Post - prandial rise of microvesicles in peripheral blood of healthy human donors

<p>Abstract</p> <p>Background</p> <p>Microvesicles isolated from body fluids are membrane - enclosed fragments of cell interior which carry information on the status of the organism. It is yet unclear how metabolism affects the number and composition of microvesicles in isolates from the peripheral blood.</p> <p>Aim</p> <p>To study the post - prandial effect on microvesicles in isolates from the peripheral blood of 21 healthy donors, in relation to blood cholesterol and blood glucose concentrations.</p> <p>Results</p> <p>The average number of microvesicles in the isolates increased 5 hours post - prandially by 52%; the increase was statistically significant (p = 0.01) with the power P = 0.68, while the average total blood cholesterol concentration, average low density lipoprotein cholesterol concentration (LDL-C) and average high density lipoprotein cholesterol concentration (HDL-C) all remained within 2% of their fasting values. We found an 11% increase in triglycerides (p = 0.12) and a 6% decrease in blood glucose (p < 0.01, P = 0.74). The post - prandial number of microvesicles negatively correlated with the post - fasting total cholesterol concentration (r = - 0.46, p = 0.035) while the difference in the number of microvesicles in the isolates between post - prandial and post - fasting states negatively correlated with the respective difference in blood glucose concentration (r = - 0.39, p = 0.05).</p> <p>Conclusions</p> <p>In a population of healthy human subjects the number of microvesicles in isolates from peripheral blood increased in the post - prandial state. The increase in the number of microvesicles was affected by the fasting concentration of cholesterol and correlated with the decrease in blood glucose.</p

Hybridosomes from spruce needle homogenate

Introduction: Being of compatible structure with biomembranes, lipid–based nanoparticles are considered as convenient platforms for drug delivery systems. In the proposed work we considered formation of lipid nanovesicles associated with bioactive phytochemicals from spruce needle homogenate (here called hybridosomes). We formed hybridosomes by mixing appropriate amounts of lecithin, supernatant of isolation of extracellular particles from spruce needle homogenate and glycerol. Methods: We visualized hybridosomes by light microscopy and cryogenic transmission electron microscopy and assessed them by flow cytometry, dynamic light scattering, ultraviolet–visual spectroscopy and interferometric microscopy. Results: We found that the particles consisted of a bilayer membrane and a fluid-like interior. Flow cytometry and interferometric light microscopy measurements showed that the majority of the particles were nano-sized. Dynamic light scattering and interferometric light microscopy measurements agreed well with the determined average hydrodynamic radius of the particles Rh (between 140 and 180 nm) while their number densities were in the range between 10^13 and 10^14/mL indicating that hybridosomes present about 2/3 of the mixture, excluding solvent and other small molecules. Discussion: Simple and low-cost preparation method, non-demanding saving process and efficient formation procedure suggest that large scale production of hybridosomes from lipids and spruce needle homogenate is feasible.Small New World 2.0 4-5 September 2023., Graz, Austri

Characterization of Nanohybridosomes from Lipids and Spruce Homogenate Containing Extracellular Vesicles

