OBJECTIVE: The aim of the present study was to investigate the role of adrenomedullin (ADM) as a hypoxia-inducible marker of clinically relevant tIssue hypoxia in acute birth asphyxia of term newborn infants. METHODS: For this purpose, ADM mRNA was determined in human placental tIssue of 20 term pregnancies complicated by birth asphyxia (pH and base deficit values, clinical score). In addition, ADM mRNA was measured in leukocytes of the asphyxiated newborn infants during the first 12 h of life (n=12). Controls were available from ten healthy term pregnancies. In vitro, hypoxia-inducible expression of ADM mRNA was evaluated in human choriocarcinoma cells (BeWo) and human leukocytes exposed to hypoxia (1% O(2)) for 1-24 h. mRNA levels were measured by TaqMan real-time PCR. RESULTS: In vitro, ADM mRNA related to porphobilinogen deaminase (PBGD) mRNA levels significantly increased in response to hypoxia within a period of 4 h in leukocytes and 12 h in BeWo cells. In human placental tIssue, significantly higher levels of ADM/PBGD mRNA were present in asphyxiated newborn infants with severe hypoxic-ischemic encephalopathy (HIE) (n=5) compared with patients with mild or no HIE (n=15). Increased levels of ADM/PBGD mRNA levels were found during the first hours of life in leukocytes of neonates with severe HIE compared with controls. CONCLUSIONS: Our results indicate an upregulation of ADM gene expression in human placenta and leukocytes in clinically relevant hypoxic-ischemic birth complications and suggest ADM gene expression as a promising marker for severe complications due to perinatal asphyxia such as HIE.
R Trollmann, E Schoof, E Beinder, D Wenzel, W Rascher and J Dotsch
E Schoof, M Girstl, W Frobenius, M Kirschbaum, R Repp, I Knerr, W Rascher and J Dotsch
BACKGROUND: During human pregnancy, 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) plays an important role in protecting the fetus from high maternal glucocorticoid concentrations by converting cortisol to inactive cortisone. Furthermore, 11beta-HSD2 is indirectly involved in the regulation of the prostaglandin inactivating enzyme 15-hydroxyprostaglandin dehydrogenase (PGDH), because cortisol reduces the gene expression and enzyme activity of PGDH in human placental cells. OBJECTIVE: To examine developmental changes in placental 11beta-HSD2 and PGDH gene expression during the 2nd and 3rd trimesters of human pregnancies. METHODS: In placental tissue taken from 20 healthy women with normal pregnancy and 20 placentas of 17 mothers giving birth to premature babies, 11beta-HSD2 and PGDH mRNA expression was determined using quantitative real-time PCR. RESULTS: Placental mRNA expression of 11beta-HSD2 and PGDH increased significantly with gestational age (r=0.55, P=0.0002 and r=0.42, P=0.007). In addition, there was a significant correlation between the two enzymes (r=0.58, P<0.0001). CONCLUSIONS: In the course of pregnancy there is an increase in 11beta-HSD2 and PGDH mRNA expression in human placental tissue. This adaptation of 11beta-HSD2 prevents increasing maternal cortisol concentrations from transplacental passage and is exerted at the gene level. 11beta-HSD2 up-regulation may also lead to an increase in PGDH mRNA concentrations that, until term, possibly delays myometrial contractions induced by prostaglandins.
E Schoof, A Stuppy, F Harig, R Carbon, T Horbach, W Stohr, W Rascher and J Dotsch
OBJECTIVE: Adipose tissue displays depot-specific metabolic properties and a predominant gene expression of leptin in subcutaneous tissue. The aim of the study was to evaluate leptin mRNA expression in various adipose tissues and to relate it to plasma leptin concentrations. Furthermore, developmental changes in leptin gene expression from childhood to adulthood were examined. DESIGN AND METHODS: Thoracic subcutaneous and intrathoracic adipose tissue specimens were obtained in 22 adults (51-81 years) and 23 children (0.1-17 years) undergoing cardiac surgery, and abdominal subcutaneous, omental and mesenterial fat specimens were collected from 21 adults (38-79 years) and 22 children (0.2-17 years) before abdominal surgery. Preoperative plasma leptin concentrations were measured by RIA. Leptin mRNA expression was quantified by TaqMan real-time PCR. RESULTS: In adults, there was no difference between leptin gene expression in subcutaneous and intrathoracic fat, whereas in children leptin mRNA expression was significantly higher in subcutaneous adipose tissue. In omental fat, leptin mRNA levels were significantly lower compared with subcutaneous and mesenterial sites in both children and adults. Adults revealed a significantly higher leptin gene expression in subcutaneous, omental and mesenterial adipose tissues than children. Subcutaneous and omental leptin gene expression are independent factors for plasma leptin concentrations in children and adults. CONCLUSION: Leptin is differentially expressed at different adipose tissue sites, a situation which is even more pronounced in children. There is a developmental increase in leptin mRNA expression in adipose tissue during childhood, reaching maximal capacity in adulthood.
Stephanie C E Schuit, Frank H de Jong, Lisette Stolk, W Nadia H Koek, Joyce B J van Meurs, Mariette W C J Schoofs, M Carola Zillikens, Albert Hofman, Johannes P T M van Leeuwen, Huibert A P Pols and André G Uitterlinden
Objective: Postmenopausal estradiol (E2) levels vary widely between individuals and this variation is an important determinant of diseases such as osteoporosis. It has been suggested that the estrogen receptor alpha (ESR1) gene may influence peripheral E2 levels, but the role of common sequence variations in the ESR1 gene is unclear.
Methods: In 631 postmenopausal women and 528 men from the Rotterdam Study, a population-based, prospective cohort study of individuals aged 55 years and over, ESR1 PvuII-XbaI haplotypes were determined and correlated with plasma E2 levels.
Results: In women, haplotype 1 (T-A) was significantly associated with an allele-dose-dependent decrease in E2. After adjusting for age, body mass index, years since menopause and testosterone levels, plasma E2 levels decreased by 1.90 pmol/l per allele copy of this haplotype (P < 0.05). Extreme genotypes, representing 23 and 27% of the population, varied by 3.93 pmol/l. No association with plasma testosterone was observed. In a subset of 446 women, no association of genotype with plasma concentrations of dehydroepiandrosterone sulfate, androstenedione or estrone was seen. In men, none of the sex hormone levels was associated with the ESR1 PvuII-XbaI haplotypes.
Conclusion: We have demonstrated a role for genetic variations in the ESR1 gene in determining post-menopausal E2 levels in women.