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The implementation of personalised learning in teaching English has become one of the effective approaches to cater learners’ needs in education. The educators in Malaysia, as in many countries, are interested in exploring the implementation of personalised learning in their lessons. However, the study on personalised learning to teach English in Malaysian schools is scarce. The prevalence of low academic achievement, especially in rural and low-enrolment schools, has led to teacher reluctance to adopt personalised learning approaches, potentially denying students the vital benefits of tailored education essential for their future success and development. Hence, this study aims to explore the implementation of personalised learning to teach English, particularly in Malaysian lowenrolment schools, as well as the challenges and ways to overcome the challenges. Personalised learning is implemented based on the SelfDetermination Theory in this study. This qualitative research used a narrative approach via oral history. Purposive and convenience sampling were used to select a total of four participants for this study. Online semistructured interviews were conducted with the participants to collect the data. The result analysis was trifold, including data transcription, data coding and data analysis to explore the research questions. Findings show that the implications of personalised learning in low-enrolment schools, grounded in the principles of Self-Determination Theory, are vast and promising. Personalised learning in English language education has the potential to transform Malaysia’s educational landscape by nurturing intrinsic motivation, enhancing language skills, engaging students culturally, supporting teacher development, and fostering systemic changes, ultimately improving academic achievement, engagement, and well-being.

The J-PARC Hadron Experimental Facility was constructed with an aim to explore the origin and evolution of matter in the universe through experiments with intense particle beams. In the past decade, many results from particle and nuclear physics experiments have been obtained at the present facility. To expand the physics programs to as yet unexplored regions, the extension project of the Hadron Experimental Facility has been extensively discussed. This contribution presents the physics of the extension of the Hadron Experimental Facility to resolve issues related to strangeness nuclear physics, hadron physics, and flavor physics.

Abstract In this study, we synthesized an organic electrochemical transistor (OECT) using dielectrophoresis of a carbon nanotube-Nafion (CNT-Nafion) suspension. Dielectrophoretically aligned nanowires formed a one-dimensional submicron bundle between triangular electrodes. The CNT-Nafion composite nanowire bundles showed p-type semiconductor characteristics. The drain-source current decreased with increasing gate voltage. The nanowire bundles showed potential as pH sensor because the drain-source current ratio varied linearly according to the gate voltage in pH buffers.

Abstract Carbon nanotube (CNT) is an attractive material for needle-like conducting electrodes because it has high electrical conductivity and mechanical strength. However, CNTs cannot provide the desired properties in certain applications. To obtain micro- and nanoneedles having the desired properties, it is necessary to fabricate functional needles using various other materials. In this study, functional micro- and nanoneedle electrodes were fabricated using a tungsten tip and an atomic force microscope probe with a CNT needle template and electrodeposition. To prepare the conductive needle templates, a single-wall nanotube nanoneedle was attached onto the conductive tip using dielectrophoresis and surface tension. Through electrodeposition, Au, Ni, and polypyrrole were each coated successfully onto CNT nanoneedle electrodes to obtain the desired properties.

Abstract Background From 1968 to 2002, Singapore experienced an almost four-fold increase in prostate cancer incidence. This paper examines the incidence, mortality and survival patterns for prostate cancer among all residents in Singapore from 1968 to 2002. Methods This is a retrospective population-based cohort study including all prostate cancer cases aged over 20 (n = 3613) reported to the Singapore Cancer Registry from 1968 to 2002. Age-standardized incidence, mortality rates and 5-year Relative Survival Ratios (RSRs) were obtained for each 5-year period. Follow-up was ascertained by matching with the National Death Register until 2002. A weighted linear regression was performed on the log-transformed age-standardized incidence and mortality rates over period. Results The percentage increase in the age-standardized incidence rate per year was 5.0%, 5.6%, 4.0% and 1.9% for all residents, Chinese, Malays and Indians respectively. The percentage increase in age-standardized mortality rate per year was 5.7%, 6.0%, 6.6% and 2.5% for all residents, Chinese, Malays and Indians respectively. When all Singapore residents were considered, the RSRs for prostate cancer were fairly constant across the study period with slight improvement from 1995 onwards among the Chinese. Conclusion Ethnic differences in prostate cancer incidence, mortality and survival patterns were observed. There has been a substantial improvement in RSRs since the 1990s for the Chinese.

Abstract Background Molecular genetic maps provide a means to link heritable traits with underlying genome sequence variation. Several genetic maps have been constructed for Brassica species, yet to date, there has been no simple means to compare this information or to associate mapped traits with the genome sequence of the related model plant, Arabidopsis. Description We have developed a comparative genetic map database for the viewing, comparison and analysis of Brassica and Arabidopsis genetic, physical and trait map information. This web-based tool allows users to view and compare genetic and physical maps, search for traits and markers, and compare genetic linkage groups within and between the amphidiploid and diploid Brassica genomes. The inclusion of Arabidopsis data enables comparison between Brassica maps that share no common markers. Analysis of conserved syntenic blocks between Arabidopsis and collated Brassica genetic maps validates the application of this system. This tool is freely available over the internet on http://bioinformatics.pbcbasc.latrobe.edu.au/cmap. Conclusion This database enables users to interrogate the relationship between Brassica genetic maps and the sequenced genome of A. thaliana, permitting the comparison of genetic linkage groups and mapped traits and the rapid identification of candidate genes.

Glucagon-like peptide 1 (GLP-1) is a gut-derived peptide secreted from intestinal L-cells after a meal. GLP-1 has numerous physiological actions, including potentiation of glucose-stimulated insulin secretion, enhancement of beta-cell growth and survival, and inhibition of glucagon release, gastric emptying, and food intake. These antidiabetic effects of GLP-1 have led to intense interest in the use of this peptide for the treatment of patients with type 2 diabetes. Oral nutrients such as glucose and fat are potent physiological regulators of GLP-1 secretion, but non-nutrient stimulators of GLP-1 release have also been identified, including the neuromodulators acetylcholine and gastrin-releasing peptide. Peripheral hormones that participate in energy homeostasis, such as leptin, have also been implicated in the regulation of GLP-1 release. Recent studies have begun to elucidate the intracellular signaling pathways that mediate the effects of GLP-1 secretagogues on the intestinal L-cell. The purpose of this review is to summarize the known signaling mechanisms of GLP-1 secretagogues based on the available literature. A better understanding of the pathways underlying GLP-1 secretion may lead to novel approaches by which the levels of this important insulinotropic hormone can be enhanced in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

