Although melatonin is necessary for circadian regulation of sleep, the mechanisms underlying this effect of melatonin are still unclear. In the present study, we showed that melatonin suppressed the activity of GABAergic neurons in the lateral hypothalamus, which has been reported to play a crucial role in maintaining wakefulness.
Disruption to sleep and circadian rhythms can impact on metabolism. The study aimed to investigate the effect of acute sleep deprivation on plasma melatonin, cortisol and metabolites, to increase understanding of the metabolic pathways involved in sleep/wake regulation processes.
The effects of sleep duration on semen quality have been documented in many epidemiological studies. However, the association between sleep quality and semen parameters and reproductive hormones is still unclear.
Poor sleep associates with mental and cardiometabolic pathological outcomes. The participation of sleep timing features in the pathways by which this relationship occurs is not clear.
It was a surprising discovery when mitochondria, as the power houses of cells, were also found to synthesize the potent mitochondrial targeted antioxidant, melatonin. The melatonin synthetic enzyme serotonin N-acetyltransferase (SNAT) was found in matrix and also in the intermembrane space of mitochondria.
To determine the effects of selenium, melatonin, and selenium + melatonin administered for one month on anterior chamber (AC) malondialdehyde (MDA) and AC glutathione (GSH) levels in patients with ocular ischemic syndrome.
Cervical cancer is one of the most common cancers between women and is known as the third leading cause of female cancer related deaths annually. Its detection in early stages allows it to be a preventable and generally treatable disease.
Depression following acute coronary syndrome is prevalent and associated with increased mortality and morbidity. Melatonin may function as a primary prophylactic antidepressant substance and alleviate depressive symptoms. The study was undertaken to determine if melatonin administered following an acute coronary syndrome (ACS) could prevent development of depression.
In depression, symptoms range from loss of motivation and energy to suicidal thoughts. Moreover, in depression alterations might be also observed in the sleep-wake cycle and in the daily rhythms of hormonal (e.g., cortisol, melatonin) secretion.
The development of the endometrium is a cyclic event tightly regulated by hormones and growth factors to coordinate the menstrual cycle while promoting a suitable microenvironment for embryo implantation during the "receptivity window". Many women experience uterine failures that hamper the success of conception, such as endometrium thickness, endometriosis, luteal phase defects, endometrial polyps, adenomyosis, viral infection, and even endometrial cancer; most of these disturbances involve changes in endocrine components or cell damage.
Melatonin (N-acetyl-5-methoxy-tryptamine), which is generally considered as pleiotropic and multitasking molecule, secretes from pineal gland at night under normal light or dark conditions. Apart from circadian regulations, Melatonin also has antioxidant, anti-ageing, immunomodulation and anticancer properties.
Adjuvant chemotherapy for breast cancer (ACBC) has been associated with fatigue, pain, depressive symptoms, and disturbed sleep. And, previous studies in non-cancer patients showed that melatonin could improve the descending pain modulatory system (DPMS).
Several novel animal studies have shown that intrauterine metabolic programming can be modified in the event of reduced melatonin synthesis during pregnancy, leading to glucose intolerance and insulin resistance in the offspring. It is therefore postulated that female night workers when pregnant may expose the offspring to unwanted health threats.
Research focus recently shifted to mitochondrial dynamics and the role of fusion and fission in cardioprotection. The aim of this study was to evaluate (i) the function and dynamics of mitochondria isolated from hearts exposed to ischaemia/reperfusion (I/R) (ii) the effects of melatonin, a powerful cardioprotectant, on mitochondrial dynamics in I/R.
Melatonin, the receptors for which are abundant in the hypothalamic paraventricular nucleus (PVN), can protect the heart from myocardial ischemia-reperfusion (MI/R) injury. The aim of this study was to determine whether the infusion of melatonin into the PVN protects the heart from MI/R injury by suppressing oxidative stress or regulating the balance between proinflammatory cytokines and anti-inflammatory cytokines in MI/R rats.
Melatonin has been shown to reduce oxidative stress and mitigate hypercoagulability. We hypothesized that maternally administered melatonin may reduce placental oxidative stress and hypercoagulability associated with exposure to intrauterine inflammation (IUI) and consequently improve fetoplacental blood flow and fetal sequelae.
Melatonin is a hormone that is secreted by the pineal gland. To date, melatonin is known to regulate the sleep cycle by controlling the circadian rhythm. However, recent advances in neuroscience and molecular biology have led to the discovery of new actions and effects of melatonin.
