Serum- and glucocorticoid-induced protein kinase 1 (SGK1) is regulated by store-operated Ca2+ entry and mediates cytoprotection against necrotic cell death.

Serum and glucocorticoid-regulated kinase 1 (SGK1) encodes a phosphatidylinositol 3-kinase-dependent serine/threonine kinase that is rapidly induced in response to cellular stressors and is an important cell survival signal. Previous studies have suggested that an increase in cytoplasmic Ca(2+) concentration ([Ca(2+)]c) is required for increased SGK1 expression, but the subcellular source of Ca(2+) regulating SGK1 transcription remains uncertain. Activation of endoplasmic reticulum stress (ERS) with thapsigargin (TG) increased SGK1 mRNA and protein expression in MDA-MB-231 cells. Intracellular Ca(2+) imaging revealed that store-operated Ca(2+) entry played a prominent role in SGK1 induction by TG. Neither ERS nor release of Ca(2+) from the ER was sufficient to activate SGK1. Prolonged elevation of intracellular Ca(2+) levels, however, triggered cell death with a much greater proportion of the cells undergoing necrosis rather than apoptosis. A relative increase in the percentage of cells undergoing necrosis was observed in cells expressing a short hairpin RNA targeted to the SGK1 gene. Necrotic cell death evoked by cytoplasmic Ca(2+) overloading was associated with persistent hyperpolarization of the inner mitochondrial membrane and a modest increase in calpain activation, but did not involve detectable caspase 3 or caspase 7 activation. The effects of cytoplasmic Ca(2+) overloading on mitochondrial membrane potential were significantly reduced in cells expressing SGK1 compared with SGK1-depleted cells. Our findings indicate that store-operated Ca(2+) entry regulates SGK1 expression in epithelial cells and suggest that SGK1-dependent cytoprotective signaling involves effects on maintaining mitochondrial function.

Serum and glucocorticoid-regulated kinase 1 (SGK1) activation in breast cancer: requirement for mTORC1 activity associates with ER-alpha expression.

Mammalian target of rapamycin (mTOR) is an attractive target for cancer treatment. While rapamycin and its derivatives (e.g., everolimus) have been shown to inhibit mTOR signaling and cell proliferation in preclinical models of breast cancer, mTOR inhibition has demonstrated variable clinical efficacy with a trend toward better responses in estrogen receptor alpha positive (ERα+) compared to ERα negative (ERα-) tumors. Recently, serum- and glucocorticoid-regulated kinase 1 (SGK1) was identified as a substrate of mTOR kinase activity. Previous studies have alternatively suggested that either mTORC1 or mTORC2 is exclusively required for SGK1's Ser422 phosphorylation and activation in breast cancer cells. We investigated the effect of rapamycin on the growth of several ERα+ and ERα- breast cancer cell lines and examined differences in the phosphorylation of mTOR substrates (SGK1, p70S6K, and Akt) that might account for the differing sensitivity of these cell lines to rapamycin. We also examined which mTOR complex contributes to SGK1-Ser422 phosphorylation in ERα+ versus ERα- breast cell lines. We then assessed whether inhibiting SGK1 activity added to rapamycin-mediated cell growth inhibition by either using the SGK1 inhibitor GSK650394A or expressing an SGK1 shRNA. We observed sensitivity to rapamycin-mediated growth inhibition and inactivation of insulin-mediated SGK1-Ser422 phosphorylation in ERα+ MCF-7 and T47D cells, but not in ERα- MDA-MB-231 or MCF10A-Myc cells. In addition, either depleting SGK1 with shRNA or inhibiting SGK1 with GSK650394A preferentially sensitized MDA-MB-231 cells to rapamycin. Finally, we found that rapamycin-sensitive SGK1-Ser422 phosphorylation required ERα expression in MCF-7 derived cell lines. Therefore, targeting SGK1 activity may improve the efficacy of rapamycin and its analogs in the treatment of ERα- breast cancer.

How older adults are perceived is influenced by their reported exercise status.

Nelson (2002) proposed that ageism occurs as a result of the negative perceptions individuals have of older adults. This study examined whether information about an older person's exercise habits would influence such perceptions. Participants (N = 1,230) from 3 age categories (16-25, 26-55, and 56+ yr) read a description of a 65-year-old man or woman describing 1 of 7 exercise statuses. Participants rated their perceptions of 13 aspects of the target's personality. A 3-way (Target Exercise Status × Target Gender × Participant Age) MANOVA revealed significant main effects for target exercise status. Nonexercisers were perceived less positively than the control target and the exercising targets. The results suggest that there are self-presentational costs associated with being a nonexerciser at an older age, but few self-presentation benefits accrued to older adults who engage in regular exercise.

