Growth Inhibitory Effect of Polyunsaturated Fatty Acids (PUFAs) on Colon Cancer Cells via Their Growth Inhibitory Metabolites and Fatty Acid Composition Changes

Background

Colorectal cancer is common. Polyunsaturated fatty acids (PUFAs) exert growth-inhibitory and pro-apoptotic effects on colon cancer cells. Metabolites of PUFAs such as prostaglandins (PGs), leukotrienes (LTs) and lipoxins (LXs) play a significant role in colon cancer.

Methods

Human colon cancer LoVo and RKO cells were cultured with different concentration of PUFAs and 5-fluorouracil (5-FU) in vitro. Cell morphological changes, fatty acid composition, formation of PGE2, LTB4 and LXA4 and expression of COX-2, ALOX5, PGD synthase (PGDS), microsomal prostaglandin E synthase (mPGES) were assessed in LoVo and RKO cells when supplemented with PUFAs and 5-FU.

Results

PUFAs and 5-FU inhibited growth of LoVo and RKO cells to the same extent at the doses used and produced significant alterations in their shape. As expected, higher concentrations of supplemented PUFAs were noted in the cells compared to control. LA, GLA, AA, ALA and EPA supplementation to LoVo cells suppressed production of PGE₂, LTB₄,and ALOX5, mPGES expression, but enhanced that of LXA₄; whereas DHA enhanced PGE₂ and LXA₄ synthesis but decreased LTB₄ formation and COX-2, ALOX5, mPGES expression. In contrast, 5-FU enhanced formation of PGE₂, LTB₄ and mPGES expression, but suppressed LXA₄ synthesis and COX-2 expression. PGE₂, LTB₄ synthesis and ALOX5 expression was suppressed by LA, GLA, ALA and DHA; whereas AA, EPA and 5-FU enhanced PGE₂ but paradoxically AA decreased and EPA and 5-FU enhanced LTB4 synthesis in RKO cells. All the PUFAs tested enhanced, while 5-FU decreased LXA₄ formation in RKO cells; whereas GLA, AA, and 5-FU augmented while LA, ALA, EPA and DHA enhanced COX-2 expression in RKO cells.

Conclusions

Tumoricidal action of PUFAs on colorectal LoVo and RKO cancer cells in vitro was associated with increased formation of LXA₄, decreased synthesis of PGE₂ and LTB₄ and suppressed expression of COX-2, ALOX5, mPGES, whereas 5-FU produced contrasting actions on these indices.     

Effect of Omega-3 Fatty Acid Ethyl Esters on the Oxylipin Composition of Lipoproteins in Hypertriglyceridemic,Statin-Treated Subjects

Background

Oxylipins mediate inflammation, vascular tension, and more. Their presence in lipoproteins could explain why lipoproteins mediate nearly identical activities.

Methods

To determine how oxylipins are distributed in the lipoproteins of hypertriglyceridemic subjects, and whether omega-3 fatty acids alter them in a manner consistent with improved cardiovascular health, we recruited 15 dyslipidemic subjects whose levels of low density lipoprotein cholesterol (LDL-C) were at goal but who remained hypertriglyceridemic (200–499 mg/dL). They were treated them with the indicated dose of 4 g/d omega-3 acid ethyl esters (P-OM3) for 8 weeks. Measured oxylipins included mid-chain alcohols (HETEs, HEPEs and HDoHEs), ketones (KETEs), epoxides (as EpETrEs, EpETEs, and EpDPEs).

Results

At baseline, arachidonate-oxylipins (HETEs, KETEs, and EpETrEs) were most abundant in plasma with the greatest fraction of total abundance (mean |95% CI|) being carried in high density lipoproteins (HDL); 42% |31, 57| followed by very low density lipoproteins (VLDL); 27% |20, 36|; and LDL 21% |16, 28|. EPA- and DHA-derived oxylipins constituted less than 11% of total. HDL carried alcohols and epoxides but VLDL was also rich in ketones. Treatment decreased AA-derived oxylipins across lipoprotein classes (−23% |−33, −12|, p = 0.0003), and expanded EPA−(322% |241, 422|, p<0.0001) and DHA-derived oxylipins (123% |80, 176|, p<0.0001).

Conclusions

Each lipoprotein class carries a unique oxylipin complement. P-OM3 treatment alters the oxylipin content of all classes, reducing pro-inflammatory and increasing anti-inflammatory species, consistent with the improved inflammatory and vascular status associated with the treatment.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00959842","term_id":"NCT00959842"}}NCT00959842     

Dietary Omega-3 Fatty Acid Supplementation Reduces Inflammation in Obese Pregnant Women: A Randomized Double-Blind Controlled Clinical Trial

Objective

Long-chain omega 3 fatty acids, eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) exert potent anti-inflammatory properties in humans. This study characterized the effects of omega-3 ω-3 fatty acids supplements (ω-3 FA) on the inflammatory status in the placenta and adipose tissue of overweight/obese pregnant women.

