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The placenta is a temporary organ with a unique structure and function to ensure healthy fetal development. Placental dysfunction is involved in pre-eclampsia (PE), fetal growth restriction, preterm birth, and gestational diabetes mellitus (GDM). A diabetic state affects maternal and fetal health and may lead to functional alterations of placental metabolism, inflammation, hypoxia, and weight, amplifying the fetal stress. The placental molecular adaptations to the diabetic environment and the adaptive spatio-temporal consequences to elevated glucose or insulin are largely unknown (2). We aimed to identify gene expression signatures related to the diabetic placental pathology of placentas from women with diabetes mellitus. Human placenta samples ( n = 77) consisting of healthy controls, women with either gestational diabetes mellitus (GDM), type 1 or type 2 diabetes, and women with GDM, type 1 or type 2 diabetes and superimposed PE were collected. Interestingly, gene expression differences quantified by total RNA sequencing were mainly driven by fetal sex rather than clinical diagnosis. Association of the principal components with a full set of clinical patient data identified fetal sex as the single main explanatory variable. Accordingly, placentas complicated by type 1 and type 2 diabetes showed only few differentially expressed genes, while possible effects of GDM and diabetic pregnancy complicated by PE were not identifiable in this cohort. We conclude that fetal sex has a prominent effect on the placental transcriptome, dominating and confounding gene expression signatures resulting from diabetes mellitus in settings of well-controlled diabetic disease. Our results support the notion of placenta as a sexual dimorphic organ.

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Preeclampsia (PE) is characterized by the onset of hypertension (≥140/90 mmHg) and presence of proteinuria (>300 mg/L/24 h urine) or other maternal organ dysfunctions. During human PE, renal injuries have been observed. Some studies suggest that women with PE diagnosis have an increased risk to develop renal diseases later in life. However, in human studies PE as a single cause of this development cannot be investigated. Here, we aimed to investigate the effect of PE on postpartum renal damage in an established transgenic PE rat model. Female rats harboring the human-angiotensinogen gene develop a preeclamptic phenotype after mating with male rats harboring the human-renin gene, but are normotensive before and after pregnancy. During pregnancy PE rats developed mild tubular and glomerular changes assessed by histologic analysis, increased gene expression of renal damage markers such as kidney injury marker 1 and connective-tissue growth factor, and albuminuria compared to female wild-type rats (WT). However, four weeks postpartum, most PE-related renal pathologies were absent, including albuminuria and elevated biomarker expression. Only mild enlargement of the glomerular tuft could be detected. Overall, the glomerular and tubular function were affected during pregnancy in the transgenic PE rat. However, almost all these pathologies observed during PE recovered postpartum.

Objective: Preeclampsia is associated with an elevated risk of cardiovascular disease later in life. Women with a history of preeclampsia are at risk of developing hypertension as well as ischemic heart disease. Identification of women at the highest risk is important to initiate preventive strategies. We investigated whether high-sensitivity cardiac troponin I (hs-cTnI) levels are associated with a history of early-onset preeclampsia, and with hypertension in these high-risk women., Methods: Approximately 9-10 years after pregnancy, hs-cTnI levels were measured for 339 women of the Preeclampsia Risk Evaluation in FEMales cohort, consisting of 177 women with a history of early-onset preeclampsia and 162 women with a previous uncomplicated index pregnancy. Associations were analyzed using several statistical tests and linear regression analysis., Results: The median hs-cTnI levels (IQR) were 2.50 ng/l (2.30) in women with a history of early-onset preeclampsia and 2.35 ng/l (2.50) in women without a history of preeclampsia, P = 0.53. Among women with a history of early-onset preeclampsia, the hs-cTnI levels were higher in women who were hypertensive compared with their normotensive counterparts (medians 2.60 versus 2.30; P = 0.03). In addition, blood pressure levels increased with increasing hs-cTnI levels., Conclusion: We did not find a difference in hs-cTnI levels between women with and without a history of early-onset preeclampsia. Nonetheless, hs-cTnI levels were statistically significantly higher in current hypertensive women with a history of preeclampsia compared with their normotensive counterparts. Therefore, hs-cTnI levels might improve risk prediction for women at the highest risk of cardiovascular disease.

