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Are olive oil diets antithrombotic? Diets enriched with olive, rapeseed, or sunflower oil affect postprandial factor VII differently.

BACKGROUND: The incidence of ischemic heart disease (IHD) in Crete was lower than expected on the basis of blood lipid concentrations of participants in the Seven Countries Study. A favorable effect of a high intake of olive oil on thrombogenesis may have contributed to this finding. OBJECTIVE: We compared the effects of virgin olive oil with those of rapeseed and sunflower oils on blood coagulation factor VII (FVII), a key factor in thrombogenesis. DESIGN: In a randomized and strictly controlled crossover study, 18 healthy young men consumed diets enriched with 5 g/MJ (19% of total energy) olive oil, sunflower oil, or rapeseed oil for periods of 3 wk. On the final day of each period, participants consumed standardized high-fat meals (42% of energy as fat). Fasting and nonfasting blood samples were collected after each period. RESULTS: Mean (+/-SEM) nonfasting peak concentrations of activated FVII (FVIIa) were 11.3 +/- 5.1 U/L lower after olive oil than after sunflower oil, an 18% reduction (P < 0.05). Olive oil also tended to cause lower FVIIa peak concentrations than did rapeseed oil (mean difference: 8.6 U/L, a 15% reduction; P = 0.09). There were no significant differences between diets with respect to nonfasting factor VII coagulant activity (FVII:c), prothrombin fragment 1+2 (F1+2), and tissue factor pathway inhibitor (TFPI) concentrations, or with respect to fasting plasma values of FVII protein, FVII:c, FVIIa, F1+2, or TFPI. CONCLUSION: A background diet rich in olive oil may attenuate the acute procoagulant effects of fatty meals, which might contribute to the low incidence of IHD in Mediterranean areas.

Adult↗

Synchronous fluorescence spectroscopy for quantitative determination of virgin olive oil adulteration with sunflower oil.

Adulteration of extra virgin olive oil with sunflower oil is a major issue for the olive oil industry. In this paper, the potential of total synchronous fluorescence (TSyF) spectra to differentiate virgin olive oil from sunflower oil and synchronous fluorescence (SyF) spectra combined with multivariate analysis to assess the adulteration of virgin olive oil are demonstrated. TSyF spectra were acquired by varying the excitation wavelength in the region 270-720 nm and the wavelength interval (Deltalambda) in the region from 20 to 120 nm. TSyF contour plots for sunflower, in contrast to virgin olive oil, show a fluorescence region in the excitation wavelength range 325-385 nm. Fifteen different virgin olive oil samples were adulterated with sunflower oil at varying levels (0.5-95%) resulting in one hundred and thirty six mixtures. The partial least-squares regression model was used for quantification of the adulteration using wavelength intervals of 20 and 80 nm. This technique is useful for detection of sunflower oil in virgin olive oil at levels down to 3.4% (w/v) in just two and a half minutes using an 80-nm wavelength interval.

Olive Oil↗

Postprandial LDL phenolic content and LDL oxidation are modulated by olive oil phenolic compounds in humans.

Olive oil phenolic compounds are potent antioxidants in vitro, but evidence for antioxidant action in vivo is controversial. We examined the role of the phenolic compounds from olive oil on postprandial oxidative stress and LDL antioxidant content. Oral fat loads of 40 mL of similar olive oils, but with high (366 mg/kg), moderate (164 mg/kg), and low (2.7 mg/kg) phenolic content, were administered to 12 healthy male volunteers in a cross-over study design after a washout period in which a strict antioxidant diet was followed. Tyrosol and hydroxytyrosol, phenolic compounds of olive oil, were dose-dependently absorbed (p<0.001). Total phenolic compounds in LDL increased at postprandial state in a direct relationship with the phenolic compounds content of the olive oil ingested (p<0.05). Plasma concentrations of tyrosol, hydroxytyrosol, and 3-O-methyl-hydroxytyrosol directly correlated with changes in the total phenolic compounds content of the LDL after the high phenolic compounds content olive oil ingestion. A 40 mL dose of olive oil promoted a postprandial oxidative stress, the degree of LDL oxidation being lower as the phenolic content of the olive oil administered increases. In conclusion, olive oil phenolic content seems to modulate the LDL phenolic content and the postprandial oxidative stress promoted by 40 mL olive oil ingestion in humans.

Adult↗

Different clearance of intravenously administered olive oil and soybean-oil emulsions: role of hepatic lipase.

