Prostaglandins, Leukotrienes and Essential Fatty Acids

Editorial Board

2012-04-01

Changes in rat n-3 and n-6 fatty acid composition during pregnancy are associated with progesterone concentrations and hepatic FADS2 expression

C.E. Childs, S.P. Hoile, G.C. Burdge, P.C. Calder — 2012-04-11

Abstract: The mechanisms responsible for changes to long-chain polyunsaturated fatty acid (LC PUFA) status during pregnancy have not been fully elucidated. Tissue samples were collected from virgin and pregnant (day 12 and 20) female rats. LC PUFA status, sex hormone concentrations and hepatic mRNA expression of FADS1, FADS2 and elongase were assessed. Day 20 gestation females had higher plasma and liver docosahexaenoic acid and lower arachidonic acid content than virgin females (P<0.05). There was higher FADS2 mRNA expression during pregnancy (P=0.051). Progesterone and oestradiol concentrations positively correlated with hepatic FADS2 mRNA expression (P=0.043, P=0.004). Progesterone concentration positively correlated with hepatic n-6 docosapentaenoic acid content (P=0.006), and inversely correlated with intermediates in LC PUFA synthesis including n-3 docosapentaenoic acid, γ-linolenic acid and 20:2n-6 (P<0.05). Changes in progesterone and oestradiol during pregnancy may promote the synthesis of LC PUFA via increased FADS2 expression.

A radioenzymatic assay to identify three groups of phospholipase A2 in platelets

2012-04-12

Abstract: Phospholipases A2 (PLA2) are key enzymes in membrane metabolism. The release of fatty acids and lysophospholipids by PLA2 activates several intra-cellular second messenger cascades that regulate a wide variety of physiological responses. The aim of the present study is to describe a radioenzymatic assay to determine the activity of three main PLA2 subtypes in platelets, namely extracellular calcium-dependent PLA2 (sPLA2) and intracellular calcium-dependent (cPLA2) and calcium-independent PLA2 (iPLA2). The differentiation of these distinct PLA2 subtypes was based on the enzyme substrate preference (arachdonic acid or palmitoyl acid) and calcium concentration. Our results indicate that this new assay is feasible, precise and specific to measure the activity of the aforementioned subtypes of PLA2. Therefore, this protocol can be used to investigate modifications of PLA2 homeostasis in distinct biological models addressing the pathophysiology of many medical and neuropsychiatric disorders such as schizophrenia and Alzheimer's disease.

Associations between omega-3 poly-unsaturated fatty acids from fish consumption and severity of depressive symptoms: An analysis of the 2005–2008 National Health and Nutrition Examination Survey

2012-04-03

Abstract: Fish is the primary source of dietary omega-3 poly-unsaturated fatty acids EPA and DHA, which have been reported to reduce depressive symptoms in clinical trials. We assessed the association between fish consumption and depressive symptoms in a nationally representative sample of 10,480 adults from the 2005–2008 National Health and Nutrition Examination Survey. Depressive symptoms were classified by severity using the Patient Health Questionnaire. Fish meal consumption reported in 30-day food frequency questionnaires, and EPA+DHA intake computed from 24-h dietary recalls were evaluated in relation to depressive symptoms using multivariable ordinal logistic regression. Consumption of breaded fish showed an increased risk of greater depressive symptom severity, while all fish, non-breaded fish, and shell fish were not associated. Any EPA+DHA intake was significantly associated with fewer depressive symptoms. Exposure-response analyses revealed no clear patterns for any intake measures. Inconsistent patterns of associations in our study may be partially explained by exposure misclassification.

Red blood cell fatty acids are associated with depression in a case-control study of adolescents

