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Journal of Veterinary Internal Medicine Nov 2021Hyperthyroid cats might have a predisposition to arterial thrombus formation. The mechanism for thrombogenesis currently is unknown but could be associated with systemic...
BACKGROUND
Hyperthyroid cats might have a predisposition to arterial thrombus formation. The mechanism for thrombogenesis currently is unknown but could be associated with systemic hypercoagulability as seen in hyperthyroid humans.
OBJECTIVE
Our purpose was to evaluate markers of hemostasis in hyperthyroid cats compared to healthy cats, and in hyperthyroid cats before and after radioactive iodine treatment (RIT).
ANIMALS
Twenty-five cats with hyperthyroidism and 13 healthy euthyroid cats >8 years of age.
METHODS
Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration, antithrombin (AT), D-dimers, thrombin-antithrombin complexes (TAT), von Willebrand Factor antigen (vWF : Ag), and activity of factors VIII and IX were measured. An echocardiogram was performed in all cats. Hemostatic markers and echocardiogram were evaluated again 6 to 9 months after successful RIT in 7 cats.
RESULTS
Hyperthyroid cats had higher fibrinogen concentration (P < .0001), AT activity (P < .0001), and vWF : Ag concentration (P = .01) than healthy control cats with all results decreasing significantly post-RIT. Hyperthyroid cats were not more likely to be in a hypercoaguable state than euthyroid cats (P = .08). Serum T4 concentration was not a predictor of a hypercoagulable state (P = .53).
CONCLUSIONS AND CLINICAL IMPORTANCE
Hyperthyroid cats have evidence of altered hemostasis that does not appear to be solely attributable to cardiac abnormalities, but no evidence of a hypercoagulable state. Findings suggest altered hemostasis resolves after RIT. Hyperthyroid cats could have endothelial dysfunction as indicated by increased vWF : Ag which could potentiate thrombogenesis.
Topics: Animals; Blood Coagulation Tests; Cat Diseases; Cats; Hemostasis; Hyperthyroidism; Iodine Radioisotopes; Thyroid Neoplasms
PubMed: 34590754
DOI: 10.1111/jvim.16274 -
Cellular and Molecular Life Sciences :... Feb 2006Hypermetabolic state in hyperthyroidism is associated with tissue oxidative injury. Available data indicate that hyperthyroid tissues exhibit an increased ROS and RNS... (Review)
Review
Hypermetabolic state in hyperthyroidism is associated with tissue oxidative injury. Available data indicate that hyperthyroid tissues exhibit an increased ROS and RNS production. The increased mitochondrial ROS generation is a side effect of the enhanced level of electron carriers, by which hyperthyroid tissues increase their metabolic capacity. Investigations of antioxidant defence system have returned controversial results. Moreover, other thyroid hormone-linked biochemical changes increase tissue susceptibility to oxidative challenge, which exacerbates the injury and dysfunction they suffer under stressful conditions. Mitochondria, as a primary target for oxidative stress, might account for hyperthyroidism linked tissue dysfunction. This is consistent with the inverse relationship found between functional recovery of ischemic hyperthyroid hearts and mitochondrial oxidative damage and respiration impairment. However, thyroid hormone-activated mitochondrial mechanisms provide protection against excessive tissue dysfunction, including increased expression of uncoupling proteins, proteolytic enzymes and transcriptional coactivator PGC-1, and stimulate opening of permeability transition pores.
Topics: Animals; Heart; Humans; Hyperthyroidism; Lipid Peroxidation; Liver; Mitochondria; Muscle, Skeletal; Myocardium; Oxidative Stress; Reactive Nitrogen Species; Reactive Oxygen Species; Thyroid Hormones
PubMed: 16389448
DOI: 10.1007/s00018-005-5457-9 -
Endocrine Journal Mar 2022Thyroid hormones are critical regulators of vertebrate development and metabolism. Under hyperthyroid conditions, excess thyroid hormones induce expression of several...
