Serum Melatonin Research Articles

Effects of magnesium and potassium supplementation on insomnia and sleep hormones in patients with diabetes mellitus.

Diabetes mellitus is a metabolic condition with hyperglycemia. Literature has shown a correlation between poor sleep quality and duration with an increased incidence of insomnia in diabetic individuals. The goal of this study was to determine the magnesium and potassium supplementation effect among diabetic individuals with insomnia. A randomized controlled trial (single blind) was conducted on 320 patients with diabetes; after 2 months of follow-up, 290 patients completed the trial. The Insomnia Severity Index (ISI) was used to assess the severity and duration of insomnia, before and after the trial. Tablets containing supplements were prepared: placebo (T1), magnesium (Mg, T2), potassium (K, T3), and a combination of Mg and K (T4). Melatonin and cortisol (sleep hormones) were measured from blood (serum) using an enzyme-linked immunosorbent assay (ELISA), before and after the trial. The study included 93 (32.1%) male and 197 (67.9%) female participants. According to the analysis, there was a significant association between the treatment groups and ISI after the trial (post-trial), p = 0.0001. Analysis showed that there was significant association between pre- and post-serum cortisol levels in treatment groups 2, 3, and 4 (T2, T3, and T4) as p-values are 0.001, 0.001, and 0.001 respectively. Similar findings were observed for serum melatonin. The study revealed that magnesium, potassium, and magnesium and potassium combined had a significant effect on serum cortisol and melatonin levels (sleep hormones). In addition, supplementation significantly decreased the severity of insomnia among patients with diabetes by improving sleep duration.

Serum melatonin levels and in a sample of Iranian patients with migraine

Migraine, a complex disorder, is characterized by recurrent headache episodes. The production of melatonin in the pineal gland, which is crucial for controlling circadian rhythms and sleep–wake cycles, is altered in various conditions, including neurological disorders such as migraine. Recent studies underscore the significance of serum melatonin levels in patients with chronic and episodic migraine, the focus of this study. This case‒control study, conducted from September 2017 to June 2020 in Tehran, Iran, selected potential participants aged 18–65 years from a headache clinic at Sina Hospital (affiliated with Tehran University of Medical Sciences). Both episodic migraine and chronic migraine were diagnosed following the diagnostic criteria in the International Classification of Headache Disorders’ third edition. Melatonin levels were measured according to the instructions of the ELISA kits. There were significant differences in the frequency of headache days and the duration of abortive medication usage between the two groups (P value < 0.001). Besides, analysis revealed significantly lower serum melatonin levels in patients with episodic ((80.45–45.06) 72.83) and chronic migraine ((154.34–63.34) 70.38, P value < 0.001) than in healthy controls (281.25–160.86) 280). Although no considerable differences were found between episodic and chronic migraine patients, the current study demonstrated that serum melatonin levels were substantially greater in healthy controls than in patients with migraine.

Nanostructured electrochemical platform for sensitive detection of melatonin in human serum and tablets

Melatonin (MT) is a crucial hormone for biological rhythms that influences sleep-wake cycles. The therapeutic value of MT in neurological disorders highlights the need for precise detection. However, challenges like low concentrations in biological samples and complex matrix interferences persist, necessitating rapid and precise analytical techniques. This study presents the novelty of designing a novel sensor that combines a molecularly imprinted polymer with polytoluidine blue O (PTBO) and multi-walled carbon nanotubes on a glassy carbon electrode for MT detection and the study of the interaction between MT and the proposed sensor using density functional theory (DFT). DFT showed that MT has a high nucleophilic character and low electrophilicity compared to TBO, which is a strong electrophile. This supports electron transfer from MT to TBO/PTBO, as indicated by the electronic chemical potentials and molecular electrostatic potentials. Scanning electron microscopy was used to see the morphology. Electrochemical measurements using differential pulse voltammetry demonstrated enhanced sensitivity and selectivity. Under optimized conditions, the sensor exhibited a linear response ranging from 1 to 1000 µM with a limit of detection and limit of quantification of 0.027 µM and 0.092 µM respectively. The performance of the sensor was evaluated in pharmaceutical tablets and human serum. Validation experiments confirmed the reliability of the sensor, with recovery rates of 97.5 % for serum and 98.0 % for pharmaceutical tablets, alongside low relative standard deviations indicating good precision. Interference studies showed minimal effects from coexisting substances, highlighting the selectivity of the proposed sensor. Comparative analysis with existing sensors showed superior performance.

