Publications by authors named "Atzeri A"

Extracts obtained from Pompia intrea (PI), a traditional candied fruit whose main ingredient is the pompia fruit (Citrus monstruosa L.) were evaluated for the first time. Volatile compounds were evaluated by headspace solid-phase microextraction (HS-SPME) followed by GC-FID/MS analyses.

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The emerging role of the diet in the incidence of intestinal inflammatory diseases has stimulated research on the influence of eating habits with pro-inflammatory properties in inducing epithelial barrier disturbance. Cholesterol oxidation products, namely oxysterols, have been shown to promote and sustain oxidative/inflammatory reactions in human digestive tract. This work investigated in an in vitro model the potential ability of a combination of dietary oxysterols representative of a hyper-cholesterol diet to induce the loss of intestinal epithelial layer integrity.

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The heterodimeric phloroglucinyl pyrone arzanol (Arz) has raised considerable interest because of its antiviral, anti-inflammatory, and antioxidant activity. We have investigated the effect of methylation of the pyrone moiety on the antioxidant activity and cytotoxicity of Arz. This manoeuvre, that left the polyphenolic moiety unscathed, was nevertheless detrimental for antioxidant activity in both the cholesterol thermal degradation- and the Cu-induced liposome oxidation assays, providing evidence of structure-activity relationships that go beyond the preservation of the polyphenolic pharmacophore.

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We studied the total phenols and flavonoids, liposoluble antioxidants, fatty acid and triacylglycerol profiles, and oxidative status of oil obtained from Lycium europaeum fruits following supercritical CO extraction (at 30MPa and 40°C). Linoleic (52%), palmitic (18%), oleic (13%), and α-linolenic (6%) were the main oil fatty acids, while trilinolein and palmitodilinolein/oleodilinolein represented the main triacylglycerols. The oil was characterized by high levels of all-trans-zeaxanthin and all-trans-β-carotene (755 and 332μg/g of oil, respectively), α-tocopherol (308μg/g of oil), total phenols (13.

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The phenolic fraction of a naturally fermented cultivar of table olives, "Tonda di Cagliari," was investigated for the ability to protect Caco-2 cells against oxidative stress and membrane damage induced by tert-butyl hydroperoxyde (TBH). TBH exposure resulted in an alteration of cellular redox status, with an increase in reactive oxygen species (ROS) and a decrease in reduced glutathione (GSH) level. A loss of the epithelial integrity, as indicated by the decrease of the transepithelial electrical resistance value, was also observed over time, together with an intense lipid peroxidation process.

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The phenolic fraction of extra virgin olive oil (EVOO) concentrates before absorption in the intestinal lumen, where it may contribute to the modulation of enterocytes response to oxidative and inflammatory stimuli. We evaluated the ability of two monovarietal EVOOs phenolic extracts, Bosana and Nera di Gonnos/Tonda di Cagliari, typical and widespread varieties in Sardinia (Italy), to counteract in enterocytes like Caco-2 cells the pro-oxidant action of oxidized lipids, tert-butyl hydroperoxide (TBH) or a mixture of oxysterols of dietary origin. We confirmed that TBH treatment causes a significant increase of ROS production, GSH depletion, increase of MDA, fatty acids hydroperoxides and 7-ketocholesterol, and showed first evidence of oxidative imbalance and cell damage due to oxysterols exposure.

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The effect of a diet enriched with mullet bottarga on the lipid profile (total lipids, total cholesterol, unsaturated fatty acids, α-tocopherol, and hydroperoxides) of plasma, liver, kidney, brain, and perirenal adipose tissues of healthy rats was investigated. Rats fed a 10% bottarga enriched-diet for 5 days showed body weights and tissue total lipid and cholesterol levels similar to those of animals fed control diet. Univariate and multivariate results showed that bottarga enriched-diet modified the fatty acid profile in all tissues, except brain.

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The aim of this study was to investigate the ability of the sulfate metabolites of hydroxytyrosol (HT) and tyrosol (TYR) to act as antioxidants counteracting the pro-oxidant effect of oxidized cholesterol in intestinal cells. For this purpose, we synthesized sulfate metabolites of HT and TYR using a chemical methodology and examined their antioxidant activity in Caco-2 monolayers in comparison with the parent compounds. Exposure to oxidized cholesterol led to ROS production, oxidative damage, as indicated by the MDA increase, a decrease of reduced glutathione concentration and an enhancement of glutathione peroxidase activity.

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The present study aimed to examine the potential anticancer properties of fixed oil obtained from Maltese mushroom (Cynomorium coccineum L.), an edible, non-photosynthetic plant, used in traditional medicine of Mediterranean countries to treat various ailments and as an emergency food during the famine. We investigated the effect of the oil, obtained from dried stems by supercritical fractioned extraction with CO2, on B16F10 melanoma and colon cancer Caco-2 cell viability and lipid profile.

