Brar A K, Frank G R, Richards R G, Meyer A J, Kessler C A, Cedars M I, Klein D J, Handwerger S
Division of Endocrinology, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039.
J Cell Physiol. 1995 Apr;163(1):30-7. doi: 10.1002/jcp.1041630105.
The expression of laminin, a major constituent of endometrial cell basement membranes, is increased during differentiation of human endometrial stromal cells (decidualization). To determine whether laminin plays a role in decidualization, we studied the effects of laminin substrate on the synthesis and release of prolactin (PRL) and insulin-like growth factor binding protein-1 (IGFBP-1), two major secretory proteins of decidualized stromal cells. Endometrial stromal cells were plated on laminin as well as several other extracellular matrix (ECM) proteins (types 1 and IV collagen or fibronectin) and on plastic, and cultured in media containing medroxyprogesterone acetate (MPA) and estradiol. Cells cultured on plastic or ECM proteins displayed similar morphological changes indicative of decidualization. However, the release of PRL and IGFBP-1 from cells cultured on plastic and ECM proteins (types 1 and IV collagen and fibronection) was approximately 2.1-fold and 2.8-fold greater respectively, than from cells cultured on laminin. The decrease in PRL and IGFBP-1 expression in cells cultured on laminin was not due to differences in initial cell attachment efficiency or final DNA content. In addition, laminin had no effect on the content of laminin protein or fibronectin mRNA levels, indicating that the effects of laminin on PRL and IGFBP-1 were specific. PGE2 stimulated the release of PRL and IGFBP-1 from cells cultured on laminin to levels comparable to those from cells cultured on plastic or other ECM proteins. This indicates that the decrease in PRL and IGFBP-1 release by laminin was not due to a generalized unresponsiveness. In contrast to the effects of laminin during decidualization, PRL expression was not altered by laminin in terminally differentiated decidual cells isolated at term. Our results support a role for laminin in selectively regulating PRL and IGFBP-1 gene expression during in vitro decidualization of human endometrial stromal cells.
层粘连蛋白是子宫内膜细胞基底膜的主要成分，在人子宫内膜基质细胞分化（蜕膜化）过程中表达增加。为了确定层粘连蛋白在蜕膜化中是否发挥作用，我们研究了层粘连蛋白底物对催乳素（PRL）和胰岛素样生长因子结合蛋白-1（IGFBP-1）合成与释放的影响，这两种蛋白是蜕膜化基质细胞的两种主要分泌蛋白。将子宫内膜基质细胞接种于层粘连蛋白以及其他几种细胞外基质（ECM）蛋白（I型和IV型胶原或纤连蛋白）和塑料上，并在含有醋酸甲羟孕酮（MPA）和雌二醇的培养基中培养。接种于塑料或ECM蛋白上的细胞显示出类似的形态变化，表明发生了蜕膜化。然而，接种于塑料和ECM蛋白（I型和IV型胶原以及纤连蛋白）上的细胞释放的PRL和IGFBP-1分别比接种于层粘连蛋白上的细胞高出约2.1倍和2.8倍。接种于层粘连蛋白上的细胞中PRL和IGFBP-1表达的降低并非由于初始细胞附着效率或最终DNA含量的差异。此外，层粘连蛋白对层粘连蛋白蛋白含量或纤连蛋白mRNA水平没有影响，表明层粘连蛋白对PRL和IGFBP-1的作用是特异性的。前列腺素E2（PGE2）刺激接种于层粘连蛋白上的细胞释放PRL和IGFBP-1，使其水平与接种于塑料或其他ECM蛋白上的细胞相当。这表明层粘连蛋白导致PRL和IGFBP-1释放减少并非由于普遍的无反应性。与层粘连蛋白在蜕膜化过程中的作用相反，足月分离的终末分化蜕膜细胞中，层粘连蛋白对PRL表达没有影响。我们的结果支持层粘连蛋白在体外人子宫内膜基质细胞蜕膜化过程中选择性调节PRL和IGFBP-1基因表达的作用。
