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Background: Effects of endurance training on adipose insulin sensitivity in association with body composition, circulating adipokines, and markers of inflammation have been studied less in young Asian subjects.Methods: Adipose insulin sensitivity/resistance was compared between 170 female Japanese collegiate athletes and 311 nonathletes (18–24 years), who underwent measurements of serum adipokines, markers of insulin sensitivity, inflammation, and dual-energy X-ray absorptiometry. Two separate subsamples of two groups of women underwent either a 75-gram oral glucose tolerance test or a standardized meal test, but not both.Results: As compared with nonathletes, athletes, characterized by higher skeletal muscle mass and lower percentage of body fat (both P < 0.001), had lower adipose insulin resistance (IR) (a product of fasting insulin and nonesterified fatty acid (NEFA) and lower leptin/adiponectin ratio (both P < 0.001). Although athletes had lower postmeal/postglucose insulinemia (P = 0.009 and 0.01, respectively), the two groups did not differ in postmeal percentage NEFA suppression and postmeal/postglucose glycemia, suggesting increased insulin sensitivity in adipose tissue and skeletal muscle, respectively. Serum leptin (P < 0.001) and tumor necrosis factor-α (P = 0.01) were lower in athletes, whereas adiponectin and homeostasis model assessment IR did not differ.Conclusions: Endurance training was associated with increased insulin sensitivity in adipose tissue as well as skeletal muscle without changes in circulating adiponectin even in young, normal-weight Japanese women.

ObjectiveInflammatory markers are elevated in insulin resistance (IR) and diabetes. We tested whether serum orosomucoid (ORM) is associated with postload glucose, β-cell dysfunction and IR inferred from plasma insulin kinetics during a 75 g oral glucose tolerance test (OGTT).Research design and methods75 g OGTTs were performed with multiple postload glucose and insulin measurements over a 30–120 min period in 168 non-obese Japanese women (aged 18–24 years). OGTT responses, serum adiponectin and high-sensitivity C reactive protein (hsCRP) were cross-sectionally analyzed by analysis of variance and then Bonferroni’s multiple comparison procedure. Stepwise multivariate linear regression analyses were used to identify most important determinants of ORM.ResultsOf 168 women, 161 had normal glucose tolerance. Postload glucose levels and the area under the glucose curve (AUCg) increased in a stepwise fashion from the first through the third ORM tertile. In contrast, there was no or modest, if any, association with fat mass index, trunk/leg fat ratio, adiponectin, hsCRP, postload insulinemia, the Matsuda index and homeostasis model assessment IR. In multivariable models, which incorporated the insulinogenic index, the Matsuda index and HOMA-IR, 30 min glucose (standardized β: 0.517) and AUCg (standardized β: 0.495) explained 92.8% of ORM variations.ConclusionsElevated circulating orosomucoid was associated with elevated 30 min glucose and glucose excursion in non-obese young Japanese women independently of adiposity, IR, insulin secretion, adiponectin and other investigated markers of inflammation. Although further research is needed, these results may suggest a clue to identify novel pathways that may have utility in monitoring dysglycemia within normal glucose tolerance.

The control of blood pressure (BP) is important in the prevention of cardiovascular diseases. This study was conducted to evaluate the effect of a dietary educational program for free-living, high-normal, and stage 1 or 2 hypertensive men. The participants were volunteers aged 40-75 years who agreed to the intervention. They were divided into two groups: 39 men for the intervention group and 32 men for the control group. BP, urinary sodium and potassium excretion, dietary and lifestyle data, and nonfasting venous blood sample were collected at baseline and after the intervention period. The intervention was designed to decrease sodium level with an emphasis on a decrease in the consumption of salted foods and to increase potassium level with an emphasis on an increase in the consumption of fruit and vegetables through cooking instructions and self-monitoring of the diet. At the baseline, there were no significant differences observed between the groups, except the diastolic BP. In the intervention group, a greater decrease in the urinary sodium-to-potassium excretion ratio was observed, compared with the control group (net difference 0.6, P = .029). The systolic and diastolic BP (mm Hg) decreased in the intervention group (149.0-143.0, P = .073; 93.0-87.0, P = .002), but no changes were observed in the control group (145.0-143.0, P = .231; 84.9-85.3, P = .381). In the intervention group, the urinary sodium-to-potassium excretion ratio was significantly improved by focusing on cooking instructions and self-monitoring of the diet.