Evaluating the effects of autologous platelet lysate on gene expression of bone growth factors and related cytokines secretion in rabbits with bone fracture

Abstract

Although bone substitutes supplemented with platelet derived products are widely used in bone regeneration, the role of platelet lysate (PL) needs to be further elucidated in treatment of bone damages. Accordingly, the aim of this animal study was to evaluate the possible benefits of autologous PL (APL) in fracture healing. Rabbit APL obtained from freeze-thawed platelet suspension and used for treatment of femoral bone damage in 20 rabbits after surgery procedure. Twenty other rabbits with femoral bone damage were assigned to control group which received phosphate-buffered saline (PBS) as therapy. Enzyme linked immunosorbent assay (ELISA) and real-time quantitative polymerase chain reaction (RT-qPCR) used for investigation of the secretion and mRNA expression of interlukein-1 (IL-1), IL-6, tumor necrosis factor alpha (TNF-α) and transforming growth factor beta (TGF-β) cytokines, respectively. The mRNA expression of several other related genes including matrix metalloproteinases-3 (MMP-3) and MMP-13, insulin-like growth factor (IGF), fibroblast growth factors (FGF), vascular endothelial growth factor (VEGF), and platelet-derived growth factor (PDGF), were also evaluated in days 0, 15, 30 and 60 which was higher in APL-treated rabbits than that of the controls. However, secretion of pro-inflammatory cytokines was meaningfully lower than the control group and reduced significantly after two weeks. These observations indicated that factors released from PL and regulation between them could play major roles in bone fracture healing.