute of Biological Sciences, Department of Physiology,
Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
| | - Gustavo R. Mota
- Department of Sport Sciences/Institute of Health Sciences,
Federal University of Triangulo Mineiro, UBERABA, Brazil
| | - Moacir Marocolo
- Institute of Biological Sciences, Department of Physiology,
Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil
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11
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Short-wavelength light exposure at night and sleep disturbances accompanied by decreased melatonin secretion in real-life settings: a cross-sectional study of the HEIJO-KYO cohort. Sleep Med 2022; 90:192-198. [DOI: 10.1016/j.sleep.2022.01.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/18/2022] [Accepted: 01/26/2022] [Indexed: 11/18/2022]
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12
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Circadian photoreception: The impact of light on human circadian rhythms. PROGRESS IN BRAIN RESEARCH 2022; 273:171-180. [DOI: 10.1016/bs.pbr.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Spitschan M, Santhi N. Individual differences and diversity in human physiological responses to light. EBioMedicine 2022; 75:103640. [PMID: 35027334 PMCID: PMC8808156 DOI: 10.1016/j.ebiom.2021.103640] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/18/2021] [Accepted: 10/06/2021] [Indexed: 02/01/2023] Open
Abstract
Exposure to light affects our physiology and behaviour through a pathway connecting the retina to the circadian pacemaker in the hypothalamus - the suprachiasmatic nucleus (SCN). Recent research has identified significant individual differences in the non-visual effects of light,mediated by this pathway. Here, we discuss the fundamentals and individual differences in the non-visual effects of light. We propose a set of actions to improve our evidence database to be more diverse: understanding systematic bias in the evidence base, dedicated efforts to recruit more diverse participants, routine deposition and sharing of data, and development of data standards and reporting guidelines.
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Affiliation(s)
- Manuel Spitschan
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Department of Sport and Health Sciences, Technical University of Munich, Munich, Germany; Department of Experimental Psychology, University of Oxford, United Kingdom.
| | - Nayantara Santhi
- Department of Psychology, Northumbria University, United Kingdom.
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14
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Nie J, Zhou T, Chen Z, Dang W, Jiao F, Zhan J, Chen Y, Chen Y, Pan Z, Kang X, Wang Y, Wang Q, Tang Y, Dong W, Zhou S, Ma Y, Yu X, Zhang G, Shen B. The effects of dynamic daylight-like light on the rhythm, cognition, and mood of irregular shift workers in closed environment. Sci Rep 2021; 11:13059. [PMID: 34158564 PMCID: PMC8219698 DOI: 10.1038/s41598-021-92438-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 06/10/2021] [Indexed: 02/05/2023] Open
Abstract
Shift workers are mostly suffered from the disruption of circadian rhythm and health problems. In this study, we designed proper light environment to maintain stable circadian rhythm, cognitive performance, and mood status of shift workers. We used five-channel light-emitting diodes to build up the dynamic daylight-like light environment. The illuminance, correlated color temperature, and circadian action factor of light were tunable in the ranges of 226 to 678 lx, 2680 to 7314 K, and 0.32 to 0.96 throughout the day (5:30 to 19:40). During the nighttime, these parameters maintained about 200 lx, 2700 K, and 0.32, respectively. In this light environment, three subjects had engaged in shift work for 38 consecutive days. We measured plasma melatonin, activity counts, continuous performance tests, and visual analogue scale on mood to assess the rhythm, cognitive performance, and mood of subjects. After 38-day shift work, the subjects' peak melatonin concentration increased significantly. Their physiological and behavioral rhythms maintained stable. Their cognitive performance improved significantly after night work, compared with that before night work. Their mood status had no significant change during the 38-day shift work. These results indicated that the light environment was beneficial to maintain circadian rhythm, cognitive performance and mood status during long-term shift work in closed environment.
