Melatonin in sleep disorders

Exposure to artificial lighting at night: from an ecological challenge to a risk factor for glucose dysmetabolism and gestational diabetes? Narrative review

INTRODUCTION

Artificial lighting at night (ALAN) leads to pervasive light pollution, affecting ecosystems and human health globally. Satellite assessments reveal widespread nocturnal illumination worldwide and research indicates adverse health effects. Environmental light pollution disrupts natural cycles, affecting the behavior and reproduction of various organisms.

AIM/METHOD

In this narrative review we aimed to present research on the effects of ALAN on glucose metabolism and diabetes and hone on its recently reported association with gestational diabetes (GDM).

RESULTS

Conflicting data exist on the effects of melatonin's administration vis-à-vis glycemia, with some studies suggesting beneficial outcomes for patients with type 2 diabetes mellitus and insomnia. Ambient light influences plasma glucose, with bright light increasing both fasting and postprandial glucose levels. Perinatal light exposure is linked to later-life health risks and prenatal exposure to ALAN is linked to fetal macrosomia. Analyzing European ALAN data in conjunction with epidemiological records for GDM reveals a notable probable association. Additionally, recent research from China (one case-control and two cohort studies) has shown that exposure to ALAN during pregnancy significantly increases the risk of GDM.

DISCUSSION/CONCLUSION

Despite progress, interdisciplinary research is needed to understand the impact of light pollution on health, especially regarding disrupted light-dark cycles and physiological functions relevant to conditions like GDM. At present, the simplest advice for all people and particularly for women who anticipate pregnancy, or for pregnant women, is to ensure a totally dark environment during sleep time.

Efficacy of melatonin for treatment and prevention of neonatal necrotizing enterocolitis: a systematic review

The purpose of this study was to systematically review the available literature evaluating the use of melatonin for preventing and treating neonatal necrotizing enterocolitis (NEC). A systematic review of studies examining the effect of melatonin on neonatal NEC was conducted. The databases of Medline, Scopus, WOS, Embase, and Cochrane Central Register of Controlled Trials were searched for relevant studies. For risk of bias and applicability, The ROB2 tool was used for randomized controlled trials, and the ROBINS-I tool was used for non-randomized controlled trials. Three studies, comprising 106 preterm neonates, were included in the review, whose mean gestational ages ranged from 31.8 to 33.53 weeks. Melatonin doses varied among the studies. A randomized, double-blind, placebo-controlled study revealed that early administration of melatonin in preterm newborns resulted in a decrease in lipid peroxidation during the initial days of life. Two studies evaluated the role of melatonin in NEC. Both reported significant clinical and laboratory improvements in the melatonin groups, including reduced abdominal distension, metabolic acidosis, thrombocytopenia, hyponatremia, and lower mortality rates compared to control groups. This systematic review suggests that melatonin may be a potential therapeutic approach for NEC in preterm infants. However, further RCTS are needed to establish its therapeutic or preventive role.

Association between shift work and eating behaviours, sleep quality, and mental health among Italian workers

PURPOSE

Recent studies indicate that shift work may affect workers' eating habits and overall well-being. This study aimed to assess differences in eating patterns, sleep quality, and mental health between Italian shift and non-shift workers, with a focus on individual chronotype and the type of shift work (day vs. night shift).

METHODS

The cross-sectional study involved 322 subjects (166 shift and 156 non-shift workers). Eating habits were evaluated using a 7-day diary and the Medi-Lite questionnaire. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI), and mental health with the Depression Anxiety Stress Scales (DASS). Individual chronotype was defined using the Morningness-Eveningness Questionnaire.

RESULTS

No significant differences in daily energy, macronutrient, and micronutrient intake between the two groups, nor in the temporal pattern of eating. However, shift workers had significantly (p < 0.05) lower adherence to the Mediterranean diet (MD) (7.6 ± 2.3 vs 8.1 ± 2.2) compared to non-shift workers. Shift workers also reported significantly poorer sleep quality (mean PSQI score 7.6 ± 3.7 vs. 5.8 ± 3.0) and higher levels of anxiety and stress symptoms. Among shift workers, those with an evening chronotype had significantly lower MD adherence than those with a morning chronotypes. Additionally, night shift workers experienced more sleep disturbances compared to day ones.

