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1.
Biochim Biophys Acta Mol Basis Dis ; 1868(1): 166281, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610472

RESUMO

Colorectal cancer (CRC) is one of the most common gastrointestinal malignancies. The occurrence and development of CRC are complicated processes. Obesity and dysbacteriosis have been increasingly regarded as the main risk factors for CRC. Understanding the etiology of CRC from multiple perspectives is conducive to screening for some potential drugs or new treatment strategies to limit the serious side effects of conventional treatment and prolong the survival of CRC patients. Melatonin, a natural indoleamine, is mainly produced by the pineal gland, but it is also abundant in other tissues, including the gastrointestinal tract, retina, testes, lymphocytes, and Harder's glands. Melatonin could participate in lipid metabolism by regulating adipogenesis and lipolysis. Additionally, many studies have focused on the potential beneficial effects of melatonin in CRC, such as promotion of apoptosis; inhibition of cell proliferation, migration, and invasion; antioxidant activity; and immune regulation. Meaningfully, gut microbiota is the main determinant of all aspects of health and disease (including obesity and tumorigenesis). The gut microbiota is of great significance for understanding the relationship between obesity and increased risk of CRC. Although the current understanding of how the melatonin-mediated gut microbiota coordinates a variety of physiological and pathological activities is fairly comprehensive, there are still many unknown topics to be explored in the face of a complex nutritional status and a changeable microbiota. This review summarizes the potential links among melatonin, lipid metabolism, gut microbiota, and CRC to promote the development of melatonin as a preventive and therapeutic agent for CRC.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Melatonina/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia
2.
Theriogenology ; 177: 1-10, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653791

RESUMO

Chloroquine (CQ) could function as a lysosomotropic agent to inhibit the endolysosomal trafficking in the autophagy pathway, and is widely used on malarial, tumor and recently COVID-19. However, the effect of CQ treatment on porcine immature Sertoli cells (iSCs) remains unclear. Here we showed that CQ could reduce iSC viability in a dose-dependent manner. CQ treatment (20 µM) on iSCs for 36h could elevate oxidative stress, damage mitochondrial function and promote apoptosis, which could be partially rescued by melatonin (MT) (10 nM). Transcriptome profiling identified 1611 differentially expressed genes (DEGs) (776 up- and 835 down-regulated) (20 µM CQ vs. DMSO), mainly involved in MAPK cascade, cell proliferation/apoptosis, HIF-1, PI3K-Akt and lysosome signaling pathways. In contrast, only 467 (224 up- and 243 down-regulated) DEGs (CQ + MT vs. DMSO) could be found after MT (10 nM) addition, enriched in cell cycle, regulation of apoptotic process, lysosome and reproduction pathways. Therefore, the partial rescue effects of MT on CQ treatment were confirmed by multiple assays (cell viability, ROS level, mitochondrial function, apoptosis, and mRNA levels of selected genes). Collectively, CQ treatment could impair porcine iSC viability by deranging the signaling pathways related to apoptosis and autophagy, which could be partially rescued by MT supplementation.


Assuntos
COVID-19 , Melatonina , Doenças dos Suínos , Animais , Apoptose , Autofagia , COVID-19/tratamento farmacológico , COVID-19/veterinária , Cloroquina/farmacologia , Masculino , Melatonina/farmacologia , Fosfatidilinositol 3-Quinases , SARS-CoV-2 , Células de Sertoli , Suínos
3.
Med Gas Res ; 12(2): 41-43, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34677150

RESUMO

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 its anti-inflammatory, anti-oxidant, and immunomodulatory properties, melatonin can be an important agent used as a component of multimodal analgesia in COVID-19 patients, suspected patients, and patients with exposure to positive patients undergoing emergency or urgent surgeries. Further research is required to know the optimal time of initiation, dose, and duration of melatonin as an adjunct.


