Gene Expression Patterns in Skeletal Muscle of Thermally Injured Children Treated with Oxandrolone

Objective: To analyze gene expression patterns in skeletal muscle from burned children. Summary Background Data: Analysis of gene expression patterns in skeletal muscle from burned children can help provide a fundamental understanding of muscle wasting at the molecular level. This study is the first to use such an approach in burned children receiving anabolic treatment. Methods: Children who received 0.1 mg/kg oxandrolone twice a day (n = 7) were compared to placebo (n = 7). Net protein balance was determined before and after treatment with oxandrolone. Total RNA, extracted from muscle biopsies obtained from burned children age 3 to 18 years, was purified, reverse transcribed, and biotinylated cRNA hybridized to the human high-density oligonucleotide array (U95Av2). Western blot analysis verified the mRNA changes at their protein level. Results: DNA microarray analysis showed two genes significantly changed in muscle from burned children receiving placebo, while the expression of 21 genes was altered with oxandrolone. Muscle net protein balance increased with oxandrolone treatment compared to placebo. Conclusions: DNA microarray technology will help identify molecular changes that can serve as targets for new therapies to attenuate muscle wasting in severely burned children and thus improve recovery and early rehabilitation.