Evaluation of the anti-oxidative and ROS scavenging properties of biomaterials coated with epigallocatechin gallate for tissue engineering

In tissue engineering, excessively generated reactive oxygen species (ROS) during biomaterial implantation or cell transplantation is a one of major causes of diminishing therapeutic effects. In this study, we prepared biomaterial surfaces coated with antioxidant epigallocatechin gallate (EGCG) and metal ions, and evaluated their anti-oxidative and ROS scavenging properties. We revealed that EGCG-coating on polycaprolactone (PCL) film surface increased hydrophilicity and anti-oxidative properties as a function of total phenol content (TPC) potentially due to the increase in phenolic -OH and π-electrons from structural maintenance and directly removed the hydrogen peroxide (H₂O₂) by resonance-stabilization. Furthermore, EGCG-coated PCL film increased attachment, spreading area, and viability of human adipose-derived stem cells (hADSCs) against H₂O₂ treatment while stimulated the cellular signaling to reduce apoptotic gene and enhance anti-oxidative enzyme expression. Further, we applied EGCG coating on the surface of poly-L-lactic acid (PLLA) fibers. Spheroids incorporating EGCG-coated PLLA fibers were able to maintain their shape and showed improved viability and anti-oxidative activities in response to H₂O₂-induced oxidative stress than control spheroids. Therefore, metal-phenolic network (MPN) coating of EGCG is a suitable method to impart the anti-oxidative properties to biomaterials by evaluating the structural properties and biological effects.