A Polymorphism Cluster at the 2q12 locus May Predict Response to Piromelatine in Patients with Mild Alzheimer's Disease

BACKGROUND

Piromelatine is a novel melatonin MT1/2/3 and serotonin 5-HT-1A/1D receptors agonist developed for mild Alzheimer's disease (AD). In a randomized, placebo-controlled, dose-ranging study (ReCognition) of piromelatine (5, 20, and 50 mg daily for 6 months) in participants with mild dementia due to AD (n=371, age 60-85 years), no statistically significant differences were found between the piromelatine and placebo-treated groups on the primary (i.e., computerized neuropsychological test battery (cNTB)) and secondary outcomes (ADCS-CGIC, ADCS-MCI-ADL, ADAS-cog14, NPI, and Pittsburgh Sleep Quality Index (PSQI)) nor were there safety concerns (https://clinicaltrials.gov/ct2/show/NCT02615002).

OBJECTIVES

This study was aimed at identifying genetic markers predicting piromelatine treatment response using a genome-wide association approach (GWAS).

DESIGN

Variant genotyping of a combined whole genome and whole exome sequencing was performed using DNA extracted from lymphocytes from consenting participants. The general case-control allelic test was performed on piromelatine-treated participants, taking "responders" (i.e., >0.125 change from baseline in the cNTB) as cases and "non responders" as controls, using a Cochran-Armitage trend test.

SETTING

58 outpatient clinics in the US.

PARTICIPANTS

371 participants were randomized in the trial; 107 provided informed consent for genotyping.

RESULTS

The GWAS sample did not differ from the full study cohort in demographics, baseline characteristics, or response to piromelatine. Six single-nucleotide polymorphisms (SNPs) in chromosome 2q12 (2:107,510,000-107,540,000) were associated with response (p-value < 1x10 -4 each). Post hoc analyses suggested that the carriers of the 2q12 polymorphism cluster (27% of the GWAS sample) improved significantly on the cNTB on piromelatine as compared to placebo but significantly worsened on the ADAS-Cog14 and PSQI. By contrast, "non-carriers" improved significantly with piromelatine compared to placebo on the ADAS-Cog14 ( 2.91 (N=23) with piromelatine 20 mg vs 1.65 (N=19) with placebo (p=0.03)) and PSQI.

CONCLUSIONS

The 2q12 (2:107,510,000-107,540,000) 5-6 SNPs cluster may predict efficacy of piromelatine for mild AD. These findings warrant further investigation in a larger, prospective early-stage AD clinical trial for patients who are non-carriers of the 2q12 polymorphism cluster.

Chronic Piromelatine Treatment Alleviates Anxiety, Depressive Responses and Abnormal Hypothalamic-Pituitary-Adrenal Axis Activity in Prenatally Stressed Male and Female Rats

The prenatal stress (PNS) model in rodents can induce different abnormal responses that replicate the pathophysiology of depression. We applied this model to evaluate the efficacy of piromelatine (Pir), a novel melatonin analog developed for the treatment of insomnia, in male and female offspring. Adult PNS rats from both sexes showed comparable disturbance associated with high levels of anxiety and depressive responses. Both males and females with PNS demonstrated impaired feedback inhibition of the hypothalamic-pituitary-adrenal (HPA) axis compared to the intact offspring and increased glucocorticoid receptors in the hippocampus. However, opposite to female offspring, the male PNS rats showed an increased expression of mineralocorticoid receptors in the hippocampus. Piromelatine (20 mg/kg, i.p., for 21 days injected from postnatal day 60) attenuated the high anxiety level tested in the open field, elevated plus-maze and light-dark test, and depressive-like behavior in the sucrose preference and the forced swimming tests in a sex-specific manner. The drug reversed to control level stress-induced increase of plasma corticosterone 120 min later in both sexes. Piromelatine also corrected to control level the PNS-induced alterations of corticosteroid receptors only in male offspring. Our findings suggest that the piromelatine treatment exerts beneficial effects on impaired behavioral responses and dysregulated HPA axis in both sexes, while it corrects the PNS-induced changes in the hippocampal corticosteroid receptors only in male offspring.

Melatonin, but not melatonin receptor agonists Neu-P11 and Neu-P67, attenuates TNBS-induced colitis in mice

Melatonin is known as a strong antioxidant and possesses anti-inflammatory properties. Recently, melatonin was shown to improve colitis in animal models of inflammatory bowel diseases. The aim of the present study was to characterize the role of melatonin receptors (MT) in the anti-inflammatory effect of melatonin and to assess the anti-inflammatory potential of two novel MT receptor agonists, Neu-P11 and Neu-P67, in the mouse model of trinitrobenzenesulfonic acid (TNBS)-induced colitis. Colitis was induced on day 1 by intracolonic (i.c.) administration of TNBS in 30 % ethanol in saline. Melatonin (4 mg/kg, per os (p.o.)), Neu-P11 (20 mg/kg, p.o.; 50 mg/kg, intraperitoneally (i.p.), 50 mg/kg, i.c.), and Neu-P67 (20 mg/kg, p.o.) were given twice daily for 3 days. Luzindole (5 mg/kg, i.p.) was injected 15 min prior to melatonin administration. On day 4, macroscopic and microscopic damage scores were assessed and myeloperoxidase (MPO) activity quantified using O-dianisidine-based assay. Melatonin significantly attenuated colitis in mice, as indicated by the macroscopic score (1.90 ± 0.34 vs. 3.82 ± 0.62 for melatonin- and TNBS-treated mice, respectively), ulcer score (0.87 ± 0.18 vs. 1.31 ± 0.19, respectively), and MPO activity (4.68 ± 0.70 vs.6.26 ± 0.94, respectively). Luzindole, a MT receptor antagonist, did not inhibit the anti-inflammatory effect of melatonin (macroscopic score 1.12 ± 0.22, ulcer score 0.50 ± 0.16); however, luzindole increased MPO activity (7.57 ± 1.05). MT receptor agonists Neu-P11 and Neu-P67 did not improve inflammation induced by TNBS. Melatonin, but not MT receptor agonists, exerts potent anti-inflammatory action in acute TNBS-induced colitis. Our data suggests that melatonin attenuates colitis by additional, MT receptor-independent pathways.

Neuroprotective mechanism of the novel melatonin derivative Neu-P11 in brain ischemia related models

Stopping the ischemic cascade by targeting its components is a potential strategy for acute ischemic stroke treatment. During ischemia and especially over reperfusion, oxidative stress plays a major role in causing neuronal cell death. Melatonin has been previously reported to provide neuroprotective effects in in vivo models of stroke by a mechanism that implicates melatonin receptors. In this context, this study was planned to test the potential neuroprotective effects of the novel melatonin MT1/MT2 receptor agonist, Neu-P11, against brain ischemia in in vitro and in vivo models, and to elucidate its underlying mechanism of action. Neu-P11 proved to be a good antioxidant, to protect against glutamate-induced excitotoxicity and oxygen and glucose deprivation in hippocampal slices, and to reduce infarct volume in an in vivo stroke model. Regarding its mechanism of action, the protective effect of Neu-P11 was reverted by luzindole (melatonin receptor antagonist), AG490 (JAK2 inhibitor), LY294002 (PI3/AKT inhibitor) and PD98059 (MEK/ERK1/2 inhibitor). In conclusion, Neu-P11 affords neuroprotection against brain ischemia in in vitro and in vivo models by activating a pro-survival signaling pathway that involves melatonin receptors, JAK/STAT, PI3K/Akt and MEK/ERK1/2.

Piromelatine exerts antinociceptive effect via melatonin, opioid, and 5HT1A receptors and hypnotic effect via melatonin receptors in a mouse model of neuropathic pain

RATIONALE

An effective and safe treatment of insomnia in patients with neuropathic pain remains an unmet need. Melatonin and its analogs have been shown to have both analgesic and hypnotic effects; however, capacity of them on sleep disturbance with neuropathic pain as well as the precise mechanism is unclear.

OBJECTIVE

The present study evaluated effects of piromelatine, a novel melatonin receptor agonist, on sleep disturbance in a neuropathic pain-like condition as well as the underlying mechanisms.

METHODS

A mouse model of chronic neuropathic pain induced by partial sciatic nerve ligation (PSL) was employed. The antinociceptive and hypnotic effects of piromelatine were evaluated by measurement of thermal hyperalgesia, mechanical allodynia, and electroencephalogram (EEG) recordings in PSL mice. Pharmacological approaches were used to clarify the mechanisms of action of piromelatine.

