Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1990-9-13
pubmed:abstractText
The metabolism of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] by a human osteoblastic sarcoma cell line, U-2 OS, and by primary cultures of human bone-derived cells was examined at physiologic (5 x 10(-11) M) and pharmacologic (3.5 x 10(-7) M) substrate concentrations. For metabolite identification purposes, cells nearing confluency were incubated for 18 h with 3.5 x 10(-7) M 1,25-(OH)2D3 in serum-free medium. The putative vitamin D metabolites produced during this incubation were isolated from a total lipid extract of cells and medium. Identification of the metabolites was achieved by comigration with authentic standards on three high-performance liquid chromatography systems, UV spectral analysis, mass spectrometry, and chemical modification by sodium borohydride and sodium metaperiodate. The identified metabolites produced from 1,25-(OH)2D3 by the human osteosarcoma cells include 1,24,25-trihydroxyvitamin D3; 24-oxo-1,25-dihydroxyvitamin D3; 24-oxo-1,23,25-trihydroxyvitamin D3; and 24,25,26,27-tetranor-1,23-dihydroxyvitamin D3. Evidence is presented that (1) 1,25-(OH)2D3 metabolism occurs constitutively in U-2 OS osteosarcoma cells at a physiologic substrate concentration (5 x 11(-11) M), (2) the pathway can be further induced by pharmacologic 1,25-(OH)2D3 concentrations (10(-7) M), and (3) this pathway is present in primary cultures of normal human bone-derived cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0884-0431
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
597-608
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
1,25-Dihydroxyvitamin D3 metabolism in a human osteosarcoma cell line and human bone cells.
pubmed:affiliation
Norwich Eaton Pharmaceuticals, Inc., NY.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't