Study Design

A randomized, double-masked controlled trial was conducted in overweight/obese pregnant women that were randomly assigned to receive DHA plus EPA (2g/day) or the equivalent of a placebo twice a day from week 10–16 to term. Inflammatory pathways were characterized in: 1) adipose tissue and placenta of treated vs. untreated women; and 2) adipose and trophoblast cells cultured with long chain FAs.

Results

The sum of plasma DHA and EPA increased by 5.8 fold and ω-3 FA/ ω-6 FA ratio was 1.5 in treated vs. untreated women (p< 0.005). Plasma CRP concentrations were reduced (p<0.001). The adipose tissue and placenta of treated women exhibited a significant decrease in TLR4 adipose and placental expression as well as IL6, IL8, and TNFα In vitro, EPA and DHA suppressed the activation of TLR4, IL6, IL8 induced by palmitate in culture of adipose and trophoblast cells.

Conclusion

Supplementation of overweight/obese pregnant women with dietary ω-3 FAs for >25 weeks reduced inflammation in maternal adipose and the placental tissue. TLR4 appears as a central target of the anti-inflammatory effects at the cellular level.

Trial Registration

ClinicalTrials.gov NCT00957476     

Inflammatory Markers and Immune Response to Pneumococcal Vaccination in HIV-Positive and -Negative Adults

Background

Members of the Tumor Necrosis Factor (TNF)-superfamily have speculated roles in the response against T-independent type II antigens (TI-II) including pneumococcal polysaccharides (PPS). Dysregulation in their expression is associated with an enhanced risk for pneumococcal disease in neonates but their expression in other high-risk populations including HIV-positive individuals remains to be elucidated.

Objective

To investigate signals that contribute towards PPS-response and identify potential anomalies that may account for diminished serological response in HIV-positive individuals post Pneumovax (PPV23) immunization.

Methods

Markers of inflammation, C-reactive protein (CRP), IL-6, sCD27 and sCD30, were assessed in HIV-positive and -negative individuals as potential predictors of PPV23 response. Serum levels of B cell activating factor (BAFF), transmembrane activator and calcium-modulator and cytophilin ligand interactor (TACI), B cell maturation antigen (BCMA) and B cell expression of BAFF-R, TACI, BCMA, CD40 and CD21 were assessed in total (unselected) and PPS23F (antigen)-specific B cells of PPV23 immunized HIV-positive and -negative individuals.

Results

CRP, sCD27, sCD30 and BAFF were significantly elevated in the serum of HIV-positive individuals but did not adversely affect PPV23 response. Assessment of PPS-specific B cells revealed enhanced TACI and reduced BAFF-R expression compared to unselected B cells in HIV-positive and -negative individuals. Surface TACI was similar but soluble TACI was significantly lower in HIV-positive compared to HIV-negative individuals.

Conclusion

Current studies highlight a potential role for TACI in PPV23 response based on its enhanced expression on PPS-specific B cells. Although surface levels of TACI were similar, diminished soluble TACI (sTACI) in HIV-positive compared to HIV-negative individuals could potentially decrease BAFF responsiveness and Ig response. A better understanding of the role of TNF receptors could contribute to the design of improved pneumococcal vaccines.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT02515240","term_id":"NCT02515240"}}NCT02515240     

Effects of Omega-3 Fatty Acid Supplementation on Glucose Control and Lipid Levels in Type 2 Diabetes: A Meta-Analysis

Background

Many studies assessed the impact of marine omega-3 fatty acids on glycemic homeostasis and lipid profiles in patients with type 2 diabetes (T2DM), but reported controversial results. Our goal was to systematically evaluate the effects of omega-3 on glucose control and lipid levels.

Methods

Medline, Pubmed, Cochrane Library, Embase, the National Research Register, and SIGLE were searched to identify eligible randomized clinical trials (RCTs). Extracted data from RCTs were analyzed using STATA 11.0 statistical software with fixed or random effects model. Effect sizes were presented as weighted mean differences (WMD) with 95% confidence intervals (95% CI). Heterogeneity was assessed using the Chi-square test with significance level set at p < 0.1.

