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Thyrotoxic periodic paralysis is a life-threatening complication of hyperthyroidism characterized by transient episodes of muscle paralysis and hypokalemia, commonly seen in Asian men. We present a rare case of ventricular fibrillation as the initial presentation of thyrotoxic periodic paralysis. (Level of Difficulty: Intermediate.), Central Illustration

Objective Concurrent autoimmune disorders, including autoimmune hepatitis (AIH), with Graves disease have been reported. Glucocorticoids can simultaneously lower thyroid hormone levels and treat AIH. Recurrence of hyperthyroidism is associated with recurrence of hepatitis. We present a case of coexisting AIH and Graves thyrotoxicosis, which improved with prednisone, but the thyrotoxicosis recurred during a prednisone taper while the hepatitis stayed in remission. Methods Evaluation included measurements of liver enzyme levels, thyroid function tests, and thyroid-stimulating antibodies as well as abdominal ultrasound, magnetic resonance imaging, and liver biopsy. Results A 47-year-old woman presented with nausea and jaundice. Workup showed an aspartate aminotransferase level of 1956 (reference, 10-42) U/L and alanine aminotransferase level of 1634 (reference, 14-54) IU/L. The liver biopsy was consistent with AIH. Nine months later, she reported palpitations, heat intolerance, and weight loss and was diagnosed with Graves disease. The patient received prednisone at 60 mg daily, and the liver and thyroid functions normalized after 1 month. Prednisone was tapered to 5 mg daily. Seven months later, she presented with a thyroid-stimulating hormone level of 0.049 (reference, 0.340-5.6) μIU/mL) and free thyroxine level of 3.96 (reference, 0.58-1.64) ng/dL. Liver enzymes remained at normal levels. Prednisone was increased from 5 to 20 mg to treat hyperthyroidism. The patient was referred for thyroidectomy for a diagnosis of Graves disease with thyrotoxicosis. Conclusion This case is an example of coexisting autoimmune diseases, Graves disease and AIH, with different clinical courses. Despite initial resolution with glucocorticoid therapy, Graves disease recurred, while AIH stayed in remission.

Graphical abstract, Highlights • Acrylamide acts as endocrine disruptor for the thyroid gland function. • Acrylamide increases the transcript expression of proteins related to THs synthesis. • Exposure to acrylamide alters the hypothalamus-pituitary-thyroid axis homeostasis. • Acrylamide induces allostatic regulation of the hypothalamus-pituitary-thyroid axis., Some endocrine-disrupting chemicals (EDCs) can affect the endocrine system through covalent interactions with specific sites, leading to deregulation of physiological homeostasis. The acrylamide (AA) present in some fried or baked foods is an example of an electrophile molecule that is able to form adducts with nucleophilic regions of nervous system proteins leading to neurological defects. A positive correlation between increased urinary AA metabolite concentration and reduced levels of thyroid hormones (TH) was described in adolescents and young adults. Thus, this study aimed to evaluate whether AA affects the physiology of the hypothalamus-pituitary-thyroid (HPT) axis and the possible repercussions in peripheral TH-target systems. For this, male Wistar rats were exposed to doses of 2.5 or 5.0 mg AA/Kg/day, based on the LOAEL (Lowest Observed Adverse Effect Level) during prepubertal development. The expression of molecular markers of HPT functionality was investigated in the hypothalamus, pituitary, thyroid, heart and liver, as well as the hormonal and lipid profiles in blood samples. Herein, we showed that AA acts as EDCs for thyroid gland function, increasing the transcript expression of several proteins related to TH synthesis and altering hypothalamus-pituitary-thyroid axis homeostasis, an effect evidenced by the higher levels of THs in the serum. Compensatory mechanisms were observed in TH-target tissues, such as an increase in Dio3 mRNA expression in the liver and a reduction in Mct8 transcript content in the hearts of AA-treated rats. Together, these results pointed out an allostatic regulation of the HPT axis induced by AA and suggest that chronic exposure to it, mainly associated with food consumption, might be related to the higher prevalence of thyroid dysfunctions.

