Glycolytic and oxidative muscles under acute glucose supplementation differ in their metabolic responses to fatty acyl-CoA synthetase gene suppression / 한국영양학회지

Purpose@#Skeletal muscles display significant heterogeneity in metabolic responses, owing to the composition of metabolically distinct fiber types. Recently, numerous studies have reported that in skeletal muscles, suppression of genes related to fatty acid channeling alters the triacylglycerol (TAG) synthesis and switches the energy substrates. However, such responses may differ, depending on the type of muscle fiber. Hence, we conducted in vitro and animal studies to compare the metabolic responses of different types of skeletal muscle fibers to the deficiency of fatty acyl-CoA synthetase (Acsl)6, one of the main fatty acidactivating enzymes. @*Methods@#Differentiated skeletal myotubes were transfected with selected Acsl6 short interfering RNA (siRNA), and C57BL/6J mice were subjected to siRNA to induce Acsl6 deficiency. TAG accumulation and expression levels of insulin signaling proteins in response to acute glucose supplementation were measured in immortalized cell-based skeletal myotubes, oxidative muscles (OM), and glycolytic muscles (GM) derived from the animals. @*Results@#Under conditions of high glucose supplementation, suppression of the Acsl6 gene resulted in decreased TAG and glycogen synthesis in the C2C12 skeletal myotubes. The expression of Glut4, a glucose transporter, was similarly downregulated. In the animal study, the level of TAG accumulation in OM was higher than levels determined in GM. However, a similar decrease in TAG accumulation was obtained in the two muscle types in response to Acsl6suppression. Moreover, Acsl6 suppression enhanced the phosphorylation of insulin signaling proteins (Foxo-1, mTORc-1) only in GM, while no such changes were observed in OM. In addition, the induction ratio of phosphorylated proteins in response to glucose or Acsl6 suppression was significantly higher in GM than in OM. @*Conclusion@#The results of this study demonstrate that Acsl6 differentially regulates the energy metabolism of skeletal muscles in response to glucose supplementation, thereby indicating that the fiber type or fiber composition of mixed muscles may skew the results of metabolic studies.

Assertive Behavior in Asking Smokers Not to Smoke among Patients with Vascular Diseases

PURPOSE: The purpose of this study was to identify the assertive behavior of asking smokers not to smoke and investigate the factors related to assertive behavior in patients with vascular diseases. METHODS: Participants were 203 adult Korean patients with vascular diseases such as cerebral infarction and myocardial infarction. Data were collected using questionnaires that included the characteristics of secondhand smoke (SHS), secondhand smoke-related variables (Health belief model factors, health promotion model factors) and level of assertive behavior. Descriptive statistics, t-test, ANOVA and multiple regression using SPSS/WIN 18.0 were performed. RESULTS: Participants who never ask smokers not to smoke was 39.9%, whereas participants who always ask was 7.4%. There was a weak positive relationship between assertive behavior and susceptibility to disease (r=.18), severity of disease (r=.19), benefit of assertive behavior to SHS exposure (r=.10), barrier of assertive behavior to SHS exposure (r=.24), and self-rated health (r=.21) respectively. There was a moderate positive relationship between assertive behavior and self-efficacy of assertive behavior to SHS exposure (r=.49). Health belief model factors explained 15.7% variance and health promotion model factors explained 27.0% of assertive behavior. CONCLUSION: The findings of this study suggest that self-efficacy of assertive behavior to SHS exposure is a very important factor. Therefore the development of a program to foster self-efficacy of assertive behavior regarding SHS exposure in patients with vascular diseases is needed.

Effect of Hizikia Fusiforme Water Extracts on Mouse Immune Cell Activation

Hizikia fusiforme (sea weed fusiforme) has long been used for food source in this country. This study was performed to evalute the immunomodulative effects of Hizikia fusiforme (sea weed fusiforme) in mouse, using in vivo experiments. In vivo experiment, different concentration (0, 50, 500 mg/kg B.W.) of Hizikia fusiforme water extracts were orally administrated into mouse every other day for two weeks. The proliferation of mouse splenocytes, the production of three cytokines (IL-1beta, IL-6, TNF-alpha) secreted by activated macrophage. Splenocyte proliferation was enhanced in mouse orally administrated with 50 mg/kg B.W. and 500 mg/kg B.W. concentration compared to that of control group. Especially, the highest proliferation of spleoncyte was seen from the mouse orally administrated at the concentration of 50 mg/kg B.W. Also, the mouse of Hizikia fusiforme water extracts supplementation group in the both concentrations showed enhanced levels of cytokine production by activated peritoneal macrophages compared to those in control group. The highest level of cytokine (IL-1beta, IL-6, TNF-alpha) production was observed at 50 mg/kg B.W. supplementation group with LPS stimulation in all cases.