Effects of Triclosan exposition on fetal hypothalamic transcriptomics
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ABSTRACT: Triclosan (TCS), an antibacterial compound commonly added to personal care products, could be an endocrine disruptor at low doses. Although TCS has been shown to alter fetal physiology, its effects in the developing fetal brain are unknown. The objective of this study was to use transcriptomics and systems analysis to determine significantly altered biological processes in the late gestation ovine fetal hypothalamus after direct or indirect exposure to low doses of TCS. We found that short-term infusion of TCS induces vigorous changes in the fetal hypothalamic transcriptomics, which are mainly related to food intake pathways and metabolism. For direct TCS exposure, chronically catheterized late gestation fetal sheep were infused with vehicle (n=4) or TCS (250 μg/day; n=4) iv. For indirect TCS exposure, TCS (100 μg/kg/day; n=3) or vehicle (n=3) was infused into the maternal circulation. Fetal hypothalami were collected after 2 days of infusion, and gene expression was measured using Agilent 15k ovine microarrays.
Project description:The late-gestation fetal lung has relatively high levels of expression of the mineralocorticoid receptor (MR) as well as the glucocorticoid receptor (GR), suggesting that endogenous corticosteroids may act in the lung through binding at MR as well as GR. This study was designed to determine the effects of physiologically relevant increases in steroids on MR and GR in the late-gestation lung. The GR agonist, betamethasone, the MR agonist, aldosterone, or both agonists were infused intravenously for 48 hours in ovine fetuses of approximately 130 days gestation. Effects on airway pressures during stepwise inflation of the in situ lung, expression of ENaC and Na,K ATPase, and elastin and collagen content were determined at the end of the infusions. We found that aldosterone significantly reduced the initial airway pressures measured in situ during inflation. This effect did not occur with betamethasone alone or in combination with aldosterone. Conversely, betamethasone, but not aldosterone, significantly increased expression of the epithelial sodium channel (ENaC) subunit mRNAs, and collagen and elastin content in the lungs. Aldosterone altered novel gene pathways in the fetal lung, suggesting effects on lung compliance via genes which influence immune pathways and lung stiffness. The results are consistent with corticosteroid-induced fluid reabsorption at birth through GR rather than MR, but suggest that MR contributes effects facilitating lung inflation with the first breaths via nonclassical mechanisms. 4 sets of twin sheep fetuses at approximately 130d gestation (term is 147d) were used. One twin was infused with 0.2 mg aldosterone for 48 h, the other received vehicle.
Project description:We have previously shown in sheep that 10 days of modest chronic increase in maternal cortisol result in fetal heart enlargement and Purkinje cell apoptosis. In subsequent studies in which we extended the duration of cortisol infusion (1mg/kg/d) to term, we found a dramatic incidence of stillbirth in the pregnancies with chronically increased cortisol and associated maternal hyperglycemia. To investigate the effects on the heart, transcriptomic analyses were performed on the septa using ovine microarrays and Webgestalt and Cytoscape programs for pathway inference. Analyses of the effects of 10 days of maternal cortisol infusion (130d-cortisol vs 130d control), ~25 days (term at ~140d-cortisol vs 140d control), normal maturation (140d-control vs 130d control) were performed. In all analyses gene ontology (GO) terms related to immune function and cytokine actions were significantly over-represented. After 10 days of cortisol, growth factor and muscle cell apoptosis pathways were significantly over-represented, consistent with our previous findings. We found significantly differentially regulated genes in the term fetuses (ie after ~25 days of cortisol) in pathways consistent with altered metabolism in the heart, particularly in mitochondria, associated with responses to hypoxia and to nutrient. Analysis of mitochondrial number by quantitative real-time PCR confirmed a significant decrease. These pathways were different from those modeled following the normal increase in cortisol in late gestation which contributes to normal maturation of the heart, and thus may be indicative of the fetal heart pathophysiologies seen in pregnancies complicated by diabetes, CushingM-bM-^@M-^Ys disease and chronic stress. 2 cohorts of singleton sheep fetuses at 129-131d gestation or 139-144d gestation (approximately term) were used. The first cohort received maternal cortisol infusion of 1mg/kg/day or vehicle for 10 days until approximately day 130 of gestation (n=6/group), the second cohort received the same dose of cortisol for approximately 25 days until near term (n=7, cortisol; n=7ewes, n=8 fetuses due to one set of twins, control)
Project description:Triclosan (TCS), an antibacterial compound commonly added to personal care products, could be an endocrine disruptor at low doses. Although TCS has been shown to alter fetal physiology, its effects in the developing fetal brain are unknown. The objective of this study was to use transcriptomics and systems analysis to determine significantly altered biological processes in the late gestation ovine fetal hypothalamus after direct or indirect exposure to low doses of TCS. We found that short-term infusion of TCS induces vigorous changes in the fetal hypothalamic transcriptomics, which are mainly related to food intake pathways and metabolism.
