the-use-gas-chromatography-to-analyze-compositional-changes-fatty

The Use of Gas Chromatography to Analyze Compositional Changes of Fatty Acids in Rat Liver Tissue during Pregnancy

Gas chromatography (GC) is a highly sensitive method used to identify and quantify the fatty acid content of lipids from tissues, cells, and plasma/serum, ...

University of Southampton

The fatty acid composition of cell membranes can be modified in cell culture. The role of different fatty acid families in modulating phagocytosis and oxidative burst is not clear and therefore the influence of 18-carbon polyunsaturated fatty acids (PUFA) on these processes was examined. The mouse monocyte/macrophage line P388D1 was cultured in medium supplemented with 2 or 20 micromol/l 18:2n-6 (linoleic acid; LA) or 18:3n-3 (alpha-linolenic acid; LNA) and fatty acid enrichment of the cells was tested after 8 days. The macrophages were activated with phorbol ester in order to promote oxidative burst and intracellular dihydrorhodamine oxidation was determined. To test phagocytosis capacity uptake of fluorescence-labeled Escherichia coli was determined. Activation of the transcription factor nuclear factor (NF)-kappaB was also determined. Cells grown in medium with 20 micromol/l LA contained 2- to 3-fold more n-6 PUFA including 4-fold more arachidonic acid. Cells grown in medium with 20 micromol/l LNA contained 4-fold more n-3 PUFA. Both LA and LNA enhanced phagocytosis and decreased oxidative burst, with little difference between the fatty acids. NF-kappaB activation at 1 h post-stimulation was not affected by adding LA or LNA to the culture medium. We conclude that the fatty acid composition of macrophages influences their ability to phagocytose and mount oxidative burst.

Membrane fatty acids, oxidative burst and phagocytosis after enrichment of P388D1 monocyte/macrophages with essential 18-carbon fatty acids.

The lipid-modulatory effects of high intakes of the fish-oil fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are well established and likely to contribute to cardioprotective benefits.

Effect of sex and genotype on cardiovascular biomarker response to fish oils: the FINGEN Study.

To determine whether very long-chain n-3 polyunsaturated fatty acids (PUFAs) affect illness and selected plasma cytokines in schoolchildren.

Fish oil n-3 polyunsaturated fatty acids selectively affect plasma cytokines and decrease illness in Thai schoolchildren: a randomized, double-blind, placebo-controlled intervention trial.

Omega-3 polyunsaturated fatty acids (n-3 PUFA) have been reported to reduce the risk of sudden cardiac death presumed to be due to fatal ventricular arrhythmias, but their effect on atrial arrhythmias is unclear.

Omega-3 fatty acid supplementation does not reduce risk of atrial fibrillation after coronary artery bypass surgery: a randomized, double-blind, placebo-controlled clinical trial.

Estimation of the intake of oily fish at a population level is difficult. The measurement of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in biological samples may provide a useful biomarker of intake.

Incorporation of eicosapentaenoic and docosahexaenoic acids into lipid pools when given as supplements providing doses equivalent to typical intakes of oily fish.

The importance of route of administration of omega-3 (n-3) polyunsaturated fatty acids (PUFA) (oral vs intravenous (iv)) is not clear. We determined the relative concentrations of fatty acids in plasma phosphatidylcholine (PC), red blood cells (RBC), white blood cells (WBC) and several tissues after short-term oral or iv administration of soybean oil (SO) or fish oil (FO).

Fatty acids in plasma, white and red blood cells, and tissues after oral or intravenous administration of fish oil in rats.

Limited work is available on the benefits of nutritional support enriched with arginine and n-3 fatty acids in surgical patients with head and neck cancer, particularly if well-nourished. We conducted a pilot study in these patients to examine effects on inflammatory markers and clinical outcome. Patients scheduled for radical resection of the oral cavity were randomised to 5 day preoperative and 5 day postoperative Impact® (IMN, n = 4), or no preoperative supplementary nutrition and Isosource® postoperatively (STD, n = 4). Plasma fatty acids, C-reactive protein (CRP), tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10 were measured at baseline, day of surgery and on postoperative days (POD) 2, 4 and 10. Postoperative complications were recorded. The (eicosapentaenoic acid plus docosahexaenoic acid) to arachidonic acid ratio was significantly higher in IMN patients on POD 2, 4 and 10 (P < 0.01). While not statistically significant, CRP, TNF-α, and IL-6 concentrations were higher in the STD group on POD2 while IL-10 was lower. Median length of stay was 10 (range 10-43) days in the IMN group and 21.5 (7-24) days in the STD group. Five complications were seen in the STD group and two in the IMN group. The results support the need for a larger trial focusing on clinical outcome.

Perioperative immunonutrition in well-nourished patients undergoing surgery for head and neck cancer: evaluation of inflammatory and immunologic outcomes.

Mediators derived from the n-6 polyunsaturated fatty acid (PUFA) arachidonic acid oxidation have been shown to have tumour promoting effects in experimental models, while n-3 PUFAs are thought to be protective. Here we report fatty acid concentrations in hepatic colorectal metastases compared to liver tissue without tumour in humans.

Unsaturated fatty acids differ between hepatic colorectal metastases and liver tissue without tumour in humans: results from a randomised controlled trial of intravenous eicosapentaenoic and docosahexaenoic acids.

