Syncytiotrophoblast‐derived extracellular vesicles carry apolipoprotein‐E and affect lipid synthesis of liver cells in vitro

Summary1. Separated leukocytes or total blood from normal subjects, untreated leukaemic patients and from leukaemic patients treated with cytostatic agents were incubated with CH3COONa-l-C14. Radioactivity of mixed lipids was measured at standard time intervals.2. The time incorporation curve observed with leukocytes from treated leukaemic patients showed after an initial linear part, a more rapid levelling off than the curves observed with leukocytes from untreated and normal subjects.3. Therefore, an indirect effect of treatment on leukocyte lipid synthesis seems to be present.4. Phospholipid and neutral lipid synthesis by leukaemic leukocytes was also studied. The results give no evidence that these fractions as a whole have any precursor-product relation.

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STUDIES ON OESTROGENS IN CATTLE

Acta Endocrinologica ◽

10.1530/acta.0.xxxiv0027 ◽

1960 ◽

Vol XXXIV (I) ◽

pp. 27-32 ◽

Cited By ~ 6

Author(s):

Stian Erichsen ◽

Weiert Velle

Keyword(s):

Bovine Liver ◽

Liver Cells ◽

Cell Sheets ◽

Confluent Cell

ABSTRACT The metabolism of some oestrogenic hormones was studied in vitro by the use of cells grown on a medium free from blood. The methods used for the culture of cells from bovine testis, endometrium, amnion, and liver in confluent cell sheets on glass are described. The interconversion of oestrone and oestradiol-17β was demonstrated in the presence of cells from amnion, endometrium, and also from testicles of young calves and bulls. Only trace amounts of oestrone were found following incubations with oestradiol-17α in these tissues. Bovine liver cells grown in vitro showed a very poor capacity to bring about the interconversion mentioned above.

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In Vitro Diabetogenic Effect of Cadmium on Liver

International Journal of Current Pharmaceutical Review and Research ◽

10.25258/ijcprr.v8i01.9093 ◽

2017 ◽

Vol 8 (01) ◽

Author(s):

Agung Biworo ◽

Dwi Rezki Amalia ◽

Gratianus Billy Himawan ◽

Lisda Rizky Amalia ◽

Valentina Halim ◽

...

Keyword(s):

Glucose Metabolism ◽

Liver Homogenate ◽

Liver Cells ◽

Male Rats ◽

Glycogen Level ◽

Liver Sample ◽

Km Value ◽

Cd Exposure ◽

Menten Constant

The objectives of this study were to determine the effect of cadmium (Cd) on glucose metabolism disruption in liver cells homogenate in vitro. The glucose metabolism disruption was analyzed by measuring the level of liver glucose, glycogen and methylglyoxal (MG), and the activity of glucokinase activity. In this experiment, a liver sample was taken from male rats (Rattus novergicus). Samples then homogenized and divided into four groups with; C served as control which contains liver homogenate only; T1 which contains liver homogenate + 0.03 mg/l of cadmium sulphate (CdSO4); T2 which contains liver homogenate + 0.3 mg/l of CdSO4; and T3 which contains liver homogenate + 3 mg/l of CdSO4. After treatment, liver glucose, glycogen, and MG levels, and glucokinase activity were estimated. The activity of liver glucokinase was estimated by measuring the Michaelis-Menten constant (Km) value. The results revealed that Cd exposure could significantly increase glucose and MG levels, the Km value of glucokinase, and decreased the glycogen level in liver cells (P>0.05). These results indicated that Cd exposure induced the disruption of glucose metabolism in the liver.

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AAnti-Inflammatory Effects of Plasma Circulating Exosomes Obtained from Normal-Weight and Obese Subjects on Hepatocytes

Endocrine Metabolic & Immune Disorders - Drug Targets ◽

10.2174/1871530320666200505121426 ◽

2020 ◽

Vol 20 ◽

Author(s):

Reza Afrisham ◽

Sahar Sadegh-Nejadi ◽

Reza Meshkani ◽

Solaleh Emamgholipour ◽

Molood Bagherieh ◽

...

