When we’re injured, the body has a remarkable natural ability to repair itself — though sometimes that process needs support to heal as effectively as possible. Injuries vary widely, from a torn rotator cuff or exercise-related strain to paresthesia and spasticity following a stroke. Regardless of the cause, the body’s underlying healing response follows a similar biological pathway.
When tissue is damaged — whether from a penetrating injury or a hypoxic event (reduced oxygen supply) — the body releases cytokines, signaling proteins that trigger the healing cascade. These cytokines recruit white blood cells and platelets to the site of injury. Platelets carry surface receptors called integrins, which detect tissue damage and guide the platelets directly to the affected area. Once there, white blood cells and platelets work together to protect against infection, help control any active bleeding, and release additional signaling proteins — including interleukins (IL-1, IL-6, IL-8) and growth factors — that begin coordinating the tissue repair process.
These cytokines also recruit satellite cells and progenitor cells to the injury site, initiating the rebuilding process. Once the surrounding structural (stromal) tissue is damaged, these cells begin working to repair and regenerate the area. As part of this process, transforming growth factor beta-1 (TGF-β1) stimulates myogenic cells and muscle-derived stem cells to differentiate into myofibroblasts, which synthesize collagen — a key step in forming new tissue, though this same process can also lead to fibrosis (scar tissue formation) if not well-regulated.
Fibrosis plays a dual role in healing: while it helps restore the structural integrity of injured tissue, it can also create limitations — including contractures, spasticity, or the visible puckering effect of a scar. In some cases, the body doesn’t mount a complete enough healing response, leaving a person with lingering chronic pain or paresthesia (abnormal nerve sensations).
Chronic pain is something most people experience at some point — whether from tennis elbow, a joint injury from lifting, a muscle tear, post-stroke effects, or the cumulative impact of repetitive daily movements. Rather than relying on treatments that only temporarily mask discomfort, one of the body’s most effective natural repair mechanisms involves activating its own resident stem and progenitor cells to address the underlying damage. These cells rely on cytokines and growth factors to know where to go and what to do — signaling molecules released either when a damaged cell’s contents leak into surrounding tissue, or when a cell is stimulated to release its internal granules. This is where platelets play a particularly important role in wound healing, given the volume and variety of growth factors stored within their cytoplasmic granules.