Eicosapentaenoic acid and docosahexaenoic acid synergistically attenuate bile acid-induced hepatocellular apoptosis

Background: Clinical studies have demonstrated improvement of parenteral nutrition (PN)–associated liver disease (PNALD) with ω3 polyunsaturated fatty acid (ω3PUFA) supplementation containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Experiments were designed to test the following hypotheses: (1) therapeutic effects of ω3PUFA are due to attenuation of cellular apoptosis induced by hydrophobic bile acid exposure, which occurs in cholestasis, and (2) attenuation of apoptosis by EPA and DHA is additive or synergistic. Methods: Cultured HepG2 cells were treated with 50–200 µM chenodeoxycholic acid (CDCA) in the presence and absence of EPA, DHA, or EPA + DHA. Apoptosis was evaluated using cell staining with fluorescence microscopy and the Apo‐ONE Homogeneous Caspase‐3/7 assay. Specific apoptotic mediators were evaluated with quantitative RT‐PCR. Results: Treatment with EPA alone and DHA alone resulted in 22% and 9% attenuation of caspase‐3/7 activity, respectively. Caspase‐3/7 activity was attenuated by 52% when cells were treated with a combination of EPA and DHA (P = .0034). Treatment with EPA alone, DHA alone, and the combination of EPA and DHA all resulted in equal attenuation of apoptotic mediator gene expression. Conclusions: The combination of EPA and DHA resulted in a synergistic attenuation of bile acid–induced hepatocellular apoptosis, as assessed by caspase‐3/7 activity, compared to EPA and DHA separately. The combination of EPA and DHA did not result in a synergistic attenuation of the upregulation of Fas or TRAIL‐R2. These data suggest that EPA and DHA may be working via multiple intracellular pathways to attenuate bile acid–induced apoptosis.     

Alterations in circulating fatty acid composition in patients with systemic lupus erythematosus: a pilot study

Introduction: Circulating fatty acids (FAs) may play a role in the disease pathogenesis of patients with systemic lupus erythematosus (SLE). Objectives: To compare red blood cell (RBC) and plasma FA composition: (1) between female SLE patients and age‐matched healthy female (HF) controls and in SLE with history of cardiovascular disease (CVD) and those with no history (SLE+CVD vs SLE–CVD); and (2) between SLE patients who were or were not receiving prednisone treatment at the time of blood sampling. Methods: This cross‐sectional study consisted of 33 female patients with SLE (11 SLE+CVD, 22 SLE?CVD) and 20 HF controls. Demographics, CVD risk, medication profile, blood biochemistry, and FA composition of RBC and plasma total lipids were determined. Results: Waist circumference and body mass index were higher in SLE patients than in HF controls. These variables along with serum triglycerides, blood glucose, and systolic blood pressure were higher in SLE+CVD than SLE?CVD patients. RBC FA composition showed lower eicosapentaenoic acid (EPA, ω‐3 active metabolite) and ω‐3 index (EPA+ docosahexaenoic acid) in SLE patients compared with HF controls. The ratio of the RBC inflammatory metabolite, arachidonic acid, to the anti‐inflammatory metabolite EPA was also significantly higher in SLE patients than in HF controls. No differences were seen in plasma FA between SLE and HF groups. However, SLE?CVD patients had a more favorable lipid profile than SLE+CVD patients. In SLE patients, the use of prednisone resulted in alteration of both RBC and plasma FA composition. Conclusion: SLE patients, regardless of their history of CVD, have altered plasma and RBC FA composition favoring inflammation. The use of prednisone was associated with differences in FA profile.     

