title: The effect of platelet-rich plasma on patterns of gene expression in a dog model of anterior cruciate ligament reconstruction.
abstract: BACKGROUND
  Autologous platelet-rich plasma (PRP) has been investigated as a potential promoter of tendon healing and has an enhancing effect on the anterior cruciate ligament (ACL) graft maturation process. However, the influence of PRP on the synthesis and degradation of the extracellular matrix during the ACL graft remodeling process has never been investigated.
  
  
  METHODS
  Healthy and mature beagle dogs were randomly assigned to one of four groups: in group I (PRP group), ACL grafts were treated with PRP; in group II (control group), ACL grafts were treated with saline; in group III (sham group), only the knee joints were exposed; in group IV (normal control group), no surgery was performed to the knees. Ligament tissue was dissected at 2, 6, and 12 wk after surgery, and real-time PCR was performed using primers for growth factor-β1 (TGF-β1), collagen type1A1 (COL1Al), collagen type3A1 (COL3A1), decorin, biglycan, matrix metalloproteinase-1 (MMP-1), matrix metalloproteinase-13 (MMP-13), and tissue inhibitor of metalloproteinase-1 (TIMP-1).
  
  
  RESULTS
  In group I, the messenger RNA (mRNA) levels of collagen type 1A1, biglycan, and MMP-1 all increased 2, 6, and 12 wk after surgery, compared with group II (P < 0.05). At 2 and 6 wk after surgery, increased levels of COL3A1, MMP-1, and MMP-13 mRNA were also detected in group I (P < 0.05). Increased levels of TGF-β1 mRNA was observed at 6 and 12 wk in group I after surgery (P < 0.05).
  
  
  CONCLUSIONS
  During the graft remodeling process, we observed a time-dependent change of gene expression following ACL reconstruction surgery. Furthermore, our results demonstrate that PRP alters the expression of some target genes at certain time points, especially during the early stages of graft remodeling, which might explain the enhancing effect of PRP on the ACL graft maturation process.
authors.affiliation: Department of Arthroscopic Surgery, Sixth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: Xie
authors.forename: Hua
authors.initials: H
authors.lastname: Wu
authors.forename: Song
authors.initials: S
authors.lastname: Zhao
authors.forename: Guoming
authors.initials: G
authors.lastname: Xie
authors.forename: Xiaoqiao
authors.initials: X
authors.lastname: Huangfu
authors.forename: Jinzhong
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000818:Animals; D059549:Anterior Cruciate Ligament Reconstruction; D058578:Biglycan / Q000235:genetics; D024042:Collagen Type I / Q000235:genetics; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III / Q000235:genetics; D058575:Decorin / Q000235:genetics; D004285:Dogs; D005786:Gene Expression Regulation; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000235:genetics; D023421:Models, Animal; D053657:Platelet-Rich Plasma / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics; D053773:Transforming Growth Factor beta1 / Q000235:genetics
chemical_list: D058578:Biglycan; D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III; D058575:Decorin; D012333:RNA, Messenger; D019715:Tissue Inhibitor of Metalloproteinase-1; D053773:Transforming Growth Factor beta1; D020781:Matrix Metalloproteinase 1