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

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.

Insomnia in Postmenopausal Women: How to Approach and Treat It?

Insomnia is one of the major complaints of menopausal women with advancing age and may be complexly related to a variety of causes. However, there is still a lack of standards on the general approach and treatment for insomnia in menopausal women. The aim of this review is to summarize recent pathogenic theories of sleep disturbance in the menopausal period and discuss the approach and management of insomnia in postmenopausal women. Sleep disturbances in menopausal women may be associated with physical and psychiatric factors and other comorbid diseases. Careful history taking and multidisciplinary physical and psychosocial evaluation are necessary and, in particular, comorbidities related to sleep disorders, such as obstructive sleep apnea, must be taken into consideration. A unique aspect of insomnia in postmenopausal women is that menopausal symptoms due to hormonal decline can be closely related to sleep disturbances. Therefore, menopausal hormone therapy (MHT) should be considered as the treatment of choice among pharmacological treatments following cognitive behavioral therapy, which is suggested as the first-line treatment in the general population insomnia treatment guidelines. Additionally, melatonin and 5HT-based drugs, which have fewer side effects, along with MHT should be preferentially recommended in menopausal women.

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.

Night shift hormone: How does melatonin affect depression?

Melatonin is the main hormone secreted by the pineal gland that modulates the circadian rhythm and mood. Previous studies have shown the therapeutic effects of melatonin, or its important analogue, agomelatine, on depression. In this review study, we aimed to discuss the potential mechanisms of melatonin involved in the treatment of depression. It was noted that disrupted circadian rhythm can lead to depressive state, and melatonin via regulating circadian rhythm shows a therapeutic effect. It was also noted that melatonin induces antidepressant effects via promoting antioxidant system and neurogenesis, and suppressing oxidative stress, neuroinflammation, and apoptosis. The interaction effect between melatonin or agomelatine and serotonergic signaling has a significant effect on depression. It was noted that the psychotropic effects of agomelatine are induced by the synergistic interaction between melatonin and 5-HT_2C receptors. Agomelatine also interacts with glutamatergic signaling in brain regions involved in regulating mood and circadian rhythm. Interestingly, it was concluded that melatonin exerts both pro- and anti-inflammatory effects, depending on the grade of inflammation. It was suggested that synergistic interaction between melatonin and 5-HT_2C receptors may be able to induce therapeutic effects on other psychiatric disorders. Furthermore, dualistic role of melatonin in regulating inflammation is an important point that can be examined at different levels of inflammation in animal models of depression.

Melatonin Alleviates Ovariectomy-Induced Cardiovascular Inflammation in Sedentary or Exercised Rats by Upregulating SIRT1

We aimed to evaluate the impact of hormone replacement, melatonin, or exercise alone or their combination on oxidative damage and functional status of heart, brain, and aorta of ovariectomized (OVX) rats and to determine whether the signaling pathway is dependent on sirtuin-1 (SIRT1). Ovariectomized Sprague Dawley rats were orally given either a hormone replacement therapy (1 mg/kg/day,17β estradiol; HRT) or melatonin (4 mg/kg/day) or HRT + melatonin treatments or tap water, while each group was further divided into sedentary and exercise (30 min/5 days/week) groups. After the heart rate measurements and memory tests were performed, trunk blood was collected at the end of the 10th week to determine metabolic parameters in serum samples. Tissue samples of abdominal aorta, heart, and brain were taken for biochemical measurements and histopathological evaluation. Heart rates and memory performances of the OVX rats were not changed significantly by none of the applications. Melatonin treatment or its co-administration with HRT upregulated the expressions of IL-10 and SIRT1, reduced the expressions of IL-6 and TNF-α, and reduced DNA damage in the hearts and thoracic aortae of non-exercised rats. Co-administration of melatonin and HRT to exercised OVX rats reduced inflammatory response and upregulated SIRT1 expression in the aortic and cardiac tissues. The present study suggests that melatonin treatment, either alone or in combination with exercise and/or HRT, upregulates SIRT1 expression and alleviates oxidative injury and inflammation in the hearts and aortas of OVX rats. Melatonin should be considered in alleviating cardiovascular disease risk in postmenopausal women.

Effects of exogenous melatonin supplementation on health outcomes: An umbrella review of meta-analyses based on randomized controlled trials

Various melatonin supplementations have been developed to improve health outcomes in various clinical conditions. Thus, we sought to evaluate and summarize the effect of melatonin treatments in clinical settings for health outcomes. We searched PubMed/Medline, Embase, and Cochrane Library from inception to 4 February 2021. We included meta-analyses of randomized controlled trials investigating the melatonin intervention for any health outcome. Based on the different effect sizes of each meta-analysis, we calculated random models' standardized mean differences or risk ratios. We observed robust evidence supported by statistical significance with non-considerable heterogeneity between studies for sleep-related problems, cancer, surgical patients, and pregnant women. Patients with sleep disorder, sleep onset latency (SMD 0.33, 95% CI: 0.10 - 0.56, P < 0.01) were significantly improved whereas no clear evidence was shown with sleep efficiency (1.10, 95% CI: -0.26 to 2.45). The first analgesic requirement time (SMD 5.81, 95% CI: 2.57-9.05, P < 0.001) of surgical patients was distinctly improved. Female patients under artificial reproductive technologies had significant increase in the top-quality embryos (SMD 0.53, 95% CI: 0.27 - 0.79, P < 0.001), but no statistically clear evidence was found in the live birth rate (SMD 1.20, 95% CI: 0.83 - 1.72). Survival at one year (RR 1.90, 95% CI: 1.28 - 2.83, P < 0.005) significantly increased with cancer patients. Research on melatonin interventions to treat clinical symptoms and sleep problems among diverse health conditions was identified and provided considerable evidence. Future well-designed randomized clinical trials of high quality and subgroup quantitative analyses are essential.