Higher Proportion Of Phospholipids Research Articles

Protective effect of phospholipids in lipoproteins against diabetic kidney disease: A Mendelian randomization analysis.

The etiology of diabetic kidney disease is complex, and the role of lipoproteins and their lipid components in the development of the disease cannot be ignored. However, phospholipids are an essential component, and no Mendelian randomization studies have yet been conducted to examine potential causal associations between phospholipids and diabetic kidney disease. Relevant exposure and outcome datasets were obtained through the GWAS public database. The exposure datasets included various phospholipids, including those in LDL, IDL, VLDL, and HDL. IVW methods were the primary analytical approach. The accuracy of the results was validated by conducting heterogeneity, MR pleiotropy, and F-statistic tests. MR-PRESSO analysis was utilized to identify and exclude outliers. Phospholipids in intermediate-density lipoprotein (OR: 0.8439; 95% CI: 0.7268-0.9798), phospholipids in large low- density lipoprotein (OR: 0.7913; 95% CI: 0.6703-0.9341), phospholipids in low- density lipoprotein (after removing outliers, OR: 0.788; 95% CI: 0.6698-0.9271), phospholipids in medium low- density lipoprotein (OR: 0.7682; 95% CI: 0.634-0.931), and phospholipids in small low-density lipoprotein (after removing outliers, OR: 0.8044; 95% CI: 0.6952-0.9309) were found to be protective factors. This study found that a higher proportion of phospholipids in intermediate-density lipoprotein and the various subfractions of low-density lipoprotein, including large LDL, medium LDL, and small LDL, is associated with a lower risk of developing diabetic kidney disease.

Outer membrane and phospholipid composition of the target membrane affect the antimicrobial potential of first- and second-generation lipophosphonoxins

Lipophosphonoxins (LPPOs) are small modular synthetic antibacterial compounds that target the cytoplasmic membrane. First-generation LPPOs (LPPO I) exhibit an antimicrobial activity against Gram-positive bacteria; however they do not exhibit any activity against Gram-negatives. Second-generation LPPOs (LPPO II) also exhibit broadened activity against Gram-negatives. We investigated the reasons behind this different susceptibility of bacteria to the two generations of LPPOs using model membranes and the living model bacteria Bacillus subtilis and Escherichia coli. We show that both generations of LPPOs form oligomeric conductive pores and permeabilize the bacterial membrane of sensitive cells. LPPO activity is not affected by the value of the target membrane potential, and thus they are also active against persister cells. The insensitivity of Gram-negative bacteria to LPPO I is probably caused by the barrier function of the outer membrane with LPS. LPPO I is almost incapable of overcoming the outer membrane in living cells, and the presence of LPS in liposomes substantially reduces their activity. Further, the antimicrobial activity of LPPO is also influenced by the phospholipid composition of the target membrane. A higher proportion of phospholipids with neutral charge such as phosphatidylethanolamine or phosphatidylcholine reduces the LPPO permeabilizing potential.

Extraction and Characterization of Phospholipid-Enriched Oils from Antarctic Krill (Euphausia Superba) with Different Solvents

ABSTRACTKrill oils (KOs) were extracted from Antarctic krill using ethanol, hexane, or their mixture (1:2, v/v) with yields of 21.32%, 8.50%, and 18.75%, respectively. The total nitrogen content of the aforementioned oils was 2.76%, 1.06%, and 1.87%, respectively, indicating the presence of lipoprotein. All KOs contained a high proportion of phospholipid (PL) (30.20–64.82% of total lipids) and polyunsaturated fatty acids (PUFA) (30.00–34.94% of total FAs). Among PL, phosphatidylcholine was dominant (89.81–90.60 mol %). In contrast, KO extracted with the mixed solvent had the highest amount of glycerophosphocholine species containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Direct infusion mass spectrometric identification of molecular species of glycerophospholipid in three species of edible whelk from Yellow Sea

Whelk has been exploited commercially as a delicacy for a long time. Although previous studies have suggested that whelk might serve as a potential rich source of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) enriched phospholipid (PL), the molecular species profile of the PL have not been reported yet. In this study, more than 220 molecular species of glycerophospholipid (GP) belonging to eight classes including glycerophosphocholine, glycerophosphoethanolamine, glycerophosphoserine, glycerophosphoinositol, lysoglycerophosphocholine, lysoglycerophosphoethanolamine, lysoglycerophosphoserine and lysoglycerophosphoinositol in three species of edible whelks (Buccinium yokomaruae, Neptunea arthritica cumingi Cosse and Volutharpa ampullaceal) were identified for the first time by using direct infusion tandem mass spectrometric method. Most of the predominant GP molecular species contained n-3 LC-PUFA, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Meanwhile, the whelk lipids contained a high proportion of PL (32.92–55.55% of total lipids) and PUFA (30.45–41.42% of total FA). Among PL, phosphatidylcholine (44.18–65.49mol%) was dominant.