Effects of integrative therapy with Du Meridian moxibustion, ear acupuncture, and alprazolam on cardiac function and neurotransmitter levels in patients with coronary heart disease and insomnia: An observational study.

To explore the effects of Du Meridian moxibustion combined with ear acupuncture on clinical symptoms and serum neurotransmitters in patients with coronary heart disease and insomnia. This study is a retrospective study. From June 2021 to May 2023, 116 patients with coronary heart disease and insomnia treated at our hospital were selected as subjects. They were divided into 2 groups according to the treatment. The control group received treatment with alprazolam, while the experimental group received Du Meridian moxibustion combined with ear acupuncture in addition to alprazolam treatment. The efficacy of the 2 groups was compared, and the levels of cardiac function indicators, serum melatonin, leptin, and neurotransmitters were measured. The total effectiveness rate in the experimental group was 93.10% (with a cure rate of 36.21%, a significant improvement rate of 41.38%, and an effective rate of 15.52%), which was significantly higher than the 79.31% in the control group (with a cure rate of 24.14%, a significant improvement rate of 32.76%, and an effective rate of 22.41%) (P < .05). Both groups exhibited an increase in left ventricular ejection fraction, stroke volume, and cardiac output after treatment compared to before treatment. Additionally, left ventricular end-systolic diameter decreased after treatment compared to before treatment, but the cardiac function was compared between the 2 groups after treatment (P > .05). In both groups, serum melatonin and serotonin (5-HT) levels increased after treatment compared to before treatment, while serum leptin, dopamine, and glutamate levels decreased after treatment compared to before treatment. Furthermore, the experimental group had higher serum melatonin, 5-HT, and gamma-aminobutyric acid levels compared to the control group, and lower serum leptin, dopamine, and glutamate levels compared to the control group (P < .05). The serum traditional Chinese medicine syndrome score and Pittsburgh sleep quality index score of the 2 groups decreased after treatment, and the experimental group was lower than the conventional group (P < .05). The combination of Du Meridian acupuncture with ear acupuncture in the treatment of insomnia in coronary heart disease can regulate the expression of serum melatonin, leptin, and neurotransmitters, alleviate symptoms, and improve therapeutic efficacy.

Impact of oral melatonin supplementation on urine and serum melatonin concentrations and quality-of-life measures in persons with relapsing multiple sclerosis