Results

20 RCT trials were included into this meta-analysis. Among patients with omega-3 supplementation, triglyceride (TG) levels were significantly decreased by 0.24 mmol/L. No marked change in total cholesterol (TC), HbA1c, fasting plasma glucose, postprandial plasma glucose, BMI or body weight was observed. High ratio of EPA/DHA contributed to a greater decreasing tendency in plasma insulin, HbAc1, TC, TG, and BMI measures, although no statistical significance was identified (except TG). FPG levels were increased by 0.42 mmol/L in Asians. No evidence of publication bias was observed in this meta-analysis.

Conclusions

The ratio of EPA/DHA and early intervention with omega 3 fatty acids may affect their effects on glucose control and lipid levels, which may serve as a dietary reference for clinicians or nutritionists who manage diabetic patients.     

Niacin Skin Sensitivity Is Increased in Adolescents at Ultra-High Risk for Psychosis

Background

Most studies provide evidence that the skin flush response to nicotinic acid (niacin) stimulation is impaired in schizophrenia. However, only little is known about niacin sensitivity in the ultra-high risk (UHR) phase of psychotic disorders.

Methods

We compared visual ratings of niacin sensitivity between adolescents at UHR for psychosis according to the one year transition outcome (UHR-T n = 11; UHR-NT n = 55) with healthy controls (HC n = 25) and first episode schizophrenia patients (FEP n = 25) treated with atypical antipsychotics.

Results

Contrary to our hypothesis niacin sensitivity of the entire UHR group was not attenuated, but significantly increased compared to the HC group, whereas no difference could be found between the UHR-T and UHR-NT groups. As expected, niacin sensitivity of FEP was attenuated compared to HC group. In UHR individuals niacin sensitivity was inversely correlated with omega-6 and -9 fatty acids (FA), but positively correlated with phospholipase A₂ (inPLA₂) activity, a marker of membrane lipid repair/remodelling.

Conclusions

Increased niacin sensitivity in UHR states likely indicates an impaired balance of eicosanoids and omega-6/-9 FA at a membrane level. Our findings suggest that the emergence of psychosis is associated with an increased mobilisation of eicosanoids prior to the transition to psychosis possibly reflecting a “pro-inflammatory state”, whereas thereafter eicosanoid mobilisation seems to be attenuated. Potential treatment implications for the UHR state should be further investigated.     

Generation and Dietary Modulation of Anti-Inflammatory Electrophilic Omega-3 Fatty Acid Derivatives

Dietary ω-3 polyunsaturated fatty acids (PUFAs) decrease cardiovascular risk via suppression of inflammation. The generation of electrophilic α,β-unsaturated ketone derivatives of the ω-3 PUFAs docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA) in activated human macrophages is catalyzed by cyclooxygenase-2 (Cox-2). These derivatives are potent pleiotropic anti-inflammatory signaling mediators that act via mechanisms including the activation of Nrf2-dependent phase 2 gene expression and suppression of pro-inflammatory NF-κB-driven gene expression. Herein, the endogenous generation of ω-3 PUFAs electrophilic ketone derivatives and their hydroxy precursors was evaluated in human neutrophils. In addition, their dietary modulation was assessed through a randomized clinical trial.

Methods

Endogenous generation of electrophilic omega-3 PUFAs and their hydroxy precursors was evaluated by mass spectrometry in neutrophils isolated from healthy subjects, both at baseline and upon stimulation with calcium ionophore. For the clinical trial, participants were healthy adults 30–55 years of age with a reported EPA+DHA consumption of ≤300 mg/day randomly assigned to parallel groups receiving daily oil capsule supplements for a period of 4 months containing either 1.4 g of EPA+DHA (active condition, n = 24) or identical appearing soybean oil (control condition, n = 21). Participants and laboratory technicians remained blinded to treatment assignments.

Results

5-lypoxygenase-dependent endogenous generation of 7-oxo-DHA, 7-oxo-DPA and 5-oxo-EPA and their hydroxy precursors is reported in human neutrophils stimulated with calcium ionophore and phorbol 12-myristate 13-acetate (PMA). Dietary EPA+DHA supplementation significantly increased the formation of 7-oxo-DHA and 5-oxo-EPA, with no significant modulation of arachidonic acid (AA) metabolite levels.

Conclusions

The endogenous detection of these electrophilic ω-3 fatty acid ketone derivatives supports the precept that the benefit of ω-3 PUFA-rich diets can be attributed to the generation of electrophilic oxygenated metabolites that transduce anti-inflammatory actions rather than the suppression of pro-inflammatory AA metabolites.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00663871","term_id":"NCT00663871"}}NCT00663871     

Efficacy of Berberine in Patients with Non-Alcoholic Fatty Liver Disease

Objectives

A randomized, parallel controlled, open-label clinical trial was conducted to evaluate the effect of a botanic compound berberine (BBR) on NAFLD.

