Serum Thyroid Hormone Concentrations Research Articles

Iodine nutrition and thyroid diseases in Chengdu, China: an epidemiological study.

To assess the iodine nutritional status and investigate the prevalence of thyroid diseases in a community population in Chengdu, China. Eighty school-age children were randomly selected for measurements of urinary iodine concentration. A total of 1500 residents over the age of 18 who had lived in Chengdu for more than 5 years were selected by stratified cluster sampling. Serum thyroid hormone concentrations and thyroid autoantibodies were measured, and thyroid ultrasonography was performed. The median urine iodine concentration was 184 µg/l in school-age children. The prevalence of clinical hyperthyroidism, subclinical hyperthyroidism, clinical hypothyroidism and subclinical hypothyroidism was 0.97%, 1.95%, 0.90% and 5.55%, respectively. The prevalence of thyroid autoantibodies and thyroid nodules was 15.82% and 16.87%, respectively. The prevalence of clinical hyper- and hypothyroidism was greater in females than in males (P < 0.05). The prevalence of subclinical hyper- and hypothyroidism, thyroid nodules and thyroid autoantibodies increased significantly with age (P < 0.05). The rate of new abnormal TSH was 9.37%, and the average serum Thyroid Stimulating Hormone (TSH) concentrations increased with age. When TSH >0.71 mU/l, the prevalence of positive TPOAb and/or TgAb increased significantly with rising concentrations of TSH (P < 0.05); however, the prevalence of thyroid nodules did not increase with escalating concentrations of TSH (P = 0.09). Subclinical thyroid diseases, especially subclinical hypothyroidism and thyroid nodules, are common in an iodine sufficient area. Females and the elderly might benefit from routine screening for thyroid diseases, followed by appropriate detection and treatment.

Phthalate Exposure in Relation to Maternal Thyroid and Reproductive Hormone Levels during Pregnancy

There is increasing evidence that exposure to phthalates during pregnancy may elevate the risk of adverse reproductive outcomes such as preterm birth. Maternal endocrine disruption across pregnancy may be one pathway mediating some of these relationships. We investigated whether urinary phthalate metabolites were associated with maternal thyroid (thyroid-stimulating hormone [TSH], free thyroxine [FT4], and free triiodothyronine [FT3]) and reproductive (sex hormone-binding globulin [SHBG], progesterone, and estradiol) hormone levels at multiple time points during pregnancy. Preliminary data (n=106) were obtained from an ongoing prospective birth cohort in Northern Puerto Rico. We measured 11 urinary phthalate metabolite concentrations in urine samples collected up to three visits per subject during pregnancy (18±2, 22±2, and 26±2 weeks of gestation; N=293 total samples). We also measured thyroid and reproductive hormone concentrations in serum collected at up to two time points per subject during pregnancy (18±2 and 26±2 weeks of gestation). In adjusted linear mixed models, we observed significant inverse associations between mono-3-carboxypropyl phthalate (MCPP) and FT3 and between mono-ethyl phthalate (MEP) and progesterone. In cross-sectional analyses by study visit, we detected stronger and statistically significant inverse associations in the third visit between FT3 and MCPP as well as mono-carboxyisooctyl phthalate (MCOP), and between FT4 and metabolites of di-(2-ethylhexyl) phthalate (DEHP) compared to the corresponding results for the first visit. Negative effect estimates for MEP and progesterone were similar between study visits. Urinary phthalate metabolites may be associated with altered maternal thyroid and reproductive hormone levels during pregnancy. In particular, the potential thyroid-disrupting effects of phthalates may be more profound during the latter half of gestation.

P.2.g.002 Depression and body image dissatisfaction in burn reconstruction patients in State Burn Centre of Riga

Few controlled studies have been made of the possible mechanisms and physiological consequences of weight gain after cats have been neutered. In this study, six male and six female cats were gonadectomised and compared with five entire male and six entire female cats, before they were neutered and one and three months later. The neutered males gained significantly more weight (mean [SEM] per cent) than the entire males (30.2 [5·2] v 11·8 [2·3]) and the entire females gained 40·0 (7·3) v 16·1 (3·3) per cent, (P<0·05). The castrated males gained more weight as fat than the sexually intact males (22·0 [3·3] v 8·8 [4S] per cent, P<0·05). There was a significant increase (P<0·05) in daily food intake after neutering. Spayed females underwent a significant decrease in fasting metabolic rate (83·7 [5·5] v 67·2 [23] kcal/kg bodyweight0·'75/day P<0·05). Gonadectomy had minimal effects on serum thyroid hormone concentrations, the resting or fasting metabolic rates in males, or on indices of glucose tolerance.

