Insulin-like growth factor-1 treatment prevents anti-Fas antibody-induced apoptosis in endplate chondrocytes.
METHODS
In vitro investigation of vertebral endplate chondrocyte apoptosis.


OBJECTIVE
To determine whether Fas antibody caused apoptosis in endplate chondrocytes, and whether insulin-like growth factor-1 (IGF-1) inhibited this effect. Integrin-alpha1 and focal adhesion kinase (FAK) expression in conjunction with apoptosis was also investigated.


BACKGROUND
Binding of Fas antibody to Fas mimics Fas-FasL ligation, which causes apoptosis. IGF-1 has been shown to have anti-apoptotic effects.


METHODS
Rat cervical endplate chondrocytes were cultured and treated with Fas antibody, with or without IGF-1. Cellular morphology was examined by microscopy. Apoptotic changes were evaluated by transmission electron microscopy, TUNEL staining, and immunostaining. Apoptosis-induced changes in the expression of integrin-alpha1 chain and FAK were also investigated.


RESULTS
Endplate chondrocytes were able to be cultured; a chondrocytic phenotype was maintained. Fas antibody induced apoptosis in endplate chondrocytes; this was confirmed by TUNEL staining. Bcl-2 expression was decreased by Fas antibody, while Bax expression increased. Integrin-alpha1 and FAK expression was decreased by Fas antibody. IGF-1 treatment inhibited these Fas antibody-induced changes.


CONCLUSIONS
Fas antibody induces apoptosis and decreases Integrin-alpha1 and FAK expression in cultured endplate chondrocytes; IGF-1 is protective against these changes.
Institute of Spine, Shanghai University of Traditional Chinese Medicine, Shanghai, China. Yongjun_wang@urmc.rochester.edu
Yong-Jun
YJ
Wang
Qi
Q
Shi
Peng
P
Sun
Quan
Q
Zhou
Michael
M
Darowish
Tian-Fang
TF
Li
Yu-Feng
YF
Dong
William W
WW
Lu
John C Y
JC
Leong
D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism / Q000502:physiology*; D058846:Antibodies, Monoclonal, Murine-Derived; D000915:Antibody Affinity; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D053222:Fas Ligand Protein; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D039423:Integrin alpha1 / Q000096:biosynthesis; D008562:Membrane Glycoproteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D048069:Tumor Necrosis Factors / Q000378:metabolism; D019014:fas Receptor / Q000276:immunology* / Q000378:metabolism
D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D053222:Fas Ligand Protein; C505662:Faslg protein, rat; D039423:Integrin alpha1; D008562:Membrane Glycoproteins; D048069:Tumor Necrosis Factors; C411023:anti-Fas monoclonal antibody; D019014:fas Receptor; D007334:Insulin-Like Growth Factor I