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Author Higuchi, S.; Nagafuchi, Y.; Lee, S.-I.; Harada, T. url  doi
openurl 
  Title Influence of Light at Night on Melatonin Suppression in Children Type Journal Article
  Year 2014 Publication The Journal of Clinical Endocrinology and Metabolism Abbreviated Journal J Clin Endocrinol Metab  
  Volume 99 Issue 9 Pages 3298-3303  
  Keywords melatonin; light at night; photobiology; children  
  Abstract Context: The sensitivity of melatonin to light suppression is expected to be higher in children since children have large pupils and pure crystal lenses. However, melatonin suppression by light in children remains unclear. Objective: We investigated whether light-induced melatonin suppression in children is larger than that in adults. Methods: Thirty-three healthy primary school children (mean age: 7.4 +/- 1.8 yr) and 29 healthy adults (mean age: 41.2 +/- 4.8 yr) participated in two experiments. In the first experiment, salivary melatonin concentrations in 13 children and 13 adults were measured at night under a dim light (< 30 lx) and moderately bright light (580 lx) in an experimental facility. Pupil diameters were also measured under dim light and bright light. In the second experiment, melatonin concentrations in 20 children and 16 adults were measured under dim light in the experimental facility and under room light at home (illuminance 140.0 +/- 82.7 lx). Results: In the experiment 1, the melatonin concentration was significantly decreased by exposure to moderately bright light in both adults and children. Melatonin suppression was significantly larger in children (88.2%, n=5) than in adults (46.3%, n=6) (p<0.01), although the data for some participants were excluded because melatonin concentrations had not yet risen. In the experiment 2, melatonin secretion was significantly suppressed by room light at home in children (n=15) (p<0.05) but not in adults (n=11). Conclusion: We found that the percentage of melatonin suppression by light in children was almost twice that in adults, suggesting that melatonin in children is more sensitive than that in adults to light at night.  
  Address (up) Department of Human Science, Faculty of Design, Kyushu University, Fukuoka, Japan  
  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:24840814 Approved no  
  Call Number IDA @ john @ Serial 300  
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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 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 (up) Department of Neuroscience, Ohio State University, Biomedical Research Tower #618, 460 West 12th Avenue, Columbus, OH, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0091-3022 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1062  
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Author Ikeno, T.; Weil, Z.M.; Nelson, R.J. url  doi
openurl 
  Title Dim light at night disrupts the short-day response in Siberian hamsters Type Journal Article
  Year 2014 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol  
  Volume 197 Issue Pages 56-64  
  Keywords 2,4-dinitro-1-flourobenzene; Dnfb; Dth; Eya3; Eyes absent 3; GnIH; GnRH; Immune function; Ld; Lps; Light pollution; Pt; Pelage; Per1; Period1; Photoperiodism; Rfrp; RFamide-related peptide; Scn; Sd; Seasonality; Tsh; TSH receptor; Tshr; dLAN; delayed-type hypersensitivity; dim light at night; gonadotropin-inhibiting hormone; gonadotropin-releasing hormone; lipopolysaccharide; long days; pars tuberalis; short days; suprachiasmatic nuclei; thyroid-stimulating hormone  
  Abstract Photoperiodic regulation of physiology, morphology, and behavior is crucial for many animals to survive seasonally variable conditions unfavorable for reproduction and survival. The photoperiodic response in mammals is mediated by nocturnal secretion of melatonin under the control of a circadian clock. However, artificial light at night caused by recent urbanization may disrupt the circadian clock, as well as the photoperiodic response by blunting melatonin secretion. Here we examined the effect of dim light at night (dLAN) (5lux of light during the dark phase) on locomotor activity rhythms and short-day regulation of reproduction, body mass, pelage properties, and immune responses of male Siberian hamsters. Short-day animals reduced gonadal and body mass, decreased spermatid nuclei and sperm numbers, molted to a whiter pelage, and increased pelage density compared to long-day animals. However, animals that experienced short days with dLAN did not show these short-day responses. Moreover, short-day specific immune responses were altered in dLAN conditions. The nocturnal activity pattern was blunted in dLAN hamsters, consistent with the observation that dLAN changed expression of the circadian clock gene, Period1. In addition, we demonstrated that expression levels of genes implicated in the photoperiodic response, Mel-1a melatonin receptor, Eyes absent 3, thyroid stimulating hormone receptor, gonadotropin-releasing hormone, and gonadotropin-inhibitory hormone, were higher in dLAN animals than those in short-day animals. These results suggest that dLAN disturbs the circadian clock function and affects the molecular mechanisms of the photoperiodic response.  
