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Tatsuya Kunisue - One of the best experts on this subject based on the ideXlab platform.
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determination of free thyroid hormones in animal serum plasma using ultrafiltration in combination with ultra fast liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2018Co-Authors: Rumi Tanoue, Imari Kume, Yasuo Yamamoto, Kohki Takaguchi, Kei Nomiyama, Shinsuke Tanabe, Tatsuya KunisueAbstract:Abstract Thyroid hormones (THs), which mainly consist of 3, 3′, 5-triiodo- l -thyronine (T3) and L-Thyroxine (T4), play a critical role in regulating biological processes such as growth and metabolism in various animal species. Thus, accurate measurement of T3 and T4, especially physiologically active free (protein-unbound) forms, in serum/plasma is needed for the evaluation of TH homeostasis. However, such high-precision determination of free THs is lacking for non-human species. The present study aimed to develop a highly sensitive and reliable liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for the determination of six free THs in serum/plasma, which is applicable to not only humans but also non-human species. Two different physical separation steps, ultrafiltration (UF) and equilibrium dialysis (ED), were examined to obtain the free TH fraction. Several experimental conditions were carefully optimized and validated for UF or ED using the commercially available bovine serum. As a result, UF at 1100 × g and 37 °C for 30 min with a 30 kDa ultrafiltration device (Centrifree YM-30, Millipore) yielded excellent precision (CV:
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Analysis of Thyroid Hormones in Serum of Baikal Seals and Humans by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) and Immunoassay Methods: Application of the LC-MS/MS Method to Wildlife Tissues
2016Co-Authors: Tatsuya Kunisue, Akifumi Eguchi, Hisato Iwata, Kurunthachalam KannanAbstract:Thyroid hormones (THs) are essential for the regulation of growth and development in both humans and wildlife. Until recently, TH concentrations in the tissues of animals have been examined by immunoassay (IA) methods. IA methods are sensitive, but for TH analysis, they are compromised by a lack of adequate specificity. In this study, we determined the concentrations of six THs, L-Thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3), 3,3′,5′-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2), 3,3′-diiodo-l-thyronine (3,3′-T2), and 3-iodo-l-thyronine (3-T1), in the serum of humans (n = 79) and wild Baikal seals (n = 37), by isotope ([13C6]-T4)-dilution liquid chromatography (LC)-tandem mass spectrometry (MS/MS), and compared the TH levels with those measured by an electrochemiluminescent immunoassay (ECLIA) method. T3 and T4 were detected in all serum samples of both humans and Baikal seals, whereas T1, 3,3′-T2, and 3,5-T2 were below the limit of detection (LOD). rT3 was detected in Baikal seal sera at concentrations higher than T3 in 28 seal samples, indicating an anomaly in deiodinase activity in Baikal seals. In humans, regression analyses of TH concentrations, measured by ECLIA and LC-MS/MS methods, showed significant correlations for T4 (r = 0.852) and T3 (r = 0.676; after removal of a serum sample with abnormal T3 levels). In Baikal seals, a low correlation coefficient (r = 0.466) for T4 levels and no correlation for T3 levels (p = 0.093) were found between ECLIA and LC-MS/MS methods. These results suggest that interference by a nonspecific reaction against anti-T3 and anti-T4 antibodies used in the ECLIA can contribute to inaccuracies in TH measurement in Baikal seals. When the relationship between concentrations of THs in sera and dioxin-like toxic equivalents in blubber samples of Baikal seals (n = 19) was examined, a significantly negative correlation was found for serum T4 levels measured by the LC-MS/MS method, but not for those measured by ECLIA. Thus, our results indicate that the LC-MS/MS method is more reliable and accurate for the elucidation of alteration in circulating TH levels in wildlife, as caused by environmental and physiological factors
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analysis of thyroid hormones in serum of baikal seals and humans by liquid chromatography tandem mass spectrometry lc ms ms and immunoassay methods application of the lc ms ms method to wildlife tissues
Environmental Science & Technology, 2011Co-Authors: Tatsuya Kunisue, Akifumi Eguchi, Hisato Iwata, Kurunthachalam KannanAbstract:Thyroid hormones (THs) are essential for the regulation of growth and development in both humans and wildlife. Until recently, TH concentrations in the tissues of animals have been examined by immunoassay (IA) methods. IA methods are sensitive, but for TH analysis, they are compromised by a lack of adequate specificity. In this study, we determined the concentrations of six THs, L-Thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3), 3,3′,5′-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2), 3,3′-diiodo-l-thyronine (3,3′-T2), and 3-iodo-l-thyronine (3-T1), in the serum of humans (n = 79) and wild Baikal seals (n = 37), by isotope ([13C6]-T4)-dilution liquid chromatography (LC)-tandem mass spectrometry (MS/MS), and compared the TH levels with those measured by an electrochemiluminescent immunoassay (ECLIA) method. T3 and T4 were detected in all serum samples of both humans and Baikal seals, whereas T1, 3,3′-T2, and 3,5-T2 were below the limit of detection (LOD). rT3 was detected in Baikal seal sera at ...
