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Biochimica Et Biophysica Acta Dec 2009Arachidonic acid (AA) and its oxygenated derivatives, collectively known as the eicosanoids, are key mediators of a wide variety of physiological and pathophysiological... (Review)
Review
Arachidonic acid (AA) and its oxygenated derivatives, collectively known as the eicosanoids, are key mediators of a wide variety of physiological and pathophysiological states. AA, obtained from the diet or synthesized from linoleic acid, is rapidly incorporated into cellular phospholipids by the concerted action of arachidonoyl-CoA synthetase and lysophospholipid acyltransferases. Under the appropriate conditions, AA is liberated from its phospholipid storage sites by the action of one or various phospholipase A(2) enzymes. Thus, cellular availability of AA, and hence the amount of eicosanoids produced, depends on an exquisite balance between phospholipid reacylation and hydrolysis reactions. This review focuses on the enzyme families that are involved in these reactions in resting and stimulated cells.
Topics: 1-Acylglycerophosphocholine O-Acyltransferase; Animals; Arachidonic Acid; Biological Transport; Humans; Phospholipases A2; Phospholipids
PubMed: 19715771
DOI: 10.1016/j.bbalip.2009.08.007 -
Neuromolecular Medicine Mar 2021The abundance of docosahexaenoic acid (DHA) in phospholipids in the brain and retina has generated interest to search for its role in mediating neurological functions.... (Comparative Study)
Comparative Study
The abundance of docosahexaenoic acid (DHA) in phospholipids in the brain and retina has generated interest to search for its role in mediating neurological functions. Besides the source of many oxylipins with pro-resolving properties, DHA also undergoes peroxidation, producing 4-hydroxyhexenal (4-HHE), although its function remains elusive. Despite wide dietary consumption, whether supplementation of DHA may alter the peroxidation products and their relationship to phospholipid species in brain and other body organs have not been explored sufficiently. In this study, adult mice were administered a control or DHA-enriched diet for 3 weeks, and phospholipid species and peroxidation products were examined in brain, heart, and plasma. Results demonstrated that this dietary regimen increased (n-3) and decreased (n-6) species to different extent in all major phospholipid classes (PC, dPE, PE-pl, PI and PS) examined. Besides changes in phospholipid species, DHA-enriched diet also showed substantial increases in 4-HHE in brain, heart, and plasma. Among different brain regions, the hippocampus responded to the DHA-enriched diet showing significant increase in 4-HHE. Considering the pro- and anti-inflammatory pathways mediated by the (n-6) and (n-3) polyunsaturated fatty acids, unveiling the ability for DHA-enriched diet to alter phospholipid species and lipid peroxidation products in the brain and in different body organs may be an important step forward towards understanding the mechanism(s) for this (n-3) fatty acid on health and diseases.
Topics: Aldehydes; Animals; Brain; Chromatography, Liquid; Dietary Supplements; Docosahexaenoic Acids; Heart; Lipid Peroxidation; Male; Mice; Mice, Inbred C57BL; Myocardium; Organ Specificity; Oxidation-Reduction; Phospholipids; Plasma; Random Allocation; Tandem Mass Spectrometry
PubMed: 32926329
DOI: 10.1007/s12017-020-08616-0 -
European Journal of Nutrition Oct 2022UK guidelines recommend dietary saturated fatty acids (SFAs) should not exceed 10% total energy (%TE) for cardiovascular disease prevention, with benefits observed when...
Impact of a food-based dietary fat exchange model for replacing dietary saturated with unsaturated fatty acids in healthy men on plasma phospholipids fatty acid profiles and dietary patterns.
PURPOSE
UK guidelines recommend dietary saturated fatty acids (SFAs) should not exceed 10% total energy (%TE) for cardiovascular disease prevention, with benefits observed when SFAs are replaced with unsaturated fatty acids (UFAs). This study aimed to assess the efficacy of a dietary exchange model using commercially available foods to replace SFAs with UFAs.
