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1.
Sci Rep ; 9(1): 14214, 2019 10 02.
Article in English | MEDLINE | ID: mdl-31578385

ABSTRACT

Searching for factors that reduce zearalenone (ZEN) toxicity is an important challenge in wheat production, considering that this crop is a basic dietary ingredient. ZEN, absorbed by cells, is metabolized into α-zearalenol and α-zearalanol, and this study focused on the function of manganese ions as potential protectants against the mycotoxins. Stress effects were invoked by an application of 30 µM ZEN and its derivatives. Manganese ions were applied at 100 µM, not stress-inducing concentration. Importance of the biomembrane structures in the absorption of the mycotoxins was demonstrated in in vitro wheat calli and on model membranes. ZEN showed the greatest and α-zearalanol the smallest stressogenic effect manifested as a decrease in the calli growth. This was confirmed by variable increase in antioxidant enzyme activity. Mn ions added to the toxin mixture diminished stressogenic properties of the toxins. Variable decrease in total lipid content and the percentage of phospholipid fraction detected in calli cells exposed to ZEN and its metabolites indicated significance of the membrane structure. An analysis of physicochemical parameters of model membranes build from phosphatidylcholine, a basic lipid in native membranes, and its mixture with the tested toxins made by Langmuir technique and verified by Brewster angle microscopy, confirmed variable contribution of ZEN and its derivatives to the modification of membrane properties. The order of toxicity was as follows: ZEN ≥ α-zearalenol > α-zearalanol. Manganese ions present in the hydrophilic phase interacted with polar lipid groups and reduced the extent of membrane modification caused by the mycotoxins.


Subject(s)
Chlorides/pharmacology , Manganese Compounds/pharmacology , Triticum/microbiology , Zearalenone/toxicity , 1,2-Dipalmitoylphosphatidylcholine/analogs & derivatives , Ascorbate Peroxidases/metabolism , Catalase/metabolism , Cell Membrane/drug effects , Cells, Cultured , Membrane Lipids/metabolism , Molecular Structure , Peroxidases/metabolism , Phosphatidylcholines , Plant Proteins/metabolism , Superoxide Dismutase/metabolism , Thermodynamics , Triticum/drug effects , Triticum/metabolism , Zearalenone/chemistry , Zearalenone/pharmacokinetics , Zeranol/analogs & derivatives , Zeranol/chemistry , Zeranol/metabolism , Zeranol/toxicity
2.
J Membr Biol ; 250(3): 273-284, 2017 06.
Article in English | MEDLINE | ID: mdl-28451712

ABSTRACT

The impact of zearalenone and selenate ions on the monolayers of 1,2-dipalmitoyl-phosphatidylcholine (DPPC), 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP), and the lipid mixtures (phospholipids and galactolipids) extracted from wheat plasmalemma has been studied using Langmuir trough technique and Brewster angle microscopy (BAM). The zearalenone is a mycotoxin that exerts toxic effects on the cells of plants and animals. Monolayers' properties were characterized by surface pressure (π)-molecular area (A) isotherms. It was found that zearalenone interacts with lipid monolayers causing their expansion. The selenate ions, added to the subphase together with zearalenone, reduce the effect of this mycotoxin on the surface properties of lipid films.


Subject(s)
Membranes, Artificial , Phospholipids/chemistry , Propane/analogs & derivatives , Quaternary Ammonium Compounds/chemistry , Selenium/chemistry , Zearalenone/chemistry , 1,2-Dipalmitoylphosphatidylcholine/chemistry , Animals , Propane/chemistry
3.
Colloids Surf B Biointerfaces ; 135: 133-142, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-26253533

ABSTRACT

Ultrathin "one-component" multilayer polymeric films for potential biomedical applications were designed based on polyvinyl alcohol,-a non-toxic, fully degradable synthetic polymer. Good uniformity of the obtained film and adequate adsorption properties of the polymeric layers were achieved by functional modification of the polymer, which involved synthesis of cationic and anionic derivatives. Synthesized polymers were characterized by FTIR, NMR spectroscopy, dynamic light scattering measurements and elemental analysis. The layer by layer assembly technique was used to build up a multilayer film and this process was followed using UV-Vis spectroscopy and ellipsometry. The morphology and thickness of the obtained multilayered film material was evaluated by atomic force microscopy (AFM). Preliminary studies on the application of the obtained multilayer film for coating of liposomal nanocarriers containing phenytoin, an antiarrhythmic drug, were performed. The coating effectively stabilizes liposomes and the effect increases with an increasing number of deposited layers until the polymeric film reaches the optimal thickness. The obtained release profiles suggest that bilayer-coated liposomes release phenytoin less rapidly than uncoated ones. The cytotoxicity studies performed for all obtained nanocarriers confirmed that none of them has negative effect on cell viability. All of the performed experiments suggest that liposomes coated with ultrathin film obtained from PVA derivatives can be attractive drug nanocarriers.


