Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite

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Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite. / Thomas, S R; Davies, Michael Jonathan; Stocker, R.

In: Chemical Research in Toxicology, Vol. 11, No. 5, 1998, p. 484-94.

Research output: Contribution to journalJournal articlepeer-review

Harvard

Thomas, SR, Davies, MJ & Stocker, R 1998, 'Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite', Chemical Research in Toxicology, vol. 11, no. 5, pp. 484-94. https://doi.org/10.1021/tx970173a

APA

Thomas, S. R., Davies, M. J., & Stocker, R. (1998). Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite. Chemical Research in Toxicology, 11(5), 484-94. https://doi.org/10.1021/tx970173a

Vancouver

Thomas SR, Davies MJ, Stocker R. Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite. Chemical Research in Toxicology. 1998;11(5):484-94. https://doi.org/10.1021/tx970173a

Author

Thomas, S R ; Davies, Michael Jonathan ; Stocker, R. / Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite. In: Chemical Research in Toxicology. 1998 ; Vol. 11, No. 5. pp. 484-94.

Bibtex

@article{0f215f88530b4d179af51997ce89abb3,
title = "Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite",
abstract = "As peroxynitrite is implicated as an oxidant for low-density lipoprotein (LDL) in atherogenesis, we investigated this process using reagent peroxynitrite (ONOO-) and 3-morpholinosydnonimine (SIN-1, which produces peroxynitrite via generation of NO. and O2.-). LDL oxidation was assessed by the consumption of ubiquinol-10 (CoQ10H2) and alpha-tocopherol (alpha-TOH), the accumulation of cholesteryl ester hydro(pero)xides, the loss of lysine (Lys) and tryptophan (Trp) residues, and the change in relative electrophoretic mobility. Exposure to ONOO- or SIN-1 resulted in rapid (<1 min) and time-dependent oxidation, respectively, of LDL's lipids and protein. Manipulating the alpha-TOH content by in vivo or in vitro means showed that when ONOO- or SIN-1 was used at oxidant-to-LDL ratios of <100:1 the extent of LDL lipid peroxidation increased with increasing initial alpha-TOH content. In contrast, in vivo enrichment with the co-antioxidant CoQ10H2 decreased LDL lipid peroxidation induced by SIN-1. At oxidant-to-LDL ratios of >200:1, alpha-TOH enrichment decreased LDL lipid peroxidation for both SIN-1 and ONOO-. In contrast to lipid peroxidation, altering the alpha-TOH content of LDL did not affect Trp or Lys loss, independent of the amounts of either oxidant added. Aqueous antioxidants inhibited ONOO--induced lipid and protein oxidation with the order of efficacy: 3-hydroxyanthranilate (3-HAA) > urate > ascorbate. With SIN-1, these antioxidants inhibited Trp consumption, while only the co-antioxidants ascorbate and 3-HAA prevented alpha-TOH consumption and lipid peroxidation. Exposure of human plasma to SIN-1 resulted in the loss of ascorbate followed by loss of CoQ10H2 and bilirubin. Lipid peroxidation was inhibited during this period, though proceeded as a radical-chain process after depletion of these antioxidants and in the presence of alpha-TOH and urate. Bicarbonate at physiological concentrations decreased ONOO--induced lipid and protein oxidation, whereas it enhanced SIN-1-induced lipid peroxidation, Trp consumption, and alpha-tocopheroxyl radical formation in LDL. These results indicate an important role for tocopherol-mediated peroxidation and co-antioxidation in peroxynitrite-induced lipoprotein lipid peroxidation, especially when peroxynitrite is formed time-dependently by SIN-1. The studies also highlight differences between ONOO-- and SIN-1-induced LDL oxidation with regards to the effects of bicarbonate, ascorbate, and urate.",
keywords = "Adenosine Triphosphatases, Adult, Antioxidants, Enzyme Inhibitors, Female, Humans, Lipoproteins, LDL, Male, Mass Spectrometry, Molsidomine, Nitrates, Oxidants, Oxidation-Reduction, Plasma, Ubiquinone, Vitamin E",
author = "Thomas, {S R} and Davies, {Michael Jonathan} and R Stocker",
year = "1998",
doi = "10.1021/tx970173a",
language = "English",
volume = "11",
pages = "484--94",
journal = "Chemical Research in Toxicology",
issn = "0893-228X",
publisher = "American Chemical Society",
number = "5",

}

RIS

TY - JOUR

T1 - Oxidation and antioxidation of human low-density lipoprotein and plasma exposed to 3-morpholinosydnonimine and reagent peroxynitrite

