Space flight and insulin-like growth factor-I signaling in rat osteoblasts.
The primary culture of rat osteoblasts was treated with 1alpha,25 dihydroxyvitamin D(3) and fixed with guanidine isothiocyanate solution during a space shuttle flight. The mRNA levels were analyzed by quantitative reverse transcription-polymerase chain reaction. Microgravity decreased the mRNA levels of insulin-like growth factor-I (IGF-I) and increased reciprocally the IGF-I receptor mRNA levels, as compared to the ground (1 x g) control. Microgravity completely suppressed the mRNA expression of the insulin receptor substrate-1, the postreceptor signaling molecule of IGF-I. Microgravity might deteriorate the action and signaling of IGF-I in rat osteoblasts.
Kumei
Yasuhiro
Y
Graduate School of Tokyo Medical and Dental University, Tokyo 113-8549, Japan. kumei.bch@tmd.ac.jp
Nakamura
Hiroshi
H
Morita
Sadao
S
Akiyama
Hideo
H
Hirano
Masahiko
M
Ohya
Kei'chi
K
Shinomiya
Ken'ichi
K
Shimokawa
Hitoyata
H
D000818:Animals; D002117:Calcitriol / Q000494:pharmacology; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000502:physiology*; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D010006:Osteoblasts / Q000187:drug effects / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D013026:Space Flight; D014893:Weightlessness
D012333:RNA, Messenger; D007334:Insulin-Like Growth Factor I; D002117:Calcitriol