Medicine & Science in Sports & Exercise:
G-14 Free Communication/Poster - Children and Adolescents 2: MAY 31, 2008 7:30 AM - 11:00 AM ROOM: Hall B
Roberts, Christian K. FACSM; Eliseo, Anna Jane; Barnard, R. James FACSM
Univeristy of California, Los Angeles, Los Angeles, CA.
(No relationships reported)
PURPOSE: Autopsy studies indicate that atherosclerosis development often begins in the first decade of life and is exacerbated by obesity. The present study was designed to examine the effects of lifestyle modification on adipokines in overweight children without documented atherosclerosis.
METHODS: Twenty overweight children (10 boys, 10 girls, ages 8-17 yr, mean 13±0.5 yr, with a BMI of 30.9±2.0, were placed on a high-fiber, low-fat diet in the Pritikin Longevity Center 2-week residential program where food was provided ad libitum and daily exercise (2-2.5 hr) was performed. In each subject, fasting serum samples were acquired pre-and post-intervention for determination of serum insulin, adiponectin, leptin, TNFα, IL-6, and soluble IL-6 receptor (sIL-6R) by enzymelinked immunosorbent assays (ELISA). Human subcutaneous adipocyte cultures were incubated with pre-and post-intervention serum for 3 days and secreted levels of IL-6, MCP-1, adiponectin and leptin were determined (N=5). Additionally, fasting lipid profiles and glucose levels were determined using automated enzymatic procedures and body composition was determined by dual-energy X-ray absorptiometry.
RESULTS: After the 2-week program, subjects lost weight (80.5±7.1 vs. 83.8±7.4 kg) but remained overweight/obese (BMI: 29.7±1.9 vs. 30.9±2.0, BMI percentile: 91.5±3.8% vs. 92.3±4.0%, body fat: 33.7±1.8 vs. 34.9±1.8%, all p<0.01). Serum insulin (16.9±1.6 vs. 24.8±3.0 ng/mL), leptin (11.9±4.1 vs. 27.0±8.0 ng/mL), TNFα (1.3±0.2 vs. 2.3±0.3 pg/mL), and IL-6 (1.1±0.1 vs. 2.4±0.2 pg/mL) all decreased (p<0.01) while adiponectin (7.8±0.8 vs. 5.7±0.4 ìg/mL, p<0.01) and sIL-6R (74.0±12.7 vs. 52.2±7.8 pg/mL, p=0.03) increased. Post-intervention serum-stimulated adipocyte cultures (n=5) revealed reduced secretion of IL-6 (1.1±0.4 vs. 2.5±0.2 ng, p=0.06), but not MCP-1 (7.1±0.9 vs. 8.5±0.9, p=0.19). Levels of adiponectin and leptin were not detectable in supernatants.
CONCLUSION: These results indicate significant modification of serum adipokine levels and serum-stimulated adipocyte adipokine production with short-term, rigorous lifestyle modification, even in the face of remaining obese.