Acids In Plasma Lipids Research Articles

Fatty acid desaturase activity and single nucleotide polymorphism of fatty acid desaturase gene and breast cancer risk in estrogen receptor subtype.

e12551 Background: Breast cancer (BC) is the most common cancer in women. Various mechanisms are known to promote tumourogenesis. Arachidonic acid and its metabolites are one such pathway which promote tumorigenesis by inflammation and angiogenesis. It can be hypothesized that fatty acid metabolism is dysregulated in women with BC. We compared the fatty acid desaturases activity in women with BC and the control women. Breast cancer, which is a diet-related inflammatory disease, is also associated with the plasma concentration of omega fatty acids (n-3 and n-6), and can have an impact of its genetic variants. We studied the association between genetic variant rs174537 of fatty acid desaturase gene 1(FADS 1) and the estrogen receptor positive BC. Methods: Sixty women diagnosed with BC and 40 control women without BC between the age group of 25-60years of age were recruited for comparing the fatty acid desaturases activity. The tumors were classified by Estrogen Receptor (ER) status. Fatty acid Desaturases activities (D5, D6 and D9) were estimated as the ratio of product to precursor of individual fatty acids in plasma lipids. To study the association between genetic variant rs174537 of fatty acid desaturase gene 1(FADS 1) and the estrogen receptor positive BC, we recruited 102 (ER +ve, n = 53; ER -ve,n = 49) women with proven BC, prior to therapy. SNP rs 174537(G > T) showed maximum variability and the strongest genetic determinant in the Genome-wide association study were genotyped using Sanger sequencing. Results: Decreased levels of delta 5 and delta 9 desaturases activity and increased delta 6 desaturase activity were associated with the adverse profile of BC than the control group. Estrogen Receptor status also showed variation in desaturase activity. The highest tertile of Alphalinolenic acid (ALA) showed a significantly reduced association with BC compared to the lowest tertile (OR = 0.2, 95 %CL = 0.1–1.14, P = 0.03). Median values of ALA were higher in GT/TT genotype in ER +ve molecular subtype (P = 0.03) and Docosapentaenoic acid (DPA) was higher in GG genotype of ER -ve molecular subtype (P = 0.037). When both the groups were put together the highest tertile of GG tertile showed significantly reduced association with BC compared with the other lowest tertiles of GG and GT/TT genotypes (OR, 95% CL = 0.45(0.2–0.9). Conclusions: We conclude that unbalanced polyunsaturated fatty acids and impaired fatty acid desaturation plays a role in the pathogenesis of BC. The high levels of arachidonic acid and low levels of n-3 fatty acids result in a pro-inflammatory milieu which might contribute to the pathogenesis of BC. We also conclude that the individuals with genetically determined lower activity of FADS1 (minor allele T) will derive greater advantage from n-3 fatty acids than those with higher FADS1 activity (G allele).

Linoleic acid supplement in cystic fibrosis: friend or foe?

Linoleic acid supplement in cystic fibrosis: friend or foe?

Effects of Marginal Vitamin B6 Deficiency on Plasma Fatty Acid Profiles in Healthy Men and Women

The interaction between vitamin B6 (VB6) and lipid metabolism is not well understood. Previous studies indicated that linoleic acid (LA) levels increased and arachidonic acid (AA) levels decreased in different tissues of VB6‐deficient rats, suggesting an altered n‐6 pathway of fatty acid (FA) synthesis. Our study aimed to determine the effect of marginal VB6 deficiency on plasma FA in human subjects. Thirteen healthy subjects (7 men and 6 women, aged 20–39 yr) received a 2‐d adequate diet followed by a 28‐d VB6 restricted diet (0.5 mg/d) to reach a marginal VB6 deficiency (plasma pyridoxal‐5′‐phosphate 20–30 nM). Fasting blood samples were collected after 2‐d of adequate diet and after 28‐d of VB6 restricted diet. Plasma total FA profiles were analyzed by gas chromatography/flame ionization detection. After 28‐d of VB6 restriction, AA concentration decreased significantly from (mean ± SD) 533 ± 72 nM to 479 ± 59 nM (p=0.004). The conversion indices of AA/LA also significantly decreased from 0.23 ± 0.04 to 0.20 ± 0.04 (p<0.001). There was a slight but non‐significant increase in plasma LA concentration. However, we did not observe any significant alteration in n‐3 fatty acid concentrations. In conclusion, marginal VB6 deficiency is associated with alterations in the distribution of n‐6 fatty acids in plasma lipids in healthy men and women. Supported by NIH grant DK072398 and GCRC grant M01‐RR00082.