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Affiliation(s)
- Jingxin Nie
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
| | - Tianhang Zhou
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), Haidian District, 51, Huayuan North Road, Beijing, 100191, China
| | - Zhizhong Chen
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China.
| | - Weimin Dang
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), Haidian District, 51, Huayuan North Road, Beijing, 100191, China.
| | - Fei Jiao
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
| | - Jinglin Zhan
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
| | - Yifan Chen
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
| | - Yiyong Chen
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
| | - Zuojian Pan
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
| | - Xiangning Kang
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
| | - Yongzhi Wang
- Dongguan Institute of Optoelectronics, Peking University, Dongguan, 523808, Guangdong, China
| | - Qi Wang
- Dongguan Institute of Optoelectronics, Peking University, Dongguan, 523808, Guangdong, China
| | - Yan Tang
- Department of Physical Education, Peking University, Beijing, 100871, China
| | - Wentian Dong
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), Haidian District, 51, Huayuan North Road, Beijing, 100191, China
| | - Shuzhe Zhou
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), Haidian District, 51, Huayuan North Road, Beijing, 100191, China
| | - Yantao Ma
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), Haidian District, 51, Huayuan North Road, Beijing, 100191, China
| | - Xin Yu
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), Haidian District, 51, Huayuan North Road, Beijing, 100191, China
| | - Guoyi Zhang
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
- Dongguan Institute of Optoelectronics, Peking University, Dongguan, 523808, Guangdong, China
| | - Bo Shen
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, 209, Chengfu Road, Haidian District, Beijing, 100871, China
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15
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Reiter RJ, Sharma R, Rodriguez C, Martin V, Rosales-Corral S, Zuccari DAPDC, Chuffa LGDA. Part-time cancers and role of melatonin in determining their metabolic phenotype. Life Sci 2021; 278:119597. [PMID: 33974932 DOI: 10.1016/j.lfs.2021.119597] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/26/2021] [Accepted: 05/03/2021] [Indexed: 12/14/2022]
Abstract
This brief review describes the association of the endogenous pineal melatonin rhythm with the metabolic flux of solid tumors, particularly breast cancer. It also summarizes new information on the potential mechanisms by which endogenously-produced or exogenously-administered melatonin impacts the metabolic phenotype of cancer cells. The evidence indicates that solid tumors may redirect their metabolic phenotype from the pathological Warburg-type metabolism during the day to the healthier mitochondrial oxidative phosphorylation on a nightly basis. Thus, they function as cancer cells only during the day and as healthier cells at night, that is, they are only part-time cancerous. This switch to oxidative phosphorylation at night causes cancer cells to exhibit a reduced tumor phenotype and less likely to rapidly proliferate or to become invasive or metastatic. Also discussed is the likelihood that some solid tumors are especially aggressive during the day and much less so at night due to the nocturnal rise in melatonin which determines their metabolic state. We further propose that when melatonin is used/tested in clinical trials, a specific treatment paradigm be used that is consistent with the temporal metabolic changes in tumor metabolism. Finally, it seems likely that the concurrent use of melatonin in combination with conventional chemotherapies also would improve cancer treatment outcomes.
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Affiliation(s)
- Russel J Reiter
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.