Methods

A randomized, parallel controlled, open-label clinical trial was conducted in three medical centers (NIH Registration number: NCT00633282). A total of 184 eligible patients with NAFLD were enrolled and randomly received (i) lifestyle intervention (LSI), (ii) LSI plus pioglitazone (PGZ) 15mg qd, and (iii) LSI plus BBR 0.5g tid, respectively, for 16 weeks. Hepatic fat content (HFC), serum glucose and lipid profiles, liver enzymes and serum and urine BBR concentrations were assessed before and after treatment. We also analyzed hepatic BBR content and expression of genes related to glucose and lipid metabolism in an animal model of NAFLD treated with BBR.

Results

As compared with LSI, BBR treatment plus LSI resulted in a significant reduction of HFC (52.7% vs 36.4%, p = 0.008), paralleled with better improvement in body weight, HOMA-IR, and serum lipid profiles (all p<0.05). BBR was more effective than PGZ 15mg qd in reducing body weight and improving lipid profile. BBR-related adverse events were mild and mainly occurred in digestive system. Serum and urine BBR concentrations were 6.99ng/ml and 79.2ng/ml, respectively, in the BBR-treated subjects. Animal experiments showed that BBR located favorably in the liver and altered hepatic metabolism-related gene expression.

Conclusion

BBR ameliorates NAFLD and related metabolic disorders. The therapeutic effect of BBR on NAFLD may involve a direct regulation of hepatic lipid metabolism.

Trial Registration

ClinicalTrials.gov NCT00633282     

ITPA Genotypes Predict Anemia but Do Not Affect Virological Response with Interferon-Free Faldaprevir,Deleobuvir, and Ribavirin for HCV Infection

Background & Aim

Whether inosine triphosphatase (ITPA) gene polymorphisms predict anemia during interferon-free therapy in chronic hepatitis C virus (HCV)-infected patients is unknown. We examined the relationship between two ITPA polymorphisms, anemia, and sustained virological response 12 weeks post-treatment (SVR12) in patients receiving the NS3/4A protease inhibitor faldaprevir, the non-nucleoside polymerase inhibitor deleobuvir, and ribavirin.

Methods

HCV genotype 1-infected, treatment-naïve patients (N = 362) were randomized and treated in one of five treatment arms with faldaprevir and deleobuvir with or without ribavirin. Two ITPA polymorphisms (rs1127354 and rs6051702) were genotyped and defined as ITPA-deficient (rs1127354 AA or AC; rs6051702 CC or CA) or ITPA-non-deficient (rs1127354 CC; rs6051702 AA) according to their association with ITPA deficiency. Baseline and on-treatment variables associated with anemia and SVR12 were identified using logistic regression.

Results

In the pooled ribavirin-containing arms, 10.1% (32/316) of patients experienced on-treatment hemoglobin <10 g/dL, and 32.6% (103/316) experienced on-treatment hemoglobin <10 g/dL or a change from baseline ≥3.5 g/dL. Of the latter group, 99% (102/103) had the ITPA-non-deficient rs1127354 genotype. Other variables associated with on-treatment hemoglobin <10 g/dL or a decrease ≥3.5 g/dL were age, baseline hemoglobin, rs6051702 genotype, and plasma ribavirin concentration. In a multivariate analysis, high plasma ribavirin concentration, low baseline hemoglobin, HCV genotype 1b, and IL28B genotype CC were associated with higher SVR12.

Conclusions

The ITPA rs1127354 CC and rs6051702 AA genotypes may predict ribavirin-induced anemia during treatment with interferon-free, ribavirin-containing regimens. With this interferon-free regimen, SVR was associated with ribavirin levels, but not with anemia or ITPA genotypes.

Trial Registration

ClinicalTrials.gov: {"type":"clinical-trial","attrs":{"text":"NCT01132313","term_id":"NCT01132313"}}NCT01132313     

Dynamic Changes in Amino Acid Concentration Profiles in Patients with Sepsis

Objectives

The goal of this work was to explore the dynamic concentration profiles of 42 amino acids and the significance of these profiles in relation to sepsis, with the aim of providing guidance for clinical therapies.

Methods

Thirty-five critically ill patients with sepsis were included. These patients were further divided into sepsis (12 cases) and severe sepsis (23 cases) groups or survivor (20 cases) and non-survivor (15 cases) groups. Serum samples from the patients were collected on days 1, 3, 5, 7, 10, and 14 following intensive care unit (ICU) admission, and the serum concentrations of 42 amino acids were measured.

