Therapeutic potential of stem cell and melatonin on the reduction of CCl4-induced liver fibrosis in experimental mice model / Potencial terapêutico de células-tronco e melatonina na redução da fibrose hepática induzida por CCl4 no modelo de ratos experimentais

Liver fibrosis is initial stage of any chronic liver disease and its end stage is develops into cirrhosis. Chronic liver diseases are a crucial global health issue and the cause of approximately 2 million deaths per year worldwide. Cirrhosis is currently the 11th most common cause of death globally. Mesenchymal stem cell (MSCs) treatment is the best way to treat acute and chronic liver disease. The aim of this study is to improve the therapeutic potential of MSCs combined with melatonin (MLT) to overcome CCl4-induced liver fibrosis and also investigate the individual impact of melatonin and MSCs against CCl4-induced liver impairment in animal model. Female BALB/c mice were used as CCL4-induced liver fibrotic animal model. Five groups of animal model were made; negative control, Positive control, CCl4+MSCs treated group, CCl4+MLT treated group and CCl4+MSCs+MLT treated group. Cultured MSCs from mice bone marrow were transplanted to CCl4-induced liver injured mice model, individually as well as together with melatonin. Two weeks after MSCs and MLT administration, all groups of mice were sacrificed for examination. Morphological and Histopathological results showed that combined therapy of MSCs+MLT showed substantial beneficial impact on CCl4-induced liver injured model, compared with MSCs and MLT individually. Biochemically, considerable reduction was observed in serum bilirubin and ALT levels of MLT+MSC treated mice, compared to other groups. PCR results shown down-regulation of Bax and up-regulation of Bcl-xl and Albumin, confirm a significant therapeutic effect of MSCs+MLT on CCI4-induced liver fibrosis. From the results, it is concluded that combined therapy of MSCs and MLT show strong therapeutic effect on CCL4-induced liver fibrosis, compared with MSCs and MLT individually.

A fibrose hepática é a fase inicial de qualquer doença hepática crônica, e em sua fase final desenvolve-se para cirrose. As doenças hepáticas crônicas são uma questão de saúde global crucial e a causa de aproximadamente 2 milhões de mortes por ano em todo o mundo. A cirrose, hoje em dia, é a 11ª causa mais comum de morte globalmente. O tratamento da célula-tronco mesenquimal (MSCs) é uma maneira eletiva de tratar a doença hepática aguda e crônica. O objetivo deste estudo é melhorar o potencial terapêutico dos MSCs combinados com a melatonina (MLT) para superar a fibrose hepática induzida por CCl4 e também investigar o impacto individual da melatonina e MSCs contra o comprometimento do fígado induzido por CCl4 no modelo animal. Os ratos BALB / C fêmeas foram usados ​​como modelo de animal fibrótico de fígado induzido por CCl4. Cinco grupos de modelo animal foram feitos: Controle Negativo, Controle Positivo, CCl4 + MSCs Tratados Grupo, Grupo Tratado CCl4 + MLT e Grupo Tratado CCl4 + MSCs + MLT. MSCs cultivados da medula óssea dos ratos foram transplantados para o modelo de camundongos de fígado induzido por CCl4, individualmente, bem como em conjunto com a melatonina. Duas semanas após a administração MSCs e MLT, todos os grupos de camundongos foram sacrificados para o exame. Os resultados morfológicos e histopatológicos mostraram que a terapia combinada do MSCs + MLT mostrou impacto benéfico substancial no modelo ferido no fígado induzido pelo CCl4, em comparação com o MSCs e o MLT individualmente. A redução bioquimicamente considerável foi observada em bilirrubina sérica e níveis ALT de ratinhos tratados com MLT + MSCs, em comparação com outros grupos. Os resultados de PCR mostraram regulação negativa do BAX e regulação positiva do BCL-XL e da albumina, confirmando um efeito terapêutico significativo do MSCs + MLT na fibrose hepática induzida por CCl4. Dos resultados, conclui-se que a terapia combinada de MSCs e MLT mostram um forte efeito terapêutico na fibrose hepática induzida por CCl4, em comparação com MSCs e MLT individualmente.

A rapid and sensitive High-Performance Liquid Chromatography method with fluorescence detection for quantification of melatonin in small volume rat plasma samples: application to a preclinical study to determine the oral pharmacokinetics of melatonin under gestational conditions

Abstract A novel, simple and sensitive high-performance liquid chromatography with fluorescence detection method was developed and validated for the characterization of the preclinical pharmacokinetics of melatonin under pregnant conditions. Plasma samples (25 µL) were treated with 30 µL of ethanol absolute (containing the internal standard, IS). After a centrifugation process, aliquots of supernant (5 µL) were injected into the chromatographic system. Compounds were eluted on a Xbridge C18 (150 mm x 4.6 mm i.d., 5 µm particle size) maintained at 30°C. The mobile phase consisted in a mixture of aqueous solution of 0.4% phosphoric acid and acetonitrile (70:30 v/v). The wavelengths were set at 305 nm (excitation) and 408 nm (emission) and the total analysis time was 8 min/sample. All validation tests were obtained with accuracy and precision, according to FDA guidelines, over the concentration range of 0.005-20 µg/mL. Pharmacokinetic study showed that melatonin systemic exposure increased from day 14, with a significant difference at 19 days of gestation compared to the control group. Our findings suggest a decreased metabolism of melatonin as result of temporary physiological changes that occur throughout pregnancy. However, other maternal physiological changes cannot be ruled out.