IntroductionMelatonin is an antioxidant and anti-inflammatory agent that modulates the immune system by scavenging free radicals, reducing the upregulation of pro-inflammatory cytokines, and reducing transendothelial cell migration. Therefore, melatonin may play a role in regulating multiple sclerosis (MS) disease activity. However, little is known about how melatonin supplementation effects individuals with MS. ObjectiveDetermine if there was a dose-dependent elevation in urine and serum melatonin concentrations. Determine if melatonin supplementation had an impact on patient reported outcomes. MethodsThis was a randomized, dose-blinded exploratory study. Adults (age 18–65) with relapsing forms of multiple sclerosis (RMS) treated with a stable dose of oral disease modifying therapy for at least 6 months were randomized into melatonin 3 mg or 5 mg daily. Urinary and serum melatonin levels and modified fatigue impact scale (MFIS), multiple sclerosis impact scale (MSIS-29), and Pittsburgh sleep quality index (PSQI), patient determined disease steps (PDDS) and performance scales (PS) were measured at baseline, 3, 6, and 12 months. Urinary and serum melatonin analyses was performed to estimate mean concentrations and their differences between treatment arms over time by a repeated measures linear mixed model. The model included treatment, assessment time, and treatment × time interaction. ResultsThirty patients, randomized 1:1, were analyzed in an intent to treat population. Twenty-three completed the study. The repeated measures linear mixed model analysis of all timepoints revealed higher melatonin concentrations in patients on 5 mg compared to 3 mg melatonin for both urinary 6-SMT (p = 0.03) and serum melatonin (p = 0.04). MFIS, MSIS-29, PSQI, and PDSS-PS scores did not significantly change from baseline to month 12. No significant differences in these measures were seen between the two doses. Five patients stopped melatonin (three on 5 mg and two on 3 mg) due to adverse events, including one patient who developed focal spongiotic dermatitis. One patient experienced three consecutive serious adverse events that were unrelated to melatonin supplementation. ConclusionsThe 5 mg melatonin supplementation group had higher concentrations of urinary 6-SMT and serum melatonin compared to the 3 mg group over 12 months of treatment. There was a correlation between 6-SMT and serum melatonin concentrations. This suggests that measuring serum melatonin is a reliable alternative to measuring urinary 6-SMT. However, no differences in clinical benefit between the two dosage groups were demonstrated in the patient reported outcomes. Trial Registration NumberNCT03498131

Gut microbiota-melatonin signaling axis in acute pancreatitis: Revealing the impact of gut health on pancreatic inflammation and disease severity in a case-control study.

Acute pancreatitis (AP), a severe inflammatory condition affecting the pancreas requires investigation into its predictors. Melatonin, a compound with anti-inflammatory and antioxidant properties, has shown promise in managing AP. Additionally, the gut microbiota, a community of microorganisms residing in the intestines has been linked to AP development. This study aims to explore the correlation between melatonin and gut microbiota in predicting AP severity. This study involved 199 participants, with 99 diagnosed with AP and 100 serving as healthy controls. The AP patients were categorized into 2 groups based on the severity of their condition: mild AP (MAP) and severe AP (SAP). Serum melatonin levels were measured on Days 1, 3, and 5 of hospitalization, and gut microbiota composition was examined via 16S rRNA gene sequencing. Other parameters were evaluated, such as the Acute Physiology and Chronic Health Evaluation (APACHE) score, Ranson, and Acute Gastrointestinal Injury (AGI) scores. Melatonin levels were significantly lower in subjects with severe AP compared those with mild AP (18.2 ng/mL vs 32.2 ng/mL, P = .001), and melatonin levels decreased significantly in patients with AP on Days 3 and 5. The study also revealed that individuals with AP exhibited a significantly altered gut microbiota composition compared to control individuals, with a lower Shannon index and higher Simpson index. The AUCs for Simpson index and F/B ratio were significantly higher than those for other biomarkers, indicating that these gut microbiota markers may also be useful for AP prediction. The study proposes that there is a relationship between melatonin levels and the dynamics of gut microbiota profiles in relation to the severity of AP. As a result, the severity of the disease can be assessed by assessing the levels of serum melatonin and gut microbiota profiles.

Melatonin mediates intestinal barrier dysfunction and systemic inflammation in moderate-severe OSA patients