| | - Ramaswamy Sharma
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA
| | - Carmen Rodriguez
- Departamento de Morfologia y Biologia Celular, Facultad de Medicina, Oviedo, 33006, Spain
| | - Vanesa Martin
- Departamento de Morfologia y Biologia Celular, Facultad de Medicina, Oviedo, 33006, Spain
| | - Sergio Rosales-Corral
- Centro de Investigacion Biomedica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara CP 45150, Mexico
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16
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Kompier ME, Smolders KCHJ, de Kort YAW. Abrupt light transitions in illuminance and correlated colour temperature result in different temporal dynamics and interindividual variability for sensation, comfort and alertness. PLoS One 2021; 16:e0243259. [PMID: 33750954 PMCID: PMC7984641 DOI: 10.1371/journal.pone.0243259] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 03/08/2021] [Indexed: 11/19/2022] Open
Abstract
Detailed insights in both visual effects of light and effects beyond vision due to manipulations in illuminance and correlated color temperature (CCT) are needed to optimize study protocols as well as to design light scenarios for practical applications. This study investigated temporal dynamics and interindividual variability in subjective evaluations of sensation, comfort and mood as well as subjective and objective measures of alertness, arousal and thermoregulation following abrupt transitions in illuminance and CCT in a mild cold environment. The results revealed that effects could be uniquely attributed to changes in illuminance or CCT. No interaction effects of illuminance and CCT were found for any of these markers. Responses to the abrupt transitions in illuminance and CCT always occurred immediately and exclusively amongst the subjective measures. Most of these responses diminished over time within the 45-minute light manipulation. In this period, no responses were found for objective measures of vigilance, arousal or thermoregulation. Significant interindividual variability occurred only in the visual comfort evaluation in response to changes in the intensity of the light. The results indicate that the design of dynamic light scenarios aimed to enhance human alertness and vitality requires tailoring to the individual to create visually comfortable environments.
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Affiliation(s)
- Maaike E. Kompier
- Human-Technology Interaction, School of Innovation Sciences, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Karin C. H. J. Smolders
- Human-Technology Interaction, School of Innovation Sciences, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Yvonne A. W. de Kort
- Human-Technology Interaction, School of Innovation Sciences, Eindhoven University of Technology, Eindhoven, the Netherlands
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17
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Walbeek TJ, Harrison EM, Gorman MR, Glickman GL. Naturalistic Intensities of Light at Night: A Review of the Potent Effects of Very Dim Light on Circadian Responses and Considerations for Translational Research. Front Neurol 2021; 12:625334. [PMID: 33597916 PMCID: PMC7882611 DOI: 10.3389/fneur.2021.625334] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 01/06/2021] [Indexed: 12/16/2022] Open
Abstract
In this review, we discuss the remarkable potency and potential applications of a form of light that is often overlooked in a circadian context: naturalistic levels of dim light at night (nLAN), equivalent to intensities produced by the moon and stars. It is often assumed that such low levels of light do not produce circadian responses typically associated with brighter light levels. A solid understanding of the impacts of very low light levels is complicated further by the broad use of the somewhat ambiguous term “dim light,” which has been used to describe light levels ranging seven orders of magnitude. Here, we lay out the argument that nLAN exerts potent circadian effects on numerous mammalian species, and that given conservation of anatomy and function, the efficacy of light in this range in humans warrants further investigation. We also provide recommendations for the field of chronobiological research, including minimum requirements for the measurement and reporting of light, standardization of terminology (specifically as it pertains to “dim” light), and ideas for reconsidering old data and designing new studies.
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Affiliation(s)
- Thijs J Walbeek
- Center for Circadian Biology, University of California, San Diego, La Jolla, CA, United States.,Oregon Institute of Occupational Health Sciences, Oregon Health and Science University, Portland, OR, United States
| | - Elizabeth M Harrison
- Center for Circadian Biology, University of California, San Diego, La Jolla, CA, United States
| | - Michael R Gorman
- Center for Circadian Biology, University of California, San Diego, La Jolla, CA, United States.,Department of Psychology, University of California, San Diego, San Diego, CA, United States
| | - Gena L Glickman
- Center for Circadian Biology, University of California, San Diego, La Jolla, CA, United States.,Departments of Psychiatry and Neuroscience, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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18
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Touitou Y, Point S. Effects and mechanisms of action of light-emitting diodes on the human retina and internal clock. ENVIRONMENTAL RESEARCH 2020; 190:109942. [PMID: 32758719 DOI: 10.1016/j.envres.2020.109942] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/29/2020] [Accepted: 07/10/2020] [Indexed: 05/11/2023]
Abstract
White light-emitting diodes (LEDs) will likely become the most used lighting devices worldwide in the future because of their very low prices over the course of their long lifespans which can be up to several tens of thousands of hours. The expansion of LED use in both urban and domestic lighting has prompted questions regarding their possible health effects, because the light that they provide is potentially high in the harmful blue band (400-500 nm) of the visible light spectrum. Research on the potential effects of LEDs and their blue band on human health has followed three main directions: 1) examining their retinal phototoxicity; 2) examining disruption of the internal clock, i.e., an out-of-sync clock, in shift workers and night workers, including the accompanying health issues, most concerningly an increased relative risk of cancer; and 3) examining risky, inappropriate late-night use of smartphones and consoles among children and adolescents. Here, we document the recognized or potential health issues associated with LED lighting together with their underlying mechanisms of action. There is so far no evidence that LED lighting is deleterious to human retina under normal use. However, exposure to artificial light at night is a new source of pollution because it affects the circadian clock. Blue-rich light, including cold white LEDs, should be considered a new endocrine disruptor, because it affects estrogen secretion and has unhealthful consequences in women, as demonstrated to occur via a complex mechanism.