Results

The metabolic spectrum of the amino acids changed dramatically in patients with sepsis. As the disease progressed further or with poor prognosis, the levels of the different amino acids gradually increased, decreased, or fluctuated over time. The concentrations of sulfur-containing amino acids (SAAs), especially taurine, decreased significantly as the severity of sepsis worsened or with poor prognosis of the patient. The serum concentrations of SAAs, especially taurine, exhibited weak negative correlations with the Sequential Organ Failure Assessment (SOFA) (r=-0.319) and Acute Physiology and Chronic Health Evaluation (APACHE) II (r=-0.325) scores. The areas under the receiver operating characteristic curves of cystine, taurine, and SAA levels and the SOFA and APACHE II scores, which denoted disease prognosis, were 0.623, 0.674, 0.678, 0.86, and 0.857, respectively.

Conclusions

Critically ill patients with disorders of amino acid metabolism, especially of SAAs such as cystine and taurine, may provide an indicator of the need for the nutritional support of sepsis in the clinic.

Trial Registration

ClinicalTrial.gov identifier NCT01818830.     

Characterization of a human 12/15-lipoxygenase promoter variant associated with atherosclerosis identifies vimentin as a promoter binding protein

Background

Sequence variation in the human 12/15 lipoxygenase (ALOX15) has been associated with atherosclerotic disease. We functionally characterized an ALOX15 promoter polymorphism, rs2255888, previously associated with carotid plaque burden.

Methodology/Principal Findings

We demonstrate specific in vitro and in vivo binding of the cytoskeletal protein, vimentin, to the ALOX15 promoter. We show that the two promoter haplotypes carrying alternate alleles at rs2255888 exhibit significant differences in promoter activity by luciferase reporter assay in two cell lines. Differences in in-vitro vimentin-binding to and formation of DNA secondary structures in the polymorphic promoter sequence are also detected by electrophoretic mobility shift assay and biophysical analysis, respectively. We show regulation of ALOX15 protein by vimentin.

Conclusions/Significance

This study suggests that vimentin binds the ALOX15 promoter and regulates its promoter activity and protein expression. Sequence variation that results in changes in DNA conformation and vimentin binding to the promoter may be relevant to ALOX15 gene regulation.     

Development and Characterization of an Effective Food Allergy Model in Brown Norway Rats

Background

Food allergy (FA) is an adverse health effect produced by the exposure to a given food. Currently, there is no optimal animal model of FA for the screening of immunotherapies or for testing the allergenicity of new foods.

Objective

The aim of the present study was to develop an effective and rapid model of FA in Brown Norway rats. In order to establish biomarkers of FA in rat, we compared the immune response and the anaphylactic shock obtained in this model with those achieved with only intraperitoneal immunization.

Methods

Rats received an intraperitoneal injection of ovalbumin (OVA) with alum and toxin from Bordetella pertussis, and 14 days later, OVA by oral route daily for three weeks (FA group). A group of rats receiving only the i.p. injection (IP group) were also tested. Serum anti-OVA IgE, IgG1, IgG2a, IgG2b and IgA antibodies were quantified throughout the study. After an oral challenge, body temperature, intestinal permeability, motor activity, and mast cell protease II (RMCP-II) levels were determined. At the end of the study, anti-OVA intestinal IgA, spleen cytokine production, lymphocyte composition of Peyer’s patches and mesenteric lymph nodes, and gene expression in the small intestine were quantified.

Results

Serum OVA-specific IgG1, IgG2a and IgG2b concentrations rose with the i.p. immunization but were highly augmented after the oral OVA administration. Anti-OVA IgE increased twofold during the first week of oral OVA gavage. The anaphylaxis in both IP and FA groups decreased body temperature and motor activity, whereas intestinal permeability increased. Interestingly, the FA group showed a much higher RMCP II serum protein and intestinal mRNA expression.

Conclusions

These results show both an effective and relatively rapid model of FA assessed by means of specific antibody titres and the high production of RMCP-II and its intestinal gene expression.     

Mechanisms Regulating Insulin Response to Intragastric Glucose in Lean and Non-Diabetic Obese Subjects: A Randomized,Double-Blind,Parallel-Group Trial

Background/Objectives

The changes in blood glucose concentrations that result from an oral glucose challenge are dependent on the rate of gastric emptying, the rate of glucose absorption and the rate of insulin-driven metabolism that include the incretins, glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide-1 (GLP-1). The rate of insulin-driven metabolism is clearly altered in obese subjects, but it is controversial which of these factors is predominant. We aimed to quantify gastric emptying, plasma insulin, C-peptide, glucagon and glucose responses, as well as incretin hormone secretions in obese subjects and healthy controls during increasing glucose loads.