Assuntos
Analgesia , COVID-19 , Melatonina , Síndrome da Liberação de Citocina , Humanos , Melatonina/uso terapêutico , SARS-CoV-2
4.
Environ Pollut ; 292(Pt B): 118445, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34737029

RESUMO

Decabromodiphenyl ethane (DBDPE) is a novel flame retardant that is widely used in plastics, electronic products, building materials and textiles. Our previous studies have revealed the oocyte toxicity of DBDPE, but the effect of DBDPE on preimplantation embryo development has not been reported. Here, we investigated whether and how DBDPE exposure affects preimplantation embryo development. Adult female mice were orally exposed to DBDPE (0, 5, 50, 500 µg/kg bw/day) for 14 days. First, we found that after DBDPE exposure, mice showed obvious circadian rhythm disorder. Moreover, the development of preimplantation embryos was inhibited in DBDPE-exposed mice after pregnancy. Then, we further explored and revealed that DBDPE exposure reduced the endogenous melatonin (MLT) level during pregnancy, thereby inhibiting the development of preimplantation embryos. Furthermore, we discovered that exogenous MLT supplementation (15 mg/kg bw/day) rescued the inhibition of preimplantation embryo development induced by DBDPE, and a mechanistic study demonstrated that exogenous MLT inhibited the overexpression of ROS and DNA methylation at the 5-position of cytosine (5-mC) in DBDPE-exposed preimplantation embryos. Simultaneously, MLT ameliorated the DBDPE-induced mitochondrial dysfunction by increasing the mitochondrial membrane potential (MMP), ATP, and Trp1 expression. Additionally, MLT restored DBDPE-induced changes in zona pellucida (ZP) hardness and trophectoderm (TE) cortical tension. Finally, the protective effect of MLT on embryos ameliorated the adverse reproductive outcomes (dead fetus, fetus with abnormal liver, fetal weight loss) induced by DBDPE. Collectively, DBDPE induced preimplantation embryo damage leading to adverse reproductive outcomes, and MLT has emerged as a potential tool to rescue adverse reproductive outcomes induced by DBDPE.


Assuntos
Transtornos Cronobiológicos , Melatonina , Animais , Bromobenzenos , Ritmo Circadiano , Desenvolvimento Embrionário , Feminino , Camundongos
5.
Environ Pollut ; 292(Pt B): 118473, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758366

RESUMO

Melatonin (MT) and selenium (Se) application known to decrease heavy metal uptake and toxicity in plants. By mixing the Se in MT medium a new complex MT-Se nanoparticles (MT-Se NPs) was synthesized and we investigated the role of MT-Se NPs on B. napus growth and tolerance against As stress. The MT-Se particles significantly enhanced the plant growth and other associated physiological attributes under As stress. The As treatment at 80 µM was more phytotoxic, however MT-Se NPs application resulted in a substantial increase in leaf chlorophyll fluorescence, biomass accumulation, and decreased ROS relative to As stressed plants. The use of MT-Se NPs to As stressed plants reduced photosynthetic inhibition and oxidative stress and attenuated the increase in MDA and H2O2 contents. The application of MT-Se NPs also boosted the antioxidant enzymes activities such as SOD, POD and CAT as well as the APX, GR and GSH activates under As stress. The results also showed MT-Se NPs treatments alleviated the growth inhibition induced by As and reduced the accumulation of As in leaves and roots of B. napus seedlings. Moreover, treatment with MT-Se NPs improved the plant growth more successfully than treatment of MT and Se alone. This study explored the mechanism of melatonin and selenium efficiency in the composition can be jointly encouraged to exert synergistic effects and boost plant enzymatic activities.