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Affiliation(s)
- Yvan Touitou
- Unité de Chronobiologie, Fondation A. de Rothschild, 75019, Paris, France.
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19
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Sunde E, Pedersen T, Mrdalj J, Thun E, Grønli J, Harris A, Bjorvatn B, Waage S, Skene DJ, Pallesen S. Blue-Enriched White Light Improves Performance but Not Subjective Alertness and Circadian Adaptation During Three Consecutive Simulated Night Shifts. Front Psychol 2020; 11:2172. [PMID: 33013558 PMCID: PMC7462016 DOI: 10.3389/fpsyg.2020.02172] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 08/03/2020] [Indexed: 01/28/2023] Open
Abstract
Use of blue-enriched light has received increasing interest regarding its activating and performance sustaining effects. However, studies assessing effects of such light during night work are few, and novel strategies for lighting using light emitting diode (LED) technology need to be researched. In a counterbalanced crossover design, we investigated the effects of a standard polychromatic blue-enriched white light (7000 K; ∼200 lx) compared to a warm white light (2500 K), of similar photon density (∼1.6 × 1014 photons/cm2/s), during three consecutive simulated night shifts. A total of 30 healthy participants [10 males, mean age 23.3 (SD = 2.9) years] were included in the study. Dependent variables comprised subjective alertness using the Karolinska Sleepiness Scale, a psychomotor vigilance task (PVT) and a digit symbol substitution test (DSST), all administered at five time points throughout each night shift. We also assessed dim-light melatonin onset (DLMO) before and after the night shifts, as well as participants' opinion of the light conditions. Subjective alertness and performance on the PVT and DSST deteriorated during the night shifts, but 7000 K light was more beneficial for performance, mainly in terms of fewer errors on the PVT, at the end of the first- and second- night shift, compared to 2500 K light. Blue-enriched light only had a minor impact on PVT response times (RTs), as only the fastest 10% of the RTs were significantly improved in 7000 K compared to 2500 K light. In both 7000 and 2500 K light, the DLMO was delayed in those participants with valid assessment of this parameter [n = 20 (69.0%) in 7000 K light, n = 22 (78.6%) in 2500 K light], with a mean of 2:34 (SE = 0:14) and 2:12 (SE = 0:14) hours, respectively, which was not significantly different between the light conditions. Both light conditions were positively rated, although participants found 7000 K to be more suitable for work yet evaluated 2500 K light as more pleasant. The data indicate minor, but beneficial, effects of 7000 K light compared to 2500 K light on performance during night work. Circadian adaptation did not differ significantly between light conditions, though caution should be taken when interpreting these findings due to missing data. Field studies are needed to investigate similar light interventions in real-life settings, to develop recommendations regarding illumination for night workers. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03203538.