Subject(s)
Anti-Arrhythmia Agents/administration & dosage , Phenytoin/administration & dosage , Polyvinyl Alcohol/chemistry , Adult , Anti-Arrhythmia Agents/chemistry , Anti-Arrhythmia Agents/toxicity , Cell Survival/drug effects , Delayed-Action Preparations , Drug Carriers , Drug Delivery Systems , Fibroblasts/drug effects , Fibroblasts/metabolism , Humans , Liposomes , Microscopy, Atomic Force , Phenytoin/chemistry , Phenytoin/toxicity , Solubility
4.
Colloids Surf B Biointerfaces ; 112: 171-6, 2013 Dec 01.
Article in English | MEDLINE | ID: mdl-23973675

ABSTRACT

The influence of temperature on membrane-prazosin interactions was studied. Prazosin, a quinazoline derivative of 2-furoylpiperazine, is a classic antihypertensive and antiarrhythmic drug. A mixed cholesterol/phospholipid monolayer at the water/air interface was employed as a simplified biomembrane model. Brewster angle microscopy (BAM) was used to visualize the monolayer morphology. It was found that prazosin penetrates Langmuir monolayers and modifies the interactions between membrane components, causing monolayer fluidization. An increase in temperature facilitates penetration of prazosin into the monolayers. Prazosin interacts preferentially with phosphatidylcholine and modifies the morphology of the condensed phase domains of DPPC. In the presence of prazosin, monolayers collapse at lower surface pressures. The difference between the collapse pressures of monolayers on water with and without prazosin increases with temperature.


Subject(s)
Membrane Lipids/chemistry , Membranes, Artificial , Prazosin/chemistry , 1,2-Dipalmitoylphosphatidylcholine/chemistry , Blood-Brain Barrier , Cholesterol/chemistry , Diffusion , Membrane Fluidity , Prazosin/pharmacokinetics , Pressure , Surface Properties , Temperature
5.
Colloids Surf B Biointerfaces ; 109: 307-16, 2013 Sep 01.
Article in English | MEDLINE | ID: mdl-23668985

ABSTRACT

Stable vesicles for efficient curcumin encapsulation, delivery and controlled release have been obtained by coating of liposomes with thin layer of newly synthesized chitosan derivatives. Three different derivatives of chitosan were obtained and studied: the cationic (by introduction of the stable, quaternary ammonium groups), the hydrophobic (by attachment of N-dodecyl groups) and cationic-hydrophobic one (containing both quaternary ammonium and N-dodecyl groups). Zeta potential measurements confirmed effective coating of liposomes with all these chitosan derivatives. The liposomes coated with cationic-hydrophobic chitosan derivative are the most promising curcumin carriers; they can easily penetrate cell membrane and release curcumin in a controlled manner. Biological studies indicated that such systems are non-toxic for murine fibroblasts (NIH3T3) while toxic toward murine melanoma (B16F10) cell line.


Subject(s)
Antineoplastic Agents/pharmacology , Chitosan/analogs & derivatives , Chitosan/chemistry , Curcumin/pharmacology , Liposomes/chemistry , Animals , Antineoplastic Agents/toxicity , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Curcumin/toxicity , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Hydrophobic and Hydrophilic Interactions , Mice , NIH 3T3 Cells , Particle Size , Structure-Activity Relationship , Surface Properties
6.
Bioelectrochemistry ; 87: 42-9, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22357360