Effect of Dietary Fatty Acid Composition on Th1/Th2 Polarization in Lymphocytes

Background: It has become increasingly clear that polyunsaturated fatty acids (PUFAs) have immunomodulatory effects. However, the intake of these fatty acids used in animal studies often greatly exceeds dietary human intake. Whether differences in the composition of fatty acids that are consumed in amounts consistent with normal dietary intake can influence immune function remains uncertain. Methods: We manufactured 3 types of liquid diet, related to modified fatty acid composition (ω‐6/ω‐3 = 0.25, 2.27 and 42.9), but excluding eicosapentaenoic acid and docosahexaenoic acid, based upon a liquid diet used clinically in humans. We assessed CD3‐stimulated cytokine production of splenocytes in female BALB/c mice (n = 4 per group) fed 1 of 3 liquid diets for 4 weeks. We also measured the cytokine production of peripheral blood mononuclear cells stimulated with phorbol myristate acetate and ionomycin in humans at the end of a 4‐week period of consumption of 2 different liquid diets (ω‐6/ω‐3 = 3 and 44). Results: We found that the ratio of interfero ω‐γ (IFN‐γ) / interleukin‐4 (IL‐4) was significantly higher in mice fed theω ‐3 rich diet than in others. In humans, IFN‐γ / IL‐4 was significantly higher after the ω‐3 versus the ω‐6 enhanced diet. Conclusions: Differences in the composition of ω‐3 andω ‐6 PUFAs induces a shift in the Th1/Th2 balance in both mouse and human lymphocytes, even when ingested in normal dietary amounts. An ω‐3 rich diet containing α‐linolenic acid modulates immune function.     

Fat content and fatty acid compositions of 34 marine water fish species from the Mediterranean Sea

Fish is the best source of polyunsaturated fatty acids (PUFA), specifically n-3 fatty acids, especially eicosapentaenoic acid and docosahexaenoic acid. The objective of the present study was to determine the fat content and fatty acid compositions of 34 marine water fish species from the Mediterranean Sea. The fatty acid compositions of fish consisted of 30.10–46.88% saturated fatty acids, 11.83–38.17% monounsaturated fatty acids and 20.49–49.31% PUFA. In most species, the following fatty acids were identified: mystiric acid (C14:0, 0.72–8.09%), pentadecanoic acid (15:0, 0.05–2.35%), palmitic acid (C16:0, 15.97–31.04%), palmitoleic acid (C16:1, 1.48–19.61%), heptadecanoic acid (C17:0, 0.31–1.84%), cis-10-heptadecenoic acid (C17:1, 0.17–2.01%), stearic acid (C18:0, 2.79–11.20%), oleic acid (C18:1n9, 2.44–28.97%), linoleic acid (C18:2n-6, 0.06–3.48%), arachidonic acid (C20:4n-6, 0.12–10.72%), cis-5,8,11,14,17-eicosapentaenoic acid (C20:5n-3, 1.94–10%) and cis-4,7,10,13,16,19-docosahexaenoic acid (C22:6n-3, 3.31–31.03%). The proportions of n-3 PUFA ranged from 12.66% for annular seabream to 36.54% for European hake, whereas the proportions of PUFA n-6 were between 1.24% for oceanic puffer and 12.76% for flathead mullet. The results of this study show that these fish species were rich in n-3 PUFA, especially, eicosapentaenoic acid and docosahexaenoic acid.     

Dietary conjugated linoleic acid and long-chain n-3 fatty acids in mammary and prostate cancer protection: a review

The role of dietary fatty acids on cancer is still controversial. To examine the current literature on the protective role of conjugated linoleic acid (CLA) and marine long-chain fatty acids [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] and the risk of breast and prostate cancer, data from 41 case-control and cohort studies and relevant in vitro and animal experiments were included in this 2000–2010 revision. Epidemiological studies on CLA intake or its tissue concentration related to breast and prostate tumorigenesis are not conclusive; EPA and DHA intake have shown important inverse associations just in some studies. Additional research on the analysed association is required.     

ω-3 Fatty acids have no impact on serum lactate levels after major gastric cancer surgery

