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Nitroalkene derivatives of linoleic acid (nitrolinoleic acid; LN[O.sub.2]) and nitro-oleic acid (OA-N[O.sub.2]) are endogenous lipid products with potent anti-inflammatory properties. The present study was undertaken to evaluate the therapeutic potential of OA-N[O.sub.2] in a mouse model of renal ischemia-reperfusion (I/R) injury. B6129SF2/J mice were subjected to bilateral renal ischemia for 30 min, followed by 24 h of reperfusion. Fifty minutes after ischemia, mice received intraperitoneal (ip) injections of OAN[O.sub.2] (500 [micro]g/kg; I/R OA-N[O.sub.2]), vehicle for OA-N[O.sub.2] (i.e., 0.8 ml/kg ethanol; 1/R veh), or oleic acid (500 [micro]g/kg; I/R OA) every 6 h during the 24-h recovery period. A sham-operated group was not subjected to ischemia and received 0.8 ml/kg ethanol ip every 6 h during the 24-h recovery period (sham veh). While plasma urea and creatinine were elevated (P < 0.05) in I/R veb vs. sham veh mice, the severity was less (P < 0.05) in I/R OA-N[O.sub.2] animals. Indices of histological damage, polymorphonucleocyte infiltration, together with expression of intracellular adhesion molecule-I, interleukin-l[beta], and tumor necrosis factor-[alpha], [p47.sup.phox], and [gp91.sup.phox] were greater in I/R veh vs. sham veh mice, but were attenuated (P < 0.05) in I/R OA-N[O.sub.2] animals. Because indices of renal dysfunction were similar between I/R veh and I/R OA mice (P > 0.05), but less (P < 0.05) in I/R OA-N[O.sub.2] animals compared with both groups, protection from bilateral renal ischemia is afforded by the nitrated but not free form of oleic acid. Together, delayed administration of nitrated fatty acid OA-N[O.sub.2] attenuates renal I/R injury in the mouse likely via inhibition of the inflammatory response. nitrated fatty acids; acute renal failure; inflammation

Postprandial lipemia impairs endothelial function possibly via an oxidative stress mechanism. A stearic acid-rich triacylglycerol (TAG) (shea butter) results in a blunted postprandial increase in plasma TAG compared with an oleic acid-rich TAG; however, its acute effects on endothelial function and oxidative stress are unknown. A randomized crossover trial (n = 17 men) compared the effects of 50 g fat, rich in stearic acid [shea butter blend (SA)] or oleic acid [high oleic sunflower oil (HO)], on changes in endothelial function [brachial artery flow-mediated dilatation (FMD)], arterial tone [pulse wave analysis (PWA), and carotid-femoral pulse wave velocity ([PWV.sub.c-f])], and oxidative stress (plasma 8-isoprostane F2[alpha]) at fasting and 3 h following the test meals. The postprandial increase in plasma TAG was lower (66% lower incremental area under curve) following the SA meal [28.3 (9.7, 46.9)] than after the HO meal [83.4 (57.0, 109.8); P < 0.001] (geometric means with 95% CI, arbitary units). Following the HO meal, there was a decrease in FMD [-3.0% (-4.4, -1.6); P < 0.001] and an increase in plasma 8-isoprostane F2[alpha] [10.4ng/L (3.8, 16.9); P = 0.005] compared with fasting values, but no changes followed the SA meal. The changes in 8-isoprostane F2[alpha] and FMD differed between meals and were 14.0 ng/L (6.4, 21.6; P = 0.001) and 1.75% (0.10, 3.39; P = 0.02), respectively. The reductions in PWA and PWV c-f did not differ between meals. This study demonstrates that a stearic acid-rich fat attenuates the postprandial impairment in endothelial function compared with an oleic acid-rich fat and supports the hypothesis that postprandial lipemia impairs endothelial function via an increase in oxidative stress.

Numerous studies have shown that high olive oil intake reduces blood pressure (BP). These positive effects of olive oil have frequently been ascribed to its minor components, such as [alpha]-tocopherol, polyphenols, and other phenolic compounds that are not present in other oils. However, in this study we demonstrate that the hypotensive effect of olive oil is caused by its high oleic acid (OA) content ([approximately equal to] 70-80%). We propose that olive oil intake increases OA levels in membranes, which regulates membrane lipid structure ([H.sub.II] phase propensity) in such a way as to control G protein-mediated signaling, causing a reduction in BP. This effect is in part caused by its regulatory action on G protein-associated cascades that regulate adenylyl cyclase and phospholipase C. In turn, the OA analogues, elaidic and stearic acids, had no hypotensive activity, indicating that the molecular mechanisms that link membrane lipid structure and BP regulation are very specific. Similarly, soybean oil (with low OA content) did not reduce BP. This study demonstrates that olive oil induces its hypotensive effects through the action of OA. aorta | fatty acids | membrane structure | signaling proteins | membrane-lipid therapy