Project description:The period of development from the last two weeks of gestation through the first two weeks of life spans a period of great functional and metabolic challenge to the fetal and neonatal lamb heart. Important changes in gene expression occur to meet these challenges. On this study, septa from sheep hearts at 130 days gestation (n=6), term (n=8, gestational lenght is around 145 days) and 14-days-old lambs (n=8) were used to model the changes in gene expression patterns during the perinatal period using Agilent 15k ovine microarrays. Weighted gene co-expression network analysis (WGCNA) determined five major patterns of co-expressed and functionally related genes during this critical period of cardiac transition. Septum samples from the heart were collected from non-treated fetuses at 130 days of gestational age (GA130d, n=6) and term (n=8); and from naturally born 14-days-old lambs (Lamb, n=8). None of the ewes suffered gestational diseases or showed signs of impending labor.
Project description:In the fetal sheep during late gestation sulfoconjugated estrogens in plasma reach a concentration 40-100 times greater than unconjugated estrogens. The objective of the present study was to determine the genomics of estradiol-3-sulfate (E2S) action in the fetal brain. The hypothesis was that E2S stimulates genes involved in the neuroendocrine pathways in the hypothalamus that direct or facilitate fetal development at the end of gestation. Four sets of chronically-catheterized ovine twin fetuses were studied (gestational age: 120-127 days gestation) with one infused with E2S intracerebroventricularly (1 mg/day) and the other remained untreated (control). After euthanasia, mRNA samples were extracted from the 8 hypothalami, corresponding to the four treatment and four control fetuses. Microarray analysis was performed following the Agilent protocol for 1-color 8x15 microarrays, designed for Ovis aries. A total of 4 sets of chronically-catheterized ovine twin fetuses were studied with one infused with estradiol-3-sulfate intracerebroventricularly (1 mg/day) for 7-12 days, using an osmotic mini-pump implanted in the fetus, and the other served as an untreated control. The gestational age at the time of surgery was 120-127 days of gestation. Twin fetuses were randomly assigned to the two groups at the time of surgery. After 7-12 days of infusion, twin fetuses of known gestational age (130 to 134 days) were euthanized and mRNA samples were extracted from the 8 hypothalami, corresponding to the four treatment and four control fetuses.
Project description:Liver plays a profound role in the acute phase response (APR) observed in the early phase of acute bovine mastitis caused by Escherichia coli (E. coli). To gain an insight into the genes and pathways involved in hepatic APR of dairy cows we performed a global gene expression analysis of liver tissue sampled at different time points before and after intra-mammary (IM) exposure to E. coli lipopolysaccharide (LPS) treatment. Experiment Overall Design: Eight healthy, high yielding Holstein-Friesian dairy cows in their first lactation (9 to 12 weeks after calving) were chosen for this study. At time 0 the right front quarter was infused with 200 μg E. coli LPS dissolved in 10 ml 0.9% NaCl solution, the left front quarter serving as control was infused with 10 ml 0.9% NaCl solution. Liver biopsies were taken at â22, 3, 6, 9, 12 and 48 hours relative to LPS infusion in 4 cows, and also at â22, 9 and 48 hours in the remaining 4 cows. RNA from liver biopsies was isolated and biotin labeled cRNA was loaded onto the Affymetric GeneChip Bovine Genome Array. A control study using cows infused with 0.9% NaCl showed that there was no effect of taking the biopsy, neither in the clinical measurement nor in the expression of a selected subset of genes. Therefore, only samples taken from the LPS treated cows were measured for the gene expression using microarrays.
Project description:Comparing the transcriptional responses of Bacillus subtilis strains WN624 and WN1106 at 5 kPa and 101 kPa. WN1106 is a 5 kPa-evolved strain with increased fitness compared to ancestor-WN624 strain at 5 kPa. This experiment probed the difference in response when the strains are grown at 5 kPa. Two-condition experiment, 5 kPa vs. 101 kPa, for both strains. And two component condition of WN1106 compared to WN624 at either 5 kPa or 101 kPa. 4 pressure comparisons.
