Search results for "Thyroid Hormone"

Parathyroid hormone and insulin-resistance in essential hypertension

2000

Resistance to thyroid hormones. Study of an affected kindred diagnosed at neonatal age

1998

Resistance to thyroid hormones (RTH) is a rare condition of reduced activity of thyroid hormones on peripheral tissues and/or reduced suppression of TSH secretion by thyroid hormones. The disease is characterised by high serum levels of T3, T4, fT3 and fT4, and by unexpectedly normal or high TSH levels. The origin of the resistance has been recognised in a thyroid hormone receptor deficit, whose gene (TRβ) has been mapped on chromosome 3p24.3 and several mutations have been identified. The clinical presentation may vary among a large spectrum from hypo-, to eu-, to hyperthyroidism in different patients, even in the same family. The diagnosis of RTH at birth and in the first months of life i…

Metabolic adaptations in neonatal mother-deprived rabbits

2010

[EN] In order to study the metabolic adaptation in response to 48 h transient doe-litter separation (DLS) in young rabbits (5 rabbits/d group) between postnatal 9 and 11 d, plasma concentrations of thyroid hormones T3 and T4, insulin, leptin, glucose, triglycerides (TG), and free fatty acids (FFA) were examined before (6-8 d), during (9-11 d), and after separation (12-16 d). T3 concentrations in newborn control rabbits gradually increased from 0.6 ng/mL at postnatal 6 d to 1.0 ng/mL at postnatal 16 d, whereas those of T4 remained fairly constant (25 ng/mL) up to postnatal 14 d, when T4 gradually declined to 8 ng/mL. T3 values of DLS newborn rabbits did not differ from those of controls at p…

The nuclear receptor PPARγ selectively inhibits Th17 differentiation in a T cell–intrinsic fashion and suppresses CNS autoimmunity

2009

T helper cells secreting interleukin (IL)-17 (Th17 cells) play a crucial role in autoimmune diseases like multiple sclerosis (MS). Th17 differentiation, which is induced by a combination of transforming growth factor (TGF)-beta/IL-6 or IL-21, requires expression of the transcription factor retinoic acid receptor-related orphan receptor gamma t (ROR gamma t). We identify the nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR gamma) as a key negative regulator of human and mouse Th17 differentiation. PPAR gamma activation in CD4(+) T cells selectively suppressed Th17 differentiation, but not differentiation into Th1, Th2, or regulatory T cells. Control of Th17 differentia…

Activated Thyroid Hormone Promotes Differentiation and Chemotherapeutic Sensitization of Colorectal Cancer Stem Cells by Regulating Wnt and BMP4 Sign…

2016

Abstract Thyroid hormone is a pleiotropic factor that controls many cellular processes in multiple cell types such as cancer stem cells (CSC). Thyroid hormone concentrations in the blood are stable, but the action of the deiodinases (D2–D3) provides cell-specific regulation of thyroid hormone activity. Deregulation of deiodinase function and thyroid hormone status has been implicated in tumorigenesis. Therefore, we investigated the role of thyroid hormone metabolism and signaling in colorectal CSCs (CR-CSC), where deiodinases control cell division and chemosensitivity. We found that increased intracellular thyroid hormone concentration through D3 depletion induced cell differentiation and s…

Expression of thyroid hormone receptor isoforms in the hypertrophic heart of spontaneously hypertensive rats

2001

Thyroid hormones (THs) enhance MHC alpha gene- and repress MHC beta gene-transcription in the heart, by interacting with specific nuclear receptors (TRs), that bind to regulatory sequences localized upstream of basal promoter of myosin heavy chain (MHC) genes. The overall effects of THs include an increase in V1- and a decrease in V3-myosin isozyme concentration in the heart. Myosin V1 contains two MHC alpha chains and has a higher ATPase activity than V3 isoform, which contains two beta chains. Previous studies on papillary muscles of spontaneously hypertensive rats (SHRs) showed that heart hypertrophy is accompanied by a shift from alpha to beta MHC accumulation. The present study was aim…

Growth hormone potentiates thyroid hormone effects on post-exercise phosphocreatine recovery in skeletal muscle.

2012

International audience; OBJECTIVE: The aim of the study was to determine the respective impact of thyroxine and growth hormone on in vivo skeletal mitochondrial function assessed via post exercise phosphocreatine recovery. DESIGN: The hind leg muscles of 32 hypophysectomized rats were investigated using (31)P nuclear magnetic resonance spectroscopy at rest and during the recovery period following a non tetanic stimulation of the sciatic nerve. Each rat was supplemented with hydrocortisone and was randomly assigned to one of the 4 groups: the group Hx was maintained in hypopituitarism., the group HxT was treated with 1 μg/100g/day of thyroxine (T4), the group HxG with 0.2 IU/kg/day of recomb…

Toxicological Profile of Ultrapure 2,2´,3,4,4´,5,5´-Heptachlorbiphenyl (PCB 180) in Adult Rats

2014

PCB 180 is a persistent non-dioxin-like polychlorinated biphenyl (NDL-PCB) abundantly present in food and the environment. Risk characterization of NDL-PCBs is confounded by the presence of highly potent dioxin-like impurities. We used ultrapure PCB 180 to characterize its toxicity profile in a 28-day repeat dose toxicity study in young adult rats extended to cover endocrine and behavioral effects. Using a loading dose/maintenance dose regimen, groups of 5 males and 5 females were given total doses of 0, 3, 10, 30, 100, 300, 1000 or 1700 mg PCB 180/kg body weight by gavage. Dose-responses were analyzed using benchmark dose modeling based on dose and adipose tissue PCB concentrations. Body w…

Relationship between PTH and PSA Values in Patients with Pathological Finding of Benign Prostatic Hyperplasia

2012

The functional relationship between parathyroid glands and prostatic gland is commonly very well known. The aim of our study was to investigate the relationship between serum levels of PTH and serum levels of PSA in patients with pathological finding of BPH. According to 261 transrectal ultrasound-guided prostatic biopsies performed from March 2009 to March 2010, 75 patients, responding to our inclusion criteria, were selected. 26 patients (34.6%) ended the study. All patients with high serum levels of PSA (>4 ng/mL), with histological diagnosis of benign prostatic hyperplasia, underwent the assay of serum levels of PTH. We observed high levels of PTH (> 66 pg/mL) in 9 patients (35.2…

Hematopoietic stem cell function in b-thalassemia is impaired and is rescued by targeting the bone marrow niche

2020

Abstract Hematopoietic stem cells (HSCs) are regulated by signals from the bone marrow (BM) niche that tune hematopoiesis at steady state and in hematologic disorders. To understand HSC-niche interactions in altered nonmalignant homeostasis, we selected β-thalassemia, a hemoglobin disorder, as a paradigm. In this severe congenital anemia, alterations secondary to the primary hemoglobin defect have a potential impact on HSC-niche cross talk. We report that HSCs in thalassemic mice (th3) have an impaired function, caused by the interaction with an altered BM niche. The HSC self-renewal defect is rescued after cell transplantation into a normal microenvironment, thus proving the active role of…