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Sample records for nocturnal melatonin elevation

  1. Association of Nocturnal Melatonin Secretion With Insulin Resistance in Nondiabetic Young Women

    McMullan, Ciaran J.; CURHAN, Gary C.; Schernhammer, Eva S.; Forman, John P.

    2013-01-01

    Exogenous melatonin ameliorates insulin resistance in animals, while among humans, polymorphisms in the melatonin receptor gene are associated with insulin resistance. We aimed to investigate the association of endogenous nocturnal melatonin secretion with insulin resistance in humans. We analyzed the association between endogenous nocturnal melatonin secretion, estimated by measuring the main melatonin metabolite, 6-sulfatoxymelatonin, from the first morning urinary void, and the prevalence ...

  2. Central Interleukin-1β Suppresses the Nocturnal Secretion of Melatonin.

    Herman, A P; Bochenek, J; Król, K; Krawczyńska, A; Antushevich, H; Pawlina, B; Herman, A; Romanowicz, K; Tomaszewska-Zaremba, D

    2016-01-01

    In vertebrates, numerous processes occur in a rhythmic manner. The hormonal signal reliably reflecting the environmental light conditions is melatonin. Nocturnal melatonin secretion patterns could be disturbed in pathophysiological states, including inflammation, Alzheimer's disease, and depression. All of these states share common elements in their aetiology, including the overexpression of interleukin- (IL-) 1β in the central nervous system. Therefore, the present study was designed to determine the effect of the central injection of exogenous IL-1β on melatonin release and on the expression of the enzymes of the melatonin biosynthetic pathway in the pineal gland of ewe. It was found that intracerebroventricular injections of IL-1β (50 µg/animal) suppressed (P < 0.05) nocturnal melatonin secretion in sheep regardless of the photoperiod. This may have resulted from decreased (P < 0.05) synthesis of the melatonin intermediate serotonin, which may have resulted, at least partially, from a reduced expression of tryptophan hydroxylase. IL-1β also inhibited (P < 0.05) the expression of the melatonin rhythm enzyme arylalkylamine-N-acetyltransferase and hydroxyindole-O-methyltransferase. However, the ability of IL-1β to affect the expression of these enzymes was dependent upon the photoperiod. Our study may shed new light on the role of central IL-1β in the aetiology of disruptions in melatonin secretion. PMID:27212805

  3. Fall in nocturnal serum melatonin during prepuberty and pubescence.

    Waldhauser, F; Weiszenbacher, G; Frisch, H; Zeitlhuber, U; Waldhauser, M; Wurtman, R J

    1984-02-18

    Morning (7:30 AM to 10:00 AM) and nighttime (11:00 PM to 1:00 AM) serum melatonin concentrations were measured in 89 children, adolescents, and young adults. Morning levels (generally 0-20 pg/ml) did not change with sexual maturation or with age. Nighttime levels decreased significantly both with sexual maturation and with age. Nighttime serum melatonin fell from 195 +/- 24 pg/ml (mean +/- SEM) in prepubertal children younger than 7 years of age, to 119 +/- 23 pg/ml in prepubertal children aged 7 years or older, to 49 +/- 4 pg/ml in young adults (puberty stage V). Similarly, nocturnal serum melatonin levels fell from 210 +/- 35 pg/ml in the youngest age group (ages 1-5) to 133 +/- 17 in children aged 5-11 years and to 46 +/- 4 in young adults. Nocturnal plasma concentrations of luteinising hormone measured at various stages of puberty tended to vary inversely with those of melatonin (r = -0.35). Past difficulties in demonstrating a relation between gonadal maturation and human pineal function may have reflected the use of insufficiently sensitive or specific melatonin assays, or serum sampling only during daytime, or the initiation of sample collection when subjects were already too old. PMID:6141425

  4. Effect of inducing nocturnal serum melatonin concentrations in daytime on sleep, mood, body temperature, and performance

    Dollins, A. B.; Zhdanova, I. V.; Wurtman, R. J.; Lynch, H. J.; Deng, M. H.

    1994-01-01

    We examined effects of very low doses of melatonin (0.1-10 mg, orally) or placebo, administered at 1145 h, on sleep latency and duration, mood, performance, oral temperature, and changes in serum melatonin levels in 20 healthy male volunteers. A repeated-measure double-blind Latin square design was used. Subjects completed a battery of tests designed to assess mood and performance between 0930 and 1730 h. The sedative-like effects of melatonin were assessed by a simple sleep test: at 1330 h subjects were asked to hold a positive pressure switch in each hand and to relax with eyes closed while reclining in a quiet darkened room. Latency and duration of switch release, indicators of sleep, were measured. Areas under the time-melatonin concentration curve varied in proportion to the different melatonin doses ingested, and the 0.1- and 0.3-mg doses generated peak serum melatonin levels that were within the normal range of nocturnal melatonin levels in untreated people. All melatonin doses tested significantly increased sleep duration, as well as self-reported sleepiness and fatigue, relative to placebo. Moreover, all of the doses significantly decreased sleep-onset latency, oral temperature, and the number of correct responses on the Wilkinson auditory vigilance task. These data indicate that orally administered melatonin can be a highly potent hypnotic agent; they also suggest that the physiological increase in serum melatonin levels, which occurs around 2100 h daily, may constitute a signal initiating normal sleep onset.

  5. Elevated heart rate and nondipping heart rate as potential targets for melatonin: a review.

    Simko, Fedor; Baka, Tomas; Paulis, Ludovit; Reiter, Russel J

    2016-09-01

    Elevated heart rate is a risk factor for cardiovascular and all-cause mortalities in the general population and various cardiovascular pathologies. Insufficient heart rate decline during the night, that is, nondipping heart rate, also increases cardiovascular risk. Abnormal heart rate reflects an autonomic nervous system imbalance in terms of relative dominance of sympathetic tone. There are only a few prospective studies concerning the effect of heart rate reduction in coronary heart disease and heart failure. In hypertensive patients, retrospective analyses show no additional benefit of slowing down the heart rate by beta-blockade to blood pressure reduction. Melatonin, a secretory product of the pineal gland, has several attributes, which predict melatonin to be a promising candidate in the struggle against elevated heart rate and its consequences in the hypertensive population. First, melatonin production depends on the sympathetic stimulation of the pineal gland. On the other hand, melatonin inhibits the sympathetic system in several ways representing potentially the counter-regulatory mechanism to normalize excessive sympathetic drive. Second, administration of melatonin reduces heart rate in animals and humans. Third, the chronobiological action of melatonin may normalize the insufficient nocturnal decline of heart rate. Moreover, melatonin reduces the development of endothelial dysfunction and atherosclerosis, which are considered a crucial pathophysiological disorder of increased heart rate and pulsatile blood flow. The antihypertensive and antiremodeling action of melatonin along with its beneficial effects on lipid profile and insulin resistance may be of additional benefit. A clinical trial investigating melatonin actions in hypertensive patients with increased heart rate is warranted. PMID:27264986

  6. Effect of inducing nocturnal serum melatonin concentrations in daytime on sleep, mood, body temperature, and performance.

    Dollins, A B; Zhdanova, I.V.; Wurtman, R J; Lynch, H. J.; Deng, M H

    1994-01-01

    We examined effects of very low doses of melatonin (0.1-10 mg, orally) or placebo, administered at 1145 h, on sleep latency and duration, mood, performance, oral temperature, and changes in serum melatonin levels in 20 healthy male volunteers. A repeated-measure double-blind Latin square design was used. Subjects completed a battery of tests designed to assess mood and performance between 0930 and 1730 h. The sedative-like effects of melatonin were assessed by a simple sleep...

  7. Melatonin treatment in children with therapy-resistant monosymptomatic nocturnal enuresis

    Merks, B. T.; Burger, H.; Willemsen, J.; van Gool, J. D.; de Jong, T. P. V. M.

    2012-01-01

    Objective: To evaluate the effects of exogenous melatonin on the frequency of wet nights, on the sleep-wake cycle, and on the melatonin profile in children with therapy-resistant MNE. Patients and methods: 24 patients were included. Patients had to maintain a diary including time of sleep and arousa

  8. Melatonin

    Manchester, Lucien C; Coto-Montes, Ana; Boga, Jose Antonio;

    2015-01-01

    Melatonin is remarkably functionally diverse with actions as a free radical scavenger and antioxidant, circadian rhythm regulator, anti-inflammatory and immunoregulating molecule, and as an oncostatic agent. We hypothesize that the initial and primary function of melatonin in photosynthetic...

  9. Rapid-onset/offset, variably scheduled 60 Hz electric and magnetic field exposure reduces nocturnal serum melatonin concentration in nonhuman primates

    Rogers, W.R.; Smith, H.D. [Southwest Research Inst., San Antonio, TX (United States). Dept. of Biosciences and Bioengineering; Reiter, R.J.; Barlow-Walden, L. [Univ. of Texas Health Science Center, San Antonio, TX (United States). Dept. of Cellular and Structural Biology

    1995-12-31

    Experiments with rodents indicate that power-frequency electric field (EF) or magnetic field (MF) exposure can suppress the normal nocturnal increase in melatonin concentration in pineal gland and blood. In a separate set of three experiments conducted with nonhuman primates, the authors did not observe melatonin suppression as a result of 6 weeks of day-time exposure to combined 60 Hz electric and magnetic fields (E/MF) with regularly schedule ``slow`` E/MF onsets/offsets. The study described here used a different exposure paradigm in which two baboons were exposed to E/MF with ``rapid`` E/MF onsets/offsets accompanied by EF transients not found with slowly ramped E/MF onset/offset; profound reductions in nocturnal serum melatonin concentration were observed in this experiment. If replicated in a more extensive experiment, the observation of melatonin suppression only in the presence of E/MF transients would suggest that very specific exposure parameters determine the effects of 60 Hz E/MF on melatonin.

  10. Melatonin

    Bachmann A

    2015-01-01

    Full Text Available Chemistry: Melatonin is an indolamine which accrues via serotonin from the amino acid L tryptophan. Point of origin: The main point of origin in humans is the epiphysis.br Physiological relevance: – In animals: Due to lighting condition influenced chronobiological processes, melatonin has impact on reproduction and growth. In consequence of its anti-oxidative efficacy, melatonin has protective effects from environmental influences. – In humans: Melatonin can be found in a variety of cells like in lymphocytes and bone marrow cells, the thymus gland and in the gastrointestinal tract as well as in the skin and in the eyes.br There, it exerts numerous paracrine functions. The effects of melatonin in humans are divers and not fully understood yet. Melatonin results in down-regulation of several biological and oxidative processes. It plays a role in the endogenous rhythm formation, is a potent anti-oxidant and has immunomodulatory effects. Of clinical relevance is a potential correlation with the development of breast cancer.br Pharmacotherapy: The field of research and the clinical relevance of chronobiology and the possible indications for the use of melatonin is broad. However, there are not sufficient data on the efficacy and safety of melatonin from clinical trials. Melatonin is used in retarded formulation and is approved for the treatment of sleep disorders in people 55 years of age with disorders in the sleep architecture.br In contrast to benzodiazepines, which are commonly used for the treatment of insomnia, it appears that melatonin does not result in an impairment of psycho-motorics on the following day. The subjective perception of the quality of sleep and the mental performance are improved on the next morning. However, the difference in the response rate compared to placebo is low and therefore melatonin can be considered a weak hypnotic agent only. The rate of recurrent insomnia can not be estimated from the current studies available

  11. Effects of pressure on the skin exerted by clothing on responses of urinary catecholamines and cortisol, heart rate and nocturnal urinary melatonin in humans

    Mori, Yuki; Kioka, Etsuko; Tokura, Hiromi

    2002-09-01

    The study investigated how the pressure exerted on the skin by clothing worn while working in the daytime affected the urinary excretion of adrenaline, noradrenaline and cortisol, heart rate, and also melatonin secretion at night. Nine young women (experiment I) and seven young women (experiment II) participated. Participants wore either a 100% cotton jacket (tight clothes, TC) or a 100% cotton T-shirt (loose clothes, LC). Loose-fitting, 100% cotton tank tops and panties were worn as underwear in both the TC and the LC groups. The main results can be summarized as follows: (1) urinary excretion of adrenaline, noradrenaline and cortisol was facilitated, and the amounts of urinary excretion were significantly higher when TC were worn. Heart rate was significantly higher in the TC group; (2) nocturnal urinary melatonin excretion was significantly greater in the TC group. These results are discussed in terms of an enhancement of diurnal sympathetic nervous system activity caused by pressure on the skin produced by tight clothing.

  12. Melatonin effects on luteinizing hormone in postmenopausal women: a pilot clinical trial NCT00288262

    Kline Lawrence E

    2006-05-01

    Full Text Available Abstract Background In many mammals, the duration of the nocturnal melatonin elevation regulates seasonal changes in reproductive hormones such as luteinizing hormone (LH. Melatonin's effects on human reproductive endocrinology are uncertain. It is thought that the same hypothalamic pulse generator may both trigger the pulsatile release of GnRH and LH and also cause hot flashes. Thus, if melatonin suppressed this pulse generator in postmenopausal women, it might moderate hot flashes. This clinical trial tested the hypothesis that melatonin could suppress LH and relieve hot flashes. Methods Twenty postmenopausal women troubled by hot flashes underwent one week of baseline observation followed by 4 weeks of a randomized controlled trial of melatonin or matched placebo. The three randomized treatments were melatonin 0.5 mg 2.5–3 hours before bedtime, melatonin 0.5 mg upon morning awakening, or placebo capsules. Twelve of the women were admitted to the GCRC at baseline and at the end of randomized treatment for 24-hour sampling of blood for LH. Morning urine samples were collected twice weekly to measure LH excretion. Subjective responses measured throughout baseline and treatment included sleep and hot flash logs, the CESD and QIDS depression self-ratings, and the SAFTEE physical symptom inventory. Results Urinary LH tended to increase from baseline to the end of treatment. Contrasts among the 3 randomized groups were statistically marginal, but there was relative suppression combining the groups given melatonin as contrasted to the placebo group (p Conclusion The data are consistent with the hypothesis that melatonin suppresses LH in postmenopausal women. An effect related to the duration of nocturnal melatonin elevation is suggested. Effects of melatonin on reproductive endocrinology should be studied further in younger women and in men. Larger studies of melatonin effects on postmenopausal symptoms would be worthwhile.

  13. Tryptophan-enriched cereal intake improves nocturnal sleep, melatonin, serotonin, and total antioxidant capacity levels and mood in elderly humans

    Bravo, R.; Matito, S.; Cubero, J.; Paredes, S.D.; Franco, L.; Rivero, M.; Rodríguez, A.B.; Barriga, C.

    2012-01-01

    Melatonin and serotonin rhythms, which exhibit a close association with the endogenous circadian component of sleep, are attenuated with increasing age. This decrease seems to be linked to sleep alterations in the elderly. Chrononutrition is a field of chronobiology that establishes the principle of consuming foodstuffs at times of the day when they are more useful for health, improving, therefore, biorhythms and physical performance. Our aim was to analyze whether the consumption of cereals ...

  14. Do night-active birds lack daily melatonin rhythms? A case study comparing a diurnal and a nocturnal-foraging gull species

    Wikelski, M; Tarlow, EM; Eising, CM; Groothuis, TGG; Gwinner, E; Tarlow, Elisa M.; Groothuis, Ton G.G.; Bairlein, F.

    2006-01-01

    Plasma melatonin concentrations in most animals investigated so far increase at night regardless of whether individuals are day or night active. Nevertheless, daily melatonin amplitudes are often seasonally adjusted to ecological conditions, with birds that breed at high latitudes and migrate during

  15. Effects of intracoronary melatonin on ischemia-reperfusion injury in ST-elevation myocardial infarction

    Ekeløf, Sarah V; Halladin, Natalie L; Jensen, Svend E;

    2016-01-01

    Acute coronary occlusion is effectively treated by primary percutaneous coronary intervention. However, myocardial ischemia-reperfusion injury is at the moment an unavoidable consequence of the procedure. Oxidative stress is central in the development of ischemia-reperfusion injury. Melatonin, an...... endogenous hormone, acts through antioxidant mechanisms and could potentially minimize the myocardial injury. The aim of the experimental study was to examine the cardioprotective effects of melatonin in a porcine closed-chest reperfused infarction model. A total of 20 landrace pigs were randomized to a...... dosage of 200 mg (0.4 mg/mL) melatonin or placebo (saline). The intervention was administered intracoronary and intravenous. Infarct size, area at risk and microvascular obstruction were determined ex vivo by cardiovascular magnetic resonance imaging. Myocardial salvage index was calculated. The plasma...

  16. Impaired growth and elevated Fas receptor expression in PIGA+ stem cells in primary paroxysmal nocturnal hemoglobinuria

    Chen, Rui; Nagarajan, Shanmugam; Prince, Gregory M.; Maheshwari, Uma; Terstappen, Leon W. M. M.; Kaplan, David R.; Stanton L Gerson; Albert, Jeffrey M.; Dunn, Daniel E.; Lazarus, Hillard M.; Medof, M. Edward

    2000-01-01

    The genetic defect underlying paroxysmal nocturnal hemoglobinuria (PNH) has been shown to reside in PIGA, a gene that encodes an element required for the first step in glycophosphatidylinositol anchor assembly. Why PIGA-mutated cells are able to expand in PNH marrow, however, is as yet unclear. To address this question, we compared the growth of affected CD59–CD34+ and unaffected CD59+CD34+ cells from patients with that of normal CD59+CD34+ cells in liquid culture. One hundred FACS-sorted cel...

  17. Nocturnal Asthma

    ... Medical Director, Health Initiatives View full profile Nocturnal Asthma Worsening of asthma at night, or nocturnal asthma, ... give extra protection during the night. More Nocturnal Asthma Information Back to Asthma: Types Print Page Email ...

  18. Clinical Uses of Melatonin in Pediatrics

    Emilio J. Sánchez-Barceló

    2011-01-01

    Full Text Available This study analyzes the results of clinical trials of treatments with melatonin conducted in children, mostly focused on sleep disorders of different origin. Melatonin is beneficial not only in the treatment of dyssomnias, especially delayed sleep phase syndrome, but also on sleep disorders present in children with attention-deficit hyperactivity, autism spectrum disorders, and, in general, in all sleep disturbances associated with mental, neurologic, or other medical disorders. Sedative properties of melatonin have been used in diagnostic situations requiring sedation or as a premedicant in children undergoing anesthetic procedures. Epilepsy and febrile seizures are also susceptible to treatment with melatonin, alone or associated with conventional antiepileptic drugs. Melatonin has been also used to prevent the progression in some cases of adolescent idiopathic scoliosis. In newborns, and particularly those delivered preterm, melatonin has been used to reduce oxidative stress associated with sepsis, asphyxia, respiratory distress, or surgical stress. Finally, the administration of melatonin, melatonin analogues, or melatonin precursors to the infants through the breast-feeding, or by milk formula adapted for day and night, improves their nocturnal sleep. Side effects of melatonin treatments in children have not been reported. Although the above-described results are promising, specific studies to resolve the problem of dosage, formulations, and length of treatment are necessary.

  19. Endogenous melatonin and oxidatively damaged guanine in DNA

    Davanipour, Zoreh; Poulsen, Henrik E; Weimann, Allan;

    2009-01-01

    BACKGROUND: A significant body of literature indicates that melatonin, a hormone primarily produced nocturnally by the pineal gland, is an important scavenger of hydroxyl radicals and other reactive oxygen species. Melatonin may also lower the rate of DNA base damage resulting from hydroxyl radic...

  20. Elevated levels of mitochonrial respiratory complexes activities and ATP production in 17-β-estradiol-induced prolactin-secretory tumor cells in male rats are inhibited by melatonin in vivo and in vitro

    WANG Bao-qiang; YANG Quan-hui; XU Rong-kun; XU Jian-ning

    2013-01-01

    Background Our earlier studies indicate that melatonin inhibits the proliferation of prolactinoma and induces apoptosis of pituitary prolactin-secreting tumor in rats.Melatonin has also been shown to induce apoptosis and to reduce the production of ATP in breast tumor cells.This study analyzed the levels of the four mitochondrial respiratory complexes and the production of ATP and also the effects of melatonin treatment of prolactinoma.Methods In the in vivo study,mitochondria were harvested from control pituitaries or prolactinoma collected from the pituitaries of melatonin-and 17-β-estradiol (E2)-treated male rats.In the in vitro study,prolactinoma cells mitochondria were harvested.Activities of the four mitochondrial respiratory complexes were assayed using fluorometer.ATP production of prolactinoma cells was estimated using bioluminescent methods.Results Elevated levels of four mitochondrial respiratory complexes activities and ATP production were recorded in prolactinoma cells.Moreover,in both in vivo and in vitro studies,melatonin inhibited the activities of mitochondrial respiratory complexes and the production of ATP in prolactinoma cells.Conclusions There is a link between mitochondrial function increase and tumorigenesis.Melatonin induces apoptosis of pituitary prolactin-secreting tumor of rats via the induction of mitochondrial dysfunction and inhibition of energy metabolism.

  1. Nocturnal enuresis

    2007-01-01

    Nocturnal enuresis affects 15−20% of 5-year-old children, 5% of 10-year-old children, and 1−2% of people aged 15 years and over. Without treatment, 15% of affected children will become dry each year. Nocturnal enuresis is not diagnosed in children younger than 5 years, and treatment may be inappropriate for children younger than 7 years.

  2. Nocturnal enuresis

    Kiddoo, Darcie

    2011-01-01

    Nocturnal enuresis affects 15% to 20% of 5-year-old children, 5% of 10-year-old children, and 1% to 2% of people aged 15 years and over. Without treatment, 15% of affected children will become dry each year. Nocturnal enuresis is not diagnosed in children aged

  3. Variability of plasma melatonin level in pony mares (Equus caballus), comparison with the hybrid: mules and with jennies (Equus asinus)

    Guillaume, Daniel; Zarazaga Garcés, Luis Ángel; Malpaux, Benoît; Chemineau, Phileppe

    2006-01-01

    In long-day breeders like horses, the length of nocturnal melatonin secretion is the main messenger of photoperiod. Previous studies have shown that the nocturnal jugular melatonin concentration is lower in horses, than in mules but is unknown in donkeys. The aim of this study was to estimate the inter-animal variability of plasma melatonin concentration in domestic mares and to compare this concentration with those observed in domestic jennies and in their hybrid mules. In the autumn, blood ...

  4. Seasonal Patterns of Melatonin, Cortisol, and Progesterone Secretion in Female Lambs Raised Beneath a 500-kV Transmission Line.

    Lee, Jack M.

    1992-06-01

    Although several kinds of biological effects of electric and magnetic fields have been reported from laboratory studies, few have been independently replicated. When this study was being planned, the suppression of nighttime melatonin in rodents was thought to represent one of the strongest known effects of these fields. The effect had been replicated by a single laboratory for 60-Hz electric fields, and by multiple laboratories for d-c magnetic fields. The primary objective of this study was to determine whether the effect of electric and magnetic fields on melatonin would also occur in sheep exposed to a high voltage transmission line. The specific hypothesis tested by this experiment was as follows: The electrical environment produced by a 60-Hz, 500-kV transmission line causes a depression in nocturnal melatonin in chronically exposed female lambs. This may mimic effects of pinealectomy or constant long-day photoperiods, thus delaying the onset of reproductive cycles. Results of the study do not provide evidence to support the hypothesis. Melatonin concentrations in the sheep exposed to the transmission line showed the normal pattern of low daytime and high nighttime serum levels. As compared to the control group, there were no statistically significant group differences in the mean amplitude, phase, or duration of the nighttime melatonin elevation.

  5. Modeling and measuring the nocturnal drainage flow in a high-elevation, subalpine forest with complex terrain

    Yi, C.; Monson, Russell K.; Zhai, Z.; Anderson, D.E.; Lamb, B.; Allwine, G.; Turnipseed, A.A.; Burns, Sean P.

    2005-01-01

    The nocturnal drainage flow of air causes significant uncertainty in ecosystem CO2, H2O, and energy budgets determined with the eddy covariance measurement approach. In this study, we examined the magnitude, nature, and dynamics of the nocturnal drainage flow in a subalpine forest ecosystem with complex terrain. We used an experimental approach involving four towers, each with vertical profiling of wind speed to measure the magnitude of drainage flows and dynamics in their occurrence. We developed an analytical drainage flow model, constrained with measurements of canopy structure and SF6 diffusion, to help us interpret the tower profile results. Model predictions were in good agreement with observed profiles of wind speed, leaf area density, and wind drag coefficient. Using theory, we showed that this one-dimensional model is reduced to the widely used exponential wind profile model under conditions where vertical leaf area density and drag coefficient are uniformly distributed. We used the model for stability analysis, which predicted the presence of a very stable layer near the height of maximum leaf area density. This stable layer acts as a flow impediment, minimizing vertical dispersion between the subcanopy air space and the atmosphere above the canopy. The prediction is consistent with the results of SF6 diffusion observations that showed minimal vertical dispersion of nighttime, subcanopy drainage flows. The stable within-canopy air layer coincided with the height of maximum wake-to-shear production ratio. We concluded that nighttime drainage flows are restricted to a relatively shallow layer of air beneath the canopy, with little vertical mixing across a relatively long horizontal fetch. Insight into the horizontal and vertical structure of the drainage flow is crucial for understanding the magnitude and dynamics of the mean advective CO2 flux that becomes significant during stable nighttime conditions and are typically missed during measurement of the

  6. Melatonin Promotes Superovulation in Sika Deer (Cervus nippon)

    Liang Wang; Zhi-Yong Zhuo; Wen-Qing Shi; Dun-Xian Tan; Chao Gao; Xiu-Zhi Tian; Lu Zhang; Guang-Bin Zhou; Shi-En Zhu; Peng Yun; Guo-Shi Liu

    2014-01-01

    In this study, the effects of melatonin (MT) on superovulation and reproductive hormones (melatonin, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and PRL) were investigated in female sika deer. Different doses (40 or 80 mg/animal) of melatonin were subcutaneously implanted into deer before the breeding season. Exogenous melatonin administration significantly elevated the serum FSH levels at the time of insemination compared with levels in control animals. During superovulation...

  7. Renal clearance of melatonin

    Editorial Office

    1996-01-01

    Only two publications exist in which actual values for the renal clearance of intact melatonin in man is described. The melatonin clearance values were, however, obtained either after the oral intake of melatonin, or by applying different techniques for the determination of melatonin in urine and plasma. In this study, renal clearance of melatonin was determined during the hours where melatonin concentrations are relatively constant. Melatonin levels in plasma and urine respectively were e...

  8. MELATONIN: POTENTIAL UTILITY FOR IMPROVING PUBLIC HEALTH

    Russel J REITER; Fatih GULTEKIN; Luis J FLORES; Ma Pilar TERRON; Dun-Xian TAN

    2006-04-01

    Full Text Available This review summarizes the beneficial actions of melatonin in various experimental conditions/diseases and identifies where the use of melatonin may be helpful in improving public health. The nightly use of melatonin supplements by humans often improves their sleep and helps correct the circadian dyssynchronization associated with “jet lag”. Additionally, melatonin has been found effective in curtailing the growth of a variety of experimental cancers. Mechanistically, this is achieved by melatonin’s ability to limit fatty acid uptake, especially linoleic acid, by tumor cells. Fatty acids are growth factors for many tumors. Additionally, melatonin inhibits the elevated telomerase activity of tumor cells thus making them more fragile and vulnerable to chemotherapies. Melatonin also may inhibit angiogenesis in tumors by suppressing endothelin-1 production and the indole interferes with the stimulatory action of steroids on hormone-responsive tumors. As an ubiquitously-acting antioxidant, melatonin reduces cardiac damage during ischemia/reperfusion (I/R injury (heart attack and during I/R to the brain (stroke. Melatonin also limits the toxicity of amyloid  peptide and of neurofibrillary tangles, two of the cardinal signs of Alzheimer’s disease. Collectively, these data suggest supplementation with melatonin, whose endogenous levels decrease with age, may improve the quality of life in the aged and, as a consequence, be beneficial for public health generally. [TAF Prev Med Bull 2006; 5(2.000: 131-158

  9. Seasonal Patterns of Melatonin, Cortisol, and Progesterone Secretion in Female Lambs Raised Beneath a 500-KV Transmission Line

    Lee, Jack Monroe, Jr.

    There is ongoing controversy about the possibility of adverse biological effects from environmental exposures to electric and magnetic fields. These fields are produced by all electrical equipment and appliances including electrical transmission lines. The objective of this environmental science study was to investigate the possible effects of a high voltage transmission line on domestic sheep (Ovis aries L.), a species that can often be found near such lines. The study was primarily designed to determine whether a specific effect of electric and magnetic fields found in laboratory animals also occurs in livestock under natural environmental conditions. The effect is the ability of fields, at levels found in the environment, to significantly depress the normally high nocturnal concentrations of the pineal hormone-melatonin. Ten female Suffolk lambs were penned for 10 months directly beneath a 500-kV transmission line near Estacada, Oregon. Ten other lambs of the same type were penned in a control area away from the transmission line where electric and magnetic fields were at ambient levels. Serum melatonin was analyzed by radioimmunoassay (RIA) from 6618 blood samples collected at 0.5 to 3-hour intervals over eight 48-hour periods. Serum progesterone was analyzed by RIA from blood samples collected twice weekly. Serum cortisol was also assayed by RIA from the blood samples collected during the 48-hour samples. Results showed that lambs in both the control and line groups had the typical pattern of melatonin secretion consisting of low daytime and high nighttime serum concentrations. There were no statistically significant differences between groups in melatonin levels, or in the phase or duration of the nighttime melatonin elevation. Age at puberty and number of reproductive cycles also did not differ between groups. Serum cortisol showed a circadian rhythm with highest concentrations during the day. There were, however, no differences in cortisol concentrations

  10. Gut Melatonin in Vertebrates: Chronobiology and Physiology

    Dr. Saumen Kumar Maitra

    2015-07-01

    Full Text Available Melatonin, following discovery in the bovine pineal gland, has been detected in several extra-pineal sources including gastrointestinal tract or gut. Arylalkylamine N-acetyltransferase (AANAT is the key regulator of its biosynthesis. Melatonin in pineal is rhythmically produced with a nocturnal peak in synchronization with environmental light-dark cycle. A recent study on carp reported first that melatonin levels and intensity of a ~23kDa AANAT protein in each gut segment also exhibit significant daily variations but, unlike pineal, show a peak at midday in all seasons. Extensive experimental studies ruled out direct role of light-dark conditions in determining temporal pattern of gut melatoninergic system in carp, and opened up possible role of environmental non-photic cue(s as its synchronizer. Based on mammalian findings, physiological significance of gut derived melatonin also appears unique because its actions at local levels sharing paracrine and/or autocrine functions have been emphasized. The purpose of this mini-review is to summarize existing data on the chronobiology and physiology of gut melatonin and to emphasize their relation with the same hormone derived in the pineal in vertebrates including fish.

  11. Homeobox genes and melatonin synthesis

    Rohde, Kristian; Møller, Morten; Rath, Martin Fredensborg

    2014-01-01

    Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a c......AMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processes, are also expressed in the mature rodent pineal gland. Among these, the cone-rod homeobox (CRX......) transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating c...

  12. Melatonin treatment in an institutionalised child with psychomotor retardation and an irregular sleep-wake pattern

    Pillar, G; Etzioni, A; Shahar, E; Lavie, P.

    1998-01-01

    An institutionalised 13 year old girl with psychomotor retardation suffered from an irregular sleep-wake pattern. Multiple measurements of urinary sulphatoxymelatonin (aMT6) concentrations were abnormally low, without any significant day-night differences. Administration of exogenous melatonin (3 mg) at 18:00 resulted in increased nocturnal urinary aMT6 concentrations and improvements in her sleep-wake pattern. Melatonin may help disabled children suffering from sleep disorders.

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  13. Effect of melatonin administration on subjective sleep quality in chronic obstructive pulmonary disease

    D.M. Nunes; R.M.S. Mota; M.O. Machado; E.D.B. Pereira; de Bruin, V. M. S.; P.F.C. de Bruin

    2008-01-01

    Disturbed sleep is common in chronic obstructive pulmonary disease (COPD). Conventional hypnotics worsen nocturnal hypoxemia and, in severe cases, can lead to respiratory failure. Exogenous melatonin has somnogenic properties in normal subjects and can improve sleep in several clinical conditions. This randomized, double-blind, placebo-controlled study was carried out to determine the effects of melatonin on sleep in COPD. Thirty consecutive patients with moderate to very severe COPD were ini...

  14. Melatonin and sleep-related problems in children with intractable epilepsy.

    Elkhayat, Hamed A; Hassanein, Sahar M; Tomoum, Hoda Y; Abd-Elhamid, Iman A; Asaad, Tarek; Elwakkad, Amany S

    2010-04-01

    Children with epilepsy have high rates of sleep problems. Melatonin has been advocated in treatment of sleep disorders, and its beneficial effect has been confirmed in insomnia. The aim of this study was to assess melatonin levels in children with intractable epilepsy and its relation to pattern of sleep and characteristics of seizure disorder, as well as the effect of melatonin therapy on those parameters. The study was conducted on 23 children with intractable epilepsy and 14 children with controlled seizures. Patients were evaluated by psychometric sleep assessment and assay of diurnal and nocturnal melatonin levels. Children with intractable epilepsy received oral melatonin before bedtime. They were reassessed after 3 months. Children with intractable epilepsy had higher scores for each category of sleep walking, forcible teeth grinding, and sleep apnea. At the end of therapeutic trial, patients with intractable epilepsy exhibited significant improvement in bedtime resistance, sleep duration, sleep latency, frequent nocturnal arousals, sleep walking, excessive daytime sleepiness, nocturnal enuresis, forcible teeth grinding, sleep apnea, and Epworth sleepiness scores. There was also significant reduction in seizure severity. Thus, use of melatonin in patients with intractable seizures was associated with improvement of both many sleep-related phenomena and the severity of seizures. PMID:20304327

  15. Ocular input for human melatonin regulation: relevance to breast cancer

    Glickman, Gena; Levin, Robert; Brainard, George C.

    2002-01-01

    The impact of breast cancer on women across the world has been extensive and severe. As prevalence of breast cancer is greatest in industrialized regions, exposure to light at night has been proposed as a potential risk factor. This theory is supported by the epidemiological observations of decreased breast cancer in blind women and increased breast cancer in women who do shift-work. In addition, human, animal and in vitro studies which have investigated the melatonin-cancer dynamic indicate an apparent relationship between light, melatonin and cancer, albeit complex. Recent developments in understanding melatonin regulation by light in humans are examined, with particular attention to factors that contribute to the sensitivity of the light-induced melatonin suppression response. Specifically, the role of spectral characteristics of light is addressed, and recent relevant action spectrum studies in humans and other mammalian species are discussed. Across five action spectra for circadian and other non-visual responses, a peak sensitivity between 446-484 nm was identified. Under highly controlled exposure circumstances, less than 1 lux of monochromatic light elicited a significant suppression of nocturnal melatonin. In view of the possible link between light exposure, melatonin suppression and cancer risk, it is important to continue to identify the basic related ocular physiology. Visual performance, rather than circadian function, has been the primary focus of architectural lighting systems. It is now necessary to reevaluate lighting strategies, with consideration of circadian influences, in an effort to maximize physiological homeostasis and health.

