Regulation of bone growth via ligand-specific activation of estrogen receptor alpha
Estrogens are well known for their capacity to promote bone maturation and at high doses to induce growth plate closure and thereby stop further growth. High-dose estrogen treatment has therefore been used to limit growth in extremely tall girls. However, recent data suggest that this treatment may have severe side effects, including increased risk of cancer and reduced fertility. We hypothesized that estrogenic effects in bone are mediated via ERα signaling. Twelve-week-old ovariectomized female C57BL/6 mice were subcutaneously injected for 4 weeks with E2 or selective ERα (PPT) or ERβ (DPN) agonists. Aft...
Source: Journal of Endocrinology - January 12, 2017 Category: Endocrinology Authors: Iravani, M., Lagerquist, M., Ohlsson, C., Savendahl, L. Tags: Research Source Type: research
Biologically active recombinant carp LH as a spawning-inducing agent for carp
Currently, spawning is induced in carp species by carp pituitary extract (CPE) and a combination of synthetic agonist of GnRH combined with a dopamine antagonist. The main goal of this study was the production of recombinant gonadotropins (GtHs) on a large scale to serve as an alternative to currently used agents. We produced carp (c) recombinant (r) Lh as a single chain in the methylotrophic yeast Pichia pastoris. Lha subunit was joined with Lhb subunit with a flexible linker of three glycine–serine repeats and six Histidines to form a mature protein, the β-subunit formed the N-terminal part and the α-sub...
Source: Journal of Endocrinology - January 12, 2017 Category: Endocrinology Authors: Aizen, J., Hollander-Cohen, L., Shpilman, M., Levavi-Sivan, B. Tags: Research Source Type: research
Growth hormone: a newly identified developmental organizer
The sexually dimorphic expression of cytochromes P450 (CYP) drug-metabolizing enzymes has been reported in all species examined. These sex differences are only expressed during adulthood and are solely regulated by sex differences in circulating growth hormone (GH) profiles. Once established, however, the different male- and female-dependent CYP isoform profiles are permanent and immutable, suggesting that adult CYP expression requires imprinting. As the hormone that regulates an adult function is likely the same hormone that imprints the function, we selectively blocked GH secretion in some newborn male rats, whereas othe...
Source: Journal of Endocrinology - January 12, 2017 Category: Endocrinology Authors: Das, R. K., Banerjee, S., Shapiro, B. H. Tags: Research Source Type: research
The role of nutrient sensing in the metabolic changes after gastric bypass surgery
In conclusion, RYGB surgery decreased body weight in both WT and α-gust–/– mice. Elevated plasma GLP1 and PYY levels might mediate this effect, although α-gustducin differentially affects several regulatory systems in the foregut and hindgut, tuning gut hormone release. (Source: Journal of Endocrinology)
Source: Journal of Endocrinology - January 12, 2017 Category: Endocrinology Authors: Steensels, S., Lannoo, M., Avau, B., Laermans, J., Vancleef, L., Farre, R., Verbeke, K., Depoortere, I. Tags: Research Source Type: research
Selyes general adaptation syndrome: stress-induced gastro-duodenal ulceration and inflammatory bowel disease
Hans Selye in a note to Nature in 1936 initiated the field of stress research by showing that rats exposed to nocuous stimuli responded by way of a ‘general adaptation syndrome’ (GAS). One of the main features of the GAS was the ‘formation of acute erosions in the digestive tract, particularly in the stomach, small intestine and appendix’. This provided experimental evidence for the view based on clinical data that gastro-duodenal (peptic) ulcers could be caused by stress. This hypothesis was challenged by Marshall and Warren’s Nobel Prize (2005)-winning discovery of a causal association betwe...
Source: Journal of Endocrinology - January 12, 2017 Category: Endocrinology Authors: Fink, G. Tags: Focused Review Source Type: research
Thyroid hormones induce browning of white fat
The canonical view about the effect of thyroid hormones (THs) on thermogenesis assumes that the hypothalamus acts merely as a modulator of the sympathetic outflow on brown adipose tissue (BAT). Recent data have challenged that vision by demonstrating that THs act on the ventromedial nucleus of the hypothalamus (VMH) to inhibit AMP-activated protein kinase (AMPK), which regulates the thermogenic program in BAT, leading to increased thermogenesis and weight loss. Current data have shown that in addition to activation of brown fat, the browning of white adipose tissue (WAT) might also be an important thermogenic mechanism. Ho...
