Linked Life Data

11241663

Source:http://linkedlifedata.com/resource/pubmed/id/11241663

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2001-3-12
pubmed:abstractText
Insulin-like growth factor (IGF)-I is an important regulator of bone metabolism. Clinical observations suggest that different anatomic sites within the adult skeleton respond differently to hormonal and therapeutic treatment, and recent studies on bone marrow stromal cells in culture show that there are skeletal site-dependent differences in the gene expression of IGF-I. The actions of IGF-I and -II on bone cells are known to be modulated by the IGF binding proteins (IGFBP)-1 through -6 and the Type I and Type II IGF receptors. Therefore, we compared the expression of IGFBP-1 through -6 in adult female rat bone marrow stromal cell cultures derived from two separate skeletal sites: vertebrae and femurs. The cultures were maintained simultaneously under conditions that support osteoblast differentiation from osteoprogenitors present in the femoral and vertebral marrow cell populations. We also addressed whether IGFBP messenger RNA levels are regulated by thyroid hormone (T(3)) and dexamethasone (dex) treatment in femoral vs. vertebral marrow stromal cells in vitro, since steroid hormones play an important role in skeletal function. Northern blot analyses revealed that there are distinct skeletal site differences in the gene expression of IGFBPs. The vertebral marrow cultures express IGFBP-2 through -6 mRNAs, with IGFBP-2, IGFBP-4, and IGFBP-6 mRNAs predominating. The femoral marrow stromal cell cultures express only IGFBP-4 and IGFBP-6. Importantly, vertebral marrow cultures have much higher IGFBP mRNA steady-state levels than femoral cultures for all the detected IGFBP transcripts. IGFBP-1 is not detected in either femoral or vertebral cultures. In addition to a skeletal site difference, we show that T(3) and dex regulate the expression of specific IGFBP mRNAs. T(3) treatment also upregulates IGF-I protein secretion by vertebral marrow stromal cell cultures. Interestingly, the type I receptor for IGF-I was expressed equivalently in cultures from the two skeletal sites. These findings have important implications for the anatomical site specificities of hormonal responses that are noted in the skeleton.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0730-2312
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
81
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
229-40
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed-meshheading:11241663-Animals, pubmed-meshheading:11241663-Blotting, Northern, pubmed-meshheading:11241663-Bone Marrow Cells, pubmed-meshheading:11241663-Culture Media, Serum-Free, pubmed-meshheading:11241663-Dexamethasone, pubmed-meshheading:11241663-Dose-Response Relationship, Drug, pubmed-meshheading:11241663-Female, pubmed-meshheading:11241663-Femur, pubmed-meshheading:11241663-Gene Expression Regulation, pubmed-meshheading:11241663-Insulin-Like Growth Factor Binding Proteins, pubmed-meshheading:11241663-Insulin-Like Growth Factor I, pubmed-meshheading:11241663-RNA, Messenger, pubmed-meshheading:11241663-Rats, pubmed-meshheading:11241663-Rats, Sprague-Dawley, pubmed-meshheading:11241663-Spine, pubmed-meshheading:11241663-Time Factors, pubmed-meshheading:11241663-Triiodothyronine
pubmed:year
2001
pubmed:articleTitle
Insulin-like growth factor binding proteins in femoral and vertebral bone marrow stromal cells: expression and regulation by thyroid hormone and dexamethasone.
pubmed:affiliation
Department of Orthopedics and Physical Rehabilitation, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
pubmed:publicationType
Journal Article