Activin A Stimulates Interleukin 8 and Vascular Endothelial Growth Factor Release From Cultured Human Endometrial Stromal Cells: Possible Implications for the Pathogenesis of Endometriosis

Background: Activin A is an endometrial secretory product involved in inflammation and angiogenesis. The present study aimed to evaluate the effect of activin A and its antagonist follistatin on interleukin (IL)-6, IL-8, and vascular endothelial growth factor (VEGF) expression and release from cultured human endometrial stromal cells (HESCs) from women with and without endometriosis. Methods: The HESCs were collected from women with endometriosis (n = 6) and controls (n = 6). Primary cultures were treated with activin A at different doses or activin A plus follistatin. The IL-6, IL-8, and VEGF messenger RNA expression was evaluated by real-time polymerase chain reaction and protein release was evaluated by enzyme-linked immunosorbent assay. Results: Unstimulated HESC from women with endometriosis secreted more IL-6 and IL-8 than controls. The addition of activin A increased IL-8 and VEGF secretion in HESC from controls and decreased IL-6 and IL-8 secretion in HESC from women with endometriosis. These effects were counteracted by follistatin. Conclusion: Activin A regulates the expression and secretion of IL-8 and VEGF in cultured HESC, and this mechanism appears to be disrupted in eutopic endometrial cells from women affected by endometriosis.