CONCLUSION

Shift workers reported lower MD adherence, poorer sleep quality, and a higher prevalence of anxiety and stress symptoms compared to a similar group of non-shift workers. Evening chronotypes and night shift work were associated with worse eating habits and sleep quality.

Understanding the mechanistic interlink between circadian misalignment and heart disease in night shift workers: Therapeutic role of behavioral interventions

BACKGROUND

Rotating and night shift work, especially in older workers, is a growing health concern of modern societies due to the associated high morbidity and mortality rates from cardiovascular disease (CVD). The resulting circadian misalignment disrupts neuroendocrine pathways that regulate cardiovascular physiology, risking myocardial tissue damage and heart dysfunction.

AIMS

Considering the gaps in the literature as to how atypical work behaviors may disrupt the temporal link between the central and myocardial oscillators at the level of the proteome and transcriptome, the primary goal of this review is to assess the molecular mechanisms linking disrupted biological rhythms to heart health, with a focus on core clock genes like BMAL1 and cardiac troponin I (cTnI) as a myocardial biomarker.

MAJOR FINDINGS

Circadian misalignment can lead to cognitive decline, metabolic dysfunction, and immune disruption, all of which elevate CVD risk. BMAL1 has a key role in maintaining cardiovascular integrity, with its dysfunction associated with hypertension, arrhythmias, and myocardial injury. Additionally, disrupted sleep patterns influence the expression of clock genes, potentially leading to altered heart function and elevated levels of cardiac biomarkers like troponin.

CONCLUSION

Circadian misalignment poses significant CVD risks, particularly for older workers. Future research should investigate how the expression of central and peripheral clock genes, as well as cardiac biomarkers is affected by shift work, especially in older individuals. Behavioral interventions such as chronotherapy, light therapy, and scheduled evening sleep may help mitigate these risks, but more studies are needed to assess their long-term effectiveness.

Interaction between clock genes, melatonin and cardiovascular outcomes from ICU patients

BACKGROUND

Circadian rhythms, driven by biological clocks, help organisms align their physiological functions with environmental changes, promoting homeostasis. The central clock in the suprachiasmatic nucleus coordinates peripheral clocks via neurohumoral feedback involving proteins like CLOCK, BMAL1, CRY 1/2, and PER 1-3. In the ICU, these circadian processes often face disruptions from constant lighting, noise, and irregular sleep-wake cycles, impairing sleep quality and worsening stress responses. These disruptions can lead to adverse clinical effects, including higher cardiovascular complication rates. This study examines how ICU stays affect circadian rhythm regulators and their association with cardiovascular outcomes.

RESULTS

Significant differences were identified in melatonin levels and the expression of BMAL1, PER1, RORA, and NR1D1 between ICU stays of ≤7 days and >7 days. The APACHE-II severity scale influenced melatonin and the expression of CLOCK, PER2, CRY2, and RORA. Nonlinear relationships were observed between melatonin, clock genes, heart rate, and blood pressure (systolic and diastolic). In certain groups, molecular and physiological data showed correlations exceeding 90%.

CONCLUSIONS

These findings highlight a robust association between circadian disruption, as measured by melatonin and clock genes, and cardiovascular physiological rhythms in ICU patients.

Gene expression analysis of cytokines and MMPs in melatonin and rhBMP-2 enhanced bone remodeling

BACKGROUND

In the medical and dental fields, there is a need for studies of new therapeutic approaches for the treatment of bone defects that cause extensive bone loss. Melatonin may be an important endogenous biological factor for bone remodeling, and growth factors may enhance the repair process.

AIM

To evaluate the gene expression of cytokines (IL-1β, IL-6, IL-10 and TNF-α), markers of osteoclastogenesis (RANK, RANKL and OPG) and MMPs (MMP-1, MMP-2, MMP-8 and MMP-13) from the treatment of melatonin associated with an osteogenic membrane and rhBMP-2 on the recovery of a bone injury.