Fasting-induced changes in hepatic thyroid hormone metabolism in male rats are independent of autonomic nervous input to the liver.

During fasting, profound changes in the regulation of the hypothalamus-pituitary-thyroid axis occur in order to save energy and limit catabolism. In this setting, serum T3 and T4 are decreased without an appropriate TSH and TRH response reflecting central down-regulation of the hypothalamus-pituitary-thyroid axis. Hepatic thyroid hormone (TH) metabolism is also affected by fasting, because type 3 deiodinase (D3) is increased, which is mediated by serum leptin concentrations. A recent study showed that fasting-induced changes in liver TH sulfotransferases (Sults) and uridine 5'-diphospho-glucuronosyltransferase (Ugts) depend on a functional melanocortin system in the hypothalamus. However, the pathways connecting the hypothalamus and the liver that induce these changes are currently unknown. In the present study, we investigated in rats whether the fasting-induced changes in hepatic TH metabolism are regulated by the autonomic nervous system. We selectively cut either the sympathetic or the parasympathetic input to the liver. Serum and liver TH concentrations, deiodinase expression, and activity and Sult and Ugt expression were measured in rats that had been fasted for 36 hours or were fed ad libitum. Fasting decreased serum T3 and T4 concentrations, whereas intrahepatic TH concentrations remained unchanged. D3 expression and activity increased, as was the expression of constitutive androstane receptor, Sult1b1, and Ugt1a1, whereas liver D1 was unaffected. Neither sympathetic nor parasympathetic denervation affected the fasting-induced alterations. We conclude that fasting-induced changes in liver TH metabolism are not regulated via the hepatic autonomic input in a major way and more likely reflect a direct effect of humoral factors on the hepatocyte.

Thyrostimulin deficiency does not alter peripheral responses to acute inflammation-induced nonthyroidal illness.

Thyrostimulin, a putative glycoprotein hormone, comprises the subunits GPA2 and GPB5 and activates the TSH receptor (TSHR). The observation that proinflammatory cytokines stimulate GPB5 transcription suggested a role for thyrostimulin in the pathogenesis of nonthyroidal illness syndrome (NTIS). In the present study, we induced acute inflammation by LPS administration to GPB5(-/-) and WT mice to evaluate the role of thyrostimulin in peripheral thyroid hormone metabolism during NTIS. In addition to serum thyroid hormone concentrations, we studied mRNA expression and activity of deiodinase types I, II, and III (D1, D2, and D3) in peripheral T3 target tissues, including liver, muscle, and white and brown adipose tissue (WAT and BAT), of which the latter three express the TSHR. LPS decreased serum free (f)T4 and fT3 indexes to a similar extent in GPB5(-/-) and WT mice. Serum reverse (r)T3 did not change following LPS administration. LPS also induced significant alterations in tissue D1, D2, and D3 mRNA and activity levels, but only the LPS-induced increase in WAT D2 mRNA expression differed between GPB5(-/-) and WT mice. In conclusion, lacking GPB5 during acute illness does not affect the LPS-induced decrease of serum thyroid hormones while resulting in subtle changes in tissue D2 expression that are unlikely to be mediated via the TSHR.

Exposure of embryos to cyclically cold incubation temperatures durably affects energy metabolism and antioxidant pathways in broiler chickens

Cyclically cold incubation temperatures have been suggested as a means to improve resistance of broiler chickens to ascites; however, the underlying mechanisms are not known. Nine hundred eggs obtained from 48 wk Ross broiler breeders were randomly assigned to 2 incubation treatments: control I eggs were incubated at 37.6°C throughout, whereas for cold I eggs the incubation temperature was reduced by 1°C for 6 h daily from 10 to 18 d of incubation. Thereafter, chickens were reared at standard temperatures or under cold exposure that was associated or not with a postnatal cold acclimation at d 5 posthatch. At hatch, hepatic catalase activity and malondialdehyde content were measured. Serum thyroid hormone and triglyceride concentrations, and muscle expression of several genes involved in the regulation of energy metabolism and oxidative stress were also measured at hatch and 5 and 25 d posthatch. Cold incubation induced modifications in antioxidant pathways with higher catalase activity, but lower expression of avian uncoupling protein 3 at hatch. However, long-term enhancement in the expression of avian uncoupling protein 3 was observed, probably caused by an increase in the expression of the transcription factor peroxisome proliferator activated receptor-γ coactivator-1α. These effects were not systematically associated with an increase in serum triiodothyronine concentrations that were observed only in chickens exposed to both cold incubation and later acclimation at 5 d with cold rearing. Our results suggest that these conditions of cyclically cold incubation resulted in the long-term in changes in antioxidant pathways and energy metabolism, which could enhance the health of chickens reared under cold conditions.

