Melatonin in perimenopausal and postmenopausal women: associations with mood, sleep, climacteric symptoms, and quality of life

Melatonin: Current evidence on protective and therapeutic roles in gynecological diseases

Melatonin, a potent antioxidant and free radical scavenger, has been demonstrated to be effective in gynecological conditions and female reproductive cancers. This review consolidates the accumulating evidence on melatonin's multifaceted protective effects in different pathological contexts. In gynecological conditions such as endometriosis, polycystic ovary syndrome (PCOS), and uterine leiomyoma, melatonin has shown promising effects in reducing oxidative stress, inflammation, and hormonal imbalances. It inhibits adhesion molecules' production, and potentially mitigates leukocyte adherence and inflammatory responses. Melatonin's regulatory effects on hormone production and insulin sensitivity in PCOS individuals make it a promising candidate for improving oocyte quality and menstrual irregularities. Moreover, melatonin exhibits significant antitumor effects by modulating various signaling pathways, promoting apoptosis, and suppressing metastasis in breast cancers and gynecological cancers, including ovarian, endometrial, and cervical cancers. Furthermore, melatonin's protective effects are suggested to be mediated by interactions with its receptors, estrogen receptors and other nuclear receptors. The regulation of clock-related genes and circadian clock systems may also contribute to its inhibitory effects on cancer cell growth. However, more comprehensive research is warranted to fully elucidate the underlying molecular mechanisms and establish melatonin as a potential therapeutic agent for these conditions.

Effects of melatonin intake on depression and anxiety in postmenopausal women: a systematic review and meta-analysis of randomised controlled trials

We conducted a systematic review and meta-analysis of randomised controlled trials (RCTs) evaluating the effects of melatonin intake on depression and anxiety in postmenopausal women. To identify RCTs examining the effect of melatonin supplementation on depression and anxiety scores in postmenopausal women, a comprehensive electronic search was conducted via the Cochrane Central Register of Controlled Trials, Science direct, Google Scholar, PubMed, Medline, Scopus and Web of Science databases using the keywords ("melatonin" OR "N-acetyl serotonin") AND ("menopause" OR "climacteric") AND ("depression" OR "anxiety"). The search strategy was applied to articles published between January 2000 and April 2023. The Cochrane tool was used to evaluate the bias risk in RCTs. For the meta-analysis, fixed effect models and random effect models were employed based on heterogeneity. Preferred Reporting Items for Systematic Reviews and Meta-Analysis in Our Study guidelines were followed. Five RCTs were included in the study, with a total sample size of 441 (experimental: 227 and control: 214). When the effect of melatonin use on depression in menopausal women was analysed, it was found that melatonin significantly reduced menopausal depression (SMD - 0.166, CI =  - 0.288/ - 0.045, p < 0.05). When the effect of melatonin use on anxiety in postmenopausal women was analysed, it was found that melatonin significantly improved menopausal anxiety (SMD - 0.806, CI = 1.491/ - 0.120, p < 0.05). Melatonin is promising as a potential treatment to help depression and anxiety in the postmenopausal period. More high-quality studies are needed to determine their safety.

Association of oxidative balance score with sleep quality: NHANES 2007-2014

BACKGROUND

Oxidative stress is correlated with sleep quality. A common tool for evaluating dietary and lifestyle exposures to oxidative stress is the Oxidative Balance Score (OBS), with higher OBS suggesting more substantial antioxidant exposures. The relationship between OBS and sleep quality is unclear. Investigating the association between OBS and sleep quality was the purpose of this study.

METHODS

To figure out the relationship between OBS and sleep quality, we utilized weighted linear models and weighted logistic regression. Adjusted models were also examined.

RESULTS

6300 participants who took part in the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2014 were recruited. OBS was negatively associated with sleep disorder (OR: 0.97; 95 % CI: 0.94-0.99), and positively associated with sleep duration (MD: 0.02; 95%CI: 0.01-0.03). Within the range of OBS > 24, each unit increase in OBS will result in a 40 % reduction in sleep disorder, and a 26 % increasement in sleep duration after adjustment (all P for trend <0.05). Dietary and lifestyle components were closely related to sleep quality independently. The relationship between OBS and sleep quality was prominent in the female population under 50 years of age. After stratification by education level, this relationship persisted.

LIMITATION

This research was cross-sectional design, and it was not possible to deduce causality.

CONCLUSION

Diet and lifestyle might influence sleep quality by modulating oxidative balance. Antioxidant diets and lifestyles were important in reducing sleep problems and our study also provided new ideas for improving sleep quality.

Influence of Melatonin Treatment on Emotion, Sleep, and Life Quality in Perimenopausal Women: A Clinical Study

Method

100 healthy perimenopausal women were recruited and randomly assigned to two groups, with 50 subjects in each group. In the control group, placebo was administrated daily for 3 cycles (4 weeks of treatment for 1 cycle and drug withdrawals for 1 week). The study group received 3 mg oral melatonin treatment daily in the same period of time. All subjects completed the study. We compared the uterine volume, endometrial thickness, LH (luteinizing hormone), FSH (follicle generating hormone), E2 (estradiol), and melatonin levels during daytime between the two groups before and after the study. Moreover, perimenopause syndrome, sleep, mood, and QoL were analyzed at the baseline and 3 cycles by the questionnaires of the Kupperman index, the Pittsburgh sleep quality index (PSQI), the Hamilton anxiety scale (HAMA), and the Hamilton depression scale (HAMD), as well as menopausal QoL (MENQOL), respectively. Any adverse reactions experienced by the subjects were also compared in the study. Finally, 91 participants (92%) completed the whole study, 47 and 44 in the study and control groups, respectively, and their data were considered in subsequent analyses.

Results

After therapy, the two groups were similar in the uterine volume and endometrial thickness. In contrast to the control group, the study group showed notably decreased LH and FSH levels. No notable difference was discovered in E2 and melatonin levels between the two groups in the study. Moreover, the study group exhibited a significantly lower score in the Kupperman index, PSQI, HAMA, HAMD, and MENQOL scale than the control group. Moreover, the two groups had no notable difference in adverse reactions.

Conclusion

Melatonin was a useful treatment to relieve climacteric symptoms and improve sleep, mood, and life quality in perimenopausal women without obvious adverse reactions.

Combination of Soy Isoflavones, 8-Prenylnaringenin and Melatonin Improves Hot Flashes and Health-Related Quality of Life Outcomes in Postmenopausal Women: Flavie Study

OBJECTIVES

This study aims to investigate the effects of a combination of soy isoflavones, 8-prenylnaringenin (8-PN), and melatonin in postmenopausal women suffering from moderate-to-severe hot flashes (HFs).

METHODS

A multicenter, prospective, open-label study enrolled 44 postmenopausal women suffering from moderate-to-severe HFs (≥ 5 daily or ≥ 35 weekly) to receive 54.4 mg standardized soy isoflavones (including 24.5 mg genistein and 16.3 mg daidzein), 100 µg 8-PN, and 1 mg melatonin once daily for 12 weeks. The primary clinical outcomes included changes in health-related quality of life (HRQoL) scores (Menopause-Specific QoL questionnaire [MENQoL] and Cervantes Scale) and HFs following 4 and 12 weeks of treatment. Other analyses included treatment adherence, acceptability, tolerability, and safety.