The scaffold protein 14-3-3ζ is an established regulator of adipogenesis and postnatal adiposity. We and others have demonstrated the 14-3-3ζ interactome to be diverse and dynamic, and it can be examined to identify novel regulators of physiological processes, including adipogenesis. In the present study, we sought to determine if factors that influence adipogenesis during the development of obesity could be identified in the 14-3-3ζ interactome found in white adipose tissue of lean or obese TAP-tagged-14-3-3ζ overexpressing mice. Using mass spectrometry, differences in the abundance of novel, as well as established, adipogenic factors within the 14-3-3ζ interactome could be detected in adipose tissues. One novel candidate was revealed to be plakoglobin, the homolog of the known adipogenic inhibitor, β-catenin, and herein, we report that plakoglobin is involved in adipocyte differentiation. Plakoglobin is expressed in murine 3T3-L1 cells and is primarily localized to the nucleus, where its abundance decreases during adipogenesis. Depletion of plakoglobin by siRNA inhibited adipogenesis and reduced PPARγ2 expression, and similarly, plakoglobin depletion in human adipose-derived stem cells also impaired adipogenesis and reduced lipid accumulation post-differentiation. Transcriptional assays indicated that plakoglobin does not participate in Wnt/β-catenin signaling, as its depletion did not affect Wnt3a-mediated transcriptional activity. Taken together, our results establish plakoglobin as a novel regulator of adipogenesis in vitro and highlights the ability of using the 14-3-3ζ interactome to identify potential pro-obesogenic factors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Since their discovery nearly five decades ago, molecular scaffolds belonging to the 14-3-3 protein family have been recognized as pleiotropic regulators of diverse cellular and physiological functions. With their ability to bind to proteins harboring specific serine and threonine phosphorylation motifs, 14-3-3 proteins can interact with and influence the function of docking proteins, enzymes, transcription factors, and transporters that have essential roles in metabolism and glucose homeostasis. Here, we will discuss the regulatory functions of 14-3-3 proteins that will be of great interest to the fields of metabolism, pancreatic β-cell biology, and diabetes. We first describe how 14-3-3 proteins play a central role in glucose and lipid homeostasis by modulating key pathways of glucose uptake, glycolysis, oxidative phosphorylation, and adipogenesis. This is followed by a discussion of the contributions of 14-3-3 proteins to calcium-dependent exocytosis and how this relates to insulin secretion from β-cells. As 14-3-3 proteins are major modulators of apoptosis and cell cycle progression, we will explore if 14-3-3 proteins represent a viable target for promoting β-cell regeneration and discuss the feasibility of targeting 14-3-3 proteins to treat metabolic diseases such as diabetes., Article Highlights: 14-3-3 proteins are ubiquitously expressed scaffolds with multiple roles in glucose homeostasis and metabolism. 14-3-3ζ regulates adipogenesis via distinct mechanisms and is required for postnatal adiposity and adipocyte function. 14-3-3ζ controls glucose-stimulated insulin secretion from pancreatic β-cells by regulating mitochondrial function and ATP synthesis as well as facilitating cross talk between β-cells and α-cells., (© 2023 by the American Diabetes Association.)

We identify biomarkers for disease progression in three type 2 diabetes cohorts encompassing 2,973 individuals across three molecular classes, metabolites, lipids and proteins. Homocitrulline, isoleucine and 2-aminoadipic acid, eight triacylglycerol species, and lowered sphingomyelin 42:2;2 levels are predictive of faster progression towards insulin requirement. Of ~1,300 proteins examined in two cohorts, levels of GDF15/MIC-1, IL-18Ra, CRELD1, NogoR, FAS, and ENPP7 are associated with faster progression, whilst SMAC/DIABLO, SPOCK1 and HEMK2 predict lower progression rates. In an external replication, proteins and lipids are associated with diabetes incidence and prevalence. NogoR/RTN4R injection improved glucose tolerance in high fat-fed male mice but impaired it in male db/db mice. High NogoR levels led to islet cell apoptosis, and IL-18R antagonised inflammatory IL-18 signalling towards nuclear factor kappa-B in vitro. This comprehensive, multi-disciplinary approach thus identifies biomarkers with potential prognostic utility, provides evidence for possible disease mechanisms, and identifies potential therapeutic avenues to slow diabetes progression., (© 2023. The Author(s).)

Background & Aims: Fibrosis is a key determinant of clinical outcomes in nonalcoholic fatty liver disease (NAFLD), but time-dependent risk of mortality has not been reported in previous meta-analyses. We performed an updated time-to-event meta-analysis to provide robust estimates for all-cause and liver-related mortality in biopsy-confirmed NAFLD with comparisons between fibrosis stages., Methods: Medline and Embase databases were searched to include cohort studies reporting survival outcomes by fibrosis stage in biopsy-proven NAFLD. Survival estimates were pooled using reconstructed individual participant data. Conventional meta-analysis was conducted to pool adjusted hazard ratios (HRs) using DerSimonian and Laird random effects model., Results: A total of 14 articles involving 17,301 patients with NAFLD were included. All-cause mortality at 1, 5, and 10 years for stage 0 to 2 fibrosis was 0.1%, 3.3%, and 7.7% vs 0.3%, 20.6%, and 41.5% for stage 4 fibrosis. Compared with stage 0 fibrosis, all-cause mortality increased with fibrosis stage: stage 2; HR, 1.46 (95% confidence interval [CI], 1.08-1.98), stage 3; HR, 1.96 (95% CI, 1.41-2.72), and stage 4; HR, 3.66 (95% CI, 2.65-5.05). Risk for liver-related mortality increased exponentially as fibrosis stage increased: stage 2; HR, 4.07 (95% CI, 1.44-11.5), stage 3; HR, 7.59 (95% CI, 2.80-20.5), and stage 4; HR, 15.1 (95% CI, 5.27-43.4). Stage 3 to 4 fibrosis had a higher all-cause (HR, 3.32) and liver-related mortality (HR, 10.40) compared with stage 0 to 2 fibrosis, whereas stage 4 fibrosis had higher all-cause (HR, 2.67; 95% CI, 1.47-4.83) and liver-related mortality (HR, 2.57; 95% CI, 1.22-5.42) vs stage 3 fibrosis., Conclusions: Risk of all-cause and liver-related mortality increases substantially with fibrosis stage. These data have important implications for prognostication and trial design., (Copyright © 2023 AGA Institute. Published by Elsevier Inc. All rights reserved.)

During the past decades, unprecedented progress in technologies has revolutionized traditional research methodologies. Among these, advances in high-throughput drug screening approaches have permitted the rapid identification of potential therapeutic agents from drug libraries that contain thousands or millions of molecules. Moreover, high-throughput-based therapeutic target discovery strategies can comprehensively interrogate relationships between biomolecules (e.g., gene, RNA, and protein) and diseases and significantly increase the authors' knowledge of disease mechanisms. Diabetes is a chronic disease primarily characterized by the incapacity of the body to maintain normoglycemia. The prevalence of diabetes in modern society has become a severe public health issue that threatens the well-being of millions of patients. Although a number of pharmacological treatments are available, there is no permanent cure for diabetes, and discovering novel therapeutic targets and agents continues to be an urgent need. The present review discusses the technical details of high-throughput screening approaches in drug discovery, followed by introducing the applications of such approaches to diabetes research. This review aims to provide an example of the applicability of high-throughput technologies in facilitating different aspects of disease research., (© 2022 Wiley-VCH GmbH.)

While critical for neurotransmitter synthesis, 14-3-3 proteins are often assumed to have redundant functions due to their ubiquitous expression, but despite this assumption, various 14-3-3 isoforms have been implicated in regulating metabolism. We previously reported contributions of 14-3-3ζ in β cell function, but these studies were performed in tumor-derived MIN6 cells and systemic KO mice. To further characterize the regulatory roles of 14-3-3ζ in β cell function, we generated β cell-specific 14-3-3ζ-KO mice. Although no effects on β cell mass were detected, potentiated glucose-stimulated insulin secretion (GSIS), mitochondrial function, and ATP synthesis were observed. Deletion of 14-3-3ζ also altered the β cell transcriptome, as genes associated with mitochondrial respiration and oxidative phosphorylation were upregulated. Acute 14-3-3 protein inhibition in mouse and human islets recapitulated the enhancements in GSIS and mitochondrial function, suggesting that 14-3-3ζ is the critical isoform in β cells. In dysfunctional db/db islets and human islets from type 2 diabetic donors, expression of Ywhaz/YWHAZ, the gene encoding 14-3-3ζ, was inversely associated with insulin secretion, and pan-14-3-3 protein inhibition led to enhanced GSIS and mitochondrial function. Taken together, this study demonstrates important regulatory functions of 14-3-3ζ in the regulation of β cell function and provides a deeper understanding of how insulin secretion is controlled in β cells.