  Address (up) Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA. Electronic address: randy.nelson@osumc.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 0016-6480 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24362257 Approved no  
  Call Number IDA @ john @ Serial 82  
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Author Fonken, L.K.; Lieberman, R.A.; Weil, Z.M.; Nelson, R.J. url  doi
openurl 
  Title Dim light at night exaggerates weight gain and inflammation associated with a high-fat diet in male mice Type Journal Article
  Year 2013 Publication Endocrinology Abbreviated Journal Endocrinology  
  Volume 154 Issue 10 Pages 3817-3825  
  Keywords Adipose Tissue, White/*immunology/metabolism/pathology; Animals; Antigens, CD11b/biosynthesis/genetics/metabolism; Appetite Regulation/*radiation effects; Arcuate Nucleus/*immunology/metabolism/pathology; Behavior, Animal/radiation effects; Circadian Rhythm; Cytokines/biosynthesis/genetics/metabolism; Diet, High-Fat/*adverse effects; Feeding Behavior/radiation effects; Gene Expression Regulation; Glucose Intolerance/etiology/immunology/metabolism/pathology; I-kappa B Kinase/biosynthesis/genetics/metabolism; Insulin Resistance; Lighting/*adverse effects; Male; Mice; Microglia/immunology/metabolism/pathology; Nerve Tissue Proteins/biosynthesis/genetics/metabolism; Obesity/*etiology/immunology/metabolism/pathology; Random Allocation; *Weight Gain  
  Abstract Elevated nighttime light exposure is associated with symptoms of metabolic syndrome. In industrialized societies, high-fat diet (HFD) and exposure to light at night (LAN) often cooccur and may contribute to the increasing obesity epidemic. Thus, we hypothesized that dim LAN (dLAN) would provoke additional and sustained body mass gain in mice on a HFD. Male mice were housed in either a standard light/dark cycle or dLAN and fed either chow or HFD. Exposure to dLAN and HFD increase weight gain, reduce glucose tolerance, and alter insulin secretion as compared with light/dark cycle and chow, respectively. The effects of dLAN and HFD appear additive, because mice exposed to dLAN that were fed HFD display the greatest increases in body mass. Exposure to both dLAN and HFD also change the timing of food intake and increase TNFalpha and MAC1 gene expression in white adipose tissue after 4 experimental weeks. Changes in MAC1 gene expression occur more rapidly due to HFD as compared with dLAN; after 5 days of experimental conditions, mice fed HFD already increase MAC1 gene expression in white adipose tissue. HFD also elevates microglia activation in the arcuate nucleus of the hypothalamus and hypothalamic TNFalpha, IL-6, and Ikbkb gene expression. Microglia activation is increased by dLAN, but only among chow-fed mice and dLAN does not affect inflammatory gene expression. These results suggest that dLAN exaggerates weight gain and peripheral inflammation associated with HFD.  
  Address (up) Department of Neuroscience, Wexner Medical Center, The Ohio State University, 636 Biomedical Research Tower, 460 West 12th Avenue, Columbus, Ohio 43210. fonken.1@osu.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 0013-7227 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23861373 Approved no  
  Call Number IDA @ john @ Serial 93  
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Author Buonfiglio, D.; Parthimos, R.; Dantas, R.; Cerqueira Silva, R.; Gomes, G.; Andrade-Silva, J.; Ramos-Lobo, A.; Amaral, F.G.; Matos, R.; Sinesio, J.J.; Motta-Teixeira, L.C.; Donato, J.J.; Reiter, R.J.; Cipolla-Neto, J. url  doi
openurl 
  Title Melatonin Absence Leads to Long-Term Leptin Resistance and Overweight in Rats Type Journal Article
  Year 2018 Publication Frontiers in Endocrinology Abbreviated Journal Front Endocrinol (Lausanne)  
  Volume 9 Issue Pages 122  
  Keywords Human health  
  Abstract Melatonin (Mel), a molecule that conveys photoperiodic information to the organisms, is also involved in the regulation of energy homeostasis. Mechanisms of action of Mel in the energy balance remain unclear; herein we investigated how Mel regulates energy intake and expenditure to promote a proper energy balance. Male Wistar rats were assigned to control, control + Mel, pinealectomized (PINX) and PINX + Mel groups. To restore a 24-h rhythm, Mel (1 mg/kg) was added to the drinking water exclusively during the dark phase for 13 weeks. After this treatment period, rats were subjected to a 24-h fasting test, an acute leptin responsiveness test and cold challenge. Mel treatment reduced food intake, body weight, and adiposity. When challenged to 24-h fasting, Mel-treated rats also showed reduced hyperphagia when the food was replaced. Remarkably, PINX rats exhibited leptin resistance; this was likely related to the capacity of leptin to affect body weight, food intake, and hypothalamic signal-transducer and activator of transcription 3 phosphorylation, all of which were reduced. Mel treatment restored leptin sensitivity in PINX rats. An increased hypothalamic expression of agouti-related peptide (Agrp), neuropeptide Y, and Orexin was observed in the PINX group while Mel treatment reduced the expression of Agrp and Orexin. In addition, PINX rats presented lower UCP1 protein levels in the brown adipose tissue and required higher tail vasoconstriction to get a proper thermogenic response to cold challenge. Our findings reveal a previously unrecognized interaction of Mel and leptin in the hypothalamus to regulate the energy balance. These findings may help to explain the high incidence of metabolic diseases in individuals exposed to light at night.  
  Address (up) Department of Physiology and Biophysics, Institute of Biomedical Sciences-I, University of Sao Paulo (USP), Sao Paulo, Brazil  
  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 1664-2392 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29636725; PMCID:PMC5881424 Approved no  
  Call Number NC @ ehyde3 @ Serial 2093  
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