Curcumin-laden ECM-mimicking microfibers assemble with mesenchymal stem cells to generate heterospheroids and enhance cell viability and function

Extracellular matrix (ECM) is an integral part of cell biology that not only provides physical stability to cells, but also aids in cell-to-cell and cell-to-essential-protein interactions in the cellular microenvironment. To mimic the natural ECM conditions, we prepared morphologically similar artificial polymeric microfibers and used polydopamine to coat them with collagen to enhance cell–polymeric fiber interactions. Heterospheroids (HSs) of ECM-mimicking microfibers and mesenchymal stem cells (MSCs) were prepared using the spontaneous aggregation method. The results revealed well-organized MSC-microfiber HSs that enhanced the viability of the MSCs. In addition, when curcumin, an antioxidant drug, was loaded into the microfibers and HSs were prepared, the viability of the MSCs was further enhanced, as revealed by a reduction in the expression of apoptotic protein Bax. Furthermore, the expression of anti-apoptotic proteins Bcl-2 and HO-1 increased significantly in the HSs containing the drug-loaded microfibers. Overall, our study suggests a novel strategy for improving the success of MSC therapy using ECM-mimicking artificial microfibers.