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![Age variations of melatonin levels. The hormone secretion increases in early childhood. In adolescent there is a decrease of the hormone concentration. The levels continued to decline gradually during middle age. In old population the levels of melatonin in serum are very low. (Modified from [88]).](profile/Theodoros-Grivas-2/publication/6414433/figure/fig5/AS:280125976399909@1443798645964/Age-variations-of-melatonin-levels-The-hormone-secretion-increases-in-early-childhood.png)
Age variations of melatonin levels. The hormone secretion increases in early childhood. In adolescent there is a decrease of the hormone concentration. The levels continued to decline gradually during middle age. In old population the levels of melatonin in serum are very low. (Modified from [88]).
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![Figure 1: Biosynthesis of melatonin. Modified from [48].](profile/Theodoros-Grivas-2/publication/6414433/figure/fig2/AS:279902633906187@1443745396248/Biosynthesis-of-melatonin-Modified-from-48_Q320.jpg)
![Figure 2: Melatonin molecule. (Modified from [86]).](profile/Theodoros-Grivas-2/publication/6414433/figure/fig1/AS:279840117805083@1443730491983/Melatonin-molecule-Modified-from-86_Q320.jpg)
Melatonin "the light of night" is secreted from the pineal gland principally at night. The hormone is involved in sleep regulation, as well as in a number of other cyclical bodily activities and circadian rhythm in humans. Melatonin is exclusively involved in signalling the 'time of day' and 'time of year' (hence considered to help both clock and c...
Citations
... It thus creates a state necessary for insulin sensitivity during the day [39]. Peak plasma melatonin at late night (02:00-04:00 h) ranges from 100 to 200 pg/ mL [40]; melatonin levels range from 10 to 30 pg/mL during the day [41]. Illumination from 200 to 600 lux inhibits melatonin secretion [42]. ...
Introduction: Artificial lighting at night (ALAN) leads to pervasive light pollution, affecting ecosystems and human health globally. Satellite assessments reveal widespread nocturnal illumination worldwide and research indicates adverse health effects. Environmental light pollution disrupts natural cycles, affecting the behavior and reproduction of various organisms. Aim/Method: In this narrative review we aimed to present research on the effects of ALAN on glucose metabolism and diabetes and hone on its recently reported association with gestational diabetes (GDM). Results: Conflicting data exist on the effects of melatonin’s administration vis-à-vis glycemia, with some studies suggesting beneficial outcomes for patients with type 2 diabetes mellitus and insomnia. Ambient light influences plasma glucose, with bright light increasing both fasting and postprandial glucose levels. Perinatal light exposure is linked to later-life health risks and prenatal exposure to ALAN is linked to fetal macrosomia. Analyzing European ALAN data in conjunction with epidemiological records for GDM reveals a notable probable association. Additionally, recent research from China (one case-control and two cohort studies) has shown that exposure to ALAN during pregnancy significantly increases the risk of GDM. Discussion/Conclusion: Despite progress, interdisciplinary research is needed to understand the impact of light pollution on health, especially regarding disrupted light-dark cycles and physiological functions relevant to conditions like GDM. At present, the simplest advice for all people and particularly for women who anticipate pregnancy, or for pregnant women, is to ensure a totally dark environment during sleep time.
... Melatonin, "the light of night", is secreted from the pineal gland principally at night. It is involved in sexual maturation in females [113]. Abnormally high or pharmacologic concentrations of melatonin in women are associated with altered ovarian function and anovulation. ...
Background/Objectives: This opinion paper provides a brief overview of the history of school scoliosis screening programs following the introduction. Methods: It outlines the international administrative policies of these programs, their impact on the frequency of surgical procedures, and the effects of discontinuing school-based scoliosis screenings. Results: The primary focus is on analyzing the role of “false positive” cases detected during the Adam’s bending test, which has contributed to the discontinuation of these programs in certain countries. This focused discussion is based on the impact of growth on the relationship between spinal and rib cage deformities. Furthermore, we propose the selection of the optimal age range for screening, considering the correlation between idiopathic scoliosis prevalence and geographical latitude. Conclusions: Lastly, we emphasize the importance of continuing scoliosis screening programs in schools.
... (13) Subsequently, its levels in the body increase with puberty and reach a plateau at puberty, followed by a gradual decline from the late twenties to the fifties. (14,15) 6 Graph 2 Fluctuations in melatonin levels with age. (14) Studies have shown that calcification of the pineal gland, which has the highest calcification rate among all organs and tissues of the human body, may also be responsible for reducing hormone secretion, (7) disease, (16) diet, (4) medication, (17) lifestyle (17) and exposure to bright light at night (18) may also have a significant impact on melatonin levels. ...
