Scars, which are evidence of past skin trauma, can be a source of discomfort and self-consciousness. They are difficult to diminish and sometimes last a lifetime. Among the active ingredients that might be able to reduce them is collagen. But can this molecule really act against scars ?
Can collagen help reduce scars?
Published on May 23, 2024, by Pauline, Chemical Engineer — 5 min of reading
Themes:
Does collagen have healing effects?
The collagen is a protein found in the body, particularly in the skin. In interaction with elastin and glycosaminoglycans, collagen fibres ensure the maintenance of the dermis's firmness and resistance, thus providing the skin with the suppleness and tone it needs. This molecule also enables the regeneration of connective tissues and is involved in wound healing.
This process involves a cascade of reactions and is notably characterised by the accumulation of platelets, controlled inflammation, fibroblast proliferation, cellular contraction, angiogenesis, and re-epithelialisation. All these phenomena ultimately lead to scar formation and wound remodelling. Collagen is present in each of these phases of healing due to its chemotactic role. Indeed, it attracts cells such as fibroblasts and keratinocytes, which promotes the removal of dead tissue, angiogenesis, and re-epithelialisation.
External Use of Collagen: Can It Diminish Scars?
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 hydrating properties, ensuring that wounds benefit from a moist environment conducive to healing.
Moreover, when applied as a dressing, collagen acts 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 is stalled, leading to the formation of a scar. Collagen can help to 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 demonstrated 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 from 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 from day 9 onwards.
Collagen appears to have healing effects. However, no study has yet shown that it can reduce already formed human scars.
Somewhat less studied, collagen supplementation could also positively impact wound healing. Recent research was conducted with 31 individuals suffering from burns who were 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 favourable effect on wound healing, which would be interesting to confirm through further studies. However, no data currently supports the claim that it can reduce existing scars.
Effect of applying a Tilapia collagen extract on wound area contraction in rats.
Source: ASSAR D. & al. Collagen extract obtained from Nile tilapia (Oreochromis niloticus L.) skin accelerates wound healing in a rat model by upregulating the expression of VEGF, bFGF, and α-SMA genes. BMC Veterinary Research (2020).
BATHIA A. & al. Collagen: Its Role in Wound Healing. Podiatry Management (2014).
ASSAR D. & al. Collagen extract obtained from Nile tilapia (Oreochromis niloticus L.) skin accelerates wound healing in a rat model by upregulating the expression of VEGF, bFGF, and α-SMA genes. BMC Veterinary Research (2020).
HOSSEINZADEH-ATTAR M. & al. The effect of a hydrolyzed collagen-based supplement on wound healing in patients with burns: A randomized double-blind pilot clinical trial. Burns (2020).
HUDA N. & al. Extraction and Characterization of Bioactive Fish By-Product Collagen as Promising for Potential Wound Healing Agent in Pharmaceutical Applications: Current Trend and Future Perspective. International Journal of Food Science (2022).
