Alkaline phosphatase and type I collagen gene expressions were reduced by hydroxyl radical-treated fibronectin substratum.
The influence of fibronectin (FN) substratum treated with hydroxyl radicals (.OH) generated by the H2O2-Cu2+ systems on osteoblast cells was studied. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that FN was degradated and/or modified by .OH treatment. The calcified bone nodule formation of osteoblast cells cultured on .OH treated FN-coated wells was significantly lower compared to those on intact FN-coated wells. Alkaline phosphatase (ALP) activity and the secretion of type I collagen were reduced by .OH-treated FN. By RT-PCR mRNA levels of ALP and type I collagen genes were also diminished. These findings suggested that the .OH damaged FN molecules and reduced the bone formation of osteoblast cells via inhibition of proliferation and/or differentiation of osteoblast progenitors and the calcification process.
Hosoya
S
S
Department of Biochemistry, Nihon University School of Dentistry at Matsudo, Sakaecho-Nishi, Matsudo, Chiba, 271-8587, Japan.
Suzuki
H
H
Yamamoto
M
M
Kobayashi
K
K
Abiko
Y
Y
D000469:Alkaline Phosphatase / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D003094:Collagen / Q000235:genetics*; D017931:DNA Primers; D005353:Fibronectins / Q000378:metabolism*; D017665:Hydroxyl Radical; D010006:Osteoblasts / Q000201:enzymology / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D005353:Fibronectins; D012333:RNA, Messenger; D017665:Hydroxyl Radical; D003094:Collagen; D000469:Alkaline Phosphatase