Linked Life Data

8053399

Source:http://linkedlifedata.com/resource/pubmed/id/8053399

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1994-9-2
pubmed:abstractText
To determine how progestins increase bone formation in vivo, the effects of the synthetic progestin norethindrone (NET), on aspects of bone formation in vitro were determined. NET at picomolar concentrations in vitro stimulated the proliferation of human TE85 osteosarcoma cells as assessed by the increase in [3H]thymidine incorporation into DNA and in cell number and also stimulated the release of osteocalcin in both the presence and absence of 10 nM 1,25-(OH)2D3. NET increased cellular alkaline phosphatase specific activity (an index of osteoblastic differentiation), but at much higher concentrations, that is, nanomolar. These findings suggest that low concentrations of NET act directly on human TE85 osteosarcoma cells to stimulate their proliferation, differentiation, and cell activity. Furthermore, mitogenic doses of NET stimulated bone collagen synthesis both in a chicken calvarial organ culture assay (assessed by the incorporation and hydroxylation of [3H]proline) and in a human TE85 osteosarcoma cell culture assay (determined by the incorporation of [3H]proline into collagenase-digestible proteins). In contrast, NET at 10(-6)-10(-12) M had no apparent effect on the rate of basal or PTH-stimulated release of 45Ca from prelabeled mouse calvariae in vitro. In summary, this study has demonstrated for the first time that picomolar NET acted directly on human TE85 osteosarcoma cells to increase (1) cell proliferation and differentiation, (2) osteoblastic activity (i.e., osteocalcin synthesis), and (3) bone collagen synthesis in vitro. The same doses of NET in vitro did not reduce the bone resorption rate under our assay conditions.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0884-0431
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
695-703
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Picomolar norethindrone in vitro stimulates the cell proliferation and activity of a human osteosarcoma cell line and increases bone collagen synthesis without an effect on bone resorption.
pubmed:affiliation
Department of Medicine, Loma Linda University, California.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.