Seating type and cognitive performance after 3 hours travel by high-speed boat in sea states 2-3.

INTRODUCTION: Transit in high-speed marine craft subjects occupants to a rough ride as the boat impacts the waves. This induces high levels of physical stress, which may inhibit cognitive performance during military operations and life-saving activities. Land-based research suggests that suspension seats reduce vibration and, therefore, stress. We hypothesized that subjects using suspension seats would demonstrate better cognitive performance, lower perceptions of exertion, fatigue, and sleepiness, and lower salivary concentrations of cortisol than those using fixed seats. METHODS: Subjects, naval personnel, were divided into fixed (N = 6) and suspension seat (N = 6) groups. Subjects undertook forward and backward number recall and random number generation tests pre- and post-transit (3 h in sea states 2-3). Salivary cortisol concentrations were sampled pre- (1100 h) and post-transit (1700 h) and at the same times on a control day. Post-transit perceptions of exertion, fatigue, and sleepiness were measured subjectively. RESULTS: The suspension seat group demonstrated better performance post-transit than the fixed seat group for forward number recall and showed a significant pre- to post-transit improvement in backward number recall. The suspension seat group reported less fatigue and sleepiness. The suspension seat group had significantly higher salivary cortisol concentrations than the fixed seat group post-transit. Regression analyses found a quadratic correlation between delta cortisol concentrations and delta random number generation scores (R2 = 0.68). DISCUSSION: Results show that the use of suspension seats during transit in high-speed marine craft may be advantageous with regard to cognitive performance.

The effects of approach angle on penalty kicking accuracy and kick kinematics with recreational soccer players.

Kicking accuracy is an important component of successful penalty kicks, which may be influenced by the approach angle. The purpose of this study was to examine the effects of approach angle on kicking accuracy and three-dimensional kinematics of penalty kicks. Seven male amateur recreational soccer players aged (mean ± s) 26 ± 3 years, body mass 74.0 ± 6.8 kg, stature 1.74 ± 0.06 m, who were right foot dominant, kicked penalties at a 0.6 x 0.6 m target in a full size goal from their self-selected approach angle, 30°, 45° and 60° (direction of the kick was 0°). Kicking accuracy and three-dimensional kinematics were recorded. Results revealed that there was no significant difference in kicking accuracy (p = 0.27) or ball velocity (p = 0.59) between the approach angles. Pelvic rotation was significantly greater under the 45° and the 60° approach angles than during the self-selected approach angle (p < 0.05). Thigh abduction of the kicking leg at impact using the 60° approach angle was significantly greater than during the self- selected approach (p = 0.01) and the 30° approach (p = 0.04). It was concluded that altering an individual's self-selected approach angle at recreational level did not improve kicking accuracy or ball velocity, despite altering aspects of underlying technique. Key pointsPenalty kicking accuracy and ball velocity were not improved by altering recreational soccer players' natural approach angle.However, widening the approach angle produced greater pelvic rotation and thigh abduction.Wider approach angles increased the range of motion of the pelvis, opening up the hips before ball contact, creating a greater arc of movement during the backswing and the follow-through.Wider approach angles also led to an increase in thigh abduction at impact, enabling the kicking foot to be placed further under the ball, which may improve ball contact.

Metabolically Activated Adipose Tissue Macrophages Perform Detrimental and Beneficial Functions during Diet-Induced Obesity.

During obesity, adipose tissue macrophages (ATMs) adopt a metabolically activated (MMe) phenotype. However, the functions of MMe macrophages are poorly understood. Here, we combine proteomic and functional methods to demonstrate that, in addition to potentiating inflammation, MMe macrophages promote dead adipocyte clearance through lysosomal exocytosis. We identify NADPH oxidase 2 (NOX2) as a driver of the inflammatory and adipocyte-clearing properties of MMe macrophages and show that, compared to wild-type, Nox2-/- mice exhibit a time-dependent metabolic phenotype during diet-induced obesity. After 8 weeks of high-fat feeding, Nox2-/- mice exhibit attenuated ATM inflammation and mildly improved glucose tolerance. After 16 weeks of high-fat feeding, Nox2-/- mice develop severe insulin resistance, hepatosteatosis, and visceral lipoatrophy characterized by dead adipocyte accumulation and defective ATM lysosomal exocytosis, a phenotype reproduced in myeloid cell-specific Nox2-/- mice. Collectively, our findings suggest that MMe macrophages perform detrimental and beneficial functions whose contribution to metabolic phenotypes during obesity is determined by disease progression.

