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. Data on waist circumference (WC), blood pressure (BP), and fasting blood glucose (FBG), triglyceride (TG), and high-density lipoprotein cholesterol levels in blood were used to define MetS. Multivariate logistic regression analysis was performed to obtain odds ratio (OR) and 95% confidence interval (CI). RESULTS: In multivariate logistic regression analysis, the coexistence of insomnia and napping was not significantly associated with MetS. However, the insomnia and non-napping group showed higher ORs of high TG (OR, 1.19; 95% CI, 1.02 to 1.39) and high BP (OR, 1.28; 95% CI, 1.10 to 1.49) than the non-insomnia and non-napping group. The combination of non-insomnia and napping and that of insomnia and napping showed higher ORs of high TG (OR, 1.13; 95% CI, 1.00 to 1.29) and high FBG (OR, 1.59; 95% CI, 1.14 to 2.21), respectively. In analyses of insomnia symptoms, only the combination of difficulty in maintaining sleep (DMS) and non-napping showed a higher OR for MetS (OR, 1.25; 95% CI, 1.03 to 1.52) than the non-DMS and non-napping group. CONCLUSIONS: Individuals with insomnia, particularly those who do not take naps, were disproportionately likely to have MetS components, especially TG or BP. Information on these variables may help predict individuals' vulnerability to specific MetS components.

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). However, it is unclear whether melatonin affects the AMPK signaling pathway in SF-induced metabolic dysfunction. Therefore, we hypothesize that SF induces metabolic impairment and inflammation in white adipose tissue (WAT), as well as altered intracellular homeostasis. We further hypothesize that these conditions could be improved by melatonin treatment. We conducted an experiment using adult male C57BL/6 mice, which were divided into three groups: control, SF, and SF with melatonin treatment (SF+Mel). The SF mice were housed in SF chambers, while the SF+Mel mice received daily oral melatonin. After 12 weeks, glucose tolerance tests, insulin tolerance tests, adipose tissue inflammation tests, and AMPK assessments were performed. The SF mice showed increased weight gain, impaired glucose regulation, inflammation, and decreased AMPK in WAT compared to the controls. Melatonin significantly improved these outcomes by mitigating SF-induced metabolic dysfunction, inflammation, and AMPK downregulation in adipose tissue. The therapeutic efficacy of melatonin against cardiometabolic impairments in SF may be due to its ability to restore adipose tissue homeostatic pathways.

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. SF was accomplished in a sleep fragmentation chamber. In the second protocol, mice were divided into 2% dextran sodium sulfate (DSS)-treated, HC, and SF groups and were exposed to the HC or SF procedures. Immunohistochemical and immunofluorescent stainings were conducted to determine the level of 8-OHdG and reactive oxygen species (ROS), respectively. Quantitative real-time polymerase chain reaction was used to assess the relative expression of inflammatory and ROS-generating genes. The number of tumors and average tumor size were significantly higher in the SF group than in the HC group. The intensity (%) of the 8-OHdG stained area was significantly higher in the SF group than in the HC group. The fluorescence intensity of ROS was significantly higher in the SF group than the HC group. SF accelerated cancer development in a murine AOM/DSS-induced model of colon cancer, and the increased carcinogenesis was associated with ROS- and oxidative stress-induced DNA damage.

Idealness of k-wise intersecting families.

A clutter is k-wise intersecting if every k members have a common element, yet no element belongs to all members. We conjecture that, for some integer k ≥ 4 , every k-wise intersecting clutter is non-ideal. As evidence for our conjecture, we prove it for k = 4 for the class of binary clutters. Two key ingredients for our proof are Jaeger's 8-flow theorem for graphs, and Seymour's characterization of the binary matroids with the sums of circuits property. As further evidence for our conjecture, we also note that it follows from an unpublished conjecture of Seymour from 1975. We also discuss connections to the chromatic number of a clutter, projective geometries over the two-element field, uniform cycle covers in graphs, and quarter-integral packings of value two in ideal clutters.

Physicochemical Properties and Drivers of Liking and Disliking for Cooked Rice Containing Various Types of Processed Whole Wheat.