2012-04-05

Abstract: Introduction: Epidemiological studies suggest that reduced intakes and/or blood levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are associated with increased risk for depression in adults, but data on adolescents are scarce. The objective of this study was to determine whether red blood cell (RBC) levels of EPA+DHA (the omega-3 index) and/or the overall RBC fatty acid profile differ between depressed adolescents (cases) and non-depressed adolescents (controls).Patients and Methods: We measured the RBC fatty acid composition of cases admitted to the hospital for depression (n=150) and compared it to that of controls (n=161).Results: Cases and controls had similar ages, gender proportions, and body mass index (BMI) distributions, but there was a significant difference in racial/ethnic composition due to differences in recruitment sites. The unadjusted odds ratio for case status was 0.72 (95% CI; 0.55–0.95) for a 1% absolute increase in the omega-3 index. A multivariable logistic regression model was used to determine which fatty acids were useful in classifying cases and controls; BMI, age, gender, and race/ethnicity were forced into the model. Seven fatty acids were selected (DHA, myristic, stearic, oleic, trans linoleic, trans palmitoleic, and alpha-linolenic acids) to optimize the model fit to the data. In the adjusted model, the odds ratio was 0.67 (95% CI; 0.49–0.93) for a 1 SD increase in DHA. Adding the seven fatty acid profile to the basic model increased the area under the ROC curve by 12.6% (7.5%–17.6%).Discussion and Conclusion: These findings support the hypothesis that adolescent depression is associated with a perturbed RBC fatty acid pattern which includes a reduced omega-3 index. Intervention studies with EPA and DHA should be conducted in this vulnerable population for which few, safe therapeutic options currently exist.

Dietary lipids during early pregnancy differently influence adipose tissue metabolism and fatty acid composition in pregnant rats with repercussions on pup's development

2012-03-26

Abstract: Pregnant rats received soybean (SO), olive (OO), fish (FO) and linseed (LO) oil diets from conception to d12 of gestation (early diets) and standard diet thereafter. At d12 and d20 the lipoprotein lipase (LPL) activity was evaluated in maternal adipose tissues (ATs). Fatty Acid (FA) profile was determined in maternal lumbar AT (LAT), in milk and in pup's plasma and brain. LPL activity was higher in ATs at d12 than d20, all groups presenting hypertriglyceridemia at d20. At d12, the LO diet resulted higher LPL activity and incorporation of 18:3 n−3 into LAT. FA profile in maternal LAT at d20 and colostrum was similar to early diets, reflected also in FA composition of pup's plasma. In FO, brain phospholipids had higher 22:6 n−3 without affecting arachidonic acid. These results suggest that specifics dietary FA in early pregnancy modulates lipid metabolism and the provision of LC-PUFA in milk and pups brain.

Cis-vaccenic acid and the Framingham risk score predict chronic kidney disease: The multi-ethnic study of atherosclerosis (MESA)

2012-03-15

Abstract: Introduction: Data on the associations of fatty acids with chronic kidney disease (CKD) are sparse.Materials and methods: We performed a cross-sectional study of 2792 men and women from the MESA cohort of African–American, Caucasian, Chinese and Hispanic adults without known cardiovascular disease. Plasma phospholipid fatty acid proportions were associated with estimated glomerular filtration rate (eGFR) and the albumin/creatinine ratio.Results: Cis-vaccenic acid (18:1n−7), adjusted for other fatty acids using multivariate logistic regression (CI: 1.0–1.4), and step-wise logistic regression (CI: 1.02–1.42), was positively associated with reduced eGFR. The Framingham Risk Score, when adjusting for fatty acid proportions and demographic factors, was positively associated with CKD as measured by the eGFR and the albumin/creatinine ratio.Discussion and conclusions: Plasma phospholipid proportions of the 18 carbon monounsaturated cis-vaccenic acid {18:1n−7}) and the Framingham Risk Score are associated with kidney function. The potential role of 18:1n−7 in the development of CKD warrants further investigation.

Motor, mental and behavioral developments in infancy are associated with fatty acid pattern in breast milk and plasma of premature infants

K.-G. Sabel, B. Strandvik, M. Petzold, C. Lundqvist-Persson — 2012-03-22

Abstract: The objective of this study was to investigate any association between infants' early development and PUFA concentrations in early breast milk and infants' plasma phospholipids at 44 weeks gestational age. Fifty-one premature infants were included. The quality of general movement was assessed at 3 months, and motor, mental and behavioral development at 3, 6, 10 and 18 months corrected age using Bayley's Scales of Infant Development (BSID-II).Linoleic acid, the major n-6/n-3 FA ratios, Mead acid and the EFA deficiency index in early breast milk were negatively associated with development up to 18 months of age. DHA and AA, respectively, in infants' plasma phospholipids was positively, but the AA/DHA ratio negatively, associated with development from 6 to 18 months of age.Our data suggest that the commonly found high n-6 concentration in breast milk is associated with less favorable motor, mental and behavioral development up to 18 months of age.