ABSTRACT

This paper describes the influence of interactions of poly(ethylene oxide) (PEO) with cationic cetyltrimethylammonium bromide (CTAB) micelles on drag reduction. Since the interactions between PEO and CTAB micelles alone are weak, salicylate ions were used as CTAB counterions. They facilitate formation of polymer-micelle aggregates by screening the electrostatic repulsions between the charged surfactant headgroups. The influence of polymer-surfactant interactions on drag reduction is of biomedical engineering importance. Drag reducing additives introduced to blood produce beneficial effects on blood circulation, representing a novel way to treat cardiovascular disorders. PEO is a blood-compatible polymer. However, it quickly mechanically degrades when subjected to high shear stresses. Thus, there is a need to search for other additives able to reduce drag, which would be more mechanically stable, e.g. polymer-surfactant aggregates. Numerical simulations of the flow were performed using the CFX software. Based on the internal structure of the polymer-surfactant solution, a hypothesis explaining the reason of increase of drag reduction and decrease in dynamic viscosity with increasing shear rate was proposed. It was suggested that the probable reason for the abrupt increase in friction factor, observed when the critical Reynolds number was exceeded, was the disappearance of the difference in the dynamic viscosity.


Subject(s)
Cetrimonium Compounds/chemistry , Polyethylene Glycols/chemistry , Software , Surface-Active Agents/chemistry , Cations , Cetrimonium , Computer Simulation , Micelles , Models, Chemical , Rheology , Salicylates/chemistry , Static Electricity , Viscosity , Water
7.
Bioelectrochemistry ; 87: 96-103, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22260980

ABSTRACT

In this study, the effect of prazosin on the molecular interactions between cholesterol and 1,2-dipalmitoylphosphatidylcholine (DPPC) within a monolayer at an air-water interface was studied. A mixed cholesterol/DPPC monolayer was employed as a model lipid membrane. From a detailed analysis of surface pressure-area isotherms, it was concluded that DPPC and cholesterol were miscible and formed non-ideal monolayers on prazosin solution. The thermodynamic stability of the mixed monolayers was investigated by analyzing the free energy of mixing. It was found that the mixed monolayers were more stable than the single component monolayers. Monolayers spread over a subphase with prazosin were more compressible than those spread on pure water. To quantify the effect of prazosin on the monolayer stability, the Gibbs free energy due to the presence of prazosin in the water subphase was calculated. It was found that prazosin penetrated and destabilized mixed cholesterol/DPPC monolayers. However, a comparison of the drug penetration into the pure DPPC monolayer and the mixed cholesterol/DPPC monolayer showed that the presence of cholesterol in the DPPC monolayer considerably restricted the drug penetration.


Subject(s)
1,2-Dipalmitoylphosphatidylcholine/chemistry , Adrenergic alpha-1 Receptor Antagonists/chemistry , Cholesterol/chemistry , Prazosin/chemistry , Air , Hydrogen Bonding , Membranes, Artificial , Models, Chemical , Surface Properties , Thermodynamics , Water
8.
Colloids Surf B Biointerfaces ; 88(1): 231-9, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21778041

ABSTRACT

Curcumin shows huge potential as an anticancer and anti-inflammatory agent. However, to achieve a satisfactory bioavailability and stability of this compound, its liposomal form is preferable. Our detailed studies on the curcumin interaction with lipid membranes are aimed to obtain better understanding of the mechanism and eventually to improve the efficiency of curcumin delivery to cells. Egg yolk phosphatidylcholine (EYPC) one-component monolayers and bilayers, as well as mixed systems containing additionally dihexadecyl phosphate (DHP) and cholesterol, were studied. Curcumin binding constant to EYPC liposomes was determined based on two different methods: UV/Vis absorption and fluorescence measurements to be 4.26×10(4)M(-1) and 3.79×10(4)M(-1), respectively. The fluorescence quenching experiment revealed that curcumin locates in the hydrophobic region of EYPC liposomal bilayer. It was shown that curcumin impacts the size and stability of the liposomal carriers significantly. Loaded into the EYPC/DPH/cholesterol liposomal bilayer curcumin stabilizes the system proportionally to its content, while the EYPC/DPH system is destabilized upon drug loading. The three-component lipid composition of the liposome seems to be the most promising system for curcumin delivery. An interaction of free and liposomal curcumin with EYPC and mixed monolayers was also studied using Langmuir balance measurements. Monolayer systems were treated as a simple model of cell membrane. Condensing effect of curcumin on EYPC and EYPC/DHP monolayers and loosening influence on EYPC/DHP/chol ones were observed. It was also demonstrated that curcumin-loaded EYPC liposomes are more stable upon interaction with the model lipid membrane than the unloaded ones.


