Abstract 17292: The Tissue-Specific Response of Lipoprotein Lipase to Dietary Carbohydrate Predicts Increases in Body Fat Over 4 Years
Background: Enzyme activities of adipose tissue lipoprotein lipase (ATLPL) and skeletal muscle LPL (SMLPL) are influenced in a tissue-specific manner by various factors such as fasting and feeding, macronutrient content of the diet, hormones, and metabolic disease states such as obesity and diabetes. In general, ATLPL predicts fat storage and SMLPL fat oxidation. In this study we evaluated how the short-term effect of dietary macronutrient composition on ATLPL and SMLPL and the responsiveness of the enzyme to meals predicted the long-term (over 4 yrs) stability in body weight and composition in free living adults.
Methods: Thirty-nine healthy men and women (aged 25-36 yr; n=24 normal-weight, n=7 overweight, n=8 obese) each followed a two-week isocaloric high-carbohydrate (HC) and high-fat (HF) diet, using a randomized crossover design and washout period between diets. On day 15 of each diet, biopsies were performed in the fasted state and 6 hrs after a HC and HF meal. Body weight and composition were measured annually over 4 yrs. The outcomes for body weight, fat mass and % body fat were assessed using a linear 2-stage mixed model, with adjustment for sex and baseline BMI.
Results: The mean (±SEM) increase in body weight and fat mass over 4 yrs were 0.29 ± 0.15 kg/yr (p=0.063) and 0.31 ± 0.15 kg/yr (p=0.051), respectively. The most consistent predictors of future body weight and fat changes were the ATLPL and SMLPL responses (0-6 hrs) to a HC diet/meal. For the HC diet and meal, the subjects who had an increase in ATLPL activity/cell on day 15 gained more % body fat over 4 yrs (p=0.006) whereas subjects who had a decrease in SMLPL activity/g also had an increase in fat mass (P=0.021; crude model). A trend was also observed between fasting SMLPL and changes in % body fat (r=-0.034 ± 0.034; p=0.056). No significant relationships were observed between fasting ATLPL and SMLPL or enzyme responses to meals and any of the outcomes following the HF diet. There were also no differences between normal weight, overweight and obese groups in the relationship between ATLPL and/or SMLPL and changes in body composition over 4 yrs.
Conclusions: In free-living adults the variability in tissue-specific LPL responsiveness to a HC diet/meal predicts changes in body composition over 4 yrs.
- © 2010 by American Heart Association, Inc.