Total Triiodothyronine Levels Research Articles

Changes in serum thyroid hormone levels in psychiatric patients treated with second-generation antipsychotics.

The objective of the study was to evaluate changes in serum thyroid hormone levels in psychiatric patients after second-generation antipsychotic (SGA) treatment, and to determine differences between monotherapy and polytherapy with SGAs, as well as differences between patients with and without a history of antipsychotics. A total of 71 patients with baseline thyroid hormone levels within the normal reference ranges were included in this retrospectively study. After SGAs treatment, the serum levels of free triiodothyronine (FT3), free thyroxine (FT4), total triiodothyronine (TT3), and total thyroxine (TT4) significantly decreased, and serum thyroid-stimulating hormone (TSH) levels significantly increased (changes from baseline: FT3: -0.31 pmol/L, p < 0.001; FT4: -2.71 pmol/L, p < 0.001; TT3: -0.05 nmol/L, p = 0.024, TT4: -12.36 nmol/L, p < 0.001; TSH: 0.46 mIU/L, p < 0.001). One (1.4%) patient had TSH levels higher than 7 mIU/L. Changes in serum levels of TSH and TT3 between patients with or without a history of antipsychotic drugs were significantly different (changes from baseline: TSH: p < 0.001 vs. p = 0.089; TT3: p = 0.013 vs. p = 0.553). Changes in serum TSH levels had a moderate positive correlation with the average daily dose of SGAs (p = 0.007, r = 0.318). After SGA treatment, patients seemed to have a trend of hypothyroidism, but the incidence was low. The preliminary results of this study did not show the necessity of regular monitoring of serum thyroid hormone levels in patients with baseline thyroid hormone levels within the normal reference ranges.

Effects of prenatal exposure to five parabens on neonatal thyroid function and birth weight: Evidence from SMBCS study

BackgroundParabens, suspected as endocrine-disrupting chemicals, are nearly ubiquitous in the human body and exposure to these chemicals during pregnancy may disrupt thyroid hormones homeostasis and even affect fetal growth, although the impacts are still unclear. ObjectivesWe aimed to estimate associations of maternal urinary paraben concentrations with cord serum thyroid hormones and birth weight. MethodsA subset of 437 mother-newborn pairs were included from a prospective birth cohort with five parabens quantified in maternal urine and seven thyroid function indicators measured in cord serum samples. Multivariable linear regression models and elastic net regression (ENR) models were applied to explore associations between individual and mixtures of prenatal urinary paraben concentrations and thyroid hormones and birth weight, respectively. ResultsMaternal urinary ethyl-paraben (EtP) concentrations were associated with increased cord serum total triiodothyronine levels (TT3) [percent change: 1.51%; 95% confidence interval (CI): 0.20%, 2.74%; p=0.017]. Urinary propyl-paraben (PrP) levels predicted higher thyroid peroxidase antibodies (percent change: 4.19%, 95%CI: 0.20%, 8.44%; p=0.041). Maternal urinary EtP and butyl-paraben (BuP) concentrations were significantly positively associated with birth weight [regression coefficient, (β)=40.9g, 95%CI: 3.99, 76.6; p=0.030; β=62.1g, 95%CI: 8.70, 115; p=0.023, for EtP and BuP, respectively]. In sex-stratified analyses, positive relationship between EtP levels and birth weight was observed in boys. Urinary EtP concentrations predicted higher TT3 levels in cord serum samples, assessing parabens as a chemical mixture with ENR models. ConclusionsPrenatal exposure to parabens may affect thyroid hormone indicators with increased serum TT3 levels and associate with higher birth weight, especially in boys. The underlying biological mechanisms and effects of prenatal paraben exposures on disruption of thyroid function homeostasis and potential impacts of childhood growth and development needed to be further investigated.

