-
Biomolecules Apr 2023Plasmalogens are membrane phospholipids with two fatty acid hydrocarbon chains linked to L-glycerol, one containing a characteristic cis-vinyl ether function and the...
Plasmalogens are membrane phospholipids with two fatty acid hydrocarbon chains linked to L-glycerol, one containing a characteristic cis-vinyl ether function and the other one being a polyunsaturated fatty acid (PUFA) residue linked through an acyl function. All double bonds in these structures display the cis geometrical configuration due to desaturase enzymatic activity and they are known to be involved in the peroxidation process, whereas the reactivity through cis-trans double bond isomerization has not yet been identified. Using 1-(1Z-octadecenyl)-2-arachidonoyl--glycero-3-phosphocholine (C18 plasm-20:4 PC) as a representative molecule, we showed that the cis-trans isomerization can occur at both plasmalogen unsaturated moieties, and the product has characteristic analytical signatures useful for omics applications. Using plasmalogen-containing liposomes and red blood cell (RBC) ghosts under biomimetic Fenton-like conditions, in the presence or absence of thiols, peroxidation, and isomerization processes were found to occur with different reaction outcomes due to the particular liposome compositions. These results allow gaining a full scenario of plasmalogen reactivity under free radical conditions. Moreover, clarification of the plasmalogen reactivity under acidic and alkaline conditions was carried out, identifying the best protocol for RBC membrane fatty acid analysis due to their plasmalogen content of 15-20%. These results are important for lipidomic applications and for achieving a full scenario of radical stress in living organisms.
Topics: Plasmalogens; Isomerism; Fatty Acids; Liposomes; Free Radicals; Erythrocyte Membrane
PubMed: 37238600
DOI: 10.3390/biom13050730 -
Biochimica Et Biophysica Acta Nov 2011Fatty aldehydes are important components of the cellular lipidome. Significant interest has been developed towards the analysis of the short chain α,β-unsaturated and... (Review)
Review
Fatty aldehydes are important components of the cellular lipidome. Significant interest has been developed towards the analysis of the short chain α,β-unsaturated and hydroxylated aldehydes formed as a result of oxidation of polyunsaturated fatty acids. Multiple gas chromatography-mass spectrometry (GC/MS) and subsequently liquid chromatography-mass spectrometry (LC/MS) approaches have been developed to identify and quantify short-chain as well as long-chain fatty aldehydes. Due to the ability to non-enzymaticaly form Schiff bases with amino groups of proteins, lipids, and with DNA guanidine, free aldehydes are viewed as a marker or metric of fatty acid oxidation and not the part of intracellular signaling pathways which has significantly limited the overall attention this group of molecules have received. This review provides an overview of current GC/MS and LC/MS approaches of fatty aldehyde analysis as well as discusses technical challenges standing in the way of free fatty aldehyde quantitation.
Topics: Aldehydes; Chromatography, Liquid; Fatty Acids; Gas Chromatography-Mass Spectrometry; Halogenation; Humans; Mass Spectrometry; Plasmalogens
PubMed: 21930240
DOI: 10.1016/j.bbalip.2011.08.018 -
Biochimica Et Biophysica Acta Sep 2012Plasmalogens are a unique class of membrane glycerophospholipids containing a fatty alcohol with a vinyl-ether bond at the sn-1 position, and enriched in polyunsaturated... (Review)
Review
Plasmalogens are a unique class of membrane glycerophospholipids containing a fatty alcohol with a vinyl-ether bond at the sn-1 position, and enriched in polyunsaturated fatty acids at the sn-2 position of the glycerol backbone. These two features provide novel properties to these compounds. Although plasmalogens represent up to 20% of the total phospholipid mass in humans their physiological roles have been challenging to identify, and are likely to be particular to different tissues, metabolic processes and developmental stages. Their biosynthesis starts in peroxisomes, and defects at these steps cause the malformation syndrome, Rhizomelic Chondrodysplasia Punctata (RCDP). The RCDP phenotype predicts developmental roles for plasmalogens in bone, brain, lens, lung, kidney and heart. Recent studies have revealed secondary plasmalogen deficiencies associated with more common disorders and allow us to tease out additional pathways dependent on plasmalogen functions. In this review, we present current knowledge of plasmalogen biology in health and disease.
