Alternative parameters for echocardiographic assessment of fetal diastolic function

Alternative methods to assess ventricular diastolic function in the fetus are proposed. Fetal myocardial hypertrophy in maternal diabetes was used as a model of decreased left ventricular compliance (LVC), and fetal respiratory movements as a model of increased LVC. Comparison of three groups of fetuses showed that, in 10 fetuses of diabetic mothers (FDM) with septal hypertrophy (SH), the mean excursion index of the septum primum (EISP) (ratio between the linear excursion of the flap valve and the left atrial diameter) was 0.36 ± 0.09, in 8 FDM without SH it was 0.51 ± 0.09 (P = 0.001), and in the 8 normal control fetuses (NCF) it was 0.49 ± 0.12 (P = 0.003). In another study, 28 fetuses in apnea had a mean EISP of 0.39 ± 0.05 which increased to 0.57 ± 0.07 during respiration (P < 0.001). These two studies showed that the mobility of the septum primum was reduced when LVC was decreased and was increased when LVC was enhanced. Mean pulmonary vein pulsatility was higher in 14 FDM (1.83 ± 1.21) than in 26 NCF (1.02 ± 0.31; P = 0.02). In the same fetuses, mean left atrial shortening was decreased (0.40 ± 0.11) in relation to NCF (0.51 ± 0.09; P = 0.011). These results suggest that FDM may have a higher preload than normal controls, probably as a result of increased myocardial mass and LV hypertrophy. Prenatal assessment of LV diastolic function by fetal echocardiography should include analysis of septum primum mobility, pulmonary vein pulsatility, and left atrial shortening.

Cholesterol induces fetal rat enterocyte death in culture

The effect of cholesterol on fetal rat enterocytes and IEC-6 cells (line originated from normal rat small intestine) was examined. Both cells were cultured in the presence of 20 to 80 µM cholesterol for up to 72 h. Apoptosis was determined by flow cytometric analysis and fluorescence microscopy. The expression of HMG-CoA reductase and peroxisome proliferator-activated receptor gamma (PPARgamma) was measured by RT-PCR. The addition of 20 µM cholesterol reduced enterocyte proliferation as early as 6 h of culture. Reduction of enterocyte proliferation by 28 and 41% was observed after 24 h of culture in the presence and absence of 10% fetal calf serum, respectively, with the effect lasting up to 72 h. Treatment of IEC-6 cells with cholesterol for 24 h raised the proportion of cells with fragmented DNA by 9.7% at 40 µM and by 20.8% at 80 µM. When the culture period was extended to 48 h, the effect of cholesterol was still more pronounced, with the percent of cells with fragmented DNA reaching 53.5% for 40 µM and 84.3% for 80 µM. Chromatin condensation of IEC-6 cells was observed after treatment with cholesterol even at 20 µM. Cholesterol did not affect HMG-CoA reductase expression. A dose-dependent increase in PPARgamma expression in fetal rat enterocytes was observed. The expression of PPAR-gamma was raised by 7- and 40-fold, in the presence and absence of fetal calf serum, respectively, with cholesterol at 80 mM. The apoptotic effect of cholesterol on enterocytes was possibly due to an increase in PPARgamma expression.

Relationships between fetal body weight of Wistar rats at term and the extent of skeletal ossification

We investigated the relationship between fetal body weight at term (pregnancy day 21) and the extent of ossification of sternum, metacarpus, metatarsus, phalanges (proximal, medial and distal) of fore- and hindlimbs and cervical and coccygeal vertebrae in Wistar rats. The relationships between fetal body weight and sex, intrauterine position, uterine horn, horn size, and litter size were determined using historical control data (7594 fetuses; 769 litters) of untreated rats. Relationships between body weight and degree of ossification were examined in a subset of 1484 historical control fetuses (154 litters) which were subsequently cleared and stained with alizarin red S. Fetal weight was independent of horn size, uterine horn side (left or right) or intrauterine position. Males were heavier than females and fetal weight decreased with increasing litter size. Evaluation of the skeleton showed that ossification of sternum, metacarpus and metatarsus was extensively complete and independent of fetal weight on pregnancy day 21. In contrast, the extent of ossification of fore- and hindlimb phalanges and of cervical and sacrococcygeal vertebrae was dependent on fetal body weight. The strongest correlation between body weight and degree of ossification was found for hindlimb, medial and proximal phalanges. Our data therefore suggest that, in full-term rat fetuses (day 21), reduced ossification of sternum, metacarpus and metatarsus results from a localized impairment of bone calcification (i.e., a malformation or variation) rather than from general growth retardation and that ossification of hindlimb (medial and proximal) phalanges is a good indicator of treatment-induced fetal growth retardation.