Therapeutic potential of stem cell and melatonin on the reduction of CCl4-induced liver fibrosis in experimental mice model

Abstract Liver fibrosis is initial stage of any chronic liver disease and its end stage is develops into cirrhosis. Chronic liver diseases are a crucial global health issue and the cause of approximately 2 million deaths per year worldwide. Cirrhosis is currently the 11th most common cause of death globally. Mesenchymal stem cell (MSCs) treatment is the best way to treat acute and chronic liver disease. The aim of this study is to improve the therapeutic potential of MSCs combined with melatonin (MLT) to overcome CCl4-induced liver fibrosis and also investigate the individual impact of melatonin and MSCs against CCl4-induced liver impairment in animal model. Female BALB/c mice were used as CCL4-induced liver fibrotic animal model. Five groups of animal model were made; negative control, Positive control, CCl4+MSCs treated group, CCl4+MLT treated group and CCl4+MSCs+MLT treated group. Cultured MSCs from mice bone marrow were transplanted to CCl4-induced liver injured mice model, individually as well as together with melatonin. Two weeks after MSCs and MLT administration, all groups of mice were sacrificed for examination. Morphological and Histopathological results showed that combined therapy of MSCs+MLT showed substantial beneficial impact on CCl4-induced liver injured model, compared with MSCs and MLT individually. Biochemically, considerable reduction was observed in serum bilirubin and ALT levels of MLT+MSC treated mice, compared to other groups. PCR results shown down-regulation of Bax and up-regulation of Bcl-xl and Albumin, confirm a significant therapeutic effect of MSCs+MLT on CCI4-induced liver fibrosis. From the results, it is concluded that combined therapy of MSCs and MLT show strong therapeutic effect on CCL4-induced liver fibrosis, compared with MSCs and MLT individually.

Resumo A fibrose hepática é a fase inicial de qualquer doença hepática crônica, e em sua fase final desenvolve-se para cirrose. As doenças hepáticas crônicas são uma questão de saúde global crucial e a causa de aproximadamente 2 milhões de mortes por ano em todo o mundo. A cirrose, hoje em dia, é a 11ª causa mais comum de morte globalmente. O tratamento da célula-tronco mesenquimal (MSCs) é uma maneira eletiva de tratar a doença hepática aguda e crônica. O objetivo deste estudo é melhorar o potencial terapêutico dos MSCs combinados com a melatonina (MLT) para superar a fibrose hepática induzida por CCl4 e também investigar o impacto individual da melatonina e MSCs contra o comprometimento do fígado induzido por CCl4 no modelo animal. Os ratos BALB / C fêmeas foram usados como modelo de animal fibrótico de fígado induzido por CCl4. Cinco grupos de modelo animal foram feitos: Controle Negativo, Controle Positivo, CCl4 + MSCs Tratados Grupo, Grupo Tratado CCl4 + MLT e Grupo Tratado CCl4 + MSCs + MLT. MSCs cultivados da medula óssea dos ratos foram transplantados para o modelo de camundongos de fígado induzido por CCl4, individualmente, bem como em conjunto com a melatonina. Duas semanas após a administração MSCs e MLT, todos os grupos de camundongos foram sacrificados para o exame. Os resultados morfológicos e histopatológicos mostraram que a terapia combinada do MSCs + MLT mostrou impacto benéfico substancial no modelo ferido no fígado induzido pelo CCl4, em comparação com o MSCs e o MLT individualmente. A redução bioquimicamente considerável foi observada em bilirrubina sérica e níveis ALT de ratinhos tratados com MLT + MSCs, em comparação com outros grupos. Os resultados de PCR mostraram regulação negativa do BAX e regulação positiva do BCL-XL e da albumina, confirmando um efeito terapêutico significativo do MSCs + MLT na fibrose hepática induzida por CCl4. Dos resultados, conclui-se que a terapia combinada de MSCs e MLT mostram um forte efeito terapêutico na fibrose hepática induzida por CCl4, em comparação com MSCs e MLT individualmente.

Melatonin inhibits arrhythmias induced by increased late sodium currents in ventricular myocytes / 药学学报

Melatonin (Mel) has been shown to have cardioprotective effects, but its action on ion channels is unclear. In this experiment, we investigated the inhibitory effect of Mel on late sodium currents (INa.L) in mouse ventricular myocytes and the anti-arrhythmic effect at the organ level as well as its mechanism. The whole-cell patch clamp technique was applied to record the ionic currents and action potential (AP) in mouse ventricular myocytes while the electrocardiogram (ECG) and monophasic action potential (MAP) were recorded simultaneously in mouse hearts using a multichannel acquisition and analysis system. The results demonstrated that the half maximal inhibitory concentration (IC50) values of Mel on transient sodium current (INa.T) and specific INa.L opener 2 nmol·L-1 sea anemone toxins II (ATX II) increased INa.L were 686.615 and 7.37 μmol·L-1, respectively. Mel did not affect L-type calcium current (ICa.L), transient outward current (Ito), and AP. In addition, 16 μmol·L-1 Mel shortened ATX II-prolonged action potential duration (APD), suppressed ATX II-induced early afterdepolarizations (EADs), and significantly reduced the incidence of ventricular tachycardia (VT) and ventricular fibrillation (VF) in Langendorff-perfused mouse hearts. In conclusion, Mel exerted its antiarrhythmic effects principally by blocking INa.L, thus providing a significant theoretical basis for new clinical applications of Mel. Animal welfare and experimental process are in accordance with the regulations of the Experimental Animal Ethics Committee of Wuhan University of Science and Technology (2023130).

