Reduced expression of chemerin in visceral adipose tissue associates with hepatic steatosis in patients with obesity

Objective: This study aimed to evaluate whether circulating levels and/or visceral adipose tissue (VAT) expression of recently described adipokines associate with histopathological severity of nonalcoholic fatty liver disease (NAFLD), independent of obesity and insulin resistance. Methods: Serum levels of adiponectin, omentin, chemerin, monocyte chemoattractant protein-1, and secreted frizzled-related protein 4 were measured using enzyme-linked immunosorbent assay in 81 patients with obesity and NAFLD and 18 lean control subjects. Expression in VAT was measured using real-time PCR and histopathological grading was scored using the NAFLD activity score (NAS). Results: When NAFLD patients were subdivided into groups with simple steatosis, borderline nonalcoholic steatohepatitis (NASH), and NASH, adiponectin serum levels and omentin expression were lower in NASH versus simple steatosis patients. Serum adiponectin was generally lower with higher histopathological grading. Chemerin VAT expression was negatively associated with NAS (r = -0.331, P = 0.022) and steatosis score (r = -0.335, P = 0.020), independent of age, BMI, and HOMA-IR. In addition, adjusting for chemerin VAT expression in a multivariate model explained part of the association between NAS and HOMA-IR. Conclusions: These findings suggest that lower VAT expression of chemerin in patients with obesity may be involved in the pathophysiology of hepatic steatosis, potentially by modulating the link between insulin resistance and NAFLD

Ceruloplasmin is a novel adipokine which is overexpressed in adipose tissue of obese subjects and in obesity-associated cancer cells

Obesity confers an increased risk of developing specific cancer forms. Although the mechanisms are unclear, increased fat cell secretion of specific proteins (adipokines) may promote/facilitate development of malignant tumors in obesity via cross-talk between adipose tissue(s) and the tissues prone to develop cancer among obese. We searched for novel adipokines that were overexpressed in adipose tissue of obese subjects as well as in tumor cells derived from cancers commonly associated with obesity. For this purpose expression data from human adipose tissue of obese and non-obese as well as from a large panel of human cancer cell lines and corresponding primary cells and tissues were explored. We found expression of ceruloplasmin to be the most enriched in obesity-associated cancer cells. This gene was also significantly up-regulated in adipose tissue of obese subjects. Ceruloplasmin is the body's main copper carrier and is involved in angiogenesis. We demonstrate that ceruloplasmin is a novel adipokine, which is produced and secreted at increased rates in obesity. In the obese state, adipose tissue contributed markedly (up to 22%) to the total circulating protein level. In summary, we have through bioinformatic screening identified ceruloplasmin as a novel adipokine with increased expression in adipose tissue of obese subjects as well as in cells from obesity-associated cancers. Whether there is a causal relationship between adipose overexpression of ceruloplasmin and cancer development in obesity cannot be answered by these cross-sectional comparisons

Hypothalamic Wnt signalling and its role in energy balance regulation

yesWnt signalling and its downstream effectors are well known for their roles in embryogenesis and tumourigenesis, including the regulation of cell proliferation, survival and differentiation. In the nervous system, Wnt signalling has been described mainly during embryonic development, although accumulating evidence suggests that it also plays a major role in adult brain morphogenesis and function. Studies have predominantly concentrated on memory formation in the hippocampus, although recent data indicate that Wnt signalling is also critical for neuroendocrine control of the developed hypothalamus, a brain centre that is key in energy balance regulation and whose dysfunction is implicated in metabolic disorders such as type 2 diabetes and obesity. Based on scattered findings that report the presence of Wnt molecules in the tanycytes and ependymal cells lining the third ventricle and arcuate nucleus neurones of the hypothalamus, their potential importance in key regions of food intake and body weight regulation has been investigated in recent studies. The present review brings together current knowledge on Wnt signalling in the hypothalamus of adult animals and discusses the evidence suggesting a key role for members of the Wnt signalling family in glucose and energy balance regulation in the hypothalamus in diet-induced and genetically obese (leptin deficient) mice. Aspects of Wnt signalling in seasonal (photoperiod sensitive) rodents are also highlighted, given the recent evidence indicating that the Wnt pathway in the hypothalamus is not only regulated by diet and leptin, but also by photoperiod in seasonal animals, which is connected to natural adaptive changes in food intake and body weight. Thus, Wnt signalling appears to be critical as a modulator for normal functioning of the physiological state in the healthy adult brain, and is also crucial for normal glucose and energy homeostasis where its dysregulation can lead to a range of metabolic disorders

