Lipid Separation from Urtica dioica: Existence of Platelet-Activating Factor

The common wild plant nettle, especially Urtica dioica, is one of the most potent plants in producing direct irritation to the skin (urticaria). In this study, total lipids of Urtica dioica were separated into neutral and polar lipids, which were further fractionated by high-performance liquid chromatography (HPLC). Triglycerides, sterol-esters, fatty acids, fatty acid methyl esters, glyceryl ethers, sterols, tocopherols, diglycerides, and galactosyldiglycerides were identified as the main neutral lipid classes by comparing their retention times on an HPLC column and their migration following spraying with specific reagents on thin-layer chromatography (TLC) with standards. Four main classes of phospholipids (i.e., phosphatidylinositol, phosphatidylethanolamine, phosphatidylcholine, and lysophosphatidylcholine) were also identified. A phospholipid that induced platelet aggregation was identified as platelet-activating factor on the basis of biological, chemical, and spectral methods

A simple and precise method for the routine determination of platelet-activating factor in blood and urine

A simple and precise method is described for the measurement of platelet-activating factor (PAF) in blood and urine. The method involves the isolation of PAF from blood samples by two successive steps. In the first step, blood proteins are precipitated with ethanol and the "free" PAF, i.e. the PAF which is extractable with ethanol, is recovered. In the second step, "bound" PAF, i.e., PAF not extractable with ethanol, is extracted from the protein precipitate with chloroform/methanol/water. The extraction of PAF from urine samples requires only the ethanol extraction step. "Free" and "bound" PAF are then each fractionated by silicic acid column chromatography, and the methanol/water eluent containing PAF is then further fractionated by high-performance liquid chromatography using an isocratic solvent system of acetonitrile/methanol/water. PAF is then quantitated by measuring its ability to induce platelet aggregation in an aggregometer. Application of the method to blood and urine samples from twenty-three healthy volunteers revealed PAF levels in blood of 140-480 pg/mL (630-254.4 pg "free" PAF/mL and 64-225.6 pg "bound" PAF/mL), and of 1.2-4.0 pg PAF/mL in urine. The method overcomes various technical problems and was shown to be very precise. It should prove useful for monitoring PAF levels in various disease conditions. © 1994 American Oil Chemists' Society

Lipid Separation from Urtica dioica: Existence of Platelet-Activating Factor

The common wild plant nettle, especially Urtica dioica, is one of the most potent plants in producing direct irritation to the skin (urticaria). In this study, total lipids of Urtica dioica were separated into neutral and polar lipids, which were further fractionated by high-performance liquid chromatography (HPLC). Triglycerides, sterol-esters, fatty acids, fatty acid methyl esters, glyceryl ethers, sterols, tocopherols, diglycerides, and galactosyldiglycerides were identified as the main neutral lipid classes by comparing their retention times on an HPLC column and their migration following spraying with specific reagents on thin-layer chromatography (TLC) with standards. Four main classes of phospholipids (i.e., phosphatidylinositol, phosphatidylethanolamine, phosphatidylcholine, and lysophosphatidylcholine) were also identified. A phospholipid that induced platelet aggregation was identified as platelet-activating factor on the basis of biological, chemical, and spectral methods

In-vitro gastric cancer prevention by a polyphenol-rich extract from olives through induction of apoptosis