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determination of six thyroid hormones in the brain and thyroid gland using isotope dilution liquid chromatography tandem mass spectrometry
Analytical Chemistry, 2011Co-Authors: Tatsuya Kunisue, Jeffrey W Fisher, Kurunthachalam KannanAbstract:Thyroid hormones (THs) play critical roles in the regulation of growth and development, including brain development, in both humans and animals. Until recently, TH levels were assayed with measurements in serum, using immunoassay (IA)-based methods. IA methods are sensitive but are compromised by the lack of adequate specificity. Furthermore, measurements of TH levels in blood do not necessarily reflect the levels and profiles found in critical organs such as the brain. Measurement of TH levels in the brain is critical for studies that assess the effects of environmental contaminants on TH homeostasis. In this study, we developed a selective and sensitive method for the analysis of six THs, L-Thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3), 3,3′,5′-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2), 3,3′-diiodo-l-thyronine (3,3′-T2), and 3-iodo-l-thyronine (3-T1), in the brain and thyroid gland (TG) using isotope ([13C]T4)-dilution liquid chromatography (LC)/tandem mass spectrometry (MS/MS). Prote...
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a method for the analysis of six thyroid hormones in thyroid gland by liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2010Co-Authors: Tatsuya Kunisue, Kurunthachalam Kannan, Jeffrey W Fisher, Babatope FatuyiAbstract:Perchlorate can competitively inhibit iodide uptake by the thyroid gland (TG) via the sodium/iodide symporter, consequently reducing the production of thyroid hormones (THs). Until recently, the effects of perchlorate on TH homeostasis are being examined through measurement of serum levels of TH, by immunoassay (IA)-based methods. IA methods are fast, but for TH analysis, they are compromised by the lack of adequate specificity. Therefore, selective and sensitive methods for the analysis of THs in TG are needed, for assessment of the effects of perchlorate on TH homeostasis. In this study, we developed a method for the analysis of six THs: L-Thyroxine (T(4)), 3,3',5-triiodo-L-thyronine (T(3)), 3,3',5'-triiodo-L-thyronine (rT(3)), 3,5-diiodo-L-thyronine (3,5-T(2)), 3,3'-diiodo-L-thyronine (3,3'-T(2)), and 3-iodo-L-thyronine (3-T(1)) in TG, using liquid chromatography (LC)-tandem mass spectrometry (MS/MS). TGs used in this study were from rats that had been placed on either iodide-deficient diet or iodide-sufficient diet, and that had either been provided with perchlorate in drinking water (10 mg/kg/day) or control water. TGs were extracted by pronase digestion and then analyzed by LC-MS/MS. The instrumental calibration range for each TH ranged from 1 to 200 ng/ml and showed a high linearity (r>0.99). The method quantification limits (LOQs) were determined to be 0.25 ng/mg TG for 3-T(1); 0.33 ng/mg TG for 3,3'- and 3,5-T(2); and 0.52 ng/mg TG for rT(3), T(3), and T(4). Rats were placed on an iodide-deficient or -sufficient diet for 2.5 months, and for the last 2 weeks of that period were provided either perchlorate (10 mg/kg/day) in drinking water or control water. Iodide deficiency and perchlorate administration both reduced TG stores of rT(3), T(3), and T(4). In iodide-deficient rats, perchlorate exacerbated the reduction in levels of THs in TG. With the advances in analytical methodology, the use of LC-MS/MS for measurement of hormone levels in TG will allow more comprehensive evaluations of the hypothalamic-pituitary-thyroid axis.