Progress in the study of pathogenesis, diagnosis and therapeutics in thyroid hormone insensitivity syndrome

Thyroid hormone insensitivity syndrome is an inherited syndrome characterized by high serum concentrations of thyroid hormone,accompanied by normal or slightly high serum TSH concentration due to the reduced responsiveness of target tissues to thyroid hormone.Thyroid hormone insensitivity syndromes are related to gene mutations of thyroid hormone receptors,thyroid hormone cell transport defect,and thyroid hormone metabolism defect.This article reviews the progress of pathogenesis,diagnosis,and therapeutics of thyroid hormone insensitivity syndrome. Key words: Thyroid hormone insensitivity syndrome; Receptors; Gene mutation

The effect of long-term thyroid-stimulating hormone suppressive therapy on the cognitive function of elderly patients with differentiated thyroid carcinoma.

Several studies have evidenced the association between subclinical hyperthyroidism and cognitive impairment in the elderly. However, the effect of long-term TSH suppressive therapy on the cognitive function in elderly patients with differentiated thyroid carcinoma (DTC) is still unclear. Our aim was to investigate the effect of long-term TSH suppression on the cognitive function of elderly patients with DTC. A cross-sectional case-control study including 50 DTC patients aged 65 years or older (mean age 70.9 ± 5.0 y) who have received a TSH-suppressive therapy for at least 5 years and 90 control subjects matched for age, sex, education period, and depressive mood was conducted. Major Outcome Measure: Comprehensive cognitive domains were compared between the patient and control groups. The association between serum thyroid hormone concentration and cognitive function was investigated. The patient group had higher serum free T4 levels and suppressed TSH levels compared with the control group. Age, sex, education period, the Korean version of the Geriatric Depression Scale scores, and Cumulative Illness Rating Scale scores were not different between the 2 groups. All assessed neuropsychiatric tests were comparable in both groups. In the patient group, those with higher serum free T4 levels performed better on Mini-Mental State Examination and Trail Making Test A. The association between serum free T4 and Trail Making Test A was maintained after adjusting for age, education period, the Korean version of the Geriatric Depression Scale, and Cumulative Illness Rating Scale. In the control group, serum free T4 and TSH levels were not associated with any of the assessed cognitive domains. Our results demonstrated the safety of long-term TSH suppression on the cognitive function in elderly DTC patients. Furthermore, the positive correlations between serum free T4 levels and some cognitive domains suggest the potential beneficial effects of exogenous levothyroxine on the cognitive function of patients who lack endogenous thyroid hormone.

Beyond the fixed setpoint of the hypothalamus-pituitary-thyroid axis.

The hypothalamus-pituitary-thyroid (HPT) axis represents a classical example of an endocrine feedback loop. This review discusses dynamic changes in HPT axis setpoint regulation, identifying their molecular and cellular determinants, and speculates about their functional role. Hypothalamic thyrotropin-releasing hormone neurons were identified as key components of thyroid hormone (TH) setpoint regulation already in the 1980s, and this was followed by the demonstration of a pivotal role for the thyroid hormone receptor beta in negative feedback of TH on the hypothalamic and pituitary level. Gradually, the concept emerged of the HPT axis setpoint as a fixed entity, aiming at a particular TH serum concentration. However, TH serum concentrations appear to be variable and highly responsive to physiological and pathophysiological environmental factors, including the availability or absence of food, inflammation and clock time. During food deprivation and inflammation, TH serum concentrations decrease without a concomitant rise in serum TSH, reflecting a deviation from negative feedback regulation in the HPT axis. Surprisingly, TH action in peripheral organs in these conditions cannot be simply predicted by decreased serum TH concentrations. Instead, diverse environmental stimuli have differential effects on local TH metabolism, e.g. in liver and muscle, occurring quite independently from decreased TH serum concentrations. The net effect of these differential local changes is probably a major determinant of TH action at the tissue level. In sum, hypothalamic HPT axis setpoint regulation as well as TH metabolism at the peripheral organ level is flexible and dynamic, and may adapt the organism in an optimal way to a range of environmental challenges.

