Cilostazol, a potent phosphodiesterase type III inhibitor, selectively increases antiatherogenic high-density lipoprotein subclass LpA-I and improves postprandial lipemia in patients with type 2 diabetes mellitus

Low levels of high-density lipoproteins cholesterol (HDL-C) as well as impaired postprandial lipemia are known to be associated with the increased risk for coronary artery disease (CAD) in patients with type 2 diabetes mellitus (type 2 DM). HDL are heterogeneous in size and apolipoprotein composition. Recent evidence indicates that among the 2 major HDL subclasses, those without apolipoprotein A-II (LpA-I) are more antiatherogenic compared with those with apoA-II (LpA-I:A-II). Cilostazol, a novel selective phosphodiesterase type III inhibitor, has been shown to inhibit platelet activation and is also a potent vasodilator. Additionally, cilostazol has been shown to modulate lipoprotein profiles by raising HDL-C and lowering plasma triglyceride (TG) levels. The present study investigated the effect of cilostazol on HDL composition (LpA-I and LpA-I:A-II levels) and postprandial lipemia in patients with type 2 DM. Seventeen patients were given cilostazol 200 mg twice daily for 12 weeks. At weeks 0 and 12, fat tolerance tests (30 g/m(2)) were performed to assess postprandial lipemia. Plasma TG and remnant-like lipoprotein particles cholesterol (RLP-C) were significantly decreased by 17% and 26%, respectively (P <.05), and HDL-C was significantly increased by 14% (P <.01). LpA-I was significantly increased by 23% (P <.01) from the mean value of 45 mg/dL to 55 mg/dL. In contrast, LpA-I:A-II remained unchanged, resulting in significantly increased %LpA-I (apoA-I on LpA-I/total apoA-I x 100) from 35% to 40% (P <.01). Areas under the curve for TG and RLP-C after the fat meal were both nonsignificantly decreased by 17%. Patients with higher plasma TG levels had a greater benefit from the treatment with cilostazol as revealed by fasting TG levels and fat tolerance tests. HDL-C responses to cilostazol were independent of baseline plasma TG levels or percentage changes in TG, indicating that the underlying mechanisms for raising HDL and reducing TG levels are distinct. In conclusion, cilostazol selectively increased LpA-I, thus favorably altering HDL towards a more antiatherogenic composition. This finding, together with the improved postprandial lipemia, indicates that cilostazol has a potent antiatherogenic function by modulating HDL and remnant metabolism in patients with type 2 DM.