Background Intestinal barrier dysfunction and systemic inflammation are common in obstructive sleep apnoea (OSA). We aimed to investigate the role of melatonin, an anti-inflammatory mediator, in mediating the relationships between OSA, intestinal barrier dysfunction and systemic inflammation. Methods Two hundred and thirty-five male participants who complained with sleep problems and underwent whole night polysomnography at our sleep centre between 2017 and 2018 were enrolled. Polysomnographic data, anthropometric measurements and biochemical indicators were collected. Serum melatonin, intestinal barrier function biomarker zonula occludens-1 (ZO-1) and inflammatory biomarkers C-reactive protein (CRP) with lipopolysaccharide (LPS) were detected. Spearman’s correlation analysis assessed the correlations between sleep parameters, melatonin and biomarkers (ZO-1, LPS and CRP). Mediation analysis explored the effect of OSA on intestinal barrier dysfunction and systemic inflammation in moderate-severe OSA patients. Results As OSA severity increased, serum melatonin decreased, whereas ZO-1, LPS and CRP increased. Spearman’s correlation analysis showed that serum melatonin was significantly negatively correlated with ZO-1 (r = −0.19, p < .05) and LPS (r = −0.20, p < .05) in the moderate-OSA group; serum melatonin was significantly negatively correlated with ZO-1 (r = −0.46, p < .01), LPS (r = −0.35, p < .01) and CPR (r = −0.30, p < .05) in the severe-OSA group. Mediation analyses showed melatonin explain 36.12% and 35.38% of the effect of apnoea–hypopnea index (AHI) on ZO-1 and LPS in moderate to severe OSA patients. Conclusions Our study revealed that melatonin may be involved in mediating intestinal barrier dysfunction and systemic inflammation in moderate-to-severe OSA patients.

The effect of phototherapy treatment on serum melatonin levels in term newborns.

The aim of this study was to investigate the effect of phototherapy treatment on serum melatonin levels in term newborn infants. This study was planned as a single-center, prospective, observational, case-control study. Term infants (gestation week ≥37 weeks) who received at least 6 h of phototherapy due to jaundice constitute the phototherapy group, while the term infants without jaundice and who were exclusively breastfed constitute the control group. Melatonin levels were examined by taking blood samples from babies in both groups at 02:00 at night. Melatonin values were compared between groups. The effect of phototherapy on serum melatonin levels was investigated. The relationship between the duration of phototherapy and maximum serum bilirubin values on melatonin values was investigated. Seventy term infants (64.3% girls) were included in the study. Mean gestational week was 38.3 ± 1.1 weeks, mean birth weight was 3295 ± 434 g. There was no statistically significant difference between the phototherapy group and the control group in terms of sex, type of delivery, gestational week, birth weight, height, and head circumference (all p > 0.05). Serum melatonin level was 20.3 ± 5.9 pg/mL (range: 8.7-36.6 pg/mL) in the phototherapy group and 19.9 ± 4.38 pg/mL (range: 9.9-26.3 pg/mL) in the control group. There was no significant difference between the two groups in terms of serum melatonin levels (p = 0.155). The mean total bilirubin value was 17.65 ± 1.48 mg/dL, and the average duration of phototherapy application was 13.94 ± 7.64 h in the babies in the phototherapy group. No correlation was found between the duration of phototherapy application and serum melatonin levels (p = 0.791). It was determined that there was no significant difference in serum melatonin levels in term newborn babies who received phototherapy for at least 6 h due to jaundice. No correlation was found between the duration of phototherapy application and the serum melatonin level of the maximum bilirubin values.

Validation of a simple bioanalytical method for the determination of melatonin concentration in human serum using high-performance liquid chromatography with a fluorescent detector

Analysis of melatonin in biological samples is a challenge for the analyst both because of its low concentration and because of the numerous interfering substances. Therefore, chromatography, as a powerful analytical technique used for the separation, detection, and quantification of analytes, can be the method of choice for determining melatonin in biological samples for clinical use and pharmacokinetic research. The method was developed and validated according to the internal documents in accordance with Good Laboratory Practice. The concentrations of melatonin in human serum were determined using a high-performance liquid chromatography method with a fluorescence detector and mirtazapine as an internal standard. Preparation of serum samples was performed by liquid–liquid extraction with ethyl acetate: n-hexane (1:1 v/v). High linearity was exhibited over a concentration range of 25–10,000 pg/mL of melatonin, with a correlation coefficient higher than 0.999 during the course of method validation. Repeatability and intermediate precision show a relative standard deviation lower than 6.6 %, and accuracies were from 90.7 % to 110.3 %. The lower limit of quantitation was 30 pg/mL, and the limit of detection was 7.92 pg/mL. The in-house method is simple, fast, reproducible, and applicable for the determination of melatonin in human serum.