RESULTS

All of the four domains of MENQoL questionnaire significantly improved at 4 weeks (P < 0.05) and 12 weeks (P < 0.001), affecting significantly the vasomotor, psychosocial, and physical spheres (41.2%, 26.3%, and 25.0%; 12 weeks improvements, respectively). Similarly, in the menopause (39.3%) and psychic (51.7%) domains (both P < 0.05 at 12 weeks), the global score of the Cervantes Scale significantly increased at 4 weeks (18.6%) and 12 weeks (35.4%). Accordingly, moderate-to-severe HFs significantly decreased at 4 weeks compared to baseline (41.7% reduction) and further reduced at 12 weeks (76.5%), including the total number of episodes.

CONCLUSIONS

Food supplements containing soy isoflavones, 8-PN, and melatonin showed an early and progressive benefit for reducing clinically significant HFs and for improving HRQoL across all domains, favorably affecting postmenopausal women's overall well-being.

Sex differences in the effects of sleep disorders on cognitive dysfunction

Sleep is an essential physiological function that sustains human life. Sleep disorders involve problems with the quality, duration, and abnormal behaviour of sleep. Insomnia is the most common sleep disorder, followed by sleep-disordered breathing (SDB). Sleep disorders often occur along with medical conditions or other mental health conditions. Of particular interest to researchers is the role of sleep disorders in cognitive dysfunction. Sleep disorder is a risk factor for cognitive dysfunction, yet the exact pathogenesis is still far from agreement. Little is known about how sex differences influence the changes in cognitive functions caused by sleep disorders. This narrative review examines how sleep disorders might affect cognitive impairment, and then explores the sex-specific consequences of sleep disorders as a risk factor for dementia and the potential underlying mechanisms. Some insights on the direction of further research are also presented.

The effect of oral capsule of Ocimum basilicum leaf extract on sleep quality and insomnia severity in menopausal women: A randomized clinical trial

One of the complications of menopause is sleep disorders, which affect women's health. Ocimum basilicum contains compounds that may affect sleep. The aim of this study was to determine the effect of an oral capsule of O. basilicum leaf extract on sleep quality and the severity of insomnia in menopausal women. This triple-blind, randomized clinical trial study was performed on 60 Iranian menopausal women aged 40 to 65 years. Subjects were randomly assigned into two groups of intervention (each capsule containing 250 mg of O. basilicum extract and 250 mg Avicel) per day for 1 month and placebo. The Pittsburgh Sleep Quality and Insomnia Intensity Index were used to assess sleep quality and severity of insomnia before, 2 weeks after and 1 month after the intervention. There was no statistically significant difference in the baseline variables between the intervention and placebo groups (p > .05). The total sleep quality scores in the two groups of intervention and placebo were 6.2 ± 0.3 versus 9.3 ± 0.3 (p < .001) and 3.7 ± 0.3 versus 9.1 ± 0.3 (p = .015) 2 weeks and 1 month after the intervention, respectively. The total insomnia severity scores in the two groups of intervention and placebo were 9.0 ± 0.3 versus 12.1 ± 0.3 (p < .001) and 5.6 ± 0.5 versus 11.0 ± 0.5 (p < .001) 2 weeks and 1 month after the intervention, respectively. Consumption of O. basilicum capsules improved sleep quality and insomnia in menopausal women. This study was approved (code IR.MUMS.NURSE.REC.1398.070) by the Ethic committee of Mashhad University of Medical Sciences and registered at the Iranian Registry of Clinical Trials, with the No. IRCT20200104046001N1 in January 2020.

Chronotype and Sleep Quality in Obesity: How Do They Change After Menopause?

PURPOSE OF REVIEW

This review primarily provides an overview of the current evidence on chronotype (which reflects an individual's preference for the timing of sleeping, eating, and activity in a 24-h period) and sleep quality changes in obesity in postmenopausal women. It also explores possible nutritional strategies to manage these changes in this phase of a woman's life.

RECENT FINDINGS

Menopause is a life stage frequently associated with sleep disturbances and changes in circadian rhythms. Sleep disturbances are one of the main symptoms of menopause and are caused by several factors such as hormonal changes, obesity, and melatonin reduction. In addition, the chronotype also changes following menopause. Nutritional strategies are essential because they could help manage menopausal sleep disturbances and circadian misalignment, particularly by tackling obesity and overweight. In the management of postmenopausal women, especially those experiencing obesity, careful assessment of sleep disturbances and chronotype and subsequent development of the most appropriate treatment, including nutritional management, should be part of the treatment routine.

The role of melatonin in the development of postmenopausal osteoporosis

Melatonin is an important endogenous hormone that modulates homeostasis in the microenvironment. Recent studies have indicated that serum melatonin levels are closely associated with the occurrence and development of osteoporosis in postmenopausal women. Exogenous melatonin could also improve bone mass and increase skeletal strength. To determine the underlying mechanisms of melatonin in the prevention and treatment of postmenopausal osteoporosis, we performed this review to analyze the role of melatonin in bone metabolism according to its physiological functions. Serum melatonin is related to bone mass, the measurement of which is a potential method for the diagnosis of osteoporosis. Melatonin has a direct effect on bone remodeling by promoting osteogenesis and suppressing osteoclastogenesis. Melatonin also regulates the biological rhythm of bone tissue, which benefits its osteogenic effect. Additionally, melatonin participates in the modulation of the bone microenvironment. Melatonin attenuates the damage induced by oxidative stress and inflammation on osteoblasts and prevents osteolysis from reactive oxygen species and inflammatory factors. As an alternative drug for osteoporosis, melatonin can improve the gut ecology, remodel microbiota composition, regulate substance absorption and maintain metabolic balance, all of which are beneficial to the health of bone structure. In conclusion, our review systematically demonstrates the effects of melatonin on bone metabolism. Based on the evidence in this review, melatonin will play a more important role in the diagnosis, prevention and treatment of postmenopausal osteoporosis.

A Degradable and Osteogenic Mg-Based MAO-MT-PLGA Drug/Ion Delivery System for Treating an Osteoporotic Fracture

Osteoporotic fractures are a very common bone disease that is difficult to completely cure. A large number of people worldwide suffer from pain caused by osteoporotic fractures every year, which can even cause disability and death. The compromised skeletal strength, lower density, trabecular microstructure, and bone-forming ability caused by osteoporotic fractures make them difficult to treat relative to normal fractures. An ideal scheme for osteoporotic fractures is to select internal fixation materials with matched mechanical and biological properties and carry anti-osteoporosis drugs on the plant to achieve bio-fixation and improve the condition of osteoporosis simultaneously. We designed a Mg-based MAO-MT-PLGA drug/ion delivery system (DDS) compatible with bone-like mechanical properties, degradation properties, and drug therapy. In this research, we evaluated the degradation behavior of Mg-based MAO-MT-PLGA DDS using immersion tests and electrochemical tests aided by SEM, EDS, XPS, XRD, and FT-IR. The DDS showed better corrosion resistance over Mg alloy and could release more Mg2+ due to the degradation of PLGA. According to cell viability and cell adhesion, the DDS showed better osteogenic characteristics over control group I (Mg alloy) and control group II (Mg-based MAO alloy), especially in the cells co-cultured with the leaching solution for 72 h, in which the DDS group increased to about 15% cell viability compared with group I (p < 0.05). The mRNA relative expressions, including ALP, collagen I, OCN, OPG, and Runx-2, as well as extracellular matrix calcium deposits of the DDS, are 1.5~2 times over control group I and control group II (p < 0.05), demonstrating a better ability to promote bone formation and inhibit bone resorption. After the DDS was implanted into the castrated rat model for one month, the trabeculae in the treatment group were significantly denser and stronger than those in the control group, with a difference of about 1.5 times in bone volume fraction, bone density, and the number of trabeculae, as well as the magnesium content in the bone tissue (p < 0.05). The above results demonstrated that the Mg-based MAO-MT-PLGA drug/ion delivery system is a potential treatment for osteoporotic fractures.

