Shriners Hospitals for Children - Galveston

Abstract: Background The catecholamine-mediated hypermetabolic response to severe burns causes increased energy expenditure and muscle-protein catabolism. We hypothesized that blockade of β-adrenergic stimulation with propranolol would decrease resting energy expenditure and muscle catabolism in patients with severe burns. Methods Twenty-five children with acute and severe burns (more than 40 percent of total body-surface area) were studied in a randomized trial. Thirteen received oral propranolol for at least two weeks, and 12 served as untreated controls. The dose of propranolol was adjusted to decrease the resting heart rate by 20 percent from each patient's base-line value. Resting energy expenditure and skeletal-muscle protein kinetics were measured before and after two weeks of beta-blockade (or no therapy, in controls). Body composition was measured serially throughout hospitalization. Results Patients in the control group and the propranolol group were similar with respect to age, weight, percentage of tota...

Abstract: The present study was designed to determine whether consumption of an oral essential amino acid-carbohydrate supplement (EAC) before exercise results in a greater anabolic response than supplementa...

Abstract: Brown adipose tissue (BAT) has attracted scientific interest as an antidiabetic tissue owing to its ability to dissipate energy as heat Despite a plethora of data concerning the role of BAT in glucose metabolism in rodents, the role of BAT (if any) in glucose metabolism in humans remains unclear To investigate whether BAT activation alters whole-body glucose homeostasis and insulin sensitivity in humans, we studied seven BAT-positive (BAT+) men and five BAT-negative (BAT−) men under thermoneutral conditions and after prolonged (5–8 h) cold exposure (CE) The two groups were similar in age, BMI, and adiposity CE significantly increased resting energy expenditure, whole-body glucose disposal, plasma glucose oxidation, and insulin sensitivity in the BAT+ group only These results demonstrate a physiologically significant role of BAT in whole-body energy expenditure, glucose homeostasis, and insulin sensitivity in humans, and support the notion that BAT may function as an antidiabetic tissue in humans

Abstract: Background: The hypermetabolic response to severe burn is characterized by muscle protein catabolism. Current opinion states that the hypermetabolic state resolves soon after complete wound closure. Clinically, we have witnessed that burned children appear to be hypermetabolic and catabolic long after full healing of their wounds. Our goal in this study was to determine scientifically if burn-associated hypermetabolism persists after full wound healing. Methods: To determine the duration of muscle catabolism and systemic hypermetabolism after severe burn in children, patients with > 40% total body surface area burns were enrolled in a prospective, longitudinal study; resting energy expenditure was measured by indirect calorimetry, muscle protein kinetics were determined by using stable isotopic methodology, and body composition was measured by dual-energy x-ray absorptiometry imaging. Data were collected at 6, 9, and 12 months after injury. Results: The mean total body surface area burned was 65% ± 13%, and the mean age was 7.6 ± 1.5 years. Resting energy expenditure was elevated above the predicted age-matched levels from the Harris-Benedict equation and incrementally declined throughout the 12-month study. The net protein balance and lean mass reflected catabolic persistence at 6 and 9 months after severe burn. Between 9 and 12 months, protein breakdown decreased, net protein balance improved, and lean body mass increased. Conclusions: In severely burned children, hypermetabolism and catabolism remain exaggerated for at least 9 months after injury. This suggests that therapeutic attempts to manipulate the catabolic and hypermetabolic response to severe injury should be continued long after injury. (Surgery 2000;128:312-9.)

Abstract: We recently demonstrated that muscle protein synthesis was stimulated to a similar extent in young and elderly subjects during a 3-h amino acid infusion. We sought to determine if a more practical ...