The canonical Wnt signaling pathway is ubiquitous throughout the body and influences a diverse array of physiological processes. Following the initial discovery of the Wnt signaling pathway during wing development in Drosophila melanogaster , it is now widely appreciated that active Wnt signaling in mammals is necessary for the development and growth of various tissues involved in whole-body metabolism, such as brain, liver, pancreas, muscle, and adipose. Moreover, elegant gain- and loss-of-function studies have dissected the tissue-specific roles of various downstream effector molecules in the regulation of energy homeostasis. This review attempts to highlight and summarize the contributions of the Wnt signaling pathway and its downstream effectors on whole-body metabolism and their influence on the development of metabolic diseases, such as diabetes and obesity. A better understanding of the Wnt signaling pathway in these tissues may aid in guiding the development of future therapeutics to treat metabolic diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Abou Azar and Lim.)

The extracellular matrix (ECM) is important for normal development and disease states, including inflammation and fibrosis. To understand the complex regulation of ECM, we performed a suppressor screening using Caenorhabditis elegans expressing the mutant ROL-6 collagen protein. One cuticle mutant has a mutation in dpy-23 that encodes the μ2 adaptin (AP2M1) of clathrin-associated protein complex II (AP-2). The subsequent suppressor screening for dpy-23 revealed the lon-2 mutation. LON-2 functions to regulate body size through negative regulation of the tumor growth factor-beta (TGF-β) signaling pathway responsible for ECM production. RNA-seq analysis showed a dominant change in the expression of collagen genes and cuticle components. We noted an increase in the cav-1 gene encoding caveolin-1, which functions in clathrin-independent endocytosis. By knockdown of cav-1 , the reduced TGF-β signal was significantly restored in the dpy-23 mutant. In conclusion, the dpy-23 mutation upregulated cav-1 expression in the hypodermis, and increased CAV-1 resulted in a decrease of TβRI. Finally, the reduction of collagen expression including rol-6 by the reduced TGF-β signal influenced the cuticle formation of the dpy-23 mutant. These findings could help us to understand the complex process of ECM regulation in organism development and disease conditions.

Metastasis is the main cause of cancer-related deaths. Anoikis is a type of apoptosis caused by cell detachment, and cancer cells become anoikis resistant such that they survive during circulation and can successfully metastasize. Therefore, sensitization of cancer cells to anoikis could prevent metastasis. Here, by screening for anoikis sensitizer using natural compounds, we found that pygenic acid A (PA), a natural compound from Prunella vulgaris , not only induced apoptosis but also sensitized the metastatic triple-negative breast cancer cell lines, MDA-MB-231 cells (human) and 4T1 cells (mouse), to anoikis. Apoptosis protein array and immunoblotting analysis revealed that PA downregulated the pro-survival proteins, including cIAP1, cIAP2, and survivin, leading to cell death of both attached and suspended cells. Interestingly, PA decreased the levels of proteins associated with anoikis resistance, including p21, cyclin D1, p-STAT3, and HO-1. Ectopic expression of active STAT3 attenuated PA-induced anoikis sensitivity. Although PA activated ER stress and autophagy, as determined by increases in the levels of characteristic markers, such as IRE1α, p-elF2α, LC3B I, and LC3B II, PA treatment resulted in p62 accumulation, which could be due to PA-induced defects in autophagy flux. PA also decreased metastatic characteristics, such as cell invasion, migration, wound closure, and 3D growth. Finally, lung metastasis of luciferase-labeled 4T1 cells decreased following PA treatment in a syngeneic mouse model when compared with the control. These data suggest that PA sensitizes metastatic breast cancer cells to anoikis via multiple pathways, such as inhibition of pro-survival pathways and activation of ER stress and autophagy, leading to the inhibition of metastasis. These findings suggest that sensitization to anoikis by PA could be used as a new therapeutic strategy to control the metastasis of breast cancer.

Objective: Adaptive thermogenesis, which is partly mediated by sympathetic input on brown adipose tissue (BAT), is a mechanism of heat production that confers protection against prolonged cold exposure. Various endogenous stimuli, for example, norepinephrine and FGF-21, can also promote the conversion of inguinal white adipocytes to beige adipocytes, which may represent a secondary cell type that contributes to adaptive thermogenesis. We previously identified an essential role of the molecular scaffold 14-3-3ζ in adipogenesis, but one of the earliest, identified functions of 14-3-3ζ is its regulatory effects on the activity of tyrosine hydroxylase, the rate-limiting enzyme in the synthesis of norepinephrine. Herein, we examined whether 14-3-3ζ could influence adaptive thermogenesis via actions on BAT activation or the beiging of white adipocytes., Methods: Transgenic mice over-expressing a TAP-tagged human 14-3-3ζ molecule or heterozygous mice without one allele of Ywhaz, the gene encoding 14-3-3ζ, were used to explore the contribution of 14-3-3ζ to acute (3 h) and prolonged (3 days) cold (4 °C) exposure. Metabolic caging experiments, PET-CT imaging, and laser Doppler imaging were used to determine the effect of 14-3-3ζ over-expression on thermogenic and vasoconstrictive mechanisms in response to cold., Results: Transgenic over-expression of 14-3-3ζ (TAP) in male mice significantly improved tolerance to acute and prolonged cold. In response to cold, body temperatures in TAP mice did not decrease to the same extent when compared to wildtype (WT) mice, and this was associated with increased UCP1 expression in beige inguinal white tissue (iWAT) and BAT. Of note was the paradoxical finding that cold-induced changes in body temperatures of TAP mice were associated with significantly decreased energy expenditure. The marked improvements in tolerance to prolonged cold were not due to changes in sensitivity to β-adrenergic stimulation or BAT or iWAT oxidative metabolism; instead, over-expression of 14-3-3ζ significantly decreased thermal conductance and heat loss in mice via increased peripheral vasoconstriction., Conclusions: Despite being associated with elevations in cold-induced UCP1 expression in brown or beige adipocytes, these findings suggest that 14-3-3ζ regulates an alternative, non-thermogenic mechanism via vasoconstriction to minimize heat loss during cold exposure., (Copyright © 2020 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

The purpose of this study was to analyze the relationship between the height and depth of buccal non-carious cervical lesions (NCCLs) and the relationship between the size of buccal NCCLs and clinical crown-root ratio of both buccal and lingual (palatal) sides using micro-computed tomography (micro-CT) images of the teeth and periodontal tissues from the cadavers. The micro-CT images of 56 teeth and their supporting tissues were obtained from 17 cadavers. From these images, the height and depth of NCCLs and the length of the buccal and lingual (palatal) clinical crowns were measured, and the conventional/modified clinical crown-root ratios were calculated. The height and depth ratio of NCCLs were analyzed statistically with the conventional/modified crown-root ratios by Pearson's correlation and multiple regression. According to the Pearson's correlation, the height and depth of buccal NCCLs were positively correlated with the modified buccal clinical crown-root ratio (p < 0.001 and p = 0.013, respectively). The regression model composed of variables of crown-root ratios explained the height of buccal NCCLs, and the prominent factor of the model was the modified buccal clinical crown-root ratio (p < 0.001). Moreover, the depth of buccal NCCLs was also explained by the regression model, and its prominent factor was the proportion of modified buccal and lingual (palatal) clinical crowns (p = 0.004). The buccal NCCLs were related to the crown-root ratios; particularly, the level of buccal gingival margin could be associated with the formation of buccal NCCLs., Competing Interests: NO authors have competing interests.