Skin, hair and beyond: the impact of menopause

The skin is an endocrine organ and a major target of hormones such as estrogens, androgens and cortisol. Besides vasomotor symptoms (VMS), skin and hair symptoms often receive less attention than other menopausal symptoms despite having a significant negative effect on quality of life. Skin and mucosal menopausal symptoms include dryness and pruritus, thinning and atrophy, wrinkles and sagging, poor wound healing and reduced vascularity, whereas skin premalignant and malignant lesions and skin aging signs are almost exclusively caused by environmental factors, especially solar radiation. Hair menopausal symptoms include reduced hair growth and density on the scalp (diffuse effluvium due to follicular rarefication and/or androgenetic alopecia of female pattern), altered hair quality and structure, and increased unwanted hair growth on facial areas. Hormone replacement therapy (HRT) is not indicated for skin and hair symptoms alone due to the risk-benefit balance, but wider potential benefits of HRT (beyond estrogen's effect on VMS, bone, breast, heart and blood vessels) to include skin, hair and mucosal benefits should be discussed with women so that they will be able to make the best possible informed decisions on how to prevent or manage their menopausal symptoms.

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.

Sex and Gender Science: The World Writes on the Body

Sex and Gender Science seeks to better acknowledge that the body cannot be removed from the world it inhabits. We believe that to best answer any neuroscience question, the biological and the social need to be addressed through both objective means to learn, "how it is like" and subjective means to learn, "what it is like." We call bringing the biological and social together, "Situated Neuroscience" and the mixing of approaches to do so, Very Mixed Methods. Taken together, they constitute an approach to Sex and Gender Science. In this chapter, we describe neural phenomena for which considering sex and gender together produces a fuller knowledge base: sleep, pain, memory, and concussion. For these brain phenomena examples, studying only quantitative measures does not reveal the full impact of these lived experiences on the brain but studying only the qualitative would not reveal how the brain responds. We discuss how Sex and Gender Science allows us to begin to bring together biology and its social context and acknowledge where context can contribute to resolving ignorance to offer more expansive, complementary, and interrelating pictures of an intricate neuro-landscape.

The Crosstalk between Melatonin and Sex Steroid Hormones

Melatonin, an indolamine mainly released from the pineal gland, is associated with many biological functions, namely, the modulation of circadian and seasonal rhythms, sleep inducer, regulator of energy metabolism, antioxidant, and anticarcinogenic. Although several pieces of evidence also recognize the influence of melatonin in the reproductive physiology, the crosstalk between melatonin and sex hormones is not clear. Here, we review the effects of sex differences in the circulating levels of melatonin and update the current knowledge on the link between sex hormones and melatonin. Furthermore, we explore the effects of melatonin on gonadal steroidogenesis and hormonal control in females. The literature review shows that despite the strong evidence that sex differences impact on the circadian profiles of melatonin, reports are still considerably ambiguous, and these differences may arise from several factors, like the use of contraceptive pills, hormonal status, and sleep deprivation. Furthermore, there has been an inconclusive debate about the characteristics of the reciprocal relationship between melatonin and reproductive hormones. In this regard, there is evidence for the role of melatonin in gonadal steroidogenesis brought about by research that shows that melatonin affects multiple transduction pathways that modulate Sertoli cell physiology and consequently spermatogenesis, and also estrogen and progesterone production. From the outcome of our research, it is possible to conclude that understanding the correlation between melatonin and reproductive hormones is crucial for the correction of several complications occurring during pregnancy, like preeclampsia, and for the control of climacteric symptoms.

Menopause and sleep disorders

Women are likely to suffer from sleep disorders more in comparison to men during menopause and with advancing age. The incidence of sleep disorders ranges from 16% to 47% at peri-menopause and 35%–60% at postmenopause. Insomnia with or without associated anxiety or low lying depression and Mood disorder is most common associated manifestations. Sleep disorders and insomnia largely remain a clinical diagnosis based on the subjective complaints of patients. Benzodiazepines remain the mainstay of the treatment in majority of the sleep disorders including chronic or acute insomnia. Treatment of associated anxiety, depression, or psychosis is most important. Tricyclic antidepressant, Selective Serotonin Reuptake Inhibitors (SSRI), Melatonin, Duloxetine, Fluoxetine, Imipramine, Nortriptyline or Amitriptyline and other drugs such as Eszopiclone, Escitalopram, Gabapentin, Quiteiapine, Citalopram, Mirtazapine followed by long-acting Melatonin and Ramelteon, also are very useful for the management of various sleep disorders. Hormone replacement therapy presently lacks concrete evidence to be used in menopausal women for sleep disorder. Sleep hygiene practices, self-hypnosis, meditation, and exercise play a very important role.

Melatonin in neuroskeletal biology

Osteoporosis and neurodegenerative diseases are common diseases in the aging population. Studies demonstrate the complex communication among skeletal, muscular, and nervous systems and point to the emerging roles of neuromuscular systems in bone homeostasis. The discovery that the nervous system directly regulates bone remodeling implies that osteoporosis is a neuroskeletal disease. Melatonin, a hormone secreted from the pineal gland, is a melatonin receptor 1A (MT1) and 1B (MT2) agonist and influences the function of diverse systems. Melatonin is a pharmaceutical ingredient in numerous medicines, over-the-counter medicines, nutraceuticals, and dietary supplements, which benefit disease prevention and treatment, including osteoporosis and neurodegenerative diseases. This review aims to summarize the recent advances in preventing senile, postmenopausal, and neurodegenerative osteoporosis with melatonin and provide new insights into how neuromuscular systems influence bone homeostasis. More preclinical and clinical studies in neuroskeletal biology will eventually improve the lives of people fighting osteoporosis.

A cross-sectional study on the relationship between meditation training and emotional intelligence in women

AIM

We aimed to reveal the relationship of meditation with emotional intelligence (EI), sleep quality and melatonin level.

DESIGN

A cross-sectional study.

METHODS

Our current research was performed on middle-aged women. EI scale, Pittsburgh Sleep Quality Index (PSQI) and night-time saliva melatonin were measured for 65 participants including 33 meditators and 32 controls.

RESULTS

The meditation group showed a significantly higher EI score than the control group. In the regression analysis between EI and age, only the meditation group showed a significant positive correlation. The Pearson correlation analysis among all participants revealed a significant negative correlation between PSQI and EI. There was no significant group difference in the melatonin and PSQI.

