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1.
Nutr Res Rev ; 30(1): 50-72, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28112064

RESUMO

The regulation of linear growth by nutritional and inflammatory influences is examined in terms of growth-plate endochondral ossification, in order to better understand stunted growth in children. Linear growth is controlled by complex genetic, physiological, and nutrient-sensitive endocrine/paracrine/autocrine mediated molecular signalling mechanisms, possibly including sleep adequacy through its influence on growth hormone secretion. Inflammation, which accompanies most infections and environmental enteric dysfunction, inhibits endochondral ossification through the action of mediators including proinflammatory cytokines, the activin A-follistatin system, glucocorticoids and fibroblast growth factor 21 (FGF21). In animal models linear growth is particularly sensitive to dietary protein as well as Zn intake, which act through insulin, insulin-like growth factor-1 (IGF-1) and its binding proteins, triiodothyronine, amino acids and Zn2+ to stimulate growth-plate protein and proteoglycan synthesis and cell cycle progression, actions which are blocked by corticosteroids and inflammatory cytokines. Observational human studies indicate stunting to be associated with nutritionally poor, mainly plant-based diets. Intervention studies provide some support for deficiencies of energy, protein, Zn and iodine and for multiple micronutrient deficiencies, at least during pregnancy. Of the animal-source foods, only milk has been specifically and repeatedly shown to exert an important influence on linear growth in both undernourished and well-nourished children. However, inflammation, caused by infections, environmental enteric dysfunction, which may be widespread in the absence of clean water, adequate sanitation and hygiene (WASH), and endogenous inflammation associated with excess adiposity, in each case contributes to stunting, and may explain why nutritional interventions are often unsuccessful. Current interventions to reduce stunting are targeting WASH as well as nutrition.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Transtornos do Crescimento , Infecções , Inflamação/fisiopatologia , Estado Nutricional/fisiologia , Animais , Criança , Desenvolvimento Infantil , Proteínas Alimentares/administração & dosagem , Sistema Endócrino/fisiopatologia , Ingestão de Energia , Feminino , Humanos , Fator de Crescimento Insulin-Like I/fisiologia , Iodo/deficiência , Micronutrientes/deficiência , Osteogênese , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Deficiência de Proteína , Zinco/deficiência
2.
Br J Nutr ; 115(1): 14-23, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26525425

RESUMO

Undernutrition is a stressor with long-term consequences, and the effect of nutritional recovery on cortisol and thyroid hormone status is unknown. To investigate basal thyroid hormones and the cortisol response to a cold pressor test in children recovered from undernutrition, a cross-sectional study was undertaken on children (6-16 years) separated into four groups: control (n 41), stunted (n 31), underweight (n 27) and recovered (n 31). Salivary cortisol was collected over the course of 10 h: upon awakening, before and after an unpleasant and a pleasant stimulus. Cortisol upon awakening was highest in the stunted and lowest in the underweight groups: control=5·05 (95% CI 3·71, 6·89) nmol/l, stunted=6·62 (95% CI 3·97, 11·02) nmol/l, underweight=2·51 (95% CI 1·75, 3·63) nmol/l and recovered=3·46 (95% CI 2·46, 4·90) nmol/l (P=0·005). Girls had higher cortisol concentrations upon awakening compared with boys (P=0·021). The undernourished groups showed an elevated cortisol response both to the unpleasant stimulus and at the last measurement (16.00 hours) compared with that of the recovered group: AUC, control=2·07 (95% CI 1·69, 2·45) nmol/l×30 min, stunted=2·48 (95% CI 1·91, 3·06) nmol/l×30 min, underweight=2·52 (95% CI 2·07, 2·97) nmol/l×30 min, recovered=1·68 (95% CI 1·26, 2·11) nmol/l×30 min (P=0·042); and control=2·03 (95% CI 1·75, 2·39) nmol/l×30 min, stunted=2·51 (95% CI 1·97, 3·19) nmol/l×30 min, underweight=2·61 (95% CI 2·16, 3·16) nmol/l×30 min, recovered=1·70 (95% CI 1·42, 2·03) nmol/l×30 min (P=0·009). Lower free thyroxine (T4) was found in the recovered and stunted groups: control=1·28 (95% CI 1·18, 1·39) pmol/l, stunted=0·98 (95% CI 0·87, 1·10) pmol/l, underweight=1·10 (95% CI 1·01, 1·21) pmol/l and recovered=0·90 (95% CI 0·83, 0·99) pmol/l (P<0·001). Multivariate analysis showed a lower cortisol concentration along 10 h (06.00-16.00 hours) in the recovered compared with the other groups (P=0·017), and similar concentrations between the recovered and control group. In conclusion, the children with recovery in weight and height had a cortisol stress response similar to control but a lower basal free T4. Longitudinal studies are warranted to determine the extent of these endocrine changes after recovery of undernutrition and in adulthood.