Effect of melatonin on otoprotection in rodents: a systematic review with meta-analysis

Abstract Objectives: To determinate the otoprotective efficacy of melatonin.in experimental models of rodents through a systematic review of the literature. Methods: Altogether, 154 articles were found in four databases. The PICOS strategy (Population, Intervention, Comparison, and Outcome) was used to define the eligibility criteria. Studies that met the inclusion criteria for the second step were included in a qualitative synthesis. Each study type was analyzed with the CAMARADES quality of assessment's checklist and the SYRCLE RoBS risk of bias. Results: Seven articles were selected, and four were included in the meta-analysis. It was possible to obtain seven outcomes according to the standard auditory frequencies presented among the studies, considering a minimum of three standard frequencies. The outcomes analyzed were for the frequencies of 1500, 2000, 3000, 4000, 5000, 6000, and 8000 Hz. Conclusion: Melatonin can provide protection against the ototoxic effects of cisplatin and aminoglycosides at 5000 Hz, 6000 Hz, and 8000 Hz, thereby minimizing the reduction in Otoacustic Emissions (OAE) amplitude. The same effect was not observed in the lower frequencies. Despite the limited number of studies that were evaluated, the results appeared consistent in higher frequencies. However, the methodology of the available studies did not meet the necessary methodological rigor that promotes the safe replicability of these studies.

Maternal obesity and its repercussions on melatonin and cortisol in breast milk and human colostrum

Introduction: scientific evidence has highlighted the role of chronobiological disruptions in promoting obesity through mechanisms involving important circadian rhythm hormones: melatonin and cortisol. These hormones are present in human colostrum and serve as crucial maternal and child protection mechanisms against obesity and childhood infections, owing to the intense interaction between mother and child during pregnancy and breastfeeding. Consequently, the melatonin and cortisol hormones present in human colostrum hold promise as potential candidates for yielding clinically applicable results and supporting future intervention strategies aimed at reducing obesity and neonatal infections. However, there is a scarcity of literature on this subject. Objective: the objective of this study is to to analyze the impact of maternal obesity on the levels and functions of melatonin and cortisol in colostrum and breast milk. Methods: a systematic review of the scientific literature was conducted following the recommendations outlined in the PRISMA protocol. Original articles published in English were searched in the PubMed, Medline, Lilacs, and Scopus databases. There were no restrictions on the publication year. Results: a total of 37 articles were identified from the searched databases. After removing duplicates and applying the inclusion and exclusion criteria, only five studies were relevant to the topic: two studies addressing melatonin and three studies analyzing cortisol. This review revealed that melatonin levels are elevated in the colostrum of obese women, and for this particular group, it has the potential to restore phagocyte activity and increase lymphocyte proliferation. Studies on cortisol have demonstrated that maternal obesity does not alter the levels of this hormone in breast milk. Conclusion: breastfeeding should be encouraged for all populations, and further original research should be conducted to elucidate the protective mechanisms of colostrum and breast milk.

Introdução: evidências científicas enfatizam que disrupções cronobiológicas podem promover a obesidade por mecanismos envolvendo ação de importantes hormônios marcadores do ritmo circadiano: a melatonina e cortisol. Estes hormônios estão presentes no colostro humano e representam importante mecanismo de proteção materno infantil frente à obesidade e infecções infantis, devido à intensa interação entre mãe e filho durante a gravidez e amamentação. Assim, os hormônios melatonina e cortisol presentes no colostro humano representam promissores candidatos para fornecer resultados com capacidade de aplicação clínica e de embasamento de futuras estratégias de intervenção com enfoque na redução da obesidade e de infecções neonatais. Entretanto, são escassos os estudos na literatura sobre o tema. Objetivo: analisar as repercussões da obesidade materna sobre os níveis e as ações da melatonina e do cortisol no colostro e leite materno. Método: foi realizada uma revisão sistematizada da literatura científica seguindo as recomendações do protocolo Prisma. Foram pesquisados artigos originais, publicados em inglês, nas bases de dados PubMed, Medline, Lilacs e Scopus. Não houve restrição quanto ao ano de publicação. Resultados: foram identificados 37 artigos nas bases de dados pesquisados, 15 artigos foram excluídos por estarem duplicados, após aplicação do critério de inclusão e exclusão apenas 5 estudos tiveram relação ao tema, sendo 2 estudos abordando sobre melatonina e 3 pesquisas que analisaram o cortisol. Esta revisão mostrou que a melatonina está elevada em colostro de obesas e para este grupo ela possui potencial de restaurar atividade de fagócitos e de elevar a proliferação de linfócitos. Os estudos sobre o cortisol ilustraram que os níveis deste hormônio no leite materno não foram alterados pela obesidade materna. Conclusão: o aleitamento materno deve ser encorajado para todos os públicos, assim como mais pesquisas originais devem ser desenvolvidas para descrever os mecanismos protetores do colostro e leite materno

Attenuation of hemodynamic responses to laryngoscopy and intubation by pre-operative oral melatonin

Background: Laryngoscopy and endotracheal intubation are usually associated with tachycardia and hypertension. Pre-administration of melatonin has anxiolytic and sedative property which can reduce the tachycardia and hypertension during the surgical procedures. Aims and Objectives: The present study aimed to evaluate the melatonin effect on hemodynamic changes during laryngoscopy and intubation. Materials and Methods: This prospective study was done in the department of anesthesia, Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bengaluru, Karnataka. Total 80 patients were included in the study based on the inclusion and exclusion criteria. Patients were divided into two groups. Group-A treated with placebo and Group-B treated with melatonin (6 mg) and demographic, clinical, and hemodynamic parameters were recorded. The data were analyzed with unpaired t-test with the use SPSS (20.0) version software. Results: Comparison of number and percentage of age, gender, and blood groups between the Group-I and Group-II not showed any significant difference. Group-I and Group-II mean age, height, and weight not showed any significant difference. Mean heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure were compared between the Group-I and Group-II at basal, during, after 1, 3, 5, and 10 min showed significant difference. Conclusion: Pre-administration melatonin showed significant reduction of hemodynamic changes compared to placebo group.

