Assessing New Collagen Therapies for Wound Healing: A Murine Model Approach.

Collagen proteins play important roles in wound healing and are of great interest in regenerative medicine. This study evaluated the efficacy of new collagen-based products and compared them to commercial products in a murine model of cutaneous healing. Circular excisional defects were generated on 72 Wistar rats. Six study groups were established according to the administered collagen treatment: Control (without treatment), SD-C (semidenatured), Catrix, Hy-C (hydrolyzed), N-C (native) and Helix3-CP. Seven and eighteen days post-surgery, animals were euthanized. Wound closure was macroscopically assessed by taking zenithal images of the defects. Morphological, histological and immunohistochemical studies were performed to evaluate the healing process. After 7 days, open areas and degree of epithelialization were similar among the groups. Significant differences were observed in contraction between control and the N-C and Helix3-CP groups. Untreated animals exhibited a more pronounced granulation tissue with a high number of inflammatory cells and a disorganised extracellular matrix with type III collagen deposition. After 18 days, animals treated with new collagen (Hy-C and N-C) exhibited accelerated wound closure, increased epithelialization and a more organised granulation tissue. Local administration of new collagen treatments promotes the progression of the reparative process and significantly accelerates wound closure compared with nontreated wounds.