Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-1-8
pubmed:abstractText
Interleukin-6 (IL-6) is a potent stimulator of bone resorption which has been demonstrated in a variety of in vivo and in vitro models. We investigated the regulation of IL-6 secretion in primary human osteoblastic cells (HOC) in vitro by cytokines known to play an important role in coupling bone formation to bone resorption. HOC were isolated from healthy adults who underwent selective orthopedic surgery and treated with cytokines released in the bone microenvironment during coupling i.e Interleukin-1beta (IL-1beta), Tumor Necrosis Factor alpha (TNFalpha), Transforming Growth Factor beta1 and 2 (TGFbeta 1 and 2) and Endothelin-1 (ET-1). Furthermore, we determined whether systemically-acting steroid hormones of gonadal and adrenal origin as well as glucocorticoids affect the local regulation of IL-6 secretion in primary HOC. To examine the effects of different steroid hormones on IL-6 production, HOC were exposed to estradiol (E2), dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA) and dexamethasone (Dexa) with and without a subsequent treatment of the HOC populations with cytokines. We observed that (1) IL-1beta and TNFalpha induced IL-6 in a dose and time-dependent fashion, (2) TGFbeta 1 and 2 enhanced basal and IL-1beta and TNFalpha induced IL-6 expression, (3) ET-1 elicited a dose-dependent stimulatory effect on IL-6 expression. (4) E2, DHT and DHEA alone and in combination with IL-1beta and TNFalpha elicited no reproducible dose-dependent effect on IL-6 production, whereas Dexa inhibited basal and IL-1beta and TNFalpha induced IL-6 expression dose dependently. In conclusion, IL-1beta, TNFalpha, TGFbeta 1 and 2 and ET-1 may participate in the regulation of bone resorption by stimulating IL-6 expression in HOC. Dexa inhibits the constitutive and cytokine stimulated IL-6 expression, whereas there is no in vitro evidence that sex steroids exert a major inhibitory effect on the osteoblastic secretion of IL-6 as demonstrated in a primary human bone cell model.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0947-7349
pubmed:author
pubmed:issnType
Print
pubmed:volume
106
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
324-33
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Regulation of interleukin-6 expression in human osteoblastic cells in vitro.
pubmed:affiliation
Ruprecht-Karls-University of Heidelberg, Department of Medicine, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't