Graphical abstract, Highlights • Hypothyroidism is the most frequent toxic effect of a large variety of chemical compounds. • The polyherbal bioactive fraction exhibited a pro-thyroid effect in hypothyroidic rats. • The polyherbal fraction restored the propylthiouracil-depleted thyroid hormone levels significantly. • The polyherbal fraction may act through multiple mechanisms to exhibit a pro-thyroid effect., Hypothyroidism is the most frequent consequence of the interaction of a large variety of drugs, environmental pollutants and industrial chemicals with the thyroid gland. It is associated with diminished endocrine function which may lead to hyperlipidemia, diabetes, Alzheimer’s disease, weight gain, and other metabolic disorders. The present study evaluates the pro-thyroid activity of a bioactive fraction from a polyherbal teabag in rats with hypothyroidism induced by propylthiouracil. The teabag was formulated to stimulate synthesis and/or release of T4 and affectthe conversion of T4 to T3. Phytoconstituents of the polyherbal teabag are potent antioxidants that may be responsible for the pro-thyroid activity. The tea-extract (1000 mg) was found to contain 1076 μg of gallic acid and 1131 μg of rutin from HPTLC analysis. Rats received propylthiouracil (8 mg/kg) for the first 15days followed by the polyherbal tea-extract (500, 1000 and 1500 mg/kg), the standard drug levothyroxine (0.1 mg/kg), aerobic exercise, and a combination of tea-extract (1000 mg/kg) and aerobic exercise daily along with propylthiouracil for the next 30 days. Finally, rats received their respective treatments alone without propylthiouracil for 15 more days. Lipid profile and levels of glucose, insulin, T3, T4, TSH, cortisol, homocysteine, creatinine, uric acid, malondialdehyde, glucose-6 phosphatase, and endogenous antioxidants were determined. All treatments attenuated significantly the propylthiouracil-elevated TSH, homocysteine, creatinine, uric acid, glucose-6-phosphatase, insulin, and malondialdehyde levels, and restored favorably the propylthiouracil-altered lipid profile, T3, T4, and endogenous antioxidant levels. The polyherbal tea-extract (1000 and 1500 mg/kg) treatment and thecombination treatment of tea-extract (1000 mg/kg) with aerobic exercise displayed significant restoration of the suboptimalthyroid function. This may be due to a favorablemodulation ofthe hypothalamic-pituitary–thyroid and the hypothalamic–pituitary–adrenal axes.

Made available in DSpace on 2022-04-29T08:39:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Background: It is not clear whether previous thyroid diseases influence the course and outcomes of COVID-19. Methods: The study is a part of a multicentric cohort of patients with confirmed COVID-19 diagnosis from 37 hospitals. Matching for age, sex, number of comorbidities, and hospital was performed for the paired analysis. Results: Of 7,762 patients with COVID-19, 526 had previously diagnosed hypothyroidism and 526 were matched controls. The median age was 70 years, and 68.3% were females. The prevalence of comorbidities was similar, except for coronary and chronic kidney diseases that were higher in the hypothyroidism group (p=0.015 and p=0.001). D-dimer levels were lower in patients with hypothyroid (p=0.037). In-hospital management was similar, but hospital length-of-stay (p=0.029) and mechanical ventilation requirement (p=0.006) were lower for patients with hypothyroidism. There was a trend of lower in-hospital mortality in patients with hypothyroidism (22.1% vs 27.0%; p=0.062). Conclusion: Patients with hypothyroidism had a lower requirement of mechanical ventilation and showed a trend of lower in-hospital mortality. Therefore, hypothyroidism does not seem to be associated with a worse prognosis. Undergrad uate Medical Student. Universidade Federal de Minas Gerais. Avenida Professor Alfredo Balena 190 Endocrinology Unit Department of Internal Medicine Faculdade de Medicina da Universidade Federal de Minas Gerais. Avenida Professor Alfredo Balena 190 Professor and Physician. Internal Medicine Department Universidade Federal do Rio Grande do Sul. Coordinator of the Institute for Health Technology Assessment (IATS/CNPq). Rua Ramiro Barcelos, 2359. Prédio 21 | Sala 507 Physician. Hospital Unimed-BH, Av do Contorno, 3097 Hospitais da Rede Mater Dei Internal Medicine Resident. Hospital Risoleta Tolentino Neves. Rua das Gabirobas 01 Physician. Hospital Santa Rosália Hospital João XXIII. Av. Professor Alfredo Balena 400 Physician. Hospital das Clínicas da Faculdade de Medicina de Botucatu Hospital de Clínicas de Porto Alegre, Av. Ramiro Barcellos, 2350 Hospital Mãe de Deus Hospital Santo Antônio Pharmaceutical. Hospital de Clínicas de Porto Alegre, Av. Ramiro Barcellos, 2350 Coordinator of the Research Sector of Grupo Hospitalar Conceição. Professor of the Graduation Program on Evaluation and Production of Technologies for the Brazilian National Health System Hospital Nossa Senhora da Conceição and Hospital Cristo Redentor, Av. Francisco Trein, 326 Hospital SOS Cárdio Professor and Infectious Diseases Physician. Internal Medicine Department University Hospital Universidade Federal de Minas Gerais, Av. Prof Alfredo Balena, 110 Nephrologist. Hospital Universitário Ciências Médicas Hospital Márcio Cunha Hospital Regional do Oeste, Santa Catarina PhD Departamento de Pneumologia Faculdade de Medicina Universidade Católica do Rio Grande do Sul (RGS) Porto Alegre Brasil. Hospital São Lucas PUCRS PhD. Hospital Mãe de Deus Hospital Universitário de Canoas Universidade Federal do Rio Grande do Sul e Instituto de Avaliação de Tecnologia em Saúde (IATS/CNPQ) Undergraduate Medical Student. Universidade Federal dos Vales do Jequitinhonha e Mucuri. R. Cruzeiro 1 Hospital Luxemburgo Hospital Nossa Senhora da Conceição, Av. Francisco Trein, 326 Hospital Bruno Born, Av. Benjamin Constant, 881 Hospital Moinhos de Vento, Rio Grande do Sul Hospital Metropolitano Odilon Behrens Hospital Santa Cruz Hospital Julia Kubitschek. Avenida Professor Alfredo Balena 190 Hospital São Lucas PUCRS Physician. Hospital Eduardo de Menezes. R. Dr. Cristiano Rezende 2213 Physician. Hospital Metropolitano Doutor Célio de Castro. Rua Dona Luiza 311 Hospital São João de Deus Hospital Semper. Alameda Ezequiel Dias 389 Hospital Universitário Canoas, Rio Grande do Sul Hospital Universitário de Santa Maria, Rio Grande do Sul Hospital Tacchini Associate Professor and Statistician Department of Statistics Universidade Federal de Minas Gerais. Av. Presidente Antônio Carlos, 6627, ICEx, sala 4071 Associate Professor and Internal Medicine Physician. Department of Internal Medicine Medical School; and Telehealth Center University Hospital Universidade Federal de Minas Gerais, Avenida Professor Alfredo Balena 190 sala 246 Researcher. Institute for Health Technology Assessment (IATS/ CNPq). Rua Ramiro Barcelos, 2359. Prédio 21 | Sala 507 Physician. Hospital das Clínicas da Faculdade de Medicina de Botucatu

