scholarly journals Interaction of selected anthocyanins with erythrocytes and liposome membranes

2012 ◽  
Vol 17 (2) ◽  
Author(s):  
Dorota Bonarska-Kujawa ◽  
Hanna Pruchnik ◽  
Halina Kleszczyńska
Keyword(s):  
Phase Transition ◽  
Antioxidant Activity ◽  
Erythrocyte Membrane ◽  
Wide Spectrum ◽  
Outer Part ◽  
Outer Region ◽  
Fluorescence Probes ◽  
Lipid Phase ◽  
Egg Lecithin ◽  
Erythrocyte Lipids

AbstractAnthocyanins are one of the main flavonoid groups. They are responsible for, e.g., the color of plants and have antioxidant features and a wide spectrum of medical activity. The subject of the study was the following compounds that belong to the anthocyanins and which can be found, e.g., in strawberries and chokeberries: callistephin chloride (pelargonidin-3-O-glucoside chloride) and ideain chloride (cyanidin-3-O-galactoside chloride). The aim of the study was to determine the compounds’ antioxidant activity towards the erythrocyte membrane and changes incurred by the tested anthocyanins in the lipid phase of the erythrocyte membrane, in liposomes composed of erythrocyte lipids and in DPPC, DPPC/cholesterol and egg lecithin liposomes. In particular, we studied the effect of the two selected anthocyanins on 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 and DPPC/cholesterol liposomes. Fluorimetry with the Laurdan and Prodan probes indicated increased packing density in the hydrophilic phase of the membrane in the presence of anthocyanins. 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 compounds slightly lowered the phase transition temperature of phosphatidylcholine liposomes. The study has shown that both anthocyanins are incorporated 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 investigation proved that the compounds penetrate only the outer part of the external lipid layer of liposomes composed of erythrocyte lipids, DPPC, DPPC/cholesterol and egg lecithin lipids, changing its packing order. Fluorimetry studies with DPH-PA proved that the tested anthocyanins are very effective antioxidants. The antioxidant activity of the compounds was comparable with the activity of Trolox®.

Probing Ethanol-Induced Phospholipid Phase Transitions by the Polarity Sensitive Fluorescence Probes Prodan and Patman

2002 ◽  
Vol 216 (3) ◽  
Author(s):  
R. Hutterer ◽  
M. Hof
Keyword(s):  
Phase Transition ◽  
Emission Spectra ◽  
Fluorescence Probes ◽  
Lipid Phase ◽  
Time Resolved ◽  
Pronounced Increase ◽  
Spectral Shifts ◽  
Gel Phase ◽  
Polarity Sensitive ◽  
Specific Lipid

The emission behaviour of the two polarity sensitive probes Prodan and Patman in phospholipid vesicles was studied as a function of the concentration of ethanol. Comparing the spectral shifts in both the symmetric lipid 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) showing a phase transition from a normal to a fully interdigitated gel phase and the strongly asymmetric lipid 1-stearoyl-2-lauroyl-sn-glycero-3-phosphatidylcholine (C(18):C(12)-PC) favouring a mixed interdigitated gel phase we show that the huge red shifts of Prodan in presence of higher ethanol concentrations cannot be easily attributed to a specific lipid phase transition. Rather, probe relocation and a pronounced increase in solvent relaxation (SR) as monitored by time-resolved emission spectra (TRES) in presence of ethanol contribute to the large shifts observable in both lipid systems in case of Prodan. While Patman exhibits a red shift caused by increased SR due to the ethanol induced formation of a fully interdigitated phase in DPPC, hardly any shift occurs in C(18):C(12)-PC, which is supposed not to undergo an ethanol-induced phase transition.

