title: 17-β-estradiol up-regulates apolipoprotein genes expression during osteoblast differentiation in vitro.
abstract: Apolipoproteins are of great physiological importance and are associated with different diseases. Many independent studies of patterns of gene expression during osteoblast differentiation have been described, and some apolipoproteins have been induced during this process. 17-β-estradiol (E2) may enhance osteoblast physiological function. However, no studies have indicated whether E2 can modulate the expression of apolipoproteins during osteoblast differentiation in vitro. The aim of the current study was to observe the regulation of apolipoprotein mRNA expression by E2 during this process. Primary osteoblasts were collected from the calvaria of newborn mice and were subjected to osteoblast differentiation in vitro with serial concentrations of E2. RNA was isolated on days 0, 5, and 25 of differentiation. Real-time PCR was performed to analyze the levels of apolipoprotein mRNA. Results showed that during osteoblast differentiation all of the apolipoprotein genes were up-regulated by E2 in a dose-dependent manner. Moreover, only ApoE was strongly induced during the mineralization of cultured osteoblasts. This result suggests that ApoE might be involved in osteoblast differentiation. The hypothesis is that E2 promotes osteoblast differentiation by up-regulating ApoE gene expression, though further study is needed to confirm this hypothesis.
authors.affiliation: Laboratory for Reproductive Immunology, Hospital & Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College.
authors.forename: Yuyan
authors.initials: Y
authors.lastname: Gui
authors.forename: Nan
authors.initials: N
authors.lastname: Chu
authors.forename: Xuemin
authors.initials: X
authors.lastname: Qiu
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Gober
authors.forename: Dajin
authors.initials: D
authors.lastname: Li
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
mesh_terms: D000818:Animals; D001053:Apolipoproteins / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics*; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D015854:Up-Regulation / Q000187:drug effects*
chemical_list: D001053:Apolipoproteins; D012333:RNA, Messenger; D004958:Estradiol