Evaluation of the Pro-Angiogenic Effect in Chicken Embryo Chorioallantoic Membrane (CAM) Model and the In Vivo Wound Healing Potential of the Moroccan Polysaccharide-Rich Algae Osmundea pinnatifida

Various methods have been studied to speed up the wound healing process. Promoting the rapid development of blood vessels, also known as angiogenesis, is essential as this significantly accelerates skin regeneration. This study identified a polysaccharide from the red alga Osmundea pinnatifida (PSOP) that promotes angiogenesis and accelerates wound healing. Firstly, we analyzed the structural characteristics of PSOP using various techniques such as UV-visible spectrum, Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (X-RD), scanning electron microscopy (SEM), and high-performance liquid chromatography coupled to refractive index detector (HPLC-RID). We also evaluated the antioxidant properties of PSOP in vitro using tests for DPPH free radical scavenging capacity, iron reduction capacity (RPA), and total antioxidant capacity (TAC). Additionally, we observed a significant increase in new blood vessel formation in the chorioallantoic membrane model (CAM assay) using a fertilized hen egg, indicating the pro-angiogenic effect of PSOP. Furthermore, we tested the wound-healing potential of PSOP hydrogel in vivo using excision wounds in the Wistar rat model. The results showed a notable acceleration of wound closure and an improvement in tissue regeneration and collagen deposition quality within 11 days, indicating the strong wound-healing activity of PSOP. Our computational study suggested that the PSOP units bind to cyclooxygenase 2 (COX-2) and vascular endothelial growth factor (VEGF) with acceptable affinities and interactions, which might explain the observed beneficial wound healing properties and the pro-angiogenic effect seen in the experimental assays. Our findings support using the polysaccharide PSOP for wound treatment due to its antioxidant and pro-angiogenic potential.