Thyroid hormone and retinoid X receptor function and expression during sea lamprey (Petromyzon marinus) metamorphosis

Sea lampreys (Petromyzon marinus) are members of the ancient class Agnatha and undergo a metamorphosis that transforms blind, sedentary, filter-feeding larvae into free-swimming, parasitic juveniles. Thyroid hormones (THs) appear to be important for lamprey metamorphosis, however, serum TH concentrations are elevated in the larval phase, decline rapidly during early metamorphosis and remain low until metamorphosis is complete; these TH fluctuations are contrary to those of other metamorphosing vertebrates. Moreover, thyroid hormone synthesis inhibitors (goitrogens) induce precocious metamorphosis and exogenous TH treatments disrupt natural metamorphosis in P. marinus. Given that THs exert their effects by binding to TH nuclear receptors (TRs) that often act as heterodimers with retinoid X receptors (RXRs), we cloned and characterized these receptors from P. marinus and examined their expression during metamorphosis. Two TRs (PmTR1 and PmTR2) and three RXRs (PmRXRs) were isolated from P. marinus cDNA. Phylogenetic analyses group the PmTRs together on a branch prior to the gnathostome TRα/β split. The three RXRs also group together, but our data indicated that these transcripts are most likely either allelic variants of the same gene locus, or the products of a lamprey-specific duplication event. Importantly, these P. marinus receptors more closely resemble vertebrate as opposed to invertebrate chordate receptors. Functional analysis revealed that PmTR1 and PmTR2 can activate transcription of TH-responsive genes when treated with nanomolar concentrations of TH and they have distinct pharmacological profiles reminiscent of vertebrate TRβ and TRα, respectively. Also similar to other metamorphosing vertebrates, expression patterns of the PmTRs during lamprey metamorphosis suggest that PmTR1 has a dynamic, tissue-specific expression pattern that correlates with tissue morphogenesis and biochemical changes and PmTR2 has a more uniform expression pattern. This TR expression data suggests that THs, either directly or via a metabolite, may function to positively modulate changes at the tissue or organ levels during lamprey metamorphosis. Collectively the results presented herein support the hypothesis that THs have a dual functional role in the lamprey life cycle whereby high levels promote larval feeding, growth and lipogenesis and low levels promote metamorphosis.

Prevalence of feline hyperthyroidism in mature cats in urban population in Warsaw

Abstract The purpose of this study was to assess the prevalence of feline hyperthyroidism in a cat population in Warsaw, considering risk factors. The study was conducted between June 2007 and July 2011. Seven-year-old and older cats were examined. Diagnosis of feline hyperthyroidism was based on the results of clinical examination, data from clinical history, and serum concentrations of thyroid hormones. Hyperthyroidism was diagnosed in 20.14% of 417 cats (95% confidence interval (CI): 16.28%-24.01%). Statistically significant risk factors were age (odds ratio (OR) = 1.17; 95% CI: 1.08-1.27), feeding with a commercial wet feed (OR = 6.74, 95% CI: 2.03-22.37), and an indoor lifestyle (OR = 2.25, 95% CI: 1.04-4.84). There were no effects of breed, gender, castration, or the frequency of deworming on the occurrence of hyperthyroidism. Feline hyperthyroidism in Warsaw is a prevalent disease. This probably results from chronic exposure to dietary and environmental factors.

Association between the serum concentration of triiodothyronine with components of metabolic syndrome, cardiovascular risk, and diet in euthyroid post-menopausal women without and with metabolic syndrome.