Background: Preoperative and intraoperative nutrition support in patients undergoing major surgery results in decreased incidence of morbidity and mortality. Studies investigating the role of ω‐3 fatty acids in these patients are increasing. Some are focused on perfusion at the cellular level. This study was undertaken to address the effect of postoperative administration of ω‐3 fatty acids on cellular hypoperfusion associated with major gastric surgery. Methods: Twenty‐six patients undergoing gastric cancer surgery were randomly assigned to receive parenteral nutrition (PN) supplemented with a combination of ω‐6 and ω‐3 fatty acids (Omegaven, 0.2 g/kg/d; Lipovenoes 10%, 0.6 g/kg/d) or with ω‐6 fatty acid (Lipovenoes 10%, 0.8 g/kg/d) for 5 days. Blood samples were taken preoperatively, postoperative day 1, and on the last day of PN therapy (day 5). Results: Patients receiving ω‐3 and ω‐6 fatty acids showed neither lower serum lactate levels nor lower rates of complications compared with patients receiving ω‐6 only. There were no statistically significant differences between the groups in other biochemical parameters, complications, or length of hospital stay or mortality. Conclusion: PN with ω‐3 fatty acid supplementation does not have a significant impact on cellular hypoperfusion and lactate clearance after major gastric surgery.     

Systematic review of fatty acid composition of plasma phospholipids of venous cord blood in full-term infants

Summary The purpose of this review was to systematically evaluate the variability of the fatty acid composition of venous cord blood phospholipids in different populations. In an attempt to review published evidence systematically, we found 19 data sets describing fatty acid composition of venous cord blood phospholipids in 11 European and 2 American countries. The amount of saturated-, monounsaturated- and parent essential polyunsaturated fatty acids exhibited relatively moderate variability among the data sets reviewed. Values of arachidonic acid and docosahexaenoic acid showed two-fold variability among the data sets. The highest values of docosahexaenoic acid were observed in countries with apparently higher consumption of dietary fat from sea fish. Considering the differences in blood sampling, laboratory methods and data presentation, we conclude that fatty acid composition of venous cord blood phospholipids in healthy, full-term infants shows relatively modest variability; hence, it is suitable for the estimation of in utero fatty acid supply. Received: 16 April 2002, Accepted: 16 April 2002     

Is it prudent to add n-3 long-chain polyunsaturated fatty acids to paediatric enteral tube feeding?

Nutritional support, as complete enteral tube feeding, is needed by many paediatric patients and must provide sufficient nutrients for normal growth and development. Enteral feeds contain the parent essential fatty acids, linoleic acid and α-linolenic acid, but often do not contain n-3 long-chain polyunsaturated fatty acids. Available data suggest that biosynthesis of eicosapentaenoic acid and docosahexaenoic acid from α-linolenic acid is low in humans and varies between individuals. Long-term enteral feeding with formulae devoid of eicosapentaenoic acid and docosahexaenoic acid may result in low levels in plasma and tissues, potentially affecting immune and neurological function. Currently there is insufficient evidence to define the quantitative eicosapentaenoic acid and docosahexaenoic acid requirements for healthy children, or those with various disease states. Nevertheless, it appears prudent to supply children on long-term enteral nutrition with a dietary source of eicosapentaenoic acid and docosahexaenoic acid. A reasonable approach would be to provide amounts matching intakes of healthy children complying with the advice to consume 1-2 portions of oily fish per week. Further studies are needed to investigate the effects of different amounts of eicosapentaenoic acid and/or docosahexaenoic acid in enteral nutrition on polyunsaturated fatty acid status and the functional and clinical consequences in children.     

A tutorial on fatty acid biology

Fatty acids are an extraordinarily diverse set of molecules that serve as sources of fuel, key components of cell structure, and parent molecules for bioactive second messengers. The metabolism of fatty acids is part of a delicate homeostasis that is fundamental to normal functioning and the response to pathophysiologic insult. The growing body of evidence on nutrition demonstrates that we truly "are what we eat," and the fatty acid content of our diets has far-reaching physiologic implications, many of which we are only beginning to understand. As the gap between basic science and patient care becomes increasingly narrow, clinicians should have a working knowledge of fatty acid biology. This tutorial provides an overview of fatty acid biology with the goal of increasing comfort in discussing how these heterogeneous molecules are classified and metabolized, in addition to how fatty acid content influences basic cellular processes.     