METHODS

Sixty-four rats were used and divided into 9 experimental groups and were formed according to the treatment carried out in the region of the bone lesion, which varied between the combination of 1, 10 and 100 μmol/L of melatonin. Gene Expression analysis was performed using real time-PCR by reading the concentration of total RNA and reverse transcription.

RESULTS

There were differences between groups when compared with clot or scaffold control, and improvement with a higher concentration of melatonin or rhBMP-2. The combination melatonin (1 µg) with 5 μg of rhBMP-2, using the guided bone regeneration technique, demonstrated some effects, albeit mild, on bone repair of critical bone defects.

CONCLUSION

This indicates that the approach for administering these substances needs to be reassessed, with the goal of ensuring their direct application to the affected area. Therefore, future research must be carried out, seeking to produce materials with these ideal characteristics.

Prevalence and Correlates of Poor Sleep Quality Among Psychiatry Physicians in Saudi Arabia: A Cross-Sectional Study

Background and Aims

Sleep issues pose a significant burden to public health and well-being in Saudi Arabia. However, research evidence on sleep health among psychiatry physicians in this territory is limited. Therefore, to bridge the research gap, this study was designed to assess the prevalence and predictors of poor sleep quality among psychiatry physicians in the country.

Methods

This cross-sectional study included 554 psychiatry physicians in Saudi Arabia from March to August 2023. Data were collected via online through a structured questionnaire (Google survey form). Sleep quality, the outcome variable of our study, was evaluated with the Pittsburgh Sleep Quality Index (PSQI; 19 items). Independent variables included sociodemographic and behavioral characteristics, sleep habits, major depression (assessed with Patient Health Questionnaire-9), and anxiety (measured with Generalized Anxiety Disorder-7) symptoms. Binary logistic regression analysis was performed to identify the correlates of poor sleep quality.

Results

Based on the PSQI, 61.3% of the study participants had poor-quality sleep (age range: 24-56 years, male: 48.0%). The adjusted model revealed that male participants (AOR = 2.80, 95% CI = 1.70-4.61) and those who had on-call duties ≥ 2 times per week (for three/four per week: AOR = 3.41, 95% CI = 1.89-6.14) were at higher risk of developing poor sleep quality compared to their respective counterparts. Participants with depressive symptoms (AOR = 3.46, 95% CI = 1.60-7.48) and smoking habits (AOR = 3.47, 95% CI = 1.32-9.08) had higher odds of developing poor sleep quality than their counterparts. Moreover, participants who always used their smartphone/laptop before going to bed were more likely to have poor sleep quality than those who never used such (AOR = 3.15, 95% CI = 1.31-7.60).

Conclusion

Poor sleep quality is extremely prominent among psychiatry physicians in Saudi Arabia. Male sex, higher on-call duty, smoking habits, depression, and smartphone/laptop use before bedtime were significantly associated with poor sleep quality. These findings emphasize the need for sleep-health promotion interventions for Saudi psychiatry physicians.

Pichia pastoris secreted peptides crossing the blood-brain barrier and DSIP fusion peptide efficacy in PCPA-induced insomnia mouse models

Background

Pichia pastoris-secreted delta sleep inducing peptide and crossing the blood-brain barrier peptides (DSIP-CBBBP) fusion peptides holds significant promise for its potential sleep-enhancing and neurotransmitter balancing effects. This study investigates these properties using a p-chlorophenylalanine (PCPA) -induced insomnia model in mice, an approach akin to traditional methods evaluating sleep-promoting activities in fusion peptides.

Aim of the study

The research aims to elucidate the sleep-promoting mechanism of DSIP-CBBBP, exploring its impact on neurotransmitter levels and sleep regulation, and to analyze its composition and structure.

Materials and methods

Using a PCPA-induced insomnia mouse model, the study evaluates the sleep-promoting effects of DSIP-CBBBP. The peptide's influence on neurotransmitters such as 5-HT, glutamate, dopamine, and melatonin is assessed. The functions of DSIP-CBBBP are characterized using biochemical and animal insomnia-induced behavior tests and compared without CBBBP.