In recent years, natural dietary agents have drawn a great deal of attention owing to their demonstrated ability to suppress cancer. We aimed to investigate the in-vitro gastric cancer preventive activity of a methanol extract obtained from table olives of Greek origin. Tested were AGS cell proliferation, induction of apoptosis and inhibition of inflammation. AGS stomach cancer cells were cultured at a density of 105 cells/ml. Methanol extract of olive was added to cultures at concentrations of 2.0,1.6,1.0, and 0.4 μg phenols/ml. Effect on cellular viability was evaluated via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and percentages of early and late apoptotic cells were assayed by annexin V-FITC staining on a FACS scan. Interleukin-8 (IL-8) and intercellular adhesion molecule (ICAM)-1 mRNA and protein production were measured by applying reverse transcriptase-PCR and enzyme-linked immunosorbent assay. Olive extract significantly suppressed cell proliferation at 2.0,1.6, and 1.0 μg phenols/ml. Flow cytometric analysis of Annexin-V labeled cells indicated that 2.0 μg phenols/ml significantly induced apoptosis. Similarly, at 2.0,1.6, and 1.0 μg phenols/ ml a significant decrease of ICAM-1 and IL-8 protein levels was observed. ICAM-1, as well as IL-8, mRNA expression were decreased in the presence of 2.0μg phenols/ml. Results indicate that the methanol extract from olives, rich in phenolic compounds, exhibits gastric cancer preventive efficacy by limiting cell proliferation, inducing cell death and suppressing inflammation in AGS cells. European Journal of Cancer Prevention 18:33-39 © 2009 Wolters Kluwer Health

Separation of several main glycolipids into classes and partially into species by HPLC and UV-detection

The separation and the estimation of several main glycolipid classes as well as of some of these classes into main subclasses (or species) by reverse phase and normal phase high performance liquid chromatography and UV detection, is described. Two different gradient elutions onto a C18 column and onto a silica column, respectively, and an isocratic elution onto a strong cation exchange column were performed, with detection at 206 nm. Separations were achieved within 30 min. in the reverse phase and normal phase modes and within 10 min. in the cation exchange mode. The following glycolipids standard classes were tested: gangliosides, sulfate cerebrosides (sulfatides), digalactosyl-diglycerides, galactosyl-cerebroside as well as ceramides (the backbone of sphingoglycolipids), N-palmitoyl-sphingosine (a synthetic ceramide) and a phospholipid, cardiolipin. Some species of digalactosyl-diglycerides and galactosyl-cerebrosides were also separated. Application of the present method on the separation of glycolipids from animal tissues is represented

Isolation and complete separation of lipids from natural sources

A method of isolation and complete separation of lipids from natural sources into classes and species is reported which combines our previously published techniques with new techniques described in this article for the first time. Pigments are separated from crude total lipid extracts with two successive TLC systems: a) petroleum ether/benzene/glacial acetic acid (30:70:2) and b) acetone/methanol/water (40:20:1). Pigment-free total lipids are separated on a silicic acid column into neutral, glyco- and phospholipids. Neutral, glyco- and phospholipids are separated into classes and species by suitable HPLC methods

Lipids of Pinus halepensis pollen

The total lipids of Pinus halepensis pollen were separated into individual classes of neutral and polar lipids and the components of each class were identified and determined quantitatively. Free fatty acids, waxes and triacylglycerols were found as the main constituents of neutral lipids and phosphatidylcholine and phosphatidylethanolamine of polar lipids. Glycerylether derivatives were detected in neutral and polar lipid fractions. Free and esterified volatile fatty acids were also found in pollen and its neutral lipid fraction. © 1985

Pistacia lentiscus resin regulates intestinal damage and inflammation in trinitrobenzene sulfonic acid-induced colitis

Mastic (Pistacia lentiscus) of the Anacardiaceae family has exhibited anti-inflammatory and antioxidant properties in patients with Crohn's disease. This study was based on the hypothesis that mastic inhibits intestinal damage in inflammatory bowel disease, regulating inflammation and oxidative stress in intestinal epithelium. Four different dosages of P. lentiscus powder in the form of powder were administered orally to trinitrobenzene sulfonic acid-induced colitic rats. Eighty-four male Wistar rats were randomly assigned to seven groups: A, control; B, colitic; C-F, colitic rats daily supplemented with P. lentiscus powder at (C) 50mg/kg, (D) 100mg/kg, (E) 200mg/kg, and (F) 300mg/kg of body weight; and G, colitic rats treated daily with cortisone (25μg/kg of body weight). Colonic damage was assessed microscopically. The cytokines tumor necrosis factor-α, intercellular adhesion molecule-1 (ICAM-1), interleukin (IL)-6, IL-8, and IL-10 and malonaldehyde were measured in colonic specimens. Results were expressed as mean±SE values. Histological amelioration of colitis (P≤.001) and significant differences in colonic indices occurred after 3 days of treatment. Daily administration of 100mg of P. lentiscus powder/kg of body weight decreased all inflammatory cytokines (P≤.05), whereas 50mg of P. lentiscus powder/kg of body weight and cortisone treatment reduced only ICAM-1 (P≤.05 and P≤.01, respectively). Malonaldehyde was significantly suppressed in all treated groups (P≤.01). IL-10 remained unchanged. Cytokines and malonaldehyde remained unaltered after 6 days of treatment. Thus P. lentiscus powder could possibly have a therapeutic role in Crohn's disease, regulating oxidant/antioxidant balance and modulating inflammation. © Copyright 2011, Mary Ann Liebert, Inc. and Korean Society of Food Science and Nutrition 2011