PurposeTo determine the association between the serum concentration of triiodothyronine (T3) with components of metabolic syndrome (MetS), cardiovascular risk (CVR), and diet in euthyroid post-menopausal women without and with MetS.MethodsA cross-sectional study was performed in 120 voluntary women of an indigenous population from Tlaxcala-México. Euthyroid status was assessed measuring the serum concentration of thyrotropin (TSH) and thyroid hormones, while that of estradiol was measured to confirm the postmenopausal condition. MetS was diagnosed using the American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement (AHA/NHLBI) criterion. Estimation of CVR was calculated based on the Framingham scale. Diet components were evaluated based on survey applications. Correlations, logistic regression analyses, ANOVA or Kruskall-Wallis, and chi-square tests were used to determine significant differences (P ≤ 0.05) between women without MetS and women with MetS having different serum concentrations of T3.ResultsTriiodothyronine was positively correlated with insulin but negatively correlated with glucose, high-density lipoprotein cholesterol (HDL-C), and CVR. Compared to women without MetS, women with MetS and low-normal T3 concentration showed a high risk for hyperglycemia and moderate/high risk for CVR. In contrast, a high-normal T3 concentration increased the risk to have a big waist circumference, a high concentration of HDL-C, and insulin resistance. Diet analysis showed a high grade of malnutrition in women from all groups. The intake of calories was positively affected by the T3 concentration, albeit it did not affect the extent of malnutrition.ConclusionsIn contrast to concentrations of TSH, total thyroxin (T4), and free T4, the concentration of serum T3 was strongly correlated with cardio-metabolic variables in euthyroid postmenopausal women. In comparison to women without MetS, a high-normal serum concentration of T3 in women with MetS is positively associated with reduced glycaemia and CVR but negatively related to body mass index (BMI), insulin, insulin resistance, and HDL-C. Although the analyzed population had a nutritional deficiency, both calories and iron intake were positively affected by the T3 concentration. Our results suggest the necessity of health programs monitoring T3 in old people in order to treat hyperglycemia, cardio-metabolic components, and the ageing anorexia.

Evaluation of serum thyroid hormones in dogs with systemic inflammatory response syndrome or sepsis

To determine whether dogs with systemic inflammatory response syndrome (SIRS) or sepsis have derangements in serum thyroid hormone concentrations and to evaluate whether such derangements relate to illness severity or outcome. Prospective observational study. Dogs hospitalized with SIRS or sepsis between May and December 2010 were included. Serum thyroid hormone concentrations were measured in all dogs. Data obtained on admission were used to calculate the Acute Patient Physiologic and Laboratory Evaluation (APPLE) scores. University teaching hospital. Twenty-two consecutive client-owned dogs hospitalized with SIRS or sepsis were enrolled; 18 dogs completed the study and 4 dogs were excluded for incomplete data. Forty-nine healthy dogs owned by volunteers were used as controls. None. Decreased total thyroxine (TT4) concentrations were documented in all septic and 7/9 dogs with SIRS. Free T4 concentrations were decreased, but were within the reference interval in 12/18 dogs with SIRS or sepsis compared to control dogs (P < 0.001). Dogs with increased APPLE(fast) scores were less likely to survive (P = 0.017). Dogs with SIRS or sepsis have derangements in measured serum thyroid hormones. No relationships were identified between thyroid hormone concentrations and survival. The APPLE(fast) score was the only variable predictive of poor outcome.

Effect of low thyroid hormone bioavailability on childhood cognitive development: data from the Avon Longitudinal Study of Parents and Children birth cohort

BackgroundHypothyroidism is associated with impaired cognitive development. Whether free thyroxine (T4) concentrations at the lower end of the reference range also have a negative effect is less clear. A common genetic variant, the Thr92Ala substitution in deiodinase-2 can exacerbate low free T4 concentrations by reducing intracellular conversion of free T4 to free tri-iodothyronine. We aimed to see whether low thyroid hormone bioavailability (free T4 in the lowest quartile and the Thr92Ala substitution in deiodinase-2) in childhood adversely affects cognitive development. MethodsThe data from this study come from a retrospective cross-sectional analysis in a population-based birth cohort study, the Avon Longitudinal Study of Parents and Children. Children had thyroid function tested at age 7 years and extensive cognitive assessments at age 8 years. We assessed the odds of having a lower end intelligence quotient (IQ) (<85) if an individual had low thyroid hormone bioavailability. Analyses were adjusted for age, sex, other thyroid hormone variables, and social class. Findings422 (13·5%) of 3127 children had the Thr92Ala substitution, with 116 children (3·71%) having the combination of free T4 in the lowest quartile and the Thr92Ala substitution. We noted a strong association between children with free T4 in the lowest quartile and the Thr92Ala substitution and lower mean IQ (p=0·008, t test). Individuals with free T4 in the lowest quartile and the Thr92Ala substitution were more likely to have a total IQ score below 85 than individuals with free T4 above the lowest quartile without the substitution (odds ratio 3·03, 95% CI 1·38–6·67; p=0·006). There was no association with IQ below 85 in individuals with free T4 in the lowest quartile without the substitution (1·07, 0·82–1·39; p=0·59). When we considered total IQ as a continuous variable, children with free T4 in the lowest quartile and the Thr92Ala substitution had a lower IQ than did those with free T4 above the lowest quartile without the substitution (β=−0·34, −0·64 to −0·04, p=0·03). InterpretationCommon genetic variation in the intracellular thyroid hormone action pathway seems to substantially modify the effect of low serum thyroid hormone concentrations on IQ. This finding suggests that thyroid hormone concentrations alone do not entirely reflect thyroid status and raises the possibility that thyroxine supplementation in at-risk children might improve cognitive outcomes. FundingBupa Research Foundation, British Thyroid Foundation.

