Hemobiological properties of gliclazide

Abstract

Non-insulin-dependent diabetes mellitus (NIDDM) is associated with an increased risk of macro- and microvascular degenerative complications. Gliclazide is a second generation sulfonylurea that is widely used in the treatment of type II diabetes mellitus. Its hypoglycemic activity is well documented. In addition to its metabolic effects, gliclazide has beneficial effects on the hemobiological abnormalities of NIDDM. These effects are mediated by the azabicyclo-octyl ring grafted on to its aulfonylurea core. Numerous studies have demonstrated that gliclazide reduces platelet hyperadhesion and platelet hyperaggregability. These actions have been extensively confirmed in diabetic patients over periods of up to 3 years. With regard to platelet functions, several groups have demonstrated a significant reduction in serum and intraplatelet β thromboglobulin and thromboxane B 2. In animal models, in-vitro and in-vivo gliclazide stimulates endothelial prostacyclin synthesis. The beneficial effects of the compound on thromboxane/prostacyclin balance have been recently confirmed in type II diabetic patients after a 3-month treatment period. Concerning fibrinolysis, gliclazide restores low plasminogen activity to normal in NIDDM patients previously treated with first-generation sulfonyl-ureas. Gliclazide increases fibrinolytic potential by increasing endothelial cell tissue plasminogen activator and pre-kallikrein activity. More recent studies suggest that gliclazide may have effects on fibrin network structure, rendering the fibrin more amenable to fibrinolysis. Finally, it has been shown that gliclazide has a potent free-radical-scavenging activity in vitro. This property has been recently confirmed in vivo in type II diabetic patients and may suggest that platelet reactivity and oxidative stress are related in these patients. It is worth noting that the hemobiological properties of gliclazide are largely independent of its hypoglycemic activity. In addition, these properties are not shared with other first or second generation sulfonylureas.