Yoshiki Sakai

A Novel Prostacyclin Agonist Protects against Airway Hyperresponsiveness and Remodeling in Mice

Airway remodeling in bronchial asthma results from chronic, persistent airway inflammation. The effects of the reversal of airway remodeling by drug interventions remain to be elucidated. We investigated the effects of ONO-1301, a novel prostacyclin agonist with thromboxane inhibitory activity, on the prevention and reversibility of airway remodeling in an experimental chronic asthma model. Mice sensitized and challenged to ovalbumin (OVA) three times a week for 5 consecutive weeks were administered ONO-1301 or vehicle twice a day from the fourth week of OVA challenges. Twenty-four hours after the final OVA challenge, airway hyperresponsiveness (AHR) was assessed, and bronchoalveolar lavage was performed. Lung specimens were excised for staining to detect goblet-cell metaplasia, airway smooth muscle, and submucosal fibrosis. Mice administered ONO-1301 showed limited increases in AHR compared with mice administered the vehicle. The histological findings of airway remodeling were improved in ONO-1301-treated mice compared with vehicle-treated mice. Presumably, these therapeutic effects of ONO-1301 are attributable to the up-regulation of production of hepatocyte growth factor (HGF) in lung tissue, because the neutralization of HGF by antibodies prevented the effects of ONO-1301 on AHR and airway remodeling. Mice administered ONO-1301 showed similar levels of AHR and airway remodeling as mice administered montelukast, a cysteinyl-leukotriene-1 receptor antagonist, and lower levels were observed in mice administered dexamethasone. These data suggest that ONO-1301 exerts the effect of reversing airway remodeling, at least in part through an elevation of HGF in the lungs, and may be effective as an anti-remodeling drug in the treatment of asthma.

Synthetic prostacyclin agonist, ONO1301, enhances endogenous myocardial repair in a hamster model of dilated cardiomyopathy: A promising regenerative therapy for the failing heart

OBJECTIVESnRemodeling of the left ventricle (LV) in idiopathic dilated cardiomyopathy (IDCM) is known to be associated with multiple pathologic changes that endogenous factors, such as hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF), protect against. Although a clinically relevant delivery method of these factors has not been established, ONO1301, a synthetic prostacyclin agonist, has been shown to upregulate multiple cardioprotective factors, including HGF and VEGF, inxa0vivo. We thus hypothesized that ONO1301 may reverse LV remodeling in the DCM heart.nnnMETHODSnONO1301 dose-dependently added to the normal human dermal fibroblasts and human coronary artery smooth muscle cells inxa0vitro, to measure the expression of HGF, VEGF, stromal cell-derived factor (SDF)-1, and granulocyte-colony stimulating factor (G-CSF), assessed by real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay. δ-Sarcoglycan-deficient J2N-k hamsters, which is an established DCM model, were treated by epicardial implantation of an atelocollagen sheet with or without ONO1301 immersion or sham operation.nnnRESULTSnONO1301 dose-dependently upregulated expression of these 4 factors inxa0vitro. ONO1301 treatment, which induced dominant elevation of ONO1301 levels for 2 weeks, significantly preserved cardiac performance and prolonged survival compared with the other groups. This treatment significantly upregulated expressions of cardioprotective factors and was associated with increased capillaries, attenuated fibrosis, and upregulation of α-sarcoglycan in the DCM heart.nnnCONCLUSIONSnONO1301 atelocollagen-sheet implantation reorganized cytoskeletal proteins, such as α-sarcoglycan, increased capillaries, reduced fibrosis, and was associated with upregulated expression of multiple cardioprotective factors, leading to preservation of cardiac performance and prolongation of survival in the δ-sarcoglycan-deficient DCM hamster.

Impact of cardiac support device combined with slow-release prostacyclin agonist in a canine ischemic cardiomyopathy model.