Neurotoxicity and related mechanisms of flame retardant TCEP exposure in mice

Objective: To explore the neurotoxicity and mechanism of tris(2-chloroethyl) phosphate (TCEP) exposure in mice.Methods: Total 30 adult Kunming mice were randomly divided into normal control group (0 mg/kg·d), low-dose TCEP group (10 mg/kg·d), and high-dose TCEP group (100 mg/kg·d), and administered continuously by gavage for 30 days.Results: Compared with the control group, the water intake of high-dose TCEP group was declined significantly (p < 0.05), and the organ index of liver and spleen were increased significantly (p < 0.05). In addition, the escape latency of TCEP exposed mice were longer than that in the control group in water maze test (p < 0.05), while the total swimming course of high-dose TCEP group was elevated and the swimming time in target quadrant was obviously shortened compared with the control group (p < 0.05). The serum levels of total-triiodothyronine (TT3) and free triiodothyronine (FT3) were significantly higher in the high-dose TCEP group than in the control group (p＜0.05). Compared with the control group, the activities of glutathione transferase (GST) and super oxide dismutase (SOD) in the high-dose TCEP group were increased, and GST in the low-dose TCEP group were decreased, while the content of malonaldehyde (MDA) in both groups was increased (p＜0.05). In the CCK8 assay, the viability of PC12 cells decreased with an increase of TCEP concentration, indicating a concentration dependent neurotoxicity.Conclusion: TCEP exposure can cause neurotoxicity by increasing thyroid hormones and inducing oxidative damage in mice.

Change of Rheoreaction and Concentration of Thyroid Hormones in Blood of Juvenile Rainbow Trout Oncorhynchus mykiss during Starvation

Rheoreaction and concentration of thyroid hormones in blood of juvenile rainbow trout Oncorhynchus mykiss is studied during starvation (12 days). It is found that starvation predominantly stimulates downstream migration of fish and decreases the concentration of total triiodothyronine in the blood. The concentration of total triiodothyronine decreases to a lesser degree in fish moving predominantly upstream. The concentrations of free triiodothyronine and total thyroxine do not change during starvation. The level of total triiodothyronine in fish’s blood is an indicator of their migratory activity.

Thyroid status of males with acute infectious pulmonary destruction

The aim of the study was to investigate the indicators of the thyroid status in males with acute infectious pulmonary destruction (AIPD), depending on the disease form and the presence of complications. Material and methods. The serum levels of total triiodothyronine (T3), total thyroxine (T4) and thyroid-stimulating hormone (TSH) were measured by radioimmunoassay in 80 males with AIPD and 30 healthy males volunteers. Results. T3 serum level is decreased in males with AIPD and is not depended on the disease form and complications. T3 serum level reduction is occurred due to decrease of peripheral conversion of thyroid hormones. If AIPD is complicated by sepsis, then T4 production is reduced. T4 serum level correlates with the presence of sepsis in males with AIPD (rS = –0.49; p = 0.000003). The sepsis probability threshold in males with AIPD for value T4 is ≤95.5 nmol/L with a sensitivity of 100 % and a specificity of 62.5 %. Thyroid function remains normal in 25 % (95 % CI: 16–34) of males with AIPD, in other cases it is represented by: primary hypothyroidism – in 11 % (95 % CI: 4–18), nonthyroidal illness syndrome (NTIS) type I – in 44 % (95 % CI: 33–55), NTIS type II – in 11 % (95 % CI: 4–18), NTIS type V – in 9 % (95 % CI: 3–15). NTIS type II is associated with the highest mortality rate (pFisher = 0.0015). T4 serum levels correlate with mortality in males with AIPD (rS = –0.37; p = 0.00082). The mortality probability threshold in males with AIPD for value T4 is ≤70.1 nmol/L with a sensitivity of 68.7 % and a specificity of 78.1 %. The obtained data indicates the advisability of monitoring and analysis of the thyroid status indicators in males with AIPD for the diagnosis of sepsis and prognosis of the disease outcome.

Evaluation of the Effects of Schisandra chinensis on the Myocardium of Rats with Hyperthyroid Heart Disease by Using Velocity Vector Imaging Combined with the Estimation of p53 Expression and Calmodulin Activity.

Schisandra chinensis (SC) is reported to improve myocardial ischemia. Velocity vector imaging (VVI) is a noninvasive technique for evaluating myocardial function in humans, while few reported on the application in animals. In this study, we aimed to evaluate the improved effects of SC on the myocardium of Sprague Dawley rats having hyperthyroid heart disease (HHD) using VVI technique. HHD models were established by injecting daily with subcutaneous levothyroxine (0.5 mg/kg). Then, the SC group was administered the aqueous extract of SC (2 g/kg) once daily, while the HHD and control (CON) groups were administered the same amount of distilled water daily. All the rats were provided the same amount of food and water daily, and the intervention was stopped after 28 days. The efficacy of SC in HHD rats was evaluated by ultrasound VVI. The serum total triiodothyronine level, total thyroxine level, N-terminal pro-brain natriuretic peptide expression, p53 expression, and calmodulin (CaM) activity were assessed by western blotting, Hematoxylin-Eosin and Masson staining, and electron microscopy. The results indicated that SC significantly improved the systolic velocity, diastolic velocity, strain, systolic strain rate, and diastolic strain rate of the heart by significantly reducing p53 expression and CaM activity (P < 0.05), improving myocardial fibrosis in HHD rats. Also, VVI can be a valuable tool for the evaluation of myocardial function in HHD rats.