Dietary supplementation of obese children with 1000 mg alpha-linolenic acid per day: a placebo-controlled double blind study

Enhanced dietary intake of omega-3 fatty acids may benefit persons with increased cardiovascular risk, among them obese subjects. Incorporation of omega-3 fatty acids into the plasma lipids is a prerequisite to achieve the favorable effects; however, only very few data are available on the dose of omega-3 fatty acid supplementation in children. The aim of our study was to examine the effects of the consumption of a diet supplemented with 1000 mg alpha-linolenic acid daily on plasma lipids in obese children. In this two times six-week-long, placebo-controlled, crossover study, 9 obese children (age: 13.1 [2.5] years, body mass index: 31.2 [6.2] kg/m 2 ), median [IQR]) incorporated into their diet one egg and one meatball (50 g) per day from hens fed diets containing flaxseed oil, i.e. supplementary dietary intake of 1000 mg alpha-linolenic acid per day was provided. The fatty acid composition of plasma lipids was determined by high-resolution gas-liquid chromatography. Tendencies of increase were observed in the alpha-linolenic acid content of plasma lipids in the phospholipid, triacyl-glycerine and sterol-ester fractions after the supplementation with alpha-linolenic acid. In the non-esterified fatty acid fraction, the values of alpha-linolenic acid were significantly higher after the supplementation (0.11 [0.08] versus 0.14 [0.20], % weight/weight, p < 0.05), indicating the beginning of the accumulation of alpha-linolenic acid in plasma lipids. In obese children a six-week-long supplementation of the diet with 1000 mg alpha-linolenic acid per day increased significantly the contribution of omega-3 fatty acids only to the non-esterified fatty acids of plasma lipids, but had no significant effect on the esterified fractions. Increase of the dose of supplementation may be needed to influence omega-3 fatty acid status in obese children.

Characteristics of obese children with low content of arachidonic acid in plasma lipids

Although there have been many studies on the relationship between obesity and long-chain polyunsaturated fatty acid (LCPUFA), the results and their interpretation are controversial, especially in children. Arachidonic acid (AA), the product of n-6 LCPUFA, is reported to be related to insulin resistance. The purpose of the present paper was to investigate the LCPUFA profile in obese children and mechanisms that contribute to reduced AA content. An age- and sex-matched control study was performed. The study subjects were 59 obese children (mean age, 11.8 years) and 53 healthy non-obese children (mean age, 12.5 years). The study parameters included anthropometric measurements, serum lipids, leptin and fatty acid composition in plasma. Plasma fatty acids in obese children had lower linoleic acid (P < 0.0001) and higher dihomo-gamma-linolenic acid (P = 0.0004) than those in non-obese children. In all subjects combined, delta-6 desaturase (D6D) index (ratios of [C 18:3n-6+C 20:2n-6]/C 20:4n-6 or C 20:4n-6/C 18: 2n-6) correlated with leptin (P < 0.0001). There was no significant difference in AA content between obese and non-obese. However, the AA content was low (<mean - 1SD in controls) in 27.1% of obese children, in whom D6D index was not elevated in spite of high insulin concentration. Obese children had changes in plasma LCPUFA profile that indicate upregulation of n-6 LCPUFA metabolism, probably caused by activated D6D activity to compensate AA demand. Heterogeneity of AA content in obese children depends on D6D and delta-5-desaturase activity, which may reflect insulin sensitivity.