Background: Nephrotic syndrome (NS) is associated with kidney podocyte injury and may occur as part of thyroid autoimmunity such as Graves’ disease. Therefore, the present study was designed to ascertain if and how podocytes respond to and regulate the input of biologically active thyroid hormone (TH), 3,5,3'-triiodothyronine (T3); and also to decipher the pathophysiological role of type 3 deiodinase (D3), a membrane-bound selenoenzyme that inactivates TH, in kidney disease. Methods: To study D3 function in healthy and injured (PAN, puromycin aminonucleoside and LPS, Lipopolysaccharide-mediated) podocytes, immunofluorescence, qPCR and podocyte-specific D3 knockout mouse were used. Surface plasmon resonance (SPR), co-immunoprecipitation and Proximity Ligation Assay (PLA) were used for the interaction studies. Findings: Healthy podocytes expressed D3 as the predominant deiodinase isoform. Upon podocyte injury, levels of DIO3 transcript and D3 protein were dramatically reduced both in vitro and in the LPS mouse model of podocyte damage. D3 was no longer directed to the cell membrane, it accumulated in the Golgi and nucleus instead. Further, depleting D3 from the mouse podocytes resulted in foot process effacement and proteinuria. Treatment of mouse podocytes with T3 phenocopied the absence of D3 and elicited activation of αvβ3 integrin signaling, which led to podocyte injury. We also confirmed presence of an active thyroid stimulating hormone receptor (TSH-R) on mouse podocytes, engagement and activation of which resulted in podocyte injury. Interpretation: The study provided a mechanistic insight into how D3-αvβ3 integrin interaction can minimize T3-dependent integrin activation, illustrating how D3 could act as a renoprotective thyrostat in podocytes. Further, injury caused by binding of TSH-R with TSH-R antibody, as found in patients with Graves’ disease, explained a plausible link between thyroid disorder and NS. Funding: Funding support from American Thyroid Association (ATA) to NJT (ATA-2018-050.R1). Declaration of Interest: Jochen Reiser has patents on novel strategies for kidney therapeutics and stands to gain royalties from their commercialization. He is the co-founder of Walden Biosciences (Cambridge, MA, USA), a biotechnology company in which he has financial interest, including stock. Other authors have nothing to disclose and there are no competing or conflicting interests. Ethical Approval: All animal experiments were carried out according to the NIH’s Guide for the Care and Use of Experimental Animals (National Academies Press, 2011), and approved by the Institutional Animal Care and Use Committee (IACUC) at Rush University (Chicago, Illinois, USA). Human biopsy kidney sections from healthy donors and patients with FSGS, DN and MCD were procured in accordance with guidelines on human research and with approval of the Institutional Review Board of Rush University Medical Center (Chicago, Illinois, USA).

Objective: Graves’ disease is an autoimmune thyroid disease that is thought to develop following environmental exposure in patients with genetic predisposition. Our objective is to present the first report of Graves’ disease onset immediately following recovery from mild coronavirus disease 2019 (COVID-19), a close temporal occurrence that should be studied further. Methods: We describe the clinical course and laboratory features, including thyroid function studies, antibody testing, and polymerase chain reaction testing for severe acute respiratory syndrome coronavirus 2. Results: A 21-year-old woman with prediabetes, obesity, asthma, and gastroesophageal reflux disease presented to the emergency department reporting 3 days of tachycardia, palpitations, anxiety, and shortness of breath. Laboratory investigation revealed a thyroid-stimulating hormone level of 0.01 (0.30-5.00) mcIU/mL with a free thyroxine level of 3.8 (0.6-1.6) ng/dL, prompting endocrinology consultation. On physical examination, she had mild diffuse thyromegaly without tenderness and a history, which included hypothyroidism in her mother. Antibody testing results demonstrated thyroid-stimulating immunoglobulin and thyrotropin receptor antibody levels of 2.6 (

