Data for O'Shaughnessy et al. 2023 - Bypassing the Brain Barriers: Upregulation of Serum miR-495 and miR-543-3p Reflects Thyroid-Mediated Developmental Neurotoxicity in the Rat. This dataset is associated with the following publication: O'Shaughnessy, K., A. Sasser, K. Bell, C. Riutta, J. Ford, R. Grindstaff, and M. Gilbert. Bypassing the Brain Barriers: Upregulation of Serum miR-495 and miR-543-3p Reflects Thyroid-Mediated Developmental Neurotoxicity in the Rat. TOXICOLOGICAL SCIENCES. Society of Toxicology, RESTON, VA, 198(1): 128-140, (2024).

This file contains summary data of thyroid hormones in serum and brain in rat dams and their pups following maternal exposure to a perflorinated substance, PFHxS and an antimicrobial, Triclosan. Gene expression in thyroid glands and liver and brain were investigated. Anatomical and bahavioral indices of developmental neurotoxicity were assessed. Result so fall of these inquiries are summarized in these datasets. This dataset is associated with the following publication: Gilbert, M.E., K. OShaughnessy, S. Thomas, C. Riutta, C. Wood, A. Smith, W. Oshiro, J. Ford, A. Hotchkiss, I. Hassan, and R.L. Ford. Thyroid Disruptors: Extrathyroidal Sites of Chemical Action and Neurodevelopmental Outcome-An Examination Using Triclosan and Perfluorohexane Sulfonate. TOXICOLOGICAL SCIENCES. Society of Toxicology, RESTON, VA, 183(6): 195-213, (2021).

Structural defects in the rat brain associated with maternal exposure to ammonium perchlorate accompanied reductions in circulating levels of thyroid hormone in the dam and the fetus. The magnitude of the effect was small relative to other thyroid hormone disruptors, but his was due to the lack of sufficient bioavailability of perchlorate to the nursing neonate. When pups were administered perchlorate directly for the first 6 days of life or if perchlorate was administered under conditions of maternal dietary iodine deficiency, very large brain malformations were induced. This dataset is associated with the following publication: Gilbert, M., K. O'Shaughnessy, K. Bell, and J. Ford. Structural Malformations in the Neonatal Rat Brain Accompany Developmental Exposure to Ammonium Perchlorate. Toxics. MDPI, Basel, SWITZERLAND, 11(12): 1027, (2023).

Raw data to accompanying manuscript "The Pollutant Perfluorohexane Sulfonate (PFHxS) Reduces Serum Thyroxine but Does Not Alter Thyroid Hormone Action in the Postnatal Rat Brain". This dataset is associated with the following publication: O'Shaughnessy, K., K. Bell, A. Sasser, M. Gilbert, C. Riutta, J. Ford, J. McCord, and C. Wood. The Pollutant Perfluorohexane Sulfonate (PFHxS) Reduces Serum Thyroxine but Does Not Alter Thyroid Hormone Action in the Postnatal Rat Brain. ENVIRONMENT INTERNATIONAL. Elsevier B.V., Amsterdam, NETHERLANDS, 190: 108838, (2024).

How to access data for "Decrane R, Stoker T, Murr A, Ford J, El-Masri H. Cross species extrapolation of the disruption of thyroid hormone synthesis by oxyfluorfen using in vitro data, physiologically based pharmacokinetic (PBPK), and thyroid hormone kinetics models. Curr Res Toxicol. 2023 Nov 23;5:100138. doi: 10.1016/j.crtox.2023.100138. PMID: 38074188; PMCID: PMC10697989.". This dataset is not publicly accessible because: N/A. It can be accessed through the following means: Data will be made available on request from Hisham El-Masri (el-masri.hisham@epa.gov). Format: N/A. This dataset is associated with the following publication: Decrane, R., T. Stoker, A. Murr, J. Ford, and H. El-Masri. Cross species extrapolation of the disruption of thyroid hormone synthesis by oxyfluorfen using in vitro data, physiologically based pharmacokinetic (PBPK), and thyroid hormone kinetics models. Current Research in Toxicology. Elsevier B.V., Amsterdam, NETHERLANDS, 5: 100138, (2023).