  16. New developments in the treatment of primary insomnia in elderly patients: focus on prolonged-release melatonin

    Vigo DE

    2012-10-01

    Full Text Available Daniel P Cardinali, María F Vidal, Daniel E VigoDepartment of Teaching and Research, Faculty of Medical Sciences, Pontificia Universidad Católica Argentina, Buenos Aires, ArgentinaAbstract: A temporal relationship between the nocturnal rise in melatonin secretion and the increase in sleep propensity at the beginning of the night, coupled with the sleep-promoting effects of exogenous melatonin, indicate that melatonin is involved in the regulation of sleep. This action is attributed to the MT1 and MT2 melatonin receptors present in the hypothalamic suprachiasmatic nucleus and other brain areas. The sleep-promoting actions of melatonin, which are demonstrable in healthy humans, have been found to be useful in subjects suffering from circadian rhythm sleep disorders and in elderly patients, who had low nocturnal melatonin production and secretion. The effectiveness of melatonin in treating sleep disturbances in these patients is relevant because the sleep-promoting compounds that are usually prescribed, such as benzodiazepines and related drugs, have many adverse effects, such as next-day hangover, dependence, and impairment of memory. Melatonin has been used for improving sleep in patients with insomnia mainly because it does not cause any hangover or show any addictive potential. However, there is a lack of consistency concerning its therapeutic value (partly because of its short half-life and the small quantities of melatonin used. Thus, attention has been focused either on the development of more potent melatonin analogs with prolonged effects or on the design of slow-release melatonin preparations. A prolonged-release preparation of melatonin 2 mg (Circadin® has been approved for the treatment of primary insomnia in patients aged ≥55 years in the European Union. This prolonged-release preparation of melatonin had no effect on psychomotor functions, memory recall, or driving skills during the night or the next morning relative to placebo

  17. Amplitude of the plasma melatonin nycthemeral rhythms is not associated with the dates of onset and offset of the seasonal ovulatory activity in the Ile-de-France ewe

    Zarazaga Garcés, Luis Ángel; Malpaux, Benoît; Chemineau, Phileppe

    2003-01-01

    We investigated if absolute (nocturnal) or relative (nocturnal/diurnal ratio) plasma melatonin concentrations were associated with the seasonal ovulatory activity in Ile-de-France ewes. Ninety-six and 121 ewes in two different groups of the same flock were used to determine the potential existence of a relationship between melatonin concentrations at the summer and winter solstices, and the dates of onset and offset of the ovulatory activity, respectively. The dates of the first and last ovul...

  18. Analgesic effects of melatonin

    Wilhelmsen, Michael; Amirian, Ilda; Reiter, Russel J;

    2011-01-01

    Melatonin is an endogenous indoleamine, produced mainly by the pineal gland. Melatonin has been proven to have chronobiotic, antioxidant, antihypertensive, anxiolytic and sedative properties. There are also experimental and clinical data supporting an analgesic role of melatonin. In experimental...... has not been clarified. The effects may be linked to G(i) -coupled melatonin receptors, to G(i) -coupled opioid µ-receptors or GABA-B receptors with unknown downstream changes with a consequential reduction in anxiety and pain. Also, the repeated administration of melatonin improves sleep and thereby...... may reduce anxiety, which leads to lower levels of pain. In this paper, we review the current evidence regarding the analgesic properties of melatonin in animals and humans with chronic pain....

  19. Analgesic effects of melatonin

    Wilhelmsen, Michael; Amirian, Ilda; Reiter, Russel J;

    2011-01-01

    Melatonin is an endogenous indoleamine, produced mainly by the pineal gland. Melatonin has been proven to have chronobiotic, antioxidant, antihypertensive, anxiolytic and sedative properties. There are also experimental and clinical data supporting an analgesic role of melatonin. In experimental...... has not been clarified. The effects may be linked to G(i) -coupled melatonin receptors, to G(i) -coupled opioid μ-receptors or GABA-B receptors with unknown downstream changes with a consequential reduction in anxiety and pain. Also, the repeated administration of melatonin improves sleep and thereby...... may reduce anxiety, which leads to lower levels of pain. In this paper, we review the current evidence regarding the analgesic properties of melatonin in animals and humans with chronic pain....

  20. Melatonin and Oral Cavity

    Murat İnanç Cengiz; Seda Cengiz; Hom-Lay Wang

    2012-01-01

    While initially the oral cavity was considered to be mainly a source of various bacteria, their toxins and antigens, recent studies showed that it may also be a location of oxidative stress and periodontal inflammation. Accordingly, this paper focuses on the involvement of melatonin in oxidative stress diseases of oral cavity as well as on potential therapeutic implications of melatonin in dental disorders. Melatonin has immunomodulatory and antioxidant activities, stimulates the proliferatio...

  1. Melatonin Promotes Superovulation in Sika Deer (Cervus nippon

    Liang Wang

    2014-07-01

    Full Text Available In this study, the effects of melatonin (MT on superovulation and reproductive hormones (melatonin, follicle-stimulating hormone (FSH, luteinizing hormone (LH and PRL were investigated in female sika deer. Different doses (40 or 80 mg/animal of melatonin were subcutaneously implanted into deer before the breeding season. Exogenous melatonin administration significantly elevated the serum FSH levels at the time of insemination compared with levels in control animals. During superovulation, the serum LH levels in donor sika deer reached their highest values (7.1 ± 2.04 ng/mL at the point of insemination, compared with the baseline levels (4.98 ± 0.07 ng/mL in control animals. This high level of LH was sustained until the day of embryo recovery. In contrast, the serum levels of PRL in the 80 mg of melatonin-treated group were significantly lower than those of control deer. The average number of corpora lutea in melatonin-treated deer was significantly higher than that of the control (p < 0.05. The average number of embryos in the deer treated with 40 mg of melatonin was higher than that of the control; however, this increase did not reach significant difference (p > 0.05, which may be related to the relatively small sample size. In addition, embryonic development in melatonin-treated groups was delayed.

  2. Secondary Nocturnal Enuresis

    ... NKF Newsroom Contact Us You are here Home » Secondary Nocturnal Enuresis Some children have always wet the ... is important to instill confidence and enhance compliance. Motivation is an important factor for success. Many of ...

  3. Nocturnal panic attacks

    Lopes Fabiana L; Nardi Antonio E; Nascimento Isabella; Valença Alexandre M.; Zin Walter A.

    2002-01-01

    The panic-respiration connection has been presented with increasing evidences in the literature. We report three panic disorder patients with nocturnal panic attacks with prominent respiratory symptoms, the overlapping of the symptoms with the sleep apnea syndrome and a change of the diurnal panic attacks, from spontaneous to situational pattern. The implication of these findings and awareness to the distinct core of the nocturnal panic attacks symptoms may help to differentiate them from sle...

  4. Melatonin and cortisol profiles in late midlife and their association with age-related changes in cognition

    Waller, Katja Linda; Mortensen, Erik Lykke; Avlund, Kirsten; Fagerlund, Birgitte; Lauritzen, Martin; Gammeltoft, Steen; Jennum, Poul

    2016-01-01

    Previous studies have reported an association between circadian disturbances and age-related cognitive impairment. The aim was to study the 24-hour profiles of melatonin and cortisol in relation to cognitive function in middle-aged male subjects. Fifty healthy middle-aged males born in 1953 were recruited from a population-based cohort based on previous cognitive assessments in young adulthood and late midlife. The sample included 24 cognitively high-functioning and 26 cognitively impaired participants. Saliva samples were collected every 4 hours over a 24-hour period and analyzed for cortisol and melatonin levels by immunoassay. All participants exhibited clear circadian rhythms of salivary melatonin and cortisol. Salivary melatonin concentrations had a nocturnal peak at approximately 4 am. The median nocturnal melatonin response at 4 am was significantly lower in the cognitively impaired group than in the high-functioning group (−4.6 pg/mL, 95% CI: −7.84, −1.36, P=0.006). The 24-hour mean melatonin concentration (high-functioning group: 4.80±0.70 pg/mL, vs cognitively impaired group: 4.81±0.76 pg/mL; P>0.05) (or the area under the curve, AUC) was not significantly different between the two groups. Cortisol levels were low during the night, and peaked at approximately 8 am. Median cortisol concentrations were similar at all times, as were the 24-hour mean cortisol concentrations and AUC. To the best of our knowledge, ours is the first study to assess circadian measures (ie, melatonin and cortisol) in healthy middle-aged men with different cognitive trajectories in midlife. We found evidence of altered circadian rhythms with a reduced nocturnal melatonin response at 4 am in men with cognitive impairment. The 24-hour concentration and AUC of melatonin and cortisol were similar in the cognitively high-functioning group and in the cognitively impaired. PMID:26858531

  5. Differential regulation of kiss1 expression by melatonin and gonadal hormones in male and female Syrian hamsters

    Ansel, L; Bolborea, M; Bentsen, A H;

    2010-01-01

    rodents, Kiss1 is expressed in the anteroventral periventricular nucleus (AVPV) and in the arcuate nucleus (ARC). Because both the duration of the nocturnal peak of melatonin and circulating sex steroid levels vary with photoperiod, the aim of this study was to determine whether melatonin and sex steroids...... as compared to LD animals, 2) sex steroid treatment in SD-adapted male and female hamsters increased the number of Kiss1 neurons in the AVPV but decreased it in the ARC, 3) melatonin administration to LD-adapted hamsters decreased Kiss1 mRNA level in both the AVPV and the ARC in intact animals...... Syrian hamster hypothalamus is down-regulated in SD via different mechanisms. In the ARC, melatonin inhibits Kiss1 via a direct effect on the hypothalamus, and this effect is probably sex steroid dependent, whereas in the AVPV, the decrease in Kiss1 expression appears to be secondary to the melatonin...

  6. Variability of plasma melatonin level in pony mares (Equus caballus), comparison with the hybrid: mules and with jennies (Equus asinus).

    Guillaume, Daniel; Zarazaga, Luiz A; Malpaux, Benoît; Chemineau, Philippe

    2006-01-01

    In long-day breeders like horses, the length of nocturnal melatonin secretion is the main messenger of photoperiod. Previous studies have shown that the nocturnal jugular melatonin concentration is lower in horses, than in mules but is unknown in donkeys. The aim of this study was to estimate the inter-animal variability of plasma melatonin concentration in domestic mares and to compare this concentration with those observed in domestic jennies and in their hybrid mules. In the autumn, blood samples were collected at 22 h, 23 h, 0 h and 1 h during 2 nights at 3 weeks intervals, in 110 pony mares, 10 jennies and 6 mules maintained under natural photoperiod. Melatonin was assayed by a validated RIA method. The statistical analysis of the measures was done with a specific unbalanced analysis of variance model. The effect of species and individuals (nested under species) was highly significant. The mean melatonin concentration was 24 pg.mL(-1) in mares and was significantly lower than in jennies and in mules which were 90 pg.mL(-1) and 169 pg.mL(-1) respectively. The melatonin plasma concentration was higher in jennies than in mares. These results suggest that the melatonin concentration is genetically determined. PMID:17169310

  7. The effect of acute exogenous melatonin on P50 suppression in healthy male volunteers stratified for low and high gating levels

    Ucar, Ebru; Lehtinen, Emilia K; Glenthøj, Birte Y;

    2012-01-01

    Sensory gating is frequently found to be disturbed in patients with schizophrenia. In addition, a disruption of the circadian rhythm together with a low nocturnal melatonin output is regularly found in these patients. Since there is some evidence that a brief period of sleep normalizes sensory...... gating in schizophrenia patients, it is conceivable that their disrupted melatonin level may contribute to the deficits in P50 suppression. In this initial study, the effects of acutely administered melatonin on sensory gating in healthy subjects were investigated. In a double-blind placebo......-controlled crossover design, 21 healthy male volunteers were administered melatonin (4 mg) or placebo, after which they were tested in a P50 suppression paradigm. In the group as a whole, melatonin did not affect P50 suppression. However, melatonin increased the P50 ratio in the individuals with high baseline...

  8. Melatonin Protects N2a against Ischemia/Reperfusion Injury through Autophagy Enhancement

    国艳春; 王剑飞; 王忠强; 杨易; 王西明; 段秋红

    2010-01-01

    Researches have shown that melatonin is neuroprotectant in ischemia/reperfusion-mediated injury.Although melatonin is known as an effective antioxidant,the mechanism of the protection cannot be explained merely by antioxidation.This study was devoted to explore other existing mechanisms by investigating whether melatonin protects ischemia/reperfusion-injured neurons through elevating autophagy,since autophagy has been frequently suggested to play a crucial role in neuron survival.To find it out,an ischemia/...

  9. The effect of sleep on nocturnal urine output

    Kamperis, Konstantinos; Hagstrøm, Søren; Rittig, Søren;

    2005-01-01

      Hypothesis / aims of studyAim of this study was to elucidate the impact of sleep on the quantity and quality of the nocturnal urine production in healthy individuals.Our hypothesis was that sleep deprivation is related to excess nocturnal urine production.Study design, materials and methods...... from sleep and the sequence was randomized. During these nights with sleep deprivation, participants were in lying position in a dimly lit room and physical activities, food and fluid intake were not allowed. Smoking was not allowed throughout the entire experimental protocol. Determinations of...... using an enzyme immunoassay. 6-sulfatoxy-melatonin (MEL) was measured in urine using and ELISA assay. Clearances, excretions and fractional excretions were calculated for electrolytes, creatinine, urea, osmoles and solute free water. Comparisons were made between the nights with and without sleep...

  10. Blood glucose and nocturnal blood pressure in African and caucasian men: the SABPA study

    Lammertyn, Leandi; Schutte, Aletta Elisabeth; Schutte, Rudolph

    2011-01-01

    To investigate the relationship between nocturnal blood pressure and chronically elevated blood glucose to determine if these elevated blood glucose concentrations contribute to a non-dipping blood pressure, especially in high-risk groups such as Africans.

  11. Nocturnal continuous glucose monitoring

    Bay, Christiane; Kristensen, Peter Lommer; Pedersen-Bjergaard, Ulrik;

    2013-01-01

    Abstract Background: A reliable method to detect biochemical nocturnal hypoglycemia is highly needed, especially in patients with recurrent severe hypoglycemia. We evaluated reliability of nocturnal continuous glucose monitoring (CGM) in patients with type 1 diabetes at high risk of severe...... from 23:00 to 07:00 h for plasma glucose (PG) measurements (gold standard). Results: Valid data were obtained in 217 nights. The sensitivity of CGM was 65% (95% confidence interval, 53-77%) below 4 mmol/L, 40% (24-56%) below 3 mmol/L, and 17% (0-47%) below 2.2 mmol/L. PG and CGM readings correlated in...

  12. Nocturnal panic attacks

    Lopes Fabiana L.

    2002-01-01

    Full Text Available The panic-respiration connection has been presented with increasing evidences in the literature. We report three panic disorder patients with nocturnal panic attacks with prominent respiratory symptoms, the overlapping of the symptoms with the sleep apnea syndrome and a change of the diurnal panic attacks, from spontaneous to situational pattern. The implication of these findings and awareness to the distinct core of the nocturnal panic attacks symptoms may help to differentiate them from sleep disorders and the search for specific treatment.

  13. Melatonin promotes superovulation in sika deer (Cervus nippon).

    Wang, Liang; Zhuo, Zhi-Yong; Shi, Wen-Qing; Tan, Dun-Xian; Gao, Chao; Tian, Xiu-Zhi; Zhang, Lu; Zhou, Guang-Bin; Zhu, Shi-En; Yun, Peng; Liu, Guo-Shi

    2014-01-01

    In this study, the effects of melatonin (MT) on superovulation and reproductive hormones (melatonin, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and PRL) were investigated in female sika deer. Different doses (40 or 80 mg/animal) of melatonin were subcutaneously implanted into deer before the breeding season. Exogenous melatonin administration significantly elevated the serum FSH levels at the time of insemination compared with levels in control animals. During superovulation, the serum LH levels in donor sika deer reached their highest values (7.1±2.04 ng/mL) at the point of insemination, compared with the baseline levels (4.98±0.07 ng/mL) in control animals. This high level of LH was sustained until the day of embryo recovery. In contrast, the serum levels of PRL in the 80 mg of melatonin-treated group were significantly lower than those of control deer. The average number of corpora lutea in melatonin-treated deer was significantly higher than that of the control (p0.05), which may be related to the relatively small sample size. In addition, embryonic development in melatonin-treated groups was delayed. PMID:25007067

  14. Melatonin-mediated cytoprotection against hyperglycemic injury in Muller cells.

    Tingting Jiang

    Full Text Available Oxidative stress is a contributing factor to the development and progression of diabetic retinopathy, a leading cause of blindness in people at working age worldwide. Recent studies showed that Müller cells play key roles in diabetic retinopathy and produce vascular endothelial growth factor (VEGF that regulates retinal vascular leakage and proliferation. Melatonin is a potent antioxidant capable of protecting variety of retinal cells from oxidative damage. In addition to the pineal gland, the retina produces melatonin. In the current study, we investigated whether melatonin protects against hyperglycemia-induced oxidative injury to Müller cells and explored the potential underlying mechanisms. Our results show that both melatonin membrane receptors, MT1 and MT2, are expressed in cultured primary Müller cells and are upregulated by elevated glucose levels. Both basal and high glucose-induced VEGF production was attenuated by melatonin treatment in a dose-dependent manner. Furthermore, we found that melatonin is a potent activator of Akt in Müller cells. Our findings suggest that in addition to functioning as a direct free radical scavenger, melatonin can elicit cellular signaling pathways that are protective against retinal injury during diabetic retinopathy.

  15. Melatonin suppression by light in humans is maximal when the nasal part of the retina is illuminated

    Visser, E.Kathalijne; Beersma, Domien G.M.; Daan, Serge

    1999-01-01

    This study investigated whether sensitivity of the nocturnal melatonin suppression response to Light depends on the area of the retina exposed. The reason to suspect uneven spatial sensitivity distribution stems from animal work that revealed that retinal ganglion cells projecting to the suprachiasm

  16. Melatonin in Chronic Pain Syndromes.

    Danilov, Andrei; Kurganova, Julia

    2016-06-01

    Melatonin is a neurohormone secreted by epiphysis and extrapineal structures. It performs several functions including chronobiotic, antioxidant, oncostatic, immune modulating, normothermal, and anxiolytic functions. Melatonin affects the cardiovascular system and gastrointestinal tract, participates in reproduction and metabolism, and body mass regulation. Moreover, recent studies have demonstrated melatonin efficacy in relation to pain syndromes. The present paper reviews the studies on melatonin use in fibromyalgia, headaches, irritable bowel syndrome, chronic back pain, and rheumatoid arthritis. The paper discusses the possible mechanisms of melatonin analgesic properties. On one hand, circadian rhythms normalization results in sleep improvement, which is inevitably disordered in chronic pain syndromes, and activation of melatonin adaptive capabilities. On the other hand, there is evidence of melatonin-independent analgesic effect involving melatonin receptors and several neurotransmitter systems. PMID:26984272

  17. Melatonin and cortisol profiles in late midlife and their association with age-related changes in cognition

    Waller, Katja Linda; Mortensen, Erik Lykke; Avlund, Kirsten;

    2016-01-01

    Previous studies have reported an association between circadian disturbances and age-related cognitive impairment. The aim was to study the 24-hour profiles of melatonin and cortisol in relation to cognitive function in middle-aged male subjects. Fifty healthy middle-aged males born in 1953 were...... melatonin levels by immunoassay. All participants exhibited clear circadian rhythms of salivary melatonin and cortisol. Salivary melatonin concentrations had a nocturnal peak at approximately 4 am. The median nocturnal melatonin response at 4 am was significantly lower in the cognitively impaired group than...... in the high-functioning group (-4.6 pg/mL, 95% CI: -7.84, -1.36, P=0.006). The 24-hour mean melatonin concentration (high-functioning group: 4.80±0.70 pg/mL, vs cognitively impaired group: 4.81±0.76 pg/mL; P>0.05) (or the area under the curve, AUC) was not significantly different between the two...

  18. Pathophysiology of nocturnal enuresis

    Rittig, Søren; Kamperis, Konstantinos

    The perception of the pathogenesis of enuresis has undergone marked changes over the past 30 years from a psychiatric/psychological background to a more somatic model where nighttime urine production and bladder capacity are main components together with an arousal dysfunction that prevents the...... important part of enuresis pathogenesis is reduced bladder capacity, either during night-time only or present during daytime also (i.e. reduced MVV on a FV chart). The background behind the reduced nocturnal reservoir function is not fully clarified but may involve CNS regulatory centers, detrusor...... that dysfunction of the intrinsic circadian regulation located in the suprachiasmatic nucleus results in dysfunction of one or more of the brainstem centers involved in AVP secretion, arousal function, bladder control, and blood pressure regulation. Furthermore, nocturnal enuresis has a strong genetic...

  19. Effect of constant temperatures, darkness and light on the secretion of melatonin by pineal explants and retinas in the gecko Christinus marmoratus.

    Moyer, R W; Firth, B T; Kennaway, D J

    1995-03-27

    The effects of temperature and lighting conditions on the secretion of melatonin by the pineal organ of the nocturnal gecko Christinus marmoratus was studied using in vitro perifusion. In a 12L:12D lighting regime, a high-amplitude melatonin rhythm was detectable at a constant temperature of 20 and 30 degrees C but not at 10 or 37 degrees C. There were sustained high levels of melatonin in constant darkness and sustained low levels in constant light. No retinal melatonin was detected using static and perifusion culture techniques. These results show that the pineal organ of C. marmoratus maintains light sensitivity in vitro but does not contain an oscillator coupled to the melatonin synthetic pathway. PMID:7796151

  20. Effect of melatonin on kidney cold ischemic preservation injury

    Aslaner, Arif; Gunal, Omer; Turgut, Hamdi Taner; Celik, Erdal; Yildirim, Umran; Demirci, Rojbin Karakoyun; Gunduz, Umut Riza; Calis, Hasan; Dogan, Sami

    2013-01-01

    Melatonin is a potent free radical scavenger of reactive oxygen species, nitric oxide synthase inhibitor and a well-known antioxidant secreted from pineal gland. This hormone has been reported to protect tissue from oxidative damage. In this study, we aim to investigate the effect of melatonin on kidney cold ischemia time when added to preservation solution. Thirty male Wistar albino rats were divided equally into three groups; Ringer Lactate (RL) solution, University of Wisconsin (UW) solution with and without melatonin. The serum Lactate Dehydrogenase (LDH) activities of the preservation solutions at 2nd, 24th, 36th, and 48th hours were determined. Tissue malondialdehyde (MDA) levels were also measured and a histological examination was performed at 48th hour. Melatonin that added to preservation solution prevented enzyme elevation and decreased lipid peroxidation in preservation solution when compared to the control group (p<0.05). The histological examination revealed that UW solution containing melatonin significantly prevented the kidney from pathological injury (p<0.05). Melatonin added to preservation solutions such as UW solution seemed to protect the tissue preserved effectively from cold ischemic injury for up to 48 hour. PMID:24179573

  1. MT1 and MT2 Melatonin Receptors: A Therapeutic Perspective.

    Liu, Jiabei; Clough, Shannon J; Hutchinson, Anthony J; Adamah-Biassi, Ekue B; Popovska-Gorevski, Marina; Dubocovich, Margarita L

    2016-01-01

    Melatonin, or 5-methoxy-N-acetyltryptamine, is synthesized and released by the pineal gland and locally in the retina following a circadian rhythm, with low levels during the day and elevated levels at night. Melatonin activates two high-affinity G protein-coupled receptors, termed MT1 and MT2, to exert beneficial actions in sleep and circadian abnormality, mood disorders, learning and memory, neuroprotection, drug abuse, and cancer. Progress in understanding the role of melatonin receptors in the modulation of sleep and circadian rhythms has led to the discovery of a novel class of melatonin agonists for treating insomnia, circadian rhythms, mood disorders, and cancer. This review describes the pharmacological properties of a slow-release melatonin preparation (i.e., Circadin®) and synthetic ligands (i.e., agomelatine, ramelteon, tasimelteon), with emphasis on identifying specific therapeutic effects mediated through MT1 and MT2 receptor activation. Discovery of selective ligands targeting the MT1 or the MT2 melatonin receptors may promote the development of novel and more efficacious therapeutic agents. PMID:26514204

  2. Experience with sustained-release melatonin for the treatment of sleep disorders in depression

    Svetlana Vladimirovna Prokhorova

    2015-01-01

    Full Text Available The data available in the literature on the role of melatonin in the regulation of circadian rhythms and sleep disorders in the population and in patients with mental diseases are analyzed. The cause of insomnia may be circadian rhythm disorders due to the age-related decline in the elaboration of the endogenous hormones that are responsible for the quality and duration of sleep, one of which is melatonin.Sustained-release melatonin is a synthetic analogue of the endogenous human pineal hormone melatonin. According to clinical findings, the main proven clinical effects of sustained-release melatonin 2 mg are a reduction in the latency of sleep, improvement of its quality, and lack of daytime sleepiness. The drug causes no dependence on its long use and rebound symptoms (increased insomnia symptoms, positively affects cognitive functions, and lowers nocturnal blood pressure in hypertensive patients.The paper describes a clinical case of a female patient with recurrent depressive disorder, in whom sustained-release melatonin 2 mg has demonstrated high efficacy and good tolerability in the combination therapy of sleep disorders in the pattern of depression.

  3. Light-induced melatonin suppression at night after exposure to different wavelength composition of morning light.

    Kozaki, Tomoaki; Kubokawa, Ayaka; Taketomi, Ryunosuke; Hatae, Keisuke

    2016-03-11

    Bright nocturnal light has been shown to suppress melatonin secretion. However, bright light exposure during the day might reduce light-induced melatonin suppression at night. The human circadian system is sensitive to short wavelength light. This study evaluated the preventive effect of different wavelengths of daytime light on light-induced melatonin suppression at night. Twelve male subjects were exposed to various light conditions (dim, white, and bluish white light) between the hours of 09:00 and 10:30 (daytime light conditions). They were then exposed to light (300lx) again between 01:00 and 02:30 (night-time light exposure). Subjects provided saliva samples before (00:55) and after night-time light exposure (02:30). A two-tailed paired t-test yielded significant decrements in melatonin concentrations after night-time light exposure under daytime dim and white light conditions. No significant differences were found in melatonin concentrations between pre- and post-night-time light exposure with bluish-white light. Present findings suggest that daytime blue light exposure has an acute preventive impact on light-induced melatonin suppression in individuals with a general life rhythm (sleep/wake schedule). These findings may be useful for implementing artificial light environments for humans in, for example, hospitals and underground shopping malls to reduce health risks. PMID:26777427

  4. Evaluation And Comparison Of Serum Melatonin Determination In Normal Individuals And Migraine Patients

    Fooladsaz K

    2004-06-01

    Full Text Available Background: Migraine is a chronic hereditary and relapsing headache. With regard to the prevalence of this ancient disease and its economic complications in country, in this study , nocturnal serum melatonin of migraine patients and control subjects have been evaluated and compared by ELISA kit. Materials and Methods: Fifty migraine patients (mostly women were compared to a control group (mostly men matched according to age. Results: Statistical analysis revealed a decrease in nocturnal serum melatonin levels for migraine patients (32.9 28.4 compared to the control one (75.6 56.8. With using of t-test by ELISA kit showed significant difference (p=0.0064. Conclusion: With regard to this, the pineal gland has the main role in the synchronization of the organism with the environmental conditions and migrainous headaches.

  5. Differential regulation of kiss1 expression by melatonin and gonadal hormones in male and female Syrian hamsters

    Ansel, L; Bolborea, M; Bentsen, A H;

    2010-01-01

    In seasonal breeders, reproduction is synchronized to seasons by day length via the pineal hormone melatonin. Recently, we have demonstrated that Kiss1, a key activator of the reproductive function, is down-regulated in sexually inactive hamsters maintained in inhibitory short days (SDs). In...... rodents, Kiss1 is expressed in the anteroventral periventricular nucleus (AVPV) and in the arcuate nucleus (ARC). Because both the duration of the nocturnal peak of melatonin and circulating sex steroid levels vary with photoperiod, the aim of this study was to determine whether melatonin and sex steroids...... as compared to LD animals, 2) sex steroid treatment in SD-adapted male and female hamsters increased the numberof Kiss1 neurons in the AVPV but decreased it in the ARC, 3) melatonin administration to LD-adapted hamsters decreased Kiss1 mRNA level in both the AVPV and the ARC in intact animals...

  6. Melatonin protection from chronic, low-level ionizing radiation.

    Reiter, Russel J; Korkmaz, Ahmet; Ma, Shuran; Rosales-Corral, Sergio; Tan, Dun-Xian

    2011-12-15

    In the current survey, we summarize the published literature which supports the use of melatonin, an endogenously produced molecule, as a protective agent against chronic, low-level ionizing radiation. Under in vitro conditions, melatonin uniformly was found to protect cellular DNA and plasmid super coiled DNA from ionizing radiation damage due to Cs(137) or X-radiation exposure. Likewise, in an in vivo/in vitro study in which humans were given melatonin orally and then their blood lymphocytes were collected and exposed to Cs(137) ionizing radiation, nuclear DNA from the cells of those individuals who consumed melatonin (and had elevated blood levels) was less damaged than that from control individuals. In in vivo studies as well, melatonin given to animals prevented DNA and lipid damage (including limiting membrane rigidity) and reduced the percentage of animals that died when they had been exposed to Cs(137) or Co(60) radiation. Melatonin's ability to protect macromolecules from the damage inflicted by ionizing radiation likely stems from its high efficacy as a direct free radical scavenger and possibly also due to its ability to stimulate antioxidative enzymes. Melatonin is readily absorbed when taken orally or via any other route. Melatonin's ease of self administration and its virtual absence of toxicity or side effects, even when consumed over very long periods of time, are essential when large populations are exposed to lingering radioactive contamination such as occurs as a result of an inadvertent nuclear accident, an intentional nuclear explosion or the detonation of a radiological dispersion device, i.e., a "dirty" bomb. PMID:22185900

  7. Plasma melatonin in the horse: measurements in natural photoperiod and in acutely extended darkness throughout the year.

    Guerin, M V; Deed, J R; Kennaway, D J; Matthews, C D

    1995-08-01

    Plasma melatonin was measured at the winter and summer solstices and the autumn and spring equinoxes in four mares held under natural conditions at 35 degrees S. At all seasons the onset of the nightly elevated melatonin was coincident with or after the time of sunset and the melatonin offset after the time of sunrise. The duration of elevated melatonin was not different from the duration of natural scotophase for each season, with the duration of elevated melatonin longer in winter than the other seasons. Immediately following each 24 hr sampling two mares were resampled in acutely extended darkness to determine the melatonin profile of the endogenous rhythm of the circadian pacemaker, originating from the suprachiasmatic nuclei (SCN). At each season melatonin secretion commenced earlier and decreased later than that measured under the natural photoperiodic condition, suggesting that the expression of the melatonin rhythm is normally gated by natural environmental light both at dusk and dawn. The interval from the onset of melatonin measured under acutely extended darkness to the time of sunset was greater in the spring/summer than the autumn/winter suggesting a possible alternating signal throughout the year. Thus the mare appears to exhibit a similar interaction between endogenous circadian rhythmic activity and the natural photoperiod as the ewe which may underlie the mechanism for timing reproductive activity through the year. PMID:8609596

  8. Behavioral Treatment for Nocturnal Enuresis

    Friman, Patrick C.; Jones, Kevin M.

    2005-01-01

    Nocturnal enuresis is one of the most prevalent and distressing of all childhood problems. The treatment of nocturnal enuresis has shifted in the past few decades from a strictly psychopathological perspective to a biobehavioral perspective. Although the primary clinical features of this disorder are medical/organic, there is currently strong…

  9. Effect of melatonin administration on subjective sleep quality in chronic obstructive pulmonary disease

    D.M. Nunes

    2008-10-01

    Full Text Available Disturbed sleep is common in chronic obstructive pulmonary disease (COPD. Conventional hypnotics worsen nocturnal hypoxemia and, in severe cases, can lead to respiratory failure. Exogenous melatonin has somnogenic properties in normal subjects and can improve sleep in several clinical conditions. This randomized, double-blind, placebo-controlled study was carried out to determine the effects of melatonin on sleep in COPD. Thirty consecutive patients with moderate to very severe COPD were initially recruited for the study. None of the participants had a history of disease exacerbation 4 weeks prior to the study, obstructive sleep apnea, mental disorders, current use of oral steroids, methylxanthines or hypnotic-sedative medication, nocturnal oxygen therapy, and shift work. Patients received 3 mg melatonin (N = 12 or placebo (N = 13, orally in a single dose, 1 h before bedtime for 21 consecutive days. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI and daytime sleepiness was measured by the Epworth Sleepiness Scale. Pulmonary function and functional exercise level were assessed by spirometry and the 6-min walk test, respectively. Twenty-five patients completed the study protocol and were included in the final analysis. Melatonin treatment significantly improved global PSQI scores (P = 0.012, particularly sleep latency (P = 0.008 and sleep duration (P = 0.046. No differences in daytime sleepiness, lung function and functional exercise level were observed. We conclude that melatonin can improve sleep in COPD. Further long-term studies involving larger number of patients are needed before melatonin can be safely recommended for the management of sleep disturbances in these patients.

  10. Melatonin: Buffering the Immune System

    Juan M. Guerrero

    2013-04-01

    Full Text Available Melatonin modulates a wide range of physiological functions with pleiotropic effects on the immune system. Despite the large number of reports implicating melatonin as an immunomodulatory compound, it still remains unclear how melatonin regulates immunity. While some authors argue that melatonin is an immunostimulant, many studies have also described anti-inflammatory properties. The data reviewed in this paper support the idea of melatonin as an immune buffer, acting as a stimulant under basal or immunosuppressive conditions or as an anti-inflammatory compound in the presence of exacerbated immune responses, such as acute inflammation. The clinical relevance of the multiple functions of melatonin under different immune conditions, such as infection, autoimmunity, vaccination and immunosenescence, is also reviewed.

  11. Endogenous melatonin and oxidatively damaged guanine in DNA

    Poulsen Henrik E

    2009-10-01

    Full Text Available Abstract Background A significant body of literature indicates that melatonin, a hormone primarily produced nocturnally by the pineal gland, is an important scavenger of hydroxyl radicals and other reactive oxygen species. Melatonin may also lower the rate of DNA base damage resulting from hydroxyl radical attack and increase the rate of repair of that damage. This paper reports the results of a study relating the level of overnight melatonin production to the overnight excretion of the two primary urinary metabolites of the repair of oxidatively damaged guanine in DNA. Methods Mother-father-daughter(s families (n = 55 were recruited and provided complete overnight urine samples. Total overnight creatinine-adjusted 6-sulphatoxymelatonin (aMT6s/Cr has been shown to be highly correlated with total overnight melatonin production. Urinary 8-oxo-7,8-dihydro-guanine (8-oxoGua results from the repair of DNA or RNA guanine via the nucleobase excision repair pathway, while urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG may possibly result from the repair of DNA guanine via the nucleotide excision repair pathway. Total overnight urinary levels of 8-oxodG and 8-oxoGua are therefore a measure of total overnight guanine DNA damage. 8-oxodG and 8-oxoGua were measured using a high-performance liquid chromatography-electrospray ionization tandem mass spectrometry assay. The mother, father, and oldest sampled daughter were used for these analyses. Comparisons between the mothers, fathers, and daughters were calculated for aMT6s/Cr, 8-oxodG, and 8-oxoGua. Regression analyses of 8-oxodG and 8-oxoGua on aMT6s/Cr were conducted for mothers, fathers, and daughters separately, adjusting for age and BMI (or weight. Results Among the mothers, age range 42-80, lower melatonin production (as measured by aMT6s/CR was associated with significantly higher levels of 8-oxodG (p Conclusion Low levels of endogenous melatonin production among older individuals may lead to

  12. Pineal and circulating melatonin rhythms in the box turtle, Terrapene carolina triunguis: effect of photoperiod, light pulse, and environmental temperature.