Assuntos
Arsênio , Brassica napus , Melatonina , Nanopartículas , Selênio , Arsênio/toxicidade , Peróxido de Hidrogênio
6.
Appl Ergon ; 99: 103618, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34775135

RESUMO

It is well known that exposure to light at the right time of the day is important to synchronise our circadian rhythm and enhance cognitive functioning. There is, however, a lack of field studies investigating which lighting characteristics are necessary to improve sleep and cognitive functioning. A controlled field study with 80 shift workers was set up, in which the impact of an integrative lighting (IL) scenario was investigated during the morning shift. Two groups were compared: a control group (no change in lighting settings) and a IL-group (exposed to a melanopic Equivalent Daylight Illuminance of 192 lux, i.e., bright light with a high fraction of short-wavelengths). Pre-post measurement of visual comfort, cognitive functioning (D2 task, go-nogo reaction time task) and sleep (MotionWatch8) were performed. The IL-settings ameliorated sleep efficiency and sleep latency during morning shift and enhanced alertness (not inhibition) compared to standard lighting conditions. Changing lighting settings in an industrial setting should be considered as it seems worthwhile for employees' sleep and cognitive performance.


Assuntos
Iluminação , Melatonina , Atenção , Ritmo Circadiano , Cognição , Humanos , Luz , Sono
7.
J Med Virol ; 94(1): 263-271, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34460132

RESUMO

This trial aims to evaluate the effectiveness of adding melatonin to the treatment protocol of hospitalized coronavirus disease 2019 (COVID-19) patients. This was an open-label, randomized controlled clinical trial in hospitalized COVID-19 patients. Patients were randomized into a treatment arm receiving melatonin plus standard care or a control arm receiving standard care alone. The trial's primary endpoint was sleep quality examined by the Leeds Sleep Evaluation Questionnaire (LSEQ). The trial's secondary endpoints were symptoms alleviation by Day 7, intensive care unit admission, 10-day mortality, white blood cell count, lymphocyte count, C-reactive protein status, and peripheral capillary oxygen saturation. Ninety-six patients were recruited and allocated to either the melatonin arm (n = 48) or control arm (n = 48). Baseline characteristics were similar across treatment arms. There was no significant difference in symptoms on Day 7. The mean of the LSEQ scores was significantly higher in the melatonin group (p < 0.001). There was no significant difference in laboratory data, except for blood oxygen saturation, which has improved significantly in the melatonin group compared with the control group (95.81% vs. 93.65% respectively, p = 0.003). This clinical trial study showed that the combination of oral melatonin tablets and standard treatment could substantially improve sleep quality and blood oxygen saturation in hospitalized COVID-19 patients.


Assuntos
COVID-19/tratamento farmacológico , COVID-19/fisiopatologia , Melatonina/uso terapêutico , Sono/efeitos dos fármacos , Feminino , Hospitalização , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue
8.
Sci Total Environ ; 806(Pt 4): 150918, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653461

RESUMO

Light pollution is a global environmental issue that affects photosensitive organisms. For instance, several researchers have recognized melatonin suppression in humans as a direct cause of long-term exposure to high artificial light levels at night. Others have identified low melatonin levels as a risk factor for a higher prevalence of hormone-sensitive cancer. This paper analyzes the association between light pollution, estimated as the emission analysis of satellite worldwide nighttime light collections from 1999 to 2012, and 25,025 breast and 16,119 prostate cancer events from 2003 to 2012. Both types of cancer increased during the study period, but light pollution increased in urban and peri-urban areas and decreased in rural areas. Cumulative light pollution during 5 years showed a positive association with breast cancer but not with prostate cancer. The association between light pollution and breast cancer persisted when adjusted to age-standardized rates with a mean increase of 10.9 events per 100,000 population-year (95% confidence interval 7.0 to 14.8). We conclude that exposure to elevated light pollution levels could be a risk factor for breast cancer in Slovakia. This work can interest researchers who study relationships between atmospheric pollutants and the growing cancer epidemic. The results and the methodology can be extrapolated to any country in the world if data is available.