The elimination of two intravenously administered fat emulsions consisting of either 20% (wt:vol) soybean oil or 17% olive oil plus 3% soybean oil was studied in six normolipidemic young men according to a randomized crossover protocol. Slower elimination was found with the olive oil emulsion. A significantly lower maximal removal capacity (K1) and fractional catabolic rate (K2) were measured with olive oil emulsion (P < 0.05). Removal of olive oil emulsion was inversely related to hepatic lipase activity (r = -0.85; P < 0.05). Removal of soybean-oil emulsion was related to the initial plasma triglyceride concentration (r = -0.84; P < 0.05) but not to lipolytic activity. In vivo apolipoprotein C-II binding was similar for both emulsions. Therefore, hepatic lipase activity is more important in the elimination of olive oil emulsions than soybean-oil emulsions. The faster elimination of soybean-oil emulsions suggests an additional elimination pathway, such as the reticuloendothelial system.

Adult↗

Phytoavailability and extractability of potassium, magnesium and manganese in calcareous soil amended with olive oil wastewater.

Land disposal of olive oil wastewater using it as a soil amendment requires a knowledge of the effects that its application may produce on the status of the mineral nutrients in the plant-soil system. A pot experiment using calcareous soil was performed in a growth chamber to examine the effects of olive oil wastewater on the availability and postharvest soil extractability of K, Mg and Mn. The experiment included 6 treatments: two rates of olive oil wastewater, two mineral fertilizer treatments containing K (which supplied K in amounts equivalent to the K supplied by the olive oil wastewater treatments), a K-free mineral fertilizer treatment, and a control. The pots were sown with ryegrass as the test plant, harvesting 3 times at intervals of one month. Olive oil wastewater has demonstrated a considerable capacity for supplying K that can be assimilated by the plant, tending in fact to surpass the mineral potassium fertilizer tested. The application of olive oil wastewater tends to reduce the concentration of Mg in the plant, similarly to the effect of adding mineral potassium fertilizer. An enhancement of Mn availability takes place in the soil amended with olive oil wastewater, which on occasion has produced Mn concentrations in plant that could be considered phytotoxic or at least excessive. After harvesting, we observed an increase in the amount of exchangeable K in soil with added industrial wastewater. However, these increases are lower than those in soil treated with mineral potassium fertilizer. The levels of exchangeable, carbonate-bound, organic-bound and residual Mg in soil were higher in treatments incorporating olive oil wastewater than in those with added mineral K, with the opposite tendency occurring in the amount of Fe-Mn oxides-bound Mg in soil. Treatments based on olive oil wastewater, especially in high doses, increased the amount of exchangeable and carbonate-bound Mn in soil, in comparison with treatments adding mineral fertilizers with or without K. In contrast, the addition of industrial wastewater caused a drop in the amount of Fe-Mn oxides-bound and organic-bound Mn in soil.

Industrial Waste↗

Analytical determination of polyphenols in olive oils.

The increasing popularity of olive oil is mainly attributed to its high content of oleic acid, which may affect the plasma lipid/lipoprotein profiles, and its richness in phenolic compounds, which act as natural antioxidants and may contribute to the prevention of human disease. An overview of analytical methods for the measurement of polyphenols in olive oil is presented. In principle, the analytical procedure for the determination of individual phenolic compounds in virgin olive oil involves three basic steps: extraction from the oil sample, analytical separation, and quantification. A great number of procedures for the isolation of the polar phenolic fraction of virgin olive oil, utilizing two basic extraction techniques, LLE or SPE, have been included. The reviewed techniques are those based on spectrophotometric methods, as well as analytical separation (gas chromatography (GC), high-performance liquid chromatography (HPLC), and capillary electrophoresis (CE)). Many reports in the literature determine the total amount of phenolic compounds in olive oils by spectrophometric analysis and characterize their phenolic patterns by capillary gas chromatography (CGC) and, mainly, by reverse phase high-performance liquid chromatography (RP-HPLC); however, CE has recently been applied to the analysis of phenolic compound of olive oil and has opened up great expectations, especially because of the higher resolution, reduced sample volume, and analysis duration. CE might represent a good compromise between analysis time and satisfactory characterization for some classes of phenolic compounds of virgin olive oils.

Antioxidants↗

Effects of a high olive oil diet on the clinical behavior and histopathological features of rat DMBA-induced mammary tumors compared with a high corn oil diet.

