Altered Fatty Acid Profiles Research Articles

English

The use of pesticides is widespread in agricultural activities. These pesticides may contaminate the irrigation and drainage systems during agricultural activities and pests’ control and then negatively affect the biotic and abiotic component of the polluted water courses. The present study aimed to evaluate the effect of the pesticides diazinon and profenofos on some biological activities of Biomphalaria alexandrina snails such as fatty acid profile, some antioxidant enzymes like thioredoxin reductase (TrxR), sorbitol dehydrogenase (SDH), superoxide dismutase (SOD), catalase (CAT) as well as glutathione reductase (GR) and lipid peroxidation (LP) and protein patterns in snails' tissues exposed for 4 weeks to LC10 of diazinon and profenofos. The results showed that the two pesticides caused considerable reduction in survival rates and egg production of treated snails. Identification of fatty acids composition in snails' tissues treated with diazinon and profenofos pesticides was carried out using gas liquid chromatography (GLC). The results declared alteration in fatty acid profile, fluctuation in percent of long chain and short chain fatty acid contributions either saturated or unsaturated ones and a decrease in total lipid content in tissues of snails treated with these pesticides. The data demonstrate that, there was a significant inhibition in the activities of tissues SOD, CAT, GR, TrxR and SDH in tissues of treated snails while a significant elevation was detected in lipid peroxidation as compared to the normal control. On the other hand, the electrophoretic pattern of total protein showed differences in number and molecular weights of protein bands due to snails' treatment. It was concluded that the residues of diazinon and profenofos pesticides in aquatic environments have toxic effects on B. alexandrina snails. Key words: Snails, pesticides, antioxidants, enzymes, fatty acids, proteins, biochemistry.

Fatty acid profiles of Vibrio parahaemolyticus and its changes with environment

The fatty acid (FA) profiles of 15 strains representing four genera (Vibrio, Pseudomonas, Aeromonas, and Shewanella) and seven species were compared by capillary gas chromatography with flame ionization detection. FA fingerprints of Vibrio parahaemolyticus were established by similarity calculation and principle component analysis. This provided a simple measure for distinguishing V. parahaemolyticus from other bacteria. The similarity scores indicated by correlation coefficient and vector cosine were divided into three regions and suggested that the strains with scores higher than 0.980 probably belonged to V. parahaemolyticus. However, samples with low scores (<0.850) were classified under other genera. Furthermore, the alterations in FA profiles of V. parahaemolyticus in the presence of various environmental pressures were investigated. The production of saturated FA (SFA) increased gradually concomitant with a decreased proportion of unsaturated FA (UFA) with rising temperature. Similarly, the SFA tended to increase at the expense of UFA with prolonged culture time. In addition, V. parahaemolyticus changed its FA profiles to contain increased short-chained FA to resist an acidic environment, whereas alkaline conditions stimulated high production of long-chained FA. Analysis on FA profile is valuable for the physiological study of V. parahaemolyticus and its rapid identification.

Subacute ruminal acidosis and total mixed ration preference in lactating dairy cows

Subacute ruminal acidosis (SARA) is a condition where the pH of the rumen becomes abnormally acidic because of increased and altered production of volatile fatty acids. The objective of this experiment was to determine how a SARA challenge affects total mixed ration selection in dairy cows. In this study, 8 multiparous, lactating, ruminally cannulated Holstein cows were given a choice between a long-forage-particle-size diet with slow-fermenting starch (LC) and a short-forage-particle-size diet with fast-fermenting starch in a crossover design. Cows were allowed to adapt to this feeding scheme and were then subjected to a rumen challenge to induce a bout of SARA. The rumen challenge successfully decreased rumen pH and altered rumen volatile fatty acid profiles. Daily average rumen pH decreased from 6.02 to 5.77, and average minimum rumen pH decreased from 5.59 to 5.28. In addition, following the rumen challenge, concentrations of acetate, butyrate, and valerate, and acetate-to-propionate ratio increased. In response to the rumen challenge, intake of LC increased from the baseline level of 18.1% of total daily dry matter intake to 38.3% for that day. During the first recovery day after the rumen challenge, LC intake moderated to 28.0% of total daily dry matter intake. On the second recovery day, LC intake returned to baseline levels at 18.6%. These results indicate that cows are able to alter their diet preference for higher physically effective fiber and slower starch fermentability during a bout of SARA and that they can effectively fully recover from this type of SARA within 72h when appropriate diets are available.