Subject(s)
Curcumin/chemistry , Lipid Bilayers/chemistry , Liposomes/chemistry , Cholesterol/chemistry , Egg Yolk/chemistry , Phosphatidylcholines/chemistry , Spectrometry, Fluorescence
9.
Langmuir ; 27(17): 10886-93, 2011 Sep 06.
Article in English | MEDLINE | ID: mdl-21774543

ABSTRACT

The interactions of mixed monolayers of two lipids, zwitterionic 1,2-dipalmitoyl-phosphatidylcholine (DPPC) and positively charged 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP), with phytohormone indolilo-3-acetic acid (IAA) and selenate anions in the aqueous subphase were studied. For this purpose, isotherms of the surface pressure versus the mean molecular area were recorded. Domain formation was investigated by using Brewster angle microscopy (BAM). The method of grazing incidence X-ray diffraction (GIXD) was also applied for the characterization of the organization of lipid molecules in condensed monolayers. It was found that selenate ions contribute to monolayer condensation by neutralizing the positive net charge of mixed monolayers whereas IAA molecules penetrated the lipid monolayer, causing its expansion/fluidization. When both solutes were introduced into the subphase, a competition between them for interaction with the positively charged lipids in the monolayer was observed.


Subject(s)
1,2-Dipalmitoylphosphatidylcholine/chemistry , Acetates/chemistry , Indoles/chemistry , Membranes, Artificial , Propane/analogs & derivatives , Quaternary Ammonium Compounds/chemistry , Selenium Compounds/chemistry , Air , Ions/chemistry , Propane/chemistry , Selenic Acid , Water/chemistry
10.
Chem Phys Lipids ; 163(1): 74-81, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19909732

ABSTRACT

The behaviour of equimolar mixtures of alpha-tocopherol with monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) and phospholipids (PL) isolated from wheat calli cultured on media with and without cadmium was investigated at the air-water interface by surface pressure-area (pi-A) measurements established using an automated Langmuir-type film balance. It was found that monolayers of all studied compounds were expanded. The additivity rule was not fulfilled and the collapse pressure of mixtures was different from these recorded for pure components. This can be related with the existence of interactions between molecules in mixed monolayers. Tocopherol diminished the differences between parameters of monolayers formed by lipids extracted from objects cultivated on various media (with and without cadmium).


Subject(s)
Cadmium/toxicity , Lipids/chemistry , Plastids/drug effects , Triticum/drug effects , Vitamin E/pharmacology , Galactolipids/chemistry , Phospholipids/chemistry , Plastids/chemistry , Surface Properties , Thermodynamics , Vitamin E/chemistry
11.
J Plant Physiol ; 167(1): 28-33, 2010 Jan 01.
Article in English | MEDLINE | ID: mdl-19682767

ABSTRACT

Selenium appears to be an important protective agent that decreases cadmium-induced toxic effects in animals and plants. The aim of these studies was to investigate the changes of properties of chloroplast membranes obtained from Cd-treated rape seedlings caused by Se additions. Chloroplasts were isolated from leaves of 3-week-old rape plants cultured on Murashige-Skoog media supplied with 2 microM Na(2)SeO(4) and/or 400 microM CdCl(2) under in vitro conditions. The following physicochemical characteristics of chloroplasts were chosen as indicators of Se-effects: average size, zeta potential, ultrastructure, lipid and fatty acid composition and fluidity of envelope membrane. The results suggest that Se can partly counterbalance the destructive effects of Cd. This protective action led to an increase of chloroplast size reduced by Cd treatment and rebuilt, to some extent, the chloroplast ultrastructure. Lipid and fatty acid composition of chloroplast envelopes modified by Cd showed a decrease in digalactosyl-diacylglycerol content and an increase of content of monogalactosyl-diacylglycerol and phospholipid fractions, as well as an increase of fatty acid saturation of all lipids studied. The change in fatty acid saturation correlated well with a decrease of membrane fluidity and with a diminishing of absolute values of zeta potential. The presence of selenium in cultured media caused a partial reversal of the detected changes, which was especially visible in properties related to the hydrophobic part of an envelope, i.e. fatty acid saturation and fluidity.


