Deferoxamine-Loaded Trilayer Scaffold Containing Propolis and Sulfated Polysaccharides Promotes <i>In Vivo</i> Wound Healing through Angiogenesis Stimulation

The skin exhibits a hierarchical structure, and the application of tissue engineering techniques is recommended for the treatment of severe cutaneous injuries. To biologically mimic the structural characteristics of the distinct layers of the skin, the utilization of multilayered scaffolds has become a prominent approach. In the current study, an asymmetric trilayered scaffold was fabricated, consisting of a middle layer (ML) composed of 3D printed poly(vinyl alcohol)-carrageenan (PVA.Crg), a top layer (TL) of nanofibrous polycaprolactone-propolis (PCL.Pp), and a bottom layer (BL) of poly(vinyl alcohol)-fucoidan-deferoxamine (PVA.Fu.Def) nanofibers. It was indicated that the tensile strength and elastic modulus of the trilayer scaffold were significantly higher compared to other samples. The <i>in vitro</i> degradation rate of the studied scaffolds as well as the release of Def from the trilayer scaffold after 7 days were quantified within the range of 36-40 and 91.1%, respectively. The release of Def did not induce cytotoxicity and chicken chorioallantoic membrane assay revealed that the release of Def remarkably enhanced angiogenesis. Furthermore, the <i>in vivo</i> examinations exhibited the fastest re-epithelialization in the group treated with the trilayer scaffold containing Def. The findings of this study suggest the potential application of the fabricated trilayer scaffold as a skin substitute or wound dressing.