    Vivien-Roels, B; Pévet, P; Claustrat, B

    1988-02-01

    Pineal and circulating melatonin concentrations have been measured throughout the 24-hr cycle in the box turtle, Terrapene carolina triunguis, under different conditions of photoperiod and temperature. An obvious effect of photoperiod on the duration of the night rise of pineal and circulating melatonin is observed; the period of elevated melatonin is 4.30 hr in long photoperiod (18L:6D) and 11.00 hr in short photoperiod (8L:16D). A single pulse of 1 hr illumination beginning 1.30 hr after the onset of darkness, in a 16L:8D cycle, has no effect on pineal or circulating melatonin levels. A clear effect of environmental temperature on the amplitude of the day-night rhythm of melatonin production is observed. A possible role of the pineal of poikilotherms in the transduction of several environmental factors, via the daily pattern of melatonin secretion, is hypothesized. PMID:3366352

  13. The timing of the shrew: continuous melatonin treatment maintains youthful rhythmic activity in aging Crocidura russula.

    Elodie Magnanou

    Full Text Available BACKGROUND: Laboratory conditions nullify the extrinsic factors that determine the wild expected lifespan and release the intrinsic or potential lifespan. Thus, wild animals reared in a laboratory often show an increased lifespan, and consequently an increased senescence phase. Senescence is associated with a broad suite of physiological changes, including a decreased responsiveness of the circadian system. The time-keeping hormone melatonin, an important chemical player in this system, is suspected to have an anti-aging role. The Greater White-toothed shrew Crocidura russula is an ideal study model to address questions related to aging and associated changes in biological functions: its lifespan is short and is substantially increased in captivity; daily and seasonal rhythms, while very marked the first year of life, are dramatically altered during the senescence process which starts during the second year. Here we report on an investigation of the effects of melatonin administration on locomotor activity of aging shrews. METHODOLOGY/PRINCIPAL FINDINGS: 1 The diel fluctuations of melatonin levels in young, adult and aging shrews were quantified in the pineal gland and plasma. In both, a marked diel rhythm (low diurnal concentration; high nocturnal concentration was present in young animals but then decreased in adults, and, as a result of a loss in the nocturnal production, was absent in old animals. 2 Daily locomotor activity rhythm was monitored in pre-senescent animals that had received either a subcutaneous melatonin implant, an empty implant or no implant at all. In non-implanted and sham-implanted shrews, the rhythm was well marked in adults. A marked degradation in both period and amplitude, however, started after the age of 14-16 months. This pattern was considerably delayed in melatonin-implanted shrews who maintained the daily rhythm for significantly longer. CONCLUSIONS: This is the first long term study (>500 days observation of the

  14. Melatonin Receptor Genes in Vertebrates

    Hua Dong Yin

    2013-05-01

    Full Text Available Melatonin receptors are members of the G protein-coupled receptor (GPCR family. Three genes for melatonin receptors have been cloned. The MT1 (or Mel1a or MTNR1A and MT2 (or Mel1b or MTNR1B receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype, Mel1c (or MTNR1C, has been identified in fish, amphibians and birds. Another melatonin related orphan receptor, GPR50, which does not bind melatonin, is found exclusively in mammals. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. This hormone acts systemically in numerous organs. In the brain, it is involved in the regulation of various neural and endocrine processes, and it readjusts the circadian pacemaker, the suprachiasmatic nucleus. This article reviews recent studies of gene organization, expression, evolution and mutations of melatonin receptor genes of vertebrates. Gene polymorphisms reveal that numerous mutations are associated with diseases and disorders. The phylogenetic analysis of receptor genes indicates that GPR50 is an outgroup to all other melatonin receptor sequences. GPR50 may have separated from a melatonin receptor ancestor before the split between MTNR1C and the MTNR1A/B ancestor.

  15. Protecting the Melatonin Rhythm through Circadian Healthy Light Exposure

    Maria Angeles Bonmati-Carrion

    2014-12-01

    Full Text Available Currently, in developed countries, nights are excessively illuminated (light at night, whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD, including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated with an increased incidence of diabetes, obesity, heart disease, cognitive and affective impairment, premature aging and some types of cancer. Knowledge of retinal photoreceptors and the discovery of melanopsin in some ganglion cells demonstrate that light intensity, timing and spectrum must be considered to keep the biological clock properly entrained. Importantly, not all wavelengths of light are equally chronodisrupting. Blue light, which is particularly beneficial during the daytime, seems to be more disruptive at night, and induces the strongest melatonin inhibition. Nocturnal blue light exposure is currently increasing, due to the proliferation of energy-efficient lighting (LEDs and electronic devices. Thus, the development of lighting systems that preserve the melatonin rhythm could reduce the health risks induced by chronodisruption. This review addresses the state of the art regarding the crosstalk between light and the circadian system.

  16. The function of nocturnal transpiration

    Pfautsch, Sebastian; Resco de Dios, Víctor; Loik, Michael; Tissue, David

    2014-05-01

    Nocturnal transpiration is an important source of water loss, accounting for up to 25% of daytime transpiration in some species. Nocturnal water losses cannot be explained under the prevailing 'paradigm' of optimizing carbon gain while minimizing water loss because carbon fixation does not occur at night. Alternative explanations regarding the function and potential evolutionary advantage of nocturnal transpiration have been proposed, such as enhanced nutrient uptake and transport or delivery of O2 to parenchyma cells for respiration. However, recent evidence suggests that the role of nocturnal transpiration in supplementing the overall plant nutrient budget is relatively small, and the O2 hypothesis is difficult to test experimentally. Here, we propose that the main function of nocturnal transpiration (and water transport) is to prevent catastrophic xylem failure by restoring depleted stem 'capacitors' and enhancing early morning CO2 uptake, as stomata 'prepare' for daytime conditions. Nocturnal sap flux was highest in Eucalyptus grandis trees in the field following a heat wave (reaching 47C with VPDs > 8kPa in the daytime) generating maximal daytime water losses compared with cooler and lower VPD periods, indicating the importance of nocturnal stomatal conductance for stem refilling. Moreover, we observed that the time for stomata to respond to light early in the morning (dawn) across 25 different genotypes of E. camaldulensis in a glasshouse was shortest in those genotypes with highest nocturnal stomatal conductance, which was also correlated with higher daytime photosynthesis. This observation is consistent with previous observations that nocturnal stomatal conductance is partially controlled by the clock, which is utilised to anticipate daytime conditions. Data from the literature suggests that eucalypts respond similarly to other C3 species, suggesting that mechanisms regulating night-time transpiration may be universal.

  17. Nocturnal polyuria in monosymptomatic nocturnal enuresis refractory to desmopressin treatment

    Kamperis, Konstantinos; Rittig, Søren; Jørgensen, Kaj Anker;

    2006-01-01

    their nocturnal urine production. The children with nocturnal polyuria excreted larger amounts of sodium and urea at night than nonpolyurics and controls. Solute-free water reabsorption as well as urinary arginine vasopressin and aquaporin-2 excretion were normal in polyurics, and no differences were...... found in atrial natriuretic peptide, angiotensin II, aldosterone, and renin levels. Urinary prostaglandin E2 (PGE2) excretion was significantly higher in polyurics. The nocturnal polyuria in children with dDAVP-resistant nocturnal enuresis seems to be the result of augmented sodium and urea excretion....... The high urinary PGE2 levels found in these children point toward a role for increased prostaglandin synthesis in the pathogenesis of enuresis-related polyuria....

  18. Clinical pharmacokinetics of melatonin

    Harpsøe, Nathja Groth; Andersen, Lars Peter Holst; Gögenur, Ismail;

    2015-01-01

    PURPOSE: The aim of the review was to provide an overview of studies investigating the pharmacokinetics of exogenous melatonin in humans and if possible, to provide recommendations for clinical use. METHODS: The review was conducted in accordance to PRISMA guidelines. A systematic literature search...... was performed in PubMed and Embase databases. The pharmacokinetic variables included maximal plasma/serum concentration (Cmax), time to maximal plasma/serum concentration (Tmax), elimination half-life (T1/2), area-under-the-curve plasma/serum concentrations (AUC), clearance (Cl), volume of...... between 35 (0.005 mg, IV) and 1602 L (4 mg, oral). Bioavailability of oral melatonin ranged from 9 to 33%. Pharmacokinetics was affected by age, caffeine, smoking, oral contraceptives, feeding status, and fluvoxamine. Critically ill patients displayed accelerated absorption and compromised elimination...

  19. Melatonin reduces acute lung injury in endotoxemic rats

    SHANG You; XU San-peng; WU Yan; JIANG Yuan-xu; WU Zhou-yang; YUAN Shi-ying; YAO Shang-long

    2009-01-01

    was reduced in the melatonin + lipopolysaccharide group. The TNF-α level of pulmonary tissue increased significantly in the vehicle + lipopolysaccharide group ((8.7±0.91) pg/mg protein) compared with that in the vehicle + saline group ((4.3±0.62) pg/mg protein, P <0.01). However, the increase of TNF-α level of pulmonary tissue was significantly reduced in the melatonin + lipopolysaccharide group ((5.9±0.56) pg/mg protein, P <0.01). Pulmonary IL-10 levels were elevated markedly in the vehicle + lipopolysaccharide group in contrast to that in the vehicle + saline group, whereas the elevation was augmented in the melatonin + lipopolysaccharide group. The nuclear localization of p65 increased markedly in the vehicle +lipopolysaccharide group and this enhancement of nuclear p65 expression was much less in the melatonin + lipopolysaccharide group.Conclusion Melatonin reduces acute lung injury in endotoxemic rats by attenuating pulmonary inflammation and inhibiting NF-KB activation.

  20. Demonstration of melatonin in amphibia

    Veerdonk, F.C.G. van de

    1967-01-01

    The presence of melatonin in the amphibian epiphysis has been ascertained earlier by several indirect methods, demonstrating the synthesizing enzyme or precursors of the compound. This communication describes the presence of melatonin in amphibian brain in a direct way, using dextran gel chromatogra

  1. Myocardial infarction and nocturnal hypoxaemia

    Penčić Biljana

    2007-01-01

    Full Text Available Introduction: There is an increased risk of cardiovascular morbidity and mortality in patients with nocturnal intermittent hypoxaemia. Objecive. The aim of this study was to evalute the influence of nocturnal hypoxaemia on ventricular arrhythmias and myocardial ischaemia in patients with myocardial infarction (MI. Method. We studied 77 patients (55.8±7.9 years with MI free of complications, chronic pulmonary diseases, abnormal awake blood gases tension. All patients underwent overnight pulse oximetry and 24-hour electrocardiography. Patients were divided into two groups according to nocturnal hypoxaemia. Total number of ventricular premature complex (VPC; maximal VPC/h; incidence of VPC Lown class>2 and occurrence of ST-segment depression were analyzed for nocturnal (10 PM to 6 AM, daytime (6 AM to 22 PM periods and for the entire 24 hours. Results. Both groups were similar in age, gender, standard risk factors, myocardial infarction size and did not differ in VPC during the analyzed periods. The number of nocturnal maximal VPC/h was insignificantly greater in group 1 (with hypoxaemia compared to group 2 (without hypoxaemia, (p=0.084. Maximal VPC/h did not differ significantly either for daytime or for 24 hours among the groups. Nocturnal VPC Lown>2 were significantly more frequent in group 1 (25% vs 0%, p=0.002. The incidence of VPC Lown>2 was similar during the daytime, and during 24 hrs in both groups. Occurrence of ST-segment depression did not differ between groups 1 and 2. Conclusion. Nocturnal hypoxaemia was associated with complex nocturnal ventricular arrhythmias in patients with MI. .

  2. Monosymptomatic nocturnal enuresis

    Bertan Karaboğa

    2012-03-01

    Full Text Available Enuresis Nocturna is the most common urologic problemin childhood. There is not a consensus about terminology.Terminology identified by The International Children’sContinence Society (ICCS is recommended. Bed-wettingat night during sleep (incontinence in children above 5years of age who don’t have congenital or acquired centralnervous system defect is defined as enuresis nocturna.There are two groups monosymptomatic (simpleand non-monosymptomatic (complicated. Monosymptomaticenuresis nocturna (MNE has no symptoms otherthan bed-wetting at night during sleep. Various theoriesconcerning etiology of MNE has been suggested; one ormore of genetic, hormonal, bladder associated and sleepdisorders are stated to play a role. Self-improvement canbe achieved each year by 15% increasing maturity. Underpinning treatment and in addition to this unique treatmentmust be done by considering the factors in the pathophysiology.The success of the treatment and roadmapto be followed must be arrange with child and family. Thepurpose of this eclectic is; evaluation of correct diagnosis,differential diagnosis, patient follow-up and treatment optionsof the cases applicant with nocturnal enuresis basedon the current knowledge of ICCS and Turkey EnuresisTreatment Guide.

  3. Homeobox Genes and Melatonin Synthesis: Regulatory Roles of the Cone-Rod Homeobox Transcription Factor in the Rodent Pineal Gland

    Kristian Rohde; Morten Møller; Martin Fredensborg Rath

    2014-01-01

    Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processe...

  4. In the Heat of the Night: Thermo-TRPV Channels in the Salmonid Pineal Photoreceptors and Modulation of Melatonin Secretion.

    Nisembaum, Laura Gabriela; Besseau, Laurence; Paulin, Charles-Hubert; Charpantier, Alice; Martin, Patrick; Magnanou, Elodie; Fuentès, Michael; Delgado, Maria-Jesus; Falcón, Jack

    2015-12-01

    Photoperiod plays an essential role in the synchronization of metabolism, physiology, and behavior to the cyclic variations of the environment. In vertebrates, information is relayed by the pineal cells and translated into the nocturnal production of melatonin. The duration of this signal corresponds to the duration of the night. In fish, the pinealocytes are true photoreceptors in which the amplitude of the nocturnal surge is modulated by temperature in a species-dependent manner. Thus, the daily and annual variations in the amplitude and duration of the nocturnal melatonin signal provide information on daily and calendar time. Both light and temperature act on the activity of the penultimate enzyme in the melatonin biosynthesis pathway, the arylalkylamine N-acetyltransferase (serotonin → N-acetylserotonin). Although the mechanisms of the light/dark regulation of melatonin secretion are quite well understood, those of temperature remain unelucidated. More generally, the mechanisms of thermoreception are unknown in ectotherms. Here we provide the first evidence that two thermotransient receptor potential (TRP) channels, TRPV1 and TRPV4, are expressed in the pineal photoreceptor cells of a teleost fish, in which they modulate melatonin secretion in vitro. The effects are temperature dependent, at least for TRPV1. Our data support the idea that the pineal of fish is involved in thermoregulation and that the pineal photoreceptors are also thermoreceptors. In other nervous and nonnervous tissues, TRPV1 and TRPV4 display a ubiquitous but quantitatively variable distribution. These results are a fundamental step in the elucidation of the mechanisms of temperature transduction in fish. PMID:26389691

  5. Methylphenidate Ameliorates Depressive Comorbidity in ADHD Children without any Modification on Differences in Serum Melatonin Concentration between ADHD Subtypes

    Isabel Cubero-Millán

    2014-09-01

    Full Text Available The vast majority of Attention-deficit/hyperactivity disorder (ADHD patients have other associated pathologies, with depressive symptoms as one of the most prevalent. Among the mediators that may participate in ADHD, melatonin is thought to regulate circadian rhythms, neurological function and stress response. To determine (1 the serum baseline daily variations and nocturnal excretion of melatonin in ADHD subtypes and (2 the effect of chronic administration of methylphenidate, as well as the effects on symptomatology, 136 children with ADHD (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision: DSM-IV-TR criteria were divided into subgroups using the “Children’s Depression Inventory” (CDI. Blood samples were drawn at 20:00 and 09:00 h, and urine was collected between 21:00 and 09:00 h, at inclusion and after 4.61 ± 2.29 months of treatment. Melatonin and its urine metabolite were measured by radioimmunoassay RIA. Factorial analysis was performed using STATA 12.0. Melatonin was higher predominantly in hyperactive-impulsive/conduct disordered children (PHI/CD of the ADHD subtype, without the influence of comorbid depressive symptoms. Methylphenidate ameliorated this comorbidity without induction of any changes in the serum melatonin profile, but treatment with it was associated with a decrease in 6-s-melatonin excretion in both ADHD subtypes. Conclusions: In untreated children, partial homeostatic restoration of disrupted neuroendocrine equilibrium most likely led to an increased serum melatonin in PHI/CD children. A differential cerebral melatonin metabolization after methylphenidate may underlie some of the clinical benefit.

  6. Multi-Modal Treatment of Nocturnal Enuresis.

    Mohr, Caroline; Sharpley, Christopher F.

    1988-01-01

    The article reports a multimodal treatment of nocturnal enuresis and anxious behavior in a mildly mentally retarded woman. Behavioral treatment and removal of caffeine from the subject's diet eliminated both nocturnal enuresis and anxious behavior. (Author/DB)

  7. Novel non-indolic melatonin receptor agonists differentially entrain endogenous melatonin rhythm and increase its amplitude

    Drijfhout, W.J; de Vries, J.B; Homan, E.J; Brons, H.F; Copinga, S; Gruppen, G; Beresford, I.J M; Hagan, R.M; Grol, Cor; Westerink, B.H.C.

    1999-01-01

    In this study we have examined the ability of melatonin and four synthetic melatonin receptor agonists to entrain endogenous melatonin secretion in rats, free running in constant darkness. The circadian melatonin profile was measured by trans-pineal microdialysis, which not only reveals the time of

  8. Regularly scheduled, day-time, slow-onset 60 Hz electric and magnetic field exposure does not depress serum melatonin concentration in nonhuman primates

    Rogers, W.R.; Smith, H.D.; Orr, J.L. [Southwest Research Inst., San Antonio, TX (United States); Reiter, R.J.; Barlow-Walden, L. [Univ. of Texas Health Science Center, San Antonio, TX (United States)

    1995-12-31

    Experiments conducted with laboratory rodents indicate that exposure to 60 Hz electric fields or magnetic fields can suppress nocturnal melatonin concentrations in pineal gland and blood. In three experiments employing three field-exposed and three sham-exposed nonhuman primates, each implanted with an indwelling venous cannula to allow repeated blood sampling, the authors studied the effects of either 6 kV/m and 50 {micro}T (0.5 G) or 30 kV/m and 100 {micro}T (1.0 G) on serum melatonin patterns. The fields were ramped on and off slowly, so that no transients occurred. Extensive quality control for the melatonin assay, computerized control and monitoring of field intensities, and consistent exposure protocols were used. No changes in nocturnal serum melatonin concentration resulted from 6 weeks of day-time exposure with slow field onset/offset and a highly regular exposure protocol. These results indicate that, under the conditions tested, day-time exposure to 60 Hz electric and magnetic fields in combination does not result in melatonin suppression in primates.

  9. Utility of melatonin to treat surgical stress after major vascular surgery - a safety study

    Kücükakin, Bülent; Lykkesfeldt, Jens; Nielsen, Hans Jørgen;

    2008-01-01

    Surgery for abdominal aortic aneurysm is associated with elevated oxidative stress. As an antioxidant in animal and human studies, melatonin has the potential of ameliorating some of this oxidative stress, but melatonin has never been administered to adults during surgery for the purpose of...... reducing oxidative damage. The aim of this pilot study was to evaluate the safety of various doses of melatonin administered during or after surgery and to monitor the changes in biomarkers of oxidative stress and inflammation during the pre-, intra- and postoperative period. Six patients undergoing aortic......) were also measured for four days after surgery. Melatonin administration did not change hemodynamic parameters (mean arterial pressure or pulse rate) during surgery (P=0.499 and 0.149, respectively), but oxidative stress parameters (MDA and AA) decreased significantly (P=0.014 and 0.001, respectively...

  10. Evidence for a seasonal variation in the ability of exogenous melatonin to suppress prolactin secretion in the mare.

    Fitzgerald, B P; Davison, L A; McManus, C J

    2000-05-01

    In seasonally breeding species photoperiodic information is thought to be conveyed to the reproductive and prolactin axis via changes in circulating concentrations of melatonin. For some species, a constant melatonin stimulus is perceived as a short day, whereas in others no photoperiodic information is provided. In the mare, a preliminary study demonstrated that constant administration of melatonin did not modify prolactin secretion, suggesting that this treatment regimen failed to provide photoperiodic information. To further investigate this proposal and to investigate an alternative explanation, namely a seasonal variation in response to melatonin, 4 experiments were performed. In experiments 1-3, the effects of constant administration of melatonin on prolactin secretion were investigated. In each study the time of treatment initiation varied beginning before the summer solstice, (May 9; Exp. 1), at the autumnal equinox (Sept. 21; Exp. 2) or the winter solstice (Dec. 21; Exp. 3). In Experiment 4, melatonin was administered as a timed daily injection (5 PM) for 6 months, beginning at the summer solstice (June 21). Constantly elevated physiological concentrations of melatonin (expts. 1-3) and an extended nighttime elevation of melatonin (exp. 4) suppressed prolactin concentrations only during the spring and early summer months (April-August). At other times during the year prolactin concentrations were similar to untreated mares. In the presence of a continuous melatonin implant the circannual rhythm of prolactin secretion was not disturbed. The results suggest that the prolactin axis of the mare is sensitive to an inhibitory melatonin signal during a restricted period of time and that at other times is refractory to this signal. PMID:10869858

  11. Signal transduction and regulation of melatonin synthesis in bovine pinealocytes: impact of adrenergic, peptidergic and cholinergic stimuli.

    Schomerus, Christof; Laedtke, Elke; Olcese, James; Weller, Joan L; Klein, David C; Korf, Horst-Werner

    2002-09-01

    Limited studies of the regulation of pineal melatonin biosynthesis in ungulates indicate that it differs considerably from that in rodents. Here we have investigated several signal transduction cascades and their impact on melatonin synthesis in bovine pinealocytes. Norepinephrine increased the intracellular calcium ion concentration ([Ca2+]i) via alpha(1)-adrenergic receptors. Activation of beta-adrenergic receptors enhanced cAMP accumulation and rapidly elevated arylalkylamine N-acetyltransferase (AANAT) activity and melatonin secretion. The beta-adrenergically evoked increases in AANAT activity were potentiated by alpha(1)-adrenergic stimulation, but this was not seen with cAMP or melatonin production. PACAP treatment caused small increases in cAMP, AANAT activity and melatonin biosynthesis, apparently in a subpopulation of cells. VIP and glutamate did not influence any of these parameters. Activation of nicotinic and muscarinic acetylcholine receptors increased [Ca2+]i, but did not alter cAMP levels, AANAT activity or melatonin production. Our study reveals that discrete differences in pineal signal transduction exist between the cow and rodent, and emphasizes the potential importance that the analysis of ungulate pinealocytes may play in understanding regulation of pineal melatonin biosynthesis in primates and man, whose melatonin-generating system appears to be more similar to that in ungulates than to that in rodents. PMID:12195298

  12. Melatonin inhibits the migration of human lung adenocarcinoma A549 cell lines involving JNK/MAPK pathway.

    Qiaoyun Zhou

    Full Text Available OBJECTIVE: Melatonin, an indolamine produced and secreted predominately by the pineal gland, exhibits a variety of physiological functions, possesses antioxidant and antitumor properties. But, the mechanisms for the anti-cancer effects are unknown. The present study explored the effects of melatonin on the migration of human lung adenocarcinoma A549 cells and its mechanism. METHODS: MTT assay was employed to measure the viability of A549 cells treated with different concentrations of melatonin. The effect of melatonin on the migration of A549 cells was analyzed by wound healing assay. Occludin location was observed by immunofluorescence. The expression of occludin, osteopontin (OPN, myosin light chain kinase (MLCK and phosphorylation of myosin light chain (MLC, JNK were detected by western blots. RESULTS: After A549 cells were treated with melatonin, the viability and migration of the cells were inhibited significantly. The relative migration rate of A549 cells treated with melatonin was only about 20% at 24 h. The expression level of OPN, MLCK and phosphorylation of MLC of A549 cells were reduced, while the expression of occludin was conversely elevated, and occludin located on the cell surface was obviously increased. The phosphorylation status of JNK in A549 cells was also reduced when cells were treated by melatonin. CONCLUSIONS: Melatonin significantly inhibits the migration of A549 cells, and this may be associated with the down-regulation of the expression of OPN, MLCK, phosphorylation of MLC, and up-regulation of the expression of occludin involving JNK/MAPK pathway.

  13. Melatonin and Sleep-Wake Rhythms before and after Ocular Lens Replacement in Elderly Humans.

    Giménez, Marina; Beersma, Domien; Daan, Serge; Pol, Bert van der; Kanis, Martijn; van Norren, Dick; Gordijn, Marijke

    2016-01-01

    Light of short wavelengths has been shown to play a key role in non-image forming responses. Due to aging, the ocular lens becomes more yellow reducing the transmission of short wavelengths in the elderly. In the present study, we make use of cataract surgery to investigate the effects of a relative increase of short wavelength transmission on melatonin- and sleep-wake rhythms (N = 14). We observed, on average, a delay of the sleep-wake and the nocturnal melatonin rhythms after cataract surgery. This delay is tentatively attributed to a relatively large increase of light transmittance in the evening hours more than an increase of the already relatively high light intensities found in the daytime. The later phase that we observed after cataract surgery (clear lens) as compared to the earlier phase observed before cataract (yellowish lens) is in agreement with the general later phase reported in the young (clear lens) population. PMID:26891336

  14. Melatonin and Sleep-Wake Rhythms before and after Ocular Lens Replacement in Elderly Humans

    Marina Giménez

    2016-02-01

    Full Text Available Light of short wavelengths has been shown to play a key role in non-image forming responses. Due to aging, the ocular lens becomes more yellow reducing the transmission of short wavelengths in the elderly. In the present study, we make use of cataract surgery to investigate the effects of a relative increase of short wavelength transmission on melatonin- and sleep-wake rhythms (N = 14. We observed, on average, a delay of the sleep-wake and the nocturnal melatonin rhythms after cataract surgery. This delay is tentatively attributed to a relatively large increase of light transmittance in the evening hours more than an increase of the already relatively high light intensities found in the daytime. The later phase that we observed after cataract surgery (clear lens as compared to the earlier phase observed before cataract (yellowish lens is in agreement with the general later phase reported in the young (clear lens population.

  15. One molecule, many derivatives: a never-ending interaction of melatonin with reactive oxygen and nitrogen species?

    Tan, Dun-Xian; Manchester, Lucien C; Terron, Maria P; Flores, Luis J; Reiter, Russel J

    2007-01-01

    reaction makes melatonin highly effective, even at low concentrations, in protecting organisms from oxidative stress. In accordance with its protective function, substantial amounts of melatonin are found in tissues and organs which are frequently exposed to the hostile environmental insults such as the gut and skin or organs which have high oxygen consumption such as the brain. In addition, melatonin production may be upregulated by low intensity stressors such as dietary restriction in rats and exercise in humans. Intensive oxidative stress results in a rapid drop of circulating melatonin levels. This melatonin decline is not related to its reduced synthesis but to its rapid consumption, i.e. circulating melatonin is rapidly metabolized by interaction with ROS/RNS induced by stress. Rapid melatonin consumption during elevated stress may serve as a protective mechanism of organisms in which melatonin is used as a first-line defensive molecule against oxidative damage. The oxidative status of organisms modifies melatonin metabolism. It has been reported that the higher the oxidative state, the more AFMK is produced. The ratio of AFMK and another melatonin metabolite, cyclic 3-hydroxymelatonin, may serve as an indicator of the level of oxidative stress in organisms. PMID:17198536

  16. Melatonin in pathogenesis and therapy of cancer

    Ravindra T

    2006-12-01

    Full Text Available Melatonin is a neuroendocrine hormone secreted by the pineal gland to transduce the body′s circadian rhythms. An internal 24 hour time keeping system (biological clock regulated by melatonin, controls the sleep-wake cycle. Melatonin production is a highly conserved evolutionary phenomenon. The indole hormone is synthesized in the pinealocytes derived from photoreceptors. Altered patterns and/or levels of melatonin secretion have been reported to coincide with sleep disorders, jetlag, depression, stress, reproductive activities, some forms of cancer and immunological disorders. Lately, the physiological and pathological role of melatonin has become a priority area of investigation, particularly in breast cancer, melanoma, colon cancer, lung cancer and leukemia. According to the ′melatonin hypothesis′ of cancer, the exposure to light at night (LAN and anthropogenic electric and magnetic fields (EMFs is related to the increased incidence of breast cancer and childhood leukaemia via melatonin disruption. Melatonin′s hypothermic, antioxidant and free radical scavenging properties, attribute it to an immunomodulator and an oncostatic agent as well. Many clinical studies have envisaged the potential therapeutic role of melatonin in various pathophysiological disorders, particularly cancer. A substantial reduction in risk of death and low adverse effects were reported from various randomized controlled trials of melatonin treatment in cancer patients. This review summarizes the physiological significance of melatonin and its potential role in cancer therapy. Furthermore, the article focuses on melatonin hypothesis to represent the cause-effect relationship of the three aspects: EMF, LAN and cancer.

  17. Mitochondrial and metabolic dysfunction in renal convoluted tubules of obese mice: protective role of melatonin.

    Alessandra Stacchiotti

    Full Text Available Obesity is a common and complex health problem, which impacts crucial organs; it is also considered an independent risk factor for chronic kidney disease. Few studies have analyzed the consequence of obesity in the renal proximal convoluted tubules, which are the major tubules involved in reabsorptive processes. For optimal performance of the kidney, energy is primarily provided by mitochondria. Melatonin, an indoleamine and antioxidant, has been identified in mitochondria, and there is considerable evidence regarding its essential role in the prevention of oxidative mitochondrial damage. In this study we evaluated the mechanism(s of mitochondrial alterations in an animal model of obesity (ob/ob mice and describe the beneficial effects of melatonin treatment on mitochondrial morphology and dynamics as influenced by mitofusin-2 and the intrinsic apoptotic cascade. Melatonin dissolved in 1% ethanol was added to the drinking water from postnatal week 5-13; the calculated dose of melatonin intake was 100 mg/kg body weight/day. Compared to control mice, obesity-related morphological alterations were apparent in the proximal tubules which contained round mitochondria with irregular, short cristae and cells with elevated apoptotic index. Melatonin supplementation in obese mice changed mitochondria shape and cristae organization of proximal tubules, enhanced mitofusin-2 expression, which in turn modulated the progression of the mitochondria-driven intrinsic apoptotic pathway. These changes possibly aid in reducing renal failure. The melatonin-mediated changes indicate its potential protective use against renal morphological damage and dysfunction associated with obesity and metabolic disease.

  18. Protective effects of thymoquinone and melatonin on intestinal ischemia–reperfusion injury

    Ufuk Tas

    2015-01-01

    Full Text Available Background/Aim: In the present study, we aimed to compare the potential protective effects of thymoquinone and melatonin by using equivalent dose, on oxidative stress-induced ischemia–reperfusion (IR injury in the intestinal tissue of rats. Materials and Methods: The study was performed using 32 male Wistar–Albino rats (weighing 180–200 g randomly divided into four groups: Group I, sham group; Group II, IR group; Group III, IR with melatonin group; and Group IV, IR with thymoquinone group. After laparotomy, ischemia and reperfusion were performed for 60 and 120 min, respectively, on all the groups. Intestinal tissue sections were stained using routine histological methods and examined under the light microscope. In addition, the sections were immunohistochemically stained using the TUNEL method for determination of apoptosis. Superoxide dismutase (SOD activity, glutathione peroxidase (GSH-Px activity, and malondialdehyde (MDA levels in the intestinal tissue were also measured. Results: The IR group had significantly elevated tissue SOD activity, GSH-Px activity, and MDA levels compared with the sham group. Administration of thymoquinone and melatonin efficiently reduced these increases. Statistically significant number of apoptotic cells was observed in the intestinal tissue of IR group rats compared with the sham group. Treatment with thymoquinone and melatonin markedly reduced the number of apoptotic cells. Conclusion: The effects of melatonin and thymoquinone on IR-induced oxidative stress in rat intestines were similar. Our findings suggest that melatonin and thymoquinone protect against IR-induced injury to intestinal tissues.

  19. The Safety of Melatonin in Humans

    Andersen, Lars Peter Holst; Gögenur, Ismail; Rosenberg, Jacob;

    2016-01-01

    Exogenous melatonin has been investigated as treatment for a number of medical and surgical diseases, demonstrating encouraging results. The aim of this review was to present and evaluate the literature concerning the possible adverse effects and safety of exogenous melatonin in humans. Furthermore......, we provide recommendations concerning the possible risks of melatonin use in specific patient groups. In general, animal and human studies documented that short-term use of melatonin is safe, even in extreme doses. Only mild adverse effects, such as dizziness, headache, nausea and sleepiness have...... been reported. No studies have indicated that exogenous melatonin should induce any serious adverse effects. Similarly, randomized clinical studies indicate that long-term melatonin treatment causes only mild adverse effects comparable to placebo. Long-term safety of melatonin in children and...

  20. Melatonin Inhibits GnRH-1, GnRH-3 and GnRH Receptor Expression in the Brain of the European Sea Bass, Dicentrarchus labrax

    José Antonio Muñoz-Cueto

    2013-04-01

    Full Text Available Several evidences supported the existence of melatonin effects on reproductive system in fish. In order to investigate whether melatonin is involved in the modulation of GnRH systems in the European sea bass, we have injected melatonin (0.5 µg/g body mass in male specimens. The brain mRNA transcript levels of the three GnRH forms and the five GnRH receptors present in this species were determined by real time quantitative PCR. Our findings revealed day–night variations in the brain expression of GnRH-1, GnRH-3 and several GnRH receptors (dlGnRHR-II-1c, -2a, which exhibited higher transcript levels at mid-light compared to mid-dark phase of the photocycle. Moreover, an inhibitory effect of melatonin on the nocturnal expression of GnRH-1, GnRH-3, and GnRH receptors subtypes 1c, 2a and 2b was also demonstrated. Interestingly, the inhibitory effect of melatonin affected the expression of hypophysiotrophic GnRH forms and GnRH receptors that exhibit day–night fluctuations, suggesting that exogenous melatonin reinforce physiological mechanisms already established. These interactions between melatoninergic and GnRH systems could be mediating photoperiod effects on reproductive and other rhythmic physiological events in the European sea bass.

  1. Impact of different colours of artificial light at night on melatonin rhythm and gene expression of gonadotropins in European perch.