Higher plasma docosahexaenoic acid is associated with reduced progression of coronary atherosclerosis in women with CAD

Fish intake, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and in some cases alpha-linolenic acid (ALA) have been associated with reduced risk of cardiovascular events and death. The association between n-3 fatty acids in plasma lipids and the progression of coronary artery atherosclerosis was assessed among women with established coronary artery disease (CAD). A prospective cohort study involved postmenopausal women (n = 228) participating in the Estrogen Replacement and Atherosclerosis Trial. Quantitative coronary angiography was performed at baseline and after 3.2 +/- 0.6 (mean +/- SD) years. Women with plasma phospholipid (PL) DHA levels above the median, compared with below, exhibited less atherosclerosis progression, as expressed by decline in minimum coronary artery diameter (-0.04 +/- 0.02 and -0.10 +/- 0.02 mm, respectively; P = 0.007) or increase in percentage stenosis (1.34 +/- 0.76% and 3.75 +/- 0.74%, respectively; P = 0.006), and had fewer new lesions [2.0% (0.5-3.5%) of measured segments (95% confidence interval) and 4.2% (2.8-5.6%), respectively; P = 0.009] after adjustments for cardiovascular risk factors. Similar results were observed for DHA in the triglycerides (TGs). EPA and ALA in plasma lipids were not significantly associated with atherosclerosis progression. Consistent with higher reported fish intake, higher levels of plasma TG and PL DHA are associated with less progression of coronary atherosclerosis in postmenopausal women with CAD.

87 Anthropometric Indices Indicative of Obesity are Positively Related to N-6 Long-Chain Polyunsaturated Fatty Acids in Plasma Lipids of Obese Children

Introduction: Controversial data were reported in studies on fatty acid composition of plasma lipids in obese subjects (cf. Decsi et al, Lipids 31: 305–311, 1996 and 35: 1179–1184, 2000 to Phinney et al, Am J Clin Nutr 53: 831–838, 1993). The equivocal data obtained in different studies may be related to differences in anthropometric characteristics of the study populations.Subjects and methods: Obese children (n = 114, age: 13 [3.1] years, body weight (BW): 76.6 [20.7] kg, relative body weight (RBW): 165.8 [22.7] %, body mass index (BMI): 41.3 [4.1] kg/m2, body fat (BF): 38.7 [4.0] %, waist/hip ratio: 0.85 [0.07]), mean [SD]) were investigated. Fatty acid composition of plasma lipid classes was determined by high-resolution capillary gas-liquid chromatography.Results: The contribution of n-6 PUFA to the fatty acid composition of plasma sterol esters were as follows: linoleic acid (C18:2n-6, LA): 53.40 [6.19], dihomo-gamma-linolenic acid (C20:3n-6, DHGLA): 0.86 [0.26], arachidonic acid (C20:4n-6, AA): 8.10 [2.83], ratio of gamma-linolenic acid (C18:3n-6, GLA) plus DHGLA to LA: 0.03 [0.01], data are % weight/weight, median [IQR]. Values of LA showed significant and inverse correlation with RBW. In contrast, values of DHGLA showed significant and positive correlations with RBW and BMI, and AA values exhibited significant and positive correlations with BW, BMI and BF (Table). The product/substrate ratios for the delta-6-desaturase enzyme ([GLA+DHGLA]/LA) were significantly and positively related to RBW and to the waist/hip ratio (Table).Table 1 Spearman rank correlation coefficients between anthropometric characteristics and plasma sterol ester fatty acids in 114 obese children. *P < 0.05; **P < 0.001Full size tableConclusions: 1. In the present study, various anthropometric indices indicative of obesity were significantly and positively related to n-6 long-chain polyunsaturated fatty acids in plasma lipids of obese children. 2. The product/substrates ratios for the delta-6 desaturase enzyme indicated enhanced conversion rate with more pronounced obesity. 3. Extent of obesity should be taken into account in studies on fatty acid metabolism in obese subjects.