Sleep and endocrine therapy in breast cancer

Sleep disturbances and insomnia are common among breast cancer survivors, and can have a significant effect on quality of life and numerous other significant outcomes. Among risks for sleep disturbance is the introduction of anti-estrogen endocrine therapies. The possible contributing factors to sleep disturbance in endocrine therapy are complex, and include pre-existing sleep disorders, the effects of chemotherapy and other treatments, and concurrent symptoms such as hot flashes. In addition, sleep disturbance in menopause, the natural downregulation of reproductive hormones in older age, is a common occurrence, and can offer a model for understanding the high prevalence of sleep problems in breast cancer survivors on endocrine therapy, as well as suggesting possible treatments such as behavioral interventions and pharmaceuticals. Altogether, significantly more research is needed to better understand and address sleep disturbance in breast cancer survivors on endocrine therapy in order to support quality of life and treatment adherence.

Effects of exogenous melatonin on sleep quality and menopausal symptoms in menopausal women: a systematic review and meta-analysis of randomized controlled trials

IMPORTANCE

Because of the bothersome symptoms during women's menopausal period and the severe side effects of hormone therapy, it is meaningful to find new breakthroughs in improving menopausal women's quality of life.

OBJECTIVE

We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) evaluating melatonin intake on the improvement of sleep quality, general menopausal symptom, mood states, as well as interaction of estradiol levels and body mass index (BMI) in menopausal women.

EVIDENCE REVIEW

We used the search terms "melatonin" together with "menopause" or "post-menopause" or "peri-menopause" in multiple databases online including PubMed, Web of Science, Embase, Clinical trial, Cochrane Library, and China National Knowledge Infrastructure from the first publication year to October 2020. Interesting data included characteristics of the study design, study participants, intervention, and outcome measures. Risk of biases in RCTs was evaluated with the Cochrane tool. Fixed-effect models and random-effect models were used for meta-analysis according to heterogeneity. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed in our study.

FINDINGS

Eight cohorts (n = 812) evaluating the effects of melatonin in menopausal women were included. Melatonin was used in every study with differences existing in dose (1 mg - 5 mg) and duration (3 to 12 mo). Improved physical symptoms (standard mean difference [SMD] -0.376; 95% CI, -0.599 to -0.153, P = 0.001) merged in four RCTs. Melatonin treatment resulted in no benefits to sleep quality (SMD -0.659; 95% CI, -1.535 to 0.217, P = 0.141) and general menopause symptoms (SMD -0.625; 95% CI, -1.354 to 0.105, P = 0.093) in four and three RCTs, respectively. More specifically, melatonin did not solve the psychological (SMD -0.026; 95% CI, -0.372 to 0.321, P = 0.884, I2 = 70.3%), sexual (SMD -0.661; 95% CI, -1.416 to 0.093, P = 0.086) and vasomotor (SMD -0.256; 95% CI, -0.701 to 0.188, P = 0.258) issues. No significant changes were observed in anxiety (SMD 0.018; 95% CI, -0.519 to 0.556, P = 0.946), depression (SMD 0.133; 95% CI, -0.435 to 0.702, P = 0.646), BMI (weighted mean difference 0.029 kg/m2; 95% CI, -0.183 to 0.240, P = 0.790) or estradiol levels (weighted mean difference 0.016 pg/mL; 95% CI, -1.220 to 1.252, P = 0.980).

CONCLUSIONS

Melatonin seems to improve physical symptoms in menopausal women, but the general menopausal symptoms, sleep quality, mood state, estradiol levels, and BMI did not improve under melatonin intervention. However, multiple large-scale clinical randomized trials are needed to validate our conclusions.

Nighttime melatonin secretion and sleep architecture: different associations in perimenopausal and postmenopausal women

BACKGROUND

Sleep quality typically decreases after menopause, but the underlying mechanisms are poorly understood. Concentrations of melatonin are lower and its secretion profiles different before and after menopause. However, whether and how melatonin and sleep architecture are associated in women of different reproductive states have not been examined to date.

METHODS

Overnight serum melatonin samples were taken from 17 perimenopausal and 18 postmenopausal healthy women. Sleep quality was measured with all-night polysomnography recordings.

RESULTS

Melatonin concentrations tended to be the lowest during NREM sleep, and were associated with higher odds of transitions from wake to NREM sleep. The curves of predicted overnight melatonin values from linear mixed models varied according to sleep phases (NREM, REM, Wake) in perimenopausal, but not in postmenopausal women. In perimenopause higher melatonin area under curve (AUC) correlated with higher slow-wave activity (p = 0.043), and higher minimum concentrations with shorter slow-wave sleep (SWS) latency (p = 0.029). In postmenopause higher mean and maximum melatonin concentrations and AUC correlated with lower SWS percentage (p = 0.044, p = 0.029, p = 0.032), and higher mean (p = 0.032), maximum (p = 0.032) and minimum (p = 0.037) concentrations with more awakenings from REM sleep. In the age- and BMI- adjusted regression models, the association between higher maximum (p = 0.046) melatonin concentration and lower SWS percentage remained.

CONCLUSIONS

The relationship between melatonin and sleep architecture differed in perimenopausal and postmenopausal women. After menopause, high melatonin concentrations were associated with worse sleep. Whether these different patterns are related to aging of the reproductive system, and to decrease in menopausal sleep quality, remains to be elucidated.

A practical nutritional guide for the management of sleep disturbances in menopause

Sleep disturbances (SD) represent one of the main symptoms of menopause and they are caused by several factors. Hormonal changes such as the reduction of oestrogen levels and the consequent vasomotor symptoms (VMS) along with psychiatric disorders such as depression and anxiety could contribute to the onset of SD. Furthermore, obesity per sè or through the obstructive sleep apnoea (OSA) could blunt sleep. Moreover, in menopause is usual a reduction in melatonin, that could contribute to SD. Nutritional strategies are paramount because they could contribute to manage menopause-related SD, in particular tackling obesity and overweight. Furthermore, some foods, such as soy, fish, whole grains, vegetables and fruit could decrease symptoms like depression and VMS, correlated with SD in postmenopausal women. Therefore, the aim of this review is to provide an overview of the current evidence on SD in menopause and to provide nutritional strategies for managing SD in this context.

The value of melatonin supplementation in postmenopausal women with Helicobacter pylori-associated dyspepsia

BACKGROUND

Dyspeptic syndrome is particularly common in postmenopausal women in the form of epigastric pain. The aim of the study was to assess the role of melatonin in chronic dyspepsia in this group of women, and examine the role of Helicobacter infection.

METHODS

The study comprised 152 subjects including 30 healthy women (Group I), 60 women with asymptomatic H.pylori infection (Group II), and 64 women with H. pylori infection with chronic dyspepsia (Group III). Endoscopic examination was performed, as well as histological assessment of gastric end duodenal mucosa, urease breath test (UBT-13C), and immunoenzymatic assessment of serum 17-β-estradiol, follicle stimulating hormone and melatonin, and urinary 6-sulfatoxymelatonin. In Group III, 14-day antibacterial treatment was introduced with pantoprazole, amoxicillin and levofloxacin followed a six-month treatment with placebo in 32 women (Group IIIa), and melatonin 1 mg/morning and 3 mg/at bedtime in the other 32 women (Group IIIb).

RESULTS

No significant differences were found between serum level of female hormone. Serum melatonin levels were similar between Group I (12.5 ± 2.72 pg/ml) and Group II (10.5 ± 3.73 pg/ml; p > 0,05). The level was significantly lower in Group III (5.72 ± 1.42 pg/ml; p < 0.001). Eradication of H.pylori was obtained in 75.0% women in Group IIIa, and in 84.3% in Group IIIb (p > 0.05). After six months, dyspeptic symptoms resolved in 43.7% patients in Group IIIa and 84.3% in Group IIIb (p < 0.001).

