Cerebral plasmogens and aldehydes in senescence-accelerated mice P8 and R1 : Acomparison between weaned, adult and aged mice

International audience; In contrast with senescence-accelerated mice R1, SAM P8 show abnormal aging characteristics. Changes occurring during aging could be mainly caused by free radical reactions. The brain is a plasmalogen-rich tissue. These particular phospholipids may act as endogenous antioxidants, be oxidized and release long chain aldehydes and α-hydroxyaldehydes during oxidative stress. The aim of this study was to examine by GC/MS the age- and strain-related levels of plasmalogens, aldehydes and α-hydroxyaldehydes in brain homogenates of SAM P8 and R1 at weaning, 5 months and 9 months of age in order to better understand the differences between both strains. In SAM R1, the evolutio…

Analysis of gangliosides in biological samples by hydrophilic interaction liquid chromatography with electrospray ionization tandem mass spectrometry

International audience

Serum omega-3 fatty acids are not associated with age-related macular degeneration

Revue non indexée dans le JCR.; International audience; Evaluation of: Kabasawa S, Mori K, Horie-Inoue K et al. Associations of cigarette smoking but. not serum fatty acids with age-related macular degeneration in a Japanese population. Ophthalmology 118(6), 1082–1088 (2011). Age-related macular degeneration (AMD) is the leading cause of visual impairment in the elderly. in developed countries. Risk factors for AMD are classified into endogenous nonmodifiable. factors, including genetics and environmental factors such as smoking and dietary habits. Both. epidemiological and experimental studies suggest that dietary omega-3 long-chain fatty acids. would participate to prevent from the develo…

Inflammatory cytokines decrease viability and alter ganglioside profile in retinal pigment epithelium cells

Purpose Early stages of Age related Macular Degeneration (AMD) are characterized by dysfunction and degeneration of the retinal pigment epithelium (RPE) cells, which participate in the death of the overlying photoreceptors ultimately leading to loss of vision. Gangliosides (GG) make a wide and heterogeneous family of sialic-acid-containing glycosphingolipids, composed of a sugar chain branched on a ceramide. They are major components of cellular membranes, particularly abundant in the brain and nervous tissue, including retina. While their developmental and neuroprotective actions have been demonstrated, their precise role in retina’s function and its pathologies is still poorly understood.…

Apparent and quantitative loss of fatty acids and triacylglycerols at frying temperatures

[EN]: Olive and sunflower oils were heated at 180 °C for 5, 10 and 15 hours with the aim of defining the changes in the contents of fatty acid methyl esters (FAME) and triacylglycerols (TAG) under frying conditions. Differences between apparent and real loss of FAME or TAG are defined for an adequate interpretation of the changes taking place at high temperature. Such differences depend on the expression of the results and frequently result in erroneous conclusions. Results showed that from the normalized composition it could be deduced that only the most unsaturated FAME (C18:2) or TAG containing it was significantly altered. However, quantitative data indicated that all the unsaturated FA…

The role of plasmalogens in the photoreactivity of human retinal lipid extracts of different age groups

Purpose: Plasmalogens (PLs) constitute a specific subclass of phospholipids characterized by a vinyl-ether bond in SN-1 position of the glycerol backbone and account for 10% of total phospholipids in the retina, where are considered as sacrificial antioxidants. PLs above 50% of other phospholipids present in the retina contain polyunsaturated fatty acid (PUFA) chain in SN-2 position. In this work we analyzed the influence of PLs on of phospholipids naturally occurring in the human retina (SRL) in a model system and in retinal pigment epithelium cells in vitro. Methods: Lipid composition of human retinal extracts (RLE) has been determined by GC and LC/MS analysis. RLE and SRL with and withou…

Contribution à l’étude de la fraction insaponifiable de trois huiles d’olive issues des variétés Guasto, Rougette et Blanquette plantés dans l’est algérien

The sterol profile of three Algerian virgin olive oils produced from Guasto, Blanquette and Rougette cultivar’s, varieties grown in the East of the country, was established by gas chromatography using a flame ionization detector and coupled to mass spectrometry. Four sterol compounds were identified and characterized in the three oils which are, sitosterol always predominant (43-66%), delta 5-avenasterol (8-13%), stigmasterol (≤ 1,5%) and campesterol (1-2%); one methyl sterol (4-methylsterol) : citrostadienol (4-7%) and two triterpenic alcohols : 24-methylene cycloartanol (10-33%) and cycloartenol (3-13%). These results vary according to campany and variety. Our study shows that most of the…

