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Conjugated linoleic acid was detected in rabbit caecotrophs, due to the presence of microbial lipid activity in rabbit cecum. However, the effect of CLA as a functional food in growing rabbit is not well established. Therefore, this study was conducted to determine the effect of CLA on production, meat quality, and its nutrigenomic effect on edible parts of rabbit carcass including skeletal muscle, liver, and adipose tissue. Therefore, seventy five weaned V-Line male rabbits, 30 days old, were randomly allocated into three dietary treatments receiving either basal control diet, diet supplemented with 0.5% (CLAL), or 1% CLA (CLAH). Total experimental period (63 d) was segmented into 7 days adaptation and 56 days experimental period. Dietary supplementation of CLA did not alter growth performance, however, the fat percentage of longissimus lumborum muscle was decreased, with an increase in protein and polyunsaturated fatty acids (PUFA) percentage. Saturated fatty acids (SFA) and mono unsaturated fatty acids (MUFA) were not increased in CLA treated groups. There was tissue specific sensing of CLA, since subcutaneous adipose tissue gene expression of PPARA was downregulated, however, CPT1A tended to be upregulated in liver of CLAL group only (P = 0.09). In skeletal muscle, FASN and PPARG were upregulated in CLAH group only (P ≤0.01). Marked cytoplasmic vacuolation was noticed in liver of CLAH group without altering hepatocyte structure. Adipocyte size was decreased in CLA fed groups, in a dose dependent manner (P <0.01). Cell proliferation determined by PCNA was lower (P <0.01) in adipose tissue of CLA groups. Our data indicate that dietary supplementation of CLA (c9,t11-CLA and t10,c12- CLA) at a dose of 0.5% in growing rabbit diet produce rabbit meat rich in PUFA and lower fat % without altering growth performance and hepatocyte structure. [ABSTRACT FROM AUTHOR]

Background: Despite dietary recommendations of polyunsaturated fatty acids (PUFAs) for cardiometabolic health, n-3 and n-6 PUFAs and their interplay in relation to diabetes risk remain debated. Importantly, data among pregnant women are scarce. We investigated individual plasma phospholipid n-3 and n-6 PUFAs in early to midpregnancy in relation to subsequent risk of gestational diabetes mellitus (GDM).Methods and Findings: Within the National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-Singleton Cohort (n = 2,802), individual plasma phospholipid n-3 and n-6 PUFAs levels were measured at gestational weeks (GWs) 10-14, 15-26, 23-31, and 33-39 among 107 GDM cases (ascertained on average at GW 27) and 214 non-GDM controls. Conditional logistic regression was used, adjusting for major risk factors for GDM. After adjusting for covariates, individual n-3 eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA) were inversely correlated with insulin-resistance markers, whereas individual n-6 dihomo-gamma-linolenic acid (DGLA) was positively correlated with insulin-resistance markers. At GW 15-26, a standard deviation (SD) increase in total n-3 PUFAs and individual n-3 DPA was associated with a 36% (adjusted odds ratio 0.64; 95% CI 0.42-0.96; P = 0.042) and 33% (0.67; 95% CI 0.45-0.99; P = 0.047) lower risk of GDM, respectively; however, the significance did not persist after post hoc false-discovery rate (FDR) correction (FDR-corrected P values > 0.05). Associations between total n-6 PUFAs and GDM were null, whereas associations with individual n-6 PUFAs were differential. Per SD increase, gamma-linolenic acid (GLA) at GWs 10-14 and DGLA at GWs 10-14 and 15-26 were significantly associated with a 1.40- to 1.95-fold higher risk of GDM, whereas docosatetraenoic acid (DTA) at GW 15-26 was associated with a 45% (0.55; 95% CI 0.37-0.83) lower risk of GDM (all FDR-corrected P values < 0.05). Null associations were observed for linoleic acid (LA) in either gestational window in relation to risk of GDM. Women with high (≥median) n-3 PUFAs and low (Conclusions: Our findings may suggest a potential role of primarily endogenously metabolized plasma phospholipid n-6 PUFAs including GLA, DGLA, and DTA in early to midpregnancy in the development of GDM. Null findings on primarily diet-derived n-3 EPA and DHA and n-6 LA do not provide strong evidence to suggest a beneficial role in prevention of GDM, although not excluding the potential benefit of EPA and DHA on glucose-insulin homeostasis given the inverse associations with insulin-resistance markers. Our findings highlight the importance of assessing individual circulating PUFAs to investigate their distinct pathophysiologic roles in glucose homeostasis in pregnancy. [ABSTRACT FROM AUTHOR]

The ecological success of shallow water reef-building corals has been linked to the symbiosis between the coral host and its dinoflagellate symbionts (herein ‘symbionts’). As mixotrophs, symbiotic corals depend on nutrients 1) transferred from their photosynthetic symbionts (autotrophy) and 2) acquired by host feeding on particulate organic resources (heterotrophy). However, coral species differ in the extent to which they depend on heterotrophy for nutrition and these differences are typically poorly defined. Here, a multi-tracer fatty acid approach was used to evaluate the trophic strategies of three species of common reef-building coral (Galaxea fascicularis, Pachyseris speciosa, and Pocillopora verrucosa) whose trophic strategies had previously been identified using carbon stable isotopes. The composition and various indices of fatty acids were compared to examine the relative contribution of symbiont autotrophy and host heterotrophy in coral energy acquisition. A linear discriminant analysis (LDA) was used to estimate the contribution of polyunsaturated fatty acids (PUFA) derived from various potential sources to the coral hosts. The total fatty acid composition and fatty acid indices revealed differences between the more heterotrophic (P. verrucosa) and more autotrophic (P. speciosa) coral hosts, with the coral host G. fascicularis showing overlap with the other two species and greater variability overall. For the more heterotrophic P. verrucosa, the fatty acid indices and LDA results both indicated a greater proportion of copepod-derived fatty acids compared to the other coral species. Overall, the LDA estimated that PUFA derived from particulate resources (e.g., copepods and diatoms) comprised a greater proportion of coral host PUFA in contrast to the lower proportion of symbiont-derived PUFA. These estimates provide insight into the importance of heterotrophy in coral nutrition, especially in productive reef systems. The study supports carbon stable isotope results and demonstrates the utility of fatty acid analyses for exploring the trophic strategies of reef-building corals. [ABSTRACT FROM AUTHOR]

Low temperatures delay aging and promote longevity in many organisms. However, the metabolic and homeostatic aspects of low-temperature–induced longevity remain poorly understood. Here, we show that lipid homeostasis regulated by Caenorhabditis elegans Mediator 15 (MDT-15 or MED15), a transcriptional coregulator, is essential for low-temperature–induced longevity and proteostasis. We find that inhibition of mdt-15 prevents animals from living long at low temperatures. We show that MDT-15 up-regulates fat-7, a fatty acid desaturase that converts saturated fatty acids (SFAs) to unsaturated fatty acids (UFAs), at low temperatures. We then demonstrate that maintaining a high UFA/SFA ratio is essential for proteostasis at low temperatures. We show that dietary supplementation with a monounsaturated fatty acid, oleic acid (OA), substantially mitigates the short life span and proteotoxicity in mdt-15(-) animals at low temperatures. Thus, lipidostasis regulated by MDT-15 appears to be a limiting factor for proteostasis and longevity at low temperatures. Our findings highlight the crucial roles of lipid regulation in maintaining normal organismal physiology under different environmental conditions. [ABSTRACT FROM AUTHOR]

Dinoflagellates from the Symbiodiniaceae family and corals have an ecologically important endosymbiotic relationship. Scleractinian corals cannot survive for long periods without their symbionts. These algae, also known as zooxanthellae, on the other hand, thrives outside the coral cells. The free-living populations of zooxanthellae are essential for the resilience of the coral to environmental stressors such as temperature anomalies and ocean acidification. Yet, little is known about how ocean acidification may affect the free-living zooxanthellae. In this study we aimed to test morphological, physiological and biochemical responses of zooxanthellae from the Symbiodinium genus isolated from the coral Mussismilia braziliensis, endemic to the Brazilian coast, to acidification led by increased atmospheric CO2. We tested whether photosynthetic yield, cell ultrastructure, cell density and lipid profile would change after up to 16 days of exposure to pH 7.5 in an atmospheric pCO2 of 1633 μatm. Photosynthetic yield and cell density were negatively affected and chloroplasts showed vesiculated thylakoids, indicating morphological damage. Moreover, Symbiodinium fatty acid profile drastically changed in acidified condition, showing lower polyunsaturated fatty acids and higher saturated fatty acids contents, when compared to the control, non-acidified condition. These results show that seawater acidification as an only stressor causes significant changes in the physiology, biochemistry and ultrastructure of free-living Symbiodinium. [ABSTRACT FROM AUTHOR]

Progression of prostate cancer to lethal forms is marked by emergence of hormone-independent proliferation of the cancer cells. Nutritional and epidemiological studies have indicated that prostate cancer progression is correlated with the consumption of polyunsaturated fatty acids (PUFA). To shed additional light on the cell-level mechanisms of the observed correlation, we compared the sensitivity of hormone-dependent and hormone-independent prostate cancer cells to growth medium supplementation with free PUFAs in a cell proliferation and viability assay. Our data show that the hormone-dependent cells are comparatively insensitive to various PUFAs, at the same time as the growth and viability of hormone-independent cells lines are strongly inhibited by most of the tested PUFAs, whether n–3 or n–6. We speculate that this difference may be at least partially responsible for the observed effects of specific dietary lipids in prostate cancer. The new data strengthen the case for dietary intervention as part of potential new therapeutic strategies seeking to impede prostate cancer progression. [ABSTRACT FROM AUTHOR]