Polyunsaturated fatty acids in plasma lipids of diabetic children during and after diabetic ketoacidosis

Previously we reported significantly higher plasma values of the essential fatty acids but significantly lower values of their longer-chain metabolites in diabetic children than in healthy controls. Here, we report data on the acute effect of diabetic ketoacidosis (DKA) on the fatty acid composition of plasma lipids. Diabetic children (n=9; age: 16.1 [3.3] y; duration of diabetes: 5.0 [5.3.] y; daily insulin dose: 0.87 [0.66] unit/kg body weight/d; glycated haemoglobin: 13.4 [2.8] %; median [IQR]) were investigated at admission for DKA (during DKA) and at the end of the treatment of DKA (after DKA). Fatty acid composition of plasma lipid classes was determined by high-resolution capillary gas-liquid chromatography. Blood glucose (27.0 [8.5] vs 6.5 [1.6] mmol/l), pH (7.28 [0.35] vs 7.36 [0.06]) and base excess (-8.9 [15.1] vs -2.2 [6.3] mmol/l) were grossly abnormal during but not after DKA. Values of linoleic acid were significantly lower after than during DKA (non-esterifed fatty acids (NEFA): 15.55 [1.47] vs 12.27 [5.74] % wt/wt; triacylglycerols (TG): 20.84 [9.23] vs 17.40 [5.78]; p<0.05). In contrast, values of gamma-linolenic acid (NEFA: 0.87 [0.54] vs 2.34 [1.85]; p<0.05) and arachidonic acid (TG: 1.37 [0.71] vs 1.74 [0.57]; p<0.05) were significantly lower during than after DKA. The product/substrate ratios for delta-6 desaturation were significantly lower during than after DKA. Successful treatment of diabetic ketoacidosis is associated with a significant increase of long-chain polyunsaturated fatty acid values in blood plasma in diabetic children. This observation suggests that disturbances of essential fatty acid metabolism in diabetic children are related not only to diet but to hypoinsulinaemia as well.

Polyunsaturated fatty acids in plasma lipids of diabetic children during and after diabetic ketoacidosis

Polyunsaturated fatty acids in plasma lipids of diabetic children during and after diabetic ketoacidosis

Fatty acid composition of plasma lipids and erythrocytes in adult goats in positive energy balance fed diets containing either olive or corn oil

The hypothesis tested was, that in ruminating goats on positive energy balance the dietary intake of polyunsaturated fatty acids would be reflected in the fatty acid composition of erythrocytes. Eight goats were fed a diet rich in olive oil, supplying 34% the energy requirement for maintenance (NE l). Four animals were given diets containing either olive or corn oil at an energy level of 1.5 times the requirement for maintenance. Each feeding period lasted 21 days. On the last day of each period, plasma and erythrocytes were collected. Feeding of the diet containing corn oil, which is rich in linoleic acid, resulted in a significant increase in the level of linoleic acid in both plasma lipids and erythrocytes. Likewise, feeding of the diet containing olive oil, while the goats were in positive energy balance, produced higher levels of oleic acid in plasma lipids and erythrocytes. The fatty acid composition of plasma lipids was influenced more strongly by dietary unsaturated fatty acids than that of erythrocytes. The concentrations of plasma lipids, including total cholesterol, did not respond to the type of fat during the experimental periods. When the goats were in negative energy balance, they had significantly higher plasma levels of non-esterified fatty acids. The present study demonstrates that dietary unsaturated fatty acids are incorporated into plasma total lipids and erythrocytes, suggesting a partial escape of dietary unsaturated fatty acids from ruminal biohydrogenation. The escape from hydrogenation may ensure the provision to the goat tissues of essential, polyunsaturated fatty acids. It further implies that the composition of ruminant milk and meat can be influenced by the intake of polyunsaturated fatty acids.

