Browsing by Subject "Phospholipid"

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    Age-related changes in mitochondrial membrane composition of nothobranchius rachovii
    (Oxford University Press, 2013-05-17) Lucas-Sánchez, Alejandro; Almaida Pagán, Pedro Francisco; Tocher, Douglas R.; Mendiola, Pilar; Costa, Jorge de; Fisiología
    Mitochondrial membrane composition may be a critical factor in the mechanisms of the aging process by influencing the propagation of reactions involved in mitochondrial function during periods of high stress. Changes affecting either lipid class or fatty acid compositions could affect phospholipid properties and alter mitochondrial function and cell viability In the present study, mitochondrial membrane phospholipid compositions were analyzed throughout the life cycle of Nothobranchius rachovii. Mitochondrial phospholipids showed several changes with age. Proportions of cardiolipin decreased and those of sphingomyelin increased between 11- and 14-month-old fish. Fatty acid compositions of individual phospholipids in mitochondria were also significantly affected with age. These data suggest increasing damage to mitochondrial lipids during the life cycle of N. rachovii that could be one of the main factors related with and contributing to degraded mitochondrial function associated with the aging process.
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    Age-related changes in mitochondrial membrane composition of rainbow trout (Oncorhynchus mykiss) heart and brain
    (Elsevier, 2012-05-22) Almaida Pagán, Pedro Francisco; Costa, J. de; Mendiola, P; Tocher, D R; Fisiología; Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling FK9 4LA, Scotland, United Kingdom; Department of Physiology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain
    Membrane composition, particularly of mitochondria, could be a critical factor by determining the propaga-tion of reactions involved in mitochondrial function during periods of high oxidative stress such as rapid growth and aging. Considering that phospholipids not only contribute to the structural and physical properties of biological membranes, but also participate actively in cell signaling and apoptosis, changes affecting either class or fatty acid compositions could affect phospholipid properties and, thus, alter mitochondrial function and cell viability. In the present study, heart and brain mitochondrial membrane phospholipid compositions were analyzed in rainbow trout during the four first years of life, a period characterized by rapid growth and a sustained high metabolic rate. Specifically, farmed fish of three ages (1-, 2- and 4-years) were studied, and phospholipid class compositions of heart and brain mitochondria, and fatty acid compositions of individual phospholipid classes were determined. Rainbow trout heart and brain mitochon- dria showed different phospholipid compositions (class and fatty acid), likely related to tissue-specific functions. Furthermore, changes in phospholipid class and fatty acid compositions with age were also tissue-dependent. Heart mitochondria had lower proportions of cardiolipin (CL), phosphatidylserine (PS) and phosphatidylinositol, and higher levels of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) with age. Heart mitochondrial membranes became more unsaturated with age, with a significative increase of peroxidation index in CL, PS and sphingomyelin (SM). Therefore, heart mitochondria became more susceptible to oxidative damage with age. In contrast, brain mitochondrial PC and PS content decreased in 4-year-old animals while there was an increase in the proportion of SM. The three main phospholipid classes in brain (PC, PE and PS) showed decreased n−3 polyunsaturated fatty acids, docosahexaenoic acid and peroxidation index, which indicate a different response of brain mitochondrial lipids to rapid growth and maturation.
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    Dietary fatty acids affect mitochondrial phospholipid compositions and mitochondrial gene expression of rainbow trout liver at different ages
    (Springer, 2014-11-15) Almaida Pagán, Pedro Francisco; De Santis, C; Rubio-Mejia, O L; Tocher, D R; Fisiología
    Mitochondria are among the first responders to various stressors that challenge the homeostasis of cells and organisms. Mitochondrial decay is generally associated with impairment in the organelle bioenergetics function and increased oxidative stress, and it appears that deterioration of mitochondrial inner membrane phospholipids (PL), particularly cardiolipin (CL), and accumulation of mitochondrial DNA (mtDNA) mutations are among the main mechanisms involved in this process. In the present study, liver mitochondrial membrane PL compositions, lipid peroxidation, and mtDNA gene expression were analyzed in rainbow trout fed three diets with the same base formulation but with lipid supplied either by fish oil (FO), rapeseed oil (RO), or high DHA oil (DHA) during 6 weeks. Specifically, two feeding trials were performed using fish from the same population of two ages (1 and 3 years), and PL class compositions of liver mitochondria, fatty acid composition of individual PL classes, TBARS content, and mtDNA expression were determined. Dietary fatty acid composition strongly affected mitochondrial membrane composition from trout liver but observed changes did not fully reflect the diet, particularly when it contained high DHA. The changes were PL specific, CL being particularly resistant to changes in DHA. Some significant differences observed in expression of mtDNA with diet may suggest long-term dietary effects in mitochondrial gene expression which could affect electron transport chain function. All the changes were influenced by fish age, which could be related to the different growth rates observed between 1- and 3-year-old trout but that could also indicate age-related changes in the ability to maintain structural homeostasis of mitochondrial membranes.