Results

DSIP-CBBBP demonstrates a capacity to modulate neurotransmitter levels, indicated by changes in 5-HT, glutamate, DA, and melatonin. DSIP-CBBBP shows a better restorative effect than DSIP on neurotransmitter imbalance and the potential to enhance sleep.

Conclusion

The study underscores DSIP-CBBBP potential in correcting neurotransmitter dysregulation and promoting sleep, hinting at its utility in sleep-related therapies.

Comparative evaluation of salivary melatonin levels in patients with bruxism: a case-control study

Aim: To examine whether there is any difference in the levels of salivary melatonin between bruxism and nonbruxism groups and to compare the stress and anxiety levels between the two groups.Materials & methods: Patients meeting the probable bruxism criteria according to the International Consensus on the Assessment of Bruxism Criteria were included in the bruxism group. The salivary melatonin concentrations of both groups were measured using an ELISA kit. To determine the relationship between stress and bruxism, the State-Trait Anxiety Inventory (STAI) test was used.Results: The bruxism group had a significantly lower night-time salivary melatonin level than the control group (p < 0.05). No significant difference was determined between the bruxism group and the control group in respect of the STAI-T scores (p > 0.05).Conclusion: The study findings revealed a strong relationship between a low melatonin level and bruxism.

Synthesis of Novel Acrylamide Graft Copolymer of Acacia nilotica Gum for the Stabilization of Melatonin Nanoparticles for Improved Therapeutic Effect: Optimization Using (3)2 Factorial Design

The objective of the present study was to optimize the microwave-assisted synthesis of the acrylamide graft copolymer of Acacia nilotica gum (AM-co-ANG). Furthermore, graft copolymer was used for the formulation of a nanoparticulate system using a novel top to bottom solvent antisolvent technique for the delivery of melatonin. Grafting of ANG was optimized by using 32 factorial design, where concentrations of polymer and monomer (acrylamide) were used as independent variables and swelling index in acidic (0.1 N HCl) and basic (1 N NaOH) pH. Grafted polymers were further used to develop and optimize nanoparticulate system using concentration of the graft copolymer and concentration of drug as independent variables. The size of the nanoformulation and entrapment efficiency were selected as dependent variables. Difference in infrared spectrum and absorbance maxima in the ultraviolet region confirm that grafting has taken place. Porous structure and a higher contact angle confirmed hydrophobic nature of AM-co-ANG as compared with the native polymer. Acrylamide graft copolymers show more swelling in 1 N NaOH as compared with 0.1 N HCl. In vitro toxicity studies in hepatic (HepG2 cell line), brain (SHSY5Y cell line), and skin (HaCaT cell line) cells easily predict that synthesized polymer have no cytotoxicity. The entrapment efficiency ranged from 55.24 ± 1.35% to 73.21 ± 1.83%. A nonlinear correlation was observed between independent and dependent variables, as confirmed by multivariate analysis of variance, surface regression, and the correlation report. The prepared formulations were able to release drug up to 12 h. The regression coefficient easily predicted that most of the formulations followed Baker-Lonsdale drug release kinetics.

Effect of melatonin on insomnia and daytime sleepiness, in patients with obstructive sleep apnea and insomnia (COMISA): A randomized double-blinded placebo-controlled trial

BACKGROUND

COMISA is a common disorder that results in nighttime awakenings ,daytime sleepiness and PAP intolerance. Cognitive behavioral therapy for insomnia is used to improve PAP adherence and no medication has been evaluated in such population yet. Melatonin with its chronobiotic and antioxidant effects may have potential benefits on COMISA consequences at the appropriate dose and time. This study aimed to evaluate the effect of melatonin on sleep quality, daytime sleepiness and PAP Compliance in patients with COMISA.

METHODS

This double-blind placebo trial randomly assigned eligible OSA patients who suffered from insomnia despite using PAP for over a month to receive either melatonin 10 mg or placebo. The primary outcomes were measured by changes in the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), and Functional Outcomes of Sleep Questionnaire (FOSQ-10) over one month. Adherence to PAP was measured by the results of the PAP device reports on the average length of time and number of nights that the device was used.

