α-Tocopherol adipose tissue stores are depleted after burn injury in pediatric patients

Abstract

Background: We previously showed that thermal injury depletes plasma vitamin E in pediatric burn patients; however, plasma changes may reflect immediate alterations in vitamin E nutriture. Adipose tissue a-tocopherol concentrations are generally accepted to reflect long-term vitamin E status. Objective: To test the hypothesis that thermal injury depletes body stores of vitamin E, a-tocopherol concentrations were measured in adipose tissue samples. Design: Pediatric patients (n = 8) were followed up to 1 y after burn injury. Surgically obtained samples were collected at various intervals and stored at 280°C in a biorepository. a-and c-Tocopherols, cholesterol, and triglycerides were measured in the same tissue aliquot. Results: During the first week after injury, adipose tissue a-tocopherol concentrations were within the expected normal range of 199 6 40 nmol/g adipose tissue but were substantially lower at weeks 2 and 3 (133 6 13 and 109 6 8 nmol/g adipose tissue, respectively). Individual rates of decrease, estimated by linear regression, showed that adipose tissue a-tocopherol decreased by an average of 6.1 6 0.6 nmol/g daily. During the first month after injury, adipose tissue triglyceride concentrations also decreased, whereas no changes in cholesterol concentrations occurred. Conclusions: These data emphasize that the burn injury experienced by these pediatric patients altered their metabolism such that vitamin E status diminished during the month after injury. Further studies are needed to evaluate the mechanism and consequences of the observed vitamin E depletion. This trial was registered at clinicaltrials.gov as NCT00675714.Am J Clin Nutr 2010;92:1378-84.

Vitamine E et physiologie du tissu adipeux

“…Cette stabilite (de l'ordre de plusieurs annees) fait que ce stock est faiblement mobilisable lors de l'arrêt de supplementation. Cependant, il a ete recemment montre que la vitamine E presente dans le tissu adipeux peutêtre tres rapidement (quelques semaines) mobilisable dans des conditions particulieres d'hypermetabolisme, qui apparaît suite a des brûlures severes chez l'enfant (Traber et al, 2010).…”

Micronutrient Requirements of Pediatric Patients With Burns

“…The study found decreasing levels of α-tocopherol in 5 of 8 subjects, with an average decrease of α-tocopherol of 6.1 ± 0.6 μmol/g per day and levels as low as 55% of the original concentrations 3 weeks after injury despite consuming vitamin E at or above the RDA. 9 Insufficient α-tocopherol levels were still seen a month after injury. 9 Although decreased triglyceride levels were also seen in the adipose tissues of these patients, vitamin E levels decreased more significantly, likely due to the use by other tissues during a period of high 184 TOPICS IN CLINICAL NUTRITION/APRIL-JUNE 2013 oxidative stress.…”

“…9 Insufficient α-tocopherol levels were still seen a month after injury. 9 Although decreased triglyceride levels were also seen in the adipose tissues of these patients, vitamin E levels decreased more significantly, likely due to the use by other tissues during a period of high 184 TOPICS IN CLINICAL NUTRITION/APRIL-JUNE 2013 oxidative stress. 9 The authors determined, based on the tissue biopsies, that the average daily loss of adipose cells was approximately 6 nmol/kg and estimated that a 24-kg child with a burn could be losing as much as 5 mg of α-tocopherol per day.…”

Ischemia-Reperfusion Injury

“…By examining the sequential events occurring in IRI, logical interventions are apparent and a combination of techniques is likely to be successful. Aside from the mechanical preconditioning maneuvers which are relatively risk free, the pharmacological strategies worthy of consideration include, among others, sodium nitrite, 6,23 CD47 antibody, 18,22 hydrogen sulfide, 24Y28 Diannexin, 9 poloxamer 188, 15 desferrioxamine, 57 >-tocopherol, 58 and other antioxidants and streptokinase. 46 A combination of mechanical preconditioning, ROS neutralization, NO stimulation, and an antithrombotic would constitute a logical sequence of IRI combating maneuvers.…”