Accumulation of amyloid ß (Aß) peptides, the major component of amyloid fibrils in senile plaques, is one of the main causes of Alzheimer’s disease. Docosahexaenoic acid (DHA) is a fatty acid abundant in the brain, and is reported to have protective effects against Alzheimer’s disease, although the mechanistic effects of DHA against Alzheimer’s pathophysiology remain unclear. Because dietary supplementation of DHA in Aß precursor protein transgenic mice ameliorates Aß pathology and behavioral deficits, we hypothesize that DHA may affect the fibrillization and deposition of Aß. Here we studied the effect of different types of fatty acids on Aß fibril formation by in vitro Aß fibrillization assay. Formation of amyloid fibrils consists of two steps, i.e., the initial nucleation phase and the following elongation phase. We found that unsaturated fatty acids, especially DHA, accelerated the formation of Aß fibrils with a unique short and curved morphology in its nucleation phase, which did not elongate further into the long and straight, mature Aß fibrils. Addition of DHA afterwards did not modify the morphology of the mature Aß(1–40) fibrils. The short and curved Aß fibrils formed in the presence of DHA did not facilitate the elongation phase of Aß fibril formation, suggesting that DHA promotes the formation of “off-pathway” conformers of Aß. Our study unravels a possible mechanism of how DHA acts protectively against the pathophysiology of Alzheimer’s disease. [ABSTRACT FROM AUTHOR]

The Chinese mitten crab (Eriocheir sinensis) is an euryhaline crustacean, whose adults migrate downstream to estuaries for reproduction. Lipids are believed to be involved in salinity adaptation during migration. This study investigated the effects of different salinities (0, 6, 12, and 18‰) on the total lipids, neutral lipids, and polar lipids contents, and fatty acid profiles in the gonads, hepatopancreas, and muscles of adult E. sinensis after 40 days of salinity adaptation. The results showed that the males and females from 12‰ treatment had the highest contents of total lipids and neutral lipids in their hepatopancreas and total lipids in the muscles. Notably, salinity had a greater effect on the fatty acid profiles in the hepatopancreas compared to that in the gonads and muscles. The male hepatopancreas treated with 18‰ salinity had the highest percentage of total n-6 polyunsaturated fatty acid (∑n-6PUFA) in both neutral lipids and polar lipids, while the percentage of total n-3 polyunsaturated fatty acid (∑n-3PUFA) in neutral lipids and polar lipids decreased significantly with increasing salinity in males. In females, the 0‰ treatment had the highest percentages of total saturated fatty acids in neutral lipids and polar lipids in the hepatopancreas, while the highest ∑n-3PUFA and ∑n-6PUFA in neutral lipids and polar lipids were detected in the 12‰ treatment group. In conclusion, brackish water could promote the accumulations of total lipids and neutral lipids in the hepatopancreas and change the fatty acid profiles of adult E. sinensis, particularly in the hepatopancreas after long-term salinity adaptation. [ABSTRACT FROM AUTHOR]

Oxylipins are metabolites with a variety of biological functions. However, the biosynthetic pathway is widely unknown. It is considered that the first step is the oxygenation of polyunsaturated fatty acids like linoleic acid. Therefore, a lipoxygenase (LOX) from the edible basidiomycete Agrocybe aegerita was investigated. The AaeLOX4 was heterologously expressed in E. coli and purified via affinity chromatography and gel filtration. Biochemical properties and kinetic parameters of the purified AaeLOX4 were determined with linoleic acid and linolenic acid as substrates. The obtained Km, vmax and kcat values for linoleic acid were 295.5 μM, 16.5 μM · min-1 · mg-1 and 103.9 s-1, respectively. For linolenic acid Km, vmax and kcat values of 634.2 μM, 19.5 μM · min-1 · mg-1 and 18.3 s-1 were calculated. Maximum activities were observed at pH 7.5 and 25 °C. The main product of linoleic acid conversion was identified with normal-phase HPLC. This analysis revealed an explicit production of 13-hydroperoxy-9,11-octadecadienoic acid (13-HPOD). The experimental regio specificity is underpinned by the amino acid residues W384, F450, R594 and V635 considered relevant for regio specificity in LOX. In conclusion, HPLC-analysis and alignments revealed that AaeLOX4 is a 13-LOX. [ABSTRACT FROM AUTHOR]

In the present two-year study, an attempt was made to estimate the grain yield, grain nutrient uptake, and oil quality of three commonly grown maize (Zea mays L.) hybrids fertilized with varied levels of nitrogen (N), phosphorus (P) and potassium (K). Results obtained from both the experimental years indicated that application of 125% of recommended dose of fertilizer (RDF) recorded maximum grain yield (10.37 t ha-1; 124% higher than control). When compared with 100% RDF, grain yield reduction with nutrient omission was 44% for N omission, 17% for P omission, and 27% for K omission. Nitrogen uptake was increased with increasing NPK levels up to 150% RDF that was statistically at par (p ≥ 0.01) with 125% RDF. Increasing trend in P and K uptake was observed with successive increase in NPK levels up to 125% RDF, above which it declined. The protein content was significantly higher in grains of var. P 3396 with 125% RDF. Nutrient management has significant (p ≤ 0.01) role in the grain oil content. Saturated fatty acids (palmitic, stearic and arachidic acid) content decreased, and unsaturated fatty acid (oleic, linoleic and linolenic acid) increased with increasing NPK levels. The average oleic acid desaturation and linoleic acid desaturation ratios were increased with increasing NPK levels up to 100 and 125% RDF, respectively. However, average monounsaturated fatty acids (MUFA): poly-unsaturated fatty acids (PUFA), saturated: unsaturated as well as linoleic: linolenic acid ratios were increased on receiving 75% RDF, and beyond that it showed decreasing trend. The omission of K had the highest inhibitory effect on corn oil quality followed by N and P omission. [ABSTRACT FROM AUTHOR]

Starvation is among the most ancient of selection pressures, driving evolution of a robust arsenal of starvation survival defenses. In order to survive starvation stress, organisms must be able to curtail anabolic processes during starvation and judiciously activate catabolic pathways. Although the activation of metabolic defenses in response to nutrient deprivation is an obvious component of starvation survival, less appreciated is the importance of the ability to recover from starvation upon re-exposure to nutrients. In order for organisms to successfully recover from starvation, cells must be kept in a state of ready so that upon the return of nutrients, activities such as growth and reproduction can be resumed. Critical to this state of ready is the lysosome, an organelle that provides essential signals of nutrient sufficiency to cell growth-activating pathways in the fed state. In this issue, Murphy and colleagues provide evidence that exposure of Caenorhabditis elegans roundworms to 2 simple nutrients, glucose and the polyunsaturated fatty acid linoleate, is able to render lysosomal function competent to activate key downstream starvation recovery pathways, bypassing the need for a master transcriptional regulator of lysosomes. These findings provide a quantum leap forward in our understanding of the cellular determinants that permit organisms to survive cycles of feast and famine. [ABSTRACT FROM AUTHOR]

Phytoplankton are the oceans’ principal source of polyunsaturated fatty acids that support the growth and reproduction of consumers such as copepods. Previous studies have demonstrated ocean acidification (OA) can change the availability of polyunsaturated fatty acids to consumer diets which may affect consumer reproduction. Two laboratory experiments were conducted to examine the effects of feeding high-pCO2-reared phytoplankton on copepod egg production, hatching success, and naupliar survival. Marine phytoplankton Rhodomonas salina, Skeletonema marinoi, Prorocentrum micans, and Isochrysis galbana were exponentially grown in semi-continuous cultures at present (control) (400 ppm CO2, pH~8.1) and future (1,000 ppm CO2, pH~7.8) conditions and provided to Acartia tonsa copepods over 4 consecutive days as either nitrogen-limited (Exp. I) or nitrogen-depleted (Exp. II) mixed assemblage of phytoplankton. The composition of FAs in the phytoplankton diet was affected by pCO2 concentration and nitrogen deficiency; the ratio of essential fatty acids to total polyunsaturated fatty acids decreased in phytoplankton grown under high pCO2 and the mass of total fatty acids increased under nitrogen depletion. Additionally, total concentrations of essential fatty acids and polyunsaturated fatty acids in the diet mixtures were less under the high-pCO2 compared to the control-pCO2 treatments. Median egg production, hatching success, and naupliar survival were 48–52%, 4–87%, and 9–100% lower, respectively, in females fed high-pCO2 than females fed low-pCO2 phytoplankton, but this decrease in reproductive success was less severe when fed N-depleted, but fatty acid-rich cells. This study demonstrates that the effects of OA on the nutritional quality of phytoplankton (i.e., their cellular fatty acid composition and quota) were modified by the level of nitrogen deficiency and the resulting negative reproductive response of marine primary consumers. [ABSTRACT FROM AUTHOR]