Hyperinsulinemia plays a causal role in adipose tissue expansion. Mice with reduced insulin have increased energy expenditure, but the mechanisms remained unclear. Here we investigated the effects of genetically reducing insulin production on uncoupling and oxidative mitochondrial proteins in liver, skeletal muscle, white adipose tissue (WAT), and brown adipose tissue (BAT). Male Ins1 +/+ or Ins1 +/- littermates were fed either a low-fat diet (LFD) or a high-fat diet (HFD) for 4 wk, starting at 8 wk of age. Replicating our previous observations, HFD increased fasting hyperinsulinemia, and Ins1 +/- mice had significantly lower circulating insulin compared with Ins1 +/+ littermates. Fasting glucose and body weight were not different between genotypes. We did not observe robust significant differences in liver or skeletal muscle. In mesenteric WAT, Ins1 +/- mice had reduced Ndufb8 and Sdhb, while Ucp1 was increased in the context of HFD. HFD alone had a dramatic inhibitory effect on Pparg abundance. In inguinal WAT, Ins1 +/- mice exhibited significant increases in oxidative complex proteins, independent of diet, without affecting Ucp1, Pparg, or Prdm16:Pparg association. In BAT, lowered insulin increased Sdhb protein levels that had been reduced by HFD. Ucp1 protein, Prdm16:Pparg association, and Sirt3 abundance were all increased in the absence of diet-induced hyperinsulinemia. Our data show that reducing insulin upregulates oxidative proteins in inguinal WAT without affecting Ucp1, whereas in mesenteric WAT and BAT, reducing insulin upregulates Ucp1 in the context of HFD. Preventing hyperinsulinemia has early depot-specific effects on adipose tissue metabolism and helps explain the increased energy expenditure previously reported in Ins1 +/- mice.

Skin aging is influenced by several genetic, physiological, and environmental factors. In particular, ultraviolet (UV) exposure is an important factor involved in inducing skin photoaging. Autophagy controlling homeostatic balance between the synthesis, degradation, and recycling of cellular organelles and proteins plays important regulatory roles in several biological processes, including aging. The opioid neuropeptide α-neoendorphin (named NEP) is an endogenous decapeptide (N-YGGFLRKYPK-C) that activates the kappa opioid receptor and exhibits certain anti-aging and anti-wrinkling effects on skin cells; however, its action mechanism has not yet been elucidated. Therefore, the aim of this study was to determine the effects of NEP on anti-skin aging and autophagy activation in human dermal fibroblast cells. Western blot results showed that NEP down-regulates the production of phospho-mammalian target of rapamycin (p-mTOR), whereas increases the expression of key autophagy-related molecules such as Beclin-1, Atg5-Atg12, and LC3-II. The immunocytochemical analysis performed with anti-LC3-II antibody also showed that the autophagic indicators, autophagosomes are formed by NEP. These results suggest that NEP can activate cellular autophagy through mTOR-Beclin-1-mediated signaling pathway. It was also revealed by CM-H 2 DCF-DA assay and Western blottings that NEP can reduce the production of ultraviolet B (UVB)-induced reactive oxygen species (ROS) like with N-acetylcysteine (NAC), resulting in decreasing the expression levels of skin aging-related proteins, such as phospho-ERK (p-ERK), phospho-p38 (p-p38), and phospho-JNK (p-JNK). Furthermore, NEP could increase the type I procollagen production, while decreasing MMP-1, MMP-2, and MMP-9 activities. Taken together, the results demonstrate that NEP can reduce UVB-induced photoaging by activating autophagy., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

One of the primary metabolic functions of a mature adipocyte is to supply energy via lipolysis, or the catabolism of stored lipids. Adipose triacylglycerol lipase (ATGL) and hormone-sensitive lipase (HSL) are critical lipolytic enzymes, and their phosphorylation generates phospho-binding sites for 14-3-3 proteins, a ubiquitously expressed family of molecular scaffolds. Although we previously identified essential roles of the 14-3-3ζ isoform in murine adipogenesis, the presence of 14-3-3 protein binding sites on ATGL and HSL suggests that 14-3-3ζ could also influence mature adipocyte processes like lipolysis. Here we demonstrate that 14-3-3ζ is necessary for lipolysis in male mice and fully differentiated 3T3-L1 adipocytes, as depletion of 14-3-3ζ significantly impaired glycerol and free fatty acid (FFA) release. Unexpectedly, reducing 14-3-3ζ expression was found to significantly impact adipocyte maturity, as observed by reduced abundance of peroxisome proliferator-activated receptor (PPAR)γ2 protein and expression of mature adipocyte genes and those associated with de novo triglyceride synthesis and lipolysis. The impact of 14-3-3ζ depletion on adipocyte maturity was further examined with untargeted lipidomics, which revealed that reductions in 14-3-3ζ abundance promoted the acquisition of a lipidomic signature that resembled undifferentiated preadipocytes. Collectively, these findings reveal a novel aspect of 14-3-3ζ in adipocytes, as reducing 14-3-3ζ was found to have a negative effect on adipocyte maturity and adipocyte-specific processes like lipolysis.

Background: Intraperitoneal isotonic saline instillation (SI) and pulmonary recruitment maneuver (RM) were indicated to alleviate post-laparoscopic shoulder pain (PLSP) effectively. The aim of this study was to compare the effects of the single strategy using SI alone and the combined strategy using SI and RM on PLSP reduction., Methods: Subjects undergoing elective gynecologic laparoscopy were randomly allocated to a control group (no intervention, n = 48) and two intervention groups (single strategy of SI alone, n = 48; combined strategy of SI and RM, n = 48). In the control group, carbon dioxide was removed only via passive evacuation through the port sites at the completion of the laparoscopic procedure. In the saline instillation group, 20-mL/kg of body weight SI was performed. In the combined strategy group, RM using five pulmonary inflations was performed, in addition to SI. The PLSP scores, which were the primary outcome, were recorded using a visual analog scale postoperatively., Results: The PLSP scores 24 and 48 h after surgery were significantly lower in the two intervention groups than in the control group (P = 0.014 and P = 0.001, respectively), while no significant differences were observed between the two intervention groups., Conclusions: The single strategy using SI alone is as effective as the combined strategy of SI and RM for removing residual carbon dioxide and consequently preventing PLSP. Therefore, considering the potential risks of pulmonary or hemodynamic complications associated with RM, the single strategy using SI alone might be a better choice than the combined strategy.

Since their initial characterization as abundant brain proteins more than 5 decades ago, a resurgence into understanding the cellular functions of 14-3-3 proteins has emerged. While one of the earliest functions attributed to this eukaryotic scaffold protein family was the activation of enzymes involved in catecholamine and serotonin biosynthesis, 14-3-3 proteins have since been implicated in the regulation of several cellular processes including cell-cycle control, apoptosis, and metabolism. Moreover, increasing lines of evidence demonstrate links between changes in 14-3-3 protein function and the pathogenesis of chronic diseases. As a result, this has raised the question of whether 14-3-3 proteins represent viable targets for pharmacological intervention against diseases such as obesity, diabetes and cancer. In addition to providing an overview of the 14-3-3 protein family, we will discuss their connections to metabolism and metabolic diseases. We will also elaborate on the potential of targeting 14-3-3 proteins, as well as components of their interactomes, for developing novel therapies for treating metabolic diseases, including diabetes and obesity., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Among their pleiotropic functions, scaffold proteins are required for the accurate coordination of signaling pathways. It has only been within the past 10 years that their roles in glucose homeostasis and metabolism have emerged. It is well appreciated that changes in the expression or function of signaling effectors, such as receptors or kinases, can influence the development of chronic diseases such as diabetes and obesity. However, little is known regarding whether scaffolds have similar roles in the pathogenesis of metabolic diseases. In general, scaffolds are often underappreciated in the context of metabolism or metabolic diseases. In the present review, we discuss various scaffold proteins and their involvement in signaling pathways related to metabolism and metabolic diseases. The aims of the present review were to highlight the importance of scaffold proteins and to raise awareness of their physiological contributions. A thorough understanding of how scaffolds influence metabolism could aid in the discovery of novel therapeutic approaches to treat chronic conditions, such as diabetes, obesity, and cardiovascular disease, for which the incidence of all continue to increase at alarming rates.

