- C. Hardeveld (1)
- D. Heide van der (2)
- M. Karperien (1)
- T. Lende van der (1)
- S.C. Liefers (1)
- C.G. Linden van der (1)
- A. Muller (1)
- A.P. Palstra (1)
- M.F.W. Pas te (1)
- D.S. Penaranda (1)
- L. Perez (1)
- I. Que (1)
- J.A. Romijn (2)
- J.P. Schroder-van der Elst (1)
- W.S. Simonides (1)
- J.W.A. Smit (2)
- M. Stokkel (1)
- M.H.M. Thelen (1)
- G.E.E.J.M. Thillart (1)
- R.F. Veerkamp (1)
Influence of temperature regime on endocrine parameters and vitellogenesis during experimental maturation of European eel (Anguilla anguilla) females
Perez, L. ; Penaranda, D.S. ; Dufour, S. ; Baloche, S. ; Palstra, A.P. ; Thillart, G.E.E.J.M. ; Asturiano, J.F. - \ 2011
General and Comparative Endocrinology 174 (2011)1. - ISSN 0016-6480 - p. 51 - 59.
messenger-rna levels - glycoprotein hormone alpha - goldfish carassius-auratus - trout oncorhynchus-mykiss - induced sexual-maturation - conger conger-myriaster - ii-beta subunits - japanese eel - luteinizing-hormone - artificial maturation
We examined the effect of temperature in European silver eels during their maturation induced by injections of carp pituitary extract on endocrine parameters: pituitary fshß and lhß expression, plasma 17ß-estradiol (E2) and vitellogenin, estrogen receptor 1 (esr1), and vitellogenin 2 (vtg2) expression in liver. A variable thermal regime (T10) that increased from 10° to 14° and 17°C was compared with a constant 20°C regime (T20) during 12weeks. T10 caused a faster development until week 8, higher fshß, lhß, esr1 expression, and higher E2 levels. The results strongly suggest that T10 is inducing a higher endogenous FSH level which increases the E2 circulating level during vitellogenesis. A variable thermal regime induced an fshß expression and E2 profile in vitellogenic hormonally matured eel females that were more similar to the profile observed in other naturally maturing fish
Genetics and physiology of leptin in periparturient dairy cows
Liefers, S.C. ; Veerkamp, R.F. ; Pas, M.F.W. te; Chilliard, Y. ; Lende, T. van der - \ 2005
Domestic Animal Endocrinology 29 (2005)1. - ISSN 0739-7240 - p. 227 - 238.
recombinant ovine leptin - messenger-rna levels - plasma leptin - luteinizing-hormone - adipose-tissue - feed-intake - serum concentrations - energy-balance - bovine adenohypophysis - circulating leptin
In dairy cattle, the increase in milk yield has been accompanied by a more negative energy balance (EB) during early lactation and a decrease in fertility. As the hormone leptin is involved in regulation of nutritional status and reproductive function this hormone is an interesting protein to investigate during the periparturient period in dairy cattle. This study was performed to get insight into the function of leptin during the periparturient period and to perform an association study between polymorphisms in the bovine leptin gene and leptin receptor gene and fertility as well as production traits. Leptin concentrations in the periparturient cow undergo remarkable changes; leptin concentrations were high during late pregnancy and declined to a nadir at parturition. Genetic analysis of the leptin gene indicated that a combination of three polymorphisms located at a 135 bp region of the leptin promoter explained most of the variance in prepartum leptin concentrations. The two extreme genotype combinations could be used to investigate the function of leptin concentrations in pregnant cows. A polymorphism located on intron 2 of the leptin gene explained a significant part of the variation in milk yield. On the promoter region of the leptin gene an SNP was detected that was associated with first postpartum luteal activity (FPLA). This SNP could be a candidate marker for fertility in dairy cows. Another SNP on the leptin promoter was associated with energy balance and dry matter intake (DMI) where a higher dry matter intake occurred together with a higher energy balance. Two genotype combinations of the aforementioned three associated SNPs were defined which had a good milk yield together with a good energy balance and fertility. Calculations of an economical value per trait have to validate if one of these genotype combinations would be a possible candidate to be used in selection.
Differential effects of natural flavonoids on growth and iodide content in a human NA+/I_symporter-transfecred follicular thyroid carcinoma cell line
Schroder-van der Elst, J.P. ; Heide, D. van der; Romijn, J.A. ; Smit, J.W.A. - \ 2004
European Journal of Endocrinology 150 (2004)4. - ISSN 0804-4643 - p. 557 - 564.