BACKGROUNDnThe cardiac support device supports the heart and mechanically reduces left ventricular (LV) diastolic wall stress. Although it has been shown to halt LV remodeling in dilated cardiomyopathy, its therapeutic efficacy is limited by its lack of biological effects. In contrast, the slow-release synthetic prostacyclin agonist ONO-1301 enhances reversal of LV remodeling through biological mechanisms such as angiogenesis and attenuation of fibrosis. We therefore hypothesized that ONO-1301 plus a cardiac support device might be beneficial for the treatment of ischemic cardiomyopathy.nnnMETHODSnTwenty-four dogs with induced anterior wall infarction were assigned randomly to 1 of 4 groups at 1xa0week postinfarction as follows: cardiac support device alone, cardiac support device plus ONO-1301 (hybrid therapy), ONO-1301 alone, or sham control.nnnRESULTSnAt 8 weeks post-infarction, LV wall stress was reduced significantly in the hybrid therapy group compared with the other groups. Myocardial blood flow, measured by positron emission tomography, and vascular density were significantly higher in the hybrid therapy group compared with the cardiac support device alone and sham groups. The hybrid therapy group also showed the least interstitial fibrosis, the greatest recovery of LV systolic and diastolic functions, assessed by multidetector computed tomography and cardiac catheterization, and the lowest plasma N-terminal pro-B-type natriuretic peptide levels (Pxa0<xa0.05).nnnCONCLUSIONSnThe combination of a cardiac support device and the prostacyclin agonist ONO-1301 elicited a greater reversal of LV remodeling than either treatment alone, suggesting the potential of this hybrid therapy for the clinical treatment of ischemia-induced heart failure.

Enhanced Pulmonary Vascular and Alveolar Development via Prenatal Administration of a Slow-Release Synthetic Prostacyclin Agonist in Rat Fetal Lung Hypoplasia.

Lung hypoplasia and pulmonary hypertension are the major causes of mortality in neonates with congenital diaphragmatic hernia (CDH). Although the prostaglandin pathway plays a pivotal role in lung development, the reported efficacy of postnatal prostaglandin agonist treatment is suboptimal. We hypothesized that prenatal treatment with ONO-1301SR, a slow-release form of a novel synthetic prostacyclin agonist with thromboxane inhibitory activity, might enhance the development of lungs exhibiting hypoplasia in the fetal period. On embryonic day (E) 9.5, nitrofen was given to pregnant Sprague-Dawley rats to establish a CDH-related lung hypoplasia model, whereas normal rats received the vehicle only. The same day, either ONO-1301SR or a placebo was also randomly administered. On E21.5, the fetuses of the normal group and those exhibiting CDH were analyzed. Prenatal ONO-1301SR administration had no influence on the incidence of nitrofen-induced CDH. The lung-to-body weight ratio in the CDH+ONO group was greater than that in the CDH group. Histologically, the medial wall in the CDH+ONO group was two-thirds thinner than that in the CDH group. In addition, the number of Ttf-1-positive cells and the capillary density were ≥1.5 times greater in the CDH+ONO group than in the CDH group, and this increase was associated with higher expression of vascular endothelial growth factor and stromal cell-derived factor in the CDH+ONO group, suggesting enhanced development of the alveolar and capillary networks. Thus, prenatal ONO-1301SR was protective against the progression of lung hypoplasia associated with CDH in a nitrofen-induced rat model, indicating the potential of this treatment for pathologies exhibiting lung hypoplasia.

Sustained-Release Delivery of Prostacyclin Analogue Enhances Bone Marrow-Cell Recruitment and Yields Functional Benefits for Acute Myocardial Infarction in Mice

Background A prostacyclin analogue, ONO-1301, is reported to upregulate beneficial proteins, including stromal cell derived factor-1 (SDF-1). We hypothesized that the sustained-release delivery of ONO-1301 would enhance SDF-1 expression in the acute myocardial infarction (MI) heart and induce bone marrow cells (BMCs) to home to the myocardium, leading to improved cardiac function in mice. Methods and Results ONO-1301 significantly upregulated SDF-1 secretion by fibroblasts. BMC migration was greater to ONO-1301-stimulated than unstimulated conditioned medium. This increase was diminished by treating the BMCs with a CXCR4-neutralizing antibody or CXCR4 antagonist (AMD3100). Atelocollagen sheets containing a sustained-release form of ONO-1301 (nu200a=u200a33) or ONO-1301-free vehicle (nu200a=u200a48) were implanted on the left ventricular (LV) anterior wall immediately after permanent left-anterior descending artery occlusion in C57BL6/N mice (male, 8-weeks-old). The SDF-1 expression in the infarct border zone was significantly elevated for 1 month in the ONO-1301-treated group. BMC accumulation in the infarcted hearts, detected by in vivo imaging after intravenous injection of labeled BMCs, was enhanced in the ONO-1301-treated hearts. This increase was inhibited by AMD3100. The accumulated BMCs differentiated into capillary structures. The survival rates and cardiac function were significantly improved in the ONO-1301-treated group (fractional area change 23±1%; nu200a=u200a22) compared to the vehicle group (19±1%; nu200a=u200a20; Pu200a=u200a0.004). LV anterior wall thinning, expansion of infarction, and fibrosis were lower in the ONO-1301-treated group. Conclusions Sustained-release delivery of ONO-1301 promoted BMC recruitment to the acute MI heart via SDF-1/CXCR4 signaling and restored cardiac performance, suggesting a novel mechanism for ONO-1301-mediated acute-MI heart repair.

