Here we show that carbacyclin induces cardiomyocyte proliferation via a PPARδ/PDK1/p308Akt/GSK3β/β-catenin-pathway and that activated PPARδ signaling after myocardial infarction (MI) induces cardiomyocyte cell cycle activity and improves scarring as well as cardiac function. The gene discussed is PPARD; the disease is myocardial infarction.