Adipogenesis involves a complex signaling network requiring strict temporal and spatial organization of effector molecules. Molecular scaffolds, such as 14-3-3 proteins, facilitate such organization, and we have previously identified 14-3-3ζ as an essential scaffold in adipocyte differentiation. The interactome of 14-3-3ζ is large and diverse, and it is possible that novel adipogenic factors may be present within it, but this possibility has not yet been tested. Herein, we generated mouse embryonic fibroblasts from mice overexpressing a tandem affinity purification (TAP) epitope-tagged 14-3-3ζ molecule. After inducing adipogenesis, TAP-14-3-3ζ complexes were purified, followed by MS analysis to determine the 14-3-3ζ interactome. We observed more than 100 proteins that were unique to adipocyte differentiation, 56 of which were novel interacting partners. Among these, we were able to identify previously established regulators of adipogenesis ( i.e. Ptrf/Cavin1) within the 14-3-3ζ interactome, confirming the utility of this approach to detect adipogenic factors. We found that proteins related to RNA metabolism, processing, and splicing were enriched in the interactome. Analysis of transcriptomic data revealed that 14-3-3ζ depletion in 3T3-L1 cells affected alternative splicing of mRNA during adipocyte differentiation. siRNA-mediated depletion of RNA-splicing factors within the 14-3-3ζ interactome, that is, of Hnrpf, Hnrpk, Ddx6, and Sfpq, revealed that they have essential roles in adipogenesis and in the alternative splicing of Pparg and the adipogenesis-associated gene Lpin1 In summary, we have identified novel adipogenic factors within the 14-3-3ζ interactome. Further characterization of additional proteins within the 14-3-3ζ interactome may help identify novel targets to block obesity-associated expansion of adipose tissues., (© 2018 by The American Society for Biochemistry and Molecular Biology, Inc.)

Excess circulating insulin is associated with obesity in humans and in animal models. However, the physiologic causality of hyperinsulinemia in adult obesity has rightfully been questioned because of the absence of clear evidence that weight loss can be induced by acutely reversing diet-induced hyperinsulinemia. Herein, we describe the consequences of inducible, partial insulin gene deletion in a mouse model in which animals have already been made obese by consuming a high-fat diet. A modest reduction in insulin production/secretion was sufficient to cause significant weight loss within 5 wk, with a specific effect on visceral adipose tissue. This result was associated with a reduction in the protein abundance of the lipodystrophy gene polymerase I and transcript release factor ( Ptrf; Cavin) in gonadal adipose tissue. RNAseq analysis showed that reduced insulin and weight loss also associated with a signature of reduced innate immunity. This study demonstrates that changes in circulating insulin that are too fine to adversely affect glucose homeostasis nonetheless exert control over adiposity.-Page, M. M., Skovsø, S., Cen, H., Chiu, A. P., Dionne, D. A., Hutchinson, D. F., Lim, G. E., Szabat, M., Flibotte, S., Sinha, S., Nislow, C., Rodrigues, B., Johnson, J. D. Reducing insulin via conditional partial gene ablation in adults reverses diet-induced weight gain.

The causal relationships between insulin levels, insulin resistance, and longevity are not fully elucidated. Genetic downregulation of insulin/insulin-like growth factor 1 (Igf1) signaling components can extend invertebrate and mammalian lifespan, but insulin resistance, a natural form of decreased insulin signaling, is associated with greater risk of age-related disease in mammals. We compared Ins2 +/- mice to Ins2 +/+ littermate controls, on a genetically stable Ins1 null background. Proteomic and transcriptomic analyses of livers from 25-week-old mice suggested potential for healthier aging and altered insulin sensitivity in Ins2 +/- mice. Halving Ins2 lowered circulating insulin by 25%-34% in aged female mice, without altering Igf1 or circulating Igf1. Remarkably, decreased insulin led to lower fasting glucose and improved insulin sensitivity in aged mice. Moreover, lowered insulin caused significant lifespan extension, observed across two diverse diets. Our study indicates that elevated insulin contributes to age-dependent insulin resistance and that limiting basal insulin levels can extend lifespan., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)

Insulin modulates the biochemical pathways controlling lipid uptake, lipolysis and lipogenesis at multiple levels. Elevated insulin levels are associated with obesity, and conversely, dietary and pharmacological manipulations that reduce insulin have occasionally been reported to cause weight loss. However, the causal role of insulin hypersecretion in the development of mammalian obesity remained controversial in the absence of direct loss-of-function experiments. Here, we discuss theoretical considerations around the causal role of excess insulin for obesity, as well as recent studies employing mice that are genetically incapable of the rapid and sustained hyperinsulinemia that normally accompanies a high-fat diet. We also discuss new evidence demonstrating that modest reductions in circulating insulin prevent weight gain, with sustained effects that can persist after insulin levels normalize. Importantly, evidence from long-term studies reveals that a modest reduction in circulating insulin is not associated with impaired glucose homeostasis, meaning that body weight and lipid homeostasis are actually more sensitive to small changes in circulating insulin than glucose homeostasis in these models. Collectively, the evidence from new studies on genetic loss-of-function models forces a re-evaluation of current paradigms related to obesity, insulin resistance and diabetes. The potential for translation of these findings to humans is briefly discussed., (© 2017 Society for Endocrinology.)

Background: Menopause contributes to an increase in visceral fat mass and a decrease in muscle protein synthesis. Therefore, we performed this study to examine their relationship how effect the changes of body composition as obesity and sarcopenia on metabolic syndrome (MS) as a predictor of cardiovascular disease in postmenopausal women., Methods: Using data from the Korean National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2011, we estimated that 4,183 postmenopausal women underwent dual energy X-ray absorptiometry scans. Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight that was less than 1 standard deviation below the sex specific mean for the young reference group. After classification into four groups, the results were adjusted with menopausal age and hormonal treatment. The relationship between sarcopenic obesity (SO) and MS in postmenopausal women was analyzed by logistic regression analysis in a complex sampling., Results: In an unadjusted model, the odds ratio (OR) of MS for sarcopenia was 1.94 (95% confidence interval [CI], 1.52-2.49); the obesity group had an OR of 4.55 (95% CI, 3.63-5.71); and distinctly, the SO group had an OR of 6.26 (95% CI, 5.10-7.70). Even though there was controlling for variable adjustment, no definite difference was seen in the results., Conclusions: Sarcopenia and obesity were associated with MS independent of other metabolic impairment risk factors in both early menopausal and postmenopausal women. The results showed that, in particular, the prevalence of MS has increased more in postmenopausal women compared with previous research., Competing Interests: No potential conflict of interest relevant to this article was reported.