RESULTS

Thirty patients were enrolled in the study after randomization. The melatonin arm showed significant improvement in all four primary outcomes compared to the placebo arm. The PSQI score was 3.836±1.839 in the melatonin arm versus 10.522±3.626 in the placebo arm (Pvalue<0.001). The ISI score was 8.476±3.568 in the melatonin arm versus 14.47±4.50 in the placebo arm (Pvalue<0.001). The ESS score was 6.854±4.334 in the melatonin arm versus 13.298±5.119 in the placebo arm (Pvalue<0.001). The FOSQ-10 score was 24.93±5.02 in the melatonin arm versus 19.87±4.24 in the placebo arm (Pvalue= 0.006). Additionally, nighttime consequences such as sleep latency and awakenings showed significant improvement in the melatonin arm. PAP devices results revealed improvement in duration of PAP use overnight.  CONCLUSIONS: Administering melatonin has been shown to improve self-reported sleep quality and PAP adherence in patients with COMISA.

TRIAL REGISTRATION

Registration number IRCT20220105053635N1 was issued by the Iranian Registry of Clinical Trials (IRCT).

Causal associations between modifiable risk factors and isolated REM sleep behavior disorder: a mendelian randomization study

Objectives

This Mendelian randomization (MR) study identified modifiable risk factors for isolated rapid eye movement sleep behavior disorder (iRBD).

Methods

Genome-wide association study (GWAS) datasets for 29 modifiable risk factors for iRBD in discovery and replication stages were used. GWAS data for iRBD cases were obtained from the International RBD Study Group. The inverse variance weighted (IVW) method was primarily employed to explore causality, with supplementary analyses used to verify the robustness of IVW findings. Co-localization analysis further substantiated causal associations identified via MR. Genetic correlations between mental illness and iRBD were identified using trait covariance, linkage disequilibrium score regression, and co-localization analyses.

Results

Our study revealed causal associations between sun exposure-related factors and iRBD. Utilizing sun protection (odds ratio [OR] = 0.31 [0.14, 0.69], p = 0.004), ease of sunburn (OR = 0.70 [0.57, 0.87], p = 0.001), childhood sunburn occasions (OR = 0.58 [0.39, 0.87], p = 0.008), and phototoxic dermatitis (OR = 0.78 [0.66, 0.92], p = 0.003) decreased iRBD risk. Conversely, a deep skin color increased risk (OR = 1.42 [1.04, 1.93], p = 0.026). Smoking, alcohol consumption, low education levels, and mental illness were not risk factors for iRBD. Anxiety disorders and iRBD were genetically correlated.

Conclusion

Our study does not corroborate previous findings that identified smoking, alcohol use, low education, and mental illness as risk factors for iRBD. Moreover, we found that excessive sun exposure elevates iRBD risk. These findings offer new insights for screening high-risk populations and devising preventive measures.

Therapeutic potential of melatonin in targeting molecular pathways of organ fibrosis

Fibrosis, the excessive deposition of fibrous connective tissue in an organ in response to injury, is a pathological condition affecting many individuals worldwide. Fibrosis causes the failure of tissue function and is largely irreversible as the disease progresses. Pharmacologic treatment options for organ fibrosis are limited, but studies suggest that antioxidants, particularly melatonin, can aid in preventing and controlling fibrotic damage to the organs. Melatonin, an indole nocturnally released from the pineal gland, is commonly used to regulate circadian and seasonal biological rhythms and is indicated for treating sleep disorders. While it is often effective in treating sleep disorders, melatonin's anti-inflammatory and antioxidant properties also make it a promising molecule for treating other disorders such as organ fibrosis. Melatonin ameliorates the necrotic and apoptotic changes that lead to fibrosis in various organs including the heart, liver, lung, and kidney. Moreover, melatonin reduces the infiltration of inflammatory cells during fibrosis development. This article outlines the protective effects of melatonin against fibrosis, including its safety and potential therapeutic effects. The goal of this article is to provide a summary of data accumulated to date and to encourage further experimentation with melatonin and increase its use as an anti-fibrotic agent in clinical settings.