CONCLUSION

Melatonin supplementation is useful in treating H. pylori-associated dyspepsia, particularly in postmenopausal women with lower levels of this hormone.

TRIAL REGISTRATION

NCT04352062, date of registration: 15.04.2020.

Effect of short-term intermittent exposure to waterborne estradiol on the reproductive physiology of the round goby (Neogobius melanostomus)

The objective of this study was to determine how the short-term exposure to a supraphysiological concentration of waterborne 17β-estradiol (E₂) influences on melatonin (Mel) and thyroxine (T₄) concentrations in plasma and E₂ and 11-ketotestosterone (11-KT) concentrations in plasma and gonads in both sexes of round goby (Neogobius melanostomus) during the pre-spawning, spawning, late spawning and non-spawning phases. The experimental protocol was based on short-term, repeated exposures of fish to a supraphysiological dose of waterborne E₂. Mel level was unchanged on exposure to E₂ during the investigated phases, and its role in determining a time frame for spawning in both sexes of round goby seems to be stable in those conditions. T₄ and sex steroids (E₂ and 11-KT) were sensitive to the exposure of E₂, and those changes influence gonads by accelerating oocyte development, ovulation and regression and inhibiting spermatogenesis in this species. The results demonstrate that the physiological responses of fish in all investigated phases were altered over a short window of exposure, indicating that short-term exposure to a supraphysiological dose of E₂ may impact fish in the wild. Furthermore, round goby can be recommended as a very suitable model for studying endocrine disruptors, which is sensitive to even short exposure to E₂.

Insomnia and menopause: a narrative review on mechanisms and treatments

The menopausal transition is associated with an increased frequency of sleep disturbances. Insomnia represents one of the most reported symptoms by menopausal women. According to its pathogenetic model (3-P Model), different predisposing factors (i.e. a persistent condition of past insomnia and aging per se) increase the risk of insomnia during menopause. Moreover, multiple precipitating and perpetuating factors should favor its occurrence across menopause, including hormonal changes, menopausal transition stage symptoms (i.e. hot flashes, night sweats), mood disorders, poor health and pain, other sleep disorders and circadian modifications. Thus, insomnia management implies a careful evaluation of the psychological and somatic symptoms of the individual menopausal woman by a multidisciplinary team. Therapeutic strategies encompass different drugs but also behavioral interventions. Indeed, cognitive behavioral therapy represents the first-line treatment of insomnia in the general population, regardless of the presence of mood disorders and/or vasomotor symptoms (VMS). Different antidepressants seem to improve sleep disturbances. However, when VMS are present, menopausal hormone therapy should be considered in the treatment of related insomnia taking into account the risk-benefit profile. Finally, given its good tolerability, safety, and efficacy on multiple sleep and daytime parameters, prolonged-released melatonin should represent a first-line drug in women aged ≥ 55 years.

Role of Ovarian Hormones in the Modulation of Sleep in Females Across the Adult Lifespan

Ovarian hormones, including 17β-estradiol, are implicated in numerous physiological processes, including sleep. Beginning at puberty, girls report more sleep complaints than boys, which is maintained throughout the reproductive life stage. Sleep problems are exacerbated during the menopausal transition, evidenced by greater risk for sleep disorders. There is emerging evidence that menopause-associated hormone loss contributes to this elevated risk, but age is also an important factor. The extent to which menopause-associated sleep disturbance persists into postmenopause above and beyond the effects of age remains unknown. Untreated sleep disturbances have important implications for cognitive health, as they are emerging as risk factors for dementia. Given that sleep loss impairs memory, an important knowledge gap concerns the role played by menopause-associated hormone loss in exacerbating sleep disturbance and, ultimately, cognitive function in aging women. In this review, we take a translational approach to illustrate the contribution of ovarian hormones in maintaining the sleep-wake cycle in younger and middle-aged females, with evidence implicating 17β-estradiol in supporting the memory-promoting effects of sleep. Sleep physiology is briefly reviewed before turning to behavioral and neural evidence from young females linking 17β-estradiol to sleep-wake cycle maintenance. Implications of menopause-associated 17β-estradiol loss is also reviewed before discussing how ovarian hormones may support the memory-promoting effects of sleep, and why menopause may exacerbate pathological aging via effects on sleep. While still in its infancy, this research area offers a new sex-based perspective on aging research, with a focus on a modifiable risk factor for pathological aging.

Melatonin Patterns and Levels During the Human Menstrual Cycle and After Menopause

Context

Melatonin may play a role in the regulation of the human menstrual cycle and may decline with menopause and/or aging.

Objective

The objective of this work is to investigate the relations between melatonin and the menstrual cycle, menopause, and aging.

Methods

This was a cross-sectional and longitudinal analysis of 20 participants from the Study of Women’s Health Across the Nation (SWAN) Daily Hormone Study (DHS). The outcome measure was first-morning urine assay of 6-sulfatoxymelatonin (aMT6s), a gauge of melatonin. For each participant, aMT6s was measured daily during one premenopausal cycle with evidence of luteal activity (ELA) and one postmenopausal collection with no evidence of luteal activity (NELA).

Results

In addition to the organized patterns of hormone metabolites (estrone conjugates [E1c], and pregnanediol glucuronide [PdG]) and gonadotropins that characterized ovulatory menstrual cycles, there was a late luteal rise in aMT6s. In NELA collections, there was no periodicity of E1c, PdG, gonadotropins, or aMT6s. The strongest predictors of aMT6s levels were PdG values 11 to 12 days prior to aMT6s (β = 1.46, P = .001 and β = 1.44, P = .001, respectively). E1c and gonadotropins were not statistically significantly associated with aMT6s. Mean aMT6s in premenopause was 53.5 ng/mL, greater than the mean of 37.4 ng/mL in postmenopausal samples from the same women (P = .0002).

Conclusions

This study confirms a late luteal melatonin rise, likely signaled by progesterone, which may influence menstrual cycle pacemaker control. Melatonin declined from premenopause to postmenopause. A high correlation between menopause transition stage and age precludes distinction between the influences of ovarian and chronological aging.

Depressive Symptoms, Sleep Profiles and Serum Melatonin Levels in a Sample of Breast Cancer Patients

BACKGROUND

Chronobiological changes have been detected in various physiological functions of patients with breast cancer, suggesting dysregulation in the pineal gland and melatonin secretion. This study aimed to assess and measure serum melatonin levels pre- and postoperatively in patients who had been diagnosed for the first time with breast cancer.

METHODS

A sample of first-time breast cancer patients, consisting of 45 women aged 25-65 years, was evaluated and psychometric assessment was completed using the Beck Depression Inventory (BDI), Insomnia Severity Index (White, Weinberg et al) and the Epworth Sleepiness Scale (Cardoso, Spence et al). The Morningness-Eveningness questionnaire (MEQ) was used to assess the chronotype. Serum melatonin levels were measured by radioimmunoassay.