Imaging heterogeneity of membrane and storage lipids in transgenic Camelina sativa seeds with altered fatty acid profiles

Engineering compositional changes in oilseeds is typically accomplished by introducing new enzymatic step(s) and/or by blocking or enhancing an existing enzymatic step(s) in a seed-specific manner. However, in practice, the amounts of lipid species that accumulate in seeds are often different from what one would predict from enzyme expression levels, and these incongruences may be rooted in an incomplete understanding of the regulation of seed lipid metabolism at the cellular/tissue level. Here we show by mass spectrometry imaging approaches that triacylglycerols and their phospholipid precursors are distributed differently within cotyledons and the hypocotyl/radicle axis in embryos of the oilseed crop Camelina sativa, indicating tissue-specific heterogeneity in triacylglycerol metabolism. Phosphatidylcholines and triacylglycerols enriched in linoleic acid (C18:2) were preferentially localized to the axis tissues, whereas lipid classes enriched in gadoleic acid (C20:1) were preferentially localized to the cotyledons. Manipulation of seed lipid compositions by heterologous over-expression of an acyl-acyl carrier protein thioesterase, or by suppression of fatty acid desaturases and elongases, resulted in new overall seed storage lipid compositions with altered patterns of distribution of phospholipid and triacylglycerol in transgenic embryos. Our results reveal previously unknown differences in acyl lipid distribution in Camelina embryos, and suggest that this spatial heterogeneity may or may not be able to be changed effectively in transgenic seeds depending upon the targeted enzyme(s)/pathway(s). Further, these studies point to the importance of resolving the location of metabolites in addition to their quantities within plant tissues.

Effect of Ephedra alata Decne. on lipids metabolism of Aspergillus flavus Link

In Aspergillus flavus Link, the total lipid, sterols, neutral lipids, phospholipids and fatty acid content decreased significantly with the application of different concentrations of Ephedra alata Decne. extrtact. Gas chromatographic analysis revealed the presence of 12 fatty acids namely, (caprylic (C8), capric (C10), lauric (C12), myristic (C14), palmitic (C16), palmitoleic (C16:1), stearic (C18), oleic (C18:1), linoleic (C18:2), ? linolenic (C18:3), arachidic (C20) and arachidonic (C20:4) with total un-saturation per cent 69.78 in the cellular lipids of A. flavus. The use of E. alata extracts induced significant alteration in fatty acid profile towards increment saturation. DOI: http://dx.doi.org/10.3329/bjb.v42i1.15823 Bangladesh J. Bot. 42(1): 45-49, 2013 (June)

Cloning, Characterization and Functional Analysis of Two Type 1 diacylglycerol acyltransferases (DGAT1s) from Tetraena mongolica

Two cDNAs encoding putative type 1 acyl-CoA: diacylglycerol acyltransferases (DGAT1, EC 2.3.1.20), were cloned from Tetraena mongolica, an extreme xerophyte with high oil content in the stems. The 1 488-bp and 1 485-bp of the open reading frame (ORF) of the two cDNAs, designated as TmDGAT1a and TmDGAT1b, were both predicted to encode proteins of 495 and 494 amino acids, respectively. Southern blot analysis revealed that TmDGAT1a and TmDGAT1b both had low copy numbers in the T. mongolica genome. In addition to ubiquitous expression with different intensity in different tissues, including stems, leaves and roots, TmDGAT1a and TmDGAT1b, were found to be strongly induced by high salinity, drought and osmotic stress, resulting in a remarkable increase of triacylglycerol (TAG) accumulation in T. mongolica plantlets. TmDGAT1a and TmDGAT1b activities were confirmed in the yeast H1246 quadruple mutant (DGA1, LRO1, ARE1, ARE2) by restoring DGAT activity of the mutant host to produce TAG. Overexpression of TmDGAT1a and TmDGAT1b in soybean hairy roots as well as in T. mongolica calli both resulted in an increase in oil content (ranging from 37% to 108%), accompanied by altered fatty acid profiles.

