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G Aust
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M Steinert
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C Boltze
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S Kiessling
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C Simchen
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Thyroid glands affected by Graves' disease (GD) show striking leukocytic infiltration, mainly by T-cells. The mechanisms by which the various leukocytes are maintained in the thyroid are unknown. Growth-regulated oncogene-alpha (GRO-alpha) in interaction with its receptor CXCR2 is a chemoattractant for both T-cells and neutrophils and may be one of the chemokines involved in the cell maintenance. GRO-alpha and CD18 mRNA as a marker of leukocytic infiltration were quantified in thyroid tissue using competitive RT-PCR. We found very high GRO-alpha mRNA levels in all thyroid tissues. In GD patients (n=16), the GRO-alpha mRNA did not correlate with the CD18 mRNA level or thyroid peroxidase and TSH-receptor antibodies in patients' sera. In thyroid autonomy (n=10), the GRO-alpha mRNA levels were significantly lower in autonomous single adenomas compared with the corresponding normal tissue. In order to define the cellular source of GRO-alpha mRNA and protein, we examined various thyroid-derived cells. Thyrocytes, thyroid-derived leukocytes and fibroblasts showed basal GRO-alpha mRNA and protein expression, which was remarkably upregulated by different stimuli in vitro. The expression of GRO-alpha by thyroid carcinoma cell lines confirms that thyrocytes may actually produce GRO-alpha. As shown by flow cytometry and immunohistology, CD68+ monocytes/macrophages are the only cell population strongly expressing CXCR2 in the thyroid.

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M Holstad
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S Sandler
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In earlier studies it has been shown that prolactin (PRL) is a stimulating factor for the immune system, and it has been suggested that PRL might antagonize immunosuppressive effects of glucocorticoids. PRL has been reported to affect the cytokine secretion pattern, by elevating cytokine gene expression in macrophages, after the onset of sepsis. It also promotes the antibody response in mice where it increases the production of interferon-gamma (IFN-gamma) and inhibits interleukin-1 (IL-1) production. Due to these properties, PRL might influence the development of autoimmune type 1 diabetes. The aim of the present study was to examine the effects of two drugs; PRL and bromocriptine (BC) in vivo on the development of hyperglycemia and pancreatic insulitis in mice treated with multiple doses of streptozotocin (STZ) (40 mg/kg body weight, i.p.). The dopaminergic agonist BC is known to inhibit PRL secretion. In another set of experiments, the direct effects of PRL on the function of pancreatic islets exposed to STZ in vitro were studied. Mice treated with STZ became gradually hyperglycemic, and concomitant treatment with PRL (4 mg/kg body weight) for 21 days significantly reduced the elevation in blood glucose levels from day 10 onwards (P<0.05). Morphologic examinations of the pancreas on day 21 of mice receiving STZ injections revealed a marked insulitis, but only moderate insulitis in the STZ treated animals given PRL. BC administration (10 mg/kg body weight) in combination with STZ did not significantly affect the elevation in blood glucose levels or the insulitis. PRL or BC administration alone did not change the serum glucose concentration. This study indicates that PRL may affect hyperglycemia in the early phase of autoimmune diabetes. We suggest that it might be due to counteraction of autoimmune immunologic mechanisms and/or enhancement of beta-cell regeneration.

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A Siddiqi
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JM Burrin
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DF Wood
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JP Monson
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Hyperthyroidism is associated with increased bone resorption but the mechanisms by which thyroid hormone (T3) affects bone cell metabolism remain unclear. Recently it has been suggested that T3 stimulates osteoclastic resorption indirectly through the release of soluble mediators from osteoblasts. The aim of the present study was to investigate whether the T3-induced increase in bone resorption could be due to the regulation of cytokine production by human osteoblasts (hOb). The effects of T3 (1, 10, 100 nM) and IL-1 beta (100 U/ml) as the positive control were examined on cytokine protein release and mRNA levels in cultured hOb cell lines (MG63, SaOs-2), primary hOb and human bone marrow stromal (hBMS) cells. T3 increased IL-6 and IL-8 mRNA levels as well as IL-6 and IL-8 protein release into the culture media from MG63 and hBMS cells in a time- and dose-dependent manner. The maximal effect on protein release in hBMS cells occurred at 24 h with a dose of T3 10 nM (IL-6 5.5 +/- 1.1-fold above controls; IL-8 3.7 +/- 0.5-fold above controls, P < 0.05). At the same time, mRNA levels in hBMS cells were increased 6.2 +/- 0.8-fold for IL-6 (P < 0.05) and 5.7 +/- 0.8-fold for IL-8 (P < 0.05). Similar results were obtained in MG63 cells but no response was seen in SaOs-2 or hOb cells despite measurable basal production. Nor was there detectable regulation of IL-1 beta, IL-3, IL-11, IL-4 or granulocyte macrophage-colony stimulating factor by T3 in any cell type. In conclusion, T3 increases IL-6 and IL-8 production by MG63 and hBMS cells, suggesting that IL-6 and IL-8 may be T3-regulated genes in osteoblasts.