A connection between extracellular matrix and hormonal signals during the development of the human fetal adrenal gland

The human adrenal cortex, involved in adaptive responses to stress, body homeostasis and secondary sexual characters, emerges from a tightly regulated development of a zone-specific secretion pattern during fetal life. Its development during fetal life is critical for the well being of pregnancy, the initiation of delivery, and even for an adequate adaptation to extra-uterine life. As early as from the sixth week of pregnancy, the fetal adrenal gland is characterized by a highly proliferative zone at the periphery, a concentric migration accompanied by cell differentiation (cortisol secretion) and apoptosis in the central androgen-secreting fetal zone. After birth, a strong reorganization occurs in the adrenal gland so that it better fulfills the newborn's needs, with aldosterone production in the external zona glomerulosa, cortisol secretion in the zona fasciculata and androgens in the central zona reticularis. In addition to the major hormonal stimuli provided by angiotensin II and adrenocorticotropin, we have tested for some years the hypotheses that such plasticity may be under the control of the extracellular matrix. A growing number of data have been harvested during the last years, in particular about extracellular matrix expression and its putative role in the development of the human adrenal cortex. Laminin, collagen and fibronectin have been shown to play important roles not only in the plasticity of the adrenal cortex, but also in cell responsiveness to hormones, thus clarifying some of the unexplained observations that used to feed controversies.

Development of fetal nicotine and muscarinic receptors in utero

The role of acetylcholine in the central and peripheral nervous systems is well established in adults. Cholinergic modulation of vascular functions and body fluid balance has been extensively studied. In the embryo-fetus, cholinergic receptors are widespread in the peripheral and central systems, including smooth muscle and the epithelial lining of the cardiovascular, digestive, and urinary systems, as well as in the brain. Fetal nicotine and muscarinic receptors develop in a pattern (e.g., amount and distribution) related to gestational periods. Cholinergic mechanisms have been found to be relatively intact and functional in the control of vascular homeostasis during fetal life in utero at least during the last third of gestation. This review focuses on the development of fetal nicotine and muscarinic receptors, and provides information indicating that central cholinergic systems are well developed in the control of fetal blood pressure and body fluid balance before birth. Therefore, the development of cholinergic systems in utero plays an important role in fetal vascular regulation, gastrointestinal motility, and urinary control.

Fetal development of regulatory mechanisms for body fluid homeostasis

The balance of body fluids is critical to health and the development of diseases. Although quite a few review papers have shown that several mechanisms, including hormonal and behavioral regulation, play an important role in body fluid homeostasis in adults, there is limited information on the development of regulatory mechanisms for fetal body fluid balance. Hormonal, renal, and behavioral control of body fluids function to some extent in utero. Hormonal mechanisms including the renin-angiotensin system, aldosterone, and vasopressin are involved in modifying fetal renal excretion, reabsorption of sodium and water, and regulation of vascular volume. In utero behavioral changes, such as fetal swallowing, have been suggested to be early functional development in response to dipsogens. Since diseases, such as hypertension, can be traced to fetal origin, it is important to understand the development of fetal regulatory mechanisms for body fluid homeostasis in this early stage of life. This review focuses on fetal hormonal, behavioral, and renal development related to regulation of body fluids in utero.