Up‐Regulation of Stearoyl‐CoA Desaturase 1 Increases Liver MUFA Content in Obese Zucker but Not Goto‐Kakizaki Rats

The Goto-Kakizaki (GK) rat is an animal model for spontaneous-onset, non-obese type 2 diabetes. Despite abundant evidence about disorders in metabolism, little information is available about fatty acid metabolism in the liver of GK rats. This study aimed to investigate the characteristics of the fatty acid profile, particularly MUFA, and the mechanism underlying the alterations in fatty acid profiles in the liver of GK rats. The activities of enzymes that participate in the biosynthesis of MUFA, expressions of genes encoding these enzymes, and the fatty acid profile in the liver were compared with those of obese Zucker (fa/fa) (ZF) rats, which are obese and non-diabetic. Stearoyl-CoA desaturase (SCD) activity and SCD1 gene expression were considerably up-regulated in GK rats, and these levels were largely comparable to those in ZF rats. However, the proportions and contents of oleic acid and palmitoleic acid were very low considering the highly elevated activity of SCD in the liver of GK rats, when compared with ZF rats. Palmitoyl-CoA chain elongation (PCE) activity and fatty acid elongase (Elovl6) gene expression were markedly up-regulated in ZF rats, whereas PCE activity was up-regulated much less and Elovl6 gene expression was unchanged in GK rats. These results suggest the possibility that up-regulation of gene expression of Elovl6 along with SCD1 is indispensable to elevate the proportions and contents of oleic acid in the liver.

Plasma fatty acid composition, estimated desaturase activities, and their relation with the metabolic syndrome in a population at high risk of cardiovascular disease

The metabolic syndrome (MetS) is a clustering of various metabolic abnormalities which is associated with increased risk of cardiovascular disease (CVD) and type 2 diabetes mellitus. Due to its increasing prevalence, it has become an important public health concern. Altered fatty acid (FA) composition and desaturase activities have been associated with several metabolic diseases, including MetS. The aim of the present study was to evaluate the relationship of the plasma FA profile and desaturase activities with the MetS in a Mediterranean population at high risk of CVD. Baseline data from 427 participants aged 55-80 years who took part in the interventional PREDIMED study were obtained. Individual FA was determined in plasma and desaturase activities were estimated from product/precursor ratios. Odds ratios (OR) and partial correlation coefficients were used to examine these relations with MetS and its components, respectively. We found higher levels of C14:0, C16:0, C16:1n-7, estimated Δ(9)- or stearoyl-CoA desaturase (SCD), and estimated Δ(6) desaturase (D6D), and lower levels of C18:2n-6 in people with MetS compared to those without it. After adjustment for several confounders, only higher quartiles of C14:0, C16:0, C16:1n-7, and D6D were found to be associated with an increasing prevalence of MetS, while higher quartiles of C18:2n-6 were inversely associated with MetS. High proportions of C14:0, C16:0, C16:1n-7, C20:3n-6, SCD, and D6D, and decreased proportions of C18:2n-6 and estimated Δ(5)-desaturase (D5D) were associated with adverse profiles of several metabolic risk factors. Women showed more unhealthy FA pattern and lipid profiles than men, but only among those with MetS. A FA composition and estimated desaturase activities consisting in high levels of SFA, SCD and D6D, and low levels of PUFA and D5D are associated with increased MetS probability and are characteristic of people presenting MetS, especially women. These findings support those observed in non-Mediterranean populations in which an altered FA profile and estimated desaturase activities are associated with MetS.