messenger-rna levels - sodium/iodide symporter - cancer - rat - expression - transporter - emd-21388 - transthyretin - strategies - inhibition
OBJECTIVE: Natural flavonoids (plant pigments) have been shown to inhibit thyroid peroxidase (TPO) in vitro and the growth of thyroid cancer cell lines. We have studied the role of flavonoids on the iodide transport and the growth of the human follicular thyroid cancer cell line (FTC133) which was stably transfected with the human Na(+)/I(-) symporter (hNIS). DESIGN AND METHODS: Cells were treated with flavonoids (0.5-50 microM) for 0, 2, 4 and 6 days; (125)I content and (125)I efflux of the cells and DNA content were measured. RESULTS: Cell growth was inhibited significantly at day 6 by most flavonoids. Eight out of ten flavonoids decreased the (125)I content of the cells at day 4. Morin did not influence the (125)I content of the cells and, surprisingly, myricetin increased the (125)I content of the cells. Kaempferol, apigenin, luteolin and F21388 decreased NIS mRNA expression after 15, 29 and 48 h; after 96 h NIS mRNA returned to normal. CONCLUSION: As TPO is not present in this cell line, the effects of the flavonoids on the iodide uptake are not related to organification. Myricetin was the only flavonoid studied that increased the influx and decreased the efflux of iodide. The effect of myricetin (decreased growth and increased retention of iodide) can be of therapeutic value in the radioiodide treatment of thyroid carcinoma
Iodide kinetics and experimental I-131 therapy in a xenotransplanted human sodium-iodide symporter-transfected human follicular thyroid carcinoma cell line
Smit, J.W.A. ; Elst, J.P. van der; Karperien, M. ; Que, I. ; Stokkel, M. ; Heide, D. van der; Romijn, J.A. - \ 2002
Journal of Clinical Endocrinology and Metabolism 87 (2002)3. - ISSN 0021-972X - p. 1247 - 1253.
messenger-rna levels - sodium/iodide symporter - radioiodine therapy - prostate-cancer - retinoic acid - frtl-5 cells - expression - gene - hormone - cloning
Uptake of iodide is a prerequisite for radioiodide therapy in thyroid cancer. However, loss of iodide uptake is frequently observed in metastasized thyroid cancer, which may be explained by diminished expression of the human sodium-iodide symporter (hNIS). We studied whether transfection of hNIS into the hNIS-deficient follicular thyroid carcinoma cell line FTC133 restores the in vivo iodide accumulation in xenografted tumors and their susceptibility to radioiodide therapy. In addition, the effects of low-iodide diets and thyroid ablation on iodide kinetics were investigated. Tumors were established in nude mice injected with the hNIS-transfected cell line FTC133-NIS30 and the empty vector transfected cell line FTC133-V4 as a control. Tumors derived from FTC133-NIS30 in mice on a normal diet revealed a high peak iodide accumulation (17.4% of administered activity, measured with an external probe) as compared with FTC133-V4 (4.6%). Half-life in FTC133-NIS30 tumors was 3.8 h. In mice kept on a low-iodide diet, peak activity in FTC133-NIS30 tumors was diminished (8.1%), whereas thyroid iodide accumulation was increased. In thyroid-ablated mice kept on a low-iodide diet, half-life of radioiodide was increased considerably (26.3 h), leading to a much higher area under the time-radioactivity curve than in FTC133-NIS30 tumors in mice on a normal diet without thyroid ablation. Experimental radioiodide therapy with 2 mCi (74 MBq) in thyroid-ablated nude mice, kept on a low-iodide diet, postponed tumor development (4 wk after therapy, one of seven animals revealed tumor vs. five of six animals without therapy). However, 9 wk after therapy, tumors had developed in four of the seven animals. The calculated tumor dose was 32.2 Gy. We conclude that hNIS transfection into a hNIS-defective thyroid carcinoma cell line restores the in vivo iodide accumulation. The unfavorable iodide kinetic characteristics (short half-life) can be partially improved by conventional conditioning with thyroid ablation and low-iodide diet, leading to postponed tumor development after radioiodide therapy. However, to achieve sufficient radioiodide tumor doses for therapy, further strategies are necessary, aiming at the mechanisms of iodide efflux in particular
Mechanism of thyroid-hormone regulated expression of the SERCA genes in skeletal muscle: Implications for thermogenesis
Simonides, W.S. ; Thelen, M.H.M. ; Linden, C.G. van der; Muller, A. ; Hardeveld, C. - \ 2001
Bioscience Reports 21 (2001)2. - ISSN 0144-8463 - p. 139 - 154.
sarcoplasmic-reticulum ca2+-atpase - cold-acclimated ducklings - messenger-rna levels - heat-production - postnatal-development - differential expression - uncoupling protein - receptor isoforms - force development - twitch muscle
Thyroid hormone increases the Ca2+-ATPase activity of the sarcoplasmic reticulum (SR) in skeletal muscle, thereby increasing the energy-turnover associated with Ca2+-cycling during contraction and rest. The fast-muscle isoform of the Ca2+-ATPase (SERCA1) and the slow-muscle isoform (SERCA2a), are encoded by two genes that are transcriptionally regulated by T3. The SERCA1 isoform can be expressed to considerably higher levels than the SERCA2a isoform. The stimulation of transcription of the SERCA1 gene by T3 is mediated by two thyroid hormone response elements, located in the promoter of this gene. The intracellular [Ca2+] can modulate the effect of T3. The increase in SR Ca2+-ATPase activity seen when T3-levels rise above normal, results from the induction of SERCA1 expression in slow muscle fibers. Concomitant high levels of Ca2+-ATPase activity are associated with down-regulation of SERCA2a expression in these fibers. The observed T3-dependent increase in SERCA1 expression and associated Ca2+-ATPase activity will increase the overall metabolic rate of the organism significantly under normal conditions, because of the high average level of contractile activity of slow fibers. Given the rise in serum T3-levels during prolonged cold exposure, these data suggest that fiber-specific stimulation of SERCA1 expression contributes to the thermogenic response in non-shivering thermogenesis. This mechanism may be particularly relevant in larger mammals, which have a relatively high percentage of slow fibers in skeletal muscle, and which need to rely on tissues other than brown fat for the generation of extra heat