ABSTRACT: Repeated gestational exposure of mice to chlorpyrifos oxon is associated with paraoxonase 1 (PON1)-modulated effects in maternal and fetal tissues
Project description:Chlorpyrifos oxon (CPO), the toxic metabolite of the organophosphorus (OP) insecticide chlorpyrifos, causes developmental neurotoxicity in humans and rodents. CPO is hydrolyzed by paraoxonase-1 (PON1), with protection determined by PON1 levels and the human Q192R polymorphism. To examine how the Q192R polymorphism influences fetal toxicity associated with gestational CPO exposure, we measured biomarker inhibition and fetal-brain gene expression in wild-type (PON1+/+), PON1-knockout (PON1-/-), and tgHuPON1R192 and tgHuPON1Q192 transgenic mice. Pregnant mice exposed dermally to 0, 0.50, 0.75 or 0.85 mg/kg/d CPO from gestational days (GD) 6 through 17 were sacrificed on GD18. Biomarkers of CPO exposure inhibited in maternal tissues included brain acetylcholinesterase (AChE), RBC acylpeptide hydrolase (APH), plasma butyrylcholinesterase (BChE) and carboxylesterase (CES). Fetal plasma BChE was inhibited in PON1-/- and tgHuPON1Q192, but not PON1+/+ or tgHuPON1R192 mice. Fetal brain AChE and plasma CES were inhibited in PON1-/- mice, but not in other genotypes.
Project description:Chlorpyrifos oxon (CPO), the toxic metabolite of the organophosphorus (OP) insecticide chlorpyrifos, causes developmental neurotoxicity in humans and rodents. CPO is hydrolyzed by paraoxonase-1 (PON1), with protection determined by PON1 levels and the human Q192R polymorphism. To examine how the Q192R polymorphism influences fetal toxicity associated with gestational CPO exposure, we measured biomarker inhibition and fetal-brain gene expression in wild-type (PON1+/+), PON1-knockout (PON1-/-), and tgHuPON1R192 and tgHuPON1Q192 transgenic mice. Pregnant mice exposed dermally to 0, 0.50, 0.75 or 0.85 mg/kg/d CPO from gestational days (GD) 6 through 17 were sacrificed on GD18. Biomarkers of CPO exposure inhibited in maternal tissues included brain acetylcholinesterase (AChE), RBC acylpeptide hydrolase (APH), plasma butyrylcholinesterase (BChE) and carboxylesterase (CES). Fetal plasma BChE was inhibited in PON1-/- and tgHuPON1Q192, but not PON1+/+ or tgHuPON1R192 mice. Fetal brain AChE and plasma CES were inhibited in PON1-/- mice, but not in other genotypes. Pregnant mice (wild type (WT), PON1-knockout (KO), tgHuPON1R192 (R-tg) and tgHuPON1Q192 (Q-tg)) were exposed to various amounts of CPO (0, 0.5, 0.75 and 0.85 mg/kg/d) for 12 days (gestational days 6-17). On gestational day 18, dams were sacrificed and fetal brains were collected. A total of 264 fetal brains from 80 dams were processed to extract total RNA using TRIZOL and the QIAamp Tissue kit from QIAGEN. Microarray analysis was performed using the fetuses of 5 dams per experimental group (total RNA was pooled from individual fetal brains from each dam). The dams used for fetal-brain microarray analysis were selected using a random-number generator, after first eliminating dams with brain AChE activities > 1.5 SD compared to the mean for their treatment group. RNA samples isolated from individual fetal brains from each dam were combined, then labeled and hybridized to Affymetrix Mouse Gene 1.0 ST microarrays.
