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1.
Hormonal regulation of some steps of thyroglobulin synthesis and secretion in bicameral cell culture
S. Desruisseau C. Alquier D. Depetris D. Gruffat O. Chabaud 《Journal of cellular physiology》1994,160(2):336-344
Porcine thyroid cells were cultured for 15 days on porous bottom chambers with or without different mixtures of hormones added to serum-free basal medium. Assays with 10% serum were also performed for comparison with previously published results. The effects of the hormones, particularly insulin, TSH and hydrocortisone, were studied on total RNA content, thyroglobulin mRNA level, the amount of thyroglobulin secreted into the apical medium and on glycosylation. Insulin and TSH similarly increased the total RNA content, and their effects were additive. Thyroglobulin mRNA content was increased twofold by insulin and threefold by TSH. When they were added simultaneously, the maximal level of thyroglobulin mRNA was reached, showing that TSH and insulin effects on thyroglobulin gene expression were additive. Hydrocortisone alone did not modify total RNA or thyroglobulin mRNA content but the hormone amplified total RNA when insulin and TSH were present together. The basal level of thyroglobulin secreted into the apical medium was increased threefold by insulin and fourfold by TSH. The effects of these two hormones added together appeared to be additive. Hydrocortisone had no effect alone or even when combined with insulin or TSH. However, when the three hormones were added together, the hormonal response was amplified. TSH effect and insulin effect on the incorporation of 3H-mannose into thyroglobulin as well as on the anionic residue content of the molecule were additive. © 1994 Wiley-Liss, Inc. 相似文献
2.
R J Germinario A McQuillan M Oliveira S Manuel 《Archives of biochemistry and biophysics》1983,226(2):498-505
Glucocorticoids will enhance the growth of cultured human skin fibroblasts in serum-containing medium. In serum-free cultures hydrocortisone (5 X 10(-6) M) will enhance insulin stimulation of sugar transport and DNA synthesis (as measured by thymidine incorporation into trichloroacetic acid-precipitable material). The optimal concentration for the glucocorticoid effect on DNA synthesis was 5 X 10(-8) M for dexamethasone and 5 X 10(-7) M for hydrocortisone. In dexamethasone-treated cells, concentrations of insulin as low as 250 microU/ml (10 ng/ml) were effective in stimulating DNA synthesis. Further, hydrocortisone and dexamethasone (both at 5 X 10(-6) M) exhibited potentiating effects on insulin-stimulated sugar transport. These effects appeared to be mediated via inhibitory actions on the hexose transport system with the preservation of a functional insulin-receptor interaction resulting in insulin stimulation of deoxy-D-glucose transport at physiological insulin concentrations, 250 microU/ml (10 ng/ml). Hydrocortisone also enhanced specific [125I]insulin binding in these cells. The data indicate that the mechanism(s) of glucocorticoid enhancement of two actions of insulin may be different. 相似文献
3.
4.
Regulation of prostaglandin synthesis by thyrotropin, insulin or insulin-like growth factor-I, and serum in FRTL-5 rat thyroid cells. 总被引:1,自引:0,他引:1
The present report shows that thyrotropin (TSH) regulates all three steps involved in prostaglandin synthesis in FRTL-5 rat thyroid cells, i.e. arachidonic acid release from membrane phospholipids, cyclooxygenase (prostaglandin H synthase) action, and individual prostaglandin formation; however, its action at specific steps may require the presence of, or can be duplicated by, insulin, insulin-like growth factor-I (IGF-I), and/or a serum factor. Thus, TSH releases free arachidonic acid from rat FRTL-5 thyroid cells whose phospholipid fraction is radiolabeled with [3H]arachidonic acid; this action involves a pertussis toxin-sensitive G protein, is not cAMP mediated, and does not require insulin or 5% serum. To quantitate TSH effects on cyclooxygenase activity and on individual prostaglandin formation, a homogenate system and a rapid reversed-phase high pressure liquid chromatography procedure have been developed to measure cyclooxygenase metabolites. TSH increased cyclooxygenase activity in homogenates only if the cells were also exposed to insulin, IGF-I, and/or 5% calf serum; TSH alone had no apparent effect on the activity. Maximal activation, 4-fold over basal/micrograms of DNA, took 36 h to achieve and reflected, at least in part, an increase in cyclooxygenase gene expression. Like cyclooxygenase activity, induction of prostaglandin E2 production required 2 or more factors, i.e. TSH plus insulin/IGF-I or TSH plus insulin/IGF-I plus serum. Increased production of prostaglandin D2, could, however, be detected if cells were treated with TSH alone and the TSH activity could be duplicated by insulin, IGF-I, or calf serum alone. 相似文献
5.