Diversity of Sterol Composition in Tunisian Pistacia lentiscus Seed Oil

International audience; Pistacia lentiscus L. seed oil is used in some Mediterranean forest area for culinary and medicinal purposes. In this study, we aim to examine, for the first time, the effect of growing area on sterol content of Pistacia lentiscus seed oil. Fruits were harvested from 13 different sites located in northern and central Tunisia. Gas chromatography-flame-ionization detection (GC-FID) was used to quantify sterols and gas chromatography/mass spectrometry (GC/MS) was used to identify them. The major sterol identified was b-sitosterol with a value ranging from 854.12 to 1224.09 mg/kg of oil, thus making up more than 54% of the total sterols. The other two main sterols were c…

Characterization of key aroma compounds in Burgundy truffle

International audience

DHA dose-dependently reduces atherosclerosis: a putative role for its peroxidation metabolites, F4-Neuroprostanes

International audience

Red blood cell plasmalogens and docosahexaenoic acid are independently reduced in primary open-angle glaucoma

International audience; Among several theories involved in the pathogenesis of primary open-angle glaucoma (POAG), the vascular theory considers the disease to be a consequence of reduced ocular blood flow associated with red blood cell abnormalities. Red blood cell membrane structure and function are influenced by their phospholipid composition. We investigated whether specific lipid entities that may affect the membrane physiology, namely, polyunsaturated fatty acids (PUFAs) and plasmalogens, are modified in POAG and whether these potential variations are related to the stage of glaucoma. Blood samples were collected from 31 POAG patients and 10 healthy individuals. The stage of glaucoma …

Circulating plasmalogens in patients with primary open angle glaucoma

Purpose: Neuronal tissues such as the retina contain high amounts of particular phospholipids named “ether-lipids”. Since abnormal blood levels of ether-lipids have been associated with several neurological disorders, we wanted to check whether ether-lipid levels were modified and associated with the severity of POAG. Methods: Blood samples were collected from 41 healthy subjects and 64 POAG patients. Following lipid extraction from erythrocytes, total phospholipids including ether-lipids were isolated using silica cartridges. The fatty acid profile of phospholipids was determined using capillary column gas chromatography (GC). The individual molecular species of phospholipids and ether-lip…

Sample preparation and analysis of gangliosides and phospholipids from plasma by liquid chromatography coupled to mass spectrometry

Gangliosides (GG) and phospholipids (PL) are two classes of complex and polar lipids exhibiting a wide structural heterogeneity. LC/MS offers an access to this huge diversity but also faces some challenges. Efficient extraction and purification sample methods are thus required to perform accurate and reliable analyses. To this end, GG and PL were extracted from human plasma with three solvent mixtures (CHCl3/MeOH/H2O) of increasing polarity, in comparison with the reference Folch method. GG were further purified with a Phree Phospholipid Removal column, whose sorbent is designed to selectively remove PL. GG and PL classes were then separated under HILIC conditions before analysis using a Qq…

Causal Link between n-3 Polyunsaturated Fatty Acid Deficiency and Motivation Deficits

International audience; Reward-processing impairment is a common symptomatic dimension of several psychiatric disorders. However, whether the underlying pathological mechanisms are common is unknown. Herein, we asked if the decrease in the n-3 polyunsaturated fatty acid (PUFA) lipid species, consistently described in these pathologies, could underlie reward-processing deficits. We show that reduced n-3 PUFA biostatus in mice leads to selective motivational impairments. Electrophysiological recordings revealed increased collateral inhibition of dopamine D2 receptor-expressing medium spiny neurons (D2-MSNs) onto dopamine D1 receptor-expressing MSNs in the nucleus accumbens, a main brain regio…

Effects of conjugated linoleic acid isomers toward lipids metabolizing enzymes in male wistar rats

International audience

Analysis of eicosapentaenoic and docosahexaenoic acid geometrical isomers formed during fish oil deodorization.

