|   | 
Details
   web
Records
Author Wams, E.J.; Woelders, T.; Marring, I.; van Rosmalen, L.; Beersma, D.G.M.; Gordijn, M.C.M.; Hut, R.A.
Title Linking Light Exposure and Subsequent Sleep: A Field Polysomnography Study in Humans Type (up) Journal Article
Year 2017 Publication Sleep Abbreviated Journal Sleep
Volume 40 Issue 12 Pages
Keywords actigraphy; chronobiology; circadian rhythms; scoring; sleep/wake mechanisms
Abstract Study objectives: To determine the effect of light exposure on subsequent sleep characteristics under ambulatory field conditions. Methods: Twenty healthy participants were fitted with ambulatory polysomnography (PSG) and wrist-actigraphs to assess light exposure, rest-activity, sleep quality, timing, and architecture. Laboratory salivary dim-light melatonin onset was analyzed to determine endogenous circadian phase. Results: Later circadian clock phase was associated with lower intensity (R2 = 0.34, chi2(1) = 7.19, p < .01), later light exposure (quadratic, controlling for daylength, R2 = 0.47, chi2(3) = 32.38, p < .0001), and to later sleep timing (R2 = 0.71, chi2(1) = 20.39, p < .0001). Those with later first exposure to more than 10 lux of light had more awakenings during subsequent sleep (controlled for daylength, R2 = 0.36, chi2(2) = 8.66, p < .05). Those with later light exposure subsequently had a shorter latency to first rapid eye movement (REM) sleep episode (R2 = 0.21, chi2(1) = 5.77, p < .05). Those with less light exposure subsequently had a higher percentage of REM sleep (R2 = 0.43, chi2(2) = 13.90, p < .001) in a clock phase modulated manner. Slow-wave sleep accumulation was observed to be larger after preceding exposure to high maximal intensity and early first light exposure (p < .05). Conclusions: The quality and architecture of sleep is associated with preceding light exposure. We propose that light exposure timing and intensity do not only modulate circadian-driven aspects of sleep but also homeostatic sleep pressure. These novel ambulatory PSG findings are the first to highlight the direct relationship between light and subsequent sleep, combining knowledge of homeostatic and circadian regulation of sleep by light. Upon confirmation by interventional studies, this hypothesis could change current understanding of sleep regulation and its relationship to prior light exposure. Clinical trial details: This study was not a clinical trial. The study was ethically approved and nationally registered (NL48468.042.14).
Address Chronobiology Unit, Groningen Institute for Evolutionary Life Sciences, University of Groningen, The Netherlands
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 0161-8105 ISBN Medium
Area Expedition Conference
Notes PMID:29040758; PMCID:PMC5806586 Approved no
Call Number GFZ @ kyba @ Serial 1885
Permanent link to this record
 

 
Author Phillips, A.J.K.; Vidafar, P.; Burns, A.C.; McGlashan, E.M.; Anderson, C.; Rajaratnam, S.M.W.; Lockley, S.W.; Cain, S.W.
Title High sensitivity and interindividual variability in the response of the human circadian system to evening light Type (up) Journal Article
Year 2019 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc Natl Acad Sci U S A
Volume 116 Issue 24 Pages 12019-12024
Keywords Human Health; circadian rhythms; light sensitivity; circadian disruption; melatonin suppression; evening light
Abstract 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.
Address Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Melbourne, Victoria, Australia sean.cain@monash.edu
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 0027-8424 ISBN Medium
Area Expedition Conference
Notes PMID:31138694 Approved no
Call Number IDA @ intern @ Serial 2521
Permanent link to this record
 

