Assessment of electromechanically stimulated bone marrow stem cells seeded acellular cardiac patch in a rat myocardial infarct model

In this study, we evaluated cardiomyogenic differentiation of electromechanically stimulated rat bone marrow-derived stem cells (rt-BMSCs) on an acellular bovine pericardium (aBP) and we looked at the functioning of this engineered patch in a rat myocardial infarct (MI) model. aBP was prepared using a detergent-based decellularization procedure followed by rt-BMSCs seeding, and electrical, mechanical, or electromechanical stimulations (3 millisecond pulses of 5 V cm -1 at 1 Hz, 5% stretching) to enhance cardiomyogenic differentiation. Furthermore, the electromechanically stimulated patch was applied to the MI region over 3 weeks. After this period, the retrieved patch and infarct region were evaluated for the presence of calcification, inflammatory reaction (CD68), patch to host tissue cell migration, and structural sarcomere protein expressions. In conjunction with any sign of calcification, a higher number of BrdU-labelled cells, and a low level of CD68 positive cells were observed in the infarct region under electromechanically stimulated conditions compared with static conditions. More importantly, MHC, SAC, Troponin T, and N-cad positive cells were observed in both infarct region, and retrieved engineered patch after 3 weeks. In a clear alignment with other results, our developed acellular patch promoted the expression of cardiomyogenic differentiation factors under electromechanical stimulation. Our engineered patch showed a successful integration with the host tissue followed by the cell migration to the infarct region.