Relative Fatty Acid Levels Research Articles

The influence of light microclimate on the lipid profile and associated transcripts of photosynthetically active grape berry seeds.

Lipids and oils determine the quality and industrial value of grape seeds. Studies with legume seeds demonstrated the influence of light on lipid metabolism and its association with seed photosynthesis. Grape berry seeds are photosynthetically active till mature stage, but mostly during the green stage and veraison. The objective of this work was to compare the lipid profiles of seeds from white grape berries (cv. Alvarinho) growing at two contrasting light microclimates in the canopy (low and high light, LL and HL respectively), previously reported to have distinct photosynthetic competences. Berries were collected at three developmental stages (green, veraison and mature) and from both microclimates, and the seeds were analyzed for their lipid profiles in an untargeted manner using liquid chromatography coupled to high resolution mass spectrometry (LCMS). The seed lipid profiles differed greatly among berry developmental stages, and to a lesser extend between microclimates. The LL microclimate coincided with a higher relative levels of fatty acids specifically at mature stage, while the HL microclimate led to an up-regulation of ceramides at green stage and of triacylglycerols and glycerophospholipids at mature stage. The seed transcript levels of four key genes (VvACCase1, VvΔ9FAD, VvFAD6 and VvLOXO) involved in fatty acid metabolism were analyzed using real-time qPCR. The lipoxygenase gene (VvLOXO) was down- and up-regulated by HL, as compared to LL, in seeds at green and veraison stages, respectively. These results suggest that seed photosynthesis may play distinct roles during seed growth and development, possibly by fueling different lipid pathways: at green stage mainly towards the accumulation of membrane-bound lipid species that are essential for cell growth and maintenance of the photosynthetic machinery itself; and at veraison and mature stages mainly towards storage lipids that contribute to the final quality of the grape seeds.

Comprehensive analysis of the Ppatg3 mutant reveals that autophagy plays important roles in gametophore senescence in Physcomitrella patens

BackgroundAutophagy is an evolutionarily conserved system for the degradation of intracellular components in eukaryotic organisms. Autophagy plays essential roles in preventing premature senescence and extending the longevity of vascular plants. However, the mechanisms and physiological roles of autophagy in preventing senescence in basal land plants are still obscure.ResultsHere, we investigated the functional roles of the autophagy-related gene PpATG3 from Physcomitrella patens and demonstrated that its deletion prevents autophagy. In addition, Ppatg3 mutant showed premature gametophore senescence and reduced protonema formation compared to wild-type (WT) plants under normal growth conditions. The abundance of nitrogen (N) but not carbon (C) differed significantly between Ppatg3 mutant and WT plants, as did relative fatty acid levels. In vivo protein localization indicated that PpATG3 localizes to the cytoplasm, and in vitro Y2H assays confirmed that PpATG3 interacts with PpATG7 and PpATG12. Plastoglobuli (PGs) accumulated in Ppatg3, indicating that the process that degrades damaged chloroplasts in senescent gametophore cells was impaired in this mutant. RNA-Seq uncovered a detailed, comprehensive set of regulatory pathways that were affected by the autophagy mutation.ConclusionsThe autophagy-related gene PpATG3 is essential for autophagosome formation in P. patens. Our findings provide evidence that autophagy functions in N utilization, fatty acid metabolism and damaged chloroplast degradation under non-stress conditions. We identified differentially expressed genes in Ppatg3 involved in numerous biosynthetic and metabolic pathways, such as chlorophyll biosynthesis, lipid metabolism, reactive oxygen species removal and the recycling of unnecessary proteins that might have led to the premature senescence of this mutant due to defective autophagy. Our study provides new insights into the role of autophagy in preventing senescence to increase longevity in basal land plants.

Immunomodulatory activity of hyaluronidase is associated with metabolic adaptations during acute inflammation.