International audience; Addition of long-chain polyunsaturated fatty acids (LC-PUFAs) from marine oil into food products implies preliminary refining procedures of the oil which thermal process affects the integrity of LC-PUFAs. Deodorization, the major step involving high temperatures, is a common process used for the refining of edible fats and oils. The present study evaluates the effect of deodorization temperature on the formation of LC-PUFA geometrical isomers. Chemically isomerized eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were used as reference samples. Fish oil samples have been deodorized at 180, 220 and 250 °C for 3 h and pure EPA and DHA fatty acid methyl esters…

Alteration of plasmalogens in erythrocytes of patients with diabetic retinopathy

Purpose Plasmalogens are phospholipids characterized by a vinyl ether bond and the preferential esterification of polyunsaturated fatty acids (PUFA). We have shown that the lack of plasmalogens leads to abnormal retinal vascularisation. Because we hypothesize that plasmalogens are negative regulators of vascular development, we aimed to check their circulating levels in patients having a retinal pathology with vascular proliferation. Methods Blood samples were collected from 4 control subjects and 42 patients having proliferative or non-proliferative diabetic retinopathy (DR). Patients were classified according to the stage of DR. The plasmalogen content and the fatty acid composition of er…

Erythrocyte Phospholipid and Polyunsaturated Fatty Acid Composition in Diabetic Retinopathy

Background: Long chain polyunsaturated fatty acids (LCPUFAs) including docosahexaenoic acid and arachidonic acid are suspected to play a key role in the pathogenesis of diabetes. LCPUFAs are known to be preferentially concentrated in specific phospholipids termed as plasmalogens. This study was aimed to highlight potential changes in the metabolism of phospholipids, and particularly plasmalogens, and LCPUFAs at various stages of diabetic retinopathy in humans. Methodology and Principal Findings: We performed lipidomic analyses on red blood cell membranes from controls and mainly type 2 diabetes mellitus patients with or without retinopathy. The fatty acid composition of erythrocytes was det…

Lipid nutrition and eye health

 Revue non indexée dans le JCR.; International audience; According to demographic forecasts, the elderly population will represent a growing part of the developed societies in the near future. Eye diseases are the second most prevalent pathologies after the age of 65 years. Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in western countries. The number of people suffering from ocular pathologies is expected to increase sharply in the near future, becoming a socio-economic burden. Recent data indicate that lipid nutrients may represent new tools in the prevention of eye diseases, and especially AMD.

Gangliosides in the retina: a comparative inventory with brain and other ocular structures

International audience

La teneur hépatique en F4-Neuroprostanes : une variable prédictive majeure de la réduction de la plaque d’athérome

Le fichier annexe contient le livre des résumés; Les propriétés athéroprotectrices des acides gras polyinsaturés de type n-3 à longue chaîne (AGPI n-3 LC), et en particulier de l’acide docosahexaénoique (DHA) ont été largement décrites. Néanmoins, les mécanismes d’action restent encore mal connus. Les recherches se sont récemment orientées vers l’identification des métabolites oxygénés issus des AGPI n-3 LC qui sont de plus en plus considérés comme des effecteurs majeurs de leurs effets athéroprotecteurs. Dans ce contexte, une étude dose-réponse de supplémentation en DHA a été réalisée chez un modèle animal d’athérosclérose (souris LDLR-/-) afin d’étudier les relations entre la progression …

Comparative study of serine-plasmalogens in human retina and optic nerve: identification of atypical species with odd carbon chains

International audience; The objective of this work was to detect and identify phosphatidylserine plasmalogen species in human ocular neurons represented by the retina and the optic nerve. Plasmalogens (vinyl-ether bearing phospholipids) are commonly found in the forms of phosphatidylcholine and phosphatidylethanolamine in numerous mammalian cell types, including the retina. While their biological functions are still unclear, the alteration of cellular plasmalogen content has been associated with several human disorders such as Rhizomelic Chondrodysplasia Punctata Type 2 and Primary Open-Angle Glaucoma.By using liquid-chromatography coupled to high resolution and tandem mass spectrometry, we…

Identification of a circulating biomarker highly associated to retinal omega-3 polyunsaturated fatty acid content: the BLISAR project

International audience

F-2-isoprostanes: review of analytical methods

International audience; F2-isoprostanes (F2-isoPs) represent a new family of biomarkers for oxidative stress generated by free radical attack of membrane-bounded arachidonic acid. Esterified F2-isoPs can be found in tissue or plasma lipids whereas the free form F2-isoPs, hydrolyzed by phospholipase, is mainly present in body fluids. The extent of systematic damage due to oxidative stress within the body can be assessed by the determination of plasma or urine F2-isoPs. The determination of F2-isoPs in clinical practice is not often used due to the complexity to extract the compounds from their biologic matrixes before the analysis step. In most of published protocols, extraction procedure is…

