Differential expression of vascular endothelial growth factor in glucocorticoid-related osteonecrosis of the femoral head.
VEGF plays a role in bone remodeling. Ingrowth of reparative arterioles can be observed in late-stage osteonecrosis. To explore the reparative processes, we quantified the most important angiogenesis factor (VEGF) in different zones of late-stage glucocorticoid-induced osteonecrosis. We treated primary nonosteonecrosis osteoblasts with glucocorticoids in vitro as a model for the bone cells in early-stage steroid-related osteonecrosis. We obtained six late-stage (ARCO Stage IV) osteonecrosis femoral heads and six osteoarthritic femoral heads during THA. The expression of vascular endothelial growth factor was analyzed by reverse-transcription PCR, ELISA, or immunohistochemistry. Osteoblasts from the reactive interface (penumbra) of osteonecrosis femoral heads exhibited increased immunoreactivity to VEGF compared to those from the periphery. ELISA confirmed VEGF upregulation in the penumbra from osteonecrosis femoral heads. Primary osteoblasts derived from osteoarthritic femoral heads exhibited downregulation of VEGF after 24 hours of coincubation with glucocorticoids. The increase in VEGF in the reactive interface (penumbra) of osteonecrosis in late-stage femoral head may reflect a secondary phenomenon. The observed high amount of VEGF in later-stage osteonecrosis might stimulate the ingrowth of reparative arterioles into the femoral head.
Varoga
Deike
D
Department of Orthopaedic and Trauma Surgery, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany.
Drescher
Wolf
W
Pufe
Melanie
M
Groth
Godo
G
Pufe
Thomas
T
D000328:Adult; D002478:Cells, Cultured; D003907:Dexamethasone / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D005270:Femur Head / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D005271:Femur Head Necrosis / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D005938:Glucocorticoids / Q000009:adverse effects*; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D018919:Neovascularization, Physiologic / Q000187:drug effects; D015207:Osteoarthritis, Hip / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D010011:Osteocytes / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012720:Severity of Illness Index; D013997:Time Factors; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
D005938:Glucocorticoids; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D003907:Dexamethasone