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Neonatal adrenoleukodystrophy/disorders of peroxisomal biogenesis
Published in William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop, Atlas of Inherited Metabolic Diseases, 2020
William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop
The same phenotype can also be found in deficiencies of single peroxisomal enzymes (Figures 63.11–63.13). The enzymes include acylCoA oxidase-1 [31, 32], which phenotype has been referred to as pseudoneonatal ALD, D-bifunctional protein [33, 34], and peroxisomal thiolase-1 [35], which phenotype was originally referred to as pseudo-Zellweger syndrome. In these disorders, VLCFA are elevated, but plasmalogen synthesis is normal. Among these disorders, deficiency of the D-bifunctional enzyme is much more common. This protein has both enoylCoA hydratase and 3-hydroxyacylCoA dehydrogenase activity. Among these patients, three subgroups have been identified [35, 36], one with deficient hydratase activity, one with deficient hydroxyacyl dehydrogenase activity, and one with absent protein and deficiency of both activities.
Diseases of the Nervous System
Published in George Feuer, Felix A. de la Iglesia, Molecular Biochemistry of Human Disease, 2020
George Feuer, Felix A. de la Iglesia
During the regeneration processes the synthesis of phospholipids is very slow and basically does not differ from intact nerves. There is some transient increase into phosphatidylethanolamine and inositol which may represent a role they play in regeneration. The synthesis of ethanolamine plasmalogens the most abundant constituents of the nervous system remains unaltered.
Regulation of the Arachidonic Acid Cascade and PAF Metabolism in Reproductive Tissues
Published in Murray D. Mitchell, Eicosanoids in Reproduction, 2020
John M. Johnston, Noriei Maki, Marlane J. Angle, Dennis R. Hoffman
The preferential release of arachidonic acid by the action of phospholipase has been reported during platelet aggregation39 and in bradykinin-stimulated heart and kidney perfusion systems.40 Loeb and Gross41 have recently purified a phospholipase A2 from sheep platelets that demonstrated a selective hydrolysis of the plasmalogen-GPC, compared to the 1-acyl-GPC species. Kramer et al.42 also purified a phospholipase A2 from human platelets that cleaved the 1-alkyl- and l-acyl-2-arachidonoyl species of GPC to a similar degree. The activity of both of these enzymes was increased in the presence of Ca2+. A Ca2+-independent enzyme has also been described in lung tissue43 and canine myocardium.44 The latter enzyme was selective for plasmalogens. The phospholipase activity in neutrophils45 was Ca2+ independent and showed some preference for arachidonate containing 1-alkyl-glycerophos-pholipids. In experiments by Broekmann et al.,46 the absolute mass of fatty acid liberated in thrombin-stimulated human platelets was measured and reported to be roughly proportional to the amount of fatty acid found at the sn-2 position of phosphatidylethanolamine. Previously, Bills et al.39 had suggested that the release of arachidonic acid during platelet stimulation was primarily from phosphatidylcholine, and others47 have suggested that arachidonic acid was released primarily from phosphatidylethanolamine after first being transferred or converted to ethanolamine plasmalogen.
A review on neuropharmacological role of erucic acid: an omega-9 fatty acid from edible oils
Published in Nutritional Neuroscience, 2022
J. B. Senthil Kumar, Bhawna Sharma
Ethanolamine plasmalogens are conical-shaped myelin lipids that contain a vinyl ether linkage at the sn-1 position and an ester linkage at the sn-2 position [46] (Figure 2). Their conical shape is attributed by the perpendicular orientation of sn-2 acyl chain group which, favours a closer alignment to both the side groups in plasmalogens [47]. Thus, it may enhance the packing density and stability of myelin. Plasmalogens have also been hypothesised to protect the bilayer against oxidation and the action of free radical scavengers. Furthermore, plasmalogens play an important role in signalling pathways related to neuronal survival[48]. For example, the antiapoptotic protective plasmalogen function manifests itself as inhibiting the caspase-9 cell death pathway and preventing hippocampal neuronal death [49]. Plasmalogens are believed to play a particularly important role in AD and PD. Decreased plasmalogens are reported in the brain and blood of PD patients, in animals studies it has been shown that treatment with a plasmalogen precursor is capable of protecting striatal dopamine markers in MPTP model of PD [50]. Similarly, peripheral ethanolamine plasmalogens deficiency was postulated to be a causative factor in AD.
Characterising phospholipids and free fatty acids in patients with schizophrenia: A case-control study
Published in The World Journal of Biological Psychiatry, 2021
Dongfang Wang, Xiaoyu Sun, Michel Maziade, Wei Mao, Chuanbo Zhang, Jingyu Wang, Bing Cao
Plasmalogens are a phospholipid subclass which contains vinyl-ether double bonds in the sn-1 position of the phospholipid. These lipids are ubiquitous throughout cellular membranes and serum lipoproteins. Our findings concerning plasmalogens (plas-PCs and plas-PEs) conform with the available evidence indicating that SCZ was associated with the decrease in plasmalogen blood levels (Kaddurah-Daouk et al. 2012; Wood et al. 2015). Metabolomics study on plasma lipids in SCZ patients showed that reduced plasmalogen levels appeared to be a feature evident at the onset of schizophrenia and after multiple psychotic relapses (Kaddurah-Daouk et al. 2012). In addition to plas-PC and plas-PE containing fatty acids C16:0, C18:0 and C18:1 detected in this metabolomics study, we covered more species of plasmalogens, and further supported that a decline of plasmalogen levels is a characteristic of the disease and not a marker that varies with treatment or recurrent psychotic episodes. Plasmalogens are known to have a biological role in reducing oxidation stress, with several lines of evidence suggesting that these ether lipids serve as endogenous antioxidants (Engelmann et al. 1994; Stenvinkel et al. 2004; Brosche et al. 2007). Thus, decreased plasmalogens in this study and previous studies may be a sign of increased oxidative stress in patients with SCZ. Wood et al. demonstrated that plasmalogens were significantly elevated in the frontal cortex of SCZ patients, which may specifically indicate the dysfunction of oligodendrocyte glycosynapses in the brain (Wood and Holderman 2015).
Visualizing phosphatidylcholine via mass spectrometry imaging: relevance to human health
Published in Expert Review of Proteomics, 2018
Jenny Leopold, Yulia Popkova, Kathrin M. Engel, Jürgen Schiller
In the majority of animal tissues and cells, fatty acids are linked to the glycerol backbone via acyl linkages, that is by ester bonds. However, it should be noted that lipids may also be generated from fatty aldehydes [14]. Under these conditions there are no acyl linkages, but alkyl or alkenyl linkages and the resulting lipids are termed ‘ether-lipids’ or ‘plasmalogens’ [15], respectively. In particular ‘plasmalogens’ are attracting increasing interest due to their importance as natural, very effective, antioxidants [16].