Abstract 16343: Sarpogrelate, a Selective Serotonin 2a Receptor Antagonist, Suppresses Pressure Overlaod-induced Cardiac Hypertrophy and Systolic Dysfunction Through Inhibiting Erk1/2/gata4 Pathway

Abstract

Introduction: Serotonin (5-HT), a neurohormone involved in a wide range of physiological functions, has generated much interest in recent years regarding its potential role in cardiac function. It is reported that sarpogrelate, a selective 5-HT2A receptor antagonist, possesses cardioprotective effect against myocardial infarction, however, the precise molecular mechanism of the effect is still unclear. In this study, we examined the effect of sarpogrelate on pressure overload-induced development of heart failure, another heart failure model. Methods: First, primary cultured cardiomyocytes were treated with 1 μM sarpogrelate and then stimulated with various hypertrophic stimuli. Cardiomyocytes were stained with anti-actinin antibody and the surface area of the cells were measured. The phosphorylation levels of ERK1/2 and GATA4 were assessed by western blotting. Next, C57BL/6j male mice were subjected to a transverse aortic constriction (TAC) and sham operation. One day after the operation, the mice were randomly divided into 3 groups: sarpogrelate at 1 mg/kg or 5 mg/kg, and vehicle as a control. Daily oral administration was repeated for 8 weeks. Results: Sarpogrelate significantly suppressed an increase in the surface area of cardiomyocytes induced not only by 5-HT, but also by phenylephrine, angiotensin II and ET-1. Sarpogrelate suppressed phenylephrine-induced phosphorylation of ERK1/2 and GATA4. In a mice model of heart failure, echocardiographic analysis showed that 5 mg/kg sarpogrelate significantly prevented a TAC-induced increase in posterior left ventricular wall thickness and a decrease in fractional shortening at 8 weeks after the operation. One mg/kg sarpogrelate also suppressed TAC-induced increase in HW/BW ratio, myocardial cell diameter and the mRNA levels of ANF and BNP. Moreover, 1 mg/kg sarpogrelate significantly suppressed TAC-induced phosphorylation of ERK1/2. Conclusions: These results indicate that sarpogrelate significantly suppresses cardiomyocyte hypertrophy and the development of heart failure via at least, in part, by inhibition of ERK1/2/GATA4 pathway. These findings suggest that sarpogrelate may be an effective agent for heart failure therapy.