METHODS
Healthy men (n = 109, age 48, SD 11 year) recruited to the Reading, Imperial, Surrey, Saturated fat Cholesterol Intervention-1 (RISSCI-1) study (ClinicalTrials.Gov n°NCT03270527) followed two sequential 4-week isoenergetic moderate-fat (34%TE) diets: high-SFA (18%TE SFAs, 16%TE UFAs) and low-SFA (10%TE SFAs, 24%TE UFAs). Dietary intakes were assessed using 4-day weighed diet diaries. Nutrient intakes were analysed using paired t-tests, fasting plasma phospholipid fatty acid (PL-FA) profiles and dietary patterns were analysed using orthogonal partial least square discriminant analyses.
RESULTS
Participants exchanged 10.2%TE (SD 4.1) SFAs for 9.7%TE (SD 3.9) UFAs between the high and low-SFA diets, reaching target intakes with minimal effect on other nutrients or energy intakes. Analyses of dietary patterns confirmed successful incorporation of recommended foods from commercially available sources (e.g. dairy products, snacks, oils, and fats), without affecting participants' overall dietary intakes. Analyses of plasma PL-FAs indicated good compliance to the dietary intervention and foods of varying SFA content.
CONCLUSIONS
RISSCI-1 dietary exchange model successfully replaced dietary SFAs with UFAs in free-living healthy men using commercially available foods, and without altering their dietary patterns. Further intervention studies are required to confirm utility and feasibility of such food-based dietary fat replacement models at a population level.
Topics: Adult; Cardiovascular Diseases; Diet; Dietary Fats; Fatty Acids; Fatty Acids, Unsaturated; Humans; Male; Middle Aged; Phospholipids
PubMed: 35668120
DOI: 10.1007/s00394-022-02910-2 -
Hepatology (Baltimore, Md.) Apr 2017Nonalcoholic fatty liver disease (NAFLD) can progress from simple steatosis (i.e., nonalcoholic fatty liver [NAFL]) to nonalcoholic steatohepatitis (NASH), cirrhosis,... (Comparative Study)
Comparative Study
UNLABELLED
Nonalcoholic fatty liver disease (NAFLD) can progress from simple steatosis (i.e., nonalcoholic fatty liver [NAFL]) to nonalcoholic steatohepatitis (NASH), cirrhosis, and cancer. Currently, the driver for this progression is not fully understood; in particular, it is not known how NAFLD and its early progression affects the distribution of lipids in the liver, producing lipotoxicity and inflammation. In this study, we used dietary and genetic mouse models of NAFL and NASH and translated the results to humans by correlating the spatial distribution of lipids in liver tissue with disease progression using advanced mass spectrometry imaging technology. We identified several lipids with distinct zonal distributions in control and NAFL samples and observed partial to complete loss of lipid zonation in NASH. In addition, we found increased hepatic expression of genes associated with remodeling the phospholipid membrane, release of arachidonic acid (AA) from the membrane, and production of eicosanoid species that promote inflammation and cell injury. The results of our immunohistochemistry analyses suggest that the zonal location of remodeling enzyme LPCAT2 plays a role in the change in spatial distribution for AA-containing lipids. This results in a cycle of AA-enrichment in pericentral hepatocytes, membrane release of AA, and generation of proinflammatory eicosanoids and may account for increased oxidative damage in pericentral regions in NASH.
CONCLUSION
NAFLD is associated not only with lipid enrichment, but also with zonal changes of specific lipids and their associated metabolic pathways. This may play a role in the heterogeneous development of NAFLD. (Hepatology 2017;65:1165-1180).
