Development of egg PC/cholesterol/α-tocopherol liposomes with ionic gradients to deliver ropivacaine

Experimental results reveal that addition of P123 to the drug-bound egg-PC vesicles results in a preferential complexation of the drug with the Pluronic leaving the lipid vesicles aside which indicates a substantially stronger binding interaction of the drug with P123 than that with egg-PC.

Download Full-text

Adhesion process of egg PC vesicles on mica surface; studies by atomic force microscopy

Hydrocolloids ◽

10.1016/b978-044450178-3/50066-4 ◽

2000 ◽

pp. 51-56

Author(s):

K. Furusawa ◽

H. Egawa ◽

H. Terashima

Keyword(s):

Atomic Force Microscopy ◽

Mica Surface ◽

Surface Studies ◽

Force Microscopy ◽

Atomic Force ◽

Adhesion Process ◽

Egg Pc

Download Full-text

Effects of ionic liquids on membrane fusion and lipid aggregation of egg-PC liposomes

Colloids and Surfaces B Biointerfaces ◽

10.1016/j.colsurfb.2014.11.021 ◽

2015 ◽

Vol 125 ◽

pp. 142-150 ◽

Cited By ~ 21

Author(s):

Paola Galletti ◽

Danilo Malferrari ◽

Chiara Samorì ◽

Giorgio Sartor ◽

Emilio Tagliavini

Keyword(s):

Ionic Liquids ◽

Membrane Fusion ◽

Egg Pc

Download Full-text

Preparation and Characterization of Stealth Archaeosomes Based on a Synthetic PEGylated Archaeal Tetraether Lipid

Journal of Drug Delivery ◽

10.1155/2011/396068 ◽

2011 ◽

Vol 2011 ◽

pp. 1-11 ◽

Cited By ~ 19

Author(s):

Julie Barbeau ◽

Sandrine Cammas-Marion ◽

Pierrick Auvray ◽

Thierry Benvegnu

Keyword(s):

High Performance ◽

Drug Carriers ◽

Physicochemical Characteristics ◽

Release Studies ◽

Poly Ethylene ◽

Membrane Spanning ◽

The Stability ◽

The One ◽

Egg Pc

The present studies were focused on the formation and characterization of sterically stabilized archaeosomes made from a synthetic PEGylated archaeal lipid. In a first step, a synthetic archaeal tetraether bipolar lipid was functionalized with a poly(ethylene glycol), PEG, and (PEG45-Tetraether) with the aim of coating the archaeosome surface with a sterically stabilizing hydrophilic polymer. In a second step, Egg-PC/PEG45-Tetraether (90/10 wt%) archaeosomes were prepared, and their physicochemical characteristics were determined by dynamic light scattering (size, polydispersity), cryo-TEM (morphology), and by high-performance thin layer chromatography (lipid composition), in comparison with standard Egg-PC/PEG45-DSPE formulations. Further, a fluorescent dye, the carboxyfluorescein, was encapsulated into the prepared archaeosomes in order to evaluate the potential of such nanostructures as drug carriers. Release studies have shown that the stability of Egg-PC/PEG45-Tetraether-based archaeosomes is significantly higher at 37∘C than the one of Egg-PC/PEG45-DSPE-based liposomes, as evidenced by the slower release of the dye encapsulated into PEGylated archaeosomes. This enhanced stability could be related to the membrane spanning properties of the archaeal bipolar lipid as already described with natural or synthetic tetraether lipids.

Download Full-text

Thermodynamics of mixing of dipalmitoyl phosphatidylcholine and egg phosphatidylcholine in hydrated bilayers

Canadian Journal of Biochemistry ◽

10.1139/o82-066 ◽

1982 ◽

Vol 60 (5) ◽

pp. 538-548 ◽

Cited By ~ 2

Author(s):

David O. Tinker ◽

Rosita Low

Keyword(s):