Assuntos
Temperatura Baixa , Hidrocortisona/metabolismo , Desnutrição/metabolismo , Estado Nutricional , Estresse Fisiológico , Glândula Tireoide/metabolismo , Tiroxina/sangue , Adolescente , Área Sob a Curva , Criança , Estudos Transversais , Feminino , Transtornos do Crescimento/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário , Masculino , Desnutrição/terapia , Sistema Hipófise-Suprarrenal , Fatores Sexuais , Hormônios Tireóideos/sangue
3.
Br J Nutr ; 116(6): 1125-33, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27469930

RESUMO

Removing dietary phyto-oestrogens in adult male rats causes obesity and diabetes. As whey proteins have been reported to reduce food intake and improve glucose homoeostasis, we investigated whether they could attenuate susceptibility to obesity and diabetes due to phyto-oestrogen deprivation. To this end, thirty male Wistar rats were fed a high-phyto-oestrogen (HP) or a phyto-oestrogen-free (PF) diet for 10 weeks; six rats from each group were killed. The remaining HP animals (six animals) continued receiving the HP diet for 6 weeks. The remaining PF rats (twelve rats) were divided in two groups: one was given the PF diet and the other a variation of the PF diet plus whey protein (PF-W). Body weight, food intake and adipose tissue weights were recorded. Hypothalamic mRNA expressions of orexigenic (neuropeptide Y, agouti-related protein (AgRP)) and anorexigenic (pro-opiomelanocortin (POMC), cocaine-amphetamine-related transcript (CART)) neuropeptides were quantified by real-time PCR. Serum glucose, insulin and total thyroxine (T4), thyroid-stimulating hormone, testosterone and oestradiol were assessed. After 10 weeks of PF diet, increased body weight, adiposity and energy intake, with up-regulation of AgRP and down-regulation of POMC', were observed. Longer treatment exacerbated these results, increased total T4 levels, reduced oestradiol levels and impaired glucose homoeostasis. PF-W reduced energy intake and increased POMC expression; however, body weight and adiposity remained unchanged. PF-W could not prevent the hormonal changes or the high circulating glucose levels induced by phyto-oestrogen deprivation, but reduced fasting insulin. These data demonstrate that, although 6 weeks of whey administration could not prevent obesity in phyto-oestrogen-deprived rats, the reduction in energy intake and circulating insulin could be beneficial with longer treatments.


Assuntos
Ingestão de Energia/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hipotálamo/metabolismo , Obesidade , Proteínas do Soro do Leite/farmacologia , Ração Animal/análise , Animais , Glicemia , Dieta , Suplementos Nutricionais , Masculino , Fitoestrógenos/administração & dosagem , Fitoestrógenos/farmacologia , RNA/genética , RNA/metabolismo , Ratos , Reação em Cadeia da Polimerase em Tempo Real
4.
Br J Nutr ; 114(11): 1829-37, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26411504

