Laminin decreases PRL and IGFBP‐1 expression during in vitro decidualization of human endometrial stromal cells

Abstract

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.

Autocrine/paracrine regulation of human endometrial stromal remodeling by laminin and type IV collagen

“…ESCs were detached from tissue culture dishes using 3 mM EDTA in PBS, and stained according to the following procedure. Cells (3x10 5 ) were incubated with an excess of one of the primary antibodies for 20 min at 4˚C, and then washed twice with washing buffer (PBS containing 2% FCS and 0.1% NaN 3 ). Then, the cells were reacted with FITC-conjugated goat anti-mouse IgG (H+L) (Dako) as a secondary antibody for 20 min at 4˚C, and washed twice.…”

“…Laminin and type IV collagen (COL-4) are well-known major components of epithelial basement membranes in the human body, and have been reported to localize in the basement membrane structure of human endometrial epithelium (1,2). Several studies have shown that these ECM components are produced at a high level in human deciduas (3,4), while laminin was reported to inhibit endometrial stromal decidualization (5,6). These ECM components were also reported to regulate trophoblast proliferation and differentiation during pregnancy (7)(8)(9)(10).…”

Adiponectin limits differentiation and trophoblast invasion in human endometrial cells

“…Decidualization occurs in response to the ovarian hormones, 17β-estradiol (E2) and progesterone (P4). It is accompanied by the secretion of prolactin and insulinlike growth factor-binding protein-1 (IGFBP-1), and the expression of the gap junction connexin-43 (CX-43) in human ESCs (Brar et al 1995, Yu et al 2011. Decidual ECM remodeling events have also been observed.…”

Remodeling of the human endometrial epithelium is regulated by laminin and type IV collagen

“…Several studies have shown that both these ECM components are highly expressed in human endometrial stromal cells and deciduas (3)(4)(5). Laminin has been reported to inhibit endometrial stromal differentiation (6,7), while both laminin and COL-4 have been found to regulate trophoblast proliferation and differentiation during pregnancy (8)(9)(10)(11). Furthermore, abnormal expression of these ECM components in the endometrium was reported in a patient with unexplained infertility (1).…”