Subjects/Methods

The study was conducted as a randomized, double-blind, parallel-group trial in a hospital research unit. A total of 12 normal weight (6 men and 6 women) and 12 non-diabetic obese (BMI > 30, 6 men and 6 women) participants took part in the study. Subjects received intragastric loads of 10 g, 25 g and 75 g glucose dissolved in 300 ml tap water.

Results

Main outcome measures were plasma GLP-1 and GIP, plasma glucagon, glucose, insulin, C-peptide and gastric emptying. The primary findings are: i) insulin resistance (P < 0.001) and hyperinsulinemia (P < 0.001); ii) decreased insulin disposal (P < 0.001); iii) trend for reduced GLP-1 responses at 75 g glucose; and iv) increased fasting glucagon levels (P < 0.001) in obese subjects.

Conclusions

It seems that, rather than changes in incretin secretion, fasting hyperglucagonemia and consequent hyperglycemia play a role in reduced disposal of insulin, contributing to hyperinsulinemia and insulin resistance.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01875575","term_id":"NCT01875575"}}NCT01875575     

Increasing Maternal or Post-Weaning Folic Acid Alters Gene Expression and Moderately Changes Behavior in the Offspring

Background

Studies have indicated that altered maternal micronutrients and vitamins influence the development of newborns and altered nutrient exposure throughout the lifetime may have potential health effects and increased susceptibility to chronic diseases. In recent years, folic acid (FA) exposure has significantly increased as a result of mandatory FA fortification and supplementation during pregnancy. Since FA modulates DNA methylation and affects gene expression, we investigated whether the amount of FA ingested during gestation alters gene expression in the newborn cerebral hemisphere, and if the increased exposure to FA during gestation and throughout the lifetime alters behavior in C57BL/6J mice.

Methods

Dams were fed FA either at 0.4 mg or 4 mg/kg diet throughout the pregnancy and the resulting pups were maintained on the diet throughout experimentation. Newborn pups brain cerebral hemispheres were used for microarray analysis. To confirm alteration of several genes, quantitative RT-PCR (qRT-PCR) and Western blot analyses were performed. In addition, various behavior assessments were conducted on neonatal and adult offspring.

Results

Results from microarray analysis suggest that the higher dose of FA supplementation during gestation alters the expression of a number of genes in the newborns’ cerebral hemispheres, including many involved in development. QRT-PCR confirmed alterations of nine genes including down-regulation of Cpn2, Htr4, Zfp353, Vgll2 and up-regulation of Xist, Nkx6-3, Leprel1, Nfix, Slc17a7. The alterations in the expression of Slc17a7 and Vgll2 were confirmed at the protein level. Pups exposed to the higher dose of FA exhibited increased ultrasonic vocalizations, greater anxiety-like behavior and hyperactivity. These findings suggest that although FA plays a significant role in mammalian cellular machinery, there may be a loss of benefit from higher amounts of FA. Unregulated high FA supplementation during pregnancy and throughout the life course may have lasting effects, with alterations in brain development resulting in changes in behavior.     

Increased Missense Mutation Burden of Fatty Acid Metabolism Related Genes in Nunavik Inuit Population

Background

Nunavik Inuit (northern Quebec, Canada) reside along the arctic coastline where for generations their daily energy intake has mainly been derived from animal fat. Given this particular diet it has been hypothesized that natural selection would lead to population specific allele frequency differences and unique variants in genes related to fatty acid metabolism. A group of genes, namely CPT1A, CPT1B, CPT1C, CPT2, CRAT and CROT, encode for three carnitine acyltransferases that are important for the oxidation of fatty acids, a critical step in their metabolism.

Methods

Exome sequencing and SNP array genotyping were used to examine the genetic variations in the six genes encoding for the carnitine acyltransferases in 113 Nunavik Inuit individuals.

Results

Altogether ten missense variants were found in genes CPT1A, CPT1B, CPT1C, CPT2 and CRAT, including three novel variants and one Inuit specific variant CPT1A p.P479L (rs80356779). The latter has the highest frequency (0.955) compared to other Inuit populations. We found that by comparison to Asians or Europeans, the Nunavik Inuit have an increased mutation burden in CPT1A, CPT2 and CRAT; there is also a high level of population differentiation based on carnitine acyltransferase gene variations between Nunavik Inuit and Asians.

Conclusion

The increased number and frequency of deleterious variants in these fatty acid metabolism genes in Nunavik Inuit may be the result of genetic adaptation to their diet and/or the extremely cold climate. In addition, the identification of these variants may help to understand some of the specific health risks of Nunavik Inuit.     

