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The effects of omega-3 fatty acids on the adaptive immune response have mainly been analysed in vitro with varying results. How omega-3 fatty acids affect the adaptive immune response in vivo is largely unknown. This study examined the effects of dietary fish oil on the adaptive immune response in antigen-induced inflammation in mice, focusing on its effects on B cells and B cell subsets. Mice were fed a control diet with or without 2.8% fish oil, immunized twice with methylated BSA (mBSA) and peritonitis induced by intraperitoneal injection of mBSA. Serum, spleen and peritoneal exudate were collected prior to and at different time points after induction of peritonitis. Serum levels of mBSA-specific antibodies were determined by ELISA and the number of peritoneal and splenic lymphocytes by flow cytometry. The levels of germinal center B cells and IgM(+), IgG(+) and CD138(+) cells in spleen were evaluated by immunoenzyme staining. Mice fed the fish oil diet had more peritoneal B1 cells, more IgM(+) cells in spleen and higher levels of serum mBSA-specific IgM antibodies compared with that in mice fed the control diet. However, dietary fish oil did not affect the number of peritoneal B2 cells, splenic IgG(+) or CD138(+) cells or serum levels of mBSA-specific IgG antibodies in mice with mBSA-induced peritonitis. These results indicate that dietary fish oil can enhance the adaptive immune response, specifically the B1 cell response, which may lead to better protection against secondary infection as well as improvement in reaching homeostasis following antigenic challenge., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Previous research has demonstrated that diabetes induces learning and memory deficits. However, the mechanism of memory impairment induced by diabetes is poorly understood. Dietary fatty acids, especially polyunsaturated fatty acids, have been shown to enhance learning and memory and prevent memory deficits in various experimental conditions. The present study investigated the effects of fish oil supplementation on the lipid peroxidation, inflammation and neuron apoptosis in the hippocampus of streptozotocin (STZ)-induced diabetes rats. The effects of diabetes and fish oil treatment on the spatial learning and memory were also evaluated using the Morris Water Maze. STZ-induced diabetes impaired spatial learning and memory of rats, which was associated with the inflammation, oxidative stress and apoptosis of hippocampal neurons. Fish oil administration ameliorated cognitive deficit, reduced oxidative stress and tumor necrosis factor α (TNF-α), protected the hippocampal neurons by increasing Protein Kinase B (AKT) phosphorylation and decreasing caspase-9 expression. These results suggested that the principle mechanisms involved in the antidiabetic and neuroprotective effect of fish oil were its antioxidant, anti-inflammatory and anti-apoptosis potential, supporting a potential role for fish oil as an adjuvant therapy for the prevention and treatment of diabetic complications., (Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.)

Lipid content and composition in aquafeeds have changed rapidly as a result of the recent drive to replace ecologically limited marine ingredients, fishmeal and fish oil (FO). Terrestrial plant products are the most economic and sustainable alternative; however, plant meals and oils are devoid of physiologically important cholesterol and long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic (EPA), docosahexaenoic (DHA) and arachidonic (ARA) acids. Although replacement of dietary FO with vegetable oil (VO) has little effect on growth in Atlantic salmon (Salmo salar), several studies have shown major effects on the activity and expression of genes involved in lipid homeostasis. In vertebrates, sterols and LC-PUFA play crucial roles in lipid metabolism by direct interaction with lipid-sensing transcription factors (TFs) and consequent regulation of target genes. The primary aim of the present study was to elucidate the role of key TFs in the transcriptional regulation of lipid metabolism in fish by transfection and overexpression of TFs. The results show that the expression of genes of LC-PUFA biosynthesis (elovl and fads2) and cholesterol metabolism (abca1) are regulated by Lxr and Srebp TFs in salmon, indicating highly conserved regulatory mechanism across vertebrates. In addition, srebp1 and srebp2 mRNA respond to replacement of dietary FO with VO. Thus, Atlantic salmon adjust lipid metabolism in response to dietary lipid composition through the transcriptional regulation of gene expression. It may be possible to further increase efficient and effective use of sustainable alternatives to marine products in aquaculture by considering these important molecular interactions when formulating diets., (© 2013.)