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Affiliation(s)
- Erlend Sunde
- Department of Psychosocial Science, University of Bergen, Bergen, Norway
| | - Torhild Pedersen
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
| | - Jelena Mrdalj
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
| | - Eirunn Thun
- Department of Clinical Psychology, University of Bergen, Bergen, Norway
| | - Janne Grønli
- Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway
| | - Anette Harris
- Department of Psychosocial Science, University of Bergen, Bergen, Norway
| | - Bjørn Bjorvatn
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
- Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway
| | - Siri Waage
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
- Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway
| | - Debra J Skene
- Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Ståle Pallesen
- Department of Psychosocial Science, University of Bergen, Bergen, Norway
- Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway
- Optentia, North-West University Vaal Triangle Campus, Vanderbijlpark, South Africa
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20
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Brown TM. Melanopic illuminance defines the magnitude of human circadian light responses under a wide range of conditions. J Pineal Res 2020; 69:e12655. [PMID: 32248548 DOI: 10.1111/jpi.12655] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 02/28/2020] [Accepted: 03/27/2020] [Indexed: 12/18/2022]
Abstract
Ocular light drives a range of nonvisual responses in humans including suppression of melatonin secretion and circadian phase resetting. These responses are driven by intrinsically photosensitive retinal ganglion cells (ipRGCs) which combine intrinsic, melanopsin-based, phototransduction with extrinsic rod/cone-mediated signals. As a result of this arrangement, it has remained unclear how best to quantify light to predict its nonvisual effects. To address this, we analysed data from nineteen different laboratory studies that measured melatonin suppression, circadian phase resetting and/or alerting responses in humans to a wide array of stimulus types, intensities and durations with or without pupil dilation. Using newly established SI-compliant metrics to quantify ipRGC-influenced responses to light, we show that melanopic illuminance consistently provides the best available predictor for responses of the human circadian system. In almost all cases, melanopic illuminance is able to fully account for differences in sensitivity to stimuli of varying spectral composition, acting to drive responses that track variations in illumination characteristic of those encountered over civil twilight (~1-1000 lux melanopic equivalent daylight illuminance). Collectively, our data demonstrate widespread utility of melanopic illuminance as a metric for predicting the circadian impact of environmental illumination. These data therefore provide strong support for the use of melanopic illuminance as the basis for guidelines that seek to regulate light exposure to benefit human health and to inform future lighting design.
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Affiliation(s)
- Timothy M Brown
- Centre for Biological Timing, Faculty of Medicine, Biology and Health, University of Manchester, Manchester, UK
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21
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Hanifin JP, Dauchy RT, Blask DE, Hill SM, Brainard GC. Relevance of Electrical Light on Circadian, Neuroendocrine, and Neurobehavioral Regulation in Laboratory Animal Facilities. ILAR J 2020; 60:150-158. [PMID: 33094817 DOI: 10.1093/ilar/ilaa010] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 03/25/2020] [Accepted: 04/15/2020] [Indexed: 02/03/2023] Open
Abstract
Light is a key extrinsic factor to be considered in operations and design of animal room facilities. Over the past four decades, many studies on typical laboratory animal populations have demonstrated impacts on neuroendocrine, neurobehavioral, and circadian physiology. These effects are regulated independently from the defined physiology for the visual system. The range of physiological responses that oscillate with the 24 hour rhythm of the day include sleep and wakefulness, body temperature, hormonal secretion, and a wide range of other physiological parameters. Melatonin has been the chief neuroendocrine hormone studied, but acute light-induced effects on corticosterone as well as other hormones have also been observed. Within the last two decades, a new photosensory system in the mammalian eye has been discovered. A small set of retinal ganglion cells, previously thought to function as a visual output neuron, have been shown to be directly photosensitive and act differently from the classic photoreceptors of the visual system. Understanding the effects of light on mammalian physiology and behavior must take into account how the classical visual photoreceptors and the newly discovered ipRGC photoreceptor systems interact. Scientists and facility managers need to appreciate lighting impacts on circadian, neuroendocrine, and neurobehavioral regulation in order to improve lighting of laboratory facilities to foster optimum health and well-being of animals.
