ono-1301 and Ventricular-Dysfunction--Left

Impairment of cardiac function in cardiomyopathy has been postulated to be related to decreased blood flow and increased collagen synthesis. Administration of growth factors was reported to attenuate left ventricular (LV) remodeling and dysfunction in animal models of dilated cardiomyopathy. We previously reported that ONO-1301, a synthetic prostacyclin agonist with thromboxane-synthase inhibitory activity, promotes production of hepatocyte growth factor and vascular endothelial growth factor from various cell types and ameliorate ischemia-induced LV dysfunction in mice and pigs. We evaluated therapeutic efficacy of ONO-1301 in the Syrian hamster (TO-2), a model of genetically determined dilated cardiomyopathy. Either vehicle or a slow releasing form of ONO-1301 (ONO-1301-PLGA, 10mg/kg/3 weeks) was administered subcutaneously every 3 weeks to TO-2 hamsters from 24 to 32 weeks of age (n=12 for each group). Age-matched F1B hamsters were used as a control. Plasma concentration of HGF was elevated in ONO-1301-PLGA group (p<0.05). Echocardiographic study demonstrated that LV fractional shortening was significantly improved in the ONO-1301-PLGA group (25+/-4%, p<0.01) compared with that in the vehicle group (19+/-2%). Cardiac fibrosis was significantly reduced by ONO-1301-PLGA (p<0.05) as determined by Azan-Mallory staining. Capillary density of left ventricle was markedly reduced in TO-2 hamsters. ONO-1301-PLGA significantly increased capillary density in TO-2 group (p<0.05). ONO-1301 improved LV dysfunction and reduced cardiac fibrosis in the hamster model of dilated cardiomyopathy. ONO-1301 might hold a therapeutic potential in the treatment of dilated cardiomyopathy.

Topics: Animals; Cardiomyopathy, Dilated; Cricetinae; Delayed-Action Preparations; Disease Models, Animal; Drug Carriers; Enzyme Inhibitors; Fibrosis; Lactic Acid; Male; Myocardium; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Pyridines; Thromboxane-A Synthase; Ventricular Dysfunction, Left

It has been shown previously that administration of angiogenic growth factors as genes or proteins can augment collateral growth in ischaemic tissues. In the present study, we have investigated the effect of ONO-1301, a synthetic prostacyclin agonist with thromboxane-synthase-inhibitory activity, on expression of endogenous growth factors and angiogenesis. ONO-1301 induced secretion of HGF (hepatocyte growth factor) and VEGF (vascular endothelial growth factor) from cultured normal human dermal fibroblasts in a dose-dependent manner. Dibutyryl cAMP, an analogue of cAMP, and forskolin, an adenylate cyclase activator, mimicked the effect of ONO-1301. Conversely, Rp-cAMP (adenosine 3',5'-cyclic monophosphorothioate), an inhibitor of cAMP, partially inhibited the effect of ONO-1301, suggesting that cAMP mediated the effect of ONO-1301 in up-regulating the expression of HGF and VEGF, at least in part. ONO-1301 promoted tube-like formation by HUVECs (human umbilical vein endothelial cells) when co-cultured with fibroblasts, and the angiogenic effect of ONO-1301 was abrogated by administration of a neutralizing antibody against HGF or VEGF. To generate a slow-releasing form of ONO-1301, ONO-1301 was mixed with poly(DL-lactic-co-glycolic acid). The slow-releasing form of ONO-1301 was injected directly into the ischaemic myocardium of mice immediately after ligation of the left anterior descending artery. The slow-releasing form of ONO-1301 up-regulated HGF and VEGF expression and increased capillary density in the border zone (342.7+/-29.7 capillaries/mm(2) in controls compared with 557.2+/-26.7 capillaries/mm(2) in treated animals; P<0.01) at 7 days. The slow-releasing form of ONO-1301 ameliorated left ventricular enlargement after 28 days and improved survival rate. In conclusion, our results indicate that ONO-1301 up-regulated endogenous growth factors and promoted angiogenesis in response to acute ischaemia. Therefore ONO-1301 might have a therapeutic potential in treating ischaemic diseases.

Topics: Animals; Dilatation, Pathologic; Dose-Response Relationship, Drug; Enzyme Inhibitors; Epoprostenol; Fibroblasts; Hepatocyte Growth Factor; Humans; Intercellular Signaling Peptides and Proteins; Male; Mice; Mice, Inbred Strains; Myocardial Ischemia; Myocardium; Neovascularization, Pathologic; Pyridines; Thromboxane-A Synthase; Up-Regulation; Vascular Endothelial Growth Factor A; Ventricular Dysfunction, Left