The reliance of the aquafeed industry on marine resources has to be reduced by innovative approaches in fish nutrition. Thus, a three-factorial approach (fish oil reduced diet, phytochemical genistein, and temperature reduction) was chosen to investigate the interaction of effects on growth performance and tissue omega-3 long chain polyunsaturated fatty acid (LC-PUFA) levels in juvenile sea bream (Sparus aurata, 12.5 ± 2.2 g). Genistein is a phytoestrogen with estrogen-like activity and thus LC-PUFA increasing potential. A decrease in the rearing temperature was chosen based on the positive effects of low temperature on fish lipid quality. The experimental diets were reduced in marine ingredients and had a fish oil content of either 6% dry matter (DM; F6: positive control) or 2% DM (F2: negative control) and were administered in the plain variant or with inclusion of 0.15% DM genistein (F6 + G and F2 + G). The feeding trial was performed simultaneously at 23°C and 19°C. The results indicated that solely temperature had a significant effect on growth performance and whole body nutrient composition of sea bream. Nevertheless, the interaction of all three factors significantly affected the fatty acid compositions of liver and fillet tissue. Most importantly, they led to a significant increase by 4.3% of fillet LC-PUFA content in sea bream fed with the diet F6 + G in comparison to control fish fed diet F6, when both groups were held at 19°C. It is hypothesized that genistein can act via estrogen-like as well as other mechanisms and that the dietary LC-PUFA content may impact its mode of action. Temperature most likely exhibited its effects indirectly via altered growth rates and metabolism. Although effects of all three factors and of genistein in particular were only marginal, they highlight a possibility to utilize the genetic capacity of sea bream to improve tissue lipid quality. [ABSTRACT FROM AUTHOR]

Camellia oleifera Abel (C. oleifera) absorb nutrients from surrounding soils and its yield is highly influenced by these nutrients and by fertilizer application. Thus, the soil nutrients play a central role in C. oleifera production. This study investigated the effects of biogas slurry applications on soil nutrients and economic traits of C. oleifera fruits. Five different amounts of biogas slurry (0, 10, 20, 30, or 40 kg/plant/year, three applications per year) were used as fertilizer for C. oleifera plants in 2015 and 2016. The nutrients of rhizosphere soil and the economic traits, including fruit yield, seed rate, and oil yield of C. oleifera fruit, were measured each year. The results showed that fertilization with biogas slurry significantly increased soil organic matter, available nitrogen (N), phosphorus (P), and potassium (K) both in 2015 and 2016. Increases in soil available N, P, and K were maximal in the highest slurry application group followed by the second highest application group. The oil yield correlated with the content of soil available P in both 2015 and 2016, and with soil organic matter in 2015. Fertilization with biogas slurry decreased the saturated fatty acid content in fruit but had no effect on the unsaturated fatty acid content. In conclusion, fertilization with biogas slurry increased rhizosphere soil nutrients and fruit economic traits of C. oleifera and rates of at least30 kg/plant/year had the most positive effects. This study expands the knowledge of fertilization with biogas slurry in C. oleifera production. [ABSTRACT FROM AUTHOR]

Phytogenic additives such as thymol are encountering growing interest in the poultry industry. However, there are still questions concerning dynamics of their bioavailability, biological action, optimal dosage and duration of supplementation needed to achieve meaningful effects, as well as persistence of induced changes after supplement withdrawal. We studied the link between the dynamics of free thymol concentration and the changes in fatty acids composition in quail egg yolk, both during a month-long chronic dietary supplementation and after 3 weeks of supplement withdrawal (post-supplementation). Fifty, 85 days-old, female quail of homogeneous body weights (251±1g) in egg-laying peak were used. To evaluate potential dose-dependent effects, three increasing doses 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) and two controls were evaluated (n = 10). In parallel, we assessed the concomitant changes in free thymol excretion, potential liver histopathological changes, and birds´ performance traits. Egg yolk and droppings show a dose-dependent increase in THY concentration after 9 days of supplementation and a decrease after post-supplementation. In egg yolk, these changes were accompanied by reduced saturated fatty acid concentrations achieved by 28 days of supplementation in THY2 and 14 days of supplementation in THY4 and THY6. However, after post-supplementation the aforementioned effect disappeared in THY2 but not in THY4 and THY6. While THY2 failed to increase polyunsaturated fatty acids, THY4 and THY6 increased polyunsaturated fatty acids by day 14 of supplementation and remained increased after post-supplementation. Fatty acids changes induced by thymol are consistent with improved nutritional quality of eggs. No treatment effects were observed in liver histopathology and female performance. Findings suggest that both dose of thymol and duration of supplementation modulate thymol and fatty acids concentrations in egg yolk and thymol concentration in droppings. Furthermore, the persistence of those effects after post-supplementation period is also a dose-dependent phenomenon. [ABSTRACT FROM AUTHOR]

Fatty acids, as key components of cellular membranes and complex lipids, may play a central role in endocrine signalling and the function of adipose tissue and liver. Thus, the lipid fatty acid composition may play a role in health status in the equine. This study aimed to investigate the fatty acid composition of different tissues and liver lipid classes by comparing Warmblood horses and Shetland ponies under defined conditions. We hypothesized that ponies show different lipid patterns than horses in adipose tissue, liver and plasma. Six Warmblood horses and six Shetland ponies were housed and fed under identical conditions. Tissue and blood sampling were performed following a standardized protocol. A one-step lipid extraction, methylation and trans-esterification method with subsequent gas chromatography was used to analyse the total lipid content and fatty acid profile of retroperitoneal, mesocolon and subcutaneous adipose tissue, liver and plasma. Fatty acids were grouped according to their degree of saturation and their conjugated double bond into the respective lipid classes. In the adipose tissues, saturated fatty acids (SFAs) and n-9 monounsaturated fatty acids (n-9 MUFAs) were most present in ponies and horses. N-6 polyunsaturated fatty acids (n-6 PUFAs), followed by SFAs, were most frequently found in liver tissue and plasma in all animals. Horses, in comparison to ponies, had significantly higher n-6 PUFA levels in all tissues and plasma. In liver tissue, horses had significantly lower hepatic iso-branched-chain fatty acids (iso-BCFAs) than ponies. The hepatic fatty acid composition of selected lipid classes was different between horses and ponies. In the polar PL fraction, horses had low n-9 MUFA and n-3 PUFA contents but higher n-6 PUFA contents than ponies. Furthermore, iso-BCFAs are absent in several hepatic lipid fractions of horses but not ponies. The differences in fatty acid lipid classes between horses and ponies provide key information on the species- and location-specific regulation of FA metabolism, thus affecting health status such as inflammatory responses. [ABSTRACT FROM AUTHOR]

During pond culture of Eriocheir sinensis, a high limb-impairment rate restricts the industry development and quality. Therefore, research on limb autotomy and regeneration has important practical significance for the industrial development and basic biology of E. sinensis. This study evaluated the changes in bud morphology, growth-related gene expression and nutritional status during cheliped regeneration in E. sinensis. The study found that the new cheliped was pre-formed in the bud and then regenerated with the completion of molting of E. sinensis. The new cheliped was similar in morphology to the normal cheliped after the first molting but smaller in size. The qRT-PCR results of growth-related genes showed that the expression levels of EcR-mRNA (ecdysteroid receptor) and Chi-mRNA (chitinase) were significantly up-regulated, whereas the expression of MIH-mRNA (molt-inhibiting hormone) was significantly down-regulated (P < 0.05). The nutritional status during the regeneration process showed that the hepatopancreas total lipid content decreased significantly within 28 days and was significantly lower in the autotomy group than in the control group at 14 d and 21 d (P < 0.05). The hepatopancreas fatty acid composition results showed that saturated fatty acids (SFA), highly unsaturated fatty acids (HUFA) and n-3/n-6 were significantly higher in the autotomy group than in the control group at 21 d (P < 0.05), whereas the ∑ n-6 PUFA and ∑ n-3 PUFA at 1 d and 7 d, and the monounsaturated fatty acid (MUFA) at 28 d in the autotomy group were significantly lower than in the control group (P < 0.05). Moreover, the levels of eicosatetraenoic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) showed that DHA was significantly lower at 7 d and significantly higher at 21 d in the autotomy group than in the control group (P < 0.05), whereas ARA and EPA were not significantly different between the two groups. Muscle L-tryptophan content was significantly lower at 1 d and significantly higher at 7 d in the autotomy group than in the control group (P < 0.05). These results indicate that during the cheliped regeneration process, crabs could accelerate molting and regeneration by regulating growth-related gene expression (e.g., EcR-mRNA and MIH-mRNA) and nutrient metabolism (e.g., lipid metabolism). [ABSTRACT FROM AUTHOR]

Aurantiochytrium limacinum has received attention because of its abundance of polyunsaturated fatty acids (PUFAs), particularly docosahexaenoic acid (DHA). DHA is synthesized through the polyketide synthase (PKS) pathway in A. limacinum. The related enzymes of the PKS pathway are mainly expressed by three gene clusters, called pks1, pks2 and pks3. In this study, the full-length pks3 gene was obtained by polymerase chain reaction amplification and Genome Walking technology. Based on a domain analysis of the deduced amino acid sequence of the pks3 gene, 3-ketoacyl-ACP reductase (KR) and dehydratase (DH) enzyme domains were identified. Herein, A. limacinum OUC168 was engineered by gene knock-in of KR and DH using the 18S rDNA sequence as the homologous recombination site. Total fatty acid contents and the degree of unsaturation of total fatty acids increased after the kr or dh gene was knocked in. The cloning and functional study of the pks3 gene of A. limacinum establishes a foundation for revealing the DHA synthetic pathway. Gene knock-in of the enzyme domain associated with PKS synthesis has the potential to provide effective recombinant strains with higher DHA content for industrial applications. [ABSTRACT FROM AUTHOR]

