Endocrine Abstracts

The active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25D3) is a potent antiproliferative/immunomodulatory steroid hormone with many applications outside calcium homeostasis. This is particularly true in the placenta which can generate 1,25D3 locally via the enzyme 1alpha-hydroxylase (CYP27b) in both trophoblast and decidua. We have investigated the potential function of 1,25D3 across gestation using human tissue obtained after l...

Glucocorticoids (GCs) play a fundamental role in the endocrinology of pregnancy but excess GC in utero may lead to IUGR. Protection against fetal exposure to GCs is provided by the enzyme 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2) located in the placental trophoblast. By contrast, relatively little is known concerning the function of GC-activating 11beta-HSD1 which is expressed within maternal decidua. We have used human deciduas (n=32 first, n=10 second and n=...

During early development, the extravillous and villous placenta form by a process of proliferation and differentiation resulting in invasion of the uterine decidua and myometrium. The invasion of tissues during placentation is a model for the proliferative and invasive processes which occur during tumourogenesis. Pituitary tumor transforming gene (PTTG) interacts with a binding factor PBF, and PTTG expression correlates with tumor invasiveness in many neoplasms. We hypothesise...

Thyroid hormones are essential for optimum fetal neurodevelopment. In-utero nutrition is dependant on adequate placentation. Epidermal growth factor (EGF) and hepatocyte growth factor (HGF) have been demonstrated to affect proliferation of human trophoblast and may therefore play a role in adequate human placentation. Intrauterine growth restriction (a process associated with malplacentation) is associated with fetal hypothyroxinemia and enhanced thyroid receptor (TR) expressi...

Homeobox (HOX) genes encode proteins that are important in normal foetal development. Some of these genes such as HOXA10 also appear to be involved in haematopoiesis, tumour invasion and normal uterine function. HOXA10 is sensitively regulated by hormonal changes during the menstrual cycle. In addition, knockout mouse studies have suggested a role for HOXA10 in implantation but its precise mechanism of action remains unclear. To further investigate HOXA10 function in human rep...

Human securin, known also as pituitary tumor transforming gene (PTTG), has established oncogenic and cell regulatory functions. PTTG transforms cells in vitro, inhibits sister chromatid separation and regulates secretion of fibroblast growth factor-2 (FGF-2). FGF-2 is a key regulator of CNS development and PTTG/securin expression has previously been reported in murine fetal brain. We examined mRNA and protein expression of PTTG and FGF-2 in 35 first trimester (7-12 weeks) and ...