Growth and differentiation in cultured human thyroid cells: Effects of epidermal growth factor and thyrotropin 总被引:2,自引:0,他引:2
Janice E. Errick Katherine W. A. Ing Margaret C. Eggo Gerard N. Burrow 《In vitro cellular & developmental biology. Plant》1986,22(1):28-36
Summary Human thyroid cells were grown and subcultured in vitro to examine their responses to known hormones and growth factors, and
to serum. The cells were obtained from surgical specimens and were either neoplastic or nonneoplastic. The effects of culture
conditions on cell growth were measured by changes in cell numbers and by stimulation of [3H]thymidine incorporation. The results showed that serum (0.5%) was essential for cell proliferation, and that a mixture of
insulin (10 μg/ml), transferrin (5 μg/ml), hydrocortisone (10 μg/ml), somatostatin (10 ng/ml), and glycyl-histidyl-lysine
(10 ng/ml) enhanced the effect of serum. Maximum growth of the cells was obtained when epidermal growth factor was present
at 10−9
M. Differentiation was measured by production of thyroglobulin, which was found to be stimulated by thyrotropin. This system
provides a means to study the hormonal control of growth and differentiation in human thyroid cells.
This work was supported by grants from the Medical Research Council of Canada; the Department of Medicine, University of Toronto;
and the National Cancer Institute of Canada. J. E. E. is a C.H. Best Foundation and Department of Medicine postdoctoral fellow. 相似文献
6.
In previous work we demonstrated that circulating thyroglobulin contains very little or no iodine. We have now characterized circulating thyroglobulin following administration of thyrotropin (TSH) to determine whether its iodine content remains low or increases after stimulation. The iodine content of circulating thyroglobulin was estimated from its density determined by equilibrium density gradient (isopycnic) centrifugation. TSH stimulated thyroglobulin from 182 +/- 28 ng/ml to 571 +/- 83 ng/ml at 8-14 h. Circulating thyroglobulin in the basal state had a density consistent with very little or no iodine. Its density increased following TSH to a maximum at 8-14 h which was nearly the same as the density of thyroglobulin extracted directly from the thyroid. To determine whether selective peripheral metabolism, based on the degree of iodination, could account for the density shift, purified rat thyroid thyroglobulin was injected into thyroidectomized rats. The density of thyroglobulin remained unchanged for 25 h during which time it was metabolized by more than 97%. Therefore, selective metabolism of thyroglobulin based on iodine content did not occur. We conclude that TSH causes a marked increase in the iodine content of circulating thyroglobulin. It is most likely that in the basal state circulating thyroglobulin comes from selective release of poorly iodinated molecules, while after TSH, it comes from release of previously synthesized, iodinated and stored molecules. 相似文献
7.
Arthur B. Schneider Kirsten Fleischmann Lily Chu 《Biochimica et Biophysica Acta (BBA)/General Subjects》1985,838(3):329-334
In previous work we demonstrated that circulating thyroglobulin contains very little or no iodine. We have now characterized circulating thyroglobulin following administration of thyrotropin (TSH) to determine whether its iodine content remains low or increases after stimulation. The iodine content of circulating thyroglobulin was estimated from its density determined by equilibrium density gradient (isopycnic) centrifugation. TSH stimulated thyroglobulin from 182 ± 28 ng/ml to 571 ± 83 ng/ml at 8–14 h. Circulating thyroglobulin in the basal state had a density consistent with very little or no iodine. Its density increased following TSH to a maximum at 8–14 h which was nearly the same as the density of thyroglobulin extracted directly from the thyroid. To determine whether selective peripheral metabolism, based on the degree of iodination, could account for the density shift, purified rat thyroid thyroglobulin was injected into thyroidectomized rats. The density of thyroglobulin remained unchanged for 25 h during which time it was metabolized by more than 97%. Therefore, selective metabolism of thyroglobulin based on iodine content did not occur. We conclude that TSH causes a marked increase in the iodine content of circulating thyroglobulin. It is most likely that in the basal state circulating thyroglobulin comes from selective release of poorly iodinated molecules, while after TSH, it comes from release of previously synthesized, iodinated and stored molecules. 相似文献
8.
