Prolonged hypothyroidism severely reduces ovarian follicular reserve in adult rats

Background There is substantial evidence both in humans and in animals that a prolonged reduction in plasma thyroid hormone concentration leads to reproductive problems, including disturbed folliculogenesis, impaired ovulation and fertilization rates, miscarriage and pregnancy complications. The objective of the present study is to examine the consequences of chronic hypothyroidism, induced in adulthood, for the size of the ovarian follicle pool. In order to investigate this, adult female rats were provided either a control or an iodide deficient diet in combination with perchlorate supplementation to inhibit iodide uptake by the thyroid. Sixteen weeks later animals were sacrificed. Blood was collected for hormone analyses and ovaries were evaluated histologically. Results At the time of sacrifice, plasma thyroid-stimulating hormone concentrations were 20- to 40-fold increased, thyroxine concentrations were negligible while tri-iothyronin concentrations were decreased by 40% in the hypothyroid group, confirming that the animals were hypothyroid. Primordial, primary and preantral follicle numbers were significantly lower in the hypothyroid ovaries compared to the euthyroid controls, while a downward trend in antral follicle and corpora lutea numbers was observed. Surprisingly the percentage of atretic follicles was not significantly different between the two groups, suggesting that the reduced preantral and antral follicle numbers were presumably not the consequence of increased degeneration of these follicle types in the hypothyroid group. Plasma anti-Müllerian hormone (AMH) levels showed a significant correlation with the growing follicle population represented by the total ovarian number of primary, preantral and antral follicles, suggesting that also under hypothyroid conditions AMH can serve as a surrogate marker to assess the growing ovarian follicle population. Conclusions The induction of a chronic hypothyroid condition in adult female rats negatively affects the ovarian follicular reserve and the size of the growing follicle population, which may impact fertility

Dual Effect on Adult-Type Leydig Cell and Sertoli Cell Development

Transient neonatal 6-propyl-2-thiouracil (PTU) induced hypothyroidism affects Leydig and Sertoli cell numbers in the developing testis, resulting in increased adult testis size. The hypothyroid condition was thought to be responsible, an assumption questioned by studies showing that uninterrupted fetal/postnatal hypothyroidism did not affect adult testis size. Here, we investigated effects of transient hypothyroidism on Leydig and Sertoli cell development, employing a perinatal iodide-deficient diet in combination with sodium perchlorate. This hypothyroidism inducing diet was continued until days 1, 7, 14, or 28 postpartum (pp) respectively, when the rats were switched to a euthyroid diet and followed up to adulthood. Continuous euthyroid and hypothyroid, and neonatal PTU-treated rats switched to the euthyroid diet at 28 days pp, were included for comparison. No effects on formation of the adult-type Leydig cell population or on Sertoli cell proliferation and differentiation were observed when the diet switched at/or before day 14 pp. However, when the diet was discontinued at day 28 pp, Leydig cell development was delayed similarly to what was observed in chronic hypothyroid rats. Surprisingly, Sertoli cell proliferation was 6- to 8-fold increased 2 days after the diet switch and remained elevated the next days. In adulthood, Sertoli cell number per seminiferous tubule cross-section and consequently testis weight was increased in this group. These observations implicate that increased adult testis size in transiently hypothyroid rats is not caused by the hypothyroid condition per se, but originates from augmented Sertoli cell proliferation as a consequence of rapid normalization of thyroid hormone concentrations

The effect of nasal steroid aqueous spray on nasal complaint scores and cellular infiltrates in the nasal mucosa of patients with nonallergic, noninfectious perennial rhinitis

Topical corticosteroids are the therapy of choice for nonallergic, noninfectious perennial rhinitis (NANIPER). However, the efficacy of steroid therapy in NANIPER is controversial, as is its mode of action. To our surprise, of 300 patients initially diagnosed as having NANIPER, only 65 reached threshold nasal symptom scores. Patients were randomized into four different treatment regimens: placebo administered twice daily (BD) for 8 weeks, fluticasone propionate aqueous nasal spray (FPANS) (200 microg) once daily (OD) and placebo OD for 8 weeks, FPANS (200 microg) OD and placebo OD for 4 weeks followed by FPANS (200 microg) BD for 4 weeks, and FPANS (200 microg) BD for 8 weeks. A small decrease in nasal symptoms was found, which only reached significance for sneezing in the FPANS 200 microg BD group. A significant dose-dependent decrease in immunocompetent cells was found in nasal biopsy specimens obtained before, after 4 weeks, and after 8 weeks of treatment. We conclude that FPANS did not significantly reduce nasal symptoms in this group of selected NANIPER patients, even though a significant effect on cells in the nasal mucosa was see

