Platelet‐rich plasma (PRP) impairs the craniofacial bone repair associated with its elevated TGF‐β levels and modulates the co‐expression between collagen III and α‐smooth muscle actin

Abstract

Transforming growth factor-b (TGF-b) is considered the main inducer of both the a-smooth muscle actin (a-SMA) phenotype and collagen synthesis and deposition and plays a significant role in the tissue repair and the development of fibrosis. Since the PRP constitutes an important source of TGF-b and its efficacy on the craniofacial bone repair remains controversy, the aim of this study was to evaluate the effect of PRP in the presence of levels of TGF-b on PRP samples, as well as in the presence of collagen III and a-SMAþ cells, while comparing these results by means of a histomorphometric analysis of the bone matrix and fibrous deposition on the bone repair. Four bone defects of 16 mm 2 were created on the calvarium of 21 rabbits. The surgical defects were treated with either particulate autograft, particulate autograft mixed with PRP and PRP alone. Animals were euthanized at 15, 30, and 45 days postoperative. Histomorphometric and immunohistochemical analyses were performed to assess repair time, as well as the expression of collagen III, and a-SMA. The histomorphometric results demonstrated intensive deposition of fibrous tissue while hinder bone deposition occurred in PRP groups. These results coincided with higher values of the TGF-b on the PRP sample, also larger occurrence of diffuse collagen III deposition and higher presence of a-SMAþ cells spread among the fibrous tissue. Thus, the higher levels of TGF-b associated with the both expression of collagen III and a-SMA on defect treated with PRP suggest that its biomaterial induce an effect that can be considered similarly to a fibroproliferative disorder. ß

Human platelet‐rich plasma stimulates migration and chondrogenic differentiation of human subchondral progenitor cells

“…PRP contains high amounts of TGFB (up to 260 ng/ml) 36 and since all isoforms of TGFB induce chondrogenesis of mesenchymal stem cells, 22,37 it is likely that TGFB available in PRP may induce chondrogenesis of human progenitor cells. The lack of knowledge about which growth factors and at which doses exert the PRP effect is a limitation of the study.…”

Platelet Preparations for Use in Facial Rejuvenation and Wound Healing: A Critical Review of Current Literature

“…The greatest effect was when b-FGF was added to L-PRP [33]. Giovanni et al on the other hand, showed in four different studies published from 2010 to 2014 that use of PRP and L-PRP in animal calvarial bone defects hindered bone deposition, enhanced fibrous tissue formation, and also enhanced type III to type I collagen ratio [34][35][36][37].…”

“…chemotaxis Giovanni et al [36] Diminished bone repair, increased fibrous tissue deposition, increased type III: type I collagen ration…”

Platelet Rich Plasma (PRP) Produces an Atherofibrotic Histophenotype During Craniofacial Bone Repair Due to Changes of Immunohistochemical Expression of Erk1/2, p38α/β, Adiponectin and Elevated Presence of Cells Exhibiting B-scavenger Receptor (CD36+)

“…hypothesis suggests that the greater synthesis of a platelet growth factor (TGF-β1) may induce the formation of actin myofilaments in the cells that compose the reparative sites, a fact that also contributes to the occurrence of pathological fibrosis (4).…”

“…The favorable use of PRP for osteogenesis has been substantiated on the hypothesis that the platelets produce growth factors that modulate the synthesis and deposition of extracellular matrix (ECM) and angiogenesis, and promotes chemotaxis of osteoprogenitor cells and their differentiation into osteoblasts (3). Nonetheless, despite this remarkable biological action, it has been claimed that the presence of PRP may not only impair osteogenesis, but also produce an abnormal histophenotype during craniofacial bone repair (4,5).…”