Effects of Intrauterine Growth Restriction on Ribosomal Subunit mRNA and Protein Expression in the Frontal Cortex of Near-Term Fetal Baboons
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ABSTRACT: Decreased fetal nutrient delivery is a major cause of developmental neuropathology. Although intrauterine growth restriction spares fetal brain weight, we hypothesized that frontal cortices of fetuses of mothers nutrient restricted during pregnancy, would have decreased ribosomal protein expression. This could potentially result in compromised function since these cellular subunits play a central role in protein synthesis and cellular energetics. Fetal baboons from mothers fed as ad lib controls (CTR) or globally nutrient restricted (MNR) by 30% from 30 - 165 days of gestation (term ~ 184 days in length) were studied. At necropsy, the average body weight of CTR mothers had increased by 11.3% while that of MNR mothers had decreased by 5.5% from before pregnancy. Body weights of MNR fetuses were 17% smaller than CTR fetal weights, but fetal brains were not different. As measured by gene array, 24 of 75 ribosomal protein mRNAs detected were decreased. Protein expression of 7 of 8 ribosomal proteins, assessed by semi-quantitative immunohistochemistry, was significantly (p< 0.05) or marginally (p > 0.05 < 0.1) decreased. The brains of growth-restricted fetuses are often assumed to be normal because of brain growth sparing. However, the present findings regarding ribosomal protein expression, strongly suggest that nutrient restriction in pregnancy, regardless of cause, inhibits protein synthesis in the fetal brain. In addition, these effects may be exacerbated if continued postnatally with possible effects on important protein dependent processes such as long-term memory storage.
Project description:We have developed a baboon nonhuman primate (NHP) model of maternal nutrient reduction during fetal development (30% global maternal nutrient reduction, MNR) to evaluate the impact of reduced nutrient availability on primate fetal development. We reported (Antonow-Schlorke et al. PNAS, 2011) that MNR induced major cerebral developmental disturbances at mid gestation (0.5G); however, the impact of MNR at late gestation (0.9G) and the mechanisms mediating these effects have not been determined. We hypothesized that MNR alters developmental trajectories of the fetal prefrontal cortex in the late gestation via miRNA regulation of key transcriptional and translational signaling pathways. Pregnant baboons were fed either ad libitum (control; CON; females n=3; males n=3) or a globally reduced diet (70% of controls; females n=3; males n=3) from 0.16G through 0.9G that produces IUGR (14% reduction in fetal weight). Fetuses were removed by Cesarean section at 0.9G, and prefrontal cortex (PFC) sections collected for analysis. Transcriptome (gene arrays) and small transcriptome (small RNA-Seq) analyses of fetal PFC were performed and gene and miRNA profiles were compared between MNR and CON. We present for the first time transcriptome (GSE42756) and small RNA transcriptome expression profiles of the fetal baboon PFC at 0.9G. Pathway analysis showed that MNR had sex-specific effects on key cellular signaling pathways. We conclude that moderate maternal global nutrient reduction during pregnancy can alter signaling pathways related to nutrient sensing and cell proliferation in the late gestation PFC. In addition, inverse expression of miRNAs known to target genes in these pathways suggests that miRNA mechanisms play a role in these changes.
Project description:We used microarrays to determine the transcriptional profiles of placental tissue obtained from women who smoked during pregnancy and from women who did not smoke during pregnancy. Fetal growth restriction is a frequent complication in mothers who smoke cigarettes during pregnancy. To evaluate novel pathways that regulate fetal growth affected by mothers who smoke, we isolated placental mRNA from smoking mothers with severe fetal growth restriction and compared them by microarray analysis to non-smoking mothers with appropriately grown fetuses. Bioinformatics analysis revealed distinct transcriptional patterns in the placentas of smoking mothers when compared to placentas from control non-smoking women. Analyses of the top upregulated and downregulated genes revealed several gene products such as secreted frizzled related protein 1 that was markedly upregulated in the placentas from women who smoked cigarettes during pregnancy.
Project description:We used microarrays to determine the transcriptional profiles of placental tissue obtained from women who smoked during pregnancy and from women who did not smoke during pregnancy. Fetal growth restriction is a frequent complication in mothers who smoke cigarettes during pregnancy. To evaluate novel pathways that regulate fetal growth affected by mothers who smoke, we isolated placental mRNA from smoking mothers with severe fetal growth restriction and compared them by microarray analysis to non-smoking mothers with appropriately grown fetuses. Bioinformatics analysis revealed distinct transcriptional patterns in the placentas of smoking mothers when compared to placentas from control non-smoking women. Analyses of the top upregulated and downregulated genes revealed several gene products such as secreted frizzled related protein 1 that was markedly upregulated in the placentas from women who smoked cigarettes during pregnancy. Total RNA was isolated from placental specimens obtained at time of delivery. RNA was hybridized to Affymetrix arrays, and analyzed.