Topics: Alzheimer Disease; Animals; Biological Transport; Cell Membrane; Glyceryl Ethers; Humans; Lipid Metabolism; Organ Specificity; Oxidation-Reduction; Peroxisomal Disorders; Plasmalogens; Respiratory Tract Diseases; Signal Transduction
PubMed: 22627108
DOI: 10.1016/j.bbadis.2012.05.008 -
Journal of Oleo Science Feb 2021Ethanolamine plasmalogen (PlsEtn), a subclass of ethanolamine glycerophospholipid (EtnGpl), has been reported to have many biological and dietary functions. In terms of...
Ethanolamine plasmalogen (PlsEtn), a subclass of ethanolamine glycerophospholipid (EtnGpl), has been reported to have many biological and dietary functions. In terms of PlsEtn absorption, some studies have reported that PlsEtn is re-esterized at the sn-2 position using lymph cannulation and the everted jejunal sac model. In this study, we aimed to better understand the uptake kinetics of PlsEtn and increase its absorption. We thus compared the uptake kinetics of PlsEtn with that of the lyso-form, in which the fatty acid at the sn-2 position was hydrolyzed enzymatically. Upon administration of EtnGpl (extracted from oysters or ascidians, 75.4 mol% and 88.4 mol% of PlsEtn ratio, respectively), the plasma PlsEtn species in mice showed the highest levels at 4 or 8 hours after administration. In the contrast, administration of the EtnGpl hydrolysate, which contained lysoEtnGpl and free fatty acids, markedly increased the plasma levels of PlsEtn species at 2 h after administration. The area under the plasma concentration-time curve (AUC), especially the AUC of PlsEtn species, was higher with hydrolysate administration than that with EtnGpl administration. These results indicate that EtnGpl hydrolysis accelerated the absorption and metabolism of PlsEtn. Consequently, using a different experimental approach from that used in previous studies, we reconfirmed that PlsEtn species were absorbed via hydrolysis at the sn-2 position, suggesting that hydrolysis in advance could increase PlsEtn uptake.
Topics: Administration, Oral; Animals; Intestinal Absorption; Male; Mice, Inbred ICR; Ostreidae; Plasmalogens; Protein Hydrolysates; Mice
PubMed: 33456005
DOI: 10.5650/jos.ess20223 -
Respiratory Research Dec 2023It is now understood that ferroptosis plays a significant role in the progression of chronic obstructive pulmonary disease (COPD) induced by cigarette smoke extract...
BACKGROUND
It is now understood that ferroptosis plays a significant role in the progression of chronic obstructive pulmonary disease (COPD) induced by cigarette smoke extract (CSE). However, the mechanisms underlying this relationship remain largely unclear.
METHODS
In this study, we established a COPD mouse model through exposure to cigarette smoke particulates, followed by H&E staining, analysis of bronchoalveolar lavage fluid, and immunohistochemistry assay. A549 cells were exposed to increasing concentrations of CSE, with the addition of the ferroptosis activator erastin or the inhibitor Fer-1. Cell viability, LDH (lactate dehydrogenase) release, inflammatory cytokines, total ROS (reactive oxygen species), and lipid ROS were measured using the corresponding assay kits. The acetylation level of GNPAT was determined through immunoprecipitation. We assessed the expression levels of molecules involved in plasmalogen biosynthesis (FAR1, AGPS, and GNPAT), GPX4, and SIRT4 using quantitative real-time PCR, western blot analysis, and immunofluorescence staining.