    Brüning, Anika; Hölker, Franz; Franke, Steffen; Kleiner, Wibke; Kloas, Werner

    2016-02-01

    The distribution and intensity of artificial light at night, commonly referred to as light pollution, is consequently rising and progressively also ecological implications come to light. Low intensity light is known to suppress nocturnal melatonin production in several fish species. This study aims to examine the least suppressive light colour for melatonin excreted into the holding water and the influence of different light qualities and quantities in the night on gene expression of gonadotropins in fish. European perch (Perca fluviatilis) were exposed to light of different wavelengths during the night (blue, green, and red). Melatonin concentrations were measured from water samples every 3h during a 24h period. Gene expression of gonadotropins was measured in perch exposed to different light colours and was additionally examined for perch subjected to different intensities of white light (0 lx, 1 lx, 10 lx, 100 lx) during the night. All different light colours caused a significant drop of melatonin concentration; however, blue light was least suppressive. Gene expression of gonadotropins was not influenced by nocturnal light of different light colours, but in female perch gonadotropin expression was significantly reduced by white light already at the lowest level (1 lx). We conclude that artificial light with shorter wavelengths at night is less effective in disturbing biological rhythms of perch than longer wavelengths, coinciding with the light situation in freshwater habitats inhabited by perch. Different light colours in the night showed no significant effect on gonadotropin expression, but white light in the night can disturb reproductive traits already at very low light intensities. These findings indicate that light pollution has not only the potential to disturb the melatonin cycle but also the reproductive rhythm and may therefore have implications on whole species communities. PMID:26584071

  2. Melatonin Anticancer Effects: Review

    Luigi Di Bella

    2013-01-01

    Full Text Available Melatonin (N-acetyl-5-methoxytryptamine, MLT, the main hormone produced by the pineal gland, not only regulates circadian rhythm, but also has antioxidant, anti-ageing and immunomodulatory properties. MLT plays an important role in blood composition, medullary dynamics, platelet genesis, vessel endothelia, and in platelet aggregation, leukocyte formula regulation and hemoglobin synthesis. Its significant atoxic, apoptotic, oncostatic, angiogenetic, differentiating and antiproliferative properties against all solid and liquid tumors have also been documented. Thanks, in fact, to its considerable functional versatility, MLT can exert both direct and indirect anticancer effects in factorial synergy with other differentiating, antiproliferative, immunomodulating and trophic molecules that form part of the anticancer treatment formulated by Luigi Di Bella (Di Bella Method, DBM: somatostatin, retinoids, ascorbic acid, vitamin D3, prolactin inhibitors, chondroitin-sulfate. The interaction between MLT and the DBM molecules counters the multiple processes that characterize the neoplastic phenotype (induction, promotion, progression and/or dissemination, tumoral mutation. All these particular characteristics suggest the use of MLT in oncological diseases.

  3. 'Melatonin isomer' in wine is not an isomer of the melatonin but tryptophan-ethylester.

    Gardana, Claudio; Iriti, Marcello; Stuknytė, Milda; De Noni, Ivano; Simonetti, Paolo

    2014-11-01

    Melatonin is a neurohormone, chronobiotic, and antioxidant compound found in wine and deriving directly from grapes and/or synthesized by yeast during alcoholic fermentation. In addition, a melatonin isomer has been detected in different foods, wine among them. The special interest for melatonin isomer related to the fact that it was found in greater quantities than melatonin and probably shares some of its biological properties. Despite this, its chemical structure has not yet been defined; although some researchers hypothesize, it could be melatonin with the ethylacetamide group shifted into position N1. Thus, the aim of our study was to identify the structures of the melatonin isomer. For this purpose, melatonin and melatonin isomer in Syrah wine were separated chromatographically by a sub-2 μm particle column and detected by tandem mass spectrometry. The sample was then purified and concentrated by solid-phase extraction, hydrolyzed with alkali or esterase, and substrates and products quantified by UPLC-MS/MS. Moreover, melatonin, melatonin isomer, and their product ions were evaluated by high-resolution mass spectrometry. The amount of melatonin isomer and melatonin in the wine was 84 ± 4 and 3 ± 0 ng/mL, respectively. In the solutions, containing diluted alkali or esterase, melatonin isomer was hydrolyzed in about 8 min. Correspondingly, tryptophan was detected, and its amount increased and reached the maximum concentration in about 8 min. Melatonin concentration was not affected by diluted alkali or esterase. The fragmentation pattern of melatonin isomer was different from that of melatonin but comparable to that of tryptophan-ethylester. Finally, the so-called melatonin isomer identity was verified by cochromatography with authentic standard of tryptophan-ethylester. PMID:25251161

  4. Nocturnal Enuresis and its Impact on Growth

    AmirAli Ghahramani; Mahdi Basirymoghadam; Mohammad Ghahramani

    2008-01-01

    Objective: Nocturnal enuresis is a common developmental-behavioral problem in children. The present study was conducted to estimate the prevalence of primary nocturnal enuresis and to determine its impact on physical growth of the first grade elementary school children. Material & Methods: This is a cross-sectional study carried out on 350 first-grade children (6 to 6.5 yr old) elementary schools in Gonabad through random stratified sampling. All children had primary nocturnal enuresis. A que...

  5. Management of nocturnal enuresis - myths and facts.

    Sinha, Rajiv; Raut, Sumantra

    2016-07-01

    Nocturnal enuresis often causes considerable distress or functional impairment to patient and their parents necessitating a multidisciplinary approach from paediatrician, paediatric nephrologist, urologists and psychiatrist. Mechanisms of monosymptomatic nocturnal enuresis are mainly nocturnal polyuria, bladder overactivity and failure to awaken from sleep in response to bladder sensations. Goal oriented and etiology wise treatment includes simple behavioral intervention, conditioning alarm regimen and pharmacotherapy with desmopressin, imipramine and anticholinergic drugs. Symptoms often recurs requiring change over or combination of different modes of treatment. PMID:27458562

  6. Examination of the melatonin hypothesis in women exposed at night to EMF or bright light.

    Graham, C; Cook, M R; Gerkovich, M M; Sastre, A

    2001-05-01

    It has been hypothesized that the increased incidence of breast cancer in industrial societies is related to greater exposure to power-frequency electric and magnetic fields (EMF) and/or the presence of high levels of light at night (LAN). EMF and LAN are said to reduce circulating levels of the hormone melatonin which, in turn, allows estrogen levels to rise and stimulate the turnover of breast epithelial stem cells and increase the risk for malignant transformation. Three laboratory-based studies, in which a total of 53 healthy young women were exposed at night to EMF or to LAN under controlled exposure conditions, were performed to determine whether such exposures reduce melatonin and are associated with further alterations in estrogen. All-night exposure to industrial-strength magnetic fields (60 Hz, 28.3 microT) had no effect on the blood levels of melatonin or estradiol. In contrast, nocturnal melatonin levels were profoundly suppressed, and the time of peak concentration was significantly delayed in women exposed to LAN, regardless of whether they were in the follicular or luteal phase of the menstrual cycle. These changes, however, were not associated with alterations in point-for-point matching measures of estradiol. Women who chronically secrete high or low amounts of melatonin each night (area-under-curve range: 86-1,296 pg/mL) also did not differ in their blood levels of estradiol. Taken together, these results are consistent with a growing body of evidence which generally suggests that environmental EMF exposure has little or no effect on the parameters measured in this report. PMID:11401762

  7. Melatonin use in sleep disorders

    Chung, KF

    1997-01-01

    Melatonin is a widely publicized 'magical drug'. Claims of its use include regulation of sleep, circadian rhythm, mood, immune system and reproduction, anti-aging, protection against cancer, and treatment of AIDS. This article reviews the evidence of its use in sleep disorders. Its possible indications and adverse effects are discussed.

  8. Melatonin for chronic whiplash syndrome with delayed melatonin onset randomised, placebo-controlled trial

    Wieringen, S. van; Jansen, T.; Smits, M.G.; Nagtegaal, J.E.; Coenen, A.M.L.

    2001-01-01

    Objective: To assess the influence of melatonin in patients with chronic whiplash syndrome and delayed melatonin onset. Design: Randomised, double-blind, placebo-controlled, parallel-group trial. One-week baseline was followed by a 4-week treatment period with either melatonin or placebo. In the ba

  9. Sleep and psychological disturbance in nocturnal asthma

    Stores, G; Ellis, A.; Wiggs, L.; Crawford, C.; Thomson, A.

    1998-01-01

    Subjective and objective sleep disturbance was studied in children with nocturnal asthma. Relations between such disturbance and daytime psychological function were also explored, including possible changes in learning and behaviour associated with improvements in nocturnal asthma and sleep. Assessments included home polysomnography, parental questionnaires concerning sleep disturbance, behaviour, and mood and cognitive testing. Compared with matched controls, children with ...

  10. Melatonin improves sleep quality in hemodialysis patients

    Edalat-Nejad, M.; Haqhverdi, F.; Hossein-Tabar, T.; Ahmadian, M.

    2013-01-01

    Disturbed sleep is common in end-stage renal disease (ESRD). Exogenous melatonin has somniferous properties in normal subjects and can improve sleep quality (SQ) in several clinical conditions. Recent studies have shown that melatonin may play a role in improving sleep in patients undergoing dialysis. The goal of the present study was to assess the effect of exogenous melatonin administration on SQ improvement in daytime hemodialysis patients. Lipid profile and the required dose of erythropoi...

  11. Effectiveness of Melatonin, as a Radiation Damage-Mitigating Drug in Modulating Liver Biochemical disorders in γ-Irradiated Rats

    Melatonin has an anti per oxidative effect on several tissues as well as a scavenger effect on reactive oxygen species (ROS). Whilst radiation-hazards due to free radical generation, present enormous challenges for biological and medical safety. Therefore, rats were classified into four groups; control (n= 8), (received 0.5 ml of alcoholic saline as a vehicle for 5 days). Melatonin-treated rats received 10 mg/ kg body wt, for 5 days (given to the animals in the morning via stomach tube). gamma-irradiated rats received 0.5 ml of the melatonin vehicle followed by one shot dose of 3 Gy gamma-rays. Each of these groups was compared with a further group, which-received melatonin for 5 days after 3 Gy gamma-irradiation exposure. The results revealed that all considered biochemical parameters were not changed significantly in melatonin-treated group as compared with control one. In the liver tissue of the gamma-irradiated animals (3 Gy), the oxidative stress markers malondialdehyde (MDA) and protein carbonyl (PC) were significantly increased, while a marked decrease occurred in the contents of deoxy- and ribo-nucleic acids (DNA and RNA) and glutathione (GSH) as well as activity of glutathione-S-transferase (GST). In addition, catalase (CAT) and myeloperoxidase (MPO) activities were increased. Activities of aspartate transaminase (AST), alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) were significantly increased in sera of the irradiated rats. Treatment with melatonin for 5 days after gamma-rays exposure significantly modulated the radiation-induced elevations in MDA and PC levels in the liver tissue and significantly restored hepatic GSH content, GST, CAT and MPO activities. Post-irradiation treatment with melatonin showed significant higher hepatic DNA and RNA contents than irradiated rats. The activities of AST, ALP, and GGT in serum were significantly ameliorated when melatonin was administrated after irradiation. Conclusion: Melatonin has effective

  12. Nocturnal drainage wind characteristics in two converging air sheds

    During the short experimental period in the Grants Basin of Northeastern New Mexico a survey was conducted on the complex meteorology of this area. Emphasis was placed on the nocturnal drainage flow because of the potential hazards to the populated areas of Milan and Grants from the effluents of the uranium mining and milling operation in this area. This investigation has shown that the nocturnal drainage flow patterns agree with the winds predicted on the basis of the complex terrain of the area. Because of the surface cooling at night (over 250C during summer and about 200C during winter), air from elevated surrounding areas flows to the low lying regions consequently setting up a nocturnal drainage flow. This regime exists over 60% of the time during summer months and over 65% of the time during winter months with a depth generally less than 200 m. In the San Mateo air shed the drainage flow is east northeast, and in the Ambrosia Lake air shed it is from northwest. The confluence of these two air flows contributes mainly to the drainage flow through the channel formed by La Ja Mesa and Mesa Montanosa. The analysis of data collected by the recording Flats Station confirms the prediction that although the area south of the channel region broadens considerably causing a reduction in flow speed, contributions from the southside of La Jara Mesa and Mesa Montanosa partly compensate for this reduction. The position of this recording station is 15 to 20 km from the populated towns of Milan and Grants. A drainage flow speed of approximately 2.2 m s-1 and the duration of over 11 hours as recorded by this station indicates that air from the San Mateo and Ambrosia Lake regions may be transported southwards to these population centers during a nocturnal period. In order to test this prediction, a series of multi-atmospheric tracer experiments were conducted in the Grants Basin

  13. Homeobox Genes and Melatonin Synthesis: Regulatory Roles of the Cone-Rod Homeobox Transcription Factor in the Rodent Pineal Gland

    Kristian Rohde

    2014-01-01

    Full Text Available Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processes, are also expressed in the mature rodent pineal gland. Among these, the cone-rod homeobox (CRX transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating cAMP response element-based circadian melatonin production.

  14. Some implications of melatonin use in chronopharmacology of insomnia.

    Golombek, Diego A; Pandi-Perumal, Seithikurippu R; Brown, Gregory M; Cardinali, Daniel P

    2015-09-01

    The last decade has witnessed the emergence of new chronopharmacological perspectives. In the case of sleep disorders, the accumulating evidence suggests that even a minor dysfunction in the biological clock can impact broadly upon body physiology causing increases in sleep onset latency, phase delays or advances in sleep initiation, frequent nocturnal awakenings, reduced sleep efficiency, delayed and shortened rapid eye movement sleep and increased periodic leg movements, among others. Thus, restoration of the adequate circadian pattern of proper sleep hygiene, targeted exposure to light and the use of chronobiotic drugs, such as melatonin, which affect the output phase of clock-controlled circadian rhythms, can help to recover the sleep-wake cycle. The optimization of drug effects and/or minimization of toxicity by timing medications with regard to biological rhythms is known as chronotherapeutics. While chronotherapeutical approaches have been particularly successful in the treatment of hypertension, allergies and some forms of cancer, a time-dependent pharmacological approach can be also effective when dealing with sleep disruptions like insomnia. A large proportion of patients under benzodiazepine (BZD)/Z drug treatment fail to achieve a complete and sustained recovery and are left with residual symptoms, like tolerance or dependency, that make relapse or recurrence more likely, and poorer quality of life a reality. Thus the chronic and extensive use of BZD/Z drugs has become a public health issue and has led to multiple campaigns to reduce both prescription and consumption of BZD/Z-drugs. This short review discusses available data on the efficacy of melatonin to reduce chronic BZD use in insomnia patients. PMID:26004526

  15. Melatonin implants do not alter estrogen feedback or advance puberty in gilts.

    Kennaway, D J; Hughes, P E; van Wettere, W H E J

    2015-05-01

    Puberty in pigs is often delayed during late summer and autumn, with long daylength the most likely cause. We hypothesised (1) that gilts born around the shortest day would have a later release from the negative feedback actions of estradiol than gilts born around the spring equinox and (2) melatonin treatment would result in an earlier release from estradiol negative feedback and advance the onset of puberty in gilts born around the spring equinox. We first determined the optimal number of estradiol implants required to monitor the release from estradiol negative feedback in ovariectomised gilts. Secondly we determined whether melatonin implants altered negative feedback in 4 cohorts of ovariectomised gilts born between the winter solstice and spring equinox, and in the following year whether melatonin altered the time of the first ovulation in 5 cohorts of intact gilts born between the winter solstice and spring equinox. Plasma LH and FSH increased between 126 and 210d of age (P0.05). Age at first detection of elevated plasma progesterone in untreated, intact gilts decreased across the 4 cohorts (P0.05). In conclusion, while we confirmed that estradiol sensitivity is decreased as gilts age, we failed to demonstrate any effects of season or melatonin on estradiol feedback or melatonin on puberty. PMID:25618532

  16. Effects of melatonin on lipid peroxidation and antioxidant enzymes in streptozotocin-induced diabetic rat testis

    Abdullah Armagan; Efkan Uz; H. Ramazan Yilmaz; Sedat Soyupek; Taylan Oksay; Nurten Ozcelik

    2006-01-01

    Aim: To examine the effects of melatonin treatment on lipid peroxidation (LPO) and the activities of antioxidant enzymes in the testicular tissue of streptozotocin (STZ)-induced diabetic rats. Methods: Twenty-six male rats were randomly divided into three groups as follows: group Ⅰ, control, non-diabetic rats (n = 9); group Ⅱ, STZ-induced,Following 8-week melatonin treatment, all rats were anaesthetized and then were killed to remove testes from the scrotum. Results: As compared to group Ⅰ, in rat testicular tissues of group Ⅱ, increased levels of malondialdehyde (MDA) (P < 0.01) and superoxide dismutase (SOD) (P < 0.01) as well as decreased levels of catalase (CAT) (P < 0.01)and glutathione peroxidase (GSH-Px) (P > 0.05) were found. In contrast, as compared to group Ⅱ, in rat testicular tissues of group Ⅲ, levels of MDA decreased (but this decrease was not significant, P > 0.05) and SOD (P < 0.01) as well as CAT (P < 0.05) increased. GSH-Px was not influenced by any of the treatment. Melatonin did not significantly affect the elevated glucose concentration of diabetic group. At the end of the study, there was no significant difference between the melatonin-treated group and the untreated group by means of body and testicular weight.Conclusion: Diabetes mellitus increases oxidative stress and melatonin inhibits lipid peroxidation and might regulate the activities of antioxidant enzymes of diabetic rat testes.

  17. Melatonin action in neonatal gonadotrophs

    Balík, Aleš; Kretschmannová, Karla; Mazna, Petr; Svobodová, Irena; Zemková, Hana

    2004-01-01

    Roč. 53, Suppl. 1 (2004), s. S153-S166. ISSN 0862-8408 R&D Projects: GA ČR GA309/02/1519; GA AV ČR IAA5011103; GA AV ČR IAA5011408 Institutional research plan: CEZ:AV0Z5011922 Keywords : melatonin * gonadotrophs * GnRH Subject RIV: ED - Physiology Impact factor: 1.140, year: 2004

  18. High membrane permeability for melatonin.

    Yu, Haijie; Dickson, Eamonn J; Jung, Seung-Ryoung; Koh, Duk-Su; Hille, Bertil

    2016-01-01

    The pineal gland, an endocrine organ in the brain, synthesizes and secretes the circulating night hormone melatonin throughout the night. The literature states that this hormone is secreted by simple diffusion across the pinealocyte plasma membrane, but a direct quantitative measurement of membrane permeability has not been made. Experiments were designed to compare the cell membrane permeability to three indoleamines: melatonin and its precursors N-acetylserotonin (NAS) and serotonin (5-HT). The three experimental approaches were (1) to measure the concentration of effluxing indoleamines amperometrically in the bath while cells were being dialyzed internally by a patch pipette, (2) to measure the rise of intracellular indoleamine fluorescence as the compound was perfused in the bath, and (3) to measure the rate of quenching of intracellular fura-2 dye fluorescence as indoleamines were perfused in the bath. These measures showed that permeabilities of melatonin and NAS are high (both are uncharged molecules), whereas that for 5-HT (mostly charged) is much lower. Comparisons were made with predictions of solubility-diffusion theory and compounds of known permeability, and a diffusion model was made to simulate all of the measurements. In short, extracellular melatonin equilibrates with the cytoplasm in 3.5 s, has a membrane permeability of ∼1.7 µm/s, and could not be retained in secretory vesicles. Thus, it and NAS will be "secreted" from pineal cells by membrane diffusion. Circumstances are suggested when 5-HT and possibly catecholamines may also appear in the extracellular space passively by membrane diffusion. PMID:26712850

  19. Is melatonin an adjunctive stabilizer?

    Livianos Aldana, Lorenzo; Sierra, Pilar; Arques, Sergio; García, Ana; Rojo, Luis

    2012-01-01

    MELATONIN (MLT) IS a main synchronizer of the sleep/wake cycle control. We performed a prospective naturalistic study that included 14 euthymic bipolar patients that suffered from insomnia (six type I, six type II and two schizoaffective disorder) according to DSM-IV-TR criteria.1 After giving their written consent, patients began the treatment with MLT. Evaluation tools used were: Oviedo Sleep Questionnaire (OSQ),2 Chinese Polarity Inventory (CPI),3 Numeric Evaluation Scale (NES),4 and Clini...

  20. Melatonin and cortisol profiles in late midlife and their association with age-related changes in cognition

    Waller KL

    2016-01-01

    Full Text Available Katja Linda Waller,1,2 Erik Lykke Mortensen,2,3 Kirsten Avlund,2,3,†, Merete Osler,3,4 Birgitte Fagerlund,5 Martin Lauritzen,2,6 Steen Gammeltoft,7 Poul Jennum1,2 1Danish Center for Sleep Medicine, Clinic of Clinical Neurophysiology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; 2Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; 3Department of Public Health, University of Copenhagen, Copenhagen, Denmark; 4Research Center for Prevention and Health, Rigshospitalet, Glostrup, Denmark; 5Center for Neuropsychiatric Schizophrenia Research (CNSR, Lundbeck Foundation Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS, Mental Health Center Glostrup, Glostrup, Denmark; 6Department of Clinical Neurophysiology, Rigshospitalet, Glostrup, Denmark; 7Department of Clinical Biochemistry, Rigshospitalet, Glostrup, Denmark †Kirsten Avlund passed away on June 15, 2012 Abstract: Previous studies have reported an association between circadian disturbances and age-related cognitive impairment. The aim was to study the 24-hour profiles of melatonin and cortisol in relation to cognitive function in middle-aged male subjects. Fifty healthy middle-aged males born in 1953 were recruited from a population-based cohort based on previous cognitive assessments in young adulthood and late midlife. The sample included 24 cognitively high-functioning and 26 cognitively impaired participants. Saliva samples were collected every 4 hours over a 24-hour period and analyzed for cortisol and melatonin levels by immunoassay. All participants exhibited clear circadian rhythms of salivary melatonin and cortisol. Salivary melatonin concentrations had a nocturnal peak at approximately 4 am. The median nocturnal melatonin response at 4 am was significantly lower in the cognitively impaired group than in the high-functioning group (−4.6 pg/mL, 95% CI: −7.84, −1.36, P=0.006. The 24

  1. The effects of melatonin on a molecular level

    M. Haag

    1992-07-01

    Full Text Available The indole hormone melatonin is secreted in a biphasic circadian rhythm by the pineal gland. This review presents a summary of recent results concerning — (i factors that influence melatonin synthesis; (ii the existence of melatonin receptors in brain tissue; (iii the effects of melatonin as a modulator of dopaminergic, noradrenergic, GABAergic and opioidergic neurotransmitter processes; (iv the influence of melatonin on the electric activity and metabolic rate of certain brain nuclei; and (v melatonin effects on hormone secretion in the hypothalamic-pituitary axis. A basic mechanism of melatonin action via cyclic nucleotides and thus protein phosphorylation is presented.

  2. Colour vision in diurnal and nocturnal hawkmoths.

    Kelber, Almut; Balkenius, Anna; Warrant, Eric J

    2003-08-01

    Diurnal and nocturnal hawkmoths (Sphingidae, Lepidoptera) have three spectral types of receptor sensitive to ultraviolet, blue and green light. As avid flower visitors and pollinators, they use olfactory and visual cues to find and recognise flowers. Moths of the diurnal species Macroglossum stellatarum and the nocturnal species Deilephila elpenor, Hyles lineata and Hyles gallii use and learn the colour of flowers. Nocturnal species can discriminate flowers at starlight intensities when humans and honeybees are colour-blind. M. stellatarum can use achromatic, intensity-related cues if colour cues are absent, and this is probably also true for D. elpenor. Both species can recognise colours even under a changed illumination colour. PMID:21680465

  3. [The influence of melatonin on human reproduction].

    Boczek-Leszczyk, Emilia; Juszczak, Marlena

    2007-08-01

    This paper reviews the possible participation of melatonin in the process of human reproduction. The results of several studies have shown the clear correlation between melatonin and gonadotropins and/or sexual steroids, which suggest that melatonin may be involved in the sexual maturation, ovulation or menopause. Decreased secretion of melatonin which coexists with increased fertility in the summer is specific for women living on the north hemisphere. Moreover, abnormal levels of melatonin in the blood are associated with several disorders of the hypothalamus-pituitary-gonads axis activity, i.e., precocious or delayed pubertas, hypogonadotrophic or hypergonadotrophic hypogonadism or amenorrhoea. Melatonin binding sites have been demonstrated in the central nervous system (mainly in the pars dystalis of the pituitary and hypothalamic suprachiasmatic nucleus) as well as in the reproductive organs, e.g., human granulosa cells, prostate and spermatozoa. Melatonin can, therefore, influence the gonadal function indirectly--via its effect on gonadotropin-releasing hormone and/or gonadotropins secretion. It may also act directly; several data show that melatonin can be synthesized in gonads. PMID:18044344

  4. Melatonin as an Antioxidant for Stroke Neuroprotection.

    Watson, Nate; Diamandis, Theo; Gonzales-Portillo, Chiara; Reyes, Stephanny; Borlongan, Cesar V

    2016-01-01

    Melatonin (N-acetyl-5-methoxytryptamine) is a hormone derived from the pineal gland that has a wide range of clinical applications. While melatonin was originally assessed as a hormone specializing in regulation of the normal circadian rhythm in mammals, it now has been shown to be an effective free radical scavenger and antioxidant. Current research has focused on central nervous system (CNS) disorders, stroke in particular, for potential melatonin-based therapeutics. As of now, the realm of potential therapy regimens is focused on three main treatments: exogenously delivered melatonin, pineal gland grafting, and melatonin-mediated stem cell therapy. All therapies contain both costs and benefits, and current research is still focused on finding the best treatment plan. While comprehensive research has been conducted, more research regarding the safety of such therapies is needed in order to transition into the clinical level of testing. Antioxidants such as traditional Chinese medicine, (-)-epigallocatechin-3-gallate (EGCG), and lavender oil, which have been used for thousands of years as treatment, are now gaining recognition as effective melatonin treatment alternatives. This review will further discuss relevant studies assessing melatonin-based therapeutics and provide evidence of other natural melatonin treatment alternatives for the treatment of stroke. PMID:26497887

  5. 21 CFR 522.1350 - Melatonin implant.

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Melatonin implant. 522.1350 Section 522.1350 Food... Melatonin implant. (a) Specifications. The drug is a silicone rubber elastomer implant containing 2.7...—(1) Amount. One implant per mink. (2) Indications for use. For use in healthy male and female kit...

  6. Seasonal differences in melatonin concentrations and heart rates during sleep in obese subjects in Japan

    Sato, Maki; Kanikowska, Dominika; Iwase, Satoshi; Shimizu, Yuuki; Nishimura, Naoki; Inukai, Yoko; Sato, Motohiko; Sugenoya, Junichi

    2013-09-01

    During the past several decades, obesity has been increasing globally. In Japan, obesity is defined by a BMI of 25 kg/m2 or over; 28.6 % of men and 20.6 % of women are obese. Obese people have an increased incidence of developing cardiovascular, renal, and hormonal diseases and sleep disorders. Obese people also have shortened sleep durations. We investigated seasonal differences in melatonin concentrations, heart rates, and heart rate variability during sleep in obese subjects in Japan. Five obese (BMI, 32.0 ± 4.9 kg/m2) and five non-obese (BMI, 23.2 ± 2.9 kg/m2) men participated in this study in the summer and winter. Electrocardiograms were measured continuously overnight in a climatic chamber at 26 °C with a relative humidity of 50 %. Saliva samples for melatonin were collected at 2300 hours, 0200 hours, and 0600 hours. We found that melatonin concentrations during sleep in obese subjects were significantly lower than those in non-obese subjects in the winter. Heart rate during sleep in winter was significantly higher than that in summer in both obese and non-obese subjects. Heart rate variability was not significantly different in the summer and winter in both obese and non-obese subjects. Our results show that decreased nocturnal melatonin concentrations during winter in obese men may be related to higher heart rates, and this may suggest that obese men are at an increased risk of a cardiovascular incident during sleep, especially in the winter.

  7. Effect of melatonin on endogenous circadian rhythm

    XU Feng; WANG Min; ZANG Ling-he

    2008-01-01

    Objective To further authenticate the role of melatonin on endogenous biologic clock system. Methods Pinealectomized mice were used in the experiments, a series of circadian rhythm of physiology index, such as glucocorticoid, amino acid neurotransmitter, immune function, sensitivity of algesia and body temperature were measured. Results Effects of melatonin on endogenous circadian rhythm roughly appeared four forms: 1) The model of inherent rhythm was invariant, but midvalue was removed. 2) Pacing function: pinealectomy and melatonin administration changed amplitude of the circadian vibration of aspartate, peripheral blood WBC and serum hemolysin. 3) Phase of rhythm changed, such as the effects on percentage of lymphocyte and sensitivity of algesia. 4) No effect, the circadian rhythm of body temperature belong to this form Conclusions Melatonin has effects some circadian rhythm, and it can adjust endogenous inherent rhythm and make the rhythm keep step with environmental cycle. Melatonin may be a kind of Zeitgeber, Pineal gland might being a rhythm bearing organ to some circadian rhythm.

  8. The early response of pineal N-acetyltransferase activity, melatonin and catecholamine levels in rats irradiated with gamma rays

    Male Wistar rats adapted to an artificial light-dark regimen were whole-body gamma-irradiated with a dose of 14.35 Gy. Irradiation, sham-irradiation and decapitation 30, 60 and 120 min after the exposure were performed between 2000 h and 0100 h in the darkness. The serotonin N-acetyltransferase activity (NAT), the concentration of melatonin and corticosterone were also determined. Ionizing radiation did not change the activity of NAT, the key enzyme of melatonin synthesis; however, it decreased the concentration of pineal melatonin. The concentration of pineal dopamine and norepinephrine decreased 30 and 120 min after exposure, while the concentration of epinephrine was elevated 30 min after irradiation, though later it was markedly decreased. The serum melatonin level was not changed but an increase in corticosterone level was observed. In the early period after exposure a decrease in pineal melatonin occurred, accompanied by a decrease in pineal catecholamines. On the contrary, in the phase of developed radiation injury the signs of increased melatonin synthesis were observed on days 3 and 4 after the exposure. (author) 6 figs., 25 refs

  9. Decreased melatonin levels and increased levels of advanced oxidation protein products in the seminal plasma are related to male infertility.

    Kratz, Ewa Maria; Piwowar, Agnieszka; Zeman, Michal; Stebelová, Katarína; Thalhammer, Theresia

    2016-03-01

    Melatonin, an indolamine secreted by the pineal gland, is known as a powerful free-radical scavenger and wide-spectrum antioxidant. Therefore, the aim of this study was to correlate markers of oxidative protein damage (advanced oxidation protein products, AOPPs) and the total antioxidant capacity (TAC) with melatonin levels in the seminal plasma of men with azoospermia (n=37), theratozoospermia (n=29) and fertile controls (normozoospermia, n=37). Melatonin concentration was measured by radioimmunoassay. The levels of AOPP as well as TAC efficiency (determined by the ferric reducing antioxidant power, FRAP) were estimated by spectrophotometric methods. The concentration of melatonin and AOPP significantly differed in azoospermic (P<0.0001) and theratozoospermic (P<0.0001) patients versus fertile men, and correlated negatively (r=-0.33, P=0.0016). The TAC levels were significantly higher in azoospermia than in theratozoospermia (P=0.0022) and the control group (P=0.00016). In azoospermia, the AOPP concentration was also significantly higher than that observed in theratozoospermia (P=0.00029). Decreased levels of melatonin together with elevated AOPP altered the oxidative-antioxidative balance in the ejaculate, thereby reducing fertility. Therefore, melatonin and AOPP levels may serve as additional diagnostic markers of semen quality and male reproductive potential. PMID:25218686

  10. Melatonin attenuated early brain injury induced by subarachnoid hemorrhage via regulating NLRP3 inflammasome and apoptosis signaling.

    Dong, Yushu; Fan, Chongxi; Hu, Wei; Jiang, Shuai; Ma, Zhiqiang; Yan, Xiaolong; Deng, Chao; Di, Shouyin; Xin, Zhenlong; Wu, Guiling; Yang, Yang; Reiter, Russel J; Liang, Guobiao

    2016-04-01

    Subarachnoid hemorrhage (SAH) is a devastating condition with high morbidity and mortality rates due to the lack of effective therapy. Nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation associated with the upregulation of apoptotic signaling pathway has been implicated in various inflammatory diseases including hemorrhagic insults. Melatonin is reported to possess substantial anti-inflammatory properties, which is beneficial for early brain injury (EBI) after SAH. However, the molecular mechanisms have not been clearly identified. This study was designed to investigate the protective effects of melatonin against EBI induced by SAH and to elucidate the potential mechanisms. The adult mice were subjected to SAH. Melatonin or vehicle was injected intraperitoneally 2 hr after SAH. Melatonin was neuroprotective, as shown by increased survival rate, as well as elevated neurological score, greater survival of neurons, preserved brain glutathione levels, and reduced brain edema, malondialdehyde concentrations, apoptotic ratio, and blood-brain barrier (BBB) disruption. Melatonin also attenuated the expressions of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), cleaved caspase-1, interleukin-1β (IL-1β), and interleukin-6 (IL-6); these changes were also associated with an increase in the anti-apoptotic factor (Bcl2) and reduction in the pro-apoptotic factor (Bim). In summary, our results demonstrate that melatonin treatment attenuates the EBI following SAH by inhibiting NLRP3 inflammasome-associated apoptosis. PMID:26639408

  11. Green Light for Nocturnally Migrating Birds

    Wernand, Marcel R.; Maurice A. H. Donners; Han de Vries; Ens, Bruno J.; Hanneke Poot; Joop M. Marquenie

    2008-01-01

    The nighttime sky is increasingly illuminated by artificial light sources. Although this ecological light pollution is damaging ecosystems throughout the world, the topic has received relatively little attention. Many nocturnally migrating birds die or lose a large amount of their energy reserves during migration as a result of encountering artificial light sources. This happens, for instance, in the North Sea, where large numbers of nocturnally migrating birds are attracted to the many offsh...

  12. Hypercalciuria in Children with Monosymptomatic Nocturnal Enuresis

    Mahmut Çivilibal; Ömer Sarılar; Mehmet Toptaş

    2014-01-01

    Aim: Nocturnal enuresis is a common problem in childhood. We aimed to evaluate the role of urinary calcium excretion in children with monosymptomatic nocturnal enuresis (MNE). Methods: This study included 60 children with MNE and 30 healthy controls. In addition to routine tests, urine density and urinary calcium levels were measured. Hypercalciuria was defined as the excess urinary calcium excretion ≥4mg/kg/day or urinary calcium/creatinine ratio ≥0.21. Results: Urinary calcium excreti...

  13. Nocturnal coastal fronts in the Mediterranean basin

    Mazón, Jordi

    2015-01-01

    The main goal of this thesis is to investigate the formation of nocturnal coastal fronts (hereafter CF) in the Mediterranean basin producing nocturnal offshore precipitation near the coastline. After sunset the cooled inland air moves to the coastline driven by drainage winds as a density current. When this air encounters the warm and wet sea-air a CF is formed. Therefore the warm air mass is lifted and when ascending clouds may form producing in some cases precipitation. The influence of ...

  14. Melatonin treatment during the incubation of sensitization attenuates methamphetamine-induced locomotor sensitization and MeCP2 expression.