Effects of a high virgin olive oil diet on the promotion stage of dimethylbenz(alpha)anthracene-induced mammary carcinogenesis in rats were investigated in comparison with those of a high corn oil diet. Animals were randomly placed into 4 groups: control, fed a normolipidic control diet (3% corn oil); M, fed a high corn oil diet (20%); O, fed a high olive oil diet (3% corn oil plus 17% olive oil); and MO, fed the high olive oil diet after 33 days of high corn oil diet. Whereas the high corn oil diet clearly stimulated the mammary carcinogenesis, reducing the latency time and increasing the tumor incidence, multiplicity and volume, the high olive oil diet led to a lower tumor incidence than in the former group, a latency time similar to that of the control and lower tumor multiplicity and volume even than in the control group. Moreover, the histopathological features of the adenocarcinomas in olive oil groups were compatible with a greater degree of differentiation. These data suggest that the high virgin olive oil diet would have acted as a negative modulator of the experimental mammary carcinogenesis conferring to the tumors a more benign clinical behavior and a lower histopathological malignancy in comparison with the control and high corn oil diets.

9,10-Dimethyl-1,2-benzanthracene↗

Detecting and quantifying sunflower oil adulteration in extra virgin olive oils from the eastern mediterranean by visible and near-infrared spectroscopy.

One hundred and thirty-eight oil samples have been analyzed by visible and near-infrared transflectance spectroscopy. These comprised 46 pure extra virgin olive oils and the same oils adulterated with 1% (w/w) and 5% (w/w) sunflower oil. A number of multivariate mathematical approaches were investigated to detect and quantify the sunflower oil adulterant. These included hierarchical cluster analysis, soft independent modeling of class analogy (SIMCA method), and partial least squares regression (PLS). A number of wavelength ranges and data pretreatments were explored. The accuracy of these mathematical models was compared, and the most successful models were identified. Complete classification accuracy was achieved using 1st derivative spectral data in the 400-2498 nm range. Prediction of adulterant content was possible with a standard error equal to 0.8% using 1st derivative data between 1100 and 2498 nm. Spectral features and chemical literature were studied to isolate the structural basis for these models.

Food Contamination↗

Lipid peroxidation and glutathione system in hyperlipemic rabbits: influence of olive oil administration.

We studied the effect of supplementation (10% w/w) of a hyperlipemic diet (1% cholesterol) with olive oil (OLIV) for 6 weeks in four groups of 10 rabbits each. At the end of this period, we determined lipid peroxidation, glutathione content, and glutathione peroxidase, reductase and transferase activities in liver, brain, heart, aorta and platelets. The atherogenic diet increased tissue lipid peroxidation and decreased the protective antioxidant effect of glutathione. Dietary supplementation with olive oil reduced tissue lipid peroxidation by 71.6% in liver, 20.3% in brain, 84.5% in heart, 63.6% in aorta, 72% in platelets. The ratios total/oxidized glutathione were increased in all tissues (49% in liver, 48% in brain, 45% in heart, 83% in aorta, 70% in platelets). Olive oil increased glutathione peroxidase and transferase activities in all tissues. We conclude that in rabbits made hyperlipemic with a diet rich in saturated fatty acids, olive oil decreased tissue oxidative stress.

Animals↗

Qualitative and semiquantitative analysis of phenolic compounds in extra virgin olive oils as a function of the ripening degree of olive fruits by different analytical techniques.

Capillary electrophoresis (CE) can be effectively used as a fast screening tool to obtain qualitative and semiquantitative information about simple and complex phenolic compounds of extra virgin olive oil. Three simple phenols (tyrosol, hydroxytyrosol, and vanillic acid), a secoiridoid derivative (deacetoxy oleuropein aglycon), and two lignans (pinoresinol and acetoxypinoresinol) were detected as the main compounds in extra virgin olive oils by high-performance liquid chromatography (HPLC) and capillary zone electrophoresis (CZE). Spectrophotometric indices, radical scavenging activity, and oxidative stability of extra virgin olive oil samples obtained from olives hand-picked at different ripening degrees were statistically correlated with the CZE and HPLC quantification. The concentration of phenols in extra virgin olive oil decreased with ripeness of olive fruits. The high correlations found between CZE and the other analytical results indicate that CE can be applied as a rapid and reliable tool to routinely determine phenolic compounds in extra virgin olive oils.

Chromatography, High Pressure Liquid↗

Accelerative effect of olive oil on adrenal corticosterone secretion in rats loaded with single or repetitive immersion-restraint stress.