RESULTS

PSL significantly lowered thermal and mechanical latencies and decreased non-rapid eye movement (NREM) sleep, and PSL mice exhibited sleep fragmentation. Treatment with 25, 50, or 100 mg/kg of piromelatine significantly prolonged thermal and mechanical latencies and increased NREM sleep. Moreover, the antinociceptive effect of piromelatine was prevented by melatonin antagonist luzindole, opioid receptor antagonist naloxone, or 5HT1A receptor antagonist WAY-100635. The hypnotic effect of piromelatine was blocked by luzindole but neither by naloxone nor WAY-100635.

CONCLUSIONS

These data indicate that piromelatine is an effective treatment for both neuropathic pain and sleep disturbance in PSL mice. The antinociceptive effect of piromelatine is likely mediated by melatonin, opioid, and 5HT1A receptors; however, the hypnotic effect of piromelatine appears to be mediated by melatonin receptors.

Therapeutic effects of melatonin receptor agonists on sleep and comorbid disorders

Several melatonin receptors agonists (ramelteon, prolonged-release melatonin, agomelatine and tasimelteon) have recently become available for the treatment of insomnia, depression and circadian rhythms sleep-wake disorders. The efficacy and safety profiles of these compounds in the treatment of the indicated disorders are reviewed. Accumulating evidence indicates that sleep-wake disorders and co-existing medical conditions are mutually exacerbating. This understanding has now been incorporated into the new Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5). Therefore, when evaluating the risk/benefit ratio of sleep drugs, it is pertinent to also evaluate their effects on wake and comorbid condition. Beneficial effects of melatonin receptor agonists on comorbid neurological, psychiatric, cardiovascular and metabolic symptomatology beyond sleep regulation are also described. The review underlines the beneficial value of enhancing physiological sleep in comorbid conditions.

Melatonin receptors in diabetes: a potential new therapeutical target?

Melatonin is synthesized and secreted mainly by the pineal gland in a circadian fashion, and it thus mediates endogenous circadian rhythms and influences other physiological functions. Both the G-protein coupled receptors MT1 (encoded by MTNR1A) and MT2 (encoded by MTNR1B) in mammals mediate the actions of melatonin. Evidence from in vivo and in vitro studies proved a key role of melatonin in the regulation of glucose metabolism and the pathogenesis of diabetes, as further confirmed by the recent studies of human genetic variants of MTNR1B. Remarkably, it was also suggested that genetic variations within MTNR1B disordered β-cells function directly, i.e. insulin secretion. This indicated the functional link between MT2 and T2D risk at the protein level, and it may represent the prevailing pathomechanism for how impaired melatonin signaling causes metabolic disorders and increases the T2D risk. It is speculated that melatonin and its receptors may be a new therapeutic avenue in diabetes.

Add-on prolonged-release melatonin for cognitive function and sleep in mild to moderate Alzheimer's disease: a 6-month, randomized, placebo-controlled, multicenter trial

Purpose

A link between poor sleep quality and Alzheimer’s disease (AD) has recently been suggested. Since endogenous melatonin levels are already reduced at preclinical AD stages, it is important to ask whether replenishing the missing hormone would be beneficial in AD and whether any such effects would be related to the presence of sleep disorder in patients.

Patients and methods

The effects of add-on prolonged-release melatonin (PRM) (2 mg) to standard therapy on cognitive functioning and sleep were investigated in 80 patients (men [50.7%], women [49.3%], average age 75.3 years [range, 52–85 years]) diagnosed with mild to moderate AD, with and without insomnia comorbidity, and receiving standard therapy (acetylcholinesterase inhibitors with or without memantine). In this randomized, double-blind, parallel-group study, patients were treated for 2 weeks with placebo and then randomized (1:1) to receive 2 mg of PRM or placebo nightly for 24 weeks, followed by 2 weeks placebo. The AD Assessment Scale–Cognition (ADAS-Cog), Instrumental Activities of Daily Living (IADL), Mini–Mental State Examination (MMSE), sleep, as assessed by the Pittsburgh Sleep Quality Index (PSQI) and a daily sleep diary, and safety parameters were measured.

Results

Patients treated with PRM (24 weeks) had significantly better cognitive performance than those treated with placebo, as measured by the IADL (P=0.004) and MMSE (P=0.044). Mean ADAS-Cog did not differ between the groups. Sleep efficiency, as measured by the PSQI, component 4, was also better with PRM (P=0.017). In the comorbid insomnia (PSQI ≥6) subgroup, PRM treatment resulted in significant and clinically meaningful effects versus the placebo, in mean IADL (P=0.032), MMSE score (+1.5 versus −3 points) (P=0.0177), and sleep efficiency (P=0.04). Median ADAS-Cog values (−3.5 versus +3 points) (P=0.045) were significantly better with PRM. Differences were more significant at longer treatment duration. PRM was well tolerated, with an adverse event profile similar to that of placebo.

Conclusion

Add-on PRM has positive effects on cognitive functioning and sleep maintenance in AD patients compared with placebo, particularly in those with insomnia comorbidity. The results suggest a possible causal link between poor sleep and cognitive decline.

Melatonin rescues 3T3-L1 adipocytes from FFA-induced insulin resistance by inhibiting phosphorylation of IRS-1 on Ser307

Melatonin is biosynthesized in the pineal gland and secreted into the bloodstream. Evidences indicate a role of melatonin in the regulation of glucose metabolism. The objective of this study was to investigate the effect of melatonin on insulin sensitivity in insulin resistant adipocytes. Following a preincubation with melatonin or vehicle for 30 min, insulin resistant cells of 3T3-L1 adipocytes were induced by palmitic acids (300 μM, 6 h). Our results showed that palmitic acids inhibited both the basal and insulin-stimulated uptake of [(3)H]-2-Deoxyglucose, down-regulated the levels of IRS-1 and GLUT-4. However, compared to the vehicle group, melatonin pre-treatment increased significantly the uptake of [(3)H]-2-Deoxyglucose as well as the level of GLUT-4, and decreased phosphorylated IRS-1 (Ser307) although total IRS-1 did not change significantly. These data suggest that palmitic acids impair insulin signal via down-regulating the expressions of IRS-1 and GLUT-4; whereas melatonin can ameliorate insulin sensitivity by inhibiting Ser307 phosphorylation in IRS-1 and increasing GLUT-4 expressions in insulin resistant 3T3-L1 adipocytes. We conclude that melatonin regulates the insulin sensitivity and glucose homeostasis via inhibiting Ser-phosphorylation and improving function of IRS-1.

Antinociceptive effects of novel melatonin receptor agonists in mouse models of abdominal pain

AIM: To characterize the antinociceptive action of the novel melatonin receptor (MT) agonists, Neu-P11 and Neu-P12 in animal models of visceral pain.

METHODS: Visceral pain was induced by intracolonic (ic) application of mustard oil or capsaicin solution or by intraperitoneal (ip) administration of acetic acid. Neu-P11, Neu-P12, or melatonin were given ip or orally and their effects on pain-induced behavioral responses were evaluated. To identify the receptors involved, the non-selective MT1/MT2 receptor antagonist luzindole, the MT2 receptor antagonist 4-P-PDOT, or the μ-opioid receptor antagonist naloxone were injected ip or intracerebroventricularly (icv) prior to the induction of pain.

RESULTS: Orally and ip administered melatonin, Neu-P11, and Neu-P12 reduced pain responses in a dose-dependent manner. Neu-P12 was more effective and displayed longer duration of action compared to melatonin. The antinociceptive effects of Neu-P11 or Neu-P12 were antagonized by ip or icv. administered naloxone. Intracerebroventricularly, but not ip administration of luzindole or 4-P-PDOT blocked the antinociceptive actions of Neu-P11 or Neu-P12.

CONCLUSION: Neu-P12 produced the most potent and long-lasting antinociceptive effect. Further development of Neu-P12 for future treatment of abdominal pain seems promising.

Blood pressure reducing effects of piromelatine and melatonin in spontaneously hypertensive rats

BACKGROUND

Recently, widespread interest has grown regarding melatonin treatment of hypertension including its cardioprotective effects. Studies in rodents indicate that melatonin plays a role in the pathogenesis of hypertension in rats with metabolic syndrome. Piromelatine, a melatonin agonist, serotonin 5-HT-1A and 5-HT-1D agonist and serotonin 5-HT2B antagonist is a multimodal agent with sleep promoting, anti-diabetic, analgesic, anti-neurodegenerative, anxiolytic and antidepressant potential, currently in development for the treatment of insomnia.

