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Author (up) Chellappa, S.L.; Viola, A.U.; Schmidt, C.; Bachmann, V.; Gabel, V.; Maire, M.; Reichert, C.F.; Valomon, A.; Gotz, T.; Landolt, H.-P.; Cajochen, C.
Title Human melatonin and alerting response to blue-enriched light depend on a polymorphism in the clock gene PER3 Type Journal Article
Year 2012 Publication The Journal of Clinical Endocrinology and Metabolism Abbreviated Journal J Clin Endocrinol Metab
Volume 97 Issue 3 Pages E433-7
Keywords Adult; Alleles; Cross-Over Studies; Female; Genotype; Homozygote; Humans; *Light; Male; Melatonin/*blood/genetics; *Minisatellite Repeats; Period Circadian Proteins/*genetics; *Polymorphism, Genetic; Questionnaires; Sleep/genetics; Wakefulness/*genetics
Abstract CONTEXT: Light exposure, particularly at the short-wavelength range, triggers several nonvisual responses in humans. However, the extent to which the melatonin-suppressing and alerting effect of light differs among individuals remains unknown. OBJECTIVE: Here we investigated whether blue-enriched polychromatic light impacts differentially on melatonin and subjective and objective alertness in healthy participants genotyped for the PERIOD3 (PER3) variable-number, tandem-repeat polymorphism. DESIGN, SETTING, AND PARTICIPANTS: Eighteen healthy young men homozygous for the PER3 polymorphism (PER3(5/5)and PER3(4/4)) underwent a balanced crossover design during the winter season, with light exposure to compact fluorescent lamps of 40 lux at 6500 K and at 2500 K during 2 h in the evening. RESULTS: In comparison to light at 2500 K, blue-enriched light at 6500 K induced a significant suppression of the evening rise in endogenous melatonin levels in PER3(5/5) individuals but not in PER3(4/4). Likewise, PER3(5/5) individuals exhibited a more pronounced alerting response to light at 6500 K than PER3(4/4) volunteers. Waking electroencephalographic activity in the theta range (5-7 Hz), a putative correlate of sleepiness, was drastically attenuated during light exposure at 6500 K in PER3(5/5) individuals as compared with PER3(4/4). CONCLUSIONS: We provide first evidence that humans homozygous for the PER3 5/5 allele are particularly sensitive to blue-enriched light, as indexed by the suppression of endogenous melatonin and waking theta activity. Light sensitivity in humans may be modulated by a clock gene polymorphism implicated in the sleep-wake regulation.
Address Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Wilhelm Kleinstrasse 27, CH-4012 Basel, Switzerland
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 0021-972X ISBN Medium
Area Expedition Conference
Notes PMID:22188742 Approved no
Call Number IDA @ john @ Serial 301
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Author (up) Gooley, J.J.; Chamberlain, K.; Smith, K.A.; Khalsa, S.B.S.; Rajaratnam, S.M.W.; Van Reen, E.; Zeitzer, J.M.; Czeisler, C.A.; Lockley, S.W.
Title Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans Type Journal Article
Year 2011 Publication The Journal of Clinical Endocrinology and Metabolism Abbreviated Journal J Clin Endocrinol Metab
Volume 96 Issue 3 Pages E463-72
Keywords Adolescent; Adult; Female; Humans; *Light; *Lighting; Male; Melatonin/*blood; Sleep/physiology; Time Factors; Young Adult
Abstract CONTEXT: Millions of individuals habitually expose themselves to room light in the hours before bedtime, yet the effects of this behavior on melatonin signaling are not well recognized. OBJECTIVE: We tested the hypothesis that exposure to room light in the late evening suppresses the onset of melatonin synthesis and shortens the duration of melatonin production. DESIGN: In a retrospective analysis, we compared daily melatonin profiles in individuals living in room light (<200 lux) vs. dim light (<3 lux). PATIENTS: Healthy volunteers (n = 116, 18-30 yr) were recruited from the general population to participate in one of two studies. SETTING: Participants lived in a General Clinical Research Center for at least five consecutive days. INTERVENTION: Individuals were exposed to room light or dim light in the 8 h preceding bedtime. OUTCOME MEASURES: Melatonin duration, onset and offset, suppression, and phase angle of entrainment were determined. RESULTS: Compared with dim light, exposure to room light before bedtime suppressed melatonin, resulting in a later melatonin onset in 99.0% of individuals and shortening melatonin duration by about 90 min. Also, exposure to room light during the usual hours of sleep suppressed melatonin by greater than 50% in most (85%) trials. CONCLUSIONS: These findings indicate that room light exerts a profound suppressive effect on melatonin levels and shortens the body's internal representation of night duration. Hence, chronically exposing oneself to electrical lighting in the late evening disrupts melatonin signaling and could therefore potentially impact sleep, thermoregulation, blood pressure, and glucose homeostasis.