 
Author Blagonravov, M.L.; Bryk, A.A.; Medvedeva, E.V.; Goryachev, V.A.; Chibisov, S.M.; Kurlaeva, A.O.; Agafonov, E.D.
Title Structure of Rhythms of Blood Pressure, Heart Rate, Excretion of Electrolytes, and Secretion of Melatonin in Normotensive and Spontaneously Hypertensive Rats Maintained under Conditions of Prolonged Daylight Duration Type (up) Journal Article
Year 2019 Publication Bulletin of Experimental Biology and Medicine Abbreviated Journal Bull Exp Biol Med
Volume 168 Issue 1 Pages 18-23
Keywords Animals; arterial hypertension; biological rhythms; excessive exposure to light; melatonin
Abstract We studied the structure of rhythms of BP, HR (by telemetric monitoring), electrolyte excretion (by capillary electrophoresis), and products of epiphyseal melatonin (by the urinary concentration of 6-sulfatoxymelatonin measured by ELISA) in normotensive Wistar-Kyoto rats and spontaneously hypertensive SHR rats maintained at 16/8 h and 20/4 h light-dark regimes. In Wister-Kyoto rats exposed to prolonged daylight, we observed changes in the amplitude, rhythm power (% of rhythm), and range of oscillations of systolic BP; HR mezor decreased. In SHR rats, mezor of HR also decreased, but other parameters of rhythms remained unchanged. Changes in electrolyte excretion were opposite in normo- and hypertensive rats. Under conditions of 20/4 h light-dark regime, daytime melatonin production tended to increase in normotensive rats and significantly increased in SHR rats. At the same time, nighttime melatonin production did not change in both normotensive and hypertensive animals. As the secretion of melatonin has similar features in animals of both lines, we can say that the epiphyseal component of the “biological clock” is not the only component of the functional system that determines the response of the studied rhythms to an increase in the duration of light exposure.
Address V. A. Frolov Department of General Pathology and Pathophysiology, Institute for Medicine, Peoples' Friendship University of Russia, Moscow, Russia
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 0007-4888 ISBN Medium
Area Expedition Conference
Notes PMID:31741240 Approved no
Call Number GFZ @ kyba @ Serial 2755
Permanent link to this record
 

 
Author Andreatta, G.; Tessmar-Raible, K.
Title The still dark side of the moon: molecular mechanisms of lunar-controlled rhythms and clocks Type (up) Journal Article
Year 2020 Publication Journal of Molecular Biology Abbreviated Journal J Mol Biol
Volume in press Issue Pages
Keywords Review; Animals; Hormones; Lunar rhythms; Physiology; Proteome; Transcriptome
Abstract Starting with the beginning of the last century, a multitude of scientific studies has documented that the lunar cycle times behaviors and physiology in many organisms. It is plausible that even the first life forms adapted to the different rhythms controlled by the moon. Consistently, many marine species exhibit lunar rhythms, and also the number of documented “lunar-rhythmic” terrestrial species is increasing. Organisms follow diverse lunar geophysical/astronomical rhythms, which differ significantly in terms of period length: from hours (circalunidian and circatidal rhythms) to days (circasemilunar and circalunar cycles). Evidence for internal circatital and circalunar oscillators exists for a range of species based on past behavioral studies, but those species with well-documented behaviorally free-running lunar rhythms are not typically used for molecular studies. Thus, the underlying molecular mechanisms are largely obscure: the dark side of the moon. Here we review findings which start to connect molecular pathways with moon-controlled physiology and behaviors. The present data indicate connections between metabolic/endocrine pathways and moon-controlled rhythms, as well as interactions between circadian and circatidal/circalunar rhythms. Moreover, recent high-throughput analyses provide useful leads towards pathways, as well as molecular markers. However, for each interpretation it is important to carefully consider the – partly substantially differing – conditions used in each experimental paradigm. In the future, it will be important to use lab experiments to delineate the specific mechanisms of the different solar- and lunar-controlled rhythms, but to also start integrating them together, as life has evolved equally long under rhythms of both sun and moon.
Address Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna; Research Platform “Rhythms of Life”, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna. Electronic address: kristin.tessmar@mfpl.ac.at
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 0022-2836 ISBN Medium
Area Expedition Conference
Notes PMID:32198116 Approved no
Call Number GFZ @ kyba @ Serial 2865
Permanent link to this record