beraprost and Atherosclerosis

Beraprost sodium (BPS) is a stable orally active prostacyclin analogue with vasodilatory and anti-platelet effects, and has been widely used as therapeutics for pulmonary artery hypertension and chronic arterial obstruction. In order to elucidate its effects on endothelium, we first examined the short-term effects of BPS on nitric oxide (NO) production and endothelial NO synthase (eNOS) activation using bovine aortic endothelial cells. Short-term treatment of BPS induced NO production as well as eNOS phosphorylation at Ser-1179 mediated via cAMP/protein kinase A (PKA) pathway. The effects of BPS on capillary-like tube formation were next determined using human umbilical vein ECs (HUVECs)/normal human dermal fibroblasts co-culture system. BPS was observed to induce capillary-like tube formation mediated via cAMP/PKA pathway, but not via NO generation. Finally, we performed DNA microarray analyses using RNA extracted from BPS treated HUVECs. Interestingly, BPS up-regulated several genes involved in angiogenesis, anti-atherosclerosis, and endothelial function, while down-regulated several genes involved in atherosclerosis. Our data therefore indicate that BPS may be useful not only for patients with pulmonary artery hypertension and chronic arterial obstruction, but also for general atherosclerotic patients complicated with endothelial dysfunction. Further studies are needed to clarify molecular mechanisms of these BPS effects including the involvement of peroxisome proliferator-activated receptor-delta.

Topics: Animals; Arterial Occlusive Diseases; Atherosclerosis; Cardiovascular Diseases; Endothelium, Vascular; Epoprostenol; Gene Expression Regulation; Humans; Hypertension, Pulmonary; Neovascularization, Physiologic; Nitric Oxide; Nitric Oxide Synthase Type III; Platelet Aggregation Inhibitors; Signal Transduction; Vasodilator Agents

Diabetes mellitus is an important risk factor for cardiovascular morbidity and mortality. The metabolic abnormalities caused by diabetes mellitus induce vascular endothelial dysfunction that predisposes patients with diabetes mellitus to atherosclerosis. Two mega clinical trials showed that intensive glycemic control does not have favorable effects on reducing macrovascular events although it demonstrated significant reductions in microvascular complications. It is becoming worthwhile to clarify the beneficial effects of tight controls on blood pressure, serum lipids, and postprandial hyperglycemia to prevent atherosclerosis in patients with type 2 diabetes mellitus. Here, we focus on vascular endothelium as a target of the prostaglandin I2 analog beraprost sodium and the peroxisome proliferators-activated receptor alpha activator fenofibrate for the prevention and treatment of atherosclerosis in patients with type 2 diabetes mellitus. Beraprost sodium lowered circulating vascular cell adhesion molecule- 1 (VCAM-1) concentration and prevented the progression of carotid atherosclerosis in type 2 diabetic patients, probably through inhibiting VCAM-1 expression in vascular endothelium. Fenofibrate up-regulated endothelial nitric oxide synthase expression, which may explain its effects to improve endothelium-dependent vasodilatation and to prevent the progression of coronary atherosclerosis. The approaches to target the molecules expressed in vascular endothelium will become important for preventing the atherosclerosis in type 2 diabetes mellitus.

Topics: Antihypertensive Agents; Atherosclerosis; Blood Glucose; Blood Pressure; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Drug Therapy, Combination; Endothelium, Vascular; Epoprostenol; Fenofibrate; Humans; Hypoglycemic Agents; Hypolipidemic Agents; Lipid Metabolism; Nitric Oxide Synthase Type III; Vascular Cell Adhesion Molecule-1; Vasodilation; Vasodilator Agents