Studies on circadian timing in depression have produced variable results, with some investigations suggesting phase advances and others phase delays. This variability may be attributable to differences in participant diagnosis, medication use, and methodology between studies.
Sleep disorders increase in prevalence during the menopausal transition and they constitute a complex phenomenon. Insomnia, the main sleep disorder, can be a primary disorder or it can be secondary to hot flushes (HF), mood disorders, psychosocial factors, medical conditions, and other sleep disturbances, such as obstructive sleep apnoea (OSA) or restless legs syndrome (RLS).
Pregnancy is influenced by the circadian ("circa" or approximately; diēm or day) system, which coordinates physiology and behavior with predictable daily changes in the environment such as light/dark cycles.
Women experience increased vulnerability for both mood and sleep disorders, and the female menstrual cycle represents one fundamental mechanism related to risk.
Humans live in a 24-hour environment, in which light and darkness follow a diurnal pattern. Our circadian pacemaker, the suprachiasmatic nuclei (SCN) in the hypothalamus, is entrained to the 24-hour solar day via a pathway from the retina and synchronises our internal biological rhythms.
In this review we summarized the actual clinical data for a cardioprotective therapeutic role of melatonin, listed melatonin and its agonists in different stages of development, and evaluated the melatonin cardiovascular target tractability and prediction using machine learning on ChEMBL.
The Metabolic Syndrome is a cluster of cardio-metabolic risk factors and comorbidities conveying high risk of both cardiovascular disease and type 2 diabetes. It is responsible for huge socio-economic costs with its resulting morbidity and mortality in most countries. The underlying aetiology of this clustering has been the subject of much debate.
Unexplained infertility occurs when common causes for a couple's inability to conceive have been excluded. Although origins of idiopathic infertility are still unclear, factors, such as an altered oxidative balance, are believed to be involved. Melatonin is an outstanding antioxidant reportedly present in the follicular fluid (FF), which has been suggested as a useful tool in the management of human fertility.
Healthy circadian rhythmicity has been suggested to relate to a better state of brain-injured patients and to support the emergence of consciousness in patient groups characterized by a relative instability thereof such as patients with disorders of consciousness (DOC).
Patients with major depressive disorder (MDD) often have circadian rhythm alteration and sleep disturbance. The pineal gland regulates the circadian rhythm and sleep by the secretion of melatonin neurohormone. However, the relationship between pineal abnormality and MDD remains elusive.
We have demonstrated previously that melatonin attenuates hepatotoxicity triggered by high doses of (-)-epigallocatechin-3-gallate (EGCG) in mice. The current work investigated the influence of melatonin on the oncostatic activity of EGCG in two cancer cell lines, wherein melatonin induced an opposite response of p21.
Our purpose is to investigate the impact of circadian and melatonin pathway genes as well as their interactions with night-shift work (NSW) on breast cancer risk in Korean women.
Melatonin, a hormone synthesized by both the pineal gland and retina, functions as an important modulator of a number of physiological functions. In addition to its rather well-established roles in the regulation of circadian rhythms, sleep, and reproduction, melatonin has also been identified as an important regulator of glucose metabolism.
The shortage of donor hearts could be alleviated with the use of the allografts from donation after circulatory death (DCD). Here, we evaluated the protective effect of melatonin on myocardial ischemia/reperfusion (MI/R) injury in a DCD heart model after ex vivo perfusion.
Melatonin has numerous anti-cancer properties reported to influence cancer initiation, promotion, and metastasis. With the need for effective hormone therapies (HT) to treat menopausal symptoms without increasing breast cancer risk, co-administration of nocturnal melatonin with a natural, low-dose HT was evaluated in mice that develop primary and metastatic mammary cancer.
Prevention of neurodegenerative diseases is presently a major goal for our Society and melatonin, an unusual phylogenetically conserved molecule present in all aerobic organisms, merits consideration in this respect.
Last year melatonin was 60 years old, or at least its discovery was 60 years ago. The molecule itself may well be almost as old as life itself. So it is time to take yet another perspective on our understanding of its functions, effects and clinical uses.
Circadian rhythms (CR) are a series of endogenous autonomous oscillators generated by the molecular circadian clock which acting on coordinating internal time with the external environment in a 24-h daily cycle.
