Cold-induced changes in thyroid function in a poikilothermic mammal, the naked mole-rat

2001 ◽  
Vol 280 (1) ◽  
pp. R149-R155 ◽  
Author(s):  
Rochelle Buffenstein ◽  
Ryan Woodley ◽  
Cleopatra Thomadakis ◽  
T. Joseph M. Daly ◽  
David A. Gray
Keyword(s):  
Thyroid Function ◽  
Secretory Activity ◽  
Thyroid Stimulating Hormone ◽  
Thyroid Status ◽  
Cell Height ◽  
Mole Rat ◽  
Naked Mole Rat ◽  
Order Of Magnitude ◽  
Induced Changes ◽  
Tsh Levels

Cold acclimation induces very divergent responses in thyroid function in reptiles and mammals reflective of their different thermoregulatory modes. Naked mole-rats, unlike other small mammals, are unable to effectively employ endothermy and are operatively poikilotherms. We therefore investigated changes in their thyroid status with chronic cold exposure. Under simulated burrow conditions, free thyroxine (T4; 0.39 ± 0.09 ng/dl) and thyroid stimulating hormone (TSH; 1.12 ± 0.56 μIU/ml) levels fell within the reptilian range, one order of magnitude lower than mammalian levels. However, cold induced typical mammalian responses: free T4levels (0.55 ± 0.09 ng/dl) and thyroid follicular cell height were significantly greater. Although TSH levels (1.28 ± 0.83 μIU/ml) were not significantly elevated, thyrotrophs exhibited ultrastructural signs of increased secretory activity. Low thyroid hormone concentrations may contribute substantially to the unusual thermoregulatory mode exhibited by naked mole-rats.

scholarly journals Association of thyroid status with hemoglobin levels in pregnancy

2017 ◽  
Vol 5 (11) ◽  
pp. 4873 ◽  
Author(s):  
Manisha Baghel ◽  
Jyoti Batra ◽  
Thimmaraju K. V. ◽  
Maliyanar Itagappa
Keyword(s):  
Early Diagnosis ◽  
Pregnant Women ◽  
Thyroid Function ◽  
First Trimester ◽  
Thyroid Stimulating Hormone ◽  
Obstetrics And Gynecology ◽  
Thyroid Status ◽  
Thyroid Profile ◽  
Tsh Levels ◽  
In Pregnancy

Background: The association of hemoglobin levels with thyroid status in pregnancy was not studied in detail. Therefore, in this study, we assessed the levels of hemoglobin, thyroid function and its association with hemoglobin levels in first trimester of pregnancy.Methods: Fifty pregnant women who didn’t start any supplementation were recruited from the obstetrics and gynecology outpatient department. Fifty age matched controls were recruited from the residents and staff of the hospital.  Thyroid profile and hemoglobin levels were measured in both the groups. The association was seen between hemoglobin levels and thyroid stimulating hormone (TSH) levels.Results: The hemoglobin levels are significantly low in first trimester pregnant women. Further, the increased TSH levels are negatively correlated with low hemoglobin levels.Conclusions: Screening of hemoglobin levels in first trimester itself will be beneficial to prevent the complications of pregnancy. Further, hypothyroidism also present and associated with reduced hemoglobin. So, early diagnosis of these deficiencies will be useful to start giving supplements to avoid unwanted effects in pregnancy.

scholarly journals Association between ultrasonography echogenicity and heterogeneity and thyroid function in autoimmune diffuse thyroid diseases in children and adolescents 

2021 ◽  
Author(s):  
Ji Eun Park ◽  
Sook Min Hwang ◽  
Ji-Young Hwang ◽  
Jin Hee Moon ◽  
Ik Yang ◽  
...  
Keyword(s):  
Thyroid Function ◽  
Thyroid Dysfunction ◽  
Thyroid Stimulating Hormone ◽  
Thyroid Diseases ◽  
Overt Hypothyroidism ◽  
Thyroid Ultrasound ◽  
Thyroid Status ◽  
Children And Adolescent ◽  
Overt Hyperthyroidism

