8 research outputs found

    Extracellular Vesicles of Hypoxic Adipocytes and Obese Subjects Reduce Insulin-stimulated Glucose Uptake

    Get PDF
    Scope We investigate the effects of extracellular vesicles (EVs) obtained from in vitro adipocyte cell models and from obese subjects on glucose transport and insulin responsiveness. Methods and results EVs are isolated from the culture supernatant of adipocytes cultured under normoxia, hypoxia (1% oxygen), or exposed to macrophage conditioned media (15% v/v). EVs are isolated from the plasma of lean individuals and subjects with obesity. Cultured adipocytes are incubated with EVs and activation of insulin signalling cascades and insulin‐stimulated glucose transport are measured. EVs released from hypoxic adipocytes impair insulin‐stimulated 2‐deoxyglucose uptake and reduce insulin mediated phosphorylation of AKT. Insulin‐mediated phosphorylation of extracellular regulated kinases (ERK1/2) is not affected. EVs from individuals with obesity decrease insulin stimulated 2‐deoxyglucose uptake in adipocytes (p = 0.0159). Conclusion EVs released by stressed adipocytes impair insulin action in neighboring adipocytes

    Extracellular vesicles from hypoxic adipocytes and obese subjects reduce insulin-stimulated glucose uptake

    Get PDF
    Scope We investigate the effects of extracellular vesicles (EVs) obtained from in vitro adipocyte cell models and from obese subjects on glucose transport and insulin responsiveness. Methods and results EVs are isolated from the culture supernatant of adipocytes cultured under normoxia, hypoxia (1% oxygen), or exposed to macrophage conditioned media (15% v/v). EVs are isolated from the plasma of lean individuals and subjects with obesity. Cultured adipocytes are incubated with EVs and activation of insulin signalling cascades and insulin‐stimulated glucose transport are measured. EVs released from hypoxic adipocytes impair insulin‐stimulated 2‐deoxyglucose uptake and reduce insulin mediated phosphorylation of AKT. Insulin‐mediated phosphorylation of extracellular regulated kinases (ERK1/2) is not affected. EVs from individuals with obesity decrease insulin stimulated 2‐deoxyglucose uptake in adipocytes (p = 0.0159). Conclusion EVs released by stressed adipocytes impair insulin action in neighboring adipocytes

    The New Faces of Role Conflicts among Young Polish Polish in the Context of Combining Parenting with University Education and Employment

    No full text
    This article discusses combining parenthood and the practice of parenting with university education and work. The situation of experiencing the overlap of the roles of a mother/father, an employee, and a student constitutes a specific exemplification of challenges and role conflicts experienced by young people who seek to manage social contexts that are mutually competitive. These young people’s situation results from the broader social context wherein pursuing university degrees is extremely typical of young Polish men and women, while the student population encompasses both parents and people with established careers. The empirical material used for this article stems from a qualitative study conducted in 2017 and 2018. The material for the article comprises 30 analysed interviews with students and alumni who – at the time of the research – were combining parenthood with both work and university education. The respondents had at least one child aged 0 to 15 whilst actively pursuing a degree. The results show the existence of role conflicts and reveal that the conflicts vary and depend on social factors such as gender, social support, and institutional assistance. The role conflicts are strictly tied to the ‘greedy institutions’ notion applied to education, parenting, and employment. A certain normalization of combining all three aspects within a single biographical timeline was observed, with a concurrent outcome of respondents having strong desires to be successful across all those fields.Tematykę artykułu stanowi łączenie rodzicielstwa ze studiami i pracą zawodową, które jest wyjątkową egzemplifikacją współczesnego nakładania się ról i wyzwań wynikających z konfliktu doświadczanego przez młode osoby realizujące jednocześnie liczne, konkurencyjne względem siebie role społeczne. Jest to efekt wyłaniający się z szerszego kontekstu społecznego, w którym zdobywanie wykształcenia na poziomie wyższym jest coraz powszechniejsze wśród młodych Polek i Polaków, a w szeregach studentów nie brakuje rodziców i osób o ugruntowanej pozycji na rynku pracy. Bazą empiryczną artykułu jest materiał zebrany w badaniu jakościowym przeprowadzonym na przełomie 2017 i 2018 roku. Na potrzeby artykułu przeanalizowano 30 wywiadów z jednocześnie pracującymi i studiującymi rodzicami. Respondenci łączą lub łączyli pracę zawodową, zdobywanie dyplomu uczelni oraz wychowywanie dzieci w różnym wieku (od 0 do 15 lat). Zaprezentowane wyniki wskazują na występowanie konfliktu ról, jednocześnie pokazując zróżnicowanie i uzależnienie poczucia konfliktu od takich elementów jak płeć, wsparcie społeczne czy też instytucjonalne. Konflikt w tej analizie jest ściśle powiązany z koncepcją „chciwych instytucji”, jakimi są edukacja, rodzicielstwo i praca zawodowa. Widoczna jest również normalizacja łączenia tych trzech aspektów życia jednostki przy jednoczesnym poczuciu konieczności realizowania się na wszystkich polach

    Abundance of Cytochromes in Hepatic Extracellular Vesicles Is Altered by Drugs Related With Drug‐Induced Liver Injury