Address Division of Sleep Medicine, Brigham and Women's Hospital and Harvard Medical School, 221 Longwood Avenue, Boston, Massachusetts 02115, USA. gmsjjg@nus.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 0021-972X ISBN Medium
Area Expedition Conference
Notes PMID:21193540; PMCID:PMC3047226 Approved no
Call Number IDA @ john @ Serial 139
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Author (up) Schernhammer, E.S.; Schulmeister, K.
Title Melatonin and cancer risk: does light at night compromise physiologic cancer protection by lowering serum melatonin levels? Type Journal Article
Year 2004 Publication British Journal of Cancer Abbreviated Journal Br J Cancer
Volume 90 Issue 5 Pages 941-943
Keywords Human Health; Animals; Circadian Rhythm/*radiation effects; Humans; Light/*adverse effects; Melatonin/*blood; Neoplasms/blood/*etiology; Risk Factors
Abstract The suprachiasmatic nuclei in the hypothalamus, one of the most important physiological determinants of alertness and performance, drive a circadian pacemaker in mammals, with an intrinsic period averaging 24 h. Light is the primary stimulus to the disruption and resetting of this pacemaker, which is expressed in changing melatonin rhythms. Melatonin production in humans decreases when people are exposed to light at night. Since melatonin shows potential oncostatic action in a variety of tumours, it is possible that lowered serum melatonin levels caused by exposure to light at night enhance the general tumour development. Cancer is the second leading cause of death in industrialised countries like the United States, where a significant proportion of workers engage in shift work, making a hypothesised relation between light exposure at night and cancer risk relevant. Observational studies support an association between night work and cancer risk. We hypothesise that the potential primary culprit for this observed association is the lack of melatonin, a cancer-protective agent whose production is severely diminished in people exposed to light at night.
Address Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, 181 Longwood Avenue, Boston, MA 02115, USA. eva.schernhammer@channing.harvard.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 0007-0920 ISBN Medium
Area Expedition Conference
Notes PMID:14997186; PMCID:PMC2409637 Approved no
Call Number LoNNe @ kagoburian @ Serial 805
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Author (up) Srinivasan, V.; Smits, M.; Spence, W.; Lowe, A.D.; Kayumov, L.; Pandi-Perumal, S.R.; Parry, B.; Cardinali, D.P.
Title Melatonin in mood disorders Type Journal Article
Year 2006 Publication The World Journal of Biological Psychiatry : the Official Journal of the World Federation of Societies of Biological Psychiatry Abbreviated Journal World J Biol Psychiatry
Volume 7 Issue 3 Pages 138-151
Keywords Human Health; Antidepressive Agents/therapeutic use; Biological Markers/blood; Bipolar Disorder/diagnosis/drug therapy/*physiopathology; Circadian Rhythm/drug effects/physiology; Depressive Disorder/diagnosis/drug therapy/*physiopathology; Depressive Disorder, Major/diagnosis/drug therapy/physiopathology; Humans; Melatonin/*blood/therapeutic use; Phototherapy; Seasonal Affective Disorder/diagnosis/physiopathology; Sleep Disorders, Circadian Rhythm/diagnosis/drug therapy/physiopathology; Treatment Outcome
Abstract The cyclic nature of depressive illness, the diurnal variations in its symptomatology and the existence of disturbed sleep-wake and core body temperature rhythms, all suggest that dysfunction of the circadian time keeping system may underlie the pathophysiology of depression. As a rhythm-regulating factor, the study of melatonin in various depressive illnesses has gained attention. Melatonin can be both a 'state marker' and a 'trait marker' of mood disorders. Measurement of melatonin either in saliva or plasma, or of its main metabolite 6-sulfatoxymelatonin in urine, have documented significant alterations in melatonin secretion in depressive patients during the acute phase of illness. Not only the levels but also the timing of melatonin secretion is altered in bipolar affective disorder and in patients with seasonal affective disorder (SAD). A phase delay of melatonin secretion takes place in SAD, as well as changes in the onset, duration and offset of melatonin secretion. Bright light treatment, that suppresses melatonin production, is effective in treating bipolar affective disorder and SAD, winter type. This review discusses the role of melatonin in the pathophysiology of bipolar disorder and SAD.