β-Amyrin Synthase1 Controls the Accumulation of the Major Saponins Present in Pea (Pisum sativum)

Abstract The use of pulses as ingredients for the production of food products rich in plant proteins is increasing. However, protein fractions prepared from pea or other pulses contain significant amounts of saponins, glycosylated triterpenes that can impart an undesirable bitter taste when used as an ingredient in foodstuffs. In this article, we describe the identification and characterization of a gene involved in saponin biosynthesis during pea seed development, by screening mutants obtained from two Pisum sativum TILLING (Targeting Induced Local Lesions IN Genomes) populations in two different genetic backgrounds. The mutations studied are located in a gene designated PsBAS1 (β-amyrin s…

Circulating markers of retinal and optic nerve lipids

Purpose Blood lipids are frequently used as a surrogate of lipid composition of peripheral tissues. Even if it is well accepted, such a relationship has never been clearly demonstrated for the eye. The aim of this study was to determine in human samples whether a lipidomic approach based on red blood cells could reveal associations between circulating and ocular lipid profiles. Methods Red blood cells, retinas and optic nerves were collected from 9 human donors. The lipidomic analyses on these tissues were done by both, gas chromatography and liquid chromatography coupled to an electrospray ionization source-mass spectrometer (LC-ESI-MS/MS). Results Gas chromatographic approach did not show…

Association of a predictor of retinal omega-3 polyunsaturated fatty acids with advanced age-related macular degeneration: the BLISAR project

International audience

A detailed identification study on high-temperature degradation products of oleic and linoleic acid methyl esters by GC–MS and GC–FTIR

GC-MS and GC-FTIR were complementarily applied to identify oxidation compounds formed under frying conditions in methyl oleate and linoleate heated at 180ºC. The study was focused on the compounds that originated through hydroperoxide scission that remain attached to the glyceridic backbone in fats and oils and form part of non-volatile molecules. Twenty one short-chain esterified compounds, consisting of 8 aldehydes, 3 methyl ketones, 4 primary alcohols, 5 alkanes and 1 furan, were identified. In addition, twenty non-esterified volatile compounds, consisting of alcohols, aldehydes and acids, were also identified as major non-esterified components. Furanoid compounds of 18 carbon atoms form…

Odorant metabolism catalyzed by olfactory mucosal enzymes influences peripheral olfactory responses in rats.

International audience; A large set of xenobiotic-metabolizing enzymes (XMEs), such as the cytochrome P450 monooxygenases (CYPs), esterases and transferases, are highly expressed in mammalian olfactory mucosa (OM). These enzymes are known to catalyze the biotransformation of exogenous compounds to facilitate elimination. However, the functions of these enzymes in the olfactory epithelium are not clearly understood. In addition to protecting against inhaled toxic compounds, these enzymes could also metabolize odorant molecules, and thus modify their stimulating properties or inactivate them. In the present study, we investigated the in vitro biotransformation of odorant molecules in the rat …

Saliva lipidome: A new source of sensory perception and eating habits markers?

International audience

Apprehending ganglioside diversity: a comprehensive methodological approach

Gangliosides make a wide family of glycosphingolipids ubiquitously expressed in mammalian tissues and particularly abundant in the brain and nervous system. They exhibit a huge diversity due to structural variations in both their oligosaccharidic chain and ceramide moiety, which represent a real analytical challenge. Since their discovery in the 1940s, methods have persistently improved until the emergence of Liquid Chromatography/Mass Spectrometry (LC/MS) which offers a high level of specificity and sensitivity and is suitable with high-throughput profiling studies. We describe here a comprehensive approach relying on various techniques and aiming at fully characterizing gangliosides in bi…

Impact of human salivary components on the release of different flavour molecules

International audience

The paradox of omega 3 PUFAs: autoprotection although highly susceptible to peroxidation

National audience

Thermal degradation of long-chain polyunsatured fatty acids during deodorization of fish oil

International audience; Long-chain polyunsaturated fatty acids (LC-PUFA) of the n-3 series, particularly eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid, have specific activities especially in the functionality of the central nervous system. Due to the occurrence of numerous methylene-interrupted ethylenic double bonds, these fatty acids are very sensitive to air (oxygen) and temperature. Non-volatile degradation products, which include polymers, cyclic fatty acid monomers (CFAM) and geometrical isomers of EPA and DHA, were evaluated in fish oil samples obtained by deodorization under vacuum of semi-refined fish oil at 180, 220 and 250 °C. Polymers are the major degradation products g…