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Affiliation(s)
- John P Hanifin
- Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Robert T Dauchy
- Department of Structural and Cellular Biology, Tulane University School of Medicine, Tulane, Louisiana
| | - David E Blask
- Department of Structural and Cellular Biology, Tulane University School of Medicine, Tulane, Louisiana
| | - Steven M Hill
- Department of Structural and Cellular Biology, Tulane University School of Medicine, Tulane, Louisiana
| | - George C Brainard
- Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania
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22
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Seo JA, Lee DY, Yu JH, Cho H, Lee SK, Suh S, Kim SG, Choi KM, Baik SH, Shin C, Kim NH. Habitual late sleep initiation is associated with increased incidence of type 2 diabetes mellitus in Korean adults: the Korean Genome and Epidemiology Study. Sleep 2020; 42:5473601. [PMID: 30994171 DOI: 10.1093/sleep/zsz090] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 03/04/2019] [Indexed: 12/21/2022] Open
Abstract
STUDY OBJECTIVES Although sleep duration and quality were significant risk factors of type 2 diabetes (T2D), the impact of sleep initiation time on the development of T2D has not been studied in large longitudinal studies. METHODS A total of 3689 participants without diabetes aged 40-69 years at baseline were enrolled from the Korean Genome and Epidemiology Study and followed up for 12 years. Participants were categorized based on habitual sleep initiation time by questionnaire as follows: 20:00-22:59 (early sleepers, ES, n = 766), 23:00-00:59 (usual sleepers, US, n = 2407), and 1:00-5:59 (late sleepers, LS, n = 516). Incident T2D was identified biennially by fasting plasma glucose or 2-hour glucose after 75-g oral glucose loading or use of anti-diabetes medication. RESULTS During follow-up, 820 cases of T2D were documented and the LS group showed the highest increase in insulin resistance. Hazard ratio (HR) (95% confidence interval) for T2D of LS compared to ES was 1.34 (1.04-1.74) after adjustment for covariates including sleep duration. The impact of late sleep on the development of T2D was more evident in older individuals (≥65 years at baseline) (HR = 4.24 [1.42-12.68] in older LS vs. older ES, HR = 1.27 [1.00-1.62] in younger LS vs. younger ES, pinteraction = 0.002). In addition, LS with low insulin secretion and sensitivity showed an approximately fivefold increased risk for T2D compared to ES with high insulin secretion and sensitivity. CONCLUSIONS/INTERPRETATION Habitual late sleep initiation is a significant risk factor for T2D in Koreans, especially in people with lower insulin sensitivity, lower β-cell function, and older age.
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Affiliation(s)
- Ji A Seo
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Da Young Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Ji Hee Yu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Hyunjoo Cho
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Seung Ku Lee
- Institute of Human Genomic Study, Korea University Ansan Hospital, Ansan, Korea
| | - Sooyeon Suh
- Department of Psychology, Sungshin Women's University, Seoul, Korea
| | - Sin Gon Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Kyung Mook Choi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Sei Hyun Baik
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Chol Shin
- Institute of Human Genomic Study, Korea University Ansan Hospital, Ansan, Korea.,Division of Respiratory and Critical Care Medicine, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
| | - Nan Hee Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
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Effects of Different Light Sources on Neural Activity of the Paraventricular Nucleus in the Hypothalamus. ACTA ACUST UNITED AC 2019; 55:medicina55110732. [PMID: 31717519 PMCID: PMC6915334 DOI: 10.3390/medicina55110732] [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: 09/30/2019] [Revised: 10/30/2019] [Accepted: 11/06/2019] [Indexed: 12/03/2022]
Abstract
Background and Objectives: Physical function is influenced by light irradiation, and interest in the influence of light irradiation on health is high. Light signals are transmitted from the retina to the suprachiasmatic nucleus (SCN) via the retinal hypothalamic tract as non-image vision. Additionally, the SCN projects a nerve to the paraventricular nucleus (PVN) which acts as a stress center. This study examined the influences of three different light sources on neural activity in the PVN region using two different color temperatures. Materials and Methods: Experiments were conducted using twenty-eight Institute of Cancer Research (ICR) mice (10 week old males). Three light sources were used: (1) organic light-emitting diode (OLED) lighting, (2) LED lighting, and (3) fluorescent lighting. We examined the effects of light irradiation from the three light sources using two different color temperatures (2800 K and 4000 K). Perfusion was done 60 min after light irradiation, and then the brain was removed from the mouse for an immunohistochemistry analysis. c-Fos was immunohistochemically visualized as a marker of neural activity in the PVN region. Results: The number of c-Fos-positive cells was found to be significantly lower under OLED lighting and LED lighting conditions than under fluorescent lighting at a color temperature of 2800 K, and significantly lower under OLED lighting than LED lighting conditions at a color temperature of 4000 K. Conclusions: This study reveals that different light sources and color temperatures alter the neural activity of the PVN region. These results suggest that differences in the light source or color temperature may affect the stress response.
