165. PLASTICITY IN IMPRINTING OF BOVINE IGF2R CORRELATES WITH TOTAL EXPRESSION LEVELS IN FETAL TISSUES

2009 ◽  
Vol 21 (9) ◽  
pp. 83
Author(s):  
Y. Liu ◽  
C. Fitzsimmons ◽  
Z. Kruk ◽  
M. Deland ◽  
S. Maddocks ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Fetal Liver ◽  
Fetal Brain ◽  
Monoallelic Expression ◽  
Additional Species ◽  
Biallelic Expression ◽  
Expression Levels ◽  
Fetal Tissues ◽  
Polymorphic Microsatellite ◽  
Fine Tune

The multifunctional insulin-like growth factor 2 receptor (IGF2R) facilitates endocytosis and subsequent clearance or activation of a variety of ligands involved in cell growth and motility. Thus, the IGF2R gene has a major role in embryonic development and fetal growth. Murine Igf2r is subject to genomic imprinting and maternally expressed in peripheral fetal tissues. However, data on imprinting of IGF2R in human is still controversial with biallelic expression, partial imprinting, and monoallelic expression reported for fetal tissues [1, 2, 3]. Data from additional species may help to understand fetal IGF2R expression. The bovine is similar to human in that it is outbred and monotocous. We have analysed bovine Day 153 fetuses (55% to term, n=40) with Bos primigenius indicus and B. p. taurus genetics to determine the imprinting status of IGF2R in fetal brain, liver and skeletal muscle. Sequencing of PCR amplicons from IGF2R exon 48 revealed a polymorphic microsatellite and 14 SNPs. These were used to identify 15 heterozygous fetuses informative for imprinting analysis. We found biallelic expression of IGF2R in fetal brain and predominantly maternal expression in fetal liver and skeletal muscle. However, we observed considerable plasticity in imprinting in liver and skeletal muscle with paternal expression levels of 7%-21% and 4%-21%, respectively. Fetal liver samples with B. p. indicus maternal genetics showed significantly higher mean paternal expression levels than those with B. p. taurus maternal genetics (P<0.05). Real-time qPCR showed a significant relationship between imprinting and total IGF2R expression level within both tissues (P<0.05). Our data indicate plasticity in imprinting of IGF2R that could fine tune expression levels in fetal tissues.

scholarly journals Somatotroph Tumors and the Epigenetic Status of the GNAS Locus

2021 ◽  
Vol 22 (14) ◽  
pp. 7570
Author(s):  
Pauline Romanet ◽  
Justine Galluso ◽  
Peter Kamenicky ◽  
Mirella Hage ◽  
Marily Theodoropoulou ◽  
...  
Keyword(s):  
Genomic Analysis ◽  
Somatostatin Analogues ◽  
Differentially Methylated Region ◽  
Monoallelic Expression ◽  
Lower Sensitivity ◽  
Biallelic Expression ◽  
Expression Levels ◽  
Methylation Index ◽  
Significant Difference ◽  
Gsp Oncogene

Background: Forty percent of somatotroph tumors harbor recurrent activating GNAS mutations, historically called the gsp oncogene. In gsp-negative somatotroph tumors, GNAS expression itself is highly variable; those with GNAS overexpression most resemble phenotypically those carrying the gsp oncogene. GNAS is monoallelically expressed in the normal pituitary due to methylation-based imprinting. We hypothesize that changes in GNAS imprinting of gsp-negative tumors affect GNAS expression levels and tumorigenesis. Methods: We characterized the GNAS locus in two independent somatotroph tumor cohorts: one of 23 tumors previously published (PMID: 31883967) and classified by pan-genomic analysis, and a second with 82 tumors. Results: Multi-omics analysis of the first cohort identified a significant difference between gsp-negative and gsp-positive tumors in the methylation index at the known differentially methylated region (DMR) of the GNAS A/B transcript promoter, which was confirmed in the larger series of 82 tumors. GNAS allelic expression was analyzed using a polymorphic Fok1 cleavage site in 32 heterozygous gsp-negative tumors. GNAS expression was significantly reduced in the 14 tumors with relaxed GNAS imprinting and biallelic expression, compared to 18 tumors with monoallelic expression. Tumors with relaxed GNAS imprinting showed significantly lower SSTR2 and AIP expression levels. Conclusion: Altered A/B DMR methylation was found exclusively in gsp-negative somatotroph tumors. 43% of gsp-negative tumors showed GNAS imprinting relaxation, which correlated with lower GNAS, SSTR2 and AIP expression, indicating lower sensitivity to somatostatin analogues and potentially aggressive behavior.

