Metabolomic Shifts Following Play-Based Activity in Overweight Preadolescents.

BACKGROUND: Play-based activities can be a positive intervention to increase participation of overweight children. Metabolomics can reveal elemental shifts in the metabolome, lending to potential mechanistic explanations behind improvements in physiological systems. OBJECTIVE: To elucidate dose-response urinary metabolomic signature shifts in overweight preadolescents following four or eight weeks of supervised play-based activity versus a typical summer break control group. We hypothesized that eight weeks of activity would cause the greatest shift in the metabolites. STUDY DESIGN: Twenty-two recreationally active preadolescents (12 males, 10 females) were randomly assigned to a four-week (4w) or eight-week (8w) activity group or to a control group (C). Participants reported to the laboratory on two separate occasions during which descriptive characteristics were recorded and urine samples were obtained. Children in the 4w and 8w cohort were tested at the beginning and end of the four and eight weeks of a supervised play-based physical activity program where they were active for 6 hours a day, 5 days a week. Children in the C group were tested before and after eight weeks of an unsupervised summer break. RESULTS: A valid supervised partial least squares discriminant analysis model was obtained between post-exercise subjects in 8w and C (3 components, R2X = 0.332, R2Y = 0.976, Q2 = 0.091). The eight week intervention yielded significant metabolomic changes in several identified compounds. CONCLUSION: When compared to a typical unsupervised summer break, a supervised play-based intervention provides enough of a stimulus for a shift in the metabolome.

Effects of supervised exercise program on metabolic function in overweight adolescents.

BACKGROUND: Inactivity is a primary factor related to childhood obesity, yet aerobic exercise has been shown to prevent weight gain and improve fitness in adolescents. Moreover, children become less active during their summer break from school. This study compared the effects of 4 and 8 weeks of supervised summer activity versus an unsupervised summer break on metabolic function and fitness in adolescents. METHODS: Twenty-two adolescents were divided into 4-week (n=6, weight 48.1±14.9 kg, body fat 27.4±8.4%) and 8-week exercise groups (n=6, weight 43.4±10.9 kg, body fat 28.5±12.8%), that performed supervised, play-based physical activity, versus an age-matched 8 week control group that maintained their typical summer break (n=10, weight 41.7±10.0 kg, body fat 23.7±8.0%). Anthropometrics, resting energy expenditure (REE), resting heart rate (RHR) and peak aerobic capacity (VO(2peak)) were evaluated before and after the intervention (4 or 8 weeks). RESULTS: REE showed group differences in posttraining conditions (the 4-week group vs. the control group, 1220±169 vs. 1067±144 kcal/die, and the 8-week group vs. the control group, 1202±151 vs. 1067±144 kcal/die, P=0.047), but RHR decreased (pre-program vs. post program: 97±22 vs. 80±8 beat/min, P=0.001) and VO(2peak) significantly increased (pre-program vs. post program: 27.8±7.8 vs. 34.8±6.5 mL/kg/min, P=0.001) in the 8-week group compared to the control group. CONCLUSIONS: Eight weeks of supervised play-based activity increased REE and VO(2peak) in adolescents with concomitant decreases in RHR. These data suggest that this novel model of exercise prescription could be considered world-wide by clinicians to improve fitness base in adolescents and help to combat the growing epidemic of childhood obesity.

Effect of play-based summer break exercise on cardiovascular function in adolescents.

