Stimulatory effect of zinc on insulin-like growth factor-I and transforming growth factor-beta1 production with bone growth of newborn rats.
The effect of zinc, an essential trace element, on insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 production was investigated to determine the role of this metal in bone growth of newborn rats. Femoral-diaphyseal and metaphyseal tissues were obtained between 1 and 28 days after birth of newborn rats, and cultured for 24 h in a serum-free Dulbecco's modified Eagle's medium containing either vehicle or zinc sulfate (10(-6) - 10(-4) M). Protein concentration in the medium was significantly increased by culture with bone tissues of newborn rats with increasing age (14 and 21 days). Medium IGF-I and TGF-beta1 concentration was gradually reduced with increasing age after birth. The presence of zinc (10(-5) and 10(-4) M) caused a significant increase in protein, IGF-I, and TGF-beta1 concentrations in the medium cultured with the diaphyseal or metaphyseal tissues obtained at 7 and 14 days after birth. The expression of IGF-I and TGF-beta1 mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis in the diaphyseal and metaphyseal tissues cultured for 24 h using rat IGF-I or TGF-beta1-specific primers. These expressions were significantly raised in the presence of zinc (10(-4) M) in culture medium. The present study demonstrates that zinc has a stimulatory effect on IGF-I and TGF-beta1 production in the femoral tissues with bone growth of newborn rats.
Ma
Z J
ZJ
Laboratory of Endocrinology and Molecular Metabolism, Graduate School of Nutritional Sciences, University of Shizuoka, Shizuoka 422-8526, Japan.
Misawa
H
H
Yamaguchi
M
M
D000818:Animals; D000831:Animals, Newborn; D046508:Culture Techniques; D018483:Diaphyses / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D005260:Female; D005269:Femur / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D008297:Male; D014176:Protein Biosynthesis; D011506:Proteins / Q000187:drug effects; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D053773:Transforming Growth Factor beta1; D015032:Zinc / Q000494:pharmacology*
D011506:Proteins; D012333:RNA, Messenger; C508962:Tgfb1 protein, rat; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D007334:Insulin-Like Growth Factor I; D015032:Zinc