Subject(s)
Brassica napus/drug effects , Brassica napus/physiology , Cadmium/toxicity , Chloroplasts/drug effects , Chloroplasts/physiology , Selenium/pharmacology , Brassica napus/growth & development , Brassica napus/ultrastructure , Chloroplasts/ultrastructure , Culture Media/pharmacology , Fatty Acids/analysis , Fluorescence Polarization , Light , Organelle Size/drug effects , Plant Leaves/drug effects , Plant Leaves/growth & development , Plant Leaves/ultrastructure , Scattering, Small Angle , X-Ray Diffraction
12.
Langmuir ; 25(22): 13071-6, 2009 Nov 17.
Article in English | MEDLINE | ID: mdl-19831406

ABSTRACT

In this study, the influence of plant hormones, negatively charged indolilo-3-acetic acid (IAA) and positively charged zeatin, on lipid membranes was studied. As models of negatively and positively charged biological membranes, monolayers of 1,2-dimyristoyl-sn-glycero-3-[phospho-l-serine] (DMPS) and 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP) at the water/air interface were used, respectively. Additionally, the effect of cadmium and selenium ions on the interactions between hormones and lipids was studied. Surface pressure and surface potential measurements, Brewster angle microscopy (BAM), and grazing incidence X-ray diffraction (GIXD) were used for that purpose. Both IAA and zeatin led to an expansion of the lipid monolayer caused by electrostatic interactions between oppositely charged groups: negatively charged polar group of DMPS and positively charged zeatin or positive DPTAP headgroup and negative IAA. The addition of ions to the subphase containing hormones causes competitive interactions of both solutes with oppositely charged lipid polar heads. The largest effect was observed for IAA. While zeatin does not change the domain shape of DMPS, IAA causes the complete disappearance of characteristic DPTAP domains. Addition of SeO(4)(2-) ions causes restoration of DPTAP domains observed on pure water.


Subject(s)
Cadmium/chemistry , Hormones/chemistry , Indoleacetic Acids/chemistry , Selenium Compounds/chemistry , Membranes, Artificial , Propane/analogs & derivatives , Propane/chemistry , Quaternary Ammonium Compounds/chemistry , Selenic Acid , Unithiol/chemistry , X-Ray Diffraction , Zeatin/chemistry
13.
Chem Phys Lipids ; 155(1): 24-30, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18639537

ABSTRACT

The aim of presented researches was to investigate the physicochemical properties of Langmuir monolayer of galactolipids extracted from two different kinds of plastids: immature embryos and inflorescences. Differences between the physicochemical properties of the plastid membranes may help to explain different physiological processes, such as plant regeneration. Surface pressure (pi) vs. molecular area (A) isotherms of the monogalactosyldiacylglycerol (MGDG)/digalactosyldiacylglycerol (DGDG) monolayers of various molar ratios were measured at 15 degrees C. Galactolipids were extracted from two different types of tissue: inflorescences and embryos. Based on the analysis of the pi-A isotherms, the properties of monolayers, such as collapse pressure (pi(coll)), limiting area (A(lim)), compressibility modulus (C(s)(-1)), excess free energy of mixing (DeltaG(EXC)) and free energy of mixing (DeltaG(MIX)), were calculated. The results show that pure MGDG and DGDG and their mixtures form liquid-expanded monolayers, independently on the kind of tissue. Galactolipids originating from inflorescences produce more compressible films at the air/water interface, with larger limiting area per molecule and lower stability against the collapse process. MGDG and DGDG are miscible and form non-ideal mixed monolayers at the air/water interface. Negative values of DeltaG(EXC) were calculated for the mixture of galactolipids originating from inflorescences, with the content of MGDG, x(MGDG)>0.6. In the case of embryos, the negative values of DeltaG(EXC) were found for x(MGDG) approximately 0.5. Therefore, the attractive interactions between MGDG and DGDG exist in the mixtures of these compositions. As it is shown by negative values of DeltaG(MIX), mixed monolayers are more stable compared with unmixed ones.


Subject(s)
Galactolipids/chemistry , Triticum/metabolism , Air , Cell Culture Techniques/methods , Cell Membrane/metabolism , Chemistry, Physical/methods , Plant Physiological Phenomena , Plants/metabolism , Plastids/metabolism , Surface Properties , Temperature , Thermodynamics , Water/chemistry
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