Melatonin in postmenopausal females

Melatonin Mediates Osteoblast Proliferation Through the STIM1/ORAI1 Pathway

Based on the positive correlation between bone mineral density and melatonin levels in blood, this study confirmed that melatonin supplementation prevents postmenopausal osteoporosis. We further confirmed that melatonin promotes an increase in intracellular calcium concentrations through the STIM1/ORAI1 pathway, thereby inducing the proliferation of osteoblasts. Introduction: Osteoporosis (OP) is a progressive, systemic bone disease that is one of the main causes of disability and death in elderly female patients. As an amine hormone produced by the human pineal gland, melatonin plays an important role in regulating bone metabolism. This study intends to investigate the relationship between melatonin levels in human blood and bone density and to suggest the efficacy of melatonin in treating osteoporosis by performing in vivo and in vitro experiments. Methods: We used liquid chromatography-tandem mass spectrometry to determine the serum melatonin levels in postmenopausal women with osteoporosis and young women with a normal bone mass. The bone density, BV/TV, Tb.Th, Tb.Sp and other indicators of postmenopausal osteoporosis and mice with a normal bone mass were detected by measuring bone density and micro-CT. The intracellular calcium ion concentration was detected using fluorescence microscopy and a full-wavelength multifunctional microplate reader, and the expression of SOCE-related genes and STIM1/ORAI1 proteins was detected using PCR and WB. Results: This study confirmed that bone density positively correlates with the melatonin level in human blood. In the animal model, melatonin supplementation reverses postmenopausal osteoporosis. We explored the internal mechanism of melatonin treatment of osteoporosis. Melatonin promotes an increase in intracellular calcium ion concentrations through the STIM1/ORAI1 pathway to induce osteoblast proliferation. Conclusions: This study provides an important theoretical basis for the clinical application of melatonin in patients with osteoporosis and helps to optimize the diagnosis and treatment of postmenopausal osteoporosis.

Melatonin and its Relationships with Diabetes and Obesity: A Literature Review

BACKGROUND

Obesity is an important clinical entity, causing many public health issues. Around two billion people in the world are overweight and obese. Almost 40% of American adults are obese and Brazil has about 18 million obese people. Nowadays, 415 million people have diabetes, around 1 in every 11 adults. These numbers will rise to 650 million people within 20 years. Melatonin shows a positive profile on the regulation of the metabolism of the human body.

OBJECTIVE

This study aimed to carry out a broad narrative review of the metabolic profile and associations between melatonin, diabetes and obesity.

METHODS

Article reviews, systematic reviews, prospective studies, retrospective studies, randomized, double-blind, and placebo-controlled trials in humans recently published were selected and analyzed. A total of 368 articles were collated and submitted to the eligibility analysis. Subsequently, 215 studies were selected to compose the content part of the paper, and 153 studies composed the narrative review.

RESULTS

Studies suggest a possible role of melatonin in metabolic diseases such as obesity, T2DM and metabolic syndrome. Intervention studies using this hormone in metabolic diseases are still unclear regarding the possible benefit of it. There is so far no consensus about the possible role of melatonin as an adjuvant in the treatment of metabolic diseases. More studies are necessary to define possible risks and benefits of melatonin as a therapeutic agent.

Melatonin and female hormone secretion in postmenopausal overweight women

Estrogen deficiency is considered to be the main cause of increased appetite and increased weight in postmenopausal women. In this period, reduced secretion of melatonin (MEL) was also observed. The aim of the study was to evaluate the secretion of melatonin, 17-β estradiol and follicle-stimulating hormone (FSH) in relation to body mass index (BMI) in pre- and postmenopausal women. The study included 90 women divided into three equal groups: group I (control)-women without menstrual disorders, group II-postmenopausal women without change in appetite and body weight, group III-postmenopausal women experiencing increased appetite and weight gain. In each patient, serum melatonin, 17-β-estradiol, FSH and urine a 6-sulfatoxymelatonin (aMT6s) were determined. Compared to the control group, the level of melatonin and estradiol was statistically lower. The FSH level was higher than in the groups of postmenopausal women. No significant correlation was found in all groups between the level of melatonin and the levels of estradiol and FSH. A negative correlation was found between aMT6s excretion and BMI, and a positive correlation between the level of FSH and BMI, mainly in overweight women. The obtained results indicate a significant effect of melatonin deficiency on the process of weight gain in postmenopausal women and justify its use in treatment of these disorders.

