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Author Wang, H.-B.; Whittaker, D.S.; Truong, D.; Mulji, A.K.; Ghiani, C.A.; Loh, D.H.; Colwell, C.S.
Title Blue light therapy improves circadian dysfunction as well as motor symptoms in two mouse models of Huntington's disease Type Journal Article
Year 2017 Publication Neurobiology of Sleep and Circadian Rhythms Abbreviated Journal Neurobiology of Sleep and Circadian Rhythms
Volume (down) 2 Issue Pages 39-52
Keywords animals; Human Health
Abstract Patients with Huntington's disease (HD) exhibit movement disorders, psychiatric disturbance and cognitive impairments as the disease progresses. Abnormal sleep/wake cycles are common among HD patients with reports of delayed sleep onset, fatigue during the day, and a delayed pattern of melatonin secretion all of which suggest circadian dysfunction. Mouse models of HD confirm disrupted circadian rhythms with pathophysiology found in the central circadian clock (suprachiasmatic nucleus). Importantly, circadian dysfunction manifests early in disease, even before the classic motor symptoms, in both patients and mouse models. Therefore, we hypothesize that the circadian dysfunction may interact with the disease pathology and exacerbate the HD symptoms. If correct, early intervention may benefit patients and delay disease progression. One test of this hypothesis is to determine whether light therapy designed to strengthen this intrinsic timing system can delay the disease progression in mouse models. Therefore, we determined the impact of blue wavelength-enriched light on two HD models: the BACHD and Q175 mice. Both models received 6 hours of blue-light at the beginning of their daily light cycle for 3 months. After treatment, both genotypes showed improvements in their locomotor activity rhythm without significant change to their sleep behavior. Critically, treated mice of both lines exhibited improved motor performance compared to untreated controls. Focusing on the Q175 genotype, we sought to determine whether the treatment altered signaling pathways in brain regions known to be impacted by HD using NanoString gene expression assays. We found that the expression of several HD relevant markers was altered in the striatum and cortex of the treated mice. Our study demonstrates that strengthening the circadian system can delay the progression of HD in pre-clinical models. This work suggests that lighting conditions should be considered when managing treatment of HD and other neurodegenerative disorders.
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Series Volume Series Issue Edition
ISSN 2451-9944 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kyba @ Serial 1626
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Author Aarts, M.P.J.; Hartmeyer, S.L.; Morsink, K.; Kort, H.S.M.; de Kort, Y.A.W.
Title Can Special Light Glasses Reduce Sleepiness and Improve Sleep of Nightshift Workers? A Placebo-Controlled Explorative Field Study Type Journal Article
Year 2020 Publication Clocks & Sleep Abbreviated Journal Clocks & Sleep
Volume (down) 2 Issue 2 Pages 225-245
Keywords Human Health
Abstract Nightshift workers go against the natural sleep–wake rhythm. Light can shift the circadian clock but can also induce acute alertness. This placebo-controlled exploratory field study examined the effectiveness of light glasses to improve alertness while reducing the sleep complaints of hospital nurses working nightshifts. In a crossover within-subjects design, 23 nurses participated, using treatment glasses and placebo glasses. Sleepiness and sleep parameters were measured. A linear mixed model analysis on sleepiness revealed no significant main effect of the light intervention. An interaction effect was found indicating that under the placebo condition, sleepiness was significantly higher on the first nightshift than on the last night, while under the treatment condition, sleepiness remained stable across nightshift sessions. Sleepiness during the commute home also showed a significant interaction effect, demonstrating that after the first nightshift, driver sleepiness was higher for placebo than for treatment. Subjective sleep quality showed a negative main effect of treatment vs. placebo, particularly after the first nightshift. In retrospect, both types of light glasses were self-rated as effective. The use of light glasses during the nightshift may help to reduce driver sleepiness during the commute home, which is relevant, as all participants drove home by car or (motor) bike.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2624-5175 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2977
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Author Panagiotou, M.; Rohling, J.H.T.; Deboer, T.
