The use of PRP in hair growth
Platelet rich plasma (PRP) contains a high concentration of thrombocytes. PRP carries various growth factors (GF) that stimulate cell proliferation and differentiation. PRP is known to carry more than 20 GFs, including platelet-derived growth factor, fibroblast growth factor, hepatocyte growth factor, transforming growth factor and vascular endothelial growth factor. Many of these growth factors bind to heparin.
Recent work has demonstrated the role of PRP in bone grafts, teeth osteosynthesis, and wound healing. In 2006, Uebel and colleague reported a new application of PRP for male pattern baldness. Implanting follicular units with PRP raised the hair yield rate, probably because of the partial effects of GFs in PRP. The action of GFs on the germinative hair cycle has been studied in embryologic and adult phases, but no clinical trial or experimental protocol has previously verified the efficacy of those factors in the growth and density of hair after subcutaneous injection into the thinning area.
A group of plastic surgeons in Japan were curious to find out whether the use of PRP combined with a low molecular weight heparin, dalteparin will enhance hair growth more so than PRP alone. As reported in the Dermatologic Surgery journal in December 2011, a study done in Japan showed PRP facilitated hair growth and that the use of dalteparin and protamine microparticles (D/P MPs) with PRP provided additional hair growth.
It was a study involving 26 volunteers with thin hair who received five local treatments of PRP with D/P MPs (13 participants), or PRP and saline (control, 13 participants) at 2-3 weekly intervals and were evaluated for 12 weeks. Injected areas comprised frontal or parietal sites with fine lanugo-like hair. Experimental and control areas were photographed. Consenting participants underwent biopsies for histologic examination.
The results showed differences in hair cross-sections but not in hair numbers in the two groups. The addition of D/P MPs to PRP resulted in significant stimulation in hair cross-section. Microscopic findings showed thickened epithelium, proliferation of collagen fibers and fibroblasts, and increased vessels around follicles. Because all components namely dalteparin, protamine and PRP are in clinical use, safety for clinical use appears likely.
Reference: Takikawa M, Nakamura S, Nakamura S, Ishirara M, et al. Enhanced Effect of Platelet-Rich Plasma Containing a New Carrier on Hair Growth. Dermatological Surgery 2011; vol 37, number 12. 1721-1729.