ozagrel and Arteriosclerosis

Proliferation of vascular smooth muscle cells stimulated by reactive oxygen species (ROS) may play a pivotal role in the pathogenesis of atherosclerosis. To clarify mechanisms by which ROS promote vascular atherogenesis, effects of fluvastatin, amlodipine, ozagrel (thromboxane synthetase inhibitor), GF109203X (a protein kinase C inhibitor) and Y27632 (a ROCK inhibitor) on the proliferation of guinea-pig basilar artery smooth muscle cells (GBa-SM3) in a 5% FBS culture medium were studied over 3 d in the presence or absence of a free radical scavenger, edaravone. Viability of cells at the end of incubation was measured by the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test. Results demonstrated that fluvastatin and amlodipine by themselves possess antiproliferative effects on the GBa-SM3 cells at 10-100 microM and 0.1-1 microM, respectively. While edaravone possessed no antiproliferative effect by itself at 100 microM, it significantly (p<0.05) augmented the antiproliferative effects of fluvastatin and amlodipine. In addition, ozagrel, GF109203X and Y27632 possessed no appreciable effects on the cell growth by themselves. However, coincubation of edaravone at 100 microM with these agents elicited significant antiproliferative effects for ozagrel, GF109203X and Y27632 at 10-100 microM, 1-10 microM and 0.1-1 microM, respectively. In conclusion, edaravone may have clinically beneficial interactions with fluvastatin, amlodipine and ozagrel regarding the prevention of vascular atherosclerosis. The interactions between edaravone and the inhibitors of protein kinase C and ROCK were suggestive of possible contributions of ROS-triggered intracellular signals associated with these enzymes to vascular atherogenesis, but further studies are required for confirmation.

Topics: Amides; Amlodipine; Animals; Antipyrine; Arteriosclerosis; Basilar Artery; Cell Division; Cell Survival; Cells, Cultured; Drug Synergism; Drug Therapy, Combination; Edaravone; Enzyme Inhibitors; Fatty Acids, Monounsaturated; Fluvastatin; Free Radical Scavengers; Indoles; Maleimides; Methacrylates; Muscle, Smooth, Vascular; Pyridines; Reactive Oxygen Species; Signal Transduction; Tetrazolium Salts; Thiazoles

Atherosclerosis is the main lesion in allografts undergoing chronic rejection. We investigated the effect of OP-2507 (prostaglandin I2 analogue) and OKY-046 (thromboxane A2 synthetase inhibitor) on graft atherosclerosis morphologically and the production of eicosanoids in grafts in a rat aortic allograft model.. Abdominal aortic allografts of Lewis (RT-1(l)) rats were transplanted orthotopically into fully major histocompatibility complex mismatched Wistar King A/Qdj (RT-1(u)) rats that were subcutaneously administered OP-2507 (0.1 mg/kg/d) or OKY-046 (125 mg/kg/d), or both, with an osmotic pump. Four, 8, or 12 weeks later, the grafts were harvested and examined histologically, and the concentration of eicosanoids in the grafts were analyzed.. Lewis aortic allografts in Wistar King A recipients with no treatment displayed atherosclerosis, which involved gradual intimal thickening and medial thinning with continuous inflammation in adventitia. Neither OP-2507 nor OKY-046 treatment affected the intensity of adventitial inflammation. Although inhibition of medial thinning or a decrease in medial nuclear density was not observed, OKY-046 administration alone significantly inhibited an increase in intimal thickness. OP-2507 administration alone significantly inhibited a decrease in medial nuclear density and intimal thickening. Combined treatment with OP-2507 and OKY-046 further decreased the alteration of media and intima. The ratio of thromboxane B2 and 6-keto-prostaglandin F(1alpha) in the grafts was significantly reduced by OKY-046 but not by OP-2507 alone.. We have demonstrated that atherosclerosis in aortic allografts is inhibited by the continuous administration of either OP-2507 or OKY-046, and a combination of both agents strongly increases this inhibitory effect. Amelioration of balance in eicosanoid production in the grafts by the use of thromboxane A2 synthetase inhibitor and the simultaneous usage of stable prostaglandin I2 analogue may be a strategy for preventing atherosclerosis that results from chronic rejection.

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Aorta; Arteriosclerosis; Cell Nucleus; Drug Therapy, Combination; Enzyme Inhibitors; Epoprostenol; Kinetics; Male; Methacrylates; Rats; Rats, Inbred Lew; Rats, Wistar; Superoxides; Thromboxane A2; Thromboxane-A Synthase; Transplantation, Homologous