Estrogen and parathyroid hormone regulate insulin-like growth factor binding protein-4 in SaOS-2 cells.
The effect of 17beta-estradiol and parathyroid hormone (PTH) on the expression of insulin-like growth factor-binding protein-4 (IGFBP-4) messenger RNA (mRNA) was studied in the cultured human osteoblast-like SaOS-2 cells. Treatment of SaOS-2 cells with PTH for 3 h caused 3.3-fold increase in IGFBP-4 mRNA levels which was determined by reverse transcription-polymerase chain reaction. 17beta-Estradiol had no effect on either the stimulation of mRNA level by PTH or the basal level. Together with our previous report that 17beta-estradiol inhibits the PTH-induced reduction of IGFBP-4 proteolysis in these cells, the results obtained may help to explain the mechanisms of determining IGFBP-4 availability by systemic hormones in osteoblast cells.
Kudo
Y
Y
Department of Obstetrics and Gynecology, Tokyo Women's Medical College, Shinjuku, Japan.
Iwashita
M
M
Iguchi
T
T
Takeda
Y
Y
Hizuka
N
N
Takano
K
K
Muraki
T
T
D015153:Blotting, Western; D002460:Cell Line; D017077:Culture Media, Conditioned; D004958:Estradiol / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D018974:Insulin-Like Growth Factor Binding Protein 4 / Q000235:genetics / Q000378:metabolism*; D008666:Metalloendopeptidases / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D011266:Pregnancy-Associated Plasma Protein-A; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D017077:Culture Media, Conditioned; D018974:Insulin-Like Growth Factor Binding Protein 4; D010281:Parathyroid Hormone; D012333:RNA, Messenger; D004958:Estradiol; D008666:Metalloendopeptidases; D011266:Pregnancy-Associated Plasma Protein-A