RESULTS

Morning and moderately morning chronotypes were prevalent among the sample (25%, 45.8%, respectively). The finding of a mean BDI score of 13.5±11.2 indicated that depressive symptoms were prevalent among the sample. Despite the finding that a mean of the participants apparently had no symptoms of daytime sleepiness (the mean and standard deviations of the ESS were 7.5±4.4), scores on the ISI (a mean of 16.7±SD 7.3) indicated that insomnia symptoms were prevalent in the sample. Melatonin levels showed an inverse relationship with insomnia severity as measured by the ISI and depression severity, as assessed by the BDI. The postoperative melatonin levels were higher than the preoperative levels. Additionally, the psychometric profile differed among various pathological types of breast cancer according to their hormone receptor profile.

CONCLUSION

Serum melatonin levels correlated significantly with self-reported sleep quality and psychometric profiles of depression in the present sample of breast cancer patients. The melatonin assay, which is relatively easy to carry out, provided a convenient, objective measure of an important biological correlate of sleep quality and depression. This assay thus represented a confirmatory alternative to the self-report instruments, which may sometimes be unreliable. Future studies should further evaluate the utility of melatonin measures in psychiatric and sleep complaints of breast cancer patients.

Monthly variation of hot flashes, night sweats, and trouble sleeping: effect of season and proximity to the final menstrual period (FMP) in the SWAN Menstrual Calendar substudy

OBJECTIVE

Although reproductive function is influenced by season, few studies have evaluated seasonal effects on menopausal symptoms. We assessed the impact of season and proximity to the final menstrual period (FMP) on frequency of symptom reporting.

METHODS

In all, 955 participants in the Study of Women's Health Across the Nation recorded whether or not they had experienced menopausal symptoms on a monthly menstrual calendar over a 10-year period. We modeled the log-odds of presence of a given symptom each month using a logistic mixed-effects model, assuming a third-order polynomial before the FMP and a different third-order polynomial after the FMP. We assumed sine and cosine functions for month of the year.

RESULTS

Five to 10 years before the FMP, ∼20% of women reported hot flashes and night sweats, whereas ∼40% reported trouble sleeping. Prevalence rose ∼4 years before the FMP with a sharp jump in hot flash (∼60%) and night sweats (∼40%) prevalence coincident with the FMP. Peaks in hot flashes and trouble sleeping were observed in July with troughs in January. The peak and trough in night sweats occurred about 1 month earlier. Odds of hot flashes, night sweats, and trouble sleeping were 66%, 50%, and 24% greater, respectively, at the seasonal peak versus the seasonal minimum.

CONCLUSION

Menopausal symptoms exhibit seasonal variation associated with the summer and winter equinoxes. Seasonal increases in night sweats precede increases in hot flashes. Prospectively recorded monthly symptom data demonstrate that hot flashes and night sweats increase notably coincident with the FMP. : Video Summary:http://links.lww.com/MENO/A476.

Melatonin and Female Reproduction: An Expanding Universe

For more than a half century the hormone melatonin has been associated with vertebrate reproduction, particularly in the context of seasonal breeding. This association is due in large measure to the fact that melatonin secretion from the pineal gland into the peripheral circulation is a nocturnal event whose duration is reflective of night length, which of course becomes progressively longer during winter months and correspondingly shorter during the summer months. The nocturnal plasma melatonin signal is conserved in essentially all vertebrates and is accessed not just for reproductive rhythms, but for seasonal cycles of metabolic activities, immune functions, and behavioral expression. A vast literature on melatonin and vertebrate biology has accrued over the past 60 years since melatonin's discovery, including the broad topic of animal reproduction, which is far beyond the scope of this human-focused review. Although modern humans in the industrialized world appear in general to have little remaining reproductive seasonality, the relationships between melatonin and human reproduction continue to attract widespread scientific attention. The purpose of this chapter is to draw attention to some newer developments in the field, especially those with relevance to human fertility and reproductive medicine. As the vast majority of studies have focused on the female reproductive system, a discussion of the potential impact of melatonin on human male fertility will be left for others.

Endocrine profile of the VCD-induced perimenopausal model rat

During the transition to menopause, women experience a variety of physical and psychological symptoms that are directly or indirectly linked to changes in hormone secretion. Establishing animal models with intact ovaries is essential for understanding these interactions and finding new therapeutic targets. In this study, we assessed the endocrine profile, as well as the estrous cycle, in the 4-vinylcyclohexene diepoxide (VCD)-induced follicular depletion rat model in 10-day intervals over 1 month to accurately establish the best period for studies of the transition period. Twenty-eight-day-old female rats were injected daily with VCD or oil s.c. for 15 days and euthanized in the diestrus phase approximately 70, 80, 90 and 100 days after the onset of treatment. The percentage of rats showing irregular cycles and the plasma level of FSH increased only in the 100-day VCD group. Plasma anti-Müllerian hormone (AMH) and progesterone were lower in all VCD groups compared to control groups, while estradiol remained unchanged or higher. As in control groups, dihydrotestosterone (DHT) progressively decreased in the 70-90-day VCD groups; however, it was followed by a sharp increase only in the 100-day VCD group. No changes were found in plasma corticosterone, prolactin, thyroid hormones or luteinizing hormone. Based on the estrous cycle and endocrine profile, we conclude that 1) the time window from 70 to 100 days is suitable to study a perimenopause-like state in this model, and 2) regular cycles with low progesterone and AMH and normal FSH can be used as markers of the early/mid-transition period, whereas irregular cycles associated with higher FSH and DHT can be used as markers of the late transition period to estropause.

[The role of melatonin as a component of the antioxidant defense system in perimenopausal women with insomnia]

AIM

To determine the ethnic features of the functioning of the 'lipid peroxidation-antioxidants' system and to evaluate the role of melatonin as one of the antioxidant defense system components in Caucasian and Asian perimenopausal women with insomnia.

MATERIAL AND METHODS

One hundred and ten perimenopausal women divided into Caucasian (Russian ethnic group (n=60)) and Asian (Buryat ethnic group (n=50)) were studied. All women underwent clinical-anamnestic examination. Diagnoses of insomnia and obstructive sleep apnea syndrome (OSAS) were made according to the results of specialized somnological questionnaires and polysomnographic monitoring. A multidimensional discriminant analysis was used to reveal the most informative parameters among the hormonal and metabolic parameters studied (melatonin 06.00-07.00h; 12.00-13.00h; 18.00-19.00h; 23.00-00.00h; lipid profile, lipid peroxidation and antioxidant defense system).

RESULTS

The most informative indicators of the metabolic system in Caucasians with insomnia are morning, evening, night melatonin, ketodienes and conjugated trienes, oxidized glutathione (GSSG); with insomnia and OSAS: morning, day, night melatonin, substrates with conjugated double bonds, total cholesterol; in Asian women with insomnia: evening, night melatonin, superoxide dismutase activity (SOD), diene conjugates, active products of thiobarbituric acid, cholesterol of very low density lipoproteins; in women with insomnia and OSAS: morning, day melatonin, SOD, GSSG. The recalculation of the informativeness of each attribute as a percentage showed the prevalence of the influence of the antioxidant protection system parameters over those of lipid peroxidation processes. The contribution of melatonin to the total share of the antioxidant protection system components is more than 60%.

CONCLUSION

Both in Caucasian and Asian women with sleep disorders, there is stress in the antioxidant defense system, where melatonin is the largest contributor.