Immunohistochemical evidence of melatonin protection on lung tissue during chemotherapy / Evidencia inmunohistoquímica de la protección de la melatonina en el tejido pulmonar durante la quimioterapia

SUMMARY: The present study investigated the possible protective effects of melatonin on Bleomycin, Cisplatin and etoposide (BEP) chemotherapy regimens using immunohistochemistry. Forty male Wistar rats were divided into four groups of ten as; group 1 as untreated control; group 2 as BEP group which received the three cycles of 21 days' regimen each of 0.5¥ dose levels ofBEP (bleomycin 0.75 mg/kg, etoposide 7.5 mg/kg and cisplatin 1.5 mg/kg). Rats in the group 3 (MEL group) received 10 mg/kg/day melatonin once daily. Group 4 received the melatonin (30 min before the BEP injections) and BEP as in groups 2. Proliferating cell nuclear antigen (PCNA) staining was used to detect cell proliferation and caspase-3, caspase-9 and Caspase-8 were detected to investigate apoptosis. PCNA immunostaining in alveolar epithelium, alveolar macrophages and bronchus was weak to moderate in BEP group. However, diffuse and strong caspase immunoreactions for caspase-3, caspase 8- and caspase-9 were detected in the bronchioles epithelium, vascular endothelium, alveolar luminal macrophages in the BEP group. PCNA and caspase immunoreactivities in MEL and Mel + BEP groups were close to the control one. The surface are in the BEP group was significantly reduced as compared to the control one ((P0.05). It can be concluded that BEP regimen can affects negatively on lung tissue and melatonin inhibits lung tissue injuries during BEP chemotherapy.

El presente estudio investigó los posibles efectos protectores de la melatonina en los regímenes de quimioterapia con bleomicina, etopósido y cisplatino (BEP) mediante inmunohistoquímica. Cuarenta ratas Wistar macho se dividieron en cuatro grupos de diez: grupo 1, control sin tratar; grupo 2, quimioterapia con una dosis de 0,5x de BEP (0,75 mg/kg de bleomicina, 7,5 mg/ kg de etopósido y 1,5 mg/kg de cisplatino) con tres ciclos de 21 días cada uno. Las ratas del grupo 3 (grupo MEL) recibieron 10 mg/kg/día de melatonina una vez al día. El grupo 4 (Mel + BEP) recibió melatonina (30 minutos antes de las inyecciones de BEP) y BEP, como en los grupos 2. Se usó la tinción del antígeno nuclear de células en proliferación (PCNA) para detectar la proliferación celular y, caspasa- 3, caspasa-9 y caspasa-8 para investigar apoptosis. La inmunotinción de PCNA en el epitelio alveolar, los macrófagos alveolares y los bronquios varió de débil a moderada en el grupo BEP. Sin embargo, se detectaron inmunorreacciones difusas y fuertes para caspasa-3, caspasa 8- y caspasa-9 en el epitelio de los bronquiolos, endotelio vascular y macrófagos luminales alveolares. Las inmunorreactividades de PCNA y caspasa en los grupos MEL y Mel + BEP fueron similares a las del control. El área de superficie en el grupo BEP se redujo significativamente en comparación con el control (P0,05). Se puede concluir que la quimioterapia con BEP puede afectar negativamente al tejido pulmonar y la melatonina inhibe las lesiones durante la quimioterapia.

Time-dependent proregenerative effects of exogenous melatonin on the transected sciatic nerve / Efectos proregenerativos dependientes del tiempo de la melatonina exógena en el nervio ciático seccionado

SUMMARY: Microsurgical procedures are the treatment of choice of peripheral nerve injuries, but often fail to reach full functional recovery. Melatonin has neuroprotective actions and might be used as a possible proregenerative pharmacological support. Therefore, the aim of this study was to analyze the time-dependence of the neuroprotective effect of melatonin on the overall fascicular structures of both ends of the transected nerve. Sciatic nerve transection was performed in 34 adult male Wistar rats divided in four groups: two vehicle groups (N=7) treated intraperitoneally for 7 (V7) or 21 (V21) consecutive days with vehicle (5 % ethanol in Ringer solution) and two melatonin groups (N=10) administered intraperitoneally 30 mg/kg of melatonin for 7 (M7) or 21 (M21) consecutive days. At the end of the experiment, proximal stump neuroma and distal stump fibroma were excised and processed for qualitative and quantitative histological analysis. Intrafascicular neural structures were better preserved and the collagen deposition was reduced in the melatonin treated groups than in the vehicle groups. Myelin sheath regeneration observed through its thickness measurement was statistically significantly (p<0,05) more pronounced in the M21 (1,23±0,18 µm) vs. V21 group (0,98±0,13 µm). The mean volume density of the endoneurium was lower in both melatonin treated groups in comparison to the matching vehicle treated groups. Although not statistically different, the endoneural tube diameter was larger in both melatonin groups vs. vehicle groups, and the effect of melatonin was more pronounced after 21 days (24,97 % increase) vs. 7 days of melatonin treatment (18,8 % increase). Melatonin exerts a time-dependent proregenerative effect on nerve fibers in the proximal stump and an anti-scarring effect in both stumps.