We have created a new, fast-growing strain of common carp with higher unsaturated fatty acid content in muscle. To better understand the impacts of gene regulation in intestinal tissue on growth and unsaturated fatty acid content, we conducted a comparative RNA-Seq transcriptome analysis between intestine samples of Selected and Control groups (and corroborated selected results by PCR). After eight weeks of cage culture, weight gain of the Selected group was 20.84% higher. In muscles of the control group, monounsaturated fatty acids (FAs) were more abundant, whereas polyunsaturated FAs were more abundant in muscles of the Selected group. In total, we found 106 differentially expressed genes (DEGs) between the two groups. Only the endocytosis pathway was significantly enriched in DEGs, with two upregulated genes: il2rb and ehd1. The latter is involved in the growth hormone/insulin-like growth factor (Gh/Igf) axis, which plays a key role in the regulation of growth in animals. tll2, which is known to be associated with intestinal regeneration, was extremely highly upregulated in both transcriptomic (infinite) and qPCR (610.70) analyses. Two of the upregulated genes are associated with the fatty acid metabolism, several genes are likely to be indicators of heightened transcription levels, several are associated with metabolic and developmental roles, several with neuronal functions (including two with vision), several with the immune system, and two downregulated genes with the development of vasculature. The higher growth rate of the Selected group is likely to be at least partially attributed to increased endocytosis efficiency and genetically-driven behavioural differences (higher aggression levels). There are some indications that this new strain might have slightly impaired immune responses, and a higher propensity for inherited diseases leading to sight impairment, as well for neurodegenerative diseases in general, but these indications still need to be confirmed. [ABSTRACT FROM AUTHOR]

The increasing use of terrestrial plant lipids to replace of fish oil in commercial aquafeeds requires understanding synthesis and storage of long chain-polyunsaturated fatty acids (LC-PUFA) in farmed fish. Manipulation of dietary fatty acids may maximize tissue storage of LC-PUFA, through increased production and selective utilization. A data synthesis study was conducted to estimate optimal levels of fatty acids that may maximize the production and storage of LC-PUFA in the edible portion of salmonids. Data were compiled from four studies with Atlantic salmon, rainbow trout, and steelhead trout (total n = 180) which were fed diets containing different terrestrial-based oils to replace fish oil. LC-PUFA (%) were linearly correlated between diet and muscle tissue (p < 0.001; r2 > 44%), indicating proportional storage after consumption. The slope, or retention rate, was highest for docosahexaenoic acid (DHA) at 1.23, indicating that an additional 23% of DHA was stored in the muscle. Dietary saturated fatty acids were positively related to DHA stored in the muscle (p < 0.001; r2 = 22%), which may involve membrane structural requirements, as well as selective catabolism. DHA was found to be optimally stored with a dietary n-3: n-6 ratio of 1.03: 1. These new results provide a baseline of optimal dietary ratios that can be tested experimentally to determine the efficacy of balancing dietary fatty acids for maximum LC-PUFA storage. [ABSTRACT FROM AUTHOR]

Alcoholic liver disease (ALD), a significant health problem, progresses through the course of several pathologies including steatosis, steatohepatitis, fibrosis, and cirrhosis. There are no effective FDA-approved medications to prevent or treat any stages of ALD, and the mechanisms involved in ALD pathogenesis are not well understood. Bioactive lipid metabolites play a crucial role in numerous pathological conditions, as well as in the induction and resolution of inflammation. Herein, a hepatic lipidomic analysis was performed on a mouse model of ALD with the objective of identifying novel metabolic pathways and lipid mediators associated with alcoholic steatohepatitis, which might be potential novel biomarkers and therapeutic targets for the disease. We found that ethanol and dietary unsaturated, but not saturated, fat caused elevated plasma ALT levels, hepatic steatosis and inflammation. These pathologies were associated with increased levels of bioactive lipid metabolites generally involved in pro-inflammatory responses, including 13-hydroxy-octadecadienoic acid, 9,10- and 12,13-dihydroxy-octadecenoic acids, 5-, 8-, 9-, 11-, 15-hydroxy-eicosatetraenoic acids, and 8,9- and 11,12-dihydroxy-eicosatrienoic acids, in parallel with an increase in pro-resolving mediators, such as lipoxin A4, 18-hydroxy-eicosapentaenoic acid, and 10S,17S-dihydroxy-docosahexaenoic acid. Elucidation of alterations in these lipid metabolites may shed new light into the molecular mechanisms underlying ALD development/progression, and be potential novel therapeutic targets. [ABSTRACT FROM AUTHOR]

Positive strand RNA viruses, such as dengue virus type 2 (DENV2) expand and structurally alter ER membranes to optimize cellular communication pathways that promote viral replicative needs. These complex rearrangements require significant protein scaffolding as well as changes to the ER chemical composition to support these structures. We have previously shown that the lipid abundance and repertoire of host cells are significantly altered during infection with these viruses. Specifically, enzymes in the lipid biosynthesis pathway such as fatty acid synthase (FAS) are recruited to viral replication sites by interaction with viral proteins and displayed enhanced activities during infection. We have now identified that events downstream of FAS (fatty acid desaturation) are critical for virus replication. In this study we screened enzymes in the unsaturated fatty acid (UFA) biosynthetic pathway and found that the rate-limiting enzyme in monounsaturated fatty acid biosynthesis, stearoyl-CoA desaturase 1 (SCD1), is indispensable for DENV2 replication. The enzymatic activity of SCD1, was required for viral genome replication and particle release, and it was regulated in a time-dependent manner with a stringent requirement early during viral infection. As infection progressed, SCD1 protein expression levels were inversely correlated with the concentration of viral dsRNA in the cell. This modulation of SCD1, coinciding with the stage of viral replication, highlighted its function as a trigger of early infection and an enzyme that controlled alternate lipid requirements during early versus advanced infections. Loss of function of this enzyme disrupted structural alterations of assembled viral particles rendering them non-infectious and immature and defective in viral entry. This study identifies the complex involvement of SCD1 in DENV2 infection and demonstrates that these viruses alter ER lipid composition to increase infectivity of the virus particles. [ABSTRACT FROM AUTHOR]

Unsaturated omega-3 fatty acids, especially docosahexaenoic acid (DHA), when fed to dogs improves cognitive and neurological development. Supplementation with omega-3 fatty acids such as DHA and eicosapentaenoic acid (EPA) has also been associated with lipid peroxidation, which in turn has been implicated in reduced body weight and altered bone formation. To assess the impact of omega-3 fatty acid supplementation on skeletal growth, diets containing three levels of DHA and EPA (0.01 and 0.01%, 0.14 and 0.12%, and 0.21 and 0.18%, respectively) were fed to bitches during gestation and lactation with puppies also supplemented through weaning. Thus, the subjects studied were the puppies supplemented with DHA and EPA through gestation and early postnatal life. The hip joint conformation of the puppies (n = 676) was recorded at adulthood using two radiographic, non-invasive evaluations. In this population, females had higher hip distraction indices (DI) than males. Males from the lower two levels of DHA and EPA supplementation had significantly smaller hip DI than all females and males from the highest DHA and EPA supplementation. In contrast, there were no diet effects on anatomical indicators of hip joint conformation and no visible arthritic changes. These data suggest that dietary supplementation of DHA and EPA during gestation and the perinatal period to weaning does not adversely influence hip joint formation of dogs. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the effects of altering the ratio of n-6 to n-3 fatty acids in the diet on meat quality, fatty acid composition of muscle, and expression of lipogenic genes in the muscle of Boer goats. A total of twenty-one Boer goats (5 months old; 31.66±1.07 kg body weight) were randomly assigned to three dietary treatments with n-6:n-3 fatty acid ratios of 2.27:1 (LR), 5.01:1 (MR) and 10.38:1 (HR), fed at 3.7% of body weight. After 100 days of feeding, all goats were slaughtered and the longissimus dorsi muscle was sampled for analysis of fatty acids and gene expression. The dietary treatments did not affect (P>0.05) the carcass traits, and meat quality of growing goats. The concentrations of cis-9,trans-11 conjugated linoleic acid, trans vaccenic acid, polyunsaturated fatty acids, and unsaturated/saturated fatty acid ratios linearly increased (P<0.01) with decreasing dietary n-6:n-3 fatty acid ratios, especially for LR in the longissimus dorsi muscle of goats. In contrast, the mRNA expression level of the PPARα and PPARγ was down-regulated and stearoyl-CoA desaturase up-regulated in the longissimus dorsi of growing goats with increasing dietary n-6:n-3 fatty acid ratios (P<0.01). In conclusion, the results obtained indicate that the optimal n-6:n-3 fatty acid ratio of 2.27:1 exerted beneficial effects on meat fatty acid profiles, leading towards an enrichment in n-3 polyunsaturated fatty acids and conjugated linoleic acid in goat intramuscular fat. [ABSTRACT FROM AUTHOR]