The Impact of Sleep Disorders on Cardiovascular Health: Mechanisms and Interventions

This comprehensive review article explores the intricate mechanisms at work and possible remedies for the connection between sleep issues and cardiovascular health. Sleep disorders, which include conditions like insomnia and sleep apnea, are drawing increasing amounts of attention due to their serious detrimental consequences on cardiovascular health. This article carefully examines the body of existing evidence to explain the intricate mechanisms that connect sleep disruptions to cardiovascular issues. Mechanisms include inflammation, disruption of the autonomic nervous system, endothelial dysfunction, and aberrant metabolic processes all have an impact on these pathways. The study also looks at a variety of existing and novel therapeutic modalities that aim to minimize the detrimental effects of sleep disruptions on cardiovascular health. This includes evaluating the effectiveness of lifestyle changes, pharmaceutical interventions, and behavioural therapy for enhancing sleep quality and hence preserving cardiovascular health. By synthesising and presenting the most recent study data, this article offers valuable insights into the complex relationships between sleep patterns, cardiovascular function, and potential therapeutics. These results provide a solid foundation for guiding future research endeavours and clinical judgements. Pharmacotherapy is a possibility for momentary relief. Cardiovascular illness has been linked to the sensorimotor problem known as restless legs syndrome (RLS), which causes a strong impulse to move the legs. Sleep disruption caused by RLS-related leg movements leads to sympathetic activation, elevated blood pressure, impaired vascular function, and potential iron deficiency. Treating the underlying iron deficiency, when present, and medications targeting dopamine receptors or regulating calcium channels are the primary interventions for RLS. In conclusion, sleep disorders significantly impact cardiovascular health through multiple mechanisms. Early detection, accurate diagnosis, and appropriate interventions are crucial for mitigating associated cardiovascular risks. Multidisciplinary approaches including lifestyle modifications, behavioral interventions, and targeted pharmacotherapy have shown promise in improving sleep quality and cardiovascular outcomes. Further research is needed to enhance our understanding of the complex interplay between sleep disorders and cardiovascular health, leading to the development of more effective interventions and improved patient outcomes.

Acupuncture and moxibustion in patients with cancer-related insomnia: A systematic review and network meta-analysis

OBJECTIVES

Cancer-related insomnia (CRI) is one of the most common and serious symptoms in patients with cancer. Acupuncture and moxibustion have been widely applied in the treatment of CRI. Nevertheless, the comparative efficacy and safety of different acupuncture and moxibustion techniques remain unclear. This study aimed to evaluate and compare the efficacy and safety of different acupuncture and moxibustion techniques in the treatment of CRI.

METHODS

Eight medical databases were comprehensively searched for relevant randomized controlled trials (RCTs) as of June 2022. Two independent reviewers assessed the risk of bias and conducted the research selection, data extraction, and quality assessment of the included RCTs. A network meta-analysis (NMA) was performed using frequency models, combining all available direct and indirect evidence from RCTs. The Pittsburgh Sleep Quality Index (PSQI) was set as the primary outcome, and adverse events and effective rates were set as the secondary outcomes. The efficacy rate was calculated as the ratio of patients with insomnia symptom relief to the total number of patients.

RESULTS

Thirty-one RCTs with 3,046 participants were included, including 16 acupuncture- and moxibustion-related therapies. Transcutaneous electrical acupoint stimulation [surface under the cumulative ranking curve (SUCRA) 85.7%] and acupuncture and moxibustion (SUCRA 79.1%) were more effective than Western medicine, routine care, and placebo-sham acupuncture. Furthermore, Western medicine showed significantly better effects than placebo-sham acupuncture. In the NMA, the acupuncture and moxibustion treatments with the best therapeutic effects for CRI were transcutaneous electrical acupoint stimulation (SUCRA 85.7%), acupuncture and moxibustion (SUCRA 79.1%), auricular acupuncture (SUCRA 62.9%), routine care combined with intradermal needling (SUCRA 55.0%), and intradermal needling alone (SUCRA 53.3%). No serious acupuncture- or moxibustion-related adverse events were reported in the included studies.

