Melatonin Improves Glucose Homeostasis and Insulin Sensitivity by Mitigating Inflammation and Activating AMPK Signaling in a Mouse Model of Sleep Fragmentation.

Sleep fragmentation (SF) can increase inflammation and production of reactive oxygen species (ROS), leading to metabolic dysfunction. SF is associated with inflammation of adipose tissue and insulin resistance. Several studies have suggested that melatonin may have beneficial metabolic effects due to activating AMP-activated protein kinase (AMPK).

Association of insomnia and daytime napping with metabolic syndrome and its components in a Korean population: an analysis of data from the Korean Genome and Epidemiology Study.

Objectives: We investigated the association between metabolic syndrome (MetS) and the coexistence of insomnia and daytime napping, because limited data have been reported regarding this association.

Methods: The study population was 8,440 participants aged 40-65 years, who were from the Korean Genome and Epidemiology Study. Self-reported information on insomnia symptoms and nap duration was used to define exposure variables.

Oral Administration of Human-Gut-Derived Improves Sleep Architecture in Rats.

(1) Background: The human gut microbiome may regulate sleep through the gut-brain axis. However, the sleep-promoting effects of gut microbiota remain unclear. (2) Methods: We obtained sleep-wake profiles from 25 rats receiving ( group), 5 rats receiving ( group), 4 rats not receiving bacteria (No administration group), and 8 rats receiving extracellular vesicles (EV) (EV group) during the baseline, administration, and withdrawal periods.

Surface Active Salivary Metabolites Indicate Oxidative Stress and Inflammation in Obstructive Sleep Apnea.

Purpose: Obstructive sleep apnea (OSA), a highly prevalent and potentially serious sleep disorder, requires effective screening tools. Saliva is a useful biological fluid with various metabolites that might also influence upper airway patency by affecting surface tension in the upper airway. However, little is known about the composition and role of salivary metabolites in OSA.

Sleep Fragmentation Accelerates Carcinogenesis in a Chemical-Induced Colon Cancer Model.

Aims of this study were to test whether sleep fragmentation (SF) increased carcinogenesis and to investigate the possible mechanisms of carcinogenesis in a chemical-induced colon cancer model. In this study, eight-week-old C57BL/6 mice were divided into Home cage (HC) and SF groups. After the azoxymethane (AOM) injection, the mice in the SF group were subjected to SF for 77 days.

Coexistence of Moderate-to-Severe Obstructive Sleep Apnea and Inflammation Accelerates the Risk of Progression of Arterial Stiffness: A Prospective 6-Year Study.

Both obstructive sleep apnea (OSA) and inflammation have now been recognized as imposing substantial cardiometabolic risk. However, no prospective study has reported whether the coexistence of OSA and inflammation exacerbates the progressive arterial stiffening. Thus, the purpose of this study is to examine whether these conditions increase the risk of the progression of arterial stiffening.

A cancer cell-specific benzoxadiazole-based fluorescent probe for hydrogen sulfide detection in mitochondria.

The present work describes the design and biological applications of a novel colorimetric and fluorescence turn-on probe for hydrosulfide detection. The probe was designed to introduce hemicyanine as the fluorescent skeleton and 7-nitro-1,2,3-benzoxadiazole as the recognition site. The optical properties and responses of the probe towards HS, anions and some biothiols indicate an impressively high selectivity of the probe towards HS such that it can be effectively used as an indicator for monitoring the level of HS in living cells.

Exosome and Melatonin Additively Attenuates Inflammation by Transferring miR-34a, miR-124, and miR-135b.

The positive effects of mesenchymal stem cells (MSCs) are primarily activated through molecular secretions known as paracrine activity, which regulates the function of various cell types including immune cells. Accumulating evidence shows that exosomes of soluble factors released from MSCs are potential alternative agents for stem cell-based therapy, although the exact underlying mechanism has not been elucidated. The purpose of this study was to evaluate the potential effects of exosomes produced by adipose-derived MSCs and to examine the changes in anti-inflammatory genes in concurrence with the polarization of M2 macrophages in cellular models ex vivo.

Inhibition of Renal Stellate Cell Activation Reduces Renal Fibrosis.