scholarly journals DHA supplementation during pregnancy as phospholipids or TAG produces different placental uptake but similar fetal brain accretion in neonatal piglets

2017 ◽  
Vol 118 (11) ◽  
pp. 981-988 ◽  
Author(s):  
Antonio Gázquez ◽  
María Ruíz-Palacios ◽  
Elvira Larqué
Keyword(s):  
Fetal Liver ◽  
Fetal Brain ◽  
Placental Tissue ◽  
Egg Yolk ◽  
Major Facilitator Superfamily ◽  
Total Lipids ◽  
Fetal Plasma ◽  
Fetal Tissues ◽  
Chain Pufa ◽  
Total Fatty Acids

AbstractThe great variety of n-3 long-chain PUFA sources raises the question of the most adequate for using as a DHA supplement during pregnancy. Placental and fetal availability of different DHA sources remains unclear. We investigated DHA availability in maternal lipoproteins, placenta and fetal tissues in pregnant sows fed DHA as phospholipid (PL) or TAG to identify the best DHA source during this period. Pregnant Iberian sows were fed diets containing 0·8 % DHA of total fatty acids as PL from egg yolk or TAG from algae oil during the last third of gestation (40 d). Maternal tissues, placentas and fetal tissues were obtained at delivery and DHA quantified by GC. Major Facilitator Superfamily Domain Containing 2a (MFSD2a) carrier expression was analysed in both placenta and fetal brain by Western blotting. Sows fed the DHA–PL diet showed higher DHA incorporation in plasma LDL but not in plasma total lipids. No differences were found in DHA content between groups in maternal liver, adipose tissue or brain. Placental tissue incorporated more DHA in both total lipids and PL fraction in sows fed DHA–PL. However, this did not lead to an enhanced DHA accretion either in fetal plasma, fetal liver or fetal brain. MFSD2a expression was similar between both experimental groups. Maternal DHA supplementation during pregnancy in sow either as PL or TAG produces similar DHA accretion in fetal tissues but not in placenta. Both fat sources are equally available for fetal brain.

scholarly journals An enriched biosignature of gut microbiota-dependent metabolites characterizes maternal plasma in a mouse model of fetal alcohol spectrum disorder

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manjot S. Virdee ◽  
Nipun Saini ◽  
Colin D. Kay ◽  
Andrew P. Neilson ◽  
Sze Ting Cecilia Kwan ◽  
...  
Keyword(s):  
Phenolic Acids ◽  
Fetal Liver ◽  
Prenatal Alcohol Exposure ◽  
Fetal Brain ◽  
Principal Component ◽  
Alcohol Exposure ◽  
Maternal Plasma ◽  
Cognitive Disability ◽  
Fetal Alcohol ◽  
Network Analyses

AbstractPrenatal alcohol exposure (PAE) causes permanent cognitive disability. The enteric microbiome generates microbial-dependent products (MDPs) that may contribute to disorders including autism, depression, and anxiety; it is unknown whether similar alterations occur in PAE. Using a mouse PAE model, we performed untargeted metabolome analyses upon the maternal–fetal dyad at gestational day 17.5. Hierarchical clustering by principal component analysis and Pearson’s correlation of maternal plasma (813 metabolites) both identified MDPs as significant predictors for PAE. The majority were phenolic acids enriched in PAE. Correlational network analyses revealed that alcohol altered plasma MDP-metabolite relationships, and alcohol-exposed maternal plasma was characterized by a subnetwork dominated by phenolic acids. Twenty-nine MDPs were detected in fetal liver and sixteen in fetal brain, where their impact is unknown. Several of these, including 4-ethylphenylsulfate, oxindole, indolepropionate, p-cresol sulfate, catechol sulfate, and salicylate, are implicated in other neurological disorders. We conclude that MDPs constitute a characteristic biosignature that distinguishes PAE. These MDPs are abundant in human plasma, where they influence physiology and disease. Their altered abundance here may reflect alcohol’s known effects on microbiota composition and gut permeability. We propose that the maternal microbiome and its MDPs are a previously unrecognized influence upon the pathologies that typify PAE.

