Attenuation of atherogenic apo B-48-dependent hyperlipidemia and high density lipoprotein remodeling induced by vitamin C and E combination and their beneficial effect on lethal ischemic heart disease in mice.

BACKGROUND AND AIMS: Atherosclerotic cardiovascular disease is highly prevalent and its underlying pathogenesis involves dyslipidemia including pro-atherogenic high density lipoprotein (HDL) remodeling. Vitamins C and E have been proposed as atheroprotective agents for cardiovascular disease management. However, their effects and benefits on high density lipoprotein function and remodeling are unknown. In this study, we evaluated the role of vitamin C and E on non HDL lipoproteins as well as HDL function and remodeling, along with their effects on inflammation/oxidation biomarkers and atherosclerosis in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. METHODS AND RESULTS: Mice were pre-treated for 5 weeks before and during atherogenic diet feeding with vitamin C and E added to water and diet, respectively. Compared to a control group, combined vitamin C and E administration reduced serum total cholesterol and triglyceride levels by decreasing apo B-48-containing lipoproteins, remodeled HDL particles by reducing phospholipid as well as increasing PON1 and apo D content, and diminished PLTP activity and levels. Vitamin supplementation improved HDL antioxidant function and lowered serum TNF-α levels. Vitamin C and E combination attenuated atherogenesis and increased lifespan in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. CONCLUSIONS: Vitamin C and E administration showed significant lipid metabolism regulating effects, including HDL remodeling and decreased levels of apoB-containing lipoproteins, in mice. In addition, this vitamin supplementation generated a cardioprotective effect in a murine model of severe and lethal atherosclerotic ischemic heart disease.

Maternal obesity modulates intracellular lipid turnover in the human term placenta.

BACKGROUND: Obesity before pregnancy is associated with impaired metabolic status of the mother and the offspring later in life. These adverse effects have been attributed to epigenetic changes in utero, but little is known about the role of placental metabolism and its contribution to fetal development. OBJECTIVES: We examined the impact of maternal pre-pregnancy obesity on the expression of genes involved in placental lipid metabolism in lean and obese women. SUBJECTS/METHODS: Seventy-three lean and obese women with healthy pregnancy were recruited at term elective cesarean delivery. Metabolic parameters were measured on maternal venous blood samples. Expression of 88 genes involved in lipid metabolism was measured in whole placenta tissue. Proteins of genes differently expressed in response to maternal obesity were quantified, correlated with maternal parameters and immunolocalized in placenta sections. Isolated primary trophoblasts were used for in vitro assays. RESULTS: Triglyceride (TG) content was increased in placental tissue of obese (1.10, CI 1.04-1.24 mg g-1, P<0.05) vs lean (0.84, CI 0.72-1.02 mg g-1) women. Among target genes examined, six showed positive correlation (P<0.05) with maternal pre-pregnancy BMI, namely ATGL (PNPLA2), FATP1 (SLC27A1), FATP3 (SLC27A3), PLIN2, PPARG and CGI-58 (ABHD5). CGI-58 protein abundance was twofold higher (P<0.001) in placentas of obese vs lean women. CGI-58 protein levels correlated positively with maternal insulin levels and pre-pregnancy body mass index (R=0.63, P<0.001 and R=0.64, P<0.001, respectively). CGI-58 and PLIN2 were primarily located in the syncytiotrophoblast and, were upregulated (1.38- and 500-fold, respectively) upon oleic acid and insulin treatment of cultured trophoblast cells. CONCLUSION: Pre-gravid obesity significantly modifies the expression of placental genes related to transport and storage of neutral lipids. We propose that the upregulation of CGI-58, a master regulator of TG hydrolysis, contributes to the turnover of intracellular lipids in placenta of obese women, and is tightly regulated by metabolic factors of the mother.

Sex differences in the association of cord blood insulin with subcutaneous adipose tissue in neonates.

BACKGROUND: Excessive fat accumulation characterizes the over-nourished fetus in maternal diabetes and obesity with fetal insulin regarded as a primary driver. This study tested whether fetal insulin is related to subcutaneous adipose tissue (SAT) thickness at different body sites in neonates, and whether sites respond differentially to insulin. In addition, sex differences were assessed. METHODS: Cord blood insulin was measured for 414 neonates. After birth, SAT thickness was measured at 15 body sites using a validated device, a lipometer, that measures back-scattered light intensities corresponding to SAT. Associations between fetal insulin and SAT were assessed in linear regression models, adjusted for gestational age and birth weight, for males and females separately. RESULTS: No sex differences in insulin levels or total SAT thickness were found. In males, SAT thickness at most body sites was significantly correlated with insulin, with strongest associations between insulin and SAT on neck (beta 0.23, 95% CI 0.05; 0.41; P=0.01) and upper abdomen (beta 0.18, 95% CI 0.01; 0.36; P=0.04). In females, insulin was only associated with hip SAT thickness (beta 0.22, 95% CI 0.06; 0.39; P=0.01). Total SAT thickness was correlated with insulin in males (beta 0.03, 95% CI 0.01; 0.04; P=0.003), but not in females (beta 0.01, 95% CI -0.01; 0.02; P=0.38). CONCLUSIONS: Fat deposition in female neonates seems less affected by insulin as compared to males. This may reflect lower insulin sensitivity in females, or may be accounted for by other metabolic/endocrine factors overriding the association.

Hofbauer cells of M2a, M2b and M2c polarization may regulate feto-placental angiogenesis.

The human placenta comprises a special type of tissue macrophages, the Hofbauer cells (HBC), which exhibit M2 macrophage phenotype. Several subtypes of M2-polarized macrophages (M2a, M2b and M2c) exist in almost all tissues. Macrophage polarization depends on the way of macrophage activation and leads to the expression of specific cell surface markers and the acquisition of specific functions, including tissue remodeling and the promotion of angiogenesis. The placenta is a highly vascularized and rapidly growing organ, suggesting a role of HBC in feto-placental angiogenesis. We here aimed to characterize the specific polarization and phenotype of HBC and investigated the role of HBC in feto-placental angiogenesis. Therefore, HBC were isolated from third trimester placentas and their phenotype was determined by the presence of cell surface markers (FACS analysis) and secretion of cytokines (ELISA). HBC conditioned medium (CM) was analyzed for pro-angiogenic factors, and the effect of HBC CM on angiogenesis, proliferation and chemoattraction of isolated primary feto-placental endothelial cells (fpEC) was determined in vitro Our results revealed that isolated HBC possess an M2 polarization, with M2a, M2b and M2c characteristics. HBC secreted the pro-angiogenic molecules VEGF and FGF2. Furthermore, HBC CM stimulated the in vitro angiogenesis of fpEC. However, compared with control medium, chemoattraction of fpEC toward HBC CM was reduced. Proliferation of fpEC was not affected by HBC CM. These findings demonstrate a paracrine regulation of feto-placental angiogenesis by HBC in vitro Based on our collective results, we propose that the changes in HBC number or phenotype may affect feto-placental angiogenesis.

Myeloperoxidase enhances the migration and invasion of human choriocarcinoma JEG-3 cells.

Myeloperoxidase (MPO) is one of the most abundant proteins in neutrophil granules. It catalyzes the production of reactive oxygen species, which are important in inflammation and immune defense. MPO also binds to several proteins, lipids, and DNA to alter their function. MPO is present at the feto-maternal interface during pregnancy, where neutrophils are abundant. In this study, we determined the effect of MPO on JEG-3 human choriocarcinoma cells as a model of extravillous trophoblasts (EVTs) during early pregnancy. We found that MPO was internalized by JEG-3 cells and localized to the cytoplasm and nuclei. MPO internalization and activity enhanced JEG-3 cell migration and invasion, whereas this effect was impaired by pre-treating cells with heparin, to block cellular uptake, and MPO-activity inhibitor 4-ABAH. This study identifies a novel mechanism for the effect of MPO on EVT function during normal pregnancy and suggests a potential role of MPO in abnormal pregnancies.

Fetal anterior wall thickness and amniotic fluid insulin levels: an interdependence?

PURPOSE: Excessive fetal fat as the hallmark of GDM pregnancy complications is one consequence of fetal hyperinsulinism. Noninvasive methods for fetal surveillance and measurement of fetal fat are needed. The purpose of this study was to test the hypothesis that measurements of the fetal anterior abdominal wall thickness (AAWT) in women with GDM will allow early detection of fetal hyperinsulinism. MATERIALS AND METHODS: Amniocentesis was performed between 28 and 32 weeks of gestation (wks) in 220 women with GDM (diagnosed by 75 g oGTT at 24 to 28 wks). Amniotic fluid insulin levels (AFIL) were determined by a commercially available radioimmunoassay. Transabdominal ultrasound provided fetal biometric measurements following standard procedures and the AAWT including fetal skin and subcutaneous tissue at the time of amniocentesis. Maternal parameters (weight, BMI, oGTT blood glucose levels and mean daily blood glucose levels) were correlated with fetal biometric data and with AFIL. RESULTS: There was no difference in AAWT in women with GDM and no correlation with mean AFIL. AFIL also did not correlate with any other fetal measurement or with mean oGTT blood glucose levels. AFIL only showed a correlation with maternal weight (p = 0.02) and maternal BMI (p = 0.01). The correlation was present for values both before pregnancy and at the time of amniocentesis. CONCLUSION: In the early third trimester, AAWT measurements do not correlate with fetal insulin levels.

Haemodynamic effects of carbetocin and oxytocin given as intravenous bolus on women undergoing caesarean delivery: a randomised trial.

OBJECTIVE: This study compares the maternal heart rate effects of carbetocin and oxytocin during elective caesarean delivery. DESIGN: Double blind randomised single centre study (1:1). SETTING: University hospital providing intrapartum care. POPULATION: Fifty-six women undergoing elective caesarean section after spinal anaesthesia. METHODS: Haemodynamic parameters were measured non-invasively using the Task Force(®) Monitor 3040i system. Measurements were taken for 500 seconds upon administration of a slow intravenous bolus of the clinically recommended doses of 100 µg of carbetocin or 5 IU of oxytocin to prevent postpartum haemorrhage (PPH). MAIN OUTCOME MEASURE: Effect on maternal heart rate (HR). RESULTS: Statistically indistinguishable haemodynamic effects were seen for both drugs, with a maximal effect at about 30-40 seconds: HR increased 17.98 ± 2.53 bpm for oxytocin and 14.20 ± 2.45 bpm for carbetocin. Systolic blood pressure (sBP) decreased (-26.80 ± 2.82 mmHg for oxytocin versus -22.98 ± 2.75 mmHg for carbetocin). Following the maximal effect, women treated with carbetocin recovered slowly to baseline values asymptotically (HR and BP), whereas women treated with oxytocin displayed a slight rebound bradycardia at 200 seconds (-6.8 ± 1.92 bpm). Patients under both treatments showed a similar profile of side effects without any indication of unexpected adverse effects. CONCLUSION: Both oxytocins have comparable haemodynamic effects and are uterotonic drugs with an acceptable safety profile for prophylactic use. Minimal differences in the recovery phase beyond 70 seconds are in keeping with the fact that carbetocin has an extended half-life compared with oxytocin.

Dysregulation of placental endothelial lipase and lipoprotein lipase in intrauterine growth-restricted pregnancies.