TSH Prevents Bone Resorption and with Calcitriol Synergistically Stimulates Bone Formation in Rats with Low Levels of Calciotropic Hormones

Thyroid-stimulating hormone exerts both antiresorptive and anabolic effects on bone remodeling in aged ovariectomized rats and thyroid stimulating hormone-receptor null mice, supported by clinical results demonstrating that low thyroid-stimulating hormone level is associated with increased bone loss. To further explore the effect of thyroid-stimulating hormone on bone metabolism we introduced here a rat model with removed thyroid and parathyroid glands to obtain low serum concentrations of thyroid and parathyroid hormone, calcitonin and 1,25(OH)2D3. Surgery resulted in hypocalcemia, low parathyroid and thyroid hormone, 1,25(OH)2D3, C-telopeptide, and osteocalcin serum level. Intermittent administration of thyroid-stimulating hormone resulted in a further decrease of serum calcium and decreased level of serum C-telopeptide due to the suppression of bone resorption, while in the same animals osteocalcin in serum was higher indicating an increased bone formation rate. A combination of thyroid-stimulating hormone and 1,25(OH)2D3 significantly increased the serum Ca2+, C-telopeptide and serum osteocalcin values. MicroCT analyses of the distal femur and proximal tibia showed that rats treated with 1,25(OH)2D3 alone or in a combination with thyroid-stimulating hormone had an increased trabecular bone volume, and enhanced trabecular bone quality. Biomechanical testing of the trabecular bone showed an increased maximal load for 105% and 235%, respectively, in rats treated with 1,25(OH)2D3 alone, or in a combination with thyroid-stimulating hormone. We suggest that thyroid-stimulating hormone independently of calciotropic hormones suppressed bone resorption and stimulated bone formation, while in combination with 1,25(OH)2D3 acted synergistically on bone formation resulting in an increased bone volume.

In Patients Who Underwent Total Thyroidectomy Some Non-Steroidal Antiinflammatory Drugs Effects on Thyroid Replacement Therapy

Objective: Non-steroid anti-inflammatory drugs can change serum thyroid hormone concentrations by binding to serum proteins. If misunderstood, this situation can give way to inappropriate diagnoses and faulty treatment planning for thyroid diseases in clinical practice. The purpose of our study was to investigate the effects of ketoprofen, lornoxicam, and etofenamate, which are frequently used in clinical practice, on thyroid function tests. Methodology: The study covered 28 rabbits divided into 4 groups. Groups were administered intramuscular injections daily for 10 days. Thyroid hormones concentrations were tested in the blood samples end of day 10. Results: An increase in free thyroxin level in the lornoxicam group was recorded on day 7 in comparison to other groups (p=0.015). There was a statistical decrease regarding thyroid stimulant hormone concentration after day 5 in all three groups (Day 5 p=0.000, day 7 p=0.003, day 10 p=0.00). Conclusion: We believe that previous history of non-steroid anti-inflammatory drug use should be taken into consideration within the scope of patients’ anamneses because non-steroid anti-inflammatory drug use can change the results of thyroid function tests and this change may lead to misevaluations and mistreatment not only for patients with thyroid diseases but also for normal patients.