Thyroid-disrupting effects of chlorpyrifos in female Wistar rats

Thousands of chemicals are released into the environment daily, arousing great scientific interest because they can influence the overall function of living organisms. The indiscriminate use of pesticides, especially organophosphate, confers important risks to both public and environmental health. Previous studies showed that chlorpyrifos (CPF) acts as an endocrine disruptor. Nevertheless, CPF is still widely used in many countries. Thus, we evaluated the thyroid-disrupting effects of CPF after short-term low-dose oral exposure in female Wistar rats. A total of 48 female Wistar rats were divided into five experimental groups (n = 8/group) that were treated orally by gavage with vehicle (control) and chlorpyrifos (0.01, 0.1, 1, and 10 mg/kg) for 5 days. Clinical signs of toxicity were observed throughout treatment. On day 6, the animals were weighed. Serum samples were obtained to measure levels of thyroid hormones, alanine aminotransferase, aspartate aminotransferase, bilirubin, glutamyl transpeptidase, and estradiol. The animals were then euthanized by deep anesthesia with isoflurane. The thyroid gland, liver, spleen, and kidneys were collected to determine relative organ weight and perform histopathological analyses. We observed a significant increase in total triiodothyronine (T3) levels in all CPF treatment groups, even at very low doses that corresponded to the Acceptable Daily Intake. Only the highest dose tested significantly increased both total and free T3 levels. In the group that received the highest dose of CPF, thyroid follicles had irregular contours and few or no colloids. The present results indicated that short-term low-dose CPF exposure in female rats induced significant thyroid-disrupting effects.

Reducing Inappropriate Serum T3 Laboratory Test Ordering in Patients with Treated Hypothyroidism

Objective: Choosing Wisely is a campaign of the American Board of Internal Medicine that aims to promote evidence-based practices to reduce unnecessary ordering of tests or procedures. As part of this campaign, the Endocrine Society advises against ordering a serum total or free triiodothyronine (T3) level when assessing levothyroxine dosing in hypothyroid patients. This study was performed to assess and reduce inappropriate laboratory ordering practices among providers who manage patients with hypothyroidism within a large U.S. academic health system. Methods: A best practice alert (BPA) in the health record was developed and implemented following the collection of baseline data. This alert consisted of a popup window that was triggered when a serum T3 laboratory test was ordered for patients prescribed levothyroxine. The alert required user acknowledgement before the serum T3 laboratory test could be ordered. Results: During the 6-week period prior to launching the BPA, serum T3 tests were ordered a mean of 162.3 ± 15.4 (standard deviation) occurrences per 10,000 patients per week. Over a 15-week period following implementation of the BPA, the frequency of serum T3 orders steadily decreased and resulted in >44% fewer inappropriate tests being ordered. Conclusion: Although national societal guidelines recommend against ordering serum T3 concentrations while monitoring patients with hypothyroidism managed with levothyroxine, these laboratory tests are frequently ordered. Development of a triggered alert in the health record may reduce inappropriate monitoring practices, decrease costs, and improve utilization of limited health-care resources for this common clinical condition. Abbreviations: ATA = American Thyroid Association; BPA = best practice alert; T3 = triiodothyronine; TSH = thyroid-stimulating hormone.

Exposure of adult mice to perfluorobutanesulfonate impacts ovarian functions through hypothyroxinemia leading to down-regulation of Akt-mTOR signaling.

