The whole wound healing procedure generally includes four stages which named as hemostasis, inflammation, proliferation, and skin remodeling. In the hemostasis stage, the coagulation system is activated after blood vessels constrict and platelets aggregate. Fibrinogen is transformed into insoluble fibrin that forms clots to stop hemorrhaging. In the inflammation stage, bacteria and necrotic tissue are cleared by inflammatory cells. Epithelial cells proliferate and migrate to form epithelial tissue to cover the wound in the proliferation stage. Granulation tissue fills the tissue gap, but epithelialization does not take place. During the final remodeling stage, fresh epidermis and dermis will regenerate to finish the skin repair procedure.
Effects and Mechanisms of Chitosan on Skin Wounds
Chitosan and its derivatives will play roles mainly in the first three stages during wound healing. Firstly, they help stop hemorrhaging by promoting the aggregation of platelets and erythrocytes and inhibiting the dissolution of fibrin in the hemostasis stage; Secondly, they can assist to clear bacteria from the wound during the inflammation stage; Finally, they accelerate skin proliferation via promoting the growth of granulation tissue, which is called proliferation stage. After then, the wound was healed and the skin was remodeled to finish the healing route.