Correlation between serum melatonin and cortisol levels in clinically healthy subjects

Correlation between serum melatonin and cortisol levels in clinically healthy subjects

Enhancing Sleep Quantity and Quality with a Novel GABAergic Dietary Supplement

Purpose: The primary objective of this investigation was to evaluate the effects of BH_SLP_01 (Bonafide Health Sleep Product) on sleep quality and brain wave patterns using a caffeine-induced insomnia model, and on sleep duration and latency using a pentobarbital-induced sleep model. Methods: Five male BALB/c mice were allocated per treatment arm (age: 8 weeks, body mass: 180 ± 20 g). Treatment arms included control, caffeine or phenobarbital (active) control, and BH_SLP_01. Caffeine treatment model. To induce sleep disturbance, 7.5 mg/kg caffeine was injected intraperitoneally at the 15th minute (min) of recordings, and second injections (saline or combinations) were performed at the 30th minute. Brain electrical activity was monitored and recorded for a total of two hours using electrocorticography (ECoG) recording. Serum melatonin, serotonin, and dopamine were measured by ELISA. Brain levels of MDA were measured by HPLC, and protein concentrations were determined using Western Blot analysis. Phenobarbital treatment model Groups were administered saline or BH_SLP_01, and then, 45 min later, pentobarbital (42 mg/kg) was injected. After injection, sleep latency and duration were measured. Study treatments were compared using an ANOVA and Student's unpaired t-test. Significance levels were set at p&lt;0.05. Results: Analysis of ECoG recording data revealed notable findings. In the caffeine-pretreated group, a significant increase in amplitude was observed during the 30-45 min interval, compared to control. Caffeine administration also significantly increased frequency at 75-90 and 90-105 min compared to control (p&lt;0.05). Conversely, the group treated with BH_SLP_01 displayed no significant changes in amplitude and frequency, except for a significant change in frequency at 90-105 min compared to control (p&lt;0.05). Both sleep duration and sleep latency were significantly improved for BH_SLP_01 compared to control and phenobarbital control (p&lt;0.05). In addition, serotonin, dopamine, melatonin, GABAA R2, GABAB R1, GABAB R2, 5-HT1A, GluA1, GluN1, GluN2A, Bax, Bcl-2, and Caspase-3 levels were significantly improved by BH_SLP_01 compared to control and caffeine control (p&lt;0.05). Conclusion: The results of these studies provide evidence for the effcacy of BH_SLP_01 to improve impaired sleep, leading to notable enhancements in markers of deep sleep. This conclusion is supported by the significant upregulation of GABA, glutamine receptors, and endogenous melatonin, all of which collectively contribute to the augmentation of both sleep quantity and quality. These findings underscore the potential of BH_SLP_01 as a promising therapeutic intervention for optimizing sleep parameters and promoting overall sleep wellness. This research was supported by Bonafide Health, LLC. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Assessment of the dalargin effect on the level of vitamin D and melatonin in blood serum in patients with malignant bone tumors and polymorbidity

Background. Involved in many cascades of biological regulatory reactions, calcium, vitamin D and melatonin create a single metabolic pattern, maintaining the dynamic balance of bone tissue homeostasis. Nevertheless, these regulatory molecules, as structural and functional elements of bone tissue, play a crucial role in various cellular processes associated with oncogenesis and tumor progression. Synthetic peptide dalargin has wound healing, reparative, anti-inflammatory, antioxidant, immunomodulatory, anticarcinogenic, antitumor, and antimetastatic effects. The purpose of the study was to investigate the synthetic neuropeptide dalargin influence on the dynamics of vitamin D and melatonin blood serum le­vels as part of the treatment algorithm of patients with bone malignant tumors of the lower extremities and pelvis with polymorbidity and endoprosthetics. Materials and methods. The study inclu­ded a control (first) group and a main (second) group of clinical observation of patients with malignant bone lesions. The serum melatonin content was measured by enzyme immunoassay using reagent kits (No. RE54021) from IBL-Hamburg GmbH (Germany). Serum levels of 25-hydroxycalciferol (25(OH)D) were determined by the immunochemiluminescent method on an ARCHITECT 25-OH Vitamin D Controls automatic analyzer. Results. In patients who received dalargin, more pronounced positive dynamics were established in the normalization of 25(ОН)D and melatonin levels, and there was no exacerbation of concomitant diseases. In contrast to the data of patients who did not receive dalargin, in the group where it was used, there were no relapses or metastases of the tumor du­ring 14 months. A comparison of the 25(ОН)D and melatonin le­vels in patients 6–7 months and 12–14 months after treatment shows a tendency to recovery of indicators only in patients who were additionally treated with dalargin (p &lt; 0.01). Conclusions. The study showed the possibility of using the neuropeptide dalargin to increase the effectiveness of the treatment of patients with primary malignant tumors with the burden of polymorbidity by influencing the levels of vitamin D and melatonin in the blood serum.

