In vivo evidence for the role of lipoprotein lipase activity in the regulation of apolipoprotein AI metabolism: a kinetic study in control subjects and patients with type II diabetes mellitus.

The aim of this study was to delineate the role of lipoprotein lipase(LPL) activity in the kinetic alterations of high density lipoprotein (HDL) metabolism in patients with type II diabetes mellitus compared with controls. The kinetics of HDL were studied by endogenous labeling of HDL apolipoprotein AI(HDL-apo AI) using a primed infusion of D3-leucine. The HDL-apo AI fractional catabolic rate (FCR) was significantly increased (0.32 ± 0.07 vs. 0.23 ± 0.05 pool/day; P < 0.01), and HDL composition was changed [HDL cholesterol, 0.77 ± 0.16 vs. 1.19 ± 0.37 mmol/L (P < 0.05); HDL triglycerides, 0.19 ± 0.12 vs. 0.10 ± 0.03 mmol/L (P < 0.05)] in diabetic patients compared with healthy subjects. HDL-apo AI FCR was correlated to plasma and HDL triglyceride concentrations (r = 0.82; P < 0.05 and r = 0.80; P< 0.05, respectively) and to homeostasis model assessment (r = 0.78; P < 0.05). Postheparin plasma LPL activity was decreased in type II diabetes (6.8 ± 2.8 vs. 18.1 ± 5.2 μmol/mL postheparin plasma·h; P < 0.005...