Investigate survival outcomes, and immunological and metabolomic effects of hyaluronidase (Hz) treatment during mouse models of acute inflammation and sepsis. Survival of C57Bl/6 mice was monitored after lethal challenge with lipopolysaccharide (LPS) or cecal and ligation puncture (CLP)-induced sepsis and treated with Hz or saline. Mice were also challenged with LPS and treated with Hz for leukocyte counting, cytokine quantification and determination of metabolomic profiles in the peritoneal fluid. Hz treatment improved survival outcomes after lethal challenge with LPS or CLP-induced sepsis. LPS challenge promoted acute neutrophil accumulation and production of interleukin-1β (IL-1β) and IL-6 in the peritoneum, whereas Hz treatment suppressed neutrophil infiltration and cytokine production. We further characterized the metabolomic alterations caused by LPS challenge, which predicted activity of metabolic pathways related to fatty acids and eicosanoids. Hz treatment had a profound effect over the metabolic response, reflected by reductions of the relative levels of fatty acids. Collectively, these data demonstrate that Hz treatment is associated with metabolic reprogramming of pathways that sustain the inflammatory response.

Intracellular Staphylococcus aureus Elicits the Production of Host Very Long-Chain Saturated Fatty Acids with Antimicrobial Activity.

As a facultative intracellular pathogen, Staphylococcus aureus is able to invade and proliferate within many types of mammalian cells. Intracellular bacterial replication relies on host nutrient supplies and, therefore, cell metabolism is closely bound to intracellular infection. Here, we investigated how S. aureus invasion affects the host membrane-bound fatty acids. We quantified the relative levels of fatty acids and their labelling pattern after intracellular infection by gas chromatography-mass spectrometry (GC-MS). Interestingly, we observed that the levels of three host fatty acids—docosanoic, eicosanoic and palmitic acids—were significantly increased in response to intracellular S. aureus infection. Accordingly, labelling carbon distribution was also affected in infected cells, in comparison to the uninfected control. In addition, treatment of HeLa cells with these three fatty acids showed a cytoprotective role by directly reducing S. aureus growth.

Dose-dependent effect of statins on the change in the content of individual fatty acids of blood serum and their complexes of men and women with secondary prevention of chronic coronary heart disease

Objective. To study the dose-dependent effect of simvastatin on the change of content of individual fatty acids (FA) profile of blood serum and their complexes with secondary prevention of chronic coronary heart disease (CHD) in groups of men and women. Materials and methods. Gas-liquid chromatography-mass spectrometry was used to establish the absolute and relative levels of FA in serum of 155 CHD patients before and after treatment by simvastatin in doses of 40 mg (89 people) and 80 mg (36 people). Results. The statin lowered the content of the FA proportionally by reducing the unsaturated (UFA), mainly polyunsaturated (PUFA) FA, and saturated (SFA) FA. The level of monounsaturated fatty acids (MUFA) decreased in women at a dose of 40 mg. The statin increased endogenous formation of ω6 PUFA, ω9 MUFA, and SFA even (except 80 mg), in group of women (40 mg) – ω3 PUFA, and in men (80 mg) – ω7 MUFA. In women after receiving simvastatin 80 mg, the ratio ω3/ω6 PUFA has been shifted to ω6 PUFA, but in men after receiving simvastatin 40 mg in the direction of ω3 PUFA. Only the dose of 80 mg shifted the ratio of C20:5/C20:4 in the direction of ω3 PUFA. In group of women after receiving simvastatin 40 mg was observed a shift to β-oxidation of C18:1(9), and in men at the dose of 80 mg in the direction of its synthesis. In all cases, increased antioxidant protection of PUFA, but less strong it was at the dose of 40 mg. At the same time the formation of MUFA prevailed over the synthesis of SFA. Absolute content of FA - substrates of energy decreased. In all cases, was noticed the decrease of content of FA this very long chain (C22-26), stronger in women. Conclusion. Simvastatin controlling the quantitative composition of the pool of circulating lipoproteins, FA and cholesterol, is ambiguous, depending on dose, affect the metabolism of fatty acids, changing their quantitative and qualitative composition and performing biological functions.

