• Title/Summary/Keyword: Vesicles

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Characterization of Biocompatible Lipid-Based Vesicles Contained with Medicinal Herb Extracts

  • Lee, Kyu-Jin;Park, Sun young;Park, Geuntae
    • Journal of Environmental Science International
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    • v.27 no.10
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    • pp.853-863
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    • 2018
  • In order to increase the medicinal herbs efficiency of drug delivery, vesicles contained with medicinal herbs were prepared by phosphatidylcholines and surface active agent. Vesicles loaded with medicinal herbs were characterized by UV-spectroscopy, Zetasizer. The antioxidant activity of vesicles was measured by DPPH assay and ABTS radical scavenging assays. Also, an analysis was conducted to determine the effects of anti-inflammatory of vesicles contained medicinal herbs. In addition, the whitening effects of vesicles contained medicinal herbs extract were studied via tyrosinase inhibition assay. The results of vesicles were as follows. Vesicles appeared an average diameter of approximatively 164-599 nm. All studied vesicles contained with medicinal herbs showed antioxidant, anti-inflammatory and whitening effects in a dose-dependent manner. Therefore, this experiment achieves its purpose of synthesizing of vesicles. In conclusion, we recommended that the vesicles loaded with medicinal herbs have ability for anti-aging materials. Specifically, it will apply to cosmetic ingredients.

Methods of measuring presynaptic function with fluorescence probes

  • Yeseul Jang;Sung Rae Kim;Sung Hoon Lee
    • Applied Microscopy
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    • v.51
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    • pp.2.1-2.7
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    • 2021
  • Synaptic vesicles, which are endogenous to neurotransmitters, are involved in exocytosis by active potentials and release neurotransmitters. Synaptic vesicles used in neurotransmitter release are reused via endocytosis to maintain a pool of synaptic vesicles. Synaptic vesicles show different types of exo- and endocytosis depending on animal species, type of nerve cell, and electrical activity. To accurately understand the dynamics of synaptic vesicles, direct observation of synaptic vesicles is required; however, it was difficult to observe synaptic vesicles of size 40-50 nm in living neurons. The exo-and endocytosis of synaptic vesicles was confirmed by labeling the vesicles with a fluorescent agent and measuring the changes in fluorescence intensity. To date, various methods of labeling synaptic vesicles have been proposed, and each method has its own characteristics, strength, and drawbacks. In this study, we introduce methods that can measure presynaptic activity and describe the characteristics of each technique.

Stability and drug release properties of liposomes containing cytarabine as a drug carrier

  • Kim, Chong-Kook;Park, Dong-Kyu
    • Archives of Pharmacal Research
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    • v.10 no.2
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    • pp.75-79
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    • 1987
  • Liposomes were studied as a drug delivery system. Multilamellar vesicles, small unilamellar vesicles and large unilamellar vesicles containing cytarabine were prepared using egg yolk lecithin and cholesterol. Large unilamellar vesicles showed the highest encapsulation efficiency of all and their encapsulation efficiency increased as the buffer volume decreased. Cholesterol increased the stability of liposomal drug products as drug carriers and reduced the permeability of drug across the liposomal membrane. The release rate of cytarabine increased with incubation temperature and decreased with cholesterol incorporation in liposomal membrane. The release mechanism of cytarabine from large unilamellar vesicles in vitro was chiefly due to simple diffusion across the liposomal membrane rather than liposomal rupture.

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Visualization of Extracellular Vesicles of Prokaryotes and Eukaryotic Microbes

  • Kim, Ki Woo
    • Applied Microscopy
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    • v.48 no.4
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    • pp.96-101
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    • 2018
  • The release of nanoscale membrane-bound vesicles is common in all three domains of life. These vesicles are involved in a variety of biological processes such as cell-to-cell communication, horizontal gene transfer, and substrate transport. Prokaryotes including bacteria and archaea release membrane vesicles (MVs) (20 to 400 nm in diameter) into their extracellular milieu. In spite of structural differences in cell envelope, both Gram-positive and negative bacteria produce MVs that contain the cell membrane of each bacterial species. Archaeal MVs characteristically show surface-layer encircling the vesicles. Filamentous fungi and yeasts as eukaryotic microbes produce bilayered exosomes that have varying electron density. Microbes also form intracellular vesicles and minicells that are similar to MVs and exosomes in shape. Electron and fluorescence microscopy could reveal the presence of DNA in MVs and exosomes. Given the biogenesis of extracellular vesicles from the donor cell, in situ high-resolution microscopy can provide insights on the structural mechanisms underlying the formation and release of microbial extracellular vesicles.