Effects of Nucleotides Supplementation of Infant Formulas on Plasma and Erythrocyte Fatty Acid Composition: A Meta-Analysis

Objective

Nucleotides (NTs) have been added to infant formulas for several years due to their health benefits. However, studies have reported inconsistent findings regarding the association between NTs and fatty acid (FA) composition. A meta-analysis was performed to assess the effects of NTs supplementation of infant formula on erythrocyte and plasma FA composition.

Methods

Randomized controlled trials that evaluated the association between NTs supplementation and FA composition and were published before October 2014 were included. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. Heterogeneity was assessed using Q and I ² tests.

Results

Eight studies (364 infants) were included in the meta-analysis. NTs supplementation did not affect the concentrations of total saturated FAs (SMD= 0.05; 95% CI= -0.23–0.32; P = 0.75) or total monounsaturated FAs (SMD= -0.01; 95% CI= -0.28–0.27; P = 0.95) in erythrocyte membranes. Erythrocyte total n-3 (SMD= 0.15; 95% CI= -0.11–0.41; P = 0.27) and n-6 PUFA (SMD= -0.16; 95% CI= -0.42–0.10, P = 0.22) concentrations did not increase with NTs supplementation. The concentrations of erythrocyte n-3 PUFA (18:3, 20:5, 22:5, and 22:6) and n-6 PUFA (18:2, 20:3, 20:4, and 22:4) were not affected by NTs supplementation. NTs significantly increased plasma concentrations of 18:2 n-6 (SMD= 0.90; 95% CI= 0.47–1.33; P < 0.0001), 20:3 n-6 (SMD= 0.56; 95% CI= 0.14–0.97; P = 0.009), and 20:4 n-6 PUFA (SMD= 0.92; 95% CI= 0.50–1.35; P < 0.0001), and significantly decreased the concentration of plasma 18:3 n-3 PUFA (SMD= -0.60; 95% CI -1.12 to -0.09; P = 0.02). No effect was obtained on plasma 20:2 n-6 PUFA concentrations (SMD= 0.06; 95 % CI, -1.03 to -0.2; P = 0.93).

Conclusions

Our meta-analysis revealed that NTs supplementation significantly increased plasma 18:2 n-6, 20:3 n-6, and 20:4 n-6 PUFA concentrations in infants, but did not affect erythrocyte FA composition.     

Fasting Whole Blood Fatty Acid Profile and Risk of Type 2 Diabetes in Adults: A Nested Case Control Study

Objective

to determine the association of fasting whole blood fatty acid concentrations with incidence of type 2 diabetes in adults.

Methods

A nested case-control study of 187 subjects from a cohort of men and women aged 55–85 years from the Hunter Region, New South Wales, Australia. Fasting whole blood fatty acids were measured using gas chromatography and incidence of type 2 diabetes was ascertained by self-reported questionnaire at the study follow-up.

Results

After adjustment for potential confounding variables, positive associations with type 2 diabetes were seen for dihomo-gamma-linolenic acid (DGLA) (OR = 1.04, 95% CI:1.01–1.07, P = 0.01); arachidonic acid (ARA) (OR = 1.01, 95% CI:1.00–1.01, P = 0.002); alpha-linolenic acid (ALA) (OR = 1.10, 95% CI: 1.03–1.18, P = 0.01); eicosapentaenoic acid (EPA) (OR = 1.05, 95% CI:1.02–1.08, P = 0.001); and docosahexaenoic acid (DHA) (OR = 1.03, 95% CI:1.02–1.05, P<0.0001). Lignoceric acid is significantly associated with lower type 2 diabetes risk (OR = 0.95, 95% CI: 0.92–0.99, P = 0.01).

Conclusion

These data suggest that higher fasting whole blood concentrations of omega-6 polyunsaturated fatty acids (n-6PUFA) (ARA and DGLA) as well as omega-3 polyunsaturated fatty acid (n-3PUFA) (ALA, EPA, and DHA) are associated with an increased risk of diabetes, whereas increased fasting whole blood concentrations of lignoceric acid is inversely associated with diabetes risk.     

Effect of trans Fatty Acid Intake on LC-MS and NMR Plasma Profiles

Background

The consumption of high levels of industrial trans fatty acids (TFA) has been related to cardiovascular disease, diabetes and sudden cardiac death but the causal mechanisms are not well known. In this study, NMR and LC-MS untargeted metabolomics has been used as an approach to explore the impact of TFA intake on plasma metabolites.