Co-administering Melatonin With an Estradiol-Progesterone Menopausal Hormone Therapy Represses Mammary Cancer Development in a Mouse Model of HER2-Positive Breast Cancer

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. Individually, melatonin (MEL) and estradiol-progesterone therapy (EPT) did not significantly affect mammary cancer development through age 14 months, but, when combined, the melatonin-estradiol-progesterone therapy (MEPT) significantly repressed tumor formation. This repression was due to effects on tumor incidence, but not latency. These results demonstrate that melatonin and the HT cooperate to decrease the mammary cancer risk. Melatonin and EPT also cooperate to alter the balance of the progesterone receptor (PR) isoforms by significantly increasing PRA protein expression only in MEPT mammary glands. Melatonin significantly suppressed amphiregulin transcripts in MEL and MEPT mammary glands, suggesting that amphiregulin together with the higher PRA:PRB balance and other factors may contribute to reducing cancer development in MEPT mice. Melatonin supplementation influenced mammary morphology by increasing tertiary branching in the mouse mammary glands and differentiation in human mammary epithelial cell cultures. Uterine weight in the luteal phase was elevated after long-term exposure to EPT, but not to MEPT, indicating that melatonin supplementation may reduce estrogen-induced uterine stimulation. Melatonin supplementation significantly decreased the incidence of grossly-detected lung metastases in MEL mice, suggesting that melatonin delays the formation of metastatic lesions and/or decreases aggressiveness in this model of HER2⁺ breast cancer. Mammary tumor development was similar in EPT and MEPT mice until age 8.6 months, but after 8.6 months, only MEPT continued to suppress cancer development. These data suggest that melatonin supplementation has a negligible effect in young MEPT mice, but is required in older mice to inhibit tumor formation. Since melatonin binding was significantly decreased in older mammary glands, irrespective of treatment, melatonin supplementation may overcome reduced melatonin responsiveness in the aged MEPT mice. Since melatonin levels are known to decline near menopause, nocturnal melatonin supplementation may also be needed in aging women to cooperate with HT to decrease breast cancer risk.

INSOMNIA AND CIRCADIAN RHYTHMS OF MELATONIN IN MENOPAUSAL WOMEN

The aim of the review is to analyze literature data about sleep homeostasis and the role of the one of circadian system key elements – melatonin – in the regulation of the sleep-wake cycle in women in menopause. It was shown that the prevalence and structure of sleep disorders depends on the menopausal phase. It was revealed that the melatonin content in the body, determined in various biological media (blood, saliva, urine), depends on age, sex, race, and chronotype. It was shown that morning melatonin can be used as a biological marker for determining the chronotype. Most studies indicated a decrease in melatonin level with aging. Moreover, women have lower melatonin level than men. In case of insomnia, lower melatonin level was found, although the results of the studies are ambiguous. The shift in the peak of hormone secretion in the early morning hours was described in menopausal women. Also, the dependence of melatonin circadian rhythm on the menopausal phase was revealed, which determines different approaches to insomnia therapy. We revealed the association of melatonin secretion circadian rhythms with Clock 3111T/C gene polymorphism in Caucasian patients with insomnia, which allows considering 3111T allele as risky in the formation of melatonin circadian rhythm disturbances in these patients.

Mechanism of melatonin combined with calcium carbonate on improving osteoporosis in aged rats

The effects of melatonin and calcium carbonate on aged rats with osteoporosis (OP) were assessed. Forty female Sprague-Dawley (SD) rats aged 15 months were randomly divided into a model group (group OP), melatonin group (group M), calcium carbonate group (group Ca) and melatonin combined with calcium carbonate group (group M+Ca), while 10 rats aged 3 months were set as the control group (group NC). The changes of bone density and bone mineral level of lumbar vertebra and bilateral femur in rats of each group were observed. The levels of serum calcium, phosphorus, superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) in rats of each group were determined. Compared with those in group NC, bone density of lumbar vertebra and bilateral femur and bone mineral level were distinctly reduced, serum calcium and activities of SOD and GSH-Px were obviously decreased, and MDA content was remarkably increased in rats of groups OP, M and Ca; the differences were statistically significant (P<0.05 or P<0.01); compared with that in group OP, bone density of lumbar vertebra and bilateral femur and bone mineral level were remarkably increased, serum calcium and activities of SOD and GSH-Px were obviously increased, and MDA content was remarkably decreased in rats of groups M, Ca and M+Ca; the differences were statistically significant (P<0.05 or P<0.01); compared with those in groups M and Ca, bone density of lumbar vertebra and bilateral femur and bone mineral level were obviously elevated, serum calcium and activities of SOD and GSH-Px were evidently elevated, and MDA content was remarkably decreased in rats of group M+Ca; the differences were statistically significant (P<0.05). Melatonin and calcium carbonate can significantly improve antioxidative ability in rats with osteoporosis, increase bone density, elevate serum calcium level and reduce bone mineral loss, thus preventing and treating osteoporosis, and the combination displays more remarkable effects.

Measuring serum melatonin in postmenopausal women: Implications for epidemiologic studies and breast cancer studies

BACKGROUND

Circulating melatonin is a good candidate biomarker for studies of circadian rhythms and circadian disruption. However, epidemiologic studies on circulating melatonin are limited because melatonin is secreted at night, yet most epidemiologic studies collect blood during the day when melatonin levels are very low, and assays are lacking that are ultrasensitive to detect low levels of melatonin reliably.

OBJECTIVE

To assess the performance of a refined radioimmunoassay in measuring morning melatonin among women.

METHODS

We used morning serum samples from 47 postmenopausal women ages 48-80 years without a history of breast cancer who participated in the San Francisco Bay Area Breast Cancer Study, including 19 women who had duplicate measurements. The coefficient of variation (CV) and intraclass coefficient (ICC) were estimated using the random effect model.

RESULTS

Reproducibility for the assay was satisfactory, with a CV of 11.2% and an ICC of 98.9%; correlation between the replicate samples was also high (R = 0.96). In the 47 women, serum melatonin levels ranged from 0.6 to 62.6 pg/ml, with a median of 7.0 pg/ml.

CONCLUSION

Our results suggest that it is possible to reliably measure melatonin in postmenopausal women in morning serum samples in large epidemiologic studies to evaluate the role of melatonin in cancer etiology or prognosis.

Association of the melatonin circadian rhythms with clock 3111T/C gene polymorphism in Caucasian and Asian menopausal women with insomnia

A comparative analysis of melatonin circadian rhythms in Caucasian (incoming population) and Asian (indigenous population) menopausal women with/without sleep disorders depending on the genotype of Clock 3111T/C gene polymorphism was realized.The melatonin level in the saliva was determined four times a day (6:00-7:00, 12:00-13:00, 18:00-19:00, 23:00-00:00 h). The Caucasian women-carriers of the TT-genotype with insomnia as compared to control group-had a higher morning melatonin level and a lower night melatonin level. The Asian women with TT-genotype and insomnia had a lower levels of melatonin as compared to control at daytime, evening and night. A significantly higher melatonin level in the early morning hours was detected in the Caucasian women-carriers of the TT-genotype with insomnia as compared to group womencarriers of the minor 3111C-allele. There were no statistically significant differences in the circadian rhythms of melatonin in the Asian women depending on the genotype of the Clock 3111T/C polymorphism. An assumption with respect to the protective role of the minor allele 3111C in the development of insomnia associated with the displacement of melatonin circadian rhythms in the representatives of the incoming population was made.