Title Sleep Network Deterioration as a Function of Dim-Light-At-Night Exposure Duration in a Mouse Model Type Journal Article
Year 2020 Publication Clocks & Sleep Abbreviated Journal Clocks & Sleep
Volume (down) 2 Issue 3 Pages 308-324
Keywords Animals
Abstract Artificial light, despite its widespread and valuable use, has been associated withdeterioration of health and well-being, including altered circadian timing and sleep disturbances,particularly in nocturnal exposure. Recent findings from our lab reveal significant sleep andsleep electroencephalogram (EEG) changes owing to three months exposure to dim-light-at-night(DLAN). Aiming to further explore the detrimental effects of DLAN exposure, in the present study,we continuously recorded sleep EEG and the electromyogram for baseline 24-h and following 6-h sleepdeprivation in a varied DLAN duration scheme. C57BL/6J mice were exposed to a 12:12 h light:DLANcycle (75lux:5lux) vs. a 12:12 h light:dark cycle (75lux:0lux) for one day, one week, and one month.Our results show that sleep was already affected by a mere day of DLAN exposure with additionalcomplications emerging with increasing DLAN exposure duration, such as the gradual delay ofthe daily 24-h vigilance state rhythms. We conducted detrended fluctuation analysis (DFA) on thelocomotor activity data following 1-month and 3-month DLAN exposure, and a significantly lesshealthy rest-activity pattern, based on the decreased alpha values, was found in both conditionscompared to the control light-dark. Taking into account the behavioral, sleep and the sleep EEGparameters, our data suggest that DLAN exposure, even in the shortest duration, induces deleteriouseffects; nevertheless, potential compensatory mechanisms render the organism partly adjustable andable to cope. We think that, for this reason, our data do not always depict linear divergence amonggroups, as compared with control conditions. Chronic DLAN exposure impacts the sleep regulatorysystem, but also brain integrity, diminishing its adaptability and reactivity, especially apparent in thesleep EEG alterations and particular low alpha values following DFA.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2624-5175 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 3078
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Author Juda, M.; Liu-Ambrose, T.; Feldman, F.; Suvagau, C.; Mistlberger, R.E.
Title Light in the Senior Home: Effects of Dynamic and Individual Light Exposure on Sleep, Cognition, and Well-Being Type Journal Article
Year 2020 Publication Clocks & Sleep Abbreviated Journal Clocks Sleep
Volume (down) 2 Issue 4 Pages 557-576
Keywords Human health; aging; circadian rhythms; cognition; entrainment; light; nursing home; sleep
Abstract Disrupted sleep is common among nursing home patients and is associated with cognitive decline and reduced well-being. Sleep disruptions may in part be a result of insufficient daytime light exposure. This pilot study examined the effects of dynamic “circadian” lighting and individual light exposure on sleep, cognitive performance, and well-being in a sample of 14 senior home residents. The study was conducted as a within-subject study design over five weeks of circadian lighting and five weeks of conventional lighting, in a counterbalanced order. Participants wore wrist accelerometers to track rest-activity and light profiles and completed cognitive batteries (National Institute of Health (NIH) toolbox) and questionnaires (depression, fatigue, sleep quality, lighting appraisal) in each condition. We found no significant differences in outcome variables between the two lighting conditions. Individual differences in overall (indoors and outdoors) light exposure levels varied greatly between participants but did not differ between lighting conditions, except at night (22:00-6:00), with maximum light exposure being greater in the conventional lighting condition. Pooled data from both conditions showed that participants with higher overall morning light exposure (6:00-12:00) had less fragmented and more stable rest-activity rhythms with higher relative amplitude. Rest-activity rhythm fragmentation and long sleep duration both uniquely predicted lower cognitive performance.
Address Sleep and Circadian Neuroscience Laboratory, Department of Psychology, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2624-5175 ISBN Medium
Area Expedition Conference
Notes PMID:33327499; PMCID:PMC7768397 Approved no
Call Number GFZ @ kyba @ Serial 3261
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Author Akacem, L.D.; Wright, K.P.J.; LeBourgeois, M.K.
Title Bedtime and evening light exposure influence circadian timing in preschool-age children: A field study Type Journal Article
Year 2016 Publication Neurobiology of Sleep and Circadian Rhythms Abbreviated Journal Neurobiol Sleep Circadian Rhythms
Volume (down) 1 Issue 2 Pages 27-31
Keywords Human Health
Abstract Light exposure and sleep timing are two factors that influence inter-individual variability in the timing of the human circadian clock. The aim of this study was to quantify the degree to which evening light exposure predicts variance in circadian timing over and above bedtime alone in preschool children. Participants were 21 children ages 4.5-5.0 years (4.7 +/- 0.2 years; 9 females). Children followed their typical sleep schedules for 4 days during which time they wore a wrist actigraph to assess sleep timing and a pendant light meter to measure minute-by-minute illuminance levels in lux. On the 5th day, children participated in an in-home dim-light melatonin onset (DLMO) assessment. Light exposure in the 2 h before bedtime was averaged and aggregated across the 4 nights preceding the DLMO assessment. Mean DLMO and bedtime were 19:22 +/- 01:04 and 20:07 +/- 00:46, respectively. Average evening light exposure was 710.1 +/- 1418.2 lux. Children with later bedtimes (lights-off time) had more delayed melatonin onset times (r=0.61, p=0.002). Evening light exposure was not independently associated with DLMO (r=0.32, p=0.08); however, a partial correlation between evening light exposure and DLMO when controlling for bedtime yielded a positive correlation (r=0.46, p=0.02). Bedtime explained 37.3% of the variance in the timing of DLMO, and evening light exposure accounted for an additional 13.3% of the variance. These findings represent an important step in understanding factors that influence circadian phase in preschool-age children and have implications for understanding a modifiable pathway that may underlie late sleep timing and the development of evening settling problems in early childhood.
Address Sleep and Development Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2451-9944 ISBN Medium
Area Expedition Conference
Notes PMID:28042611; PMCID:PMC5193478 Approved no
Call Number LoNNe @ kyba @ Serial 1755
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