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melatonin acrophase

Nan Jiang, Zixu Wang, Jing Cao, Yulan Dong, Yaoxing Chen
The avian pineal gland is a master clock that can receive external photic cues and translate them into output rhythms. To clarify whether a shift in light wavelength can influence the circadian expression in chick pineal gland, a total of 240 Arbor Acre male broilers were exposed to white light (WL), red light (RL), green light (GL) or blue light (BL). After 2weeks light illumination, circadian expressions of seven core clock genes in pineal gland and the level of melatonin in plasma were examined. The results showed after illumination with monochromatic light, 24h profiles of all clock gene mRNAs retained circadian oscillation, except that RL tended to disrupt the rhythm of cCry2...
September 13, 2016: Journal of Photochemistry and Photobiology. B, Biology
Caroline Luísa Quiles, Melissa Alves Braga de Oliveira, André Comiran Tonon, Maria Paz Loayza Hidalgo
3A substantial amount of experimental models designed to understand rhythms entrainment and the effects of different regimens of light exposure on health have been proposed. However, many of them do not relate to what occurs in real life. Our objective was to evaluate the influence of "seasonal-like" variation in light/dark cycles on biological rhythms. Twenty adult male Wistar rats were assigned to three groups: control (CT), kept in 12:12 light/dark (LD) cycle; long photoperiod/short photoperiod (LP/SP), kept in 16...
2016: Chronobiology International
Zeeshan Ahmad Khan, Thangal Yumnamcha, Chongtham Rajiv, Haobijam Sanjita Devi, Gopinath Mondal, Sh Dharmajyoti Devi, Rupjyoti Bharali, Asamanja Chattoraj
The present study on zebrafish (Danio rerio) is the first attempt to demonstrate the circadian mRNA expression of melatonin biosynthesizing enzyme genes (Tph1a, Aanat1, Aanat2 and Hiomt) and clock associated genes (Bmal1a, Clock1a, Per1b, Per2 and Cry2a) in the ovary with a comparison to whole brain in normal (LD=12h L:12h D) and altered photic conditions (continuous dark, DD; continuous light, LL). Moreover, the present study also confirmed the ability of zebrafish ovary to biosynthesize melatonin both in vivo and in vitro with a significant difference at day and night...
July 1, 2016: General and Comparative Endocrinology
Sourav Mukherjee, Saumen Kumar Maitra
Influences of starvation, re-feeding and time of food supply on daily rhythm features of melatonin (5-methoxy-N-acetyltryptamine) and its key regulator AANAT (arylalkylamine N-acetyltransferase) protein in the gut tissues were separately evaluated in carp Catla catla. The first experiment was aimed at demonstration of duration dependent effects of starvation and re-feeding after starvation on the daily profiles and rhythm features of gut melatonin and AANAT. Accordingly, juvenile carp were randomly distributed in three groups, which were (a) provided with balanced diet daily at a fixed time, that is, 10:00 clock hour or zeitgeber time (ZT) 4 (control), or (b) starved (for 2-, 4-, 6- or 8 days), or (c) initially starved for 8 days and then re-fed (for 2-, 4-, 6-, 8-, 12- or 16 days) daily with the same food and at the time (ZT4) used for control fish...
2015: Chronobiology International
Roberto C Leonardo-Mendonça, Antonio Martinez-Nicolas, Carlos de Teresa Galván, Javier Ocaña-Wilhelmi, Iryna Rusanova, Eduardo Guerra-Hernández, Germaine Escames, Darío Acuña-Castroviejo
Exercise can induce circadian phase shifts depending on the duration, intensity and frequency. These modifications are of special meaning in athletes during training and competition. Melatonin, which is produced by the pineal gland in a circadian manner, behaves as an endogenous rhythms synchronizer, and it is used as a supplement to promote resynchronization of altered circadian rhythms. In this study, we tested the effect of melatonin administration on the circadian system in athletes. Two groups of athletes were treated with 100 mg day(-1) of melatonin or placebo 30 min before bed for four weeks...
2015: Chronobiology International
Gorica Micic, Nicole Lovato, Michael Gradisar, Helen J Burgess, Sally A Ferguson, David J Kennaway, Leon Lack
A significant delay in the timing of endogenous circadian rhythms has been associated with delayed sleep phase disorder (DSPD). More recently, other mechanisms have also been proposed to account for this disorder. To further explore the etiology of DSPD, the present study compared nocturnal melatonin profiles of 26 DSPD patients (18 males, 8 females; age, 21.73 ± 4.98 years) and 17 normally timed good sleepers (10 males, 7 females; age, 23.82 ± 5.23 years) in a time-free, dim-light (<10 lux) laboratory environment...