    Wu, Jintao; Zhu, Dexiao; Zhang, Jing; Li, Guibao; Liu, Zengxun; Sun, Jinhao

    2016-02-01

    Behavior sensitization is a long-lasting enhancement of locomotor activity after exposure to psychostimulants. Incubation of sensitization is a phenomenon of remarkable augmentation of locomotor response after withdrawal and reflects certain aspects of compulsive drug craving. However, the mechanisms underlying these phenomena remain elusive. Here we pay special attention to the incubation of sensitization and suppose that the intervention of this procedure will finally decrease the expression of sensitization. Melatonin is an endogenous hormone secreted mainly by the pineal gland. It is effective in treating sleep disorder, which turns out to be one of the major withdrawal symptoms of methamphetamine (MA) addiction. Furthermore, melatonin can also protect neuronal cells against MA-induced neurotoxicity. In the present experiment, we treated mice with low dose (10mg/kg) of melatonin for 14 consecutive days during the incubation of sensitization. We found that melatonin significantly attenuated the expression of sensitization. In contrast, the vehicle treated mice showed prominent enhancement of locomotor activity after incubation. MeCP2 expression was also elevated in the vehicle treated mice and melatonin attenuated its expression. Surprisingly, correlation analysis suggested significant correlation between MeCP2 expression in the nucleus accumbens (NAc) and locomotion in both saline control and vehicle treated mice, but not in melatonin treated ones. MA also induced MeCP2 over-expression in PC12 cells. However, melatonin failed to reduce MeCP2 expression in vitro. Our results suggest that melatonin treatment during the incubation of sensitization attenuates MA-induced expression of sensitization and decreases MeCP2 expression in vivo. PMID:26416230

  15. Effect of melatonin on the severity of L-arginine-induced experimental acute pancreatitis in rats

    Annamaria Szabolcs; Zoltan Rakonczay Jr; Janos Lonovics; Tamas Takacs; Russel J Reiter; Tamas Letoha; Peter Hegyi; Gabor Papai; Ilona Varga; Katalin Jarmay; Jozsef Kaszaki; Reka Sari

    2006-01-01

    AIM: To determine the effect of melatonin pre- and post-treatment on the severity of L-arginine (L-Arg) -induced experimental pancreatitis in rats.METHODS: Male Wistar rats (25) were divided into five groups. Those in group A received two injections of 3.2 g/kg body weight L-Arg i.p. at an interval of 1 h. In group MA, the rats were treated with 50 mg/kg body weight melatonin i.p. 30 min prior to L-Arg administration. In group AM, the rats received the same dose of melatonin 1 h after L-Arg was given. In group M, a single dose of melatonin was administered as described previously. In group C the control animals received physiological saline injections i.p. All rats were exsanguinated 24 h after the second L-Arg injection.RESULTS: L-Arg administration caused severe necrotizing pancreatitis confirmed by the significant elevations in the serum amylase level, the pancreatic weight/body weight ratio (pw/bw), the pancreatic IL-6 content and the myeloperoxidase activity, relative to the control values. Elevation of the serum amylase level was significantly reduced in rats given melatonin following L-Arg compared to rats injected with L-Arg only. The activities of the pancreatic antioxidant enzymes (Cu/Zn-superoxide dismutase (Cu/Zn-SOD) and catalase (CAT)) were significantly increased 24 h after pancreatitis induction. Melatonin given in advance of L-Arg significantly reduced the pancreatic CAT activity relative to that in the rats treated with L-Arg alone. In the liver, L-Arg significantly increased the lipid peroxidation level, and the glutathione peroxidase and Cu/Zn-SOD activities, whereas the Mn-SOD activity was reduced as compared to the control rats.Melatonin pre-treatment prevented these changes.CONCLUSION: Melatonin is an antioxidant that is able to counteract some of the L-Arg-induced changes during acute pancreatitis, and may therefore be helpful in the supportive therapy of patients with acute necrotizing.pancreatitis.

  16. Effects of exposure to intermittent versus continuous red light on human circadian rhythms, melatonin suppression, and pupillary constriction.

    Ho Mien, Ivan; Chua, Eric Chern-Pin; Lau, Pauline; Tan, Luuan-Chin; Lee, Ivan Tian-Guang; Yeo, Sing-Chen; Tan, Sara Shuhui; Gooley, Joshua J

    2014-01-01

    Exposure to light is a major determinant of sleep timing and hormonal rhythms. The role of retinal cones in regulating circadian physiology remains unclear, however, as most studies have used light exposures that also activate the photopigment melanopsin. Here, we tested the hypothesis that exposure to alternating red light and darkness can enhance circadian resetting responses in humans by repeatedly activating cone photoreceptors. In a between-subjects study, healthy volunteers (n = 24, 21-28 yr) lived individually in a laboratory for 6 consecutive days. Circadian rhythms of melatonin, cortisol, body temperature, and heart rate were assessed before and after exposure to 6 h of continuous red light (631 nm, 13 log photons cm(-2) s(-1)), intermittent red light (1 min on/off), or bright white light (2,500 lux) near the onset of nocturnal melatonin secretion (n = 8 in each group). Melatonin suppression and pupillary constriction were also assessed during light exposure. We found that circadian resetting responses were similar for exposure to continuous versus intermittent red light (P = 0.69), with an average phase delay shift of almost an hour. Surprisingly, 2 subjects who were exposed to red light exhibited circadian responses similar in magnitude to those who were exposed to bright white light. Red light also elicited prolonged pupillary constriction, but did not suppress melatonin levels. These findings suggest that, for red light stimuli outside the range of sensitivity for melanopsin, cone photoreceptors can mediate circadian phase resetting of physiologic rhythms in some individuals. Our results also show that sensitivity thresholds differ across non-visual light responses, suggesting that cones may contribute differentially to circadian resetting, melatonin suppression, and the pupillary light reflex during exposure to continuous light. PMID:24797245

  17. Protein interactome mining defines melatonin MT1 receptors as integral component of presynaptic protein complexes of neurons.

    Benleulmi-Chaachoua, Abla; Chen, Lina; Sokolina, Kate; Wong, Victoria; Jurisica, Igor; Emerit, Michel Boris; Darmon, Michèle; Espin, Almudena; Stagljar, Igor; Tafelmeyer, Petra; Zamponi, Gerald W; Delagrange, Philippe; Maurice, Pascal; Jockers, Ralf

    2016-01-01

    In mammals, the hormone melatonin is mainly produced by the pineal gland with nocturnal peak levels. Its peripheral and central actions rely either on its intrinsic antioxidant properties or on binding to melatonin MT1 and MT2 receptors, belonging to the G protein-coupled receptor (GPCR) super-family. Melatonin has been reported to be involved in many functions of the central nervous system such as circadian rhythm regulation, neurotransmission, synaptic plasticity, memory, sleep, and also in Alzheimer's disease and depression. However, little is known about the subcellular localization of melatonin receptors and the molecular aspects involved in neuronal functions of melatonin. Identification of protein complexes associated with GPCRs has been shown to be a valid approach to improve our understanding of their function. By combining proteomic and genomic approaches we built an interactome of MT1 and MT2 receptors, which comprises 378 individual proteins. Among the proteins interacting with MT1 , but not with MT2 , we identified several presynaptic proteins, suggesting a potential role of MT1 in neurotransmission. Presynaptic localization of MT1 receptors in the hypothalamus, striatum, and cortex was confirmed by subcellular fractionation experiments and immunofluorescence microscopy. MT1 physically interacts with the voltage-gated calcium channel Cav 2.2 and inhibits Cav 2.2-promoted Ca(2+) entry in an agonist-independent manner. In conclusion, we show that MT1 is part of the presynaptic protein network and negatively regulates Cav 2.2 activity, providing a first hint for potential synaptic functions of MT1. PMID:26514267

  18. Melatonin in Alzheimer’s Disease

    Jian-Zhi Wang

    2013-07-01

    Full Text Available Alzheimer’s disease (AD, an age-related neurodegenerative disorder with progressive cognition deficit, is characterized by extracellular senile plaques (SP of aggregated β-amyloid (Aβ and intracellular neurofibrillary tangles, mainly containing the hyperphosphorylated microtubule-associated protein tau. Multiple factors contribute to the etiology of AD in terms of initiation and progression. Melatonin is an endogenously produced hormone in the brain and decreases during aging and in patients with AD. Data from clinical trials indicate that melatonin supplementation improves sleep, ameliorates sundowning and slows down the progression of cognitive impairment in AD patients. Melatonin efficiently protects neuronal cells from Aβ-mediated toxicity via antioxidant and anti-amyloid properties. It not only inhibits Aβ generation, but also arrests the formation of amyloid fibrils by a structure-dependent interaction with Aβ. Our studies have demonstrated that melatonin efficiently attenuates Alzheimer-like tau hyperphosphorylation. Although the exact mechanism is still not fully understood, a direct regulatory influence of melatonin on the activities of protein kinases and protein phosphatases is proposed. Additionally, melatonin also plays a role in protecting the cholinergic system and in anti-inflammation. The aim of this review is to stimulate interest in melatonin as a potentially useful agent in the prevention and treatment of AD.

  19. Melatonin level and sleep disorders in adolescents

    Andre Inigo

    2015-07-01

    Full Text Available and time of sleep. Decreased melatonin levels have been noted in people with sleep disorders. Melatonin is a neurohormone, produced mainly by the pineal gland, as well as a small part of the retina. Its function is to maintain normal circadian rhythms and it is related to sleep regulation in humans.Objective To assess for a relationship between melatonin levels and sleep disorders in adolescents.Methods We conducted a cross-sectional study on students of two secondary schools in Tuminting, Manado, North Sulawesi, from May to June 2013. Subjects were obtained by consecutive sampling for a total of 44 adolescents aged 12-15 years. Subjects filled questionnaires, underwent wrist actigraphy, and provided blood specimens for examination of melatonin levels. We used descriptive and logistic regression analyses to assess for relationships between variables.Results Thirty (68.2% subjects experienced sleep disorders. There was a significant association between decreased melatonin levels and the higher incidence of sleep disturbances (P = 0.02.Conclusion There is a correlation between melatonin levels in adolescents with sleep disorders. Decreased melatonin levels are associated with sleep disorders.

  20. Melatonin influence in ovary transplantation: systematic review.

    Shiroma, M E; Botelho, N M; Damous, L L; Baracat, E C; Soares-Jr, J M

    2016-01-01

    Melatonin is an indolamine produced by the pineal gland and it can exert a potent antioxidant effect. Its free radical scavenger properties have been used to advantage in different organ transplants in animal experiments. Several concentrations and administration pathways have been tested and melatonin has shown encouraging beneficial results in many transplants of organs such as the liver, lungs, heart, pancreas, and kidneys. The objective of the present study was to review the scientific literature regarding the use of melatonin in ovary transplantation. A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was carried out using the Cochrane and Pubmed databases and employing the terms 'melatonin' AND 'ovary' AND 'transplantation.' After analysis, 5 articles were extracted addressing melatonin use in ovary transplants and involving 503 animals. Melatonin enhanced various graft aspects like morphology, apoptosis, immunological reaction, revascularization, oxidative stress, and survival rate. Melatonin's antioxidative and antiapoptotic properties seemingly produce positive effects on ovarian graft activity. Despite the promising results, further studies in humans need to be conducted to consolidate its use, as ovary transplantation for fertility preservation is gradually being moved from the experimental stage to a clinical setting. PMID:27287621

  1. Design and rationale of a randomized controlled trial of melatonin supplementation in men and women with the metabolic syndrome

    Terry PD

    2013-03-01

    Full Text Available Paul D Terry,1 Abhinav Goyal,2,3 Lawrence S Phillips,3 Hillary M Superak,4 Michael H Kutner4 1Departments of Public Health and Surgery, University of Tennessee, Knoxville, TN, 2Department of Epidemiology, Emory Rollins School of Public Health, 3Department of Medicine, Emory School of Medicine, 4Department of Biostatistics and Bioinformatics, Emory Rollins School of Public Health, Atlanta, GA, USA Background: The metabolic syndrome is a constellation of interrelated metabolic risk factors that appear to increase the risk of atherosclerotic cardiovascular disease, type 2 diabetes mellitus, and possibly some cancers. Animal studies and observational clinical data in humans suggest that supplemental melatonin may ameliorate a number of components of the metabolic syndrome, including elevated glucose, elevated blood pressure, dyslipidemia, and obesity. The primary objective of this clinical trial was to determine the feasibility, efficacy, and safety of melatonin supplementation in men and women with the metabolic syndrome. Methods: Thirty-nine men and women of mixed race/ethnicity were enrolled into a randomized, double-blind, placebo-controlled clinical trial with two arms: placebo for 10 weeks followed by melatonin for 10 weeks, or vice versa, with an interval 6-week washout period, in a crossover trial design. Outcome measures include metabolic syndrome components (blood pressure, glucose, triglycerides, high-density lipoprotein cholesterol, waist circumference, oxidative stress, and inflammation biomarkers. These biomarkers, along with sleep duration and quality and pretreatment endogenous melatonin levels, were measured to explore possible underlying biologic mechanisms. Discussion: This trial will provide knowledge of the effects of melatonin in metabolic syndrome subjects, and lay the groundwork for future clinical trials of melatonin in metabolic syndrome subjects. Keywords: melatonin, metabolic syndrome, diabetes, blood pressure, sleep

  2. Melatonin: General Features and its Role in Psychiatric Disorders

    Murat Erdem

    2013-06-01

    Full Text Available In recent years, there is a growing interest in melatonin all over the world. The main task of protecting the body's biological clock, which set the rhythm of melatonin, involves many biological and physiological processes of the body. Cell renewal, strengthening of the immune system and body temperature regulation are other tasks of melatonin. Melatonin, with its lipophilic property, is the most powerful antioxidant as it can reach all body areas and can easily pass the blood-brain barrier. The fact that individuals with low levels of melatonin have sleep problems lead to the consideration of melatonin as a therapeutic medicine in this field. The detailed researches have shown that melatonin can improve sleep quality without changing the total duration of sleep. Nevertheless, despite high number of researches done, the functions of melatonin have not yet fully understood. Therefore, review of the available information related to melatonin will be guide for researchers in the field.

  3. Melatonin as a radioprotective agent: a review

    Melatonin (N-acetyl-5-methoxytryptamine), the chief secretory product of the pineal gland in the brain, is well known for its functional versatility. In hundreds of investigations, melatonin has been documented as a direct free radical scavenger and an indirect antioxidant, as well as an important immunomodulatory agent. The radical scavenging ability of melatonin is believed to work via electron donation to detoxify a variety of reactive oxygen and nitrogen species, including the highly toxic hydroxyl radical. It has long been recognized that the damaging effects of ionizing radiation are brought about by both direct and indirect mechanisms. The direct action produces disruption of sensitive molecules in the cells, whereas the indirect effects (∼70%) result from its interaction with water molecules, which results in the production of highly reactive free radicals such as ·OH, ·H, and eaq- and their subsequent action on subcellular structures. The hydroxyl radical scavenging ability of melatonin was used as a rationale to determine its radioprotective efficiency. Indeed, the results from many in vitro and in vivo investigations have confirmed that melatonin protects mammalian cells from the toxic effects of ionizing radiation. Furthermore, several clinical reports indicate that melatonin administration, either alone or in combination with traditional radiotherapy, results in a favorable efficacy:toxicity ratio during the treatment of human cancers. This article reviews the literature from laboratory investigations that document the ability of melatonin to scavenge a variety of free radicals (including the hydroxyl radical induced by ionizing radiation) and summarizes the evidence that should be used to design larger translational research-based clinical trials using melatonin as a radioprotector and also in cancer radiotherapy. The potential use of melatonin for protecting individuals from radiation terrorism is also considered

  4. ISOLATED REDUCED NOCTURNAL BLADDER RESERVOIR FUNCTION - A NEW TYPE OF NOCTURNAL ENURESIS

    Borg, Britt; Kamperis, Konstantinos; Rittig, Søren

    PURPOSE Bladder reservoir function in children with monosymptomatic nocturnal enuresis (MNE) is assessed by maximal voided volumes (MVV) registered on frequency-volume charts during daytime. Although a degree of association is evident, MVV does not necessarily reflect the nocturnal bladder...

  5. MT1 melatonin receptors and their role in the oncostatic action of melatonin

    Karolina Danielczyk

    2009-09-01

    Full Text Available Melatonin, the main hormone produced by the pineal gland, strongly inhibits the growth of cancer cells [i]in vitro[/i] and [i]in vivo[/i]. Some publications indicate that the addition of melatonin to culture medium slows the proliferation of some cancer cell lines. It is also suggested that melatonin used as an adjuvant benefits the effectiveness and tolerance of chemotherapy. The mechanisms of this are not fully understood, but melatonin receptors might be one of the most important elements. Two distinct types of membrane-bound melatonin receptors have been identified in humans: MT1 (Mel1a and MT2 (Mel1b receptors. These subtypes are 60�0homologous at the amino-acid level. MT1 receptors are G-protein-coupled receptors. Through the α subunit of G protein, melatonin receptors stimulate an adenylate cyclase and decrease the level of cAMP. This has a significant influence on cell proliferation and has been confirmed in many tests on different cell lines, such as S-19, B-16 murine melanoma cells, and breast cancer cells. It seems that expression of the MT1 melatonin receptors benefits the efficacy of melatonin treatment. Melatonin and its receptors may provide a promising way to establish new alternative therapeutic approaches in human cancer prevention.

  6. Alpha-2 adrenergic activity of bromocriptine and quinpirole in chicken pineal gland. Effects on melatonin synthesis and [3H]rauwolscine binding

    In the pineal gland and retina of chickens, serotonin N-acetyl-transferase (NAT) activity and melatonin content are modulated by different receptors, alpha-2 adrenergic receptors in pineal gland and D2-dopamine receptors in retina. The effect of two D2-dopamine receptor agonists, bromocriptine and quinpirole (LY 171555), on melatonin synthesis in these tissues was investigated. Systemic administrations of bromocriptine and quinpirole decreased nocturnal NAT activity and melatonin content of both pineal gland and retina. Bromocriptine was equipotent in the two tissues, whereas quinpirole was approximately 100-fold more potent in retina than in pineal gland. In pineal gland, the suppressive effects of bromocriptine and quinpirole on NAT activity were blocked by yohimbine, a selective alpha-2 adrenergic receptor antagonist, but not by spiperone, a D2-dopamine receptor antagonist. In contrast, bromocriptine- and quinpirole-induced decreases of the enzyme activity in retina were antagonized by spiperone, and not affected by yohimbine. The nocturnal increase of NAT activity of pineal glands in vitro was inhibited with an order of potency clonidine greater than bromocriptine greater than quinpirole. Additionally, bromocriptine and quinpirole displaced the specific binding of [3H]rauwolscine, an alpha-2 adrenergic receptor antagonist, to membranes from chicken pineal gland, with potencies comparable to those observed for inhibition of NAT activity in vitro. It is suggested that bromocriptine and quinpirole, in addition to their D2-dopaminergic activity, can stimulate alpha-2 adrenergic receptors in pineal gland of chicken

  7. Melatonin in perioperative medicine: Current perspective

    Souvik Maitra

    2013-01-01

    Full Text Available Melatonin, a new addition to the armamentarium of anesthesiologist, has some unique properties that are highly desirable in routine peri-operative care. Available clinical data show that preoperative melatonin is as effective as benzodiazepines in reducing preoperative anxiety with minimal action on psychomotor performance and sleep wake cycle. It may be considered as a safe and effective alternative of benzodiazepines as preoperative anxiolytic. It may have opioid sparing effect, may reduce intraocular pressure, and have role in prevention of postoperative delirium. The short-term administration of melatonin is free from significant adverse effects also.

  8. [Disruptive nocturnal behavior in elderly subjects: could it be a parasomnia?].

    Leu-Semenescu, Smaranda; Arnulf, Isabelle

    2010-06-01

    Parasomnias are sleep-related abnormal behaviors. They are frequent and overlooked causes of nocturnal disruptive behavior in the elderly, especially when patients are cognitively impaired. Confusion and violence can result in sleep disruption, injuries for the patients or their bed partners, caregivers distress, and they can be a motive for institutionalization. Parasomnias include the NonREM sleep disorders of arousal (sleepwalking, sleep terrors, confusional arousals and sleep-related eating disorder), the REM sleep behavior disorder (RBD) and more rarely the parasomnia overlap syndrome, which associates both NREM and REM parasomnias. Patients with NREM sleep parasomnias are confused, eyes open, with a glazed look during their nocturnal behaviors, and they have a post-episode amnesia. They shout and bolt from the bed (night terrors), look about in a confused manner, walk and speak (sleepwalking), and eat peculiar or inedible food (sleep-related eating disorders). These behaviors, which are frequent in young adults, may be triggered by short-half live hypnotics in elderly. During the parasomnia, the brain is partially awake (enough to perform complex motor and verbal action), and partially asleep (without conscious awareness or responsibility). RBD is characterized by a loss of the normal muscle atonia that accompanies REM sleep. Patients have excessive motor activity such as punching, kicking, or crying out in association with dream content. RBD are frequent in Parkinson's disease and dementia with Lewy bodies and may precede the cognitive or motor symptoms of these diseases by 5 to 10 years. RBD can also be promoted by antidepressants. When combined with thorough clinical interviews, the video-polysomnography is a powerful tool, especially for discriminating the parasomnia from nocturnal frontal lobe epilepsy, sleep apneas and periodic leg movements. Ensuring safety and withdrawing deleterious treatments are useful in patients with violent activities, potential

  9. Melatonin as Protection Against Radiation Injury

    Zetner, D; Andersen, L P H; Rosenberg, J

    2016-01-01

    Introduction: Radiation is widely used in the treatment of various cancers and in radiological imaging procedures. Ionizing radiation causes adverse effects, leading to decreased quality of life in patients, by releasing free radicals that cause oxidative stress and tissue damage. The sleep......-hormone melatonin is a free radical scavenger, and induces several anti-oxidative enzymes. This review investigates the scientific literature on the protective effects of melatonin against exposure to ionizing radiation, and discusses the clinical potential of melatonin as prophylactic treatment against ionizing...... radiation damage. Methods: A systematic literature search was performed and included experimental or clinical studies written in English that investigated the protective effects of melatonin against gamma or X-ray irradiation in vivo. Studies were excluded if patients were treated with chemotherapy...

  10. Melatonin Attenuates Methamphetamine-Induced Neurotoxicity.

    Wongprayoon, Pawaris; Govitrapong, Piyarat

    2016-01-01

    Methamphetamine (METH), an illegal psycho-stimulant, is widely known as a recreational drug. In addition to its addictive effect, METH induces neurotoxicity via multiple mechanisms. The major contributors to METH-induced neurotoxicity are reactive oxygen species, which lead to cell death through apoptotic pathway and disturbances in mitochondria, the generation of neuroinflammation, and autophagy. Melatonin, a neurohormone secreted by the pineal gland, is a potent antioxidant compound that plays a beneficial role by protecting against the oxidative stress caused by METH. Melatonin also plays a role in maintaining mitochondrial homeostasis. Nanomolar concentrations of melatonin have been shown to protect against the inflammation caused by METH and to prevent the decrease in neurogenesis caused by METH in progenitor cells obtained from adult rat hippocampal tissue. The intent of this review is to describe the underlying mechanisms involving melatonin that protect against the neurodegeneration caused by METH. PMID:25248807

  11. A Review of Melatonin, Its Receptors and Drugs

    Emet, Mucahit; Ozcan, Halil; Ozel, Lutfu; Yayla, Muhammed; Halici, Zekai; Hacimuftuoglu, Ahmet

    2016-01-01

    After a Turkish scientist took Nobel Prize due to his contributions to understand clock genes, melatonin, closely related to these genes, may begin to shine. Melatonin, a hormone secreted from the pineal gland at night, plays roles in regulating sleep-wake cycle, pubertal development and seasonal adaptation. Melatonin has antinociceptive, antidepressant, anxiolytic, antineophobic, locomotor activity-regulating, neuroprotective, anti-inflammatory, pain-modulating, blood pressure-reducing, retinal, vascular, anti-tumor and antioxidant effects. It is related with memory, ovarian physiology, and osteoblast differentiation. Pathologies associated with an increase or decrease in melatonin levels are summarized in the review. Melatonin affects by four mechanisms: 1) Binding to melatonin receptors in plasma membrane, 2) Binding to intracellular proteins such as calmoduline, 3) Binding to Orphan nuclear receptors, and 4) Antioxidant effect. Receptors associated with melatonin are as follows: 1) Melatonin receptor type 1a: MT1 (on cell membrane), 2) Melatonin receptor type 1b: MT2 (on cell membrane), 3) Melatonin receptor type 1c (found in fish, amphibians and birds), 4) Quinone reductase 2 enzyme (MT3 receptor, a detoxification enzyme), 5) RZR/RORα: Retinoid-related Orphan nuclear hormone receptor (with this receptor, melatonin binds to the transcription factors in nucleus), and 6) GPR50: X-linked Melatonin-related Orphan receptor (it is effective in binding of melatonin to MT1). Melatonin agonists such as ramelteon, agomelatine, circadin, TIK-301 and tasimelteon are introduced and side effects will be discussed. In conclusion, melatonin and related drugs is a new and promising era for medicine. Melatonin receptors and melatonin drugs will take attention with greater interest day by day in the future. PMID:27551178

  12. Melatonin in perioperative medicine: Current perspective

    Souvik Maitra; Dalim Kumar Baidya; Puneet Khanna

    2013-01-01

    Melatonin, a new addition to the armamentarium of anesthesiologist, has some unique properties that are highly desirable in routine peri-operative care. Available clinical data show that preoperative melatonin is as effective as benzodiazepines in reducing preoperative anxiety with minimal action on psychomotor performance and sleep wake cycle. It may be considered as a safe and effective alternative of benzodiazepines as preoperative anxiolytic. It may have opioid sparing effect, may reduce ...

  13. Color indirect effects on melatonin regulation

    Mian, Tian; Liu, Timon C.; Li, Yan

    2002-04-01

    Color indirect effect (CIE) is referred to as the physiological and psychological effects of color resulting from color vision. In previous papers, we have studied CIE from the viewpoints of the integrated western and Chinese traditional medicine, put forward the color-autonomic- nervous-subsystem model (CAM), and provided its time-theory foundation. In this paper, we applied it to study light effects on melatonin regulation in humans, and suggested that it is CIE that mediates light effects on melatonin suppression.

  14. Clinical Uses of Melatonin in Pediatrics

    Emilio J. Sánchez-Barceló; Mediavilla, Maria D; Russel J. Reiter

    2011-01-01

    This study analyzes the results of clinical trials of treatments with melatonin conducted in children, mostly focused on sleep disorders of different origin. Melatonin is beneficial not only in the treatment of dyssomnias, especially delayed sleep phase syndrome, but also on sleep disorders present in children with attention-deficit hyperactivity, autism spectrum disorders, and, in general, in all sleep disturbances associated with mental, neurologic, or other medical disorders. Sedative prop...

  15. Melatonin alleviates hyperthyroidism induced oxidative stress and neuronal cell death in hippocampus of aged female golden hamster, Mesocricetus auratus.

    Rao, Geeta; Verma, Rakesh; Mukherjee, Arun; Haldar, Chandana; Agrawal, Neeraj Kumar

    2016-09-01

    Oxidative stress is a well known phenomenon under hyperthyroid condition that induces various physiological and neural problems with a higher prevalence in females. We, therefore investigated the antioxidant potential of melatonin (Mel) on hyperthyroidism-induced oxidative stress and neuronal cell death in the hippocampus region of brain (cognition and memory centre) of aged female golden hamster, Mesocricetus auratus. Aged female hamsters were randomly divided into four experimental groups (n=7); group-I: control, group-II: Melatonin (5mgkg(-1)day(-1), i.p., for one week), group-III: Hyperthyroid (100μg kg(-1)day(-1), i.p., for two weeks) and group-IV- Hyper+Mel. Hormonal profiles (thyroid and melatonin), activity of antioxidant enzymes (SOD, CAT and GPX), lipid peroxidation level (TBARS) and the specific apoptotic markers (Bax/Bcl-2 ratio and Caspase-3) expression were evaluated. A significant increase in the profile of total thyroid hormone (tT3 and tT4) in hyperthyroidic group as compared to control while tT3 significantly decreased in melatonin treated hyperthyroidic group. However, Mel level significantly decreased in hyperthyroidic group but increased in melatonin treated hyperthyroidic group. Further, the number of immune-positive cells for thyroid hormone receptor-alpha (TR-α) decreased in the hippocampus of hyperthyroidic group and increased in melatonin treated hyperthyroidic group. Profiles of antioxidant enzymes showed a significant decrease in hyperthyroidic group with a simultaneous increase in lipid peroxidation (TBARS). Melatonin treatment to hyperthyroidic group lead to decreased TBARS level with a concomitant increase in antioxidant enzyme activity. Moreover, increased expression of Bax/Bcl-2 ratio and Caspase-3, in hyperthyroidic group had elevated neuronal cell death in hippocampal area and melatonin treatment reduced its expression in hyperthyroidic group. Our findings thus indicate that melatonin reduced the hyperthyroidism

  16. Identification of melatonin in Trichoderma spp. and detection of melatonin content under controlled-stress growth conditions from T. asperellum.

    Liu, Tong; Zhao, Fengzhou; Liu, Zhen; Zuo, Yuhu; Hou, Jumei; Wang, Yanjie

    2016-07-01

    T. koningii, T. harzianum, T. asperellum, T. longibrachiatum, and T. viride were analyzed using liquid chromatography-tandem mass spectrometry to determine whether melatonin is present. Results showed that there were abundant amounts of endogenous melatonin in five Trichoderma species, but no melatonin was found in any of the culture filtrates. T. asperellum had the highest amount of melatonin (27.588 ± 0.326 μg g(-1) dry mass), followed by T. koningii, T. harzianum, T. longibrachiatum, and T. viride. The endogenous melatonin content of T. asperellum in controlled-stress growth conditions was also detected. The data showed that chemical stressors (CdCl2 , CuSO4 , and H2 O2 ) provoked an increase in endogenous melatonin levels. CdCl2 had the highest stimulatory effect on melatonin production, as the product reached reaching up to three times the melatonin content of the control. NaCl stimulated a decrease of melatonin. Acidic conditions (pH 3 and pH 5) as well as slightly alkaline conditions (pH 9) resulted in an increase in the melatonin content, whereas pH11 resulted in a significant decrease in the melatonin content, only 12.276 ± 0.205 μg g(-1) dry mass. The current study is first to report melatonin content and the change of melatonin content under different stress situations in Trichoderma spp. PMID:26367376

  17. Iatrogenic nocturnal eneuresis- an overlooked side effect of anti histamines?

    D Italiano

    2015-01-01

    Full Text Available Nocturnal enuresis is a common disorder in childhood, but its pathophysiological mechanisms have not been fully elucidated. Iatrogenic nocturnal enuresis has been described following treatment with several psychotropic medications. Herein, we describe a 6-year-old child who experienced nocturnal enuresis during treatment with the antihistamine cetirizine. Drug rechallenge was positive. Several neurotransmitters are implicated in the pathogenesis of nocturnal enuresis, including noradrenaline, serotonin and dopamine. Antihistamine treatment may provoke functional imbalance of these pathways resulting in incontinence.

  18. Melatonin in sleepless children : everything has a rhythm?

    van Geijlswijk, I.M.

    2011-01-01

    Every living organism has an biological clock regulating endogenous melatonin production, synchronized by exogenous impulses like daylight, temperature and feeding. Inappropriately applied bright light disturbs this melatonin rhythm. Some large swine producers apply artificial light three times a da

  19. Melatonin ameliorates metabolic risk factors, modulates apoptotic proteins, and protects the rat heart against diabetes-induced apoptosis.

    Amin, Ali H; El-Missiry, Mohamed A; Othman, Azza I

    2015-01-15

    The present study investigated the ability of melatonin in reducing metabolic risk factors and cardiac apoptosis induced by diabetes. Streptozotocin (60 mg/kg, i.p.) was injected into male rats, and after diabetic induction melatonin (10mg/kg i.g.) was administered orally for 21 days. Diabetic hearts showed increased number of apoptotic cells with downregulation of Bcl-2 and activation of p53 and CD95 as well as the caspases 9, 8 and 3. In addition, there was a significant decrease in insulin level, hyperglycemia, elevated HOMA-IR, glycosylated hemoglobin (HbA1c), total lipids, triglycerides, total cholesterol, low and very low-density lipoprotein and decreased high-density lipoprotein. These changes were coupled with a significant increase in the activities of creatin kinase-MB (CK-MB) and lactate dehydrogenase (LDH) in the serum of the diabetic rats indicating myocardium injury. Oral administration of melatonin for 3 weeks after diabetes induction ameliorated the levels of hyperglycemia, insulin, HbA1c, lipids profile and HOMA-IR. The oral melatonin treatment of diabetic rats significantly decreased the number of apoptotic cells in the heart compared to diabetic rats. It enhanced Bcl-2 expression and blocked the activation of CD95 as well as caspases 9, 8 and 3. These changes were accompanied with significant improvement of CK-MB and LDH in the serum indicating the ameliorative effect of melatonin on myocardium injury. Melatonin effectively ameliorated diabetic myocardium injury, apoptosis, reduced the metabolic risk factors and modulated important steps in both extrinsic and intrinsic pathways of apoptosis. Thus, melatonin may be a promising pharmacological agent for ameliorating potential cardiomyopathy associated with diabetes. PMID:25510232

  20. Melatonin differentially affects vascular blood flow in humans

    Cook, Jonathan S.; Sauder, Charity L.; Ray, Chester A.

    2010-01-01

    Melatonin is synthesized and released into the circulation by the pineal gland in a circadian rhythm. Melatonin has been demonstrated to differentially alter blood flow to assorted vascular beds by the activation of different melatonin receptors in animal models. The purpose of the present study was to determine the effect of melatonin on blood flow to various vascular beds in humans. Renal (Doppler ultrasound), forearm (venous occlusion plethysmography), and cerebral blood flow (transcranial...

  1. Folic acid and melatonin ameliorate carbon tetrachloride-induced hepatic injury, oxidative stress and inflammation in rats

    Ebaid Hossam

    2013-02-01

    Full Text Available Abstract This study investigated the protective effects of melatonin and folic acid against carbon tetrachloride (CCl4-induced hepatic injury in rats. Oxidative stress, liver function, liver histopathology and serum lipid levels were evaluated. The levels of protein kinase B (Akt1, interferon gamma (IFN-γ, programmed cell death-receptor (Fas and Tumor necrosis factor-alpha (TNF-α mRNA expression were analyzed. CCl4 significantly elevated the levels of lipid peroxidation (MDA, cholesterol, LDL, triglycerides, bilirubin and urea. In addition, CCl4 was found to significantly suppress the activity of both catalase and glutathione (GSH and decrease the levels of serum total protein and HDL-cholesterol. All of these parameters were restored to their normal levels by treatment with melatonin, folic acid or their combination. An improvement of the general hepatic architecture was observed in rats that were treated with the combination of melatonin and folic acid along with CCl4. Furthermore, the CCl4-induced upregulation of TNF-α and Fas mRNA expression was significantly restored by the three treatments. Melatonin, folic acid or their combination also restored the baseline levels of IFN-γ and Akt1 mRNA expression. The combination of melatonin and folic acid exhibited ability to reduce the markers of liver injury induced by CCl4 and restore the oxidative stability, the level of inflammatory cytokines, the lipid profile and the cell survival Akt1 signals.