The effects of endogenous melatonin on brain tissue oxidative stress induced by photoperiodic alterations and iron overloading in rats

Melatonin is a potent endogenously occurring antioxidant with the pleiotropic activities to neurodegenerative diseases associated with brain oxidative damage. In this study, we examined the prolonged photoperiodic alterations and iron (Fe) overload on melatonin production and brain oxidative stress in rats. The result showed that the 15 days of constant light (CL) exposure did not low the melatonin production but the 15 days of constant darkness (CD) significantly increased serum melatonin level in rats. The Fe treatment in both CL and CD conditions significantly reduced endogenous melatonin levels and increased brain tissue lipid peroxidation. Fe as a toxic transition metal can induce Fenton reaction to generated hydroxyl radical which can damage the neuronal cell membrane and impair the brain antioxidant system. In the current study, we observed the imbalanced antioxidant defense alterations upon Fe treatment in rat brain including the increased levels of alpha-tocopherol (α-T) and total thiols and the reduced melatonin level and catalase (CAT) activity. We speculated that the reduced melatonin level caused by Fe was due to its consumption since melatonin served as a metal chelator and antioxidant. Understanding these aspects enhances knowledge of brain Fe metabolism and its role in neurodegenerative disorders as well as the potential protective effects of melatonin on this metal.

Melatonin Against Aging: Could We Stimulate Melatonin Secretion Through Tahajjud?

Background: Islamic instructions suggest waking up near dawn and praying to Allah. This is the time of maximum melatonin secretion, a hormone whose main function is regulating the circadian rhythm. Melatonin secretion declines with age, leading to different clinical consequences. This study investigated the melatonin levels among night vigil prayers, non-prayer late sleepers, and those with regular night sleep. Methods: A questionnaire including information about age, gender, education, and occupation was used to collect the demographic information of the participants. Melatonin was measured with two blood draws (23:00 to 24:00 and 9:00 to 10:00). Results: There was a significant difference between the night vigil prayers’ nocturnal and daily melatonin and the melatonin levels of the other two groups. There was no significant difference in the average daily serum melatonin levels between regular night sleepers and non-praying late sleepers (P=0.306). Moreover, a significant negative relationship was found between age and nocturnal melatonin (r=0.38, P&lt;0.0001) and between age and daily melatonin (r=0.25, P=0.02). Conclusion: Night vigil prayers had higher average nocturnal and daily serum melatonin levels than non-praying late sleepers and regular sleepers. Therefore, waking up at night accompanied by approaching Allah, prayer, supplication, and positive thoughts was related to release in melatonin.

Effects of Prepartum L-Tryptophan Supplementation on the Postpartum Performance of Holstein Cows.

The negative energy balance occurring in the periparturient period of cows will impede their health and postpartum performance. To target this issue, L-tryptophan was supplied to the prepartum cows. The results showed that L-tryptophan supplementation significantly increased the serum melatonin level and was accompanied with increases in SOD activity, IL-10 and colostrum IgA levels as well as decreases in MDA and IL-6 levels compared to the control cows. The incidence of postpartum diseases was significantly lower and the pregnancy rate was significantly higher in cows fed L-tryptophan than in the control group. A striking observation was that prepartum L-tryptophan supplementation not only improved the milk production but also the quality compared to the control cows. In general, supplementation with L-tryptophan in the prepartum period can improve the postpartum reproduction and lactation performance of cows to some extent.