Gestational age dependent changes of the fetal brain, liver and adipose tissue fatty acid compositions in a population with high fish intakes

2012-03-19

Abstract: Introduction: There are no data on the intrauterine fatty acid (FA) compositions of brain, liver and adipose tissue of infants born to women with high fish intakes.Subjects and methods: We analyzed the brain (n=18), liver (n=14) and adipose tissue (n=11) FA compositions of 20 stillborn infants with different gestational ages (range 8–38 weeks) born to Tanzanian women with low linoleic acid (LA) intakes and high intakes of docosahexaenoic (DHA) and arachidonic (AA) acids from local fish.Results and discussion: With advancing gestation, brain saturated-FA (SAFA; in g/100g FA), polyunsaturated-FA (PUFA), DHA, 20:3ω6, 22:4ω6 and 22:5ω6 increased, while monounsaturated-FA (MUFA), 20:3ω9, 22:3ω9 and AA decreased. Decreasing brain AA might be caused by increasing AA-metabolism to 20:3ω6, 22:4ω6 and 22:5ω6. In the liver, SAFA, PUFA and LA increased, while MUFA decreased with gestation. The steep increase of (mostly de novo synthesized) SAFA in adipose tissue coincided with relative decreases of MUFA, PUFA, DHA, LA and AA with advancing gestation. Compared to Western infants, the currently studied African infants had higher DHA, lower AA, and a higher DHA/AA-ratio in brain and adipose tissue, while the LA content of adipose tissue was lower.Conclusion: The low LA and high DHA and AA intakes by the mothers of these infants might support optimal α-linolenic (ALA) vs. LA competition for Δ5D and Δ6D-activities and DHA vs. AA antagonism. Conversely, the Western diet, characterized by high LA and lower DHA and AA intakes, might disturb these evolutionary conserved mechanisms aiming at an optimal ω3/ω6-balance.

Fatty acid compositions of preterm and term colostrum, transitional and mature milks in a sub-Saharan population with high fish intakes

2012-03-19

Abstract: Background: There are no data on the fatty acid (FA) compositions of preterm and term milks for sub-Saharan African populations with advancing lactation. However, it is generally acknowledged that our ancestors evolved in sub-Saharan East-Africa, where they inhabited the land-water ecosystems.Methods: We compared the FA-compositions of preterm (28–36 weeks) and term (37–42) colostrum (2–5 day), transitional (6–15) and mature (16–56) milks in rural African women with stable dietary habits and lifelong high freshwater fish intakes.Results: From colostrum to mature milk: the median docosahexaenoic acid (DHA) content decreased from 1.11 to 0.75; and arachidonic acid (AA) from 0.93 to 0.69g% in preterm milk. In term milk, DHA decreased from 0.81 to 0.53 and AA from 1.08 to 0.55g%. Medium-chain saturated-FA (MCSAFA) increased from 16.9 to 33.7, and 7.92–29.0g%, while mono-unsaturated FA (MUFA) decreased from 32.5 to 22.6, and 40.0–26.5g%, in preterm and term milk, respectively. Consistent with the literature, preterm colostrum contained higher DHA and MCSAFA, and lower MUFA compared to term colostrum. These differences vanished rapidly with advancing lactation. MUFA and MCSAFA were inversely related.Conclusions: The presently found DHA in preterm colostrum and mature milks and AA in premature mature milk proved the highest reported in the literature so far, as derived from analysis with capillary GC-columns. We confirmed the much higher MCSAFA and lower MUFA contents in milk of rural African, compared to Westernized women. The milk FA composition of this traditional population might show us the FA composition on which our species evolved and consequently to which our genome has become adapted to optimally support (infant) health.

Letter to the Editor

Emiko Saito, Tomoo Okada, Fujihiko Iwata, Yohei Kitamura — 2012-04-04

Hofacer et al. investigated the mechanisms mediating the effect of n-3 fatty acids on triglyceride (TG) biosynthesis in rats, demonstrating that n-3 fatty acid deficiency up-regulates liver stearoyl-CoA desaturase (SCD)-1 mRNA expression and activity indices (16:1/16:0 and 18:1/18:0 ratios) and increase plasma TG concentrations in vivo. These results were very interesting to us, because we studied the relationship among docosahexaenoic acid (DHA) content in plasma phospholipids, SCD activity indices and the components of metabolic syndrome in obese children .