Keyword(s):

Inflammatory Cytokines ◽

Hepg2 Cells ◽

Human Liver ◽

Liver Cells ◽

Normal Weight ◽

Protein Levels ◽

Human Liver Cells ◽

Tnf Α ◽

Anti Inflammatory

Introduction: Obesity is a disorder with low-grade chronic inflammation that plays a key role in the hepatic inflammation and steatosis. Moreover, there are studies to support the role of exosomes in the cellular communications, the regulation of metabolic homeostasis and immunomodulatory activity. Accordingly, we aimed to evaluate the influence of plasma circulating exosomes derived from females with normal-weight and obesity on the secretion of inflammatory cytokines in human liver cells. Methods: Plasma circulating exosomes were isolated from four normal (N-Exo) and four obese (O-Exo) women. The exosomes were characterized and approved for CD63 expression (common exosomal protein marker) and morphology/size using the western blot and TEM methods, respectively. The exosomes were used for stimulation of HepG2 cells in vitro. After 24 h incubation, the protein levels of TNF-α,IL-6, and IL-1β were measured in the culture supernatant of HepG2 cells using the ELISA kit. Results: The protein levels of IL-6 and TNF-α in the cells treated with O-Exo and N-Exo reduced significantly in comparison with control group (P=0.039 and P<0.001 respectively), while significance differences were not found between normal and obese groups (P=0.808, and P=0.978 respectively). However, no significant differences were found between three groups in term of IL-1β levels (P=0.069). Based on the correlation analysis, the protein levels of IL-6 were positively correlated with TNF-α (r 0.978, P<0.001). Conclusion: These findings suggest that plasma circulating exosomes have probably anti-inflammatory properties independently from body mass index and may decrease the secretion of inflammatory cytokines in liver. However, further investigations in vitro and in vivo are needed to address the anti-inflammatory function of N-Exo and O-Exo in human liver cells and/or other cells.

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Effects of Antimalarial Drugs and Clofibrate on in vitro Lipid Synthesis in Tetrahymena pyriformis GL

Pharmacology ◽

10.1159/000136520 ◽

1974 ◽

Vol 12 (1) ◽

pp. 48-56 ◽

Cited By ~ 5

Author(s):

H.Y.M. Pan ◽

S.C. Chou ◽

K.A. Conklin

Keyword(s):

Lipid Synthesis ◽

Tetrahymena Pyriformis ◽

Antimalarial Drugs

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A Systematic Review on Extracellular Vesicles-Enriched Fat Grafting: A Shifting Paradigm

Aesthetic Surgery Journal ◽

10.1093/asj/sjaa362 ◽

2020 ◽

Author(s):

Mohammad Ghiasloo ◽

Laura De Wilde ◽

Kashika Singh ◽

Patrick Tonnard ◽

Alexis Verpaele ◽

...

Keyword(s):

Systematic Review ◽

Graft Survival ◽

Extracellular Vesicles ◽

Retention Rate ◽

Fat Grafting ◽

Retention Rates ◽

Fat Graft ◽

Cochrane Central Register

Abstract Background Recent evidence confirms that mesenchymal stem cells (MSCs) facilitate angiogenesis mainly through paracrine function. Extracellular vesicles (EVs) are regarded as key components of the cell secretome, possessing functional properties of their source cells. Subsequently, MSC-EVs have emerged as a novel cell-free approach to improve fat graft retention rate. Objectives To provide a systematic review of all studies reporting the use of MSC-EVs to improve graft retention rate. Methods A systematic search was undertaken using the Embase, PubMed and the Cochrane Central Register of Controlled Trials databases. Outcome measures included donor/receptor organism of the fat graft, study model, intervention groups, evaluation intervals, EV research data, in vitro and in vivo results. Results Of the total 1717 articles, 62 full-texts were screened. Seven studies reporting on 294mice were included. Overall, EV treated groups showed higher graft retention rates compared to untreated groups. Notably, retention rate was similar following EV- and MSC-treatment. In addition to reduced inflammation, graft enrichment with EVs resulted in early revascularization and better graft integrity. Interestingly, hypoxic preconditioning of MSCs improved their beneficial paracrine effects and led to a more proangiogenic EV population, as observed by both in vitro and in vivo results. Conclusions MSC-EVs appear to offer an interesting cell-free alternative to improve fat graft survival. While their clinical relevance remains to be determined, it is clear that not the cells, but their secretome is essential for graft survival. Thus, a paradigm shift from cell-assisted lipotransfer towards ‘secretome-assisted lipotransfer’ is well on its way.