Though sex steroids are found to influence thyroid pathogenesis in human and in animals, their role in normal thyroid growth and thyrocyte proliferation is not yet understood fully. The present study is addressed to know the effect of testosterone and estradiol on the basal and TSH-induced thyrocyte proliferation in immature and adult rats in vitro. The male and female Wistar rats were gonadectomized (GDX) and one group of GDX rats were supplemented with either testosterone or estradiol. After the experimental period, the rats were sacrificed by decapitation and thyroid glands were removed, washed in Hank's Balanced Salt Solution (HBSS), pH 7.4 and digested with the enzyme mixture containing 0.08% collagenase and 0.12% dispase in HBSS. The isolated follicles were washed thrice with Dulbecco's modified Eagle's medium (DMEM) containing 0.5% fetal bovine serum (FBS), and were cultured in Falcon's tissue culture flasks containing 5 ml DMEM with FBS (5%) transferrin (5 microg/ml), hydrocortisone (10(-8) M), somatostatin (10 microg/ml), insulin (10 microg/ml) and glycyl-L-histidyl-L-lysine acetate (10 microg/ml). The cells (2.5 x 10(4)) were exposed to various exponential doses of TSH or testosterone (6.25-800 ng/ml) or estradiol (6.25-800 pg/ml). It is suggested from the present study that both TSH and sex steroids enhance thyrocyte proliferation. The mitogenic effect of TSH is greater than that of sex steroids. Sex steroids modulate TSH-induced cell proliferation in a gender-specific manner. 相似文献
9.
Using sheep thyroid cells in culture, we have studied the effects of thyroid stimulating hormone (TSH), epidermal growth factor (EGF) and the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA) on the activity and expression of both thyroglobulin (Tg) and thyroid peroxidase (TPO) and on the ability of cells to trap and organify iodide. Using Western blotting techniques, we found that TSH increased the absolute cellular levels of Tg. The optimum TSH concentration for Tg mRNA production was between 0.1-1.0 mU/ml. Thyroglobulin mRNA levels were stimulated by TSH but detectable levels were also present in cultures grown in its absence containing cortisol, insulin, transferrin, somatostatin and glycyl-lysyl-histidyl acetate. Unlike Tg, TPO protein levels were found to be completely dependent upon TSH. A time course of TSH stimulation of TPO mRNA showed increases after 8 h of TSH stimulation, whereas induction of Tg mRNA by TSH was seen at 24 h. Iodide trapping and organification were also TSH-dependent processes, showing maximum activities at 300-500 muU/ml of TSH. The addition of 10 nM TPA caused a biphasic decrease in radiolabeled pertechnetate uptake, with complete inhibition being seen at 14 h. Inhibition of iodide organification occurred more rapidly. TPA and EGF (1 nM) reduced the amount of newly synthesized Tg in TSH-stimulated cells by 50% but the absolute amount of Tg within the cells was not markedly inhibited at these early times.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
L Hyldahl 《Cell biology international reports》1985,9(7):655-662
Substantial multiplication of stromal cells from human embryonic corneas has been obtained in a basal medium MCDB 104 supplemented with 25 ng EGF/ml, 10 micrograms insulin/ml, 20 micrograms transferrin/ml, 25 ng MSA/ml, 500 micrograms ovalbumin/ml, 50 micrograms LDL/ml, 50 micrograms HDL/ml and 10(-6) M hydrocortisone. Even though the growth rate appears to be similar to that in 10% serum, the cells cease proliferating at a lower density. 相似文献
11.