Topics: Animals; Biopsy, Needle; Diet, High-Fat; Diet, Western; Disease Models, Animal; Eicosanoids; Fatty Liver; Humans; Immunohistochemistry; Liver Cirrhosis; Liver Neoplasms; Liver Regeneration; Male; Mass Spectrometry; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Phospholipids; Prognosis; Random Allocation; Risk Assessment; Severity of Illness Index; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 27863448
DOI: 10.1002/hep.28953 -
Journal of Lipid Research Jan 1969Many complex problems of lipid metabolism are especially suited for multicompartmental analysis with computers. Examples are presented. The use of a model as a means of... (Review)
Review
Many complex problems of lipid metabolism are especially suited for multicompartmental analysis with computers. Examples are presented. The use of a model as a means of communicating one's working hypothesis and the model as it relates to experimental design are discussed. A number of principles relating to experimental design and to the interpretation and presentation of data are illustrated by 12 studies selected from the literature. These include evaluations of turnover and transport rates of liver and plasma triglycerides, triglyceride synthesis, phospholipid synthesis, and lipid oxidation to CO2. A discussion of computer-oriented vs. noncomputer-oriented techniques is included. Some of the practical problems involved in computer analysis are also considered. Among these are the choice of computer, computer applications, stepwise vs. multicompartmental analysis, validity of single-injection type experiments, avoidance of multicompartmental analysis, nonsteady state systems, and nomenclature.
Topics: Albumins; Animals; Bicarbonates; Biological Transport; Carbon Dioxide; Carbon Isotopes; Computers; Dietary Carbohydrates; Fasting; Fatty Acids; Fatty Acids, Nonesterified; Humans; Lipid Metabolism; Lipoproteins; Liver; Models, Chemical; Palmitic Acids; Phosphatidylcholines; Phospholipids; Phosphorus Isotopes; Rats; Serine; Terminology as Topic; Time Factors; Triglycerides; Tritium
PubMed: 4884733
DOI: No ID Found -
Nutrients Jan 2022The retina requires docosahexaenoic acid (DHA) for optimal function. Alpha-linolenic acid (ALA) and DHA are dietary sources of retinal DHA. This research investigated...
The retina requires docosahexaenoic acid (DHA) for optimal function. Alpha-linolenic acid (ALA) and DHA are dietary sources of retinal DHA. This research investigated optimizing retinal DHA using dietary ALA. Previous research identified 19% DHA in retinal phospholipids was associated with optimal retinal function in guinea pigs. Pregnant guinea pigs were fed dietary ALA from 2.8% to 17.3% of diet fatty acids, at a constant level of linoleic acid (LA) of 18% for the last one third of gestation and retinal DHA levels were assessed in 3-week-old offspring maintained on the same diets as their mothers. Retinal DHA increased in a linear fashion with the maximum on the diet with LA:ALA of 1:1. Feeding diets with LA:ALA of 1:1 during pregnancy and assessing retinal DHA in 3-week-old offspring was associated with optimized retinal DHA levels. We speculate that the current intakes of ALA in human diets, especially in relation to LA intakes, are inadequate to support high DHA levels in the retina.
Topics: Animal Nutritional Physiological Phenomena; Animals; Animals, Newborn; Diet; Dietary Fats; Docosahexaenoic Acids; Female; Guinea Pigs; Linoleic Acid; Maternal Nutritional Physiological Phenomena; Phospholipids; Pregnancy; Retina; alpha-Linolenic Acid
PubMed: 35057481
DOI: 10.3390/nu14020301 -
Biochimica Et Biophysica Acta Jun 2014Phosphatidylcholine is made in the liver via the CDP-choline pathway and via the conversion of phosphatidylethanolamine to phosphatidylcholine by 3 transmethylation... (Review)
Review
Phosphatidylcholine is made in the liver via the CDP-choline pathway and via the conversion of phosphatidylethanolamine to phosphatidylcholine by 3 transmethylation reactions from AdoMet catalyzed by phosphatidylethanolamine N-methyltransferase (PEMT). PEMT is a 22.3kDa integral transmembrane protein of the endoplasmic reticulum and mitochondria-associated membranes. The only tissue with quantitatively significant PEMT activity is liver; however, low levels of PEMT in adipocytes have been implicated in lipid droplet formation. PEMT activity is regulated by the concentration of substrates (phosphatidylethanolamine and AdoMet) as well as the ratio of AdoMet to AdoHcy. Transcription of PEMT is enhanced by estrogen whereas the transcription factor Sp1 is a negative regulator of PEMT transcription. Studies with mice that lack PEMT have provided novel insights into the function of this enzyme. PEMT activity is required to maintain hepatic membrane integrity and for the formation of choline when dietary choline supply is limited. PEMT is required for normal secretion of very low-density lipoproteins. The lack of PEMT protects against diet-induced atherosclerosis in two mouse models. Most unexpectedly, mice that lack PEMT are protected from diet-induced obesity and insulin resistance. Moreover, mice lacking PEMT have increased susceptibility to diet-induced fatty liver and steatohepatitis. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
Topics: Animals; Cell Physiological Phenomena; Humans; Methylation; Mice; Phosphatidylethanolamine N-Methyltransferase; Phospholipids
PubMed: 24184426
DOI: 10.1016/j.bbamem.2013.10.018 -
Poultry Science Aug 2017The aim of this study was to evaluate the effect of dietary phospholipid supplementation on laying hen performance, egg quality, and the fatty acid profile of egg yolks...