RESUMO

The objective of the present study was to assess the impact of providing small-quantity lipid-based nutrient supplements (SQ-LNS) on the I status of young Burkinabe children. In total, thirty-four communities were assigned to intervention (IC) or non-intervention cohorts (NIC). IC children were randomly assigned to receive 20 g lipid-based nutrient supplements (LNS)/d containing 90 µg I with 0 or 10 mg Zn from 9 to 18 months of age, and NIC children received no SQ-LNS. All the children were exposed to iodised salt through the national salt iodization programme. Spot urinary iodine (UI), thyroid-stimulating hormone (TSH) and total thyroxine (T4) in dried blood spots as well as plasma thyroglobulin (Tg) concentrations were assessed at 9 and 18 months of age among 123 IC and fifty-six NIC children. At baseline and at 18 months, UI, TSH and T4 did not differ between cohorts. Tg concentration was higher in the NIC v. IC at baseline, but this difference did not persist at 18 months of age. In both cohorts combined, the geometric mean of UI was 339·2 (95% CI 298·6, 385·2) µg/l, TSH 0·8 (95% CI 0·7, 0·8) mU/l, T4 118 (95 % CI 114, 122) nmol/l and Tg 26·0 (95% CI 24·3, 27·7) µg/l at 18 months of age. None of the children had elevated TSH at 18 months of age. Marginally more children in NIC (8·9%) had low T4 (15 ppm). A reduction of SQ-LNS I content could be considered in settings with similarly successful salt iodisation programmes.


Assuntos
Deficiências Nutricionais/dietoterapia , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição do Lactente , Iodo/uso terapêutico , Estado Nutricional , Saúde da População Rural , Cloreto de Sódio na Dieta/uso terapêutico , Burkina Faso/epidemiologia , Análise por Conglomerados , Estudos de Coortes , Deficiências Nutricionais/sangue , Deficiências Nutricionais/epidemiologia , Deficiências Nutricionais/urina , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais/efeitos adversos , Feminino , Humanos , Lactente , Iodo/administração & dosagem , Iodo/deficiência , Iodo/urina , Masculino , Prevalência , Risco , Tireoglobulina/sangue , Tireotropina/sangue , Tiroxina/sangue , Zinco/administração & dosagem , Zinco/efeitos adversos , Zinco/deficiência , Zinco/uso terapêutico
5.
AACE Clin Case Rep ; 8(4): 150-153, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35959084

RESUMO

Background/Objective: Lyme disease, the most common vector-borne infection in the United States, causes multisystem inflammation. We describe a patient who presented with symptoms of Lyme disease, carditis, and thyroiditis. Case Report: A 53-year-old woman developed fatigue and dyspnea on exertion 1 month after returning from a trip to Delaware. Her electrocardiogram (ECG) showed first-degree atrioventricular (AV) block with a P-R interval up to 392 milliseconds, in the setting of elevated free thyroxine and undetectable thyroid-stimulating hormone levels. Lyme serology was positive. She was hospitalized and started on ceftriaxone. During the second day of hospitalization, AV block worsened to second-degree Mobitz type II but converted back to first-degree AV block after a few hours. Her 24-hour I-123 thyroid uptake and scan revealed markedly diminished I-123 uptake of 1.2%. On day 4, the P-R interval improved, and she was discharged on doxycycline for 3 weeks. P-R interval on ECG and repeated thyroid function tests were normal after finishing antibiotic treatment. Discussion: In our patient, known exposure to the vector, a classic rash on the chest, improvement in the symptoms, and normalization of thyroid function tests after antibiotic therapy support Lyme infection as a cause of carditis and painless, autoimmune thyroiditis. Conclusion: Our case highlights the importance of considering Lyme disease as a cause of painless, autoimmune thyroiditis, especially in patients with concurrent cardiovascular involvement.