Multiple signaling pathways mediate the actions of metabolic hormones to control glucose homeostasis, but the proteins that coordinate such networks are poorly understood. We previously identified the molecular scaffold protein, 14-3-3ζ, as a critical regulator of in vitro β-cell survival and adipogenesis, but its metabolic roles in glucose homeostasis have not been studied in depth. Herein, we report that Ywhaz gene knockout mice (14-3-3ζKO) exhibited elevated fasting insulin levels while maintaining normal β-cell responsiveness to glucose when compared with wild-type littermate controls. In contrast with our observations after an ip glucose bolus, glucose tolerance was significantly improved in 14-3-3ζKO mice after an oral glucose gavage. This improvement in glucose tolerance was associated with significantly elevated fasting glucagon-like peptide-1 (GLP-1) levels. 14-3-3ζ knockdown in GLUTag L cells elevated GLP-1 synthesis and increased GLP-1 release. Systemic inhibition of the GLP-1 receptor attenuated the improvement in oral glucose tolerance that was seen in 14-3-3ζKO mice. When taken together these findings demonstrate novel roles of 14-3-3ζ in the regulation of glucose homeostasis and suggest that modulating 14-3-3ζ levels in intestinal L cells may have beneficial metabolic effects through GLP-1-dependent mechanisms.

Objective: The role and mechanisms of insulin receptor internalization remain incompletely understood. Previous trafficking studies of insulin receptors involved fluorescent protein tagging at their termini, manipulations that may be expected to result in dysfunctional receptors. Our objective was to determine the trafficking route and molecular mechanisms of functional tagged insulin receptors and endogenous insulin receptors in pancreatic beta-cells., Methods: We generated functional insulin receptors tagged with pH-resistant fluorescent proteins between domains. Confocal, TIRF and STED imaging revealed a trafficking pattern of inter-domain tagged insulin receptors and endogenous insulin receptors detected with antibodies., Results: Surprisingly, interdomain-tagged and endogenous insulin receptors in beta-cells bypassed classical Rab5a- or Rab7-mediated endocytic routes. Instead, we found that removal of insulin receptors from the plasma membrane involved tyrosine-phosphorylated caveolin-1, prior to trafficking within flotillin-1-positive structures to lysosomes. Multiple methods of inhibiting caveolin-1 significantly reduced Erk activation in vitro or in vivo, while leaving Akt signaling mostly intact., Conclusions: We conclude that phosphorylated caveolin-1 plays a role in insulin receptor internalization towards lysosomes through flotillin-1-positive structures and that caveolin-1 helps bias physiological beta-cell insulin signaling towards Erk activation.

Molecular scaffolds are often viewed as passive signaling molecules that facilitate protein-protein interactions. However, new evidence gained from the use of loss-of-function or gain-of-function models is dispelling this notion. Our own recent discovery of 14-3-3ζ as an essential regulator of adipogenesis highlights the complex roles of this member of the 14-3-3 protein family. Depletion of the 14-3-3ζ isoform affected parallel pathways that drive adipocyte development, including pathways controlling the stability of key adipogenic transcription factors and cell cycle progression. Going beyond adipocyte differentiation, this study opens new avenues of research in the context of metabolism, as 14-3-3ζ binds to a variety of well-established metabolic proteins that harbor its canonical phosphorylation binding motifs. This suggests that 14-3-3ζ may contribute to key metabolic signaling pathways, such as those that facilitate glucose uptake and fatty acid metabolism. Herein, we discuss these novel areas of research, which will undoubtedly shed light onto novel roles of 14-3-3ζ, and perhaps its related family members, on glucose homeostasis.

The proteins that coordinate complex adipogenic transcriptional networks are poorly understood. 14-3-3ζ is a molecular adaptor protein that regulates insulin signalling and transcription factor networks. Here we report that 14-3-3ζ-knockout mice are strikingly lean from birth with specific reductions in visceral fat depots. Conversely, transgenic 14-3-3ζ overexpression potentiates obesity, without exacerbating metabolic complications. Only the 14-3-3ζ isoform is essential for adipogenesis based on isoform-specific RNAi. Mechanistic studies show that 14-3-3ζ depletion promotes autophagy-dependent degradation of C/EBP-δ, preventing induction of the master adipogenic factors, Pparγ and C/EBP-α. Transcriptomic data indicate that 14-3-3ζ acts upstream of hedgehog signalling-dependent upregulation of Cdkn1b/p27(Kip1). Indeed, concomitant knockdown of p27(Kip1) or Gli3 rescues the early block in adipogenesis induced by 14-3-3ζ knockdown in vitro. Adipocyte precursors in 14-3-3ζKO embryos also appear to have greater Gli3 and p27(Kip1) abundance. Together, our in vivo and in vitro findings demonstrate that 14-3-3ζ is a critical upstream driver of adipogenesis.

Background: Pancreatic adenocarcinoma is one of the most lethal cancers, yet it remains understudied and poorly understood. Hyperinsulinemia has been reported to be a risk factor of pancreatic cancer, and the rapid rise of hyperinsulinemia associated with obesity and type 2 diabetes foreshadows a rise in cancer incidence. However, the actions of insulin at the various stages of pancreatic cancer progression remain poorly defined., Methods: Here, we examined the effects of a range of insulin doses on signalling, proliferation and survival in three human cell models meant to represent three stages in pancreatic cancer progression: primary pancreatic duct cells, the HPDE immortalized pancreatic ductal cell line, and the PANC1 metastatic pancreatic cancer cell line. Cells were treated with a range of insulin doses, and their proliferation/viability were tracked via live cell imaging and XTT assays. Signal transduction was assessed through the AKT and ERK signalling pathways via immunoblotting. Inhibitors of AKT and ERK signalling were used to determine the relative contribution of these pathways to the survival of each cell model., Results: While all three cell types responded to insulin, as indicated by phosphorylation of AKT and ERK, we found that there were stark differences in insulin-dependent proliferation, cell viability and cell survival among the cell types. High concentrations of insulin increased PANC1 and HPDE cell number, but did not alter primary duct cell proliferation in vitro. Cell survival was enhanced by insulin in both primary duct cells and HPDE cells. Moreover, we found that primary cells were more dependent on AKT signalling, while HPDE cells and PANC1 cells were more dependent on RAF/ERK signalling., Conclusions: Our data suggest that excessive insulin signalling may contribute to proliferation and survival in human immortalized pancreatic ductal cells and metastatic pancreatic cancer cells, but not in normal adult human pancreatic ductal cells. These data suggest that signalling pathways involved in cell survival may be rewired during pancreatic cancer progression.

A nonconjugated anionic polyelectrolyte, poly(sodium 4-styrenesulfonate) (PSS-Na), was applied to the optoelectronic devices as an interfacial layer (IFL) at the semiconducting layer/cathode interface. The ultraviolet photoelectron spectroscopy and the Kelvin probe microscopy studies support the formation of a favorable interface dipole at the organic/cathode interface. For polymer light-emitting diodes (PLEDs), the maximum luminance efficiency (LEmax) and the turn-on voltage (Von) of the device with a layer of PSS-Na spin-coated from the concentration of 0.5 mg/mL were 3.00 cd/A and 5.5 V, which are dramatically improved than those of the device without an IFL (LEmax = 0.316 cd/A, Von = 9.5 V). This suggests that the PSS-Na film at the emissive layer/cathode interface improves the electron injection ability. As for polymer solar cells (PSCs), the power conversion efficiency (PCE) of the device with a layer of PSS-Na spin-coated from the concentration of 0.5 mg/mL was 2.83%, which is a 16% increase compared to that of the PSC without PSS-Na. The PCE improvement is mainly due to the enhancement of the short-circuit current (12% increase). The results support that the electron collection and transporting increase by the introduction of the PSS-Na film at the photoactive layer/cathode interface. The improvement of the efficiency of the PLED and PSC is due to the reduction of the Schottky barrier by the formation of a favorable interface as well as the better Ohmic contact at the cathode interface.

