Changes Caused by Fruit Extracts in the Lipid Phase of Biological and Model Membranes

The aim of the study was to determine changes incurred by polyphenolic compounds from selected fruits in the lipid phase of the erythrocyte membrane, in liposomes formed of erythrocyte lipids and phosphatidylcholine liposomes. In particular, the effect of extracts from apple, chokeberry, and strawberry on the red blood cell morphology, on packing order in the lipid hydrophilic phase, on fluidity of the hydrophobic phase, as well as on the temperature of phase transition in DPPC liposomes was studied. In the erythrocyte population, the proportions of echinocytes increased due to incorporation of polyphenolic compounds. Fluorimetry with a laurdan probe indicated increased packing density in the hydrophilic phase of the membrane in presence of polyphenolic extracts, the highest effect being observed for the apple extract. Using the fluorescence probes DPH and TMA-DPH, no effect was noted inside the hydrophobic phase of the membrane, as the lipid bilayer fluidity was not modified. The polyphenolic extracts slightly lowered the phase transition temperature of phosphatidylcholine liposomes. The studies have shown that the phenolic compounds contained in the extracts incorporate into the outer region of the erythrocyte membrane, affecting its shape and lipid packing order, which is reflected in the increasing number of echinocytes. The compounds also penetrate the outer part of the external lipid layer of liposomes formed of natural and DPPC lipids, changing its packing order

Possibilities of nanodiamonds application – biological and medical aspects

This topical review briefly discusses selected highlights of research on diamond nanoparticles obtained by different methods and their potential applications in biology and medicine. In recent years nanotechnology has aroused interest of large number of scientists who endeavor to obtain nanoparticles (which differ in size and structure of surface) using different methods, in order to determine their physical, chemical and biological properties that are in relation to the methods used in the process of their production. The knowledge developed in this way will be beneficial in an attempt to use nanoparticles more reasonably in various branches of science. The distinguishing features of carbon nanoparticles are their biocompatibility, photostability and easily chemically modified surface that result in high usefulness for intarcellular studies. What is more, low toxicity of nanoparticles with many cell lines is at the center of scientific interest. This, in turn, leads to a large number of biomedical applications. The property that nanodiamonds are able to penetrate into cells through endocytosis, allows to deliver the drug connected with nanoparticles into cancer cells. These features of nanoparticles have given many promising leads in nanooncology, in particular in drug delivery, diagnosis, imaging and therapy. This paper presents a summary of different classes of nanodiamond particles, the ways of their uptake into cells, an overview of the possible application of nanoparticles as nanocarriers and as a clinical theranostic platform, as well as advantages and disadvantages of using nanodiamonds in biomedicine

In Vitro Studies of Anti-Hemolytic and Cytotoxic Activity of Procyanidin-Rich Extract from the Leaves of Actinidia arguta

The leaves of mini kiwi (Actinidia arguta) are a rich source of phenolic compounds, in particular the B-type procyanidins that exhibit e.g. antioxidant, anticancer, antiviral, and anti-inflammatory activities. The aim of this study was to determine the biological activity of the extract from leaves of kiwi in relation to cells of erythrocytes and lymphoma. This activity was determined by studying kiwi leaves extract anti-hemolytic, cytotoxic and antiproliferative activity, and its ability to change the physical properties of the cell membrane and inhibit multidrug resistance of mouse lymphoma cells. It was shown that the extract ingredients bound to the cells, caused changes in erythrocyte shape and slightly affected the granularity and size of lymphoma cells. They effectively protected the red blood cells from oxidative damage, but were not toxic to lymphoma cells and did not affect their multidrug resistance. The extract of kiwi leaves is an effective antioxidant but it does not exhibit cytotoxic activity. Therefore, it can be used in the prevention of diseases, especially those related to oxidative stress

The Impact of O-Glycosylation on Cyanidin Interaction with POPC Membranes: Structure-Activity Relationship

