Endocrine Abstracts

IGF binding proteins (IGFBPs) are important biomarkers for diagnostics and treatment studies. In different physiological conditions IGFBPs are actively degraded by specific proteases. Due to the detection of intact and fragmented IGFBPs, ELISA or RIA techniques may generate biased IGFBP-data. We thus developed quantitative western ligand blotting for comprehensive monitoring of intact IGFBPs and IGFBP-profiles in biological fluids of vertebrates. The dynamic range for each IGF...

Transport of farm animals is considered as a key stress factor including multiple stressors as handling or fasting. In humans, compounds for the IGF-system are affected by acute or critical illness or stress. We have asked, if compounds from the IGF-system also may have biomarker potential in farm animals. A total of 80 pigs were transported for 2 h from a commercial finishing farm to the slaughterhouse. Blood samples from 40 pigs were taken before (basal levels) and after shi...

IGFBP-2 represents a multifunctional protein with effects on growth, reproductive development, aging, and metabolism. For the expression of these diverse effects in vivo, IGFBP-2 has a number of binding sites for IGFs, integrins, and proteoglycans. In order to assess the relative contributions of these binding sites to the multiple effects of IGFBP-2, we have developed transgenic mouse models overexpressing intact or mutant IGFBP-2. Here we discuss functions of the RG...

The myokine irisin is secreted after cleavage of the transmembrane protein Fibronectin type III domain-containing protein five and was shown to induce a thermogenic program in white adipose tissue. This cleavage can be induced by exercise, thus linking exercise with browning of adipose tissue. We investigated the response of Fndc5/irisin as well as its inducer Peroxisome proliferator-activated receptor gamma co-activator 1α (Ppargc1a) in mice long-term selected for high t...

In rats, we have previously demonstrated that consumption of low-carbohydrate/high-fat diets (LC–HFD) led to significant reductions in circulating IGF1. We further observed that rats fed an extreme, ketogenic, but comparably low protein LC–HFD (LC–HF-2) showed loss of bodyweight, which was mainly due to loss of lean body mass (LBM). Consumption of a moderate protein LC–HF diet (LC–HF-1) did not affect LBM acquisition compared to controls. We now invest...

Maintenance of ketosis and increases in resting energy expenditure (EE) are two proposed mechanisms for weight loss observed in humans performing low-carbohydrate/high-fat (LC-HF) diets like the Atkin’s diet. To explore these potential mechanisms, we pair-fed isocaloric amounts of regular chow (CH) or two LC-HF diets (carbohydrates~1%ME) to male Wistar rats for 4 weeks. LC-HF-1 (fat~66%ME) was matched in protein content to CH, whereas LC-HF-2 was even higher in fat (~94%M...

Selenium (Se) is an essential trace element needed for the biosynthesis of selenoproteins. Biosynthesis of such proteins depends on the selenocysteine incorporation sequence binding protein 2 (SBP2), which represents a key trans-acting factor during the translation process. We recently described children with mutations in SBP2 gene who displayed an abnormal thyroid function test(s) and reduced selenoprotein concentrations. Now we aimed to improve selenoprotein biosynthesis and...