Plasma fatty acid profiles in 37 pairs of maternal and umbilical cord blood samples

Objectives and Methods In order to study the fatty acid transfer from the mother to fetus, their fatty acid profiles were compared by 37 pairs of maternal and umbilical cord plasma specimens obtained from healthy Japanese women at delivery. Results The fetal/maternal fatty acid concentration ratios differed among individual fatty acids. The ratios were low for linoleic acid (LN, 0.12±0.04) and linolenic acid (LnN, 0.07±0.05) but high for arachidonic acid (AA, 0.66±0.17) and docosahexaenoic acid (DHA, 0.44±0.13). Significant correlations were observed between the maternal and fetal EPA (r=0.74) and DHA (r=0.40) concentrations. Conclusions These results suggest that DHA and AA are preferentially transferred to the fetus. Fetal fatty acid profile reflects the maternal intake of EPA and DHA.     

Safety and Efficacy of Fish Oil–Enriched Parenteral Nutrition Regimen on Postoperative Patients Undergoing Major Abdominal Surgery

Background: To evaluate the safety and efficacy of a fish oil–enriched parenteral nutrition regimen in patients undergoing major abdominal surgery, a meta‐analysis of randomized controlled trials was conducted. Methods: An electronic search of PubMed, MEDLINE, EMBASE, Academic Search Premier, and China National Knowledge Infrastructure databases was performed in March 2009. RevMan 5.0 was used for statistical analysis. Results: The combined analysis showed that a fish oil–enriched parenteral nutrition regimen had a positive treatment effect on length of hospital stay (weighed mean difference = ?2.98, P < .001), length of intensive care unit stay, postoperative infection rate (odds ratio = 0.56, P = .04), and serum levels of aspartate aminotransferase, alanine aminotransferase, and α‐tocopherol on postoperative day 6 in these patients. The regimen increased the plasma levels of eicosapentaenoic acid (standardized mean difference = 3.11, P < .001) and docosahexaenoic acid and upregulated the leukotriene B₅ production in leukocytes on postoperative day 6. No significant differences were found between the 2 groups in postoperative mortality; incidence of postoperative cardiac complications; serum levels of bilirubin, triglyceride, or arachidonic acid; or the liberation of leukotriene B₄. No serious adverse events related to fish oil treatment were reported. Conclusions: Based on the meta‐analysis, fish oil–supplemented parenteral nutrition was safe, improved clinical outcomes, and altered the fatty acid pattern as well as leukotriene synthesis. More laboratory parameters should be considered in future meta‐analyses.     

Total dietary fat and fatty acid content modifies plasma phospholipid fatty acids,desaturase activity indices,and urinary prostaglandin E in women

Compared with diets high in fat, low-fat diets are associated with reduced risk of cardiovascular disease. We hypothesized that a low-fat (LF) (20% fat) and an LF high–omega-3 (n-3) fatty acid diet (LFn3) (23% fat with 3% as α-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid [DHA]) would enhance n-3 composition of plasma phospholipid fatty acid and reduce urinary prostaglandin E₂ (PGE₂) relative to a high-fat diet (HF) (40% fat) and that these changes would be associated with alterations in δ5 desaturase (D5D) and δ6 desaturase (D6D) activity. Phospholipid fatty acids and urinary PGE₂ were measured, and D5D and D6D activity indices calculated in a crossover trial in 17 postmenopausal women fed each of 3 test diets (HF, LF, and LFn3) for 8-week feeding periods. Desaturase activity indices were calculated as D5D, 20:4n-6/20:3n-6, and D6D, 20:3n-6/18:2n-6. Plasma phospholipid fatty acid, α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid (DPA), DHA, and total n-3 fatty acids increased, whereas linoleic acid and arachidonic acid decreased with consumption of LFn3. The LF resulted in enhanced arachidonic acid and DHA. High fat reduced D6D, whereas both HF and LF increased D5D. Urinary PGE₂ was reduced in response to both the LF and LFn3 diets. Low-fat diets, with or without long-chain n-3 fatty acids, promote positive health effects due in part to favorable alteration of plasma phospholipid fatty acid profiles and modification in desaturase activity indices, suggesting that the type and amount of fat consumed are modifiable risk factors for the prevention of cardiovascular disease.     

