Due to its biocompatibility and biodegradability, collagen has numerous biomedical applications. Researchers have highlighted that collagen hydrogels are the best candidate materials for making dressings. This is due to their three-dimensional structure, similar to that of the skin's extracellular matrix, and their moisturizing properties, ensuring that wounds benefit from a moist environment conducive to healing.
Moreover, when applied as a dressing, collagen serves as a natural scaffold and a substrate for the growth of new tissues. It provides the wound with an alternative source of collagen that can be degraded by matrix metalloproteinases (MMPs) as a sacrificial substrate, allowing the native endogenous collagen to continue the normal wound healing process. Indeed, the inflammatory phase of healing is associated with high levels of MMPs, which are normally regulated by certain physiological processes. However, sometimes healing gets stalled, leading to the formation of a scar. Collagen can help restore this process. Additionally, it has been shown that this active ingredient possesses anti-inflammatory and immunomodulatory properties, as well as antimicrobial activity, which are useful for supporting healing.
A recent study conducted by ASSAR and his team on rats with dorsal wounds has proven that collagen extracted from Nile Tilapia, a fish, can accelerate wound healing by stimulating the expression of growth factors TGF-β1 and b-FGF, as well as the proliferation of fibroblasts and myofibroblasts. During the study, the rats were divided into two groups: a control group and a collagen-treated group. The wound surfaces were measured over 15 days, and histopathological examinations were performed. Differences were observed as early as the first week, showing that collagen allows for a faster reduction in wound surface area. The graph below, extracted from the article, indicates a significantly greater improvement starting from day 9.
Collagen appears to have healing effects. However, no study has shown that it can reduce already formed human scars.
Less studied, collagen supplementation could also positively impact wound healing. Recent work was conducted with 31 burn patients admitted to the hospital. In addition to clinical treatment, patients were randomly assigned to receive either a collagen-based supplement or an isocaloric placebo for 4 weeks. By week 2, wounds were completely healed in 50% of the patients in the collagen group and in 6.7% of the patients in the control group. By the end of the study, the wounds of all patients in the collagen group and 40% of the patients in the control group were fully healed. Oral collagen intake could thus have a favorable effect on wound healing, which would be interesting to confirm through further studies. However, no data currently supports that it can reduce existing scars.