Erythronium dens-canis is an early-flowering understory lily of southern Europe with two leaves and a single flower, although a number of plants have only one leaf and do not flower. The leaves are mottled with silvery flecks and brown patches, that gradually vanish turning to a lively green color. The nature and function of this striking variegation pattern were investigated in differently colored leaf parts following the springtime color change. Tissue organization was examined by light and electron microscopy; photosynthetic pigments were analyzed by spectrophotometry and HPLC; chlorophyll fluorescence parameters were evaluated by MINI-PAM. The results showed that brown patches originated in vacuolar anthocyanins in the subepidermal cell layer while air spaces between the upper epidermis and underlying chlorenchyma resulted in silvery flecks. The two leaf areas did not differ in photosynthetic pigments, chloroplast organization and photosynthetic parameters (F(v)/F(m), NPQ, rETR). Greening of brown patches due to anthocyanin resorption was faster in non-flowering plants than in flowering ones, occurring only when young fruits were developing. Anthocyanin disappearance did not change the structural-functional features of photosynthetic tissues. As a whole the results suggest that the anthocyanin pigmentation of E. dens-canis leaves does not affect the photosynthetic light use and has no photoprotective function. It is proposed that the complex leaf color pattern may act as a camouflage to escape herbivores, while the reflective silvery spots may have a role in attracting pollinators of this early-flowering species., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Background & Aims: 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)., Methods: Wistar rats (n = 6/group) received saline, FO, or SO by gavage or saline, FO based-lipid emulsion (FLE), or SO based-lipid emulsion (SLE) iv. The oils were provided at 0.2 g/kg/day for three consecutive days. The animals were sacrificed 24 h after the last administration, blood was collected for plasma, WBC and RBC separation and tissues removed. Fatty acids were analysed by gas chromatography., Results: FO resulted in higher eicosapentaenoic acid (EPA) in plasma PC and liver than the control. FLE resulted in higher EPA, docosahexaenoic acid (DHA) and total n-3 PUFA in plasma PC, WBC and liver than both the control and SLE groups. EPA, DHA and total n-3 PUFA were higher in the heart with FLE compared with SLE. Individual and total n-3 PUFA were higher in plasma PC, WBC, liver and heart with FLE than with FO given by gavage., Conclusion: Short-term iv administration of n-3 PUFA appears to be more effective at increasing EPA and DHA status in plasma, WBC, liver and heart than oral administration. This might be important for rapid treatment with n-3 PUFA., (Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Acute stress induces short-term object recognition memory impairment and elicits endogenous opioid system activation. The aim of this study was thus to evaluate whether opiate system activation mediates the acute stress-induced object recognition memory changes. Adult male Wistar rats were trained in an object recognition task designed to test both short- and long-term memory. Subjects were randomly assigned to receive an intraperitoneal injection of saline, 1 mg/kg naltrexone or 3 mg/kg naltrexone, four and a half hours before the sample trial. Five minutes after the injection, half the subjects were submitted to movement restraint during four hours while the other half remained in their home cages. Non-stressed subjects receiving saline (control) performed adequately during the short-term memory test, while stressed subjects receiving saline displayed impaired performance. Naltrexone prevented such deleterious effect, in spite of the fact that it had no intrinsic effect on short-term object recognition memory. Stressed subjects receiving saline and non-stressed subjects receiving naltrexone performed adequately during the long-term memory test; however, control subjects as well as stressed subjects receiving a high dose of naltrexone performed poorly. Control subjects' dissociated performance during both memory tests suggests that the short-term memory test induced a retroactive interference effect mediated through light opioid system activation; such effect was prevented either by low dose naltrexone administration or by strongly activating the opioid system through acute stress. Both short-term memory retrieval impairment and long-term memory improvement observed in stressed subjects may have been mediated through strong opioid system activation, since they were prevented by high dose naltrexone administration. Therefore, the activation of the opioid system plays a dual modulating role in object recognition memory., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Postural support alters anticipatory postural adjustments (APAs). Efficient adaptation to changes in postural support in reactive and centrally initiated postural synergies is impaired in Parkinson's disease (PD). This study examined whether APAs are affected differently by familiar and novel supports in people with PD, ON and OFF levodopa. The effect of PD and levodopa on the ability to immediately adapt APAs to changes in support and refine with practice was also investigated. Fourteen people with PD and 14 healthy control participants performed 20 single rapid leg lift tasks in four support conditions: unsupported, bilateral handgrip (familiar), bite plate (novel) and a combined handgrip+bite plate condition. APAs, identified from force plate data, were characterized by an increase in the vertical ground reaction force under the lifted leg as a result of a shift of weight toward the stance limb. Results showed the ability to incorporate familiar and novel external supports into the postural strategy was preserved in PD. Controls and PD patients in the OFF state further refined the postural strategy with practice as evidenced by changes in amplitude of vertical ground reaction forces and forces applied to support apparatus within conditions between the initial and final trials. In the ON state, people with PD failed to refine the use of postural supports in any condition. The results suggest that immediate postural adaptation is intact in people with PD and unaffected by levodopa administration but the ability to refine postural adaptations with task experience is compromised by dopamine therapy., (Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.)