AIM: To compare the effects of 4 and 8 weeks of play-based, supervised exercise during summer break versus an unsupervised break on cardiovascular function in adolescent children. METHODS: Twenty-two subjects were divided into a 4-week exercise group (age 10.1 ± 1.3 years), an 8-week exercise group (age 9.4 ± 1.7 years) or a control group (age 10.0 ± 1.3 years). The activity groups participated in a supervised summer camp for 6 h/day, 5 days/week including a discontinuous play-based physical activity program and a healthy lifestyle, while the control group were told to keep their regular summer break routines. Anthropometrics, pulse wave velocity, augmentation index, blood pressure and peak oxygen consumption were evaluated before and after the intervention. RESULTS: Normalized augmentation index (75 beats/min) significantly decreased after 4 and 8 weeks in the active groups (p = 0.04) while pulse wave velocity showed no significant changes in all groups. Mean arterial pressure decreased (p = 0.003) and peak oxygen consumption increased (p = 0.001) significantly in the 8 week group. CONCLUSION: These data suggest that 8 weeks of supervised play-based activity yield several cardio-beneficial results in adolescents, which may act as a clinical prophylaxis throughout their lifetime.

Role of tissue digestion and extensive sperm search after microdissection testicular sperm extraction.

OBJECTIVE: To report the chance of sperm discovery in the laboratory when sperm were not identified in the operating room (OR). DESIGN: Clinical retrospective study. SETTING: Department of urology at a tertiary university hospital. PATIENT(S): A total of 1,054 men with nonobstructive azoospermia who underwent microdissection testicular sperm extraction. INTERVENTION(S): Preoperative and intraoperative parameters were analyzed relative to the chance of sperm identification using a tissue digestion protocol in the laboratory if no sperm were observed in the OR. MAIN OUTCOME MEASURE(S): Sperm retrieval, clinical pregnancy, and live birth rates. RESULT(S): Sperm were found in the OR in 52.5% of the 1,054 men. Of the 501 men for whom sperm were not identified by andrologists in the OR, sperm were found in the laboratory for an additional 35 (7%). On multivariable logistic regression analysis, the presence of germ cells intraoperatively was the only predictor of identifying sperm in the laboratory after tissue digestion. CONCLUSION(S): In men undergoing microdissection testicular sperm extraction, when sperm were not observed in the OR despite extensive mechanical processing, sperm were observed in the laboratory for 7% of the men. This information is valuable in counseling couples in the immediate postoperative period when no sperm were identified intraoperatively.

cAMP-dependent protein kinase regulates ubiquitin-proteasome-mediated degradation and subcellular localization of the nuclear receptor coactivator GRIP1.

Nuclear receptors and their coactivators are key regulators of numerous physiological functions. GRIP1 (glucocorticoid receptor-interacting protein) is a member of the steroid receptor coactivator family. Here, we show that GRIP1 is regulated by cAMP-dependent protein kinase (PKA) that induces its degradation through the ubiquitin-proteasome pathway. GRIP1 was down-regulated in transiently transfected COS-1 cells after treatment with 8-para-chlorophenylthio-cAMP or forskolin and 3-isobutyl-1-methylxanthine and in adrenocortical Y1 cells after incubation with adrenocorticotropic hormone. Pulse-chase experiments with transiently transfected COS-1 cells demonstrated that the half-life of GRIP1 was markedly reduced in cells overexpressing the PKA catalytic subunit, suggesting that activation of PKA increases the turnover of GRIP1 protein. The proteasome inhibitors MG132 and lactacystin abolished the PKA-mediated degradation of GRIP1. Using ts20 cells, a temperature-sensitive cell line that contains a thermolabile ubiquitin-activating E1 enzyme, it was confirmed that PKA-mediated degradation of GRIP1 is dependent upon the ubiquitin-proteasome pathway. Coimmunoprecipitation studies of COS-1 cells transfected with expression vectors encoding GRIP1 and ubiquitin using anti-GRIP1 and anti-ubiquitin antibodies showed that the ubiquitination of GRIP1 was increased by overexpression of PKA. Finally, we show that PKA regulates the intracellular distribution pattern of green fluorescent protein-GRIP1 and stimulates recruitment of GRIP1 to subnuclear foci that are colocalized with the proteasome. Taken together, these data demonstrate that GRIP1 is ubiquitinated and degraded through activation of the PKA pathway. This may represent a novel regulatory mechanism whereby hormones down-regulate a nuclear receptor coactivator.