AIM

In this report we assessed the effects of piromelatine and melatonin treatment on blood pressure in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats.

MATERIALS AND METHODS

Five groups of 12-wk-old rats (10/group) were treated for 5 weeks with a vehicle, piromelatine (5, 15 and 50 mg/kg BW) and melatonin (10 mg/kg BW) and an age-matched WKY control group. Systolic blood pressure (tail-cuff method) was measured weekly at 9:00 a.m. and at 9:00 p.m. The rats body weight, plasma glucose, insulin, triglyceride, adiponectin, total cholesterol, HDL and LDL/VLDL cholesterol were also measured.

RESULTS

Our results showed that both piromelatine and melatonin reduced SHR blood pressure significantly both during the morning and the evening. Piromelatine, but not melatonin, also reduced SHR body weight gain and both significantly decreased plasma glucose and insulin levels and increased adiponectin levels.

CONCLUSIONS

Piromelatine, similar to melatonin, has an antihypertensive effect and also attenuates body weight, improves metabolic profiles and might be useful in the treatment of hypertension and the metabolic syndrome.

A novel melatonin agonist Neu-P11 facilitates memory performance and improves cognitive impairment in a rat model of Alzheimer' disease

Previous studies have shown that melatonin is implicated in modulating learning and memory processing. Melatonin also exerts neuroprotective activities against Aβ-induced injury in vitro and in vivo. Neu-P11 (piromelatine, N-(2-(5-methoxy-1H-indol-3-yl)ethyl)-4-oxo-4H-pyran-2-carboxamide) is a novel melatonin (MT1/MT2) receptor agonist and a serotonin 5-HT1A/1D receptor agonist recently developed for the treatment of insomnia. In the present study we firstly investigated whether Neu-P11 and melatonin enhance memory performance in the novel object recognition (NOR) task in rats, and then assessed whether Neu-P11 and melatonin improve neuronal and cognitive impairment in a rat model of Alzheimer' disease (AD) induced by intrahippocampal Aβ(1-42) injection. The results showed that a single morning or afternoon administration of Neu-P11 enhanced object recognition memory measured at 4 or 24h after training. Melatonin was effective in the memory facilitating effects only when administered in the afternoon. Further results showed that intrahippocampal Aβ(1-42) injection resulted in hippocampal cellular loss, as well as decreased learning ability and memory in the Y maze and NOR tasks in rats. Neu-P11 but not melatonin attenuated cellular loss and cognitive impairment in the rat AD model. The current data suggest that Neu-P11 may serve as a novel agent for the treatment of AD.

Neu-164 and Neu-107, two novel antioxidant and anti-myeloperoxidase compounds, inhibit acute cigarette smoke-induced lung inflammation

Cigarette smoke is a profound proinflammatory stimulus that causes acute lung inflammation and chronic lung disease, including chronic obstructive pulmonary disease (COPD, emphysema, and chronic bronchitis), via a variety of mechanisms, including oxidative stress. Cigarette smoke contains high levels of free radicals, whereas inflammatory cells, including macrophages and neutrophils, express enzymes, including NADPH oxidase, nitric oxide synthase, and myeloperoxidase, that generate reactive oxygen species in situ and contribute to inflammation and tissue damage. Neu-164 and Neu-107 are small-molecule inhibitors of myeloperoxidase, as well as potent antioxidants. We hypothesized that Neu-164 and Neu-107 would inhibit acute cigarette smoke-induced inflammation. Adult C57BL/6J mice were exposed to mainstream cigarette smoke for 3 days to induce acute inflammation and were treated daily by inhalation with Neu-164, Neu-107, or dexamethasone as a control. Inflammatory cells and cytokines were assessed by bronchoalveolar lavage and histology. mRNA levels of endogenous antioxidant genes heme oxygenase-1 and glutamate-cysteine ligase modifier subunit were determined by qPCR. Cigarette smoke exposure induced acute lung inflammation with accumulation of neutrophils and upregulation of proinflammatory cytokines, including IL-6, macrophage inflammatory protein-2, and keratinocyte-derived cytokine. Both Neu-164 and Neu-107 significantly reduced the accumulation of inflammatory cells and the expression of inflammatory cytokines as effectively as dexamethasone. Upregulation of endogenous antioxidant genes was dampened. Neu-164 and Neu-107 inhibit acute cigarette smoke-induced inflammation by scavenging reactive oxygen species in cigarette smoke and by inhibiting further oxidative stress caused by inflammatory cells. These compounds may have promise in preventing or treating lung disease associated with chronic smoke exposure, including COPD.

Cardiovascular effects of melatonin receptor agonists

INTRODUCTION

Melatonin synchronizes circadian rhythms with light/dark period and it was demonstrated to correct chronodisruption. Several melatonin receptor agonists with improved pharmacokinetics or increased receptor affinity are being developed, three of them are already in clinical use. However, the actions of melatonin extend beyond chronobiology to cardiovascular and metabolic systems as well. Given the high prevalence of cardiovascular disease and their common occurrence with chronodisruption, it is of utmost importance to classify the cardiometabolic effects of the newly approved and putative melatoninergic drugs.

AREAS COVERED

In the present review, the available (although very sparse) data on such effects, in particular by the approved (circadin, ramelteon, agomelatine) or clinically advanced (tasimelteon, piromelatine = Neu-P11, TIK-301) compounds are summarized. The authors have searched for an association with blood pressure, vascular reactivity, ischemia, myocardial and vascular remodeling and metabolic syndrome.

EXPERT OPINION

The data suggest that cardiovascular effects of melatonin are at least partly mediated via MT(1)/MT(2) receptors and associated with its chronobiotic action. Therefore, despite the sparse direct evidence, it is believed that these effects will be shared by melatonin analogs as well. With the expected approval of novel melatoninergic compounds, it is suggested that the investigation of their cardiovascular effects should no longer be neglected.

Effect of melatonin on nocturnal blood pressure: meta-analysis of randomized controlled trials

Background

Patients with nocturnal hypertension are at higher risk for cardiovascular complications such as myocardial infarction and cerebrovascular insult. Published studies inconsistently reported decreases in nocturnal blood pressure with melatonin.

Methods

A meta-analysis of the efficacy and safety of exogenous melatonin in ameliorating nocturnal blood pressure was performed using a random effects model of all studies fitting the inclusion criteria, with subgroup analysis of fast-release versus controlled-release preparations.

Results

Seven trials (three of controlled-release and four of fast-release melatonin) with 221 participants were included. Meta-analysis of all seven studies did not reveal significant effects of melatonin versus placebo on nocturnal blood pressure. However, subgroup analysis revealed that controlled-release melatonin significantly reduced nocturnal blood pressure whereas fast-release melatonin had no effect. Systolic blood pressure decreased significantly with controlled-release melatonin (−6.1 mmHg; 95% confidence interval [CI] −10.7 to −1.5; P = 0.009) but not fast-release melatonin (−0.3 mmHg; 95% CI −5.9 to 5.30; P = 0.92). Diastolic blood pressure also decreased significantly with controlled-release melatonin (−3.5 mmHg; 95% CI −6.1 to −0.9; P = 0.009) but not fast-release melatonin (−0.2 mmHg; 95% CI −3.8 to 3.3; P = 0.89). No safety concerns were raised.

Conclusion

Add-on controlled-release melatonin to antihypertensive therapy is effective and safe in ameliorating nocturnal hypertension, whereas fast-release melatonin is ineffective. It is necessary that larger trials of longer duration be conducted in order to determine the long-term beneficial effects of controlled-release melatonin in patients with nocturnal hypertension.

Prolonged-release melatonin for insomnia - an open-label long-term study of efficacy, safety, and withdrawal

Background

Prolonged-release melatonin (PRM) 2 mg is indicated for insomnia in patients aged 55 years and older. A recent double-blind placebo-controlled study demonstrated 6-month efficacy and safety of PRM in insomnia patients aged 18–80 and lack of withdrawal and rebound symptoms upon discontinuation.

Objective

To investigate the efficacy, safety, and withdrawal phenomena associated with 6–12 months PRM treatment.

Methods

Data from a prospective 6–12-month open-label study of 244 community dwelling adults with primary insomnia, who had participated in a placebo-controlled, double-blind dose-ranging trial of PRM. Patients received PRM nightly, followed by a 2-week withdrawal period. Main outcome measures were patient-reported sleep quality ratings (diary), adverse events, vital signs, and laboratory tests recorded at each visit, and withdrawal symptoms (CHESS-84 [Check-list Evaluation of Somatic Symptoms]). Nocturnal urinary 6-sulfatoxymelatonin excretion, a measure of the endogenous melatonin production, was assessed upon discontinuing long-term PRM.