Perfluorobutanesulfonate (PFBS), a short-chain perfluoroalkyl substance, is used in many industrial products. Preliminary evidence suggests that exposure to PFBS may increase the risk of infertility. The aim of this study was to investigate the influence of PFBS on ovarian function. Herein, we show that exposure of adult female mice to PFBS (200mg/kg/day) (PFBS-mice) caused a decrease in the levels of serum total triiodothyronine and thyroxine, which depended on the activation of peroxisome proliferator-activated receptor α (PPARα). The numbers of secondary, early antral and antral follicles were reduced in PFBS-mice with an increase in the atretic follicles, and these changes were recovered by the replacement of L-thyroxinein or the treatment with PPARα antagonist GW6471. PFBS-induced hypothyroxinemia led to a decrease in the levels of Akt, mTOR and p70S6K phosphorylation in ovarian granular cells and cumulus cells, which suppressed the proliferation of these cells and enhanced autophagic death of granular cells and cumulus cells. The levels of serum estradiol and progesterone were reduced in PFBS-mice with a low expression of the steroidogenic genes Star and P450scc in ovarian tissues, which were sensitive to the replacement of L-thyroxinein or the blockade of PPARα. The results indicate that exposure to PFBS (≥200mg/kg/day) through reducing thyroid hormones causes down-regulation of Akt-mTOR signaling in granular cells and cumulus cells, leading to the deficits in the development of follicles and the biosynthesis of ovarian hormones.

About the possible role of the hypocaloric diet in the pathogenesis of hypothyroidism

Many researchers of the thyroid pathology consider that the investigation of the epidemiology of thyroid disease in conjunction with the study of the diet are relevant. The question is if the unbalanced diet may worsen the course of hypothyroidism. The purpose of this study was to establish the relationship between the peculiarities of the diet of patients with hypothyroidism and the functional state of the thyroid gland. Methods and materials. It was observed 400 women of Polish nationality aged 19–28 years living in Biala Podlaska district of the Lublin Voivodeship of Poland which consider themselves healthy. The blood levels of free (FT3) and total (T3) triiodothyronine, free (FT4) and total (T4) thyroxin, thyrotropic hormone (TSH) were determined. With the help of questionnaires and food tables, the approximate average amount of proteins, fats and carbohydrates in the daily ration was determined, as well as the average amount consumed daily with iodine. The prevalence of hypothyroidism among surveyed women was 3.5 % and was not significantly different from the values ​​observed in the European Union. Women with reduced thyroid function consumed with food significantly 3.78 times less iodine, 2.97 times (P &lt; 0.001) less salt and 1.47 times (P &lt; 0.001) less protein compared to women with normal thyroid function. In addition, women with hypothyroidism consumed with food 2.25 times (P &lt; 0.001) more products with properties of strumogens. The development of hypothyroidism in the examined women was combined with a reduced intake of iodine and proteins with food products and an increased use of products with the properties of strumogens.

Slc:Wistar/ST rats develop unilateral thyroid dysgenesis: A novel animal model of thyroid hemiagenesis

Developmental anomalies of the thyroid gland lead to congenital malformations such as thyroglossal duct cysts and thyroid dysgenesis. However, the pathogenesis of thyroid dysgenesis remains unclear due to the lack of suitable animal models. This study demonstrated that Slc:Wistar/ST rats frequently developed unilateral thyroid dysgenesis, including hemiagenesis, characterized by the absence of one lobe. In Wistar/ST rats, each thyroid lobe was frequently different in size, and approximately 27% and 20% of the rats presented with hemihypoplasia and hemiagenesis of the thyroid gland, respectively. Dysgenesis was predominant on the left side in both sexes, without sex differences. At a young age, thyroid hemiagenesis did not alter body weight. In rats of both sexes with thyroid hemiagenesis, plasma total triiodothyronine and total triiodothyronine levels remained unchanged while plasma thyroid-stimulating hormone levels were significantly elevated in young rats. The remaining thyroid lobes increased in weight, but the follicular epithelial cells appeared normal in terms of their height and proliferating activities. On the side of thyroid dysgenesis, the parathyroid glands were normally localized and were situated at the same location as the contralateral glands. The ultimobranchial body remnants were localized at the level of the thyroid gland along with the cranial thyroid artery and vein, forming cell clusters or cystic structures and containing calcitonin-positive C-cells. In conclusion, Wistar/ST rats developed unilateral thyroid dysgenesis and may be novel and useful animal models for thyroid hemiagenesis in humans and for morphogenesis of pharyngeal pouch-derived organs.