Yasuhiro Tomooka Stephen E. Harris John A. McLachlan 《In vitro cellular & developmental biology. Plant》1985,21(4):237-244
Summary Epithelial cells from mouse seminal vesicles were enzymatically dissociated enriched by gradient centrifugation, and maintained
in collagen gel cultures with defined (serum-free) media. The epithelial origin of the cells was determined morhologically,
immunocytochemically, and biochemically. Cells formed three-dimensional colonies with a lumen in collagen gels. Cell number
was increased eight-fold within a 8 to 12-d culture period in a medium supplemented with epidermal growth factor (EGF) (10
ng/ml), insulin (10 μg/ml), transferrin (10 μg/ml), cholera toxin (10 ng/ml), and hydrocortisone (0.1 μg/ml). The cells required
eGF and insulin; the growth-promoting effects of these two peptide hormones were optimized by transferrin, cholera toxin,
and hydrocortisone. Fetal bovine serum did not support growth; rather, it suppressed the stimulated growth observed in serum-free
media. A time-course study revealed that a lag period preceded rapi growth. The collagen gel, serum-free culture provides
a powerful tool to study the effects of hormones on proliferation and differentiation of androgen sensitive cells. 相似文献
12.
The serum thyroglobulin (Tg) concentration was measured in 97 patients with diabetes mellitus (39 males, 58 females). Hyper Tg-nemia which exceeds the normal range (1.0-26.6 ng/ml) was observed in 10 patients (3 out of 21 cases treated with diet alone, 3 out of 50 cases treated with oral hypoglycemic agents, 4 out of 26 cases treated with insulin). There was no significant correlation between concentrations of serum Tg and triiodothyronine (T3), thyroxine (T4), fasting plasma glucose (FPG), and hemoglobin A1c (HbA1c). However, a positive correlation was observed between serum concentrations of Tg and thyroid stimulating hormone (TSH). Patients with diabetes were divided into three groups according to the mode of treatment (Group I; diet alone, n = 21, Group II; oral hypoglycemic agents, n = 50, Group III; insulin, n = 26). No significant difference in the serum Tg concentration was observed among the three groups. They were also divided into two groups; normal Tg-nemia (Group A, n = 87) and hyper Tg-nemia (Group B, n = 10). There was no difference between levels of T3, T4, FPG, and HbA1c in the two groups. The serum TSH concentration measured by double antibody RIA and two site immunoradiometric assay in Group B was significantly higher than that in Group A. These results suggest that hyper Tg-nemia in patients with diabetes could be due to the increased TSH concentration which reflects latent subclinical primary hypothyroidism in them. 相似文献
13.
O Isozaki L D Kohn C A Kozak S Kimura 《Molecular endocrinology (Baltimore, Md.)》1989,3(11):1681-1692
A rat thyroid peroxidase cDNA has been isolated from a FRTL-5 thyroid cell library and sequenced. The cDNA is 2776 base pairs long with an open reading frame of 770 amino acids. By comparison to full-length human thyroid peroxidase cDNA and based on its identification of a 3.2 kilobase mRNA in rat thyroid FRTL-5 cell Northern blots, the rat peroxidase cDNA appears to lack 400-500 base pairs at the 5'-end of the mRNA. It exhibits only a 74% nucleotide and 77% amino acid sequence similarity to human thyroid peroxidase cDNA within the total aligned sequences, although the predicted active site regions are highly conserved (greater than 90-100%). The cDNA has been used to map the thyroid peroxidase gene in mice to chromosome 12 and to compare thyroid peroxidase and thyroglobulin gene expression in FRTL-5 rat thyroid cells. Despite the fact TSH action in both cases is duplicated, and presumably mediated, by cAMP, TSH-induced increases in thyroid peroxidase and thyroglobulin mRNA levels differ. Differences exist with respect to hormone concentration and time. The ability of TSH to increase thyroglobulin, but not thyroid peroxidase mRNA levels, requires insulin, 5% serum, or insulin-like growth factor-I. Insulin or insulin-like growth factor-I alone can increase thyroglobulin mRNA levels as well as or better than TSH but have only a small effect on thyroid peroxidase mRNA levels by comparison to TSH. The ability of TSH to increase thyroglobulin gene expression is readily detected in nuclear run-on assays but not the ability of TSH to increase thyroid peroxidase gene expression. Cycloheximide inhibits TSH-increased thyroglobulin but not peroxidase mRNA levels. Finally, methimazole and phorbol 12-myristate 13-acetate show different effects on TSH-induced increases in thyroglobulin and thyroid peroxidase mRNA levels. 相似文献
14.
