In Vivo Model of Bone Regeneration with Aspirin Cross-linked O-carboxymethyl Chitosan Hydrogel Loaded with Adipose Derived-Stem Cells

Aspirin, also known as acetylsalicylic acid (ASA), a hydrophilic substance, was selected as a cross-linker to create the three-dimensional structure of the chitosan hydrogel. The main objective of this research is to incorporate aspirin as a crosslinker in hydrogels to enhance bone regeneration. O-carboxymethyl chitosan (O-CMC) was synthesized. The 0.09 O-CMC hydrogel was prepared and mixed with an aspirin solution at a concentration of 0.05 g/ml. The resulting gel composite O-CMC/ASA with and without human adipose-derived stem cell (ADSC) was then used to fill 8-mm skull defects in the Wistar model for 4 and 8 weeks, enabling an evaluation of its potential to stimulate bone formation in vivo. Histological examination and CT revealed that the hydrogel O-CMC/ASA/ADSCs promoted the migration and proliferation of ADSCs, leading to a significant increase in new bone formation compared with hydrogel O-CMC.