RESULTS
CSE-induced lung tissue damage was initially observed, accompanied by oxidative stress, ferroptosis, and increased plasmalogen biosynthesis molecules (FAR1, AGPS, and GNPAT). CSE also induced ferroptosis in A549 cells, resulting in reduced cell viability, GSH, and GPX4 levels, along with increased LDH, ROS, MDA (malondialdehyde) levels, oxidized lipids, and elevated FAR1, AGPS, and GNPAT expression. Knockdown of GNPAT mitigated CSE-induced ferroptosis. Furthermore, we found that CSE regulated the acetylation and protein levels of GNPAT by modulating SIRT4 expression. Importantly, the overexpression of GNPAT countered the inhibitory effects of SIRT4 on ferroptosis.
CONCLUSIONS
Our study revealed GNPAT could be deacetylated by SIRT4, providing novel insights into the mechanisms underlying the relationship between CSE-induced ferroptosis and COPD.
Topics: Mice; Animals; Ferroptosis; Reactive Oxygen Species; Plasmalogens; Pulmonary Disease, Chronic Obstructive; Lung; Nicotiana
PubMed: 38041059
DOI: 10.1186/s12931-023-02613-0 -
Frontiers in Cell and Developmental... 2021Neonatal respiratory distress syndrome (NRDS) is a type of newborn disorder caused by the deficiency or late appearance of lung surfactant, a mixture of lipids and... (Review)
Review
Neonatal respiratory distress syndrome (NRDS) is a type of newborn disorder caused by the deficiency or late appearance of lung surfactant, a mixture of lipids and proteins. Studies have shown that lung surfactant replacement therapy could effectively reduce the morbidity and mortality of NRDS, and the therapeutic effect of animal-derived surfactant preparation, although with its limitations, performs much better than that of protein-free synthetic ones. Plasmalogens are a type of ether phospholipids present in multiple human tissues, including lung and lung surfactant. Plasmalogens are known to promote and stabilize non-lamellar hexagonal phase structure in addition to their significant antioxidant property. Nevertheless, they are nearly ignored and underappreciated in the lung surfactant-related research. This report will focus on plasmalogens, a minor yet potentially vital component of lung surfactant, and also discuss their biophysical properties and functions as anti-oxidation, structural modification, and surface tension reduction at the alveolar surface. At the end, we boldly propose a novel synthetic protein-free lung surfactant preparation with plasmalogen modification as an alternative strategy for surfactant replacement therapy.
PubMed: 33681198
DOI: 10.3389/fcell.2021.618102 -
FEBS Letters Sep 2017The biosynthesis of plasmalogens in anaerobic bacteria differs fundamentally from that in animal cells. Firstly, the formation of the alk-1'-enyl ether bond in animal... (Review)
Review
The biosynthesis of plasmalogens in anaerobic bacteria differs fundamentally from that in animal cells. Firstly, the formation of the alk-1'-enyl ether bond in animal cells is oxygen dependent. Secondly, the first step in plasmalogen formation in animal cells is an acylation of dihydroxyacetone phosphate, which has been ruled out as a precursor in anaerobes. In bacteria the alk-1'-enyl ether bond is formed after the fully formed acyl glycerolipids are synthesized. Evidence will be presented for the conversion of the sn-1 acyl-linked chain to an O-alk-1'-enyl ether by an as yet unknown mechanism.
Topics: Acylation; Anaerobiosis; Animals; Clostridium beijerinckii; Dihydroxyacetone Phosphate; Plasmalogens
PubMed: 28617934
DOI: 10.1002/1873-3468.12714 -
Brain Research Bulletin Jan 2023Neuroinflammation (NF) is defined as the activation of brain glial cells that are found in neurodegenerative diseases including Alzheimer's disease (AD). It has been... (Review)
Review
Neuroinflammation (NF) is defined as the activation of brain glial cells that are found in neurodegenerative diseases including Alzheimer's disease (AD). It has been known that an increase in NF could reduce the memory process in the brain but the key factors, associated with NF, behind the dysregulation of memory remained elusive. We previously reported that the NF and aging processes reduced the special phospholipids, plasmalogens (Pls), in the murine brain by a mechanism dependent on the activation of transcription factors, NF-kB and c-MYC. A similar mechanism has also been found in postmortem human brain tissues with AD pathologies and in the AD model mice. Recent evidence showed that these phospholipids enhanced memory and reduced neuro-inflammation in the murine brain. Pls can stimulate the cellular signaling molecules, ERK and Akt, by activating the membrane-bound G protein-coupled receptors (GPCRs). Therefore, recent findings suggest that plasmalogens could be one of the key phospholipids in the brain to enhance memory and inhibit NF.