The present study was performed to clarify the effects of dietary oils on physiological and metabolic changes induced by a stress, using one-time or repetitive water-immersion of restrained rats (single or repetitive stress) as an experimental stress load. In rats fed any test diets containing 20%) of the mixture of tripalmitin, tristearin, and corn oil (PSC), olive oil (OLI). safflower oil (SAF), and linseed oil (LIS) with repetitive stress loading, body weight gains and food intakes were generally reduced. The weights of the thymus and spleen also declined, but the adrenal weights were enhanced. Particularly, the increase in the adrenal weight of rats given the OLI diet was greater than of rats supplied with other diets. When the rats were loaded with the single or repetitive stress, the concentrations of urea, lipid peroxide, and corticosterone in the plasma were increased in rats fed any of dietary oils. The rise of plasma corticosterone level was especially great in rats fed the OLI diet. The concentrations of total cholesterol (T-CHOL) and triglyceride (TG) in the plasma and liver generally tended to be higher in rats fed the OLI diet than in rats given the other diets with and without stress exposure. Plasma corticosterone concentration was correlated to the adrenal weight (r=0.87, p<0.05). This study showed that OLI especially enhanced the adrenal weight in rats exposed to the repetitive stress and further raised the increased secretion of adrenal corticosterone in rats loaded with the single or repetitive stress compared with the other oils. The mechanism explaining these actions of OLI was inferred to be related to the levels of T-CHOL and TG in the plasma and liver generally enhanced by stress.

Adrenal Cortex↗

Different effects of diets rich in olive oil, rapeseed oil and sunflower-seed oil on postprandial lipid and lipoprotein concentrations and on lipoprotein oxidation susceptibility.

Elevated concentrations of fasting and non-fasting triacylglycerol-rich lipoproteins (TRL) as well as oxidative changes of lipoproteins may increase the risk of ischaemic heart disease. To compare the effects of different diets rich in unsaturated fatty acids on the concentrations and in vitro oxidation of fasting and postprandial lipoproteins eighteen males consumed diets enriched with rapeseed oil (RO), olive oil (OO), or sunflower-seed oil (SO) in randomised order for periods of 3 weeks followed by a RO test meal. In the postprandial state the concentrations of cholesterol and triacylglycerol (TAG) in TRL were higher after consumption of OO compared with RO and SO (P<0.04), possibly related to differences in the fasting state. The propagation rates for VLDL and LDL oxidation were higher in the postprandial compared with the fasting state irrespective of diet. In the fasting state, the propagation rates were highest after SO (P<0.001), and in the postprandial state, SO gave rise to a shorter VLDL lag time (P=0.03) and a higher propagation rate than OO consumption (P=0.04). Overall, the SO diet resulted in a higher postprandial propagation rate of LDL (P<0.001) compared with RO and OO, while there was no effect of diet on LDL oxidation lag time. Our results suggest that RO and SO diets lower the postprandial cholesterol and TAG concentrations compared with OO, while RO and OO diets result in similar and lower in vitro susceptibility to oxidation of lipoproteins than SO.

Adult↗

Antithrombotic potential of olive oil administration in rabbits with elevated cholesterol.

Olive oil is the main source of dietary fatty acids in the Mediterranean region. The objective of this study was to evaluate the effect of dietary supplementation with virgin olive oil in an experimental model with rabbits fed an atherogenic diet (saturated fat 48% of total fat). Four different groups of 10 animals each were studied: (1) normolipemic diet (NLD), (2) atherogenic diet or saturated fatty acid-enriched diet (SFAED), (3) NLD with 15% olive oil (NLD+OLIV), and (4) SFAED with 15% virgin olive oil (SFAED+OLIV). The animals were fed the experimental diets for 6 weeks, after which we determined serum lipid profile (total cholesterol, HDL-cholesterol, and triglycerides), platelet aggregation, platelet thromboxane B(2), aortic prostacyclin, and platelet and vascular lipid peroxidation. Scanning electron microscopic images of the vascular endothelium were studied, as were morphometric parameters in the arterial wall and thrombogenicity of the subendothelium (annular perfusion chamber). Animals fed the SFAED showed platelet hyperactivity and increased subendothelial thrombogenicity. Animals fed the SFAED+OLIV showed, compared with the SFAED group, an improved lipid profile with decreased platelet hyperactivity and subendothelial thrombogenicity and less severe morphological lesions of the endothelium and vascular wall. We conclude that supplementation of the SFAED with 15% olive oil reduced vascular thrombogenicity and platelet activation in rabbits. Although the percentage of olive oil in the diet was higher than the amount in the human diet, these results may be helpful in determining the effect of olive oil in the human thrombogenic system.

6-Ketoprostaglandin F1 alpha↗

Olive oil increases the magnitude of postprandial chylomicron remnants compared to milk fat and safflower oil.