Fats enriched with rapeseed oil (oleic and linolenic acids) appear to be equally effective in reducing plasma cholesterol and LDL cholesterol compared with butter/grapeseed oil, according to research designed to assess a more satisfactory effect on plasma lipoprotein profile of spreads based on dairy fat. There was a 7% fall in plasma cholesterol through replacing butter/grapeseed oil with rapeseed oil enriched fats. This is a significant result, given that it is widely assumed that a 1% fall in plasma cholesterol leads to a 2% fall in CDH risk.

The hypercholesterolemic effects of a dietary exchange between palmitic acid and oleic acid while linoleic acid is relatively lower in aged women with initially high serum cholesterol and low density lipoprotein cholesterol levels and with high intakes of dietary cholesterol were investigated. Participants were assigned to two consecutive 28-day periods in which they consumed sunflower oil diets rich in palmolein or oleic acid. Results showed that palmolein increased low density lipoprotein cholesterol levels and protected low density lipoproteins against peroxidation than did oleic acid.

The high consumption of olive oil by people in Mediterranean countries may contribute to the lower incidence of coronary heart disease. The fatty-acid composition of olive oil includes oleic acid content in ranges from 56% to 84%. Recent findings show the high intake of oleic acid with lower consumption of saturated fat may be one of the major determining factor in low coronary heart disease rates in those with Mediterranean diets.

Substitution of high oleic acid sunflower oil for herring oil in formulated salmonid diets affected the fatty acid composition of muscle, liver and visceral fat from coho salmon (Oncorhynchus kisutch) and rainbow trout (O. mykiss). Fish were fed diets containing either high oleic acid sunflower oil or herring oil as the supplemental lipid source (12.4 g/100 g diet) for 1-2 mo. Muscle from fish fed the sunflower oil diet had twice the concentration of oleic acid ([approximately] 25 g/100 g lipid) as muscle from fish fed the herring oil diet ([approximately] 12 g/100 g lipid). The maximum concentration of oleic acid in the muscle was obtained after only 2 wk of feeding the sunflower oil diet. Oleic acid concentrations in liver and visceral fat of fish fed the sunflower oil diet were significantly higher than in fish fed the herring oil diet. Rainbow trout fed the sunflower oil diet for 4 wk maintained the higher oleic acid concentrations in muscle and liver when deprived of feed for 2 wk compared with fish fed the herring oil diet. These data indicated that accumulation of oleic acid in coho salmon and rainbow trout muscle was fairly rapidly achieved when a high oleic acid diet was fed. The differences between the fish receiving the two dietary treatments in fatty acid composition and in concentrations of thiobarbituric acid-reactive substances in muscle stored at refrigerated temperatures were consistent with previously reported differences in aroma perceived by a sensory panel. INDEXING KEY WORDS: * coho salmon * fatty acid composition * rainbow trout * oleic acid

Although selenium or vitamin E deficiencies or changing from cereal-based to purified diets augments paraquat toxicity, the action of other dietary components in normal animals fed nutritionally adequate diets is not clear. Upon injection of mice with anti-inflammatory agents, a protective action of the corn oil vehicle against paraquat lethalities was noted. This preventive action of a large parenteral administration of unknown components in oils served as the basis for this study. Intramuscular injection of various vegetable oils protected similarly, indicating that in mixtures, the degree of lipid saturation did not seem to be an important factor. Injection of the monounsaturated fatty acid oleic acid decreased oral paraquat lethalities in mice, but linoleic, gamma-linoleic or linolenic acids were not protective in either male or female mice. Measurement of paraquat concentrations in various tissues at various times after administration indicated no effect of corn oil on paraquat distribution. Although the exact mechanism of the complex nature of oil protection against paraquat toxicity in mice is still unknown, this study provides evidence for in vivo oxidant protection by a monounsaturated fatty acid.