Serum lipid profile and inflammatory markers in the aorta of cholesterol-fed rats supplemented with extra virgin olive oil, sunflower oils and oil-products

Extra virgin olive oil (EVOO) major and minor component anti-inflammatory effect on aorta was evaluated; Wistar rats were fed (9 weeks) on either a high-cholesterol diet (HCD) or a HCD supplemented with oils, i.e. EVOO, sunflower oil (SO), high-oleic sunflower oil (HOSO), or oilproducts modified to their phenolic content, i.e. phenolics deprived-EVOO [EVOO(-)], SO enriched with the EVOO phenolics [SO(+)], HOSO enriched with the EVOO phenolics [HOSO(+)]. HCD induced dyslipidemia and resulted in higher aorta adhesion molecules levels at euthanasia. Groups receiving EVOO, EVOO(-), HOSO, HOSO(+) presented higher serum TC and LDL-c levels compared to cholesterol-fed rats; attenuation of aorta E-selectin levels was also observed. In EVOO/EVOO(-) groups, aorta vascular endothelial adhesion molecule-1 (VCAM-1) was lower compared to HCD animals. SO/SO(+) diets had no effect on endothelial dysfunction amelioration. Overall, our results suggest that major and/or minor EVOO constituents improve aorta E-selectin and VCAM-1, while serum lipids do not benefit. Copyright © 2015 Taylor & Francis

Chios Mastic Fractions in Experimental Colitis: Implication of the Nuclear Factor κb Pathway in Cultured HT29 Cells

The Pistacia lentiscus tree gives a resinous exudate called Chios mastic (CM) rich in triterpenoids. CM can be fractionated into acidic and neutral fractions (AF and NF, respectively). Oleanolic acid (OA) is a major triterpenic acid in CM with several antioxidant and anti-inflammatory properties. We have recently shown that CM is beneficial in experimental colitis in the form of powder mixture with inulin, as supplied commercially. However, the bioactive fraction or compound of CM is unidentified. Thus, based on the hypothesis that terpenoids exhibit functional activities via distinguishable pathways, we fractionated CM and applied different fractions or individual OA in experimental colitis. Furthermore, we investigated the mechanism underlying this effect in human colon epithelial cells. CM powder mixture (100mg/kg of body weight) or the respective CM powder mixture components (i.e., inulin, AF, NF, or OA) were individually administered in trinitrobenzene sulfonic acid-treated rats. Colonic damage was assessed microscopically, and levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-8, and intercellular adhesion molecule-1were measured. A model of inflammation in co-cultured human colon epithelial HT29 cells and monocytes/macrophages was established. Lactate dehydrogenase release and levels of TNF-α, IL-8, and nuclear factor-κB (NF-κB) p65 were measured. In vivo, histological amelioration of colitis and significant regulation in inflammation occurred with CM powder mixture, even at the mRNA level. Although no histological improvement was observed, AF and NF reduced levels of inflammatory markers. Inulin was ineffective. In vitro, CM treatment down-regulated IL-8 and NF-κB p65. Neither fractions nor OA was the bioactive component solely. Most probably, the entire CM rather than its individual fractions reduces inflammation via NF-κB regulation. © Copyright 2012, Mary Ann Liebert, Inc