Dietary n-3 polyunsaturated fatty acids (PUFA) influence the inductive phase of inflammation but less is known about their effects on the resolution phase. This study examined the effects of dietary fish oil on induction and resolution of antigen-induced inflammation in mice. Mice were fed a control diet with or without 2.8% fish oil, immunized twice with methylated BSA (mBSA) and inflammation induced by intraperitoneal injection of mBSA. Prior to and at different time points after mBSA administration, peritoneal cells were analyzed and expression of surface molecules determined by flow cytometry. Concentration of chemokines, cytokines and soluble cytokine receptors was determined by ELISA. Mice fed the fish oil diet had fewer peritoneal neutrophils, shorter resolution interval and lower levels of pro-inflammatory cytokines and chemokines than mice fed the control diet. In mice fed the fish oil diet there was an early peak in peritoneal levels of the immunosuppressive molecules sIL-6R and TGF-β, that was not seen in mice fed the control diet. In the resolution phase, peritoneal macrophages from mice fed the fish oil diet expressed more of the atypical chemokine receptor D6 and peritoneal TGF-β levels were higher than that in mice fed the control diet. Furthermore, in the late-resolution phase there were more peritoneal eosinophils and macrophages in mice fed the fish oil diet than in mice fed the control diet. These results demonstrate a suppressive effect of n-3 PUFA on the inductive phase of inflammation and indicate an enhancing effect of n-3 PUFA on resolution of inflammation., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Introduction: This intervention examined whether fish-oil-supplementation in late infancy modifies free-play test scores and if this is related to blood pressure (BP) and mean RR interval., Patients and Methods: 83 Danish 9-month-old infants were randomized to ±fish oil (FO) (3.4±1.1mL/d) for 3months and 61 of these completed the free-play-test before and after the intervention., Results: Most of the free-play scores changed during the intervention, but the intervention affected only the number of looks away from the toy, which was increased in +FO and decreased in -FO (p=0.037). The increased numbers of looks away were associated with an increase in erythrocyte eicosapentaenoic acid (r=0.401, p=0.017, n=35) and were also associated with a decrease in systolic-BP (r=-0.511, p<0.001, n=52)., Conclusions: The results indicate that n-3 fatty acid intake also in late infancy can influence brain development and that the cognitive and cardiovascular effects may be related., (© 2013 Elsevier Ltd. All rights reserved.)

Because consumption of processed foods has increased in the last decades and so far its potential influence on emotionality and susceptibility to stress is unknown, we studied the influence of different fatty acids (FA) on behavioral and biochemical parameters after acute restrain stress (AS) exposure. Two sequential generations of female rats were supplemented with soybean oil (control group; C-SO), fish oil (FO) and hydrogenated vegetable fat (HVF) from pregnancy and during lactation. At 41days of age, half the animals of each supplemented group were exposed to AS and observed in open field and elevated plus maze task, followed by euthanasia for biochemical assessments. The HVF-supplemented group showed higher anxiety-like symptoms per se, while the C-SO and FO groups did not show these behaviors. Among groups exposed to AS, HVF showed locomotor restlessness in the open field, while both C-SO and HVF groups showed anxiety-like symptoms in the elevated plus maze, but this was not observed in the FO group. Biochemical evaluations showed higher lipoperoxidation levels and lower cell viability in cortex in the HVF group. In addition, HVF-treated rats showed reduced catalase activity in striatum and hippocampus, as well as increased generation of reactive species in striatum, while FO was associated with increased cell viability in the hippocampus. Among groups exposed to AS, HVF increased reactive species generation in the brain, decreased cell viability in the cortex and striatum, and decreased catalase activity in the striatum and hippocampus. Taken together, our findings show that the type of FA provided during development and growth over two generations is able to modify the brain oxidative status, which was particularly adversely affected by trans fat. In addition, the harmful influence of chronic consumption of trans fats as observed in this study can enhance emotionality and anxiety parameters resulting from stressful situations of everyday life, which can trigger more severe neuropsychiatric conditions., (Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.)