Mammary epithelial cells were prepared by collagenase digestion of tissue from mid-pregnant rabbits and cultured for up to 6 days on either collagen gels or an extracellular matrix prepared from the same tissue. The behaviour of the cells in serum-supplemented medium containing combinations of insulin, prolactin, hydrocortisone, estradiol and progesterone were monitored by measuring rates of casein synthesis, lactose synthesis, DNA synthesis and protein degradation. After 6 days, epithelial cells on floating collagen gels showed substantial increases in casein synthesis and DNA synthesis over freshly-prepared cells, following a decline during the first 3 days when the collagen gels are contracting. The optimum hormone combination for casein synthesis was insulin + prolactin + hydrocortisone, whereas for optimum DNA synthesis the additional presence of estradiol and progesterone was required. Cells on extracellular matrix showed increased rates of both casein synthesis and DNA synthesis by day 6 in the presence of insulin + prolactin + hydrocortisone, with additional estradiol + progesterone having an inhibitory effect. Whereas on day 2 rates of intracellular protein degradation were generally lower in cells on extracellular matrix, by day 6 rates of protein degradation were lowest in cells cultured on collagen gels with insulin + prolactin + hydrocortisone. In all cases, rates of lactose synthesis fell to low levels as the culture proceeded. Pulse-chase labelling of freshly-prepared cells with [32P]orthophosphate in medium containing serum and insulin + prolactin + hydrocortisone demonstrated that newly-synthesized casein was degraded during its passage through the epithelial cell. The influences of the collagen gels and extracellular matrix and of the hormone combinations on epithelial cell differentiation and secretory activity are discussed. 相似文献
15.
16.
An inexpensive enzyme immunoassay method was designed for the determination of thyroglobulin concentration in human blood serum. The range of concentrations of thyroglobulin which can be measured by the method is between 6 and 800 ng/ml. The sensitivity of the method is comparable to that of the commercial test kits. The values of thyroglobulin concentration obtained with the use of the described method are strongly correlated (r = 0.946) with those obtained by using the reference method (IRMA kit of Byk, Sweden). The intraassay coefficient of variation ranged from 5.5 to 10.2% and interassay coefficient of variation from 9.5 to 13.2% depending on the thyroglobulin concentration. The upper limit of blood serum thyroglobulin concentration in healthy subjects was 70 ng/ml. The results of thyroglobulin determination obtained with the described method are falsely lowered in the presence of antithyroglobulin antibodies; simultaneous determination of these antibodies is thus necessary in such a case. It seems that the described method may be used for monitoring the patients after surgical treatment of differentiated thyroid cancer aimed at early detection of metastases. 相似文献
17.
In a study of the effects of hydrocortisone on the embryonic chicken cartilage somatomedin assay, in the absence and in the presence of normal human reference serum (NHRS), it was found that: (1) The basal uptake of 35S into chicken embryo pelvic cartilage was reduced when hydrocortisone hemisuccinate was added to the incubation medium in concentrations ranging from 1.5 to 1.5 X 10(5) ng/ml. There was a correlation between the inhibitory effect and the quantity of hydrocortisone added (r=-0.869; p less than 0.01). (2) The 35S uptake stimulated by 1.25 and 5% serum present in the incubation medium was reduced by hydrocortisone in a final concentration range of 150-1.5 X 10(5) ng/ml incubation medium. The minimal dose was 1,000 times that required to affect the basal 35S uptake. (3) When hydrocortisone was directly added to the NHRS, its interfering effect on the 35S uptake stimulated by 1.25, 5 and 20% of serum in the incubation medium was demonstrable with 5 X 10(5) ng hydrocortisone/ml serum. This concentration exceeded the physiological level of hydrocortisone by a factor of 5,000. 相似文献
18.
