Linked Life Data

18050312

Source:http://linkedlifedata.com/resource/pubmed/id/18050312

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2008-3-12
pubmed:abstractText
A previous hypothesis stated that during osteoarthritis (OA) increased insulin-like growth factor (IGF) binding proteins (IGFBPs) sequester IGFs and limit their access to the cell. The objective of this article was to test this by: (1) quantifying IGF and IGFBP-3 as well as their ratios in human OA cartilages, and (2) measuring the metabolic responses of diseased cartilage to IGF-I and its IGFBP-insensitive analogs. Knee or hip OA cartilages were staged for OA by histology. Cartilage slices were either extracted for assays of IGF proteins, or maintained intact as organ cultures. Proteoglycan (PG) metabolism +/- IGFs was measured by use of the (35)S-sulfate precursor. IGFBP-3 (ng/mg protein) was weakly correlated with OA score by regression analysis (R(2) = 0.122; p = 0.040; n = 35). IGF-I (ng/mg protein) was constant across all OA groups (ANOVA; p = .428, n = 18) and the IGF-I/IGFBP-3 ratios were > 1 in most samples. All OA cartilages responded to hrIGF-I by increasing PG synthesis [average 2.29-fold +/- 0.55 (+/-SD) at saturation, n = 12] irrespective of OA score. The des (1-3) IGF-I analog (which lacks the three N-terminal amino acids) had similar maximal effects (average 2.23-fold stimulation +/- 0.71, n = 10), but it was more effective in two out of three samples at suboptimal doses. The effect of hrIGF-I, des (1-3) IGF-I, or the B-chain analog on degradation was minimal. In summary, catabolism was insensitive to IGF-I, and this was probably not due to IGFBPs. By contrast, IGF-I exerted a robust stimulation of anabolism at sufficiently high doses, even though IGFBPs could tone down the ligand effect at low doses.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1554-527X
pubmed:author
pubmed:copyrightInfo
(c) 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.
pubmed:issnType
Electronic
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
465-74
pubmed:dateRevised
2010-12-3
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
The quantitative and functional relation between insulin-like growth factor-I (IGF) and IGF-binding proteins during human osteoarthritis.
pubmed:affiliation
Harvard Medical School and Massachusetts General Hospital, Orthopaedics, Jackson 1223, 55 Fruit Street, Boston, Massachusetts 02114, USA. tmorales@partners.org
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural