The role of mesenchymal stem cells in early programming of adipose tissue in the offspring of women with obesity.

Maternal obesity is a well-known risk factor for developing premature obesity, metabolic syndrome, cardiovascular disease and type 2 diabetes in the progeny. The development of white adipose tissue is a dynamic process that starts during prenatal life: fat depots laid down in utero are associated with the proportion of fat in children later on. How early this programming takes place is still unknown. However, recent evidence shows that mesenchymal stem cells (MSC), the embryonic adipocyte precursor cells, show signatures of the early setting of an adipogenic committed phenotype when exposed to maternal obesity. This review aims to present current findings on the cellular adaptations of MSCs from the offspring of women with obesity and how the metabolic environment of MSCs could affect the early commitment towards adipocytes. In conclusion, maternal obesity can induce early programming of fetal adipose tissue by conditioning MSCs. These cells have higher expression of adipogenic markers, altered insulin signalling and mitochondrial performance, compared to MSCs of neonates from lean pregnancies. Fetal MSCs imprinting by maternal obesity could help explain the increased risk of childhood obesity and development of further noncommunicable diseases.

Exposome and foetoplacental vascular dysfunction in gestational diabetes mellitus.

A balanced communication between the mother, placenta and foetus is crucial to reach a successful pregnancy. Several windows of exposure to environmental toxins are present during pregnancy. When the women metabolic status is affected by a disease or environmental toxin, the foetus is impacted and may result in altered development and growth. Gestational diabetes mellitus (GDM) is a disease of pregnancy characterised by abnormal glucose metabolism affecting the mother and foetus. This disease of pregnancy associates with postnatal consequences for the child and the mother. The whole endogenous and exogenous environmental factors is defined as the exposome. Endogenous insults conform to the endo-exposome, and disruptors contained in the immediate environment are the ecto-exposome. Some components of the endo-exposome, such as Selenium, vitamins D and B12, adenosine, and a high-fat diet, and ecto-exposome, such as the heavy metals Arsenic, Mercury, Lead and Copper, and per- and polyfluoroakyl substances, result in adverse pregnancies, including an elevated risk of GDM or gestational diabesity. The impact of the exposome on the human placenta's vascular physiology and function in GDM and gestational diabesity is reviewed.

Maternal Obesity Is Associated With Higher Cord Blood Adipokines in Offspring Most Notably in Females.

BACKGROUND: Deleterious long-term effects in the offspring from women with pregravid obesity have been described; however, the evidence supporting early metabolic and inflammatory markers in the offspring at birth and gender differences are conflicting. OBJECTIVE: The present study aimed to compare cord blood adipokines and cytokines concentrations and anthropometric characteristics of the offspring of women with maternal obesity (MO) and normal-weight mothers (NWM). Also, maternal and neonatal variables on the association of maternal body mass index (BMI) with cord blood adipokines were evaluated. METHODS: A cross-sectional analysis of a subsample of mother-child dyads participating in a cohort study (n = 221) was assessed. Anthropometrics, cord blood adipokines (leptin and adiponectin) and cytokines (interleukin [IL]-1ß, IL-4, IL-10, IL-12 p40, IL-12p70, IL-13, and tumor necrosis factor α) concentrations in the offspring of normal-weight women (BMI >18.5 and <24.9 kg/m2) and women with pregravid obesity (BMI > 30 kg/m2) without comorbidities was performed. RESULTS: Offspring from mothers with obesity had higher birth weight, a higher proportion of large for gestational age, higher ponderal index, and heavier placentae than offspring from normal-weight mothers (P < 0.05). Within the offspring from women with obesity, males had significantly higher weight, length, the proportion of large-for-gestational-age newborns, higher weight for length ratio. Males had more efficient placentas than females (P < 0.05). Higher adiponectin and leptin in both sexes and higher leptin in female offspring of mothers with obesity after adjusting for birth size (P < 0.05) were found. Higher IL-12p40 in the offspring of women with MO with no other differences in other cytokines among groups were evidenced. CONCLUSIONS: Maternal obesity associates with a higher concentration of adiponectin and leptin in their offspring at birth. There is a relevant effect on anthropometrics in male offspring and on leptin in female newborn. Further studies need to evaluate the extension of these effects in postnatal life. TRAIL IDENTIFICATION NUMBER: NCT02903134.

Gestational diabesity and foetoplacental vascular dysfunction.

Gestational diabetes mellitus (GDM) shows a deficiency in the metabolism of D-glucose and other nutrients, thereby negatively affecting the foetoplacental vascular endothelium. Maternal hyperglycaemia and hyperinsulinemia play an important role in the aetiology of GDM. A combination of these and other factors predisposes women to developing GDM with pre-pregnancy normal weight, viz. classic GDM. However, women with GDM and prepregnancy obesity (gestational diabesity, GDty) or overweight (GDMow) show a different metabolic status than women with classic GDM. GDty and GDMow are associated with altered l-arginine/nitric oxide and insulin/adenosine axis signalling in the human foetoplacental microvascular and macrovascular endothelium. These alterations differ from those observed in classic GDM. Here, we have reviewed the consequences of GDty and GDMow in the modulation of foetoplacental endothelial cell function, highlighting studies describing the modulation of intracellular pH homeostasis and the potential implications of NO generation and adenosine signalling in GDty-associated foetal vascular insulin resistance. Moreover, with an increase in the rate of obesity in women of childbearing age worldwide, the prevalence of GDty is expected to increase in the next decades. Therefore, we emphasize that women with GDty and GDMow should be characterized with a different metabolic state from that of women with classic GDM to develop a more specific therapeutic approach for protecting the mother and foetus.

Expression of teneurins is associated with tumor differentiation and patient survival in ovarian cancer.

Teneurins are a family of highly conserved pair-rule proteins involved in morphogenesis and development of the central nervous system. Their function in adult tissues and in disease is largely unknown. Recent evidence suggests a role for dysregulated expression of Teneurins in human tumors, but systematic investigations are missing. Here, we investigated Teneurin-2 and Teneurin-4 expression in various cancer cell lines and in ovarian tumor tissues. Teneurin-2 and Teneurin-4 were expressed in most of the breast cancer cell lines tested. Teneurin-4 was also detected in ovarian cancer cell lines, and throughout ovarian tumors and normal ovary tissue. Ovarian tumors with low Teneurin-4 expression showed less differentiated phenotypes and these patients had shorter mean overall survival. Similarly, Teneurin-2 expression correlated with overall survival as well, especially in patients with serous tumors. In the various cell lines, 5-Aza-cytidine-induced changes in DNA methylation did not alter expression of Teneurin-2 and Teneurin-4, despite the existence of predicted CpG islands in both genes. Interestingly, however, we found evidence for the control of Teneurin-2 expression by the oncogenic growth factor FGF8. Furthermore, we identified multiple transcript splicing variants for Teneurin-2 and Teneurin-4, indicating complex gene expression patterns in malignant cells. Finally, downregulation of Teneurin-4 expression using siRNA caused a cell-type dependent increase in proliferation and resistance to cisplatin. Altogether, our data suggest that low Teneurin-4 expression provides a growth advantage to cancer cells and marks an undifferentiated state characterized by increased drug resistance and clinical aggressiveness. We conclude that Teneurin-2 and Teneurin-4 expression levels could be of prognostic value in ovarian cancer.

IL-10 expression in macrophages from neonates born from obese mothers is suppressed by IL-4 and LPS/INFγ.

Obese women offspring have a higher risk of developing chronic diseases associated with an altered immune function. We aim to determine, in neonatal monocyte-derived macrophages, whether maternal obesity is associated with an altered expression and DNA methylation of pro- and anti-inflammatory genes, along with a higher pro-inflammatory response. Cord blood from newborns of obese (Ob) and lean (control) women were obtained at delivery. Monocytes were isolated and differentiated into macrophages, in which M1 (LPS/IFNγ) and M2 (IL-4) polarization were assayed. The mRNA levels for TNFα, IL-1ß, IL-12A, IL-12B, IL-10, and IL-4R were quantified by qPCR and the DNA methylation of candidate genes determined by pyrosequencing. RESULTS: Ob-monocytes had decreased levels of mRNA for pro-inflammatory cytokines IL-1ß, IL-10, and IL-12B compared with controls. Conversely, Ob-macrophages showed increased levels of mRNA for TNFα, IL-4R, and IL-10 compared with controls. M1 response was comparable between both groups, characterized by an important induction of TNFα and IL-1ß. In response to an M2 stimulus, control macrophages showed a decreased expression of inflammatory mediators while Ob-macrophages had an additional suppression of the anti-inflammatory mediator IL-10. Changes in IL-1ß (monocytes) and IL-10 (macrophages) in Ob-monocytes were paralleled by changes in their promoter DNA methylation in fetal monocytes. These results suggest that monocyte-derived macrophages from obese newborns show a basal anti-inflammatory phenotype with an unbalanced response to M1 and M2 polarization stimuli. The presence of changes in DNA methylation of key inflammatory genes in neonatal monocytes suggests an intrauterine programing of immune function by maternal obesity.

N-Acetylcysteine, a glutathione precursor, reverts vascular dysfunction and endothelial epigenetic programming in intrauterine growth restricted guinea pigs.

KEY POINTS: Intrauterine growth restriction (IUGR) is associated with vascular dysfunction, oxidative stress and signs of endothelial epigenetic programming of the umbilical vessels. There is no evidence that this epigenetic programming is occurring on systemic fetal arteries. In IUGR guinea pigs we studied the functional and epigenetic programming of endothelial nitric oxide synthase (eNOS) (Nos3 gene) in umbilical and systemic fetal arteries, addressing the role of oxidative stress in this process by maternal treatment with N-acetylcysteine (NAC) during the second half of gestation. The present study suggests that IUGR endothelial cells have common molecular markers of programming in umbilical and systemic arteries. Notably, maternal treatment with NAC restores fetal growth by increasing placental efficiency and reverting the functional and epigenetic programming of eNOS in arterial endothelium in IUGR guinea pigs. ABSTRACT: In humans, intrauterine growth restriction (IUGR) is associated with vascular dysfunction, oxidative stress and signs of endothelial programming in umbilical vessels. We aimed to determine the effects of maternal antioxidant treatment with N-acetylcysteine (NAC) on fetal endothelial function and endothelial nitric oxide synthase (eNOS) programming in IUGR guinea pigs. IUGR was induced by implanting ameroid constrictors on uterine arteries of pregnant guinea pigs at mid gestation, half of the sows receiving NAC in the drinking water (from day 34 until term). Fetal biometry and placental vascular resistance were followed by ultrasound throughout gestation. At term, umbilical arteries and fetal aortae were isolated to assess endothelial function by wire-myography. Primary cultures of endothelial cells (ECs) from fetal aorta, femoral and umbilical arteries were used to determine eNOS mRNA levels by quantitative PCR and analyse DNA methylation in the Nos3 promoter by pyrosequencing. Doppler ultrasound measurements showed that NAC reduced placental vascular resistance in IUGR (P < 0.05) and recovered fetal weight (P < 0.05), increasing fetal-to-placental ratio at term (∼40%) (P < 0.001). In IUGR, NAC treatment restored eNOS-dependent relaxation in aorta and umbilical arteries (P < 0.05), normalizing eNOS mRNA levels in EC fetal and umbilical arteries (P < 0.05). IUGR-derived ECs had a decreased DNA methylation (∼30%) at CpG -170 (from the transcription start site) and this epigenetic signature was absent in NAC-treated fetuses (P < 0.001). These data show that IUGR-ECs have common molecular markers of eNOS programming in umbilical and systemic arteries and this effect is prevented by maternal treatment with antioxidants.

[Epigenetics and obesity]. / Epigenética y obesidad.

Current evidence supports the notion that exposure to various environmental conditions in early life may induce permanent changes in the epigenome that persist throughout the life-course. This article focuses on early changes associated with obesity in adult life. A review is presented on the factors that induce changes in whole genome (DNA) methylation in early life that are associated with adult onset obesity and related disorders. In contrast, reversal of epigenetic changes associated with weight loss in obese subjects has not been demonstrated. This contrasts with well-established associations found between obesity related DNA methylation patterns at birth and adult onset obesity and diabetes. Epigenetic markers may serve to screen indivuals at risk for obesity and assess the effects of interventions in early life that may delay or prevent obesity in early life. This might contribute to lower the obesity-related burden of death and disability at the population level. The available evidence indicates that epigenetic marks are in fact modifiable, based on modifications in the intrauterine environment and changes in food intake, physical activity and dietary patterns patterns during pregnancy and early years of adult life. This offers the opportunity to intervene before conception, during pregnancy, infancy, childhood, and also in later life. There must be documentation on the best preventive actions in terms of diet and physical activity that will modify or revert the adverse epigenetic markers, thus preventing obesity and diabetes in suceptible individuals and populations.

Epigenética y obesidad / Epigenetics and obesity

La evidencia indica que la exposición a diversas condiciones ambientales en etapas tempranas de la vida puede inducir alteraciones persistentes en el epigenoma. Los estudios epigenómicos en sujetos obesos han permitido evaluar el papel de los mecanismos epigenéticos en el origen y desarrollo de la obesidad. La presente revisión aborda estudios que dan cuenta de la asociación entre la obesidad y metilación global del genoma (ADN), analizando el potencial impacto de intervenciones previas y posteriores al nacimiento que afectan la metilación del ADN y la obesidad en etapas más avanzadas de la vida. Estudios realizados principalmente en leucocitos, han logrado identificar sitios del ADN diferencialmente metilados asociados con obesidad. Estudios hasta la fecha no han demostrado que dichos cambios en metilación sean revertidos luego de bajar de peso. Esto contrasta con resultados iniciales en este campo, que sugieren que existirían marcadores epigenéticos presentes desde el nacimiento que permitirían definir el riesgo de obesidad durante el curso de la vida. La evidencia actual sugiere que algunas marcas epigenéticas son modificables, basándonos en la exposición en la vida intrauterina y también por los hábitos dietarios y de actividad fisica durante las etapas del crecimiento y en la adultez. Esto sugiere que existe la oportunidad de intervenir durante la gestación o en la vida posnatal temprana, que modificaría los perfiles epigenéticos desfavorables e idealmente contribuiría a prevenir la obesidad en los sujetos o poblaciones susceptibles.

Current evidence supports the notion that exposure to various environmental conditions in early life may induce permanent changes in the epigenome that persist throughout the life-course. This article focuses on early changes associated with obesity in adult life. A review is presented on the factors that induce changes in whole genome (DNA) methylation in early life that are associated with adult onset obesity and related disorders. In contrast, reversal of epigenetic changes associated with weight loss in obese subjects has not been demonstrated. This contrasts with well-established associations found between obesity related DNA methylation patterns at birth and adult onset obesity and diabetes. Epigenetic markers may serve to screen indivuals at risk for obesity and assess the effects of interventions in early life that may delay or prevent obesity in early life. This might contribute to lower the obesity-related burden of death and disability at the population level. The available evidence indicates that epigenetic marks are in fact modifiable, based on modifications in the intrauterine environment and changes in food intake, physical activity and dietary patterns patterns during pregnancy and early years of adult life. This offers the opportunity to intervene before conception, during pregnancy, infancy, childhood, and also in later life. There must be documentation on the best preventive actions in terms of diet and physical activity that will modify or revert the adverse epigenetic markers, thus preventing obesity and diabetes in suceptible individuals and populations.

[Epigenetics in allergic diseases and asthma]. / Epigenética en enfermedades alérgicas y asma.

Allergic diseases and asthma are the result of complex interactions between genetic predisposition and environmental factors. Asthma is one of the most prevalent chronic disease among children. In this article we review some environmental factors like: allergen exposition, tobacco, bacteria, microbial components, diet, obesity and stress, which influences during intrauterine and infancy life in the epigenetic regulation of asthma and allergic diseases. The review has been done in three models: in-vitro, animal and human.

Epigenética en enfermedades alérgicas y asma / Epigenetics in allergic diseases and asthma

Las enfermedades alérgicas y el asma son el resultado de complejas interacciones entre la predisposición genética y factores ambientales. El asma es una de las enfermedades crónicas más prevalentes en niños. En este artículo se revisan algunos factores ambientales como la exposición a alérgenos, tabaco, bacterias, componentes microbianos, dieta, obesidad y estrés, que intervienen durante la vida intrauterina y la infancia en la regulación epigenética de las enfermedades alérgicas y el asma. La revisión se realiza en tres tipos de modelos: in-vitro, animales y humanos.

Allergic diseases and asthma are the result of complex interactions between genetic predisposition and environmental factors. Asthma is one of the most prevalent chronic disease among children. In this article we review some environmental factors like: allergen exposition, tobacco, bacteria, microbial components, diet, obesity and stress, which influences during intrauterine and infancy life in the epigenetic regulation of asthma and allergic diseases. The review has been done in three models: in-vitro, animal and human.

[General concepts of epigenetics: Projections in paediatrics]. / Conceptos generales de epigenética: proyecciones en pediatría.

Current evidence supports the notion that alterations in intrauterine growth and during the first years of life have a substantial effect on the risk for the development of chronic disease, which in some cases is even higher than those due to genetic factors. The persistence and reproducibility of the phenotypes associated with altered early development suggest the participation of mechanisms that would record environmental cues, generating a cellular reprogramming (i.e., epigenetic mechanisms). This review is an introduction to a series of five articles focused on the participation of epigenetic mechanisms in the development of highly prevalent chronic diseases (i.e., cardiovascular, metabolic, asthma/allergies and cancer) and their origins in the foetal and neonatal period. This series of articles aims to show the state of the art in this research area and present the upcoming clues and challenges, in which paediatricians have a prominent role, developing strategies for the prevention, early detection and follow-up.

Conceptos generales de epigenética: proyecciones en pediatría / General concepts of epigenetics: projections in paediatrics

La asociación entre factores ambientales presentes durante el desarrollo embrionario/fetal y enfermedades que puedan presentarse durante la vida representa un campo de creciente interés. En este contexto la evidencia actual apoya fuertemente que alteraciones en el crecimiento intrauterino y durante los primeros años de vida presentan una fuerte influencia en el riesgo de padecer enfermedades crónicas que en muchos casos pudiera ser mayor que la carga genética del paciente. La persistencia y reproducibilidad de los fenotipos asociados a alteraciones en el desarrollo temprano sugieren la participación de mecanismos moleculares que registran dichas modificaciones (i.e. mecanismos epigenéticos) generando una «reprogramación¼ celular y fisiológica. Esta revisión es la introducción a una serie de 5 artículos en torno a la participación de los mecanismos epigenéticos en el desarrollo de enfermedades crónicas (i.e. cardiovasculares, metabólicas, asma/alergias y cáncer) y su relación con el origen de dichas enfermedades en etapas tempranas del desarrollo. El objetivo de esta serie es mostrar el estado actual de esta área de la investigación y presentar los desafíos e interrogantes futuros en los cuales la pediatría tiene un papel preponderante, desarrollando estrategias para la prevención, detección precoz y seguimiento.

Current evidence supports the notion that alterations in intrauterine growth and during the first years of life have a substantial effect on the risk for the development of chronic disease, which in some cases is even higher than those due to genetic factors. The persistence and reproducibility of the phenotypes associated with altered early development suggest the participation of mechanisms that would record environmental cues, generating a cellular reprogramming (i.e. epigenetic mechanisms). This review is an introduction to a series of five articles focused on the participation of epigenetic mechanisms in the development of highly prevalent chronic diseases (i.e. cardiovascular, metabolic, asthma/allergies and cancer) and their origins in the foetal and neonatal period. This series of articles aims to show the state of the art in this research area and present the upcoming clues and challenges, in which paediatricians have a prominent role, developing strategies for the prevention, early detection and follow-up.

Assessment of in vivo fetal growth and placental vascular function in a novel intrauterine growth restriction model of progressive uterine artery occlusion in guinea pigs.

Intra-uterine growth restriction (IUGR) is associated with short and long-term metabolic and cardiovascular alterations. Mice and rats have been extensively used to study the effects of IUGR, but there are notable differences in fetal and placental physiology relative to those of humans that argue for alternative animal models. This study proposes that gradual occlusion of uterine arteries from mid-gestation in pregnant guinea pigs produces a novel model to better assess human IUGR. Fetal biometry and in vivo placental vascular function were followed by sonography and Doppler of control pregnant guinea pigs and sows submitted to surgical placement of ameroid constrictors in both uterine arteries (IUGR) at mid-gestation (35 days). The ameroid constrictors induced a reduction in the fetal abdominal circumference growth rate (0.205 cm day(-1) ) compared to control (0.241 cm day(-1) , P < 0.001) without affecting biparietal diameter growth. Umbilical artery pulsatility and resistance indexes at 10 and 20 days after surgery were significantly higher in IUGR animals than controls (P < 0.01). These effects were associated with a decrease in the relative luminal area of placental chorionic arteries (21.3 ± 2.2% vs. 33.2 ± 2.7%, P < 0.01) in IUGR sows at near term. Uterine artery intervention reduced fetal (∼30%), placental (∼20%) and liver (∼50%) weights (P < 0.05), with an increased brain to liver ratio (P < 0.001) relative to the control group. These data demonstrate that the ameroid constrictor implantations in uterine arteries in pregnant guinea pigs lead to placental vascular dysfunction and altered fetal growth that induces asymmetric IUGR.

Arginase-2 is cooperatively up-regulated by nitric oxide and histone deacetylase inhibition in human umbilical artery endothelial cells.

Arginase-2 counteracts endothelial nitric oxide synthase (eNOS) activity in human endothelium, and its expression is negatively controlled by histone deacetylase (HDAC2). Conversely NO inhibits HDAC and previous studies suggest that arginase-2 is up-regulated by NO. We studied whether NO regulates arginase-2 expression in umbilical artery endothelial cells (HUAEC) increasing ARG2 promoter accessibility. HUAEC exposed to NOC-18 (NO donor, 1-100 µM, 0-24 h) showed an increase in arginase-2 but a decrease in eNOS mRNA levels in a time-dependent manner, with a maximal effect at 100 µM (24 h). Conversely NOS inhibition with L-NAME (100 µM) reduced arginase-2 mRNA and protein levels, an effect reverted by co-incubation with NOC-18. Treatment with TSA paralleled the effects of NO on arginase-2 and eNOS at mRNA and protein levels, with maximal effect at 10 µM. Co-incubation of NOC-18 (100 µM) with a sub-maximal concentration of TSA (1 µM) potentiated the increase in arginase-2 mRNA levels, whilst L-NAME prevented TSA-dependent arginase-2 induction. The effects on arginase-2 mRNA were paralleled by changes in chromatin accessibility, as well as increased levels of H3K9 and H4K12 acetylation, at ARG2 proximal (-579 to -367 and -280 to -73 bp from TSS) and core (-121 to +126 bp from TSS) promoter. Finally NO-dependent arginase-2 induction was prevented by pre-incubation for 10 min with the cysteine blocker MMTS (10 mM). These data showed for the first time that NO up-regulates arginase-2 expression in primary cultured human endothelial cells by an epigenetic-mediated mechanism increasing ARG2 promoter accessibility suggesting a negative regulatory loop for eNOS activity.

Effectiveness of a normative nutrition intervention (diet, physical activity and breastfeeding) on maternal nutrition and offspring growth: the Chilean maternal and infant nutrition cohort study (CHiMINCs).

BACKGROUND: Maternal obesity before and during pregnancy predicts maternal and infant risks of obesity and its associated metabolic conditions. Dietary and physical activity recommendations during pregnancy as well as weight monitoring are currently available in the Chilean primary health care system. However some of these recommendations are not updated and most of them are poorly implemented. We seek to assess the effectiveness of an intervention that enhances the implementation of updated nutrition health care standards (diet, physical activity, and breastfeeding promotion) during pregnancy on maternal weight gain and infant growth. DESIGN & SETTING: Cluster randomized controlled trial. The cluster units will be 12 primary health care centers from two counties (La Florida and Puente Alto) from the South-East Area of Santiago randomly allocated to: 1) enhanced nutrition health care standards (intervention group) or 2) routine care (control group). PARTICIPANTS: Women seeking prenatal care before 15 weeks of gestation, residing within a catchment area of selected health centers, and who express that they are not planning to change residence will be invited to participate in the study. Pregnant women classified as high risk according to the Chilean norms (i.e age <16 or >40 years, multiple gestation, pre-gestational medical conditions, previous pregnancy-related issues) and/or underweight will be excluded. INTERVENTION: Pregnant women who attend intervened health care centers starting at their first prenatal visit will receive advice regarding optimal weight gain during pregnancy and diet and physical activity counseling-support. Pregnant women who attend control health clinics will receive routine antenatal care according to national guidelines. We plan to recruit 200 women in each health center. Assuming a 20% loss to follow up, we expect to include 960 women per arm. MAIN OUTCOME MEASURES: 1) Achievement of adequate weight gain based on IOM 2009 recommendations and adequate glycaemic control at 24-28 weeks of pregnancy according to ADA 2011, and 2) healthy infant growth during the first year of age based on WHO standards. DISCUSSION: We expect that the intervention will benefit the participants in achieving adequate weight gain & metabolic control during pregnancy as well as adequate infant growth as a result of an increased impact of standard nutrition and health care practices. Gathered information should contribute to a better understanding of how to develop effective interventions to halt the maternal obesity epidemic and its associated co-morbidities in the Chilean population. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT01916603.

5'-ectonucleotidase mediates multiple-drug resistance in glioblastoma multiforme cells.

Glioblastoma multiforme (GBM) cells are characterised by their extreme chemoresistance. The activity of multiple-drug resistance (MDR) transporters that extrude antitumor drugs from cells plays the most important role in this phenomenon. To date, the mechanism controlling the expression and activity of MDR transporters is poorly understood. Activity of the enzyme ecto-5'-nucleotidase (CD73) in tumor cells, which hydrolyses AMP to adenosine, has been linked to immunosuppression and prometastatic effects in breast cancer and to the proliferation of glioma cells. In this study, we identify a high expression of CD73 in surgically resected samples of human GBM. In primary cultures of GBM, inhibition of CD73 activity or knocking down its expression by siRNA reversed the MDR phenotype and cell viability was decreased up to 60% on exposure to the antitumoral drug vincristine. This GBM chemosensitization was caused by a decrease in the expression and activity of the multiple drug associated protein 1 (Mrp1), the most important transporter conferring multiple drug resistance in these cells. Using pharmacological modulators, we have recognized the adenosine A(3) receptor subtype in mediation of the chemoresistant phenotype in these cells. In conclusion, we have determined that the activity of CD73 to trigger adenosine signaling sustains chemoresistant phenotype in GBM cells.

Gestational diabetes reduces adenosine transport in human placental microvascular endothelium, an effect reversed by insulin.

Gestational diabetes mellitus (GDM) courses with increased fetal plasma adenosine concentration and reduced adenosine transport in placental macrovascular endothelium. Since insulin modulates human equilibrative nucleoside transporters (hENTs) expression/activity, we hypothesize that GDM will alter hENT2-mediated transport in human placental microvascular endothelium (hPMEC), and that insulin will restore GDM to a normal phenotype involving insulin receptors A (IR-A) and B (IR-B). GDM effect on hENTs expression and transport activity, and IR-A/IR-B expression and associated cell signalling cascades (p42/44 mitogen-activated protein kinases (p42/44(mapk)) and Akt) role in hPMEC primary cultures was assayed. GDM associates with elevated umbilical whole and vein, but not arteries blood adenosine, and reduced hENTs adenosine transport and expression. IR-A/IR-B mRNA expression and p42/44(mapk)/Akt ratios ('metabolic phenotype') were lower in GDM. Insulin reversed GDM-reduced hENT2 expression/activity, IR-A/IR-B mRNA expression and p42/44(mapk)/Akt ratios to normal pregnancies ('mitogenic phenotype'). It is suggested that insulin effects required IR-A and IR-B expression leading to differential modulation of signalling pathways restoring GDM-metabolic to a normal-mitogenic like phenotype. Insulin could be acting as protecting factor for placental microvascular endothelial dysfunction in GDM.

Fetoplacental vascular endothelial dysfunction as an early phenomenon in the programming of human adult diseases in subjects born from gestational diabetes mellitus or obesity in pregnancy.

Gestational diabetes mellitus (GDM) and obesity in pregnancy (OP) are pathological conditions associated with placenta vascular dysfunction coursing with metabolic changes at the fetoplacental microvascular and macrovascular endothelium. These alterations are seen as abnormal expression and activity of the cationic amino acid transporters and endothelial nitric oxide synthase isoform, that is, the "endothelial L-arginine/nitric oxide signalling pathway." Several studies suggest that the endogenous nucleoside adenosine along with insulin, and potentially arginases, are factors involved in GDM-, but much less information regards their role in OP-associated placental vascular alterations. There is convincing evidence that GDM and OP prone placental endothelium to an "altered metabolic state" leading to fetal programming evidenced at birth, a phenomenon associated with future development of chronic diseases. In this paper it is suggested that this pathological state could be considered as a metabolic marker that could predict occurrence of diseases in adulthood, such as cardiovascular disease, obesity, diabetes mellitus (including gestational diabetes), and metabolic syndrome.