AU - Thomas, S R

AU - Davies, Michael Jonathan

AU - Stocker, R

PY - 1998

Y1 - 1998

N2 - As peroxynitrite is implicated as an oxidant for low-density lipoprotein (LDL) in atherogenesis, we investigated this process using reagent peroxynitrite (ONOO-) and 3-morpholinosydnonimine (SIN-1, which produces peroxynitrite via generation of NO. and O2.-). LDL oxidation was assessed by the consumption of ubiquinol-10 (CoQ10H2) and alpha-tocopherol (alpha-TOH), the accumulation of cholesteryl ester hydro(pero)xides, the loss of lysine (Lys) and tryptophan (Trp) residues, and the change in relative electrophoretic mobility. Exposure to ONOO- or SIN-1 resulted in rapid (<1 min) and time-dependent oxidation, respectively, of LDL's lipids and protein. Manipulating the alpha-TOH content by in vivo or in vitro means showed that when ONOO- or SIN-1 was used at oxidant-to-LDL ratios of <100:1 the extent of LDL lipid peroxidation increased with increasing initial alpha-TOH content. In contrast, in vivo enrichment with the co-antioxidant CoQ10H2 decreased LDL lipid peroxidation induced by SIN-1. At oxidant-to-LDL ratios of >200:1, alpha-TOH enrichment decreased LDL lipid peroxidation for both SIN-1 and ONOO-. In contrast to lipid peroxidation, altering the alpha-TOH content of LDL did not affect Trp or Lys loss, independent of the amounts of either oxidant added. Aqueous antioxidants inhibited ONOO--induced lipid and protein oxidation with the order of efficacy: 3-hydroxyanthranilate (3-HAA) > urate > ascorbate. With SIN-1, these antioxidants inhibited Trp consumption, while only the co-antioxidants ascorbate and 3-HAA prevented alpha-TOH consumption and lipid peroxidation. Exposure of human plasma to SIN-1 resulted in the loss of ascorbate followed by loss of CoQ10H2 and bilirubin. Lipid peroxidation was inhibited during this period, though proceeded as a radical-chain process after depletion of these antioxidants and in the presence of alpha-TOH and urate. Bicarbonate at physiological concentrations decreased ONOO--induced lipid and protein oxidation, whereas it enhanced SIN-1-induced lipid peroxidation, Trp consumption, and alpha-tocopheroxyl radical formation in LDL. These results indicate an important role for tocopherol-mediated peroxidation and co-antioxidation in peroxynitrite-induced lipoprotein lipid peroxidation, especially when peroxynitrite is formed time-dependently by SIN-1. The studies also highlight differences between ONOO-- and SIN-1-induced LDL oxidation with regards to the effects of bicarbonate, ascorbate, and urate.

AB - As peroxynitrite is implicated as an oxidant for low-density lipoprotein (LDL) in atherogenesis, we investigated this process using reagent peroxynitrite (ONOO-) and 3-morpholinosydnonimine (SIN-1, which produces peroxynitrite via generation of NO. and O2.-). LDL oxidation was assessed by the consumption of ubiquinol-10 (CoQ10H2) and alpha-tocopherol (alpha-TOH), the accumulation of cholesteryl ester hydro(pero)xides, the loss of lysine (Lys) and tryptophan (Trp) residues, and the change in relative electrophoretic mobility. Exposure to ONOO- or SIN-1 resulted in rapid (<1 min) and time-dependent oxidation, respectively, of LDL's lipids and protein. Manipulating the alpha-TOH content by in vivo or in vitro means showed that when ONOO- or SIN-1 was used at oxidant-to-LDL ratios of <100:1 the extent of LDL lipid peroxidation increased with increasing initial alpha-TOH content. In contrast, in vivo enrichment with the co-antioxidant CoQ10H2 decreased LDL lipid peroxidation induced by SIN-1. At oxidant-to-LDL ratios of >200:1, alpha-TOH enrichment decreased LDL lipid peroxidation for both SIN-1 and ONOO-. In contrast to lipid peroxidation, altering the alpha-TOH content of LDL did not affect Trp or Lys loss, independent of the amounts of either oxidant added. Aqueous antioxidants inhibited ONOO--induced lipid and protein oxidation with the order of efficacy: 3-hydroxyanthranilate (3-HAA) > urate > ascorbate. With SIN-1, these antioxidants inhibited Trp consumption, while only the co-antioxidants ascorbate and 3-HAA prevented alpha-TOH consumption and lipid peroxidation. Exposure of human plasma to SIN-1 resulted in the loss of ascorbate followed by loss of CoQ10H2 and bilirubin. Lipid peroxidation was inhibited during this period, though proceeded as a radical-chain process after depletion of these antioxidants and in the presence of alpha-TOH and urate. Bicarbonate at physiological concentrations decreased ONOO--induced lipid and protein oxidation, whereas it enhanced SIN-1-induced lipid peroxidation, Trp consumption, and alpha-tocopheroxyl radical formation in LDL. These results indicate an important role for tocopherol-mediated peroxidation and co-antioxidation in peroxynitrite-induced lipoprotein lipid peroxidation, especially when peroxynitrite is formed time-dependently by SIN-1. The studies also highlight differences between ONOO-- and SIN-1-induced LDL oxidation with regards to the effects of bicarbonate, ascorbate, and urate.

KW - Adenosine Triphosphatases

KW - Adult

KW - Antioxidants

KW - Enzyme Inhibitors

KW - Female

KW - Humans

KW - Lipoproteins, LDL

KW - Male

KW - Mass Spectrometry

KW - Molsidomine

KW - Nitrates

KW - Oxidants

KW - Oxidation-Reduction

KW - Plasma

KW - Ubiquinone

KW - Vitamin E

U2 - 10.1021/tx970173a

DO - 10.1021/tx970173a

M3 - Journal article

C2 - 9585479

VL - 11

SP - 484

EP - 494

JO - Chemical Research in Toxicology

JF - Chemical Research in Toxicology

SN - 0893-228X

IS - 5

ER -

ID: 138284064