Objective Tyrosine-kinase inhibitors (TKIs) are chemotherapeutic agents associated with increased thyroid-hormone requirements and altered deiodinase activity. We present the first case to link these findings to the TKI ibrutinib. Methods Serial thyroid-stimulating hormone (TSH), free-thyroxine (FT4), free-triiodothyronine (FT3), and reverse-triiodothyronine (rT3) levels were assessed. Results An 80-year-old, 62-kg woman with hypothyroidism secondary to total thyroidectomy for stage I papillary thyroid cancer, on maintenance levothyroxine (LT4) 137 μg daily, presented for follow-up. Compared to one year prior, the patient’s weight had increased by 2 kg and TSH from 2.58 to 27.60 μIU/mL (normal: 0.45-4.50 μIU/mL) while on pantoprazole. Ibrutinib, her other medication, had been started seven months prior for chronic lymphocytic leukemia. Despite sequential confirmation of proper LT4 adherence and self-administration, adjustment of LT4 to 150 μg, and discontinuation of pantoprazole, the patient’s hypothyroid symptoms worsened, and the TSH was 73.90 μIU/mL six months later. LT4 was increased to 175 μg six days a week and 262.5 μg once weekly. Two months later, the TSH was 3.92 μIU/mL (steady-state condition), FT4 2.32 ng/dL (normal: 0.82-1.77 ng/dL), FT3 1.6 pg/mL (normal: 2.0-4.4 pg/mL), and rT3 69.6 ng/dL (normal: 9.2-24.1 ng/dL). Ibrutinib was discontinued the next month due to gastrointestinal side effects and elevated blood pressure. Four months later, LT4 had been reduced to 150 μg, and the FT4 reached 1.92 ng/dL, FT3 2.0 pg/mL, and rT3 26.6 ng/dL. Conclusion This report links ibrutinib to increased thyroid-hormone requirements in a thyroidectomized woman whose decreased T3:T4, T3:rT3, and T4:rT3 ratios suggested type 3 deiodinase induction and type 2 deiodinase inhibition.

Objective: A thyroid storm is a severe exacerbation of thyrotoxicosis that can cause significant morbidity and mortality. The emergence of the novel coronavirus (SARS-CoV-2) that originated in Wuhan, China, has become a worldwide pandemic. We present the first documented case of thyroid storm (as defined by the Burch-Wartofsky criteria) in a patient with COVID-19. Methods: Laboratory and diagnostic studies, including thyroid function tests, thyroid antibody testing, SARS-CoV-2 nasopharyngeal polymerase chain reaction testing, and thyroid ultrasound were performed. Results: A 25-year-old woman presented to the hospital with dry cough, dyspnea, palpitations, weight loss, diarrhea, and anxiety. Physical examination revealed exophthalmos with proptosis and chemosis, tachycardia, diffusely enlarged goiter with bruit, and fine tremor. Laboratory results demonstrated a thyroid-stimulating hormone level of

Introduction and importance Pituitary apoplexy is defined as a sudden onset of neurologic deficit due to infarction or hemorrhage of the pituitary tumor. We report a case of emergency endoscopic surgery for pituitary apoplexy presenting as cerebral infarction due to ICA compression in a limited resources condition. Case presentation A 38-year-old female presented with acute onset of severe headache, decreased level of consciousness, decreased visual acuity bilaterally, aphasia, and right hemiparesis. Computed tomography angiography showed a hyperdense sellar mass with stenosis of the left ICA. The patient underwent emergent endoscopic transsphenoidal surgery for sellar decompression. Clinical discussion The epidermiology, presentation and diagnosis and strategy of treatments as well as their outcomes were discussed. Conclusion Pituitary apoplexy should be taken into consideration in a patient with increasing headache and neuro-ophthalmic symptoms. Pituitary apoplexy presenting as cerebral infarction is rare. The aim of surgery in emergency setting was sellar decompression. Endoscopic transsphenoidal surgery was an effective treatment., Highlights • Pituitary apoplexy should be taken into consideration in a patient with increasing headache and neuro-ophthalmic symptoms. • Pituitary apoplexy presenting as cerebral infarction is rare. • The aim of surgery in emergency setting was sellar decompression. • Endoscopic transsphenoidal surgery was an effective treatment.