Fatty acyl chain structure, orientational order, and the lipid phase transition in Acholeplasma laidlawii B membranes. A review of recent 19F nuclear magnetic resonance studies

1984 ◽  
Vol 62 (11) ◽  
pp. 1134-1150 ◽  
Author(s):  
P. M. Macdonald ◽  
B. D. Sykes ◽  
R. N. McElhaney
Keyword(s):  
Phase Transition ◽  
Fatty Acids ◽  
Nuclear Magnetic Resonance ◽  
Acyl Chain ◽  
Orientational Order ◽  
Membrane Lipid ◽  
Fatty Acyl ◽  
Fatty Acyl Chain ◽  
Lipid Phase ◽  
Lipid Phase Transition

The orientational order parameters of monofluoropalmitic acids biosynthetically incorporated into membranes of Acholeplasma laidlawii B in the presence of a large excess of a variety of structurally diverse fatty acids have been determined via 19F nuclear magnetic resonance (19F NMR) spectroscopy. It is demonstrated that these monofluoropalmitic acids are relatively nonperturbing membrane probes based upon physical (differential scanning calorimetry), biochemical (membrane lipid analysis), and biological (growth studies) criteria. 19F NMR is shown to convey the same qualitative and quantitative picture of membrane lipid order provided by 2H-NMR techniques and to be sensitive to the structural characteristics of the membrane fatty acyl chains, as well as to the lipid phase transition. Representatives of each naturally occurring class of fatty acyl chain structures, including straight-chain saturated, methyl-branched, monounsaturated, and alicyclic-ring-substituted fatty acids, were studied and the 19F-NMR order parameters were correlated with the lipid phase transitions (determined calorimetrically). The lipid phase transition was the prime determinant of overall orientational order regardless of fatty acid structure. Effects upon orientational order attributable to specific structural substituents were discernible, but were secondary to the effects of the lipid phase transition. In the gel state, relative overall order was directly proportional to the temperature of the particular lipid phase transition. Not only the overall order, but also the order profile across the membrane was sensitive to the presence of particular structural substituents. In particular, in the gel state specific fatty acyl structures demonstrated a characteristic disordering effect in the membrane order profile. These various observations can be merged to provide a unified picture of the manner in which fatty acyl chain chemistry modulates the physical state of membrane lipids.

scholarly journals Limonin: A Review of Its Pharmacology, Toxicity, and Pharmacokinetics

Molecules ◽  
2019 ◽  
Vol 24 (20) ◽  
pp. 3679 ◽  
Author(s):  
Fan ◽  
Zhang ◽  
Luo ◽  
Wang ◽  
Tang ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Pharmacological Activity ◽  
Therapeutic Potential ◽  
Wide Spectrum ◽  
Metabolic Enzyme ◽  
Future Research ◽  
Pharmacokinetic Studies ◽  
Pharmacological Effects ◽  
Anti Cancer ◽  
Future Research Directions

Limonin is a natural tetracyclic triterpenoid compound, which widely exists in Euodia rutaecarpa (Juss.) Benth., Phellodendron chinense Schneid., and Coptis chinensis Franch. Its extensive pharmacological effects have attracted considerable attention in recent years. However, there is no systematic review focusing on the pharmacology, toxicity, and pharmacokinetics of limonin. Therefore, this review aimed to provide the latest information on the pharmacology, toxicity, and pharmacokinetics of limonin, exploring the therapeutic potential of this compound and looking for ways to improve efficacy and bioavailability. Limonin has a wide spectrum of pharmacological effects, including anti-cancer, anti-inflammatory and analgesic, anti-bacterial and anti-virus, anti-oxidation, liver protection properties. However, limonin has also been shown to lead to hepatotoxicity, renal toxicity, and genetic damage. Moreover, limonin also has complex impacts on hepatic metabolic enzyme. Pharmacokinetic studies have demonstrated that limonin has poor bioavailability, and the reduction, hydrolysis, and methylation are the main metabolic pathways of limonin. We also found that the position and group of the substituents of limonin are key in affecting pharmacological activity and bioavailability. However, some issues still exist, such as the mechanism of antioxidant activity of limonin not being clear. In addition, there are few studies on the toxicity mechanism of limonin, and the effects of limonin concentration on pharmacological effects and toxicity are not clear, and no researchers have reported any ways in which to reduce the toxicity of limonin. Therefore, future research directions include the mechanism of antioxidant activity of limonin, how the concentration of limonin affects pharmacological effects and toxicity, finding ways to reduce the toxicity of limonin, and structural modification of limonin—one of the key methods necessary to enhance pharmacological activity and bioavailability.