Effect of Dietary Fat Sources on the Fatty Acid Composition and Sensory Characteristics of Chicken Meat

The research was carried out in two experiments on Ross 308 male hybrid chickens. Chickens were divided into five groups (five dietary treatments differing in source and concentration of plant oil and fish oil). Feeding chickens with diets of determined composition from 22nd to 42nd day of fattening resulted in altered fatty acid profile in white meat and dark meat, and in significantly lowered n-6/n-3 polyunsaturated fatty acids (PUFA) ratio in white meat. Increase of n-3 PUFA concentration in diets resulted in statistically significant (P = 0.001) increase of n-3 PUFA, as well as in decrease (P = 0.02) of n-6 PUFA in white and dark chicken meat in the 1st experiment. The 2nd experiment resulted in statistically significant increase of n-3 PUFA concentration in white and dark chicken meat (P 0.05). In order to produce chicken meat as functional product, it is possible to reach balance between high n-3 PUFA concentration and satisfactory sensory traits characteristics of chicken meat.

Scientific opinion on application (EFSA-GMO-NL-2010-78) for the placing on the market of herbicide-tolerant, increased oleic acid genetically modified soybean MON 87705 for food and feed uses, import and processing under Regulation (EC) No 1829/2003 from Monsanto

This scientific opinion is a risk assessment of the genetically modified, herbicide-tolerant, increased oleic acid soybean MON 87705 for food and feed uses, import and processing. MON 87705 contains the soybean FAD2-1A/FATB1-A gene fragments down-regulating endogenous FAD2 and FATB enzymes and the CP4 epsps gene cassette conferring tolerance to glyphosate-containing herbicides. Bioinformatic analyses and genetic stability studies did not raise safety issues. The levels of the CP4 EPSPS protein in soybean MON 87705 have been sufficiently analysed. MON 87705 differs from the conventional counterpart in the fatty acid profile (proportion of (C18:1) oleic acid increased and proportions of (C18:2) linoleic acid and (C16:0) palmitic acid decreased) in seeds and the presence of the CP4 EPSPS protein. Scientific risk assessment of soybean MON 87705 was carried out in the context of the intended use as specified by the applicant, namely its use for food and feed as any conventional soybean except for the oil derived from soybean MON 87705, which is to be used in margarine, salad dressing, mayonnaise and home-use liquid vegetable oil, excluding the use of soybean MON 87705 oil for commercial frying. The safety assessment identified no concerns regarding potential toxicity and allergenicity of the CP4 EPSPS protein. The altered fatty acid profile did not raise concerns regarding toxicity. The overall allergenicity of the whole plant was not changed by the genetic modification. The estimated changes in intake levels of these fatty acids do not raise nutritional concerns in the context of the intended use as specified by the applicant. A feeding study on broiler chickens confirmed that defatted meal of soybean MON 87705 is as nutritious as meals produced from its conventional counterpart and non-GM reference varieties. There are no indications of an increased likelihood of establishment and spread of feral soybean plants. Considering its intended uses, environmental risks associated with an unlikely, but theoretically possible, horizontal gene transfer from soybean MON 87705 to bacteria have not been identified. Potential biotic and abiotic interactions of soybean MON 87705 were not considered to be an issue owing to the low level of exposure. The monitoring plan is in line with the intended uses of soybean MON 87705. The EFSA GMO Panel considers that the information available for soybean MON 87705 addresses the scientific comments raised by the Member States and states that soybean MON 87705, as described in the application, is as safe as its conventional counterpart with respect to potential effects on human and animal health and the environment in the context of its intended uses as proposed by the applicant.