Kurunthachalam Kannan - One of the best experts on this subject based on the ideXlab platform.
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Analysis of Thyroid Hormones in Serum of Baikal Seals and Humans by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) and Immunoassay Methods: Application of the LC-MS/MS Method to Wildlife Tissues
2016Co-Authors: Tatsuya Kunisue, Akifumi Eguchi, Hisato Iwata, Kurunthachalam KannanAbstract:Thyroid hormones (THs) are essential for the regulation of growth and development in both humans and wildlife. Until recently, TH concentrations in the tissues of animals have been examined by immunoassay (IA) methods. IA methods are sensitive, but for TH analysis, they are compromised by a lack of adequate specificity. In this study, we determined the concentrations of six THs, L-Thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3), 3,3′,5′-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2), 3,3′-diiodo-l-thyronine (3,3′-T2), and 3-iodo-l-thyronine (3-T1), in the serum of humans (n = 79) and wild Baikal seals (n = 37), by isotope ([13C6]-T4)-dilution liquid chromatography (LC)-tandem mass spectrometry (MS/MS), and compared the TH levels with those measured by an electrochemiluminescent immunoassay (ECLIA) method. T3 and T4 were detected in all serum samples of both humans and Baikal seals, whereas T1, 3,3′-T2, and 3,5-T2 were below the limit of detection (LOD). rT3 was detected in Baikal seal sera at concentrations higher than T3 in 28 seal samples, indicating an anomaly in deiodinase activity in Baikal seals. In humans, regression analyses of TH concentrations, measured by ECLIA and LC-MS/MS methods, showed significant correlations for T4 (r = 0.852) and T3 (r = 0.676; after removal of a serum sample with abnormal T3 levels). In Baikal seals, a low correlation coefficient (r = 0.466) for T4 levels and no correlation for T3 levels (p = 0.093) were found between ECLIA and LC-MS/MS methods. These results suggest that interference by a nonspecific reaction against anti-T3 and anti-T4 antibodies used in the ECLIA can contribute to inaccuracies in TH measurement in Baikal seals. When the relationship between concentrations of THs in sera and dioxin-like toxic equivalents in blubber samples of Baikal seals (n = 19) was examined, a significantly negative correlation was found for serum T4 levels measured by the LC-MS/MS method, but not for those measured by ECLIA. Thus, our results indicate that the LC-MS/MS method is more reliable and accurate for the elucidation of alteration in circulating TH levels in wildlife, as caused by environmental and physiological factors
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analysis of thyroid hormones in serum of baikal seals and humans by liquid chromatography tandem mass spectrometry lc ms ms and immunoassay methods application of the lc ms ms method to wildlife tissues
Environmental Science & Technology, 2011Co-Authors: Tatsuya Kunisue, Akifumi Eguchi, Hisato Iwata, Kurunthachalam KannanAbstract:Thyroid hormones (THs) are essential for the regulation of growth and development in both humans and wildlife. Until recently, TH concentrations in the tissues of animals have been examined by immunoassay (IA) methods. IA methods are sensitive, but for TH analysis, they are compromised by a lack of adequate specificity. In this study, we determined the concentrations of six THs, L-Thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3), 3,3′,5′-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2), 3,3′-diiodo-l-thyronine (3,3′-T2), and 3-iodo-l-thyronine (3-T1), in the serum of humans (n = 79) and wild Baikal seals (n = 37), by isotope ([13C6]-T4)-dilution liquid chromatography (LC)-tandem mass spectrometry (MS/MS), and compared the TH levels with those measured by an electrochemiluminescent immunoassay (ECLIA) method. T3 and T4 were detected in all serum samples of both humans and Baikal seals, whereas T1, 3,3′-T2, and 3,5-T2 were below the limit of detection (LOD). rT3 was detected in Baikal seal sera at ...