Oncostatin-M inhibits luteinizing hormone stimulated Leydig cell progenitor formation in vitro

Background: The initial steps of stem Leydig cell differentiation into steroid producing progenitor cells are thought to take place independent of luteinizing hormone (LH), under the influence of locally produced factors such as leukaemia inhibitory factor (LIF), platelet derived growth factor A and stem cell factor. For the formation of a normal sized Leydig cell population in the adult testis, the presence of LH appears to be essential. Oncostatin M (OSM) is a multifunctional cytokine and member of the interleukin (IL)-6 family that also includes other cytokines such as LIF. In the rat OSM is highly expressed in the late fetal and neonatal testis, and may thus be a candidate factor involved in Leydig cell progenitor formation. Methods: Interstitial cells were isolated from 13-day-old rat testes and cultured for 1, 3 or 8 days in the presence of different doses of OSM ( range: 0.01 to 10 ng/ml) alone or in combination with LH ( 1 ng/ml). The effects of OSM and LH on cell proliferation were determined by incubating the cultures with [3H] thymidine or bromodeoxyuridine ( BrdU). Developing progenitor cells were identified histochemically by the presence of the marker enzyme 3beta-hydroxysteroid dehydrogenase (3beta-HSD). Results: OSM, when added at a dose of 10 ng/ml, caused a nearly 2-fold increase in the percentage of Leydig cell progenitors after 8 days of culture. Immunohistochemical double labelling experiments with 3beta-HSD and BrdU antibodies showed that this increase was the result of differentiation of stem Leydig cells/precursor cells and not caused by proliferation of progenitor cells themselves. The addition of LH to the cultures consistently resulted in an increase in progenitor formation throughout the culture period. Surprisingly, when OSM and LH were added together, the LH induced rise in progenitor cells was significantly inhibited after 3 and 8 days of culture. Conclusion: Taken together, the results of the present study suggest that locally produced OSM may not only play a role in the regulation of Sertoli cell proliferation and the initiation of spermatogenesis but may also play a role in the regulation of Leydig cell progenitor formation by keeping the augmenting effects of LH on this process in abeyance

Establishment of an Effective Radioiodide Thyroid Ablation Protocol in Mice

Due to the high variance in available protocols on iodide-131 ((131)I) ablation in rodents, we set out to establish an effective method to generate a thyroid-ablated mouse model that allows the application of the sodium iodide symporter (NIS) as a reporter gene without interference with thyroidal NIS. We tested a range of (131)I doses with and without prestimulation of thyroidal radioiodide uptake by a low-iodine diet and thyroid-stimulating hormone (TSH) application. Efficacy of induction of hypothyroidism was tested by measurement of serum T4 concentrations, pituitary TSH\textgreekb and liver deiodinase type 1 (DIO1) mRNA expression, body weight analysis, and (99m)Tc-pertechnetate scintigraphy. While 200 µCi (7.4 MBq) (131)I alone was not sufficient to abolish thyroidal T4 production, 500 µCi (18.5 MBq) (131)I combined with 1 week of a low-iodine diet decreased serum concentrations below the detection limit. However, the high (131)I dose resulted in severe side effects. A combination of 1 week of a low-iodine diet followed by injection of bovine TSH before the application of 150 µCi (5.5 MBq) (131)I decreased serum T4 concentrations below the detection limit and significantly increased pituitary TSH\textgreekb concentrations. The systemic effects of induced hypothyroidism were shown by growth arrest and a decrease in liver DIO1 expression below the detection limit. (99m)Tc-pertechnetate scintigraphy revealed absence of thyroidal (99m)Tc-pertechnetate uptake in ablated mice. In summary, we report a revised protocol for radioiodide ablation of the thyroid gland in the mouse to generate an in vivo model that allows the study of thyroid hormone action using NIS as a reporter gene

Next-generation sequencing of immunoglobulin gene rearrangements for clonality assessment: a technical feasibility study by EuroClonality-NGS

Item does not contain fulltex

Testing for heterotopia formation in rats after developmental exposure to selected in vitro inhibitors of thyroperoxidase

