Tendon Healing
The biological repair of damaged tendon tissue, proceeding through inflammatory, proliferative, and remodelling phases over 6-12+ months. Tendons heal slowly due to limited blood supply and low cellular activity. Several research peptides are investigated for potential to accelerate tendon repair in preclinical models.
Technical Context
Tendon healing proceeds through: inflammatory phase (0-7 days: neutrophils then macrophages infiltrate, cytokines recruit fibroblasts and progenitor cells), proliferative phase (1-6 weeks: tenocytes/fibroblasts produce type III collagen, granulation tissue forms, neovascularisation occurs), and remodelling phase (6 weeks - 12+ months: type III collagen progressively replaced by type I, collagen fibres align along the axis of mechanical loading, crosslinking increases tensile strength). Key limitation: tendon repair tissue is scar-like (disorganised collagen) rather than regenerative (recreating original tendon architecture), resulting in biomechanically inferior tissue. Healing is slow because: tendons have limited vascularity (blood supply from paratenon, muscle-tendon junction, and bone insertion is sparse in the tendon mid-substance), tenocytes have low metabolic activity, and mechanical loading is required for collagen alignment but can disrupt early repair. Research peptides for tendon healing must demonstrate effects in this specific tissue context, not just generic wound healing models.