Introduction: Pharmacological defatting of rat hepatocytes and hepatoma cell lines suggests that the same method could be used to ameliorate macrovesicular steatosis in moderate to severely fatty livers. However there is no data assessing the effects of those drugs on primary human liver cells. We aimed to determine the effectiveness of a pharmacological cocktail in reducing the in vitro lipid content of primary human hepatocytes (PHH). In addition we sought to determine the cytotoxicity of the cocktail towards non-parenchymal liver cells. Methods: Steatosis was induced in PHH by supplementation with a combination of saturated and unsaturated free fatty acids. This was followed by addition of a defatting drug cocktail for up to 48 hours. The same experimental method was used with human intra-hepatic endothelial cells (HIEC) and human cholangiocytes. MTT assay was used to assess cell viability, triglyceride quantification and oil red O staining were used to determine intracellular lipids content whilst ketone bodies were measured in the supernatants following experimentation. Results: Incubation of fat loaded PHH with the drugs over 48 hours reduced the intracellular lipid area by 54%, from 12.85% to 5.99% (p = 0.002) (percentage of total oil red O area), and intracellular triglyceride by 35%, from 28.24 to 18.30 nmol/million of cells (p<0.001). Total supernatant ketone bodies increased 1.4-fold over 48 hours in the defatted PHH compared with vehicle controls (p = 0.002). Moreover incubation with the drugs for 48 hours increased the viability of PHH by 11%, cholangiocytes by 25% whilst having no cytotoxic effects on HIEC. Conclusion: These data demonstrate that pharmacological intervention can significantly decrease intracellular lipid content of PHH, increase fatty acids β-oxidation whilst being non-toxic to PHH, HIEC or cholangiocytes. [ABSTRACT FROM AUTHOR]

The fatty acid composition of the diet has been linked to the prevalence of diabetes and cardiovascular diseases. Compared with monounsaturated fatty acids, saturated fatty acids decrease fat oxidation and diet-induced thermogenesis. A potential limitation of previous studies was the short duration (≦5h) of calorimetry used. The present study compared the effects of a meal rich in saturated and unsaturated fatty acids on 24-h of fat oxidation. Ten males participated in two sessions of indirect calorimetry in a whole-room metabolic chamber. At each session, subjects consumed three meals rich in palm oil (44.3% as saturated, 42.3% as monounsaturated and 13.4% as polyunsaturated fatty acid) or rapeseed oil (11.7% as saturated, 59.3% as monounsaturated and 29.0% as polyunsaturated fatty acid). Fat oxidation over 24-h was significantly higher in the meal rich in rapeseed oil (779 ± 202 kcal/day) than that rich in palm oil (703 ± 158 kcal/day, P < 0.05), although energy expenditure was similar between both meal conditions. Meal rich in unsaturated fatty acids increased the oxidation of exogenous and/or endogenous fat. The results of a long calorimetry period indicate that rapeseed oil offered an advantage toward increased 24-h fat oxidation in healthy young males. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and its incidence is increasing worldwide. One method used to restore sinus rhythm is direct current cardioversion (DCCV). Despite the high success rate of DCCV, AF typically recurs within the first 2 weeks. However, our understanding of the pathophysiology of AF recurrence, incidence, and progression are highly limited. Lipidomic profiling was applied to identify altered lipids in plasma from patients with AF using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multivariate statistical analysis. Partial least-squares discriminant analysis revealed a clear separation between AF patients and healthy controls. The levels of several lipid species, including fatty acids and phospholipids, were different between AF patients and healthy controls, indicating that oxidative stress and inflammation are associated with the pathogenesis of AF. Similar patterns were also detected between recurrent and non-recurrent AF patients. These results suggest that the elevated saturated fatty acid and reduced polyunsaturated fatty acid levels in AF patients may be associated with enhanced inflammation and that free fatty acid levels may play a crucial role in the development and progression of AF. [ABSTRACT FROM AUTHOR]

Pecan is an economically important nut crop tree due to its unique texture and flavor properties. The pecan seed is rich of unsaturated fatty acid and protein. However, little is known about the molecular mechanisms of the biosynthesis of fatty acids in the developing seeds. In this study, transcriptome sequencing of the developing seeds was performed using Illumina sequencing technology. Pecan seed embryos at different developmental stages were collected and sequenced. The transcriptomes of pecan seeds at two key developing stages (PA, the initial stage and PS, the fast oil accumulation stage) were also compared. A total of 82,155 unigenes, with an average length of 1,198 bp from seven independent libraries were generated. After functional annotations, we detected approximately 55,854 CDS, among which, 2,807 were Transcription Factor (TF) coding unigenes. Further, there were 13,325 unigenes that showed a 2-fold or greater expression difference between the two groups of libraries (two developmental stages). After transcriptome analysis, we identified abundant unigenes that could be involved in fatty acid biosynthesis, degradation and some other aspects of seed development in pecan. This study presents a comprehensive dataset of transcriptomic changes during the seed development of pecan. It provides insights in understanding the molecular mechanisms responsible for fatty acid biosynthesis in the seed development. The identification of functional genes will also be useful for the molecular breeding work of pecan. [ABSTRACT FROM AUTHOR]

Fatty acids metabolic products determine meat quality in chickens. Identifying genes associated with fatty acids composition could provide valuable information for the complex genetic networks of genes with underlying variations in fatty acids synthesis. RNA sequencing (RNA-Seq) was conducted to explore the chicken transcriptome from the thigh muscle tissue of 6 Huangshan Black Chickens with 3 extremely high and low phenotypic values for percentage of polyunsaturated fatty acids (PUFAs). In total, we obtained 41,139,108–44,901,729 uniquely mapped reads, which covered 74.15% of the current annotated transcripts including 18964 mRNA transcripts, across all the six thigh muscle tissue samples. Of these, we revealed 274 differentially expressed genes (DEGs) with a highly significant correlation with polyunsaturated fatty acids percentage between the comparison groups based on the ratio of PUFA/SFA. Gene ontology and pathway analysis indicated that the DEGs were enriched in particular biological processes affecting fatty acids metabolism, biosynthesis of unsaturated fatty acids (USFAs), and cell junction-related pathways. Integrated interpretation of differential gene expression and formerly reported quantitative trait loci (QTL) demonstrated that FADS2, DCN, FRZB, OGN, PRKAG3, LHFP, CHCHD10, CYTL1, FBLN5, and ADGRD1 are the most promising candidate genes affecting polyunsaturated fatty acids percentage. [ABSTRACT FROM AUTHOR]

The increasing incidence of diabetes mellitus is becoming a serious threat to human health in various parts of the world. Studies with dairy products have shown a potential beneficial effect against diabetes. This experiment evaluated the supplementation of milk naturally enriched with polyunsaturated fatty acids (PUFA) and polyphenols in rats with streptozotocin-induced diabetes. Forty male 28-day-old Wistar rats were distributed in four experimental treatments of diabetic animals (streptozotocin induction) and a normal group (non-induced). Experimental treatments were: control (water), whole common milk (COM-M), milk enriched with PUFA (PUFA-M), milk enriched with PUFA and polyphenols (PUFA/P-M) through a special diet offered to dairy cows. Milk supplementation at a dose 5 mL/kg body weight was performed for 77 days, 42 days before and 35 days after diabetes induction. The COM-M supplementation increased brown fat deposits, reduced post-induction glucose levels, reduced blood fructosamine levels, and improved glucose tolerance. Milk enriched with PUFA reduced final fasting glucose, LDL levels, and improved blood antioxidant capacity. Milk enriched with PUFA and polyphenols promoted an increase in gastrocnemius muscle mass, and a reduction in mesenteric fat and LDL levels. Milk intake, with an emphasis on milk enriched with PUFA and polyphenols, attenuated the metabolic disorders of streptozotocin-induced diabetes in rats. [ABSTRACT FROM AUTHOR]

Background: Euglena gracilis, a photosynthetic protist, produces protein, unsaturated fatty acids, wax esters, and a unique β-1,3-glucan called paramylon, along with other valuable compounds. The cell composition of E. gracilis was investigated in this study to understand how light and organic carbon (photo-, mixo- and heterotrophic conditions) affected growth and cell composition (especially lipids). Comparisons were primarily carried out in cultures grown at 23 °C, but the effect of growth at higher temperatures (27 or 30 °C) was also considered. Cell growth: Specific growth rates were slightly lower when E. gracilis was grown on glucose in either heterotrophic or mixotrophic conditions than when grown photoautotrophically, although the duration of exponential growth was longer. Temperature determined the rate of exponential growth in all cultures, but not the linear growth rate during light-limited growth in phototrophic conditions. Temperature had less effect on cell composition. Cell composition: Although E. gracilis was not expected to store large amounts of paramylon when grown phototrophically, we observed that phototrophic cells could contain up to 50% paramylon. These cells contained up to 33% protein and less than 20% lipophilic compounds, as expected. The biomass contained about 8% fatty acids (measured as fatty acid methyl esters), most of which were unsaturated. The fatty acid content of cells grown in mixotrophic conditions was similar to that observed in phototrophic cells, but was lower in cells grown heterotrophically. Heterotrophic cells contained less unsaturated fatty acids than phototrophic or mixotrophic cells. α-Linolenic acid was present at 5 to 18 mg g-1 dry biomass in cells grown in the presence of light, but at < 0.5 mg g-1 biomass in cells grown in the dark. Eicosapentaenoic and docosahexaenoic acids were detected at 1 to 5 mg g-1 biomass. Light was also important for the production of vitamin E and phytol. [ABSTRACT FROM AUTHOR]