A slow-releasing form of prostacyclin agonist (ONO1301SR) enhances endogenous secretion of multiple cardiotherapeutic cytokines and improves cardiac function in a rapid-pacing–induced model of canine heart failure

OBJECTIVESnCardiac functional deterioration in dilated cardiomyopathy (DCM) is known to be reversed by intramyocardial up-regulation of multiple cardioprotective factors, whereas a prostacyclin analog, ONO1301, has been shown to paracrinally activate interstitial cells to release a variety of protective factors. We here hypothesized that intramyocardial delivery of a slow-releasing form of ONO1301 (ONO1301SR) might activate regional myocardium to up-regulate cardiotherapeutic factors, leading to regional and global functional recovery in DCM.nnnMETHODS AND RESULTSnONO1301 elevated messenger RNA and protein level of hepatocyte growth factor, vascular endothelial growth factor, and stromal-derived factor-1 of normal human dermal fibroblasts in a dose-dependent manner in vitro. Intramyocardial delivery of ONO1301SR, which is ONO1301 mixed with polylactic and glycolic acid polymer (PLGA), but not that of PLGA only, yielded significant global functional recovery in a canine rapid pacing-induced DCM model, assessed by echocardiography and cardiac catheterization (n = 5 each). Importantly, speckle-tracking echocardiography unveiled significant regional functional recovery in the ONO1301-delivered territory, consistent to significantly increased vascular density, reduced interstitial collagen accumulation, attenuated myocyte hypertrophy, and reversed mitochondrial structure in the corresponding area.nnnCONCLUSIONSnIntramyocardial delivery of ONO1301SR, which is a PLGA-coated slow-releasing form of ONO1301, up-regulated multiple cardiotherapeutic factors in the injected territory, leading to region-specific reverse left ventricular remodeling and consequently a global functional recovery in a rapid-pacing-induced canine DCM model, warranting a further preclinical study to optimize this novel drug-delivery system to treat DCM.

A prostacyclin agonist and an omental flap increased myocardial blood flow in a porcine chronic ischemia model

Objective: We hypothesized that therapeutic efficacy may be augmented by a combination of placing a sheet immersed in ONO‐1301SR, a slow‐release synthetic prostacyclin agonist‐inducing multiproangiogenic cytokines, over the left ventricle and a pedicled omental flap in a chronic myocardial infarct heart. Methods: A minipig chronic myocardial infarction was generated by placing an ameroid constrictor ring around the left anterior descending artery for 4 weeks. The minipigs were then assigned into 4 groups of 6 each: sham, omental flap only, ONO‐1301SR only, and ONO‐1301SR combined with an omental flap (combined). Four weeks after treatment, therapeutic efficacy was evaluated histologically and via several modalities used in the clinical setting. Results: In an angiogram and pressure wire study, the combined group induced development of collateral arteries to decrease the resistance and increase the flow reserve of microvasculature in the left circumflex territory. In a 13N‐ammonia positron emission tomography study, the combined group displayed a prominent increase in myocardial blood flow and myocardial flow reserve in the left circumflex territory, particularly at the infarct‐border region. Consequently, the combined group showed greater regional cardiac function in the left circumflex territory particularly at the infarct‐border region, contributing to a greater global ejection fraction with a smaller left ventricular endosystolic volume. Pathologically, attenuated fibrosis, nonswollen myocytes, and upgraded capillary density and proangiogenic cytokines were prominent in the combined group. Conclusions: ONO‐1301SR combined with a pedicled omental flap synergistically promoted myocardial angiogenesis, leading to function recovery in a porcine chronic myocardial infarction model.