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Plant-Derived Extracellular Vesicles: Current Findings,Challenges, and Future Applications

Membranes ◽

10.3390/membranes11060411 ◽

2021 ◽

Vol 11 (6) ◽

pp. 411

Author(s):

Nader Kameli ◽

Anya Dragojlovic-Kerkache ◽

Paul Savelkoul ◽

Frank R. Stassen

Keyword(s):

Human Health ◽

Extracellular Vesicles ◽

Preliminary Results ◽

In Vivo Experiments ◽

Health And Disease ◽

Conducting Research ◽

Protocol Standardization ◽

Insight Into

In recent years, plant-derived extracellular vesicles (PDEVs) have gained the interest of many experts in fields such as microbiology and immunology, and research in this field has exponentially increased. These nano-sized particles have provided researchers with a number of interesting findings, making their application in human health and disease very promising. Both in vitro and in vivo experiments have shown that PDEVs can exhibit a multitude of effects, suggesting that these vesicles may have many potential future applications, including therapeutics and nano-delivery of compounds. While the preliminary results are promising, there are still some challenges to face, such as a lack of protocol standardization, as well as knowledge gaps that need to be filled. This review aims to discuss various aspects of PDEV knowledge, including their preliminary findings, challenges, and future uses, giving insight into the complexity of conducting research in this field.

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Large extracellular vesicles in the left atrial appendage in patients with atrial fibrillation—the missing link?

Clinical Research in Cardiology ◽

10.1007/s00392-021-01873-4 ◽

2021 ◽

Author(s):

Andreas Zietzer ◽

Baravan Al-Kassou ◽

Paul Jamme ◽

Verena Rolfes ◽

Eva Steffen ◽

...

Keyword(s):

Atrial Fibrillation ◽

Extracellular Vesicles ◽

Left Atrial ◽

Left Atrial Appendage ◽

Thrombus Formation ◽

Flow Cytometric Analysis ◽

Heart Rhythm ◽

Atrial Appendage ◽

Peripheral Embolization

AbstractAtrial fibrillation (AF) is the most frequent arrhythmic disease in humans, which leads to thrombus formation in the left atrial appendage and stroke through peripheral embolization. Depending on their origin, large extracellular vesicles (lEVs) can exert pro-coagulant functions. In the present study, we investigated how different types of AF influence the levels of large EV subtypes in three distinct atrial localizations. Blood samples were collected from the right and left atrium and the left atrial appendage of 58 patients. 49% of the patients had permanent AF, 34% had non-permanent AF, and 17% had no history of AF. Flow cytometric analysis of the origin of the lEVs showed that the proportion of platelet-derived lEVs in the left atrial appendage was significantly higher in permanent AF patients compared to non-permanent AF. When we grouped patients according to their current heart rhythm, we also detected significantly higher levels of platelet-derived lEVs in the left atrial appendage (LAA) in patients with atrial fibrillation. In vitro studies revealed, that platelet activation with lipopolysaccharide (LPS) leads to higher levels of miR-222-3p and miR-223-3p in platelet-derived lEVs. Treatment with lEVs from LPS- or thrombin-activated platelets reduces the migration of endothelial cells in vitro. These results suggest that permanent atrial fibrillation is associated with increased levels of platelet-derived lEVs in the LAA, which are potentially involved in LAA thrombus formation.

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Lipoproteins Are Responsible for the Pro-Inflammatory Property of Staphylococcus aureus Extracellular Vesicles

International Journal of Molecular Sciences ◽

10.3390/ijms22137099 ◽

2021 ◽

Vol 22 (13) ◽

pp. 7099

Author(s):

Pradeep Kumar Kopparapu ◽

Meghshree Deshmukh ◽

Zhicheng Hu ◽

Majd Mohammad ◽

Marco Maugeri ◽

...