Toll-like receptors (TLRs) are crucial activators of inflammatory responses, they are considered immune receptors.
The purpose of this review is to provide a brief summary about the current state of knowledge regarding the circadian rhythm in the regulation of normal renal function.
Daily rhythms generated by endogenous circadian mechanisms and synchronized to the light-dark cycle have been implicated in the timing of birth in a wide variety of species. Although chronodisruption (e.g., shift work or clock gene mutations) is associated with poor reproductive outcomes, little is known about circadian timing during pregnancy.
Molecular circadian clocks align daily behavioral and metabolic rhythms with the external day-night cycle. Priming energy metabolism for recurring changes on a 24-hour basis, these clocks are deeply interlinked with metabolic homeostasis and health.
Melatonin (MLT), a neuromodulator mainly acting through two G-protein coupled receptors MT1 and MT2, regulates many brain functions, including circadian rhythms, mood, pain and sleep. MLT and non-selective MT1/MT2 receptor agonists are clinically used in neuropsychiatric and/or sleep disorders.
Pancreatic cancer has a high mortality rate due to the absence of early symptoms and subsequent late diagnosis; additionally, pancreatic cancer has a high resistance to radio- and chemotherapy. Multiple inflammatory pathways are involved in the pathophysiology of pancreatic cancer.
Non-small-cell lung cancer (NSCLC) is a type of malignancy with progressive metastasis having poor prognosis and lowered survival resulting from late diagnosis. The therapeutic approaches for the treatment of this incurable cancer are chemo- and radiotherapy.
Sleep inertia, broadly defined as decrements in performance and lowering of alertness following waking, lasts for durations ranging between 1 min and 3 hrs. This study investigated whether, compared to a dim light condition (the control), exposure to long-wavelength (red) light delivered to closed eyelids during sleep (red light mask) and to eyes open upon waking (red light goggles) reduced sleep inertia.
Successful pregnancy requires adaptation in maternal physiology. During intrauterine life the mother's circadian timing system supports successful birth and postnatal development. Maternal melatonin is important to transmit circadian timing and day length to the fetus.
The risk of herpes zoster (HZ) increases with age and declining immune function. Increased oxidative stress and inflammatory conditions may cause a negative impact on the immune responses.
Ovarian cancer is one of the most common causes of morbidity related to gynecologic malignancies. Possible risk factors are including hereditary ovarian cancer, obesity, diabetes mellitus, alcohol consumption, aging, and smoking.
The effects of circadian misalignment and work shift on oxidative stress profile of shift workers have not been explored in the literature. The present study aimed to evaluate the role of shift work (day and night) and social jetlag - a measure of circadian misalignment - with oxidative stress markers.
Aging and various age-related diseases are associated with reductions in melatonin secretion, proinflammatory changes in the immune system, a deteriorating circadian system, and reductions in sirtuin-1 (SIRT1) activity.
Disruption of circadian rhythmicity induced by prolonged light exposure, altered sleep patterns and shift work is associated with the development of obesity and related metabolic disorders, including type 2 diabetes and cardiovascular diseases.
Insulin resistance is a main determinant in the development of type 2 diabetes mellitus and a major cause of morbidity and mortality.
Previous research has identified insomnia as a predictor for the onset of depression. The aim of this meta-analysis is to investigate whether insomnia also predicts the onset of other mental disorders.
This study compared urinary 6-sulfatoxymelatonin (aMT6s) over 24 hours among fibromyalgia (FM), major depression disorder (MDD), and healthy control (HC) groups, and examined whether rhythm is correlated with depressive symptoms. To answer this question we compared the rhythm of urinary aMT6s secretion among each group in four time series: morning (06:00-12:00 hours), afternoon (12:00-18:00 hours), evening (18:00-24:00 hours), and night (24:00-06:00 hours). In the FM subjects, we assessed if the rhythm of urinary aMT6s secretion is associated with pain severity, sleep quality, number of trigger points (NTPs), and the pain pressure threshold (PPT).
Preeclampsia remains a leading cause of maternal and perinatal morbidity and mortality. There have been no material advances in the treatment of preeclampsia for nearly 50 years. Combining in vitro studies and a clinical trial, we aimed to determine whether melatonin could be a useful adjuvant therapy.
Melatonin is a lipophilic hormone synthesized and secreted mainly in the pineal gland, acting as a neuroendocrine transducer of photoperiodic information during the night. In addition to this activity, melatonin has shown an antioxidant function and a key role as regulator of physiological processes related to human reproduction.