Measurement of PIP3 levels reveals an unexpected role for p110ß in early adaptive responses to p110α-specific inhibitors in luminal breast cancer.

BYL719, which selectively inhibits the alpha isoform of the phosphatidylinositol 3-kinase (PI3K) catalytic subunit (p110a), is currently in clinical trials for the treatment of solid tumors, especially luminal breast cancers with PIK3CA mutations and/or HER2 amplification. This study reveals that, even among these sensitive cancers, the initial efficacy of p110α inhibition is mitigated by rapid re-accumulation of the PI3K product PIP3 produced by the p110ß isoform. Importantly, the reactivation of PI3K mediated by p110ß does not invariably restore AKT phosphorylation, demonstrating the limitations of using phospho-AKT as a surrogate to measure PI3K activation. Consistently, we show that the addition of the p110ß inhibitor to BYL719 prevents the PIP3 rebound and induces greater antitumor efficacy in HER2-amplified and PIK3CA mutant cancers.

Patenting personalized medicines in the UK, Europe and USA.

In this review, we take a look at the patentability issues surrounding personalized medicine patent claims. We examine how the USA and European Patent Office have dealt with such patent claims, and then review the UK 'inherency' and 'selection' decisions to take a view as to how the UK courts will deal with personalized medicine patent claims in the future. We conclude that the UK courts will likely be willing to uphold patent protection for personalized medicines in the right circumstances.

Glucocorticoid receptor antagonism as a novel therapy for triple-negative breast cancer.

PURPOSE: Triple-negative breast cancer (TNBC) accounts for 10% to 20% of newly diagnosed invasive breast cancer. Finding effective targets for chemotherapy-resistant TNBC has proven difficult in part because of TNBC's molecular heterogeneity. We have previously reported that likely because of the antiapoptotic activity of glucocorticoid receptor (GR) in estrogen receptor (ER)-negative breast epithelial and cancer cells, high GR expression/activity in early-stage TNBC significantly correlates with chemotherapy resistance and increased recurrence. We hypothesized that pretreatment with mifepristone, a GR antagonist, would potentiate the efficacy of chemotherapy in GR+ TNBCs by inhibiting the antiapoptotic signaling pathways of GR and increasing the cytotoxic efficiency of chemotherapy. EXPERIMENTAL DESIGN: TNBC cell apoptosis was examined in the context of physiologic glucocorticoid concentrations, chemotherapy, and/or pharmacologic concentrations of mifepristone. We used high-throughput live microscopy with continuous recording to measure apoptotic cells stained with a fluorescent dye and Western blot analysis to detect caspase-3 and PARP cleavage. The effect of mifepristone on GR-mediated gene expression was also measured. TNBC xenograft studies were performed in female severe combined immunodeficient (SCID) mice and tumors were measured following treatment with vehicle, paclitaxel, or mifepristone/paclitaxel. RESULTS: We found that although mifepristone treatment alone had no significant effect on TNBC cell viability or clonogenicity in the absence of chemotherapy, the addition of mifepristone to dexamethasone/paclitaxel treatment significantly increased cytotoxicity and caspase-3/PARP cleavage. Mifepristone also antagonized GR-induced SGK1 and MKP1/DUSP1 gene expression while significantly augmenting paclitaxel-induced GR+ MDA-MB-231 xenograft tumor shrinkage in vivo. CONCLUSIONS: These results suggest that mifepristone pretreatment could be a useful strategy for increasing tumor cell apoptosis in chemotherapy-resistant GR+ TNBC.

Formation of a human ß-cell population within pancreatic islets is set early in life.

