Результаты поиска

Effects of short-day photoperiods and of N-(2,4-dinitrophenyl)-5-methoxytryptamine, a putative melatonin antagonist, on melatonin synthesis in the Harderian gland of the Syrian hamster, Mesocricetus auratus.

The Harderian glands of Syrian hamsters contain melatonin and the enzymes N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) which synthesize melatonin from serotonin. Because the Harderian glands share this metabolic pathway with the pineal gland, we examined the effects of short-day photoperiods, which stimulate pineal-mediated gonadal regression, and N-(2,4-dinitrophenyl)-5-methoxytryptamine (ML-23), which has been described as a melatonin antagonist, on melatonin synthesis in the Harderian glands of the hamster. Harderian glands of male hamsters kept in short days had …

Time-of-Day Impacts Uterine Circadian Rhythms and Response to Oxytocin: Comparison of Uterine Function in Melatonin-Deficient C57BL/6 Versus Melatonin Proficient CBA/B6 Hybrid Mice.

Reaching term gestation requires a complex interplay between the uterus and hormonal signals regulating its contractile profile. Most pregnancy-associated hormones vary in their overall level of release throughout pregnancy, but also have a circadian release pattern, including progesterone, oxytocin, and melatonin. It remains poorly understood how the circadian release of hormones impacts uterine function. To determine how time-of-day, mouse strain, and melatonin proficiency were associated with the uterotonic efficacy of oxytocin, the primary hormone promoting uterine contractions, we used me…

Comparison between melatonin versus melatonin and photobiomodulation versus photobiomodulation in the treatment of Alopecia X in German Spitz dogs: Clinical, randomized, double-blind, parallel, non-inferiority protocol.

Canine Alopecia X is a non-inflammatory hair loss disorder of unknown etiology that predominantly affects German Spitz dogs. Treatment modalities include hormone and/or melatonin supplementation and low trauma microneedling. Melatonin influences hair growth and pigmentation in several species and presents a low risk of adverse effects when used in dogs with Alopecia X. Photobiomodulation (PBM) is frequently used in human androgenetic alopecia and alopecia areata; despite this, PBM remains unexplored in canine Alopecia X. To address this knowledge gap, sixty dogs of both sexes will be randomly …

Мелатонин за пределами хронобиологии: интеграция фармакокинетики, прогнозирование дозы и клинические данные.

Мелатонин установлен в качестве регулятора времени и сна в циркадиане, в то время как более широкий спектр зависящих от рецептора и независимых от рецептора биологических эффектов вызвал интерес к дополнительным видам терапевтического применения. В этом обзоре критически рассматривается вопрос о том, можно ли интерпретировать эти предлагаемые последствия в фармакологических рамках, основанных на воздействии. Мы интегрируем недавние доклинические и клинические данные с фармакокинетиками перорального и внутривенного мелатонина и с обычным дифференциальном уравнением (ОДВ) - прогнозом воздействия

Совпадение в аннотации оригинала
Melatonin is established as a regulator of circadian timing and sleep, while a wider range of receptor-dependent and receptor-independent biological effects has generated interest in additional therapeutic applications. This review critically examines whether those proposed effects can be interpreted within an exposure-based pharmacological framework. We int…

Lineage-specific response to melatonin in stomatal regulation across vascular plants.

Melatonin (N-acetyl-5-methoxytryptamine) is a conserved indoleamine that regulates diverse physiological processes, including stomatal movement in angiosperms. However, whether this regulation is conserved across different plant lineages remains uncertain. Here, we examined the stomatal responses to exogenous melatonin in 17 representative plant species: seven angiosperms, two gymnosperms, seven ferns, and one lycophyte. In seed plants, melatonin induced dose-dependent stomatal closure, accompanied by the accumulation of reactive oxygen species (ROS), nitric oxide (NO), and cytosolic Ca2+; thi…

Melatonin in Integrative Oncology: Biological Mechanisms, Therapeutic Evidence and Implementation Strategies.