scholarly journals Limited capacity for glucose oxidation in fetal sheep with intrauterine growth restriction

2015 ◽  
Vol 309 (8) ◽  
pp. R920-R928 ◽  
Author(s):  
Laura D. Brown ◽  
Paul J. Rozance ◽  
Jennifer L. Bruce ◽  
Jacob E. Friedman ◽  
William W. Hay ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Mrna Expression ◽  
Glucose Oxidation ◽  
Fetal Liver ◽  
Lactate Production ◽  
Glucose Production ◽  
Limited Capacity ◽  
Fetal Sheep ◽  
Intrauterine Growth ◽  
Insulin Clamp

Intrauterine growth-restricted (IUGR) fetal sheep, produced by placental insufficiency, have lower oxygen concentrations, higher lactate concentrations, and increased hepatic glucose production that is resistant to suppression by insulin. We hypothesized that increased lactate production in the IUGR fetus results from reduced glucose oxidation, during basal and maximal insulin-stimulated conditions, and is used to support glucose production. To test this, studies were performed in late-gestation control (CON) and IUGR fetal sheep under basal and hyperinsulinemic-clamp conditions. The basal glucose oxidation rate was similar and increased by 30–40% during insulin clamp in CON and IUGR fetuses ( P < 0.005). However, the fraction of glucose oxidized was 15% lower in IUGR fetuses during basal and insulin-clamp periods ( P = 0.05). IUGR fetuses also had four-fold higher lactate concentrations ( P < 0.001) and lower lactate uptake rates ( P < 0.05). In IUGR fetal muscle and liver, mRNA expression of pyruvate dehydrogenase kinase ( PDK4), an inhibitor of glucose oxidation, was increased over fourfold. In IUGR fetal liver, but not skeletal muscle, mRNA expression of lactate dehydrogenase A ( LDHA) was increased nearly fivefold. Hepatic expression of the gluconeogenic genes, phosphoenolpyruvate carboxykinase ( PCK)1, and PCK2, was correlated with expression of PDK4 and LDHA. Collectively, these in vivo and tissue data support limited capacity for glucose oxidation in the IUGR fetus via increased PDK4 in skeletal muscle and liver. We speculate that lactate production also is increased, which may supply carbon for glucose production in the IUGR fetal liver.

scholarly journals Nanopolystyrene translocation and fetal deposition after acute lung exposure during late-stage pregnancy

2020 ◽  
Author(s):  
Sara B Fournier ◽  
Jeanine N D’Errico ◽  
Derek S Adler ◽  
Stamatina Kollontzi ◽  
Michael J Goedken ◽  
...  
Keyword(s):  
Late Stage ◽  
Food Packaging ◽  
Fetal Liver ◽  
Intratracheal Instillation ◽  
Fetal Tissue ◽  
Sprague Dawley ◽  
Plastic Pollution ◽  
Placental Perfusion ◽  
Fetal Tissues ◽  
The Impact