172 A Slow-Releasing Synthetic Prostacyclin Agonist “Ono 1301-sr†Combined with Omental Flap Increases Myocardial Blood Flow and Reduces Microvascular Resistance, Associated with Functional Recovery, in a Porcine Chronic Myocardial Infarction Model

Introduction Coronary microvascular dysfunction (MVD) has been shown to be the major cause of persistent myocardial ischaemia and progressive left ventricular (LV) remodelling in the chronic myocardial infarction (MI) heart. ONO-1301SR is a slow-releasing synthetic prostacyclin agonist, being developed to induce angiogenesis by upregulating a variety of proangiogenic cytokines in the targeted region. In addition, pedicle omental flap covering over the LV surface reportedly yields proangiogenic effects on chronic MI heart. We herein hypothesised pedicle omental flap covering, combined with ONO-1301SR placement. over the LV surface may be effective on the MVD and related functional deterioration in a chronic MI heart. To test this hypothesis, clinically latest imaging studies were applied in a porcine chronic MI model. Methods A mini-pig chronic MI model was generated by placing an ameroid constrictor around the left anterior descending artery for 4 weeks. The mini-pigs were then randomly assigned into the following 4 groups; sham group, omental flap alone (OM group), ONO-1301SR alone (ONO group), ONO-1301SR plus omental flap (ONO+OM group, n = 6 each). Results At 4 weeks after the treatment, 13N-ammonia PET study showed that the ONO+OM group, but not the other groups, displayed a significantly increase in myocardial blood flow (189 ± 89% increase, P < 0.05) and coronary flow reserve (179 ± 121% increase, P < 0.05) under the stress compared to those under the rest. This trend was predominated in the left circumflex territory. In addition, coronary angiogram and pressure-temperature sensor wire study showed that the ONO+OM and the ONO groups, but not the OM group, showed a significantly greater number of collateral arteries and smaller indexed of microvascular resistance, in particular, in the left circumflex territory, compared to the sham group. Moreover, echocardiographical EF was significantly greater in the ONO+OM group (50 ± 7%) and the ONO group (48 ± 3%), compared to the OM group (41 ± 3%) and the sham group (38 ± 5%) at 4 weeks. Furthermore, histological density of CD31-positive capillaries and CD31SMA-double positive arterioles were significantly greater in the ONO+OM group than the sham group or the OM group, in association with a significantly smaller myocyte size and interstitial fibrous area in the ONO+OM and the ONO group compared to those in the other groups. However, expression of proangiogenic cytokines, such as vascular endothelial growth factor, hepatocyte growth factor or stem cell-derived factor-1, were not significantly different among the groups, indicating that angiogenic process might have been completed at the 4 weeks after the treatment. Conclusions ONO-1301SR combined with omental flap therapy promoted myocardial angiogenesis with collateral artery growth, leading to recovery of the cardiac function in a porcine ICM model. This combined therapy may be useful in regenerating myocardial microvasculature.

A sustained-release drug-delivery system of synthetic prostacyclin agonist, ONO-1301SR: a new reagent to enhance cardiac tissue salvage and/or regeneration in the damaged heart

Cardiac failure is a major cause of mortality and morbidity worldwide, since the standard treatment for cardiac failure in the clinical practice is chiefly to focus on removal of insults against the heart or minimisation of additional factors to exacerbate cardiac failure, but not on regeneration of the damaged cardiac tissue. A synthetic prostacyclin agonist, ONO-1301, has been developed as a long-acting drug for acute and chronic pathologies related to regional ischaemia, inflammation and/or interstitial fibrosis by pre-clinical studies. In addition, poly-lactic co-glycolic acid-polymerised form of ONO-1301, ONO-1301SR, was generated to achieve a further sustained release of this drug into the targeted region. This unique reagent has been shown to act on fibroblasts, vascular smooth muscle cells and endothelial cells in the tissue via the prostaglandin IP receptor to exert paracrinal release of multiple protective factors, such as hepatocyte growth factor, vascular endothelial growth factor or stromal cell-derived factor-1, into the adjacent damaged tissue, which is salvaged and/or regenerated as a result. Our laboratory developed a new surgical approach to treat acute and chronic cardiac failure using a variety of animal models, in which ONO-1301SR is directly placed over the cardiac surface to maximise the therapeutic effects and minimise the systemic complications. This review summarises basic and pre-clinical information of ONO-1301 and ONO-1301SR as a new reagent to enhance tissue salvage and/or regeneration, with a particular focus on the therapeutic effects on acute and chronic cardiac failure and underlying mechanisms, to explore a potential in launching the clinical study.