Analysis of pecan nut ([i]Carya illinoinensis[/i]) unsaponifiable fraction. Effect of ripening stage on phytosterols and phytostanols composition

Changes in 4-desmethylsterol, 4-monomethylsterol, 4,4-dimethylsterol and phytostanol composition were quantitatively and qualitatively investigated during the ripening of three varieties of Tunisian-grown pecan nuts (Mahan, Moore and Burkett). These components have many health benefits, especially in lowering LDL-cholesterol and preventing heart disease. The phytosterol composition of whole pecan kernel was quantified by Gas Chromatography-Flame Ionisation Detection (GC-FID) and identified by Gas Chromatography-Mass Spectrometry (GC-MS). Fifteen phytosterols and one phytostanol were quantified. The greatest amount of phytosterols (2852.5 mg/100 g of oil) was detected in Mahan variety at 20 …

Long-term intake of Lacticaseibacillus helveticus enhances bioavailability of omega-3 fatty acids in the mouse retina

Omega-3 (n-3) polyunsaturated fatty acids (PUFAs), particularly docosahexaenoic acid (DHA), are required for the structure and function of the retina. They could also help to prevent or delay the development of retinopathies. Given the accumulating evidence showing the role of gut microbiota in regulating retinal physiology and host lipid metabolism, we evaluated the potential of long-term dietary supplementation with the Gram-positive bacterium Lacticaseibacillus helveticus strain VEL12193 to modulate the retinal n-3 PUFA content. A set of complementary approaches was used to study the impact of such a supplementation on the gut microbiota and host lipid/fatty acid (FA) metabolism. L. helv…

Relationships between oral characteristics, bolus formation and aroma compound releases during the consumption of fat spread in humans

Source : 13th Weurman Flavour Research Symposium - Zaragoza, Spain - September 27th – 30th, 201; International audience; The release and perception of flavour compounds is an important factor for the acceptance of a food product. It is a complex echanism that depends not only on the food’s chemical composition and structure, but also on in-mouth mechanisms involved in its breakdown. To date, most of the studies have been focused on hard or semi-hard product such as cheese for instance (1, 2). Among the works published on dairy product, fat spreads were not considered while they represent an important market. However these products are particularly interesting by their structure and composit…

Gangliosides characterization by high resolution mass spectrometry and ion mobility

Gangliosides (GG) are sialic acid-containing glycosphingolipids particularly abundant in the nervous system. They exhibit a wide variety of structures depending on both the oligosaccharide chain and the ceramide moiety. About 200 GG species have been described so far, but their diversity and biological roles are far from being completely elucidated. An efficient method of identification and quantification is crucial to apprehend this huge heterogeneity. In this study, we focused on the characterization of the ceramide portion of GG, identifying the long chain base (LCB) and the fatty acid. A commercial standard of GD3 was analysed with both a Thermo LTQ-Orbitrap XLTM and a Waters Synapt G2-…

Plasmalogens in the pathogenesis of glaucomatous optic neuropathy

Neuronal tissues such as the retina contain high amounts of plasmalogens. One of their particularities is to concentrate polyunsaturated fatty acids (PUFA) before releasing them specifically. Several data from our laboratory suggest that plasmalogens are involved in the pathophysiology of primary open angle glaucoma (POAG), the second leading cause of blindness worldwide. The different experiments were carried out on human patients with POAG as well as on rodent models of glaucoma. They concerned either the identification of specific alterations of plasmalogen metabolism, or the efficacy of PUFAs to prevent retinal damage. The results have shown a loss of several circulating plasmalogens in…

Lipid composition of the human eye: are red blood cells a good mirror of retinal and optic nerve fatty acids?

International audience; BACKGROUND: The assessment of blood lipids is very frequent in clinical research as it is assumed to reflect the lipid composition of peripheral tissues. Even well accepted such relationships have never been clearly established. This is particularly true in ophthalmology where the use of blood lipids has become very common following recent data linking lipid intake to ocular health and disease. In the present study, we wanted to determine in humans whether a lipidomic approach based on red blood cells could reveal associations between circulating and tissue lipid profiles. To check if the analytical sensitivity may be of importance in such analyses, we have used a do…

Anti-atherogenic action of DHA in LDLR-/- mice: are DHA oxygenated metabolites players in the resolution of inflammation?

