Background: Evidence suggests that increasing salt intake in pregnancy lowers blood pressure, protecting against preeclampsia. We hypothesized that sodium (Na) evokes beneficial placental signals that are disrupted in preeclampsia.
Methods: Blood and urine were collected from nonpregnant women of reproductive age (n=26) and pregnant women with (n=50) and without (n=55) preeclampsia, along with placental biopsies.
Extra-adrenal de novo aldosterone (Aldo) production has been described inconsistently. Systematic data based upon state-of-the-art technology including validated controls are sparse. We hypothesized that aldosterone synthase (CYP11B2) expression and de novo Aldo production are absent in nonadrenal human cell lines, either immortalized cell lines or commercially available primary cell lines, including peripheral blood mononuclear cells (PBMCs) of individuals without and with primary hyperaldosteronism (PA).
View Article and Find Full Text PDFAims: Glomerular damage indicated by proteinuria is a main symptom in diabetic nephropathy. Mineralocorticoid receptor (MR) antagonists (MRAs) are beneficial irrespective of aldosterone availability. Thus, we hypothesized an alternatively activated MR to promote glomerular damage in proteinuric diabetic nephropathy.
View Article and Find Full Text PDFThe steroid hormone progesterone accounts for immune tolerance in pregnancy. Enhanced progesterone metabolism to 6α-OH-pregnanolone occurs in complicated pregnancies such as in preeclampsia with preterm delivery or intrauterine growth restriction, and in cancer. As lymphatic endothelial cells (LECs) promote tumor immunity, we hypothesized that human LECs modify progesterone bioavailability.
View Article and Find Full Text PDFBackground In pregnancy, a high plasma volume maintains uteroplacental perfusion and prevents placental ischemia, a condition linked to elevated maternal blood pressure ( BP ). Reducing BP by increasing Na intake via plasma volume expansion appears contra-intuitive. We hypothesize that an appropriate Na intake in pregnancy reduces maternal BP and adapts the renin-angiotensin system in a pregnancy-specific manner.
View Article and Find Full Text PDFAldosterone is an important factor supporting placental growth and fetal development. Recently, expression of placental growth factor (PlGF) has been observed in response to aldosterone exposure in different models of atherosclerosis. Thus, we hypothesized that aldosterone up-regulates growth-adaptive angiogenesis in pregnancy, via increased placental PlGF expression.
View Article and Find Full Text PDFBackground: Normal pregnancy depends on pronounced adaptations in steroid hormone concentrations. Although in recent years, the understanding of these hormones in pregnancy has improved, the interpretation is hampered by insufficient reference values. Our aim was to establish gestation-specific reference intervals for spot urinary steroid hormone levels in normal singleton pregnancies and 6 weeks postpartum.
View Article and Find Full Text PDFA successful pregnancy requires an accommodating environment. Salt and water availability are critical for plasma volume expansion. Any changes in sodium intake would alter aldosterone, a hormone previously described beneficial in pregnancy.
View Article and Find Full Text PDFAldosterone levels are markedly elevated during normal pregnancy but fall even though volume contracts when preeclampsia occurs. The level of aldosterone in either condition cannot be explained solely by the activity of the renin-angiotensin II system. In normal gestation, vascular endothelial growth factor (VEGF) is thought to maintain vascular health, but its role in adrenal hormone production is unknown.
View Article and Find Full Text PDFPregnancy Hypertens
July 2012
Introduction: Angiogenic signals are a vital signal of placental integrity. Aldosterone has recently been shown to enhance placental growth factor (PlGF) expression in the peripheral vasculature [1] and to promote trophoblast growth [2]. The plgf gene possesses a functional mineralocorticoid receptor responsive element in the promoter region.
View Article and Find Full Text PDFIntroduction: Adrenal aldosterone production depends upon capillary integrity. Inadequately explained by increased renin secretion, aldosterone is high in pregnancy, a proangiogenic state. In preeclampsia, low aldosterone levels coincide with disturbed endothelial integrity due to disrupted VEGF signaling.
View Article and Find Full Text PDFBackground: Glucocorticoids (GC) are potent anti-inflammatory and immunosuppressive steroid hormones, mainly produced by the adrenal glands. However, increasing evidence supports the idea of additional extra-adrenal sources of bioactive GC. The lung epithelium is constantly exposed to a plethora of antigenic stimuli, and local GC synthesis could contribute to limit uncontrolled immune reactions and tissue damage.
View Article and Find Full Text PDFDuring pregnancy, trophoblasts grow to adapt the feto-maternal unit to fetal requirements. Aldosterone and cortisol levels increase, the latter being inactivated by a healthy placenta. By contrast, preeclamptic placental growth is reduced while aldosterone levels are low and placental cortisol tissue levels are high due to improper deactivation.
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