Source: Journal of Endocrinology - January 9, 2017 Category: Endocrinology Authors: Martinez-Sanchez, N., Moreno-Navarrete, J. M., Contreras, C., Rial-Pensado, E., Ferno, J., Nogueiras, R., Dieguez, C., Fernandez-Real, J.-M., Lopez, M. Tags: Research Source Type: research
Dissecting thyroid hormone transport and metabolism in dendritic cells
We reported thyroid hormone (TH) receptor expression in murine dendritic cells (DCs) and 3,5,3'-triiodothyronine (T3)-dependent stimulation of DC maturation and ability to develop a Th1-type adaptive response. Moreover, an increased DC capacity to promote antigen-specific cytotoxic T-cell activity, exploited in a DC-based antitumor vaccination protocol, was revealed. However, putative effects of the main circulating TH, l-thyroxine (T4) and the mechanisms of TH transport and metabolism at DC level, crucial events for TH action at target cell level, were not known. Herein, we show that T4 did not reproduce those registered ...
Source: Journal of Endocrinology - January 5, 2017 Category: Endocrinology Authors: Gigena, N., Alamino, V. A., Montesinos, M. d. M., Nazar, M., Louzada, R. A., Wajner, S. M., Maia, A. L., Masini-Repiso, A. M., Carvalho, D. P., Cremaschi, G. A., Pellizas, C. G. Tags: Research Source Type: research
Absence of 11-keto reduction of cortisone and 11-ketotestosterone in the model organism zebrafish
Zebrafish are widely used as model organism. Their suitability for endocrine studies, drug screening and toxicity assessements depends on the extent of conservation of specific genes and biochemical pathways between zebrafish and human. Glucocorticoids consist of inactive 11-keto (cortisone and 11-dehydrocorticosterone) and active 11β-hydroxyl forms (cortisol and corticosterone). In mammals, two 11β-hydroxysteroid dehydrogenases (11β-HSD1 and 11β-HSD2) interconvert active and inactive glucocorticoids, allowing tissue-specific regulation of glucocorticoid action. Furthermore, 11β-HSDs are involved i...
Source: Journal of Endocrinology - January 3, 2017 Category: Endocrinology Authors: Tsachaki, M., Meyer, A., Weger, B., Kratschmar, D. V., Tokarz, J., Adamski, J., Belting, H.-G., Affolter, M., Dickmeis, T., Odermatt, A. Tags: Research Source Type: research
Gene expression signature: a powerful approach for drug discovery in diabetes
Type 2 diabetes (T2D) is increasing in prevalence at an alarming rate around the world. Much effort has gone into the discovery and design of antidiabetic drugs; however, those already available are unable to combat the underlying causes of the disease and instead only moderate the symptoms. The reason for this is that T2D is a complex disease, and attempts to target one biological pathway are insufficient to combat the full extent of the disease. Additionally, the underlying pathophysiology of this disease is yet to be fully elucidated making it difficult to design drugs that target the mechanisms involved. Therefore, the...
Source: Journal of Endocrinology - January 3, 2017 Category: Endocrinology Authors: Sithara, S., Crowley, T. M., Walder, K., Aston-Mourney, K. Tags: Review Source Type: research
Very low-density lipoprotein (VLDL)-induced signals mediating aldosterone production
Aldosterone, secreted by the adrenal zona glomerulosa, enhances sodium retention, thus increasing blood volume and pressure. Excessive production of aldosterone results in high blood pressure and contributes to cardiovascular and renal disease, stroke and visual loss. Hypertension is also associated with obesity, which is correlated with other serious health risks as well. Although weight gain is associated with increased blood pressure, the mechanism by which excess fat deposits increase blood pressure remains unclear. Several studies have suggested that aldosterone levels are elevated with obesity and may represent a lin...
Source: Journal of Endocrinology - January 3, 2017 Category: Endocrinology Authors: Tsai, Y.-Y., Rainey, W. E., Bollag, W. B. Tags: Review Source Type: research
Hormonal alterations in PCOS and its influence on bone metabolism
According to the World Health Organization (WHO) polycystic ovary syndrome (PCOS) occurs in 4–8% of women worldwide. The prevalence of PCOS in Indian adolescents is 12.2% according to the Indian Council of Medical Research (ICMR). The National Institute of Health has documented that it affects approximately 5 million women of reproductive age in the United States. Hormonal imbalance is the characteristic of many women with polycystic ovarian syndrome (PCOS). The influence of various endocrine changes in PCOS women and their relevance to bone remains to be documented. Hormones, which include gonadotrophin-releasing ho...