Interstitial fibrosis is a common feature of chronic kidney disease, and platelet-derived growth factor receptor-β (PDGFR-β)-positive mesenchymal cells are reportedly the major source of scar-producing myofibroblasts. We had previously demonstrated that albumin and its derivative R-III (a retinol-binding protein-albumin domain III fusion protein) inhibited the transdifferentiation/activation of hepatic stellate cells (HSCs) to myofibroblasts and that R-III administration reduced liver fibrosis. In this study, we isolated cells (referred to as renal stellate cells, RSCs) from rat kidney tissues using the HSC isolation protocol and compared their morphological and biochemical characteristics with those of HSCs.

Biological effects of melatonin on human adipose‑derived mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are capable of differentiating into other cell types and exhibit immunomodulatory effects. MSCs are affected by several intrinsic and extrinsic signaling modulators, including growth factors, cytokines, extracellular matrix and hormones. Melatonin, produced by the pineal gland, is a hormone that regulates sleep cycles.

Untargeted metabolomics analysis of rat hippocampus subjected to sleep fragmentation.

Sleep fragmentation (SF) commonly occurs in several pathologic conditions and is especially associated with impairments of hippocampus-dependent neurocognitive functions. Although the effects of SF on hippocampus in terms of protein or gene levels were examined in several studies, the impact of SF at the metabolite level has not been investigated. Thus, in this study, the differentially expressed large-scale metabolite profiles of hippocampus in a rat model of SF were investigated using untargeted metabolomics approaches.

Environmental Benzopyrene Attenuates Stemness of Placenta-Derived Mesenchymal Stem Cells via Aryl Hydrocarbon Receptor.

The toxic effects of particulate matter have been linked to polycyclic aromatic hydrocarbons (PAHs) such as benzopyrene. PAHs are potent inducers of the aryl hydrocarbon receptor (AhR), which is an expressed nuclear receptor that senses environmental stimuli and modulates gene expression. Even though several studies have shown that the benzopyrene (BP) of chemical pollutants significantly impaired stem cell activity, the exact molecular mechanisms were not clearly elucidated.

Intermittent hypoxia promotes carcinogenesis in azoxymethane and dextran sodium sulfate-induced colon cancer model.

Intermittent hypoxia (IH), a characteristic of obstructive sleep apnea, is known to promote cancer progression and aggressiveness in mouse models. However, little is known regarding the effect of IH on cancer initiation. Here, the effect of IH on carcinogenesis was explored in azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon cancer models with three different protocols.

A pH-Responsive Glycyrrhetinic-Acid-Modified Small-Molecule Conjugate for NIR Imaging of Hepatocellular Carcinoma (HCC).

We report a glycyrrhetinic-acid (GA)-decorated small-molecule conjugate for pH-triggered near-infrared (NIR) fluorescence imaging of hepatocellular carcinoma (HCC). Our in vitro studies demonstrated that the conjugate, referred to as NIR-GA, was efficiently taken up by liver cancer cell lines such as HepG2 and Huh7 through an endocytic pathway mediated by GA receptors. As suggested by co-localization studies, NIR-GA mainly localized in the lysosome, where the acidic pH results in the activation of the fluorescent dye through H -triggered spirolactam ring opening to give strong fluorescence in the NIR region.

The co-existence of elevated high sensitivity C-reactive protein and homocysteine levels is associated with increased risk of metabolic syndrome: A 6-year follow-up study.

Accumulating evidence has revealed that both high sensitivity C-reactive protein (hsCRP) and homocysteine (HCY) are associated with increased risk of metabolic syndrome (MetS) and cardiovascular disease. However, it is unclear whether the coexistence of these conditions accelerates the risk of metabolic syndrome (MetS). We hypothesized that the combination of high sensitivity C-reactive protein (hsCRP) and homocysteine (HCY) levels could exacerbate the development of MetS in a large prospective cohort study.

Obstructive sleep apnoea is associated with progression of arterial stiffness independent of obesity in participants without hypertension: A KoGES Prospective Cohort Study.

Accumulating evidence shows that obstructive sleep apnoea (OSA) is associated with an increased risk of cardiovascular disease. However, there are no published prospective studies on the relationship between OSA and the progression of arterial stiffness. We hypothesised that OSA would increase the risk of arterial stiffness progression, independent of obesity.