Background: Low birth weight infant (LBWIs) are prone to mental and behavioural problems. As an important constituent of the brain and retina, long chain polyunsaturated fatty acids are essential for foetal infant mental and visual development. The effect of lactation supplemented with long chain polyunsaturated fatty acids (LCPUFA) on the improvement of intelligence in low birth weight children requires further validation. Methods: In this study, a comprehensive search of multiple databases was performed to identify studies focused the association between intelligence and long chain polyunsaturated fatty acid supplementation in LBWIs. Studies that compared the Bayley Scales of Infant Development (BSID) or the Wechsler Abbreviated Scale of Intelligence for Children (WISC) scores between LBWIs who were supplemented and controls that were not supplemented with LCPUFA during lactation were selected for inclusion in the meta-analysis. Results: The main outcome was the mean difference in the mental development index (MDI) and psychomotor development index (PDI) of the BSID and the full scale intelligence quotient (FSIQ), verbal intelligence quotient (VIQ) and performance intelligence quotient (PIQ) of the WISC between LBWIs and controls. Our findings indicated that the mean BSID or WISC scores in LBWIs did not differ between the supplemented groups and controls. Conclusion: This meta-analysis does not reveal that LCPUFA supplementation has a significant impact on the level of intelligence in LBWIs. [ABSTRACT FROM AUTHOR]

Scope: Conjugated linoleic acids are linoleic acid isomers found in the diet that can also be produced through bacterial metabolism of polyunsaturated fatty acids. Our objective was to evaluate the contribution of fatty acid metabolites produced from polyunsaturated fatty acids by the gut microbiota in vivo to regulation of hepatic lipid metabolism and steatosis. Methods and results: In mice with depleted n-3 polyunsaturated fatty acids, we observed an accumulation of trans-11,trans-13 CLA and cis-9,cis-11 conjugated linoleic acids in the liver tissue that were associated with an increased triglyceride content and expression of lipogenic genes. We used an in vitro model to evaluate the impact of these two conjugated linoleic acids on hepatic lipid metabolism. In HepG2 cells, we observed that only trans-11,trans-13 conjugated linoleic acids recapitulated triglyceride accumulation and increased lipogenic gene expression, which is a phenomenon that may implicate the nuclear factors sterol regulatory element binding protein 1c (SREBP-1c) and carbohydrate-responsive element-binding protein (ChREBP). Conclusion: The trans-11,trans-13 conjugated linoleic acids can stimulate hepatic lipogenesis, which supports the conclusion that gut microbiota and related metabolites should be considered in the treatment of non-alcoholic liver disease. [ABSTRACT FROM AUTHOR]

Omega-7 monoenoic fatty acids (ω-7 FAs) are increasingly exploited both for their positive effects on health and for their industrial potential. Some plant species produce fruits or seeds with high amounts of ω-7 FAs. However, the low yields and poor agronomic properties of these plants preclude their commercial use. As an alternative, the metabolic engineering of oilseed crops for sustainable ω-7 FA production has been proposed. Two palmitoyl-ACP desaturases (PADs) catalyzing ω-7 FA biosynthesis were recently identified and characterized in Arabidopsis thaliana, together with MYB115 and MYB118, two transcription factors that positively control the expression of the corresponding PAD genes. In the present research, we examine the biotechnological potential of these new actors of ω-7 metabolism for the metabolic engineering of plant-based production of ω-7 FAs. We placed the PAD and MYB115 coding sequences under the control of a promoter strongly induced in seeds and evaluated these different constructs in A. thaliana. Seeds were obtained that exhibit ω-7 FA contents ranging from 10 to >50% of the total FAs, and these major compositional changes have no detrimental effect on seed germination. [ABSTRACT FROM AUTHOR]

Traditionally, large planktivorous elasmobranchs have been thought to predominantly feed on surface zooplankton during daytime hours. However, the recent application of molecular methods to examine long-term assimilated diets, has revealed that these species likely gain the majority from deeper or demersal sources. Signature fatty acid analysis (FA) of muscle tissue was used to examine the assimilated diet of the giant manta ray Mobula birostris, and then compared with surface zooplankton that was collected during feeding and non-feeding events at two aggregation sites off mainland Ecuador. The FA profiles of M. birostris and surface zooplankton were markedly different apart from similar proportions of arachidonic acid, which suggests daytime surface zooplankton may comprise a small amount of dietary intake for M. birostris. The FA profile of M. birostris muscle was found to be depleted in polyunsaturated fatty acids, and instead comprised high proportions of 18:1ω9 isomers. While 18:1ω9 isomers are not explicitly considered dietary FAs, they are commonly found in high proportions in deep-sea organisms, including elasmobranch species. Overall, the FA profile of M. birostris suggests a diet that is mesopelagic in origin, but many mesopelagic zooplankton species also vertically migrate, staying deep during the day and moving to shallower waters at night. Here, signature FA analysis is unable to resolve the depth at which these putative dietary items were consumed and how availability of this prey may drive distribution and movements of this large filter-feeder. [ABSTRACT FROM AUTHOR]

The regular consumption of long-chain omega-3 polyunsaturated fatty acids (LCO3-PUFAs) results in general health benefits. The intake of LCO3-PUFAs has been reported to contribute to bone metabolism. We aimed to investigate the relationships between dietary intakes of LCO3-PUFAs and bone mineral density (BMD) in Spanish women aged 20–79 years old. A total of 1865 female subjects (20–79 years old) were enrolled, and lumbar (L2, L3, L3 and total spine), hip (femoral neck (FN), femoral trochanter (FT) and Ward’s triangle (WT)) bone mineral density (BMD) were measured by dual energy X-ray absorptiometry (DXA). Dietary intakes of total energy, calcium, vitamin D, alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and n-6 fatty acids (linoleic acid (LA) and arachidonic acid (AA)) were assessed by a self-administered food frequency questionnaire (FFQ). Spearman’s rank correlations between LCO3-PUFAs and BMD were estimated. Partial correlations controlling for age, weight, height, dietary calcium, vitamin D, menopausal status and energy were calculated. A multiple regression analysis was computed to assess significant associations with BMD in this population. After adjustment for potential confounding factors, there were positive correlations between ALA, EPA and DHA intake and BMD. According to the WHO diagnosis criteria for osteoporosis, in this population of normal and osteopenic women, the dietary intake of ALA was also significantly associated with BMD at the hip. In normal women, the dietary intake of DHA was also significantly associated with BMD at the lumbar spine. No significant associations between LCO3-PUFAs and BMD were detected in the lumbar spine of osteopenic or osteoporotic women. The dietary intake of LCO3-PUFAs was positively associated with BMD in Spanish women at both the hips and the lumbar spine. We highlight that the intake of LCO3-PUFAs is not significantly associated with BMD in osteoporotic women; however, the intake of LCO3-PUFAs seems to be positively associated with BMD at both the hips and the lumbar spine in normal and osteopenic women. [ABSTRACT FROM AUTHOR]

Omega-3 fatty acids are products of secondary metabolism, essential for growth and important for human health. Although there are numerous reports of bacterial production of omega-3 fatty acids, less information is available on the biotechnological production of these compounds from bacteria. The production of eicosapentaenoic acid (EPA, 20:5ω3) by a new species of marine bacteria Shewanella electrodiphila MAR441T was investigated under different fermentation conditions. This strain produced a high percentage (up to 26%) of total fatty acids and high yields (mg / g of biomass) of EPA at or below the optimal growth temperature. At higher growth temperatures these values decreased greatly. The amount of EPA produced was affected by the carbon source, which also influenced fatty acid composition. This strain required Na+ for growth and EPA synthesis and cells harvested at late exponential or early stationary phase had a higher EPA content. Both the highest amounts (20 mg g-1) and highest percent EPA content (18%) occurred with growth on L-proline and (NH4)2SO4. The addition of cerulenin further enhanced EPA production to 30 mg g-1. Chemical mutagenesis using NTG allowed the isolation of mutants with improved levels of EPA content (from 9.7 to 15.8 mg g-1) when grown at 15°C. Thus, the yields of EPA could be substantially enhanced without the need for recombinant DNA technology, often a commercial requirement for food supplement manufacture. [ABSTRACT FROM AUTHOR]

Omega-3 fatty acids are products of secondary metabolism, essential for growth and important for human health. Although there are numerous reports of bacterial production of omega-3 fatty acids, less information is available on the biotechnological production of these compounds from bacteria. The production of eicosapentaenoic acid (EPA, 20:5ω3) by a new species of marine bacteria Shewanella electrodiphila MAR441T was investigated under different fermentation conditions. This strain produced a high percentage (up to 26%) of total fatty acids and high yields (mg / g of biomass) of EPA at or below the optimal growth temperature. At higher growth temperatures these values decreased greatly. The amount of EPA produced was affected by the carbon source, which also influenced fatty acid composition. This strain required Na+ for growth and EPA synthesis and cells harvested at late exponential or early stationary phase had a higher EPA content. Both the highest amounts (20 mg g-1) and highest percent EPA content (18%) occurred with growth on L-proline and (NH4)2SO4. The addition of cerulenin further enhanced EPA production to 30 mg g-1. Chemical mutagenesis using NTG allowed the isolation of mutants with improved levels of EPA content (from 9.7 to 15.8 mg g-1) when grown at 15°C. Thus, the yields of EPA could be substantially enhanced without the need for recombinant DNA technology, often a commercial requirement for food supplement manufacture. [ABSTRACT FROM AUTHOR]