Sleep problems during the menopausal transition: prevalence, impact, and management challenges

A substantial number of women experience sleep difficulties in the approach to menopause and beyond, with 26% experiencing severe symptoms that impact daytime functioning, qualifying them for a diagnosis of insomnia. Here, we review both self-report and polysomnographic evidence for sleep difficulties in the context of the menopausal transition, considering severity of sleep complaints and links between hot flashes (HFs) and depression with poor sleep. Longitudinal population-based studies show that sleep difficulties are uniquely linked with menopausal stage and changes in follicle-stimulating hormone and estradiol, over and above the effects of age. A major contributor to sleep complaints in the context of the menopausal transition is HFs, and many, although not all, HFs are linked with polysomnographic-defined awakenings, with HF-associated wake time contributing significantly to overall wakefulness after sleep onset. Some sleep complaints may be comorbid with depressive disorders or attributed to sleep-related breathing or movement disorders, which increase in prevalence especially after menopause, and for some women, menopause, age, and environmental/behavioral factors may interact to disrupt sleep. Considering the unique and multifactorial basis for sleep difficulties in women transitioning menopause, we describe clinical assessment approaches and management options, including combination treatments, ranging from cognitive behavioral therapy for insomnia to hormonal and nonhormonal pharmacological options. Emerging studies suggest that the impact of severe insomnia symptoms could extend beyond immediate health care usage and quality of life issues to long-term mental and physical health, if left untreated in midlife women. Appropriate treatment, therefore, has immediate benefit as well as advantages for maintaining optimal health in the postmenopausal years.

Protective effects of melatonin on long-term administration of fluoxetine in rats

The degree and consequence of tissue injury are highly regarded during long-term exposure to selective antidepressant fluoxetine. Melatonin has been shown to palliate different lesions by scavenging free radicals, but its role in the reduction of the fluoxetine-induced injuries has been little known. Thirty-six mature male Wistar rats were randomly assigned into control and experimental groups. The experimental rats were included as following; 24mg/kg/bw fluoxetine for 4 weeks; 1mg/kg/bw melatonin for 4 weeks; fluoxetine+1-week melatonin, fluoxetine+2-week melatonin and fluoxetine+4-week melatonin. In the current experiment, we investigated weight gain, hematological and biochemical parameters, pathological injuries and oxidative status. We noted the positive effect of melatonin in weight loss of fluoxetine-treated rats (p<0.05). The significant reduction of superoxide dismutase, glutathione peroxidase, catalase activities in blood, liver, and kidneys and changes in serum total antioxidant capacity caused by fluoxetine were reversed by melatonin (p<0.05). Melatonin reduced the increased lipid peroxidation and transaminase activity in rats received fluoxetine (p<0.05). We also showed the potency of fluoxetine in inducing leukopenia, thrombocytopenia and hypochromic and macrocytic anemia which was blunted by melatonin. Both RBCs and platelets indices were also corrected. Rats received melatonin in combination with fluoxetine showed a reduction in the severity of degeneration and inflammatory changes in different tissues, brain, heart, liver, lungs, testes and kidneys as compared to the fluoxetine group. Therefore, melatonin fundamentally reversed the side effects of fluoxetine in the rat model which is comparable to human medicine.

Sleep, Melatonin, and the Menopausal Transition: What Are the Links?

The pineal hormone Melatonin plays an important role in the regulation of the circadian sleep/wake cycle, mood, and perhaps immune functions, carcinogensis and reproduction. The human circadian rhythm of melatonin release from the pineal gland is tightly synchronized with the habitual hours of sleep. Peri- and postmenopausal women often complain of difficulties initiating and/or maintaining sleep, with frequent nocturnal and early morning awakenings. In this review we discuss the pathophysiology of melatonin function as it relates to sleep disorders in menopausal women, highlighting the potential use of exogenous melatonin during the menopausal transition and beyond.

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: shedding light on infertility?--A review of the recent literature

In recent years, the negative impact of oxidative stress on fertility has become widely recognised. Several studies have demonstrated its negative effect on the number and quality of retrieved oocytes and embryos following in-vitro fertilisation (IVF). Melatonin, a pineal hormone that regulates circadian rhythms, has also been shown to exhibit unique oxygen scavenging abilities. Some studies have suggested a role for melatonin in gamete biology. Clinical studies also suggest that melatonin supplementation in IVF may lead to better pregnancy rates. Here we present a critical review and summary of the current literature and provide suggestions for future well designed clinical trials.

Risk of depressive disorder following non-alcoholic cirrhosis: a nationwide population-based study

BACKGROUND & AIMS

To evaluate the risk of depressive disorders among non-alcoholic patients by using the Taiwan National Health Insurance Research Database (NHIRD).

METHODS

We conducted a retrospective study of a matched cohort of 52 725 participants (10 545 non-alcoholic cirrhotic patients and 42 180 control patients) who were selected from the NHIRD. Patients were observed for a maximum of 11 years to determine the rates of newly onset depressive disorders, and Cox regression was used to identify the risk factors associated with depressive disorders in cirrhotic patients.

RESULTS

During the 11-year follow-up period, 395 (3.75%) non-alcoholic cirrhotic patients and 1 183 (2.80%) control patients were diagnosed with depressive disorders. The incidence risk ratio of depressive disorders between non-alcoholic cirrhotic patients and control patients was 1.76 (95% CI, 1.57-1.98, P<.001). After adjusting for age, sex, and comorbidities, non-alcoholic cirrhotic patients were 1.75 times more likely to develop depressive disorders (95% CI, 1.56-1.96, P<.001) compared with the control patients. The hazard ratios for patients younger than 60 years old (1.31) and female (1.25) indicated that each is an independent risk factor for depressive disorders in non-alcoholic cirrhotic patients.

CONCLUSIONS

The likelihood of developing depressive disorders is greater among non-alcoholic cirrhotic patients than among patients without cirrhosis. Symptoms of depression should be sought in patients with cirrhosis.

The effect of hormone therapy on serum melatonin concentrations in premenopausal and postmenopausal women: a randomized, double-blind, placebo-controlled study

OBJECTIVES

Melatonin levels decrease physiologically with age, and possibly with the transition to menopause. The plausible influence of hormone therapy (HT) on melatonin is poorly understood. The aim of this randomized, placebo-controlled, double-blind trial was to investigate the effect of HT administration on serum melatonin concentrations in late premenopausal and postmenopausal women.

STUDY DESIGN

Analyses were carried out among 17 late premenopausal and 18 postmenopausal healthy women who participated in a prospective HT study in Finland. Serum melatonin was sampled at 20-min (21:00-24:00 h; 06:00-09:00 h) and 1-h (24:00-06:00 h) intervals at baseline and after 6 months with HT or placebo.

MAIN OUTCOME MEASURES

Melatonin levels and secretion profile after 6 months of HT compared to placebo.

RESULTS

Mean melatonin levels, mean melatonin exposure level (area under curve, AUC) and mean duration of melatonin secretion did not differ after 6 months with HT vs. placebo, irrespectively of the reproductive state. However, in postmenopausal women the melatonin peak time (acrophase) was delayed by 2.4h (2 h 21 min) on average after 6 months with HT vs. placebo (p<0.05). No interaction between time and group was detected when melatonin level was modelled before or after treatment.

CONCLUSIONS

Administration of HT to postmenopausal women alters melatonin peak time, but not melatonin levels. Further research on larger clinical samples is needed to better understand the effects of HT on melatonin profile.