Characterization of lipids in three species of sea urchin

Sea urchin gonad has been regarded as a “healthy” food. Although previous studies have suggested that sea urchin gonad might serve as a potential rich source of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) enriched phospholipid (PL), the molecular species profile of its PL has rarely been reported. In this study, about 200 molecular species of glycerophospholipid (GP), including glycerophosphocholine, glycerophosphoethanolamine, glycerophosphoserine, glycerophosphoinositol, lysoglycerophosphocholine and lysoglycerophosphoethanolamine, in gonads from three species of sea urchin (Glyptocidaris crenularis, Strongylocentrotus intermedius and Strongylocentrotus nudus) were characterized using tandem mass spectrometry. Most of the predominant GP molecular species contained PUFA, especially eicosapentaenoic acid (EPA). Meanwhile, the sea urchin lipids contained a high proportion of PL (39.45–50.30% of total lipids) and PUFA (34.47–46.56% of total FA). Among PL, phosphatidylcholine (67.88–72.58mol%) was dominant. Considering the high level of PUFA enriched GP, sea urchin gonads provide great potential as health-promoting food for human consumption.

Regulation of Galactolipid Biosynthesis by Overexpression of the Rice MGD Gene Contributes to Enhanced Aluminum Tolerance in Tobacco.

Membrane lipid alterations affect Al tolerance in plants, but little is known about the regulation of membrane lipid metabolism in response to Al stress. Transgenic tobacco (Nicotiana tabacum) overexpressing rice monogalactosyldiacylglycerol (MGDG) synthase (OsMGD) gene and wild-type tobacco plants were exposed to AlCl3, and the impact of Al toxicity on root growth, Al accumulation, plasma membrane integrity, lipid peroxidation and membrane lipid composition were investigated. Compared with the wild type, the transgenic plants exhibited rapid regrowth of roots after removal of Al and less damage to membrane integrity and lipid peroxidation under Al stress, meanwhile, the Al accumulation showed no difference between wild-type and transgenic plants. Lipid analysis showed that Al treatment dramatically decreased the content of MGDG and the ratio of MGDG to digalactosyldiacylglycerol (DGDG) in wild-type plants, while it was unchanged in transgenic plants. The stable of MGDG level and the ratio of MGDG/DGDG contribute to maintain the membrane stability and permeability. Moreover, Al caused a significant increase in phospholipids in wild-type plants, resulting in a high proportion of phospholipids and low proportion of galactolipids, but these proportions were unaffected in transgenic plants. The high proportion of phospholipids could contribute to a higher rate of Al3+ binding in the membrane and thereby leads to more membrane perturbation and damage. These results show that the regulation of galactolipid biosynthesis could play an important role in maintaining membrane structure and function under Al stress.

Volatile constituents of cooked bullfrog ( Rana catesbeiana) legs

Volatile extracts obtained from pressure-cooked bullfrog legs by simultaneous steam distillation and solvent extraction were analyzed by gas chromatography–mass spectrometry. Although the raw bullfrog legs used in this study contained 0.6% fat only, the extracts were dominated (qualitatively and quantitatively) by lipid oxidation volatiles such as alkanals, alkenals, alkadienals, alkanols and alkenols. Few Maillard volatiles were found, amongst them 2-acetylthiazole, the only sulfur-containing compound found in the extract. This profile of volatiles may be explained by the high proportion of phospholipids and low concentration of sulfur amino acid cystine in raw bullfrog meat, as previously reported by other researchers. Odour activity values (OAV) of volatiles were also estimated and major OAV compounds were: ( E, E)-2,4-decadienal, ( E, Z)-2,4-decadienal, ( E, Z)-2,6-nonadienal, 1-octanol, and ( E)-2-nonenal. Some of these potent unsaturated aliphatic aldehydes have also been associated with chicken flavour. This may contribute to flavour resemblances between bullfrog and chicken meat.

Can 31P NMR spectroscopy be used to indicate the origins of soil organic phosphates?