Results

Of the 244 patients, 36 dropped out, 112 completed 6 months of treatment, and the other 96 completed 12 months of treatment. The mean number of nights by which patients reported sleep quality as “good” or “very good” was significantly higher during PRM than before treatment. There was no evidence of tolerance to PRM. Discontinuation of PRM was not associated with rebound insomnia or withdrawal symptoms; on the contrary, residual benefit was observed. PRM was well tolerated, and there was no suppression of endogenous melatonin production.

Conclusion

Results support the efficacy and safety of PRM in primary insomnia patients aged 20–80 throughout 6–12 months of continuous therapy. PRM discontinuation even after 12 months was not associated with adverse events, withdrawal symptoms, or suppression of endogenous melatonin production.

Prolonged-release melatonin for children with neurodevelopmental disorders

Previous studies demonstrated the efficacy and safety of prolonged-release melatonin in children and adolescents with neurodevelopmental and behavioral disorders. The long-term effectiveness and safety of prolonged-release melatonin treatment were assessed in 88 children (42 girls and 46 boys) with neurodevelopmental disorders. These patients participated in a compassionate-use program with the drug Circadin (2 mg; Neurim Pharmaceuticals, Tel Aviv, Israel) in France, and received treatment in the context of regular care by a specialized physician. The study involved a structured questionnaire for the parents, comprising a combination of multiple-choice and numeric questions addressing sleep onset/offset, sleep quality problems, and mood. The dose of melatonin ranged from 4-6 mg, and treatment duration ranged from 6-72 months. Within 3 months, sleep latency with prolonged-release melatonin decreased by 44.0% (P < 0.001), sleep duration increased by 10.1% (P < 0.001), the number of awakenings decreased by 75% (P < 0.001), and sleep quality improved by 75%, compared with baseline (P < 0.001). No serious adverse events or treatment-related comorbidities were reported. Prolonged-release melatonin remains a safe, effective therapy for the long-term treatment of sleep disorders in children with neurodevelopmental disorders.

Prolonged release melatonin in the treatment of primary insomnia: evaluation of the age cut-off for short- and long-term response

OBJECTIVES

The authors recently reported on efficacy and safety of prolonged-release melatonin formulation (PRM; Circadin 2  mg) in elderly insomnia patients. The age cut-off for response to PRM and the long-term maintenance of efficacy and safety were further evaluated by looking at the total cohort (age 18-80 years) from that study and subsets of patients aged 18-54 and 55-80 years (for whom the drug is currently indicated).

DESIGN

Randomised, double-blind, placebo controlled trial.

SETTING

Multicentre, outpatients, primary care setting.

METHODS

A total of 930 males and females aged 18-80 years with primary insomnia who reported mean nightly sleep latency (SL) >20  min were enrolled and 791 entered the active phase of the study. The study comprised a 2-week, single-blind placebo run-in period followed by 3 week's double-blind treatment with PRM or placebo, one tablet per day at 2 hours before bedtime. PRM patients continued whereas placebo completers were re-randomised 1:1 to PRM or placebo for 26 weeks followed by 2-weeks run-out on placebo.

MAIN OUTCOME MEASURES

SL and other sleep variables derived from sleep diary, Pittsburgh Sleep Quality Index (PSQI), Quality of life (WHO-5), Clinical Global Impression of Improvement (CGI-I) and adverse effects, recorded each visit, withdrawal and rebound effects during run-out.

RESULTS

In all, 746 patients completed the 3-week and 555 (421 PRM, 134 placebo) completed the 6-month period. The principal reason for drop-out was patient decision. At 3 weeks, significant differences in SL (diary, primary variable) in favour of PRM vs. placebo treatment were found for the 55-80-year group (-15.4 vs. -5.5  min, p = 0.014) but not the 18-80-year cut-off which included younger patients. Other variables (SL-PSQI, PSQI, WHO-5, CGI-I scores) improved significantly with PRM in the 18-80-year population, more so than in the 55-80-year age group. Improvements were maintained or enhanced over the 6-month period with no signs of tolerance. No withdrawal symptoms or rebound insomnia were detected. Most adverse events were mild with no significant differences between PRM and placebo groups in any safety outcome.

CONCLUSIONS

The results demonstrate short- and long-term efficacy of PRM in insomnia patients aged 18-80 years, particularly those aged 55 and over. PRM was well-tolerated over the entire 6-month period with no rebound or withdrawal symptoms following discontinuation. Study Registry No: ClinicalTrials.gov ID: NCT00397189.

Efficacy and safety of prolonged-release melatonin in insomnia patients with diabetes: a randomized, double-blind, crossover study

BACKGROUND

Diabetes is a major comorbidity in insomnia patients. The efficacy and safety of prolonged-release melatonin 2 mg in the treatment of glucose, lipid metabolism, and sleep was studied in 36 type 2 diabetic patients with insomnia (11 men, 25 women, age 46-77 years).

METHODS

In a randomized, double-blind, crossover study, the subjects were treated for 3 weeks (period 1) with prolonged-release melatonin or placebo, followed by a one-week washout period, and then crossed over for another 3 weeks (period 2) of treatment with the other preparation. All tablets were taken 2 hours before bedtime for a period of 3 weeks. In an extension period of 5 months, prolonged-release melatonin was given nightly to all patients in an open-label design. Sleep was objectively monitored in a subgroup of 22 patients using wrist actigraphy. Fasting glucose, fructosamine, insulin, C-peptide, triglycerides, total cholesterol, high-density and low-density lipoprotein cholesterol, and some antioxidants, as well as glycosylated hemoglobin (HbA1c) levels were measured at baseline and at the end of the study. All concomitant medications were continued throughout the study.

RESULTS

No significant changes in serum glucose, fructosamine, insulin, C-peptide, antioxidant levels or blood chemistry were observed after 3 weeks of prolonged-release melatonin treatment. Sleep efficiency, wake time after sleep onset, and number of awakenings improved significantly with prolonged-release melatonin as compared with placebo. Following 5 months of prolonged-release melatonin treatment, mean HbA1c (±standard deviation) was significantly lower than at baseline (9.13% ± 1.55% versus 8.47% ± 1.67%, respectively, P = 0.005).

CONCLUSION

Short-term use of prolonged-release melatonin improves sleep maintenance in type 2 diabetic patients with insomnia without affecting glucose and lipid metabolism. Long-term prolonged-release melatonin administration has a beneficial effect on HbA1c, suggesting improved glycemic control.

Nightly treatment of primary insomnia with prolonged release melatonin for 6 months: a randomized placebo controlled trial on age and endogenous melatonin as predictors of efficacy and safety

BACKGROUND

Melatonin is extensively used in the USA in a non-regulated manner for sleep disorders. Prolonged release melatonin (PRM) is licensed in Europe and other countries for the short term treatment of primary insomnia in patients aged 55 years and over. However, a clear definition of the target patient population and well-controlled studies of long-term efficacy and safety are lacking. It is known that melatonin production declines with age. Some young insomnia patients also may have low melatonin levels. The study investigated whether older age or low melatonin excretion is a better predictor of response to PRM, whether the efficacy observed in short-term studies is sustained during continued treatment and the long term safety of such treatment.

METHODS

Adult outpatients (791, aged 18-80 years) with primary insomnia, were treated with placebo (2 weeks) and then randomized, double-blind to 3 weeks with PRM or placebo nightly. PRM patients continued whereas placebo completers were re-randomized 1:1 to PRM or placebo for 26 weeks with 2 weeks of single-blind placebo run-out. Main outcome measures were sleep latency derived from a sleep diary, Pittsburgh Sleep Quality Index (PSQI), Quality of Life (World Health Organzaton-5) Clinical Global Impression of Improvement (CGI-I) and adverse effects and vital signs recorded at each visit.

RESULTS

On the primary efficacy variable, sleep latency, the effects of PRM (3 weeks) in patients with low endogenous melatonin (6-sulphatoxymelatonin [6-SMT] <or=8 microg/night) regardless of age did not differ from the placebo, whereas PRM significantly reduced sleep latency compared to the placebo in elderly patients regardless of melatonin levels (-19.1 versus -1.7 min; P = 0.002). The effects on sleep latency and additional sleep and daytime parameters that improved with PRM were maintained or enhanced over the 6-month period with no signs of tolerance. Most adverse events were mild in severity with no clinically relevant differences between PRM and placebo for any safety outcome.