Assuntos
Melatonina , Neoplasias da Próstata , Humanos , Masculino , Prevalência , Neoplasias da Próstata/epidemiologia , Fatores de Risco
9.
J Hazard Mater ; 423(Pt B): 127159, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34537633

RESUMO

Melatonin, a regulatory molecule, performs pleiotropic functions in plants, including aluminum (Al) stress mitigation. Here, we conducted transcriptomic and physiological analyses to identify metabolic processes associated with the alleviated Al-induced growth inhibition of the melatonin-treated (MT) maize (Zea mays L.) seedlings. Melatonin decreased Al concentration in maize roots and leaves under Al stress. Al stress reduced the total dry weight (DW) by 41.2% after 7 days of treatment. By contrast, the total DW was decreased by only 19.4% in MT plants. According to RNA-Seq, enzyme activity, and metabolite content data, MT plants exhibited a higher level of relatively stable carbon and nitrogen metabolism than non-treated (NT) plants. Under Al stress, MT plants showed higher photosynthetic rate and sucrose content by 29.9% and 20.5% than NT plants, respectively. Similarly, the nitrate reductase activity and protein content of MT plants were 34.0% and 15.0% higher than those of NT plants, respectively. Furthermore, exogenous supply of melatonin mitigated Al-induced oxidative stress. Overall, our results suggest that melatonin alleviates aluminum-induced growth inhibition through modulating carbon and nitrogen metabolism, and reestablishing redox homeostasis in maize. Graphical Abstarct.


Assuntos
Melatonina , Alumínio/toxicidade , Carbono , Homeostase , Melatonina/farmacologia , Nitrogênio , Oxirredução , Plântula , Zea mays/genética
10.
J Hazard Mater ; 424(Pt A): 127265, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34583160

RESUMO

Nitrogen dioxide (NO2) is a common outdoor air pollutant, which has adverse effects on the environment and human health. Herein, NO2 inhibited photosynthesis and antioxidant capacity in plants. Melatonin (Mel) is a neurohormone found in the pineal gland. Exogenous Mel alleviated chlorophyll degradation and increased the expression of key proteins and genes in the process of chlorophyll synthesis in tobacco leaves exposed to NO2. Additionally, the activities of photosystem II (PSII) and photosystem I (PSI) were enhanced. PSII and PSI reaction center proteins and genes were upregulated. Mel pre-treatment enhanced enzyme activities and expression of proteins related to the ascorbic acid-glutathione cycle and thioredoxin-peroxiredoxin pathway in leaves exposed to NO2, thus regulating their redox balance. Furthermore, exogenous Mel mediated the polyamine synthesis pathway and increased the expression of the key enzyme proteins SAMS1, SAMS2, and SAMS3 in the polyamine synthesis pathway in leaves under NO2 stress. Mel regulated ABA signal transduction and calmodulin binding transcription factors CAMTA12 and NtCaM calmodulin NtCaM2 in Ca2+ signal transduction. Collectively, these results elucidate that Mel can alleviate high-concentration NO2, thus suitable for agricultural application.


Assuntos
Melatonina , Tabaco , Antioxidantes , Clorofila , Transporte de Elétrons , Homeostase , Humanos , Dióxido de Nitrogênio/toxicidade , Oxirredução , Fotossíntese , Folhas de Planta , Transdução de Sinais
11.
PLoS One ; 16(12): e0261305, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34928967

RESUMO

BACKGROUND: The clinical effect of enteral administration of sleep-promoting medication (SPM) in mechanically ventilated patients remains unclear. This study aimed to investigate the relationship between enteral SPM administration and the intravenous sedative dose and examine the safety and cost of enteral SPM administration. METHODS: This single-center retrospective cohort study was conducted in a Japanese tertiary hospital intensive care unit (ICU). The exposure was enteral SPM administration during mechanical ventilation. The outcome was the average daily propofol dose per body weight administered as a continuous sedative during mechanical ventilation. Patients were divided into three groups based on the timing of SPM administration at ICU admission: "administration within 48 hours (early administration [EA])," "administration after 48 hours (late administration [LA])," and "no administration (NA)." We used multiple linear regression models. RESULTS: Of 123 included patients, 37, 50, and 36 patients were assigned to the EA, LA, and NA groups, respectively. The average daily propofol dose per body weight was significantly lower in the EA group than in the LA and NA groups (ß -5.13 [95% confidence interval (CI) -8.93 to -1.33] and ß -4.51 [95% CI -8.59 to -0.43], respectively). Regarding safety, enteral SPM administration did not increase adverse events, including self-extubation. The total cost of neuroactive drugs tended to be lower in the EA group than in the LA and NA groups. CONCLUSIONS: Early enteral SPM administration reduced the average daily propofol dose per body weight without increasing adverse events.