The aim of this study was to evaluate the effect of dietary phospholipid supplementation on laying hen performance, egg quality, and the fatty acid profile of egg yolks from hens fed a 2% Schizochytrium powder diet. Three-hundred-sixty 28-wk-old Hy-line W-36 laying hens were randomly allocated to one of the 5 dietary treatments, each treatment with 6 replicates of 12 birds each. All diets included 2% Schizochytrium powder (docosahexaenoic acid [DHA], 137.09 mg/g). The control group was not supplemented with any additional phospholipids, whereas the other 4 experimental diets were supplemented with 1,000 mg/kg choline (CHO), 1,000 mg/kg monoethanolamine (MEA), 1,000 mg/kg lysophosphatidylcholine (LPC), or 500 mg/kg LPC + 500 mg/kg MEA (LPC + MEA). The experimental diets were isocaloric (metabolizable energy, 11.15 MJ/kg) and isonitrogenous (crude protein, 16.60%). The feeding trial lasted 28 days. Laying hen performance and egg quality were not affected (P > 0.05) by the diets used. The monounsaturated fatty acid (MUFA) level was reduced in the LPC group at d 28 (P < 0.01), whereas the polyunsaturated fatty acid (PUFA) level was increased (P < 0.05). The omega-6 (n-6) PUFA level of the egg yolks in the LPC group had a trend to increase in comparison to the control (P = 0.07). The CHO and LPC groups had higher omega-3 (n-3) PUFA and DHA levels and lower n-6/n-3 ratios than the other groups at d 28 (P < 0.01). The DHA content in egg yolk reached a plateau after the laying hens consumed the experimental diets for 14 days, and higher yolk DHA contents were observed in the CHO and LPC groups as compared with the other groups at d 14. It was concluded that dietary choline supplementation for more than 14 d enhanced egg yolk enrichment with n-3 PUFA and DHA when laying hen diets were supplemented with 2% Schizochytrium powder. All the diets had no adverse effect on hen performance, egg quality, or egg components under the experimental condition.
Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Chickens; Choline; Diet; Dietary Fats; Dietary Supplements; Fatty Acids; Female; Ovum; Phospholipids; Random Allocation; Reproduction; Stramenopiles
PubMed: 28431151
DOI: 10.3382/ps/pex095 -
Journal of Dairy Science Jan 2023Dairy consumption is inversely related to the risk of developing type 2 diabetes in epidemiological research. One proposed hypothesis is that phospholipid (PL) species... (Review)
Review
Graduate Student Literature Review: A scoping review on the impact of consumption of dairy products on phosphatidylcholine and lysophosphatidylcholine in circulation and the liver in human studies and animal models.