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The salted-semidried mullet ovary product, bottarga, is a Mediterranean food rich in n-3 PUFA EPA and DHA. We studied and compared the effects on cell viability, sensitivity to the anti-tumor drug 5-fluorouracil, and lipid composition, in colon cancer Caco-2 cells after 24 h incubation with oils and hydrophilic extracts obtained from two bottarga samples stored at different conditions. The cellular absorption of bottarga lipids was assessed in cancer cells by the evaluation of lipid accumulation in cytoplasmic lipid droplets by fluorescence microscopy.

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One of the most important sites of polyphenol action seems to be in the gastrointestinal system before absorption. We investigated the ability of three wine phenolic extracts, obtained from grape varieties grown in Sardinia, Cannonau (red), Vermentino and Malvasia (white), to exert an antioxidant action against tert-butyl hydroperoxide (TBH)-induced oxidative damage to Caco-2 cell monolayers as a model system of the human intestine. TBH treatment caused the disruption of epithelial integrity, measured as transepithelial electrical resistance, and markers of the peroxidation process of membrane lipids, MDA, fatty acid hydroperoxides and 7-ketocholesterol.

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Cynomorium coccineum L. is a non-photosynthetic plant, spread over Mediterranean countries, amply used in traditional medicine. We investigated the composition and effect on intestinal Caco-2 cell viability and lipid profile of fixed oil obtained from dried stems of the plant.

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Unlabelled: Isolation of volatile and fixed oils from nutmeg have been obtained by supercritical fractioned extraction with carbon dioxide. Extraction experiments were carried out at pressures of 90 and 250 bar and temperature of 40 °C. The extraction step performed at 90 bar produced a volatile fraction mainly formed by myristicin (32.

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Unlabelled: The salted and semidried mullet (Mugil cephalus) ovary product (bottarga) is proposed as an important source of the long-chain n-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic acid, and docosahexaenoic acid. In this work, we investigated the extent of lipid oxidation and browning of grated bottarga samples during 7 mo of storage at -20 °C, 2 to 3 °C in the absence of light, and at room temperature in the presence or absence of light. Modifications of the levels of total choline (as index of phospholipid breakdown), total sugars, and free amino acids such as lysine, methionine, and tryptophan (involved in nonenzymatic browning) were also studied at different storage conditions.

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The antioxidant activity of several honeys was evaluated considering the different contribution of entire samples. The strawberry tree honey emerged as the richest in total phenols and the most active honey in the DPPH and FRAP tests, and could protect cholesterol against oxidative degradation (140°C). Homogentisic acid (2,5-dihydroxyphenylacetic acid, HGA), the main phenolic compound from strawberry tree honey, showed interesting antioxidant and antiradical activities, and protective effect against thermal-cholesterol degradation, comparable to those of well known antioxidants.

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Hydroxytyrosol (2-(3',4'-dihydroxyphenyl)ethanol; HT), the most active ortho-diphenolic compound, present either in free or esterified form in extravirgin olive oil, is extensively metabolized in vivo mainly to O-methylated, O-sulfated and glucuronide metabolites. We investigated the capacity of three glucuronide metabolites of HT, 3'-O-β-d-glucuronide and 4'-O-β-d-glucuronide derivatives and 2-(3',4'-dihydroxyphenyl)ethanol-1-O-β-d-glucuronide, in comparison with the parent compound, to inhibit H(2)O(2) induced oxidative damage and cell death in LLC-PK1 cells, a porcine kidney epithelial cell line. H(2)O(2) treatment exerted a toxic effect inducing cell death, interacting selectively within the pro-death extracellular-signal relate kinase (ERK 1/2) and the pro-survival Akt/PKB signaling pathways.

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The importance of n-3 polyunsaturated fatty acid (n-3 PUFA) intake has long been recognized in human nutrition. Although health benefits, n-3 PUFA are subject to rapid and/or extensive oxidation during processing and storage, resulting in potential alteration in nutritional composition and quality of food. Bottarga, a salted and semi-dried mullet ( Mugil cephalus ) ovary product, is proposed as an important source of n-3 PUFA, having high levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

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This study examines the protective effect of arzanol, a pyrone-phloroglucinol etherodimer from Helichrysum italicum subsp. microphyllum, against the oxidative modification of lipid components induced by Cu(2+) ions in human low density lipoprotein (LDL) and by tert-butyl hydroperoxide (TBH) in cell membranes. LDL pre-treatment with arzanol significantly preserved lipoproteins from oxidative damage at 2h of oxidation, and showed a remarkable protective effect on the reduction of polyunsaturated fatty acids and cholesterol levels, inhibiting the increase of oxidative products (conjugated dienes fatty acids hydroperoxides, 7β-hydroxycholesterol, and 7-ketocholesterol).