Abstract Purpose: To evaluate the association between thyroid echogenicity and heterogeneity seen on ultrasonography (US) and thyroid function in pediatric and adolescent populations with autoimmune diffuse thyroid diseases (AITD).Methods: From 2000 to 2020, we reviewed thyroid ultrasound (US) images and thyroid function statuses in 133 children and adolescent AITD patients. Our review of the images focused on decreased echogenicity and heterogeneity, which were classified into four grades.Results: Among patients with overt hypothyroidism or overt hyperthyroidism, 94.2% (65/69) showed a US grade of 3 or 4. In patients with subclinical hyper/hypothyroidism or euthyroidism, 45.3% (29/64) showed grades 1 or 2. There were no overt hyper/hypothyroidism patients with US grade 1. When we compared US grades according to thyroid status, more severe thyroid dysfunction was significantly associated with higher US grade (p=0.047). Thyroid stimulating hormone (TSH) level differed significantly according to US grades when we evaluated hyperthyroid (p=0.035) and hypothyroid (p=0.027) states independently. 11 patients showed both US grade and thyroid function status changes on follow-up US.Conclusions: In children and adolescent AITD patients, there was an association between decreased echogenicity and heterogeneity on US and thyroid dysfunction.

scholarly journals Obese patients with higher TSH levels had an obvious metabolic improvement after bariatric surgery

2021 ◽  
Vol 10 (10) ◽  
pp. 1326-1336
Author(s):  
Nannan Bian ◽  
Xiaomeng Sun ◽  
Biao Zhou ◽  
Lin Zhang ◽  
Qiu Wang ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Bariatric Surgery ◽  
Thyroid Function ◽  
Fasting Blood Glucose ◽  
Thyroid Stimulating Hormone ◽  
Morbidly Obese ◽  
Obese Patients ◽  
Free Triiodothyronine ◽  
The Relationship ◽  
Tsh Levels

Objective Bariatric surgery has become the most effective treatment for morbid obesity. Increasing evidence showed that bariatric surgery can alleviate insulin resistance and influence thyroid function. This study aimed to investigate the relationship between changes in thyroid function and adipose tissue insulin resistance (adipo-IR) after bariatric surgery. Methods A total of 287 non-diabetic participants with regular thyroid function were recruited and divided into the lean, overweight and obese groups. Among them, 50 morbidly obese patients submitted to bariatric surgery. Results The obese group had a higher level of adipo-IR, thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), FT3/free thyroxine (FT4) and metabolism disorders than the lean and overweight groups. BMI was correlated with TSH, FT3, FT3/FT4 and adipo-IR (r = 0.309, 0.315, 0.322 and 0.651, respectively, all P < 0.001). Adipo-IR was significantly correlated with TSH (r = 0.402, P < 0.001), FT3 (r = 0.309, P < 0.001), and FT3/FT4 (r = 0.228, P < 0.05). Bariatric surgery resulted in a sharp decline in BMI, adipo-IR, TSH, FT3 and FT3/FT4 levels, meanwhile, metabolic disorders improved. The decrease in BMI after bariatric surgery was significantly correlated with reductions in adipo-IR (r = 0.577, P < 0.001) and TSH (r = 0.401, P = 0.005). Interestingly, the fasting blood glucose, fasting insulin, adipo-IR and TSH in the higher TSH group decreased more remarkably than in the lower TSH group. Conclusion Obese individuals with higher TSH levels had an obvious metabolic improvement after bariatric surgery.