For utilization of whole wheat (WW) in cooked rice products, WW was processed by four different methods (steeping (S_WW), milling (M_WW), enzymatic treatment (E_WW), and passing through a roll mill (1 mm) (R_WW)). Additionally, the physicochemical properties of cooked rice containing various processed wheat were investigated. The hardness of the cooked rice decreased significantly with R_WW and E_WW compared to WW. As a result of a consumer acceptance test, the cooked rice samples containing M_WW and E_WW with high liking scores frequently included 'chewiness' as a reason for liking, and the cooked rice with WW and S_WW was mentioned as being 'too hard' as a reason for disliking. The cooked rice with R_WW, which had the lowest liking score, was mentioned as having appearance characteristics such as 'husk', 'clumpy appearance', and 'messy appearance' as reasons for disliking. The overall results of this study suggest the inclusion of M_WW or E_WW with cooked rice considering health-related benefits and consumer acceptability.

Comparison of Physicochemical Properties and Metabolite Profiling Using 1H NMR Spectroscopy of Korean Wheat Malt.

The objective of this study was to compare the physicochemical, enzymatic, and metabolic properties of two control wheat malts imported from Germany and the US to those of malts made from three Korean wheat varieties: Triticumaestivum L., var. Anzunbaengi, Jokyung, and Keumkang. The qualities and enzyme activities of the Korean wheat malts were generally similar to those of the control wheat malts. The Korean wheat malts had slightly lower diastatic power and enzyme activities related to saccharification. The analysis of metabolites in the wheat malt samples was performed using 1H nuclear magnetic resonance (NMR) metabolomics, which identified 32 metabolites that differed significantly among the samples. Most amino acids and lipids were more abundant in the Korean wheat malts than in the control wheat malts. These differences among malts could influence the quality and flavor of wheat beers. Further brewing studies are necessary to identify the association between beer quality and individual malt metabolites.

Characteristics of Bread Made of Various Substitution Ratios of Bran Pulverized by Hammer Mill or Jet Mill.

The physicochemical and antioxidant properties of dough and bread were measured in wheat flours substituted with two types of bran (HMB: bran pulverized by a hammer mill and JMB: bran pulverized by a jet mill) at various ratios (0%, 5%, 10%, 15%, 20%, and 25%) of substitution. The particle size of hammer mill bran (HMB) (119.71 µm) was larger than that of jet mill bran (JMB) (25.78 µm). Wheat flours substituted with HMB contained more total dietary fiber than those with JMB. A significant increase of water absorption and dough development time in Mixolab® analysis was observed depending on the level of HMB or JMB substitution. The breads made with HMB or JMB (5% or 10%) showed a higher specific volume and lower crumb hardness than the control bread. However, breads made with ≥15% HMB or JMB had a decreased specific volume and increased crumb hardness. Overall, breads made with wheat flour substituted with 5%-10% HMB or JMB were of a higher bread quality and had more antioxidant properties.

Antiobesity Effect of Tricin, a Methylated Cereal Flavone, in High-Fat-Diet-Induced Obese Mice.

The antiobesity potential of tricin, a methylated cereal flavonoid, was examined using a high-fat-diet-induced obese mice model. The body weight ( P < 0.01) and body fat mass ( P < 0.05) were significantly decreased in the high-dose tricin supplementation group (TH: 200 mg/kg diet) in comparison to the high fat diet control group (CON) after a 12-week feeding trial. The serum (60.9 ± 2.09 mg/dL) and hepatic triglyceride levels (45.3 ± 4.42 nmol/mg protein) in the TH group were significantly decreased in comparison to the CON group (78.3 ± 5.09 mg/dL, 76.3 ± 8.10 nmol/mg protein), respectively. This antiobesity effect was attributed to a decrease in the expression of lipogenic markers crucial for fat synthesis in the liver (fatty acid synthase, stearoyl-CoA desaturase 1, elongation of long-chain fatty acids family member 6, glycerol-3-phosphate acyltransferase, and diglyceride acyltransferase) and suppressed expression of transcription factors associated with adipocyte differentiation (peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding protein α). These lipid-lowering effects are mediated by the activation of adenosine 5'-monophosphate-activated protein kinase.

Enzyme and high pressure assisted extraction of tricin from rice hull and biological activities of rice hull extract.

Enzymatic hydrolysis was performed in conjunction with high hydrostatic pressure (HPP) treatment to extract tricin from rice hull. Enzymatic hydrolysis performed with Celluclast (0.5%, w/w) prior to HPP (500 MPa) treatment yielded maximum tricin content (32.9 mg/kg rice hull). The tricin content obtained by conventional solvent extraction and HPP treatment alone were 14.7 and 19.7 mg/kg rice hull, respectively. The rice hull extract containing tricin displayed antioxidant, anti-inflammatory, and antiadipogenic activities. The efficacy of rice hull extract obtained by either HPP or combination of enzymatic hydrolysis and HPP treatments was significantly greater than that of extract prepared by traditional solvent extraction.