  2. Protective Effect of Melatonin on Acute Pancreatitis

    Jolanta Jaworek

    2012-01-01

    Full Text Available Melatonin, a product of the pineal gland, is released from the gut mucosa in response to food ingestion. Specific receptors for melatonin have been detected in many gastrointestinal tissues including the pancreas. Melatonin as well as its precursor, L-tryptophan, attenuates the severity of acute pancreatitis and protects the pancreatic tissue from the damage caused by acute inflammation. The beneficial effect of melatonin on acute pancreatitis, which has been reported in many experimental studies and supported by clinical observations, is related to: (1 enhancement of antioxidant defense of the pancreatic tissue, through direct scavenging of toxic radical oxygen (ROS and nitrogen (RNS species, (2 preservation of the activity of antioxidant enzymes; such as superoxide dismutase (SOD, catalase (CAT, or glutathione peroxidase (GPx, (3 the decline of pro-inflammatory cytokine tumor necrosis α (TNFα production, accompanied by stimulation of an anti-inflammatory IL-10, (4 improvement of pancreatic blood flow and decrease of neutrophil infiltration, (5 reduction of apoptosis and necrosis in the inflamed pancreatic tissue, (6 increased production of chaperon protein (HSP60, and (7 promotion of regenerative process in the pancreas. Conclusion. Endogenous melatonin produced from L-tryptophan could be one of the native mechanisms protecting the pancreas from acute damage and accelerating regeneration of this gland. The beneficial effects of melatonin shown in experimental studies suggest that melatonin ought to be employed in the clinical trials as a supportive therapy in acute pancreatitis and could be used in people at high risk for acute pancreatitis to prevent the development of pancreatic inflammation.

  3. The Behavioral Treatment of Childhood Nocturnal Enuresis.

    Wagner, William G.

    1987-01-01

    Notes that of the treatments attempted for nocturnal enuresis, pharmacotherapy, individual psychotherapy, and behavioral conditioning, the most effective is behavioral conditioning with a urine alarm. Reviews the enuresis literature and provides recommendations for use of the urine alarm approach. (Author/ABB)

  4. Nocturnal faecal soiling and anal masturbation.

    A. F. Clark; Tayler, P J; Bhate, S R

    1990-01-01

    Two cases of late onset faecal soiling as a result of anal masturbation in children who were neither mentally handicapped nor psychotic were studied. The role of soiling in aiding the young person and his family to avoid separating and maturing is highlighted. We suggest that the association of anal masturbation and resistant nocturnal soiling may be unrecognised.

  5. Efficacy and safety of prolonged-release melatonin for insomnia in middle-aged and elderly patients with hypertension: a combined analysis of controlled clinical trials

    Lemoine P; Wade AG; Katz A; Nir T; Zisapel N

    2012-01-01

    Patrick Lemoine1, Alan G Wade2, Amnon Katz3, Tali Nir3, Nava Zisapel3,41The Clinique Lyon-Lumière, Meyzieu, France; 2CPS Research, 3 Todd Campus, Glasgow, UK; 3Neurim Pharmaceuticals Ltd, Tel-Aviv, Israel; 4Department of Neurobiology Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, IsraelBackground: Add-on prolonged-release melatonin (PRM) in antihypertensive therapy has been shown to ameliorate nocturnal hypertension. Hypertension is a major comorbidity among insomnia pati...

  6. The in vitro and in ovo effects of environmental illumination and temperature on the melatonin secretion from the embryonic chicken pineal gland.

    Faluhelyi, Nándor; Matkovits, Attila; Párniczky, Andrea; Csernus, Valér

    2009-04-01

    Pineal glands of chicken embryos were placed into a perifusion system for 4 days. The pineal glands were illuminated or exposed to elevated temperature for 8 or 12 h during the in vitro experiment and/or in ovo. Both daily illumination and repeated elevations of environmental temperature transitionally inhibited melatonin release before, and controlled the phase of melatonin rhythm after, the 17th day of embryonic life (E17). In addition, the in ovo rhythmic illumination applied before E13 advances the development of the circadian hormone synthesis. PMID:19456366

  7. Antidepressant- and anxiolytic effects of the novel melatonin agonist Neu-P11 in rodent models

    Tian, Shao-wen; Laudon, Moshe; Han, Li; Gao, Jun; Huang, Fu-lian; Yang, Yu-feng; Deng, Hai-feng

    2010-01-01

    Aim: To investigate the potential antidepressant and anxiolytic effects of Neu-P11, a novel melatonin agonist, in two models of depression in rats and a model of anxiety in mice. Methods: In the learned helplessness test (LH), Neu-P11 or melatonin (25–100 mg/kg, ip) was administered to rats 2 h before the beginning of the dark phase once a day for 5 days and the number of escape failures and intertrial crossings during the test phase were recorded. In the forced swimming test (FST), rats received a single or repeated administration of Neu-P11 (25–100 mg/kg, ip). The total period of immobility during the test phase was assessed. In the elevated plus-maze test (EPM), mice were treated with Neu-P11 (25–100 mg/kg, ip) or melatonin in the morning or in the evening and tested 2 h later. The percentage of time spent in the open arms and the open arms entries were assessed. Results: In the LH test, Neu-P11 but not melatonin significantly decreased the escape deficit and had no effect on the intertrial crossings. In the FST, a single or repeated administration of Neu-P11, either in the morning or in the evening, significantly decreased the duration of immobility. In the EPM test, Neu-P11 significantly increased the percentage of time spent in the open arms and the open arms entries irrespective to the time of administration. Melatonin was effective only when administered in the afternoon. Conclusion: The results demonstrate that Neu-P11 exerts antidepressant and anxiolytic activities in rodent models. PMID:20581849

  8. Elevating your elevator talk

    An important and often overlooked item that every early career researcher needs to do is compose an elevator talk. The elevator talk, named because the talk should not last longer than an average elevator ride (30 to 60 seconds), is an effective method to present your research and yourself in a clea...

  9. Melatonin in Mitochondrial Dysfunction and Related Disorders

    Venkatramanujam Srinivasan

    2011-01-01

    Full Text Available Mitochondrial dysfunction is considered one of the major causative factors in the aging process, ischemia/reperfusion (I/R, septic shock, and neurodegenerative disorders like Parkinson's disease (PD, Alzheimer's disease (AD, and Huntington's disease (HD. Increased free radical generation, enhanced mitochondrial inducible nitric oxide (NO synthase activity, enhanced NO production, decreased respiratory complex activity, impaired electron transport system, and opening of mitochondrial permeability transition pore all have been suggested as factors responsible for impaired mitochondrial function. Melatonin, the major hormone of the pineal gland, also acts as an antioxidant and as a regulator of mitochondrial bioenergetic function. Both in vitro and in vivo, melatonin was effective for preventing oxidative stress/nitrosative stress-induced mitochondrial dysfunction seen in experimental models of PD, AD, and HD. In addition, melatonin is known to retard aging and to inhibit the lethal effects of septic shock or I/R lesions by maintaining respiratory complex activities, electron transport chain, and ATP production in mitochondria. Melatonin is selectively taken up by mitochondrial membranes, a function not shared by other antioxidants. Melatonin has thus emerged as a major potential therapeutic tool for treating neurodegenerative disorders such as PD or AD, and for preventing the lethal effects of septic shock or I/R.

  10. Melatonin rhythms in Pony mares and foals.

    Kilmer, D M; Sharp, D C; Berglund, L A; Grubaugh, W; McDowell, K J; Peck, L S

    1982-01-01

    Melatonin concentrations in intact (N = 3) and sham-operated (N = 3) mares during March were greater (P less than 0 . 05) during the night than during the day, but this pattern was not seen in 3 mares from which the superior cervical ganglia had been removed bilaterally. When 4 Pony mares were exposed to a photoperiod of 10L:14D for 3 weeks and then to continuous darkness (0L:24D) for another 3 weeks, melatonin levels were greater (P less than 0 . 05) at the end of the 0L:24D period than during the earlier period and still displayed rhythmic fluctuations but were no longer co-ordinated with equivalent day/night rhythms or among mares. When melatonin rhythms were monitored in 3 mares and their foals housed in open pens exposed to natural lighting, significant time trends in melatonin concentrations were observed in mares when the foals were aged 1-3, 4-6 and 7-11 weeks, but foals did not display significant times trends in melatonin until they were 7-11 weeks old. PMID:6962864

  11. Distribution of melatonin receptor in human fetal brain

    WANG Guo-quan; SHAO Fu-yuan; ZHAO Ying; LIU Zhi-min

    2001-01-01

    Objective: To study the distribution of 2 kinds of melatonin receptor subtypes (mtl and MT2) in human fetal brain. Methods: The fetal brain tissues were sliced and the distribution ofmelatonin receptors in human fetal brain were detected using immunohistochemistry and in situ hybridization. Results: Melatonin receptor mtl existed in the cerebellun and hypothalamus, melatonin receptor MT2 exists in hypothalamus, occipital and medulla. Conclusion: Two kinds of melatonin receptors, mtl and MT2 exist in the membrane and cytosol of brain cells, indicating that human fetal brain is a target organ of melatonin.

  12. Aging and oxygen toxicity: Relation to changes in melatonin

    Russel J. Reiter

    1997-01-01

    Melatonin (N-acetyl-5-methoxytryptamine) is a chemical mediator produced in the pineal gland and other sites in the body. The melatonin found in the blood is derived almost exclusively from the pineal gland. Since the pineal synthesizes melatonin primarily at night, blood levels of the indole are also higher at night (5–15 fold) than during the day. Some individuals on a nightly basis produce twice as much melatonin as others of the same age. Throughout life, the melatonin rhythm gradually wa...

  13. Melatonin lowers edema after spinal cord injur y

    Cheng Li; Xiao Chen; Suchi Qiao; Xinwei Liu; Chang Liu; Degang Zhu; Jiacan Su; Zhiwei Wang

    2014-01-01

    Melatonin has been shown to diminish edema in rats. Melatonin can be used to treat spinal cord injury. This study presumed that melatonin could relieve spinal cord edema and examined how it might act. Our experiments found that melatonin (100 mg/kg, i.p.) could reduce the water content of the spinal cord, and suppress the expression of aquaporin-4 and glial ifbrillary acidic protein after spinal cord injury. This suggests that the mechanism by which melatonin alleviates the damage to the spinal cord by edema might be related to the expression of aquaporin-4 and glial ifbrillary acidic protein.

  14. Melatonin Preserves Blood-Brain Barrier Integrity and Permeability via Matrix Metalloproteinase-9 Inhibition

    Alluri, Himakarnika; Wilson, Rickesha L.; Anasooya Shaji, Chinchusha; Wiggins-Dohlvik, Katie; Patel, Savan; Liu, Yang; Peng, Xu; Beeram, Madhava R.; Davis, Matthew L.; Huang, Jason H.; Tharakan, Binu

    2016-01-01

    Microvascular hyperpermeability that occurs at the level of the blood-brain barrier (BBB) often leads to vasogenic brain edema and elevated intracranial pressure following traumatic brain injury (TBI). At a cellular level, tight junction proteins (TJPs) between neighboring endothelial cells maintain the integrity of the BBB via TJ associated proteins particularly, zonula occludens-1 (ZO-1) that binds to the transmembrane TJPs and actin cytoskeleton intracellularly. The pro-inflammatory cytokine, interleukin-1β (IL-1β) as well as the proteolytic enzymes, matrix metalloproteinase-9 (MMP-9) are key mediators of trauma-associated brain edema. Recent studies indicate that melatonin a pineal hormone directly binds to MMP-9 and also might act as its endogenous inhibitor. We hypothesized that melatonin treatment will provide protection against TBI-induced BBB hyperpermeability via MMP-9 inhibition. Rat brain microvascular endothelial cells grown as monolayers were used as an in vitro model of the BBB and a mouse model of TBI using a controlled cortical impactor was used for all in vivo studies. IL-1β (10 ng/mL; 2 hours)-induced endothelial monolayer hyperpermeability was significantly attenuated by melatonin (10 μg/mL; 1 hour), GM6001 (broad spectrum MMP inhibitor; 10 μM; 1 hour), MMP-9 inhibitor-1 (MMP-9 specific inhibitor; 5 nM; 1 hour) or MMP-9 siRNA transfection (48 hours) in vitro. Melatonin and MMP-9 inhibitor-1 pretreatment attenuated IL-1β-induced MMP-9 activity, loss of ZO-1 junctional integrity and f-actin stress fiber formation. IL-1β treatment neither affected ZO-1 protein or mRNA expression or cell viability. Acute melatonin treatment attenuated BBB hyperpermeability in a mouse controlled cortical impact model of TBI in vivo. In conclusion, one of the protective effects of melatonin against BBB hyperpermeability occurs due to enhanced BBB integrity via MMP-9 inhibition. In addition, acute melatonin treatment provides protection against BBB

  15. Intracoronary and systemic melatonin to patients with acute myocardial infarction

    Halladin, Natalie L; Busch, Sarah Ekeløf; Jensen, Svend Eggert;

    2014-01-01

    INTRODUCTION: Ischaemia-reperfusion injury following acute myocardial infarctions (AMI) is an unavoidable consequence of the primary percutaneous coronary intervention (pPCI) procedure. A pivotal mechanism in ischaemia-reperfusion injury is the production of reactive oxygen species following...... following pPCI in patients with AMI. MATERIAL AND METHODS: The IMPACT trial is a multicentre, randomised, double-blinded, placebo-controlled study. We wish to include 2 × 20 patients with ST-elevation myocardial infarctions undergoing pPCI within six hours from symptom onset. The primary end-point is the...... Myocardial Salvage Index assessed by cardiovascular magnetic resonance imaging on day 4 (± 1) after pPCI. The secondary end-points are high-sensitivity troponin, creatinekinase myocardial band and clinical events. CONCLUSION: The aim of the IMPACT trial is to evaluate the effect of melatonin on reperfusion...

  16. The role of melatonin as an antioxidant in the follicle

    Tamura Hiroshi

    2012-01-01

    Full Text Available Abstract Melatonin (N-acetyl-5-methoxytryptamine is secreted during the dark hours at night by pineal gland, and it regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. It has been believed that melatonin regulates ovarian function by the regulation of gonadotropin release in the hypothalamus-pituitary gland axis via its specific receptors. In addition to the receptor mediated action, the discovery of melatonin as a direct free radical scavenger has greatly broadened the understanding of melatonin's mechanisms which benefit reproductive physiology. Higher concentrations of melatonin have been found in human preovulatory follicular fluid compared to serum, and there is growing evidence of the direct effects of melatonin on ovarian function especially oocyte maturation and embryo development. Many scientists have focused on the direct role of melatonin on oocyte maturation and embryo development as an anti-oxidant to reduce oxidative stress induced by reactive oxygen species, which are produced during ovulation process. The beneficial effects of melatonin administration on oocyte maturation and embryo development have been confirmed by in vitro and in vivo experiments in animals. This review also discusses the first application of melatonin to the clinical treatment of infertile women and confirms that melatonin administration reduces intrafollicular oxidative damage and increase fertilization rates. This review summarizes our recent works and new findings related to the reported beneficial effects of melatonin on reproductive physiology in its role as a reducer of oxidative stress, especially on oocyte maturation and embryo development.

  17. Unlike the synchronous Plasmodium falciparum and P. chabaudi infection, the P. berghei and P. yoelii asynchronous infections are not affected by melatonin

    Piero Bagnaresi

    2009-04-01

    Full Text Available Piero Bagnaresi1, Eduardo Alves1, Henrique Borges da Silva1, Sabrina Epiphanio2, Maria M Mota2, Célia RS Garcia11Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil; 2Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, PortugalAbstract: We have previously reported that Plasmodium chabaudi and P. falciparum sense the hormone melatonin and this could be responsible for the synchrony of malaria infection. In P. chabaudi and P. falciparum, melatonin induces calcium release from internal stores, and this response is abolished by U73122, a phospholipase C inhibitor, and luzindole, a melatoninreceptor competitive antagonist. Here we show that, in vitro, melatonin is not able to modulate cell cycle, nor to elicit an elevation in intracellular calcium concentration of the intraerythrocytic forms of P. berghei or P. yoelii, two rodent parasites that show an asynchrononous development in vivo. Interestingly, melatonin and its receptor do not seem to play a role during hepatic infection by P. berghei sporozoites either. These data strengthen the hypothesis that hostderived melatonin does not synchronize malaria infection caused by P. berghei and P. yoelii. Moreover, these data explain why infections by these parasites are asynchronous, contrary to what is observed in P. falciparum and P. chabaudi infections.Keywords: malaria, calcium, melatonin, cell cycle, rhythm, sporozoite

  18. Alanine aminotransferase is associated with an adverse nocturnal blood glucose profile in individuals with normal glucose regulation.

    Jian Zhou

    Full Text Available OBJECTIVE: Although the association between alanine aminotransferase (ALT levels and risk of type 2 diabetes is well-studied, the effects of slightly increased ALT levels within the normal range on the temporal normal glucose profile remains poorly understood. METHODS: A total of 322 Chinese subjects without impaired glucose tolerance or previous diagnoses of diabetes were recruited for study from 10 hospitals in urban areas across China. All subjects wore a continuous glucose monitoring (CGM system for three consecutive days. The diurnal (06∶00-20∶00 and nocturnal (20∶00-06∶00 mean blood glucose (MBG levels were calculated. Subjects were stratified by ALT quartile level and correlation analyses were performed. RESULTS: The median ALT level was 17 IU/L, and subjects with ALT ≥17 IU/L had higher nocturnal MBG level than those with ALT 0.05. Multivariate stepwise regression analysis of elevated nocturnal MBG identified increased HOMA-IR, elevated ALT levels, and decreased homeostatic model assessment of ß-cell function as independent factors (all, P<0.05. CONCLUSIONS: Mildly elevated ALT levels, within the normal range, are associated with unfavorable nocturnal glucose profiles in Chinese subjects with normal glucose regulation.

  19. Alanine Aminotransferase Is Associated with an Adverse Nocturnal Blood Glucose Profile in Individuals with Normal Glucose Regulation

    Li, Hong; Ran, Xingwu; Yang, Wenying; Li, Qiang; Peng, Yongde; Li, Yanbing; Gao, Xin; Luan, Xiaojun; Wang, Weiqing; Jia, Weiping

    2013-01-01

    Objective Although the association between alanine aminotransferase (ALT) levels and risk of type 2 diabetes is well-studied, the effects of slightly increased ALT levels within the normal range on the temporal normal glucose profile remains poorly understood. Methods A total of 322 Chinese subjects without impaired glucose tolerance or previous diagnoses of diabetes were recruited for study from 10 hospitals in urban areas across China. All subjects wore a continuous glucose monitoring (CGM) system for three consecutive days. The diurnal (06∶00–20∶00) and nocturnal (20∶00–06∶00) mean blood glucose (MBG) levels were calculated. Subjects were stratified by ALT quartile level and correlation analyses were performed. Results The median ALT level was 17 IU/L, and subjects with ALT ≥17 IU/L had higher nocturnal MBG level than those with ALT 0.05). Multivariate stepwise regression analysis of elevated nocturnal MBG identified increased HOMA-IR, elevated ALT levels, and decreased homeostatic model assessment of ß-cell function as independent factors (all, P<0.05). Conclusions Mildly elevated ALT levels, within the normal range, are associated with unfavorable nocturnal glucose profiles in Chinese subjects with normal glucose regulation. PMID:23424646

  20. Enhancement of melatonin photostability by encapsulation in lipospheres.

    Tursilli, Rosanna; Casolari, Alberto; Iannuccelli, Valentina; Scalia, Santo

    2006-03-01

    The effect of lipid microparticle carrier systems on the light-induced degradation of melatonin was investigated. Microspheres loaded with melatonin were prepared using tristearin or tripalmitin as the lipid material and hydrogenated phosphatidylcholine or polysorbate 60 as the emulsifier. The obtained lipid microspheres were characterized by scanning-electron microscopy and differential scanning calorimetry. Free or microencapsulated melatonin was incorporated in a model cream formulation (oil-in-water emulsion) and irradiated with a solar simulator. The extent of photodegradation was measured by high-performance liquid chromatography. The photolysis experiments demonstrated that the light-induced decomposition of melatonin was markedly decreased by encapsulation into lipid microspheres based on tristearin and phosphatidylcholine (the extent of degradation was 19.6% for unencapsulated melatonin compared to 5.6% for the melatonin-loaded microparticles). Therefore, incorporation in lipid microparticles can be considered an effective system to enhance the photostability of melatonin. PMID:16242283

  1. Pharmacokinetics of oral and intravenous melatonin in healthy volunteers

    Andersen, Lars P H; Werner, Mads U; Rosenkilde, Mette M;

    2016-01-01

    BACKGROUND: The aim was to investigate the pharmacokinetics of oral and iv melatonin in healthy volunteers. METHODS: The study was performed as a cohort crossover study. The volunteers received either 10 mg oral melatonin or 10 mg intravenous melatonin on two separate study days. Blood samples were...... collected at different time points following oral administration and short iv infusion, respectively. Plasma melatonin concentrations were determined by RIA technique. Pharmacokinetic analyses were performed by "the method of residuals" and compartmental analysis. The pharmacokinetic variables: k a, t 1....../2 absorption, t max, C max, t 1/2 elimination, AUC 0-∞, and bioavailability were determined for oral melatonin. C max, t 1/2 elimination, V d, CL and AUC 0-∞ were determined for intravenous melatonin. RESULTS: Twelve male volunteers completed the study. Baseline melatonin plasma levels did not differ...

  2. Melatonin and its precursors scavenge nitric oxide

    Noda, Y.; Mori, A.; Liburdy, R.; Packer, L.

    1998-12-01

    Nitric oxide (NO) scavenging activity of melatonin, N-acetyl-5-hydroxytryptamine, serotonin, 5-hydroxytryptophan and L-tryptophan was examined by the Griess reaction using flow injection analysis. 1-Hydroxy-2-oxo-3-(N-methyl-3-aminopropyl)-3-methyl-1-triazene(NOC-7) was used as NO generator. The Griess reagent stoichiometrically reacts with NO2-, which was converted by a cadmium-copper reduction column from the stable end products of NO oxidation. Except for tryptophan, all the compounds examined scavenged NO in a dose-dependent manner. Melatonin, which has a methoxy group in the 5-position and an acetyl side chain, exhibited the most potent scavenging activity among the compounds tested. Serotonin, N-acetyl-5-hydroxytryptamine, and 5-hydroxytryptophan, respectively, showed moderate scavenging activity compared to melatonin. Tryptophan, which has neither a methoxy nor a hydroxyl group in the 5-position, exhibited the least NO scavenging activity.

  3. Nocturnal Hypertension and Attenuated Nocturnal Blood Pressure Dipping is Common in Pediatric Lupus [version 2; referees: 2 approved, 1 approved with reservations

    J. Fallon Campbell

    2015-11-01

    Full Text Available Hypertension is an important manifestation of systemic lupus erythematosus (SLE but reports of prevalence vary between 20-70% in published reports of adult and pediatric patients. For both children and adults with SLE, the clinical diagnosis and management of hypertension has traditionally been based on guidelines developed for the general population. In clinical trials, the criteria used for defining participants with hypertension are mostly undefined. As a first step towards formally assessing the blood pressure (BP patterns of children diagnosed with SLE, 24-hr ambulatory BP monitoring data was analyzed on clinic patients who presented with prehypertension or stage I hypertension. In this pediatric SLE cohort (n=10, 20% met daytime criteria for a diagnosis of hypertension. Patterns of BP elevation varied widely with white coat, masked, isolated systolic, and diastolic nocturnal hypertension all identified. Nocturnal hypertension was detected in 60% and attenuated nocturnal BP dipping in 90% of both hypertensive and normotensive SLE patients. In SLE patients, the median nighttime systolic and diastolic loads were 25% and 15.5% compared with median daily loads of 12.5% and 11.5%. Daytime and nighttime systolic and diastolic BP load and nocturnal dipping was compared to a control population consisting of 85 non-SLE patients under 21 years old with prehypertension or stage 1 hypertension presenting to hypertension clinic. Median systolic BP dipped 5.3 mmHg in SLE patients compared to 11.9 mmHg in non-lupus (p-value = 0.001. Median diastolic BP dipped 12.9 mmHg versus 18.5 mmHg in non-lupus (p-value = 0.003. Patterns of BP dysregulation in pediatric SLE merit further exploration. Children with or without SLE displaying prehypertensive or stage 1 casual BP measurements had similar rates of hypertension by ambulatory BP monitoring. However, regardless of BP diagnosis, and independent of kidney involvement, there was an increased proportion with

  4. Role of Carnosine and Melatonin in Ameliorating Cardiotoxicity of Titanium Dioxide Nanoparticles in the Rats

    Nouf Al-Rasheed

    2015-08-01

    Full Text Available The aim of this work was to study the possible cardiotoxicity of two different doses of 50 nm nano titanium dioxide (n-TiO2 and the possible modulating effects of the use of two natural antioxidants carnosine and melatonin. The results showed that TiO2- NPs produced deleterious effects on rat cardiac tissue as confirmed by the increased levels of serum myoglobin, troponin-T and CK-MB. Increased levels of serum Inflammatory markers represented by the tumor necrosis factor alpha (TNF-α and Interleukin-6 (IL-6 was also noticed. Caspase3 and IGg were elevated compared to the control group in a dose dependant manner. treatment of the rats with Carnosine or melatonin. along with TiO2- NPs administration significantly improved most of the elevated biochemical markers. It was concluded that the use of Carnosine or melatonin could play a beneficial role against deleterious effects of TiO2- NPs

  5. Melatonin administration reduces inflammatory pain in rats

    Laste G

    2012-09-01

    Full Text Available Gabriela Laste,1–3 Isabel Cristina de Macedo,1,3 Joanna Ripoll Rozisky,1–3 Fernanda Ribeiro da Silva,1,3 Wolnei Caumo,1,2 Iraci LS Torres1–31Laboratório de Farmacologia da Dor, Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, 2Programa de Pós-Graduação em Medicina, Ciências Médicas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; 3Unidade de Experimentação Animal e Grupo de Pesquisa e Pós-Graduação, Hospital de Clínicas de Porto Alegre, Porto Alegre, BrazilAbstract: In view of the broad range of effects attributed to melatonin, this study evaluated its analgesic effect on inflammatory pain induced by complete Freund's adjuvant (CFA in Wistar rats. Inflammation was induced by intradermal CFA injection in the hind paw of all animals, which were then divided into two groups that received either 60 mg/kg of melatonin or vehicle (1% alcohol in saline, intraperitoneally, for three days. The analgesic effect of melatonin was assessed by the hot-plate test, immediately and thereafter at 30, 60, 90, and 120 minutes after the first administration and 24 hours after once-daily administration for 2 more days. After CFA injection, melatonin administration increased withdrawal latency at 60 minutes after the first dose. After the end of treatment, melatonin showed a significant analgesic effect on inflammatory pain. This study paves the way for exploration of how brief courses of treatment could improve this analgesic effect in the late phases of inflammatory pain.Keywords: analgesic response, complete Freund's adjuvant, hot-plate test, inflammation, melatonin, nociception

  6. Effect of melatonin on human nighttime endotoxaemia

    Alamili, Mahdi; Bendtzen, Klaus; Lykkesfeldt, Jens;

    2014-01-01

    BACKGROUND: Endotoxaemia is widely used as an experimental model to study sepsis under controlled conditions. Nighttime endotoxaemia induces a more pronounced inflammatory stress response compared to daytime. Previously, we have shown that melatonin has antioxidative and anti-inflammatory effects...... in inflammatory response to daytime endotoxaemia. Herein, we examined the effect of melatonin in response to human nighttime endotoxaemia. PATIENTS AND METHODS: Twelve healthy male volunteers were enrolled in a randomized, placebo-controlled, double-blinded cross-over trial. Subjects were induced by...... effect on inflammation and oxidative damage induced by nighttime endotoxaemia in contrast to daytime endotoxaemia....

  7. Consequences of nocturnal water loss: a synthesis of regulating factors and implications for capacitance, embolism and use in models.

    Zeppel, M J B; Lewis, J D; Phillips, N G; Tissue, D T

    2014-10-01

    Total daily water use is a key factor influencing the growth of many terrestrial plants, and reflects both day-time and nocturnal water fluxes. However, while nocturnal sap flow (En) and stomatal conductance (gs,n) have been reported across a range of species, ecosystems and microclimatic conditions, the regulation of these fluxes remains poorly understood. Here, we present a framework describing the role of abiotic and biotic factors in regulating En and gs,n highlighting recent developments in this field. Across ecosystems, En and gs,n generally increased with increasing soil water content and vapor pressure deficit, but the interactive effects of these factors and the potential roles of wind speed and other abiotic factors remain unclear. On average, gs,n and En are higher in broad-leaved compared with needle-leaved plants, in C3 compared with C4 plants, and in tropical compared with temperate species. We discuss the impacts of leaf age, elevated [CO2] and refilling of capacitance on night-time water loss, and how nocturnal gs,n may be included in vegetation models. Younger leaves may have higher gs,n than older leaves. Embolism refilling and recharge of capacitance may affect sap flow such that total plant water loss at night may be less than estimated solely from En measurements. Our estimates of gs,n for typical plant functional types, based on the published literature, suggest that nocturnal water loss may be a significant fraction (10-25%) of total daily water loss. Counter-intuitively, elevated [CO2] may increase nocturnal water loss. Assumptions in process-based ecophysiological models and dynamic global vegetation models that gs is zero when solar radiation is zero are likely to be incorrect. Consequently, failure to adequately consider nocturnal water loss may lead to substantial under-estimation of total plant water use and inaccurate estimation of ecosystem level water balance. PMID:25413023

  8. Jet lag: therapeutic use of melatonin and possible application of melatonin analogs.

    Srinivasan, Venkataramanujan; Spence, D Warren; Pandi-Perumal, Seithikurippu R; Trakht, Ilya; Cardinali, Daniel P

    2008-01-01

    Each year millions of travelers undertake long distance flights over one or more continents. These multiple time zone flights produce a constellation of symptoms known as jet lag. Familiar to almost every intercontinental traveler is the experience of fatigue upon arrival in a new time zone, but almost as problematic are a number of other jet lag symptoms. These include reduced alertness, nighttime insomnia, loss of appetite, depressed mood, poor psychomotor coordination and reduced cognitive skills, all symptoms which are closely affected by both the length and direction of travel. The most important jet lag symptoms are due to disruptions to the body's sleep/wake cycle. Clinical and pathophysiological studies also indicate that jet lag can exacerbate existing affective disorders. It has been suggested that dysregulation of melatonin secretion and occurrence of circadian rhythm disturbances may be the common links which underlie jet lag and affective disorders. Largely because of its regulatory effects on the circadian system, melatonin has proven to be highly effective for treating the range of symptoms that accompany transmeridian air travel. Additionally, it has been found to be of value in treating mood disorders like seasonal affective disorder. Melatonin acts on MT(1) and MT(2) melatonin receptors located in the hypothalamic suprachiasmatic nuclei, the site of the body's master circadian clock. Melatonin resets disturbed circadian rhythms and promotes sleep in jet lag and other circadian rhythm sleep disorders, including delayed sleep phase syndrome and shift-work disorder. Although post-flight melatonin administration works efficiently in transmeridian flights across less than 7-8 times zones, in the case longer distances, melatonin should be given by 2-3 days in advance to the flight. To deal with the unwanted side effects which usually accompany this pre-departure treatment (acute soporific and sedative effects in times that may not be wanted), the

  9. Bat predation on nocturnally migrating birds

    Ibáñez, Carlos; Juste, Javier; García-Mudarra, Juan L.; Agirre-Mendi, Pablo T.

    2001-01-01

    Bat predation on birds is a very rare phenomenon in nature. Most documented reports of bird-eating bats refer to tropical bats that occasionally capture resting birds. Millions of small birds concentrate and cross over the world's temperate regions during migration, mainly at night, but no nocturnal predators are known to benefit from this enormous food resource. An analysis of 14,000 fecal pellets of the greater noctule bat (Nyctalus lasiopterus) reveals that this...

  10. Unrecognised nocturnal hypoglycaemia masquerading as senile dementia.

    Ramasamy, R.

    1983-01-01

    A 70-year-old woman with insulin dependent diabetes mellitus presented with symptoms suggestive of senile dementia. Outpatient assessment failed to reveal poor diabetic control with frequent nocturnal hypoglycaemia. Eventual appreciation of the poor control resulted in several failed attempts at improving therapy with various subcutaneous insulin regimes. Intramuscular and intravenous routes produced acceptable blood glucose levels with striking reversal of the patient's symptoms. The possibl...

  11. Correlations between behavior, memory, sleep-wake and melatonin in Williams-Beuren syndrome.

    Santoro, Stella Donadon; Giacheti, Celia Maria; Rossi, Natalia Freitas; Campos, Leila Maria Guissoni; Pinato, Luciana

    2016-05-15

    variations in aMT6s levels. In addition, there was a negative correlation between the scores of auditory memory and the total score of sleep disorders and between the DIMS and nocturnal aMT6s content. In conclusion, in the present study, individuals with WBS showed a high frequency of behavioral and memory problems, sleep disturbances and no rhythm variation in aMT6s levels. The low melatonin content may be related with sleep disorders in this population, which, in turn, can have an adverse effect on specific cognitive skills such as memory. PMID:26976740

  12. Melatonin decreases the expression of inflammation and apoptosis markers in the lung of a senescence-accelerated mice model.

    Puig, Ángela; Rancan, Lisa; Paredes, Sergio D; Carrasco, Adrián; Escames, Germaine; Vara, Elena; Tresguerres, Jesús A F

    2016-03-01

    Aging is associated with an increase in oxidative stress and inflammation. The aging lung is particularly affected since it is continuously exposed to environmental oxidants while antioxidant machinery weakens with age. Melatonin, a free radical scavenger, counteracts inflammation and apoptosis in healthy cells from several tissues. Its effects on the aging lung are, however, not yet fully understood. This study aimed to investigate the effect of chronic administration of melatonin on the expression of inflammation markers (TNF-α, IL-1β, NFκB2, HO-1) and apoptosis parameters (BAD, BAX, AIF) in the lung tissue of male senescence-accelerated prone mice (SAMP8). In addition, RNA oxidative damage, as the formation of 8-hydroxyguanosine (8-OHG), was also evaluated. Young and old animals, aged 2 and 10 months respectively, were divided into 4 groups: untreated young, untreated old, old mice treated with 1mg/kg/day melatonin, and old animals treated with 10mg/kg/day melatonin. Untreated young and old male senescence accelerated resistant mice (SAMR1) were used as controls. After 30 days of treatment, animals were sacrificed. Lungs were collected and immediately frozen in liquid nitrogen. mRNA and protein expressions were measured by RT-PCR and Western blotting, respectively. Levels of 8-OHG were quantified by ELISA. Mean values were analyzed using ANOVA. Old nontreated SAMP8 animals showed increased (paging-derived inflammation (paging, the effect being counteracted with melatonin (pAging also caused a significant elevation (panimals treated with melatonin (paging lungs, exerting a protective effect on age-induced damage. PMID:26656745

  13. Melatonin as a possible antidote to UV radiation induced cutaneous damages and immune-suppression: An overview.

    Goswami, Soumik; Haldar, Chandana

    2015-12-01

    The sun rays brings along the ultraviolet radiations (UVRs) which prove deleterious for living organisms. The UVR is a known mutagen and is the prime cause of skin carcinomas. UVR causes acute oxidative stress and this in turn deteriorates other physiological functions. Inflammatory conditions and elevation of pro-inflammatory molecules are also associated with UVR mediated cellular damages. The inflammatory conditions can secondarily trigger the generation of free radicals and this act cumulatively in further deterioration of tissue homeostasis. Photoimmunologists have also related UVR to the suppression of not only cutaneous but also systemic immunity by different mechanisms. Some researchers have proposed the use of various plant products as antioxidants against UVR induced oxidative imbalances but Melatonin is gaining rapid interest as a product that can be utilized to delineate the pathological effects of UVR since it is an established antioxidant. Besides the antioxidative nature, the capacity of melatonin to attenuate apoptosis and more importantly the efficacy of its metabolites to further aid in the detoxification of free radicals have made it a key player to be utilized against UVR mediated aggravated conditions. However, there is need for further extensive investigation to speculate melatonin as an antidote to UVR. Although too early to prescribe melatonin as a clinical remedy, the hormone can be integrated into dermal formulations or oral supplements to prevent the ever increasing incidences of skin cancers due to the prevalence of the UVR on the surface of the earth. The present review focuses and substantiates the work by different photo-biologists demonstrating the protective effects of melatonin and its metabolites against solar UVR - Melatonin as a possible antidote to UV radiation induced cutaneous damages and immune-suppression: an overview. J Photochem Photobiol B. PMID:26496791

  14. Caffeine raises the serum melatonin level in healthy subjects: an indication of melatonin metabolism by cytochrome P450(CYP)1A2.