Altered hepatic lipid metabolism in C57BL/6 mice fed alcohol: a targeted lipidomic and gene expression study

Chronic alcohol consumption is associated with fatty liver disease in mammals. The object of this study was to gain an understanding of dysregulated lipid metabolism in alcohol-fed C57BL/6 mice using a targeted lipidomic approach. Liquid chromatography tandem mass spectrometry was used to analyze several lipid classes, including free fatty acids, fatty acyl-CoAs, fatty acid ethyl esters, sphingolipids, ceramides, and endocannabinoids, in plasma and liver samples from control and alcohol-fed mice. The interpretation of lipidomic data was augmented by gene expression analyses for important metabolic enzymes in the lipid pathways studied. Alcohol feeding was associated with i) increased hepatic free fatty acid levels and decreased fatty acyl-CoA levels associated with decreased mitochondrial fatty acid oxidation and decreased fatty acyl-CoA synthesis, respectively; ii) increased hepatic ceramide levels associated with higher levels of the precursor molecules sphingosine and sphinganine; and iii) increased hepatic levels of the endocannabinoid anandamide associated with decreased expression of its catabolic enzyme fatty acid amide hydrolase. The unique combination of lipidomic and gene expression analyses allows for a better mechanistic understanding of dysregulated lipid metabolism in the development of alcoholic fatty liver disease.

Enhanced tolerance to light stress of transgenic Arabidopsis plants that express the codA gene for a bacterial choline oxidase.

Arabidopsis thaliana was transformed with the codA gene from Arthrobacter globiformis. This gene encodes choline oxidase, an enzyme that converts choline to glycinebetaine. The photosynthetic activity, monitored in terms of chlorophyll fluorescence, of transformed plants was more tolerant to light stress than that of wild-type plants. This enhanced tolerance to light stress was caused by acceleration of the recovery of the photosystem II (PS II) complex from the photo-inactivated state. The transformed plants synthesized glycinebetaine, but no changes were detected in the relative levels of membrane lipids or in the relative levels of fatty acids in the various membrane lipids. Transformation with the codA gene increased levels of H2O2, a by-product of the reaction catalyzed by choline oxidase, by only 50% to 100% under stress or non-stress conditions. The activity of ascorbate peroxidase and, to a lesser extent, that of catalase in transformed plants were significantly higher than in the wild-type plants. These observations suggest that H2O2 produced by choline oxidase in the transformed plants might have stimulated the expression of H2O2 scavenging enzymes, with resultant maintenance of the level of H2O2 within a certain limited range. It appears that glycinebetaine produced in vivo, but not changes in membrane lipids or in the level of H2O2, protected the PS II complex in transformed plants from damage due to light stress.

Influence of clomazone herbicide on postharvest quality of processing squash and pumpkin

Certain cultivars of processing pumpkins and squash, such as Golden Delicious and Butternut squash, are more sensitive to application of clomazone (Command herbicide) than others, resulting in paler coloration of fruit tissues-an undesirable condition for food processors. The objective of this research was to evaluate the influence of clomazone on fruit color retention over time in six processing squash and pumpkin cultivars that exhibited various degrees of clomazone sensitivity. Color retention was monitored by total carotenoid content after curing. Relative levels of fatty acids and peroxidase (POD) and lipoxygenase (LOX) enzyme activities, associated with membrane and pigment integrity in higher plants, were assayed. Total carotenoid content of treated tissue varied, with Golden Delicious and Butternut squash significantly affected by herbicide treatment. Treatments of clomazone resulted in increased POD activity in Turk's Turban and Buttercup squash. No difference was observed for LOX activity in treated or control samples.

Distribution and Mobility of ω3 Fatty Acids in Rainbow Trout Fed Varying Levels and Types of Dietary Lipid

The availability of essential fatty acids in fish neutral lipid to tissue phospholipids was determined under conditions of adequate and inadequate essential fatty acid intake as well as during fasting. Juvenile rainbow trout were fed a semi-purified diet containing varying levels of cod liver oil, with or without supplementary olein. Fatty acid analysis indicated that in all treatments the neutral lipid pool was not turned over during feeding but was enhanced by exogenous or endogenously synthesized fatty acids. Fish that received diets devoid of essential fatty acids maintained virtually all of the docosahexenoic acid originally present in each lipid pool. Fish fed diets containing essential fatty acids deposited them in proportion to the dietary levels. After a 4-week fast, no change was noted in the relative levels of fatty acids in neutral lipid indicating that all fatty acids in neutral lipid were catabolized equally--including essential fatty acids. During fasting there was a selective retention of docosahexenoic and linoleic acids in the phospholipid pool.