6.
AACE Clin Case Rep ; 8(2): 82-84, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35415227

RESUMO

Background: Antithyroid drugs, such as methimazole (MMI), are standard therapies for the medical management of thyrotoxicosis. Agranulocytosis is a rare but lethal adverse effect of antithyroid medications. We have reported 2 cases of MMI-induced agranulocytosis with similar risk factors that likely predisposed them to this adverse reaction. Case Report: Case 1 involved a 71-year-old woman, with a history of Graves disease, who presented with an altered mental status. She was recently discharged on 40 mg of MMI twice daily, and she continued this dose for 2 months. She was readmitted and found to have neutropenic fever in the setting of MMI-induced agranulocytosis. MMI was discontinued, and she was started on filgrastim. Her cell counts gradually improved, and she was subsequently discharged.Case 2 involved a 68-year-old woman, with a history of Graves disease, who presented with severe back pain, nausea, and vomiting. She was recently discharged on 10 mg of MMI twice daily, which was increased to 10 mg 3 times a day. She was readmitted to the hospital because of a septic shock in the setting of pneumonia, colitis, bacteremia, and MMI-induced agranulocytosis. A bone marrow biopsy showed a polyclonal infiltrate with up to 85% plasma cells. Despite treatment with antibiotics, filgrastim, and continuous renal replacement therapy, she ultimately passed away. Discussion: Although these cases had differing outcomes, they shared similar features and risk factors, including older age, female sex, and relatively higher doses of MMI. Conclusion: Close follow up and awareness of risk factors, such as age, female sex, and higher doses of MMI, may decrease the risk of MMI-induced agranulocytosis and fatal outcomes.

7.
JACC Case Rep ; 4(19): 1227-1230, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36406913

RESUMO

A 26-year-old woman presented at 26 weeks of pregnancy with severe mitral regurgitation (MR) and cardiogenic shock in the setting of profound hyperthyroidism. An intra-aortic balloon pump was placed, and surgical intervention was considered. However, with management of thyrotoxicosis and delivery, complete resolution of MR and cardiogenic shock was achieved. (Level of Difficulty: Intermediate.).

8.
Toxicol Rep ; 9: 323-336, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35284242

RESUMO

A ninety-day oral toxicity study of saponified Capsicum annum fruit extract with 50% (w/w) capsanthin (SCFE-50 C) was performed by oral gavage administration to male and female Sprague-Dawley (SD) rats at doses of 0, 500, 1000 and 2000 mg/kg BW/day for a period of ninety consecutive days. To assess the reversal of toxicity, the treatment phase was followed with a twenty-eight-day recovery period. The treatment with SCFE-50 C in both male and female SD rats showed no mortality, and no treatment-related toxicologically significant changes were observed in any groups. No significant differences between treated and control groups were found in feed consumption, body weight gain, individual organ weights, ocular examination, clinical chemistry or blood biochemistry. The necroscopy and histopathology examination did not reveal any clinically significant changes in male and female rats from the 2000 mg/kg BW/day group. According to this study, the no observable adverse effect level (NOAEL) for saponified Capsicum annum fruit extract with 50% (w/w) capsanthin (SCFE-50 C) administered by oral gavage for 90-days is > 2000 mg/kg BW/day in SD rats.

9.
AACE Clin Case Rep ; 7(6): 360-362, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34250225

RESUMO

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 <0.01 mIU/L (normal range [NR], 0.44-5.3 mIU/L), free thyroxine level of 5.34 ng/dL (NR, 0.64-1.42 ng/dL), total triiodothyronine level of 654 ng/dL (NR, 87-178 ng/dL), and thyroid-stimulating immunoglobulin level of 7.18 IU/L (NR, 0.00-0.55 IU/L). Thyroid ultrasound revealed heterogeneous echotexture with increased vascularity. Nasopharyngeal COVID-19 testing was positive. She was treated promptly with propranolol, propylthiouracil, and hydrocortisone with improvement in symptoms, and later switched to methimazole. Her COVID-19 course was uncomplicated, and she left the hospital with minimal respiratory symptoms. CONCLUSION: Thyroid storms are one of the more prevalent endocrine emergencies and are often precipitated by acute events including infections. Patients with thyroid storms may have concomitant SARS-CoV-2 infection that could influence the clinical course and severity of the disease. In patients with symptoms of thyrotoxicosis and respiratory symptoms, clinicians should consider performing a COVID-19 test.

10.
AACE Clin Case Rep ; 7(1): 36-39, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33851017

RESUMO

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.

11.
JACC Case Rep ; 3(12): 1434-1437, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34557687

RESUMO

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.).

