miR‑455 targets FABP4 to protect human endometrial stromal cells from cytotoxicity induced by hydrogen peroxide

Excessive endometrial PlGF- Rac1 signalling underlies endometrial cell stiffness linked to pre-eclampsia

Cell stiffness is regulated by dynamic interaction between ras-related C3 botulinum toxin substrate 1 (Rac1) and p21 protein-activated kinase 1 (PAK1) proteins, besides other biochemical and molecular regulators. In this study, we investigated how the Placental Growth Factor (PlGF) changes endometrial mechanics by modifying the actin cytoskeleton at the maternal interface. We explored the global effects of PlGF in endometrial stromal cells (EnSCs) using the concerted approach of proteomics, atomic force microscopy (AFM), and electrical impedance spectroscopy (EIS). Proteomic analysis shows PlGF upregulated RhoGTPases activating proteins and extracellular matrix organization-associated proteins in EnSCs. Rac1 and PAK1 transcript levels, activity, and actin polymerization were significantly increased with PlGF treatment. AFM further revealed an increase in cell stiffness with PlGF treatment. The additive effect of PlGF on actin polymerization was suppressed with siRNA-mediated inhibition of Rac1, PAK1, and WAVE2. Interestingly, the increase in cell stiffness by PlGF treatment was pharmacologically reversed with pravastatin, resulting in improved trophoblast cell invasion. Taken together, aberrant PlGF levels in the endometrium can contribute to an altered pre-pregnancy maternal microenvironment and offer a unifying explanation for the pathological changes observed in conditions such as pre-eclampsia (PE).

FABP4 mediates endoplasmic reticulum stress and autophagy to regulate endometrial epithelial cell function during early sheep gestation

Dynamic changes in the endometrium are crucial for establishing early pregnancy in ruminants. Blastocyst elongation and implantation require hormones and nutrients to be secreted from the maternal endometrium. The fatty acid-binding protein FABP4 is a widely expressed fatty acid transport protein that promotes cell proliferation, migration, and invasion and is involved in conceptus implantation. However, the mechanism underlying the functional regulation of endometrial epithelial cells (EECs) by FABP4 during ovine peri-implantation remains unclear. We simulated hormonal changes in vitro in sheep EECs (SEECs) during the peri-implantation period and found that it elevated FABP4 expression. FABP4 inhibition significantly reduced cell migration, endoplasmic reticulum stress, and autophagy, suggesting that FABP4 regulates endometrial function in sheep. Moreover, the FABP4 inhibitor BMS309403 counteracted hormone-mediated functional changes in SEECs, and an endoplasmic reticulum stress activator and autophagy inhibitor reversed the abnormal secretion of prostaglandins induced by FABP4 inhibition. These results suggest that FABP4 affects ovine endometrial function during early gestation by regulating endoplasmic reticulum stress and autophagy in SEECs.

Iron Therapeutics in Women's Health: Past, Present, and Future

Iron plays a unique physiological role in the maintenance of homeostasis and the pathological outcomes of the female reproductive tract. The dual nature of elemental iron has created an evolutionary need to tightly regulate its biological concentration. The female reproductive tract is particularly unique due to the constant cycle of endometrial growth and shedding, in addition to the potential need for iron transfer to a developing fetus. Here, iron regulation is explored in a number of physiologic states including the endometrial lining and placenta. While iron dysregulation is a common characteristic in many women's health pathologies there is currently a lack of targeted therapeutic options. Traditional iron therapies, including iron replacement and chelation, are common treatment options for gynecological diseases but pose long term negative health consequences; therefore, more targeted interventions directed towards iron regulation have been proposed. Recent findings show potential benefits in a therapeutic focus on ferritin-hepcidin regulation, modulation of reactive oxygen species (ROS), and iron mediated cell death (ferroptosis). These novel therapeutics are the direct result of previous research in iron's complex signaling pathway and show promise for improved therapy, diagnosis, and prognosis in women's health.