CONCLUSIONS

The results demonstrate short- and long-term efficacy and safety of PRM in elderly insomnia patients. Low melatonin production regardless of age is not useful in predicting responses to melatonin therapy in insomnia. The age cut-off for response warrants further investigation.

NEU-P11, a novel melatonin agonist, inhibits weight gain and improves insulin sensitivity in high-fat/high-sucrose-fed rats

Evidences indicate that a complex relationship exists among sleep disorders, obesity and insulin resistance. NEU-P11 is a novel melatonin agonist used in treatment of psychophysiological insomnia, and in animal studies NEU-P11 showed sleep-promoting effect. In this study, we applied NEU-P11 on obese rats to assess its potential melatoninergic effects in vivo. Obese models were established using high-fat/high-sucrose-fed for 5 months. NEU-P11 (10mg/kg)/melatonin (4mg/kg)/vehicle were administered by a daily intraperitoneal injection respectively for 8 weeks. Our results showed that NEU-P11 or melatonin inhibited both body weight gain and deposit of abdominal fat with no influence on food intake. The impaired insulin sensitivity and antioxidative potency were improved and the levels of plasma glucose, total cholesterol (TC), triglycerides (TG) decreased with an increased in HDL-cholesterol (HDL-c) after NEU-P11 or melatonin administration. These data suggest that NEU-P11, like melatonin, decreased body weight gain and improved insulin sensitivity and metabolic profiles in obese rats. We conclude that NEU-P11 has a melatoninergic effect on regulating body weight in obese rats and also improving metabolic profiles and efficiently enhancing insulin sensitivity.

Prolonged-release melatonin improves sleep quality and morning alertness in insomnia patients aged 55 years and older and has no withdrawal effects

Melatonin, secreted nocturnally by the pineal gland, is an endogenous sleep regulator. Impaired melatonin production and complaints on poor quality of sleep are common among the elderly. Non-restorative sleep (perceived poor quality of sleep) and subsequently poor daytime functioning are increasingly recognized as a leading syndrome in the diagnostic and therapeutic process of insomnia complaints. The effects of 3-weeks prolonged-release melatonin 2 mg (PR-melatonin) versus placebo treatment were assessed in a multi-center randomized placebo-controlled study in 170 primary insomnia outpatients aged > or =55 years. Improvements in quality of sleep (QOS) the night before and morning alertness (BFW) were assessed using the Leeds Sleep Evaluation Questionnaire and changes in sleep quality (QON) reported on five categorical unit scales. Rebound insomnia and withdrawal effects following discontinuation were also evaluated. PR-melatonin significantly improved QOS (-22.5 versus -16.5 mm, P = 0.047), QON (0.89 versus 0.46 units; P = 0.003) and BFW (-15.7 versus -6.8 mm; P = 0.002) compared with placebo. The improvements in QOS and BFW were strongly correlated (Rval = 0.77, P < 0.001) suggesting a beneficial treatment effect on the restorative value of sleep. These results were confirmed in a subgroup of patients with a greater symptom severity. There was no evidence of rebound insomnia or withdrawal effects following treatment discontinuation. The incidence of adverse events was low and most side-effects were judged to be of minor severity. PR-melatonin is the first drug shown to significantly improve quality of sleep and morning alertness in primary insomnia patients aged 55 years and older-suggesting more restorative sleep, and without withdrawal symptoms upon discontinuation.

Efficacy of prolonged release melatonin in insomnia patients aged 55-80 years: quality of sleep and next-day alertness outcomes

OBJECTIVE

Melatonin, the hormone produced nocturnally by the pineal gland, serves as a circadian time cue and sleep-anticipating signal in humans. With age, melatonin production declines and the prevalence of sleep disorders, particularly insomnia, increases. The efficacy and safety of a prolonged release melatonin formulation (PR-melatonin; Circadin* 2 mg) were examined in insomnia patients aged 55 years and older.

DESIGN

Randomised, double blind, placebo-controlled.

SETTING

Primary care.

METHODOLOGY

From 1248 patients pre-screened and 523 attending visit 1, 354 males and females aged 55-80 years were admitted to the study, 177 to active medication and 177 to placebo. The study was conducted by primary care physicians in the West of Scotland and consisted of a 2-week, single blind, placebo run-in period followed by a 3-week double blind treatment period with PR-melatonin or placebo, one tablet per day at 2 hours before bedtime.

MAIN OUTCOME MEASURES

Responder rate (concomitant improvement in sleep quality and morning alertness on Leeds Sleep Evaluation Questionnaire [LSEQ]), other LSEQ assessments, Pittsburgh Sleep Quality Index (PSQI) global score, other PSQI assessments, Quality of Night and Quality of Day derived from a diary, Clinical Global Improvement scale (CGI) score and quality of life (WHO-5 well being index).

RESULTS

Of the 354 patients entering the active phase of the study, 20 failed to complete visit 3 (eight PR-melatonin; 12 Placebo). The principal reasons for drop-out were patient decision and lost to follow-up. Significant differences in favour of PR-melatonin vs. placebo treatment were found in concomitant and clinically relevant improvements in quality of sleep and morning alertness, demonstrated by responder analysis (26% vs. 15%; p = 0.014) as well as on each of these parameters separately. A significant and clinically relevant shortening of sleep latency to the same extent as most frequently used sleep medications was also found (-24.3 vs.-12.9 minutes; p = 0.028). Quality of life also improved significantly (p = 0.034).

CONCLUSIONS

PR-melatonin results in significant and clinically meaningful improvements in sleep quality, morning alertness, sleep onset latency and quality of life in primary insomnia patients aged 55 years and over.

TRIAL REGISTRATION

The trial was conducted prior to registration being introduced.

A model system for increasing the intensity of whole-cell biocatalysis: investigation of the rate of oxidation of D-sorbitol to L-sorbose by thin bi-layer latex coatings of non-growing Gluconobacter oxydans

We developed a novel <50-microm thick nano-porous bi-layer latex coating for preserving Gluconobacter oxydans, a strict aerobe, as a whole cell biocatalyst. G. oxydans was entrapped in an acrylate/vinyl acetate co-polymer matrix (T (g) approximately 10 degrees C) and cast into 12.7-mm diameter patch coatings (cellcoat) containing approximately 10(9) CFU covered by a nano-porous topcoat. The oxidation of D-sorbitol to L-sorbose was used to investigate the coating catalytic properties. Intrinsic kinetics was studied in microbioreactors using a pH 6.0 D-sorbitol, phosphate, pyruvate (SPP) non-growth medium at 30 degrees C, and the Michaelis-Menten constants determined. By using a diffusion cell, cellcoat and topcoat diffusivities, optimized by arresting polymer particle coalescence by glycerol and/or sucrose addition, were determined. Cryo-FESEM images revealed a two-layer structure with G. oxydans surrounded by <40-nm pores. Viable cell density, cell leakage, and oxidation kinetics in SPP medium for >150 h were investigated. Even though the coatings were optimized for permeability, approximately 50% of G. oxydans viability was lost during cellcoat drying and further reduction was observed as the topcoat was added. High reaction rates per unit volume of coating (80-100 g/L x h) were observed which agreed with predictions of a diffusion-reaction model using parameters estimated by independent experiments. Cellcoat effectiveness factors of 0.22-0.49 were observed which are 20-fold greater than any previously reported for this G. oxydans oxidation. These nano-structured coatings and the possibility of improving their ability to preserve G. oxydans viability may be useful for engineering highly reactive adhesive coatings for multi-phase micro-channel and membrane bioreactors to dramatically increase the intensity of whole-cell oxidations.

Melatonin reduces night blood pressure in patients with nocturnal hypertension

PURPOSE

Nocturnal hypertension is associated with a high risk of morbidity and mortality. A blunted nocturnal surge in melatonin excretion has been described in nondipping hypertensive patients. We therefore studied the potency of melatonin to reduce nighttime blood pressure (BP) in treated hypertensive patients with nocturnal hypertension.

PATIENTS AND METHODS

Thirty-eight treated hypertensive patients (22 males, mean age 64+/-11 years) with confirmed nocturnal hypertension (mean nighttime systolic BP >125 mm Hg), according to repeated 24-hour ambulatory blood pressure monitoring (ABPM), were randomized in a double-blind fashion to receive either controlled release (CR)-melatonin 2 mg or placebo 2 hours before bedtime for 4 weeks. A 24-hour ABPM was then performed.