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determination of six thyroid hormones in the brain and thyroid gland using isotope dilution liquid chromatography tandem mass spectrometry
Analytical Chemistry, 2011Co-Authors: Tatsuya Kunisue, Jeffrey W Fisher, Kurunthachalam KannanAbstract:Thyroid hormones (THs) play critical roles in the regulation of growth and development, including brain development, in both humans and animals. Until recently, TH levels were assayed with measurements in serum, using immunoassay (IA)-based methods. IA methods are sensitive but are compromised by the lack of adequate specificity. Furthermore, measurements of TH levels in blood do not necessarily reflect the levels and profiles found in critical organs such as the brain. Measurement of TH levels in the brain is critical for studies that assess the effects of environmental contaminants on TH homeostasis. In this study, we developed a selective and sensitive method for the analysis of six THs, L-Thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3), 3,3′,5′-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2), 3,3′-diiodo-l-thyronine (3,3′-T2), and 3-iodo-l-thyronine (3-T1), in the brain and thyroid gland (TG) using isotope ([13C]T4)-dilution liquid chromatography (LC)/tandem mass spectrometry (MS/MS). Prote...
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a method for the analysis of six thyroid hormones in thyroid gland by liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2010Co-Authors: Tatsuya Kunisue, Kurunthachalam Kannan, Jeffrey W Fisher, Babatope FatuyiAbstract:Perchlorate can competitively inhibit iodide uptake by the thyroid gland (TG) via the sodium/iodide symporter, consequently reducing the production of thyroid hormones (THs). Until recently, the effects of perchlorate on TH homeostasis are being examined through measurement of serum levels of TH, by immunoassay (IA)-based methods. IA methods are fast, but for TH analysis, they are compromised by the lack of adequate specificity. Therefore, selective and sensitive methods for the analysis of THs in TG are needed, for assessment of the effects of perchlorate on TH homeostasis. In this study, we developed a method for the analysis of six THs: L-Thyroxine (T(4)), 3,3',5-triiodo-L-thyronine (T(3)), 3,3',5'-triiodo-L-thyronine (rT(3)), 3,5-diiodo-L-thyronine (3,5-T(2)), 3,3'-diiodo-L-thyronine (3,3'-T(2)), and 3-iodo-L-thyronine (3-T(1)) in TG, using liquid chromatography (LC)-tandem mass spectrometry (MS/MS). TGs used in this study were from rats that had been placed on either iodide-deficient diet or iodide-sufficient diet, and that had either been provided with perchlorate in drinking water (10 mg/kg/day) or control water. TGs were extracted by pronase digestion and then analyzed by LC-MS/MS. The instrumental calibration range for each TH ranged from 1 to 200 ng/ml and showed a high linearity (r>0.99). The method quantification limits (LOQs) were determined to be 0.25 ng/mg TG for 3-T(1); 0.33 ng/mg TG for 3,3'- and 3,5-T(2); and 0.52 ng/mg TG for rT(3), T(3), and T(4). Rats were placed on an iodide-deficient or -sufficient diet for 2.5 months, and for the last 2 weeks of that period were provided either perchlorate (10 mg/kg/day) in drinking water or control water. Iodide deficiency and perchlorate administration both reduced TG stores of rT(3), T(3), and T(4). In iodide-deficient rats, perchlorate exacerbated the reduction in levels of THs in TG. With the advances in analytical methodology, the use of LC-MS/MS for measurement of hormone levels in TG will allow more comprehensive evaluations of the hypothalamic-pituitary-thyroid axis.
Paul J Davis - One of the best experts on this subject based on the ideXlab platform.