Los procedimientos microquirúrgicos son el tratamiento de elección de las lesiones de los nervios periféricos, pero a menudo no logran una recuperación funcional completa. La melatonina tiene acciones neuroprotectoras y podría ser utilizada como un posible apoyo farmacológico proregenerativo. Por lo tanto, el objetivo de este estudio fue analizar la dependencia del tiempo del efecto neuroprotector de la melatonina sobre las estructuras fasciculares generales de ambos extremos del nervio seccionado. La sección del nervio ciático se realizó en 34 ratas Wistar macho adultas divididas en cuatro grupos: dos grupos de vehículo (N=7) tratados por vía intraperitoneal durante 7 (V7) o 21 (V21) días consecutivos con vehículo (5 % de etanol en solución Ringer) y dos grupos grupos de melatonina (N=10) a los que se les administró por vía intraperitoneal 30 mg/kg de melatonina durante 7 (M7) o 21 (M21) días consecutivos. Al final del experimento, se extirparon y procesaron el neuroma del muñón proximal y el fibroma del muñón distal del nervio para un análisis histológico cualitativo y cuantitativo. Las estructuras neurales intrafasciculares se conservaron mejor y el depósito de colágeno se redujo en los grupos tratados con melatonina respecto a los grupos con vehículo. La regeneración de la vaina de mielina observada a través de la medición de su espesor fue estadísticamente significativa (p<0,05) más pronunciada en el grupo M21 (1,23±0,18 µm) vs V21 (0,98±0,13 µm). La densidad de volumen media del endoneuro fue menor en ambos grupos tratados con melatonina en comparación con los grupos tratados con vehículo equivalente. Aunque no fue estadísticamente diferente, el diámetro del tubo endoneural fue mayor en ambos grupos de melatonina frente a los grupos de vehículo, y el efecto de la melatonina fue más pronunciado después de 21 días (aumento del 24,97 %) frente a los 7 días de tratamiento con melatonina (18,8 % de aumento). La melatonina ejerce un efecto proregenerativo dependiente del tiempo sobre las fibras nerviosas del muñón proximal y un efecto anticicatricial en ambos muñones.

Remote ischemic preconditioning-induced late cardioprotection: possible role of melatonin-mitoKATP-H2S signaling pathway

Purpose: Remote ischemic preconditioning (RIPC) confers cardioprotection against ischemia reperfusion (IR) injury. However, the precise mechanisms involved in RIPC-induced cardioprotection are not fully explored. The present study was aimed to identify the role of melatonin in RIPC-induced late cardioprotective effects in rats and to explore the role of H2 S, TNF-α and mitoKATP in melatoninmediated effects in RIPC. Methods: Wistar rats were subjected to RIPC in which hind limb was subjected to four alternate cycles of ischemia and reperfusion of 5 min duration by using a neonatal blood pressure cuff. After 24 h of RIPC or ramelteon-induced pharmacological preconditioning, hearts were isolated and subjected to IR injury on the Langendorff apparatus. Results: RIPC and ramelteon preconditioning protected the hearts from IR injury and it was assessed by a decrease in LDH-1, cTnT and increase in left ventricular developed pressure (LVDP). RIPC increased the melatonin levels (in plasma), H2 S (in heart) and decreased TNF-α levels. The effects of RIPC were abolished in the presence of melatonin receptor blocker (luzindole), ganglionic blocker (hexamethonium) and mitochondrial KATP blocker (5-hydroxydecanoic acid). Conclusion: RIPC produce delayed cardioprotection against IR injury through the activation of neuronal pathway, which may increase the plasma melatonin levels to activate the cardioprotective signaling pathway involving the opening of mitochondrial KATP channels, decrease in TNF-α production and increase in H2 S levels. Ramelteon-induced pharmacological preconditioning may also activate the cardioprotective signaling pathway involving the opening of mitochondrial KATP channels, decrease in TNF-α production and increase in H2 S levels.

The protective effects and mechanisms of melatonin on white matter damage in neonatal rats / 中国新生儿科杂志

Objective:To study the protective effects and mechanisms of melatonin (MTn) on lipopolysaccharide (LPS) and hypoxic-ischemic(HI) induced white matter damage (WMD) in neonatal rats.Methods:Seventy-two 3-day-old newborn Sprague-Dawley (SD) rats were randomly assigned into sham operation group (the sham group), model group (the HI group) and MTn intervention group (the HI+MTn group) ( n=24 for each group). For the sham group, only dissection of the right common carotid artery was performed without ligation. Animal models of WMD were established using LPS pretreatment and HI method in both the HI group and HI+MTn group. The HI+MTn group received MTn intraperitoneal injection (15 mg/kg, 1 h before LPS injection and then once daily). The HI group and the sham group received equal volume of normal saline containing 1% ethanol intraperitoneal injection. The rats were sacrificed on d7 of experiment and periventricular white matter (PVWM) was collected for hematoxylin-eosin (HE) and TUNEL staining to determine WMD and apoptosis. The distribution and morphology of microglial cells in the PVWM were studied using IBA1 immunofluorescence staining. Reactive oxygen species (ROS) kit was used to detect ROS. The expression of nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasomes, interleukin (IL)-1β, IL-18 and mitochondrial autophagy markers (pink1 and parkin) were determined using real-time quantitative PCR. Results:Compared with the sham group, the HI group showed WMD, cell degeneration and necrosis,increased cell apoptosis and increased expressions of NLRP3 inflammasomes and downstream inflammatory factors (IL-1β and IL-18) in PVWM. Compared with the HI group,the HI+MTn group showed reduced WMD, cell apoptosis, microglia infiltration and inflammatory factors expression. MTn increased pink1 and parkin expression and reduced ROS production in PVWM.Conclusions:MTn reduces ROS production by enhancing mitochondrial autophagy and inhibits NLRP3 inflammasomes hyperactivation to alleviate endotoxin- and HI-induced WMD in neonatal rats.

Breastfeeding and infant sleep:a review / 中国实用护理杂志

Sufficient and organized sleep is a key factor during the developmental process of infancy while disrupted sleep schedule and diseases might lead to sleeping disorders in infants. Breastfeeding is considered to be the most beneficial way to meet the nutritional needs of infants for optimal growth and development. The α-lactalbumin-tryptophan-melatonin axis, nucleotides, and other factors are breast milk components that may affect infant sleep. Meanwhile, diet, feeding schedule, tobacco smoking, alcohol intake, and caffeine consumption will affect the circadian rhythms which might lead to the fluctuations of sleep-influencing factors in breast milk. This study reviews literature of previous studies on this topic to summarize information that can be considered for both breastfeeding practice and future basic research on the establishment of organized sleep patterns in infants.