Highlights • The effects of air pollution on the placental iodine load are scarcely studied. • PPM2.5 in the third trimester of pregnancy was inversely associated with the placental iodine load. • DLNMs estimated the week-specific associations between PM2.5 and the placental iodine load. • Iodine mediates the effect of gestational PM2.5 exposure on cord blood FT4., Background Adequate intake of iodine is required for the production of thyroid hormones and contributes in pregnant women to a healthy brain development and growth in their offspring. To date, some evidence exists that fine particulate air pollution is linked with the fetal thyroid hormone homeostasis. However, possible effects of air pollutants on the placental iodine storage have not been investigated so far. Objectives We investigated the association between air pollution exposure to particulate matter with a diameter less than 2.5 µm (PM2.5), NO2, and black carbon and the placental iodine load. Methods The current study is part of the ENVIRONAGE birth cohort and included 470 mother-newborn pairs. Iodine concentrations were measured in placental tissue. A high-resolution air pollution model was used to estimate the daily exposure to PM2.5, NO2, and black carbon over the entire pregnancy based on the maternal residential addresses. Distributed lag nonlinear models (DLNMs) were used to estimate gestational week-specific associations between placental iodine concentrations and the air pollutants to understand the impact of specific exposure windows. Results PM2.5 showed a positive association with placental iodine concentration between the 16th and 22nd week of gestation. In contrast, a significant inverse association between PM2.5 and placental iodine concentration was observed in gestational weeks 29–35. The effect estimate, for a 5 µg/m3 increment in PM2.5 concentration, was the strongest at week 32 (β −0.11 µg/kg; 95%CI: −0.18 to −0.03). No associations were observed between placental iodine concentrations and NO2 or black carbon. Assuming causality, we estimated that placental iodine mediated 26% (−0.33 pmol/L; 95%CI: −0.70 to 0.04 pmol/L) of the estimated effect of a 5 µg/m3 increment in PM2.5 exposure on cord blood free thyroxine (FT4) concentrations. Conclusion In utero exposure to particulate matter during the third trimester of pregnancy is linked with a lower placental iodine load. Furthermore, the effect of air pollution on cord blood FT4 levels was partially mediated by the placental iodine load.

The dynamic or flowing tumor cells just as leukemia cells and circulating tumor cells face a microenvironment difference from the solid tumors, and the related targeting nanomedicines are rarely reported. The existence of fluidic shear stress in blood circulation seems not favorable for the binding of ligand modified nanodrugs with their target receptor. Namely, the binding feature is very essential in this case. Herein, we utilized HSPC, PEG-DSPE, cholesterol and two αvβ3 ligands (RGDm7 and DT4) with different binding rates to build dual-targeting nanovesicles, in an effort to achieve a “fast-binding/slow-unbinding” function. It was demonstrated that the dual-targeting nanovesicles actualized efficient cellular uptake and antitumor effect in vitro both for static and dynamic tumor cells. Besides, the potency of the dual-targeting vesicles for flowing tumor cells was better than that for static tumor cells. Then, a tumor metastasis mice model and a leukemia mice model were established to detect the killing ability of the drug-loaded dual-targeting vesicles to dynamic tumor cells in vivo. The therapy efficacy of the dual-targeting system was higher than other controls including single-targeting ones. Generally, it seems possible to strengthen drug-targeting to dynamic tumor cells via the control of ligand–receptor interaction., Graphical abstract A doxorubicin-loaded lipid vesicle targeted to dynamic tumor cells in flowing blood system. RGDm7 and DT4, helped lipid vesicle bind with αvβ3 on the surface of tumor cell in a “fast-binding/slow-unbinding” way. Meanwhile, DT4 led the lipid vesicle to dissolve near nucleus and promoted the cytotoxicity of doxorubicin.Image 1

After encountering two women with serum thyrotropin (TSH) levels greater in periovulatory phase than in other days of the menstrual cycle, we hypothesized that TSH levels could be sensitive to changes in circulating estrogens in women.The objective of this study was to evaluate whether serum TSH increases after an induced acute increase of serum estradiol, and compare serum TSH increase with that of prolactin (PRL) which is a classic estradiol-upregulated pituitary hormone.In this retrospective study, we resorted to stored frozen sera from 55 women who had undergone the GnRH agonist (buserelin)-acute stimulation test of ovarian steroidogenesis. This test, that is preceded by dexamethasone administration to suppress adrenal steroidogenesis, had been performed to show an increased buserelin-stimulated response of 17-hydroxyprogesterone, a response that is frequent in polycystic ovary syndrome. Fifty-five women had enough serum volume at pertinent times (first observation early in the follicular phase and all times of the test) to permit assay of serum estradiol, TSH and PRL.Before dexamethasone administration, estradiol averaged 26.4 ± 15.5 pg/ml (reference range 23–139, follicular phase), TSH 1.78 ± 0.86 mU/L (reference range 0.3–4.2) and PRL 409.4 ± 356 mU/L (reference range 70.8–556) (mean ± SD).Serum estradiol, TSH and PRL averaged 47.2 ± 27 pg/ml, 0.77 ± 0.48 mU/L and 246.4 ± 206.8 mU/L just prior to the buserelin injection, but they peaked at 253.4 ± 113.5 pg/ml (nv 83–495, midcycle), 3.30 ± 1.65 mU/L and 540.3 ± 695.2 mU/L after injection. The responses to buserelin of estradiol, TSH and PRL were of wide magnitude. There was a significant correlation between TSH peak and serum estradiol peak, betweeen AUC0-24 h-TSH and AUC0-24 h-estradiol, or between PRL peak and estradiol peak and AUC0-24 h -PRL and AUC0-24 h-estradiol in only a subgroup of women.Therefore, women with estradiol-dependent increase in serum TSH do exist. Reference bands of serum TSH dependent on the phases of the menstrual cycle should be available. Keywords: Thyrotropin, Prolactin, Menstrual cycle, Estradiol, Polycystic ovary syndrome, Buserelin