National audience

4812 - A0028 Gangliosides in the retina: a comparative inventory with brain and other ocular structures

Purpose: Gangliosides (GG) make an extremely diverse family of glycosphingolipids particularly abundant in the brain and neural tissues. While it is known that alterations in GG metabolism are associated with visual defects, the precise biological roles of these compounds in the retina are still largely unknown. In this context, we performed an exhaustive inventory and thorough characterization of the human eye GG aiming to reveal specificities and common features of the retina compared to other ocular tissues and brain.Methods: Retina, RPE/Choroid, ciliary body, optic nerve and brain samples were collected from deceased human donors (N=7). GG were extracted and analysed by a comprehensive …

Identification and quantification of phosphatidylcholines containing very-long-chain polyunsaturated fatty acid in bovine and human retina using liquid chromatography/tandem mass spectrometry.

The retina is one of the vertebrate tissues with the highest content in polyunsaturated fatty acids (PUFA). A large proportion of retinal phospholipids, especially those found in photoreceptor membranes, are dipolyunsaturated molecular species. Among them, dipolyunsaturated phosphatidylcholine (PC) molecular species are known to contain very-long-chain polyunsaturated fatty acids (VLC-PUFA) from the n-3 and n-6 series having 24-36 carbon atoms (C24-C36) and four to six double bonds. Recent interest in the role played by VLC-PUFA arose from the findings that a protein called elongation of very-long-chain fatty acids 4 (ELOVL4) is involved in their biosynthesis and that mutations in the ELOVL…

Understanding aroma release during fat spread consumption by an integrated approach on oral processing in human

Understanding aroma release during fat spread consumption by an integrated approach on oral processing in human. 14. Weurman Flavour Research Symposium

Quality of dietary supplements in ophthalmology

International audience; Purpose: A rising number of dietary supplements are available to prevent age–related ocular pathologies such as AMD or dry eye syndrome. The purpose of this work was to evaluate the quality of dietary supplements containing omega–3 polyunsaturated fatty acids in terms of lipid, vitamin E and heavy metals composition. Dietary supplements designed for improving mental well–being were included in this study since they should share some similarities.Methods: Twenty dietary complements were analyzed (6 for dry eye prevention, 4 for AMD prevention and 10 for improving mental well–being). Lipids and lipophilic vitamins were extracted. The distribution of the lipid classes w…

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Pre-slaughter stress and lipoperoxidation : protective effect of vitamin E and plant extracts rich in polyphenols given to finishing cattle

National audience

Effect of growing area on tocopherols, carotenoids and fatty acid composition ofPistacia lentiscusedible oil

International audience; In this investigation, we aim to study, for the first time, the effect of the growing area on tocopherols, carotenoids and fatty acid content of Pistacia lentiscus fixed oil. Fruits were harvested from eight different sites located in the north and the centre of Tunisia. Tocopherols, carotenoids and fatty acid content of the fixed oils were determined. The highest carotenoid content was exhibited by Feija oil (10.57 mg/kg of oil). Oueslatia and Tabarka oils displayed the highest alpha-tocopherol content (96.79 and 92.79 mg/kg of oil, respectively). Three major fatty acids were determined: oleic, palmitic and linoleic acids. Oleic acid was the main fatty acid presenti…

Age-Related Changes in the Gut Microbiota Modify Brain Lipid Composition

PMCID: PMC6970973; International audience; Understanding the molecular mechanisms underlying the changes observed during aging is a prerequisite to design strategies to prevent age-related diseases. Aging is associated with metabolic changes, including alteration in the brain lipid metabolism. These alterations may contribute to the development of pathophysiological conditions. Modifications in the gut microbiota composition are also observed during aging. As communication axes exist between the gut microbiota and the brain and knowing that microbiota influences the host metabolism, we speculated on whether age-associated modifications in the gut microbiota could be involved in the lipid ch…

Atheroprotective effects and peroxidation of docosahexaenoic acid: is there a direct link?

