Estrogen and progesterone regulate thrombospondin-1 expression in cultured endometrial stromal cells

Objective To evaluate the effects of estrogen(E2) and progesterone(P4) on the expression of thromobospondin-1(TSP-1) in cultured human endometrial stromal cells(ESCs).Methods ESCs were isolated,cultured in Peking Union medical college hospital between December,2008 and October 2009.ESCs were treated with different concentrations of E2 and P4 for designed hours,then total RNA and protein were extracted for analysis of TSP-1 expression with Northern blot and Western blot respectively.Results E2 inhbited TSP-1 expression in ESCs.Compared with untreated cells,TSP-1 mRNA and protein levels in ESCs treated with E2(10nmol/L) were reduced by(47.6±6.5)% (P0.05) and(49.0±8.6)%(P0.05) respectively.Progesterone at a high concentration(10μmol/L) induced TSP-1 expression.TSP-1 mRNA and protein in ESCs treated with P4(10μmol/L) was as(2.1±0.4) times(P0.05)and(2.3±0.6) times(P0.05) higher than those in untreated cells(P0.05).P4 at a low concentration(10nmol/L)enhanced the inhibitory effect of E2 on TSP-1 protein but not mRNA expression.Conclusion The findings that estrogen and progesterone differentially regulate the expression of TSP-1 in ESCs not only provide evidence for the estrogen dependence of endometriosis,but also partly explain the mechanisms by which progestins exert their therapeutic activities in endometriosis.