Women from high-risk families consider preventive measures for breast cancer including screening. Guidelines on screening differ considerably regarding starting age. We investigated whether age at diagnosis in affected relatives is predictive for age at diagnosis. We analyzed the age of breast cancer detection of 1,304 first- and second-degree relatives of 314 BRCA1, 164 BRCA2 and 244 high-risk participants of the Dutch MRI-SCreening study. The within- and between-family variance in the relative's age at diagnosis was analyzed with a random effect linear regression model. We compared the starting age of screening based on risk-group (25 years for BRCA1, 30 years for BRCA2 and 35 years for familial risk), on family history, and on the model, which combines both. The findings were validated in 63 families from the UK-MARIBS study. Mean age at diagnosis in the relatives varied between families; 95% range of mean family ages was 35-55 in BRCA1-, 41-57 in BRCA2- and 44-60 in high-risk families. In all, 14% of the variance in age at diagnosis, in BRCA1 even 23%, was explained by family history, 7% by risk group. Determining start of screening based on the model and on risk-group gave similar results in terms of cancers missed and years of screening. The approach based on familial history only, missed more cancers and required more screening years in both the Dutch and the United Kingdom data sets. Age at breast cancer diagnosis is partly dependent on family history which may assist planning starting age for preventive measures., (Copyright © 2013 UICC.)

Insulin signaling is essential for β-cell survival and proliferation in vivo. Insulin also has potent mitogenic and anti-apoptotic actions on cultured β-cells, with maximum effect in the high picomolar range and diminishing effect at high nanomolar doses. In order to understand whether these effects of insulin are constitutive or can be subjected to physiological modulation, it is essential to estimate the extracellular concentration of monomeric insulin within an intact islet. Unfortunately, the in vivo concentration of insulin monomers within the islet cannot be measured directly with current technology. Here, we present the first mathematical model designed to estimate the levels of monomeric insulin within the islet extracellular space. Insulin is released as insoluble crystals that exhibit a delayed dissociation into hexamers, dimers, and eventually monomers, which only then can act as signaling ligands. The rates at which different forms of insulin dissolve in vivo have been estimated from studies of peripheral insulin injection sites. We used this and other information to formulate a mathematical model to estimate the local insulin concentration within a single islet as a function of glucose. Model parameters were estimated from existing literature. Components of the model were validated using experimental data, if available. Model analysis predicted that the majority of monomeric insulin in the islet is that which has been returned from the periphery, and the concentration of intra-islet monomeric insulin varies from ~50-300 pM when glucose is in the physiological range. Thus, our results suggest that the local concentration of monomeric insulin within the islet is in the picomolar 'sweet spot' range of insulin doses that activate the insulin receptor and have the most potent effects on β-cells in vitro. Together with experimental data, these estimations support the concept that autocrine/paracrine insulin signalling within the islet is dynamic, rather than constitutive and saturated.

Aims/hypothesis: Diabetes is characterised by pancreatic beta cell death and dysfunction, resulting from unbalanced pro-survival and pro-death signalling. The 14-3-3 proteins are molecular adaptors that integrate numerous signalling pathways, including the v-raf-leukaemia viral oncogene 1 (RAF1)/B cell leukaemia/lymphoma 2 (BCL-2)-associated agonist of cell death (BAD) pathway, which we have previously implicated in insulin-dependent beta cell survival. Nevertheless, the roles of 14-3-3 proteins in beta cell fate and function have not been investigated., Methods: We examined the abundance, localisation, modulation and roles of 14-3-3 proteins using quantitative RT-PCR, immunoblot or imaging. MIN6 cells or mouse islets cells were manipulated with inhibitors, short interfering RNA (siRNA) or plasmids overexpressing 14-3-3., Results: We first characterised the abundance and subcellular location of all seven 14-3-3 isoforms in mouse and human beta cells. Most isoforms were cytoplasmic, except 14-3-3σ, which appeared to be nuclear. Analysis of 14-3-3 abundance under stress conditions revealed distinct modulation in mouse islets and MIN6 cells. Generalised 14-3-3 inhibition promoted apoptosis and dysfunction, and siRNA-mediated knockdown revealed isoform-specific roles in caspase-3-dependent beta cell apoptosis, with a clear role for 14-3-3ζ. Overabundance of 14-3-3ζ sequestered BAD-BCL2-associated X protein (BAX) from mitochondria, attenuated Dp5 (also known as Hrk) and Puma (also known as Bbc3) induction, and increased survival in response to pro-inflammatory cytokines or thapsigargin. Anti-apoptotic insulin treatment increased the sequestration of BAD/BAX by 14-3-3ζ. BAD mutants that were unable to bind 14-3-3ζ localised to mitochondria and induced apoptosis., Conclusions/interpretation: This first study of the 14-3-3 family in beta cells revealed specific regulation, localisation and anti-apoptotic roles among the isoforms. Focus on 14-3-3ζ revealed its importance in preventing BAD-BAX mitochondrial localisation and protecting beta cells from multiple stresses. Thus, some 14-3-3 proteins are pro-survival signalling hubs.

Hyperinsulinemia is associated with obesity and pancreatic islet hyperplasia, but whether insulin causes these phenomena or is a compensatory response has remained unsettled for decades. We examined the role of insulin hypersecretion in diet-induced obesity by varying the pancreas-specific Ins1 gene dosage in mice lacking Ins2 gene expression in the pancreas, thymus, and brain. Age-dependent increases in fasting insulin and β cell mass were absent in Ins1(+/-):Ins2(-/-) mice fed a high-fat diet when compared to Ins1(+/+):Ins2(-/-) littermate controls. Remarkably, Ins1(+/-):Ins2(-/-) mice were completely protected from diet-induced obesity. Genetic prevention of chronic hyperinsulinemia in this model reprogrammed white adipose tissue to express uncoupling protein 1 and increase energy expenditure. Normalization of adipocyte size and activation of energy expenditure genes in white adipose tissue was associated with reduced inflammation, reduced fatty acid spillover, and reduced hepatic steatosis. Thus, we provide genetic evidence that pathological circulating hyperinsulinemia drives diet-induced obesity and its complications., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Diabetes is associated with the death and dysfunction of insulin-producing pancreatic β-cells. In other systems, Musashi genes regulate cell fate via Notch signaling, which we recently showed regulates β-cell survival. Here we show for the first time that human and mouse adult islet cells express mRNA and protein of both Musashi isoforms, as well Numb/Notch/Hes/neurogenin-3 pathway components. Musashi expression was observed in insulin/glucagon double-positive cells during human fetal development and increased during directed differentiation of human embryonic stem cells (hESCs) to the pancreatic lineage. De-differentiation of β-cells with activin A increased Msi1 expression. Endoplasmic reticulum (ER) stress increased Msi2 and Hes1, while it decreased Ins1 and Ins2 expression, revealing a molecular link between ER stress and β-cell dedifferentiation in type 2 diabetes. These effects were independent of changes in Numb protein levels and Notch activation. Overexpression of MSI1 was sufficient to increase Hes1, stimulate proliferation, inhibit apoptosis and reduce insulin expression, whereas Msi1 knockdown had the converse effects on proliferation and insulin expression. Overexpression of MSI2 resulted in a decrease in MSI1 expression. Taken together, these results demonstrate overlapping, but distinct roles for Musashi-1 and Musashi-2 in the control of insulin expression and β-cell proliferation. Our data also suggest that Musashi is a novel link between ER stress and the compensatory β-cell proliferation and the loss of β-cell gene expression seen in specific phases of the progression to type 2 diabetes.