Bioavailability of long-chain omega-3 polyunsaturated fatty acid enriched luncheon meats

(Nutr Diet 2005;62:130–137) Objective: To determine the acute and chronic effects of low doses of long chain (LC) n‐3 polyunsaturated fatty acids (PUFA) on plasma LC n‐3 PUFA levels. Design: In the acute study, six healthy omnivores, avoiding fish meals on the day prior to the study, provided a fasting blood sample initially and post prandially at four hours. In the chronic study, 12 healthy subjects provided a fasting blood sample at baseline and three weeks after daily consumption of the test food. Main outcome measures: Plasma non‐esterified fatty acid and phospholipid LC n‐3 PUFA composition. Statistical analysis: Differences in plasma non‐esterified fatty acids and phospholipid LC n‐3 PUFA. A pre‐ and post‐consumption of the test food were assessed using paired t‐tests (spss ). Results: The acute study demonstrated that a low dose of LC n‐3 PUFA (25% eicosapentaenoic acid and 75% docosahexaenoic acid) significantly increased eicosapentaenoic acid levels in plasma of human subjects postprandially from 0.30% to 0.42% of total non‐esterified fatty acids, a per cent change of 39% (P < 0.05). The chronic study demonstrated a significant increase in total n‐3 phospholipids from zero weeks (5.48% of total fatty acids) to three weeks (7.92% of total fatty acids), representing a per cent increase of 44% (P = 0.006). The n‐6 to n‐3 ratio of LC PUFA phospholipids demonstrated a significant reduction from 5.1 at zero weeks to 4.07 at three weeks, representing a reduction of 20% (P = 0.006). Conclusions: These findings demonstrate the bioavailability of LC n‐3 PUFA consumed as a low‐fat omega‐3‐enriched luncheon meat.     

Rapid Incorporation of ω‐3 Fatty Acids Into Colonic Tissue After Oral Supplementation in Patients With Colorectal Cancer

Background: The purpose of the study was to examine whether a preoperative supplement with ω‐3 fatty acids (FAs) leads to their incorporation into colonic tissue in patients scheduled for colorectal cancer surgery. This would be of interest because ω‐3 FAs have potential beneficial (local) immunological effects that might benefit these patients. Methods: In a randomized, double‐blind, prospective, placebo‐controlled, single‐center intervention trial, patients referred for elective colorectal cancer surgery received either an ω‐3 FA–enriched oral nutrition supplement (ONS) (200 mL twice daily) providing 2.0 g of eicosapentaenoic acid (EPA) and 1.0 g of docosahexaenoic acid (DHA) per day or a standard ONS for 7 days before surgery. Tissue samples from healthy colonic tissue (mucosa and muscular layer) were obtained during surgery, and tissue fatty acid composition was analyzed by gas chromatography. Results: EPA was significantly higher in colonic mucosa (P = .001) and in the colonic muscular layer (P = .004) in the ω‐3 FA group compared with controls. Patients in the ω‐3 FA group also tended to have higher docosapentaenoic acid and DHA levels in colonic tissue. Conclusions: EPA is incorporated rapidly into colonic mucosa and colonic muscular layer in patients given 3 g of ω‐3 FA daily for 7 days before surgery for colorectal cancer. This may lead to potential beneficially effects on (local) immune function, which might benefit these patients.     

Clinical aspects of essential fatty acid metabolism: Jonathan Rhoads Lecture

The clinical implications of the metabolism of the 2 essential fatty acids, linoleic and alpha-linolenic acid, are most clearly related to the membrane phospholipid concentrations of their elongation and desaturation products, arachidonic, eicosapentaenoic, and docosahexaenoic acid. Levels of these very long chain polyunsaturated fatty acids can be altered by diet, prematurity, and disease which can affect growth (nutritional repletion) and the intensity and character of systemic inflammation as well as cognitive and visual function in infants.     