© 2021 The Authors. The thyroperoxidase (TPO) enzyme is expressed by the thyroid follicular cells and is required for thyroid hormone synthesis. In turn, thyroid hormones are essential for brain development, thus inhibition of TPO in early life can have life-long consequences for brain function. If environmental chemicals with the capacity to inhibit TPO in vitro can also alter brain development in vivo through thyroid hormone dependent mechanisms, however, remains unknown. In this study we show that the in vitro TPO inhibiting pesticide amitrole alters neuronal migration and induces periventricular heterotopia; a thyroid hormone dependent brain malformation. Perinatal exposure to amitrole reduced pup serum thyroxine (T4) concentrations to less than 50% of control animals and this insufficiency led to heterotopia formation in the 16-day old pup's brain. Two other in vitro TPO inhibitors, 2-mercaptobenzimidazole and cyanamide, caused reproductive toxicity and had only minor sporadic effects on the thyroid hormone system; consequently, they did not cause heterotopia. This is the first demonstration of an environmental chemical causing heterotopia, a brain malformation until now only reported for rodent studies with the anti-thyroid drugs propylthiouracil and methimazole. Our results highlight that certain TPO-inhibiting environmental chemicals can alter brain development through thyroid hormone dependent mechanisms. Improved understanding of the effects on the brain as well as the conditions under which chemicals can perturb brain development will be key to protect human health.ATHENA project (Assays for the identification of Thyroid Hormone axis-disrupting chemicals: Elaborating Novel assessment strategies); (Kortenkamp et al., 2020) funded by the EU Horizon 2020 programme, grant number 825161

Quality control and quantification in IG/TR next-generation sequencing marker identification: protocols and bioinformatic functionalities by EuroClonality-NGS

Assessment of clonality, marker identification and measurement of minimal residual disease (MRD) of immunoglobulin (IG) and T cell receptor (TR) gene rearrangements in lymphoid neoplasms using next-generation sequencing (NGS) is currently under intensive development for use in clinical diagnostics. So far, however, there is a lack of suitable quality control (QC) options with regard to standardisation and quality metrics to ensure robust clinical application of such approaches. The EuroClonality-NGS Working Group has therefore established two types of QCs to accompany the NGS-based IG/TR assays. First, a central polytarget QC (cPT-QC) is used to monitor the primer performance of each of the EuroClonality multiplex NGS assays; second, a standardised human cell line-based DNA control is spiked into each patient DNA sample to work as a central in-tube QC and calibrator for MRD quantification (cIT-QC). Having integrated those two reference standards in the ARResT/Interrogate bioinformatic platform, EuroClonality-NGS provides a complete protocol for standardised IG/TR gene rearrangement analysis by NGS with high reproducibility, accuracy and precision for valid marker identification and quantification in diagnostics of lymphoid malignancies.This work was supported by Ministry of Health of the Czech Republic, grant no. 16-34272A; computational resources were provided by the CESNET LM2015042 and the CERIT Scientific Cloud LM2015085, provided under the programme “Projects of Large Research, Development, and Innovations Infrastructures”. Analyses in Prague (JT, EF and MS) were supported by Ministry of Health, Czech Republic, grant no. 00064203, and by PRIMUS/17/MED/11. Analyses in the Monza (Centro Ricerca Tettamanti, SS, AG and GC) laboratory were supported by the Italian Association for Cancer Research (AIRC) and Comitato Maria Letizia Verga

Analysis of differential gene expression in human melanocytic tumour lesions by custom made oligonucleotide arrays

Melanoma is one of the most aggressive types of cancer and resection of the tumour prior to dissemination of tumour cells is still the most effective treatment. Therefore, early diagnosis of melanocytic lesions is important and identification of novel (molecular) markers would be helpful to improve diagnosis. Moreover, better understanding of molecular targets involved in melanocytic tumorigenesis could possibly lead to development of novel interventions. In this study, we used a custom made oligonucleotide array containing 298 genes that were previously found to be differentially expressed in human melanoma cell lines 1F6 (rarely metastasising) and Mel57 (frequently metastasising). We determined differential gene expression in human common nevocellular nevus and melanoma metastasis lesions. By performing nine dye-swap array experiments, using individual as well as pooled melanocytic lesions, a constant differential expression could be detected for 25 genes in eight out of nine or nine out of nine array analyses. For at least nine of these genes, namely THBD, FABP7, H2AFJ, RRAGD, MYADM, HR, CKS2, NCK2 and GDF15, the differential expression found by array analyses could be verified by semiquantitative and/or real-time quantitative RT–PCR. The genes that we identified to be differentially expressed during melanoma progression could be potent targets for diagnostic, prognostic and/or therapeutic interventions