Characterization and oxygen binding properties of des-Arg human hemoglobin

The role of chloride in the stabilization of the deoxy conformation of hemoglobin (Hb), the low oxygen affinity state, has been studied in order to identify the nature of this binding. Previous studies have shown that arginines 141α could be involved in the binding of this ion to the protein. Thus, des-Arg Hb, human hemoglobin modified by removal of the α-chain C-terminal residue Arg141α, is a possible model for studies of these interactions. The loss of Arg141α and all the salt bridges in which it participates is associated with subtle structural perturbations of the α-chains, which include an increase in the conformational flexibility and further shift to the oxy state, increasing oxygen affinity. Thus, this Hb has been the target of many studies of structural and functional behavior along with medical applications. In the present study, we describe the biochemical characterization of des-Arg Hb by electrophoresis, high-performance liquid chromatography and mass spectroscopy. The effects of chloride binding on the oxygen affinity and on the cooperativity to des-Arg Hb and to native human hemoglobin, HbA, were measured and compared. We confirm that des-Arg Hb presents high oxygen affinity and low cooperativity in the presence of bound chloride and show that the binding of chloride to des-Arg does not change its functional characteristics as observed with HbA. These results indicate that Arg141α may be involved in the chloride effect on Hb oxygenation. Moreover, they show that these residues contribute to lower Hb oxygen affinity to a level compatible with its biological function.

Maternal undernutrition and the offspring kidney: from fetal to adult life

Maternal dietary protein restriction during pregnancy is associated with low fetal birth weight and leads to renal morphological and physiological changes. Different mechanisms can contribute to this phenotype: exposure to fetal glucocorticoid, alterations in the components of the renin-angiotensin system, apoptosis, and DNA methylation. A low-protein diet during gestation decreases the activity of placental 11ß-hydroxysteroid dehydrogenase, exposing the fetus to glucocorticoids and resetting the hypothalamic-pituitary-adrenal axis in the offspring. The abnormal function/expression of type 1 (AT1R) or type 2 (AT2R) AngII receptors during any period of life may be the consequence or cause of renal adaptation. AT1R is up-regulated, compared with control, on the first day after birth of offspring born to low-protein diet mothers, but this protein appears to be down-regulated by 12 days of age and thereafter. In these offspring, AT2R expression differs from control at 1 day of age, but is also down-regulated thereafter, with low nephron numbers at all ages: from the fetal period, at the end of nephron formation, and during adulthood. However, during adulthood, the glomerular filtration rate is not altered, due to glomerulus and podocyte hypertrophy. Kidney tubule transporters are regulated by physiological mechanisms; Na+/K+-ATPase is inhibited by AngII and, in this model, the down-regulated AngII receptors fail to inhibit Na+/K+-ATPase, leading to increased Na+ reabsorption, contributing to the hypertensive status. We also considered the modulation of pro-apoptotic and anti-apoptotic factors during nephrogenesis, since organogenesis depends upon a tight balance between proliferation, differentiation and cell death.

Plasma concentrations and placental immunostaining of interleukin-10 and tumornecrosis factor-α as predictors of alterations in the embryo-fetal organism and the placental development of diabetic rats

Interleukin-10 (IL-10) appears to be the key cytokine for the maintenance of pregnancy and inhibits the secretion of inflammatory cytokines such as tumor necrosis factor-α (TNF-α). However, there are no studies evaluating the profile of these cytokines in diabetic rat models. Thus, our aim was to analyze IL-10 and TNF-α immunostaining in placental tissue and their respective concentrations in maternal plasma during pregnancy in diabetic rats in order to determine whether these cytokines can be used as predictors of alterations in the embryo-fetal organism and in placental development. These parameters were evaluated in non-diabetic (control; N = 15) and Wistar rats with streptozotocin (STZ)-induced diabetes (N = 15). At term, the dams (100 days of life) were killed under anesthesia and plasma and placental samples were collected for IL-10 and TNF-α determinations by ELISA and immunohistochemistry, respectively. The reproductive performance was analyzed. Plasma IL-10 concentrations were reduced in STZ rats compared to controls (7.6 ± 4.5 vs 20.9 ± 8.1 pg/mL). The placental scores of immunostaining intensity did not differ between groups (P > 0.05). Prevalence analysis showed that the IL-10 expression followed TNF-α expression, showing a balance between them. STZ rats also presented impaired reproductive performance and reduced plasma IL-10 levels related to damage during early embryonic development. However, the increased placental IL-10 as a compensatory mechanism for the deficit of maternal regulation permitted embryo development. Therefore, the data suggest that IL-10 can be used as a predictor of changes in the embryo-fetal organism and in placental development in pregnant diabetic rats.