Introduction: Lipid nanovesicles associated with bioactive phytochemicals from spruce needle homogenate (here called nano-sized hybridosomes or nanohybridosomes, NSHs) were considered. Methods: We formed NSHs by mixing appropriate amounts of lecithin, glycerol and supernatant of isolation of extracellular vesicles from spruce needle homogenate. We visualized NSHs by light microscopy and cryogenic transmission electron microscopy and assessed them by flow cytometry, dynamic light scattering, ultraviolet–visual spectroscopy, interferometric light microscopy and liquid chromatography–mass spectrometry. Results: We found that the particles consisted of a bilayer membrane and a fluid-like interior. Flow cytometry and interferometric light microscopy measurements showed that the majority of the particles were nano-sized. Dynamic light scattering and interferometric light microscopy measurements agreed well on the average hydrodynamic radius of the particles Rh (between 140 and 180 nm), while the concentrations of the particles were in the range between 1013 and 1014/mL indicating that NSHs present a considerable (more than 25%) of the sample which is much more than the yield of natural extracellular vesicles (EVs) from spruce needle homogenate (estimated less than 1%). Spruce specific lipids and proteins were found in hybridosomes. Discussion: Simple and low-cost preparation method, non-demanding saving process and efficient formation procedure suggest that large-scale production of NSHs from lipids and spruce needle homogenate is feasible. Plain Language Summary: Cells shed into their exterior nanoparticles (here referred to as extracellular vesicles – EVs) that are free to move, reach distant cells and are taken up by them. As they carry bioactive constituents, EVs may have important impact on the recipient cells. The mechanisms of EV formation and mediation can be employed in designing therapeutic, prophylactic and diagnostic methods for various medical issues. EVs can be harvested from biological samples; however, their yield is small,12 and there are potential side effects. Artificial vesicles – liposomes – have high yield; however, in vivo, they can be degraded before reaching the target and their reproducibility is yet insufficient. In order to combine advantages of both types of nanoparticles, we have composed nanohybridosomes (NSHs) from soya lecithin, water and supernatant of isolation of EVs from spruce needle homogenate, visualized them by cryogenic electron microscopy and characterized them with respect to their size, concentration and protein/nucleic acid content. We have applied a recently developed interferometric light microscopy to determine the hydrodynamic radius and the concentration of EVs. We found that the majority of composed particles are nano-sized and that they enclose more than 25% of the incoming volume of liquid, which is considerably more than about 1% that can be harvested by isolation of EVs from spruce needle homogenate by (ultra) centrifugatio

Hybridosomes from spruce needle homogenate

Introduction: Being of compatible structure with biomembranes, lipid–based nanoparticles are considered as convenient platforms for drug delivery systems. In the proposed work we considered formation of lipid nanovesicles associated with bioactive phytochemicals from spruce needle homogenate (here called hybridosomes). We formed hybridosomes by mixing appropriate amounts of lecithin, supernatant of isolation of extracellular particles from spruce needle homogenate and glycerol. Methods: We visualized hybridosomes by light microscopy and cryogenic transmission electron microscopy and assessed them by flow cytometry, dynamic light scattering, ultraviolet–visual spectroscopy and interferometric microscopy. Results: We found that the particles consisted of a bilayer membrane and a fluid-like interior. Flow cytometry and interferometric light microscopy measurements showed that the majority of the particles were nano-sized. Dynamic light scattering and interferometric light microscopy measurements agreed well with the determined average hydrodynamic radius of the particles Rh (between 140 and 180 nm) while their number densities were in the range between 10^13 and 10^14/mL indicating that hybridosomes present about 2/3 of the mixture, excluding solvent and other small molecules. Discussion: Simple and low-cost preparation method, non-demanding saving process and efficient formation procedure suggest that large scale production of hybridosomes from lipids and spruce needle homogenate is feasible.Small New World 2.0 4-5 September 2023., Graz, Austri

Minimal Information for Studies of Extracellular Vesicles 2018 (MISEV2018): A Position Statement of the International Society for Extracellular Vesicles and Update of the MISEV2014 Guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

Biological properties of extracellular vesicles and their physiological functions

In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored. Here, we provide a comprehensive overview of the current understanding of the physiological roles of EVs, which has been written by crowd-sourcing, drawing on the unique EV expertise of academia-based scientists, clinicians and industry based in 27 European countries, the United States and Australia. This review is intended to be of relevance to both researchers already working on EV biology and to newcomers who will encounter this universal cell biological system. Therefore, here we address the molecular contents and functions of EVs in various tissues and body fluids from cell systems to organs. We also review the physiological mechanisms of EVs in bacteria, lower eukaryotes and plants to highlight the functional uniformity of this emerging communication system

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points