Background & Objective: Patients with mild hypothyroidism often are depressed and have impaired quality of life despite serum free-T4 and T3 within reference values. Therefore, we investigated whether their symptoms were dependent on the concentrations of free -T4 and T3 in the circulation and cerebrospinal fluid (CSF). Methods: Twenty-five newly diagnosed, untreated hypothyroid subjects and as many age- and sex-matched healthy controls were investigated. Blood and CSF sampling was performed in the morning after an overnight fast. Quality of life (QoL) was assessed by a Likert scale. In the hypothyroid subjects, the MADRS rating scale was also used to evaluate symptoms of depression. Furthermore, the results obtained by the questionnaires were related to serum and CSF levels of free- T4 and T3 as well as the ratios between them in CSF and in serum. Results: Self-reported health was considerably lower in hypothyroid subjects. MADRS was considerably higher than the normal range for healthy individuals. Low CSF/serum free-T4 ratio was correlated with an increased depressed state according to MADRS (p < 0.01), and in addition, CSF/serum free-T4 ratio correlated positively with the self-reported general health Likert scale (p < 0.05). Concentrations of TSH, or free-T3 in serum or CSF, were not associated with an increased depressed state or self-reported general health. Conclusions: Low CSF/serum ratio of free-T4 was correlated with impaired general health and mood, in contrast to serum measurements not showing any correlations. These findings might partly explain why some patients with hypothyroidism suffer from mental symptoms, despite adequate serum levels of free-T4. However, the findings need to be confirmed in further and larger studies., Funding Agency:Sodra Sjukvardsregionen and Region Hallands forskningsfond

Thyroglobulin (Tg) is a secreted iodoglycoprotein serving as the precursor for triiodothyronine and thyroxine hormones. Many characterized Tg gene mutations produce secretion-defective variants resulting in congenital hypothyroidism. Tg processing and secretion is controlled by extensive interactions with chaperone, trafficking, and degradation factors comprising the secretory proteostasis network. While dependencies on individual proteostasis network components are known, the integration of proteostasis pathways mediating Tg protein quality control and the molecular basis of mutant Tg misprocessing remain poorly understood. We employ a multiplexed quantitative affinity purification–mass spectrometry approach to define the Tg proteostasis interactome and changes between WT and several congenital hypothyroidism variants. Mutant Tg processing is associated with common imbalances in proteostasis engagement including increased chaperoning, oxidative folding, and engagement by targeting factors for endoplasmic reticulum–associated degradation. Furthermore, we reveal mutation-specific changes in engagement with N-glycosylation components, suggesting distinct requirements for 1 Tg variant on dual engagement of both oligosaccharyltransferase complex isoforms for degradation. Modulating dysregulated proteostasis components and pathways may serve as a therapeutic strategy to restore Tg secretion and thyroid hormone biosynthesis., Graphical Abstract, Highlights • Quantitative multiplexed affinity purification—mass spectrometry was used to map the comprehensive thyroglobulin interactome. • Tg interactome consist of a diverse set of protein quality control components. • Mutants share imbalances with folding, disulfide processing, and degradation elements. • N-glycosylation plays a key role in the degradation of mutant thyroglobulin., In Brief Congenital hypothyroidism can result from mutations in the thyroglobulin (Tg) gene impairing protein secretion of the defective Tg variants. The molecular basis of mutant Tg misprocessing has remained poorly understood. Here we map the Tg interactome and quantify mutation specific changes in protein–protein interactions between Tg and protein quality control components. By integrating interactions across protein quality control pathways, we highlight shared imbalances in protein folding, disulfide processing, and degradation, and reveal mutant-specific roles for N-glycosylation in Tg processing.

Recent work has demonstrated the importance of post-transcriptional gene regulation in toxic responses. In the present study, we used two rat models to investigate mRNA translation in the liver following xenobiotic-induced toxicity. By combining polysome profiling with genomic methodologies, we were able to assess global changes in hepatic mRNA translation. Dio3 (iodothyronine deiodinase type III) was identified as a gene that exhibited specific translational repression and had a functional role in a number of relevant canonical pathways. Western blot analysis indicated that this repression led to reduced D3 (the protein expressed by Dio3) levels, enhanced over time and with increased dose. Using Northern blotting techniques and qRT-PCR (quantitative reverse transcription–PCR), we confirmed further that there was no reduction in Dio3 mRNA, suggesting that translational repression of Dio3 is an important determinant of the reduced D3 protein expression following liver damage. Finally, we show that drug-induced hepatotoxicity appears to cause localized disruptions in thyroid hormone levels in the liver and plasma. We suggest that this leads to reduced translation of Dio3 mRNA, which results in decreased D3 production. It may therefore be possible that this is an important mechanism by which the liver can, upon early signs of damage, act rapidly to maintain its own energy equilibrium, thereby avoiding global disruption of the hypothalamic–pituitary–thyroid axis.