Impact of dietary soybean oil versus medium-chain triglycerides on plasma fatty acids in goats

The influence on lipid metabolism of dietary soybean oil with 52.6% linoleic acid (C18:2 n-6), was studied in 2-year-old, male-castrated Dutch white goats. A medium-chain triglycerides-product (MCT) containing 48.9% caprylic (C8:0) and 41.0% capric acid (C10:0) was used as control oil. Six goats were fed the diets containing either soybean oil or MCT according to a 21×21 days cross-over design. The rations contained about 15% crude fat in the dietary dry matter. The soybean oil diet significantly ( P<0.05) increased the absolute amount of linoleic acid in plasma lipids. The plasma contents of heptadecanoic acid (C17:0) and heptadecenoic acid (C17:1) were decreased by feeding the soybean oil diet ( P<0.05). The fatty acid composition of red blood cells was not differently affected by the dietary fats. Dietary soybean oil versus MCT significantly ( P<0.05) increased plasma total cholesterol by 47%, HDL cholesterol by 50% and phospholipids by 39%, but left plasma triglycerides and non-esterified fatty acids unchanged ( P>0.05). This study provides evidence that dietary linoleic acid can escape from biohydrogenation in the rumen of goats and shows that the type of dietary fat has a marked impact on lipid metabolism in goats.

Seasonal Variation in Copper-mediated Low-density Lipoprotein Oxidation In Vitro is Related to Varying Plasma Concentration of Oxidised Lipids in Summer and Winter

The seasonal variation of CuCl 2 -mediated low density lipoprotein (LDL) oxidation (10 w M Cu 2+ , lag phase, rate of oxidation and maximum absorbance at 234 nm) were measured in 43 men and women on 4-6 occasions (mean 5.7 - 0.5 ) over a 12-month period. The lag phase averaged 52.7 - 0.6 min and did not differ by gender. Lag phase and rate of the rapid propagation phase of LDL oxidation showed a sinusoidal pattern over the year (increased and reduced oxidative susceptibility during January and June-July, respectively; both p <0.001 ). Changes in plasma f -tocopherol, ascorbic acid, lycopene or g -carotene concentrations did not explain seasonal differences in oxidative susceptibility of LDL in vitro. Nor did plasma lipid content of linoleic acid, the main substrate of lipid peroxidation, vary. However, the amount of hydroperoxy- plus hydroxy-fatty acids in plasma lipids varied according to season ( p <0.024) and was related to the lag phase ( r = m 0.26, p <0.001). Seasonal variation in oxidative susceptibility was not significant after adjusting for hydroperoxy- plus hydroxy-fatty acids ( p =0.506). Isolated LDL is more vulnerable to Cu 2+ -induced lipid peroxidation during the winter and this may be due to the higher amount of oxidised lipids during that period.

Gemfibrozil lowers plasma lipids and increases polyunsaturated fatty acid content and oxidative susceptibility of lipoproteins in hypertriglyceridemia

Background: Gemfibrozil is an effective drug in the treatment of hypertriglyceridemia and its effects on morbidity and mortality seem out of proportion to its lipid lowering actions. There is considerable interest in its potential effects on lipoprotein fatty acid composition and consequent effect on oxidative susceptibility. Experimental results are not conclusive regarding whether gemfibrozil alters lipid composition or oxidative susceptibility of lipoproteins in humans. Here we investigate this question using different methodology than employed in previous investigations. Methods: Eleven hypertriglyceridemic individuals completed a 12-week course of gemfibrozil therapy (600 mg twice daily) intended to primarily evaluate a new way of assessing lipoprotein susceptibility to oxidation in relation to changes in the fatty acid profile. We measured susceptibility of lipoproteins in the plasma macromolecule fraction to copper-mediated oxidation. In addition, plasma lipids were separated into phospholipid (PL), cholesterol ester (CE) and triglyceride (TG) fractions and the fatty acid composition of these classes determined by gas–liquid chromatography. The relation between changes in lipid concentration, fatty acid composition and oxidative parameters (principally lag time) was examined by correlational analysis. Results: Triglyceride concentrations and total cholesterol concentrations responded appropriately to gemfibrozil (lowered by 55% and 15%, respectively). Polyunsaturated fatty acid (PUFA) proportion increased significantly in cholesterol ester and phospholipid fractions of plasma lipids at the expense of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA). Oxidative parameters also changed significantly. Lag time (LT) and maximal extent of oxidation showed the most significant changes. Lag time, the principle measure of lipoprotein susceptibility to oxidation, was decreased by gemfibrozil. The increase in polyunsaturated fatty acid content in phospholipid and cholesterol ester significantly correlated with decreased lag time. Conclusion: These data support the notion that gemfibrozil increases the proportion of polyunsaturated fatty acids in plasma lipids and that this increase is associated with an increase in lipoprotein oxidative susceptibility as measured by lag time in hypertriglyceridemia.

