Uridine is postulated to participate in the development of insulin resistance. Since exercise is an effective tool in the treatment of insulin resistance it appeared justified to assess the impact of maximal exercise on plasma uridine and insulin sensitivity indices (e.g. insulin and HOMA-IR) in healthy subjects. The study included forty-four healthy males (18.5±2.92 years, VO2 max 50.2±6.26 ml kg-1 min-1). Subjects performed a single maximal exercise on a bicycle ergometer. Blood samples were taken three times: immediately before exercise, immediately after exercise and at the 30th min of rest. Uridine concentrations were determined in the whole blood using high-performance liquid chromatography. Serum insulin levels were measured by a specific ELISA method. Insulin sensitivity was assessed by homeostasis model assessment method (HOMA-IR). A maximal exercise-induced increase in the concentration of uridine correlated with post-exercise increases in insulin levels and HOMA-IR. Our results indicate a relationship between the concentration of uridine in the blood and indicators of insulin sensitivity in healthy subjects. We are the first to demonstrate that a maximal exercise-induced increase in the concentration of uridine is correlated with post-exercise increases in insulin levels and HOMA-IR in healthy subjects. It appears that uridine may be an indicator of insulin resistance., W. Dudzinska, ... [et al.]., and Obsahuje seznam literatury
Common alimentary obesity frequently occurs on a polygenic basis as a typical lifestyle disorder in the developed countries. It is associated with characteristic complex metabolic changes, which are the cornerstones for future metabolic syndrome development. The aims of our study were 1) to determine the incidence of metabolic syndrome (based on the diagnostic criteria defined by the International Diabetes Federation for children and adolescents) in Czech obese children, 2) to evaluate the incidence of insulin resistance according to HOMA-IR and QUICKI homeostatic indexes in obese children with and without metabolic syndrome, and 3) to consider the diagnostic value of these indexes for the early detection of metabolic syndrome in obese children. We therefore performed anthropometric and laboratory examinations to determine the incidence of metabolic syndrome and insulin resistance in the group of 274 children with obesity (128 boys and 146 girls) aged 9-17 years. Metabolic syndrome was found in 102 subjects (37 %). On the other hand, the presence of insulin resistance according to QUICKI <0.357 was identified in 86 % and according to HOMA-IR >3.16 in 53 % of obese subjects. This HOMA-IR limit was exceeded by 70 % children in the MS(+) group, but only by 43 % children in the MS(–) group (p<0.0001). However, a relatively high incidence of insulin resistance in obese children without metabolic syndrome raises a question whether the existing diagnostic criteria do not falsely exclude some cases of metabolic syndrome. On the basis of our results we suggest to pay a preventive attention also to obese children with insulin resistance even if they do not fulfill the actual diagnostic criteria for metabolic syndrome., D. Pastucha, ... [et al.]., and Obsahuje seznam literatury