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are functionally the most important omega-3 polyunsaturated fatty acids (PUFAs). Oral supply of these fatty acids increases their levels in plasma and cell membranes, often at the expense of the omega-6 PUFAs arachidonic acid (ARA) and linoleic acid. This results in an altered pattern of lipid mediator production to one which is less pro-inflammatory. We investigated whether short term intravenous supply of omega-3 PUFAs could change the levels of EPA, DHA, ARA and linoleic acid in plasma and erythrocytes in patients with hepatic colorectal metastases.

Changes in plasma and erythrocyte omega-6 and omega-3 fatty acids in response to intravenous supply of omega-3 fatty acids in patients with hepatic colorectal metastases.

The long-chain n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have human health benefits. Alternatives to fish as sources of EPA and DHA are needed. Oil from the micro-algae Nannochloropsis oculata contains a significant amount of EPA conjugated to phospholipids and glycolipids and no DHA. Krill oil contains EPA and DHA conjugated to phospholipids. We compare the appearance of fatty acids in blood plasma of healthy humans after consuming a high fat meal followed by either algal oil or krill oil.

Acute appearance of fatty acids in human plasma--a comparative study between polar-lipid rich oil from the microalgae Nannochloropsis oculata and krill oil in healthy young males.

The aim of the present study was to determine whether age and sex influence both the status and incorporation of EPA and DHA into blood plasma, cells and tissues. The study was a double-blind, randomised, controlled intervention trial, providing EPA plus DHA equivalent to 0, 1, 2 or 4 portions of oily fish per week for 12 months. The participants were stratified by age and sex. A linear regression model was used to analyse baseline outcomes, with covariates for age or sex groups and by adjusting for BMI. The change in outcomes from baseline to 12 months was analysed with additional adjustment for treatment and average compliance. Fatty acid profiles in plasma phosphatidylcholine, cholesteryl esters, NEFA and TAG, mononuclear cells (MNC), erythrocyte membranes, platelets, buccal cells (BU) and adipose tissue (AT) were determined. At baseline, EPA concentrations in plasma NEFA and DHA concentrations in MNC, BU and AT were higher in females than in males (all P< 0·05). The concentrations of EPA in AT (P= 0·003) and those of DHA in plasma TAG (P< 0·01) and AT (P< 0·001) were higher with increasing age. Following 12-month supplementation with EPA plus DHA, adjusted mean difference for change in EPA concentrations in plasma TAG was significantly higher in females than in males (P< 0·05) and was greater with increasing age (P= 0·02). Adjusted mean difference for change in DHA concentrations in AT was significantly smaller with increasing age (P= 0·02). Although small differences in incorporation with age and sex were identified, these were not of sufficient magnitude to warrant a move away from population-level diet recommendations for n-3 PUFA.

Article	Year
Membrane fatty acids, oxidative burst and phagocytosis after enrichment of P388D1 monocyte/macrophages with essential 18-carbon fatty acids. Annals of nutrition & metabolism\| PubMed ID: 17536193	2007
Effect of sex and genotype on cardiovascular biomarker response to fish oils: the FINGEN Study. The American journal of clinical nutrition\| PubMed ID: 18779276	2008
Fish oil n-3 polyunsaturated fatty acids selectively affect plasma cytokines and decrease illness in Thai schoolchildren: a randomized, double-blind, placebo-controlled intervention trial. The Journal of pediatrics\| PubMed ID: 18930251	2009
Omega-3 fatty acid supplementation does not reduce risk of atrial fibrillation after coronary artery bypass surgery: a randomized, double-blind, placebo-controlled clinical trial. Circulation. Arrhythmia and electrophysiology\| PubMed ID: 20042769	2010
Incorporation of eicosapentaenoic and docosahexaenoic acids into lipid pools when given as supplements providing doses equivalent to typical intakes of oily fish. The American journal of clinical nutrition\| PubMed ID: 22932281	2012
Fatty acids in plasma, white and red blood cells, and tissues after oral or intravenous administration of fish oil in rats. Clinical nutrition (Edinburgh, Scotland)\| PubMed ID: 23541913	2013
Perioperative immunonutrition in well-nourished patients undergoing surgery for head and neck cancer: evaluation of inflammatory and immunologic outcomes. Nutrients\| PubMed ID: 23571650	2013
Unsaturated fatty acids differ between hepatic colorectal metastases and liver tissue without tumour in humans: results from a randomised controlled trial of intravenous eicosapentaenoic and... Prostaglandins, leukotrienes, and essential fatty acids\| PubMed ID: 23647811	2013
Changes in plasma and erythrocyte omega-6 and omega-3 fatty acids in response to intravenous supply of omega-3 fatty acids in patients with hepatic colorectal metastases. Lipids in health and disease\| PubMed ID: 23648075	2013
Acute appearance of fatty acids in human plasma--a comparative study between polar-lipid rich oil from the microalgae Nannochloropsis oculata and krill oil in healthy young males. Lipids in health and disease\| PubMed ID: 23855409	2013
Age and sex differences in the incorporation of EPA and DHA into plasma fractions, cells and adipose tissue in humans. The British journal of nutrition\| PubMed ID: 24063767	2014

Annette L. West

Biography

JoVE Journal Publications

Other Publications