Inverse association between trans isomeric and long-chain polyunsaturated fatty acids in cord blood lipids of full-term infants

Previous studies showed significant inverse correlations between values of trans isomeric and long-chain polyunsaturated fatty acids in plasma lipids of preterm infants and healthy children aged 1-15 y. We sought to evaluate the same correlations in full-term infants at birth. We studied healthy full-term infants (n = 42) born after normal pregnancies and deliveries. All infants had a family history of atopy (both parents or one of the parents and a sibling had atopic symptoms). The fatty acid composition of venous cord blood lipids was determined by high-resolution capillary gas-liquid chromatography. The mean (+/-SEM) sum of trans fatty acids was 0.49 +/- 0.02% by wt in phospholipids, 2.47 +/- 0.20% by wt in cholesterol esters, 1.73 +/- 0.09% by wt in triacylglycerols, and 1.59 +/- 0.07% by wt in nonesterified fatty acids. Linear correlation analysis showed significant inverse correlations between the sum of trans fatty acids and both arachidonic acid and docosahexaenoic acid in phospholipids (r = -0.56, P < 0.001, and r = -0.48, P = 0.01, respectively), cholesterol esters (r = -0.52, P < 0.001, and r = -0.39, P = 0.018, respectively), and nonesterified fatty acids (r = -0.41, P = 0.007, and r = -0.41, P = 0.006, respectively). Because trans fatty acids in the fetal circulation must originate from the maternal diet, our results indicate that maternal exposure to trans fatty acids may represent a previously neglected variable that inversely influences long-chain polyunsaturated fatty acid status in full-term infants at birth.

Polyunsaturated fatty acids in plasma lipids of obese children with and without metabolic cardiovascular syndrome.

Previously we reported significantly higher values of gamma-linolenic acid (GLA, 18:3n-6), dihomo-gamma-linolenic acid (DHGLA, 20:3n-6), and arachidonic acid (20:4n-6) in plasma lipid classes in obese children than in nonobese controls. In the present study, fatty acid composition of plasma phospholipids (PL) and sterol esters (STE) was determined by high-resolution capillary gas-liquid chromatography in obese children with and without metabolic cardiovascular syndrome [MCS: defined as simultaneous presence of (i) dyslipidemia, (ii) hyperinsulinemia, (iii) hypertension, and.(iv) impaired glucose tolerance] and in nonobese controls. Fatty acid composition of PL and STE lipids did not differ between obese children without MCS and controls. Obese children with MCS exhibited significantly lower linoleic acid (LA, 18:2n-6) values in PL (17.43 [2.36], % wt/wt, median [range from the first to the third quartile]) than obese children without MCS (19.14 [3.49]) and controls (20.28 13.80]). In contrast, PL GLA values were significantly higher in obese children with (0.13 [0.08]) than in those without MCS (0.08 [0.04]), whereas STE GLA values were higher in obese children with MCS (1.04 [0.72]) than in controls (0.62 [0.48]). DHGLA values in PL were significantly higher in obese children with MCS (4.06 [0.74]) than in controls (2.69 [1.60]). The GLA/LA ratio was significantly higher, whereas the AA/DHGLA ratio was significantly lower in obese children with MCS than in obese children without MCS and in controls. In this study, LA metabolism was affected only in obese children with but not in those without MCS. In obese children with MCS, delta6-desaturase activity appeared to be stimulated, whereas delta5-desaturase activity appeared to be inhibited. Disturbances in LA metabolism may represent an additional health hazard within the multifaceted clinical picture of MCS.

