Changes in human placental 5α-reductase isoenzyme expression with advancing gestation: effects of fetal sex and glucocorticoid exposure

2009 ◽  
Vol 21 (4) ◽  
pp. 599 ◽  
Author(s):  
Thi T. Vu ◽  
Jonathan J. Hirst ◽  
Michael Stark ◽  
Ian M. R. Wright ◽  
Hannah K. Palliser ◽  
...  

5α-Reduced steroids, including allopregnanolone, suppress neuronal activity and can have neuroprotective effects in the fetus. 5α-Reductases in the placenta may contribute precursors to brain allopregnanolone synthesis. Preterm birth and glucocorticoids, administered for fetal lung maturation or for maternal asthma, may influence reductase expression. The aims of the present study were to evaluate placental 5α-reductase isoform expression during late gestation and to examine fetal sex differences and the effects of glucocorticoid therapies on the expression of these enzymes. Expression of the two 5α-reductase isoenzymes was measured in placental samples, whereas cortisol concentrations were measured in cord blood, from two cohorts. The first cohort consisted of women who delivered preterm and received betamethasone treatment (n = 41); the second cohort consisted of women who delivered at term and were either healthy controls (n = 30) or asthmatics who had used glucocorticoids (n = 24). Placental expression of both isoenzymes increased with advancing gestation and there were marked sex differences in levels of 5α-reductase I (P < 0.05), but not of 5α-reductase II. The expression of both enzymes was positively correlated with cortisol levels (P < 0.05), but there was no effect of recent glucocorticoid exposure. These findings suggest that the preterm neonate may have lower developmental exposure to 5α-reduced steroids and may lack steroid-mediated neuroprotection depending on fetal sex.

Author(s):  
Erin V. McGillick ◽  
Sandra Orgeig ◽  
Beth J. Allison ◽  
Kirsty L. Brain ◽  
Youguo Niu ◽  
...  

Abstract Background In the fetus, the appropriate balance of prooxidants and antioxidants is essential to negate the detrimental effects of oxidative stress on lung maturation. Antioxidants improve respiratory function in postnatal life and adulthood. However, the outcomes and biological mechanisms of antioxidant action in the fetal lung are unknown. Methods We investigated the effect of maternal daily vitamin C treatment (200 mg/kg, intravenously) for a month in late gestation (105–138 days gestation, term ~145 days) on molecular regulation of fetal lung maturation in sheep. Expression of genes and proteins regulating lung development was quantified in fetal lung tissue. The number of surfactant-producing cells was determined by immunohistochemistry. Results Maternal vitamin C treatment increased fetal lung gene expression of the antioxidant enzyme SOD-1, hypoxia signaling genes (HIF-2α, HIF-3α, ADM, and EGLN-3), genes regulating sodium movement (SCNN1-A, SCNN1-B, ATP1-A1, and ATP1-B1), surfactant maturation (SFTP-B and ABCA3), and airway remodeling (ELN). There was no effect of maternal vitamin C treatment on the expression of protein markers evaluated or on the number of surfactant protein-producing cells in fetal lung tissue. Conclusions Maternal vitamin C treatment in the last third of pregnancy in sheep acts at the molecular level to increase the expression of genes that are important for fetal lung maturation in a healthy pregnancy. Impact Maternal daily vitamin C treatment for a month in late gestation in sheep increases the expression of gene-regulating pathways that are essential for normal fetal lung development. Following late gestation vitamin C exposure in a healthy pregnancy, an increase in lung gene but not protein expression may act as a mechanism to aid in the preparation for exposure to the air-breathing environment after birth. In the future, the availability/development of compounds with greater antioxidant properties than vitamin C or more specific targets at the site of oxidative stress in vivo may translate clinically to improve respiratory outcomes in complicated pregnancies at birth.


1981 ◽  
Vol 51 (2) ◽  
pp. 384-390 ◽  
Author(s):  
J. A. Kitterman ◽  
G. C. Liggins ◽  
G. A. Campos ◽  
J. A. Clements ◽  
C. S. Forster ◽  
...  

We studied the relationship of certain fetal and maternal hormones to indicators of lung maturation in 12 fetal lambs delivered at gestational ages (GA) of 123-149 days. Maternal estrogen, maternal progesterone, and fetal prolactin did not correlate with GA or the indicators of fetal lung maturation. Fetal cortisol (range 4-165 ng X ml-1) increased with advancing GA (r = 0.747, P less than 0.01). All of the following showed a wide range of late gestation and showed a significant positive correlation with fetal cortisol: lung volumes at 40 cmH2O and 10 cmH2O on the deflation during air pressure-volume studies; saturated phosphatidylcholine (SPC) in lung tissue and in lavage fluid expressed both as mg X g-1 of wet lung and as percent of total phospholipids (%PL); total SPC (lung tissue plus lavage fluid): and SPC in lavage fluid as percent of total SPC. Lung DNA correlated inversely with GA and cortisol. All variables (except lavage fluid SPC as %PL) correlated more closely with cortisol than GA. Morphological development of lung was also related more closely to cortisol than GA. These results suggest that functional lung maturity is attained late in gestation and that endogenous cortisol is an important physiological factor in control of fetal lung maturation.


2005 ◽  
Vol 317 (1) ◽  
pp. 117-126 ◽  
Author(s):  
Mahesh N. Samtani ◽  
Nancy A. Pyszczynski ◽  
Debra C. DuBois ◽  
Richard R. Almon ◽  
William J. Jusko

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