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Bioactivity of Thyroid Hormone Analogs at Cancer Cells
Frontiers Media S.A., 2018Co-Authors: Paul J Davis, Heng Yuan Tang, Aleck Hercbergs, Hung Yun Lin, Kelly A. Keating, Shaker A MousaAbstract:In the context of genomic thyroid hormone actions in normal (noncancer) cells that involve primary interactions with nuclear thyroid hormone receptors (TRs), L-Thyroxine (T4), and 3,3′,5′-triiodo-L-thyronine (reverse T3, rT3) have little bioactivity. In terms of TRs, T4 is a prohormone from which the active nuclear ligand, 3,5,3′-triido-L-thyronine (T3), is generated by deiodination. Deaminated T4 and T3 metabolites have different genomic effects: tetraiodothyroacetic acid (tetrac) is a low grade thyromimetic derivative of T4, whereas triiodothyroacetic acid (triac), the acetic acid metabolite of T3, has substantial thyromimetic activity. In cancer cells, the cell surface receptor for thyroid hormone on integrin αvβ3 mediates non-genomic actions of thyroid hormone analogs. The integrin is expressed in large measure by cancer cells and dividing endothelial cells and has a substantially different panel of responses to thyroid hormone analogs. At αvβ3, T4 is a potent proliferative, anti-apoptotic and pro-angiogenic hormone and is the primary ligand. rT3 may also be proliferative at this site. In contrast, tetrac and triac are antagonists of T4 at αvβ3, but also have anticancer properties at this site that are independent of their effects on the binding of T4
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they live in the land down under thyroid function and basal metabolic rate in the blind mole rat spalax
Endocrine Research, 2014Co-Authors: Aaron Avivi, Keren Cohen, Paul J Davis, Aleck Hercbergs, Martin Ellis, Eviatar Nevo, Nick Sotnichenko, Mark Band, Osnat AshurfabianAbstract:AbstractThe Israeli blind subterranean mole rat (Spalax ehrenbergi superspecies) lives in sealed underground burrows under extreme, hypoxic conditions. The four Israeli Spalax allospecies have adapted to different climates, the cool–humid (Spalax galili, 2 n = 52 chromosomes), semihumid (S. golani, 2 n = 54) north regions, warm–humid (S. carmeli, 2 n = 58) central region and the warm–dry S. judaei, 2 n = 60) southern regions. A dramatic interspecies decline in basal metabolic rate (BMR) from north to south, even after years of captivity, indicates a genetic basis for this BMR trait. We examined the possibility that the genetically-conditioned interspecies BMR difference was expressed via circulating thyroid hormone. An unexpected north to south increase in serum free thyroxine (FT4) and total 3, 5, 3′-triiodo-L-thyronine (T3) (p < 0.02) correlated negatively with previously published BMR measurements. The increases in serum FT4 and T3 were symmetrical, so that the T3:FT4 ratio – interpretable as an index ...
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thyroid hormones as modulators of immune activities at the cellular level
Thyroid, 2011Co-Authors: Paolo De Vito, Sandra Incerpi, Jens Z Pedersen, Faith B Davis, P. Luly, Paul J DavisAbstract:Background: Increasing evidence suggests that thyroid hormones, L-Thyroxine (T4) and 3,3′,5-triiodo-L-thyronine (T3), are modulators of the immune response. In monocytes, macrophages, leukocytes, n...
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membrane receptor for thyroid hormone physiologic and pharmacologic implications
Annual Review of Pharmacology and Toxicology, 2011Co-Authors: Paul J Davis, Faith B Davis, Shaaban A Mousa, Mary K LuidensAbstract:Plasma membrane integrin αvβ3 is a cell surface receptor for thyroid hormone at which nongenomic actions are initiated. L-Thyroxine (T4) and 3,3′,5-triiodo-L-thyronine (T3) promote angiogenesis and tumor cell proliferation via the receptor. Tetraiodothyroacetic acid (tetrac), a deaminated T4 derivative, blocks the nongenomic proliferative and proangiogenic actions of T4 and T3. Acting at the integrin independently of T4 and T3, tetrac and a novel nanoparticulate formulation of tetrac that acts exclusively at the cell surface have oncologically desirable antiproliferative actions on multiple tumor cell survival pathway genes. These agents also block the angiogenic activity of vascular growth factors. Volume and vascular support of xenografts of human pancreatic, kidney, lung, and breast cancers are downregulated by tetrac formulations. The integrin αvβ3 receptor site for thyroid hormone selectively regulates signal transduction pathways and distinguishes between unmodified tetrac and the nanoparticulate fo...