Melatonin Mitigates Atrazine-Induced Renal Tubular Epithelial Cell Senescence by Promoting Parkin-Mediated Mitophagy.

The accumulation of senescent cells in kidneys is considered to contribute to age-related diseases and organismal aging. Mitochondria are considered a regulator of cell senescence process. Atrazine as a triazine herbicide poses a threat to renal health by disrupting mitochondrial homeostasis. Melatonin plays a critical role in maintaining mitochondrial homeostasis. The present study aims to explore the mechanism by which melatonin alleviates atrazine-induced renal injury and whether parkin-mediated mitophagy contributes to mitigating cell senescence. The study found that the level of parkin was decreased after atrazine exposure and negatively correlated with senescent markers. Melatonin treatment increased serum melatonin levels and mitigates atrazine-induced renal tubular epithelial cell senescence. Mechanistically, melatonin maintains the integrity of mitochondrial crista structure by increasing the levels of mitochondrial contact site and cristae organizing system, mitochondrial transcription factor A (TFAM), adenosine triphosphatase family AAA domain-containing protein 3A (ATAD3A), and sorting and assembly machinery 50 (Sam50) to prevent mitochondrial DNA release and subsequent activation of cyclic guanosine 5'-monophosphate-adenosine 5'-monophosphate synthase pathway. Furthermore, melatonin activates Sirtuin 3-superoxide dismutase 2 axis to eliminate the accumulation of reactive oxygen species in the kidney. More importantly, the antisenescence role of melatonin is largely determined by the activation of parkin-dependent mitophagy. These results offer novel insights into measures against cell senescence. Parkin-mediated mitophagy is a promising drug target for alleviating renal tubular epithelial cell senescence.

Combined Transcranial Doppler and Melatonin Levels to Predict Delayed Cerebral Ischemia After Subarachnoid Hemorrhage.

To investigate the early prediction value of transcranial Doppler ultrasound (TCD) combined with serum melatonin level for delayed cerebral ischemia (DCI) caused by subarachnoid hemorrhage (SAH). This paper is a prospective study. A total of 120 patients with SAH treated were included. The patients were divided into the DCI group (40 cases) and non-DCI group (80 cases) according to whether DCI occurred 14 days after SAH (DCI usually occurs 4 to 14d after bleeding). Baseline data, serum melatonin level, and TCD test results within 24hours after admission were compared between the 2 groups. Multivariate logistic analysis was used to analyze the factors affecting the occurrence of DCI after SAH. The value of serum melatonin level, middle cerebral artery mean blood flow velocity (MBFV) and their combination in predicting DCI in SAH patients was evaluated. Univariate analysis showed that there were statistically significant differences in the proportion of Fisher grade, Hunt-Hess grade, serum melatonin level, middle cerebral artery systolic blood flow velocity (Vs), MBFV and pulse index (PI) between the 2 groups ( P <0.05). Serum melatonin levels, middle cerebral artery Vs, MBFV, and PI in the DCI group were higher than those in non-DCI group. Logistic regression (LR) analysis showed that serum melatonin level (OR=1.796, 95% CI: 1.575-4.123) and middle cerebral artery MBFV (OR=3.279, 95% CI: 2.112-4.720] were the influencing factors for DCI in SAH patients ( P <0.05). Middle cerebral artery MBFV and serum melatonin levels were higher in patients with SAH complicated with DCI, and the combination of the 2 could provide a reference for early clinical prediction of DCI in patients with aneurysmal subarachnoid hemorrhage (aSAH).

Microbial Indoles: Key Regulators of Organ Growth and Metabolic Function.

