Enhanced Human Decidual Cell-Expressed FKBP51 May Promote Labor-Related Functional Progesterone Withdrawal.

Sustained plasma progesterone (P4) levels suggest initiation of human term labor by functional P4 withdrawal, reflecting reduced progesterone receptor (PR) and/or glucocorticoid receptor (GR) expression or activity. The steroid-induced immunophilin cochaperone FKBP51 inhibits PR- and GR-mediated transcription, suggesting a labor-initiating role. Gestational age-matched decidual sections were immunostained for FKBP51 and decidual cell (DC) and interstitial trophoblast (IT) markers, vimentin and cytokeratin, respectively.

Effects of tibolone and its metabolites on prolactin and insulin-like growth factor binding protein-1 expression in human endometrial stromal cells.

The effects of the postmenopausal replacement steroid tibolone and its 3α-, 3β-OH and Δ-4 tibolone metabolites were evaluated on progesterone receptor-mediated classic decidualization markers insulin-like growth factor binding protein-1 (IGFBP-1) and prolactin expression in human endometrial stromal cells (HESCs). Supernatants of conditioned medium or erxtracted RNA from experimental cell incubations of confluent HESCs were subjected to ELISAs, Western blot analysis and RT/PCR, and results were statisically assesed. Over 21 days, specific ELISAs observed linear increases in secreted IGFBP-1 and prolactin levels elicited by tibolone and its metabolites.

Toll-like receptor 4 expression in decidual cells and interstitial trophoblasts across human pregnancy.

Problem: Toll-like receptor-4 (TLR-4) protects against Gram-negative bacteria expressed lipopolysaccharide and 'danger signals' from injured or dying cells. Although decidual cells (DCs) and interstitial trophoblasts (ITs) are in close contact, TLR-4 has been studied extensively only in ITs.

Method Of Study: Formalin-fixed, paraffin-embedded serial sections of endometrium in follicular and luteal phases and deciduas from first and second trimester elective terminations and third trimester normal deliveries were immunostained for TLR-4, trophoblast-specific cytokeratin, and DC-specific vimentin.

Bidirectional interaction between unfolded-protein-response key protein HSPA5 and estrogen signaling in human endometrium.

The human endometrium is a dynamic tissue that undergoes cyclic changes under the influence of steroid hormones as well as numerous local paracrine and autocrine factors. Heat shock 70 kDa protein (HSPA5; also known as GRP78/BiP), a molecular chaperone within the endoplasmic reticulum, plays crucial roles in normal cellular processes as well as in stress conditions, in which it is a central regulator for the unfolded protein response (UPR). We hypothesized that HSPA5 expression level is variable throughout the menstrual cycle in human endometrium and that estrogen signaling cross-talks with UPR signaling by interacting with HSPA5.