Insulin resistance and impaired glucose homoeostasis are important indicators of Type 2 diabetes and are early risk factors of AD (Alzheimer's disease). An essential feature of AD pathology is the presence of BACE1 (β-site amyloid precursor protein-cleaving enzyme 1), which regulates production of toxic amyloid peptides. However, whether BACE1 also plays a role in glucose homoeostasis is presently unknown. We have used transgenic mice to analyse the effects of loss of BACE1 on body weight, and lipid and glucose homoeostasis. BACE1−/− mice are lean, with decreased adiposity, higher energy expenditure, and improved glucose disposal and peripheral insulin sensitivity than wild-type littermates. BACE1−/− mice are also protected from diet-induced obesity. BACE1-deficient skeletal muscle and liver exhibit improved insulin sensitivity. In a skeletal muscle cell line, BACE1 inhibition increased glucose uptake and enhanced insulin sensitivity. The loss of BACE1 is associated with increased levels of UCP1 (uncoupling protein 1) in BAT (brown adipose tissue) and UCP2 and UCP3 mRNA in skeletal muscle, indicative of increased uncoupled respiration and metabolic inefficiency. Thus BACE1 levels may play a critical role in glucose and lipid homoeostasis in conditions of chronic nutrient excess. Therefore strategies that ameliorate BACE1 activity may be important novel approaches for the treatment of diabetes. Abbreviations: Aβ, β-amyloid peptide; AD, Alzheimer's disease; ADDL, Aβ-derived diffusible ligands; AMPK, AMP-activated protein kinase; APP, amyloid precursor protein; BACE1, β-site amyloid precursor protein-cleaving enzyme 1; BAT, brown adipose tissue; DMEM, Dulbecco's modified Eagle's medium; FBS, fetal bovine serum; FFA, free fatty acid; HBS, Hepes-buffered saline; HFD, high-fat diet; IGTT, intraperitoneal glucose tolerance test; ITT, insulin tolerance test; IRS, insulin receptor substrate; OGTT, oral glucose tolerance test; PDK, phosphoinositide-dependent kinase; PKB, protein kinase B; qMR, quantitative magnetic resonance; qRT-PCR, quantitative real-time PCR; RMR, resting metabolic rate; RQ, respiratory quotient; T4, thyroxine; TG, triacylglycerol; UCP, uncoupling protein; WAT, white adipose tissue; WT, wild-type

TTR (transthyretin) amyloidoses are diseases characterized by the aggregation and extracellular deposition of the normally soluble plasma protein TTR. Ex vivo and tissue culture studies suggest that tissue damage precedes TTR fibril deposition, indicating that early events in the amyloidogenic cascade have an impact on disease development. We used a human cardiomyocyte tissue culture model system to define these events. We previously described that the amyloidogenic V122I TTR variant is cytotoxic to human cardiac cells, whereas the naturally occurring, stable and non-amyloidogenic T119M TTR variant is not. We show that most of the V122I TTR interacting with the cells is extracellular and this interaction is mediated by a membrane protein(s). In contrast, most of the non-amyloidogenic T119M TTR associated with the cells is intracellular where it undergoes lysosomal degradation. The TTR internalization process is highly dependent on membrane cholesterol content. Using a fluorescent labelled V122I TTR variant that has the same aggregation and cytotoxic potential as the native V122I TTR, we determined that its association with human cardiomyocytes is saturable with a KD near 650 nM. Only amyloidogenic V122I TTR compete with fluorescent V122I for cell-binding sites. Finally, incubation of the human cardiomyocytes with V122I TTR but not with T119M TTR, generates superoxide species and activates caspase 3/7. In summary, our results show that the interaction of the amyloidogenic V122I TTR is distinct from that of a non-amyloidogenic TTR variant and is characterized by its retention at the cell membrane, where it initiates the cytotoxic cascade., The differential interaction and processing of an aggregation-prone, disease-associated transthyretin variant with human cardiac cells, compared with a non-disease associated transthyretin mutant may explain the basis of the early events of tissue damage in the transthyretin amyloidoses.

Dichlorodiphenyltrichloroethane (DDT) and its metabolites accumulate in adipose tissue through dietary exposure, and have been proposed to contribute to the development of abdominal obesity, insulin resistance and dyslipidemia. Toxicity may also result when DDT and its metabolites are released from adipose tissue into the bloodstream as a result of rapid weight loss. We hypothesized that DDT-exposed rats fed a high fat diet (HFD) followed by 60% calorie restriction would have an adverse metabolic response to rapid weight loss. To test this, we exposed obese Sprague-Dawley (SD) rats to DDT and a HFD over one month followed by 60% calorie restricted diet for two weeks, and examined metabolic parameters throughout the study. During the HFD feeding period, DDT-exposed rats had significantly elevated postprandial non-esterified fatty acids (NEFAs) and decreased body temperature compared with control rats. During calorie restriction, DDT-exposed rats had lowered food efficiency (weight gained/calories consumed), body temperature, and circulating TSH. Our findings suggest that exposure to DDT may impairs metabolic substrate utilization in rats during dynamic periods of weight gain and weight loss.