Measurements of enzyme kinetics of renal Na, K-ATPase were used for characterization of ATP- and Na⁺-binding sites in rats that were subjected to 10 days of moderate inflammation that was induced by a single dose of Escherichia coli lipopolysaccharides (LPSs) at a dose of 1 mg kg⁻¹ body weight. We hypothesized that LPSs might initiate a malfunction of renal Na, K-ATPase, which is a key enzyme involved in regulation of sodium homeostasis in the organism. We also investigated the potential effect that fish oil (FO) has in the prevention of Na, K-ATPase alterations by administering FO daily at a dose of 30 mg kg⁻¹. Alone, LPS elevated the level of C-reactive protein by more than 500% and free radicals by 36% in plasma, as indicated by an increased level of malondialdehyde. The Na, K-ATPase was slightly altered in the vicinity of the ATP-binding site as suggested by the 9% increase of the concentration of ATP necessary for half-maximal activation of the enzyme, thus indicating a deteriorated binding of ATP as a consequence of inflammation. Daily supplementation of FO partly attenuated LPS-induced injury, as observed by a significant decrease in the plasma levels of C-reactive protein and free radicals, hence maintaining the activity of renal Na, K-ATPase to the level of healthy control animals. In conclusion, our findings showed that FO prevented an excessive malondialdehyde production in LPS-treated animals and stabilized renal Na, K-ATPase., (© 2013.)

The aim of this study was to investigate the effects of petroselinic acid, found in coriander oil, on the ability of rainbow trout hepatocytes to increase the production of eicosapentaenoic acid (20:5n-3; EPA) and docosahexaenoic acid (22:6n-3; DHA) from [1-(14)C] α-linolenic acid (18:3n-3; ALA) and to reduce the production of arachidonic acid (20:4n-6; ARA) from [1-(14)C] 18:2n-6. Addition of coriander oil increased the production of 22:6n-3, from [1-(14)C] 18:3n-3, at the 0.5 and 1.0% inclusion levels and reduced the conversion of [1-(14)C] 18:2n-6 to 20:4n-6. β-Oxidation was significantly increased at the 1.5% inclusion level for [1-(14)C] 18:2n-6, however β-oxidation for [1-(14)C] 18:3n-3 only showed an increasing trend. Acetate, a main breakdown product of fatty acids (FA) via peroxisomal β-oxidation, decreased three-fold for [1-(14)C] 18:2n-6 and nearly doubled for [1-(14)C] 18:3n-3 when coriander was added at a 1.5% inclusion level. Acyl coenzyme A oxidase (ACO) enzyme activity showed no significant differences between treatments. Relative gene expression of ∆6 desaturase decreased with addition of coriander oil compared to the control. The addition of petroselinic acid via coriander oil to vegetable oil (VO) based diets containing no fishmeal (FM) or fish oil (FO), significantly increased the production of anti-inflammatory precursor 22:6n-3 (P=0.011) and decreased pro-inflammatory precursor 20:4n-6 (P=0.023) in radiolabelled hepatocytes of rainbow trout., (© 2013.)

Long-chain n-3 PUFA (LCPUFA) and palmitate (16:0) positioning in the triacylglycerol (TAG) of infant formula may affect calcium-uptake which could affect bone health. We investigated if a human milk fat substitute (HMFS) with a modified TAG structure holding 16:0 predominantly in the sn-2-position compared with a control (CONT) and if increasing n-3LCPUFA intake giving fish oil (FO) compared with sunflower oil (SO) would affect bone parameters in piglets in two sets of controlled 14d-interventions (n=12/group). We assessed this by dual-energy x-ray absorptiometry, and ex vivo peripheral quantitative computed tomography and mechanical strength. Bone mineral content (BMC) was higher in the FO compared to the SO-group (p=0.03). Despite similar weight gain in HMFS- and CONT-groups, body fat accumulation was higher with HMFS (p<0.001), and BMC, bone area (BA) and cortical BA in femur were lower (p=0.002, p=0.005, and p=0.02, respectively), indicating importance of both n-3LCPUFA and 16:0 TAG-positioning in infant formulas., (© 2013 Elsevier Ltd. All rights reserved.)