CONTEXT: Fetal supply of maternally derived fatty acids requires lipase-mediated hydrolysis of lipoprotein-borne triglycerides and phospholipids at the placental surface. OBJECTIVE: The objective of the study was to test the hypothesis that members of the triglyceride lipase gene (TLG) family are expressed in the human placenta at the maternoplacental (syncytiotrophoblast) and fetoplacental (endothelial cells) interface and that their expression is altered in pregnancy pathologies. DESIGN AND SETTING: Expression of TLG family members in primary placental cells (trophoblast and endothelial cells) and tissues of first-trimester and term human placenta was analyzed by microarrays, RT-PCR, Western blotting, and immunohistochemistry. Their expression was compared between normal pregnancies and those complicated with intrauterine growth restriction (IUGR). PARTICIPANTS: Participants included women with uncomplicated pregnancies and pregnancies complicated by IUGR. RESULTS: Endothelial lipase (EL) and lipoprotein lipase (LPL) were the only lipases among the TLG family expressed in key cells of the human placenta. In first trimester, EL and LPL were expressed in trophoblasts. At term, EL was detected in trophoblasts and endothelial cells, whereas LPL was absent in these cells. Both lipases were found at placental blood vessels, EL in vascular endothelial cells and LPL in the surrounding smooth muscle cells. In total placental tissue EL expression prevails in first trimester and at term. Compared with normal placentas, EL mRNA was decreased (30%; P < 0.02), whereas LPL mRNA expression was increased (2.4-fold; P < 0.015) in IUGR. CONCLUSION: EL is the predominant TLG family member in the human placenta present at both interfaces. EL and LPL are dysregulated in IUGR.

IFPA meeting 2015 workshop report III: nanomedicine applications and exosome biology, xenobiotics and endocrine disruptors and pregnancy, and lipid.

Workshops are an important part of the IFPA annual meeting, as they allow for discussion of specialized topics. At the IFPA meeting 2015 there were twelve themed workshops, three of which are summarized in this report. These workshops were related to various aspects of placental biology but collectively covered areas of pregnancy pathologies and placental metabolism: 1) nanomedicine applications and exosome biology; 2) xenobiotics and endocrine disruptors and pregnancy; 3) lipid mediators and placental function.

Computational modelling of fatty acid transport in the human placenta.

Fatty acids are critical for normal fetal growth and development. The placenta mediates the transfer of fatty acids from the maternal to the fetal circulation. Yet, the mechanisms of fatty acid transport are not fully understood. The development of a computational model alongside experiments will test our understanding of the transfer mechanisms. Modelling experimental data suggest the presence of a metabolic pool within placental tissue that could represent the rate-limiting factor for fatty acid transfer. In addition the model suggests a slower flux capacity of the fetal-side of the placenta compared with the maternal-side. The model provides key insights into placental fatty acid transfer which will form the basis for future experimentation.

Selective cholesteryl ester uptake from high density lipoprotein by human first trimester and term villous trophoblast cells.

As villous trophoblast does represent the contact zone between foetal and maternal tissues, the present in vitro study was aimed at investigating cholesterol supply from human high density lipoprotein subclass 3 (HDL(3)) to trophoblast cells isolated from human first trimester and term placenta. Binding of (125)I-HDL(3) was specific and saturable with similar K(d)-values for first trimester (54 microg HDL(3)-protein/ml) and term villous trophoblast cells (29 microg HDL(3)-protein/ml). The cell-association of (125)I-HDL(3) was 3-fold higher for term trophoblast cells while the specific cell-association of [(3)H]cholesterol ester(CE)-labelled HDL(3) was higher for first trimester trophoblast preparations. As a consequence, first trimester trophoblast cells have a pronounced capacity for selective CE-uptake from HDL(3). Competition experiments with native and oxidized low-density lipoprotein as well as cAMP-mediated stimulation of cell-association of [(3)H]CE-HDL(3) in both trophoblast preparations suggested the scavenger receptor class B, type I (SR-BI) as a likely receptor mediating this pathway. SR-BI m RNA could be identified by RT-PCR and Northern blot experiments in both trophoblast preparations. Western blot analysis and immunocytochemistry revealed high expression of SR-BI in first trimester trophoblast. A polyclonal antiserum raised against murine SR-BI significantly decreased cell-association of [(3)H]CE-HDL(3) in trophoblast cells. We conclude that human first trimester and term trophoblast cells express SR-BI which could serve as an efficient route for supplying cholesterol esters from maternal lipoproteins to foetal tissues.

IFPA Meeting 2013 Workshop Report III: maternal placental immunological interactions, novel determinants of trophoblast cell fate, dual ex vivo perfusion of the human placenta.