October 2015: Journal of Biological Rhythms
Angela M Ramos-Lobo, Daniella C Buonfiglio, José Cipolla-Neto
BACKGROUND: In mammals, the temperature rhythm is regulated by the circadian pacemaker located in the suprachiasmatic nuclei, and is considered a "marker rhythm". Melatonin, the pineal gland hormone, is a major regulator of the endogenous rhythms including body temperature. Its production is influenced by many factors, such as type 1 diabetes mellitus. In rats, diabetes leads to hypothermia and reduced melatonin synthesis; insulin treatment reestablishes both. AIM: To study the body temperature daily rhythm of diabetic animals and the effects of insulin and/or melatonin treatment on its structure...
2015: Diabetology & Metabolic Syndrome
M A Bonmati-Carrion, B Middleton, V L Revell, D J Skene, M A Rol, J A Madrid
Since there is less movement during sleep than during wake, the recording of body movements by actigraphy has been used to indirectly evaluate the sleep-wake cycle. In general, most actigraphic devices are placed on the wrist and their measures are based on acceleration detection. Here, we propose an alternative way of measuring actigraphy at the level of the arm for joint evaluation of activity and body position. This method analyzes the tilt of three axes, scoring activity as the cumulative change of degrees per minute with respect to the previous sampling, and measuring arm tilt for the body position inference...
June 2015: Chronobiology International
Francine Harb, Maria Paz Hidalgo, Betina Martau
The diurnal light cycle has a crucial influence on all life on earth. Unfortunately, modern society has modified this life-governing cycle by stressing maximum production and by giving insufficient attention to the ecological balance and homeostasis of the human metabolism. The aim of this study is to evaluate the effects of exposure or lack of exposure to natural light in a rest/activity rhythm on cortisol and melatonin levels, as well as on psychological variables in humans under natural conditions. This is a cross-sectional study...
April 2015: Chronobiology International
Inés Gómez-Acebo, Trinidad Dierssen-Sotos, Kyriaki Papantoniou, María Teresa García-Unzueta, María Francisca Santos-Benito, Javier Llorca
The present study aims to compare 6-sulfatoxymelatonin (aMT6s) secretion patterns and levels of cortisol and sex hormones (estradiol, progesterone, DHEA, DHEAS, and testosterone) among rotating night-shift workers and day-shift workers. We performed a cross-sectional study in Cantabria (northern Spain) including 136 women (73 day-shift workers and 63 rotating night-shift workers). Blood and urine samples were obtained after two consecutive working days. Differences in means were estimated using ANCOVA, stratified by menopausal status, ovulation phase, and adjusted for season, age, body mass index, consumption of cigarettes in the last 24 h...
February 2015: Chronobiology International
Eirini Kalliolia, Edina Silajdžić, Rajasree Nambron, Nathan R Hill, Anisha Doshi, Chris Frost, Hilary Watt, Peter Hindmarsh, Maria Björkqvist, Thomas T Warner
This study was undertaken to determine whether the production of melatonin, a hormone regulating sleep in relation to the light/dark cycle, is altered in Huntington's disease. We analyzed the circadian rhythm of melatonin in a 24-hour study of cohorts of control, premanifest, and stage II/III Huntington's disease subjects. The mean and acrophase melatonin concentrations were significantly reduced in stage II/III Huntington's disease subjects compared with controls. We also observed a nonsignificant trend toward reduced mean and acrophase melatonin in premanifest Huntington's disease subjects...
October 2014: Movement Disorders: Official Journal of the Movement Disorder Society
Daniella C Buonfiglio, André Malan, Cristina Sandu, Catherine Jaeger, José Cipolla-Neto, David Hicks, Marie-Paule Felder-Schmittbuhl
PURPOSE: Circadian rhythms are central to vision and retinal physiology. A circadian clock located within the retina controls various rhythmic processes including melatonin synthesis in photoreceptors. In the present study, we evaluated the rhythmic expression of clock genes and clock output genes in retinal explants maintained for several days in darkness. METHODS: Retinas were dissected from Wistar rats, either wild-type or from the Per1-luciferase transgenic line housed under a daily 12 h:12 h light-dark cycle (LD12/12), and put in culture at zeitgeber time (ZT) 12 on semipermeable membranes...
2014: Molecular Vision
Elena Toffol, Nea Kalleinen, Jari Haukka, Olli Vakkuri, Timo Partonen, Päivi Polo-Kantola
OBJECTIVES: Melatonin levels decrease physiologically with age, and possibly with the transition to menopause. The plausible influence of hormone therapy (HT) on melatonin is poorly understood. The aim of this randomized, placebo-controlled, double-blind trial was to investigate the effect of HT administration on serum melatonin concentrations in late premenopausal and postmenopausal women. STUDY DESIGN: Analyses were carried out among 17 late premenopausal and 18 postmenopausal healthy women who participated in a prospective HT study in Finland...