Knockdown of SF-1 and RNF31 Affects Components of Steroidogenesis, TGFβ, and Wnt/β-catenin Signaling in Adrenocortical Carcinoma Cells

The orphan nuclear receptor Steroidogenic Factor-1 (SF-1, NR5A1) is a critical regulator of development and homeostasis of the adrenal cortex and gonads. We recently showed that a complex containing E3 ubiquitin ligase RNF31 and the known SF-1 corepressor DAX-1 (NR0B1) interacts with SF-1 on target promoters and represses transcription of steroidogenic acute regulatory protein (StAR) and aromatase (CYP19) genes. To further evaluate the role of SF-1 in the adrenal cortex and the involvement of RNF31 in SF-1-dependent pathways, we performed genome-wide gene-expression analysis of adrenocortical NCI-H295R cells where SF-1 or RNF31 had been knocked down using RNA interference. We find RNF31 to be deeply connected to cholesterol metabolism and steroid hormone synthesis, strengthening its role as an SF-1 coregulator. We also find intriguing evidence of negative crosstalk between SF-1 and both transforming growth factor (TGF) β and Wnt/β-catenin signaling. This crosstalk could be of importance for adrenogonadal development, maintenance of adrenocortical progenitor cells and the development of adrenocortical carcinoma. Finally, the SF-1 gene profile can be used to distinguish malignant from benign adrenocortical tumors, a finding that implicates SF-1 in the development of malignant adrenocortical carcinoma

Wnt antagonist secreted frizzled-related protein 4 upregulates adipogenic differentiation in human adipose tissue-derived mesenchymal stem cells

With more than 1.4 billion overweight or obese adults worldwide, obesity and progression of the metabolic syndrome are major health and economic challenges. To address mechanisms of obesity, adipose tissue-derived mesenchymal stem cells (ADSCs) are being studied to detail the molecular mechanisms involved in adipogenic differentiation. Activation of the Wnt signalling pathway has inhibited adipogenesis from precursor cells. In our study, we examined this anti-adipogenic effect in further detail stimulating Wnt with lithium chloride (LiCl) and 6-bromo indirubin 3'oxime (BIO). We also examined the effect of Wnt inhibition using secreted frizzled-related protein 4 (sFRP4), which we have previously shown to be pro-apoptotic, anti-angiogenic, and anti-tumorigenic. Wnt stimulation in LiCl and BIOtreated ADSCs resulted in a significant reduction (2.7-fold and 12-fold respectively) in lipid accumulation as measured by Oil red O staining while Wnt inhibition with sFRP4 induced a 1.5-fold increase in lipid accumulation. Furthermore, there was significant 1.2-fold increase in peroxisome proliferator-activated receptor gamma (PPAR ?) and CCAAT/enhancer binding protein alpha (C/EBPa), and 1.3-fold increase in acetyl CoA carboxylase protein levels. In contrast, the expression of adipogenic proteins (PPAR?, C/EBPa, and acetyl CoA carboxylase) were decreased significantly with LiCl (by 1.6, 2.6, and 1.9-fold respectively) and BIO (by 7, 17, and 5.6-fold respectively) treatments. These investigations demonstrate interplay between Wnt antagonism and Wnt activation during adipogenesis and indicate pathways for therapeutic intervention to control this process

HOIL-1L Interacting Protein (HOIP) as an NF-κB Regulating Component of the CD40 Signaling Complex