Address Department of Physiology, School of Medical Sciences, University Sains Malaysia, Kubang Kerian, Kota Bharu, Kelantan
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 1562-2975 ISBN Medium
Area Expedition Conference
Notes PMID:16861139 Approved no
Call Number LoNNe @ kagoburian @ Serial 816
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Author (up) West, K.E.; Jablonski, M.R.; Warfield, B.; Cecil, K.S.; James, M.; Ayers, M.A.; Maida, J.; Bowen, C.; Sliney, D.H.; Rollag, M.D.; Hanifin, J.P.; Brainard, G.C.
Title Blue light from light-emitting diodes elicits a dose-dependent suppression of melatonin in humans Type Journal Article
Year 2011 Publication Journal of Applied Physiology (Bethesda, Md. : 1985) Abbreviated Journal J Appl Physiol (1985)
Volume 110 Issue 3 Pages 619-626
Keywords Circadian Rhythm/*physiology/*radiation effects; Color; Dose-Response Relationship, Radiation; Humans; Lighting/*methods; Melatonin/*blood; Metabolic Clearance Rate/radiation effects; Photic Stimulation/*methods; Radiation Dosage; Retina/*physiology/*radiation effects; Semiconductors; Young Adult; blue light
Abstract Light suppresses melatonin in humans, with the strongest response occurring in the short-wavelength portion of the spectrum between 446 and 477 nm that appears blue. Blue monochromatic light has also been shown to be more effective than longer-wavelength light for enhancing alertness. Disturbed circadian rhythms and sleep loss have been described as risk factors for astronauts and NASA ground control workers, as well as civilians. Such disturbances can result in impaired alertness and diminished performance. Prior to exposing subjects to short-wavelength light from light-emitting diodes (LEDs) (peak lambda = 469 nm; 1/2 peak bandwidth = 26 nm), the ocular safety exposure to the blue LED light was confirmed by an independent hazard analysis using the American Conference of Governmental Industrial Hygienists exposure limits. Subsequently, a fluence-response curve was developed for plasma melatonin suppression in healthy subjects (n = 8; mean age of 23.9 +/- 0.5 years) exposed to a range of irradiances of blue LED light. Subjects with freely reactive pupils were exposed to light between 2:00 and 3:30 AM. Blood samples were collected before and after light exposures and quantified for melatonin. The results demonstrate that increasing irradiances of narrowband blue-appearing light can elicit increasing plasma melatonin suppression in healthy subjects (P < 0.0001). The data were fit to a sigmoidal fluence-response curve (R(2) = 0.99; ED(50) = 14.19 muW/cm(2)). A comparison of mean melatonin suppression with 40 muW/cm(2) from 4,000 K broadband white fluorescent light, currently used in most general lighting fixtures, suggests that narrow bandwidth blue LED light may be stronger than 4,000 K white fluorescent light for suppressing melatonin.
Address Dept. of Neurology, Thomas Jefferson Univ., Philadelphia, Pennsylvania 19107, 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 0161-7567 ISBN Medium
Area Expedition Conference
Notes PMID:21164152 Approved no
Call Number IDA @ john @ Serial 287
Permanent link to this record