Melatonin improves insulin resistance and hepatic steatosis through attenuation of alpha-2-HS-glycoprotein.

Melatonin plays an important role in regulating circadian rhythms. It also acts as a potent antioxidant and regulates glucose and lipid metabolism, although the exact action mechanism is not clear. The α2-HS-glycoprotein gene (AHSG) and its protein, fetuin-A (FETUA), are one of the hepatokines and are known to be associated with insulin resistance and type 2 diabetes.

Concurrent Presence of Obstructive Sleep Apnea and Elevated Homocysteine Levels Exacerbate the Development of Hypertension: A KoGES Six-year Follow-up Study.

Accumulating evidence has revealed that obstructive sleep apnea (OSA) and high homocysteine (Hcy) levels play important roles in the increased risk of hypertension and cardiovascular disease. We investigated whether the presence of elevated Hcy levels among individuals with OSA increase the risk of hypertension in a cohort study. A total of 1825 participants were selected from the cohort study.

Accelerated tumor growth under intermittent hypoxia is associated with hypoxia-inducible factor-1-dependent adaptive responses to hypoxia.

Mounting evidence has revealed a causative role of intermittent hypoxia (IH) in cancer progression in mouse models of obstructive sleep apnea (OSA), but most studies have focused on the effects of IH following tumor implantation using an exposure to single IH frequency. Thus, we aimed to investigate 1) the potential effect of IH on the initial tumor growth in patients with OSA without an interaction with other mechanisms induced by IH in mice and 2) the influence of the IH frequency on tumor growth, which were tested using pre-conditioning with IH (Pre-IH) and 2 different IH frequencies, respectively. Pre-IH was achieved by alternatively maintaining melanoma cells between normoxia (10 min, 21% O) and hypoxia (50 min, 1% O) for 7 days (12 cycles per day) before administering them to mice.

Overlap syndrome of COPD and OSA in Koreans.

Overlap syndrome of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) leads to increased morbidity and mortality. There have been no reports available on the overlap syndrome for Koreans. Our primary aim was to identify prevalence and predictors of the overlap syndrome in Koreans.

Concurrent presence of inflammation and obstructive sleep apnea exacerbates the risk of metabolic syndrome: A KoGES 6-year follow-up study.

Obstructive sleep apnea (OSA) leads to multiple end-organ morbidities that are mediated by the cumulative burden of oxidative stress and inflammation. Both OSA and inflammation play key roles in increased risk of cardiovascular disease (CVD). Thus, we hypothesized that the combination of inflammation and OSA could accelerate the development of metabolic syndrome (MetS) in a large cohort study.

The association between irritable bowel syndrome and the coexistence of depression and insomnia.

Objective: The individual occurrence of depression or insomnia is a risk factor for irritable bowel syndrome (IBS), but few researchers have evaluated the association between comorbid depression and insomnia and IBS. The aim of the present study is to explore the relationship between IBS and the coexistence of depression and insomnia in a Korean population-based cohort study.

Methods: A total of 3429 individuals who were enrolled in the Korean Genome and Epidemiology Study were analysed.

Obstructive Sleep Apnea Is Associated with Elevated High Sensitivity C-Reactive Protein Levels Independent of Obesity: Korean Genome and Epidemiology Study.

Obstructive sleep apnea syndrome (OSA) has been recognized as a common health problem, and increasing obesity rates have led to further remarkable increases in the prevalence of OSA, along with more prominent cardiovascular morbidities. Though previous studies have reported an independent relationship between elevated high sensitivity C-reactive protein (hsCRP) levels and OSA, the issue remains controversial owing to inadequate consideration of obesity and various confounding factors. So far, few population based studies of association between OSA and hsCRP levels have been published.

Association of Sasang Constitutional Types with Incident Hypertension: A 12-Year Follow-Up Study.

Objectives: Sasang constitutional types (SCTs) are four distinct classifications of people based on physiologic and physical characteristics. The different types have been reported to have different disease susceptibility, but there are no studies reporting the association of SCT and hypertension (HTN) over a long-term follow-up period. This study prospectively investigated the association between SCT and incidence of HTN.