Marginal Vitamin B-6 Deficiency Decreases Plasma (n-3) and (n-6) PUFA Concentrations in Healthy Men and Women1–3

Previous animal studies showed that severe vitamin B-6 deficiency altered fatty acid profiles of tissue lipids, often with an increase of linoleic acid and a decrease of arachidonic acid. However, little is known about the extent to which vitamin B-6 deficiency affects human fatty acid profiles. The aim of this study was to determine the effects of marginal vitamin B-6 deficiency on fatty acid profiles in plasma, erythrocytes, and peripheral blood mononuclear cells (PBMC) of healthy adults fed a 28-d, low-vitamin B-6 diet. Healthy participants (n = 23) received a 2-d, controlled, vitamin B-6–adequate diet followed by a 28-d, vitamin B-6–restricted diet to induce a marginal deficiency. Plasma HDL and LDL cholesterol concentrations, FFA concentrations, and erythrocyte and PBMC membrane fatty acid compositions did not significantly change from baseline after the 28-d restriction. Plasma total arachidonic acid, EPA, and DHA concentrations decreased from (mean ± SD) 548 ± 96 to 490 ± 94 μmol/L, 37 ± 13 to 32 ± 13 μmol/L, and 121 ± 28 to 109 ± 28 μmol/L [positive false discovery rate (pFDR) adjustedP < 0.05], respectively. The total (n-6):(n-3) PUFA ratio in plasma exhibited a minor increase from 15.4 ± 2.8 to 16.6 ± 3.1 (pFDR adjustedP < 0.05). These data indicate that short-term vitamin B-6 restriction decreases plasma (n-3) and (n-6) PUFA concentrations and tends to increase the plasma (n-6):(n-3) PUFA ratio. Such changes in blood lipids may be associated with the elevated risk of cardiovascular disease in vitamin B-6 insufficiency.

Effects of dietary betaine on milk yield and milk composition of mid-lactation Holstein dairy cows

Betaine, naturally found in plants and an oxidative product of choline, is converted to acetate in the rumen, which may be used for milk fat synthesis. The objective of this study was to determine the effect of supplemental dietary betaine on milk yield and milk composition. Eighteen Holstein dairy cows (126±5 d in milk; mean ± SD) were randomly assigned to a sequence of treatments of rumen-unprotected betaine at 0, 25, 50, and 100g/d added to a standard lactation ration in a 4×4 Latin square design. Animals were fed individually with feed intake and milk yield recorded daily. Body condition score and body weight were recorded on the last day of each period that lasted 16 d, with milk sampled on the last 2d of each period. Milk composition was determined by a Dairy Herd Improvement Association laboratory and milk fatty acids were determined by gas chromatography. Data collected over the last 2 to 3d were analyzed using the MIXED procedure in SAS (SAS Institute Inc., Cary, NC). Milk yield (mean ± SEM) was increased by betaine when fed at 100g/d (22.4, 22.5, 22.8, 24.1±1.19kg/d for 0, 25, 50, and 100g of betaine/d, respectively). No effect of dietary betaine was detected on dry matter intake, feed efficiency, body weight, or body condition score. Percentages of milk fat, lactose, solids-not-fat, and somatic cell count were not altered; however, protein concentration was decreased by betaine supplementation as compared with the control (3.35, 3.28, 3.27, and 3.28±0.07% for 0, 25, 50, and 100g of betaine/d, respectively). Daily yields of milk protein, fat, lactose, energy-corrected milk, and 3.5% fat-corrected milk did not differ with betaine supplementation. Overall, inclusion of dietary betaine at 100g/d increased milk yield, whereas all levels of betaine supplementation decreased milk protein percent and slightly altered milk fatty acid profile. Further studies are needed to determine the ruminal fermentation characteristics and the optimum rate of supplemental betaine for dairy cows.

