Recently, oxyfluorfen, a pre- and post-emergent diphenyl ether herbicide, was identified in our laboratory as an inhibitor of iodide uptake by the sodium iodide symporter (NIS), the first key step in the synthesis of thyroid hormones (THs). This inhibition was observed , using both a human NIS engineered cell line (hNIS-HEK293T-EPA) and a rat thyroid follicular cell line (FRTL-5). Oxyfluorfen was found to be a potent inhibitor of NIS activity with an EC50 of approximately 2 µM in both cell lines with no observed cytotoxicity at any concentration tested up to 100 μM. The current research tested the hypothesis that oxyfluorfen alters circulating concentrations of THs. This hypothesis was first tested in a pilot study with both juvenile male and female rats exposed to oxyfluorfen for 4 days at 0, 125, 250 and 500 mg/kg/day. Once we identified that this short-term 4-day oxyfluorfen exposure suppressed both total serum thyroxine (T4) and triiodothyronine (T3) at all doses, we tested seven lower concentrations of oxyfluorfen (0.8125 to 62.5 mg/kg day) in an 8-day exposure paradigm to more closely evaluate the dose-response. We found that oxyfluorfen suppressed serum T4 with a LOEL of 3.25 mg/kg/day and T3 with a LOEL 62.5 mg/kg/day. Analytical chemistry of the serum showed an accumulation over time following oral exposure to oxyfluorfen in both the 4- and 8-day groups. Analytical chemistry of the thyroid glands in the 8-day study revealed higher accumulation in the thyroid as compared to the serum (2 to 3- fold at 62.5 mg/kg). No changes in thyroid weight or serum TSH were observed following the 8-day exposure. This study is the first to demonstrate an effect of oxyfluorfen on serum thyroid hormones in the rat. Additional studies are needed to further evaluate the effects on thyroid homeostasis with extended exposures and the potential implications of the observed effects.
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http://dx.doi.org/10.1016/j.crtox.2023.100146 | DOI Listing |
Ann Med
December 2025
Department of General Surgery, The Affiliated Taizhou People's Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Taizhou, China.
Objective: To comprehensively investigate the predictive value of thyroid hormone sensitivity parameters for cervical lymph node metastasis in patients diagnosed with differentiated thyroid cancer (DTC) undergoing total thyroidectomy and neck lymph node dissection.
Methods: A retrospective cohort study was conducted involving patients diagnosed with DTC and evaluated for cervical lymph node metastasis. Relevant demographic, tumour, lymph node and thyroid hormone sensitivity parameter data were extracted from medical records and laboratory reports.
BMC Res Notes
December 2024
Department of Immunology, Faculty of Medicine, Kazerun Branch, Islamic Azad University, Kazerun, Iran.
Aim: Hypothyroidism is created by disruption of thyroid hormone production, which can destroy the emotional, relational, social, and working life of patients if left untreated. Hypothyroidism has multiple etiologies. We evaluated the relationship of hematological parameters and inflammatory biomarkers with thyroid hormones to find the potential use of these items in patients screening and prognosis.
View Article and Find Full Text PDFBMC Psychiatry
December 2024
Department of Psychiatry, First Affiliated Hospital, Jinan University, Guangzhou, 510630, China.
Background: The clinical characteristics of major depressive disorder (MDD) in adolescents show notable gender-related differences, but the cause of these differences is still not understood. The current research concentrates on the changes in neurometabolism and neuroendocrine function, aiming to identify differences in endocrine function and brain metabolism between male and female adolescents with MDD.
Methods: A total of 121 teenagers diagnosed with MDD (43 males and 78 females) were enlisted as participants.
Sci Rep
December 2024
Department of Endocrine and Metabolism, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China.
The correlation between thyroid hormone (TH) sensitivity and microvascular complications of type 2 diabetes mellitus (T2DM) remains uncertain. This study aimed to explore the association between TH sensitivity and the risk of diabetic kidney disease (DKD), diabetic retinopathy (DR), and diabetic neuropathy (DNP) in euthyroid T2DM patients. This study included a total of 946 hospitalized T2DM patients and calculated their sensitivity to the TH index, and each patient completed screenings for DKD, DR, and DNP.
View Article and Find Full Text PDFSci Rep
December 2024
Division of Paediatric Endocrinology, Vrije Universiteit Brussel, UZ Brussel, Laarbeeklaan 110, Brussels, 1090, Belgium.
Up to 80% of children/adolescents with Graves' disease (GD) may require second-line treatment with either surgery or radioactive iodine (RAI) therapy after treatment with antithyroid drugs. These interventions aim to induce permanent hypothyroidism, but are not always successful. We aimed to evaluate the initial success rate (within the first year) of RAI treatment and its determining factors as second-line treatment in teenagers with GD.
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