title: Relationship of plasma and synovial fluid vascular endothelial growth factor with radiographic severity in primary knee osteoarthritis.
abstract: OBJECTIVE
  Recent evidence suggests that angiogenesis and inflammation contribute to the development and progression of osteoarthritis (OA). The purpose of this study was to investigate vascular endothelial growth factor (VEGF) levels in plasma and synovial fluid of patients with knee OA and to determine the relationship of VEGF levels with disease severity in knee OA.
  
  
  METHODS
  A total of 100 subjects were enrolled in this study (80 knee OA patients and 20 healthy controls). Plasma and synovial fluid VEGF levels were analysed using enzyme-linked immunosorbent assay. VEGF expressions in synovial membrane and articular cartilage samples were assessed using immunohistochemistry.
  
  
  RESULTS
  VEGF level in synovial fluid of knee OA patients was tenfold higher than that in paired plasma (P < 0.001). Both plasma and synovial fluid VEGF exhibited a positive correlation with radiographic severity (r = 0.454 and r = 0.727, P < 0.001, respectively). VEGF expression was highly detectable in synovial lining cells and articular chondrocytes of knee OA patients.
  
  
  CONCLUSIONS
  VEGF levels in both plasma and synovial fluid were positively correlated with the severity of knee OA. Therefore, VEGF may be useful for monitoring OA severity and could play a substantial role in the development and progression of knee OA.
authors.affiliation: Inter-department Program of Biomedical Sciences, Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, 10330, Thailand.
authors.forename: Natthaphon
authors.initials: N
authors.lastname: Saetan
authors.forename: Sittisak
authors.initials: S
authors.lastname: Honsawek
authors.forename: Aree
authors.initials: A
authors.lastname: Tanavalee
authors.forename: Pongsak
authors.initials: P
authors.lastname: Yuktanandana
authors.forename: Surapoj
authors.initials: S
authors.lastname: Meknavin
authors.forename: Srihatach
authors.initials: S
authors.lastname: Ngarmukos
authors.forename: Thanathep
authors.initials: T
authors.lastname: Tanpowpong
authors.forename: Vinai
authors.initials: V
authors.lastname: Parkpian
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D020370:Osteoarthritis, Knee / Q000097:blood / Q000000981:diagnostic imaging* / Q000378:metabolism*; D011859:Radiography; D012720:Severity of Illness Index; D013582:Synovial Fluid / Q000737:chemistry*; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis* / Q000097:blood
chemical_list: D042461:Vascular Endothelial Growth Factor A