The molecular requirements for human myelination are incompletely defined, and further study is needed to fully understand the cellular mechanisms involved during development and in demyelinating diseases. We have established a human co-culture model to study myelination. Our earlier observations showed that addition of human γ-carboxylated growth-arrest-specific protein 6 (Gas6) to human oligodendrocyte progenitor cell (OPC) cultures enhanced their survival and maturation. Therefore, we explored the effect of Gas6 in co-cultures of enriched OPCs plated on axons of human fetal dorsal root ganglia explant. Gas6 significantly enhanced the number of myelin basic protein-positive (MBP+) oligodendrocytes with membranous processes parallel with and ensheathing axons relative to co-cultures maintained in defined medium only for 14 days. Gas6 did not increase the overall number of MBP+ oligodendrocytes/culture; however, it significantly increased the length of MBP+ oligodendrocyte processes in contact with and wrapping axons. Multiple oligodendrocytes were in contact with a single axon, and several processes from one oligodendrocyte made contact with one or multiple axons. Electron microscopy supported confocal Z-series microscopy demonstrating axonal ensheathment by MBP+ oligodendrocyte membranous processes in Gas6-treated co-cultures. Contacts between the axonal and oligodendrocyte membranes were evident and multiple wraps of oligodendrocyte membrane around the axon were visible supporting a model system in which to study events in human myelination and aspects of non-compact myelin formation.

The neuronal RNA-binding protein HuD plays a critical role in the post-transcriptional regulation of short-lived mRNAs during the initial establishment and remodelling of neural connections. We have generated transgenic mice overexpressing this protein (HuD-Tg) in adult DGCs (dentate granule cells) and shown that their mossy fibres contain high levels of GAP-43 (growth-associated protein 43) and exhibit distinct morphological and electrophysiological properties. To investigate the basis for these changes and identify other molecular targets of HuD, DGCs from HuD-Tg and control mice were collected by LCM (laser capture microscopy) and RNAs analysed using DNA microarrays. Results show that 216 known mRNAs transcripts and 63 ESTs (expressed sequence tags) are significantly up-regulated in DGCs from these transgenic mice. Analyses of the 3′-UTRs (3′-untranslated regions) of these transcripts revealed an increased number of HuD-binding sites and the presence of several known instability–conferring sequences. Among these, the mRNA for TTR (transthyretin) shows the highest level of up-regulation, as confirmed by qRT–PCR (quantitative reverse transcription–PCR) and ISH (in situ hybridization). GO (gene ontology) analyses of up-regulated transcripts revealed a large overrepresentation of genes associated with neural development and axogenesis. In correlation with these gene expression changes, we found an increased length of the infrapyramidal mossy fibre bundle in HuD-Tg mice. These results support the notion that HuD stabilizes a number of developmentally regulated mRNAs in DGCs, resulting in increased axonal elongation.

Background Inorganic nitrate (NO3-) is a precursor of nitric oxide (NO) in the body and a large number of short-term studies with dietary nitrate supplementation in animals and humans show beneficial effects on cardiovascular health, exercise efficiency, host defense and ischemia reperfusion injury. In contrast, there is a long withstanding concern regarding the putative adverse effects of chronic nitrate exposure related to cancer and adverse hormonal effects. To address these concerns we performed in mice, a physiological and biochemical multi-analysis on the effects of long-term dietary nitrate supplementation. Design 7 week-old C57BL/6 mice were put on a low-nitrate chow and at 20 weeks-old were treated with NaNO3 (1 mmol/L) or NaCl (1 mmol/L, control) in the drinking water. The groups were monitored for weight gain, food and water consumption, blood pressure, glucose metabolism, body composition and oxygen consumption until one group was reduced to eight animals due to death or illness. At that point remaining animals were sacrificed and blood and tissues were analyzed with respect to metabolism, cardiovascular function, inflammation, and oxidative stress. Results Animals were supplemented for 17 months before final sacrifice. Body composition, oxygen consumption, blood pressure, glucose tolerance were measured during the experiment, and vascular reactivity and muscle mitochondrial efficiency measured at the end of the experiment with no differences identified between groups. Nitrate supplementation was associated with improved insulin response, decreased plasma IL-10 and a trend towards improved survival. Conclusions Long term dietary nitrate in mice, at levels similar to the upper intake range in the western society, is not detrimental., Graphical abstract, Highlights • Long term dietary nitrate supplementation for 17 months in mice. • Nitrate treatment in the upper range in the western society diet, has no adverse health effects. • Chronic nitrate intake in mice improves fasting insulin and insulin response. • Cardiovascular and inflammatory parameters were unchanged after long-term dietary nitrate treatment.