Gut microbes supporting body growth are known but the mechanisms are less well documented. Using the microbial tryptophan metabolite indole, known to regulate prokaryotic cell division and metabolic stress conditions, we mono-colonized germ-free (GF) mice with indole-producing wild-type Escherichia coli (E. coli) or tryptophanase-encoding tnaA knockout mutant indole-non-producing E. coli. Indole mutant E. coli mice showed multiorgan growth retardation and lower levels of glycogen, cholesterol, triglycerides, and glucose, resulting in an energy deficiency despite increased food intake. Detailed analysis revealed a malfunctioning intestine, enlarged cecum, and reduced numbers of enterochromaffin cells, correlating with a metabolic phenotype consisting of impaired gut motility, diminished digestion, and lower energy harvest. Furthermore, indole mutant mice displayed reduction in serum levels of tricarboxylic acid (TCA) cycle intermediates and lipids. In stark contrast, a massive increase in serum melatonin was observed-frequently associated with accelerated oxidative stress and mitochondrial dysfunction. This observational report discloses functional roles of microbe-derived indoles regulating multiple organ functions and extends our previous report of indole-linked regulation of adult neurogenesis. Since indoles decline by age, these results imply a correlation with age-linked organ decline and levels of indoles. Interestingly, increased levels of indole-3-acetic acid, a known indole metabolite, have been shown to correlate with younger biological age, further supporting a link between biological age and levels of microbe-derived indole metabolites. The results presented in this resource paper will be useful for the future design of food intervention studies to reduce accelerated age-linked organ decline.

Intestinal melatonin levels and gut microbiota homeostasis are independent of the pineal gland in pigs.

Melatonin (MEL) is a crucial neuroendocrine hormone primarily produced by the pineal gland. Pinealectomy (PINX) has been performed on an endogenous MEL deficiency model to investigate the functions of pineal MEL and its relationship with various diseases. However, the effect of PINX on the gastrointestinal tract (GIT) MEL levels and gut microbiome in pigs has not been previously reported. By using a newly established pig PINX model, we detected the levels of MEL in the GIT by liquid chromatography-tandem mass spectrometry. In addition, we examined the effects of PINX on the expression of MEL synthesis enzymes, intestinal histomorphology, and the intestinal barrier. Furthermore, 16S rRNA sequencing was performed to analyze the colonic microbiome. PINX reduced serum MEL levels but did not affect GIT MEL levels. Conversely, MEL supplementation increased MEL levels in the GIT and intestinal contents. Neither PINX nor MEL supplementation had any effect on weight gain, organ coefficient, serum biochemical indexes, or MEL synthetase arylalkylamine N-acetyltransferase (AANAT) expression in the duodenum, ileum, and colon. Furthermore, no significant differences were observed in the intestinal morphology or intestinal mucosal barrier function due to the treatments. Additionally, 16S rRNA sequencing revealed that PINX had no significant impact on the composition of the intestinal microbiota. Nevertheless, MEL supplementation decreased the abundance of Fibrobacterota and increased the abundance of Actinobacteriota, Desulfobacterota, and Chloroflexi. We demonstrated that synthesis of MEL in the GIT is independent of the pineal gland. PINX had no influence on intestinal MEL level and microbiota composition in pigs, while exogenous MEL alters the structure of the gut microbiota.

The relationship between melatonin level, oxidative stress, fatigue and sleep disorders in multiple sclerosis patients

Aims: Our study aimed to investigate the relationship between oxidative stress and melatonin levels, sleep disturbances and fatigue in persons with MS (pwMS).&#x0D; Methods: The study included 50 pwMS and 30 healthy controls. Levels of serum melatonin, glutathione peroxidase (GPx), superoxide dismutase (SOD), and malondialdehyde (MDA) were measured in both groups. Persons with MS (pwMS) were evaluated using the extended disability status scale (EDDS) while Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale, insomnia severity index, fatigue severity scale and Beck depression scale were used for both groups.&#x0D; Results: Persons with MS (pwMS) exhibited significantly higher sleep disturbances (p