A high-oleic-acid peanut breeding line was used in a study designed to determine the effects of feeding swine diets containing elevated levels of monounsaturated fatty acids as a means to increase the level of monounsaturates and total unsaturates int he resulting carcass fat. Forty-eight pigs were allotted to four treatments that consisted of corn-soybean meal diets that contained 1) high-oleic peanuts (HOP), 2) regular commercial peanuts (RP), or 3) canola oil (CO), each added at a dietary level to provide 10% added fat/oil, and 4) a control diet with no added fat/oil. The oil of HOP averaged 75% oleic acid vs 60% for CO and 53% for RP. The pigs were fed the experimental diets from 33 to 102 kg BW, after which all pigs were slaughtered. All three dietary oil sources resulted in increases (P < .01) of monounsaturates in the backfat; the HOP diet resulted in the greatest increase (32% greater than control). Both CO and RP increased (P < .01) the level of polyunsaturates by nearly twofold; HOP resulted in a small decrease. Total unsaturates increased (P < .01) by 24, 24, and 27% for HOP, RP, and CO treatments, respectively, over that obtained from the control treatment. Carcass fat was softer/oilier (P < .05) from pigs fed CO and RP diets, but not from those fed HOP diets, compared with carcass fat of pigs fed the control diet. Dietary fat/oil source had no effect (P > .05) on other carcass compositional traits and various meat quality attributes. Dietary fat/oil source also had no effect (P > .05) on taste panel evaluations of broiled loin chops and fried bacon; however, a high incidence of off-flavor was noted for bacon from pigs fed CO and to a lesser extent from pigs fed RP, but not from HOP or control pigs. The HOP increased the level of unsaturates in pork fat and there were essentially no detrimental effects on carcass and meat quality characteristics.

Meat from such monogastric animals as swine can be modified to substitute monounsaturated fatty acids for saturated fatty acids. Because monounsaturated fatty acids have a beneficial effect on serum lipids as compared with saturated fatty acids, the objective of this study was to assess the effect of modified pork as compared with regular pork on serum and hepatic lipids. Guinea pigs were fed diets containing pork from control diet-fed hogs or from hogs fed a diet containing high oteic acid sunflower oil. The pork provided almost all of the fat in the diets at the level of 4 and 15 g/100 g diet, 10 or 34% energy. The high oleic pork muscle and fat contained 26 and 46% less palmitic and stearic acids (the primary saturated fatty acids), respectively, and 31 and 29% more oleic acid (the primary monounsaturated fatty acid) than the regular pork muscle and fat, respectively. Cholesterol concentration of diets ranged from 0.06 to 0.08% of the diet. Although total serum cholesterol, HDL cholesterol and triglyceride concentrations did not differ due to type of pork, results indicated that serum LDL cholesterol was lower (15%) and hepatic cholesterol was greater (15%) in the high oleic pork, 15% fat group as compared with the control pork 15% fat group. Also, serum LDL cholesterol concentration was higher in the groups fed 15% fat compared with those fed 4% fat. in this study pork modified to have more oleic acid and less saturated fatty acids had a positive effect on tissue lipids when fed to animals. J. Nutr. 122: 1855-1861, 1992. INDEXING KEY WORDS: * monounsaturated fat * guinea pigs * pork * oleic acid * cholesterol, Guinea pigs were fed pork with a high oleic acid to determine if monounsaturated fatty acids had beneficial effects. Serum cholesterol and liporotein profiles and liver tissue studies were analyzed. Results showed that dietary fat intake did not affect high density lipoprotein levels in guinea pigs although receptor number and binding were enhanced. Similarly, low density lipoproteins remained constant with low fat, high oleic acid intake. A 15% fat diet increased hepatic cholesterol levels in olive oil against lard-fed animals. These findings may have beneficial effects when applied to human diets.

Abstract Oleic acid is a monounsaturated fatty acid with a known action of penetration enhancer which has been used for various purposes, such as a tanning increaser. Narrow-band ultraviolet B [...]

Monounsaturated oils, virgin olive oil (VOO) and high oleic sunflower oil (HOSO) are suggested to have selective physiologic effects on humans in the fasting state. The aim of the study was to evaluate whether two oils with equal amounts of oleic acid but with different compositions of minor fatty acids and triacylglycerol molecular species (TAG) could produce different triacylglycerol-rich lipoprotein (TRL)-TAG responses in the postprandial state. Eight normolipidemic men consumed the following three meals in random order on separate occasions with 2 wk between meals: control meal, control meal plus VOO and control meal plus HOSO. Plasma total TAG and TRL-TAG were measured hourly for 7 h after ingestion. TAG and sn-2 positional fatty acids within TAG were analyzed in the TRL fraction. Plasma total TAG concentrations in response to the dietary oils did not differ. However, TRL triglyceridemia was significantly lower after VOO intake (P [is less than] 0.05). The molecular species in the TRL fraction returned toward basal levels more quickly (P [is less than] 0.05) after VOO than HOSO intake. 2-Positional fatty acid analysis demonstrated higher proportions of stearic and palmitic acids and a lower proportion of oleic acid (P [is less than] 0.05) in TRL-TAG derived from HOSO. This study shows that VOO intake results in attenuated postprandial TAG concentration and faster TRL-TAG disappearance from blood compared with HOSO, suggesting that the oleic acid content may not be the main factor affecting TAG metabolism. Minor fatty acids such as linoleic acid and the 2-positional distribution of saturated stearic and palmitic acids into the TAG molecule may be important determinants of postprandial lipemia in normolipidemic men. J. Nutr. 131: 59-65, 2001. KEY WORDS: * monounsaturated oils * triacylglycerol * postprandial * minor fatty acids * humans