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human platelet aggregation and degranulation is induced in vitro by l thyroxine but not by 3 5 3 triiodo l thyronine or diiodothyropropionic acid ditpa
Clinical and Applied Thrombosis-Hemostasis, 2010Co-Authors: Shaymaa S Mousa, Faith B Davis, Paul J Davis, Shaker A MousaAbstract:The endogenous thyroid hormones L-Thyroxine (T4) and 3,5,3′-triiodo-L-thyronine (T3) induce angiogenesis via an endothelial cell iodothyronine receptor on integrin αVβ3. This receptor also exists on platelets. Diiodothyropropionic acid (DITPA) and GC-1, a noniodinated thyroid hormone analog, also induce angiogenesis. Here we examined the effects of iodothyronines (L-T4 vs L-T3) and analogs DITPA and GC-1 on human platelet function. Subthreshold aggregation of platelets obtained from healthy human donors was induced with collagen. Platelet activation (proaggregation) and adenosine triphosphate (ATP) secretion (degranulation) induced by L-T 4, L-T4-agarose, L-T3, DITPA, or GC-1 were determined simultaneously. Platelet aggregation and ATP secretion induced by a subthreshold level of collagen were enhanced 3-fold by either L-T4 or L-T 4-agarose (0.01 μmol/L) as compared to control, whereas, L-T 3, DITPA, or GC-1 had no effect under the same conditions. The platelet proaggregatory and degranulation effects of ...
Meri De Angelis - One of the best experts on this subject based on the ideXlab platform.
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Determination of 3-iodothyronamine (3-T1AM) in mouse liver using liquid chromatography-tandem mass spectrometry.
Journal of chromatography. B Analytical technologies in the biomedical and life sciences, 2021Co-Authors: Manuel Miller, Sogol Gachkar, Jens Mittag, Sonja C. Schriever, Paul T. Pfluger, Karl-werner Schramm, Meri De AngelisAbstract:Abstract 3-iodothyronamine (3-T1AM) has been suggested as a novel chemical messenger and potent trace amine-associated receptor 1 ligand in the CNS that occurs naturally as endogenous metabolite of the thyroid hormones. Discrepancies and variations in 3-T1AM plasma and tissue concentrations have nonetheless caused controversy regarding the existence and biological role of 3-T1AM. These discussions are at least partially based on potential analytical artefacts caused by differential decay kinetics of 3-T1AM and the widely used deuterated quantification standard D4-T1AM. Here, we report a novel LC-MS/MS method for the quantification of 3-T1AM in biological specimens using stable isotope dilution with 13C6-T1AM, a new internal standard that showed pharmacodynamic properties comparable to endogenous 3-T1AM. The method detection limit (MDL) and method quantification limit (MQL) of 3-T1AM were 0.04 and 0.09 ng/g, respectively. The spike-recoveries of 3-T1AM were between 85.4% and 94.3%, with a coefficient of variation of 3.7–5.8%. The intra-day and inter-day variations of 3-T1AM were 8.45–11.2% and 3.58–5.73%, respectively. Endogenous 3-T1AM liver values in C57BL/6J mice were 2.20 ± 0.49 pmol/g with a detection frequency of 50%. Higher liver 3-T1AM values were found when C57BL/6J mice were treated with N-acetyl-3-iodothyronamine or O-acetyl-3-iodothyronamine. Overall, our new stable isotope dilution LC-MS/MS method improves both the sensitivity and selectivity compared with existing methods. The concomitant possibility to quantify additional thyroid hormones such as thyroxine, 3,5,3’-triiodothyronine, 3,3’,5’-triiodo-L-thyronine, 3,3’-diiodo-L-thyronine, and 3,5-diiodo-L-thyronine further adds to the value of our novel method in exploring the natural occurrence and fate of 3-T1AM in biological tissues and fluids.