Abstract Background: Plastic is everywhere. It is used in food packaging, storage containers, electronics, furniture, clothing, and common single-use disposable items. Microplastic and nanoplastic particulates are formed from bulk fragmentation and disintegration of plastic pollution. Plastic particulates have recently been detected in indoor air and remote atmospheric fallout. Due to their small size, microplastic and nanoplastic particulate in the atmosphere can be inhaled and may pose a risk for human health, specifically in susceptible populations. When inhaled, nanosized particles have been shown to translocate across pulmonary cell barriers to secondary organs, including the placenta. However, the potential for maternal-to-fetal translocation of nanosized-plastic particles and the impact of nanoplastic deposition or accumulation on fetal health remain unknown. In this study we investigated whether nanopolystyrene particles can cross the placental barrier and deposit in fetal tissues after maternal pulmonary exposure.Results: Pregnant Sprague Dawley rats were exposed to 20 nm rhodamine-labeled nanopolystyrene beads (2.64 x 1014 particles) via intratracheal instillation on gestational day (GD) 19. Twenty-four hours later on GD 20, maternal and fetal tissues were evaluated using fluorescent optical imaging. Fetal tissues were fixed for particle visualization with hyperspectral microscopy. Using isolated placental perfusion, a known concentration of nanopolystyrene was injected into the uterine artery. Maternal and fetal effluents were collected for 180 minutes and assessed for polystyrene particle concentration. Twenty-four hours after maternal exposure, fetal and placental weights were significantly lower (7% and 8%, respectively) compared with controls. Nanopolystyrene particles were detected in the maternal lung, heart, and spleen. Polystyrene nanoparticles were also observed in the placenta, fetal liver, lungs, heart, kidney, and brain suggesting maternal lung-to-fetal tissue nanoparticle translocation in late stage pregnancy.Conclusion: These studies confirm that maternal pulmonary exposure to nanopolystyrene results in the translocation of plastic particles to placental and fetal tissues and renders the fetoplacental unit vulnerable to adverse effects. These data are vital to the understanding of plastic particulate toxicology and the developmental origins of health and disease.

Abstract 14297: Potential Role of the Tumor Suppressor WWOX in Mediating Skeletal Muscle-Lung Vasculature Crosstalk in PH-HFpEF

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Gunner Halliday ◽  
Yang Bai ◽  
Marta T Gomes ◽  
Dmitry Goncharov ◽  
Elena Goncharova ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Tumor Suppressor ◽  
Potential Role ◽  
Pulmonary Vascular Remodeling ◽  
Expression Levels ◽  
Promote Cell Proliferation ◽  
Pulmonary Arterial ◽  
Arterial Smooth Muscle Cells ◽  
Group 2

Introduction: Pulmonary hypertension due to left heart disease (PH-LHD; Group 2), particularly in the context of heart failure with preserved ejection fraction (HFpEF), is the most common cause of PH worldwide. At present, no specific effective therapy has been identified mainly due to the fact that major pathways involved in the regulation of PH-HFpEF are still not well understood. Results: We have recently reported on a role of skeletal muscle sirtuin-3 (SIRT3) in modulating PH-HFpEF. Using skeletal muscle-specific SIRT3 knockout mice ( Sirt3 skm-/- ), we showed that absence of SIRT3 in skeletal muscle drastically reduced the pulmonary vascular tree accompanied by vascular proliferative remodeling. Interestingly, we found that expression levels of the tumor suppressor WW domain-containing oxidoreductase (WWOX) were decreased in pulmonary arterial smooth muscle cells (PASMCs) obtained from Sirt3 skm-/- mice, while no changes in SIRT3 activation levels were detected. Reduced WWOX expression levels were also found in PASMCs isolated from SU5416/Obese ZSF1 (Ob-Su) rat model of PH-HFpEF, in which the levels of SIRT3 activation were found to be decreased in skeletal muscle, but not in the lungs and PASMCs. No changes of WWOX levels were observed in skeletal muscle of Ob-Su rats or in pulmonary artery endothelial cells (PAECs) treated with plasma obtained from Ob-Su rats. Conclusions: Since reduction of WWOX in PASMCs has been shown to promote cell proliferation, HIF1α stabilization and pulmonary arterial hypertension (PAH; Group 1), our data suggest a potential role of WWOX in mediating skeletal muscle SIRT3 deficiency-associated remote pulmonary vascular remodeling in PH-HFpEF.