12.
AACE Clin Case Rep ; 7(1): 14-16, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33521256

RESUMO

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 (<1.3) thyroid-stimulating immunoglobulin index and 17 (0.00-1.75) IU/L, respectively. Sixteen days before presenting to the ED, she was diagnosed with COVID-19 by polymerase chain reaction test after reporting typical symptoms, including fever. Infectious symptoms resolved within 10 days. She achieved clinical and laboratory improvements with a combination of methimazole and beta blocker therapy. CONCLUSION: This case documents the occurrence of Graves' thyrotoxicosis following mild symptomatic COVID-19. Whether the preceding infection is coincidental or contributed to GD development requires definitive studies. This presentation may align with the theory of a viral link in the development of autoimmune thyroid disease in those with genetic predisposition.

13.
AACE Clin Case Rep ; 7(2): 121-123, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095468

RESUMO

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.

14.
Acta Pharm Sin B ; 10(11): 2183-2197, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33304785

RESUMO

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 αvß3 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.

15.
Curr Res Toxicol ; 1: 124-132, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34345841

RESUMO

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.

16.
Toxicol Rep ; 7: 730-742, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579134

RESUMO

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.

17.
J Clin Transl Endocrinol ; 19: 100218, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32154116

RESUMO

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.

18.
Proc Nutr Soc ; 78(2): 150-160, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30642416

RESUMO

It is well known that severe iodine deficiency during pregnancy may cause impaired brain development in the child, with effects on cognitive and motor function, hearing and speech. Whether mild-to-moderate deficiency also affects neurological development is less well known, but in the past decade a number of observational studies have been conducted to answer this question and these studies are reviewed in this article. The picture is now emerging that even mild-to-moderate iodine deficiency during pregnancy may be associated with subtle impairments in cognition and school performance, although the evidence from randomised controlled trials is still lacking. As global efforts to eradicate iodine deficiency in populations continue, it is more likely that mild-to-moderate, rather than severe, iodine deficiency will be the issue of concern in pregnancy, and therefore further research in regions of mild-to-moderate deficiency is required to strengthen the research base and to inform public-health policy.


Assuntos
Desenvolvimento Infantil , Iodo/deficiência , Complicações na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Encéfalo/crescimento & desenvolvimento , Criança , Cognição , Suplementos Nutricionais , Feminino , Humanos , Iodo/administração & dosagem , Deficiências da Aprendizagem , Gravidez , Glândula Tireoide/embriologia , Hormônios Tireóideos/fisiologia
19.
J Clin Transl Endocrinol ; 11: 11-17, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29725582

RESUMO

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 ±â€¯15.5 pg/ml (reference range 23-139, follicular phase), TSH 1.78 ±â€¯0.86 mU/L (reference range 0.3-4.2) and PRL 409.4 ±â€¯356 mU/L (reference range 70.8-556) (mean ±â€¯SD). Serum estradiol, TSH and PRL averaged 47.2 ±â€¯27 pg/ml, 0.77 ±â€¯0.48 mU/L and 246.4 ±â€¯206.8 mU/L just prior to the buserelin injection, but they peaked at 253.4 ±â€¯113.5 pg/ml (nv 83-495, midcycle), 3.30 ±â€¯1.65 mU/L and 540.3 ±â€¯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.

20.
Toxicol Rep ; 5: 377-382, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854607

RESUMO

Benzo[a]Pyrene (BaP) is a ubiquitous polycyclic aromatic hydrocarbon (PAH) that has been shown to disrupt the metabolism of thyroid hormone. Then, the present investigation aimed to study the effects of BaP on thyroid function in Liza abu. Fish were injected with 2, 10 and 25 mg/kg-bw of BaP. Samples were taken from blood, thyroid and muscle tissues at days 1, 2, 4, 7, and 14. Blood was evaluated for changes in the plasma levels of TSH, T3 and T4. Also, BaP bioaccumulation in the fish muscle was measured. Thyroid tissues were processed for routine histology. BaP concentration in the muscle of treated fish reached a maximum level after 4 days. Exposure of fish to BaP resulted in a significant decrease in T3 and T4 plasma level and increase in TSH concentration up to day 4. Also some pathological alterations were observed in BaP-exposed fish such as hemorrhage and increased number of large follicles with squamous epithelium. In conclusion, according to the results of the present investigation, short term exposure to sublethal concentrations of BaP significantly affected thyroid function in fish. The results revealed BaP ability to alter thyroid function.

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