C-27 Free Communication/Poster - Fat Metabolism: MAY 29, 2008 7:30 AM - 12:30 PM ROOM: Hall B
PURPOSE: Abnormal cholesterol metabolism, including low intestinal cholesterol absorption and elevated cholesterol synthesis, is prevalent in individuals with diabetes, hyperlipidemia, obesity, and the metabolic syndrome. Diet-induced weight loss improves cholesterol absorption in these populations; the purpose of this study is to investigate if endurance exercise training also improves cholesterol homeostasis.
METHODS: We measured circulating levels of campesterol, sitosterol, lathosterol, and cholesterol by GC/mass spectrometry from 65 sedentary subjects (34 women, 31 men, average age = 59) with at least 1 metabolic syndrome risk factor before and after 6 months of endurance exercise training. Campesterol and sitosterol are plant sterols that correlate with intestinal cholesterol absorption, while lathosterol, a precursor in the cholesterol synthetic pathway, is a marker of whole body cholesterol synthesis. We also measured plasma glucose, insulin, VO2max, and body composition by DEXA and CT scanning before and after the intervention.
RESULTS: Following the intervention, plasma levels of total plant sterols (campesterol + sitosterol) were increased by 10% (p < 0.05), but there was no change in plasma lathosterol. In addition, total and LDL-cholesterol were both reduced by ~6 mg/dL (p < 0.05 for each), while HDL-C levels increased by 3.3mg/dL (p < 0.05). Furthermore, the change in total plant sterols (campesterol + sitosterol) was positively correlated with the change in VO2max (r = 0.310, p = 0.004), independent of other metabolic syndrome risk factors.
CONCLUSIONS: These data indicate that exercise training reduces plasma cholesterol despite increasing cholesterol absorption in middle-to older-aged subjects with risk factors for metabolic syndrome.