    Ursing, C; Wikner, J; Brismar, K; Röjdmark, S

    2003-05-01

    Caffeine is metabolized in the liver by cytochrome P450(CYP)1A2. Recent findings imply that this enzyme may also be of importance for the metabolism of human melatonin (MT). If caffeine and MT are metabolized by the same enzyme, one may expect to find different serum MT levels after ingestion of coffee compared with placebo. Although coffee is consumed by people all over the world, few studies have focused on whether caffeine actually affects serum MT levels in normal subjects. We decided to study that particular topic. For that purpose 12 healthy individuals were tested on two occasions, one week apart. On one of these occasions they were given a capsule containing 200 mg caffeine in the evening. On the other, they received placebo. The experimental order was randomized. Serum MT levels were determined every second hour between 22:00 h and 08:00 h, and the melatonin areas under the curve (MT-AUCs) were calculated. After caffeine the serum MT level rose from 0.09 +/- 0.03 nmol/l at 22:00 h to 0.48 +/- 0.07 nmol/l at 04:00 h. The corresponding rise after placebo was less prominent (from 0.06 +/- 0.01 to 0.35 +/- 0.06 nmol/l). This was reflected by the MT-AUC which was 32% larger after ingestion of caffeine compared with placebo (MT-AUC(caffeine) 3.16 +/- 0.44 nmol/l x h vs MT-AUC(placebo) 2.39 +/- 0.40 nmol/l x h; p coffee, augments the nocturnal serum MT level, which in turn supports the notion that cytochrome P450(CYP)1A2 is involved in the hepatic metabolism of human MT. PMID:12906366

  15. The research of melatonin in hypoxic-ischemic encephalopathy

    Objective: To elucidate the function of melatonin in the pathogenesis and the prognosis of hypoxic-ischemic encephalopathy (HIE) and provide the pathophysiology basis for therapying HIE with melatonin. Methods: The level of plasma melatonin of twenty normal term infants and twenty modest HIE and twenty middle-severity HIE in their acute phase and recovery phase were assayed respectively with radioimmunoassay (RIA). Then compare the difference of the melatonin level among these neonates. Results: (1) For modest HIE, the melatonin level was higher than that in the normal in the acute phase and there was no difference to the normal in the recovery phase. (2) There was no difference between the melatonin level in middle-severity HIE in the acute phase and that in the normal, but in the recovery phase it was higher than that in the normal. (3) For modest HIE, the melatonin level in acute phase was higher than that in the recovery phase, but for middle-severity HIE, it was adverse. (4) In the acute phase, the level in modest HIE was higher than that in the middle-severity HIE, but on the contrary in the recovery phase. Conclusion: Melatonin have protection action on HIE. The prognosis of modest HIE neonates with rising melatonin level in the acute phase is better than that with lower melatonin level of middle-severity HIE. (authors)

  16. Melatonin attenuates postharvest physiological deterioration of cassava storage roots.

    Ma, Qiuxiang; Zhang, Ting; Zhang, Peng; Wang, Zhen-Yu

    2016-05-01

    Melatonin reportedly increases abiotic and biotic stress tolerance in plants, but information on its in vivo effects during postharvest physiological deterioration (PPD) in cassava is limited. In this study, we investigated the effect of melatonin in regulating cassava PPD. Treatment with 500 mg/L melatonin significantly delayed cassava PPD and reduced the accumulation of hydrogen peroxide (H2 O2 ) while increasing the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR), but not ascorbate peroxidase (APX). Transcript analysis further showed that expression of copper/zinc SOD (MeCu/ZnSOD), MeCAT1, glutathione peroxidase (MeGPX), peroxidase 3 (MePX3), and glutathione S-transferases (MeGST) was higher in cassava roots sliced treated with 500 mg/L melatonin than in those not exposed to exogenous melatonin. These data demonstrate that melatonin delays cassava PPD by directly or indirectly maintaining homoeostasis of cellular reactive oxygen species (ROS). We also found that accumulation of endogenous melatonin and the transcript levels of melatonin biosynthesis genes changed dynamically during the PPD process. This finding suggested that endogenous melatonin acts as a signal modulator for maintaining cassava PPD progression and that manipulation of melatonin biosynthesis genes through genetic engineering might prevent cassava root deterioration. PMID:26989849

  17. Shedding light on light: benefits of anthropogenic illumination to a nocturnally foraging shorebird.

    Dwyer, Ross G; Bearhop, Stuart; Campbell, Hamish A; Bryant, David M

    2013-03-01

    Intertidal habitats provide important feeding areas for migratory shorebirds. Anthropogenic developments along coasts can increase ambient light levels at night across adjacent inter-tidal zones. Here, we report the effects of elevated nocturnal light levels upon the foraging strategy of a migratory shorebird (common redshank Tringa totanus) overwintering on an industrialised estuary in Northern Europe. To monitor behaviour across the full intertidal area, individuals were located by day and night using VHF transmitters, and foraging behaviour was inferred from inbuilt posture sensors. Natural light was scored using moon-phase and cloud cover information and nocturnal artificial light levels were obtained using geo-referenced DMSP/OLS night-time satellite imagery at a 1-km resolution. Under high illumination levels, the commonest and apparently preferred foraging behaviour was sight-based. Conversely, birds feeding in areas with low levels of artificial light had an elevated foraging time and fed by touch, but switched to visual rather than tactile foraging behaviour on bright moonlit nights in the absence of cloud cover. Individuals occupying areas which were illuminated continuously by lighting from a large petrochemical complex invariably exhibited a visually based foraging behaviour independently of lunar phase and cloud cover. We show that ambient light levels affect the timing and distribution of foraging opportunities for redshank. We argue that light emitted from an industrial complex improved nocturnal visibility. This allowed sight-based foraging in place of tactile foraging, implying both a preference for sight-feeding and enhanced night-time foraging opportunities under these conditions. The study highlights the value of integrating remotely sensed data and telemetry techniques to assess the effect of anthropogenic change upon nocturnal behaviour and habitat use. PMID:23190422

  18. Melatonin based therapies for delirium and dementia.

    Alagiakrishnan, Kannayiram

    2016-05-01

    Melatonin levels have been shown to decline with aging. Melatonin and its analogs in addition to their effect on sleep promotion, has been shown to have multiple pleiotropic effects. It can also help with neuroprotection through different mechanisms. Evidence in animal and human studies suggests that low levels of melatonin have been linked to delirium, mild cognitive impairment, dementia, and with certain behavioral problems. Recent clinical trials have showed that both melatonin and its analogs may be useful in the prevention, treatment of delirium, and the management of dementia. These medications seem to have the advantage of less side effects and better safety profile when compared to antipsychotics and sedatives like benzodiazepines. These medications are available over the counter in North America, Europe, and Asia, and some of these medications are approved by FDA. This manuscript will discuss the promising role of these melatonergic medications alone or in combination with other medications for the management of Geriatric Psychiatric diseases like delirium and dementia. PMID:27355332

  19. The Impact of Melatonin in Research

    Elena Maria Varoni

    2016-02-01

    Full Text Available Citation indexes represent helpful tools for evaluating the impact of articles on research. The aim of this study was to obtain the top-100 ranking of the most cited papers on melatonin, a relevant neurohormone mainly involved in phase-adjusting the biological clock and with certain sleep-promoting capability. An article search was carried out on the Institute for Scientific Information (ISI Web of Science platform. Numbers of citations, names of authors, journals and their 2014-impact factor, year of publication, and experimental designs of studies were recorded. The ranking of the 100-most cited articles on melatonin research (up to February 2016 revealed a citation range from 1623 to 310. Narrative reviews/expert opinions were the most frequently cited articles, while the main research topics were oxidative stress, sleep physiology, reproduction, circadian rhythms and melatonin receptors. This study represents the first detailed analysis of the 100 top-cited articles published in the field of melatonin research, showing its impact and relevance in the biomedical field.

  20. The Impact of Melatonin in Research.

    Varoni, Elena Maria; Soru, Clelia; Pluchino, Roberta; Intra, Chiara; Iriti, Marcello

    2016-01-01

    Citation indexes represent helpful tools for evaluating the impact of articles on research. The aim of this study was to obtain the top-100 ranking of the most cited papers on melatonin, a relevant neurohormone mainly involved in phase-adjusting the biological clock and with certain sleep-promoting capability. An article search was carried out on the Institute for Scientific Information (ISI) Web of Science platform. Numbers of citations, names of authors, journals and their 2014-impact factor, year of publication, and experimental designs of studies were recorded. The ranking of the 100-most cited articles on melatonin research (up to February 2016) revealed a citation range from 1623 to 310. Narrative reviews/expert opinions were the most frequently cited articles, while the main research topics were oxidative stress, sleep physiology, reproduction, circadian rhythms and melatonin receptors. This study represents the first detailed analysis of the 100 top-cited articles published in the field of melatonin research, showing its impact and relevance in the biomedical field. PMID:26907237

  1. Microorganisms for the production of melatonin

    2013-01-01

    Recombinant microbial cells and methods for producing melatonin and related compounds using such cells are described. More specifically, the recombinant microbial cell may comprise exogenous genes encoding one or more of an L-tryptophan hydroxylase, a 5-hydroxy-L- tryptophan decarboxylyase, a...

  2. EFFECTS OF MELATONIN ON MORPHINE DEPENDENCE

    WEIYiming; YUChangxi; XIEJieming

    2004-01-01

    AIM: To study the effects of melatonin (MT) on morphine dependence. METHODS: Morphine hydrochloride was administered (sc) to mice for 8 days to establish morphine dependence model. Withdrawal syndromes were precipitated by naloxone (ip). Different doses of MT were given either before or after the model established. Isolated guinea-pig ileums

  3. Short-term air temperature on a regional scale and its estimation with a nocturnal cooling model

    Accuracy of spatial estimation of air temperatures can be very poor for a short term temperature. The objective of this paper is to study feasibility of the regional estimation of air temperatures with a nocturnal cooling model, which was proposed by Kondo & Mori (1982) to describe nocturnal cooling rate with wind speed and site-specific parameters. First, relationships between elevation and air temperatures within diurnal cycles were addressed at 27 monitoring points across a region of 110km×100km in central Japan. The weather data were obtained from the Automated Meteorological Data Acquisition System. The results showed that air temperature in the evenings was linearly related to the elevation above sea level with little perturbations from the weather, wind speed and topography. In contrast, minimum air temperature in the mornings and nocturnal cooling rate were greatly influenced by the above factors. Furthermore, in a complex terrain, the morning air temperature and cooling rate were unrelated to those at nearby points. Therefore, the two temperature traits may not be accurately estimated by using spatial interpolation. Second, two parameters (a & b) of the nocturnal cooling model were determined for each of the 27 monitoring points, and were related to topographical features of the points. Indexes of surface flatness (Sidx), cubical measure by a concavo-convex space (Cidx) and steepness (Ridx) on the level surface at observation were defined and calculated for each point using elevations of the grid points of the Digital National Land Information. The parameter b, which represents thermal conditions and accumulation of cold air, was related to Sidx and Cidx. The parameter a, which represents the extent of air mixing, was related to Ridx. The short-term air temperatures could therefore be estimated on a regional basis with the nocturnal cooling model, whose parameters are determined with the topographical indexes. (author)

  4. Melatonin in Epilepsy: A New Mathematical Model of Diurnal Secretion

    Kijonka, Marek; Pęcka, Marcin; Sokół, Maria

    2016-01-01

    Purpose. The main objective of the study was to create a mathematical model that describes the melatonin circadian secretion and, then the functionality of the model was tested by a comparison of the melatonin secretions in children with and without epilepsy. Material and Methods. The patients were divided into the epilepsy group (EG, n = 52) and the comparison group (CG, n = 30). The melatonin level was assessed by a radioimmunoassay method. The diurnal melatonin secretion was described using a nonlinear least squares method. Spearman's rank correlation coefficient was chosen to estimate the dependence of the acquired data. The model reproduces blood concentration profiles and its parameters were statistically analyzed using the Mann-Whitney-Wilcoxon test and logistic regression. Results. The correlation analysis performed for the EG and CG groups showed moderate correlations between age and the melatonin secretion model parameters. Patients with epilepsy are characterized by an increased phase shift of melatonin release. PMID:27478439

  5. Advances in Melatonin and Its Functions in Plants

    Na ZHANG; Haijun ZHANG; Rongchao YANG; Yunyu HUANG; Yangdong GUO

    2012-01-01

    Abstract Melatonin (N-acetyi-5-methoxytryptamine) is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has been observed that melatonin is widely existed in higher plants while there have no enough studies on functions of melatonin in plants. Researches have already indicated that the possible functions of melatonin in plants include regulating photoperiod, participating in growth regulation, clearing active oxygen, and promoting activity of antioxidase. General reviews upon functions of melatonin in plants are made upon experiments in recent years. We fo-cus on the demonstrated and predicted biological functions of melatonin in plants to bring researchers up to date on this field. The weakness in present studies and the main research directions are also pointed out.

  6. Fundamental Issues of Melatonin-Mediated Stress Signaling in Plants.

    Shi, Haitao; Chen, Keli; Wei, Yunxie; He, Chaozu

    2016-01-01

    As a widely known hormone in animals, melatonin (N-acetyl-5-methoxytryptamine) has been more and more popular research topic in various aspects of plants. To summarize the these recent advances, this review focuses on the regulatory effects of melatonin in plant response to multiple abiotic stresses including salt, drought, cold, heat and oxidative stresses and biotic stress such as pathogen infection. We highlight the changes of endogenous melatonin levels under stress conditions, and the extensive metabolome, transcriptome, and proteome reprogramming by exogenous melatonin application. Moreover, melatonin-mediated stress signaling and underlying mechanism in plants are extensively discussed. Much more is needed to further study in detail the mechanisms of melatonin-mediated stress signaling in plants. PMID:27512404

  7. Intracoronary and systemic melatonin to patients with acute myocardial infarction

    Halladin, Natalie L; Busch, Sarah Ekeløf; Jensen, Svend Eggert;

    2014-01-01

    reperfusion. The endogenous hormone, melatonin, works as an antioxidant and could potentially minimise the ischaemia-reperfusion injury. Given intracoronarily, it enables melatonin to work directly at the site of reperfusion. We wish to test if melatonin, as an antioxidant, can minimise the reperfusion injury...... Myocardial Salvage Index assessed by cardiovascular magnetic resonance imaging on day 4 (± 1) after pPCI. The secondary end-points are high-sensitivity troponin, creatinekinase myocardial band and clinical events. CONCLUSION: The aim of the IMPACT trial is to evaluate the effect of melatonin on reperfusion...... injuries following pPCI. Owing to its relatively non-toxic profile, melatonin is an easily implementable drug in the clinical setting, and melatonin has the potential to reduce morbidity in patients with AMI. FUNDING: This study received no financial support from the industry. TRIAL REGISTRATION: www...

  8. Increased melatonin levels in aqueous humor of patients with proliferative retinopathy in type 2 diabetes mellitus

    Aydin, Erdinc; Sahin, Semsettin

    2016-01-01

    AIM To report the association between melatonin levels in aqueous humor and serum, and diabetic retinopathy (DR) grade in type 2 diabetic patients. METHODS Aqueous humor and plasma samples from 26 patients with DR (in nonproliferative and proliferative stages) and 14 control subjects were collected during cataract surgery after 6 p.m. Melatonin concentrations were determined using an enzyme-linked immunosorbent assay (ELISA). RESULTS Melatonin levels were significantly higher in the aqueous humor of patients with proliferative diabetic retinopathy (PDR) [18.57±2.67 pg/mL (range 15.20-23.06) vs 13.63±2.71 pg/mL (range 10.20-20.20), P=0.0001], but not in those with nonproliferative retinopathy (NPDR) [13.79±2.56 pg/mL (range 9.80-20.10) vs 13.63±2.71 pg/mL (range 10.20-20.20), P=0.961] compared to controls. There was decrement in the plasma melatonin level of patients with PDR, but no significant differences between the plasma melatonin levels of the study groups [5.37±1.74 pg/mL (range 2.85-8.65) vs 6.11±1.90 pg/mL (range 3.13-9.41), P=0.293], or between control and DR groups [NPDR 6.11±1.90 pg/mL (range 3.13-9.41) vs control 6.15±1.91 pg/mL (range 2.18-9.86); PDR (5.37±1.74 pg/mL (range 2.85-8.65) vs control 6.15±1.91 pg/mL (range 2.18-9.86), P=0.808, P=0.264]. CONCLUSION Elevated melatonin levels in aqueous humor in PDR may indicate the level to be associated with DR severity. PMID:27275429

  9. Treatment with beta-adrenoceptor blockers reduces plasma melatonin concentration.

    Cowen, P J; Bevan, J. S.; Gosden, B; Elliott, S A

    1985-01-01

    In treated hypertensive patients plasma melatonin levels were lower in subjects receiving beta-adrenoceptor blockers than those treated with diuretics. Melatonin concentrations in middle-aged and young control subjects were similar to each other and to those of the diuretic-treated patients. The results suggest that treatment with beta-adrenoceptor blockers causes a persistent reduction in plasma melatonin but it is unclear if this finding has clinical implications.

  10. Pharmacokinetics of high-dose intravenous melatonin in humans

    Andersen, Lars P H; Werner, Mads U; Rosenkilde, Mette Marie;

    2016-01-01

    This crossover study investigated the pharmacokinetics and adverse effects of high-dose intravenous melatonin. Volunteers participated in 3 identical study sessions, receiving an intravenous bolus of 10 mg melatonin, 100 mg melatonin, and placebo. Blood samples were collected at baseline and 0, 60......, 120, 180, 240, 300, 360, and 420 minutes after the bolus. Quantitative determination of plasma melatonin concentrations was performed using a radioimmunoassay technique. Pharmacokinetic parameters were estimated by a compartmental pharmacokinetic analysis. Adverse effects included assessments of...

  11. Melatonin is rhythmic in newborn seals exposed to continuous light.

    Aarseth, J J; Van't Hof, T J; Stokkan, K-A

    2003-02-01

    We have investigated the effect of continuous light and darkness on plasma levels of melatonin in relation to the extremely large and active pineal gland typically found in newborn seals. Plasma levels of melatonin in captive newborn harp (Phoca groenlandica) and hooded seals (Cystophora cristata) were generally extremely high, with peak concentrations ranging from 0.8 ng/ml to 62.3 ng/ml. Moreover, plasma melatonin showed a similar, pronounced rhythmicity, both outdoors under natural light conditions (hooded seal only) and indoors under either 30 h of continuous light (490 lux) or 30 h of darkness (0 lux). In all animals, the melatonin rhythm was closely associated with the outdoor light-dark cycle. We suggest that the melatonin rhythmicity in newborn seals is mainly under circadian control and that it originates by maternal influence in the foetus. Daytime plasma concentrations of melatonin were also measured in foetal hooded seals and their mothers. The foetal melatonin level was similar to daytime levels in newborns and was about five times higher than in their mothers, which indicates a significant flow of foetal melatonin to the mother. We speculate that the large pineal gland and high melatonin levels in the newborn seals are temporary consequences of a foetal strategy to affect the maternal blood supply during diving. PMID:12592441

  12. Role of melatonin in Alzheimer-like neurodegeneration

    Jian-zhi WANG; Ze-fen WANG

    2006-01-01

    Alzheimer disease (AD), an age-related neurodegenerative disorder with progressive loss of memory and deterioration of comprehensive cognition, is characterized by extracellular senile plaques of aggregated β-amyloid (Aβ), and intracellular neurofibrillary tangles that contain hyperphosphorylated tau protein. Recent studies showed that melatonin, an indoleamine secreted by the pineal gland, may play an important role in aging and AD as an antioxidant and neuroprotector.Melatonin decreases during aging and patients with AD have a more profound reduction in this hormone. Data from clinical trials indicate that melatonin supplementation improves sleep, ameliorates sundowning, and slows down the progression of cognitive impairment in Alzheimer's patients. Melatonin efficiently protects neuronal cells from Aβ-mediated toxicity via antioxidant and anti-amyloid properties: it not only inhibits Aβ generation, but also arrests the formation of amyloid fibrils by a structure-dependent interaction with Aβ. Our recent studies have demonstrated that melatonin efficiently attenuates Alzheimer-like tau hyperphosphorylation. Although the exact mechanism is still not fully understood,a direct regulatory influence of melatonin on the activities of protein kinases and protein phosphatases is proposed. Additionally, melatonin also plays a role in protecting cholinergic neurons and in anti-inflammation. Here, the neuroprotective effects of melatonin and the underlying mechanisms by which it exerts its effects are reviewed. The capacity of melatonin to prevent or ameliorate tau and Aβ pathology further enhances its potential in the prevention or treatment of AD.

  13. Oxytocin and prolactin release after hypertonic saline administration in melatonin-treated male Syrian hamsters

    Juszczak, M.; Steger, R.W.; Fadden, C.; Bartke, A. [Southern Illinois Univ., Carbondale, IL (United States)

    1996-12-31

    The aim of the present investigations was to examine the effects of melatonin (Mel) on oxytocin (OT) release under conditions of osmotic stimulation, brought about by hypertonic saline administration, as well as to determine whether osmotically stimulated OT release in Mel-treated Syrian hamster is associated with alterations in the release of prolactin (PRL) and in norepinephrine (NE) and dopamine (DA) content in the hypothalamus. In both Mel- and vehicle-treated hamsters, injection of hypertonic saline was followed by a significant decrease in OT content in the pituitary neurointermediate lobe (NIL) and elevation of plasma OT and PRL levels. Melatonin injections had no significant affect on NIL OT content in either isotonic- or hypertonic-saline treated animals. Pretreatment with Mel did not alter plasma OT or PRL levels in isotonic saline-injected animals. However, Mel facilitated the release of OT, but prevented the release of PRL after hypertonic saline administration. Melatonin treatment reduced hypothalamic NE content (but not that of DA) in isotonic-saline treated animals. After osmotic stimulation, hypothalamic content of NE and DA was significantly lower in Mel-treated than in vehicle-treated animals. Data from the present study suggest that the osmotically-stimulated release of OT and PRL seems to be related to the activation of noradrenergic rather than dopaminergic transmission. Both dopaminergic and noradrenergic transmission may be, however, involved in mediating the effects of Mel on the osmotically-activated OT and PRL release. (author). 48 refs, 3 figs.

  14. Interleukin-1 β Modulates Melatonin Secretion in Ovine Pineal Gland: Ex Vivo Study

    A. P. Herman

    2015-01-01

    Full Text Available The study was designed to determine the effect of proinflammatory cytokine, interleukin- (IL- 1β, on melatonin release and expression enzymes essential for this hormone synthesis: arylalkylamine-N-acetyltransferase (AA-NAT and hydroxyindole-O-methyltransferase (HIOMT in ovine pineal gland, taking into account the immune status of animals before sacrificing. Ewes were injected by lipopolysaccharide (LPS; 400 ng/kg or saline, two hours after sunset during short day period (December. Animals were euthanized three hours after the injection. Next, the pineal glands were collected and divided into four explants. The explants were incubated with (1 medium 199 (control explants, (2 norepinephrine (NE; 10 µM, (3 IL-1β (75 pg/mL, or (4 NE + IL-1β. It was found that IL-1β abolished (P<0.05 NE-induced increase in melatonin release. Treatment with IL-1β also reduced (P<0.05 expression of AA-NAT enzyme compared to NE-treated explants. There was no effect of NE or IL-1β treatment on gene expression of HIOMT; however, the pineal fragments isolated from LPS-treated animals were characterized by elevated (P<0.05 expression of HIOMT mRNA and protein compared to the explants from saline-treated ewes. Our study proves that IL-1β suppresses melatonin secretion and its action seems to be targeted on the reduction of pineal AA-NAT protein expression.

  15. Green Light for Nocturnally Migrating Birds

    Marcel R. Wernand

    2008-12-01

    Full Text Available The nighttime sky is increasingly illuminated by artificial light sources. Although this ecological light pollution is damaging ecosystems throughout the world, the topic has received relatively little attention. Many nocturnally migrating birds die or lose a large amount of their energy reserves during migration as a result of encountering artificial light sources. This happens, for instance, in the North Sea, where large numbers of nocturnally migrating birds are attracted to the many offshore platforms. Our aim is to develop bird-friendly artificial lighting that meets human demands for safety but does not attract and disorient birds. Our current working hypothesis is that artificial light interferes with the magnetic compass of the birds, one of several orientation mechanisms and especially important during overcast nights. Laboratory experiments have shown the magnetic compass to be wavelength dependent: migratory birds require light from the blue-green part of the spectrum for magnetic compass orientation, whereas red light (visible long-wavelength disrupts magnetic orientation. We designed a field study to test if and how changing light color influenced migrating birds under field conditions. We found that nocturnally migrating birds were disoriented and attracted by red and white light (containing visible long-wavelength radiation, whereas they were clearly less disoriented by blue and green light (containing less or no visible long-wavelength radiation. This was especially the case on overcast nights. Our results clearly open perspective for the development of bird-friendly artificial lighting by manipulating wavelength characteristics. Preliminary results with an experimentally developed bird-friendly light source on an offshore platform are promising. What needs to be investigated is the impact of bird-friendly light on other organisms than birds.

  16. Anticonvulsant activity of melatonin, but not melatonin receptor agonists Neu-P11 and Neu-P67, in mice.

    Mosińska, Paula; Socała, Katarzyna; Nieoczym, Dorota; Laudon, Moshe; Storr, Martin; Fichna, Jakub; Wlaź, Piotr

    2016-07-01

    The anticonvulsant activity of melatonin (MLT) have been tested in several in vivo models and against different convulsive stimuli. Although MLT exerts high affinity towards melatonin receptors (MTs), the potential usefulness in the treatment of epilepsy is limited mainly due to its short half-life. Therefore, the purpose of the present study was to compare the anticonvulsant properties of novel MT agonists Neu-P11 and Neu-P67 with MLT in mice. The anticonvulsant activity of tested compounds was evaluated in pentylenetetrazole-(PTZ) and electrically-induced convulsions. The effect of studied compounds on motor coordination and skeletal muscular strength in mice was assessed in the chimney test and grip test, respectively. The locomotor activity after administration of the tested compounds was also evaluated. In the MEST and 6Hz tests, only MLT (50 and 100mg/kg, i.p.) significantly increased the seizure threshold. The i.p. administration of MLT (100mg/kg) and Neu-P67 (200mg/kg) resulted in a significantly elevated PTZ seizure threshold for forelimbs tonus. The compounds did not affect muscle strength. No alterations in motor coordination were noted. However, the locomotor activity was significantly decreased after administration of all tested compounds. Our study confirms the anticonvulsant potency of MLT and shows that novel synthetic MT agonists Neu-P11 and Neu-P67 have no effect on epileptic seizures in mice. Our data suggest that the activation of MT can be used in the treatment of seizures, but further pharmacological characterization is needed to understand the anticonvulsant activity of MLT and to design efficient MT-targeting antiepileptic drugs. PMID:27016427

  17. Extended Driving Impairs Nocturnal Driving Performances

    Patricia Sagaspe; Jacques Taillard; Torbjorn Akerstedt; Virginie Bayon; Stéphane Espié; Guillaume Chaumet; Bernard Bioulac; Pierre Philip

    2008-01-01

    Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3-5 am, 1-5 am and 9 pm-5 am) on open highway. Fourteen young healthy men (mean age [+/-SD] = 23.4 [+/-1.7] years)...

  18. Nocturnal enuresis among primary school children

    Hasan Mohamed Aljefri; Omer Abdullah Basurreh; Faisel Yunus; Amen Ahmed Bawazir

    2013-01-01

    To determine the prevalence and personal and family risk factors for nocturnal enuresis (NE) among primary school children in Al-Mukalla City, Yemen, we conducted a cross-sectional survey using a self-administered, three-part structured questionnaire involving 832 school children aged 6 - 15 years between 2007 and 2008. We assessed participants′ socio-demographic factors, family characteristics and factors related to the presence of NE. The mean age of the children was 11.5 (±2.7) years. The ...

  19. Extended Driving Impairs Nocturnal Driving Performances

    SAGASPE, Patricia; Taillard, Jacques; Åkerstedt, Torbjorn; BAYON, Virginie; Espié, Stéphane; Chaumet, Guillaume; Bioulac, Bernard; Philip, Pierre

    2008-01-01

    Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3–5am, 1–5am and 9pm–5am) on open highway. Fourteen young healthy men (mean age [±SD] = 23.4 [±1.7] years) partici...

  20. Melatonin enhances mitochondrial ATP synthesis, reduces reactive oxygen species formation, and mediates translocation of the nuclear erythroid 2-related factor 2 resulting in activation of phase-2 antioxidant enzymes (γ-GCS, HO-1, NQO1) in ultraviolet radiation-treated normal human epidermal keratinocytes (NHEK).

    Kleszczyński, Konrad; Zillikens, Detlef; Fischer, Tobias W

    2016-09-01

    Melatonin is an ubiquitous molecule with a variety of functions including potent antioxidative properties. Due to its lipophilic character, it easily crosses cellular and intracellular membranes and reaches all subcellular organelles. Because of its ability to scavenge free radicals, melatonin protects against oxidative stress, for example, induced by ultraviolet radiation (UVR). Here, we investigated, in a dose-dependent (0, 10, 25, and 50 mJ/cm(2) ) and time-dependent (0, 4, 24, 48 hr post-UVR) manner, whether melatonin prevents the UVR-mediated alterations in ATP synthesis and the generation of reactive oxygen species (ROS) in normal human epidermal keratinocytes (NHEK). Additionally, we evaluated the molecular mechanism of action of melatonin with regard to activation of phase-2 antioxidative enzymes via nuclear erythroid 2-related factor (Nrf2). We found that (i) melatonin counteracted UVR-induced alterations in the ATP synthesis and reduced free radical formation; (ii) melatonin induced the translocation of Nrf2 transcription factor from the cytosol into the nucleus resulting in, (iii) melatonin enhanced gene expression of phase-2 antioxidative enzymes including γ-glutamylcysteine synthetase (γ-GCS), heme oxygenase-1 (HO-1), and NADPH: quinone dehydrogenase-1 (NQO1) representing an elevated antioxidative response of keratinocytes. These results suggest that melatonin not only directly scavenges ROS, but also significantly induces the activation of phase-2 antioxidative enzymes via the Nrf2 pathway uncovering a new action mechanism that supports the ability of keratinocytes to protect themselves from UVR-mediated oxidative stress. PMID:27117941

  1. Nocturnal hypoxaemia and hypercapnia in children with neuromuscular disorders.

    Bersanini, Chiara; Khirani, Sonia; Ramirez, Adriana; Lofaso, Frédéric; Aubertin, Guillaume; Beydon, Nicole; Mayer, Michèle; Maincent, Kim; Boulé, Michèle; Fauroux, Brigitte

    2012-05-01

    The aim of the study was to identify daytime predictors of nocturnal gas exchange anomalies in children with neuromuscular disease (NMD) and normal daytime gas exchange. Lung function tests, respiratory muscle evaluation and nocturnal gas exchange were obtained as part of routine evaluation. We included 52 consecutive children with Duchenne muscular dystrophy (n = 20), spinal muscular atrophy (n = 10) and other NMD (n = 22). 20 patients had nocturnal hypoxaemia, defined as minimal arterial oxygen saturation measured by pulse oximetry (S(p,O(2))) carbon dioxide tension (P(tc,CO(2))) >50 mmHg for ≥ 2% of night time. Forced vital capacity and helium functional residual capacity correlated with minimal nocturnal S(p,O(2)) (p = 0.009 and p = 0.01, respectively). Daytime pH correlated negatively with maximal nocturnal P(tc,CO(2)) (p=0.005) and daytime arterial carbon dioxide tension (P(a,CO(2))) correlated with the percentage of time with a P(tc,CO(2)) >50 mmHg (p = 0.02). Sniff nasal inspiratory pressure correlated with minimal nocturnal S(p,O(2)) (p = 0.02). Daytime P(a,CO(2)) was a weak predictor of nocturnal hypercapnia (sensitivity 80%; specificity 57%). Daytime lung function and respiratory muscle parameters correlate poorly with nocturnal hypoxaemia and hypercapnia in children with NMD and normal daytime gas exchange, which necessitates more systematic sleep studies in these children. PMID:22135279

  2. Adherence to Bergmann's rule by lizards may depend on thermoregulatory mode: support from a nocturnal gecko.

    Penniket, Sophie; Cree, Alison

    2015-06-01

    Bergmann's rule predicts an increase in body size with decreasing environmental temperature; however, the converse pattern has been found in the majority of lizards studied to date. For these ectotherms, small body size may provide thermal benefits (rapid heat uptake when basking), which would be highly advantageous in cold environments. Yet such an advantage may not exist in nocturnal lizards (which do not avidly bask), in which Bergmann's rule has not been closely studied. We have examined whether the body size of a primarily nocturnal gecko, Woodworthia "Otago/Southland" changed with elevation and operative temperature (determined using physical copper models). In a laboratory study, we investigated whether thermoregulatory mode (heliothermy or thigmothermy) alters the effect of body size on heating and cooling rates. This gecko followed Bergmann's rule, thereby showing the opposite of the dominant pattern in diurnal lizards. Size at maturity, maximum size of adults and size at birth were larger at higher elevations and at lower operative temperatures. Using physical models, we found that large body size can confer thermal benefits for nocturnal lizards that remain within diurnal retreats. Bergmann's rule should not be dismissed for all lizards. Our results clearly support Bergmann's rule for at least one thigmothermic species, for which large body size may provide thermal benefits. Future studies on Bergmann's rule in lizards should consider thermoregulatory mode. We advocate that this ecogeographic rule be examined in relation to operative temperature measured at field sites. Finally, we predict that climate warming may weaken the relationship between body size and elevation in this gecko. PMID:25663371

  3. Artificial light and nocturnal activity in gammarids

    Elizabeth K. Perkin

    2014-03-01

    Full Text Available Artificial light is gaining attention as a potential stressor to aquatic ecosystems. Artificial lights located near streams increase light levels experienced by stream invertebrates and we hypothesized light would depress night drift rates. We also hypothesized that the effect of light on drift rates would decrease over time as the invertebrates acclimated to the new light level over the course of one month’s exposure. These hypotheses were tested by placing Gammarus spp. in eight, 75 m × 1 m artificial flumes. One flume was exposed to strong (416 lx artificial light at night. This strong light created a gradient between 4.19 and 0.04 lx over the neighboring six artificial flumes, while a control flume was completely covered with black plastic at night. Night-time light measurements taken in the Berlin area confirm that half the flumes were at light levels experienced by urban aquatic invertebrates. Surprisingly, no light treatment affected gammarid drift rates. In contrast, physical activity measurements of in situ individually caged G. roeseli showed they increased short-term activity levels in nights of complete darkness and decreased activity levels in brightly lit flumes. Both nocturnal and diurnal drift increased, and day drift rates were unexpectadly higher than nocturnal drift.