International audience

Plasmalogen levels are reduced in erythrocytes from patients with diabetic retinopathy

Plasmalogen levels are reduced in erythrocytes from patients with diabetic retinopathy. annual meeting of the association-for-research-in-vision-and-ophthalmology (ARVO)

Fat sensitivity in humans: oleic acid detection threshold is linked to saliva composition and oral volume

Fat perception is assumed to result, at least in part, from in-mouth non-esterified fatty acids (NEFAs) detection. The aim of this study was to better understand how human oral physiology may govern the sensory sensitivity to NEFAs. For this purpose, the detection thresholds for oleic acid were determined for 17 human subjects with highly varying salivary and oral characteristics, and the thresholds were related to their oral and salivary characteristics with conventional and multidimensional data analysis. These thresholds were tested on a dairy oil-in-water emulsion that was specifically designed to avoid biases caused by differences in the initial structure of the emulsion as a function …

Lipid profiling following intake of the Omega 3 fatty acid DHA identifies the peroxidized metabolites F-4-Neuroprostanes as the best predictors of atherosclerosis prevention

International audience; The anti-atherogenic effects of omega 3 fatty acids, namely eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) are well recognized but the impact of dietary intake on bioactive lipid mediat or profiles remains unclear. Such a profiling effort may offer novel targets for future studies into the mechanism of action of omega 3 fatty acids. The present study aimed to determine the impact of DHA supplementation on the profiles of polyunsaturated fatty acids (PUFA) oxygenated metabolites and to investigate their contribution to therosclerosis prevention. A special emphasis was given to the non-enzymatic metabolites knowing the high susceptibility of DHA to free radical…

Detection of lactobacillic acid in low erucic rapeseed oil--A note of caution when quantifying cyclic fatty acid monomers in vegetable oils.

International audience; The purpose of this work was to identify an unknown component which has been detected during the analysis of cyclic fatty acid monomers (CFAMs) in low erucic acid rapeseed oils (LEAR). A sample of crude LEAR was transformed into fatty acid methyl esters (FAMEs) and hydrogenated using PtO2. The hydrogenated sample was fractionated by reversed-phase high-performance liquid chromatography (RP-HPLC) and the fraction containing the CFAMs transformed into picolinyl esters. Analysing these picolinyl derivatives by gas-liquid chromatography coupled to mass spectrometry (GC-MS) showed that the unknown product observed in LEAR is the 11,12-methylene-octadecanoic acid. This cyc…

Identification and quantification of phosphatidylcholines containing very long chain polyunsaturated fatty acid (VLC-PUFA) in bovine and human retina by liquid chromatography/tandem mass spectrometry

The retina is one of the vertebrate tissues with the highest content in polyunsaturated fatty acids (PUFA). A large proportion of the retinal glycerophospholipids, especially those found in photoreceptor membranes, are dipolyunsaturated molecular species. Among them, dipolyunsaturated phosphatidylcholine molecular species are known to contain very long chain polyunsaturated fatty acids (VLC-PUFA) from the n-3 and n-6 series and having 24 to 36 carbon atoms (C24 to C36) and four to six double bonds. Recent interest in the role of VLC-PUFA arose from the findings that a protein named ELOngation of Very Long chain fatty acids 4 (ELOVL4) is involved in their biosynthesis and that mutations in E…

Oxidation-Induced Increase In Photoreactivity of Bovine Retinal Lipid Extract

Open access original paper Source : 10th EPR Workshop on Applications of EPR in Biology and Medicine, 2016 in Krakow, POLAND.; International audience; The mammalian retina contains a high level of polyunsaturated fatty acids, including docosahexaenoic acid (22:6) (DHA), which are highly susceptible to oxidation. It has been shown that one of the products of DHA oxidation-carboxyethylpyrrole (CEP), generated in situ, causes modifications of retinal proteins and induces inflammation response in the outer retina. These contributing factors may play a role in the development of age-related macular degeneration (AMD). It is also possible that some of the lipid oxidation products are photoreactiv…

Identification and quantitation of tocopherols, carotenoids and triglycerides in edible Pistacia lentiscus oil from Tunisia

International audience; The fruits of Pistacia lentiscus are a source of a fixed oil used in some forested areas for culinary purposes and in traditional medicines. The aim of this study was to evaluate the levels of tocopherols, carotenoids and triglycerides in this oil using high-performance liquid chromatography (HPLC). The results demonstrated the presence of two vitamin E isomers; α- and γ-tocopherols, at respective concentrations of 119 mg and 23 mg per kg of oil. β-carotene, lutein and zeaxanthin were the principal carotenoid molecules identified. β-carotene was the main molecule present, with a level of 6.13 mg/kg oil. Di-unsaturated triglycerides comprised more than half of the tot…