Plasma levels and placental expression of vaspin in pregnant women with diabetes mellitus

The present study aimed to investigate visceral adipose tissue-specific serpin (vaspin) concentrations in serum and term placentas and relate these values to insulin resistance and lipid parameters in women with gestational diabetes mellitus (GDM). A total of 30 GDM subjects and 27 age-matched pregnant women with normal glucose tolerance (NGT, control) were included. Serum glucose, glycated hemoglobin (HbA1c), lipid profile, insulin, and vaspin were measured at the end of pregnancy, and homeostasis model of assessment-insulin resistance (HOMA-IR) values were calculated. Vaspin mRNA and protein levels in placentas were measured by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting, respectively. Serum vaspin levels were significantly lower in the GDM group than in controls (0.49±0.24 vs 0.83±0.27 ng/mL, respectively; P<0.01). Three days after delivery, serum vaspin levels were significantly decreased in subjects with GDM (0.36±0.13 vs0.49±0.24 ng/mL, P<0.01). However, in the GDM group, serum vaspin levels were not correlated with the parameters evaluated. In contrast, in the control group, serum vaspin levels were positively correlated with triglycerides (TG; r=0.45, P=0.02) and very low-density lipoprotein cholesterol (VLDL-C; r=0.42, P=0.03). Placental mRNA vaspin (0.60±0.32 vs0.68±0.32, P=0.46) and protein (0.30±0.08 vs0.39±0.26; P=0.33) levels in the GDM group did not differ significantly from those in the control group, but were negatively correlated with neonatal birth weight in the GDM group (r=-0.48, P=0.03; r=-0.88; P<0.01). Our findings indicated that vaspin may be an important adipokine involved in carbohydrate and lipid metabolism and may also play a role in fetal development.

Exames de imagem na avaliação de anomalias urológicas em lactentes com hidronefrose fetal: avanços e controvérsias

Avanços recentes no diagnóstico pré-natal têm permitido o aprimoramento da detecção e o manejo das anormalidades do trato urinário. A ultrassonografia pré-natal permite o reconhecimento de anormalidades urológicas que somente seriam identificadas tardiamente, após o aparecimento de sintomas ou complicações. A uretrocistografia miccional pode ser reservada para casos selecionados. Exames de medicina nuclear devem ser realizados em casos de hidronefrose moderada e grave. O estudo consistiu de uma revisão da literatura atual sobre a abordagem pós-natal da hidronefrose fetal. Os dados obtidos foram confrontados com a experiência da Unidade de Nefrologia Pediátrica do HC/UFMG na conduta e no seguimento de crianças com diagnóstico de uropatias detectadas na investigação de hidronefrose fetal.

Human fetal malformations associated with the use of an angiotensin II receptor antagonist: Case Report

Introduction: The potential risks related to drug exposure during pregnancy represent a vast chapter in modern obstetrics and data regarding the safety of antihypertensive drugs during pregnancy are relatively scarce. Case report: A 37-year-old patient discovered her fifth pregnancy at our hospital after 26 weeks and 4 days of gestation. She reported a history of hypertension and was currently being treated with Losartan. Hospitalization was recommended for the patient and further evaluation of fetal vitality was performed. On the fourth day an ultrasound was performed, resulting in a severe oligohydramnios, fetal centralization and abnormal ductus venosus. After 36 hours, the newborn died. Pathologic evaluation: At autopsy, the skullcap had large fontanels and deficient ossification. The kidneys were slightly enlarged. A microscopic examination detected underdevelopment of the tubules and the presence of some dilated lumens. Immunohistochemical detection of epithelial membrane antigen was positive. Immunoreactivity of CD 15 was also assayed to characterize the proximal tubules, and lumen collapse was observed in some regions. Discussion: Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor antagonists (ARAs) are among the most widely prescribed drugs for hypertension. They are often used by hypertensive women who are considering become pregnant. While their fetal toxicity in the second or third trimesters has been documented, their teratogenic effect during the first trimester has only recently been demonstrated. Conclusion: Constant awareness by physicians and patients should be encouraged, particularly in regard to the prescription of antihypertensive drugs in women of childbearing age who are or intend to become pregnant.