Polymorphisms in FADS2 correlated with altered desaturase activity in a type‐2 diabetic cohort

Recent evidence reveals that single nucleotide polymorphisms (SNP) in fatty acid desaturase 2 (FADS2) is correlated with alteration in blood fatty acid profile in some ethnic groups. We aimed to examine effects of FADS2 (intronic SNP, rs174589) on Δ6 and Δ5 desaturase activities based on ratios of 18:3n‐6/18:2n‐6 and 20:4n‐6/20:3n‐6 respectively. In 2008, we cross‐sectionally analyzed erythrocyte fatty acids in type 2 diabetic patients (n=702) recruited from the Diabetes Management through Integrated Delivery System (DMIDS) cohort established in Taiwan. Frequencies of rs174589 genotypes GG, GC and CC were 0.739, 0.234 and 0.027 respectively. Levels of hemoglobin A1c in CC genotypes were significantly different from those of GC and GG genotypes. Δ6 desaturase activity (18:3n‐6/18:2n‐6) was significantly reduced in GC (0.005±0.003, p=0.003) and CC (0.004±0.003, p=0.025) than GG genotypes (0.006±0.003). Similarly, Δ5 desaturase activity (20:4n‐6/20:3n‐6) was significantly diminished in C allele carriers than the GG homozygotes (p&lt;0.05). In conclusion, rs174589 in FADS2 is associated with Δ6 and Δ5 desaturase activities in type 2 diabetes patients and impact of these alterations in fatty acids profiles on clinical parameters warrants further investigation.

Fillet quality and gene transcriptome profiling of heart tissue of Atlantic salmon with pancreas disease (PD)

Pancreas disease (PD) caused by salmonid alphavirus (SAV) results in heavy economical losses for Atlantic salmon (Salmo salar L.) farms in Norway, largely due to mortality, poor performance of fish and deteriorated fillet quality. This study determined the fillet quality and heart gene transcriptome in farmed Atlantic salmon (2.2kg gutted weight) with varying PD pathology at slaughter: group A, SAV negative and PD negative; group B, SAV positive and PD negative; group C, SAV positive and PD positive. Gene expression and fillet quality characteristics of groups A and B were similar. Fish of group C had a thin body shape and pale and abnormally firm fillets with high collagen and low protein content, as well as an altered amino acid and fatty acid profile. They also had a marked reduction of energy metabolism and cell proliferation according to gene expression analyses. It is concluded that salmon infected with PD virus (SAV) may have acceptable fillet quality, but loss of pancreatic tissue may result in poor nutritional status of heart and muscle and unacceptable fillet quality. Hence such fish should not progress toward the market chain.

The effect of dietary concentrate and soya oil inclusion on microbial diversity in the rumen of cattle

Methane emissions from ruminants are a significant contributor to global greenhouse gas production. The aim of this study was to examine the effect of diet on microbial communities in the rumen of steers. The effects of dietary alteration (50 : 50 vs 90 : 10 concentrate-forage ratio, and inclusion of soya oil) on methanogenic and bacterial communities in the rumen of steers were examined using molecular fingerprinting techniques (T-RFLP and automated ribosomal intergenic spacer analysis) and real-time PCR. Bacterial diversity was greatly affected by diet, whereas methanogen diversity was not. However, methanogen abundance was significantly reduced (P = 0.009) in high concentrate-forage diets and in the presence of soya oil (6%). In a parallel study, reduced methane emissions were observed with these diets. The greater effect of dietary alteration on bacterial community in the rumen compared with the methanogen community may reflect the impact of substrate availability on the rumen bacterial community. This resulted in altered rumen volatile fatty acid profiles and had a downstream effect on methanogen abundance, but not diversity. Understanding how rumen microbial communities contribute to methane production and how these microbes are influenced by diet is essential for the rational design of methane mitigation strategies from livestock.