Assuntos
Nutrição Enteral/métodos , Hipnóticos e Sedativos/administração & dosagem , Indenos/administração & dosagem , Melatonina/administração & dosagem , Propofol/administração & dosagem , Respiração Artificial/métodos , Sono/efeitos dos fármacos , Administração Intravenosa , Idoso , Depressores do Sistema Nervoso Central/administração & dosagem , Feminino , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(12): 1262-1265, 2021 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-34839521

RESUMO

Smith-Magenis syndrome (SMS) (OMIM #182290) is a rare genetic disorder with a prevalence of 1 in 25 000 live births. Approximately 90% of SMS patients have harbored a 3.7 Mb interstitial 17p11.2 deletion involving the RAI1 gene, while 10% of cases have carried pathogenic variants of the RAI1 gene. SMS is characterized by sleep disturbance, intellectual impairment, developmental delay, craniofacial and cardiovascular anomalies, obesity, self injury, aggressive and autistic-like behaviors. Most SMS patients have sleep disorders such as short total sleep time, frequent night waking, short sleep onset, and early morning waking. The sleep disturbance may aggravate with age and persist throughout life. Three mechanisms have been delineated. The first concern was the abnormal secretion of melatonin, with high levels during daytime and low levels at night. Evaluation of the integrity of the intrinsically photosensitive retinal ganglion cell (ipRGC)/melanopsin system has found that SMS patients showed dysfunction in the sustained component of the pupillary light responses to blue light. Synchronization of daily melatonin profile and its photoinhibition are dependent on the activation of melanopsin. Dysfunction of the retina-melanin system may be one of the causes of melatonin spectrum disorders. Secondly, dysregulation of circadian rhythm gene expression has also been noted in mice and SMS patients. Finally, there may be association between sleep deprivation symptoms and DNA methylation patterns, which has provided new insights for SMS-associated sleep disorders and symptoms alike. Treatment for SMS-related sleep disorders is administered primarily through medications like melatonin tablets, which can alleviate insomnia-related sleep difficulties, in particular externalizing behavior in children. Researchers are also actively exploring other treatments for SMS currently.


Assuntos
Melatonina , Transtornos do Sono-Vigília , Síndrome de Smith-Magenis , Animais , Ritmo Circadiano , Humanos , Camundongos , Sono , Transtornos do Sono-Vigília/genética , Síndrome de Smith-Magenis/genética
13.
Plant Sci ; 313: 111093, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34763877

RESUMO

Although several studies have confirmed that exogenous melatonin promotes anthocyanin accumulation, the molecular mechanism of this remains elusive. Here, the signaling cross-talk between melatonin and NADPH oxidase (RBOH) -mediated ROS during anthocyanin biosynthesis were investigated. We found that application of exogenous melatonin not only induced anthocyanin biosynthesis, but also increased endogenous H2O2 and O2‾ content in pear fruits. The effect of melatonin on anthocyanin biosynthesis was abolished by inhibitors of RBOH. We also observed that genes encoding RBOH (PuRBOHF) were ubiquitously and highly expressed after melatonin treatment. Transient PuRBOHF overexpression significantly enhanced anthocyanin accumulation and activated transcription of anthocyanin biosynthesis genes, whereas PuRBOHF silencing repressed melatonin-promoted anthocyanin accumulation and H2O2 production. Moreover, RBOH-derived H2O2 induced PuMYB10 transcription, and PuRBOHF enhanced the PuMYB10-induced activation of the PuUFGT promoter. PuMYB10, in turn, activated PuRBOHF transcription, revealing a positive feedback loop. These results provide molecular evidence supporting the essential roles of PuRBOHF-dependent H2O2 in melatonin-induced anthocyanin accumulation in pears.