The relationship between organic P status of 4 soils, 20 microorganisms isolated from these soils (2 bacteria and 3 fungi for each soil) and 13 dominant plant species of typical natural ecosystems of these soils was evaluated. The soils used were represented by two pairs with different ratios of monoester and diester P, and of DNA and other diester P. A Dystric Podzoluvisol and an alpine Umbric Leptosol were characterized by a relatively high proportion of diester P including much DNA P, while a Calcic Chernozem and subalpine Umbric Leptosol had lower proportion of diesters containing relatively less DNA P. The proportions of P compounds in bacteria and plants were very similar on average, based on the monoester to diester P ratio and on the proportions of different diesters in alkaline extract, whereas fungi contained considerably higher proportions of monoesters and polyphosphates, and a higher proportion of phospholipids in the diester fraction. The results showed that the P org composition of NaOH extracts from different soils was more similar to the composition of extracts from different groups of microorganisms. There was no clear correspondence between soil and microbial diester P proportion and composition. A high proportion of polyphosphate P including pyrophosphate P in soil extracts indicates a significant contribution of fungal P compounds in the soil while the monoester to diester P ratio, and DNA to non-DNA P ratio should be used with caution to interpret the origins of soil P org. The relative contributions of microorganisms and plants to monoester and diester P in soils is only partially understood.

Lipid, FA, and sterol composition of New Zealand green lipped mussel (Perna canaliculus) and Tasmanian blue mussel (Mytilus edulis).

The lipid, FA, and sterol composition of the New Zealand green lipped mussel (NZGLM, Perna canaliculus) and of the Tasmanian blue mussel (TBM, Mytilus edulis) were compared using TLC-FID and GC-MS. The respective mussel species were obtained from three different sites in both New Zealand (NZ) and Tasmania. Lipid class distribution of both mussel species was characterized by a high proportion of phospholipid (PL, 57-79%) and TG (10-25%), FFA (7-12%), and sterols (ST, 12-18%). The NZGLM had higher proportions of TG, FFA, and ST (P < 0.01), whereas the TBM had a higher proportion of PL (P < 0.01). There were higher proportions of total PUFA, saturated FA, n-3 FA, and hydroxy and nonmethylene-interrupted FA (P < 0.05) in the TBM compared with the NZGLM. The major FA in the NZGLM were 16:0 (15-17%), 20:5n-3 (14-20%), and 22:6n-3 (11-17%). The same FA dominated lipids in the TBM, although there were significantly higher proportions of 16:0 (P = 0.000) and 22:6 n-3 (P = 0.003) and lower proportions of 20:5n-3 (P = 0.0072) in the TBM. A novel PUFA, 28:8n-3, was detected in both mussels with higher amounts in the TBM, which probably reflects a greater dietary contribution of dinoflagellates for this species. Cholesterol was the dominant sterol in both mussels. Other major sterols included brassicasterol, 22-methylcholesterol, trans-22-dehydrocholesterol, and desmosterol. There were significant differences (P < 0.05) between the NZGLM and TBM for 12 of the 20 sterols measured. Six sterols showed significant site differences for the NZGLM, and 10 for the TBM. The differences in the FA and sterol composition between the two species may be due to the diet of the NZGLM being more diatom-derived and the diet of the TBM having a greater dinoflagellate component.

Inhibition of tubulin guanosine‐5′‐triphosphatase by lipid peroxides: Protective effects of vitamin A derivatives

AbstractLipid peroxidation of cellular proteins has been postulated to be involved in cellular aging. Given the importance of the cytoskeleton in cellular function, it is a prime candidate as a potential target for the deleterious effects of lipid peroxides. In this study, the effects of lipid peroxides on microtubule assembly have been studied in an in vitro assay system, as have the protective effects of the vitamin A group (β‐carotene, retinal, and retinol). The assay was based on tubulin guanosine‐5′‐triphosphatase (GTPase) activity, which is associated with all steps of microtubule assembly. Soybean lecithin was utilized as the starting point to generate lipid peroxides. Its selection was based on the high proportion of phospholipids in the cellular membrane. Lipid peroxides were generated by photooxidation of lecithin, dissolved in methanol, in the presence of 0.004% methylene blue at 4°C for 8 h. Lipid peroxides (1.0 mg/mL) inhibited tubulin GTPase by 49%, relative to the control. Vitamin A derivatives (retinol, retinal, and β‐carotene) all had the ability to protect against the inhibitory effects of lipid peroxides, presumably owing to their antioxidant activities. This protective effect was more pronounced when utilizing a 30‐min, as opposed to a 15‐min, reaction time. This suggests a relatively slow rate of reaction between the peroxide and vitamin A group. These studies present a mechanism for the ability of vitamin A to inhibit aging of the cell.

Age-related changes in lipid secretion of perfused livers from male Wistar rats donors.