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High sensitivity and interindividual variability in the response of the human circadian system to evening light. Proc Natl Acad Sci U S A 2019; 116:12019-12024. [PMID: 31138694 PMCID: PMC6575863 DOI: 10.1073/pnas.1901824116] [Citation(s) in RCA: 202] [Impact Index Per Article: 40.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Electric lighting has fundamentally altered how the human circadian clock synchronizes to the day/night cycle. Exposure to light after dusk is pervasive in the modern world. We examined group-level sensitivity of the circadian system to evening light and the degree to which sensitivity varies between individuals. We found that, on average, humans are highly sensitive to evening light. Specifically, 50% suppression of melatonin occurred at <30 lux, which is comparable to or lower than typical indoor lighting used at night, as well as light produced by electronic devices. Significantly, there was a >50-fold difference in sensitivity to evening light across individuals. Interindividual differences in light sensitivity may explain differential vulnerability to circadian disruption and subsequent impact on human health. Before the invention of electric lighting, humans were primarily exposed to intense (>300 lux) or dim (<30 lux) environmental light—stimuli at extreme ends of the circadian system’s dose–response curve to light. Today, humans spend hours per day exposed to intermediate light intensities (30–300 lux), particularly in the evening. Interindividual differences in sensitivity to evening light in this intensity range could therefore represent a source of vulnerability to circadian disruption by modern lighting. We characterized individual-level dose–response curves to light-induced melatonin suppression using a within-subjects protocol. Fifty-five participants (aged 18–30) were exposed to a dim control (<1 lux) and a range of experimental light levels (10–2,000 lux for 5 h) in the evening. Melatonin suppression was determined for each light level, and the effective dose for 50% suppression (ED50) was computed at individual and group levels. The group-level fitted ED50 was 24.60 lux, indicating that the circadian system is highly sensitive to evening light at typical indoor levels. Light intensities of 10, 30, and 50 lux resulted in later apparent melatonin onsets by 22, 77, and 109 min, respectively. Individual-level ED50 values ranged by over an order of magnitude (6 lux in the most sensitive individual, 350 lux in the least sensitive individual), with a 26% coefficient of variation. These findings demonstrate that the same evening-light environment is registered by the circadian system very differently between individuals. This interindividual variability may be an important factor for determining the circadian clock’s role in human health and disease.