Molar Volume ◽

Liquid Crystalline ◽

Binary Solution ◽

Empirical Relationship ◽

Mixing Enthalpy ◽

Aqueous Mixtures ◽

Scanning Calorimetry ◽

Dipalmitoyl Phosphatidylcholine ◽

Transition Enthalpy ◽

Egg Pc

Dipalmitoyl phosphatidylcholine (DPPC) and egg phosphatidylcholine (egg PC) are not completely miscible at all temperatures. Their phase diagram was determined by differential scanning calorimetry (DSC) of aqueous mixtures of the two. From the integrated DSC curves we obtained the enthalpy of solution of DPPC in egg PC, Δhs, as a function of the mole fraction of DPPC, X, and using the empirical relationship between Δhs and X, the solubility Xsat as a function of temperature, T. The latter could be described by the semiempirical relationship:RlnXsat = a + blnT – c/T, where a = 6.57 × 10−2 kcal∙mol−1∙degree−1 and c = 20.5 kcal∙mol−1 (1 cal = 4.1868 J); the coefficient b was very small and could be ignored. The quantity Δhs can be given as XΔhDPPC + Δhmix, where ΔhDPPC is the gel – liquid crystalline transition enthalpy of DPPC (8.74 kcal∙mol−1) and Δhmix is the enthalpy of mixing the two liquid crystalline lipids. Δhmix depends on X in approximately a parabolic fashion, having a maximal value of 4.8 kcal∙mol−1 at X = 0.6.It was shown that both the solubility and mixing enthalpy data can be described by the theory of regular solutions (RST). In RST, the activity coefficient of the solute (component 2) of a binary solution is given by RTlnγ2 = (1 − θ2)2ΔU, while the mixing enthalpy is given by Δhmix = θ1θ2 ΔU/v2, where θ1 and θ2 are the volume fractions of solvent and solute (egg PC and DPPC, respectively), v2 is the partial molar volume of DPPC, and ΔU is the energy change per mole on interchanging a DPPC and an egg PC molecule between their respective liquid crystalline phases. The thermodynamic data are accurately described by RST, the molar volume of DPPC being found to be about half mat of egg PC solution and the interchange energy ΔU having a value of 10–11 kcal∙mol−1. There was some evidence that ΔU may be an increasing function of temperature. The large value of the ΔU accounts for the pronounced temperature dependence of the solubility Xsat, which decreases from 0.35 at 35 °C to 0.02 at 10 °C.The presence of cholesterol in the mixtures decreases both the transition enthalpy of DPPC and the mixing enthalpy in a linear fashion, so that Δhs is zero at Xcholesterol ≥ 0.2. The results are consistent with recent data indicating the formation of a PC–cholesterol complex of stoichiometry approximately 4:1.

Download Full-text

A High-Fat Diet Containing 50% Egg-Phosphatidylcholine Increased the Proportion of T Cells Expressing a Memory Marker in Male Wistar Rats

Current Developments in Nutrition ◽

10.1093/cdn/nzab061_024 ◽

2021 ◽

Vol 5 (Supplement_2) ◽

pp. 1140-1140

Author(s):

Tianna Rusnak ◽

Jessy Azarcoya Barrera ◽

Bethany Wollin ◽

Anna Thomsen ◽

Alexander Makarowski ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

High Fat Diet ◽

Wistar Rats ◽

Dose Effect ◽

Helper T Cells ◽

High Fat ◽

Low Fat ◽

Male Wistar Rats ◽

Egg Pc

Abstract Objectives Studies have suggested that high-fat (HF) diets are associated with immune dysfunction, which results in a lower production of IL-2 and a lower proportion of helper T cells. Providing a diet containing 100% phosphatidylcholine (PC), a form of choline mainly found in eggs, has been shown to increase IL-2 production early in life. However, this is of no relevance for human consumption since no human diet will contain 100% PC. Therefore, the objective of this study was to determine the dose effect of egg-PC added to a high fat diet compared to a control high fat and low fat diets on T cell function in male Wistar rats. Methods At four weeks of age, male Wistar rats were randomized to consume one of 6 diets: 1- Control low fat (CLF, 10%wt/wt fat, 100% free choline (FC), n = 10); 2- Control high fat (CHF, 25% wt/wt fat, 100% FC, n = 10); 3- 100% PCHF (100PCHF, 25% wt/wt fat, 100% PC, n = 10); 4- 75% PCHF (75PCHF, 25% wt/wt fat, 75% PC, 25% FC, n = 10); 5- 50% PCHF (50PCHF, 25% wt/wt fat, 50% PC, 50% FC, n = 10); 6- 25% PCHF (25PCHF; 25% wt/wt fat, 25% PC, 75% FC, n = 10). Fatty acid composition was closely matched in all of the diets. Anthropometric data was collected through the duration of the study (12 weeks). At the end of the study, splenocytes phenotypes were measured by flow cytometry. Results From week 1 to week 10 there was no difference in body weight between the diets. Starting from week 2 the CLF group had a higher food intake compared to the other groups. The 50PCHF diet had a higher proportion of helper T cells (CD4+) compared to the CLF and CHF diets. In addition, 50PCHF had a higher proportion of helper T cells expressing IL-2 receptors (CD4+CD25+) compared to 25PCHF (P < 0.05). 50PCHF also had a higher proportion of T cells expressing a memory marker (CD3+CD27+) compared with all HF diets (all P < 0.05) but not the CLF diet. Conclusions Our results suggest that a diet providing 50% of total choline in the form of egg-PC normalizes the proportion of T cells expressing CD27 in the context of a HF diet which may lead to a better immune response if a second exposure to a pathogen occurs. Whether the higher proportion of helper T cells expressing the IL-2 receptor in the 50PCHF group is associated with better T cell response upon challenge remains to be investigated. Funding Sources Egg farmers of Canada, NSERC.

