Abstract P486: Decellularized Extracellular Matrix Microparticles Promote Heart Regeneration And Neovascularization In Post-mi Mice
Hypothesis and objective: We hypothesize that solid hydrogel particles will improve therapeutic efficacy of hydrogels derived from decellularized fetal hearts (dECM) on myocardial infarction (MI). In this study we developed dECM microparticles (MPs) to compare with liquid hydrogel. The objectives are 1) develop dECM MPs for increased stability at site of injection; 2) establish reduced degradation in vivo ; and 3) evaluate potential regenerative benefits from dispersed particles of dECM. Methods: Microparticles were generated by electrospray of solubilized dECM. Microparticles were injected immediately after coronary artery ligation in adolescent mice. Echocardiography and histology were conducted 21days post-MI. Results: Electrospray with emulsification produced solid dECM microparticles ranging in size from nanometers to microns depending on parameters. The dECM MPs showed prolonged release of proteins and decreased degradation rate in vitro compared to dECM hydrogel. The dECM MPs were observed to protect cardiac function (Fig. 1), lower fibrosis, stimulate cardiogenesis, and promote vascularization compared to MI control. Cardiogenesis and neovascularization were observed with dECM microparticles treatment compared to hydrogel treatment (Fig. 2). This study suggests the solid dECM particles provides unique advantages as an injectable therapy directed at the ischemic heart.