Project description:Poor maternal nutrition during pregnancy causes intrauterine growth retardation, which, in turn, is associated with increased risk of cardiovascular and metabolic diseases in later life Fetal hearts were collected from baboon fetuses born to regularly fed and undernurished mothers. Total RNA was isolated, and fetal cardiac miRNA were profiled
Project description:Fetal growth restriction (FGR) affects between 5-10% of all live births. Placental insufficiency is a leading cause of FGR, resulting in reduced nutrient and oxygen delivery to the fetus. Currently, there is no effective in utero treatment options for FGR, or placental insufficiency. We have developed a gene therapy to deliver human insulin-like 1 growth factor (hIGF1) to the placenta via a non-viral nanoparticle delivery mechanism as potential treatment of FGR. Using a guinea pig maternal nutrient restriction (MNR) model of FGR, we aimed to understand the transcriptional changes within the placenta associated with placental insufficiency that occur at the beginning stages of FGR (mid-pregnancy), and the immediate impact of hIGF1 nanoparticle treatment on the placental transcriptome. Using RNAsequencing, we analyzed protein coding genes of three experimental groups: Control dams and MNR receiving a sham treatment, and MNR dams receiving hIGF1 nanoparticle treatment. Pathway enrichment analysis comparing MNR placentas to Control revealed upregulation of pathways associated with degradation and repair of genetic information and downregulation of pathways associated with transmembrane transport. Similarly, differentially expressed genes that were decreased in MNR + hIGF1 placentas compared to Control demonstrated downregulation in pathways relating to transporter activities, but upregulation in pathways associated with positive regulation of phosphorylation and kinase activity. When compared to MNR placentas, MNR + hIGF1 placentas demonstrated changes to genes associated with transmembrane transporter activity including ion, vitamin and solute carrier (SLC-mediated) transport. Overall, this study identifies the key signaling and metabolic changes occurring in the placenta that contribute to placental insufficiency, and increases our understanding of the pathways that increasing placental IGF1 expression acts on and corrects.
Project description:Maternal obesity programs the offspring to cardiovascular disease, insulin resistance, and obesity. We sequenced and profiled the cardiac miRNAs that were dysregulated in the hearts of baboon fetuses born to a high fat / high fructose diet fed mothers compared to a regular diet fed mothers. Fetal hearts were collected from baboon fetuses born to obese and lean mothers, total RNA was isolated, and fetal cardiac miRNA were sequenced and profiled
Project description:The present study aimed to examine the effect of high-fat diet prior to pregnancy on the liver of mouse offspring. Female C57BL/6J mice were fed a normal chow (15.2% fat by energy) (CTR and CTR-PP groups) or a high-fat chow (31.2% fat by energy) (HFD and HFD-PP groups) for 3−4 weeks and then mated with male C57BL/6J mice fed normal chow. Some mothers continued on the same diet until pups reached 21 days of age (CTR and HFD), and others were fed the different chows from gestational day 0 (CTR-PP and HFD-PP) to determine the effects of a high-fat diet during the pre-pregnancy period in HFD-PP/CTR and HFD/CTR-PP comparisons.
Project description:The present study aimed to examine the effect of high-fat diet prior to pregnancy on the liver of mouse offspring. Female C57BL/6J mice were fed a normal chow (15.2% fat by energy) (CTR and CTR-PP groups) or a high-fat chow (31.2% fat by energy) (HFD and HFD-PP groups) for 3−4 weeks and then mated with male C57BL/6J mice fed normal chow. Some mothers continued on the same diet until pups reached 21 days of age (CTR and HFD), and others were fed the different chows from gestational day 0 (CTR-PP and HFD-PP) to determine the effects of a high-fat diet during the pre-pregnancy period in HFD-PP/CTR and HFD/CTR-PP comparisons. RNA sample was taken from liver of 3-week-old mouse prenatally received high-fat diet prior to pregnancy, during pregnancy and lactation, or through prior to and during pregnancy and lactation, while control RNA was taken from control counterpart prenatally received normal diet alone. Comparisons among groups were made by one-color method with normalized data from Cy3 channels for data analysis.
Project description:We conducted proteome analysis of basilar (cerebral) arteries from three control baboon fetuses and four fetuses that were exposed to alcohol in utero. Three alcohol-exposure episodes took place during second trimester-equivalent of human pregnancy, while fetal arteries were harvested during cesarean sections performed near-term. Supernatants from whole artery lysates were processed for TMT-labeling, fractionated, and subjected to LC/MS analysis.
Project description:Placental development is modified in response to maternal nutrient restriction (NR) resulting in a spectrum of fetal growth rates. Pregnant sheep carrying singleton fetuses and fed either 100% (n=8) or 50% (NR; n=28) of their National Research Council (NRC) recommended intake from Days 35 to 135 of pregnancy were used to elucidate placentome transcriptome alterations at both Day 70 and 135. NR fetuses were further designated into upper (NR NonSGA; n=7) and lower quartiles (NR SGA; n=7) based on Day 135 fetal weight. At Day 70 of pregnancy, there were 22 genes dysregulated between NR SGA and 100% NRC placentomes, 27 genes between NR NonSGA and 100% NRC placentomes, and 22 genes between NR SGA and NR NonSGA placentomes. These genes mediated molecular functions such as MHC class II protein binding, signaling receptor binding, and cytokine activity. Gene Set Enrichment Analysis (GSEA) revealed significant overrepresentation of genes for natural killer cell-mediated cytotoxicity in NR SGA compared to 100% NRC placentomes and alterations in nutrient utilization pathways between NR SGA and NR NonSGA placentomes at Day 70. Results identify novel factors associated with impaired function in SGA placentomes and potential for placentomes from NR NonSGA pregnancies to adapt to nutritional hardship.