This dataset was generated to support parameterization of a larval amphibian thyroid axis computational model. Specifically, plasma iodine levels were determined not only to inform a concentration value for model parameter specification in the model, but also to support the notion that aquatic and terrestrial species should be considered substantially different with regard to circulating iodide levels. Other computational model physical parameters were informed by evaluating Xenopus laevis thyroid gland histological images for morphological features including thyroid follicular cell numbers and areas. This dataset is associated with the following publication: Haselman, J., J. Nichols, K. Mattingly, M. Hornung, and S. Degitz. A biologically based computational model for the hypothalamic-pituitary-thyroid (HPT) axis in Xenopus laevis larvae. MATHEMATICAL BIOSCIENCES. Elsevier Science Ltd, New York, NY, USA, 362: 109021, (2023).

Severe thyroid hormone (TH) deprivation during development impairs neurogenesis throughout the brain. The hippocampus also maintains a capacity for neurogenesis throughout life which is reduced in adult-onset hypothyroidism. This study examined hippocampal volume in the neonate and adult hippocampal neurogenesis after developmental and adult-onset TH insufficiency. Pregnant rat dams were administered 0, 3, or 10 ppm of propylthiouracil (PTU) via drinking water from gestational day (GD) 6 until weaning. PTU at the high dose reduced body, brain, hippocampal weights on postnatal day (PN) 14, 21 and 78. Sub-regional analysis revealed decrements in hippocampal volumes at 10 but not 3 ppm PTU on PN23. In Experiment 2, one pair of adult male offspring of 0 and 3ppm-teated dams was placed on 3 ppm PTU from PN60, while a 2nd pair remained on control water. Adult neurogenesis was assessed by bromodeoxyuridine (BrdU, 50mg/kg, ip, 2X daily, X5 days) starting on PN90. Brains from animals perfused 1 and 28 days later were processed for immunohistochemistry. Although no volume changes were seen in neonates at 3ppm, thinning of the granule cell layer emerged in adulthood. Developmental TH insufficiency reduced BrdU+ve cells at 1-day with no further reduction at 28-days post-BrdU, indicative of a selective effect on cell proliferation. This was supported by fewer cells staining for the proliferative marker, Ki67. Adult only PTU did not impair neurogenesis or exacerbate effects seen with developmental exposure. A reduced capacity for neurogenesis may contribute to cognitive deficits evident in adults following moderate degrees of developmental TH insufficiency. This dataset is associated with the following publication: Gilbert, M., J. Goodman, J. Gomez, A. Johnstone, and R. Ramos. Adult Hippocampal Neurogenesis is Impaired by Transient and Moderate Developmental Thyroid Hormone Disruption. TOXICOLOGICAL SCIENCES. Society of Toxicology, 9-21, (2017).

Iodide uptake following a two-hour incubation with concentrations of 5-ATcompared to control iodide uptake in FRTL thyroid follicular cells. This dataset is associated with the following publication: Adams, V., M. Bazar, E. Reinke, A. Buckalew, and W. Eck. In vitro and in vivo effects of 5-Aminotetrazole (5-AT)- an energetic compound. REGULATORY TOXICOLOGY AND PHARMACOLOGY. Elsevier Science Ltd, New York, NY, USA, 111(104573): 1, (2020).

To help determine whether Hg had a causal effect on corticosterone, we investigated the impact of experimental Hg intake on the corticosterone stress response in captive juvenile loons. Juveniles were subjected to three different feeding regimes: 0, 0.4 and 1.2 µg Hg (as MeHgCL)/g wet weight (ww) fish. We then measured baseline and 30 min post-solitary confinement stressor corticosterone concentrations. The data set consists of times of blood draws and dietary Hg levels. Blood samples and data set were provided to the senior author for analysis.

To help determine whether Hg had a causal effect on corticosterone, we investigated the impact of experimental Hg intake on the corticosterone stress response in captive juvenile loons. Juveniles were subjected to three different feeding regimes: 0, 0.4 and 1.2 µg Hg (as MeHgCL)/g wet weight (ww) fish. We then measured baseline and 30 min post-solitary confinement stressor corticosterone concentrations. The data set consists of times of blood draws and dietary Hg levels. Blood samples and data set were provided to the senior author for analysis.