The association between progestins, nuclear receptors expression and inflammation in endometrial stromal cells from women with endometriosis

Endometriosis is an inflammatory disease and nuclear receptors play a crucial role in mediating the inflammatory response. In endometrial stromal cells (ESC), nuclear receptors expression can be influenced by the local environment. Progestins are first-line, on-label treatments of endometriosis that may have direct effects on endometriotic lesions through these nuclear receptors. Therefore, we investigated whether there was an association between nuclear receptors expression and the influence of progestins on inflammatory cytokines production in a preliminary, in vitro study with primary cultures. ESC from endometrial biopsies of six subjects with histologically confirmed endometriosis were treated for 6 h with medium alone or with TNF-α (10 or 100 ng/ml) in the presence of dienogest (DNG), medroxyprogesterone acetate (MPA) and norethisterone acetate (NETA) 10-5 M. The progestin-mediated change in IL6, IL8 and MCP-1 mRNA transcription was measured, as was the PRA, PRB, GR, AR and MCR protein expression. The change (medium versus TNF-α 10 ng/ml and medium versus TNF-α 100 ng/ml) in IL6 mRNA transcription was positively associated with the change in PRB, but not PRA with both DNG and NETA treatment. The change in IL8 mRNA was negatively associated with AR expression in the presence of NETA. The change in MCP-1 mRNA expression was positively associated with GR expression and negatively associated with MCR after MPA treatment. The associations between the change in cytokines mRNA expression and nuclear receptors protein expression in response to progestins activity may indirectly suggest different activities of these compounds at a local level worthy of further investigations.