The effect of melatonin supplementation on the quality of sleep and weight status in postmenopausal women

Aim of the study

We evaluated the effect of melatonin supplementation on the nutritional status of postmenopausal women.

Material and methods

The study included 56 women (51-65 years) and 25 healthy women (27-36 years). The emotional state was assessed using Hamilton Depression Rating Scale (HAM-D), the quality of sleep using Insomnia Severity Index (ISI). Body mass index (BMI) and waist-hip ratio (WHR) were also calculated. The patients were divided into 3 groups: group I (control) – 25 women with normal body weight, group II – 26 postmenopausal women with normal body weight, group III – 30 postmenopausal women with high body weight. In women from group II and III, routine laboratory tests, levels of thyroid-stimulating hormone (TSH), 17β-estradiol, prolactin, follicle-stimulating hormone (FSH) and the concentration of 6-hydroxymelatonin sulphate (6-HMS) in day/night urine fractions were determined. On the day of the examination, women remained on a liquid diet (1800 kcal). Next, a balanced diet of 1500 kcal and 5 mg of melatonin administration were recommended. The follow-up examinations were performed after 4, 8, 12, 16, 20 and 24 weeks.

Results

The patients from groups II and III showed similar mild levels of anxiety and depression and a significant degree of sleep disorders. In group III, lower urinary 6-HMS excretion was observed at night. In both groups a negative correlation was found between urinary 6-HMS excretion and the degree of sleep disorders. After 24 weeks, a statistically significant improvement of quality of sleep was obtained. A negative correlation was detected between urinary 6-HMS excretion and BMI.

Conclusion

Melatonin supplementation contributed to body weight reduction.

Melatonin and the skeleton

Melatonin may affect bone metabolism through bone anabolic as well as antiresorptive effects. An age-related decrease in peak melatonin levels at nighttime is well documented, which may increase bone resorption and bone loss in the elderly. In vitro, melatonin reduces oxidative stress on bone cells by acting as an antioxidant. Furthermore, melatonin improves bone formation by promoting differentiation of human mesenchymal stem cell (hMSC) into the osteoblastic cell linage. Bone resorption is reduced by increased synthesis of osteoprogeterin (OPG), a decoy receptor that prevents receptor activator of NK-κB ligand (RANKL) in binding to its receptor. Moreover, melatonin is believed to reduce the synthesis of RANKL preventing further bone resorption. In ovariectomized as well as nonovariectomized rodents, melatonin has shown beneficial effects on bone as assessed by biochemical bone turnover markers, DXA, and μCT scans. Furthermore, in pinealectomized animals, bone mineral density (BMD) is significantly decreased compared to controls, supporting the importance of sufficient melatonin levels. In humans, dysfunction of the melatonin signaling pathway may be involved in idiopathic scoliosis, and the increased fracture risk in nighttime workers may be related to changes in the circadian rhythm of melatonin. In the so-far only randomized study on melatonin treatment, no effects were, however, found on bone turnover markers. In conclusion, melatonin may have beneficial effects on the skeleton, but more studies on humans are warranted in order to find out whether supplementation with melatonin at bedtime may preserve bone mass and improve bone biomechanical competence.

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

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.