Pregnancy-induced hypertension is a severe pregnancy complication, increasing risk of long-term cardiovascular disease in mothers and offspring. We hypothesized that maternal blood pressure in pregnancy associated with offspring blood pressure; that the associations were sex-specific; and that maternal circulating placental angiogenic markers (PlGF [placental growth factor] and sFlt-1 [soluble fms-like tyrosine kinase-1]) mediated this relationship. We analyzed data from 2434 women and 2217 children from the Odense Child Cohort, a prospective Danish cohort study. Offspring blood pressure trajectory from 4 months to 5 years was highly associated to maternal first, second, and third trimester blood pressure, and mean blood pressure in pregnancy, independent of maternal and offspring covariates. There were offspring sex-specific associations: Girls from mothers in the highest quartile of first and third trimester blood pressure had significantly higher systolic blood pressure at 5 years than the rest of the cohort (mean difference±SEM: 1.81±0.59 and 2.11±0.59 mm Hg, respectively, all P <0.01); whereas boys had significantly higher diastolic blood pressure at 5 years (mean difference±SEM: 1.11±0.45 and 1.03±0.45, respectively, all P <0.05). Concentrations of PlGF at gestational week 28 correlated inversely to maternal gestational blood pressure trajectory, independent of the diagnosis of pregnancy-induced hypertension, adjusted β coefficients (95% CI) for predicting systolic blood pressure (SBP): -3.18 (-4.66 to -1.70) mm Hg, for predicting diastolic blood pressure (DBP): -2.48 (-3.57 to -1.40) mm Hg. In conclusion, maternal gestational blood pressure predicted offspring blood pressure trajectory until 5 years in a sex-differential manner. Furthermore, subtle alterations in blood pressure in early pregnancy preceded hypertension or preeclampsia, and PlGF was a mediator of cardiovascular health in pregnancy.

Several studies have shown that women with a preeclamptic pregnancy exhibit an increased risk of cardiovascular disease. However, the underlying molecular mechanisms are unknown. Animal models are essential to investigate the causes of this increased risk and have the ability to assess possible preventive and therapeutic interventions. Using the latest technologies such as speckle tracking echocardiography (STE), it is feasible to map subclinical changes in cardiac diastolic and systolic function as well as structural changes of the maternal heart. The aim of this work is to compare cardiovascular changes in an established transgenic rat model with preeclampsia-like pregnancies with findings from human preeclamptic pregnancies by STE. The same algorithms were used to evaluate and compare the changes in echoes of human and rodents. Parameters of functionality such as global longitudinal strain (animal -23.54 ± 1.82% vs. -13.79 ± 0.57%, human -20.60 ± 0.47% vs. -15.45 ± 1.55%) as well as indications of morphological changes such as relative wall thickness (animal 0.20 ± 0.01 vs. 0.25 ± 0.01, human 0.34 ± 0.01 vs. 0.40 ± 0.02) are significantly altered in both species after preeclamptic pregnancies. Thus, the described rat model simulates the human situation quite well and is a valuable tool for future investigations regarding cardiovascular changes. STE is a unique technique that can be applied in animal models and humans with a high potential to uncover cardiovascular maladaptation and subtle pathologies.

Preeclampsia is associated with increased cardiovascular long-term risk; however, the underlying functional and structural mechanisms are unknown. We investigated maternal cardiac alterations after preeclampsia. Female rats harboring the human angiotensinogen gene [TGR(hAogen)L1623] develop a preeclamptic phenotype with hypertension and albuminuria during pregnancy when mated with male rats bearing the human renin gene [TGR(hRen)L10J] but behave physiologically normal before and after pregnancy. Furthermore, rats were treated with pravastatin. We tested the hypothesis that statins are a potential therapeutic intervention to reduce cardiovascular alterations due to simulated preeclamptic pregnancy. Although hypertension persists for only 8 days in pregnancy, former preeclampsia rats exhibit significant cardiac hypertrophy 28 days after pregnancy observed in both speckle tracking echocardiography and histological staining. In addition, fibrosis and capillary rarefaction was evident. Pravastatin treatment ameliorated the remodeling and improved cardiac output postpartum. Preeclamptic pregnancy induces irreversible structural changes of cardiac hypertrophy and fibrosis, which can be moderated by pravastatin treatment. This pathological cardiac remodeling might be involved in increased cardiovascular risk in later life.

The mineralocorticoid aldosterone increases in plasma in healthy pregnancy along with renin and angiotensin II and plays a key role in the physiological plasma volume expansion. In mice, aldosterone contributes to an optimal fetal development by enhancing PlGF (placental growth factor) expression and trophoblast cell proliferation. In preeclampsia, there is coincident suppression of aldosterone and impaired placental development. We hypothesized that aldosterone independently contributes to placental and birth weight in humans, and high dietary sodium and low potassium intakes affect this relationship adversely. We analyzed 24-hour urine collections and plasma samples from gestational week 29 in a subsample of 569 pregnant women from the Odense Child Cohort-a Danish population-based longitudinal cohort study. Plasma and urinary aldosterone were measured by ELISA, sodium and potassium excretions by flame photometer. Predictive values of aldosterone levels and sodium and potassium intakes were assessed by multiple and Cox regression analyses. Primary outcomes were placental weight and birth weight. Secondary outcome was preeclampsia. Urinary aldosterone excretion at gestational week 29 independently contributed to placental and birth weights (adjusted β-coefficients [95% CI], 24.50 [9.66-39.35] and 9.59 [4.57-14.61], respectively). Aldosterone levels were not associated to preeclampsia incidence. Salt intake >6 g/d was associated with development of preeclampsia (hazard ratio [95% CI], 5.68 [1.51-21.36]). At gestational week 29, urinary aldosterone excretion is an independent predictor of placental and birth weights. High salt intake is a risk factor for preeclampsia. In perspective, suppression of aldosterone in pregnancy has adverse trophic effects.