RESULTS

Melatonin treatment reduced nocturnal systolic BP significantly from 136+/-9 to 130+/-10 mm Hg (P=.011), and diastolic BP from 72+/-11 to 69+/-9 mm Hg (P=.002), whereas placebo had no effect on nocturnal BP. The reduction in nocturnal systolic BP was significantly greater with melatonin than with placebo (P=.01), and was most prominent between 2:00 AM and 5:00 AM (P=.002).

CONCLUSIONS

Evening CR-melatonin 2 mg treatment for 4 weeks significantly reduced nocturnal systolic BP in patients with nocturnal hypertension. Thus, an addition of melatonin 2 mg at night to stable antihypertensive treatment may improve nocturnal BP control in treated patients with nocturnal hypertension.

Improvement of sleep quality by controlled-release melatonin in benzodiazepine-treated elderly insomniacs

Benzodiazepines are widely used in the elderly population for the initiation of sleep. However, very frequently, complaints about poor sleep maintenance persist despite benzodiazepine treatment. Melatonin, a hormone produced by the pineal gland at night, is involved in the regulation of the sleep/wake cycle. Melatonin production decreases with age and can also be inhibited by benzodiazepines. We have recently reported on the association between insomnia and impaired melatonin output in the elderly. In the present study we have investigated the efficacy of melatonin replacement therapy in improving sleep in 21 elderly subjects who have been taking benzodiazepines and had low melatonin output. In a randomized, double-blind, crossover designed study the subjects were treated for three weeks with 2 mg per night of controlled-release melatonin and for 3 weeks with placebo, 2 h before desired bedtime with a 1-week washout period between treatment periods. Subjects' sleep was assessed by wrist actigraphy. Melatonin treatment significantly increased sleep efficiency and total sleep time and decreased wake after sleep onset, sleep latency, number of awakenings and fragmental index, as compared to placebo. The results of our study indicate that melatonin replacement therapy can improve sleep quality in the elderly and that the beneficial effects are augmented in the presence of benzodiazepines.

Nocturnal 6-sulfatoxymelatonin excretion in insomnia and its relation to the response to melatonin replacement therapy

PURPOSE

Melatonin, which is produced by the pineal gland at night, is an endogenous sleep regulator. Both sleep disorders and impaired melatonin production are common among the elderly. We examined the excretion of the major melatonin metabolite 6-sulfatoxymelatonin in insomnia patients aged >or=55 years and its relation with the subsequent response to melatonin therapy.

METHODS

We studied 517 insomnia patients, along with 29 age-matched and 30 younger healthy volunteers. Nocturnal urinary 6-sulfatoxymelatonin excretion was assessed between 10 pm and 10 am. Three hundred and ninety-six of the insomnia patients were treated for 2 weeks with placebo and for 3 weeks with 2 mg per night of controlled-release melatonin, of which 372 provided complete datasets. Clinical response, assessed with the Leeds Sleep Evaluation Questionnaire, was defined as an improvement of 10 mm or more on the visual analog scales.

RESULTS

Mean (+/- SD) 6-sulfatoxymelatonin excretion was lower in the insomnia patients (9.0 +/- 8.3 microg per night) than in volunteers of the same age (18.1 +/- 12.7 microg per night, P <0.05) and in younger volunteers (24.2 +/- 11.9 microg per night, P <0.05). About 30% of patients (112/372) excreted <or=3.5 microg of sulfatoxymelatonin per night, which is considered to be lower than normal for this age group. These "low excretors" had a significantly higher response to melatonin replacement therapy (58% [65/112] vs. 47% [122/260], P <0.05).

CONCLUSION

Low nocturnal melatonin production is associated with insomnia in patients aged 55 years or older, and identifies patients who are somewhat more likely to respond to melatonin replacement.

Impaired nocturnal melatonin secretion in non-dipper hypertensive patients

BACKGROUND

Melatonin plays a role in the biologic regulation of circadian rhythms, including sleep. Melatonin has also been shown to modulate vascular smooth muscle tone and to induce hemodynamic effects in humans.

OBJECTIVE

To evaluate whether melatonin plays a role in the circadian rhythm of blood pressure in hypertensive patients.

METHODS

Sixteen elderly patients with essential hypertension were evaluated. Patients were defined as either dippers (DIP, n = 8) or non-dippers (NDIP, n = 8) according to the nocturnal change in the mean arterial pressure (MAP). 6-Sulfatoxymelatonin (6-SMT), the main melatonin metabolite, was determined by enzyme-linked immunosorbent assay (ELISA) in two separate urine collections, one in the daytime and one during the night.

RESULTS

Both groups of DIP and NDIP hypertensives were comparable in regard to age and sex. During the night, the mean arterial pressure decreased by 10.3 +/- 2.2% in the DIP and increased by 7.5 +/- 1.7% in the NDIP group (p < 0.01). Daily 6-SMT was comparable in DIP (3.28 +/- 0.87 microg/12 h) and NDIP (2.31 +/- 0.68 microg/12 h) (p = 0.39). However, while the DIP presented the physiological nocturnal increase in urinary 6-SMT (mean 8.19 +/- 1.68 microg/ 12 h), this surge of melatonin production was missing in NDIP in whom nocturnal urinary 6-SMT concentrations were not significantly different from daily levels (mean 2.56 +/- 0.79 microg/12 h). The nocturnal change in urinary 6-SMT excretion was positively correlated to the nocturnal change in MAP (R = 0.54; p = 0.031).

CONCLUSIONS

NDIP hypertensive patients differ from DIP hypertensives by having an impaired nocturnal melatonin secretion. Thus, melatonin may play a role in the circadian rhythm of blood pressure in hypertensive patients.

Cross-cultural validation of the Leeds sleep evaluation questionnaire (LSEQ) in insomnia patients

The Leeds sleep evaluation questionnaire (LSEQ) is a standardized self-reporting instrument comprising ten 100 mm visual analogue scales that pertain to the ease of getting to sleep (GTS), quality of sleep (QOS), ease of awakening from sleep (AFS) and alertness and behaviour following wakefulness (BFW). Although the LSEQ has been used in a variety of populations, published psychometric data on insomnia patients are limited. The LSEQ reliability and construct validity was evaluated in 396 French insomnia patients aged 55 years and over, who were treated with placebo (2 weeks) and melatonin (3 weeks). The results supported LSEQ internal consistency, reliability and construct validity with minor differences from those of the original English version. Then the internal consistency of the LSEQ was evaluated in 257 insomnia patients (age 20-80 years) in France and Israel who, following a 1 week placebo baseline, were randomized to placebo or melatonin treatment for 3 weeks. Cronbach's alpha and Pearson's r correlation coefficients for placebo and drug treatment conditions (p<0.001 for all) supported LSEQ internal consistency in different treatment and age groups and in different languages. It is concluded that the consistency, reliability and validity of the four LSEQ domains allows them to be singled out as independent outcome variables in cross cultural sleep research and clinical practice in adult and elderly patients with insomnia.

Effect of controlled-release melatonin on sleep quality, mood, and quality of life in subjects with seasonal or weather-associated changes in mood and behaviour

This study aimed to explore the effects of melatonin on sleep, waking up and well being in subjects with varying degrees of seasonal or weather-associated changes in mood and behaviour. Fifty-eight healthy adults exhibiting subsyndromal seasonal affective disorder (s-SAD) and/or the negative or positive type of weather-associated syndrome (WAS) were randomised to either 2 mg of sustained-release melatonin or placebo tablets 1-2 h before a desired bedtime for 3 weeks. Outcome measures were changes from baseline in sleep quality, sleepiness after waking, atypical depressive symptoms and health-related quality of life by week three. Early morning salivary melatonin concentrations were measured at baseline and treatment cessation in all subjects. Melatonin administration significantly improved the quality of sleep (P=0.03) and vitality (P=0.02) in the subjects with s-SAD, but attenuated the improvement of atypical symptoms and physical parameters of quality of life compared to placebo in the subjects with WAS, positive type.