... (14,15) 6 Graph 2 Fluctuations in melatonin levels with age. (14) Studies have shown that calcification of the pineal gland, which has the highest calcification rate among all organs and tissues of the human body, may also be responsible for reducing hormone secretion, (7) disease, (16) diet, (4) medication, (17) lifestyle (17) and exposure to bright light at night (18) may also have a significant impact on melatonin levels. ...
... Acknowledgments: Not applicable. 14 ...
Introduction and aim of the study: Melatonin consumption is steadily increasing. In this literature review, the authors intended to introduce the latest scientific evidence on the influence of the sleep hormone not only on the quality of time spent in bed and jet lag, but also to consider possible other positive impacts. Its eventual effects on headaches, gastrointestinal complaints, or obesity were analyzed. Materials and methods: The authors searched the scientific literature utilizing search engines such as Science Direct, Cochrane, PubMed, Google Scholar, and UpToDate. The literature review focused on the association of melatonin with issues such as sleep, migraines, GERD, IBS, and jet lag. Results: Most of the articles reviewed in this study highlighted the positive effects of melatonin supplementation on sleep problems and jet lag. Furthermore, many studies report that it likewise has a beneficial impact on conditions not directly related to sleep, such as obesity, GERD, IBS, or migraine. Nevertheless, the articles emphasize the need for further research to establish treatment protocols and to select an optimal dose.
... Melatonin in the body is chiefly manufactured in three parts, including the pineal gland, the retina, and the digestive system, from the amino acid tryptophan. The maximum production of melatonin reaches 80-120 pg/mL between 2 and 4 in the morning, and its level decreases with the onset of daylight and reaches a concentration of (10-20 pg/mL) [28][29][30]. ...
Autism spectrum disorder (ASD) is a pervasive neurobehavioral condition characterized by disruption of behavioral and emotional patterns in individuals with this condition. Given that various environmental and genetic factors play a fundamental role in the pathophysiology of ASD, it can be said that ASD is a multifaceted disease. This study used scientific databases including Google Scholar, PubMed, Scopus, and Semantic Scholar. In this review, we aimed to select manuscripts based on our field and relevant to the topic of our article. Emerging studies have shown that many neural, anatomical, and chemical factors play a role in the development of ASD. In this regard, an increasing body of studies has pointed out the relationship between chemical factors, including hormones, which play an important role in ASD. These hormones include melatonin, serotonin, thyroid, oxytocin, vasopressin, insulin-like growth hormone (IGF-1), etc. For instance, IGF-1 levels are low in ASD individuals, or melatonin levels are reduced in ASD individuals. Therefore, with take into account these findings, in this review, we decided to check over the association of these hormones to ASD and have a concise overview of their potential as therapeutic solutions to reduce the effects of ASD.
... The Mel level in healthy humans varies depending on age, ranging from a few pM to~1400 pM. In addition to ageing, factors such as exposure to light decrease Mel secretion in the human body [5][6][7][8][9]. Mel is associated with sleep efficiency [10,11], mood regulation [12], retinal physiology [7,13], immunologic functions [14], seasonal affective disorder [15,16], sexual maturation, and reproduction [17,18] as well as being an effective antioxidant, anti-inflammatory, and neuroprotective agent [19,20]. ...
... CV can be used to study the electron-transfer kinetics and redox behavior at the electrode surface, whereas SWV allows the quantitative determination of electroactive analytes. Recently reported electrodes for Mel detection include glassy carbon electrode (GCE) modified with a nanopalladium polymer nanocomposite [17], a protein nanodot-gold nanoparticle (AuNP) polymer nanocomposite [43], AuNPs-multiwalled carbon nanotubes-3-n-propyl-(4-methylpyridinium) silsesquioxane chloride [44], and 2D-MoS 2 with cucurbit [8]uril [45]. Simpler system, such as carbon fiber electrode with fast scan cyclic voltammetry (FSCV) [46], the boron-doped diamond electrode (BDDE) with CV [47], BDDE with DPV and amperometry [48], and the carbon fiber electrode with DPV [49] have also been used for the detection of melatonin. ...