Pancreatic melatonin enhances anti-tumor immunity in pancreatic adenocarcinoma through regulating tumor-associated neutrophils infiltration and NETosis

Tumor microenvironment contributes to poor prognosis of pancreatic adenocarcinoma (PAAD) patients. Proper regulation could improve survival. Melatonin is an endogenous hormone that delivers multiple bioactivities. Here we showed that pancreatic melatonin level is associated with patients' survival. In PAAD mice models, melatonin supplementation suppressed tumor growth, while blockade of melatonin pathway exacerbated tumor progression. This anti-tumor effect was independent of cytotoxicity but associated with tumor-associated neutrophils (TANs), and TANs depletion reversed effects of melatonin. Melatonin induced TANs infiltration and activation, therefore induced cell apoptosis of PAAD cells. Cytokine arrays revealed that melatonin had minimal impact on neutrophils but induced secretion of Cxcl2 from tumor cells. Knockdown of Cxcl2 in tumor cells abolished neutrophil migration and activation. Melatonin-induced neutrophils presented an N1-like anti-tumor phenotype, with increased neutrophil extracellular traps (NETs) causing tumor cell apoptosis through cell-to-cell contact. Proteomics analysis revealed that this reactive oxygen species (ROS)-mediated inhibition was fueled by fatty acid oxidation (FAO) in neutrophils, while FAO inhibitor abolished the anti-tumor effect. Analysis of PAAD patient specimens revealed that CXCL2 expression was associated with neutrophil infiltration. CXCL2, or TANs, combined with NET marker, can better predict patients' prognosis. Collectively, we discovered an anti-tumor mechanism of melatonin through recruiting N1-neutrophils and beneficial NET formation.

Role of selenoprotein M knockdown in the melatonin antagonism of nickel-induced apoptosis and endoplasmic reticulum stress in mouse heart / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The aim of this study was to investigate the role of selenoprotein M (SelM) in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin. At 21 d after intraperitoneal injection of nickel chloride (NiCl2) and/or melatonin into male wild-type (WT) and SelM knockout (KO) C57BL/6J mice, NiCl2 was found to induce changes in the microstructure and ultrastructure of the hearts of both WT and SelM KO mice, which were caused by oxidative stress, endoplasmic reticulum stress, and apoptosis, as evidenced by decreases in malondialdehyde (MDA) content and total antioxidant capacity (T-AOC) activity. Changes in the messenger RNA (mRNA) and protein expression of genes related to endoplasmic reticulum stress (activating transcription factor 4 (ATF4), inositol-requiring protein 1 (IRE1), c-Jun N-terminal kinase (JNK), and C/EBP homologous protein (CHOP)) and apoptosis (B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), Caspase-3, Caspase-9, and Caspase-12) were also observed. Notably, the observed damage was worse in SelM KO mice. Furthermore, melatonin alleviated the heart injury caused by NiCl2 in WT mice but could not exert a good protective effect in the heart of SelM KO mice. Overall, the findings suggested that the antioxidant capacity of SelM, as well as its modulation of endoplasmic reticulum stress and apoptosis, plays important roles in nickel-induced heart injury.

Protective effect of melatonin against oxygen-induced retinopathy: a study based on the HMGB1/NF-κB/NLRP3 axis / 中国当代儿科杂志

OBJECTIVES@#To study the protective effect of melatonin (Mel) against oxygen-induced retinopathy (OIR) in neonatal mice and the role of the HMGB1/NF-κB/NLRP3 axis.@*METHODS@#Neonatal C57BL/6J mice, aged 7 days, were randomly divided into a control group, a model group (OIR group), and a Mel treatment group (OIR+Mel group), with 9 mice in each group. The hyperoxia induction method was used to establish a model of OIR. Hematoxylin and eosin staining and retinal flat-mount preparation were used to observe retinal structure and neovascularization. Immunofluorescent staining was used to measure the expression of proteins and inflammatory factors associated with the HMGB1/NF-κB/NLRP3 axis and lymphocyte antigen 6G. Colorimetry was used to measure the activity of myeloperoxidase.@*RESULTS@#The OIR group had destruction of retinal structure with a large perfusion-free area and neovascularization, while the OIR+Mel group had improvement in destruction of retinal structure with reductions in neovascularization and perfusion-free area. Compared with the control group, the OIR group had significant increases in the expression of proteins and inflammatory factors associated with the HMGB1/NF-κB/NLRP3 axis, the expression of lymphocyte antigen 6G, and the activity of myeloperoxidase (P<0.05). Compared with the OIR group, the OIR+Mel group had significant reductions in the above indices (P<0.05). Compared with the control group, the OIR group had significant reductions in the expression of melatonin receptors in the retina (P<0.05). Compared with the OIR group, the OIR+Mel group had significant increases in the expression of melatonin receptors (P<0.05).@*CONCLUSIONS@#Mel can alleviate OIR-induced retinal damage in neonatal mice by inhibiting the HMGB1/NF-κB/NLRP3 axis and may exert an effect through the melatonin receptor pathway.