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determination of thyroid hormones in mouse tissues by isotope dilution microflow liquid chromatography mass spectrometry method
Journal of Chromatography B, 2016Co-Authors: Meri De Angelis, Florian Giesert, Daniela Vogtweisenhorn, Brian Finan, Christoffer Clemmensen, Timo D Muller, Matthias H Tschop, Karl-werner SchrammAbstract:Thyroid hormones (THs) play a critical role in the regulation of many biological processes such as growth, metabolism and development both in humans and wildlife. In general, TH levels are measured by immunoassay (IA) methods but the specificity of the antibodies used in these assays limits selectivity. In the last decade, several analytical methods using liquid chromatography-mass spectrometry (LC-MS) and tandem mass spectrometry (LC-MS/MS) have been developed to measure THs. These new techniques proved to be more accurate than the IA analysis and they were widely used for the determination of TH level in different human and animal tissues. A large part of LC-MS/MS methods described in literature employed between 200 and 500mg of sample, however this quantity can be considered too high especially when preclinical studies are conducted using mice as test subjects. Thus an analytical method that reduces the amount of tissue is essential. In this study, we developed a procedure for the analysis of six THs; L-Thyroxine (T4), 3,3',5-triiodo-l-thyronine (T3), 3,3',5'-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (rT2), 3,3'-diiodo-l-thyronine (T2), 3-iodo-l-thyronine (T1) using isotope ((13)C6-T4, (13)C6-T3, (13)C6-rT3, (13)C6-T2) dilution liquid chromatography-mass spectrometry. The major difference with previously described methods lies in the utilization of a nano-UPLC (Ultra Performance Liquid Chromatography) system in micro configuration. This approach leads to a reduction compared to the published methods, of column internal diameter, flow rate, and injected volume. The result of all these improvements is a decrease in the amount of sample necessary for the analysis. The method was tested on six different mouse tissues: liver, heart, kidney, muscle, lung and brown adipose tissue (BAT). The nano-UPLC system was interfaced with a quadrupole time-of-flight mass spectrometer (Q-TOF2-MS) using the positive ion mode electrospray ionization. In our analytical method the instrumental calibration curves were constructed from 0 to 100pgμL(-1) and all of them showed good linearity (r(2)>0.99). The limit of quantification was from 2.5 to 5pg injected into the column. The method recoveries calculated using spiked mouse liver and spiked mouse muscle were between 83% and 118% (except T1 and rT2 at high concentration) with a coefficient of variation (CV) of <10% for all derivatives. The new methodology allows us to measure T4 and T3 concentrations in a range from 21 to about 100mg and give a more extensive insight on thyroid hormone concentration in different mouse tissue.
Faith B Davis - One of the best experts on this subject based on the ideXlab platform.
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thyroid hormones as modulators of immune activities at the cellular level
Thyroid, 2011Co-Authors: Paolo De Vito, Sandra Incerpi, Jens Z Pedersen, Faith B Davis, P. Luly, Paul J DavisAbstract:Background: Increasing evidence suggests that thyroid hormones, L-Thyroxine (T4) and 3,3′,5-triiodo-L-thyronine (T3), are modulators of the immune response. In monocytes, macrophages, leukocytes, n...
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membrane receptor for thyroid hormone physiologic and pharmacologic implications
Annual Review of Pharmacology and Toxicology, 2011Co-Authors: Paul J Davis, Faith B Davis, Shaaban A Mousa, Mary K LuidensAbstract:Plasma membrane integrin αvβ3 is a cell surface receptor for thyroid hormone at which nongenomic actions are initiated. L-Thyroxine (T4) and 3,3′,5-triiodo-L-thyronine (T3) promote angiogenesis and tumor cell proliferation via the receptor. Tetraiodothyroacetic acid (tetrac), a deaminated T4 derivative, blocks the nongenomic proliferative and proangiogenic actions of T4 and T3. Acting at the integrin independently of T4 and T3, tetrac and a novel nanoparticulate formulation of tetrac that acts exclusively at the cell surface have oncologically desirable antiproliferative actions on multiple tumor cell survival pathway genes. These agents also block the angiogenic activity of vascular growth factors. Volume and vascular support of xenografts of human pancreatic, kidney, lung, and breast cancers are downregulated by tetrac formulations. The integrin αvβ3 receptor site for thyroid hormone selectively regulates signal transduction pathways and distinguishes between unmodified tetrac and the nanoparticulate fo...