Thyroid hormones are critical regulators of vertebrate development and metabolism. Under hyperthyroid conditions, excess thyroid hormones induce expression of several enzymes and activities via activation of ligand-bound thyroid hormone receptors (TRs). Arginase (ARG) is downstream of a ligand-bound TR and overexpression of ARG2 induces the production of reactive oxygen species and subsequent exacerbation of kidney ischemia/reperfusion (I/R) injury. To clarify the association between I/R-induced kidney injury and hyperthyroidism, mice were pretreated with L-thyroxine (LT4) or vehicle alone, then subjected to I/R. Proximal tubular cell-specific conditional knockout of thyroid hormone receptor β (TRβcKO) mice was generated and the effects of I/R were analyzed. Hyperthyroidism enhanced tubular damage and fibrosis in the kidneys of mice after I/R. Hyperthyroidism induced tubular cell necroptosis following inflammatory cell accumulation in the kidney after I/R. ARG2 expressions and reactive oxygen species accumulated in the kidneys of hyperthyroid mice after I/R, but these changes were ameliorated in the kidneys of TRβcKO mice. Hyperthyroidism-enhanced kidney injury was ameliorated in the kidney of TRβcKO mice after I/R. These results suggest that excess thyroid hormones are disadvantageous for the kidney under ischemic stress. Overt hypothyroidism represents a severe thyroid hormone deficiency disease that requires LT4 treatment, while overreplacement or iatrogenic thyrotoxicosis might cause kidney injury.
Topics: Animals; Hyperthyroidism; Hypothyroidism; Kidney; Mice; Reperfusion Injury; Thyroid Hormones
PubMed: 34629337
DOI: 10.1507/endocrj.EJ21-0395 -
Frontiers in Endocrinology 2023Iodine is essential in thyroid hormone production. Iodine deficiency is associated with serious complications (i.e miscarriage and stillbirth), whereas excess can cause...
OBJECTIVE
Iodine is essential in thyroid hormone production. Iodine deficiency is associated with serious complications (i.e miscarriage and stillbirth), whereas excess can cause thyroid dysfunction (i.e hyperthyroidism, hypothyroidism, thyroid autoimmunity). We conducted this scientometric study to visualize hot spots and trends in iodine-induced thyroid dysfunction over past two decades. The aim of this paper was to help scholars quickly understand the development and potential trend in this field, and guide future research directions.
METHODS
Articles on iodine-induced thyroid dysfunction from 2000 to 2022 were retrieved from the Web of Science Core Collection (WoSCC) using the following search terms: (((((TS=(hypothyroid*)) OR TS=(hyperthyroid*)) OR TS= ("TSH deficiency")) OR TS= ("thyroid stimulating hormone deficiency")) AND TS=(Iodine)) NOT TS=(radioiodine). Only publications in English were selected. CiteSpace, VOSviewer, Tableau, Carrot2, and R software were used to analyze the contribution and co-occurrence relationships of different countries, institutes, keywords, references, and journals.
RESULTS
A total of 2986 publications from 115 countries and 3412 research institutions were included. From 2000 to 2022, research on iodine-induced thyroid dysfunction progressed over a three-stage development period: initial development (2000-2009), stable development (2010-2016), and rapid development (2016-2022) period. The had the most co-citations followed and China Medical University (n=76) had the most publications. The top three clusters of co-citation references were isolated maternal hypothyroxinemia, subclinical hyperthyroidism, and brain development. Various scientific methods were applied to reveal acknowledge structure, development trend and research hotspots in iodine-induced thyroid dysfunction.
CONCLUSION
Our scientometric analysis shows that investigations related to pregnant women, epidemiology surveys, and iodine deficiency are promising topics for future iodine-induced thyroid dysfunction research and highlights the important role of iodine on thyroid function.
Topics: Pregnancy; Female; Humans; Iodine; Iodine Radioisotopes; Hypothyroidism; Hyperthyroidism; Malnutrition
PubMed: 37800143
DOI: 10.3389/fendo.2023.1239038 -
PloS One 2013Hyperthyroidism has been linked with different morbidities, like atrial fibrillation, stroke and diabetes mellitus. However, our knowledge regarding the extent and... (Observational Study)
Observational Study
BACKGROUND
Hyperthyroidism has been linked with different morbidities, like atrial fibrillation, stroke and diabetes mellitus. However, our knowledge regarding the extent and temporal relation between hyperthyroidism and other diseases is fragmented. Here, we aimed at evaluating various morbidities before and after the diagnosis of hyperthyroidism.