Subjective assessment of the effects of CNS-active drugs on sleep by the Leeds sleep evaluation questionnaire: a review

The Leeds sleep evaluation questionnaire (LSEQ) comprises ten self-rating 100 mm line analogue questions concerned with sleep and early morning behaviour. A literature search identified 83 studies in peer-reviewed journals that reported the use of the LSEQ for psychopharmacological investigations of drug effects on self-reported aspects of sleep. High internal consistency and reliability of the questionnaire have been demonstrated. Findings from studies involving a variety of psychoactive agents indicated that the LSEQ was able to quantify subjective impressions of sleep and waking and the effects of drugs in healthy volunteers, depressed and insomnia patients. In accordance with their known activity profile nocturnal administration of sedative hypnotic agents and antihistamines induced dose-related improvements in self-reported ease of getting to sleep, and quality of sleep but a decrease in alertness and behavioural integrity the following morning. Psychostimulants, on the other hand, impaired subjective ratings of sleep and increased early morning alertness. Antidepressants and certain anxiolytic agents improved both self-reported sleep aspects and early morning alertness. Treatment effects measured by the LSEQ corresponded to those measured for the same drugs by other assessment methods. These data indicate that the LSEQ is a robust and reliable instrument for psychopharmacological evaluations. Self-evaluations of sleep, as obtained by the LSEQ, can therefore provide consistent and meaningful measures for estimating the effectiveness of sleep modulators and sedative-hypnotic drugs.

Massage therapy by mothers enhances the adjustment of circadian rhythms to the nocturnal period in full-term infants

The objective of this study was to investigate the effect of massage therapy on phase adjustment of rest-activity and melatonin secretion rhythms to the nocturnal period in full-term infants. Rest-activity cycles of infants (measurement 1, n = 16) were measured by actigraphy before and after 14 days of massage therapy (starting at age 10 [+/-4] d) and subsequently at 6 and 8 weeks of age. 6-Sulphatoxymelatonin excretion was assessed in urine samples at 6, 8, and 12 weeks of age (measurement 2, n = 21). At 8 weeks the controls revealed one peak of activity at approximately 12 midnight (11 p.m.-3 a.m.) and another one at approximately 12 noon (11 a.m.-3 p.m.), whereas in the treated group, a major peak was early in the morning (3 a.m.-7 a.m.) and a secondary peak in the late afternoon (3 p.m.-7 p.m.). At 12 weeks, nocturnal 6-sulphatoxymelatonin excretions were significantly higher in the treated infants (1346.38 +/- 209.40 microg/night vs 823.25 +/- 121.25 microg/night, respectively; <.05). It is concluded that massage therapy by mothers in the perinatal period serves as a strong time cue, enhancing coordination of the developing circadian system with environmental cues.

Neuroimmunotherapy of untreatable metastatic solid tumors with subcutaneous low-dose interleukin-2, melatonin and naltrexone: modulation of interleukin-2-induced antitumor immunity by blocking the opioid system

OBJECTIVES

The preliminary applications of the psychoneuroimmunological knowledges to the treatment of human diseases have confirmed the possibility to amplify IL-2-dependent anticancer immunity by the pineal hormone melatonin (MLT) or by opioid antagonist, such as naltrexone (NTX), which act by activating TH1 lymphocytes or suppressing TH2 lymphocytes, respectively. At present, however, there are no data about the immunobiological effects of a concomitant administration of both MLT and NTX on IL-2-induced anticancer immunity. This preliminary study was carried out to evaluate whether the association of NTX may further enhance the lymphocytosis induced by the neuroimmunotherapy with IL-2 plus MLT.

MATERIALS & METHODS

The study included 14 consecutive untreatable metastatic solid tumor patients. According to a cross-over randomized study, the patients were treated during two consecutive immunotherapeutic cycles at 21-day intervals with IL-2 plus MLT alone or with IL-2 plus MLT plus NTX. IL-2 was injected subcutaneously at 3 MIU/day for 6 days/week for 4 weeks, MLT was given orally at 20 mg /day in the evening every day, and NTX was given orally at 100 mg in the morning every next day. For the immune evaluation, venous blood samples were drawn before the onset of treatment and at weekly intervals.

RESULTS

Lymphocyte mean number significantly increased after both IL-2 plus MLT and IL-2 plus MLT plus NTX. However, the concomitant administration of NTX induced a significantly higher increase in lymphocyte mean number with respect to that achieved with IL-2 plus MLT alone. In contrast, the increase in eosinophil mean number was significantly higher on IL-2 plus MLT alone.

CONCLUSIONS

This preliminary study shows that the association of NTX further amplifies the lymphocytosis obtained by IL-2 plus MLT. Since the lymphocytosis represents the most important favourable prognostic variable predicting the anticancer efficacy of IL-2 immunotherapy, it is probable that a cancer neuroimmunotherapy with IL-2 plus both MLT and NTX to activate TH1 and suppress TH2 cells respectively, may deserve more promising results in the treatment of human neoplasms according to the psychoneuroimnunological knowledge.

Melatonin production in infants

This study investigated the relationships of the excretion of the melatonin metabolite, 6-sulfatoxymelatonin, to prenatal, natal, and postnatal variables and its possible relation to psychomotor development. nocturnal urinary excretion of 6-sulfatoxymelatonin was studied over a 13-hour period in 355 term infants at 8 weeks of age (n = 320) and 16 weeks of age (n = 96). data on a variety of perinatal factors including pregnancy course, delivery, early postnatal course, birth weight, medical problems, growth (length, weight, and head circumference), and psychomotor development were collected at 1, 3, 6, 9, 12, and 18 months. the relationship between nocturnal 6-sulfatoxymelatonin excretion at 8 and 16 weeks of age and these factors was investigated and analyzed. 6-sulfatoxymelatonin levels at 16 weeks of age were significantly lower in infants with abnormal vs normal development at 3 months of age (7.27 + 1.44 vs 7.97 + 1.06, p = 0.05) as well as at 6 months of age (7.15 + 1.29 vs 7.95 + 1.10, p = 0.04). no other significant relation was evident among growth, perinatal complications, medical problems, and 6-sulfatoxymelatonin excretion at 8 weeks of age and at 16 weeks of age. low melatonin excretion in the first weeks of life correlates with delayed psychomotor achievements at 3 and 6 months of age. this association suggests a causal or predictive link between melatonin and neurodevelopment in infants.

Melatonin rhythms in stroke patients

Very little is known regarding melatonin's circadian rhythm in stroke patients. We compared urinary-sulfatoxymelatonin (6-SMT), its major metabolite, in 11 extensive cortical and seven deep or lacunar stroke patients on day 3 or 4 and day 10 post-stroke. Urinary 6-SMT and creatinine measured every 4 h for 24 h starting at 06:00 h significantly fluctuated during the day in both types of stroke and did not differ between day 3 or 4 and day 10 post-stroke. However, in extensive cortical lesions, a delay in the 6-SMT excretion was observed in the first post-stroke days compared to day 10. We conclude that circadian oscillator is preserved in extensive cortical as well as in deep and lacunar strokes. Extensive cortical stroke might delay the melatonin surge during the first post-stroke days.

Melatonin treatment for tardive dyskinesia: a double-blind, placebo-controlled, crossover study

BACKGROUND

Antipsychotics remain the mainstay of drug intervention in the management of schizophrenia. However, long-term treatment with antipsychotics is associated with a variety of movement disorders, the most disabling of which is tardive dyskinesia (TD), which occurs in up to 50% of patients hospitalized with chronic schizophrenia. The pathophysiology of TD is still unclear and no definite treatment exists. Both dopamine receptor supersensitivity and oxidative stress-induced neurotoxicity in the nigrostriatal system are apparently implicated. The pineal hormone melatonin is a potent antioxidant and attenuates dopaminergic activity in the striatum and dopamine release from the hypothalamus. Thus, it may have a beneficial effect for both the treatment and prevention of TD.

METHODS

Using a double-blind, placebo-controlled, crossover study, we evaluated the efficacy of 10 mg/d of melatonin for 6 weeks in 22 patients with schizophrenia and TD. The primary outcome measure was the change from baseline in Abnormal Involuntary Movement Scale (AIMS) score.

RESULTS

The decrease (mean +/- SD) in AIMS score was 2.45 +/- 1.92 for the melatonin and 0.77 +/- 1.11 for the placebo treatment groups (P<.001). No adverse events or side effects were noted.

CONCLUSION

This is the first clinical evidence for efficacy of melatonin in the treatment of TD.