Assuntos
Antocianinas/biossíntese , Peróxido de Hidrogênio/metabolismo , Melatonina/metabolismo , Pyrus/genética , Pyrus/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/efeitos dos fármacos , Antocianinas/genética , China , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Melatonina/genética
14.
Adv Exp Med Biol ; 1344: 153-168, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34773231

RESUMO

Altered behavioral rhythms are a fundamental diagnostic feature of mood disorders. Patients report worse subjective sleep and objective measures confirm this, implicating a role for circadian rhythm disruptions in mood disorder pathophysiology. Molecular clock gene mutations are associated with increased risk of mood disorder diagnosis and/or severity of symptoms, and mouse models of clock gene mutations have abnormal mood-related behaviors. The mechanism by which circadian rhythms contribute to mood disorders remains unknown, however, circadian rhythms regulate and are regulated by various biological systems that are abnormal in mood disorders and this interaction is theorized to be a key component of mood disorder pathophysiology. A growing body of evidence has begun defining how the interaction of circadian and neurotransmitter systems influences mood and behavior, including the role of current antidepressants and mood stabilizers. Additionally, the hypothalamus-pituitary-adrenal (HPA) axis interacts with both circadian and monoaminergic systems and may facilitate the contribution of environmental stressors to mood disorder pathophysiology. The central role of circadian rhythms in mood disorders has led to the development of chronotherapeutics, which are treatments designed specifically to target circadian rhythm regulators, such as sleep, light, and melatonin, to produce an antidepressant response.


Assuntos
Ritmo Circadiano , Melatonina , Animais , Humanos , Melatonina/uso terapêutico , Camundongos , Transtornos do Humor/tratamento farmacológico , Transtornos do Humor/genética , Sistema Hipófise-Suprarrenal , Sono
15.
Wiad Lek ; 74(9 cz 1): 2202-2206, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34725301

RESUMO

OBJECTIVE: The aim: To find out density of melatonin receptors 1A in the neurons of the lateral preoptic nucleus of the hypothalamus in mature and old rats under various light conditions. PATIENTS AND METHODS: Materials and methods: The study was carried out on 72 albino mature and old rats with light conditions appropriate for the experiment. To find out circadian differences of melatonin receptors 1A the material for the study was taken at 2 p.m. and 2 a.m. Visualization of primary antibodies against melatonin receptors 1A (Abcam) was conducted by means of the polymeric system Dako and diaminobenzidine staining under the microscope Delta Optical Evolution 100. The intensity of staining was assessed on the digital copies of images according to computer microdensitometry method. RESULTS: Results: Immunohistochemical examinations conducted enable to suggest that melatonin receptors 1A in the neurons of the lateral preoptic nucleus of the hypothalamus respond to different light conditions. In particular, intensity of immunohistochemical staining to melatonin receptors 1A under conditions of light deprivation increases both in mature and old rats, but it decreases under conditions of light stimulation. The parameter is higher at 2 a.m. as compared with 2 p.m. Intensity of immunohistochemical staining to melatonin receptors 1A in the neurons of the lateral preoptic nucleus of the hypothalamus is always lower in old rats than in mature ones. CONCLUSION: Conclusions: Density of melatonin receptors 1A in the neurons of the lateral preoptic nucleus of the hypothalamus is subordinated to the circadian rhythm: it increases at night and decreases in the daytime. At the same time, light stimulation results in disorders of the rhythm and development of desynchronization.


Assuntos
Melatonina , Área Pré-Óptica , Animais , Ritmo Circadiano , Hipotálamo , Ratos , Receptores de Melatonina
16.
Nurs Clin North Am ; 56(4): 565-572, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34749895

RESUMO

Sleep is often misunderstood in its impact on many chronic diseases including obesity. Obesity and restorative sleep are intertwined processes. Poor sleep negatively affects the key hormones of weight and appetite regulation, thereby potentially increasing weight via mechanisms that increase hunger and lower metabolism, thereby making the successful treatment of obesity more difficult. Clinicians should consider a comprehensive sleep history and proper treatment or referral to a sleep specialist in conjunction with obesity treatment. Adequate restorative sleep is integral to a comprehensive obesity treatment program.