The tumor necrosis factor receptor (TNFR) superfamily mediates signals critical for regulation of the immune system. One family member, CD40, is important for the efficient activation of antibody-producing B cells and other antigen-presenting cells. The molecules and mechanisms that mediate CD40 signaling are only partially characterized. Proteins known to interact with the cytoplasmic domain of CD40 include members of the TNF receptor-associated factor (TRAF) family, which regulate signaling and serve as links to other signaling molecules. To identify additional proteins important for CD40 signaling, we used a combined stimulation/immunoprecipitation procedure to isolate CD40 signaling complexes from B cells and characterized the associated proteins by mass spectrometry. In addition to known CD40-interacting proteins, we detected SMAC/DIABLO, HTRA2/Omi, and HOIP/RNF31/PAUL/ZIBRA. We found that these previously unknown CD40-interacting partners were recruited in a TRAF2-dependent manner. HOIP is a ubiquitin ligase capable of mediating NF-κB activation through the ubiquitin-dependent activation of IKKγ. We found that a mutant HOIP molecule engineered to lack ubiquitin ligase activity inhibited the CD40-mediated activation of NF-κB. Together, our results demonstrate a powerful approach for the identification of signaling molecules associated with cell surface receptors and indicate an important role for the ubiquitin ligase activity of HOIP in proximal CD40 signaling

Wnt proteins contribute to neuromuscular junction formation through distinct signaling pathways

International audienceUnderstanding the developmental steps that shape formation of the neuromuscular junction (NMJ) connecting motoneurons to skeletal muscle fibers is crucial. Wnt morphogens are key players in the formation of this specialized peripheral synapse, but their individual and collaborative functions and downstream pathways remain poorly understood at the NMJ. Here, we demonstrate through Wnt4 and Wnt11 gain-of-function studies in cell culture or in mice that Wnts enhance acetylcholine receptor (AChR) clustering and motor axon outgrowth. By contrast, loss of Wnt11 or Wnt-dependent signaling in vivo decreases AChR clustering and motor nerve terminal branching. Both Wnt4 and Wnt11 stimulate AChR mRNA levels and AChR clustering downstream of activation of the β-catenin pathway. Strikingly, Wnt4 and Wnt11 co-immunoprecipitate with Vangl2, a core component of the planar cell polarity (PCP) pathway, which accumulates at embryonic NMJs. Moreover, mice bearing a Vangl2 loss-of-function mutation (loop-tail) exhibit fewer AChR clusters and overgrowth of motor axons bypassing AChR clusters. Together, our results provide genetic and biochemical evidence that Wnt4 and Wnt11 cooperatively contribute to mammalian NMJ formation through activation of both the canonical and Vangl2-dependent core PCP pathways

Discovery of widespread transcription initiation at microsatellites predictable by sequence-based deep neural network

Using the Cap Analysis of Gene Expression (CAGE) technology, the FANTOM5 consortium provided one of the most comprehensive maps of transcription start sites (TSSs) in several species. Strikingly, ~72% of them could not be assigned to a specific gene and initiate at unconventional regions, outside promoters or enhancers. Here, we probe these unassigned TSSs and show that, in all species studied, a significant fraction of CAGE peaks initiate at microsatellites, also called short tandem repeats (STRs). To confirm this transcription, we develop Cap Trap RNA-seq, a technology which combines cap trapping and long read MinION sequencing. We train sequence-based deep learning models able to predict CAGE signal at STRs with high accuracy. These models unveil the importance of STR surrounding sequences not only to distinguish STR classes, but also to predict the level of transcription initiation. Importantly, genetic variants linked to human diseases are preferentially found at STRs with high transcription initiation level, supporting the biological and clinical relevance of transcription initiation at STRs. Together, our results extend the repertoire of non-coding transcription associated with DNA tandem repeats and complexify STR polymorphism

Palvelukartta Espoon 18–29-vuotiaiden nuorten hyvinvointipalveluista Vamos-nuorten näkökulmasta