Late, but not early, wake therapy reduces morning plasma melatonin: relationship to mood in Premenstrual Dysphoric Disorder

Wake therapy improves mood in Premenstrual Dysphoric Disorder (PMDD), a depressive disorder in DSM-IV. We tested the hypothesis that the therapeutic effect of wake therapy in PMDD is mediated by altering sleep phase with melatonin secretion. We measured plasma melatonin every 30 min (18:00-09:00 h) in 19 PMDD and 18 normal control (NC) women during mid-follicular (MF) and late luteal (LL) menstrual cycle phases, and during LL interventions with early wake therapy (EWT) (sleep 03:00-07:00 h)(control condition) vs. late wake therapy (LWT) (sleep 21:00-01:00 h)(active condition). Melatonin offset was delayed and duration was longer in the symptomatic LL vs. asymptomatic MF phase in both NC and PMDD subjects. LWT, but not EWT, advanced offset and shortened duration vs. the LL baseline, although they improved mood equally. Later baseline LL morning melatonin offset was associated with more depressed mood in PMDD patients, and longer melatonin duration in the MF phase predicted greater mood improvement following LWT. That LWT, but not EWT, advanced melatonin offset and shortened duration while they were equally effective in improving mood suggests that decreasing morning melatonin secretion is not necessary for the therapeutic effects of wake therapy in PMDD.

Increased melatonin and delayed offset in menopausal depression: role of years past menopause, follicle-stimulating hormone, sleep end time, and body mass index

CONTEXT

The constellation of endocrine patterns accompanying menopausal depression remains incompletely characterized.

OBJECTIVE

Our objective was to test the hypothesis that the amplitude or phase (timing) of melatonin circadian rhythms differs in menopausal depressed patients (DP) vs. normal controls women (NC).

DESIGN

We measured plasma melatonin every 30 min from 1800-1000 h in dim light (<30 lux) or dark, serum gonadotropins and steroids (1800 and 0600 h), and mood (Hamilton and Beck depression ratings).

SETTING

The study was conducted at a university hospital.

PARTICIPANTS AND SETTING

Twenty-nine (18 NC, 11 DP) peri- or postmenopausal women participated.

MAIN OUTCOME MEASURES

We measured plasma melatonin (onset, offset, synthesis offset, duration, peak concentration, and area under the curve) and mood.

RESULTS

Multi- and univariate analyses of covariance showed that melatonin offset time was delayed (P = 0.045) and plasma melatonin was elevated in DP compared with NC (P = 0.044) across time intervals. Multiple regression analyses showed that years past menopause predicted melatonin duration and that melatonin duration, body mass index, years past menopause, FSH level, and sleep end time were significant predictors of baseline Hamilton (P = 0.0003) and Beck (P = 0.00004) depression scores.

CONCLUSIONS

Increased melatonin secretion that is phase delayed into the morning characterized menopausal DP vs. NC. Years past menopause, FSH, sleep end time, and body mass index may modulate effects of altered melatonin secretion in menopausal depression.

Sleep, rhythms and women's mood. Part II. Menopause

This review summarizes studies of sleep and other biological rhythms in menopausal women with major depression compared with healthy control subjects. Where feasible, we focused on studies in women who met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) criteria for a major depressive episode (MDE) compared with matched normal control subjects and the Staging System for Reproductive Aging in Women (STRAW) criteria. The aim was to review supporting evidence for the hypothesis that a disruption of the normal temporal relationship between sleep and other biological rhythms, such as melatonin, cortisol, thyroid stimulating hormone (TSH) or prolactin, occur during the menopausal transition. As a result, depressive disorders occur in predisposed women. Treatment strategies, designed to correct these altered phase (timing) or amplitude abnormalities, thereby improve mood. Although there may be some common features to menopausal depression compared with other depressive disorders related to the reproductive cycle (e.g. premenstrual dysphoric disorder or postpartum major depression), such as increased morning melatonin secretion, a specific profile of sleep and biological rhythms may distinguish healthy from depressed women during menopause. Further work is needed to characterize more fully the particular abnormalities associated with well-defined menopausal depression in order to develop treatment strategies targeted more specifically to pathogenesis.