CONCLUSION

Acupuncture and moxibustion are effective and relatively safe in treating CRI. The relatively conservative recommended order of acupuncture- and moxibustion-related therapies for CRI is as follows: transcutaneous electrical acupoint stimulation, acupuncture and moxibustion, and auricular acupuncture. However, the methodological quality of the included studies was generally poor, and further high-quality RCTs are needed to strengthen the evidence base.

Study of the Effects of Melatonin on Sleep Disorders in Pulmonary Sarcoidosis Patients

Background

The symptoms of pulmonary sarcoidosis may lead to fatigue, excessive daytime sleepiness, poor sleep quality, and a decrease in quality of life in these patients.

Objectives

This study was designed to evaluate the effects of oral melatonin on sleep disorders of patients with pulmonary sarcoidosis.

Methods

A randomized, single-blinded clinical trial was conducted on patients with pulmonary sarcoidosis. Eligible patients were randomly allocated into melatonin and control groups. Patients in the melatonin group were given 3 mg melatonin one hour before bedtime for three months. Sleep quality, daytime sleepiness, fatigue status, and quality of life were assessed applying General Sleep Disturbance Scale (GSDS), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Fatigue Assessment Scale (FAS), and the Patient-Reported Outcomes Measurement Information System (PROMIS), respectively, as well as the 12-item Short Form Survey (SF-12) scores at the baseline and three months after treatment.

Results

There was a significant change in the GSDS (P < 0.001), PSQI (P < 0.001), ESS (P = 0.002), and FAS (P < 0.001) scores, which were decreased, compared to those of the control group. After intervention¸ global physical health and global mental health raw scores were improved comparing to the control group (P = 0.006, P = 0.02, respectively). The 12-item Short Form Survey evaluation showed that there was a significant difference between the melatonin (3.38 ± 4.61) and control (0.55 ± 7.25) groups in PCS-12 score after three months of therapy (P = 0.02).

Conclusions

Our findings showed that supplemental melatonin could significantly improve sleep problems, quality of life, and excessive daytime sleepiness in sarcoidosis patients.

Efficacy on sleep parameters and tolerability of melatonin in individuals with sleep or mental disorders: A systematic review and meta-analysis

We conducted the first systematic review and series of meta-analyses to assess the efficacy and tolerability of melatonin in children/adolescents or adults with sleep or mental health disorders, using the same set of criteria across disorders and ages. Based on a pre-registered protocol (PROPSPERO: CRD42021289827), we searched a broad range of electronic databases up to 02.02.2021 for randomized control trials (RCTs) of melatonin. We assessed study quality using the Risk of Bias tool, v2. We included a total of 34 RCTs (21 in children/adolescents: N = 984; 13 in adults: N = 1014). We found evidence that melatonin significantly improved sleep onset latency and total sleep time, but not sleep awaking, in children and adolescents with a variety of neurodevelopmental disorders, and sleep onset latency (measured by diary) as well as total sleep time (measured with polysomnography) in adults with delayed sleep phase disorder. No evidence of significant differences between melatonin and placebo was found in terms of tolerability. We discuss clinical and research implications of our findings.

Metabolic Anti-Cancer Effects of Melatonin: Clinically Relevant Prospects

Metabolic reprogramming characterized by alterations in nutrient uptake and critical molecular pathways associated with cancer cell metabolism represents a fundamental process of malignant transformation. Melatonin (N-acetyl-5-methoxytryptamine) is a hormone secreted by the pineal gland. Melatonin primarily regulates circadian rhythms but also exerts anti-inflammatory, anti-depressant, antioxidant and anti-tumor activities. Concerning cancer metabolism, melatonin displays significant anticancer effects via the regulation of key components of aerobic glycolysis, gluconeogenesis, the pentose phosphate pathway (PPP) and lipid metabolism. Melatonin treatment affects glucose transporter (GLUT) expression, glucose-6-phosphate dehydrogenase (G6PDH) activity, lactate production and other metabolic contributors. Moreover, melatonin modulates critical players in cancer development, such as HIF-1 and p53. Taken together, melatonin has notable anti-cancer effects at malignancy initiation, progression and metastasing. Further investigations of melatonin impacts relevant for cancer metabolism are expected to create innovative approaches supportive for the effective prevention and targeted therapy of cancers.