Allele-specific in situ hybridization (ASISH) analysis: a novel technique which resolves differential allelic usage of H19 within the same cell lineage during human placental development

Development ◽  
1996 ◽  
Vol 122 (3) ◽  
pp. 839-847 ◽  
Author(s):  
G.I. Adam ◽  
H. Cui ◽  
S.J. Miller ◽  
F. Flam ◽  
R. Ohlsson
Keyword(s):  
In Situ Hybridization ◽  
First Trimester ◽  
Paternal Allele ◽  
Monoallelic Expression ◽  
Hybridization Technique ◽  
Placental Development ◽  
Foetal Development ◽  
Biallelic Expression ◽  
Normal Human

Precursory studies of H19 transcription during human foetal development have demonstrated maternally derived monoallelic expression. Analyses in extra-embryonic tissues, however, have been more equivocal, with discernible levels of expression of the paternal allele of H19 documented in the first trimester placenta. By refining the in situ hybridization technique we have developed an assay to enable the functional imprinting status of H19 to be determined at the cellular level. This assay involves the use of oligonucleotide DNA probes that are able to discriminate between allelic RNA transcripts containing sequence polymorphisms. Biallelic expression of H19 is confined to a subpopulation of cells of the trophoblast lineage, the extravillous cytotrophoblast, while the mesenchymal stroma cells maintain the imprinted pattern of monoallelic expression of H19 throughout placental development. This data demonstrates that the low level of paternal H19 expression previously detected in normal human placenta is not due to a random loss of functional imprinting, but appears to result from a developmentally regulated cell type-specific activation of the paternal allele. In addition, biallelic expression of H19 does not seem to affect the functional imprinting of the insulin-like growth factor II gene, which is monoallelically expressed at relatively high levels in the extra-villous cytotrophoblasts. These results imply that the allelic usage of these two genes in normal human placental development may not be directly analogous to the situation previously documented in the mouse embryo.

Abstract 20140: Minibrain Relate Kinase / Dyrk1B Links Skeletal Muscle Glycolytic Metabolism with Insulin Resistance and Causes Metabolic Syndrome

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Mohsen Fathzadeh ◽  
Ali Reza Keramati ◽  
Gwang Go ◽  
Rajvir Singh ◽  
Kazem Sarajzadeh ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Skeletal Muscle ◽  
Metabolic Syndrome ◽  
Protein Expression ◽  
Ppar Gamma ◽  
Glycolytic Metabolism ◽  
Expression Levels ◽  
Fiber Composition ◽  
Mutation Carriers ◽  
Fast Twitch

We have identified a novel nonconservative mutation in Minibrain related serine/threonine kinase (Mirk/ Dyrk1B) in outlier kindreds with metabolic syndrome. The mutation substitutes cysteine for arginine (R102C) and segregates with most traits of metabolic syndrome, including central obesity, diabetes and hypertension. Oral glucose tolerance test (OGTT) in young nondiabetic mutation carriers revealed insulin resistance compared to noncarrier family members. Since skeletal muscle (SM) is the largest organ for glucose uptake and metabolism, we obtained Vastus Lateralis biopsies of mutation carriers and their unaffected relatives and examined them for gene/protein expression by deep RNA sequencing (RNA-Seq) and Western blot analysis and for fiber composition by immunostaining. The fiber composition data demonstrated fewer slow-twitch fibers (35% vs. 75%) and more fast -twitch fibers (65% vs. 25%) in SM of mutation carriers vs. controls. Interestingly, there were increased protein expression levels of fast-twitch fiber type proteins (MYH11, MYLPF), pyruvate dehydrogenase kinase, pyruvate kinase, and neuronal nitric oxide synthase in SM of mutation carriers vs. noncarriers. Consistent with these findings, the protein expression levels of the master regulator of cellular energy metabolism mitochondrial biogenesis, PPAR-gamma coactivator (PGC-1a), were reduced and the nuclear expression levels of FOXO1 and NFAT were increased. Similar findings were observed when wildtype and mutant (R102C) Dyrk1B were overexpressed in C2C12 cells. The overexpression of the kinase deficient Dyrk1B (Y271/273F) similarly resulted in reduced expression of PGC-1a and increased expression of nuclear FOXO1, suggesting kinase independent effects. Taken together, these findings suggest that enhanced kinase-independent activities of Dyrk1B, either through increased expression or by its gain of function mutation R102C induce insulin resistance by promoting glycolytic metabolism and reducing oxidative phosphorylation. In conclusion, Dyrk1B is a potential target for development of novel drugs that aim to enhance skeletal muscle insulin sensitivity.

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