EurekaMag.com logo
+ Site Statistics
References:
53,869,633
Abstracts:
29,686,251
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

RANKL/OPG ratio and DKK-1 expression in primary osteoblastic cultures from osteoarthritic and osteoporotic subjects



RANKL/OPG ratio and DKK-1 expression in primary osteoblastic cultures from osteoarthritic and osteoporotic subjects



Journal of Rheumatology 40(5): 684-694



To evaluate the expression of Dickkopf-1 protein factor (DKK-1), DKK-2, and β-catenin, components of the Wnt pathway, in human osteoarthritic (OA) and osteoporotic (OP) osteoblasts and to correlate it to cell metabolic activity, proliferation, and receptor activator of nuclear factor-κB ligand/osteoprotegerin (RANKL/OPG) expression. Primary human osteoblast cultures were obtained from healthy, OA, and OP donors. In each cell population we evaluated DKK-1, DKK-2, nonphosphorylated β-catenin and RANKL/OPG expression, osteocalcin and alkaline phosphatase (ALP) synthesis, and cell proliferation, both in basal condition and after vitamin D3 stimulation. DKK-1 and DKK-2 showed opposite patterns of expression in OA and OP osteoblasts. The RANKL/OPG ratio was significantly higher in the OP group because of a greater expression of RANKL, whereas it was significantly lower in the OA group because of a higher expression of OPG. Treatment with vitamin D3 increased the RANKL/OPG ratio and DKK-2 expression and reduced DKK-1 expression in each cell population, but did not affect β-catenin levels. Both osteocalcin and ALP production and cell proliferation were enhanced in OA cells and reduced in the OP ones. These data confirm that OA and OP are characterized by opposite bone changes, consisting of reduced bone remodeling processes with increased osteoblast activity in OA, and enhanced bone resorptive activity with reduction of osteoblast metabolism in OP, and suggest that the Wnt pathway is involved in the pathogenesis of both diseases.

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

Accession: 055333210

Download citation: RISBibTeXText

PMID: 23457386

DOI: 10.3899/jrheum.120845



Related references

RANKL/OPG in primary cultures of osteoblasts from post-menopausal women. Differences between osteoporotic hip fractures and osteoarthritis. Journal of Steroid Biochemistry and Molecular Biology 113(1-2): 46-51, 2009

Effect of IL-1beta, PGE(2), and TGF-beta1 on the expression of OPG and RANKL in normal and osteoporotic primary human osteoblasts. Journal of Cellular Biochemistry 110(2): 304-310, 2010

Coptisine inhibits RANKL-induced NF-κB phosphorylation in osteoclast precursors and suppresses function through the regulation of RANKL and OPG gene expression in osteoblastic cells. Journal of Natural Medicines 66(1): 8-16, 2012

Alterations in osteocalcin expression and secretion in osteoblastic cells in primary culture from patients with osteoporotic hip fracture. Journal of Bone & Mineral Research 15(Suppl 1): S333, September, 2000

Neridronate and human osteoblasts in normal, osteoporotic and osteoarthritic subjects. Clinical Rheumatology 24(5): 527-534, 2005

The expression of RANKL and OPG in the various grades of osteoarthritic cartilage. Rheumatology International 32(2): 535-540, 2012

IL-1 regulation of osteoblastic differentiation in murine bone marrow and primary osteoblastic cultures. Journal of Bone & Mineral Research 15(Suppl 1): S508, September, 2000

Circulating RANKL is inversely related to RANKL mRNA levels in bone in osteoarthritic males. Arthritis Research & Therapy 10(1): R2-R2, 2008

Aromatase expression in osteoarthritic and osteoporotic bone. Arthritis and Rheumatism 58(6): 1696-1700, 2008

Osteoblastic cells from rat long bone. II: Adhesion to substrata and integrin expression in primary and propagated cultures. Cell Biology International 21(1): 7-16, 1997

Osteogenic protein-1-mediated insulin-like growth factor gene expression in primary cultures of rat osteoblastic cells. Endocrinology 137(5): 1921-1931, 1996

Effects of polyethylene and alpha-alumina particles on IL-6 expression and secretion in primary cultures of human osteoblastic cells. Biomaterials 23(3): 901-908, 2002

Effect of bisphosphonates on the expression of OPG and RANKL in mouse calvarial osteoblastic cells. Journal of Bone & Mineral Research 16(Suppl 1): S364, September, 2001

Thyroid hormone, vitamin D and retinoid receptor expression and signalling in primary cultures of rat osteoblastic and immortalised osteosarcoma cells. Journal of Endocrinology 154(1): 63-74, 1997

Involvement of ERK and p38 MAPK pathways on Interleukin-33-induced RANKL expression in osteoblastic cells. Cell Biology International 38(5): 655-662, 2015