Keyword(s):

Extracellular Vesicles ◽

Inflammatory Responses ◽

Surface Proteins ◽

Host Cells ◽

Immune Stimulation ◽

Domains Of Life ◽

Major Surface ◽

Staphylococcal Aureus

Staphylococcal aureus (S. aureus), a Gram-positive bacteria, is known to cause various infections. Extracellular vesicles (EVs) are a heterogeneous array of membranous structures secreted by cells from all three domains of life, i.e., eukaryotes, bacteria, and archaea. Bacterial EVs are implied to be involved in both bacteria–bacteria and bacteria–host interactions during infections. It is still unclear how S. aureus EVs interact with host cells and induce inflammatory responses. In this study, EVs were isolated from S. aureus and mutant strains deficient in either prelipoprotein lipidation (Δlgt) or major surface proteins (ΔsrtAB). Their immunostimulatory capacities were assessed both in vitro and in vivo. We found that S. aureus EVs induced pro-inflammatory responses both in vitro and in vivo. However, this activity was dependent on lipidated lipoproteins (Lpp), since EVs isolated from the Δlgt showed no stimulation. On the other hand, EVs isolated from the ΔsrtAB mutant showed full immune stimulation, indicating the cell wall anchoring of surface proteins did not play a role in immune stimulation. The immune stimulation of S. aureus EVs was mediated mainly by monocytes/macrophages and was TLR2 dependent. In this study, we demonstrated that not only free Lpp but also EV-imbedded Lpp had high pro-inflammatory activity.

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695 Oral delivery of a microbial extracellular vesicle induces potent anti-tumor immunity in mice

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-sitc2020.0695 ◽

2020 ◽

Vol 8 (Suppl 3) ◽

pp. A737-A737

Author(s):

Loise Francisco-Anderson ◽

Mary Abdou ◽

Michael Goldberg ◽

Erin Troy ◽

...

Keyword(s):

Tumor Microenvironment ◽

Tumor Growth ◽

Extracellular Vesicles ◽

Tumor Immunity ◽

Extracellular Vesicle ◽

The Body ◽

Checkpoint Inhibition ◽

Small Intestinal ◽

The Impact

BackgroundThe small intestinal axis (SINTAX) is a network of anatomic and functional connections between the small intestine and the rest of the body. It acts as an immunosurveillance system, integrating signals from the environment that affect physiological processes throughout the body. The impact of events in the gut in the control of tumor immunity is beginning to be appreciated. We have previously shown that an orally delivered single strain of commensal bacteria induces anti-tumor immunity preclinically via pattern recognition receptor-mediated activation of innate and adaptive immunity. Some bacteria produce extracellular vesicles (EVs) that share molecular content with the parent bacterium in a particle that is roughly 1/1000th the volume in a non-replicating form. We report here an orally-delivered and gut-restricted bacterial EV which potently attenuates tumor growth to a greater extent than whole bacteria or checkpoint inhibition.MethodsEDP1908 is a preparation of extracellular vesicles produced by a gram-stain negative strain of bacterium of the Oscillospiraceae family isolated from a human donor. EDP1908 was selected for its immunostimulatory profile in a screen of EVs from a range of distinct microbial strains. Its mechanism of action was determined by ex vivo analysis of the tumor microenvironment (TME) and by in vitro functional studies with murine and human cells.ResultsOral treatment of tumor-bearing mice with EDP1908 shows superior control of tumor growth compared to checkpoint inhibition (anti-PD-1) or an intact microbe. EDP1908 significantly increased the percentage of IFNγ and TNF producing CD8+ CTLs, NK cells, NKT cells and CD4+ cells in the tumor microenvironment (TME). EDP1908 also increased tumor-infiltrating dendritic cells (DC1 and DC2). Analysis of cytokines in the TME showed significant increases in IP-10 and IFNg production in mice treated with EDP1908, creating an environment conducive to the recruitment and activation of anti-tumor lymphocytes.ConclusionsThis is the first report of striking anti-tumor effects of an orally delivered microbial extracellular vesicle. These data point to oral EVs as a new class of immunotherapeutic drugs. They are particularly effective at harnessing the biology of the small intestinal axis, acting locally on host cells in the gut to control distal immune responses within the TME. EDP1908 is in preclinical development for the treatment of cancer.Ethics ApprovalPreclinical murine studies were conducted under the approval of the Avastus Preclinical Services’ Ethics Board. Human in vitro samples were attained by approval of the IntegReview Ethics Board; informed consent was obtained from all subjects.

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