18:2Δ 9c,12t and 18:2 Δ9t,12c are present in our diet, as result of heat treatment of vegetable oils. A nutritional study was carried out in order to obtain more precise information on the conversion of these two isomers into long chain polyunsaturated fatty acids (PUFA) by rat tissues. This in vivo study performed using rat fed with small quantities of mono trans linoleic acid isomers (0.6% of total energy) showed that 18:2 Δ9c,12t was converted into 20:4 Δ5c,8c,11c,14t while 18:2 Δ9t,12c was only slightly converted into 20:4 Δ5c,8c,11t,14c. Furthermore 18:2 Δ9t,12c was preferentially elongated into 20:2 Δ11t,14c. Each C20 metabolite of these mono trans 18:2 isomers was isolated as methyl …

Oxyphytosterols are present in plasma of healthy human subjects

The oxidised derivatives of phytosterols (oxyphytosterols) were identified in plasma samples from thirteen healthy human volunteers, using MS. All the samples contained noticeable quantities of (24R)-5b,6b-epoxy-24-ethylcholestan-3b-ol (b-epoxysitostanol) and (24R)-ethylcholestan-3b,5a,6b-triol (sitostanetriol) and also trace levels of (24R)-5a,6a-epoxy-24-ethylcholestan-3b-ol (a-epoxysitostanol), (24R)-methylcholestan-3b,5a,6b-triol (campestanetriol) and (24R)-ethylch olest-5-en-3b-ol-7-one(7-ketositosterol). The amounts of these oxyphytosterols in plasma varied from 4·8 to 57·2 ng/ml. There are two possibilities concerning the origin of these compounds. First, they could come from the sma…

Associations between erythrocyte and ciliary epithelium phosphatidylcholine concentrations in healthy humans

Modification of the monoaminergic neurotransmitters in frontal cortex and hippocampus by dietary trans alpha linolenic acid in piglets

International audience; The effect of partial isomerization of dietary α-linolenic acid on the monoaminergic neurotransmitters in piglets was studied. After feeding the animals for 14 days with diets containing or not trans α-linolenic acid, neurotransmitters related to the monoaminergic function were quantified in the frontal cortex and in the hippocampus. The partial isomerization of dietary α-linolenic acid resulted in increasing endogenous monoamine levels in the frontal cortex (+55% for dopamine) and was related to a very low incorporation of trans polyunsaturated fatty acids. However, feeding animals with a diet in which the imbalance generated by the isomerization of α-linolenic acid…

Plasma gangliosides and age-related macular degeneration

Purpose Age-related macular degeneration (AMD) is a multifactorial and polygenic disease and is the main cause of vision loss in developed countries after 50 years old. Indeed, dry AMD leads to progressive retinal atrophy and exsudative AMD induces a rapid alteration of the macula through neovascularisation. Gangliosides (GG) make a wide and heterogeneous family of sialic-acid-containing glycosphingolipids, composed of a sugar chain branched on a ceramide. They are major components of cellular membranes and are particularly abundant in the brain and nervous tissue, including retina. They are also found circulating in the plasma. GG are known for their neuroprotective properties in the nervo…

A monophasic extraction for simultaneous analysis of polar and non-polar lipids in brain sample by liquid chromatography – mass spectrometry

International audience

Characterization of key aroma compounds in vegetable proteins foods

International audience; The flavour profile of vegetable proteins food is complex due to the presence of a large number of compounds belonging to different chemical classes. The manufacturing process use many parameters of which temperature plays a role in the generation of volatile compounds.The flavour profile of two vegetable proteins sample (high and low thermal processing) were studied. GC-MS analyses detected and identified 71 aroma compounds (pyrazines, alcohols, ketones, aldehydes) in the two samples. Quantification showed a difference between the two thermal treatments. GC-O analysis described 70 olfactive areas, 39 of which attributed to a chemical compound.

Quantitative analysis of fatty acids on choline- and ethanolamine-phospholipids in human ocular and non-ocular tissues by liquid chromatography/tandem mass spectrometry (LC-ESI-MS/MS)

Quantitative analysis of fatty acids on choline- and ethanolamine-phospholipids in human ocular and non-ocular tissues by liquid chromatography/tandem mass spectrometry (LC-ESI-MS/MS). annual meeting of the association-for-research-in-vision-and-ophthalmology (ARVO)