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Complex polyphenols present in extravirgin olive oil are not directly absorbed, but undergo gastrointestinal biotransformation, increasing the relative amount of tyrosol (TYR) and hydroxytyrosol (HT) entering the small and large intestine. We investigated the capacity of TYR and HT to inhibit the insult of dietary lipid hydroperoxydes on the intestinal mucosa, using cultures of Caco-2, a cell line with enterocyte-like features, and studying the effect of tert-butyl hydroperoxide (TBH) treatment on specific cell membrane lipid targets. The effect of homovanillic alcohol (HVA), metabolite of HT in humans and detected as metabolite of HT in Caco-2 cells, was also evaluated.

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Bioavailability studies in animals and humans fed with extravirgin olive oil demonstrated that hydroxytyrosol and tyrosol, the major simple phenolic compounds in extravirgin olive oil, are dose-dependently absorbed and excreted. Once absorbed, they undergo extensive metabolism; hydroxytyrosol and tyrosol concentrate mainly in the kidney, where they may exert an important role in the prevention of oxidative stress induced renal dysfunction. In this study we monitored the ability of hydroxytyrosol and tyrosol to protect renal cells (LLC-PK1) following oxidative damage induced by H2O2.

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The introduction of an iodine atom on the vanillyl moiety of nonivamide causes a switch in the vanilloid activity (TRPV1 antagonism versus TRPV1 desensitization) and nullifies the aversive properties of capsaicinoids. In the present study we investigated the effect of iodination in the vanillyl moiety on the antioxidant activity of capsaicinoids. To this aim, we have compared the protective effects of nonivamide and three iododerivatives, 2-iodononivamide (2IN), 5-iodononivamide (5IN), and 6-iodononivamide (6IN) in a series of in vitro models of lipid oxidation, namely the autoxidation and the FeCl(3)-mediated oxidation of linoleic acid at 37 degrees C and the thermal (140 degrees C), solvent-free oxidation of cholesterol.

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We investigated the capacity of hydroxytyrosol (HT), 3,4-dihydroxyphenylethanol, and homovanillic alcohol (HVA), 4-hydroxy-3-methoxy-phenylethanol, to inhibit H(2)O(2) induced oxidative damage in LLC-PK1, a porcine kidney epithelial cell line, studying the effect of H(2)O(2) on specific cell membrane lipid targets, unsaturated fatty acids and cholesterol. Exposure to H(2)O(2) induced a significant increase of the level of MDA together with a disruption of the membrane structure, with the loss of unsaturated fatty acids, cholesterol and alpha-tocopherol, and the formation of fatty acids hydroperoxides and 7-ketocholesterol. Pretreatment with HT protected renal cells from oxidative damage: the level of membrane lipids was preserved and there was no significant detection of oxidation products.

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Myrtle (Myrtus communis L.), a culinary spice and flavouring agent for alcoholic beverages widespread in the Mediterranean area and especially in Sardinia, contains the structurally unique oligomeric non-prenylated acylphloroglucinols, semimyrtucommulone and myrtucommulone A, whose antioxidant activity was investigated during the oxidative modification of lipid molecules implicated in the onset of cardiovascular diseases. Both acylphloroglucinols showed powerful antioxidant properties during the thermal (140 degrees C), solvent-free degradation of cholesterol.

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This study investigated the effect of synthetic capsiate, a simplified analogue of capsiate, and vanillyl alcohol on the oxidative stress induced by tert-butyl hydroperoxide (TBH) in a line of fibroblasts derived from monkey kidney (Vero cells). In response to the TBH-mediated oxidative stress, a reduction of the levels of total unsaturated fatty acids and cholesterol was observed, and a rise in the concentrations of conjugated dienes fatty acids hydroperoxides and 7-ketocholesterol. Pretreatment with both synthetic capsiate and vanillyl alcohol preserved Vero cells from oxidative damage and showed a remarkable protective effect on the reduction of the levels of total unsaturated fatty acids and cholesterol, inhibiting the increase of MDA, conjugated dienes fatty acids hydroperoxides, and 7-ketocholesterol.

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The phenolic fraction of virgin olive oil exerts preventive effects against reactive oxygen species mediated degenerative diseases. To investigate its action as inhibitor of lipid peroxidation in vivo, we treated Wistar rats with olive oil minor polar components (MPC) (25-50 mg/kg bw) prior to the administration of a sublethal dose (15 mg Fe/kg bw) of ferric-nitrilotriacetate (Fe-NTA). Intraperitoneal injection (i.

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