High preβ1-HDL levels in hypercholesterolemia are maintained by probucol but reduced by a low-cholesterol diet Original Research Article

Previous study has shown that preβ1-HDL levels increase in hypercholesterolemia, or high cholesteryl ester transfer protein (CETP) activity. To determine how preβ1-HDL levels change after treatment with probucol or by following a low-cholesterol diet, we randomly assigned 24 hypercholesterolemic patients to either the probucol (P), or low-cholesterol diet group (D), and measured preβ1-HDL levels before and after treatments using native two-dimensional gel electrophoresis. We also examined 12 subjects with normolipidemia (N). At baseline, preβ1-HDL levels were higher in P (P<0.05) and D (P<0.05) than in N (9.2±4.3, 10.4±5.5, and 5.9±2.3 mg/dl apo A-I). After a 4-week treatment, preβ1-HDL levels were still high in P (10.5±4.2 mg/dl apo A-I, N.S.), but reduced in D (7.7±3.0 mg/dl apo A-I, P<0.001). Δpreβ1-HDL (Y) was positively correlated with ΔCETP mass (X) in P (y=7.83x−1.93; r=0.584, P<0.05). In summary, high preβ1-HDL levels in hypercholesterolemia are maintained by probucol but reduced by a low-cholesterol diet. These findings suggest that preβ1-HDL levels may be regulated by cholesterol and CETP levels.