The Role of Inflammation in Scar Treatment

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In the tissue repair process, dermal cells are involved, among which papillary fibroblasts play a central role both in tissue repair and in the actual wound healing. These cells mediate fibrosis, participate in inflammatory networks, synthesize the extracellular matrix, and modulate the functions of immune cells.

Scars differ from normal skin aesthetically, morphologically, and functionally. They consist of poorly organized collagen fibers and lack both glands and hair follicles.

Among these, keloids are abnormal scars that develop in areas of the body subject to excessive tension or rigidity. The tissue tends to extend beyond the original wound site irreversibly, sometimes causing itching, inflammation, pain, and psychological discomfort for the patient, especially when located in highly exposed body areas.

How to distinguish keloids from hypertrophic scars?

Hypertrophic scars are characterized by an excess of tissue, presenting as raised above the skin but not exceeding 4 mm in thickness. They appear pink or red in color and may cause itching.

Unlike keloids, hypertrophic scars can regress over time and do not extend beyond the geographical boundaries of the original wound. In contrast, keloids continue to evolve over time, infiltrating the surrounding tissue. What these two types of “pathological” scars share is the persistent presence of an inflammatory state and excessive collagen production.

What is the role of inflammation?

Inflammation is a necessary step in the wound healing process, occurring immediately after tissue damage and microbial invasion.

The primary actors in this phase are inflammatory cells.

Mechanism of action

During the inflammatory phase of a typical wound healing process, immune cells are primarily recruited to prevent the invasion of pathogenic microbes. However, dysregulation of immune cells may alter the wound healing outcome and lead to an abnormal scarring process.

In particular, an excess of macrophages appears to be associated with the formation of abnormal scars due to their involvement both in the production of pro-inflammatory cytokines in the tissue surrounding the wound and in fibrosis.

Pro-inflammatory factors, including IL-6, IL-8, IL-18, chemokine-like factor-1 (CKLF-1), and prostaglandins produced by cyclooxygenase (COX-1), have also been found in significant amounts in keloid tissue.

How to prevent keloids

Inflammation is involved in modulating collagen synthesis, and the intensity of inflammation is positively correlated with the final size of the scar.

Therefore, after ensuring adequate skin hydration to maintain wound elasticity, the application of substances with anti-inflammatory activity appears capable of improving scar formation and preventing keloid development.