Melatonin, an endogenous indoleamine primarily synthesized in the pineal gland, has emerged as a promising adjunctive agent within integrative oncology due to its pleiotropic biological actions. Beyond its well-known chronobiological functions, melatonin exerts potent redox-regulatory, anti-inflammatory, oncostatic, and immune-modulating effects that are relevant across multiple stages of carcinogenesis and cancer therapy. Oxidative stress (OS), defined as an imbalance between reactive oxygen and nitrogen species (ROS/RNS) generation and antioxidant defenses, plays a central role in DNA damage…

Melatonin suppresses ILC2-driven airway hyperreactivity via glutathione-dependent metabolic reprogramming.

Allergic asthma is characterized by type 2 inflammation and overnight worsening of symptoms, yet dynamic fluxes in cellular metabolic profiles driving time-of-day variation remain poorly defined. Group 2 innate lymphoid cells (ILC2s) are central mediators of airway hyperreactivity. We identify melatonin as a previously unrecognized regulator of ILC2 metabolism and function. In murine models of allergic airway inflammation, melatonin reduced eosinophilia, type 2 cytokine production, and airway hyperreactivity without altering ILC2 abundance. Mechanistically, melatonin acted independently of can…

Melatonin modulates inflammation in human fetal membranes: an ex vivo approach.

Choriodecidual infection is a major contributor to preterm birth, triggering inflammation in the human fetal membranes, through the release of pro-inflammatory cytokines and chemokines. Melatonin (Mel), a neurohormone produced by the pineal gland and placenta, has well-established anti-inflammatory properties; however, its immunomodulatory effects have not been previously investigated in fetal membranes. The aim of this study was to evaluate the ability of melatonin to exert an anti-inflammatory effect in tissues stimulated with lipopolysaccharide (LPS), as well as to assess the potential invo…

Sleep Deprivation Alters T Cell Dynamics: Melatonin as a Restorative Agent.

Sleep is an essential physiological function regulated by circadian rhythm and homeostatic regulation for emotional and physical health. Conversely, sleep deprivation (SD) is associated with weakened immune system function and overall health, which potentially leads to chronic diseases such as heart disease and diabetes. In this study, we aimed to investigate the role of regulatory T cells (Tregs) in the immune response to SD and the potential therapeutic effect of melatonin in modulating this response. For this purpose, 24 8-week-old male C57BL/6J mice were distributed into 4 groups: control,…

Melatonin ameliorates retinal neurovascular degeneration in Rd1 mice by inhibiting oxidativestress.

Oxidative stress has been involved in the occurrence of retinal photoreceptor degeneration and retinal vascular dysfunctions. This study investigated the effects of melatonin (MLT) on neurovascular changes in rd1 mice, evaluating its therapeutic potential as an antioxidant for retinal degeneration. MLT was administered to rd1 mice at postnatal day 7 (P7), and retinal vascular alterations were assessed using retina flatmounts, while neural and functional changes were evaluated through frozen sections and electroretinography at P14. In vitro, human retinal microvascular endothelial cells (HRMECs…

Gut microbiota in neurological diseases: Melatonin plays an important regulatory role.

Melatonin is a highly conserved molecule produced in the human pineal gland as a hormone. It is known for its essential biological effects, such as antioxidant activity, circadian rhythm regulator, and immunomodulatory effects. The gut is one of the primary known sources of melatonin. The gut microbiota helps produce melatonin from tryptophan, and melatonin has been shown to have a beneficial effect on gut barrier function and microbial population. Dysbiosis of the intestinal microbiota is associated with bacterial imbalance and decreased beneficial microbial metabolites, including melatonin. …

Randomised controlled trial of melatonin for paediatric functional abdominal pain disorders.

AIM: Melatonin seems to have a positive impact on the brain-gut axis and many direct and indirect effects on the gastrointestinal tract. This trial aimed at assessing the efficacy of melatonin combined with Lactobacillus Rhamnosus GG given in the treatment of paediatric patients with functional abdominal pain disorders. METHODS: Forty-two patients aged 4-18 years old who fulfilled the Rome IV Diagnostic Criteria for functional abdominal pain disorders were enrolled. Melatonin 3 or 5 mg in combination with Lactobacillus Rhamnosus GG (group 1, n = 22) or a placebo in combination with Lactobacil…

Melatonin Involved in Protective Effects against Cadmium Stress in Wolffia arrhiza.