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25
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de Oliveira MAB, Scop M, Abreu ACO, Sanches PRS, Rossi AC, Díez-Noguera A, Calcagnotto ME, Hidalgo MP. Entraining effects of variations in light spectral composition on the rest-activity rhythm of a nocturnal rodent. Chronobiol Int 2019; 36:934-944. [DOI: 10.1080/07420528.2019.1599008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Melissa A. B. de Oliveira
- Laboratório de Cronobiologia e Sono (BRAIN), Hospital de Clínicas de Porto Alegre (HCPA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Programa de Pós-graduação em Psiquiatria e Ciências do Comportamento, Faculdade de Medicina, UFRGS, Porto Alegre, Brazil
| | - Marina Scop
- Laboratório de Cronobiologia e Sono (BRAIN), Hospital de Clínicas de Porto Alegre (HCPA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Ana Carolina Odebrecht Abreu
- Laboratório de Cronobiologia e Sono (BRAIN), Hospital de Clínicas de Porto Alegre (HCPA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | | | - Augusto Camargo Rossi
- Biomedical Engineering Department, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil
| | - Antoni Díez-Noguera
- Department de Bioquimica i Fisiologia, Facultat de Farmàcia i Ciències de l’Alimentació, Universitat de Barcelona, Barcelona, Spain
| | - Maria Elisa Calcagnotto
- Programa de Pós-graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, UFRGS, Porto Alegre, Brazil
- Programa de Pós-graduação em Neurociências, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Brazil
- Laboratório de Neurofisiologia e Neuroquímica da Excitabilidade Neuronal e Plasticidade Sináptica, Departamento de Bioquímica, UFRGS, Porto Alegre, Brazil
| | - Maria Paz Hidalgo
- Laboratório de Cronobiologia e Sono (BRAIN), Hospital de Clínicas de Porto Alegre (HCPA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Programa de Pós-graduação em Psiquiatria e Ciências do Comportamento, Faculdade de Medicina, UFRGS, Porto Alegre, Brazil
- Departamento de Psiquiatria e Medicina Legal, Faculdade de Medicina, UFRGS, Porto Alegre, Brazil
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Rodrigues R, de Azevedo Franke R, Teixeira BC, Cauduro Oliveira Macedo R, Diefenthaeler F, Baroni BM, Vaz MA. Can the Combination of Acute Alcohol Intake and One Night of Sleep Deprivation Affect Neuromuscular Performance in Healthy Male Adults? A Cross-over Randomized Controlled Trial. J Strength Cond Res 2019; 33:1244-1251. [PMID: 30908373 DOI: 10.1519/jsc.0000000000003124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rodrigues, R, Franke, RA, Teixeira, BC, Macedo, RCO, Diefenthaeler, F, Baroni, BM, and Vaz, MA. Can the combination of acute alcohol intake and one night of sleep deprivation affect neuromuscular performance in healthy male adults? A cross-over randomized controlled trial. J Strength Cond Res 33(5): 1244-1251, 2019-The aim of this work was to perform a cross-over study to compare isolated and combined effects of alcohol intake and sleep deprivation on neuromuscular responses. Ten young and physically active male subjects were allocated to 4 conditions: (a) placebo intake + normal sleep (PLA + SLE); (b) alcohol intake + normal sleep (ALC + SLE); (c) placebo intake + sleep deprivation (PLA + SDP); and (d) alcohol intake + sleep deprivation (ALC + SDP). In each condition, volunteers ingested 1 g of alcohol per kg of body mass of alcoholic beer or nonalcoholic beer (placebo), followed by one night of normal sleep or sleep deprivation. In the next morning, neuromuscular performance (knee extensor isometric and concentric peak torque and time to task failure during the endurance test) and muscle activation were assessed. No differences were observed in the neuromuscular performance. We observed a significant reduction in quadriceps activation during the knee extensor isometric test in ALC + SDP compared with PLA + SLE (-20.8%; p = 0.02; d = 0.56). Our results demonstrated that acute alcohol intake and one night of sleep deprivation reduced quadriceps muscle activation without impact on neuromuscular performance.
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Affiliation(s)
- Rodrigo Rodrigues
- Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.,University Center of Serra Gaúcha, Caxias do Sul, RS, Brazil
| | | | | | | | | | - Bruno M Baroni
- Federal University of Saúde de Porto Alegre, Porto Alegre, RS, Brazil
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