A review on cancer--psychospiritual status interactions

With the advances in the knowledge of neuroimmunomodulation, a new era of investigations about the chemical basis of the state of mind has been initiated. Both emotions and states of spiritual consciousness may influence immune functions and cancer growth. Stress, anxiety and depressive states are associated with immunosuppression and enhanced frequency of tumors. On the other hand, the states of sexual pleasure and spiritual joy enhance the immune efficacy, by counteracting tumor onset and dissemination. The biochemistry of pleasure and immunostimulation is mainly mediated by pineal indoles and cannabinergic substances, whereas that of stress, anxiety and depression is associated with enhanced production of adrenal steroids, opioids and catecholamines. The sexual repression would allow a progressive immunosuppression through a profound damage in the biochemistry of pleasure. Therefore, a better definition of psychospiritual status-associated neuroimmunochemistry could allow us to improve the immune dysfunction by acting on the same neuroendocrine secretions which are involved in mediating the psychic influence on the immunity, including that against cancer.

Melatonin production in healthy infants: evidence for seasonal variations

The objective of this study was to determine the normal range of nocturnal urinary excretion of the major melatonin metabolite, 6-sulfatoxymelatonin (6SMT) in a large sample of healthy full-term infants (8 and 16 wk old) and assess whether the endogenous production of melatonin changes with season. 6SMT was assessed in urine samples extracted from disposable diapers removed from full-term, 8- (n = 317) and 16-wk-old (n = 93) infants over the nocturnal period (19:00-08:00 h). In addition, 6SMT was assessed in 8-wk-old (n = 35) healthy infants over the entire 24-h period. 6SMT was determined by an ELISA assay. 6SMT excretion at 8 wk of age exhibited diurnal variations with (mean +/- SD) 61 +/- 18% of the daily production excreted during the nocturnal period regardless of season. The nocturnal 6SMT values in the entire cohort (at 8 as well as 16 wk of age) were found to significantly depart from normal distribution (Kolmogorov-Smirnov test). A normal distribution was obtained using a natural base logarithmic (ln) transformation of the data. The normal range (2.5-97.5 percentile of the ln 6SMT excretion per night) was thus defined as 4.66-8.64 (106-5646 ng/night) for 8-wk-old and 5.19-9.67 (180-15,820 ng/night) for 16-wk-old infants. A significant effect of the month of birth on 6SMT production at the age of 8 wk was found (ANOVA, p < 0.002) with maximal levels produced by infants born in June (summer solstice) and minimal excretion in infants born in December (winter solstice). Short-photoperiod-born infants excreted on average about threefold less 6SMT compared with long-photoperiod-born infants (t test, p = 0. 01). The seasonal variations were no longer present at 16 wk of age. No effect of breast-feeding at the time of sampling on seasonality of 6SMT was found. Normal ranges for the nocturnal urinary excretion of 6SMT in full-term infants at 8 and 16 wk of age are defined. This enables the evaluation of nocturnal 6SMT excretion as a prognostic and diagnostic factor for child development. The strong effect of season on the normal excretion of nocturnal 6SMT at 8 but not 16 wk of age suggests prenatal influence of the photoperiod on the ontogeny of melatonin.

First-night effect of melatonin treatment in patients with chronic schizophrenia

The first-night effect (FNE) is the tendency for individuals to sleep worse than normal during their first night of polysomnographic sleep evaluation. FNE reflects the adaptive increase of alertness and perhaps the stress resulting from an unfamiliar sleeping environment. This effect is usually absent in patients with chronic schizophrenia. Melatonin (N-acetyl-5-methoxy-tryptamine), the hormone secreted by the pineal gland at night, has been found to improve sleep in elderly patients with insomnia and recently in patients with chronic schizophrenia. The authors used FNE as a marker to explore the neurobehavioral responses of patients with chronic schizophrenia to melatonin treatment. In a randomized, double-blind, crossover trial, 14 patients with chronic schizophrenia were administered melatonin (2 mg in a controlled-release formulation) or placebo for 3 weeks with a 1-week washout between treatment periods. Polysomnography was performed during the last two consecutive nights of each treatment period. The following significant FNEs were observed with melatonin treatment: (1) rapid eye movement sleep latency was longer; (2) sleep efficiency was lower; and (3) the duration of wakefulness during sleep was lower on the first night than on the second night. These effects were not found when the patients received a placebo. The FNE was manifested regardless of whether melatonin was administered before or after the placebo treatment period. For the first time, these results show that melatonin treatment exaggerates FNE in patients with chronic schizophrenia, thereby suggesting an improved ability of these patients to mobilize alertness in unfamiliar surroundings.

Clinical trials of controlled-release melatonin in children with sleep-wake cycle disorders

This is the first study to examine effective doses of controlled-release (CR) melatonin in children with chronic sleep wake cycle disorders. All 42 subjects had severe neurodevelopmental difficulties. Initially, a randomized double-blinded cross-over design was used in 16 children, comparing the effectiveness of fast-release (FR) and CR melatonin. In the remainder of the patients, the CR melatonin was studied on a clinical basis. The effectiveness of treatment was assessed by sleep charts and clinical follow-up. Emphasis was placed on the judgement of the parents, who had guidance from the physicians. The average final CR melatonin dose in the 42 patients was 5.7 mg (2-12 mg). The studies showed that the FR melatonin was most effective when there was only delayed sleep onset, but CR formulations were more useful for sleep maintenance. Children appeared to require higher doses than adults.

Low melatonin production in infants with a life-threatening event

This study compares the urinary excretion of the main melatonin metabolite, 6-sulfatoxymelatonin (6SMT), in infants who have and have not experienced a life-threatening event (ALTE). 6SMT was assessed in the following groups of infants: 15 infants with ALTE for whom home monitoring had been recommended, 15 infants who had had an abrupt cyanotic apneic event but did not require mouth-to-mouth resuscitation, 15 siblings of those who had died from sudden infant death syndrome (SIDS), and 35 age-matched healthy comparison infants. All 80 infants were between 48 and 58 weeks of postconceptional age. On a double-blind basis, the total amount of 6SMT excreted over 24 hours and the diurnal rhythm in the rate of 6SMT excretion were assessed using urine samples taken from disposable diapers (nappies). The mean daily excretion of 6SMT was significantly lower in the ALTE (1,588 ng/24 hour) than in the comparison infants (3,961 ng/24 hour). No such difference was found between the infants with a cyanotic apneic event (3,268 ng/24 hour) and the SIDS siblings (2,962 ng/24 hour). The diurnal 6SMT rhythms in the ALTE infants were characterized by lower 24-hour mean and amplitude values, whereas the time of peak and nadir excretion rates (07:15 to 08:45 hours and 14:45 to 16:15 hours respectively) was similar in all four infant groups. Follow-up of the ALTE infants, performed 6 to 8 weeks later (59 to 66 weeks of postconceptional age), revealed that 6SMT excretion increased in all of them, suggesting a delayed ontogeny rather than permanent deficiency of melatonin production in ALTE.

Melatonin improves sleep quality of patients with chronic schizophrenia

BACKGROUND

Accumulating evidence indicates decreased melatonin levels in patients with schizophrenia. Insomnia, mainly difficulty in falling asleep at night, is commonly reported in this population. Association of insomnia with low or abnormal melatonin rhythms has been repeatedly documented. Melatonin is an endogenous sleep promoter in humans. We hypothesized that insomnia in patients with schizophrenia may be partially due to diminished melatonin output. In this study, we measured melatonin output in patients with chronic schizophrenia and assessed the effects of melatonin replacement on their sleep quality.

METHOD

In a randomized, double-blind, cross-over, clinically based trial, 19 patients with DSM-IV schizophrenia who were treated with the normal treatment regimen were given melatonin (2 mg, controlled release) or placebo for 2 treatment periods of 3 weeks each with 1 week washout between treatment periods (7 weeks total). For measuring endogenous melatonin production, urine was collected from each patient every 3 hours between 9:00 p.m. and 9:00 a.m. Actigraphy was performed for 3 consecutive nights at the end of each period. Activity- and rest-derived sleep parameters were compared for the whole population with treatment arm as the intervening variable. A separate analysis was performed for patients subgrouped into high versus low sleep efficiency.

RESULTS

All patients had low melatonin output. Melatonin replacement significantly improved rest-derived sleep efficiency compared with placebo (83.5% vs. 78.2%, p = .038) in this population. Improvement of sleep efficiency was significantly greater (p < .0014) in low-efficiency (80% vs. 67%) than high-efficiency sleepers (88% vs. 90%). In addition, during melatonin therapy, tendencies toward shortened sleep latency (by 40 minutes, p < .056) and increased sleep duration (by 45 minutes, p < .078) were observed in low- but not high-efficiency sleepers.

CONCLUSION

Melatonin improves sleep efficiency in patients with schizophrenia whose sleep quality is low.