Voltammetric methods hold promise for the rapid and sensitive quantification ofmelatonin. This study reports the direct electrochemical quantification of melatonin using carbonnanotube (CNT) fiber cross-sections as microelectrodes. Six identical highly densified CNT fibercross-sections were employed to quantify melatonin in the range of 0.05–100 µM. The limit ofdetection and quantification were 10 and 35 nM, respectively, with a sensitivity of 0.1322 nA/µM.Interference studies with uric acid, hypoxanthine, and ascorbic acid demonstrate its performance.Real-world application was highlighted by measuring melatonin in food, pharmaceutical, andhuman urine samples
... Figure 5a-c show the alterations in L-tryptophan, serotonin and melatonin levels, respectively, in the blood serum of the rats during the entire experimental period of 6 days (post-acclimatization). At the end of the 3-day of consumption of the TSM-lean diet, serum levels of the above-mentioned molecules decreased significantly (p < 0.05) on day 10, although the natural trends of increase and decrease in serum serotonin and melatonin levels at different time of the day (when measured at 9 am in the morning and 3 am at midnight) remained unperturbed [54,55]. The wellness parameters also did not reflect abnormalities in physiological, neurological, and behavioural patterns indicating that the rats remained healthy and active throughout the study period. ...
An antioxidant-rich mushroom noodles (gluten-free) rich in L-tryptophan-serotonin-melatonin (TSM) was developed under minimal processing condition(s) without perturbing the natural antioxidant synergy. In vitro release kinetics studies in a standard dissolution apparatus confirmed substantial releases of the target biomolecules from the designer noodles in simulated salivary buffer (SSB), simulated gastric buffer (SGB), simulated intestinal buffer (SIB) and simulated rectal buffer (SRB). Post model fitting, it was evident that L-tryptophan and serotonin followed zero order release kinetics in SSB; while melatonin followed first order release kinetics in SSB and SRB, respectively. However, all the three biomolecules followed Korsmeyer’s- Peppas model kinetics in SGB and SIB; L-tryptophan and serotonin also followed the same release kinetics model in SRB. The in vivo bioavailabilities of these molecules were ascertained through feeding trials (of mushroom noodles) in male Sprague Dawley rats. An enhancement of ~ 95%, 20% and 44% of L-tryptophan, serotonin and melatonin, respectively, occurred in rat blood serum after 30 min of consumption of the designer noodles and decreased 50 min onwards. However, the natural trends of increase and decrease in serum serotonin and melatonin concentrations during different time of the day remained unaltered. These bioavailable molecules also increased insulin sensitivity in the liver and glucose uptake in the brain, as revealed by iHOMA2 prediction modelling. The findings of these investigations have the potential to inform this designer noodles to be a truly antioxidant-rich functional food product which holds promise in providing molecular nutrition, especially for populations with serotonin-melatonin deficiency.
... Once it enters the bloodstream, it can quickly spread throughout the body. Melatonin levels fluctuate throughout a 24-hour period, with the highest concentration expected between 2:00 and 4:00 am 10 , Low melatonin levels are associated with the peak hours of endogenous cortisol 11 . The average levels of melatonin in plasma range from 60 to 70 pg/ml, accounting for variations caused by the body's physiology 12 . ...
Metabolites and antioxidants can be altered in patients with various diseases, particularly in those with cancer. This study aims to measure melatonin and total antioxidant levels in the serum of breast cancer patients and compare them with a healthy control group. Both groups had serum samples collected at 2:00 a.m. and 9:00 a.m. Melatonin levels were determined using High-performance liquid chromatography (HPLC), while total antioxidant levels were assessed by Enzyme-linked immunosorbent assay (ELISA). Levels of melatonin and total antioxidants differed between the groups. In the control group, the levels of melatonin and total antioxidants were considerably greater compared to the diagnostic group, with a p-value of 0.001. Melatonin and total antioxidant levels were consistently greater at 2:00 than at 9:00. The maximum melatonin levels recorded in the diagnostic and control groups were 39.3 pg/mL and 65.9 pg/mL, respectively. Melatonin levels varied based on the age of the participants, with higher amounts observed in younger participants compared to older people in both groups. The BMI affected the levels of melatonin, with a greater BMI leading to elevated melatonin concentrations. The diagnostic group had a total antioxidant level of 39.3 pg/mL, while the control group had a level of 65.9 pg/mL. The elevated levels of melatonin and total antioxidants in the control group indicate a healthy status. The research demonstrated a significant correlation between melatonin and antioxidant levels in breast cancer patients, with reduced melatonin levels and total antioxidant levels in the diagnosed group. Elevated BMI was linked to reduced melatonin levels.
... There are a few studies showing that melatonin may play a role in the pathogenesis of scoliosis, supporting the neuroendocrine hypothesis [20]. Melatonin, as a hormone produced mainly in the pineal gland but also in the retina, is called "the light of the night" since its synthesis and release are stimulated by the darkness and inhibited by the light. ...