The lifespan of cats with non-obstructive kidney stones is shortened compared with healthy cats indicating a need to reduce stone formation and minimize chronic kidney disease. The purpose of this study was to investigate the effects of increasing dietary polyunsaturated fatty acids (PUFA) on urine characteristics. Domestic-short-hair cats (n = 12; mean age 5.6 years) were randomized into two groups and fed one of two dry-cat foods in a cross-over study design. For one week before study initiation, all cats consumed control food that contained 0.07% arachidonic acid (AA), but no eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). Group 1 continued eating control food for 56 days. Group 2 was fed test food for 56 days, which was control food plus fish oil and high-AA oil. Test food contained 0.17% AA, 0.09% EPA and 0.18% DHA. After 56 days, cats were fed the opposite food for another 56 days. At baseline and after each feeding period, serum was analyzed for fatty acid concentrations, and urine for specific gravity, calcium concentration, relative-super-saturation for struvite crystals, and a calcium-oxalate-titrimetric test was performed. After consuming test food, cats had increased (all P<0.001) serum concentrations of EPA (173%), DHA (61%), and AA (35%); decreased urine specific gravity (P = 0.02); decreased urine calcium concentration (P = 0.06); decreased relative-super-saturation for struvite crystals (P = 0.03); and increased resistance to oxalate crystal formation (P = 0.06) compared with cats consuming control food. Oxalate crystal formation was correlated with serum calcium concentration (r = 0.41; P<0.01). These data show benefits for reducing urine stone formation in cats by increasing dietary PUFA. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphisms (SNPs) in the genes encoding the fatty acid desaturase (FADS) and elongase (ELOVL) enzymes affect long-chain polyunsaturated fatty acid (LC-PUFA) production. We aimed to determine if these SNPs are associated with body mass index (BMI) or affect fatty acids (FAs) in pregnant women. Participants (n = 180) from the PREOBE cohort were grouped according to pre-pregnancy BMI: normal-weight (BMI = 18.5–24.9, n = 88) and overweight/obese (BMI≥25, n = 92). Plasma samples were analyzed at 24 weeks of gestation to measure FA levels in the phospholipid fraction. Selected SNPs were genotyped (7 in FADS1, 5 in FADS2, 3 in ELOVL2 and 2 in ELOVL5). Minor allele carriers of rs174545, rs174546, rs174548 and rs174553 (FADS1), and rs1535 and rs174583 (FADS2) were nominally associated with an increased risk of having a BMI≥25. Only for the normal-weight group, minor allele carriers of rs174537, rs174545, rs174546, and rs174553 (FADS1) were negatively associated with AA:DGLA index. Normal-weight women who were minor allele carriers of FADS SNPs had lower levels of AA, AA:DGLA and AA:LA indexes, and higher levels of DGLA, compared to major homozygotes. Among minor allele carriers of FADS2 and ELOVL2 SNPs, overweight/obese women showed higher DHA:EPA index than the normal-weight group; however, they did not present higher DHA concentrations than the normal-weight women. In conclusion, minor allele carriers of FADS SNPs have an increased risk of obesity. Maternal weight changes the effect of genotype on FA levels. Only in the normal-weight group, minor allele carriers of FADS SNPs displayed reduced enzymatic activity and FA levels. This suggests that women with a BMI≥25 are less affected by FADS genetic variants in this regard. In the presence of FADS2 and ELOVL2 SNPs, overweight/obese women showed higher n-3 LC-PUFA production indexes than women with normal weight, but this was not enough to obtain a higher n-3 LC-PUFA concentration. [ABSTRACT FROM AUTHOR]

This study investigated whether intake of cow milk, naturally enriched with polyunsaturated fatty acids (PUFA, omega-3) and polyphenols (from propolis extract and vitamin E), from manipulation of cow’s diet, would result in positive metabolic effects in rats from weaning until adulthood. Male Wistar rats were fed a standard chow diet or a hypercaloric diet (metabolically disturbed rats, obese) which was supplemented with either whole common milk, milk enriched with PUFA (PUFA-M) or milk enriched with PUFA and polyphenols (PUFA/P-M), at 5mL/kg body weight,having water as control. Whole milk supplementation increased initial weight gain and reduced gain in the adulthood of rats. Intake of common milk reduced cholesterol levels in non-obese rats and reduced insulin resistance in obese rats. PUFA-milk showed a decreasing effect on plasma triacylglycerol and VLDL concentrations, increasing plasma HDL concentration and reducing adipocyte size of non-obese rats, but no effect was observed in obese rats. PUFA/P-milk in obese rats resulted in greater deposition of muscle mass and mesenteric fat, with a tendency to lower LDL levels, and resulted a visceral fat accumulation in non-obese rats. Thus, whole common milk and PUFA-rich milk have shown to be beneficial in a normal metabolic condition, whereas common milk and milk enriched with PUFA and polyphenols improve metabolic effects of obesity. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the efficacy of different dietary fruit pomaces in reducing lipid oxidation in the meat of turkeys fed diets with a high content of n-3 polyunsaturated fatty acids (PUFAs). Over a period of 4 weeks before slaughter, turkeys were fed diets with the addition of 5% dried apple, blackcurrant, strawberry and seedless strawberry pomaces (groups AP, BP, SP and SSP, respectively) and 2.5% linseed oil. Pomaces differed in the content (from 5.5 in AP to 43.1 mg/g in SSP) and composition of polyphenols Proanthocyanidins were the main polyphenolic fraction in all pomaces, AP contained flavone glycosides and dihydrochalcones, BP contained anthocyanins, and SP and SSP—ellagitannins. The n-6/n-3 PUFA ratio in all diets was comparable and lower than 2:1. In comparison with groups C and AP, the percentage of n-3 PUFAs in the total fatty acid pool of white meat from the breast muscles of turkeys in groups BP, SP and SSP was significantly higher, proportionally to the higher content of α-linolenic acid in berry pomaces. The fatty acid profile of dark meat from thigh muscles, including the n-6/n-3 PUFA ratio, was similar and lower than 3:1 in all groups. Vitamin A levels in raw breast muscles were higher in group AP than in groups C and BP (P<0.05). The addition of fruit pomaces to turkey diets lowered vitamin E concentrations (P = 0.001) in raw breast muscles relative to group C. Diets supplemented with fruit pomaces significantly lowered the concentration of thiobarbituric acid reactive substances (TBARS) in raw, frozen and cooked meat. Our results indicate that the dietary application of dried fruit pomaces increases the oxidative stability of meat from turkeys fed linseed oil, and strawberry pomace exerted the most desirable effects due to its highest polyphenol content and antioxidant potential. [ABSTRACT FROM AUTHOR]

Sea urchins are broadly recognised as a delicacy and their quality as food for humans is highly influenced by their diet. Lipids in general and the long-chain polyunsaturated fatty acids (LC-PUFA) in particular, are essential nutrients that determine not only the nutritional value of sea urchins but also guarantee normal growth and reproduction in captivity. The contribution of endogenous production (biosynthesis) of LC-PUFA in sea urchins remained unknown. Using Paracentrotus lividus as our model species, we aimed to characterise both molecularly and functionally the repertoire of fatty acyl desaturases (Fads), key enzymes in the biosynthesis of LC-PUFA, in sea urchins. Three Fads, namely FadsA, FadsC1 and FadsC2, were characterised. The phylogenetic analyses suggested that the repertoire of Fads within the Echinodermata phylum varies among classes. On one hand, orthologues of the P. lividus FadsA were found in other echinoderm classes including starfishes, brittle stars and sea cucumbers, thus suggesting that this desaturase is virtually present in all echinoderms. Contrarily, the FadsC appears to be sea urchin-specific desaturase. Finally, a further desaturase termed as FadsB exists in starfishes, brittle stars and sea cucumbers, but appears to be missing in sea urchins. The functional characterisation of the P. lividus Fads confirmed that the FadsA was a Δ5 desaturase with activity towards saturated and polyunsaturated fatty acids (FA). Moreover, our experiments confirmed that FadsA plays a role in the biosynthesis of non-methylene interrupted FA, a group of compounds typically found in marine invertebrates. On the other hand, both FadsC desaturases from P. lividus showed Δ8 activity. The present results demonstrate that P. lividus possesses desaturases that account for all the desaturation reactions required to biosynthesis the physiological essential eicosapentaenoic and arachidonic acids through the so-called “Δ8 pathway”. [ABSTRACT FROM AUTHOR]

Background: Circulating polyunsaturated fatty acid (PUFA) levels are associated with clinical outcomes in cardiovascular diseases including coronary artery disease and chronic heart failure (HF). However, their clinical implications in acute decompensated HF (ADHF) remain unclear. The aim of this study was to investigate the clinical roles of circulating PUFAs in patients with ADHF. Methods: Circulating levels of PUFAs, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA) and dihomo-gamma linoleic acid (DGLA), were measured on admission in 685 consecutive ADHF patients. Adverse events were defined as all-cause death and worsening HF. Results: During a median follow-up period of 560 days, 262 (38.2%) patients had adverse events. Although patients with adverse events had lower n-6 PUFA (AA + DGLA) level than those without, n-3 PUFA (EPA + DHA) level was comparable between the groups. Kaplan-Meier analyses showed that lower n-6 PUFA level on admission was significantly associated with the composite of all-cause death and worsening HF, all-cause death, cardiovascular death and worsening HF (p < 0.001, p = 0.005, p = 0.021, p = 0.019, respectively). In a multivariate Cox model, lower n-6 PUFA level was independently associated with increased risk of adverse events (HR 0.996, 95% CI: 0.993–0.999, p = 0.027). Conclusions: Lower n-6 but not n-3 PUFA level on admission was significantly related to worse clinical outcomes in ADHF patients. Measurement of circulating n-6 PUFA levels on admission might provide information for identifying high risk ADHF patients. [ABSTRACT FROM AUTHOR]