EFFECT OF THYROID STATUS ON THE THYROTROPHIN-RELEASING HORMONE-DEGRADING ACTIVITY OF RAT SERUM

1976 ◽  
Vol 71 (1) ◽  
pp. 13-19 ◽  
Author(s):  
N. WHITE ◽  
S. L. JEFFCOATE ◽  
E. C. GRIFFITHS ◽  
K. C. HOOPER
Keyword(s):  
Thyroid Hormone ◽  
Human Serum ◽  
Thyroid Function ◽  
Thyroid Status ◽  
Rat Serum ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
Tsh Levels

SUMMARY The TRH-degrading activity of rat serum in vitro is five times more potent than that of human serum. In rats, it is significantly reduced in hypothyroidism (thiouracil-induced) and significantly increased in hyperthyroidism (T3 or T4-induced). This suggests a possible role in the regulation of adenohypophysial-thyroid function which is probably, in turn, dependent on thyroid hormone, rather than TSH, levels.

scholarly journals Abnormal Thyroid Function and Recurrent Pregnancy Loss

2014 ◽  
Vol 9 (1) ◽  
pp. 29-32
Author(s):  
A Shrestha ◽  
CD Chawla
Keyword(s):  
Longitudinal Study ◽  
Thyroid Function ◽  
Autoimmune Thyroiditis ◽  
Pregnancy Loss ◽  
Recurrent Pregnancy Loss ◽  
Thyroid Stimulating Hormone ◽  
Thyroid Disorder ◽  
Positive Message ◽  
Effect Of Treatment ◽  
Tsh Levels

Aims: The aim of our study was to observe the benefit of screening for thyroid function amongst women with recurrent pregnancy loss and effect of treatment for thyroid disorder on pregnancy outcome. Methods: This was a longitudinal study conducted from June 2012 to December 2013. One hundred and three patients with recurrent pregnancy loss without features of thyroid disorder were included. They were investigated for thyroid stimulating hormone (TSH), free tri iodothyronin (FT3), free thyroxine (FT4) levels and for auto-antibodies against thyroperoxidase (anti TPO). The patients with abnormal TSH levels were treated with thyroxine depending on the level of TSH. Results: TSH, FT3, FT4 and anti TPO levels were measured. Amongst 103 ladies, thirty-eight (36.89%) had high levels of TSH. Thirty-five (33.98%) of them underwent test for anti TPO, of which two (5.71%) had autoimmune thyroiditis. Nine (8.73%) out of 103 had high FT4 levels. Ladies with diagnosis of hypothyroidism underwent treatment and 17 (44.73%) out of 38 had conceived. Conclusions: Of 103 women with recurrent pregnancy loss, abnormal thyroid function was detected in 47. Seventeen (44.73%) of them with increased TSH level conceived after treatment with thyroxine, which gives a positive message that hypothyroidism is a treatable cause for recurrent pregnancy loss. DOI: http://dx.doi.org/10.3126/njog.v9i1.11184 NJOG 2014 Jan-Jun; 2(1):29-32

THYROID FUNCTION TESTS IN ADULTS WITH DOWN'S SYNDROME

1978 ◽  
Vol 88 (1) ◽  
pp. 48-54 ◽  
Author(s):  
S. Korsager ◽  
E. M. Chatham ◽  
H. P. Østergaard Kristensen
Keyword(s):  
Thyroid Function ◽  
Down's Syndrome ◽  
Clinical Signs ◽  
Down’S Syndrome ◽  
Thyroid Stimulating Hormone ◽  
Thyroid Function Tests ◽  
Thyroid Status ◽  
Biochemical Tests ◽  
Old Patients ◽  
Function Tests

ABSTRACT Thyroid status was studied in 24 patients above the age of 40 years with Down's syndrome. Three patients had thyroid function tests indicating hypothyroidism. Eight patients had thyroid autoantibodies in serum and 8 patients had a higher than normal level of thyroid stimulating hormone in serum. None of the patients had figures indicating thyrotoxicosis. None of the patients showed any of the clinical signs usually seen in patients with hypothyroidism. It is concluded that biochemical tests indicating hypothyroidism are much more often seen in patients with Down's syndrome than in normal subjects and that thyroid status should be assessed in old patients with this disease.