Urinary 3-phenoxybenzoic acid levels and the association with thyroid hormones in adults: Korean National Environmental Health Survey 2012–2014

BackgroundOwing to insecticidal activity at low doses with relatively low toxicity in humans, synthetic pyrethroids have been used widely for pest control in agricultural and domestic settings. Pyrethroids are suspected for potential endocrine disruption. However, the thyroid disrupting effects of pyrethroids, particularly in humans, is relatively underexplored. ObjectivesThis study aimed to report 3-phenoxybenzoic acid (3-PBA) concentrations in urine, and assess its association with serum thyroid hormone (TH) levels in a representative adult population of Korea. MethodsData obtained from representative Korean adults recruited in the Korean National Environmental Health Survey (2nd round, 2012–2014) were analyzed. Urinary 3-PBA levels were associated with serum thyroxine (T4), total triiodothyronine (T3), and thyroid-stimulating hormone (TSH) levels among the Korean adult population. ResultsUrinary 3-PBA levels among Korean adults were >3 times higher than those reported in Canada and the United States. Urinary 3-PBA levels showed negative association with serum T4, and this pattern was not changed after stratification by sex. For T3, the association varied by sex and exposure levels. Male demonstrated the same inverse association between urinary 3-PBA and T3, but female did not show such association. Among adults in the lower half of urinary 3-PBA levels, the association with T3 was significant, while that among the remainder was marginal. The association with T4 remained significant on sensitivity analysis, after controlling for other urinary chemicals. ConclusionUrinary 3-PBA levels in the general Korean adult population were found to be generally higher than those of other countries, and were associated with decreased TH levels. Considering the importance of THs, the public health implications of pyrethroid insecticide exposure warrant further studies.

Effects of maternal exposure to BDE209 on neuronal development and transcription of iodothyronine deiodinase in offspring mice

The present study investigated the alterations in nerve function and its potential mechanism of offspring result from the decabromodiphenyl ether (BDE209) orally gavage (0, 1.5, and 225 mg/kg.d body weight) in pregnant and lactating mice. Weight gain and litter size of maternal mice and body weight of offspring were examined. Learning and memory abilities of offspring were tested by the Morris water maze experiment. Thyroid hormones (THs) concentrations in peripheral blood of offspring were detected by the chemiluminescence enzyme immunoassay. Relative mRNA expression of type 1 iodothyronine deiodinase (dio1), type 2 iodothyronine deiodinase (dio2), and type 3 iodothyronine deiodinase (dio3) in the livers and brains of offspring were measured by QRT-PCR (quantitative real-time polymerase chain reaction). Protein expression of dio3 in the livers and brains of offspring was measured by Western blot. All indexes of offspring were tested at postnatal day (PND) 21 and PND 60, respectively. As a result, administration of BDE209 decreased weight gain and litter size of maternal mice, and reduced body weight of offspring mice, prolonged escape latency and declined guardant time of offspring in the Morris water maze experiment. Moreover, BDE209 elevated serum levels of total thyroxine (T4), total triiodothyronine (T3), free T4, and free T3 in offspring. In addition, maternal exposure to BDE209 inhibited dio1, dio2, dio3 mRNA expression in the livers of offspring, while elevated dio1 mRNA expression and reduced dio3 mRNA expression in the brains of offspring. BDE209 also inhibited the protein expression of dio3 in the livers and brains of offspring. These results indicate that BDE209 exposure to pregnant and lactating mice can cause disruption in serum THs of offspring by altering mRNA and protein expression of iodothyronine deiodinases, which might consequently result in neurologic impairment of offspring mice.

Factors associated with thyroid dysfunction in children with newly diagnosed type 1 diabetes mellitus.

This study aimed to investigate the possible factors associated with thyroid dysfunction (TD) in children with type 1 diabetes mellitus (T1DM). Eighty-seven children with T1DM were evaluated in terms of their clinical profile as well as tested for pancreatic and thyroid antibodies. Thyroid function was tested at baseline and 10 days after treatment onset. Thyroid dysfunction was present in 13 (14.9%) patients after correction of acute metabolic disorders. The prevalence of subclinical hypothyroidism (10.3%) was found to be higher than that of clinical hypothyroidism (3.4%) and clinical hyperthyroidism (1.2%). Both pancreatic and thyroid antibody were detected positive in TD patients, which was significantly different from that with euthyroidism (P<0.01, P<0.05). The frequency of TD family history was significantly higher in subjects with TD rather than with euthyroidism (P<0.01). The levels of free and total triiodothyronine, free and total thyroxine were in the hypothyroid range at the time of admission, all of which increased to normal range after 10 days of therapy in 32 DKA children (P=0.02 and P<0.01). There was a significant correlation between pH and free triiodothyronine levels (P<0.05). TD is related to family factors, autoimmunity, and acute metabolic stress in the T1DM and regular thyroid screening should be performed.