Project description:Chlorpyrifos (CPF) is an organophosphorus (OP) insecticide that is still widely used despite statutory restrictions on home use. CPF is converted to chlorpyrifos oxon (CPO) by oxidative desulfuration in liver. Paraoxonase (PON1) polymorphisms affects the catalytic efficiency of the hydrolysis of OPs, including CPO. We used both wt (PON1+/+) and PON1 knockout (PON1-/-) mice and PON1-/- mice carrying transgenes encoding the human alloforms tgHuPON1Q192 and tgHuPON1R192 to gain insight into the mechanisms of neurotoxicity of CPO throughout postnatal development, and to ascertain the importance of the PON1Q192R polymorphism for protecting against developmental toxicity of CPO. Whole-genome microarrays were used to measure gene expression changes associated with chronic CPO exposure of developing (PND 4-21) PON1-/-, tgHuPON1Q192R transgenic and PON1+/+ mice. Expression profiles are derived from cerebella from wild-type C57/Bl6 and PON1-/- on a C57/Bl6 background and two transgenic strains (tgHuPON1Q192, tgHuPON1R192) expressing either human PON1Q192 or human PON1R192 on the PON1-/- C57/Bl6 background. The mice were subjected to chronic postnatal exposure to CPO (CPO). Transgenic, PON1-KO and WT neonatal mice either treated with control (DMSO), 0.35 mg*kg-1*day-1 CPO or 0.5 mg*kg-1*day-1 CPO daily from PND 4 to PND 21. Chlorpyrifos (CPF) is converted to chlorpyrifos oxon (CPO) by oxidative desulfuration in liver. 55 arrays, 12 experimental groups (strain + treatment), due to QC issues the replicates are as follows; PON1-KO-0.35 (5), PON1-KO-.O5 (3), PON1-KO-DMSO (4), PON1-Q129-0.35 (5), PON1-Q129-0.5 (5), PON1-Q129-DMSO (4), PON1-R129-0.35 (5), PON1-R129-0.5 (5), PON1-R129-DMSO (4), WT-0.35 (6), WT-0.5 (3), WT-DMSO (6)
Project description:Chlorpyrifos (CPF) is an organophosphorus (OP) insecticide that is still widely used despite statutory restrictions on home use. CPF is converted to chlorpyrifos oxon (CPO) by oxidative desulfuration in liver. Paraoxonase (PON1) polymorphisms affects the catalytic efficiency of the hydrolysis of OPs, including CPO. We used both wt (PON1+/+) and PON1 knockout (PON1-/-) mice and PON1-/- mice carrying transgenes encoding the human alloforms tgHuPON1Q192 and tgHuPON1R192 to gain insight into the mechanisms of neurotoxicity of CPO throughout postnatal development, and to ascertain the importance of the PON1Q192R polymorphism for protecting against developmental toxicity of CPO. Whole-genome microarrays were used to measure gene expression changes associated with chronic CPO exposure of developing (PND 4-21) PON1-/-, tgHuPON1Q192R transgenic and PON1+/+ mice. Expression profiles are derived from cerebella from wild-type C57/Bl6 and PON1-/- on a C57/Bl6 background and two transgenic strains (tgHuPON1Q192, tgHuPON1R192) expressing either human PON1Q192 or human PON1R192 on the PON1-/- C57/Bl6 background. The mice were subjected to chronic postnatal exposure to CPO (CPO).
Project description:Human paraoxonase-1 (PON1) is an enzyme with lactonase, esterase and phosphotriesterase activity that has been associated with multiple phenotypes. We expressed hPON1 ubiquitously in Drosophila melanogaster using the Gal4 system Tub driver.
Project description:Compairsion of transcriptional profiles of heart and skeletal muscle tissue of fetal rhesus monkey exposed to maternal Bisphenol A or vehicle during early or late gestaion. Maternal exposure to the endocrine disrupting chemical, bisphenol A (BPA) affects the development of multiple organ systems in rodents and monkeys. However, effects of BPA exposure on cardiac and skeletal muscle development have not been assessed. Given that maternal BPA crosses placenta and reaches developing fetus, examining the physiological consequences of gestational exposure during development is of research significance. Therefore, we evaluate the effects of daily, oral BPA exposure of pregnant rhesus monkeys (Macaca mulatta) on the fetal heart and skeletal muscle transcriptome. Pregnant monkeys were administered daily oral doses (400 µg/kg body weight) of BPA during early (50 –100 ± 2 days post conception, dpc) or late (100 ± 2 dpc - term), gestation. At the end of treatment, fetal heart tissues; left ventricle (LV), right ventricle (RV), left atrium (LA), right atrium (RA) and skeletal muscle; biceps femoris (BFM), were collected. Transcriptome expression was assessed using genome-wide microarray in each of the tissues and compared paired-wise between the BPA and matched control fetuses. Our results show that maternal BPA exposure alters transcriptional profile of several coding and non-coding genes in fetal heart and skeletal muscle.