Hypothyroidism following Treatment for Head and Neck Cancer

1981 ◽  
Vol 90 (5) ◽  
pp. 449-453 ◽  
Author(s):  
Donald P. Vrabec ◽  
Timothy J. Heffron
Keyword(s):  
Radiation Therapy ◽  
Head And Neck ◽  
Thyroid Function ◽  
Elevated Serum ◽  
Thyroid Stimulating Hormone ◽  
Primary Hypothyroidism ◽  
Overt Hypothyroidism ◽  
Patient Will ◽  
Effects Of Radiation ◽  
Tsh Levels

One hundred ninety-six head and neck patients were studied to determine the effects of radiation therapy and surgery on thyroid function. Serum thyroid-stimulating hormone (TSH) levels were obtained as a screening test for primary hypothyroidism. Elevated TSH levels were found in 57 of the 196 patients (29.1%). The highest incidence of abnormal TSH values (66%) occurred in the group treated with combination radiation therapy and surgery, including partial thyroidectomy. TSH levels rose early in the posttreatment period with 60% of the abnormal values occurring within the first three posttreatment years. Posttreatment thyroid dysfunction was twice as common in women (48.6%) as in men (25.4%). When serum thyroxine levels by radioimmunoassay (T4RIA) were correlated with the elevated serum TSH levels, a similar pattern was seen with 65% of the patients in Group 3 having a decreased T4RIA level indicating overt hypothyroidism. Pretreatment levels of thyroid function including thyroid antibody studies should be established for all patients. Serial TSH levels should be done every three months during the first three posttreatment years and semiannually thereafter as long as the patient will return for follow-up care. All patients treated with combination radiation therapy and surgery who develop elevated TSH levels should be treated with thyroid replacement therapy. Patients receiving radiation therapy alone should receive replacement thyroid therapy if they develop a depressed T4RIA value or a pattern of gradually increasing TSH levels.

Altitude-induced changes in plasma thyroxine, 3,5,3'-triiodothyronine, and thyrotropin in rats

1982 ◽  
Vol 53 (2) ◽  
pp. 313-315 ◽  
Author(s):  
J. M. Connors ◽  
L. G. Martin
Keyword(s):  
High Altitude ◽  
Thyroid Function ◽  
Plasma Concentrations ◽  
Thyroid Tissue ◽  
Severe Hypoxia ◽  
Elevated Plasma ◽  
Altitude Exposure ◽  
Thyroid Secretion ◽  
Induced Changes ◽  
Tsh Levels

We have studied the thyroid function of high-altitude-acclimated (6,900 m for 5 wk) and nonaltitude-acclimated control (198 m) rats. After 5 wk of high-altitude exposure the plasma concentrations of both thyroxine (T4) and triiodothyronine (T3) were lower than those in control rats (4.7 +/- 0.3 vs. 3.3 +/- 0.2 microgram/dl and 96 +/- 5 vs. 74 +/- 6 ng/dl, respectively). The plasma thyrotropin (TSH) concentration was elevated in the high-altitude-acclimated rats compared with controls (52 +/- 4 vs. 29 +/- 3 micrograms/dl, respectively). Gross anatomical (thyroid wt/body wt) and histological observations of thyroid tissue were consistent with elevated plasma TSH concentrations. These results suggest that the fall in the plasma concentrations of T4 and T3 during acclimation to severe hypoxia is due to a primary block of thyroid secretion and not to a fall in plasma TSH levels.

scholarly journals Age and Menopausal Status Affect Osteoprotegerin and Osteocalcin Levels in Women Differently, Irrespective of Thyroid Function

2014 ◽  
Vol 7 ◽  
pp. CMED.S15466 ◽  
Author(s):  
Alexander D. Shinkov ◽  
Anna-Maria I. Borissova ◽  
Roussanka D. Kovatcheva ◽  
lliana B. Atanassova ◽  
Jordan D. Vlahov ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Thyroid Function ◽  
Vascular Function ◽  
Thyroid Dysfunction ◽  
Bone Cells ◽  
Menopausal Status ◽  
Thyroid Stimulating Hormone ◽  
Multiple Factors ◽  
Serum Tsh ◽  
Tsh Levels