Topics: Animals; Mice; Humans; Plasmalogens; Signal Transduction; Alzheimer Disease; Cognition; Brain; NF-kappa B
PubMed: 36347405
DOI: 10.1016/j.brainresbull.2022.11.005 -
Frontiers in Cell and Developmental... 2021Plasmalogens are a subclass of cell membrane glycerophospholipids that typically include vinyl- ether bond at the sn-1 position and polyunsaturated fatty acid at the... (Review)
Review
Plasmalogens are a subclass of cell membrane glycerophospholipids that typically include vinyl- ether bond at the sn-1 position and polyunsaturated fatty acid at the sn-2 position. They are highly abundant in the neuronal, immune, and cardiovascular cell membranes. Despite the abundance of plasmalogens in a plethora of cells, tissues, and organs, the role of plasmalogens remains unclear. Plasmalogens are required for the proper function of integral membrane proteins, lipid rafts, cell signaling, and differentiation. More importantly, plasmalogens play a crucial role in the cell as an endogenous antioxidant that protects the cell membrane components such as phospholipids, unsaturated fatty acids, and lipoproteins from oxidative stress. The incorporation of vinyl-ether linked with alkyl chains in phospholipids alter the physicochemical properties (e.g., the hydrophilicity of the headgroup), packing density, and conformational order of the phospholipids within the biomembranes. Thus, plasmalogens play a significant role in determining the physical and chemical properties of the biomembrane such as its fluidity, thickness, and lateral pressure of the biomembrane. Insights on the important structural and functional properties of plasmalogens may help us to understand the molecular mechanism of membrane transformation, vesicle formation, and vesicular fusion, especially at the synaptic vesicles where plasmalogens are rich and essential for neuronal function. Although many aspects of plasmalogen phospholipid involvement in membrane transformation identified through experiments and membrane mimic systems, remain to be confirmed , the compiled data show many intriguing properties of vinyl-ether bonded lipids that may play a significant role in the structural and morphological changes of the biomembranes. In this review, we present the current limited knowledge of the emerging potential role of plasmalogens as a modulator of the biomembrane morphology.
PubMed: 34368127
DOI: 10.3389/fcell.2021.673917 -
Biochimica Et Biophysica Acta Dec 2006Defects in PEX genes impair peroxisome assembly and multiple metabolic pathways confined to this organelle, thus providing the biochemical and molecular bases of the... (Review)
Review
Defects in PEX genes impair peroxisome assembly and multiple metabolic pathways confined to this organelle, thus providing the biochemical and molecular bases of the peroxisome biogenesis disorders (PBD). PBD are divided into two types--Zellweger syndrome spectrum (ZSS) and rhizomelic chondrodysplasia punctata (RCDP). Biochemical studies performed in blood and urine are used to screen for the PBD. DNA testing is possible for all of the disorders, but is more challenging for the ZSS since 12 PEX genes are known to be associated with this spectrum of PBD. In contrast, PBD-RCDP is associated with defects in the PEX7 gene alone. Studies of the cellular and molecular defects in PBD patients have contributed significantly to our understanding of the role of each PEX gene in peroxisome assembly.
Topics: Amino Acid Sequence; Chondrodysplasia Punctata, Rhizomelic; Humans; Membrane Proteins; Molecular Sequence Data; Peroxisomal Disorders; Peroxisomes; Pipecolic Acids; Plasmalogens; Refsum Disease, Infantile; Zellweger Syndrome
PubMed: 17055079
DOI: 10.1016/j.bbamcr.2006.09.010