Comparative Study on the Transport Characteristics of Canalicular Liver Plasma Membrane Vesicles Prepared by Two Different Methods (제조 방법에 따른 간 모세담관막 소포계의 수송 특성 비교)

  • Song, Im-Sook;Chung, Suk-Jae;Shim, Chang-Koo
    • Journal of Pharmaceutical Investigation
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    • v.29 no.1
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    • pp.13-19
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    • 1999
  • Canalicular liver plasma membrane vesicles (cLPM) were prepared according to two different methods (Inoue method and Meier method), and were evaluated for their protein yield, enzyme activity and transport characteristics. No difference was found between the methods in the protein yield (i.e., $0.14{\pm}0.031$ and $0.15{\pm}0.050$ mglg liver for Inoue method and Meier method, respectively). The activity of alkaline phosphatase, a marker enzyme of canalicular membrane, was significantly (P<0.05) higher in the vesicles of Meier method $(3.52{\pm}0.91\;mmol/mg/hr)$than in the vesicles of Inoue method ($2.28{\pm}0.94$ mmol/mg/hr) indicating that more purified cLPM were obtained from Meier method compared with Inoue method. ATP-dependent vesicular uptake of taurocholate and tributylmethylammonium (TBuMA) was observed for vesicles of both methods, and the kinetic parameters responsible for the transport were similar between the vesicles of both methods (for example, $V_{max}:$ 9.72 nmol/mg protein/30sec and $K_m:$ 0.63 mM for Inoue method; $V_{max}:$ 10.1 nmol/mg protein/30sec and $K_m:$ 0.70 mM for Meier method). A pH gradient dependent counter transport of TBuMA was also observed for both vesicles with similar kinetic characteristics. Either the uptake of taurocholate in the absence of ATP or that of TBuMA in the absence of pH gradient, which may represent passive diffusion of respective compound into the vesicles, was more rapid for the vesicles of Meier method than for the vesicles of Inoue method. For example, passive diffusion rate constants $(K_d)$ for TBuMA uptake into the vesicles were 0.00030 and 0.00052\;{\mu}l/mg$ protein/min for the vesicles of Inoue method and Meier method, respectively. It may indicate that more leaky vesicles are obtained form the Meier method compared with the Inoue method. These aspects together with the time necessary to prepare the vesicles (i.e., 8 hr for Inoue method and 23 hr for Meier method) should be considered before selecting an appropriate method for the preparation of cLPM.

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Increase in $Na^+-Ca^{2+}$ Exchange Activity in Sarcolemma Isolated from Mesenteric Arteries of Spontaneously Hypertensive Rats

  • Lee, Shin-Woong;Lee, Jeung-Soo;Park, Young-Joo;Park, In-Sook
    • Archives of Pharmacal Research
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    • v.12 no.2
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    • pp.128-134
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    • 1989
  • $Na^+-Ca^{2+}$ exchange process in sarcolemmal vesicles isolated from mesenteric arteries of Wistar-Kyoto normotensive(WKY) and spontaneously hypertensive rats(SHR) was investigated. The sarcolemmal fractions isolated after homogenization and sucrose density gradient centrifugation were enriched with 5'-nucleotidase and ouabain sensitive, $K^+-dependent$ phosphatase activities. When the vesicles were loaded with $Na^+$, a time dependent $Ca^{2+}$ uptake was observed. However, very little $Ca^{2+}$ uptake was observed when the vesicles were loaded with $K^+$, or $Ca^{2+}$ uptake of the $Na^+-loaded$ vesicles was carried out in high sodium medium so that there was no sodium gradient. When the vesicles loaded with $Ca^{2+}$ by $Na^+-Ca^{2+}$ exchange were diluted into potassium medium containing EGTA, $Ca^{2+}$ was rapidly released from the vesicles. $Na^+-dependent\;Ca^{2+}$ uptake was increased in SHR compared to WKY, but passive efflux of preaccumulated $Ca^{2+}$ from the vesicles was decreased in SHR. The data indicate that the membrane vesicles of rat mesenteric arteries exhibit $Na^+-Ca^{2+}$ exchange activity. It is also suggested that changes of this process in vascular smooth muscle cell membrane of SHR may be involved in higher intracellular $Ca^{2+}$ concentration and higher basal tone in SHR.