    No full text
    Drug‐induced liver injury (DILI) is a serious worldwide health problem that accounts for more than 50% of acute liver failure. There is a great interest in clinical diagnosis and pharmaceutical industry to elucidate underlying molecular mechanisms and find noninvasive biomarkers for this pathology. Cell‐secreted extracellular vesicles (EVs) have provided a new biological source to identify low disease invasive markers. Despite the intense research developed on these vesicles, there is currently a gap on their patho‐physiological effects. Here, we study EVs secreted by primary rat hepatocytes challenged with galactatosamine (GalN), acetaminophen, or diclofenac as DILI in vitromodels. Proteomics analysis of these EVs revealed an increase in enzymes already associated with liver damage, such as catecholamine‐methyl transferase and arginase 1. An increase in translation‐related proteins and a decrease in regulators of apoptosis were also observed. In addition, we show the presence of enzymatic activity of P450 cytochrome 2d1 in EVs. The activity specifically is decreased in EVs secreted by hepatocytes after acetaminophen treatment and increased in EVs derived from GalN‐treated hepatocytes. By using in vivo preclinical models, we demonstrate the presence of this cytochrome activity in circulation under normal conditions and an increased activity after GalN‐induced injury. Conclusion: Hepatocyte‐secreted EVs carry active xenobiotic‐metabolizing enzymes that might be relevant in extracellular metabolism of drugs and be associated with DILI. (Hepatology Communications 2018;0:00‐00

    Differences in the metabolite composition and mechanical properties of extracellular vesicles secreted by hepatic cellular models

    No full text
    Liver constitutes the major metabolic factory in the organism and is involved in the synthesis, secretion and clearance of many blood-circulating molecules. Previously, we have characterised the protein and RNA cargo of extracellular vesicles (EVs) secreted by two hepatic cellular models, a mouse hepatocyte progenitor cell line (MLP29) and primary rat hepatocytes (RHs). Here, we report the metabolome profile of these vesicles by performing a targeted UHPLC-MS metabolomics analysis of these two cellular models and their respective secreted EVs. Visual inspection of the data through principal component analysis allows clear separation of the metabolic profile of cells and EVs, and also of both cellular models. Correlation matrix supported that lipid composition of EVs is mainly determined by parent cell composition. EVs derived from MLP29 and RHs showed a negative correlation in their percentage composition of ceramides, glycerophospholipids, sphingomyelins and triglycerides. Metabolites enriched in EVs were also different depending on the cellular model. EVs secreted by MLP29 were enriched in different species of sphingomyelins and ceramides underrepresented in EVs secreted by RHs. Remarkably, triglycerides constitute an important percentage of the composition of EVs derived from RHs. We further investigate if the differences in lipid composition were also accompanied by differences in mechanical behaviour, by using atomic force microscopy complemented with nanoindentation-based methodology. To compare the stiffness and brittleness of EVs derived from MLP29 cell line and RH primary cells, FZ curves were performed in the centre of single vesicles and the differences found in their force-vs.-indentation curves suggest that RHs EVs are softer (less stiff) and less resistance to mechanical failure than MLP29 EVs. Therefore, we can conclude that EVs from different origin carry a characteristic lipid composition related to their parental cell composition, and exhibit different mechanical properties. Abbreviations: For the identification of the different species of lipids, the following abbreviations has been employed: Cer, ceramide; ChoE, Cholesteryl Ester; CMH, monohexosylceramide; DAG, diglycerid; LPC, lysophosphatidylcholin; LPI, lysophosphatidyinositol; PC, phosphocoline; PE, phoethanolamine; PI, phosphoinositol; SM, sphingomyelin; TAG, triglyceri

    Lipidomics and biodistribution of extracellular vesicles‐secreted by hepatocytes from Zucker lean and fatty rats

    No full text
    Abstract Extracellular vesicles (EVs) have been involved in metabolic syndrome, although their specific role in the development of the pathology is still unknown. To further study the role of EVs, we have analysed by Raman tweezers microspectroscopy and mass spectrometry‐based lipidomics the small EVs population secreted by fatty (ZF) and lean (ZL) hepatocytes obtained from Zucker rats. We have also explored in vivo and ex vivo biodistribution of these EVs through fluorine‐18‐radiolabelling using a positron emission tomography imaging. Based on the proportion of proteins to lipids and the types of lipids, our results indicate that within the range of small EVs, primary hepatocytes secrete different subpopulations of particles. These differences were observed in the enrichment of triglyceride species in EVs secreted by ZF hepatocytes. Biodistribution experiments showed accumulation in the brain, heart, lungs, kidney and specially in bladder after intravenous administration. In summary, we show that EVs released by a fatty hepatocytes carry a different lipid signature compared to their lean counterpart. Biodistribution experiment has shown no difference in the distribution of EVs secreted by ZF and ZL hepatocytes but has given us a first view of possible target organs for these particles. Our results might open a door to both pathology studies and therapeutic interventions

    Decreased serum prohepcidin concentration in patients with polycythemia vera*

    No full text
    Objective: Iron deficiency is a common complication in patients with polycythemia vera (PV). Hepcidin is a principal regulator of iron homeostasis. The aim of our study was to assess prohepcidin, a hepcidin precursor, and other iron status parameters in the serum of PV patients. Methods: The study was performed in 60 patients (F/M 26/34) aged 38~84 (66±10) years. The control group consisted of 20 healthy volunteers, age and sex matched. The following parameters were determined in blood serum samples: prohepcidin concentration, iron content, unsaturated iron binding capacity (UIBC), total iron binding capacity (TIBC), transferrin saturation (TfS), and concentrations of ferritin and soluble transferrin receptor (sTfR). Results: All PV patients showed significantly lower levels of prohepcidin, higher levels of sTfR and TIBC compared to the control group. 40% of the patients from the study group showed concentrations of ferritin below the normal range and significantly lower levels of serum iron and TfS, and significantly higher levels of sTfR, UIBC and TIBC in comparison with the rest of the study group. In this group of patients, prohepcidin concentrations were significantly lower than those in other patients. Conclusion: The results indicate that PV patients suffer from iron metabolism disorders. The decreased serum level of prohepcidin in PV patients may be a result of iron deficiency
    corecore