Decreased gene expression of 11β-hydroxysteroid dehydrogenase type 2 and 15-hydroxyprostaglandin dehydrogenase in human placenta of patients with preeclampsia

Cortisol reduces the activity of the PG-inactivating enzyme 15-hydroxyprostaglandin dehydrogenase (PGDH) in human placental cells. The objective was to investigate a possible relation between 11 beta -hydroxysteroid dehydrogenase type 2 (11 beta -HSD2), converting cortisol to cortisone, and PGDH gene expression in the placenta of patients with preeclampsia. In placental tissue taken from 20 healthy women with normal pregnancy, 20 premature babies born after labor before term, and 18 neonates after preeclamptic pregnancy, 11 beta -HSD2 and PGDH messenger RNA (mRNA) expression was determined using quantitative TaqMan real-time PCR and quantitative competitive PCR. When comparing matched pairs, there were 3-fold lower 11 beta -HSD2/glyceraldehyde-3-phosphate dehydrogenase (11 beta -HSD2/GAPDH) mRNA levels in placentas of patients with preeclampsia than in controls [0.18 +/- 0.04 relative units (RU) and 0.61 +/- 0.10 RU, P = 0.0003]. We also found a 2-fold reduction in placental PGDH/GAPDH mRNA concentrations (0.28 +/- 0.15 RU and 0.50 +/- 0.18 RU, P = 0.0003). PGDH and 11 beta -HSD2 mRNA. levels correlated significantly (r = 0.66, P < 0.0001). In term placenta, 11<beta>-HSD2/GAPDH, but not PGDH, showed a significant correlation to birth weight (r = 0.43, P = 0.01) and to placental weight (r = 0.47, P = 0.01). Results could be confirmed by competitive PCR. We conclude that, in preeclampsia, 11 beta -HSD2 mRNA expression is reduced, leading to the known decrease of 11 beta -HSD2 activity. By means of an autocrine or paracrine mechanism, the diminished conversion of placental cortisol may lead to reduced PGDH mRNA expression as found in the present study.