Project description:Estradiol plays a critical role stimulating the fetal hypothalamus-pituitary-adrenal axis at the end of gestation. Estradiol action is mediated through nuclear and membrane receptors that can be modulated by ICI 182,780, a pure anti-estrogen compound. The objective of this study was to evaluate the transcriptomics of estradiol and ICI 182,780, testing the hypothesis that ICI 182,780 blocks the action of estradiol in the fetal hypothalamus. However, we found that a short term (48 hrs) infusion with ICI 182,780 induces a similar transcriptomic response than estradiol infusion in the late gestation ovine fetal hypothalamus, being more evident with higher doses of ICI 182,780. These results suggest that ICI 182,780 is primarily an agonist of estradiol in the developing brain.
Project description:Aiming at the development of a micropollutant biosensor in the frame of the Micro-Ecological Life Support System Alternative (MELiSSA), a pilot study was initiated to identify triclosan (TCS)-responsive biomarker genes in the MELiSSA carbon-mineralizing microorganism, Rhodospirillum rubrum S1H. TCS is a biocide, commonly found in human excrements and is considered an emerging pollutant in wastewater and the environment. Chronic exposure to MELiSSA-relevant concentrations (≥25 µg L-1) TCS caused a significant extension of the lag phase without affecting the growth rate. Analytical determination gave no indication of TCS biodegradation during the growth experiment and flow cytometric viability analyses revealed that TCS is only slightly toxic to R. rubrum. Through microarray analyses, the genetic mechanisms supporting the reversibility of TCS-induced inhibition were scrutinized. Hence, an extremely TCS-responsive cluster of four small adjacent genes was revealed, with up to 34-fold induction at 25 µg L-1. These four genes, for which the name micropollutant-upregulated factor (muf) was proposed; appear to be unique to R. rubrum and are shown for the first time to be involved in the response to stress. Moreover, numerous other systems that are associated with the proton-motive force were shown to be responsive to TCS, but never as highly upregulated as the muf genes. Hence, R. rubrum induced the phage shock protein operon (pspABC), numerous major facilitator efflux systems, cell envelope consolidation mechanisms, oxidative stress response, beta-oxidation, and carbonic anhydrase; while downregulating bacterial conjugation- and carboxysome synthesis genes. The muf genes and three efflux-related genes showed most potential as low-dose biomarkers. The two microarray experiments (10 and 25 µg l-1 Triclosan) were all performed in biological triplicate and containing three (in-slide) technical repeats. For all conditions, the Triclosan exposed sample (Cy5) was compared with the non-exposed solvent control (Cy3) to identify those genes that were differentially expressed upon Triclosan exposure.
Project description:miR-93/106b and their host gene minichromosome maintenance complex component 7 (MCM7) reside at chr7q22, a region frequently rearranged in leiomyomas. We explored the expression of miR-93/106b in leiomyoma and paired myometrium (N=62) from untreated and patients exposed to hormonal therapies (GnRHa, Depo-Provera and oral contraceptives) from African Americans and Caucasians, and their regulatory functions in isolated paired (N=15) leiomyoma and myometrial smooth muscle cells (LSMC and MSMC) and leiomyosarcoma cell line (SKLM-S1). At tissue level leiomyomas expressed significantly lower levels of miR-93 and elevated MCM7 as compared to myometrium with limited racial influence or hormonal exposure on their expression. Assessing the regulatory function of miR-93/106b through doxycycline-inducible lentiviral transduction in microarray analysis, tissue factor (F3) and IL-8 were identified as their possible targets. At tissue level leiomyomas expressed a significantly lower level of F3 and an elevated IL-8 which exhibited an inverse relationship with miR-93, but with limited racial or hormonal influences. Gain-of-function of miR-93/106b in LSMC, MSMC and SKLM-S1 dose-dependently repressed F3 and IL-8 through direct interactions with their respective 3M-bM-^@M-^YUTRs and indirectly through F3 repression inhibited IL8, CTGF and PAI-1 expression, confirmed by using siRNA silencing or factor Vlla (FVIIa) activation of F3, as well as reducing the rate of proliferation, while increasing caspase 3/7 activity. We concluded that differential expression of miR-93/106b and their direct and/or indirect regulatory functions on F3, IL-8, CTGF and PAI-1 expression, with key roles in inflammation and tissue turnover may be of significance in the outcome of leiomyoma growth and associated symptoms. Total RNA isolated from TF324 cells transfected with DOX-inducible lentiviral construct carrying miR-106b~25 cluster with and without Dox treatments for 6 days was subjected to gene expression profiling using Sentirx Beadchip Array HumanHT-12_v4.