Poster The Annual Scientific Meeting of the Endocrine Society of Australia and the Society for Reproductive Biology 2013

TGFβ1 regulates the production of osteogenic factors in human endometrial fibroblasts (#216)

Jonathan McGuane 1 , Jamie Zhang 1 , David Sharkey 1 , Zhao Wang 1 , Louise Hull 1
  1. Research Centre for Reproductive Health, University of Adelaide, Adelaide, South Australia, Australia

TGFβ1 is a pleiotropic cytokine that stimulates extracellular matrix production and bone remodelling,1 and is strongly implicated in the pathogenesis of endometriosis.2  Microarray analysis of endometriosis lesions demonstrates that several osteogenic factors are up-regulated in ectopic vs eutopic tissues. We hypothesised that osteogenic factors are expressed by human endometrial fibroblasts (HEF) and regulated in response to TGFβ1.

Primary HEF were isolated from endometrial tissue of women undergoing laparoscopy for endometriosis symptoms (n=10). Immortalised and primary HEF were treated with 0.05-50ng/mL TGFβ1 or vehicle for 6-24hr and media collected 24hr later. Periostin, osteopontin, and osteoprotegerin concentration was assessed by ELISA or Luminex assay. For gene expression studies, primary HEF were treated with 0.5ng/mL TGFβ1 or vehicle for 4.5hr and total RNA extracted. qRT-PCR was performed for periostin, osteopontin, osteoprotegerin, TGFβ1, Runx2, dermatopontin, osteonectin, matrix Gla Protein (MGP), versican, fibromodulin, and insulin-like growth factor binding protein 5 (IGFBP5).

TGFβ1 treatment of immortalised HEF had no effect on osteopontin but significantly (P<0.05, 1-way ANOVA) decreased periostin concentration. In primary HEF, TGFβ1 dramatically decreased periostin concentration and modestly increased osteopontin in time and/or dose dependent fashion (P<0.05, 2-way ANOVA). Osteoprotegerin production from primary HEF was also decreased in response to TGFβ1 (P<0.001, t-test). At the mRNA level, TGFβ1 treatment resulted in osteoprotegerin and IGFBP5 down-regulation, and TGFβ1 and Runx2 up-regulation (P<0.05, t-test), whereas periostin, osteopontin, dermatopontin, osteonectin, MGP, versican, and fibromodulin were not affected.

In conclusion, TGFβ1 regulates osteogenic factor production in human endometrial cells. Given that TGFβ1 induces an osteoclast-recruiting osteogenic factor profile in human osteoblasts (e.g., ↓periostin and ↓osteoprotegerin),3  and that osteoclasts and macrophages share a common cellular lineage, we speculate that TGFβ1 regulation of osteogenic factors may influence the recruitment of macrophages to endometriotic tissues, where they play an essential role in lesion development.4

  1. Bonewald et al., J Cell Biochem 1994;55(3)350-7
  2. Hull et al., Am J Pathol 2008;173(3)700-15
  3. Enhert et al., PLoS ONE 2010;5(11)1-9
  4. Bacci et al., Am J Pathol 2009;175(2)547-56