A novel FAD2-1 A allele in a soybean plant introduction offers an alternate means to produce soybean seed oil with 85% oleic acid content

The alteration of fatty acid profiles in soybean to improve soybean oil quality has been a long-time goal of soybean researchers. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition and oxidative stability of soybean oil compared to other oils. In the lipid biosynthetic pathway, the enzyme fatty acid desaturase 2 (FAD2) is responsible for the conversion of oleic acid precursors to linoleic acid precursors in developing soybean seeds. Two genes encoding FAD2-1A and FAD2-1B were identified to be expressed specifically in seeds during embryogenesis and have been considered to hold an important role in controlling the seed oleic acid content. A total of 22 soybean plant introduction (PI) lines identified to have an elevated oleic acid content were characterized for sequence mutations in the FAD 2-1A and FAD2-1B genes. PI 603452 was found to contain a deletion of a nucleotide in the second exon of FAD2-1A. These important SNPs were used in developing molecular marker genotyping assays. The assays appear to be a reliable and accurate tool to identify the FAD 2-1A and FAD2-1B genotype of wild-type and mutant plants. PI 603452 was subsequently crossed with PI 283327, a soybean line that has a mutation in FAD2-1B. Interestingly, soybean lines carrying both homozygous insertion/deletion mutation (indel) FAD2-1A alleles and mutant FAD2-1B alleles have an average of 82-86% oleic acid content, compared to 20% in conventional soybean, and low levels of linoleic and linolenic acids. The newly identified indel mutation in the FAD2-1A gene offers a simple method for the development of high oleic acid commercial soybean varieties.

Effects of Perfluorinated Fatty Acids with Different Carbon Chain Length on Fatty Acid Profiles of Hepatic Lipids in Mice

Alterations by perfluorinated fatty acids (PFCAs) with a chain length of 6-9 carbons in the fatty acid profile of hepatic lipids of mice were investigated. The characteristic changes caused by all the PFCAs examined were increases in the contents and proportions of oleic acid (18 : 1), palmitoleic acid (16 : 1) and 8,11,14-eicosatrienoic acid (20 : 3) in hepatic lipids. Hepatic contents of palmitic acid were also increased by the treatments with the PFCAs. These effects were almost dependent on the hepatic concentrations of PFCA molecules regardless of their carbon chain length. Perfluorooctanoic acid elevated the expressions of mRNA encoding acetyl-CoA carboxylase, fatty acid synthase, malic enzyme, stearoyl-CoA desaturase (SCD) (SCD1 and 2), chain elongase (ELOVL5), Δ6 desaturase (Fads2), 1-acylglycerophosphocholine acyltransferase (LPCAT) (LPCAT3). The four PFCAs examined induced microsomal SCD and LPCAT in hepatic concentration-dependent manners regardless of carbon chain length. One linear regression line was confirmed between LPCAT activity and hepatic concentration of PFCA at wide range of the concentration, whereas the induction of SCD was saturable at relatively low concentration of PFCAs. These results suggest (i) that PFCAs with a chain length of 6-9 carbons change the fatty acid profile of hepatic lipids by increasing contents and proportions of 16 : 1, 18 : 1 and 20 : 3, (ii) that these alterations in fatty acid profile are caused by up-regulation of SCD, de novo fatty acid synthesis, chain elongase and Δ6 desaturase and (iii) that the mechanism underlying SCD induction is, in part, mediated through peroxisome proliferator-activated receptor α.

Plasma fatty acids as diagnostic markers in autistic patients from Saudi Arabia

BackgroundsAutism is a family of developmental disorders of unknown origin. The disorder is characterized by behavioral, developmental, neuropathological and sensory abnormalities, and is usually diagnosed between the ages of 2 and 10 with peak prevalence rates observed in children aged 5-8 years. Recently, there has been heightened interest in the role of plasma free fatty acids (FA) in the pathology of neurological disorders. The aim of this study is to compare plasma fatty acid profiles of Saudi autistic patients with those of age-matching control subjects in an attempt to clarify the role of FA in the etiology of autism.Methods26 autistic patients together with 26-age-matching controls were enrolled in the present study. Methyl esters of FA were extracted with hexane, and the fatty acid composition of the extract was analyzed on a gas chromatography.ResultsThe obtained data proved that fatty acids are altered in the plasma of autistic patients, specifically showing an increase in most of the saturated fatty acids except for propionic acid, and a decrease in most of polyunsaturated fatty acids. The altered fatty acid profile was discussed in relation to oxidative stress, mitochondrial dysfunction and the high lead (Pb) concentration previously reported in Saudi autistic patients. Statistical analysis of the obtained data shows that most of the measured fatty acids were significantly different in autistic patients compared to age -matching controls.ConclusionsReceiver Operating Characteristic (ROC) curve analysis shows satisfactory values of area under the curve (AUC) which could reflect the high degree of specificity and sensitivity of the altered fatty acids as biomarkers in autistic patients from Saudi Arabia.