Heart failure is a multifactorial clinical syndrome characterized by the inability of the heart to pump sufficient blood to the body. Despite recent advances in medical management, poor outcomes in patients with heart failure remain very high. This highlights a need for novel paradigms for effective, preventive and curative strategies.
There is considerable evidence that melatonin may be of use in the prevention and treatment of cancer. This manuscript will review some of the human, animal and cellular studies that provide evidence that melatonin has oncostatic properties.
Oxidative damage to DNA has important implications for human health and has been identified as a key factor in the onset and development of numerous diseases. Thus, it is evident that preventing DNA from oxidative damage is crucial for humans and for any living organism. Melatonin is an astonishingly versatile molecule in this context.
Melatonin is an ancient antioxidant. After its initial development in bacteria, it has been retained throughout evolution such that it may be or may have been present in every species that have existed. Even though it has been maintained throughout evolution during the diversification of species, melatonin’s chemical structure has never changed; thus, the melatonin […]
Oxidative stress is known as a major contributing factor involved in oocyte aging, which negatively affects oocyte quality and development after fertilization. Melatonin is an effective free radical scavenger and its metabolites AFMK and AMK are powerful detoxifiers that eliminate free radicals.
Premature ovarian failure is one of the side effects of chemotherapy in pre-menopausal cancer patients. Preservation of fertility has become increasingly important in improving the quality of life of completely recovered cancer patients.
Good-quality oocytes are critical for the success of in vitro fertilization (IVF), but, to date, there is no marker of ovarian reserve available that can accurately predict oocyte quality.
There is highly credible evidence that melatonin mitigates cancer at the initiation, progression and metastasis phases. In many cases, the molecular mechanisms underpinning these inhibitory actions have been proposed. What is rather perplexing, however, is the large number of processes by which melatonin reportedly restrains cancer development and growth.
What are the underlying mechanisms of the decline in the fertilization ability of post-ovulatory aged oocytes?
Assisted reproductive technologies (ART) have experienced growing interest from infertile patients seeking to become pregnant. The quality of oocytes plays a pivotal role in determining ART outcomes.
Polycystic ovarian syndrome (PCOS) induces anovulation in women of reproductive age, and is one of the pathological factors involved in the failure of in vitro fertilization (IVF).
Melatonin is uncommonly effective in reducing oxidative stress under a remarkably large number of circumstances. It achieves this action via a variety of means: direct detoxification of reactive oxygen and reactive nitrogen species and indirectly by stimulating antioxidant enzymes while suppressing the activity of pro-oxidant enzymes.
The physiology of oocyte in vitro maturation remains elusive. Generally, the oocytes have a very low maturation rate under in vitro conditions.
Melatonin, an indolamine secreted by the pineal gland, is known as a powerful free-radical scavenger and wide-spectrum antioxidant.
The pineal hormone melatonin controls several physiological functions that reach far beyond the regulation of the circadian rhythm. Moreover, it can be produced in extra-pineal organs such as reproductive organs.
Multiple sclerosis (MS) is the most common neurological disease that happens at a young age. MS is an inflammatory disease; associated with the demyelination of the central nervous system.
Evaluating the effectiveness of melatonin in prevention of radiation-induced oral mucositis.
There is currently an urgent need for a viable, cheap, and readily available treatment for the Ebola virus outbreak in West Africa. Here, it is proposed that melatonin may have significant utility in helping the management of this outbreak.
The purpose of this article was to summarize what is known about the function of melatonin in the oral cavity.
Melatonin is a hormone secreted by the enigmatic pineal gland in response to darkness, hence the name hormone of darkness. It has generated a great deal of interest as a therapeutic modality for various diseases particularly sleep disorders.
The purpose of this report is to emphasize the potential utility for the use of melatonin in the treatment of individuals who are infected with the Ebola virus.
The aim of this study was to evaluate the efficacy of oral melatonin supplementation on oocyte and embryo quality in patients in an assisted reproductive technologies program.
Infertility is the problem of 15% of young couples in different societies. One of the factors that could affect fertility is oxidative stress. Therefore, the aim of the present study is to investigate the level of Melatonin, a free radical scavenger, and its correlation with oxidative biomarkers in infertile men.
