17 beta-estradiol inhibits interleukin-6 production by bone marrow-derived stromal cells and osteoblasts in vitro: a potential mechanism for the antiosteoporotic effect of estrogens.
AUTOR(ES)
Girasole, G
RESUMO
The effect of 17 beta-estradiol on interleukin-6 (IL-6) synthesis was examined in murine bone marrow-derived stromal cell lines, normal human bone-derived cells, and nontransformed osteoblast cell lines from mice and rats. In all these cell types IL-6 production was stimulated as much as 10,000-fold in response to the combination of recombinant interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF alpha). Addition of 17 beta-estradiol in the cultures exerted a dose-dependent inhibition of IL-1-, TNF-, and IL-1 + TNF-induced production of bioassayable IL-6. Testosterone and progesterone (but not 17 alpha-estradiol) also inhibited IL-6, but their effective concentrations were two orders of magnitude higher than 17 beta-estradiol. 17 beta-estradiol also decreased the levels of the IL-6 mRNA. In addition, estradiol inhibited both TNF-induced IL-6 production and osteoclast development in primary bone cell cultures derived from neonatal murine calvaria. The TNF-stimulated osteoclast development was also suppressed by a neutralizing monoclonal anti-IL-6 antibody. This in vitro evidence suggests, for the first time, a mechanistic paradigm by which estrogens might exert at least part of their antiresorptive influence on the skeleton.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=442934Documentos Relacionados
- 17 beta-Estradiol inhibits expression of human interleukin-6 promoter-reporter constructs by a receptor-dependent mechanism.
- Direct effects of 17 beta-estradiol on trabecular bone in ovariectomized rats.
- Expression of interleukin-8 by lipopolysaccharide-stimulated bone marrow-derived mononuclear cells.
- Calmodulin-stimulated phosphorylation of 17 beta-estradiol receptor on tyrosine.
- Thymocyte resettes: Multicellular complexes of lymphocytes and bone marrow-derived stromal cells in mouse thymus