Trans Fatty acids in human milk are inversely associated with concentrations of essential all-cis n−6 and n−3 fatty acids and determine trans, but not n−6 and n−3, fatty acids in plasma lipids of breast-fed infants

Human milk fatty acids vary with maternal dietary fat composition. Hydrogenated dietary oils with trans fatty acids may displace cis n-6 and n-3 unsaturated fatty acids or have adverse effects on their metabolism. The effects of milk trans, n-6, and n-3 fatty acids in breast-fed infants are unclear, although n-6 and n-3 fatty acids are important in infant growth and development. We sought to determine the relations between trans and cis unsaturated fatty acids in milk and plasma phospholipids and triacylglycerols of breast-fed infants, and to identify the major maternal dietary sources of trans fatty acids. We collected milk from 103 mothers with exclusively breast-fed 2-mo-old infants, blood from 62 infants, and 3-d dietary records from 21 mothers. Mean (+/-SEM) percentages of trans fatty acids were as follows: milk, 7.1 +/- 0.32%; infants' triacylglycerols, 6.5 +/- 0. 33%; and infants' phospholipids, 3.7 +/- 0.16%. Milk trans fatty acids, alpha-linolenic acid (18:3n-3), arachidonic acid (20:4n-6), docosahexaenoic acid (22:6n-3) (P < 0.001), and linoleic acid (18:2n-6) (P = 0.007) were each related to the same fatty acid in infant plasma phospholipids. Milk trans fatty acids were inversely related to milk 18:2n-6 and 18:3n-3, but not to milk or infant plasma 20:4n-6 or 22:6n-3. trans Fatty acids represented 7.7% of maternal total fat intake (2.5% of total energy); the major dietary sources were bakery products and breads (32%), snacks (14%), fast foods (11%), and margarines and shortenings (11%). There were comparable concentrations of trans fatty acids in the maternal diet, breast milk, and plasma triacylglycerols of breast-fed infants. Prepared foods were the major dietary source of trans fatty acids.

Docosahexaenoic acid and smoking-related chronic obstructive pulmonary disease. The Atherosclerosis Risk in Communities Study Investigators.

If the inflammatory response to inhalation of cigarette smoke causes chronic obstructive pulmonary disease (COPD), suppression of that natural response might be beneficial. We hypothesized that a smoker's risk of developing COPD is inversely related to physiologic levels of two fatty acids that have antiinflammatory properties: eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6). The proportion of each fatty acid in plasma lipids was measured in 2,349 current or former smokers. COPD was identified and defined by clinical symptoms and/or spirometry. After adjustment for smoking exposure and other possible confounders, the prevalence odds of COPD were inversely related to the DHA (but not to the EPA) content of plasma lipid components in most of the models. For example, as compared with the first quartile of the DHA distribution, the prevalence odds ratios (ORs) for chronic bronchitis were 0.98, 0.88, and 0.69 for the second, third, and fourth quartiles, respectively (p for linear trend = 0.09). The corresponding ORs for COPD as defined spirometrically, were 0.65, 0.51, and 0.48 (p < 0. 001). Among 543 current heavy smokers, adjusted mean values of FEV1 (lowest to highest DHA quartile) were 2,706, 2,785, 2,801, and 2,854 ml. DHA may have a role in preventing or treating COPD and other chronic inflammatory conditions of the lung. Pilot testing of that hypothesis in experimental models seems warranted.

Vegetarians and Cardiovascular Risk Factors: Hemostasis, Inflammatory Markers and Plasma Homocysteine

We studied hemostatic and inflammatory cardiovascular risk factors (CVRF), and total plasma homocysteine (tHcy) in 26 vegetarians (23 lacto- or ovolactovegetarians and 3 vegans), matched by age, sex and socioeconomic status with omnivorous controls. Vegetarians had significantly lower proportion of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids in plasma lipids, significantly shortened bleeding time, and increased blood platelet count and in vitro platelet function (aggregation and secretion). Plasma levels of all coagulation or fibrinolytic factors and natural inhibitors synthesized in the liver were lower in vegetarians than in controls. Whereas for some factors this decrease was statistically significant (fibrinogen, factor VIIc, antithrombin III, protein S, plasminogen) for the remaining (factors VIIIc, Vc, prothrombin, protein C) a trend in the same direction was found. For hemostatic proteins of predominantly extrahepatic origin (von Willebrand factor. tPA, PAI-1) this tendency was not present. No significant differences in inflammatory proteins (C-reactive protein and alpha1-protease inhibitor) were detected in both groups. tHcy was significantly increased in vegetarians, and correlated only with cobalamin levels. The increased platelet function and tHcy found in vegetarians may counteract the known cardiovascular health benefits of vegetarian diet (VD).