Assuntos
Obesidade/fisiopatologia , Privação do Sono/fisiopatologia , Sono/fisiologia , Apetite/fisiologia , Grelina , Humanos , Leptina/sangue , Melatonina/administração & dosagem , Estresse Psicológico/psicologia
17.
Biol Res ; 54(1): 36, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736526

RESUMO

BACKGROUND: Melatonin 2-hydroxylase (M2H) is the first enzyme in the catabolism pathway of melatonin, which catalyzes the production of 2-hydroxymelatonin (2-OHM) from melatonin. The content of 2-hydroxymelatonin in plants is much higher than that of melatonin. So M2H may be a key enzyme in the metabolic pathway of melatonin. METHOD: We conducted a systematic analysis of the M2H gene family in Gossypium hirsutum based on the whole genome sequence by integrating the structural characteristics, phylogenetic relationships, expression profile, and biological stress of the members of the Gossypium hirsutum M2H gene family. RESULT: We identified 265 M2H genes in the whole genome of Gossypium hirsutum, which were divided into 7 clades (clades I-VII) according to phylogenetic analysis. Most M2H members in each group had similar motif composition and gene structure characteristics. More than half of GhM2H members contain ABA-responsive elements and MeJA-responsive elements. Under different stress conditions, the expression levels of the gene changed, indicating that GhM2H members were involved in the regulation of abiotic stress. Some genes in the GhM2H family were involved in regulating melatonin levels in cotton under salt stress, and some genes were regulated by exogenous melatonin. CONCLUSION: This study is helpful to explore the function of GhM2H, the downstream metabolism gene of melatonin in cotton, and lay the foundation for better exploring the molecular mechanism of melatonin improving cotton's response to abiotic stress.


Assuntos
Gossypium , Melatonina , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
18.
J Contemp Dent Pract ; 22(7): 739-744, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34615777

RESUMO

AIM AND OBJECTIVE: To histologically compare alveolar bone repair after tooth extraction treated with melatonin and calcium sulfate in an in vivo experimental study in guinea pigs (Cavia porcellus). MATERIALS AND METHODS: The study was of longitudinal, prospective, and experimental design in an animal bio-model. A total of 24 male guinea pigs were included, weighing from 700 to 900 g and separated into two experimental groups (melatonin and calcium sulfate) for three periods (15, 30, and 45 days) at 15-day intervals after surgery. The guinea pigs were randomly included into groups for the time evaluated. RESULTS: In relation to bone repair cells using calcium sulfate, the presence of osteoblasts at 15, 30, and 45 days was 39.0 ± 63, 55.3 ± 6.0, respectively, with 61.3 ± 10.0 cells per field. Regarding bone repair cells using melatonin, the presence of osteoblasts at 15, 30, and 45 days was 25.0 ± 3.7, 49.3 ± 1.5, respectively, with 53.6 ± 5.6 cells per field. CONCLUSION: Both melatonin and calcium sulfate were found to be useful in bone repair at a histological and clinical level, although they present certain nonsignificant, albeit marked advantages in the bone repair process when compared with the control socket at the histological level. CLINICAL SIGNIFICANCE: This research allows us to know the usefulness of these easily accessible chemicals for the generation of bone repair.