The current Western diet often provides considerable amounts of saturated and trans fatty acids (TFA), whose incorporation into neuronal membranes has been implicated in changes of brain neurochemical functions. Such influence has caused concerns due to precipitation of neuropsychiatric disorders, whose data are still unclear. Here we evaluated the influence of different fats on preference parameters for amphetamine (AMPH): adolescent rats were orally supplemented with soybean oil (SO, rich in n-6 FA, which was considered an isocaloric control group), fish oil (FO, rich in n-3 FA) and hydrogenated vegetable fat (HVF, rich in saturated and trans FA) from weaning, which were born of dams supplemented with the same fat from pregnancy and lactation. AMPH preference, anxiety-like symptoms and locomotor index were evaluated in conditioned place preference (CPP), elevated plus maze (EPM) and open-field (OF), respectively, while brain oxidative status was determined in cortex, striatum and hippocampus. HVF increased AMPH-CPP and was associated with withdrawal signs, as observed by increased anxiety-like symptoms. Moreover, SO and FO were not associated with AMPH preference, but only FO-supplemented rats did not show any anxiety-like symptoms or increased locomotion. FO supplementation was related to lower oxidative damages to proteins and increased CAT activity in striatum and hippocampus, as well as increased GSH levels in blood, while HVF was related to increased oxidative status. In conclusion, our study showed the harmful influence of TFA on AMPH-CPP and drug craving symptoms, which can be related to dopaminergic neurotransmission., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The influence of dietary fatty acids (FA) on mania-like behavior and brain oxidative damage were evaluated in rats. First generation of rats born and maintained under supplementation with soybean-oil (SO), fish-oil (FO) or hydrogenated-vegetable-fat (HVF), which are rich in n-6, n-3 and trans (TFA) FA, respectively, until adulthood, were exposed to an amphetamine (AMPH)-induced mania animal model to behavioral and biochemical evaluations. While AMPH caused hyperlocomotion in HVF and, to a less extent, in SO- and FO-groups, a better memory performance was observed in FO group. Among vehicle-groups, HVF increased reactive species (RS) generation and protein-carbonyl (PC) levels in cortex; FO reduced RS generation in hippocampus and decreased PC levels in hippocampus and striatum. Among AMPH-treated animals, HVF exacerbated RS generation in all evaluated brain areas and increased PC levels in cortex and striatum; FO reduced RS generation in hippocampus and decreased PC levels in hippocampus and striatum. FO was related to higher percentage of polyunsaturated fatty acids (PUFA) and docosahexaenoic acid (DHA) in cortex and striatum, while HVF was associated to higher incorporation of TFA in cortex, hippocampus and striatum, besides increased n-6/n-3 FA ratio in striatum. While a continuous exposure to TFA may intensify oxidative events in brain, a prolonged FO consumption may prevent mania-like-behavior; enhance memory besides decreasing brain oxidative markers. A substantial inclusion of processed foods, instead of foods rich in omega-3, in the long term is able to influence the functionality of brain structures related to behavioral disturbances and weaker neuroprotection, whose impact should be considered by food safety authorities and psychiatry experts., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Individuals have different levels of stress sensitivity. An individual's predisposition to experience negative life events (NLEs) may make him/her more vulnerable to a series of psychopathological and physical diseases. However, the neuroanatomical correlates of individual differences in sensitivity to NLEs remain unknown. In this study, voxel-based morphometry was used to identify the gray matter (GM) associations of individual differences in sensitivity to NLEs measured by adolescent self-rating life events checklist. Results showed that there was a positive association between individual NLEs sensitivity and regional GM volume (rGMV) in the ventrolateral prefrontal cortex (VLPFC). GM was mostly evident in the left frontal operculum and a small part of the left middle frontal gyrus. This region was thought to play an important role in introception. Importantly, our study revealed that rumination served as a mediator between the rGMV of the VLPFC and individual NLEs sensitivity. These findings suggest that people with greater VLPFC might be more inclined to ruminate and the ruminative response style might make them more sensitive to NLEs., (Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.)