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Author Weil, Z.M.; Borniger, J.C.; Cisse, Y.M.; Abi Salloum, B.A.; Nelson, R.J. url  doi
openurl 
  Title Neuroendocrine control of photoperiodic changes in immune function Type Journal Article
  Year 2014 Publication Frontiers in Neuroendocrinology Abbreviated Journal Frontiers in Neuroendocrinology  
  Volume 37 Issue Pages 108-118  
  Keywords (up) Animals; Photoperiod; Melatonin day length; Seasonality immune function; Neuroendocrine  
  Abstract Seasonal variation in immune function putatively maximizes survival and reproductive success. Day length (photoperiod) is the most potent signal for time of year. Animals typically organize breeding, growth, and behavior to adapt to spatial and temporal niches. Outside the tropics individuals monitor photoperiod to support adaptations favoring survival and reproductive success. Changes in day length allow anticipation of seasonal changes in temperature and food availability that are critical for reproductive success. Immune function is typically bolstered during winter, whereas reproduction and growth are favored during summer. We provide an overview of how photoperiod influences neuronal function and melatonin secretion, how melatonin acts directly and indirectly to govern seasonal changes in immune function, and the manner by which other neuroendocrine effectors such as glucocorticoids, prolactin, thyroid, and sex steroid hormones modulate seasonal variations in immune function. Potential future research avenues include commensal gut microbiota and light pollution influences on photoperiodic responses.  
  Address Department of Neuroscience, Ohio State University, Biomedical Research Tower #618, 460 West 12th Avenue, Columbus, OH, USA  
  Corporate Author Thesis  
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  Series Volume Series Issue Edition  
  ISSN 0091-3022 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1062  
Permanent link to this record
 

 
Author Figueiro, M.G.; Rea, M.S. url  doi
openurl 
  Title The effects of red and blue lights on circadian variations in cortisol, alpha amylase, and melatonin Type Journal Article
  Year 2010 Publication International Journal of Endocrinology Abbreviated Journal Int J Endocrinol  
  Volume 2010 Issue Pages 829351  
  Keywords (up) blue light; red light; circadian rhythm; cortisol; alpha amylase; melatonin; photobiology; suprachiasmatic nuclei; endocrinology  
  Abstract The primary purpose of the present study was to expand our understanding of the impact of light exposures on the endocrine and autonomic systems as measured by acute cortisol, alpha amylase, and melatonin responses. We utilized exposures from narrowband long-wavelength (red) and from narrow-band short-wavelength (blue) lights to more precisely understand the role of the suprachiasmatic nuclei (SCN) in these responses. In a within-subjects experimental design, twelve subjects periodically received one-hour corneal exposures of 40 lux from the blue or from the red lights while continuously awake for 27 hours. Results showed-that, as expected, only the blue light reduced nocturnal melatonin. In contrast, both blue and red lights affected cortisol levels and, although less clear, alpha amylase levels as well. The present data bring into question whether the nonvisual pathway mediating nocturnal melatonin suppression is the same as that mediating other responses to light exhibited by the endocrine and the autonomic nervous systems.  
  Address Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, 3rd Floor, Troy, New York, NY 12180, USA  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1687-8337 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:20652045; PMCID:PMC2905913 Approved no  
  Call Number IDA @ john @ Serial 291  
Permanent link to this record
 

 
Author Arendt, J.; Middleton, B. url  doi
openurl 
  Title Human seasonal and circadian studies in Antarctica (Halley, 75 degrees S) Type Journal Article
  Year 2018 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol  
  Volume 258 Issue Pages 250-258  
  Keywords (up) Human Activities; Acclimatization/*physiology; Actigraphy; Adult; Antarctic Regions; Behavior/*physiology; Circadian Rhythm/*physiology; Darkness; Female; Heart Rate/physiology; Humans; Libido; Light; Male; Melatonin/blood; Photoperiod; *Seasons; Sleep/physiology; Young Adult; *Antarctica; *Circadian; *Light; *Melatonin; *Seasonal  
  Abstract Living for extended periods in Antarctica exposes base personnel to extremes of daylength (photoperiod) and temperature. At the British Antarctic Survey base of Halley, 75 degrees S, the sun does not rise for 110 d in the winter and does not set for 100 d in summer. Photoperiod is the major time cue governing the timing of seasonal events such as reproduction in many species. The neuroendocrine signal providing photoperiodic information to body physiology is the duration of melatonin secretion which reflects the length of the night: longer in the short days of winter and shorter in summer. Light of sufficient intensity and spectral composition serves to suppress production of melatonin and to set the circadian timing and the duration of the rhythm. In humans early observations suggested that bright (>2000 lux) white light was needed to suppress melatonin completely. Shortly thereafter winter depression (Seasonal Affective Disorder or SAD) was described, and its successful treatment by an artificial summer photoperiod of bright white light, sufficient to shorten melatonin production. At Halley dim artificial light intensity during winter was measured, until 2003, at a maximum of approximately 500 lux in winter. Thus a strong seasonal and circadian time cue was absent. It seemed likely that winter depression would be common in the extended period of winter darkness and could be treated with an artificial summer photoperiod. These observations, and predictions, inspired a long series of studies regarding human seasonal and circadian status, and the effects of light treatment, in a small overwintering, isolated community, living in the same conditions for many months at Halley. We found little evidence of SAD, or change in duration of melatonin production with season. However the timing of the melatonin rhythm itself, and/or that of its metabolite 6-sulphatoxymelatonin (aMT6s), was used as a primary marker of seasonal, circadian and treatment changes. A substantial phase delay of melatonin in winter was advanced to summer phase by a two pulse 'skeleton' bright white light treatment. Subsequently a single morning pulse of bright white light was effective with regard to circadian phase and improved daytime performance. The circadian delay evidenced by melatonin was accompanied by delayed sleep (logs and actigraphy): poor sleep is a common complaint in Polar regions. Appropriate extra artificial light, both standard white, and blue enriched, present throughout the day, effectively countered delay in sleep timing and the aMT6s rhythm. The most important factor appeared to be the maximum light experienced. Another manifestation of the winter was a decline in self-rated libido (men only on base at this time). Women on the base showed lower aspects of physical and mental health compared to men. Free-running rhythms were seen in some subjects following night shift, but were rarely found at other times, probably because this base has strongly scheduled activity and leisure time. Complete circadian adaptation during a week of night shift, also seen in a similar situation on North Sea oil rigs, led to problems readapting back to day shift in winter, compared to summer. Here again timed light treatment was used to address the problem. Sleep, alertness and waking performance are critically dependent on optimum circadian phase. Circadian desynchrony is associated with increased risk of major disease in shift workers. These studies provide some groundwork for countering/avoiding circadian desynchrony in rather extreme conditions.  
  Address Biochemistry and Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK. Electronic address: b.middleton@surrey.ac.uk  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0016-6480 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:28526480 Approved no  
  Call Number IDA @ john @ Serial 2248  
Permanent link to this record
 