OBJECTIVE: The acute effects of olive oil, milk fat and safflower oil on postprandial lipemia and remnant lipoprotein metabolism were investigated. METHODS: Eight Healthy male volunteers randomly underwent three types of oral fat-vitamin A loading tests. The test drink was a mixture of retinyl palmitate (RP)(50,000 IU of aqueous vitamin A/m2 body surface area) and one of the three types of oils (40 g of fat/m2 body surface area): olive oil (70.7% oleic acid of total fatty acids); milk fat (69.3% saturated fatty acid); safflower oil (74.2% linoleic acid). RESULTS: Olive oil significantly increased plasma triacylglycerol and RP concentrations 4 hours after fat loading, as compared to other fats. Increases of remnant like particle concentrations were higher after olive oil than after the other two fats. CONCLUSION: These results show that olive oil increases the magnitude of postprandial chylomicrons and chylomicron remnants compared to milk fat and safflower oil.

Adult↗

Occupational allergic contact dermatitis from olive oil in a masseur.

Contact allergy to olive oil is considered rare. There are 20 cases of contact allergy to olive oil described, and 3 of these had an occupational hand eczema as a result of olive oil. We describe a masseur who was allergic to olive oil, resulting in an occupational hand eczema. Both patch tests and a use test with olive oil was undertaken. An oral provocation with olive oil was also performed. Both patch tests were positive, as was the use test after 2 days. The oral provocation test was negative. Despite contact allergy to olive oil being rare, sensitization occurs. The external use of olive oil should be discouraged, at least in masseurs, when used under occlusion, and in long-standing dermatoses.

Dermatitis, Allergic Contact↗

Potential vasorelaxant effects of oleanolic acid and erythrodiol, two triterpenoids contained in 'orujo' olive oil, on rat aorta.

'Orujo' olive oil is obtained by chemical processes from the waste resulting from the mechanical extraction of virgin olive oil. The aim of the present study was to evaluate a new pharmacological property of two natural triterpenoids contained in olive oil, as vasodilatory agents, and to determine their mechanism of action. The two compounds studied were oleanolic acid and erythrodiol. The vasorelaxant effect induced by these pentacyclic triterpenoids was studied in isolated thoracic rat aorta. Oleanolic acid and erythrodiol, accumulatively added, showed vasorelaxant activities in aortic rings with endothelium pre-contracted by 10(-6) m-phenylephrine (maximum percentage of relaxation 86.38 (sem 2.89) and 73.53 (sem 6.01), respectively). They had almost no relaxant effect on depolarised or endothelium-denuded aortic segments. The relaxation was significantly attenuated by pre-treatment with the NO synthase inhibitor N(omega)-nitro-L-arginine-methylester (L-NAME; 3x10(-4) m). To characterise the involvement of endothelial factors, in addition to NO, arteries with endothelium were exposed to 10(-5) m-indomethacin (INDO), a cyclo-oxygenase inhibitor, or INDO plus L-NAME. INDO did not have any significant effect on the relaxant response of both compounds. The combination of L-NAME plus INDO only abolished the oleanolic acid-induced relaxation. The present results suggest that the mechanism of relaxation seems to be mainly mediated by the endothelial production of NO; however, other mechanisms cannot be excluded. It can be concluded that oleanolic acid and erythrodiol may have interesting therapeutic potential as new vasodilator drugs, thus protecting the cardiovascular system. Therefore, the intake of 'orujo' olive oil, as a source of these compounds, might be beneficial in this regard.

Animals↗

Sunflower oil does not protect against LDL oxidation as virgin olive oil does in patients with peripheral vascular disease.

BACKGROUND & AIMS: The aim of this study was to compare the in vivo effects of a diet rich in virgin olive oil or sunflower oil on the lipid profile and on LDL susceptibility to oxidative modification in free-living Spanish male patients with peripheral vascular disease. METHODS: A total of 20 Spanish male subjects diagnosed with peripheral vascular disease were randomly divided into two groups (n = 10) receiving different supplements, virgin olive oil and sunflower oil for 4 months. RESULTS: The adaptation of patients to the experimental supplements was demonstrated since plasma and LDL fatty acids composition reflected dietary fatty acids. No differences in triglycerides, total cholesterol, LDL-cholesterol or HDL-cholesterol concentrations were found between the groups of patients. A significantly higher LDL susceptibility to oxidation was observed after sunflower oil intake in comparison with virgin olive oil, in spite of an increase in LDL alpha-tocopherol concentration in sunflower oil group. CONCLUSIONS: The results of the present study provide further evidence that sunflower-oil-enriched diets does not protect LDL against oxidation as virgin olive oil does in patients with peripheral vascular disease.

Aged↗