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PurposeTo compare the effects of endurance exercise performed in the morning and evening on inflammatory cytokine responses in young men.MethodsFourteen healthy male participants aged 24.3 ± 0.8 years (mean ± standard error) performed endurance exercise in the morning (0900–1000 h) on one day and then in the evening (1700–1800 h) on another day with an interval of at least 1 week between each trial. In both the morning and evening trials, the participants walked for 60 minutes at approximately 60% of the maximal oxygen uptake () on a treadmill. Blood samples were collected to determine hormones and inflammatory cytokines at pre-exercise, immediately post exercise, and 2 h post exercise.ResultsPlasma interleukin (IL)-6 and adrenaline concentrations were significantly higher immediately after exercise in the evening trial than in the morning trial (P < 0.01, both). Serum free fatty acids concentrations were significantly higher in the evening trial than in the morning trial at 2 h after exercise (P < 0.05). Furthermore, a significant correlation was observed between the levels of IL-6 immediately post-exercise and free fatty acids 2 h post-exercise in the evening (r = 0.68, P < 0.01).ConclusionsThese findings suggest that the effect of acute endurance exercise in the evening enhances the plasma IL-6 and adrenaline concentrations compared to that in the morning. In addition, IL-6 was involved in increasing free fatty acids, suggesting that the evening is more effective for exercise-induced lipolysis compared with the morning.

BACKGROUND/OBJECTIVES: Postprandial hyperglycemia increases the risks of development of type 2 diabetes and cardiovascular diseases. The purpose of this study was to determine whether a 3-day low-carbohydrate/high-fat diet (LC/HFD) alters postprandial plasma glucose and incretin levels during oral glucose tolerance test (OGTT) in healthy men. SUBJECTS/METHODS: Nine healthy young men (age (mean±s.e.), 27±1 years; body mass index, 22±1 kg/m 2 ) consumed either a normal diet (ND: energy from B22% fat) or a LC/HFD (energy from B69% fat) for 3 days each. The total energy intake from each diet was similar. An OGTT was performed after each 3-day dietary intervention. Postprandial plasma glucose, insulin, free fatty acid and glucagon-like peptide-1 (GLP-1) levels were determined at rest and during the OGTT. RESULTS: Plasma glucose levels and incremental area under the curve during the OGTT were significantly higher in the LC/HFD trial than in the ND trial (P ¼ 0.024). In addition, increase in GLP-1 levels was significantly higher in the LC/HFD trial than in the ND trial (P ¼ 0.025). The first-phase insulin secretion indexes were significantly lower in the LC/HFD trial than in the ND trial (Po0.041).CONCLUSIONS: These results demonstrate that even short-term LC/HFD increased postprandial plasma glucose and GLP-1 levels in healthy young men. A decrease in first-phase insulin secretion may partially contribute to the short-term LC/HFD-induced increase in postprandial plasma glucose levels. Keywords: postprandial hyperglycemia; incretin; impaired glucose tolerance; glucose-dependent insulinotropic polypeptide INTRODUCTION Postprandial hyperglycemia is a condition of high blood glucose level after eating a meal, and is an effective predictor of mortality from all causes and cardiovascular diseases (CVD) as well as the risk of developing type 2 diabetes.1-3 Furthermore, decreasing postprandial hyperglycemia with medications reduces the risks of developing CVD and type 2 diabetes. [4][5][6] One of the factors explaining the association between postprandial hyperglycemia and the development of CVD and type 2 diabetes is the resulting acute fluctuation in blood glucose levels. Interestingly, acute fluctuation in blood glucose levels suppresses endotheliumdependent vasodilation, 7 and increases levels of interleukin-6, tumor necrosis factor-a 8 and platelet hyperaggregability 9 in healthy men; all these parameters have been associated with the development of CVD. Therefore, it is important to elucidate the factors that elicit postprandial hyperglycemia for the prevention of both CVD and type 2 diabetes.A low-carbohydrate/high-fat diet (LC/HFD) has a key role in the development of postprandial hyperglycemia. Short-term exposure (1-11 days) to LC/HFD decreases carbohydrate oxidation 10-16 and increases endogenous glucose production. 10,17 In addition, shortterm LC/HFD (3-5 days) decreases insulin sensitivity, as measured using the hyperinsulinemic-euglycemic glucose clamp 18,19 and the intravenous glucose tolerance test. 20 However...

Abstract. The 13 C-breath test has been used to clinically evaluate gastric emptying. However, this method has not been sufficiently validated in experimental animals. The present study aimed to establish a simple and noninvasive 13 C-breath-test system in Sprague-Dawley male rats. After fasting, rats were orally administered Racol containing 13 C-acetic acid and housed in a desiccator. The expired air in the chamber was collected in a breath-sampling bag using a tube and aspiration pump. The level of 13 CO 2 in the expired air was measured using an infrared spectrometer at appropriate intervals for 120 min. During this period, the rate of 13 CO 2 excretion increased, peaked, and decreased thereafter. The maximum concentration (C max ) and area under the curve (AUC 120 min ) of 13 CO 2 excretion increased in volume-and dose-dependent manners. The time taken to reach the maximum concentration (T max ) of 13 CO 2 excretion increased as the volume increased, but was not affected by the dose of 13 C-labeled acetic acid. Metoclopramide dosedependently increased the C max and shortened T max of 13 CO 2 excretion compared with those of the control rats, whereas the AUC 120 min was not affected. These results confirm that this simple method can successfully evaluate gastric emptying. Moreover, this system is suitable for investigating additional physiological functions using other labeled compounds.

A previously undescribed larval settlement-inducing protein was purified from adult extracts of the barnacle, Balanus amphitrite (=Amphibalanus amphitrite). Results of SDS-PAGE indicated that the relative molecular mass of the protein in reduced and denatured form is 31,600 +/- 500 kDa, and that it is distinct from the Settlement Inducing Protein Complex (SIPC) which has previously been determined as a larval settlement-inducing pheromone. The N-terminal 33-residue sequence of the intact protein showed no similarity with previously reported proteins in the EMBL/Genbank/DDBJ databases. The purified protein at a concentration of 10 microg ml(-1) induced approximately four times more larval settlement than the control (filtered natural seawater). In addition, results of the assay using both 24-well polystyrene plates and agarose gels indicated that this protein is probably released into seawater and attracts cypris larvae. These results suggest that the purified protein is a waterborne type pheromone which induces settlement of larvae of B. amphitrite.