Download Full-text

Phosphatidic acid regulates the activity of the channel-forming ionophores alamethicin, melittin, and nystatin: A1H-NMR study using phospholipid membranes

Bioscience Reports ◽

10.1007/bf01122505 ◽

1984 ◽

Vol 4 (5) ◽

pp. 403-413 ◽

Cited By ~ 11

Author(s):

G. R. A. Hunt ◽

I. C. Jones ◽

J. A. Veiro

Keyword(s):

Nmr Spectroscopy ◽

Phosphatidic Acid ◽

Active Metabolite ◽

Egg Yolk ◽

Phospholipid Vesicles ◽

Dipalmitoyl Phosphatidylcholine ◽

Egg Yolk Phosphatidylcholine ◽

Nmr Study ◽

The Individual ◽

Egg Pc

The regulation of ion channels by phosphatidic acid (a proposed active metabolite in the phosphatidylinositol effect) was investigated using1H-NMR spectroscopy and small unilamellar phospholipid vesicles. Transport across egg-yolk phosphatidylcholine (egg PC) and dipalmitoyl phosphatidylcholine (DPPC) vesicular membranes in the presence of the channel-forming ionophores alamethicin, melittin, and nystatin was monitored using the lanthanide probe ion Pr3+. In the absence of the ionophores, phosphatidic acid (PA) alone was found to have no ionophore properties, but in the presence of the ionophores the incorporation of 3 mol % phosphatidic acid in the bilayer markedly increased the rate of transport using melittin and nystatin, but decreased the rate using alamethicin, independent of the type of phosphatidylcholine used. The presence of PA in the bilayer also stimulated the production of lyric type channels, the extent of which were both ionophore- and lipid-dependent. These results are discussed in terms of possible molecular interactions between the PA, the individual ionophores, and type of lipid used.

Download Full-text

Dynamic structure of the lower density lipoproteins. II. Deuterium NMR studies of the monolayer of very low and low density lipoproteins

Biochemistry and Cell Biology ◽

10.1139/o90-025 ◽

1990 ◽

Vol 68 (1) ◽

pp. 189-198 ◽

Cited By ~ 8

Author(s):

Ravinder S. Chana ◽

W. Dale Treleaven ◽

Yashpal I. Parmar ◽

Robert J. Cushley

Keyword(s):

Acyl Chain ◽

Dynamic Structure ◽

Low Density Lipoproteins ◽

Deuterium Nmr ◽

Low Density ◽

Very Low Density Lipoproteins ◽

Nmr Studies ◽

Surface Domains ◽

Egg Pc ◽

Low Order

The order of phosphatidylcholine (PC) acyl chains in the surface monolayer of very low density lipoproteins (VLDL) and low density lipoproteins (LDL) has been determined from 2H nuclear magnetic resonance order parameters, SCD, using selectively deuterated PC or palmitic acids. From the computer simulated line shapes, we find two distinct phospholipid domains within the amphiphilic monolayer of both VLDL and LDL. In the more ordered domain of LDL, SCD was ≈ 0.3 for the "plateau" chain region. The SCD values of VLDL particles are similar to those of LDL for the 5,6- and 11,12-positions, hence we suggest the organization of the more ordered region of VLDL and LDL are similar. The domain of low order in LDL comprises < 10% of the phospholipid molecules (we do not distinguish between PC and sphingomyelin), having approximately the same order (SCD < 0.1) as egg PC - sphingomyelin unilamellar vesicles. In VLDL, the domain of low order comprises between ≈ 10 and ≈ 20% of the phospholipid molecules and the entire acyl chain is in an essentially isotropic environment (SCD < 0.02). We prepared VLDL-sized microemulsions composed of egg PC, deuterated PC, and triolein to test whether the apoproteins were responsible for creating the two differently organized domains in VLDL and LDL. Surprisingly, these protein-free particles also showed two domains of different order at two temperatures. The high order region, however, is less ordered than in VLDL and LDL. We explain two surface domains of PC in terms of lipid organization and the unique interactions of lipids in the various lipoprotein particles.Key words: lipoproteins, deuterium NMR, phospholipid organization, microemulsions, surface diffusion.

Download Full-text