Melatonin (MT) is a new plant hormone that protects against adverse environmental conditions. In the present study, the responses of Wolffia arrhiza exposed to cadmium (Cd) and MT were analyzed. Quantitative analysis of MT and precursors of its biosynthesis was performed using LC-MS-MS. The photosynthetic pigments and phytochelatins (PCs) contents were determined using HPLC, while protein and monosaccharides, stress markers, and antioxidant levels were determined using spectrophotometric methods. Interestingly, the endogenous level of MT and its substrates in W. arrhiza exposed to 1-100 µM Cd …

Melatonin alleviates alcoholic liver disease via EGFR-BRG1-TERT axis regulation.

Chronic alcohol consumption causes liver steatosis, cell death, and inflammation. Melatonin (MLT) is reported to alleviate alcoholic liver disease (ALD)-induced injury. However, its direct regulating targets in hepatocytes are not fully understood. In the current study, a cell-based screening model and a chronic ethanol-fed mice ALD model were used to test the protective mechanisms of MLT. MLT ameliorated ethanol-induced hepatocyte injury in both cell and animal models (optimal doses of 10 μmol/L and 5 mg/kg, respectively), including lowered liver steatosis, cell death, and inflammation. RNA-s…

Reduced melatonin levels may facilitate glioblastoma initiation in the subventricular zone.

There is increasing evidence that glioblastoma, a highly aggressive brain tumour, originates from a neural stem cell (NSC) located in the subventricular zone (SVZ) of the lateral cerebral ventricle. Using the most advanced in vivo imaging techniques, Gengatharan and colleagues recently identified a day/night difference in the adult SVZ-NSC division. They reported that the circadian melatonin rhythm and its receptor control the day/night difference in NSC division with high mitotic activity during the day and low activity at night. Expression of melatonin and its receptor diminishes during agei…

Novel melatonin-trientine conjugate as potential therapeutic agents for Alzheimer's disease.

Researchers continue to explore drug targets to treat the characteristic pathologies of Alzheimer's disease (AD). Some drugs relieve the pathological processes of AD to some extent, but the failed clinical trials indicate that multifunctional agents seem more likely to achieve the therapy goals for this neurodegenerative disease. Herein, a novel compound named melatonin-trientine (TM) has been covalently synthesized with the natural antioxidant compounds melatonin and the metal ion chelator trientine. After toxicological and pharmacokinetic verification, we elucidated the effects of intraperit…

Perioperative melatonin in COVID-19 patients: benefits beyond sedation and analgesia.

Cytokine storm in coronavirus disease 2019 (COVID-19) patients leads to acute lung injury, acute respiratory distress syndrome, multiorgan dysfunction, shock, and thrombosis thus contributing to significant morbidity and mortality. Several agents like steroids, ascorbic acid, vitamins (C, D, E), glutathione, N-acetylcysteine have been used and several studies are underway to identify its efficacy in addressing undesirable effects due to COVID-19 illness. Among several experimental modalities based on expert opinion and anecdotal data, melatonin is one molecule that appears promising. Owing to …

Melatonin ameliorates renal dysfunction in glyphosate- and hard water-treated mice.

Chronic interstitial nephritis in agricultural communities (CINAC) is a severe and widespread disease that has been associated with environmental and occupational exposure to glyphosate and hard water. However, the potential underlying mechanisms remain incompletely understood. Melatonin is reported to exert protective effects on the kidney, but whether melatonin can attenuate renal tubular injury in mice exposed to glyphosate combined with hard water is unclear. Here, mice were treated with high doses and environmentally relevant doses of glyphosate (100 mg/kg·bw and 0.7 mg/L, respectively) a…

Melatonin decreases androgen-sensitive prostate cancer growth by suppressing SENP1 expression.

BACKGROUND: Melatonin is a hormone naturally produced by the pineal gland in the brain. In addition to modulating circadian rhythms, it has pleiotropic biological effects including antioxidant, immunomodulatory, and anti-cancer effects. Herein, we report that melatonin has the ability to decrease the growth and metastasis of androgen-dependent prostate cancer. METHODS: To evaluate the anti-cancer effect of melatonin on androgen-sensitive prostate cancer in vitro or in vivo, the effects of cell proliferation, apoptosis, migration and invasion were analyzed by using 3-(4,5-dimethylthiazol-2-yl)…