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    Docosahexaenoic acid supplementation during pregnancy as phospholipids or triglycerides produces different placental uptake but similar fetal brain accretion in neonatal piglets
    (CAMBRIDGE UNIVERSITY PRESS, 2017-11-23) Gázquez, Antonio; Ruíz-Palacios, María; Larqué Daza, Elvira; Fisiología
    The great variety of n-3 long chain polyunsaturated fatty acid sources raises the question of the most adequate for using as a docosahexaenoic acid (DHA) supplement during pregnancy. Placental and fetal availability of different DHA sources remains unclear. We investigated DHA availability in maternal lipoproteins, placenta and fetal tissues in pregnant sows fed DHA as phospholipid (PL) or triglyceride (TG) to identify the best DHA source during this period. Pregnant Iberian sows were fed with diets containing 0.8% DHA of total fatty acids as PL from egg yolk or TG from algae oil during the last third of gestation (40 days). Maternal tissues, placentas and fetal tissues were obtained at delivery and DHA quantified by gas-chromatography. MFSD2a carrier expression was analysed in both placenta and fetal brain by western blotting. Sows fed DHA-PL diet showed higher DHA incorporation in plasma LDL but not in plasma total lipids. No differences were found in DHA content between groups in maternal liver, adipose tissue or brain. Placental tissue incorporated more DHA in both total lipids and PL fraction in sows fed DHA-PL. However, this did not lead to an enhanced DHA accretion either in fetal plasma, fetal liver or fetal brain. MFSD2a expression was similar between both experimental groups. Maternal DHA supplementation during pregnancy in sow either as PL or TG produces similar DHA accretion in fetal tissues but not in placenta. Both fat sources are equally available for fetal brain.
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    Effects of dietary fatty acids on mitochondrial phospholipid compositions, oxidative status and mitochondrial gene expression of zebrafish at different ages
    (Springer, 2015-07-09) Betancor, M B; Almaida Pagán, Pedro Francisco; Hernandez, A; Tocher, D R; Fisiología
    Mitochondrial decay is generally associated with impairment in the organelle ioenergetics function and increased oxidative stress, and it appears that deterioration of mitochondrial inner membrane phospholipids (PL) and accumulation of mitochondrial DNA (mtDNA) mutations are among the main mechanisms involved in this process. In the present study, mitochondrial membrane PL compositions, oxidative status (TBARS content and SOD activity) and mtDNA gene expression of muscle and liver were analyzed in zebrafish fed two diets with lipid supplied either by rapeseed oil (RO) or a blend 60:40 of RO and DHA500 TG oil (DHA). Two feeding trials were performed using zebrafish from the same population of two ages (8 and 21 months). Dietary FA composition affected fish growth in 8-month-old animals, which could be related to an increase in stress promoted by diet composition. Lipid peroxidation was considerably higher in mitochondria of 8-month-old zebrafish fed the DHA diet than in animals fed the RO diet. This could indicate higher oxidative damage to mitochondrial lipids, very likely due to increased incorporation of DHA in PL of mitochondrial membranes. Lipids would be among the first molecules affected by mitochondrial reactive oxygen species, and lipid peroxidation could propagate oxidative reactions that would damage other molecules, including mtDNA. Mitochondrial lipid peroxidation and gene expression of 21-month-old fish showed lower responsiveness to diet composition than those of younger fish. Differences found in the effect of diet composition on mitochondrial lipids between the two age groups could be indicating age-related changes in the ability to maintain structural homeostasis of mitochondrial membranes.