CONTEXT: Insulin resistance can be compensated by increased functional pancreatic ß-cell mass; otherwise, diabetes ensues. Such compensation depends not only on environmental and genetic factors but also on the baseline ß-cell mass from which the expansion originates. OBJECTIVE: Little is known about assembly of a baseline ß-cell mass in humans. Here, we examined formation of ß-cell populations relative to other pancreatic islet cell types and associated neurons throughout the normal human lifespan. DESIGN AND METHODS: Human pancreatic sections derived from normal cadavers aged 24 wk premature to 72 yr were examined by immunofluorescence. Insulin, glucagon, and somatostatin were used as markers for ß-, α-, and δ-cells, respectively. Cytokeratin-19 marked ductal cells, Ki67 cell proliferation, and Tuj1 (neuronal class III ß-tubulin) marked neurons. RESULTS: Most ß-cell neogenesis was observed preterm with a burst of ß-cell proliferation peaking within the first 2 yr of life. Thereafter, little indication of ß-cell growth was observed. Postnatal proliferation of α- and δ-cells was rarely seen, but a wave of ductal cell proliferation was found mostly associated with exocrine cell expansion. The ß-cell to α-cell ratio doubled neonatally, reflecting increased growth of ß-cells, but during childhood, there was a 7-fold change in the ß-cell to δ-cell ratio, reflecting an additional loss of δ-cells. A close association of neurons to pancreatic islets was noted developmentally and retained throughout adulthood. Negligible neuronal association to exocrine pancreas was observed. CONCLUSION: Human baseline ß-cell population and appropriate association with other islet cell types is established before 5 yr of age.

Effect of acute exercise on cognitive control required during an Eriksen flanker task.

This study aimed to determine how cognitive control, engaged in a task requiring selective inhibition, is affected by acute steady-state exercise. An adapted version of the Eriksen flanker task, involving three types of trials that varied according to their level of congruency (congruent trials, stimulus-incongruent trials, and response-incongruent trials) was performed during 2 periods of 20-min cycling at a carefully controlled intensity (50% of maximal aerobic power). The results indicated that moderate exercise improves reaction time (RT) performance on the Eriksen flanker task. This facilitating effect appeared to be neither dependent on the nature of the interference (stimulus level conflict vs. response level conflict) nor on the amount of cognitive control engaged in the task (congruent vs. incongruent trials). Distributional RT analyses did not highlight any sign of impairment in the efficiency of cognitive control.

Acute incremental exercise, performance of a central executive task, and sympathoadrenal system and hypothalamic-pituitary-adrenal axis activity.

The purposes of this study were to examine the effect of acute incremental exercise on the performance of a central executive task; the responses of the sympathoadrenal system (SAS) and hypothalamic-pituitary-adrenal axis (HPAA) during exercise, while simultaneously carrying out the central executive task; and the ability of Delta plasma concentrations of epinephrine, norepinephrine, adrenocorticotropin hormone (ACTH) and cortisol to predict Delta performance on the central executive task. Subjects undertook a flanker task at rest and during exercise at 50% and 80% maximum aerobic power (MAP). SAS and HPAA activity were measured pre- and post-treatment by plasma concentrations of catecholamines, and cortisol and ACTH, respectively. Reaction time (RT) and number of errors for congruent and incongruent trials on the flanker task showed significant main effects with performance at 80% MAP higher than in the other conditions. RT post-correct responses were significantly faster than RT post-error at rest and 50% MAP but not at 80%. Pre- and post-treatment catecholamines showed a main effect of exercise with a linear increase. Post-treatment ACTH concentrations at 80% MAP were significantly greater than in the other conditions. Delta epinephrine and ACTH combined were significant predictors of Delta RT and Delta norepinephrine was a significant predictor of Delta number of errors. It was concluded that exercise must be at a high intensity to affect performance on the flanker task. Both the SAS and HPAA appear to play a role in the exercise-cognition interaction.

Curmudgeon or golden-ager?: reported exercise participation influences the perception of older adults.

This study examined whether information about an older person's exercise habits influences the impressions formed of them by others. British participants (N = 360) from three age categories (16-25 years old, 26-55 years old, and 56+ years old) were asked to read a description of a 65-year-old man or woman described as either an exerciser, a nonexerciser, or a person with no exercise status information. Participants rated the target on 13 personality and 10 physical appearance dimensions. MANOVAs revealed significant main effects for target exercise status and participant age. Exercisers received more favorable ratings than either the nonexercisers or the controls on the majority (15/23) of the personality and physical appearance dimensions (p < 0.05). Participants aged over 56 tended to rate targets more favorably than the other two age categories but only on the physical appearance ratings. The results suggest that there are self-presentational benefits associated with being an exerciser at an older age.