Cyanidin and its O-glycosides have many important physiological functions in plants and beneficial effects on human health. Their biological activity is not entirely clear and depends on the structure of the molecule, in particular, on the number and type of sugar substituents. Therefore, in this study the detailed structure-activity relationship (SARs) of the anthocyanins/anthocyanidins in relation to their interactions with lipid bilayer was determined. On the basis of their antioxidant activity and the changes induced by them in size and Zeta potential of lipid vesicles, and mobility and order of lipid acyl chains, the impact of the number and type of sugar substituents on the biological activity of the compounds was evaluated. The obtained results have shown, that 3-O-glycosylation changes the interaction of cyanidin with lipid bilayer entirely. The 3-O-glycosides containing a monosaccharide induces greater changes in physical properties of the lipid membrane than those containing disaccharides. The presence of additional sugar significantly reduces glycoside interaction with model lipid membrane. Furthermore, O-glycosylation alters the ability of cyanidin to scavenge free radicals. This alteration depends on the type of free radicals and the sensitivity of the method used for their determination

ALLIUM URSINUM L. LEAVES COMPONENTS MODIFIED THE PHYSICO-CHEMICAL PROPERTIES OF RED BLOOD CELLS PROTECTING THEM FROM THE EFFECTS OF OXIDATIVE STRESS

The aim of the study is to determine the antioxidant activity and influence of Allium ursinum L. leaf extract on physicochemical and electrical properties of erythrocytes in order to help clarify its capacity to alleviate oxidative stress. The phenolic compounds were isolated from the leaves of bear garlic. The composition of the extract is well documented and was earlier analyzed quantitatively and qualitatively by UPLC methods. The impact of the extract constituents on the erythrocyte membrane properties was determined on the basis of its osmotic fragility, fluidity, organization of the hydrophilic area and transmembrane potential with spectrophotometric and fluorimetric methods. Furthermore, the effect of the extract on the level of membrane lipid oxidation and also on the extent of hemolysis of erythrocytes subjected to oxidation induced by AAPH compound was determined. The study showed that the extract at 40 µg/mL lowers the level of erythrocyte hemolysis caused by 76.8% oxidation. In addition, the extract protects lipid membranes against hemolysis better than ascorbic acid. The extract, in examined range of concentrations, did not induce hemolysis of erythrocytes, caused small decrease in their electric potential and osmotic fragility, and increased disorder of the polar heads of membrane lipids. The high antioxidant efficiency and determined effects of the interaction of bear garlic leaf extract with the erythrocyte membrane suggest that its constituents may not only protect cells against free radicals but also mitigate the effects of oxidative stress

In Vitro Studies of Anti-Hemolytic and Cytotoxic Activity of Procyanidin-Rich Extract from the Leaves of Actinidia arguta

The leaves of mini kiwi (Actinidia arguta) are a rich source of phenolic compounds, in particular the B-type procyanidins that exhibit e.g. antioxidant, anticancer, antiviral, and anti-inflammatory activities. The aim of this study was to determine the biological activity of the extract from leaves of kiwi in relation to cells of erythrocytes and lymphoma. This activity was determined by studying kiwi leaves extract anti-hemolytic, cytotoxic and antiproliferative activity, and its ability to change the physical properties of the cell membrane and inhibit multidrug resistance of mouse lymphoma cells. It was shown that the extract ingredients bound to the cells, caused changes in erythrocyte shape and slightly affected the granularity and size of lymphoma cells. They effectively protected the red blood cells from oxidative damage, but were not toxic to lymphoma cells and did not affect their multidrug resistance. The extract of kiwi leaves is an effective antioxidant but it does not exhibit cytotoxic activity. Therefore, it can be used in the prevention of diseases, especially those related to oxidative stress

Influence of amphiphilic compounds on membranes.

On the basis of Gortel & Grendel (J. Exp. Med., 1925, 41, 439-494) discovery, the importance of the lipid bilayer as an integral and indispensible component of the cell membrane is discussed. In particular, attention focuses on the interaction between membranes and amphiphilic substances. The effect on membranes of quaternary ammonium salts, both in the form of pesticides and oxidants as well as organic compounds of tin and lead are discussed in greater detail