Melatonin, a versatile molecule, is synthesized by the pineal gland but also by other organs, including gastrointestinal tract, retina, thymus, bone marrow, and by leukocytes.
Melatonin has a wide variety of beneficial actions at the level of the gonads and their adnexa. Some actions are mediated via its classic membrane melatonin receptors while others seem to be receptor-independent.
The reactions of N(1) -acetyl-N(2) -formyl-5-methoxykynuramine (AFMK) and N(1) -acetyl-5-methoxykynuramine (AMK) with (•) OH, (•) OOH, and •OOCCl3 radicals have been studied using the density functional theory.
Melatonin modulates a wide range of physiological functions with pleiotropic effects on the immune system.
The quality of metaphase II oocytes deteriorates rapidly following ovulation as the result of an aging process associated with impaired fertilizing potential, disrupted developmental competence, and increased likelihood of embryonic resorption.
Melatonin (N-acetyl-5-methoxytryptamine) is a multifunctional signaling molecule that has a variety of important functions. Numerous clinical trials have examined the therapeutic usefulness of melatonin in different fields of medicine.
The aim of the study was to evaluate the efficacy of melatonin administration on oocyte quality in women underwent in vitro fertilization (IVF) cycles.
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.
Melatonin is a versatile molecule, synthesized not only by the pineal gland, but also in small amounts by many other organs like retina, gastrointestinal tract, thymus, bone marrow, lymphocytes etc.
The purpose of this study was to evaluate the association between the follicular fluid (FF) reactive oxygen species (ROS) levels, total antioxidant capacity (TAC) and ROS-TAC score and pregnancy after intracytoplasmic sperm injection (ICSI).
The main objective of this study was to detect fatigue-induced clinical symptoms of immune suppression in medical residents. Samples were collected from the subjects at rest, following the first night (low-stress), and the last night (high-stress) of night float.
Bisphenol A (BPA) is a monomer of polycarbonate plastic used to manufacture plastic baby bottles and lining of food cans. It has endocrine-disrupting potential and exerts both toxic and estrogenic effects on mammalian cells.
This study investigated whether melatonin protects luteinized granulosa cells from reactive oxygen species (ROS) as an antioxidant to enhance progesterone production in the follicle during ovulation.
We aimed to analyse the in vitro fertilization-embryo transfer (IVF-ET) outcomes of the patients with sleep disturbances who were administered melatonin.
A worldwide increase in the incidence of obesity indicates the unsuccessful battle against this disorder. Obesity and the associated health problems urgently require effective strategies of treatment.
Although human seminal fluid contains melatonin and spermatozoa reportedly possess membrane melatonin receptors, there are no experimental studies that have ascertained the relationship between melatonin and male infertility.
A recent prospective study indicated that melatonin supplements may reduce the progression of idiopathic scoliosis, the most common deformity of the spine. This form of scoliosis occurs during rapid skeletal growth.
Melatonin is a versatile molecule, synthesized not only in the pineal gland, but also in many other organs. Melatonin plays an important physiologic role in sleep and circadian rhythm regulation, immunoregulation, antioxidant and mitochondrial-protective functions, reproductive control, and regulation of mood.
During the last 20 years, numerous clinical trials have examined the therapeutic usefulness of melatonin in different fields of medicine. The objective of this article is to review, in depth, the science regarding clinical trials performed to date.
Melatonin (N-acetyl-5-methoxytryptamine) has revealed itself as an ubiquitously distributed and functionally diverse molecule. The mechanisms that control its synthesis within the pineal gland have been well characterized and the retinal and biological clock processes that modulate the circadian production of melatonin in the pineal gland are rapidly being unravelled.
Melatonin is a neurohormone produced by the pineal gland that regulates sleep and circadian functions. Melatonin also regulates inflammatory and immune processes acting as both an activator and inhibitor of these responses.
It is commonly accepted that melatonin (N-acetyl-5-methoxytryptamine), the most relevant pineal secretory product, has oncostatic properties in a wide variety of tumors and, especially, in those identified as being hormonedependent.
This review aims at describing the beneficial properties of melatonin related to its antioxidant effects. Oxidative stress, i.e., an imbalance between the production of reactive oxygen species and antioxidant defences, is involved in several pathological conditions such as cardiovascular or neurological disease, and in aging. Therefore, research for antioxidants has developed. However, classical antioxidants often failed to exhibit beneficial effects, especially in metabolic diseases.