Display Settings:

Items per page
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information

Results: 13

1.
Figure 1

Figure 1. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Aldehydes known to form al-PEs. Well-established aldehydes from lipid peroxidation including 4-hydroxynonenal (HNE), 4-oxononenal (ONE), acrolein, malondialdehyde (MDA), isolevuglandin (IsoLG), p-hydroxyphenylacetaldehyde (pHA), and glucose have been shown to modify animo headgroup of PE to form various types of al-PEs.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
2.
Figure 8

Figure 8. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Potential unifying mechanism of formation of C6:0NAPE, C4:0CAPE, C7:1 CAPE and C9:2CAPE. Formation of C6:0NAPE via 15-HPETE suggests C4:0CAPE and C7:1 CAPE as products from 5-HPETE and 8-HPETE, respectively. They are consistent with PE+114 and PE+154 detected in oxidized liposomes. Formation of a minor product, 11-HPETE, would give rise to C9:2 CAPE which is consistent with PE+180.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
3.
Figure 4

Figure 4. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Mass spectrum of each novel chromatographic peak identified from oxidized arachidonic acid and diPPE. The most abundant al-PE species were selected for analysis (labeled by m/z). The m/z1039 ion was identified as the hydroxylactam species of IsoLG-PE based on its mass and retention time identified in earlier studies.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
4.
Figure 7

Figure 7. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Putative structures of novel al-PEs generated in lipid peroxidation. These structures were based on chemical formulas identified by MS and previously described reaction pathways for lipid peroxidation. For C7:1CAPE and C9:2CAPE, the structures shown represent only one of a number of possible regioisomers in terms of the position and stereochemistry of double bonds that would be consistent with the data.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
5.
Figure 12

Figure 12. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Al-PEs generated in oxidized HDL. Isolated human HDL was oxidized by (A) tBHP and (B) MPO and then analyzed by MS with base hydrolysis. The oxidized HDL generated same al-PE species, which were hydrolyzed by NaOH to remove the two O-acyl chains. The resulting al-GPs were monitored by MS operated in the MRM mode, using individual negative precursor ion mass and m/z79 (phosphate) product ion.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
6.
Figure 2

Figure 2. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

PE modification is a major target of endogenously formed IsoLG in oxidized HDL. Human HDL was oxidized by myeloperoxidase (MPO). The modified protein and PE were separated by folch extraction. The organic layer containing modified PE and the protein layer were analyzed by MS. Significantly greater levels of IsoLG-PE than IsoLG-modified protein were detected (two-tailed t test, p = 0.0015).

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
7.
Figure 13

Figure 13. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Induction of THP-1 monocyte adhesion to HUVEC by individual al-PE species. HUVEC were treated with varying concentrations of each al-PE (0–25 μM), and activation of HUVEC was measured by adhesion of calcein-labeled THP-1 using LPS (10 μg/mL) as positive control. (A) DHP-PE (one-way ANOVA, p < 0.0001); (B) HNE-PE (one-way ANOVA, ns); (C) ONE-PE (one-way ANOVA, p = 0.0027); (D) C11:0CAPE (one-way ANOVA, p < 0.0001); (E) pHA-PE (one-way ANOVA, p < 0.0001); (F) acrolein-PE (one-way ANOVA, ns); (G) amadori-PE (one-way ANOVA, ns); (H) C2:0NAPE (one-way ANOVA, p = 0.03); (I) C6:0NAPE (one-way ANOVA, ns); and (J) C4:0CAPE (one-way ANOVA, ns).

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
8.
Figure 6

Figure 6. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Relative abundance of Al-PEs is oxidized SAPC/diPPE liposomes. Liposomes were oxidized by copper(II) (Cu-ox) or t-butylhydroperoxide (tBHP) and formation of al-PEs were monitored by MS precursor scanning of m/z 255 product ions. Oxidation of esterified arachidonic acid resulted in formation of same al-PE products as detected in the reaction with free arachidonic acid, although relative abundance differed. The ion peaks including PE+348, PE+114, PE+154, and PE+180 showed relatively lower abundance when esterified arachidonic acid was used, suggesting that these al-PEs may be esterified products.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
9.
Figure 9

Figure 9. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

LC/MS/MS analysis of (A) synthetic al-PEs or (B) al-PEs generated by oxidation of SAPC-diPPE liposomes. The mass spectrometer was operated in the multiple reaction monitoring (MRM) mode, mass transitions with the product ion of m/z 255.1 for the specific parent ion at collision energy of 50 eV were monitored. The chromatographic results were processed in Xcaliber software (ThermoFinnigan) using 9-point Gaussian smoothing.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
10.
Figure 5

Figure 5. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Relative abundance of al-PEs in copper oxidized versus unoxidized arachidonic acid and diPPE. The relative abundance was calculated as the ratio of individual al-PE peak height to internal standard peak height. The most abundant al-PEs in MS analysis represented mass shifts of 28, 42, 54, 72, 98, 114, 154, 172, 180, 348 and 364 amu from the starting diPPE.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
11.
Figure 11

Figure 11. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Relative abundance of corresponding aldehyde-modified ethanolamine glycerophosphates (al-GPs) after base hydrolysis of al-PE generated by tBHP oxidation of SAPC/diPPE liposomes. Al-PEs from oxidized liposomes were hydrolyzed by sodium hydroxide in methanol. The resulting al-GPs were purified by C18 solid phase extraction cartridge and monitored by MS operating in the MRM mode using m/z79 product ion (phosphate) for individual MRM transitions.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
12.
Figure 3

Figure 3. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Formation of al-PEs by oxidation of arachidonic acid (AA) in the presence of dipalmitoyl PE (diPPE). AA was oxidized by copper(II)/hydrogen peroxide in the presence of diPPE and the resulting modified PEs were characterized by LC/MS/MS. (A) Schematic of reaction and analysis. LC/MS/MS precursor scanning with the product ion set at m/z 255.1 selects for the O-palmitoyl fragment of N-modified PE species. (B) Six novel chromatographic peaks were detected in the reaction of oxidized AA with PE that were not present in the non-oxidized control. C17:0NAPE used as internal standard and eluted at 5.35 min.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.
13.
Figure 10

Figure 10. From: Identification of Novel Bioactive Aldehyde-modified Phosphatidylethanolamines Formed by Lipid Peroxidation.

Derivatization of al-PE with pentafluorobenzyl bromide (PFBB) confirms presence of carboxylate moiety for specific al-PEs. (A) Effect of reaction with PFBB on LC/MS/MS signal intensity for individual al-PEs generated by oxidized arachidonic acid in the presence of diPPE. (B) Reaction of this oxidized lipid mixture with PFBB (right column) generates ions consistent with PFB esters that are not present in the absence of PFBB treatment (left column). The mass spectrometer was operated in the MRM mode using transitions from the appropriate parent ion to m/z 255.1 with collision energy of 50 eV. For MRM of PFB esters, appropriate parent ions were chosen by adding 180 amu to the mass of each alPE whose putative structure includes a carboxylate moiety.

Lilu Guo, et al. Free Radic Biol Med. 2012 September 15;53(6):1226-1238.

Display Settings:

Items per page

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Write to the Help Desk