Effect of Chandraprabha Batika on Thyroid Hormone Profile in Male Sprague-Dawley Rats

Chandraprabha Batika (CPB) is an Ayurvedic preparation that is used in the rural population for different purposes as traditional medicine. In this study, the effect of CPB on thyroid hormone profile was evaluated after chronic administration of this drug to male Sprague-Dawley rats. The acute pharmacological test of CPB recorded no death or any signs of toxicity even at the highest dose of 4,000 mg/kg body weight. For chronic pharmacological evaluation, the animals were divided into two groups. The first group was given CPB preparation at a dose of 40 mg/kg body weight for 28 days while the second group that served as the control received water for the same period. After 28 days of chronic administration of the CPB preparation, the following effects on the thyroid hormone panel were noted: a statistically insignificant decrease in the serum circulating total thyroxine (tT4) and total triiodothyronine (tT3) levels of the male rats; a decrease in the serum circulating free thyroxine (fT4) level of the male rats, the increase though not significant yet it was prominent; a statistically insignificant increase in the serum circulating free triiodothyronine (fT3) level of the male rats; an increase in the serum circulating thyroid-stimulating hormone level of the male rats, the increase though not significant yet it was prominent.

Occupational exposure to pesticides and thyroid function in Brazilian soybean farmers

IntroductionAgriculture production has been supported especially by the use of pesticides for crop protection and pest control. Although the agricultural production has been increased by pesticides use, these substances also reach non-target organisms and may become a risk to the health of farmers. Several epidemiological studies in human have investigated the association between exposure to pesticides and altered serum levels of thyroid hormones, reporting both positive and negative results. Overall, the impact of pesticides on human thyroid function is still limited. ObjectiveThe aim of this study was to access serum levels of free thyroxin (FT4), total triiodothyronine (TT3), thyroid-stimulating hormone (TSH), and butyrylcholinesterase (BChE) in soybean farmers in southern Brazil. MethodsThe exposed group was composed by 46 rural workers and 27 subjects not exposed to pesticides composed the control group. All subjects had blood samples collected by venipuncture in order to analyze the serum levels of FT4, TT3, TSH and BChE. ResultsThe results showed a significant decreasing in TSH and increasing in TT3 and FT4 in rural workers, compared to control group. BChE levels were lower in exposed group than in control group. The results suggest that farmers are exposed to mixtures of pesticides with endocrine disruptor properties.

Free Thyroxine Determination in the Emergency Department Is a Predictor of Acute Pancreatitis Evolution.

The aim of this study was to determine the prevalence and type of thyroid hormone levels alterations in patients with acute pancreatitis (AP) and analyze if variations are useful AP progression predictors. Three groups of patients were analyzed: AP patients (n = 90), abdominal pain patients (n = 30), and healthy control subjects (n = 40). Usual blood parameters for AP diagnosis and prognosis, thyroid-stimulating hormone (or thyrotropin), FT4 (free thyroxine), FT3 (free triiodothyronine), and TT3 (total triiodothyronine) levels were analyzed. Thyroid hormone level alterations were detected only within the AP group (41% of total cases), being the reduction in T3 levels the most frequently detected deviation (15.6% of FT3 and 8.3% of TT3 cases). Alterations were not influenced by age or sex. Free thyroxine average values were also significantly higher in the AP group, compared with the healthy control group (P = 0.0005), resulting as independent predictors of both severity and mortality. Mortality in this group was 50%, with deceased patients showing FT4 levels above the reference limit. Our results show that FT4 level determination during the initial clinical evaluation of patients admitted to the emergency service with AP can be included as a severity indicator to help determine the differential care of these cases.