METHODS
Observational cohort study. From nationwide Danish health registers 2631 hyperthyroid singletons and 375 twin pairs discordant for hyperthyroidism were identified and followed for an average of 6 years (range 0-13). Data on the occurrence of cardiovascular diseases, lung diseases, diabetes mellitus, rheumatic diseases and malignant diseases was obtained by person-to-person record linkage with the National Danish Patient Register and/or the Danish National Prescription Registry (lung diseases and diabetes mellitus). Logistic and Cox regression models were used to assess the risk of morbidity before and after the diagnosis of hyperthyroidism, respectively. All Cox regression analyses were adjusted for the degree of co-morbidity preceding the diagnosis of hyperthyroidism, using the Charlson score.
RESULTS
Hyperthyroid individuals had a significantly higher risk of being diagnosed with cardiovascular diseases (odds ratio (OR) 1.65; 95% confidence interval (CI): 1.45-1.87), lung diseases (OR 1.53; 95% CI: 1.29-1.60), and diabetes mellitus (OR 1.43, 95% CI: 1.20-1.72), but not with malignant diseases (OR 1.16, 95% CI: 0.99-1.36) prior to the diagnosis of hyperthyroidism. After the diagnosis of hyperthyroidism, subjects had a significantly higher risk of being diagnosed with cardiovascular diseases (hazard ratio (HR) 1.34; 95% CI: 1.15-1.56), lung diseases (HR 1.28; 95% CI: 1.10-1.49), and diabetes mellitus (HR 1.46; 95% CI: 1.16-1.84), but not with rheumatic diseases (HR 1.39, 95% CI: 0.92-2.09) or malignant diseases (HR 1.18, 95% CI 0.97-1.42).
CONCLUSIONS
We demonstrate a significantly increased burden of morbidity, both before and after the diagnosis of hyperthyroidism.
Topics: Aged; Cardiovascular Diseases; Cohort Studies; Denmark; Diabetes Mellitus; Female; Humans; Hyperthyroidism; Logistic Models; Lung Diseases; Male; Middle Aged; Morbidity; Proportional Hazards Models; Registries; Time Factors
PubMed: 23818961
DOI: 10.1371/journal.pone.0066711 -
The Journal of Clinical Endocrinology... Mar 2022Neuropsychiatric symptoms are common features of Graves disease (GD) in hyperthyroidism and after treatment. The mechanism behind these symptoms is unknown, but reduced...
CONTEXT
Neuropsychiatric symptoms are common features of Graves disease (GD) in hyperthyroidism and after treatment. The mechanism behind these symptoms is unknown, but reduced hippocampal volumes have been observed in association with increased thyroid hormone levels.
OBJECTIVE
This work aimed at investigating GD influence on regional medial temporal lobe (MTL) volumes.
METHODS
Sixty-two women with newly diagnosed GD underwent assessment including magnetic resonance (MR) imaging in hyperthyroidism and 48 of them were followed up after a mean of 16.4 ± 4.2 SD months of treatment. Matched thyroid-healthy controls were also assessed twice at a 15-month interval. MR images were automatically segmented using multiatlas propagation with enhanced registration. Regional medial temporal lobe (MTL) volumes for amygdalae and hippocampi were compared with clinical data and data from symptom questionnaires and neuropsychological tests.
RESULTS
Patients had smaller MTL regions than controls at inclusion. At follow-up, all 4 MTL regions had increased volumes and only the volume of the left amygdala remained reduced compared to controls. There were significant correlations between the level of thyrotropin receptor antibodies (TRAb) and MTL volumes at inclusion and also between the longitudinal difference in the levels of free 3,5,3'-triiodothyronine and TRAb and the difference in MTL volumes. There were no significant correlations between symptoms or test scores and any of the 4 MTL volumes.
CONCLUSION
Dynamic alterations in the amygdalae and hippocampi in GD reflect a previously unknown level of brain involvement both in the hyperthyroid state of the condition and after treatment. The clinical significance, as well as the mechanisms behind these novel findings, warrant further study of the neurological consequences of GD.