Changes in the fatty acids in seeds of interspecific hybrids between Brassica napus and Brassica juncea

Mustard (Brassica juncea) accessions from Sri Lanka have a fatty acid profile (FAP) dominated by the undesired erucic acid. Therefore, it is necessary to develop B. juncea lines with canola-quality FAP, carrying reduced erucic acid (&lt;1%) and increased oleic acid (&gt;50%). To improve the FAP, B. juncea accessions were hybridised with spring-type canola (B. napus) varieties grown in Australia. Interspecific crosses between three B. napus cultivars (♂) and B. juncea accessions (♀) gave crossability of 50–65%. Embryo culturing on Lichter medium overcame post-germination barriers to obtain F1 plants. Culturing of ovules 21 days after pollination was successful and embryos were independent of hormones in the culture medium and directly developed into plants. Seeds of interspecific hybrids had a FAP different from parental values, particularly for oleic and erucic acids. The low oleic acid (13%) in B. juncea increased to 23–26% in hybrids and high erucic acid in B. juncea (41%) declined to 21–23% in hybrids. Linoleic and linolenic acids showed little variation from parental values. FAP of F1 hybrids shifted towards that of canola quality. The F2 seeds had zero erucic acid and high oleic acid similar to or exceeding the canola parent. Successful interspecific hybridisation of B. juncea and B. napus was confirmed by altered FAP and molecular markers. Embryo rescue in interspecific hybrids of B. juncea and B. napus is a simple, powerful biotechnological tool to increase genetic diversity and transcend species barriers to transfer desired genes, between the species. By implementing a crossing strategy, there is a potential to improve the FAP of Sri Lankan mustard towards the canola type.

Dose-response effect of fish oil substitution in parturition feed on erythrocyte membrane characteristics and sow performance

The present study aimed to investigate whether n-3 polyunsaturated fatty acids (PUFA) incorporate into erythrocyte membranes of peripartal sows in a dose-responsive manner and whether the altered fatty acid profile affects the cell membrane characteristics. At day 109 of gestation (day 0), 51 sows were divided into five treatment groups. Each group received a diet with a different ratio of fish oil to pork lard for nine consecutive days. Blood samples were taken at day 0 and 10 days later. The fatty acid profile of erythrocytes was determined, as well as the osmotic fragility and oxidative stability of erythrocytes. Thiobarbituric acid reactive substances (TBARS) and ferric reducing ability of plasma (FRAP) were determined in plasma samples. Finally, reproductive and performance parameters of both sows and piglets were recorded until weaning. Supplementation of fish oil during the peripartal period changed the fatty acid profile of erythrocyte membranes in a dose-responsive manner. Although the n-3 PUFA content of erythrocyte membranes increased with increasing amounts of fish oil in the diet, no significant effect on erythrocyte osmotic fragility could be recorded. In contrast, oxidative stability of erythrocytes decreased linearly with increasing amounts of fish oil in the diet. Similarly, both TBARS and FRAP linearly increased with increasing percentages of fish oil in the diet. Neither piglet nor sow performance was influenced by dietary treatments, except for a decrease of both piglet survival and weaning weight with increasing quantities of fish oil supplemented. It is concluded that changes in dietary lipid sources can affect the membrane's fatty acid profile within days, and mainly influences oxidative stability of the cells.