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DJ Hill
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J Petrik
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E Arany
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TJ McDonald
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TL Delovitch
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Interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) contribute to the initial stages of the autoimmune destruction of pancreatic beta cells. IL-1beta is released by activated macrophages resident within islets, and its cytotoxic actions include a stimulation of nitric oxide (NO) production and the initiation of apoptosis. Insulin-like growth factors (IGFs)-I and -II prevent apoptosis in non-islet tissues. This study investigated whether IGFs are cytoprotective for isolated islets of Langerhans from non-obese diabetic mice (NOD) mice exposed to cytokines. Pancreatic islets isolated from 5-6-week-old, pre-diabetic female NOD mice were cultured for 48 h before exposure to IL-1beta (1 ng/ml), TNF-alpha (5 ng/ml), IFN-gamma (5 ng/ml) or IGF-I or -II (100 ng/ml) for a further 48 h. The incidence of islet cell apoptosis was increased in the presence of each cytokine, but this was significantly reversed in the presence of IGF-I or -II (IL-1beta control 3.5+/-1.6%, IL-1beta 1 ng/ml 27.1+/-5.8%, IL-1beta+IGF-I 100 ng/ml 4.4+/-2.3%, P<0.05). The majority of apoptotic cells demonstrated immunoreactive glucose transporter 2 (GLUT-2), suggesting that they were beta cells. Islet cell viability was also assessed by trypan blue exclusion. Results suggested that apoptosis was the predominant cause of cell death following exposure to each of the cytokines. Co-incubation with either IGF-I or -II was protective against the cytotoxic effects of IL-1beta and TNF-alpha, but less so against the effect of IFN-gamma. Exposure to cytokines also reduced insulin release, and this was not reversed by incubation with IGFs. Immunohistochemistry showed that IGF-I was present in vivo in islets from pre-diabetic NOD mice which did not demonstrate insulitis, but not in islets with extensive immune infiltration. Similar results were seen for IGF-binding proteins (IGFBPs). These results suggest that IGFs protect pre-diabetic NOD mouse islets from the cytotoxic actions of IL-1beta, TNF-alpha and IFN-gamma by mechanisms which include a reduction in apoptosis.

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M Jevon
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A Sabokbar
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Y Fujikawa
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T Hirayama
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SD Neale
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J Wass
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NA Athanasou
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A number of bone diseases characterised by excessive osteolysis (e.g. osteoporosis and Paget's disease) exhibit a marked gender difference in prevalence and are more common in the elderly population. Bone resorption is carried out by osteoclasts, which are formed by fusion of circulating mononuclear precursor cells of haematopoietic origin. In this study, we have determined whether there are gender- and age-related differences in osteoclast formation from circulating precursors. Peripheral blood mononuclear cells (PBMCs) were co-cultured with UMR106 osteoblast-like cells in the presence of macrophage-colony stimulating factor (M-CSF) and 1,25 dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) or cultured alone in the presence of sRANKL (soluble receptor activator of nuclear factor kappa B ligand) and M-CSF. As assessed by the formation of tartrate resistant acid phosphatase (TRAP)-positive (TRAP(+)) and vitronectin receptor-positive (VNR(+)) multinucleated cells (MNCs), there was no difference in the number of circulating osteoclast precursors in males and females. Lacunar resorption carried out by osteoclasts formed from these precursors was generally increased in males compared with females (P=0.03). An increase in the number of TRAP(+) and VNR(+) MNCs formed from male PBMCs was noted in response to 1,25(OH)(2)D(3) (P<0.005). An increase in lacunar resorption in cultures of PBMCs (10(5) per well) from males was also noted in response to 10(-9) M 1,25(OH)(2)D(3) (P<0.05) and sRANKL (P=0.05), but not M-CSF. The addition of dexamethasone resulted in a marked increase in osteoclast formation and lacunar resorption in both males and females. Post-menopausal females and males of comparable age showed similar levels of osteoclastogenesis. Pre-menopausal women showed similar levels of osteoclastogenesis but less resorption (P=0.01) compared with males of comparable age. These results show that there are specific gender/age-related differences in osteoclast formation and bone resorption and have implications for evaluating osteoclastogenesis in skeletal diseases such as primary osteoporosis and Paget's disease.