Topics: Female; Graves Disease; Humans; Hyperthyroidism; Immunoglobulins, Thyroid-Stimulating; Longitudinal Studies; Magnetic Resonance Imaging; Temporal Lobe
PubMed: 34752624
DOI: 10.1210/clinem/dgab808 -
Annals of Palliative Medicine Sep 2021This trial aimed to analyze the relationship between hyperthyroidism and the morbidity rate of hypercalcemia in the Xindu district, Chengdu, Sichuan province. We... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
This trial aimed to analyze the relationship between hyperthyroidism and the morbidity rate of hypercalcemia in the Xindu district, Chengdu, Sichuan province. We observed the level of serum calcium, the bone metabolic and thyroid autoimmune-related antibodies index during vitamin D3 treatment combined with traditional antithyroid drugs (ATD).
METHODS
Our research included hyperthyroid patients with a first-time diagnosis of Graves diseases (GD) combined with hypercalcemia on the basis of conventional anti-hyperthyroidism therapy, which were randomized into a vitamin D3 group (vitamin D3, 800-1,200 IU/day) and an ATD group (methimazole, 15-30 mg/day). All hyperthyroidism patients with hypercalcemia were analyzed, and changes in serum calcium (Ca2+), parathyroid hormone (PTH), thyroid function, thyroid autoimmune-related antibodies, and 25-dihydroxyvitamin D (25-OHVit D) levels during treatment of thyrotoxicosis with added vitamin D3 were explored.
RESULTS
In total, 184 patients with hyperthyroidism were observed, including 36 (19.57%) patients associated with hypercalcemia, with an age of onset of (56.39±5.80) years old. Twelve (6.52%) of these 36 cases reported digestive symptoms as the first manifestation, and four (2.17%) patients presented with a hypercalcemia crisis as the first manifestation. Serum Ca2+, free triiodothyronine (FT3), free thyroxine (FT4), and thyrotropin hormone receptor antibody (TRAb) levels increased in patients with hypercalcemia. Following the addition of vitamin D3 treatment, serum Ca2+, FT3, FT4, and TRAb levels were significantly decreased relative to the ATD group, while the thyroid-stimulating hormone (TSH), PTH, and 25-OHVit D levels were normalized.
CONCLUSIONS
Our study highlighted the importance of taking functional digestive disturbance into consideration in hyperthyroidism diagnosis, even in the absence of the typical symptoms. The level of thyroid related antibodies, thyroid function, and bone metabolism in hyperthyroidism patients combined with hypercalcemia could be improved by vitamin D3 adjuvant therapy.
TRIAL REGISTRATION
Chinese Clinical Trial Registry: ChiCTR2100047870.
Topics: Cholecalciferol; Graves Disease; Humans; Hypercalcemia; Hyperthyroidism; Middle Aged; Prevalence
PubMed: 34628889
DOI: 10.21037/apm-21-1947 -
Hormone Research 2006Congenital hyperthyroidism is less frequent than congenital hypothyroidism but its impact on growth and development can be as dramatic. The immune form of... (Review)
Review
Congenital hyperthyroidism is less frequent than congenital hypothyroidism but its impact on growth and development can be as dramatic. The immune form of hyperthyroidism that is transmitted from a mother with Graves' disease to her foetus and then neonate is transient, but cases of persistent congenital hyperthyroidism had also been described, that can now be explained by molecular abnormalities of the thyrotropin receptor. The abundance of published data on the neonatal effects of maternal Graves' disease contrasts with the paucity of information on fetal effects. Recent studies showed that it is of utmost to scrutinize fetal thyroid by expert ultrasonographist and to have a team work with obstetricians and pediatric endocrinologists in pregnant women with Graves' disease. This allowed to accurately determine the fetal thyroid status and to adapt the treatment in the mothers successfully. Fetal hyperthyroidism does exist and needs an appropriate aggressive treatment. Clearly the fetus has become our patient!