Dairy consumption is inversely related to the risk of developing type 2 diabetes in epidemiological research. One proposed hypothesis is that phospholipid (PL) species associated with dairy consumption mediate this relationship. This scoping review aimed to identify the existing literature in animal and human trials investigating the impact of dairy products, including milk, yogurt, and cheese as well as dairy-derived PL supplementation on PL and its species in the circulation, summarizing the characteristics of these studies and identifying research gaps. A systematic search was conducted across 3 databases (PubMed, Scopus, and Web of Science) in March 2021. Of 2,427 identified references, 15 studies (7 humans and 8 animal studies) met the eligibility criteria and were included in the final narrative synthesis. The evidence base was heterogeneous, involving a variety of clinical and preclinical studies, metabolically healthy or obese/diabetic participants or animal models, and displayed mixed findings. Circulating postprandial concentrations of total PL were elevated acutely but unchanged after longer intervention with dairy products. The PL concentration remained stable even after a high dosage of milk supplemented with dairy-derived PL, which may be related to increased fecal excretion; however, certain phosphatidylcholine (PC) or lysophosphatidylcholine species were increased in circulation by interventions. These include several PC species with 32 to 38 total carbons in addition to the dairy biomarkers C15:0 and C17:0. The results of this scoping review demonstrate a small body of literature indicating that dairy products can influence blood concentrations of PC and lysophosphatidylcholine species in both rodents and humans without alteration of total PL and PC. There is a lack of well-designed trials in humans and animals that explore the potential differences between individual dairy foods on PL species. In addition, trials to understand the bioactive properties of PC and lysophosphatidylcholine species on cardiometabolic risk are needed.
Topics: Animals; Humans; Dairy Products; Diabetes Mellitus, Type 2; Diet; Liver; Lysophosphatidylcholines; Milk; Models, Animal; Phosphatidylcholines; Students; Yogurt
PubMed: 36400621
DOI: 10.3168/jds.2022-21938 -
International Journal of Cancer Oct 2013Animal and experimental studies have demonstrated that long-chain n-3 fatty acids inhibit the development of prostate cancer, whereas n-6 fatty acids might promote it....
Animal and experimental studies have demonstrated that long-chain n-3 fatty acids inhibit the development of prostate cancer, whereas n-6 fatty acids might promote it. We performed a case-cohort analysis within the Melbourne Collaborative Cohort Study using a random sample of 1,717 men and 464 prostate cancer cases to investigate associations between fatty acids assessed in plasma phospholipids (PPLs) or diet (estimated using a 121-item food frequency questionnaire) and prostate cancer risk. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression. Prostate cancer risk was positively associated with %PPL saturated fatty acids (SFAs); HR [95% CI] = 1.51 [1.06, 2.16] (Q5 vs. Q1, fifth vs. first quintile); p-trend = 0.003. HRs (Q5 to Q2 vs. Q1) were significantly elevated for %PPL palmitic acid. %PPL oleic acid was inversely associated with risk, HR = 0.62 [0.43, 0.91] (Q5 vs. Q1); p-trend = 0.04. No statistically significant linear trends were observed for dietary intakes. The HRs were elevated for moderate intakes of linoleic acid (Q2 and Q3 vs. Q1, 1.58 [1.10, 2.28] and 1.70 [1.18, 2.46], respectively), but the increase was not significant for higher intakes (Q4 and Q5). No association varied significantly by tumour aggressiveness (all p-homogeneity > 0.1). Prostate cancer risk was positively associated with %PPL SFA, largely attributable to palmitic acid and inversely associated with %PPL monounsaturated fatty acids, largely attributable to oleic acid. Higher risks were also observed for dietary n-6 polyunsaturated fats, primarily linoleic acid.
Topics: Adult; Aged; Aged, 80 and over; Case-Control Studies; Cohort Studies; Diet; Dietary Fats; Fatty Acids; Fatty Acids, Monounsaturated; Fatty Acids, Omega-6; Female; Humans; Linoleic Acid; Male; Middle Aged; Oleic Acid; Palmitic Acid; Phospholipids; Prospective Studies; Prostatic Neoplasms; Risk Factors; Surveys and Questionnaires
PubMed: 23575905
DOI: 10.1002/ijc.28203