+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Fluid shear stress-induced cyclooxygenase-2 expression is mediated by C/EBP beta, cAMP-response element-binding protein, and AP-1 in osteoblastic MC3T3-E1 cells



Fluid shear stress-induced cyclooxygenase-2 expression is mediated by C/EBP beta, cAMP-response element-binding protein, and AP-1 in osteoblastic MC3T3-E1 cells



Journal of Biological Chemistry 276(10): 7048-7054



Mechanical loading is crucial for maintenance of bone integrity and architecture, and prostaglandins are an important mediator of mechanosensing. Cyclooxygenase-2 (COX-2), an inducible isoform of prostaglandin G/H synthase, is induced by mechanical loading-derived fluid shear stress in bone-forming cells such as osteoblasts and osteocytes. In this study, we investigated transcription factor and transcriptional regulatory elements responsible for the shear stress-induced COX-2 expression in osteoblastic MC3T3-E1 cells. When the cells were transfected with luciferase-reporter plasmids including the 5'-flanking region of the murine cox-2 gene, the fluid shear stress increased the luciferase activities, consistent with the induction of COX-2 mRNA and protein expression. Deletion analysis of the promoter region revealed that the shear stress-induced luciferase responses were regulated by two regions, -172 to -100 base pair (bp) and -79 to -46 bp, of the cox-2 promoter, in which putative cis-elements of C/EBP beta, AP-1, cAMP-response element-binding protein (CREB), and E box are included. Mutation of sites of C/EBP beta, AP-1, and/or cAMP-response element decreased the shear stress-induced luciferase activities, whereas mutation of the E box did not affect the responses. In an electrophoretic mobility shift assay, shear stress enhanced nuclear extract binding to double-stranded oligonucleotide probes containing C/EBP beta and AP-1-binding motifs, and the bands of the complexes were supershifted by the addition of antibody specific for each regulator. Although the binding activity of CREB toward its probe was unaffected by shear stress, the phosphorylation of CREB was enhanced by the stress. These data suggest that C/EBP beta, AP-1, and CREB play crucial roles in the shear stress-induced cox-2 expression in osteoblasts.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 046105390

Download citation: RISBibTeXText

PMID: 11092885

DOI: 10.1074/jbc.m008070200


Related references

Fluid shear stress-induced cyclooxygenase-2 expression is mediated by C/EBP b, a cAMP-response element-binding protein, and AP-1 in osteoblastic MC3T3-E1 cells. The Journal of Biological Chemistry 276(10): 48-54, 2001

Morphological changes in osteoblastic cells (MC3T3-E1) due to fluid shear stress: cellular damage by prolonged application of fluid shear stress. Tohoku Journal of Experimental Medicine 191(3): 127-137, 2000

Shear stress-induced Ca(2+) elevation is mediated by autocrine-acting glutamate in osteoblastic MC3T3-E1 cells. Journal of Pharmacological Sciences 127(3): 311-318, 2016

Stimulation of amphiregulin expression in osteoblastic cells by parathyroid hormone requires the protein kinase A and cAMP response element-binding protein signaling pathway. Journal of Cellular Biochemistry 96(3): 632-640, 2005

Shear stress-induced C-type natriuretic peptide expression in HUVEC is mediated via shear stress-responsive element, different from cAMP induced up-regulation. Blood 90(10 SUPPL 1 PART 2): 79B, Nov 15, 1997

Impaired cAMP-mediated gene expression and decreased cAMP response element binding protein in senescent cells. American Journal of Physiology 271(1 Pt 1): C362-C371, 1996

Human DNA Polymerase-beta Promoter: Phorbol Ester Activation Is Mediated through the cAMP Response Element and cAMP-Response-Element-Binding Protein. Journal of Biomedical Science 4(6): 279-288, 2002

Neither the microfilament nor the microtubule cytoskeleton is required for fluid shear stress induced increases in cyclooxygenase-2 and prostaglandin release in MC3T3-E1 cells. Journal of Bone & Mineral Research 17(Suppl 1): S242, 2002

cAMP-dependent protein kinase type I regulates ethanol-induced cAMP response element-mediated gene expression via activation of CREB-binding protein and inhibition of MAPK. Journal of Biological Chemistry 279(41): 43321-9, 2004

Calcium/calmodulin-dependent kinase IV controls glucose-induced Irs2 expression in mouse beta cells via activation of cAMP response element-binding protein. Diabetologia 54(5): 1109-1120, 2011

Cytokine-mediated down-regulation of the transcription factor cAMP-response element-binding protein in pancreatic beta-cells. Journal of Biological Chemistry 278(25): 23055-23065, 2003

Parathyroid hormone induces c-fos promoter activity in osteoblastic cells through phosphorylated cAMP response element (CRE)-binding protein binding to the major CRE. Journal of Biological Chemistry 271(41): 25715-25721, 1996

Glucose-dependent insulinotropic polypeptide-mediated up-regulation of beta-cell antiapoptotic Bcl-2 gene expression is coordinated by cyclic AMP (cAMP) response element binding protein (CREB) and cAMP-responsive CREB coactivator 2. Molecular and Cellular Biology 28(5): 1644-1656, 2007

miRNA expression profile during fluid shear stress-induced osteogenic differentiation in MC3T3-E1 cells. Chinese Medical Journal 126(8): 1544-1550, 2014

cAMP response element-binding protein 1 is required for hydroxyurea-mediated induction of γ-globin expression in K562 cells. Clinical and Experimental Pharmacology and Physiology 39(6): 510-517, 2013