The calcium–phosphate balance, modulation of thyroid autoimmune processes and other adverse effects connected with thyroid arterial embolization

In search of new treatment options for thyroid diseases, when conventional procedures are ineffective, contraindicated or associated with serious side effects, safety of thyroid arteries embolization in the treatment of particular thyroid diseases was evaluated. The study included eight subjects with retrosternal toxic goiter, six patients affected by Graves’ disease, five cases of retrosternal non-toxic goiter, two subjects with post-amiodarone hyperthyroidism, and one patient with severe thyroid-related orbitopathy, who underwent selective embolization of thyroid arteries. The study assessed and compared calcium–phosphate balance, modulation of thyroid autoimmunity and the presence of different side effects in patients who underwent the procedure. In addition, the serum concentrations of thyroid hormones, anti-thyroid autoantibodies and thyroid volume have been measured. Five of all enrolled subjects (22.7 %) experienced transient, not clinically relevant hypocalcaemia with no need for calcium supplementation. There were no significant changes in serum calcium levels in patients after embolization of both inferior thyroid arteries. The transient side effects associated with the treatment were neck pain and a slight increase in body temperature. Noted high concentration of free thyroid hormones immediately after the procedure was not accompanied by worsening of symptoms or signs of thyrotoxicosis. In patients with Graves’ disease, a significant decrease in thyrotropin receptor antibodies level was observed. Thyroid arterial embolization does not disturb permanently calcium–phosphate balance, modulates positively thyroid autoimmune processes and is associated with no serious post-procedure side effects. Hence, it may be considered as a safe and effective treatment modality for selected thyroid disorders.

A Clinical Review of the Association of Thyroid Stimulating Hormone and Cognitive Impairment

Clinical and subclinical hypothyroidism as well as overt hyperthyroidism in middle-aged and elderly adults are both associated with decreased cognitive functioning as memory, reaction time, and visuospatial organization. Subclinical hyperthyroidism (SH) or low serum concentrations of TSH concentrations have been associated with dementia in previous epidemiological studies, but the association in the elderly has not been established. There is little or no consensus regarding how thyroid function is associated with cognitive performance in the elderly. In this focused review, we have performed an examination between eleven studies from the last five years examining the association between thyroid function and cognitive performance in elderly people, a group who is overrepresented among individuals with minor abnormalities in serum TSH and thyroid hormone concentration. Six of the studies showed a consistent finding of an association between SH with cognitive impairment or dementia. In general, taking into account the largest and most powerfully designed studies, there is a strong body of evidence supporting the association between SH and cognitive impairment. The scarce number of publications on these topics indicates the need of more research especially regarding longitudinal and interventional studies thus hopefully enabling confirmation or rejection of causality between TSH abnormalities and dementia.

Exercise training induced myosin heavy chain isoform alteration in the infarcted heart

The myosin heavy chain isoform MHC-α has 3-fold higher ATPase activity than MHC-β. After myocardial infarction (MI), MHC-α expression is profoundly downregulated and MHC-β expression is reciprocally upregulated. This shift, which is attributed to low thyroid hormone (TH), contributes to myocardial systolic dysfunction. We investigated the effect of post-MI exercise training on MHC isoforms, TH, and cardiac function. MI was surgically induced in 7-week-old rats by ligation of the coronary artery. The survivors were assigned to 3 groups (n = 10/group): Sham (no MI, no exercise), MISed (MI, no exercise), and MIEx (MI, exercise). Treadmill exercise training began 1 week post-MI and lasted for 8 weeks. Echocardiogram measurements were taken on the day prior to initiation of exercise training and at the end of exercise training. Tissue and blood samples were collected at the end of the experiment. MHC isoform gene and protein expression and TH were measured. Our results illustrated that MHC-α gene expression was higher and MHC-β gene expression was lower in the MIEx group than in the MISed group. Resting serum TH concentrations (T3 and T4) were similar between the 2 MI groups. The MIEx group had higher fractional shortening than the MISed group. In conclusion, post-MI exercise training beneficially altered MHC isoforms and improved cardiac function without changing TH.