Fatty acid profiles,antioxidant status,and growth of preterm infants fed diets without or with long-chain polyunsaturated fatty acids

Summary. Long-chain polyunsaturated fatty acids (LCP) are considered conditionally essential nutrients for the infant born prematurely, and attempts are being made to match fatty acid profiles of formula and breast fed infants. In this double-blind, randomized study we investigated the effects of a formula enriched with both n-6 and n-3 LCP on plasma fatty acid profiles, antioxidant status and growth of premature infants. 29 infants received either a formula devoid of LCP or a LCP supplemented formula (0.5 g/100 g fat linoleic acid metabolites, 0.8 g/100 g fat -linolenic acid metabolites). 17 breast fed infants served as a control group. At study entry as well as two and four weeks later, plasma and urine samples were collected, growth data obtained and food tolerance was documented. At the end of the four week study period, plasma docosahexaenoic acid (DHA) levels of supplemented infants were significantly higher than those of unsupplemented infants and similar to those of infants fed human milk. Plasma n-6 LCP concentrations including arachidonic acid (AA) were similar between groups. The plasma -tocopherol levels of breast fed and supplemented infants were similar and tended to be lower than in infants fed the formula devoid of LCP. Urinary malondialdehyde (MDA) excretion of formula fed infants was significantly higher compared to infants fed human milk, but did not differ between the two formula groups. Parameters of growth and milk tolerance did not differ between groups. Our results demonstrate that plasma LCP levels similar to those of breast fed infants can be achieved with the LCP supplemented formula used in this trial, without evidence of adverse effects of the LCP enrichment.AA arachidonic acid - ALA -linolenic acid - DGLA dihomo--linolenic acid - DHA docosahexaenoic acid - EPA eicosapentaenoic acid - F formula devoid of LCP - GLA -linolenic acid - HM human milk - LA linoleic acid - LCP long-chain polyunsaturated fatty acids - LCP-F formula enriched with LCP - MDA malondialdehyde - PC phosphatidylcholine - PCA postconceptional age - PE phosphatidylethanolamine - PUFA polyunsaturated fatty acid     

ω‐3 Fatty Acids Prevent Hepatic Steatosis,Independent of PPAR‐α Activity,in a Murine Model of Parenteral Nutrition–Associated Liver Disease

Objectives: ω‐3 Fatty acids (FAs), natural ligands for the peroxisome proliferator‐activated receptor–α (PPAR‐α), attenuate parenteral nutrition–associated liver disease (PNALD). However, the mechanisms underlying the protective role of ω‐3 FAs are still unknown. The aim of this study was to determine the effects of ω‐3 FAs on hepatic triglyceride (TG) accumulation in a murine model of PNALD and to investigate the role of PPAR‐α and microsomal triglyceride transfer protein (MTP) in this experimental setting. Methods: 129S1/SvImJ wild‐type or 129S4/SvJaePparatm/Gonz/J PPAR‐α knockout mice were fed chow and water (controls); oral, fat‐free PN solution only (PN‐O); PN‐O plus intraperitoneal (IP) ω‐6 FA‐predominant supplements (PN–ω‐6); or PN‐O plus IP ω‐3 FA (PN–ω‐3). Control and PN‐O groups received sham IP injections of 0.9% NaCl. Hepatic histology, TG and cholesterol, MTP activity, and PPAR‐α messenger RNA were assessed after 19 days. Results: In all experimental groups, PN feeding increased hepatic TG and MTP activity compared with controls. Both PN‐O and PN–ω‐6 groups accumulated significantly greater amounts of TG when compared with PN–ω‐3 mice. Studies in PPAR‐α null animals showed that PN feeding increases hepatic TG as in wild‐type mice. PPAR‐α null mice in the PN‐O and PN–ω‐6 groups demonstrated variable degrees of hepatic steatosis, whereas no evidence of hepatic fat accumulation was found after 19 days of oral PN plus IP ω‐3 FAs. Conclusions: PN induces TG accumulation (steatosis) in wild‐type and PPAR‐α null mice. In PN‐fed wild‐type and PPAR‐α null mice given IP ω‐3 FAs, reduced hepatic TG accumulation and absent steatosis are found. Prevention of steatosis by ω‐3 FAs results from PPAR‐α–independent pathways.     