Experimental Studies on the Reproduction of the Thin-Lipped Mullet, Liza ramada

Like females of many commercially important fishes, Liza ramada fail to complete ovarian development and do not undergo final maturation (FOM), ovulation or spawning when reared in captivity. The aim of the present work was to investigate the histological and physiological changes during the reproductive cycle of Liza ramada reared in freshwater fish ponds and during induction of spawning in saline water. In the present study, the levels of total thyroxine (T4), triiodothyronine (T3) and cortisol in the plasma of Liza ramada in a complete reproductive cycle were measured in correlation with the seasonal histological changes in gonads. During the reproductive cycle of females, serum triiodothyronine (T3), thyroxine (T4) and cortisol decreased during ovarian early-vitellogenesis and increased during mid-vitellogenesis to reach a peak for both T4 and cortisol. Then, these hormones declined to low levels during late-vitellogenesis. At the prespawning stage, all mentioned hormones re-increased to high levels and finally declined during induction of spawning. There was a decrease in serum levels of thyroid and cortisol hormones coincided with an increase in testicular activity of the fish. T3 and T4 increased duringtestis ripening to reach a peak during spawning, while cortisol reached a peak during ripe stage and decreased to low levels during spawning. In conclusion, the seasonal changes in thyroid hormones and cortisol concomitant with gonadal maturation and spawning of Liza ramada support role for these hormones in reproduction and stress response of this fish.

Low total and free triiodothyronine levels are associated with insulin resistance in non-diabetic individuals

This study examined associations of thyroid hormone levels and insulin resistance (IR) in non-diabetic individuals. Using a cross-sectional design, 2007–2008 data from the National Health and Nutrition Examination Survey (NHANES) were analyzed. NHANES participants ≥20 years of age with complete data of interest were included. The homeostatic model assessment (HOMA) was used to quantify IR, and treated as a continuous variable. Self-reported diabetes or a fasting glucose ≥7 mmol/L were used as criteria to exclude diabetic subjects. Race, liver function, obesity, hypertension, dyslipidemia, smoking, physical activity, vigorous recreational activity, 2-hour glucose, hemoglobin A1C (HbA1C), high-density lipoprotein, triglyceride, vitamin D and C-reactive protein were covariates significantly associated with HOMA-IR. A total of 1,560 non-diabetic subjects were included in the analysis. When adjusted for all factors significant in the univariate analysis (race, liver function, obesity, hypertension, dyslipidemia, smoking, physical activity, vigorous recreational activity, 2-hour glucose, HbA1C, high-density lipoprotein, triglyceride, vitamin D, and CRP) low total triiodothyronine (TT3) and low free T3 (FT3) were significantly associated with decreased HOMA-IR (adjusted coefficient = −0.486, 95% confidence interval [CI]: −0.936, −0.036; adjusted coefficient = −1.151, 95% CI: −1.952, −0.350, respectively). Insulin resistance is associated with low thyroid hormone levels in non-diabetic individuals.

Expression of sodium/iodide transporters and thyroid stimulating hormone receptors in thyroid cancer patients and its correlation with iodine nutrition status and pathology.

To investigate the relationship between the expression of sodium/iodide transporter (NIS) and thyroid stimulating hormone receptor (TSHR) and iodine nutritional status in patients with thyroid carcinoma. 146 cases of thyroid cancer in Shanghai Gongli Hospital, the Second Military Medical University between February and December 2014 were selected as thyroid cancer group, 120 cases of normal thyroid morphology examined by thyroid ultrasound at the same period were selected as normal group. General information and thyroid function of two groups were recorded and analyzed. H&E staining was used to perform histopathological study on both normal group and thyroid cancer group, and immunohistochemistry was used to detect NIS and TSHR protein expression and position. Reverse transcriptase polymerase chain reaction (RT-PCR) was used for quantitative detection of NIS and TSHR mRNA in the two groups, and the relationship between iodine nutrition and NIS and TSHR expression in thyroid cancer patients was studied. The expression of NIS and TSHR in each group was detected by Western blotting, and the difference in NIS and TSHR expression was analyzed by SPSS 17.0 statistical software. The difference of serum total triiodothyronine (TT3), total thyroxine (TT4), and thyroid stimulating hormone (TSH) levels between the normal group and the thyroid cancer group was statistically significant (p < 0.05). H&E staining showed that the histopathology of the thyroid cancer group was significantly different from that of the normal group. Immunohistochemistry showed the positive expression of NIS and TSHR in thyroid cancer group. The expression of NIS and TSHR mRNA and protein in thyroid cancer patients was significantly lower than that in normal group detected by RT-PCR and Western blotting. Analysis of variance showed that the difference of NIS and TSHR expression between the two groups was statistically significant (p < 0.05). These findings indicated that the expression of NIS and TSHR in thyroid cancer is closely related to iodine nutritional status, which has important research value.