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human platelet aggregation and degranulation is induced in vitro by l thyroxine but not by 3 5 3 triiodo l thyronine or diiodothyropropionic acid ditpa
Clinical and Applied Thrombosis-Hemostasis, 2010Co-Authors: Shaymaa S Mousa, Faith B Davis, Paul J Davis, Shaker A MousaAbstract:The endogenous thyroid hormones L-Thyroxine (T4) and 3,5,3′-triiodo-L-thyronine (T3) induce angiogenesis via an endothelial cell iodothyronine receptor on integrin αVβ3. This receptor also exists on platelets. Diiodothyropropionic acid (DITPA) and GC-1, a noniodinated thyroid hormone analog, also induce angiogenesis. Here we examined the effects of iodothyronines (L-T4 vs L-T3) and analogs DITPA and GC-1 on human platelet function. Subthreshold aggregation of platelets obtained from healthy human donors was induced with collagen. Platelet activation (proaggregation) and adenosine triphosphate (ATP) secretion (degranulation) induced by L-T 4, L-T4-agarose, L-T3, DITPA, or GC-1 were determined simultaneously. Platelet aggregation and ATP secretion induced by a subthreshold level of collagen were enhanced 3-fold by either L-T4 or L-T 4-agarose (0.01 μmol/L) as compared to control, whereas, L-T 3, DITPA, or GC-1 had no effect under the same conditions. The platelet proaggregatory and degranulation effects of ...
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l thyroxine vs 3 5 3 triiodo l thyronine and cell proliferation activation of mitogen activated protein kinase and phosphatidylinositol 3 kinase
American Journal of Physiology-cell Physiology, 2009Co-Authors: Heng Yuan Tang, Mary K Luidens, Sandra Incerpi, Faith B Davis, George L Drusano, Shaker A Mousa, Paul J DavisAbstract:3,5,3′-Triiodo-l-thyronine (T3), but not L-Thyroxine (T4), activated Src kinase and, downstream, phosphatidylinositol 3-kinase (PI3-kinase) by means of an αvβ3 integrin receptor on human glioblasto...
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l thyroxine vs 3 5 3 triiodo l thyronine and cell proliferation activation of mitogen activated protein kinase and phosphatidylinositol 3 kinase
American Journal of Physiology-cell Physiology, 2009Co-Authors: Hung Yun Lin, Mary K Luidens, Sandra Incerpi, Faith B Davis, Heng Yuan Tang, George L Drusano, Shaker A Mousa, Mingzeng Sun, Cassie Lin, Paul J DavisAbstract:3,5,3'-Triiodo-l-thyronine (T(3)), but not L-Thyroxine (T(4)), activated Src kinase and, downstream, phosphatidylinositol 3-kinase (PI3-kinase) by means of an alpha(v)beta(3) integrin receptor on human glioblastoma U-87 MG cells. Although both T(3) and T(4) stimulated extracellular signal-regulated kinase (ERK) 1/2, activated ERK1/2 did not contribute to T(3)-induced Src kinase or PI3-kinase activation, and an inhibitor of PI3-kinase, LY-294002, did not block activation of ERK1/2 by physiological concentrations of T(3) and T(4). Thus the PI3-kinase, Src kinase, and ERK1/2 signaling cascades are parallel pathways in T(3)-treated U-87 MG cells. T(3) and T(4) both caused proliferation of U-87 MG cells; these effects were blocked by the ERK1/2 inhibitor PD-98059 but not by LY-294002. Small-interfering RNA knockdown of PI3-kinase confirmed that PI3-kinase was not involved in the proliferative action of T(3) on U-87 MG cells. PI3-kinase-dependent actions of T(3) in these cells included shuttling of nuclear thyroid hormone receptor-alpha (TRalpha) from cytoplasm to nucleus and accumulation of hypoxia-inducible factor (HIF)-1alpha mRNA; LY-294002 inhibited these actions. Results of studies involving alpha(v)beta(3) receptor antagonists tetraiodothyroacetic acid (tetrac) and Arg-Gly-Asp (RGD) peptide, together with mathematical modeling of the kinetics of displacement of radiolabeled T(3) from the integrin by unlabeled T(3) and by unlabeled T(4), are consistent with the presence of two iodothyronine receptor domains on the integrin. A model proposes that one site binds T(3) exclusively, activates PI3-kinase via Src kinase, and stimulates TRalpha trafficking and HIF-1alpha gene expression. Tetrac and RGD peptide both inhibit T(3) action at this site. The second site binds T(4) and T(3), and, via this receptor, the iodothyronines stimulate ERK1/2-dependent tumor cell proliferation. T(3) action here is inhibited by tetrac alone, but the effect of T(4) is blocked by both tetrac and the RGD peptide.