Male Wistar rats show typical age-related variations in the distribution of high-density lipoprotein subfractions that include an increase in HDL1 and a decrease in HDL2 proportion. The role of liver in these variations was evaluated by studying the lipoprotein and bile secretions from perfused livers of 14 +/- 1 and 3.5 +/- 0.5 month old Wistar rats (adult and young animals, respectively). The lipid content of lipoproteins secreted from adult livers was higher in HDL2 fraction and lower in VLDL fraction. The lipid output did not show significant age-related variations in the case of HDL1 fraction. However, the lipoproteins secreted from adult livers contained a higher proportion of phospholipids, and a lower proportion of triacylglycerols in comparison with lipoproteins secreted by young livers. Therefore, the molar ratio of core to surface lipids was lower in lipoproteins secreted by adult livers. Adult livers showed a reduction in bile flow by about 37% with a significantly higher phospholipid secretion. These findings suggest that both the hepatic metabolism of glycerophospholipids and their repartition between plasma and bile compartments are affected by aging process. In conclusion, present data show that the age-related increase in plasma HDL1 proportion, previously observed in this rat strain in vivo, are not due to a higher liver secretion of these particles. Conversely, liver appears to have a major role in the age-related VLDL increase and in the variations of phospholipid lipoprotein secretion.

Fractionation of the lipids of raw egg

AbstractMethod is described for fractionating egg lipids on silicic acid, using a Pye Liquid Chromatograph detector unit to monitor the fractionation. Emulsification difficulties in the extraction of “free” lipids with mixed ethers have been overcome by dispersing the egg in a saline phosphate buffer solution. It has been shown that the “free” lipids of raw egg are predominantly triglycerides and that the “bound” lipids have a higher proportion of phospholipids.

Composition en acides gras des phospholipides dans les lipoproteines seriques anormales de la cholostase

Abnormal lipoproteins were isolated in plasma from patients with cholestasis. These abnormal lipoproteins contain a high proportion of phospholipids (especially phosphatidylcholine). A low content of polyunsatured fatty acids and a high amount of monounsaturated fatty acids are found in phospholipids of these abnormal lipoproteins and of the hepatic bile. The ratio polyunsaturated/monounsaturated fatty acids is very different in phospholipids of normal serum lipoproteins, it characterizes the abnormal lipoproteins.

Les lipides liés de l’aorte humaine athéroscléreuse

Summary Previous studies on the lipid content of human aortic wall have indicated that the tissue contains small amounts of that are not extractable by lipid solvents unless the structure of the wall is destroyed; the presence of these lipids, apparently nearly phospholipids rich in dienoic fatty acids has been inferred from histochemical methods. In the present study, these lipids were extracted from intima and media of atheromatous human aortas after treatment with pepsin and trypsin, and separated by thin-layer chromatography. They were particularly rich in glycerides and free fatty acids (compared to aortic extracted normally). There was no significant difference in content between intima and media, except that media contained a higher proportion of phospholipids. The fatty acids of the various lipid classes contained high proportions of stearic acid and, in the free fatty acids and media phospholipids, of unidentified fatty acids that may be unsaturated C 12 acids. One polar fraction (soluble in chloroform but not in hexane) does not migrate in thin-layer chromatography, even in highly polar solvents. It contains non-lipid components fluorescent in ultraviolet light and also components rich in phosphorus, perhaps phospholipids. A possible atherogenic role is suggested for these bound lipids.

Purification of vesicular stomatitis virus and the analysis of P 32-labeled viral components

Vesicular stomatitis virus, grown in vitro in Earle's L cells, was purified using a caesium chloride equilibrium gradient. The infectious virus particles were found in a narrow zone about a density of 1.20 g/ml. The use of isotopically labelled virus, first partially purified by differential centrifugation, showed that a second, less dense, but noninfectious band of radioactive material was also present. A chemical analysis of the purified infectious material showed that VSV is an RNA virus containing a high proportion of phospholipid. These results were confirmed by IUDR and chloroform sensitivity studies. The material in the less dense, noninfectious band had a chemical constitution similar to that of the infectious particles.

The glycerol-phospho-protein complex envelope of Micrococcus pyogenes.

SUMMARY: The glycerophospho-compound which has been shown to account for more than one-quarter of the total organic phosphate of Micrococcus pyogenes is present almost exclusively in the particulate fractions of mechanically disintegrated cell suspensions. The main particulate fraction corresponds to the cell envelope material of Dawson (1949). Three-quarters of the weight of this material is made up of a glycerophospho-protein complex of which the protein moiety resembles silk fibrom in amino-acid composition and in its general properties. The amount of hydroxylamino-acid in the protein of the envelope would be sufficient to bind the polyolphosphoric acids covalently, but the possibility that the polyolphosphoric acids form a polymer which is adsorbed on to a protein matrix is not excluded. A subsidiary particulate fraction, made up of very small particles containing a high proportion of phospholipid, was found to be otherwise similar in composition to the envelope fraction. It is suggested that in the intact cell, the material of the small particle fraction may form a continuous layer (lipid membrane?) lying beneath the glycerophospho-protein complex envelope (cell wall?).