Effect of Inhalation Anesthetics on Spin-Labeled Cholesterol Containing DPPC Vesicles

1988 ◽  
Vol 43 (3-4) ◽  
pp. 264-268 ◽  
Author(s):  
N. Gulfo ◽  
R. Bartucci ◽  
L. Sportelli
Keyword(s):  
Phase Transition ◽  
Diethyl Ether ◽  
Liquid Crystalline ◽  
Main Phase ◽  
Molar Ratio ◽  
Lipid Phase ◽  
Interfacial Region ◽  
Hydrophobic Core ◽  
Hydrophobic Region ◽  
Inhalation Anesthetics

We have investigated by means of electron spin resonance (ESR) spectroscopy the influence of three inhalation anesthetics, i.e. halothane, chloroform and diethyl ether, on the interfacial and hydrophobic region as well of 38 mol% cholesterol containing DPPC unilamellar vesicles. The study has been carried out in the temperature range 25-45 °C. The variation of the order parameter, S, vs temperature of the lipid phase indicates that with this content of cholesterol the characteristic gel → liquid crystalline main phase transition of DPPC, normally occurring at Tt ~ 41 °C, disappears. When halothane and chloroform are added to the vesicles suspension up to [DPPC]/[anesthetic] molar ratio of 1:1 the main phase transition, as detected with the stearic acid spin label I(12,3), reappears again and it results down shifted at Tt ~ 35 and 39 °C, respectively. In presence of diethyl ether, instead, the main phase transition is not observable also at the highest concentration of anesthetic used. Moreover, halothane and chloroform affect similarly the hydrophobic core of cholesterol-!- DPPC vesicles which, in turn, results to be different from the action exerted by diethyl ether in the same region. The ESR findings are discussed in terms of competitive effects shown by cholesterol and inhalation anesthetics. Moreover, the interfacial region of CHOL + DPPC vesicles results to be the target of anesthetics.

SOME ASPECTS OF ZONATION AND FUNCTION OF THE ADRENAL CORTEX

1954 ◽  
Vol 10 (3) ◽  
pp. 266-NP ◽  
Author(s):  
I. CHESTER JONES ◽  
A. WRIGHT
Keyword(s):  
Outer Part ◽  
Outer Region ◽  
Pituitary Hormones ◽  
Zona Glomerulosa ◽  
Female Rats ◽  
Zona Fasciculata ◽  
Zona Reticularis ◽  
Male And Female Rats ◽  
Glomerulosa Cells ◽  
And Function

SUMMARY The adrenal of male and female rats with persistent diabetes insipidus showed a prominent zona fasciculata and zona reticularis. The zona glomerulosa was narrow or absent. The results from this and the preceding three papers are here reviewed together. It is concluded that control of salt-electrolyte metabolism cannot be ascribed to the zona glomerulosa. It is probable that the zona fasciculata is reponsible for most of the adrenocortical secretions. The zona glomerulosa is a vegetative back-water of cells, which is able to produce minimal amounts of adrenocortical secretions without stimulation by pituitary hormones, but is only of significance when the latter are absent. Rising amounts of circulating adrenocorticotrophic hormone (ACTH) can transform the zona glomerulosa into actively secreting cells of the zona fasciculata type. After cessation of such activity the zona glomerulosa re-forms, as the amount of ACTH will maintain only a certain volume of zona fasciculata (and zona reticularis) against the rigid limiting inner circumference formed by the medulla; some of the cells derived from the chief area of cell division in the outer part of the zona fasciculata do not mature to cells of the zona fasciculata type, but form zona glomerulosa cells. It is thought that cell migration occurs from the cells of the outer region of the zona fasciculata to the zona reticularis and that this is, normally, a slow process.

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