Long Chain Polyunsaturated Fatty Ac Synthesis Using Deuterated Precursors in Preterm, Term and Growth Retarded Neonates • 1568

In vivo elongation and desaturation of linoleic acid (LA) to arachidonic acid (ARA) and a-linolenic (LNA) to docosahexaenoic acid (DHA) was studied in 15 preterm (bw 1740g, GA 31.3 wks), 8 term (bw 3557g, GA 40.1 wks) and 11 growth retarded (IUGR) (bw 1834, GA 35.6) neonates. They received 50 mg/kg bw of LA & LNA labeled with 5 deuterium (d5) enterally during the first days of life. D5 labeled derivatized fatty acids were determined in blood samples at 24,48 and 96 hrs after dosing. Lipids were extracted and fatty acid analyzed by GC and negative ion mass spectrometry HP 5989GCMS. Mean concentrations (mg/ml) and d5/d0 n-3 and n-6 fatty acids in plasma lipids are reported in the table, variability is high. d5 LA and LNA peaked at 24 hrs, d5 ARA & d5DHA were highest at 48 hours in term infants and at 96 hrs in preterm and IUGR infants. Our results suggest a slower rate of LCPUFA production in IUGR. Preterms had highest concentrations of d5 LCPUFA and d5/d0 at all times suggesting increased conversion. Neonates are able to produce LCPUFA, immature infants produce them faster.

Blood pressure and atherogenic lipoprotein profiles of fish-diet and vegetarian villagers in Tanzania: the Lugalawa study

There is evidence that populations with a high intake of fish, and specifically fish oils, are at reduced risk of cardiovascular disease. To explore the effect of fish intake, we compared two groups of Bantu villagers in Tanzania; one group live on the shores of Lake Nyasa and their diet includes large amounts of freshwater fish; the other group live in the nearby hills and have a vegetarian diet. We carried out a cross-sectional study of 622 fish-consuming villagers and 686 vegetarian villagers. 618 (99.4%) and 645 (94.0%), respectively, agreed to take part. Anthropometric and self-reported medical history data were collected by one local physician and a medical assistant, who also measured blood pressure and took blood samples for measurement of plasma lipids. A dietary questionnaire was administered to 25 families (about 15% of the study population) in each village. After adjustment for age, sex, and alcohol intake the fish-consuming group had lower mean blood pressure than the vegetarian group (123/72 vs 133/76 mm Hg, p < 0.001). The frequencies of definite and borderline hypertension (by WHO criteria) were lower in the fish-consuming than in the vegetarian group (2.8 vs 16.4%; 9.7 vs 22.3%, respectively). Plasma concentrations of total cholesterol (mean 3.53 [SD 1.04] vs 4.10 [1.04] mmol/L), triglycerides (0.92 [0.64] vs 1.31 [0.64] mmol/L), and lipoprotein(a) (201 [213] vs 321 [212] mg/L), were all lower (p < 0.0001) in the fish-consuming group than in the vegetarian group. The proportions of n-3 polyunsaturated fatty acids in plasma lipids were higher (p < 0.0001) in the fish-consuming group than in the vegetarian group (eicosapentaenoic acid 2.3 [1.3] vs 0.7 [0.2]%; docosapentaenoic acid 1.1 [0.4] vs 0.6 [0.3]%; docosahexaenoic acid 5.7 [1.6] vs 1.5 [1.1]%). In these villagers, consumption of freshwater fish (300-600 g daily) was associated with raised plasma concentrations of n-3 polyunsaturated fatty acids, lower blood pressure, and lower plasma lipid concentrations.