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialised topics. At IFPA meeting 2013 there were twelve themed workshops, three of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of placental function, cell turnover and immunology: 1) immunology; 2) novel determinants of placental cell fate; 3) dual perfusion of human placental tissue.

Attenuation of atherogenic apo B-48-dependent hyperlipidemia and high density lipoprotein remodeling induced by vitamin C and E combination and their beneficial effect on lethal ischemic heart disease in mice

BACKGROUND AND AIMS: Atherosclerotic cardiovascular disease is highly prevalent and its underlying pathogenesis involves dyslipidemia including pro-atherogenic high density lipoprotein (HDL) remodeling. Vitamins C and E have been proposed as atheroprotective agents for cardiovascular disease management. However, their effects and benefits on high density lipoprotein function and remodeling are unknown. In this study, we evaluated the role of vitamin C and E on non HDL lipoproteins as well as HDL function and remodeling, along with their effects on inflammation/ oxidation biomarkers and atherosclerosis in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. METHODS AND RESULTS: Mice were pre-treated for 5 weeks before and during atherogenic diet feeding with vitamin C and E added to water and diet, respectively. Compared to a control group, combined vitamin C and E administration reduced serum total cholesterol and triglyceride levels by decreasing apo B-48-containing lipoproteins, remodeled HDL particles by reducing phospholipid as well as increasing PON1 and apo D content, and diminished PLTP activity and levels. Vitamin supplementation improved HDL antioxidant function and lowered serum TNF-α levels. Vitamin C and E combination attenuated atherogenesis and increased lifespan in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. CONCLUSIONS: Vitamin C and E administration showed significant lipid metabolism regulating effects, including HDL remodeling and decreased levels of apoB-containing lipoproteins, in mice. In addition, this vitamin supplementation generated a cardioprotective effect in a murine model of severe and lethal atherosclerotic ischemic heart disease.

IFPA Meeting 2011 workshop report I: Placenta: Predicting future health; roles of lipids in the growth and development of feto-placental unit; placental nutrient sensing; placental research to solve clinical problems--a translational approach.

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2011 there were twelve themed workshops, four of which are summarized in this report. These workshops related to both basic science and clinical research into placental growth and nutrient sensing and were divided into 1) placenta: predicting future health; 2) roles of lipids in the growth and development of feto-placental unit; 3) placental nutrient sensing; 4) placental research to solve clinical problems: a translational approach.

Insulin control of placental gene expression shifts from mother to foetus over the course of pregnancy.

AIMS/HYPOTHESIS: The human placenta is a complex organ situated at the interface between mother and foetus that separates maternal from foetal blood. The placental surfaces exposed to the two bloodstreams are different, i.e. trophoblasts and endothelial cells are in contact with the maternal and foetal circulation, respectively. Both cell types produce high insulin receptor levels. The aim of the present study was to test the hypothesis that spatio-temporal changes in insulin receptor expression in trophoblasts from first trimester to the endothelium at term shift the control of insulin-dependent processes from mother to foetus. METHODS: Global microarray analysis of primary trophoblasts from first trimester and term human placentas and endothelial cells from term human placentas cultured under hyperinsulinaemic and control conditions identified different sets of regulated genes in trophoblasts and endothelial cells. RESULTS: Insulin effects on placental gene expression underwent developmental changes from trophoblasts in the first trimester to endothelial cells at term that were paralleled by changes in levels of activated insulin receptors. The changes in gene regulation were both quantitative (i.e. magnitude of effect) and qualitative (i.e. specific genes affected and direction of regulation). CONCLUSIONS/INTERPRETATION: This spatio-temporal shift in insulin sensitivity throughout pregnancy allows maternal and foetal insulin to regulate different processes within the placenta at different gestational stages, facilitated by compartmentalisation of the insulin response. Thus, by altering the levels and function of insulin receptors in space and time, control of insulin-dependent processes in the human placenta will change from mother to foetus throughout gestation. This will be of particular interest in conditions associated with altered maternal or foetal insulin levels, i.e. diabetes mellitus or intrauterine growth restriction.