Role of melatonin receptor 1B gene polymorphism and its effect on the regulation of glucose transport in gestational diabetes mellitus / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Melatonin receptor 1B (MT2, encoded by the MTNR1B gene), a high-affinity receptor for melatonin, is associated with glucose homeostasis including glucose uptake and transport. The rs10830963 variant in the MTNR1B gene is linked to glucose metabolism disorders including gestational diabetes mellitus (GDM); however, the relationship between MT2-mediated melatonin signaling and a high birth weight of GDM infants from maternal glucose abnormality remains poorly understood. This article aims to investigate the relationship between rs10830963 variants and GDM development, as well as the effects of MT2 receptor on glucose uptake and transport in trophoblasts. TaqMan-MGB (minor groove binder) probe quantitative real-time polymerase chain reaction (qPCR) assays were used for rs10930963 genotyping. MT2 expression in the placenta of GDM and normal pregnant women was detected by immunofluorescence, western blot, and qPCR. The relationship between MT2 and glucose transporters (GLUTs) or peroxisome proliferator-activated receptor γ (PPARγ) was established by western blot, and glucose consumption of trophoblasts was measured by a glucose assay kit. The results showed that the genotype and allele frequencies of rs10830963 were significantly different between GDM and normal pregnant women (P<0.05). The fasting, 1-h and 2-h plasma glucose levels of G-allele carriers were significantly higher than those of C-allele carriers (P<0.05). Besides, the protein and messenger RNA (mRNA) expression of MT2 in the placenta of GDM was significantly higher than that of normal pregnant women (P<0.05). Melatonin could stimulate glucose uptake and GLUT4 and PPARγ protein expression in trophoblasts, which could be attenuated by MT2 receptor knockdown. In conclusion, the rs10830963 variant was associated with an increased risk of GDM. The MT2 receptor is essential for melatonin to raise glucose uptake and transport, which may be mediated by PPARγ.

Role of lysosomal damage in senescence of SH-SY5Y cells induced by methylmercury and intervention of melatonin / 环境与职业医学

Background Methylmercury (MeHg) is a neurotoxin, and melatonin (MT) has a protective effect on the nervous system, but whether it can antagonize MeHg-induced nerve cell damage and the associated mechanism remain unknown. Objective Human neuroblastoma cells (SH-SY5Y cells) were used as research objects. A MeHg-induced SH-SY5Y cell senescence model was established to observe autophagy related protein, lysosomal number, and function changes, as well as potential intervention role and associated mechanism of MT. Methods (1) After SH-SY5Y cells were treated with different doses of MeHg (0, 0.125, 0.25, 0.5, 1, 2, and 4 μmol·L−1) for 48 h, the cell viability was detected using a cell viability detection kit (CCK-8 method) and the viability rate was calculated. Senescent cells were detected by an acidic senescence-associated-β-galactosidase (SA-β-gal) staining. (2) A MeHg dose of 0.5 μmol·L−1 that significantly induced senescence of SH-SY5Y cells was screened, and a half and a quarter of the dose (0.25 and 0.125 μmol·L−1) were used for the middle and low dose groups, respectively. (3) In the MT intervention experiments, SH-SY5Y cells were divided into four groups, including control group (0.1% DMSO), MeHg group (0.5 μmol·L−1 MeHg), MT group (1 mmol·L−1 MT), and MT intervention group (1 mmol·L−1 MT+0.5 μmol·L−1 MeHg). In the MT intervention group, cells were exposed to 0.5 μmol·L−1 MeHg for 48 h after 24 h of 1 mmol·L−1 MT pretreatment. (4) SA-β-gal staining was conducted to observe cell senescence; Western blotting for the expression levels of senescence-associated protein p16, autophagy-associated protein p62, LC3Ⅱ, and lysosomal-associated proteins LAMP1, LAMP2, and TFEB; Lyso-Tracker Red for the quantity of lysosomes; LysoSensor Green DND-189 for lysosomal pH changes; electron microscope for the morphological changes of lysosomes. Results The results of CCK-8 indicated that the viability rate of cells decreased with the increase of MeHg exposure concentration. Compared with the control group, the SA-β-gal positive cell ratio in the 0.5 μmol·L−1 MeHg group increased by 48% (P<0.01), p16, p62, as well as LC3Ⅱ protein expressions were significantly increased (P<0.05), LAMP1 and LAMP2 protein levels, as well as the fluorescence intensities of lysosomal red and green fluorescent probes decreased with the increase of MeHg concentration (P<0.05), and the volume of lysosomes increased under the electron microscope. Compared with the MeHg group, the expression of p16 protein was decreased in the 1 mmol·L−1 MT + 0.5 μmol·L−1 MeHg group and the SA-β-gal positive cell ratio was significantly decreased by 19% (P<0.05), the protein levels of p62 and LC3Ⅱ were significantly decreased, the LAMP1 and LAMP2 protein levels and the fluorescence intensities of lysosomal red and green fluorescent probes were increased respectively, the nuclear entry of TFEB was significantly increased, and the differences were statistically significant (P<0.05). Conclusion MeHg may cause cellular senescence by reducing the number of lysosomes and impairing lysosomal activity in SH-SY5Y cells, and MT may ameliorate MeHg-induced lysosomal abnormalities in SH-SY5Y cells, thereby intervening cell senescence.

Fisiopatología de la programación fetal y su repercusión en la salud futura / Pathophysiology of fetal programming and its impact on the future health