April 2014: Maturitas
I F Labunets
The interrelations of circannual rhythms of the functional state of pineal gland, hypophysis, adrenal cortex, thymus in healthy women and men from 20 to 79 years were studied. Fluctuations of melatonin, ACTH, cortisol and thymic serum factor, which were exchanged in aging (the season peaks of hormones and its acrophase) were found in blood of healthy 20-29 years old people. The changes of rhythmicity of indices were in male earlier (pineal gland and hypophysis over 30 years, thymus and adrenal cortex over 40 years) and more impressive than in women...
2013: Advances in Gerontology, Uspekhi Gerontologii
Charles J Meliska, Luis F Martínez, Ana M López, Diane L Sorenson, Sara Nowakowski, Daniel F Kripke, Jeffrey Elliott, Barbara L Parry
Current research suggests that mood varies from season to season in some individuals, in conjunction with light-modulated alterations in chronobiologic indices such as melatonin and cortisol. The primary aim of this study was to evaluate the effects of seasonal variations in darkness on mood in depressed antepartum women, and to determine the relationship of seasonal mood variations to contemporaneous blood melatonin and cortisol measures; a secondary aim was to evaluate the influence of seasonal factors on measures of melancholic versus atypical depressive symptoms...
November 2013: Chronobiology International
M Garrido, D González-Gómez, M Lozano, C Barriga, S D Paredes, A B Rodríguez
OBJECTIVE: In the present work, we evaluated the effect of the intake of a Jerte Valley cherry-based product (JVCP), compared to a placebo product, on sleep quality, urinary 6-sulfatoxymelatonin (aMT6-s) levels and the serum concentration of interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α) and interleukin-8 (IL-8). DESIGN: This was a blind, placebo-controlled, randomized, crossover study. SETTING: University of Extremadura (Spain)...
2013: Journal of Nutrition, Health & Aging
Vural Fidan, Hamit Hakan Alp, Mustafa Gozeler, Onder Karaaslan, Omer Binay, Cemal Cingi
OBJECTIVE: Allergic rhinitis is an IgE-mediated inflammatory disease which effects 10%-50% of the normal population. The mechanism of its formation and the circadian rhythm of cortisol and melatonin in allergic rhinitis have not been investigated. STUDY DESIGN: Salivary levels of melatonin and cortisol were measured by radioimmunoassay in 35 newly diagnosed allergic rhinitis patients and in 23 control subjects matched for age and gender. RESULTS: In the study group; amplitude, baseline and peak levels of salivary melatonin were significantly decreased compared with healty controls (p<0...
September 2013: American Journal of Otolaryngology
María Serón-Ferré, María Luisa Forcelledo, Claudia Torres-Farfan, Francisco J Valenzuela, Auristela Rojas, Marcela Vergara, Pedro P Rojas-Garcia, Monica P Recabarren, Guillermo J Valenzuela
Disruption of the maternal environment during pregnancy is a key contributor to offspring diseases that develop in adult life. To explore the impact of chronodisruption during pregnancy in primates, we exposed pregnant capuchin monkeys to constant light (eliminating the maternal melatonin rhythm) from the last third of gestation to term. Maternal temperature and activity circadian rhythms were assessed as well as the newborn temperature rhythm. Additionally we studied the effect of daily maternal melatonin replacement during pregnancy on these rhythms...
2013: PloS One
Laura Gabriela Nisembaum, A B Tinoco, A L Moure, A L Alonso Gómez, M J Delgado, A I Valenciano
Melatonin has been found in the digestive tract of many vertebrates. However, the enzymatic activity of the arylalkylamine-N-acetyltransferase (AANAT) and the hydroxindole-O-methyltransferase (HIOMT), the last two enzymes of melatonin biosynthesis, have been only measured in rat liver. Therefore, the first objective of the present study is to investigate the functionality of these enzymes in the liver and gut of goldfish, analyzing its possible daily changes and comparing its catalytic properties with those from the retina isoforms...
May 2013: Neurochemistry International
Cai-Xia Li, Dong-Dong Liang, Guo-Hao Xie, Bao-Li Cheng, Qi-Xing Chen, Shui-Jing Wu, Jun-Lu Wang, William Cho, Xiang-Ming Fang
Inflammatory and immune responses, as well as melatonin secretion, are affected by circadian regulation. Abnormal circadian rhythm of melatonin release has been reported to be associated with the later stages of sepsis; however, its role in the early stages of sepsis is unclear. We studied 11 septic and 11 non-septic patients in our intensive care unit (ICU). Peripheral blood was drawn at 4-h intervals on the first day, beginning at 2:00 p.m., over a total period of 24 h. Plasma levels of melatonin, tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) were measured by radioimmunoassay or enzyme-linked immunosorbent assay (ELISA)...
April 2013: Molecular Medicine Reports
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