The effect of exogenous melatonin administration on trabecular width, ligament thickness and TGF-β1 expression in degenerated intervertebral disk tissue in the rat

Intervertebral disk (IVD) degeneration, a complex pathological condition of varying origins, causes low back pain. Degenerative changes in IVD tissue affect the adjacent vertebral structure, resulting in a decreased vertebral trabecular width. It has been suggested that transforming growth factor-beta 1 (TGF-beta(1)) may have a role in the repair of connective tissue, as it occurs in the IVD degeneration process. In this study, we investigated the effects of exogenous melatonin (MEL) administration on vertebral trabecular width, ligament thickness and TGF-beta(1) expression in degenerated IVD tissue. Fifteen adult male Swiss Albino rats were divided randomly into three groups; nonoperated control, operated degeneration, and MEL treatment groups. In the operated degeneration and MEL treatment groups, cuts were made parallel to the end plates in the posterior annulus fibrosus at the fifth and tenth vertebral segments of the tail to induce IVD degeneration. In each group, TGF-beta(1) immunoreactivity and morphometry of vertebral trabecular width and anterior and posterior ligament thickness were evaluated. Histologically, disorganisation and irregularity of collagen fibres was seen in the degenerated (operated) IVD. Increased TGF-beta(1) expression in multinuclear chondrocytes was also observed as was decreased vertebral trabecular width. Importantly, the reduction of trabecular width observed in the operated degenerated group was reversed after MEL administration (p<0.0001). Similarly, TGF-beta(1) expression in multinuclear chondrocytes was dramatically increased after exogenous MEL application. Thus, there was a regression in histopathological changes after MEL treatment, with disk appearances similar to those of the control group. Based on our findings, we suggest that MEL activates the recovery process in the degenerated IVD tissue, possibly by stimulating TGF-beta(1) activity. This is the first report investigating the involvement of the pineal hormone MEL in the repair of rat IVD.

Serial transvaginal sonography of a case of complete hydatidiform mole

Sonography has achieved a position of preeminence in the diagnostic evaluation of molar gestation. However, little information is available about the serial change of the transvaginal sonographic features of molar pregnancy. We describe a case of complete hydatidiform mole, and present serial transvaginal views taken during the early gestational period.

The diagnostic implications of routine ultrasound examination in histologically confirmed early molar pregnancies

OBJECTIVE

Early ultrasound examination is being used increasingly in the diagnosis of molar pregnancy. The aim of this study was to examine the diagnostic implications of routine ultrasound examination for histologically confirmed molar pregnancies.

METHODS

This was a retrospective review of sonographic and histological findings in a series of consecutive cases referred to the National Trophoblastic Disease Surveillance Centre with suspected molar pregnancies. In 194 cases referred to the center over a 6-month period in whom results of a preceding ultrasound examination were documented, review of ultrasound findings and final histological diagnosis was carried out.

RESULTS

There were 155 cases with a reviewed histological diagnosis of complete or partial hydatidiform mole. In 131 (67%) cases, the sonographic diagnosis was that of a missed miscarriage/anembryonic pregnancy with no documented suspicion of molar pregnancy, referral being on the basis of histological examination of products of conception. In 63 cases, ultrasound examination suggested molar pregnancy; in 53 (84%) of these, the diagnosis of molar pregnancy was correct. Overall, 37 of 64 (58%) complete moles had sonographic evidence of molar pregnancy compared to 16 of 91 (17%) partial moles. Of 155 histologically confirmed complete or partial hydatidiform moles, only 53 (34%) were suspected as molar sonographically.

CONCLUSION

The majority of cases of molar pregnancy now present as missed miscarriage/anembryonic pregnancy sonographically, highlighting the importance of histological examination to diagnose gestational trophoblastic disease.