Nuorten syrjäytyminen on ollut viime vuosina runsaasti esillä mediassa. Syrjäytymisellä voi olla kauaskantoisiakin seurauksia, joilla on vaikutuksensa niin yksilöön, yhteisöön kuin yhteiskuntaankin. Syrjäytymisvaarassa olevien nuorten tukeminen ja syrjäytymisen ehkäisy mahdollistuu varhaisen tuen ja puuttumisen avulla esimerkiksi erilaisten matalankynnyksen palveluiden kautta. Opinnäytetyömme tarkoituksena oli tuottaa yhdessä Vamoksen asiakasnuorten kanssa palvelukartta Espoon alueen palveluista, jotka on suunnattu 18-29–vuotiaille nuorille. Palvelukartan laatimisen taustalla oli Vamoksen työntekijöiltä saatu idea informatiivisesta julisteesta, johon olisi koostettu Espoon alueen nuorille suunnattuja palveluja sekä kuvailtu lyhyesti niiden sisältöä. Palvelukartan sisältämän tiedon kerääminen tapahtui ryhmätyöskentelynä, yhteensä viitenä erillisenä toimintakertana. Tarkoituksena oli, että palvelukartasta syntyisi työkalu Vamoksen työntekijöille. Työskentelyn keskiössä olivat nuoret ja heidän asiantuntijuutensa. Puhuimme tässä opinnäyteyössä palveluista hyvinvointipalveluina. Hyödynsimme Learning cafe-menetelmää toimintakerroilla tehtävässä tiedonkeruussa. Tavoitteena oli osallistaa nuoria toiminnalliseen työskentelyyn ja kasvattaa nuorten tietoisuutta heille tarjotuista hyvinvointipalveluista Espoon alueella. Opinnäytetyön perusoletuksena oli, että tieto nuorille suunnatuista palveluista ei kohtaa tarpeeksi hyvin palveluiden käyttäjiä eli nuoria. Vamos Espoossa tehtävän palveluohjauksen tueksi haluttiin kehittää työkalu, jonka avulla voisi hahmottaa pirstaleista palvelukenttää. Palvelukartan arviointi perustui työntekijöiden näkemyksiin palvelukartan käyttökelpoisuudesta ja kehittämismahdollisuuksista. Arvioimme toiminnallista osuutta ja tavoitteidemme toteutumista havaintoihimme perustuvan itsearvioinnin sekä nuorilta saadun palautteen avulla. Arvioimme myös opinnäytetyöprosessia, ammatillista kasvuamme sekä palvelukarttaa ja sen kehittämistä. Työntekijöiden palautteiden mukaan palvelukarttaa voisi käyttää työvälineenä palveluiden läpikäymisessä yhdessä nuoren kanssa tai esimerkiksi uusien työntekijöiden perehdyttämisessä.The social exclusion of young people has been widely discussed in the media for the past few years. Social exclusion can create far-reaching effects that occur on an individual and societal level. Supporting young people that are in danger of social exclusion and preventing social exclusion is possible with early interference and different low-threshold services. The purpose of this functional thesis was to create a map of different services provided for people aged 18-29 years in co-operation with the young clients in Vamos Espoo. The idea for this project came from the employees of Vamos Espoo. They wanted to create an informative poster that would present different services and their contents and purposes in Espoo area. The functional part of this thesis consisted of working together with the young in Vamos Espoo organizing group activities for them. All in all we carried out five group work sessions in which we managed to produce the material for the map of services. The purpose in this thesis was to create a working method for the employees. The focus of this project was on the young and their experiences and expertise. In this thesis the focus is on welfare services. Learning café method was used as the working method and all the information needed about the welfare services was gathered. The goal was to participate the young in this project in the group work sessions and also to increase their knowledge of welfare services located in Espoo area. The basic assumption of this thesis was that the information does not reach the possible service users, such as the young. The work and guidance carried out in Vamos Espoo needed a working method that would assist in the situation and introduce different services effectively just on one page. The evaluation of this thesis was based on the views of the employees’ and their visions regarding to using the map of welfare services and how to develop it as a working method. The evaluation of the functional part as well as the reaching of our goals was based on self-evaluation and feedback from the young. The process, professional growth and the map that was created was also evaluated by us. Based on the employee’s feedback the map of welfare services could be used as a working method for example while introducing the different services to clients or when inducting a new employee to their work