PRP (platelet-rich plasma) — Autologous Growth Factor Therapy
Platelet-rich plasma (PRP) is an autologous biologic concentrate derived from whole blood that is enriched with platelets and growth factors. In longevity and regenerative medicine, it is primarily utilised to accelerate tissue repair, combat local senescence, and reduce inflammation in conditions like osteoarthritis and skin aging.
Mechanism of Action
PRP delivers a supraphysiologic concentration of alpha-granules containing key growth factors, including PDGF, TGF-β, VEGF, and IGF-1. Upon activation, these factors bind to local cellular receptors, stimulating intracellular signalling cascades such as the PI3K/Akt and MAPK pathways. This promotes cellular proliferation, angiogenesis, and extracellular matrix synthesis while modulating the local inflammatory response. In joint tissues, PRP has been shown to downregulate NF-κB signalling and reduce the expression of pro-inflammatory cytokines like IL-1β and TNF-α, thereby mitigating chondrocyte apoptosis and matrix degradation.
Human Trial Evidence
PRP has been extensively studied in human clinical trials, particularly for musculoskeletal conditions and dermatology. Multiple double-blind, randomized controlled trials have demonstrated its efficacy in reducing pain and improving function in mild-to-moderate knee osteoarthritis, often outperforming hyaluronic acid or corticosteroid injections. In aesthetic medicine, clinical trials show that PRP injections stimulate neocollagenesis and improve skin texture, though standardisation of preparation protocols remains a significant challenge across studies.
Dosing Protocol
As a procedure, PRP protocols vary widely based on the target tissue and preparation system. For knee osteoarthritis, a standard protocol involves 1 to 3 intra-articular injections of 3–8 mL of leukocyte-poor PRP, spaced 1 to 3 weeks apart. For skin rejuvenation, multiple intradermal micro-injections are typically administered across 3 sessions spaced 4 weeks apart.
Safety & Contraindications
Since PRP is an autologous therapy, the risk of allergic reaction or immune rejection is virtually eliminated. Common adverse effects are mild and localized, including temporary pain, swelling, and bruising at the injection site. Contraindications include critical thrombocytopenia, hemodynamic instability, active local infections, and certain malignancies.