 
Author Anisimov, V. N. url  openurl
  Title Light pollution, reproductive function and cancer risk Type Journal Article
  Year 2006 Publication Neuroendocrinology Letters Abbreviated Journal  
  Volume 27 Issue 1-2 Pages 35-52  
  Keywords (up) Human Health  
  Abstract At present, light pollution (exposure to light-at-night) both in the form of occupational exposure during night work and as a personal choice and life style, is experienced by numerous night-active members of our society. Disruption of the circadian rhythms induced by light pollution has been associated with cancer in humans. There are epidemiological evidences of increased breast and colon cancer risk in shift workers. An inhibition of the pineal gland function with exposure to the constant light (LL) regimen promoted carcinogenesis whereas the light deprivation inhibits the carcinogenesis. Treatment with pineal indole hormone melatonin inhibits carcinogenesis in pinealectomized rats or animals kept at the standard light/dark regimen (LD) or at the LL regimen. These observations might lead to use melatonin for cancer prevention in groups of humans at risk of light pollution.  
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  Notes Approved no  
  Call Number LoNNe @ kagoburian @ Serial 703  
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Author Obayashi, K.; Saeki, K.; Kurumatani, N. url  doi
openurl 
  Title Ambient Light Exposure and Changes in Obesity Parameters: A Longitudinal Study of the HEIJO-KYO Cohort Type Journal Article
  Year 2016 Publication The Journal of Clinical Endocrinology and Metabolism Abbreviated Journal J Clin Endocrinol Metab  
  Volume Issue Pages jc20154123  
  Keywords (up) Human Health  
  Abstract CONTEXT: Previous epidemiological studies have suggested an association between nighttime light levels and the prevalence of obesity, although evidence is limited to cross-sectional studies. OBJECTIVE: To evaluate the longitudinal association between ambient light exposure and the subsequent changes in obesity parameters. DESIGN AND PARTCIPANTS: Data from 1,110 elderly participants at baseline (mean age, 71.9 years) and data from 766 at follow-up (median, 21 months) were included in this prospective population-based study. MEASURES: Time-dependent ambient light exposure based on objective measurements and changes in the waist-to-height ratio (WHtR) and body mass index (BMI) were measured. RESULTS: Multivariable mixed-effect linear regression models showed a significant association between light exposure and the %WHtR gain; this was independent of potential confounders (e.g., caloric intake, physical activity, and sleep/wake parameters). Nighttime or evening exposure to higher light intensity was significantly associated with subsequent %WHtR gain. Morning exposure to a longer time >/=500 lux or nighttime exposure to a longer time <3 lux was significantly associated with subsequent %WHtR loss. These association trends were nearly consistent when the BMI was used as an obesity parameter. Increased nighttime light exposure (mean >/=3 vs. <3 lux) was estimated to correspond to a 10.2% WHtR gain and 10.0% increase in BMI over 10 years. CONCLUSIONS: Ambient light exposure, such as increased nighttime or evening light exposure and decreased morning light exposure, was independently associated with subsequent increases in obesity parameters. Further interventional studies are warranted to establish an optimal controlled lighting environment as a preventive option against obesity.  
  Address Department of Community Health and Epidemiology, Nara Medical University School of Medicine, Nara, Japan  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0021-972X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:27383113 Approved no  
  Call Number LoNNe @ kyba @ Serial 1483  
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