Source: Journal of Endocrinology - December 19, 2016 Category: Endocrinology Authors: Krishnan, A., Muthusami, S. Tags: Review Source Type: research
INF-{gamma} encoding plasmid administration triggers bone loss and disrupts bone marrow microenvironment
IFN- is a pleotropic cytokine produced in the bone microenvironment. Although IFN- is known to play a critical role on bone remodeling, its function is not fully elucidated. Consistently, outcomes on the effects of IFN- recombinant protein on bone loss are contradictory among reports. In our work we explored, for the first time, the role of IFN- encoding plasmid (pIFN-) in a mouse model of osteopenia induced by ovariectomy and in the sham-operated counterpart to estimate its effects in skeletal homeostasis. Ovariectomy produced a dramatic decrease of bone mineral density (BMD). pINF- injected mice showed a pathologic bone ...
Source: Journal of Endocrinology - December 18, 2016 Category: Endocrinology Authors: Agas, D., Gusmao Silva, G., Laus, F., Marchegiani, A., Capitani, M., Vullo, C., Catone, G., Lacava, G., Concetti, A., Marchetti, L., Sabbieti, M. G. Tags: Research Source Type: research
17{beta}-estradiol improves hepatic mitochondrial biogenesis and function through PGC1B
Sexual dimorphism in mitochondrial biogenesis and function has been described in many rat tissues, with females showing larger and more functional mitochondria. The family of the peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1) plays a central role in the regulatory network governing mitochondrial biogenesis and function, but little is known about the different contribution of hepatic PGC1A and PGC1B in these processes. The aim of this study was to elucidate the role of 17β-estradiol (E2) in mitochondrial biogenesis and function in liver and assess the contribution of both hepatic PGC1A and PGC1B ...
Source: Journal of Endocrinology - December 18, 2016 Category: Endocrinology Authors: Galmes-Pascual, B. M., Nadal-Casellas, A., Bauza-Thorbrugge, M., Sbert-Roig, M., Garcia-Palmer, F. J., Proenza, A. M., Gianotti, M., Llado, I. Tags: Research Source Type: research
Islet adaptations in fetal sheep persist following chronic exposure to high norepinephrine
In this study, we determined if the compensatory increase in insulin secretion after chronic elevation of NE is independent of hyperglycemia in sheep fetuses and whether it is persistent in conjunction with islet desensitization to NE. After an initial assessment of glucose-stimulated insulin secretion (GSIS) at 129 ± 1 days of gestation, fetuses were continuously infused for seven days with NE and maintained at euglycemia with a maternal insulin infusion. Fetal GSIS studies were performed again on days 8 and 12. Adrenergic sensitivity was determined in pancreatic islets collected at day 12. NE infusion increased (P...
Source: Journal of Endocrinology - December 18, 2016 Category: Endocrinology Authors: Chen, X., Kelly, A. C., Yates, D. T., Macko, A. R., Lynch, R. M., Limesand, S. W. Tags: Research Source Type: research
11{beta}-hydroxysteroid dehydrogenase-1 deficiency alters the gut microbiome response to Western diet
The enzyme 11β-hydroxysteroid dehydrogenase (11β-HSD) interconverts active glucocorticoids and their intrinsically inert 11-keto forms. The type 1 isozyme, 11β-HSD1, predominantly reactivates glucocorticoids in vivo and can also metabolise bile acids. 11β-HSD1-deficient mice show altered inflammatory responses and are protected against the adverse metabolic effects of a high-fat diet. However, the impact of 11β-HSD1 on the composition of the gut microbiome has not previously been investigated. We used high-throughput 16S rDNA amplicon sequencing to characterise the gut microbiome of 11β-HSD1-d...
Source: Journal of Endocrinology - December 18, 2016 Category: Endocrinology Authors: Johnson, J. S., Opiyo, M. N., Thomson, M., Gharbi, K., Seckl, J. R., Heger, A., Chapman, K. E. Tags: Research Source Type: research
