Multilevel regulation of steroid synthesis and metabolism in the bovine placenta

Abstract

SUMMARYSteroid hormones play critical roles in almost all physiological processes in male and female reproduction. In a normal pregnancy, the concentrations of steroid hormones in maternal and foetal blood vary with gestation in response to changing needs. The placenta plays a central role in producing the appropriate steroids to support the pregnancy by coordinating its own steroidogenic activity with that of the corpus luteum and responding to foetal signals. Although much is known about the steroidogenic potential of the bovine placenta, far less is known about how the placenta integrates the synthesis of steroids with their subsequent metabolism and clearance to achieve appropriate local and peripheral concentrations of steroids in maternal and foetal blood at each stage of gestation. This review focuses on the current knowledge of the temporal and spatial regulation and compartmentalization of the biochemical pathways by which potent steroid hormones are synthesized and metabolized in the bovine placenta. The aim is to increase our understanding of how the balance of synthesis and metabolism determines placental steroid output as it changes with development and differentiation, and how this is regulated in response to the variations in the foetal signals and luteal secretory activity. The review highlights knowledge gaps and suggests that mathematical modelling can help understand the effect of different levels of regulation on the steroidogenic output of an organ, such as the bovine placenta.

The influence of progesterone and prostaglandin F2α on decorin and the adhesion of caruncular epithelial cells of bovine placenta at early‐mid pregnancy—Part II

“…The present results indicate that the effect of P 4 on proliferation of bovine maternal epithelial cells is dependent on the gestation period. Cows in the 2nd month have a slightly higher concentration of progesterone in the blood compared with cows in the 4th month of pregnancy (Nguyen et al., 2012), which may be a result of its higher requirement in the first trimester of pregnancy. In fact, low P 4 levels during the first trimester of pregnancy increase the risk of miscarriage in humans.…”

Placenta specific gene targeting to study histone lysine demethylase and androgen signaling in ruminant placenta

“…This is surprising considering maternal serum level of testosterone increases during normal pregnancy (Figure 3 ). Transcripts of HSD3b, CYP11A1, and CYP17 are all present in ruminant placentomes ( Vanselow et al., 2004 ) and synthesis of androgens are localized to cotyledonary trophoblast cells ( Nguyen et al., 2012 ). In cow and sheep placentomes, AR is present in trophoblast cells, cotyledonary stromal cells, and caruncular epithelial and stromal cells ( Khatri et al., 2013 ; Cleys et al., 2015 ).…”

Neurohormones and temperament interact during infant development

“…The placenta plays an important role in synthesizing maternal hormones for the developing embryo to use during gestation [77,78], and can serve as a portal. Ultimately, only certain maternal hormones are permitted to cross the placental barrier, affecting subsequent fetal development [45].…”