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K Toda
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K Takeda
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T Okada
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S Akira
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T Saibara
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T Kaname
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K Yamamura
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S Onishi
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Y Shizuta
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Aromatase P450 (CYP19) is an enzyme catalysing the conversion of androgens into oestrogens. We generated mice lacking aromatase activity (ArKO) by targeted disruption of Cyp19 and report the characteristic features of the ArKO ovaries and uteri as revealed by histological and biochemical analyses. ArKO females were totally infertile but there were as many developing follicles in their ovaries at 8 weeks of age as in wild-type ovaries. Nevertheless, no typical corpus luteum was observed in the ArKO ovaries. Electron microscopy revealed the presence of well-developed smooth endoplasmic reticulum, few lipid droplets and mitochondria with less organized tubular structures in the ArKO luteinized interstitial cells. These ultrastructural features were different from those of the wild-type interstitial cells, where there are many lipid droplets and mitochondria with well-developed tubular structures, characteristic of steroid-producing cells. When ArKO mice were supplemented with 17beta-oestradiol (E(2); 15 microg/mouse) every fourth day from 4 weeks of age for 1 month, increased numbers of follicles were observed in the ovaries as compared with those of untreated ArKO mice, although no typical corpus luteum was detectable. Ultrastructural analysis revealed the disappearance of the accumulated smooth endoplasmic reticulum in the luteinized interstitial cells after E(2 )supplementation. Transcripts of pro-apoptotic genes such as p53 and Bax genes were markedly elevated in the ArKO ovaries as compared with those of wild-type mice. Although E(2) supplementation did not cause suppression of the elevated expression of p53 and Bax mRNAs, it caused marked enhancement of expression levels of lactoferrin and progesterone receptor mRNAs in the uteri as well as increases in uterine wet weight. At 8 months of age, ArKO mice developed haemorrhages in the ovaries, in which follicles were nearly depleted, while age-matched wild-type females still had many ovarian follicles. Furthermore, macrophage-like cells were occasionally observed in the ArKO ovarian follicles. These results suggested that targeted disruption of Cyp19 caused anovulation and precocious depletion of ovarian follicles. Additionally, analysis of mice supplemented with E(2) demonstrated that E(2) apparently supports development of ovarian follicles, although it did not restore the defect in ovulation.

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Anna Cinkajzlová Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
Institute of Medical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine and General University Hospital, Charles University, Prague, Czech Republic

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Miloš Mráz Institute of Medical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine and General University Hospital, Charles University, Prague, Czech Republic
Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic

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Martin Haluzík Institute of Medical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine and General University Hospital, Charles University, Prague, Czech Republic
Diabetes Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic

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both main lines – myeloid and lymphoid – can be found in AT, albeit with different frequency and significance for the development of AT inflammation with the most important being macrophages and T lymphocytes and their different phenotype subtypes

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Morag J Young Cardiovascular Endocrinology, Department of Physiology, MIMR-PHI Institute, 27–31 Wright St, Clayton 3168, Australia
Cardiovascular Endocrinology, Department of Physiology, MIMR-PHI Institute, 27–31 Wright St, Clayton 3168, Australia

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Amanda J Rickard Cardiovascular Endocrinology, Department of Physiology, MIMR-PHI Institute, 27–31 Wright St, Clayton 3168, Australia
Cardiovascular Endocrinology, Department of Physiology, MIMR-PHI Institute, 27–31 Wright St, Clayton 3168, Australia

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series of transgenic mouse models targeting the MR in the cardiovascular system have highlighted novel and distinct roles for MR signalling in vascular smooth muscle cells (VSMCs), endothelial cells, cardiomyocytes and monocytes/macrophages in cardiac

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Milos Mraz Third Department of Medicine – Department of Endocrinology and Metabolism, General University Hospital, First Faculty of Medicine of Charles University in Prague, U nemocnice 1, 128 00 Prague 2, Czech Republic

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Martin Haluzik Third Department of Medicine – Department of Endocrinology and Metabolism, General University Hospital, First Faculty of Medicine of Charles University in Prague, U nemocnice 1, 128 00 Prague 2, Czech Republic

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of a number of immunomodulatory molecules including cytokines and chemokines from tissue-resident macrophages and mast cells, provoking a rapid recruitment of neutrophils first and then macrophages and lymphocytes from circulation to the inflammation

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Xiaofeng Ding Department of Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
Key Laboratory of Protein Chemistry and Development Biology of State Education Ministry of China, College of Life Science, Hunan Normal University, Changsha, Hunan, China

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Yan Luo Department of Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
Department of Metabolism and Endocrinology, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China

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Xing Zhang Department of Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA

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Handong Zheng Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA

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Xin Yang Department of Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA

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Xuexian Yang Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA

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Meilian Liu Department of Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
Department of Metabolism and Endocrinology, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China

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adipose tissue-specific type 2 immune response is characterized by infiltration of eosinophils, group 2 innate lymphoid cells (ILC2s), IL4- and/or IL13-induced M2 macrophages; production of type 2 cytokines; and plays a critical role in regulating browning

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