Wound healing

Wound healing works by sealing a break in the skin in stages: a clot forms within minutes, immune cells clear bacteria and dead tissue over the next few days, keratinocytes crawl across the gap to restore a barrier, and fibroblasts rebuild and then remodel the collagen beneath it over months. It is the skin-specific case of the general tissue repair programme.

How it works

Clot. Platelets aggregate on exposed collagen and fibrin cross-links into a temporary matrix that doubles as a scaffold for incoming cells.

Debridement. Neutrophils, then macrophages, remove bacteria and dead tissue. This is inflammation doing its intended job; a wound cannot skip it.

Re-epithelialisation. Keratinocytes at the wound edge lose their attachments and migrate across the wound bed. Because they need a moist surface to move over, a covered wound closes faster than one left to form a hard scab.

Granulation. Fibroblasts fill the defect with collagen and glycosaminoglycans while new capillaries grow in — the red, bumpy tissue the process is named after. See angiogenesis.

Contraction and remodelling. Myofibroblasts pull the edges together, and collagen is progressively replaced and realigned. Scar tissue reaches roughly 80% of the tensile strength of intact skin and never regrows hair follicles or sweat glands.

Why some wounds stall

A chronic wound is one stuck in the inflammatory stage. The usual causes are poor perfusion (peripheral arterial disease), repeated pressure, uncontrolled diabetes, infection, or a persistent biofilm. Moisture balance, offloading, and treating the underlying cause matter more than any topical agent.

Why peptides care

• GHK-Cu is the most directly relevant compound here: it is used as a topical cosmetic ingredient (INCI name Copper Tripeptide-1) and the strongest human evidence for it comes from small topical trials on skin remodelling.
• BPC-157 is studied for accelerated wound closure and gastrointestinal mucosal healing, almost entirely in rodents.
• TB-500 is described as accelerating dermal and epithelial wound closure with reduced scarring in preclinical models.

None of these is an approved wound-care drug. Read each article’s evidence grades before drawing a conclusion.

Medical note

Deep, dirty, or non-healing wounds need clinical assessment. Nothing on this page is medical advice — see the medical disclaimer.