Relations of Human Breastmilk Choline Content with Maternal Hormonal Status

An adequate supply of choline is important during the perinatal period for normal growth and neuronal development. Breastmilk is the main nutritional source of choline for breastfed infants. Concentrations of free choline and choline compounds in human breastmilk are influenced by maternal circulatory choline status, maternal diet, and genotype. In the present study, we assessed the relationship between milk content of choline compounds and maternal serum hormonal status. In total, 185 breastfeeding women participated in the study. They were enrolled in the first 3 days after giving birth (expressing colostrum, n = 67), Days 6–14 (expressing transitional milk, n = 47), or Days 28–178 (expressing mature milk, n = 71) postpartum. Written informed consents were obtained from all subjects before participating in the study. The study protocol was approved by the Ethical Committee of Uludag University Medical School (Bursa, Turkey). Foremilk samples were collected by hand expression 3 hours after breakfast and prior to the midday feeding, right after collection of blood samples. Choline compounds were extracted from whole milk and assayed as described previously. Serum hormones were measured by using either the Architect 8200 (Abbott, North Chicago, IL) or the Immulite 2000 (Diagnostic Products Corp., a division of Siemens Healthcare, Los Angeles, CA) autoanalyzer. Commercially available assay kits were used to measure serum leptin, resistin (DSL, Webster, TX), and adiponectin (Linco Research, St. Charles, MO). Relationships between concentrations of choline compounds in milk and hormones in serum were determined by Pearson’s correlation analysis. Values of p< 0.05 were considered significant. Concentrations and content of choline compounds in breastmilk varied in a wide range at all lactation stages and among breastfeeding women (Fig. 1). Colostrum free choline concentrations correlated positively with serum prolactin (r=0.688) and adiponectin (r=0.297) and negatively with serum progesterone (r= -0.336), cortisol (r= -0.390), and leptin (r= -0.353). Phosphocholine concentrations in colostrum correlated positively with serum prolactin (r=0.636), adiponectin (r= 0.333), and resistin (r= 0.248) and negatively with serum cortisol (r= -0.467) and leptin (r= -0.264). Colostrum glycerophosphocholine concentrations correlated positively with serum prolactin (r=0.843) and adiponectin (r=0.264) and negatively with serum progesterone (r= -0.339), cortisol (r= -0.459), and leptin (r= -0.279). Phospholipid-bound choline concentration in colostrum showed weak positive association with serum estradiol (r=0.240) and cortisol (r=0.240) and negative association with adiponectin (r= -0.257). Total choline content correlated positively with serum prolactin (r=0.845) and adiponectin (r=0.278) and negatively with serum progesterone (r= -0.299), cortisol (r= -0.462), and leptin (r= -0.337). Transitional milk free choline concentrations correlated positively with serum prolactin (r= 0.474) and negatively with serum cortisol (r= 0.653) concentrations. Phosphocholine concentrations in transitional milk correlated negatively with serum prolactin (r= 0.334), progesterone (r= 0.311), and cortisol (r= 0.653) concentrations. Transitional milk glycerophosphocholine concentrations correlated negatively with serum prolactin (r= 0.369), progesterone (r= 0.336), and cortisol (r= 0.546) concentrations. Total choline contents in transitional milk correlated negatively with serum prolactin (r= 0.315), progesterone (r= 0.350), and cortisol (r= 0.672) concentrations. No significant correlation was found between concentrations of choline compounds in transitional milk and serum concentrations of estradiol, insulin, thyroid hormones, leptin, adiponectin, resistin, or ghrelin. Mature milk free choline concentrations correlated positively with serum prolactin (r= 0.643) and negatively with serum estradiol (r= 0.254) and cortisol (r= 0.565) concentrations. Phosphocholine concentrations in mature milk correlated negatively with maternal serum estradiol (r= 0.443), progesterone (r= 0.269), cortisol (r= 0332), and insulin (r= 0.406) concentrations. Mature milk glycerophosphocholine concentrations correlated negatively with maternal serum estradiol (r= 0.465), progesterone (r= 0.255), cortisol (r= 0.531), and insulin (r= 0.505) concentrations. Mature milk phospholipid-bound choline concentrations showed negative correlation with serum insulin (r = 0.434) and triiodothyronine (r= 0.310) concentrations. Mature milk total choline concentrations correlated negatively with maternal serum estradiol (r= 0.477), progesterone (r= 0.332), cortisol (r = 0.571), and insulin (r= 0.462) concentrations. No significant correlation was found between concentrations of choline compounds in mature milk and maternal serum concentrations of leptin, adiponectin, resistin, or ghrelin. These data confirm and extend the findings in our previous studies that breastmilk contents of important bioactive