Osteoprotegerin (OPG) and osteocalcin (OC) are essential bone proteins. Recent studies have demonstrated that they are not secreted solely by bone cells; they play roles in the vascular function and energy metabolism, and they are influenced by multiple factors. The aim of the current study was to investigate the influence of menopause and age on OPG and OC in women with different thyroid-stimulating hormone (TSH) levels. Material and Methods We studied 49 women with elevated TSH, 26 with suppressed TSH, and 67 age-matched euthyroid controls. Of them 64 were menstruating and 78 postmenopausal. Body weight, height, waist circumference (WC), body mass index (BMI), serum TSH, free thyroxin (FT4), OPG, and OC were measured. Results Generally, both OPG and OC were higher in the postmenopausal women than in the menstruating subjects (OPG 3.85 ± 1.49 pmol/L vs. 5.84 ± 2.42 pmol/L, P < 0.001; OC 8.84 ± 3.70 ng/dL vs. 12.87 ± 6.45 ng/dL, P < 0.001), and within the two thyroid dysfunction subgroups and the controls (all P < 0.05). OPG correlated with age (postmenopausal rho = 0.57, P < 0.001; premenopausal rho = 0.31, P = 0.015). Among the premenopausal subjects, OPG was higher in those with low TSH than in the controls ( P = 0.048). OC correlated negatively with BMI and WC in the postmenopausal group (Spearman rho = –-0.25, P = 0.03 and rho = –-0.42, P < 0.001 respectively). OC was higher in the postmenopausal subjects with low TSH than in those with elevated TSH ( P = 0.024), and correlated positively with FT4 (rho = 0.40, P = 0.002) and negatively with TSH (rho = -0.29, P = 0.013). CONCLUSIONS In women, OPG and OC depended differently on age and menopause and, to a lesser extent, on the thyroid function and body composition.

scholarly journals Effects of a Single Venous Dose of Zinc on Thyroid Status in Healthy Individuals and Patients With Graves' Disease

2000 ◽  
Vol 7 (3) ◽  
pp. 151-155 ◽  
Author(s):  
Lubna Farooqi ◽  
Gláucia M. F. S. Mazeto ◽  
Tadao Shuhama ◽  
José Brandão-Neto
Keyword(s):  
Thyroid Function ◽  
Plasma Levels ◽  
Thyroid Stimulating Hormone ◽  
Graves Disease ◽  
Zinc Metabolism ◽  
Healthy Individuals ◽  
Free Triiodothyronine ◽  
Hormone Synthesis ◽  
Hyperthyroid Patients ◽  
Tsh Levels

Zinc metabolism may regulate thyroid function acting at TRH (thyrotropin-releasing hormone) synthesis, peripheral deiodination of T4 (tetraiodothyronine), and binding of thyroid hormones to nuclear receptors. The aim of this study was to investigate the effect of acute zinc administration on TSH (thyroid-stimulating hormone), FT3 (free triiodothyronine), and FT4 (free tetraiodothyronine) in 10 healthy individuals and 12 hyperthyroid patients with Graves' disease. All these individuals were studied following 25 mg Zn++ administered intravenously, at 7:00 a.m. after 12 h fast. Blood samples collected at 0, 3, 30, 60, 90, and 120 min after zinc administration showed no significant alteration in the plasma levels of TSH, FT3, and FT4 in hyperthyroid patients. There were no changes in the plasma levels of FT3 and FT4 in the control subjects, but TSH levels were acutely depressed by zinc administration. This study suggests that zinc given acutely and in pharmacological doses does not affect thyroid function in hyperthyroid subjects, but affect plasma TSH levels in healthy individuals.

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