INTRODUCTION: The aim of the study was to estimate the influence of a thyroid remnants' volume, postsurgical concentration of thyroglobulin and radioiodine dose on the early treatment efficacy of well differentiated thyroid cancer. MATERIAL AND METHODS: We retrospectively analyzed 91 patients (76 females, 15 men) with well differentiated thyroid cancer. RESULTS: Histological classification revealed 68.1% (62/91) papillary thyroid cancers, 25.3% (23/91) follicular thyroid cancers, and 6.6% (6/91) oxyphilic thyroid cancers. Among the group, 74 (81.3%) patients reached the remission criteria and the remaining 17 patients (18.7%) showed biochemical and morphological evidence of metastatic disease. The remission was obtained in 100% of patients in stage I of the disease, 68.4% - in stage II, 78.6% - in stage III and 33.3% in stage IV. The total radioiodine dose used in patients with remission, did not differ from the dose used in patients without remission. We did not observe the influence of remnant's volume on treatment efficacy, however larger remants required higher dose of radioiodine to obtain the remission. Patients with remission had lower postsurgical thyroglobulin concentration than patients without remission. (22.2 vs. 103.3 ng/ml; p = 0.00025). CONCLUSIONS: Early treatment results of well differentiated thyroid cancer depend on the clinical stage, and postoperative serum thyroglobulin level measured after endogenous TSH stimulation. Early treatment results are not dependent on age, sex, histological type of thyroid cancer, the dose of radioiodine used in brackets of 60-150 mCi and additional diseases. Total thyroidectomy is equally efficient as near total. 相似文献
19.
K Hosokawa H Yamaguchi T Ikehara A Takahashi H Miyamoto 《Journal of cellular physiology》1990,144(2):254-261
The influence of the intracellular K+ concentration on the effects of growth factors (insulin, EGF, hydrocortisone, and transferrin) and LDL on growth of HeLa cells was investigated. Upon replacement of K+ in a chemically defined medium (K(+)-CDM) by Rb+ (Rb(+)-CDM), about 80% of the intracellular K+ was replaced by Rb+ within 24 h, but showed no further change in the next 24 h, irrespective of addition of dialyzed calf serum (5%) or growth factors to the medium. In Rb(+)-CDM, cell growth and DNA synthesis were greatly suppressed, although cell viability was not significantly altered for 72 h. The suppression of cell growth was partially restored by addition of serum, insulin (5 micrograms/ml), or LDL (2.5 mg/ml) to Rb(+)-CDM. A combination of serum and insulin or insulin and LDL stimulated cell growth to approximately the level in K(+)-CDM without any addition, but a combination of serum and LDL did not have more effect than that of serum alone. Unexpectedly, other factors were ineffective in stimulating growth in Rb(+)-CDM. In Rb(+)-CDM, the effect of insulin was lost in 24-48 h, whereas that of LDL persisted for at least 96 h. Insulin and LDL also enhanced growth in K(+)-CDM. After cessation of cell growth in Rb(+)-CDM for 24 h, addition of insulin and/or LDL markedly restored cell growth and DNA synthesis. Therefore, insulin and LDL may stimulate certain mechanisms required for cell growth that can operate in K(+)-deficient conditions. 相似文献
20.
Brigitte A. van der Haegen Richard G. Ham Tamiko Kano-Sueoka 《In vitro cellular & developmental biology. Plant》1989,25(2):151-157
Summary An improved serum-free medium has been developed that supports growth of rat mammary tumor line 64–24 with far less protein
supplementation and with a much smaller inoculum than previously possible. An initial survey showed that MCDB 202 supported
clonal growth with 1% dialyzed serum. The remaining serum was then replaced with 5 μg/ml insulin, 10 ng/ml epidermal growth
factor (EGF), 1 μg/ml hydrocortisone, 50 ng/ml ovine prolactin, and 5 μg/ml liposome B (a mixture of soy lecithin, sphingomyelin,
cholesterol, vitamin E, and vitamin E acetate in liposome form). Insulin and EGF are required and growth is improved by hydrocortisone
and prolactin. Estradiol is stimulatory in the absence of liposome B. With adequate iron supplementation, transferrin has
no effect. Liposome B increases growth rate substantially. Most of the growth stimulation can be replaced with phosphatidylethanolamine
or sphingomyelin.
This paper contains material from a thesis submitted to the Graduate School of the University of Colorado, Boulder, by B.A.VdH.
in partial fulfillment of the requirements for the Ph.D. degree. This research was supported by grant CA-15305 to R.G.H. and
grant CA-30545 to T.K.-S., both from the National Institutes of Health, Bethesda, MD. 相似文献