Resumen ANTECEDENTES: Durante la vida intrauterina, las alteraciones en el microambiente fetal causadas por desequilibrios nutricionales y metabólicos de la madre pueden dejar huellas epigenéticas y efectos persistentes en la vida adulta de su hijo que habrán de predisponerlo a enfermedades crónicas futuras. OBJETIVO: Llevar a cabo una revisión sistemática de la fisiopatología de la programación fetal y su repercusión en la salud futura del feto. METODOLOGÍA: Búsqueda en la base de datos de PubMed de artículos publicados, en los últimos 10 años, en inglés o español, con los MeSH "fetal programming"; "pathophysiology", con su correspondiente traducción. Se incluyeron artículos originales y de revisión con criterios PRISMA para revisiones sistemáticas. RESULTADOS: Se encontraron 38 artículos, y se agregaron 7 de información complementaria y sustento para la discusión. En su análisis queda clara la relación entre las condiciones fisiopatológicas reportadas de desnutrición, sub y sobrealimentación, diabetes mellitus gestacional, obesidad, resistencia a la insulina, glucocorticoides y preeclampsia con enfermedades de la infancia, adolescencia y adultez. Se encontró evidencia de disruptores endocrinos, melatonina y disbiosis con enfermedades de la infancia y vida adulta. Así mismo, la interrupción de la angiogénesis durante el desarrollo pulmonar que conduce a hipertensión arterial pulmonar y enfisema, todo ello originado por la programación fetal epigenética. Se encontraron diferencias en el patrón de metilación de placentas prematuras en comparación con las de término. CONCLUSIONES: Las anormalidades que sobrevienen durante el embarazo modifican la programación fetal y dan pie a las enfermedades que aparecerán durante la infancia, adolescencia y adultez, como consecuencia de los cambios en el patrón de metilación de los genes.

Abstract BACKGROUND: During intrauterine life, alterations in the fetal microenvironment caused by maternal nutritional and metabolic imbalances may leave epigenetic imprints and persistent effects on fetal adult life that will predispose the fetus to future chronic diseases. OBJECTIVE: To carry out a systematic review of the pathophysiology of fetal programming and its impact on the future health of the fetus. METHODOLOGY: Search in the PubMed database of articles published in the last 10 years, in English or Spanish, with the MeSH "fetal programming"; "pathophysiology", with their corresponding translation. Original and review articles with PRISMA criteria for systematic reviews were included. RESULTS: Thirty-eight articles were found, and seven were added for complementary information and support for discussion. In their analysis the relationship between the reported pathophysiological conditions of under-, under- and over-nutrition, gestational diabetes mellitus, obesity, insulin resistance, glucocorticoids and pre-eclampsia with diseases of childhood, adolescence and adulthood is clear. Evidence of endocrine disruptors, melatonin and dysbiosis was found with diseases of childhood and adulthood. Also, disruption of angiogenesis during lung development leads to pulmonary arterial hypertension and emphysema, all caused by epigenetic fetal programming. Differences were found in the methylation pattern of preterm placentas compared to term placentas. CONCLUSIONS: Abnormalities that occur during pregnancy modify fetal programming and give rise to the diseases that will appear during childhood, adolescence, and adulthood, because of changes in the methylation pattern of genes.

Role of melatonin in attenuation of hemodynamic response to intubation and anesthetic requirements: a randomized, controlled, double-blind study

Abstract Background Melatonin has been studied to have anxiolytic, sedative, and analgesic effects. However, there is limited data on the effect of melatonin in the attenuation of hemodynamic response to intubation. We aimed to study whether preanesthetic oral melatonin attenuates hemodynamic responses to intubation and anesthetic requirements. Methods Sixty-four patients scheduled for laparoscopic cholecystectomy were randomized into melatonin or placebo group (n = 32 each). Melatonin group received two tablets (3 mg each) of melatonin, and the placebo group received two tablets of vitamin D3 120 min before induction. Hemodynamic parameters were recorded during induction and postintubation for 15 minutes. Total induction dose of propofol, total intraoperative fentanyl consumption, and adverse effects of melatonin were also noted. Results Postintubation rise in heart rate (HR) was less in the melatonin group compared to the placebo group (10.59% vs. 37.08% at 1 min, respectively) (p< 0.0001). Maximum percentage increase in systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean blood pressure (MBP) was lesser in melatonin group than placebo group (SBP 9.25% vs. 37.73%, DBP 10.58% vs. 35.51%, MBP 9.99% vs. 36.45% at 1 min postintubation. respectively) (p< 0.0001). Induction dose of propofol (1.42 mg.kg-1 vs. 2.01 mg.kg-1) and the number of patients requiring additional fentanyl intraoperatively (3 vs. 11) were also significantly reduced in the melatonin group. Conclusion Premedication with 6 mg of oral melatonin resulted in significant attenuation of postintubation rise in HR, SBP, DBP, and MBP. It also reduced the induction dose of propofol, total intraoperative fentanyl consumption without any adverse effects.

Evaluation of the effect of melatonin in patients with Burning mouth syndrome: a double-blind, placebo-controlled randomized clinical trial

Abstract The present study was carried out to evaluate the effect of Melatonin and Placebo in the patient with the Burning mouth (BMs). This double-blind, placebo-controlled randomized clinical trial study was carried out on 30 patients who were suffering from BMS. During this period patients were divided into 2 study and control groups. The study group used four 3 mg Melatonin daily and the control group received a placebo. Then the severity of the burning sensation was measured by the physician Sleep quality was measured using the VAS scale using the Petersburg questionnaire. Data in the application Enter SPSS 20 and then using T test or equivalent Nonparametric was analyzed, mean sleep score and mean severity of oral irritation before and after treatment in two the group was evaluated using T-test Independent. Level significance was considered 0.05. The results of the present study show that the use of melatonin and a placebo in patients with BMS reduces sensation and improves their sleep quality, although it may not reduce it completely. In this study severity of burning was 4.93±2.56 after treatment in the study group and 6.93±2.12 in the control group, which was statistically significant (P =0.036). No significant difference was observed between the two groups in the sleep quality score (P-value = 0.43). Using Melatonin can be a reliable way to treat pain for which there is no standard treatment to date. Although evidence suggests an association between sleep disorders and BMS, melatonin was not superior to a placebo in reducing BMS-induced burning in the present study. Identification of stressors and the ways to struggle with them, further studies with larger samples and higher oral doses, extended follow-up periods and control of psychological factors, and measurement of body mass index that may affect pharmacokinetics are recommended.