Abstract 16791: Oral Administration of Synthetic Prostacyclin Agonist Ono-1301 Prevents Deterioration of Cardiac Performance by Preserving Cardiac Structural Proteins in the Delta-sarcoglycan-deficient Hamster: Promising Treatment for Patients With DCM

Abstract

Background: Although drugs such as beta blockers are reported to be effective for dilated cardiomyopathy (DCM), they are only effective in selected patients, and new therapeutics based on different mechanisms are still needed. We hypothesized that synthetic prostacyclin agonist (ONO-1301) would preserve the structural proteins in distressed cardiomyocytes, thus attenuating the deterioration of cardiac performance in the delta sarcoglycan-deficient hamster. Methods and Results: In an in vitro study, ONO-1301 was added to the culture medium of non-myocyte cells and the expression of several cytokines including VEGF was examined by ELISA. For the in vivo study, ONO-1301 (A: 3, n=5, B: 1, n=6, C: 0.3, n=7, D: 0.1 mg/kg/dose, n=7) was orally administered to delta-sarcoglycan-deficient hamsters every day from 8 to 20 weeks after birth. The control group (n=6) was untreated. Functional performance was evaluated by US before, 2, 4, 6, and 8 weeks after administration of ONO-1301. A histological analysis focusing on basement-membrane structural proteins, such as α-sarcoglycan, β-sarcoglycan, and α-dystroglycan, fibrosis, and hypertrophy was performed. In vitro, ONO-1301 enhanced the cytokine expressions dose dependently. In vivo, systolic function (EF) was gradually increased in the ONO-1301-treated groups, while it showed significant deterioration in the control group (45.7±2.9, 42.0±2.6, 32.3±1.0, 30.3±2.5, 26.3±2.7%, in groups A, B, C, D, and control, respectively, P<0.05). ONO-1301 also significantly attenuated the LV dilatation in a dose-dependent manner. Immunostaining revealed that all the cardiac structural proteins were preserved in the basement membrane of cardiomyocytes in the 3.0 mg/kg ONO-1301 treatment group, while they disappeared in the control. The % fibrosis and cell hypertrophy were significantly attenuated in the ONO-1301-treated group compared with the control. Conclusions: Oral administration of synthetic prostacyclin agonists, which can enhance cytokine expressions in non-myocyte cells, may preserve cardiac structural proteins in the delta sarcoglycan-deficient hamster, to maintain cardiac performance. This promising drug may inhibit the progression of the disease pathology in DCM, prolonging their life.