Assuntos
Sulfato de Cálcio , Melatonina , Animais , Cobaias , Masculino , Melatonina/farmacologia , Estudos Prospectivos , Projetos de Pesquisa
19.
Molecules ; 26(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34641628

RESUMO

This work aims to assess the recently established anti-inflammatory and antioxidant potential of melatonin of plant origin extracted from the plant matrix as a phytomelatonin complex (PHT-MLT), and compare its activity with synthetic melatonin (SNT-MLT) when used on its own or with vitamin C. For this purpose, a COX-2 enzyme inhibitory activity test, an antiradical activity in vitro and on cell lines assays, was performed on both PHT-MLT and SNT-MLT products. COX-2 inhibitory activity of PHT-MLT was found to be ca. 6.5 times stronger than that of SNT-MLT (43.3% and 6.7% enzyme inhibition, equivalent to the activity of acetylsalicylic acid in conc. 30.3 ± 0.2 and 12.0 ± 0.3 mg/mL, respectively). Higher antiradical potential and COX-2 inhibitory properties of PHT-MLT could be explained by the presence of additional naturally occurring constituents in alfalfa, chlorella, and rice, which were clearly visible on the HPLC-ESI-QTOF-MS fingerprint. The antiradical properties of PHT-MLT determined in the DPPH test (IC50 of 21.6 ± 1 mg of powder/mL) were found to originate from the presence of other metabolites in the 50% EtOH extract while SNT-MLT was found to be inactive under the applied testing conditions. However, the antioxidant studies on HaCaT keratinocytes stimulated with H2O2 revealed a noticeable activity in all samples. The presence of PHT-MLT (12.5, 25 and 50 µg/mL) and vitamin C (12.5, 25 and 50 µg/mL) in the H2O2-pretreated HaCaT keratinocytes protected the cells from generating reactive oxygen species. This observation confirms that MLT-containing samples affect the intracellular production of enzymes and neutralize the free radicals. Presented results indicated that MLT-containing products in combination with Vitamin C dosage are worth to be considered as a preventive alternative in the therapy of various diseases in the etiopathogenesis, of which radical and inflammatory mechanisms play an important role.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Ciclo-Oxigenase 2/metabolismo , Queratinócitos/citologia , Melatonina/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Antioxidantes/síntese química , Antioxidantes/química , Ácido Ascórbico/farmacologia , Linhagem Celular , Regulação para Baixo , Sinergismo Farmacológico , Radicais Livres/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/efeitos adversos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Melatonina/síntese química , Melatonina/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
20.
Int J Mol Sci ; 22(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34639101

RESUMO

A well-functional intestinal mucosal barrier can be compromised as a result of various diseases, chemotherapy, radiation, and chemical exposures including surfactants. Currently, there are no approved drugs targeting a dysfunctional intestinal barrier, which emphasizes a significant medical need. One candidate drug reported to regulate intestinal mucosal permeability is melatonin. However, it is still unclear if its effect is primarily receptor mediated or antioxidative, and if it is associated with enteric neural pathways. The aim of this rat intestinal perfusion study was to investigate the mechanisms of melatonin and nicotinic acetylcholine receptors on the increase in intestinal mucosal clearance of 51Cr-labeled ethylenediaminetetraacetate induced by 15 min luminal exposure to the anionic surfactant, sodium dodecyl sulfate. Our results show that melatonin abolished the surfactant-induced increase in intestinal permeability and that this effect was inhibited by luzindole, a melatonin receptor antagonist. In addition, mecamylamine, an antagonist of nicotinic acetylcholine receptors, reduced the surfactant-induced increase in mucosal permeability, using a signaling pathway not influenced by melatonin receptor activation. In conclusion, our results support melatonin as a potentially potent candidate for the oral treatment of a compromised intestinal mucosal barrier, and that its protective effect is primarily receptor-mediated.


Assuntos
Permeabilidade da Membrana Celular , Mucosa Intestinal/efeitos dos fármacos , Doenças do Jejuno/prevenção & controle , Jejuno/efeitos dos fármacos , Melatonina/farmacologia , Receptores de Melatonina/metabolismo , Tensoativos/toxicidade , Animais , Antioxidantes/farmacologia , Motilidade Gastrointestinal , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Doenças do Jejuno/induzido quimicamente , Doenças do Jejuno/metabolismo , Doenças do Jejuno/patologia , Jejuno/metabolismo , Jejuno/patologia , Masculino , Ratos , Ratos Wistar , Receptores de Melatonina/genética , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo
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