Fucoidan in der Knochenregeneration: Von Zellspezifischen Bioaktivitäten zur Entwicklung eines Hydrogelbasierten Trägersystems

Fucoidans are sulfated polysaccharides found in the cell wall of brown algae. Due to their ample effects on angiogenesis, osteogenesis and inflammation, these polysaccharides are promising bioactive compounds for the application in regenerative medicine. However, the chemical structure of fucoidan which determines the bioactivities is dependent on many parameters such as algae species, location, season and extraction technique and can therefore vary tremendously between extracts. Due to the heterogeneity of fucoidan and the largely unknown relation between chemical structure and function, it remains challenging to use fucoidan in a medical context. The presented dissertation investigates the biological activity of different fucoidan extracts on molecular processes relevant for bone tissue regeneration and relates chemical properties of the extracts to the observed bioactivities. Mono- and co-cultures of human outgrowth endothelial cells (OEC) isolated from peripheral blood and human mesenchymal stem cells isolated from cancellous bone and differentiated towards an osteoblast lineage (MSC) were used as cell model systems to mimic the bone tissue environment. To come one step closer to the utilization of fucoidan as a therapeutic agent, a thermosensitive chitosan-collagen hydrogel-based delivery system with incorporated fucoidan was developed