Fatty acid composition of frequently consumed foods in Turkey with special emphasis on trans fatty acids

Fatty acid compositions of frequently consumed foods in Turkey were analyzed by capillary gas chromatography with particular emphasis on trans fatty acids. The survey was carried out on 134 samples that were categorized as meat products, chocolates, bakery products and others. The meat products except chicken-based foods have trans fatty acids, arising as a result of ruminant activity, with an average content of 1.45 g/100 g fatty acids. The conjugated linoleic acid content of meat and chicken doner kebabs were found higher than other meat products. Chocolate samples contained trans fatty acids less than 0.17 g/100 g fatty acids, with the exceptional national product of chocolate bars and hazelnut cocoa cream (2.03 and 3.68 g/100 g fatty acids, respectively). Bakery products have the highest trans fatty acid contents and ranged from 0.99 to 17.77 g/100 g fatty acids. The average trans fatty acid contents of infant formula and ice-cream, which are milk-based products, were 0.79 and 1.50 g/100 g fatty acids, respectively. Among the analyzed foods, it was found that coffee whitener and powdered whipped topping had the highest saturated fatty acid contents, with an average content of 98.71 g/100 g fatty acids.     

Dietary conjugated linoleic acid isomers change the unsaturation degree of hepatic fatty acids in neutral lipids but not in polar lipids

The fatty acid composition of phospholipids plays a key role in the structural and functional properties of cellular membrane. In this study, it was hypothesized that conjugated linoleic acid (CLA) isomer supplementation changes the unsaturation degree of the fatty acids of neutral lipids (NLs) but not those of polar lipids (PLs). Thus, the main goal was to determine the pattern of fatty acid incorporation into hepatic PL and NL fractions. Wistar male rats were fed cis(c)9,trans(t)11 and t10,c12 CLA isomers, separately or as a mixture. Whereas the t10,c12 isomer incorporation in the PL fraction was similar when supplemented either individually or as a mixture, the c9,t11 isomer reached the highest values of incorporation when combined with t10,c12. In the PL fraction, the linoleic acid did not change; but the arachidonic acid decreased, especially in the rats given the mixture. Also in this fraction, the t10,c12 isomer, either separately or as a mixture, decreased the amounts of n-6 long-chain (LC) polyunsaturated fatty acids (PUFA) and increased those of the n-3 LC PUFA relative to the control. In the NL fraction, linoleic acid incorporation followed the diet composition, whereas the arachidonic acid was similar among treatments. Facing CLA isomer supplementation, the present study suggests that fatty acid incorporation into phospholipids, through the balance between n-6 and n-3 LC PUFA, is dependent upon maintaining the unsaturation degree of cellular membrane.     

Fatty acid composition of colostrum and mature human milk in Hungary

INTRODUCTION AND AIMS: Because of the lack of up-to-date data on fatty acid composition of human milk in Hungary, the authors analysed fatty acid composition of colostrum (n = 18, one hind milk sample on day 5 after delivery) and mature milk (n = 15, pooled 24 h collections repeated twice with 2 weeks intervals at median duration of lactation of 4 months) samples with high-resolution capillary gas chromatography. RESULTS: Fat content and fatty acid compositions did not differ in 24 h pooled mature human milk samples obtained with 2 weeks intervals. Significantly lower values of linoleic acid [10.98 (4.81) vs. 14.70 (5.32), % w/w, median (range from the 1st to the 3rd quartile), colostrum vs. mature human milk, p < 0.001] and alpha-linolenic acid [0.22 (0.09) vs. 0.68 (0.21), p < 0.0001], and significantly higher values of arachidonic acid [0.70 (0.56) vs. 0.50 (0.12), p < 0.001] and docosahexaenoic acid [0.22 (0.15) vs. 0.18 (0.06), p < 0.05] were found in colostrum than in mature human milk. Significant and positive correlations were seen between linoleic and arachidonic (r = 0.71, p = 0.001) as well as between alpha-linolenic and docosahexaenoic (r = 0.59, p = 0.01) acid values in colostrum, but not in mature human milk. CONCLUSION: While mature human milk linoleic, arachidonic and alpha-linolenic acid values in this study were in the range usually reported in the literature, the contribution of docosahexaenoic acid to the fatty acid composition of human milk was considerably lower in Hungary than in several other populations.