Inductive effects of dexamethasone on the mineralization and the osteoblastic gene expressions in mature osteoblast-like ROS17/2.8 cells

We examined the effects of dexamethasone (Dex), a synthetic glucocorticoid, on the formation of mineralized bone nodules and the gene expressions of the late osteoblastic markers, bone sialoprotein (BSP), osteocalcin (OC), and osteopontin (OPN) in mature osteoblast ROS17/2.8 cells. Treatment of ROS1...

Full description

Saved in:
Bibliographic Details
Published in:Biochemical and biophysical research communications 2007-10, Vol.362 (2), p.368-373
Main Authors: Mikami, Yoshikazu, Omoteyama, Kazuki, Kato, Shigeyuki, Takagi, Minoru
Format: Article
Language:English
Subjects:
Alkaline Phosphatase - metabolism
Animals
Anthraquinones - chemistry
Blotting, Western
Calcification, Physiologic - drug effects
Calcium - metabolism
Cell Differentiation - drug effects
Cell Differentiation - genetics
Cell Line, Tumor
Core Binding Factor Alpha 1 Subunit - genetics
Core Binding Factor Alpha 1 Subunit - metabolism
Dexamethasone
Dexamethasone - pharmacology
Dose-Response Relationship, Drug
Gene Expression - drug effects
Glucocorticoids - pharmacology
Histocytochemistry
Integrin-Binding Sialoprotein
Mineralization
Osteoblasts - drug effects
Osteoblasts - metabolism
Osteocalcin - genetics
Osteocalcin - metabolism
Osteopontin - genetics
Osteopontin - metabolism
Reverse Transcriptase Polymerase Chain Reaction
RNA, Messenger - genetics
RNA, Messenger - metabolism
RNA, Small Interfering - genetics
ROS17/2.8
Runx2
Sialoglycoproteins - genetics
Sialoglycoproteins - metabolism
Time Factors
Transfection
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We examined the effects of dexamethasone (Dex), a synthetic glucocorticoid, on the formation of mineralized bone nodules and the gene expressions of the late osteoblastic markers, bone sialoprotein (BSP), osteocalcin (OC), and osteopontin (OPN) in mature osteoblast ROS17/2.8 cells. Treatment of ROS17/2.8 cells with Dex resulted in the induction of mineralization accompanied with increasing BSP and OC expressions. Previous reports have demonstrated that BSP and OC expressions are regulated by Runx2. Then, we hypothesized that Dex might promote osteoblastic differentiation and mineralization on ROS17/2.8 by Runx2. In this study, no effect was observed in mRNA and protein expression of Runx2. However, the transcriptional activity of Runx2 was enhanced by Dex treatment. Furthermore, the Dex-induced BSP and OC expressions decreased after the transfection of Runx2 small-interfering RNAs (siRNAs). These results suggested that the enhancement of Runx2 transcriptional activity by Dex treatment may be followed by the activation of osteoblast marker genes, such as BSP and OC to thereby produce a bone-specific matrix that subsequently becomes mineralized.
ISSN:0006-291X
1090-2104
DOI:10.1016/j.bbrc.2007.07.192