Methodology/Principal Findings

In a double-blinded randomized controlled parallel-group study, 52 overweight postmenopausal women received either partially hydrogenated soybean oil, providing 15.7 g/day of TFA (trans18:1) or control oil with mainly oleic acid for 16 weeks. Subsequent to the intervention period, the subjects participated in a 12-week dietary weight loss program. Before and after the TFA intervention and after the weight loss programme, volunteers participated in an oral glucose tolerance test. PLSDA revealed elevated lipid profiles with TFA intake. NMR indicated up-regulated LDL cholesterol levels and unsaturation. LC-MS profiles demonstrated elevated levels of specific polyunsaturated (PUFA) long-chain phosphatidylcholines (PCs) and a sphingomyelin (SM) which were confirmed with a lipidomics based method. Plasma levels of these markers of TFA intake declined to their low baseline levels after the weight loss program for the TFA group and did not fluctuate for the control group. The marker levels were unaffected by OGTT.

Conclusions/Significance

This study demonstrates that intake of TFA affects phospholipid metabolism. The preferential integration of trans18:1 into the sn-1 position of PCs, all containing PUFA in the sn-2 position, could be explained by a general up-regulation in the formation of long-chain PUFAs after TFA intake and/or by specific mobilisation of these fats into PCs. NMR supported these findings by revealing increased unsaturation of plasma lipids in the TFA group. These specific changes in membrane lipid species may be related to the mechanisms of TFA-induced disease but need further validation as risk markers.

Trial registration

Registered at clinicaltrials.gov as {"type":"clinical-trial","attrs":{"text":"NCT00655902","term_id":"NCT00655902"}}NCT00655902     

Fish-Free Diet in Patients with Phenylketonuria Is Not Associated with Early Atherosclerotic Changes and Enhanced Platelet Activation

Background and Purpose

Since patients with phenylketonuria (PKU) have to follow a lifelong restriction of natural protein to lower phenylalanine-intake, they never eat fish. This diet may lead to a chronic deficit of omega-3 and omega-6 fatty acids with the risk of early atherosclerotic changes. The aim of the study was to analyse the fatty acid profile of PKU patients and to correlate the results with surrogate markers of early atherosclerotic changes [enhanced carotid intima media thickness (CIMT) and ß-stiffness index] and platelet activation.

Methods

In 43 PKU patients and in 58 healthy controls we prospectively examined the fatty acid profile, CIMT, ß-stiffness index and platelet activation (flow cytometric determination of markers of platelet activation). CIMT was measured bilaterally by ultrasound. CIMT _mean was defined as the mean value of the sum of CIMT _left and CIMT _right.

Results

Despite of lower HDL-cholesterol and higher triglyceride concentrations in the PKU group, there was no significant difference in the omega-6 or omega-3 fatty acid profile, CIMT, ß-stiffness index between both groups. Platelet activation was not enhanced in the PKU group.

Conclusions

Fish-free diet does not induce early atherosclerotic changes or enhanced platelet activation in PKU patients.     

Effects of DHA-rich n-3 fatty acid supplementation on gene expression in blood mononuclear leukocytes: the OmegAD study

Background

Dietary fish oil, rich in n-3 fatty acids (n-3 FAs), e.g. docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), regulate inflammatory reactions by various mechanisms, e.g. gene activation. However, the effects of long-term treatment with DHA and EPA in humans, using genome wide techniques, are poorly described. Hence, our aim was to determine the effects of 6 mo of dietary supplementation with an n-3 FA preparation rich in DHA on global gene expression in peripheral blood mononuclear cells.

Methods and Findings

In the present study, blood samples were obtained from a subgroup of 16 patients originating from the randomized double-blind, placebo-controlled OmegAD study, where 174 Alzheimer disease (AD) patients received daily either 1.7 g of DHA and 0.6 g EPA or placebo for 6 months. In blood samples obtained from 11 patients receiving n-3 FA and five placebo, expressions of approximately 8000 genes were assessed by gene array. Significant changes were confirmed by real-time PCR. At 6 months, the n-3 FAs group displayed significant rises of DHA and EPA plasma concentrations, as well as up- and down-regulation of nine and ten genes, respectively, was noticed. Many of these genes are involved in inflammation regulation and neurodegeneration, e.g. CD63, MAN2A1, CASP4, LOC399491, NAIP, and SORL1 and in ubiqutination processes, e.g. ANAPC5 and UBE2V1. Down-regulations of ANAPC5 and RHOB correlated to increases of plasma DHA and EPA levels.

Conclusions

We suggest that 6 months of dietary n-3 FA supplementation affected expression of genes that might influence inflammatory processes and could be of significance for AD.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00211159","term_id":"NCT00211159"}}NCT00211159