Background:
Menarche, as an important parameter in the assessment of scoliosis progression in girls, is proven to be dependent on geographical latitude. The aim of this study was to determine whether the age of menarche differs in scoliotic and non-scoliotic Balkan girls and the relationship between menarche and the laterality of scoliotic curves.
Participants and methods:
This is a retrospective study with three groups: scoliotic, non-scoliotic, and control. Patient data collection and analysis were approved by the Ethical Committee of the Institute.
Statistical analysis:
The SPSS 24 program was used, and we employed One-way ANOVA, Fisher's, and Chi-squared tests to compare different groups. Statistical significance was defined as p < 0.05.
Results:
No statistically significant difference was found in the age of menarche between the three groups (p = 0.168). In the scoliotic postmenarchal group, the primary right curve was dominant in 54.80%, while in the scoliotic premenarchal group, the primary left curve was dominant in 60.09% (p < 0.01).
Conclusion:
In Balkan girls from Bosnia and Herzegovina and Serbia, there was no significant difference in the age of menarche between scoliotic and non-scoliotic girls. A significant difference was found in the laterality of the primary curve in premenarchal and postmenarchal scoliotic girls.
... A variety of well-orchestrated neurochemical processes are involved in controlling the circadian rhythm, especially the light-dark cycle. Melatonin, a hormone known as the 'light of darkness' has the ability to induce a soporific effect and has the capacity to synchronise the sleep-wake cycle [47]. The action of melatonin is controlled by the suprachiasmatic nucleus (SCN) present in the hypothalamus and the sympathetic nervous system, and any disruption in the SCN circadian system is correlated with various sleep disorders [48]. ...
Sleep is a dynamic and controlled set of physiological and behavioural practices during which the stabilisation and restoration processes of the body take place properly. Therefore, sleep disorders, especially chronic insomnia, can harm an individual’s physical and mental health. However, the therapeutic alternatives are limited and possess severe side effects. Thus, in this study, we aimed to investigate the anti-insomnia effect of a polyherbal formulation (Sleep) (SLP) on p-chlorophenyalanine (PCPA) induced insomnia in rats. Intraperitoneal injection of PCPA induced the experimental condition, and the therapeutic effect of SLP was evaluated by studying the sleep pattern and expression of various neurotransmitters and receptors, along with neurotrophins. Moreover, insomnia-associated oxidative stress and inflammation were also studied. From the findings, we found that the SLP-supplemented animals improved their sleeping behaviour and that the major neurotransmitters, hormones, and receptors were maintained at an equilibrium level. Furthermore, the neurotrophin level was increased and pro-inflammatory cytokines were reduced. The evaluation of oxidative stress markers shows that the antioxidants were significantly boosted, and as a result, lipid peroxidation was prevented. The overall findings suggest that SLP can be used as an effective medication for the treatment of sleep disorders like insomnia as it triggers the major neurotransmitter system.
... People may sleep during the day for various reasons, such as the night shift, studying at night, and late-night activities. This may be related to the increased melatonin secretion at night and its breakdown by sunlight [22]. ...
A negative attitude toward sleep has greatly affected sleep habits. In addition to contributing to physical and metabolic disorders, poor sleep quality may cause emotional disturbances. This study aimed to measure sleep behavior and factors contributing to poor sleep quality in the Madinah region, Saudi Arabia. We also assessed whether the use of sleeping aids improved peoples sleep. Three hundred and ninety-nine adults in the Madinah region of Saudi Arabia participated in this cross-sectional study. Three data domains were collected using an online questionnaire between 30 January and 26 April 2022. In the first domain, the characteristics of participants were discussed. In the second domain, questions about sleep behavior were asked. In the third domain, we examined the types, frequency, and impact of sleep aid use. Out of the 399 participants, 154 (38.59%) reported sleep problems. A total of 64.94% of the 154 participants blamed stress as the leading cause of their sleep disorders, and 74.68% of those with sleep problems reported reduced productivity. Among those who reported having sleep problems, 46.10% used sleep aids, with Panadol night (antihistamine) being the most used, 49.30%, followed by Melatonin at 39.44%. Sleep quality improved by 67.6% among those who used sleep aids. A total of 71.8% of the participants think it is not safe to use sleep aids in the long term. Our findings suggest that sleep problems are a prevalent concern in Madinah, Saudi Arabia, and even though the use of sleep aids improved sleep quality, it should be considered an emerging and important public health objective in Saudi Arabia. Further studies are needed to evaluate sleep quality and the level of sleep aid usage among other Saudi Arabian regions.