Topics: Female; Fetal Diseases; Humans; Hyperthyroidism; Infant, Newborn; Male; Pregnancy
PubMed: 16582565
DOI: 10.1159/000092454 -
Microbial Biotechnology Mar 2022Endothermic mammals have a high energy cost to maintain a stable and high body temperature (T , around 37°C). Thyroid hormones are a major regulator for energy...
Endothermic mammals have a high energy cost to maintain a stable and high body temperature (T , around 37°C). Thyroid hormones are a major regulator for energy metabolism and T . The gut microbiota is involved in modulating host energy metabolism. However, whether the interaction between the gut microbiota and thyroid hormones is involved in metabolic and thermal regulations is unclear. We hypothesized that thyroid hormones via an interaction with gut microbiota orchestrate host thermogenesis and T . l-thyroxine-induced hyperthyroid Mongolian gerbils (Meriones unguiculatus) increased resting metabolic rate (RMR) and T , whereas Methimazole-induced hypothyroid animals decreased RMR. Both hypothyroid and hyperthyroid animals differed significantly in faecal bacterial community. Hyperthyroidism increased the relative abundance of pathogenic bacteria, such as Helicobacter and Rikenella, and decreased abundance of beneficial bacteria Butyricimonas and Parabacteroides, accompanied by reduced total bile acids and short-chain fatty acids. Furthermore, the hyperthyroid gerbils transplanted with the microbiota from control donors increased type 2 deiodinase (DIO2) expression in the liver and showed a greater rate of decline of both serum T3 and T4 levels and, consequently, a more rapid recovery of normal RMR and T . These findings indicate that thyroid hormones regulate thermogenesis depending on gut microbiota and colonization with normal microbiota by caecal microbial transplantation attenuates hyperthyroid-induced thermogenesis. This work reveals the functional consequences of the gut microbiota-thyroid axis in controlling host metabolic physiology and T in endotherms.
Topics: Animals; Cecum; Gerbillinae; Hyperthyroidism; Thermogenesis; Thyroid Hormones
PubMed: 33729663
DOI: 10.1111/1751-7915.13793 -
The Journal of Clinical Endocrinology... Jul 2023Gut bacteria can influence host immune responses but little is known about their role in tolerance-loss mechanisms in Graves disease (GD; hyperthyroidism caused by... (Observational Study)
Observational Study
CONTEXT
Gut bacteria can influence host immune responses but little is known about their role in tolerance-loss mechanisms in Graves disease (GD; hyperthyroidism caused by autoantibodies, TRAb, to the thyrotropin receptor, TSHR) and its progression to Graves orbitopathy (GO).
OBJECTIVE
This work aimed to compare the fecal microbiota in GD patients, with GO of varying severity, and healthy controls (HCs).
METHODS
Patients were recruited from 4 European countries (105 GD patients, 41 HCs) for an observational study with cross-sectional and longitudinal components.
RESULTS
At recruitment, when patients were hyperthyroid and TRAb positive, Actinobacteria were significantly increased and Bacteroidetes significantly decreased in GD/GO compared with HCs. The Firmicutes to Bacteroidetes (F:B) ratio was significantly higher in GD/GO than in HCs. Differential abundance of 15 genera was observed in patients, being most skewed in mild GO. Bacteroides displayed positive and negative correlations with TSH and free thyroxine, respectively, and was also significantly associated with smoking in GO; smoking is a risk factor for GO but not GD. Longitudinal analyses revealed that the presence of certain bacteria (Clostridiales) at diagnosis correlated with the persistence of TRAb more than 200 days after commencing antithyroid drug treatment.
CONCLUSION
The increased F:B ratio observed in GD/GO mirrors our finding in a murine model comparing TSHR-immunized with control mice. We defined a microbiome signature and identified changes associated with autoimmunity as distinct from those due to hyperthyroidism. Persistence of TRAb is predictive of relapse; identification of these patients at diagnosis, via their microbiome, could improve management with potential to eradicate Clostridiales.
Topics: Humans; Mice; Animals; Graves Ophthalmopathy; Indigo Carmine; Gastrointestinal Microbiome; Cross-Sectional Studies; Graves Disease; Autoantibodies; Receptors, Thyrotropin; Hyperthyroidism
PubMed: 36683389
DOI: 10.1210/clinem/dgad030