Project description:Infection-associated inflammatory stress during pregnancy is the most common cause of fetal growth restriction. Treatment strategies for protection of at-risk mothers are limited. Employing mouse models, we demonstrate that oral treatment during pregnancy with a microbial-derived immunomodulator (OM85), markedly reduces risk for fetal loss/growth restriction resulting from maternal challenge with bacterial LPS or influenza. Focusing on LPS exposure, we demonstrate that the key molecular indices of maternal inflammatory stress (RANTES, MIP-1a, CCL2, KC, G-CSF) in gestational tissues/serum, are abrogated by OM85 pretreatment. Systems-level analyses of RNASeq data revealed that OM85 pretreatment selectively tunes LPS-induced activation in maternal gestational tissues for attenuated expression of TNF-, IL1-, and IFNg- driven proinflammatory networks, without constraining Type1-IFN-associated networks central to first-line anti-microbial defense. This study suggests that broad-spectrum protection-of-pregnancy against infection-associated inflammatory stress, without compromising capacity for efficient pathogen eradication, represents an achievable therapeutic goal.
2016-10-24 | GSE85414 | GEO
Project description:Pseudogenization of Paraoxonase 1 (PON1) in Pinnipeds
Project description:In utero smoke exposure has adverse consequences for the child, including premature delivery, smaller birth weight and predisposition to disease later in life. The fetal liver has major detoxifying roles in addition to orchestrating the function of multiple organ systems. Maternal smoking increases the fetal toxin burden, and is expected to cause changes in the human fetal liver physiology likely contributing to disease and disease predisposition. In this project the transcriptional response in fetal liver tissue was analysed in relation to maternal smoke exposure, fetal sex and gestational age. Total RNA, protein and DNA were consecutively extracted from the same liver biopsy of electively terminated second trimester fetal livers. Proteomic analyses on the protein fraction were performed to allow for an integrated analysis of both the transcriptional and translational changes.
Project description:Prenatal environmental conditions may influence disease risk in later life. We previously found a gene-environment interaction between the paraoxonase 1 (PON1) Q192R genotype and prenatal pesticide exposure leading to a cardio-metabolic risk profile at school age. However, the molecular mechanisms involved have not yet been resolved. It has been hypothesized that epigenetics might be involved. The aim of the present study was to investigate whether DNA methylation patterns in blood cells were related to prenatal pesticide exposure level, PON1 Q192R genotype, and associated metabolic effects observed in the children. Whole blood DNA methylation patterns in 48 children (6-11 years of age), whose mothers were occupationally unexposed or exposed to pesticides early in pregnancy, were determined by Illumina 450K methylation arrays. A specific methylation profile was observed in prenatally pesticide exposed children carrying the PON1 192R allele. Differentially methylated genes were enriched in several neuroendocrine signaling pathways including dopamine-DARPP32 feedback (appetite, reward pathways), corticotrophin releasing hormone signalling, nNOS, neuregulin signalling, mTOR signalling and type II diabetes mellitus signalling suggesting a possible link with the metabolic effects observed in these children. Furthermore, we were able to identify possible candidate genes which mediate the effect between pesticide exposure, leptin levels, delta BMI Z-score, and body fat percentage. In conclusion, DNA methylation may be an underlying mechanism explaining cardio-metabolic health outcomes in children that are prenatally exposed to pesticides and carrier of the PON1 192R allele.