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Role of Gel to Fluid Transition Temperatures of Polydiacetylene Vesicles with 10,12-Pentacosadiynoic Acid and Cholesterol in Their Thermochromisms

  • Kwon, Jun Han;Song, Ji Eun;Yoon, Bora;Kim, Jong Man;Cho, Eun Chul
    • Bulletin of the Korean Chemical Society
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    • v.35 no.6
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    • pp.1809-1816
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    • 2014
  • This study demonstrates gel-to-fluid transition temperatures of polydiacetylene bilayer vesicles could play important roles in their colorimetric transition temperatures. We prepared five types of polydiaceylene vesicles with 10,12-pentacosadiynoic acid (PCDA) and cholesterol (0-40 mol % of total content). From temperature-dependent observations of the optical signals (colors and UV-vis spectra), the blue-to-red colorimetric transition temperatures of polydiacetylene vesicles were decreased with the cholesterol contents. A further study with microcalorimetry and dynamic light scattering revealed that the polydiacetylene vesicles first underwent gel-to-fluid transitions, which were followed by event(s) responsible for the colorimetric transitions. Energies required for each event were quantified from analysis of the peaks in the microcalorimetry thermograms. The inclusion of cholesterol in the vesicles decreased both the gel-to-fluid and the colorimetric transition temperatures, suggesting that the colorimetric transition of the polydiacetylene vesicles was mediated by the former event although the event was not the direct reason for the color change.

Extracellular vesicles as emerging intercellular communicasomes

  • Yoon, Yae Jin;Kim, Oh Youn;Gho, Yong Song
    • BMB Reports
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    • v.47 no.10
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    • pp.531-539
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    • 2014
  • All living cells release extracellular vesicles having pleiotropic functions in intercellular communication. Mammalian extracellular vesicles, also known as exosomes and microvesicles, are spherical bilayered proteolipids composed of various bioactive molecules, including RNAs, DNAs, proteins, and lipids. Extracellular vesicles directly and indirectly control a diverse range of biological processes by transferring membrane proteins, signaling molecules, mRNAs, and miRNAs, and activating receptors of recipient cells. The active interaction of extracellular vesicles with other cells regulates various physiological and pathological conditions, including cancer, infectious diseases, and neurodegenerative disorders. Recent developments in high-throughput proteomics, transcriptomics, and lipidomics tools have provided ample data on the common and specific components of various types of extracellular vesicles. These studies may contribute to the understanding of the molecular mechanism involved in vesicular cargo sorting and the biogenesis of extracellular vesicles, and, further, to the identification of disease-specific biomarkers. This review focuses on the components, functions, and therapeutic and diagnostic potential of extracellular vesicles under various pathophysiological conditions.

Effect of Vesicle Curvature on Phospholipase D Reaction-Induced-Rupture

  • Lee, Gil Sun;Park, Jin-Won
    • Bulletin of the Korean Chemical Society
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    • v.34 no.11
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    • pp.3223-3226
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    • 2013
  • Spherical phospholipid-bilayers, vesicles, were prepared using the layer-by-layer double emulsion technique, which allows the bilayer to be formed asymmetrically. On the outer layer of the vesicles, the phospholipase D (PLD) reacted to convert phosphatidylcholine (PC) to phosphatidic acid (PA). The reaction induced the curvature change of the vesicles, which eventually led to rupture. The response time from the time of PLD injection to the time of rupture was measured against different vesicle curvatures and the outer layer phase, using the fluorescence intensity change of a pH-sensitive dye encapsulated within the vesicles. The effect of the vesicle curvature on the response was observed to be more significantly dramatic at the solid phase, compared to the liquid phase. Furthermore, in the solid phase, the response time was faster for 80 and 155 nm vesicles and, slower for 605 nm vesicles than similarly sized vesicles in the liquid phase vesicles. This difference in the response time was thought to result from the configuration determined by the phase difference and the PLD behavior.

Histochemical Study of Secretory Lipids by Imidazole Staining (Imidazole 염색에 의한 분비지질의 조직화학적 연구)

  • Kim, Eun-Soo;Mahlberg, Paul G.
    • Applied Microscopy
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    • v.30 no.2
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    • pp.113-119
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    • 2000
  • Lipophilic glandular trichomes form secretory vesicles that accumulate in a distended noncellular secretory cavity . Imidazole-buffered osmium tetroxide solution was used to visualize unsaturated lipids in glands of Cannabis sativa. This method of staining revealed two kinds of secretory vesicles in the cavity of glands. Some smaller and rounded vesicles in the secretory cavity and secretory cells were positively stained with the imidazole, and they appeared electron-dense. The other type of vesicles which have bigger sizes more or less were not reacted, however, they appeared transparent. A high contrast of the cuticles which cover the gland was also strongly reacted with that processing. Those result suggest that the dark vesicles in the cavity may contribute to enlarge the subcuticular wall and cuticle when contents of these vesicles are dispersed into wall.

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