Background: Polyunsaturated n-3 and n-6 polyunsaturated fatty acids (PUFA) are precursors of biologically active metabolites that affect blood pressure (BP) regulation. This study investigated the association of n-3 and n-6 PUFA and BP in children and adolescents. Methods: In a subsample of 1267 children aged 2–9 years at baseline of the European IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) cohort whole blood fatty acids were measured by a validated gas chromatographic method. Systolic and diastolic BP was measured at baseline and after two and six years. Mixed-effects models were used to assess the associations between fatty acids at baseline and BP z-scores over time adjusting for relevant covariables. Models were further estimated stratified by sex and weight status. Results: The baseline level of arachidonic acid was positively associated with subsequent systolic BP (β = 0.08, P = 0.002) and diastolic BP (β = 0.07, P<0.001). In thin/normal weight children, baseline alpha-linolenic (β = -1.13, P = 0.003) and eicosapentaenoic acid (β = -0.85, P = 0.003) levels were inversely related to baseline and also to subsequent systolic BP and alpha-linolenic acid to subsequent diastolic BP. In overweight/obese children, baseline eicosapentaenoic acid level was positively associated with baseline diastolic BP (β = 0.54, P = 0.005). Conclusions: Low blood arachidonic acid levels in the whole sample and high n-3 PUFA levels in thin/normal weight children are associated with lower and therefore healthier BP. The beneficial effects of high n-3 PUFA on BP were not observed in overweight/obese children, suggesting that they may have been overlaid by the unfavorable effects of excess weight. [ABSTRACT FROM AUTHOR]

Endocrine therapy is the first-line targeted adjuvant therapy for hormone-sensitive breast cancer. In view of the potential anticancer property of the omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) together with chemotherapy in estrogen receptor alpha (ERα) positive mammary tumors, we have explored the regulation by estradiol of the fatty acid desaturation and elongation enzymes involved in DHA synthesis in the human breast cancer cell line MCF7, which expresses ERα but not ERβ. We demonstrate a robust up-regulation in the expression of the fatty acid elongases Elovl2 and Elovl5 upon estradiol stimulation in MCF7 cells, which was sustained for more than 24 hours. Exposure with the ER inhibitor tamoxifen abolished specifically the Elovl2 but not the Elovl5 expression. Similarly, knock-down of ERα eliminated almost fully the Elovl2 but not the Elovl5 expression. Furthermore, ERα binds to one specific ERE within the Elovl2 enhancer in a ligand dependent manner. The involvement of ERα in the control of especially Elovl2, which plays a crucial role in DHA synthesis, may have potential implications in the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

The fatty acid composition of membrane glycerolipids is a major determinant of Staphylococcus aureus membrane biophysical properties that impacts key factors in cell physiology including susceptibility to membrane active antimicrobials, pathogenesis, and response to environmental stress. The fatty acids of S. aureus are considered to be a mixture of branched-chain fatty acids (BCFAs), which increase membrane fluidity, and straight-chain fatty acids (SCFAs) that decrease it. The balance of BCFAs and SCFAs in USA300 strain JE2 and strain SH1000 was affected considerably by differences in the conventional laboratory medium in which the strains were grown with media such as Mueller-Hinton broth and Luria broth resulting in high BCFAs and low SCFAs, whereas growth in Tryptic Soy Broth and Brain-Heart Infusion broth led to reduction in BCFAs and an increase in SCFAs. Straight-chain unsaturated fatty acids (SCUFAs) were not detected. However, when S. aureus was grown ex vivo in serum, the fatty acid composition was radically different with SCUFAs, which increase membrane fluidity, making up a substantial proportion of the total (<25%) with SCFAs (>37%) and BCFAs (>36%) making up the rest. Staphyloxanthin, an additional major membrane lipid component unique to S. aureus, tended to be greater in content in cells with high BCFAs or SCUFAs. Cells with high staphyloxanthin content had a lower membrane fluidity that was attributed to increased production of staphyloxanthin. S. aureus saves energy and carbon by utilizing host fatty acids for part of its total fatty acids when growing in serum, which may impact biophysical properties and pathogenesis given the role of SCUFAs in virulence. The nutritional environment in which S. aureus is grown in vitro or in vivo in an infection is likely to be a major determinant of membrane fatty acid composition. [ABSTRACT FROM AUTHOR]

Polyunsaturated fatty acyl (PUFA) chains in both the ω3 and ω6 series are essential for normal animal brain development, and cannot be interconverted to compensate for a dietary deficiency of one or the other. Paradoxically, a dietary ω3-PUFA deficiency leads to the accumulation of docosapentaenoate (DPA, 22:5ω6), an ω6-PUFA chain that is normally scarce in the brain. We applied a high-precision LC/MS method to characterize the distribution of DPA chains across phospholipid headgroup classes, the fatty acyl chains with which they were paired, and the extent to which they were oxidatively damaged in the cortical brain of rats on an ω3-deficient diet. Results indicate that dietary ω3-PUFA deficiency markedly increased the concentrations of phospholipids with DPA chains across all headgroup subclasses, including plasmalogen species. The concentrations of phospholipids containing docosahexaenoate chains (22:6ω3) decreased 20–25%, while the concentrations of phospholipids containing arachidonate chains (20:4ω6) did not change significantly. Although DPA chains are more saturated than DHA chains, a larger fraction of DPA chains were monohydroxylated, particularly among diacyl-phosphatidylethanolamines and plasmalogen phosphatidylethanolamines, suggesting that they were disproportionately subjected to oxidative stress. Differences in the pathological significance of ω3 and ω6 oxidation products suggest that greater oxidative damage among the ω6 PUFAs that increase in response to dietary ω3 deficiency may have pathological significance in Alzheimer’s disease. [ABSTRACT FROM AUTHOR]

Introduction: Arachidonic acid (AA) and docosahexaenoic acid (DHA) are important long-chain polyunsaturated fatty acids for neuronal and cognitive development and are ingredients of infant formulae that are recommended but there is no evidence based minimal supplementation level available. The aim of this analysis was to investigate the effect of supplemented AA and DHA on phospholipid metabolism. Methods: Plasma samples of a randomized, double-blind infant feeding trial were used for the analyses of phospholipid species by flow-injection mass spectrometry. Healthy term infants consumed isoenergetic formulae (intervention formula with equal amounts of AA and DHA—IF, control formula without additional AA and DHA—CF) from the first month of life until the age of 120 days. A group of breast milk (BM) -fed infants was followed as a reference. Results: The plasma profile detected in newborns was different from 4 month old infants, irrespective of study group. Most relevant changes were seen in higher level of LPC16:1, LPC20:4, PC32:1, PC34:1 and PC36:4 and lower level of LPC18:0, LPC18:2, PC32:2, PC36:2 and several ether-linked phosphatidylcholines in newborns. The sum of all AA and DHA species at 4 month old infants in the CF group showed level of 40% (AA) and 51% (DHA) of newborns. The supplemented amount of DHA resulted in phospholipid level comparable to BM infants, but AA phospholipids were lower than in BM infants. Interestingly, relative contribution of DHA was higher in ether-linked phosphatidylcholines in CF fed infants, but IF and BM fed infants showed higher overall ether-linked phosphatidylcholines levels. Conclusion: In conclusion, we have shown that infant plasma phospholipid profile changes remarkably from newborn over time and is dependent on the dietary fatty acid composition. A supplementation of an infant formula with AA and DHA resulted in increased related phospholipid species. [ABSTRACT FROM AUTHOR]

Eicosapentaenoic acid (EPA, 20:5Δ5,8,11,14,17) and Docosahexaenoic acid (DHA, 22:6Δ4,7,10,13,16,19) are nutritionally beneficial to human health. Transgenic production of EPA and DHA in oilseed crops by transferring genes originating from lower eukaryotes, such as microalgae and fungi, has been attempted in recent years. However, the low yield of EPA and DHA produced in these transgenic crops is a major hurdle for the commercialization of these transgenics. Many factors can negatively affect transgene expression, leading to a low level of converted fatty acid products. Among these the codon bias between the transgene donor and the host crop is one of the major contributing factors. Therefore, we carried out codon optimization of a fatty acid delta-6 desaturase gene PinD6 from the fungus Phytophthora infestans, and a delta-9 elongase gene, IgASE1 from the microalga Isochrysis galbana for expression in Saccharomyces cerevisiae and Arabidopsis respectively. These are the two key genes encoding enzymes for driving the first catalytic steps in the Δ6 desaturation/Δ6 elongation and the Δ9 elongation/Δ8 desaturation pathways for EPA/DHA biosynthesis. Hence expression levels of these two genes are important in determining the final yield of EPA/DHA. Via PCR-based mutagenesis we optimized the least preferred codons within the first 16 codons at their N-termini, as well as the most biased CGC codons (coding for arginine) within the entire sequences of both genes. An expression study showed that transgenic Arabidopsis plants harbouring the codon-optimized IgASE1 contained 64% more elongated fatty acid products than plants expressing the native IgASE1 sequence, whilst Saccharomyces cerevisiae expressing the codon optimized PinD6 yielded 20 times more desaturated products than yeast expressing wild-type (WT) PinD6. Thus the codon optimization strategy we developed here offers a simple, effective and low-cost alternative to whole gene synthesis for high expression of foreign genes in yeast and Arabidopsis. [ABSTRACT FROM AUTHOR]