  4. Cold air drainage and modeled nocturnal leaf water potential in complex forested terrain.

    Hubbart, Jason A; Kavanagh, Kathleen L; Pangle, Robert; Link, Tim; Schotzko, Alisa

    2007-04-01

    Spatial variation in microclimate caused by air temperature inversions plays an important role in determining the timing and rate of many physical and biophysical processes. Such phenomena are of particular interest in mountainous regions where complex physiographic terrain can greatly complicate these processes. Recent work has demonstrated that, in some plants, stomata do not close completely at night, resulting in nocturnal transpiration. The following work was undertaken to develop a better understanding of nocturnal cold air drainage and its subsequent impact on the reliability of predawn leaf water potential (Psi(pd)) as a surrogate for soil water potential (Psi(s)). Eight temperature data loggers were installed on a transect spanning a vertical distance of 155 m along a north facing slope in the Mica Creek Experimental Watershed (MCEW) in northern Idaho during July and August 2004. Results indicated strong nocturnal temperature inversions occurring from the low- to upper-mid-slope, typically spanning the lower 88 m of the vertical distance. Based on mean temperatures for both months, inversions resulted in lapse rates of 29.0, 27.0 and 25.0 degrees C km(-1) at 0000, 0400 and 2000 h, respectively. At this scale (i.e., cold air drainage, modeled Psi(pd) became consistently more negative (up to -0.3 MPa) at higher elevations during the night based on mean temperatures. Nocturnal inversions on the lower- and mid-slopes resulted in leaf water potentials that were at least 30 and 50% more negative over the lower 88 m of the inversion layer, based on mean and maximum temperatures, respectively. However, on a cloudy night, with low D, the maximum decrease in Psi(pd) was -0.04 MPa. Our results indicate that, given persistent cold air drainage and nighttime stomatal opening, serious errors will result if Psi(s) is estimated from Psi(pd). PMID:17242004

  5. Melatonina y deficiencia de hormona de crecimiento: contribucin a la evaluacin de los desrdenes neuroendocrinos Melatonin and growth hormone deficiency: a contribution to the evaluation of neuroendocrine disorders

    G Fideleff

    2011-10-01

    . The relationship between melatonin and different pituitary hormones and sex steroids has been studied; however, the relationship between growth hormone (GH and melatonin remains unclear. Considering that melatonin is an essential component of the so-called "biological clock", related to circadian rhythm, day-night cycle, and sleep-dependent hormonal alterations, and knowing that physiological GH secretion occurs predominantly at night, we decided to evaluate nocturnal melatonin secretion in a group of GH-deficient children and adults on and off replacement therapy. Patients and Methods: We studied 44 patients with GH deficiency (GHD, duly confirmed by pharmacological tests, divided into 4 groups: Group a (Ga : untreated GHD children; Group b (Gb: GHD children on GH replacement therapy (0.16 mg/Kg/week, stable dose for at least 6 months; Group c (Gc: untreated GHD adults and Group d (Gd: GHD adults on GH replacement therapy (0.1- 0.8 mg/day, to maintain IGF1 between 0 and +2 SDS, stable dose for at least 6 months. All associated hormonal deficits were adequately replaced. Melatonin production was evaluated by measuring the excretion of its major urinary metabolite: 6-Sulphatoxymelatonin (6-SM. Urinary 6-SM was measured (radioimmunoassay, Stockgrand Ltd, Guildford, UK in nocturnal samples (6PM to 8AM in all patients. Results: Nocturnal 6-SM levels expressed as μg/unit of time were (mean SEM for the pediatric group: Ga = 6.50 ( 5.10 and Gb = 8.21 ( 5.31 (Mann Whitney test, p = 0.82. For adults: Gc = 2.99 ( 1.17 and Gd = 6.60 ( 2.00 (Mann Whitney test, p = 0.35. Discussion and Conclusions: It is difficult to characterize the relationship between melatonin and GH in healthy individuals; however, the administration of intravenous melatonin stimulates GH secretion in normal adults. In some hypothalamic-pituitary alterations, changes in the secretory pattern of melatonin have been reported, but possible variations in GHD patients have not been thoroughly characterized yet

  6. Protective Role of Melatonin in Neonatal Diseases

    Eloisa Gitto

    2013-01-01

    Full Text Available Oxidative stress contributes to the severity of several newborn conditions to the extent that Saugstad coined the phrase “oxygen radical diseases of neonatology.” In order to counteract free radicals damage many strategies to augment antioxidant status in ill-term and preterm infants have been proposed and several medications have been experimented with mixed results. Several studies have tested the efficacy of melatonin to counteract oxidative damage in diseases of newborns such as chronic lung disease, perinatal brain injury, necrotizing enterocolitis, and retinopathy of prematurity, giving promising results. The peculiar perinatal susceptibility to oxidative stress indicates that prophylactic use of antioxidants as melatonin could help to prevent or at least reduce oxidative stress related diseases in newborns. However, more studies are needed to confirm these beneficial effects.

  7. Transient species and its properties of melatonin

    ZHU; Hongping; ZHANG; Zhaoxia; ZHAO; Hongwei; WANG; Wenfeng; YAO; Side

    2006-01-01

    The photo-physical and photo-chemical properties of melatonin (ML) were studied by266 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radical cation of ML(ML·+) and hydrated electrons (e-aq), while excited triplet state 3ML* is also formed during photolysis.The oxidation via one electron transfer from ML to SO4·-and the triplet state of riboflavin (3RF*) has been also investigated and the rate constants for the process have been determined to be 8.0×109and 1.4×109 L·mol-1·s-1 respectively. The radical cation of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS·+) scavenging capacities of melatonin and other antioxidants are compared in this paper.

  8. Fundamental Issues Related to the Origin of Melatonin and Melatonin Isomers during Evolution: Relation to Their Biological Functions

    Dun-Xian Tan

    2014-09-01

    Full Text Available Melatonin and melatonin isomers exist and/or coexist in living organisms including yeasts, bacteria and plants. The levels of melatonin isomers are significantly higher than that of melatonin in some plants and in several fermented products such as in wine and bread. Currently, there are no reports documenting the presence of melatonin isomers in vertebrates. From an evolutionary point of view, it is unlikely that melatonin isomers do not exist in vertebrates. On the other hand, large quantities of the microbial flora exist in the gut of the vertebrates. These microorganisms frequently exchange materials with the host. Melatonin isomers, which are produced by these organisms inevitably enter the host’s system. The origins of melatonin and its isomers can be traced back to photosynthetic bacteria and other primitive unicellular organisms. Since some of these bacteria are believed to be the precursors of mitochondria and chloroplasts these cellular organelles may be the primary sites of melatonin production in animals or in plants, respectively. Phylogenic analysis based on its rate-limiting synthetic enzyme, serotonin N-acetyltransferase (SNAT, indicates its multiple origins during evolution. Therefore, it is likely that melatonin and its isomer are also present in the domain of archaea, which perhaps require these molecules to protect them against hostile environments including extremely high or low temperature. Evidence indicates that the initial and primary function of melatonin and its isomers was to serve as the first-line of defence against oxidative stress and all other functions were acquired during evolution either by the process of adoption or by the extension of its antioxidative capacity.

  9. Effects and mechanisms of melatonin on neural differentiation of induced pluripotent stem cells.

    Shu, Tao; Wu, Tao; Pang, Mao; Liu, Chang; Wang, Xuan; Wang, Juan; Liu, Bin; Rong, Limin

    2016-06-01

    Melatonin, a lipophilic molecule mainly synthesized in the pineal gland, has properties of antioxidation, anti-inflammation, and antiapoptosis to improve neuroprotective functions. Here, we investigate effects and mechanisms of melatonin on neural differentiation of induced pluripotent stem cells (iPSCs). iPSCs were induced into neural stem cells (NSCs), then further differentiated into neurons in medium with or without melatonin, melatonin receptor antagonist (Luzindole) or Phosphatidylinositide 3 kinase (PI3K) inhibitor (LY294002). Melatonin significantly promoted the number of neurospheres and cell viability. In addition, Melatonin markedly up-regulated gene and protein expression of Nestin and MAP2. However, Luzindole or LY294002 attenuated these increase. The expression of pAKT/AKT were increased by Melatonin, while Luzindole or LY294002 declined these melatonin-induced increase. These results suggest that melatonin significantly increased neural differentiation of iPSCs via activating PI3K/AKT signaling pathway through melatonin receptor. PMID:27130826

  10. Studies on circadian rhythm disturbances and melatonin in delirium

    A.-M. de Jonghe

    2014-01-01

    The circadian sleep/wake rhythm disturbances that are seen in delirium and the role of melatonin supplementation provide a new angle in delirium research. More research is needed to determine the role of melatonin in the pathophysiological mechanisms of delirium and to determine whether the restorat

  11. A systematic review of peri-operative melatonin

    Andersen, L P H; Werner, M U; Rosenberg, J;

    2014-01-01

    We systematically reviewed randomised controlled trials of peri-operative melatonin. We included 24 studies of 1794 participants that reported eight peri-operative outcomes: anxiety; analgesia; sleep quality; oxidative stress; emergence behaviour; anaesthetic requirements; steal induction; and......%, respectively. Qualitative reviews suggested the melatonin improved sleep quality and emergence behaviour, and might be capable of reducing oxidative stress and anaesthetic requirements....

  12. MELATONIN AND IMMUNOMODULATION IN AGED AND IMMUNODEFICIENT MICE

    周爱民; 袁育康; 范桂香

    2003-01-01

    Objective To investigate melatonin-related mechanisms of action on immunoregulation in aged and immunodeficient mice. Methods T lymPhocytes subunit CD4+,CD8+ and CD4+/CD8+ ratio were measured by Flow Cytometer in normal, aged and Cyclophosphamide injected mice which treated with melatonin, and compared with the results of T lymphocytes subunit in the group without melatonin as control group. Results The percentage of CD4+, CD8+ T cells in the normal mice which treated with melatonin was significantly higher than that in control group (P<0.01), CD4+/CD8+ ratio was higher but had no significant difference. In the cyclophosphamide injected group which melatonin treated, the percentage of CD4+ T cells and CD4+/CD8+ ratio were higher than those in control, The difference was significant (P<0.01), while CD8+ was lower (P<0.01). In aged melatonin treated mice group, the percentage of CD4+, CD8+ T cells and CD4+/CD8+ ratio were significantly higher than those in control (P<0.01). Conclusion Melatonin could adjust the quantity and the ratio of CD4+, CD8+ T cells in aged and immunodeficient mice. it implied that melatonin could mediate helper and suppression T lymphocytes to reinforce their immunodefence.

  13. Melatonin improves spatial navigation memory in male diabetic rats

    Farrin Babaei-Balderlou

    2012-09-01

    Full Text Available The aim of the present study was to evaluate the effect of melatonin as an antioxidant on spatial navigation memory in male diabetic rats. Thirty-two male white Wistar rats weighing 200 ± 20 g were divided into four groups, randomly: control, melatonin, diabetic and melatonin-treated diabetic. Experimental diabetes was induced by intraperitoneal injection of 50 mg kg-1 streptozotocin. Melatonin was injected (10 mg kg-1 day-1, ip for 2 weeks after 21 days of diabetes induction. At the end of administration period, the spatial navigation memory of rats was evaluated by cross-arm maze. In this study lipid peroxidation levels, glutathione-peroxidase and catalase activities were measured in hippocampus. Diabetes caused to significant decrease in alternation percent in the cross-arm maze, as a spatial memory index, compared to the control group (p < 0.05, whereas administration of melatonin prevented the spatial memory deficit in diabetic rats. Also melatonin injection significantly increased the spatial memory in intact animals compared to the control group (p < 0.05. Assessment of hippocampus homogenates indicated an increase in lipid peroxidation levels and a decrease in GSH-Px and CAT activities in the diabetic group compared to the control animals, while melatonin administration ameliorated these indices in diabetic rats. In conclusion, diabetes induction leads to debilitation of spatial navigation memory in rats, and the melatonin treatment improves the memory presumably through the reduction of oxidative stress in hippocampus of diabetic rats.

  14. High levels of melatonin generated during the brewing process.

    Garcia-Moreno, H; Calvo, J R; Maldonado, M D

    2013-08-01

    Beer is a beverage consumed worldwide. It is produced from cereals (barley or wheat) and contains a wide array of bioactive phytochemicals and nutraceutical compounds. Specifically, high melatonin concentrations have been found in beer. Beers with high alcohol content are those that present the greatest concentrations of melatonin and vice versa. In this study, gel filtration chromatography and ELISA were combined for melatonin determination. We brewed beer to determine, for the first time, the beer production steps in which melatonin appears. We conclude that the barley, which is malted and ground in the early process, and the yeast, during the second fermentation, are the largest contributors to the enrichment of the beer with melatonin. PMID:23607887

  15. Beneficial effects of melatonin in experimental models of Alzheimer disease

    Yong CHENG; Zheng FENG; Qing-zhu ZHANG; Jun-tian ZHANG

    2006-01-01

    Alzheimer's disease (AD), a progressive degenerative disorder, is characterized by the presence of amyloid deposits, neurofibrillary tangles and neuron loss.Emerging evidence indicates that antioxidants could be useful either for the prevention or treatment of AD. It has been shown that melatonin is a potent antioxidant and free radical scavenger. Additionally, melatonin stimulates several antioxidative enzymes and improves mitochondrial energy metabolism. These findings led us to study amyloid precursor protein transgenic mice, ovariectomized rats, and pheochromocytoma and astroglioma cell lines, to observe whether melatonin had any effect on Alzheimer's symptoms or pathological changes. We found that melatonin had many beneficial effects in experimental models of AD, including improvement of cognitive function, anti-oxidative injury, anti-apoptosis, inhibition of β-amyloid (Aβ) deposition and Aβ fiber formation. Several groups have shown that melatonin has an inhibitory effect on tau protein hyperphosphorylation.These actions may potentially slow down or stop the progression of dementia.

  16. Melatonin Signaling Controls the Daily Rhythm in Blood Glucose Levels Independent of Peripheral Clocks

    Owino, Sharon; Contreras-Alcantara, Susana; Baba, Kenkichi; Tosini, Gianluca

    2016-01-01

    Melatonin is rhythmically secreted by both the pineal gland and retina in a circadian fashion, with its peak synthesis occurring during the night. Once synthesized, melatonin exerts its effects by binding to two specific G-protein coupled receptors–melatonin receptor type 1(MT1) and melatonin receptor type 2(MT2). Recent studies suggest the involvement of MT1 and MT2 in the regulation of glucose homeostasis; however the ability of melatonin signaling to impart timing cues on glucose metabolis...

  17. The role of melatonin in mood disorders

    De Berardis D

    2015-11-01

    Full Text Available Domenico De Berardis,1–3 Laura Orsolini,3–5 Nicola Serroni,1 Gabriella Girinelli,1–3 Felice Iasevoli,3–6 Carmine Tomasetti,3–6 Monica Mazza,3–7 Alessandro Valchera,3–8 Michele Fornaro,9 Giampaolo Perna,10–12 Monica Piersanti,13Marco Di Nicola,14 Marilde Cavuto,15 Giovanni Martinotti,2 Massimo Di Giannantonio21NHS, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, Hospital "G Mazzini", Teramo, Italy; 2Department of Neuroscience, Imaging and Clinical Science, Chair of Psychiatry, University G d'Annunzio, Chieti, Italy; 3Polyedra, Teramo, Italy; 4United Hospitals, Academic Department of Experimental and Clinical Medicine, Polytechnic University of Marche, Ancona, Italy; 5School of Life and Medical Sciences, University of Hertfordshire, Hatfield, Hertfordshire, UK; 6Laboratory of Molecular Psychiatry and Psychopharmacotherapeutics, Section of Psychiatry, Department of Neuroscience, University School of Medicine Federico II, Naples, Italy; 7Department of Health Sciences, University of L'Aquila, L'Aquila, Italy; 8Villa S Giuseppe Hospital, Hermanas Hospitalarias, Ascoli Piceno, Italy; 9Department of Scienze della Formazione, University of Catania, Catania, Italy; 10Hermanas Hospitalarias, FoRiPsi, Department of Clinical Neurosciences, Villa San Benedetto Menni, Albese con Cassano, Como, Italy; 11Department of Psychiatry and Neuropsychology, University of Maastricht, Maastricht, the Netherlands; 12Department of Psychiatry and Behavioral Sciences, Leonard Miller School of Medicine, University of Miami, Miami, FL, USA; 13Hospital Pharmacy, Hospital G Mazzini, ASL 4 Teramo, Italy; 14Institute of Psychiatry and Psychology, Catholic University of Sacred Heart, Rome, Italy; 15IASM, L'Aquila, ItalyAbstract: Melatonin (N-acetyl-5-methoxytryptamine has been discovered as a hormone secreted by the pineal gland, even though it is also synthetized in various other organs, tissues, and cells. The circadian rhythm of

  18. Melatonin and its analogs in insomnia and depression.

    Cardinali, Daniel P; Srinivasan, Venkataramanujan; Brzezinski, Amnon; Brown, Gregory M

    2012-05-01

    Benzodiazepine sedative-hypnotic drugs are widely used for the treatment of insomnia. Nevertheless, their adverse effects, such as next-day hangover, dependence and impairment of memory, make them unsuitable for long-term treatment. Melatonin has been used for improving sleep in patients with insomnia mainly because it does not cause hangover or show any addictive potential. However, there is a lack of consistency on its therapeutic value (partly because of its short half-life and the small quantities of melatonin employed). Thus, attention has been focused either on the development of more potent melatonin analogs with prolonged effects or on the design of slow release melatonin preparations. The MT(1) and MT(2) melatonergic receptor ramelteon was effective in increasing total sleep time and sleep efficiency, as well as in reducing sleep latency, in insomnia patients. The melatonergic antidepressant agomelatine, displaying potent MT(1) and MT(2) melatonergic agonism and relatively weak serotonin 5HT(2C) receptor antagonism, was found effective in the treatment of depressed patients. However, long-term safety studies are lacking for both melatonin agonists, particularly considering the pharmacological activity of their metabolites. In view of the higher binding affinities, longest half-life and relative higher potencies of the different melatonin agonists, studies using 2 or 3mg/day of melatonin are probably unsuitable to give appropriate comparison of the effects of the natural compound. Hence, clinical trials employing melatonin doses in the range of 50-100mg/day are warranted before the relative merits of the melatonin analogs versus melatonin can be settled. PMID:21951153

  19. Radioprotective effects of melatonin on radiation-induced cataract

    One of the mechanisms proposed to explain lens opacification is the oxidation of crystallins, either by radiation or reactive oxygen species (ROS). It has been shown that melatonin has both an anti-peroxidative effect on several tissues and a scavenger effect on ROS. The purpose of this study was to determine the antioxidant role of melatonin (5 mg/kg/day) against radiation-induced cataract in the lens after total-cranium irradiation of rats with a single dose of 5 Gy. Sprague-Dawley rats were divided into four groups. Control group received neither melatonin nor irradiation. Irradiated rats (IR) and melatonin+irradiated rats (IR+Mel) groups were exposed to total cranium irradiation of 5 Gy in a single dose by using a cobalt-60 teletherapy unit. IR+Mel and melatonin (Mel) groups were administered 5 mg/kg melatonin daily by intraperitoneal injections during ten days. Chylack's cataract classification was used in this study. At the end of the 10th day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes i.e. the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and lipid peroxidation level (malondialdehyde (MDA)). Irradiation significantly increased the MDA level, as an end product of lipid peroxidation, and also significantly decreased SOD and GSH-Px activity, emphasizing the generation of increased oxidative stress. Rats injected with melatonin only did not cause cataract formation. Melatonin supplementation with irradiation significantly increased the activity of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose enhanced cataract formation, and melatonin supplementation protected the lenses from radiation-induced cataract formation. Our results suggest that supplementing cancer patients with adjuvant therapy of melatonin may reduce patients suffering from toxic therapeutic regimens such as chemotherapy and/or radiotherapy and may provide

  20. Behavioral alarm treatment for nocturnal enuresis

    Rodrigo F. Pereira

    2010-06-01

    Full Text Available PURPOSES: To investigate the efficacy of alarm treatment in a sample of Brazilian children and adolescents with nocturnal enuresis and relate treatment success to age and type of clinical support. MATERIALS AND METHODS: During 32 weeks, 84 children and adolescents received alarm treatment together with weekly psychological support sessions for individual families or groups of 5 to 10 families. RESULTS: 71% of the participants achieved success, defined as 14 consecutive dry nights. The result was similar for children and adolescents and for individual or group support. The time until success was shorter for participants missing fewer support sessions. CONCLUSIONS: Alarm treatment was effective for the present sample, regardless of age or type of support. Missing a higher number of support sessions, which may reflect low motivation for treatment, increased the risk of failure.

  1. Clinical correlation between hypercalciuria and nocturnal enuresis

    Ehsan Valavi

    2011-01-01

    Full Text Available Hypercalciuria may present with dysuria, urinary incontinence and nocturnal enuresis (NE. To determine the frequency of hypercalciuria in NE patients and normally continent children, we studied 122 consecutive pre- school children with NE referred to our nephrology clinic during two years, from September 2007 to August 2009. We measured the 24- hour urinary calcium. Furthermore, we compared the response to nasal desmopressin in hypercalciuric and normocalciuric patients. Hypercalciuria was found in 26 (21.3 % of the NE patients as compared with five (4.5% of 110 continent children [(P 0.05. The response to desmopressin above 90% occurred within one month of therapy without a significant change in the levels of hypercalciuria. We conclude that these results suggest that hypercalciuria has a significant association with NE and does not interfere with the desmopressin therapy.

  2. Ambient Light Intensity, Actigraphy, Sleep and Respiration, Circadian Temperature and Melatonin Rhythms and Daytime Performance of Crew Members During Space Flight on STS-90 and STS-95 Missions

    Czeisler, Charles A.; Dijk, D.-J.; Neri, D. F.; Hughes, R. J.; Ronda, J. M.; Wyatt, J. K.; West, J. B.; Prisk, G. K.; Elliott, A. R.; Young, L. R.

    1999-01-01

    Sleep disruption and associated waking sleepiness and fatigue are common during space flight. A survey of 58 crew members from nine space shuttle missions revealed that most suffered from sleep disruption, and reportedly slept an average of only 6.1 hours per day of flight as compared to an average of 7.9 hours per day on the ground. Nineteen percent of crewmembers on single shift missions and 50 percent of the crewmembers in dual shift operations reported sleeping pill usage (benzodiazepines) during their missions. Benzodiazepines are effective as hypnotics, however, not without adverse side effects including carryover sedation and performance impairment, anterograde amnesia, and alterations in sleep EEG. Our preliminary ground-based data suggest that pre-sleep administration of 0.3 mg of the pineal hormone melatonin may have the acute hypnotic properties needed for treating the sleep disruption of space flight without producing the adverse side effects associated with benzodiazepines. We hypothesize that pre-sleep administration of melatonin will result in decreased sleep latency, reduced nocturnal sleep disruption, improved sleep efficiency, and enhanced next-day alertness and cognitive performance both in ground-based simulations and during the space shuttle missions. Specifically, we have carried out experiments in which: (1) ambient light intensity aboard the space shuttle is assessed during flight; (2) the impact of space flight on sleep (assessed polysomnographically and actigraphically), respiration during sleep, circadian temperature and melatonin rhythms, waking neurobehavioral alertness and performance is assessed in crew members of the Neurolab and STS-95 missions; (3) the effectiveness of melatonin as a hypnotic is assessed independently of its effects on the phase of the endogenous circadian pacemaker in ground-based studies, using a powerful experimental model of the dyssomnia of space flight; (4) the effectiveness of melatonin as a hypnotic is

  3. Melatonin deacetylation: retinal vertebrate class distribution and Xenopus laevis tissue distribution.

    Grace, M S; Cahill, G M; Besharse, J C

    1991-09-13

    Deacetylation is a rapid clearance mechanism for ocular melatonin. We have studied the distribution of retinal melatonin deacetylase activity among vertebrate classes. Exogenous radiolabeled melatonin is metabolized by ocular tissue prepared from the amphibian Xenopus laevis, the reptile Anolis carolinensis, the teleost fish Carassius auratus, and the bird Gallus domesticus. In contrast, we were unable to detect ocular melatonin breakdown in rat or pig. In each species exhibiting ocular melatonin breakdown, melatonin is first deacetylated to 5-methoxytryptamine, which is deaminated, producing 5-methoxyindoleacetic acid and 5-methoxytryptophol. Deacetylation of melatonin is inhibited by eserine (physostigmine), causing a reduction in the levels of all 3 metabolites. Deamination of 5-methoxytryptamine is inhibited by the monoamine oxidase inhibitor pargyline, such that 5-methoxyindoleacetic acid and 5-methoxytryptophol levels are decreased while levels of 5-methoxytryptamine are increased. Incubation with the deacetylase inhibitor eserine increases endogenous melatonin levels in Xenopus and Carassius eyecups, indicating that endogenous melatonin is metabolized via the deacetylase. We also studied the tissue distribution of the deacetylase in Xenopus laevis. Melatonin deacetylation occurs in retina, retinal pigment epithelium, and skin, all of which are sites of melatonin action. These results indicate that among non-mammalian vertebrates, deacetylation is a common clearance mechanism for ocular melatonin, and may degrade melatonin at other sites of action as well. Melatonin deacetylation may help regulate local melatonin concentration, and generates other biologically active methoxyindoles. PMID:1782560

  4. Loss of response to melatonin treatment is associated with slow melatonin metabolism

    Braam, W.J.; Geijlswijk, I.M. van; Keijzer, H.; Smits, M.G.; Didden, H.C.M.; Curfs, L.M.G

    2010-01-01

    Background In some of our patients with intellectual disability (ID) and sleep problems, the initial good response to melatonin disappeared within a few weeks after starting treatment, while the good response returned only after considerable dose reduction. The cause for this loss of response to mel

  5. The Australian Bogong Moth Agrotis infusa: A Long-Distance Nocturnal Navigator.

    Warrant, Eric; Frost, Barrie; Green, Ken; Mouritsen, Henrik; Dreyer, David; Adden, Andrea; Brauburger, Kristina; Heinze, Stanley

    2016-01-01

    The nocturnal Bogong moth (Agrotis infusa) is an iconic and well-known Australian insect that is also a remarkable nocturnal navigator. Like the Monarch butterflies of North America, Bogong moths make a yearly migration over enormous distances, from southern Queensland, western and northwestern New South Wales (NSW) and western Victoria, to the alpine regions of NSW and Victoria. After emerging from their pupae in early spring, adult Bogong moths embark on a long nocturnal journey towards the Australian Alps, a journey that can take many days or even weeks and cover over 1000 km. Once in the Alps (from the end of September), Bogong moths seek out the shelter of selected and isolated high ridge-top caves and rock crevices (typically at elevations above 1800 m). In hundreds of thousands, moths line the interior walls of these cool alpine caves where they "hibernate" over the summer months (referred to as "estivation"). Towards the end of the summer (February and March), the same individuals that arrived months earlier leave the caves and begin their long return trip to their breeding grounds. Once there, moths mate, lay eggs and die. The moths that hatch in the following spring then repeat the migratory cycle afresh. Despite having had no previous experience of the migratory route, these moths find their way to the Alps and locate their estivation caves that are dotted along the high alpine ridges of southeastern Australia. How naïve moths manage this remarkable migratory feat still remains a mystery, although there are many potential sensory cues along the migratory route that moths might rely on during their journey, including visual, olfactory, mechanical and magnetic cues. Here we review our current knowledge of the Bogong moth, including its natural history, its ecology, its cultural importance to the Australian Aborigines and what we understand about the sensory basis of its long-distance nocturnal migration. From this analysis it becomes clear that the Bogong

  6. The Australian Bogong moth Agrotis infusa: A long-distance nocturnal navigator

    Eric eWarrant

    2016-04-01

    Full Text Available The nocturnal Bogong moth (Agrotis infusa is an iconic and well-known Australian insect that is also a remarkable nocturnal navigator. Like the Monarch butterflies of North America, Bogong moths make a yearly migration over enormous distances, from southern Queensland, western and northwestern New South Wales (NSW and western Victoria, to the alpine regions of NSW and Victoria. After emerging from their pupae in early spring, adult Bogong moths embark on a long nocturnal journey towards the Australian Alps, a journey that can take many days or even weeks and cover over 1000 km. Once in the Alps (from the end of September, Bogong moths seek out the shelter of selected and isolated high ridge-top caves and rock crevices (typically at elevations above 1800 m. In hundreds of thousands, moths line the interior walls of these cool alpine caves where they hibernate over the summer months (referred to as aestivation. Towards the end of the summer (February and March, the same individuals that arrived months earlier leave the caves and begin their long return trip to their breeding grounds. Once there, moths mate, lay eggs and die. The moths that hatch in the following spring then repeat the migratory cycle afresh. Despite having had no previous experience of the migratory route, these moths find their way to the Alps and locate their aestivation caves that are dotted along the high alpine ridges of southeastern Australia. How naïve moths manage this remarkable migratory feat still remains a mystery, although there are many potential sensory cues along the migratory route that moths might rely on during their journey, including visual, olfactory, mechanical and magnetic cues. Here we review our current knowledge of the Bogong moth, including its natural history, its ecology, its cultural importance to the Australian Aborigines and what we understand about the sensory basis of its long-distance nocturnal migration. From this analysis it becomes clear

  7. The Australian Bogong Moth Agrotis infusa: A Long-Distance Nocturnal Navigator

    Warrant, Eric; Frost, Barrie; Green, Ken; Mouritsen, Henrik; Dreyer, David; Adden, Andrea; Brauburger, Kristina; Heinze, Stanley

    2016-01-01

    The nocturnal Bogong moth (Agrotis infusa) is an iconic and well-known Australian insect that is also a remarkable nocturnal navigator. Like the Monarch butterflies of North America, Bogong moths make a yearly migration over enormous distances, from southern Queensland, western and northwestern New South Wales (NSW) and western Victoria, to the alpine regions of NSW and Victoria. After emerging from their pupae in early spring, adult Bogong moths embark on a long nocturnal journey towards the Australian Alps, a journey that can take many days or even weeks and cover over 1000 km. Once in the Alps (from the end of September), Bogong moths seek out the shelter of selected and isolated high ridge-top caves and rock crevices (typically at elevations above 1800 m). In hundreds of thousands, moths line the interior walls of these cool alpine caves where they “hibernate” over the summer months (referred to as “estivation”). Towards the end of the summer (February and March), the same individuals that arrived months earlier leave the caves and begin their long return trip to their breeding grounds. Once there, moths mate, lay eggs and die. The moths that hatch in the following spring then repeat the migratory cycle afresh. Despite having had no previous experience of the migratory route, these moths find their way to the Alps and locate their estivation caves that are dotted along the high alpine ridges of southeastern Australia. How naïve moths manage this remarkable migratory feat still remains a mystery, although there are many potential sensory cues along the migratory route that moths might rely on during their journey, including visual, olfactory, mechanical and magnetic cues. Here we review our current knowledge of the Bogong moth, including its natural history, its ecology, its cultural importance to the Australian Aborigines and what we understand about the sensory basis of its long-distance nocturnal migration. From this analysis it becomes clear that

  8. Effectiveness of Psychological and Pharmacological Treatments for Nocturnal Enuresis.

    Houts, Arthur C.; And Others

    1994-01-01

    Assesses overall effectiveness of psychological and pharmacological treatments, relative effectiveness of specific treatments, and moderators of treatment effectiveness for nocturnal enuretic children via quantitative integration of research. Findings confirm that more children benefit from psychological than from pharmacological interventions and…

  9. Concentração plasmática de melatonina em novilhas bubalinas (Bubalus bubalis ao longo do ano Plasma melatonin in bufallo heifers (Bubalus bubalis during a year

    P.S.R. Mattos

    2000-10-01

    Full Text Available Coletaram-se nove amostras de sangue ao longo do dia, mês-a-mês durante um ano, de seis novilhas bubalinas da raça Mediterrâneo, para determinação da melatonina plasmática dos animais mantidos na latitude 22° Sul. A concentração plasmática de melatonina se elevou lentamente até atingir o pico entre 21 e 23 horas, permanecendo elevada até as 3-5 horas. A seguir, a concentração diminuiu para valores baixos antes do nascer do sol. A duração da elevação noturna de melatonina plasmática não acompanhou a duração do período noturno ao longo do ano e a diminuição da concentração diurna de melatonina plasmática ocorreu na época de maior atividade reprodutiva estimada do rebanho.Nine blood samples were taken to determine plasma melatonin in a 24h-period/month for a year. The six buffalo heifers used were kept at latitude 22° South. Plasma melatonin rose slowly, peaking at night (between 9 and 11pm and maintained until 3 to 5am. Melatonin concentration decreased day-time to lower levels until sunrise. Nocturnal higher plasmatic melatonin did not vary with night length over the year. Diurnal melatonin concentrations were lower when estimated reproductive rate was the highest for the herd.

  10. A radiobiological review on melatonin. A novel radioprotector

    Complete text of publication follows. For the sake of improvement in radiation therapy, radiobiology plays a crucial role through explaining observed phenomena, and suggesting improvements to existing therapies. Due to the damaging effects of ionizing radiation, radiobiologists have long been interested in identifying novel, nontoxic, effective, and convenient compounds to protect humans against radiation induced normal tissue injuries. Melatonin (N-acetyl-5-methoxytryptamine), the chief secretory product of the pineal gland in the brain, has been documented to ameliorate the oxidative injuries due to ionizing radiation. This article reviews different features that make melatonin a potentially useful radioprotector. Moreover, based on radiobiological models we hypothesize that melatonin may postpone the saturation of repair enzymes which leads to repairing more induced damage by repair system and more importantly allows the use of higher doses of radiation during radiotherapy to get a better therapeutic ratio. The implications of the accumulated observations suggest by virtue of melatonin's radioprotective and anticancer effects; it is time to use it as a radioprotector both for radiation workers and patients suffering from cancer either alone for cancer inhibition or in combination with traditional radiotherapy for getting a favorable efficacy/toxicity ratio during the treatment. Although compelling evidence suggests that melatonin may be effective for a variety of disorders, the optimum dose of melatonin for human radioprotection is yet to be determined by further research. We propose that, in the future melatonin improve therapeutic ratio in radiation oncology.