Increasing the ratio of oleic to linoleic acid (O/L) in peanut (Arachis hypogaea L) significantly improves the nutritional and quality attributes of the crop. In currently grown cultivars, the O/L ratio ranges from 0.8 to 2.5. Variation in peanut for O/L ratio has been characterized, and the O/L ratio is digenically inherited at two loci designated as [Ol.sub.1] and [Ol.sub.2]. Previous research has been conducted with Virginia- and runner-type peanut; however, there have been no reports regarding the inheritance and allele frequency at these loci in Spanish-type peanut. The objectives of this study were to determine if the inheritance of the high oleate trait in Spanish-type peanut is similar to that previously reported and to determine the allelic composition of Spanish-type peanut at [Ol.sub.1] and [Ol.sub.2]. Six different Spanish-type peanut cultivars (low oleate) were hybridized with F435-2--2 (high oleate). [F.sub.2] and [BC.sub.1][F.sub.1] progenies were evaluated for the O/L ratio. Segregation patterns indicated that high oleic acid content is digenically inherited in Spanish-type peanut, but there seems to be more allelic variation both within and among these cultivars. In addition, variation within the high and low oleate ratio classes indicated that other factors may be involved in determining the precise O/L ratio., PEANUT is a globally important protein and oilseed crop. In the USA, peanut is used primarily for food, but throughout the rest of the world, it is utilized as an [...]

Two experiments were conducted to determine effects of oleamide on feed intake and ruminal fatty acids when the oleamide was introduced in the feed vs through a ruminal fistula (Exp. 1) or the oleamide was fed for an extended (9-wk) length of time (Exp. 2). In Exp. 1, four nonlactating Holstein cows, each fitted with a ruminal cannula, were fed four diets in a 4 x 4 Latin square design. Each period lasted 2 wk. Diets consisted of 48% corn silage and 52% concentrate on a DM basis. One diet contained no added fat (control) and a second diet contained 4.2% oleic acid. The remaining two diets were designed to expose cows to 4.2% amide (as oleamide) either through the feed (AF) or by administering oleamide into the rumen (AR) each day through the ruminal cannula. The AF diet reduced DMI similarly to results reported previously for lactating dairy cows and sheep. Intake of the oleic acid diet was intermediate between the control and AF diets. Dry matter intake was reduced by AR similarly to the AF diet. The acetate:propionate ratio in samples of ruminal contents was reduced by oleic acid but not by AF or AR. In Exp. 2, 12 steers were divided into three equal groups of two Angus and two Simmental x Angus crosses, and each group was assigned a diet containing either no added fat (control), 4% oleamide, or 4% high-oleic canola oil. All steers had ad libitum access to feed and water. Dry matter intake by steers fed the canola oil diet was not different from that by steers fed the control diet when averaged over the first 3 wk, the last 3 wk, or over the entire 9-wk study. Oleamide reduced DMI 4 kg/d over the first 3 wk of the study. However, DMI of the oleamide diet consistently increased over the 9-wk study, resulting in wk 7 to 9 DMI that was not different from that of steers fed the control diet. These results show that the reduction in feed intake when oleamide is added to cattle rations can be attributed more to physiological responses than to an undesirable unique taste or odor of the oleamide. In finishing beef steers, the decreased intake induced by oleamide was most severe during the first 1 or 2 wk of feeding but gradually lessened over time until it nearly returned to normal by wk 9. Key Words: Amides, Cattle, Fatty Acids, Feed Intake, Oleic Acid, Rumen

Studies show that an increase in oleolyethanolmide helps to reduce food intake. O leic acid, in turn, may affe ct OEA levels, when taken at pharmacological doses . Research in satiety and weight gain are discussed.