Body fat mass and the proportion of very large adipocytes in pregnant women are associated with gestational insulin resistance.

Pregnancy is accompanied by fat gain and insulin resistance. Changes in adipose tissue morphology and function during pregnancy and factors contributing to gestational insulin resistance are incompletely known. We sought to characterize adipose tissue in trimesters 1 and 3 (T1/T3) in normal weight (NW) and obese pregnant women, and identify adipose tissue-related factors associated with gestational insulin resistance

Muscle Fiber Viability, a Novel Method for the Fast Detection of Ischemic Muscle Injury in Rats

Acute lower extremity ischemia is a limb- and life-threatening clinical problem. Rapid detection of the degree of injury is crucial, however at present there are no exact diagnostic tests available to achieve this purpose. Our goal was to examine a novel technique - which has the potential to accurately assess the degree of ischemic muscle injury within a short period of time - in a clinically relevant rodent model. Male Wistar rats were exposed to 4, 6, 8 and 9 hours of bilateral lower limb ischemia induced by the occlusion of the infrarenal aorta. Additional animals underwent 8 and 9 hours of ischemia followed by 2 hours of reperfusion to examine the effects of revascularization. Muscle samples were collected from the left anterior tibial muscle for viability assessment. The degree of muscle damage (muscle fiber viability) was assessed by morphometric evaluation of NADH-tetrazolium reductase reaction on frozen sections. Right hind limbs were perfusion-fixed with paraformaldehyde and glutaraldehyde for light and electron microscopic examinations. Muscle fiber viability decreased progressively over the time of ischemia, with significant differences found between the consecutive times. High correlation was detected between the length of ischemia and the values of muscle fiber viability. After reperfusion, viability showed significant reduction in the 8-hour-ischemia and 2-hour-reperfusion group compared to the 8-hour-ischemia-only group, and decreased further after 9 hours of ischemia and 2 hours of reperfusion. Light- and electron microscopic findings correlated strongly with the values of muscle fiber viability: lesser viability values represented higher degree of ultrastructural injury while similar viability results corresponded to similar morphological injury. Muscle fiber viability was capable of accurately determining the degree of muscle injury in our rat model. Our method might therefore be useful in clinical settings in the diagnostics of acute ischemic muscle injury

A randomized controlled trial on the effectiveness of strength training on clinical and muscle cellular outcomes in patients with prostate cancer during androgen deprivation therapy: rationale and design

Background Studies indicate that strength training has beneficial effects on clinical health outcomes in prostate cancer patients during androgen deprivation therapy. However, randomized controlled trials are needed to scientifically determine the effectiveness of strength training on the muscle cell level. Furthermore, close examination of the feasibility of a high-load strength training program is warranted. The Physical Exercise and Prostate Cancer (PEPC) trial is designed to determine the effectiveness of strength training on clinical and muscle cellular outcomes in non-metastatic prostate cancer patients after high-dose radiotherapy and during ongoing androgen deprivation therapy. Methods/design Patients receiving androgen deprivation therapy for 9-36 months combined with external high-dose radiotherapy for locally advanced prostate cancer are randomized to an exercise intervention group that receives a 16 week high-load strength training program or a control group that is encouraged to maintain their habitual activity level. In both arms, androgen deprivation therapy is continued until the end of the intervention period. Clinical outcomes are body composition (lean body mass, bone mineral density and fat mass) measured by Dual-energy X-ray Absorptiometry, serological outcomes, physical functioning (muscle strength and cardio-respiratory fitness) assessed with physical tests and psycho-social functioning (mental health, fatigue and health-related quality of life) assessed by questionnaires. Muscle cellular outcomes are a) muscle fiber size b) regulators of muscle fiber size (number of myonuclei per muscle fiber, number of satellite cells per muscle fiber, number of satellite cells and myonuclei positive for androgen receptors and proteins involved in muscle protein degradation and muscle hypertrophy) and c) regulators of muscle fiber function such as proteins involved in cellular stress and mitochondrial function. Muscle cellular outcomes are measured on muscle cross sections and muscle homogenate from muscle biopsies obtained from muscle vastus lateralis. Discussion The findings from the PEPC trial will provide new knowledge on the effects of high-load strength training on clinical and muscle cellular outcomes in prostate cancer patients during androgen deprivation therapy. Trial registration ClinicalTrials.gov: NCT0065822

Mass spectrometric profiling of lipids in intestinal tissue from rats fed cereals processed for medical conditions

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used for lipid profiling of intestine tissue sections from rats fed specially processed cereals and rats fed ordinary feed as a control. This cereal is known to increase the activity of antisecretory factor in plasma and the exact mechanism for the activation process at the cellular level is unclear. ToF-SIMS has been used to track food induced changes in lipid content in intestinal tissue sections to gain insight into the possible mechanisms involved. Data from 20 intestine sections belonging to four different rats from each group of control and specially processed cereals-fed rats were obtained using the stage scan macroraster with a lateral resolution of 5 lm. Data were subsequently subjected to orthogonal partial least squares discriminant analysis. The data clearly show that changes of certain lipids are induced by the specially processed cereal feed. Scores plots show a well-defined separation between the two groups. The corresponding loading plots reveal that the groups separate mainly due to changes of vitamin E, phosphocholine, and phosphosphingolipid fragments, and that for the c18:2 fatty acid. The observed changes in lipids might give insight into the working mechanisms of antisecretory factor in the body, and this has been successfully used to understand the working mechanism of specially processed cereal-induced antisecretory factor activation in intestine

Super-resolution 3D maps to study the antisecretory factor's effects on different GABAa receptor subunits in rat cerebellar granule cells in vitro

The Antisecretory Factor (AF) is an endogenous protein that inhibits intestinal hypersecretion and various inflammation disorders in vivo. AF has been detected in many mammalian tissues and plasma, but its mechanisms of action are essentially unknown. Previously, we studied the pharmacological action of the AF on GABAA receptors in cerebellar granule cells, comparing the electrophysiological response evoked by two-photon mediated release of caged GABA compounds before and after the administration of AF-16, a 16 amino acids long peptide obtained from the amino-terminal end of the AF protein. After the treatment with AF-16, we observed an increase in the GABAA receptor responses, particularly in those containing the α6 subunit. To figure out the interactions of AF with GABAA receptors in the same cellular model (cerebellar granule cells), we combined immunofluorescence subunits’ staining with confocal and super-resolution microscopy. In particular, we took advantage of an innovative imaging technique that combines stimulated emission depletion (STED) with fluorescence lifetime microscopy (FLIM) to collect super-resolution 3D maps of different subunits distributed on the neuron cell membrane. We explored different approaches to analyze super-resolution fluorescence images obtained by labeling α1 and α6 subunits before and after 1-hour incubation with AF-16. Comparing pre- and post-treatment maps, we found differences in how different subunit populations respond to AF treatment. We critically analyzed these new experimental findings with our previous electrophysiological data to widen the knowledge of the mechanisms of interaction between GABAA receptor subunits and AF protein