Regulation of glucose homeostasis by insulin depends on pancreatic β-cell growth, survival, and function. Raf-1 kinase is a major downstream target of several growth factors that promote proliferation and survival of many cell types, including the pancreatic β cells. We have previously reported that insulin protects β cells from apoptosis and promotes proliferation by activating Raf-1 signaling in cultured human islets, mouse islets, and MIN6 cells. As Raf-1 activity is critical for basal apoptosis and insulin secretion in vitro, we hypothesized that Raf-1 may play an important role in glucose homeostasis in vivo. To test this hypothesis, we utilized the Cre-loxP recombination system to obtain a pancreatic β-cell-specific ablation of Raf-1 kinase gene (RIPCre(+/+):Raf-1(flox/flox)) and a complete set of littermate controls (RIPCre(+/+):Raf-1(wt/wt)). RIPCre(+/+):Raf-1(flox/flox) mice were viable, and no effects on weight gain were observed. RIPCre(+/+):Raf-1(flox/flox) mice had increased fasting blood glucose levels and impaired glucose tolerance but normal insulin tolerance compared to littermate controls. Insulin secretion in vivo and in isolated islets was markedly impaired, but there was no apparent effect on the exocytosis machinery. However, islet insulin protein and insulin 2 mRNA, but not insulin 1 mRNA, were dramatically reduced in Raf-1-knockout mice. Analysis of insulin 2 knockout mice demonstrated that this reduction in mRNA was sufficient to impair in vivo insulin secretion. Our data further indicate that Raf-1 specifically and acutely regulates insulin 2 mRNA via negative action on Foxo1, which has been shown to selectively control the insulin 2 gene. This work provides the first direct evidence that Raf-1 signaling is essential for the regulation of basal insulin transcription and the supply of releasable insulin in vivo.

Background: As part of the Magnetic Resonance Imaging for Breast Screening (MARIBS), Study women with a family history of breast cancer were assessed psychologically to determine the relative psychological impact and acceptability of annual screening using magnetic resonance imaging (MRI) and conventional X-ray mammography (XRM)., Methods: Women were assessed psychologically at baseline (4 weeks before MRI and XRM), immediately before, and immediately after, both MRI and XRM, and at follow-up (6 weeks after the scans)., Results: Overall, both procedures were found to be acceptable with high levels of satisfaction (MRI, 96.3% and XRM, 97.7%; NS) and low levels of psychological morbidity throughout, particularly at 6-week follow-up. Low levels of self-reported distress were reported for both procedures (MRI, 13.5% and XRM, 7.8%), although MRI was more distressing (P=0.005). Similarly, higher anticipatory anxiety was reported before MRI than before XRM (P=0.003). Relative to XRM, MRI-related distress was more likely to persist at 6 weeks after the scans in the form of intrusive MRI-related thoughts (P=0.006) and total MRI-related distress (P=0.014). More women stated that they intended to return for XRM (96.3%) than for MRI (88%; P<0.0005). These effects were most marked for the first year of screening, although they were also statistically significant in subsequent years., Conclusion: Given the proven benefits of MRI in screening for breast cancer in this population, these data point to the urgent need to provide timely information and support to women undergoing MRI.

Rho GTPases, such as cell division cycle 42 (Cdc42) and ras-related C3 botulinum toxin substrate 1 (Rac1), have been identified as regulators of F-actin dynamics and hormone release from endocrine cells; however, their role in secretion of the incretin hormone, glucagon-like peptide-1 (GLP-1), from the enteroendocrine L cell is unknown. Insulin induced a 1.4-fold increase in L cell GLP-1 release; however, secretion was potentiated to 2.1-fold in the presence of the F-actin depolymerizing agent, latrunculin B, suggesting that F-actin functions as a permissive barrier. In murine GLUTag L cells, insulin stimulated F-actin depolymerization and Cdc42 activation simultaneously, and these events occurred prior to detectable increases in insulin-induced GLP-1 release. After insulin treatment, Cdc42-dependent p21-activated kinase-1 (PAK1) activation was also detected, and transfection of small-interfering RNA against Cdc42 or of dominant-negative Cdc42(T17N) impaired insulin-stimulated PAK1 activation, actin remodeling, and GLP-1 secretion. Overexpression of kinase-dead PAK1(K299R) or PAK1 small interfering RNA similarly attenuated insulin-induced GLP-1 secretion. Knockdown or inhibition of Cdc42 and PAK1 activities also prevented activation of MAPK/ERK (MEK)-1/2-ERK1/2 by insulin, which was previously identified as a critical pathway for insulin-regulated GLP-1 release. Taken together, these data identify a novel signaling pathway in the endocrine L cell, whereby Cdc42 regulates actin remodeling, activation of the cannonical 1/2-ERK1/2 pathway and PAK1, and GLP-1 secretion in response to insulin.

Introduction: A UK multicenter study compared the performance of contrast enhanced-magnetic resonance imaging with X-Ray Mammography in women at high-risk of breast cancer commencing in 1997. Selection criteria were used to identify women with at least 0.9% annual risk of breast cancer., Methods: Women at high breast cancer risk, with a strong family history and/or high probability of a BRCA1/BRCA2/TP53 mutation, were recruited from 22 centers. Those not known as gene carriers were asked to give a blood sample, which was tested anonymously for mutations. Women ages 35 to 49 years were offered annual screening for 2 to 7 years. Study eligibility at entry was assessed retrospectively by detailed examination of pedigrees and overall eligibility accounting for computer risk assessment and mutation results., Results: Seventy-eight of 837 (9%) women entered for screening were ineligible using the strict entry criteria. Thirty-nine cancers were detected in 1,869 women-years in study (incidence 21 per 1,000). Including 3,561 further years follow-up, 28 more breast cancers were identified (12 of 1,000). Incidence rates for 759 eligible women were 22 of 1,000 in study and 13 of 1,000 in total follow-up, compared with 9 of 1,000 and 4 of 1,000, respectively, in 78 ineligible women. Breast cancer rates were higher for BRCA2 than BRCA1 after testing anonymized samples in this selected population at 65 of 1,000 in study and 36 of 1,000 in total follow-up for BRCA2 compared with 44 of 1,000 and 27 of 1,000 for BRCA1., Conclusions: Strict enforcement of study criteria would have minimally improved the power of the study, whereas testing for BRCA1/2 in advance would have substantially increased the detection rates.

Insulin resistance and type 2 diabetes mellitus are associated with impaired postprandial secretion of glucagon-like peptide-1 (GLP-1), a potent insulinotropic hormone. The direct effects of insulin and insulin resistance on the L cell are unknown. We therefore hypothesized that the L cell is responsive to insulin and that insulin resistance impairs GLP-1 secretion. The effects of insulin and insulin resistance were examined in well-characterized L cell models: murine GLUTag, human NCI-H716, and fetal rat intestinal cells. MKR mice, a model of chronic hyperinsulinemia, were used to assess the function of the L cell in vivo. In all cells, insulin activated the phosphatidylinositol 3 kinase-Akt and MAPK kinase (MEK)-ERK1/2 pathways and stimulated GLP-1 secretion by up to 275 +/- 58%. Insulin resistance was induced by 24 h pretreatment with 10(-7) m insulin, causing a marked reduction in activation of Akt and ERK1/2. Furthermore, both insulin-induced GLP-1 release and secretion in response to glucose-dependent insulinotropic peptide and phorbol-12-myristate-13-acetate were significantly attenuated. Whereas inhibition of phosphatidylinositol 3 kinase with LY294002 potentiated insulin-induced GLP-1 release, secretion was abrogated by inhibiting the MEK-ERK1/2 pathway with PD98059 or by overexpression of a kinase-dead MEK1-ERK2 fusion protein. Compared with controls, MKR mice were insulin resistant and displayed significantly higher fasting plasma insulin levels. Furthermore, they had significantly higher basal GLP-1 levels but displayed impaired GLP-1 secretion after an oral glucose challenge. These findings indicate that the intestinal L cell is responsive to insulin and that insulin resistance in vitro and in vivo is associated with impaired GLP-1 secretion.