Kinetic tracer studies show that thyroid hormones are transported into target tissues by stereospecific, high-affinity, low-capacity transporters, both in animals and humans. The K(d) of binding to the transporter varies within the nanomolar range. The different thyroid hormones (T(4), T(3), and rT(3)) are transported via different transporters, except in the pituitary, where they share the same transporter. The molecular mass of the transport proteins varies between 52 and 65kDa. The transport mechanisms are dependent on the energy charge of the cell and -- often -- the sodium gradient over the plasma membrane. A relationship exists with the transport systems of the aromatic amino acids. In non-thyroidal illness and starvation T(4) transport into T(3)-producing tissues is decreased, resulting in a low plasma T(3) concentration, by some considered to be an energy saving mechanism in situations of stress.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.beem.2007.03.007 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Type 3 deiodinase activation mediated by the Shh/Gli1 axis promotes sepsis-induced metabolic dysregulation in skeletal muscles.
Burns Trauma
January 2025
Department of Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, No. 321 Zhongshan Road, Gulou District, Nanjing, Jiangsu 210008, China.
Background: Non-thyroidal illness syndrome is commonly observed in critically ill patients, characterized by the inactivation of systemic thyroid hormones (TH), which aggravates metabolic dysfunction. Recent evidence indicates that enhanced TH inactivation is mediated by the reactivation of type 3 deiodinase (Dio3) at the tissue level, culminating in a perturbed local metabolic equilibrium. This study assessed whether targeted inhibition of Dio3 can maintain tissue metabolic homeostasis under septic conditions and explored the mechanism behind Dio3 reactivation.
View Article and Find Full Text PDFLong-Term Impacts of COVID-19 on Thyroid Health: Insights From Clinical Studies.
Cureus
October 2024
Department of Medicine, Rajeev Gandhi University of Health Sciences, Bengaluru, IND.
Background: COVID-19 emerged in December 2019 and rapidly became a global pandemic. It has since been associated with the progression of various endocrine disorders, including thyroid disease. The long-term effects of this interplay have yet to be explored.
View Article and Find Full Text PDFAssociation of COVID-19 with thyroid dysfunction and autoimmune thyroid disease: A retrospective cohort study.
J Transl Autoimmun
December 2024
Department of Nuclear Medicine, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaan Xi Province, 710004, China.
Background: Since the end of the COVID-19 pandemic, the potential roles of thyroid-inflammatory derangements in driving or being associated with the prognosis of COVID-19 remain controversial. We aimed to clarify the association between COVID-19 infection and thyroid dysfunction, and highlight the impacts of subsequent autoimmune thyroid disease (AITD) on the prognosis of COVID-19.
Methods: The retrospective, multicenter, cohort study enrolled 2,339 participants with COVID-19 from three hospitals located in the north, middle, and south regions of Shaan Xi Province, China, between December 2022 and July 2023.
Relationship between thyroid function and lipid atherogenic profile in pediatric patients with multisystem inflammatory syndrome associated with COVID-19.
Front Pediatr
October 2024
Pediatric Department, "Vittore Buzzi" Children's Hospital, Milano, Italy.
Introduction: Concurrent alterations in the metabolic profile and thyroid dysfunction, including non-thyroidal illness syndrome (NTIS) has been reported in multisystem inflammatory syndrome in children (MIS-C). Considering the influence of thyroid hormones (TH) on lipid metabolism, we explored the relationship between thyroid function and the atherogenic lipid profile in children with MIS-C at admission and during a 12-month follow-up.
Patients And Methods: we considered children admitted for MIS-C.
Evaluation of a laboratory reflex testing protocol to detect hypopituitarism in primary care presenting as hypothyroxinaemia.
Ann Clin Biochem
November 2024
Department of Chemical Pathology, Tallaght University Hospital, Dublin, Ireland.
Background: Thyroid function tests (TFTs) are routinely requested by general practitioners (GPs) in the clinical biochemistry laboratory. Hypothyroxinaemia (low fT4) accompanied by TSH within the reference interval (RI) is a discordant pattern which is seen commonly in non-thyroidal illness and also as result of medications. Hypopituitarism is a lot rarer, but a serious condition the laboratory does not want to miss.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!