Novel adducts from the modification of nucleic acid bases by malondialdehyde

Nair, Vasu; Turner, Gregory A.; Offerman, Rick J.

doi:10.1021/ja00323a061

Cited by 89 publications

(64 citation statements)

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“…13,14 To minimize free radical damage, there is a complex antioxidant defense system, which includes the interaction of free radicals with antioxidants to form less reactive compounds. Cells maintain their vital functions against oxidative damage with the help of a system that involves GSH-Px, SOD, catalase, glutathione reductase, some trace elements and vitamins A, E and C. 15 Recent studies have revealed that superoxide formation is enhanced and SOD is inhibited by nonenzymic glycation in metabolic disorders associated with obesity. Moreover hyperlipidemia is known to increase endothelial superoxide production.…”

Section: Introductionmentioning

confidence: 99%

Oxidative status and serum leptin levels in obese prepubertal children

Üstündağ

Güngör

Aygün

et al. 2006

Cell Biochemistry & Function

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The prevalence of obesity in children has increased dramatically over the last 20-30 years in developed countries. The aim of this study was to evaluate the oxidative and antioxidant status and any correlation with leptin in obese prepubertal children. A cross-sectional study was made of healthy children from ten elementary schools in the province of Elazig, Eastern Turkey. Blood samples were drawn from children comprising obese and control groups, on a visit to their school in the morning after an overnight fast. The mean body mass index (BMI) was 24.03 +/- 4.09 kg/m(2) in the obese group and was 17.51 +/- 2.33 kg/m(2) in the control group. Mean plasma leptin concentration was significantly higher in the obese children. Homocysteine and malondialdehyde (MDA) levels were also significantly higher in the obese group. In contrast superoxide dismutase (SOD) and glutathione peroxidase activities were significantly decreased in the obese group (p < 0.001). In conclusion, in prepubertal obese children oxidative stress was increased and MDA and homocysteine levels were well correlated with serum leptin level and BMI. In contrast with the increase in oxidative stress, antioxidant activities of SOD and glutathione peroxidase were decreased in obese prepubertal children.

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Section: Introductionmentioning

confidence: 99%

Oxidative status and serum leptin levels in obese prepubertal children

Üstündağ

Güngör

Aygün

et al. 2006

Cell Biochemistry & Function

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“…1,7 This chemical behavior is a concern because both acidic and basic conditions are encountered during the dodecamer synthesis based on the solid-phase method by 2-cyanoethylphosphoramidite chemistry. 8,9 Several works have described improved conditions for oligonucleotide synthesis. 10 Some of them substitute the more common 5Ј-hydroxyl protector group employed in the dodecamer synthesis, 4,4Ј-dimethoxytrityl (DMT), with a more acid labile group such as 9-phenylxanthene or pixyl group, 11 and/or modify the basic treatment for the cleavage of the dodecamers from the supports.…”

Section: Introductionmentioning

confidence: 99%

“…Finally, the first species is the initial K nucleoside. 1,9 Kinetics of the dodecamer sample was also studied at pH 3.1 for 24 h. During this time, no spectral changes were observed that could be related to the hydrolytic deavage of the glycosyl bond in the dodecamer. From the comparison of these results with those obtained for the K nucleoside in the same experimental conditions, it was concluded that the stability of the K nucleoside increased dramatically upon incorporation into the dodecamer.…”

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confidence: 99%

Synthesis, stability, and protonation studies of a self‐complementary dodecamer containing the modified nucleoside 2′‐deoxyzebularine

et al. 2003

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The nucleoside 2'-deoxyzebularine (K) was incorporated into the self-complementary dodecamer 5'-CGTACGKGTACG-3' by solid-phase 2-cyanoethylphosphoramidite chemistry using dimethoxytrityl (DMT) as the 5'-hydroxyl protecting group. Standard synthesis cycles using trichloroacetic acid and short ammonia treatment (50 degrees C for 30 min) were found to be the optimal conditions to obtain the desired dodecamer with minimum acid and basic degradation of the acid- and base-sensitive 2-pyrimidinone residue. The protonation equilibria of the K nucleoside and of the dodecamer at 37 degrees C were studied by means of spectroscopically monitored titrations. For the K nucleoside, a pK(a) value of 3.13 +/- 0.09 was obtained. For the dodecamer, four acid-base species were found in the pH range 2-12, with pK(a) values of 9.60 +/- 0.07, 4.46 +/- 0.16, and 2.87 +/- 0.19. Melting experiments were carried out to confirm the proposed acid-base concentration profiles. Finally, kinetic experiments were also carried out at several pH values to evaluate the stability of the K nucleoside and of the dodecamer. An increased stability was shown by the K nucleoside when incorporated into the dodecamer. Multivariate methods based on both hard- and soft-modeling were applied for the analysis of spectroscopic data, allowing the estimation of concentration profiles and pure spectra.

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“…It has been reported that MDA appears to be involved in the formation of age pigments [10], as well as undergo ing reactions with important biological compounds such as amino acids, proteins and nucleic acids [11,12]. MDA has also been extensively used as a marker of lipid peroxi dation mainly in processes associated with oxidative stress and vascular injury.…”

Section: Introductionmentioning

confidence: 99%

Impairment of Acetylcholine Relaxations by Malondialdehyde, a Marker of Lipid Peroxidation

Rodríguez-Martínez

Martı́nez-Orgado²,

Salaíces³

et al. 1996

J Vasc Res

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The effect of malondialdehyde (MDA), a lipid peroxidation marker, on the relaxations evoked by acetylcholine (ACh) was analyzed in tail arteries of Sprague-Dawley rats, which have MDA plasma levels of 0.43 ± 0.10 µM. MDA (0.5–30 µM) produced an inhibition of ACh relaxations that persisted after repeated washing periods, and was independent of the incubation time. MDA did not modify the vasodilator responses to either exogenous nitric oxide (NO) or sodium nitroprusside, a NO donor. L-Arginine (the NO synthase substrate) did not prevent the impairment of relaxations to ACh caused by MDA. The association of N^ω-nitro-L-arginine methyl ester (a NO synthase inhibitor) and MDA produced an additive inhibition of the Ach induced relaxations. Superoxide dismutase (a superoxide anion scavenger) completely reversed the inhibitory effect of MDA. These results suggest: (1) MDA is not only a marker of lipid peroxidation but also an agent that can impair endothelium-dependent relaxations; (2) this impairment does not seem to be due to an interference with guanylate cyclase activation by NO or with NO synthase pathway; (3) the effect of MDA appears to be mediated by superoxide anion, and (4) MDA could propagate lipid peroxidation chain reactions in endothelial membranes, that could alter the function of muscarinic receptors.

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Novel adducts from the modification of nucleic acid bases by malondialdehyde

Cited by 89 publications

References 0 publications

Oxidative status and serum leptin levels in obese prepubertal children

Oxidative status and serum leptin levels in obese prepubertal children

Synthesis, stability, and protonation studies of a self‐complementary dodecamer containing the modified nucleoside 2′‐deoxyzebularine

Impairment of Acetylcholine Relaxations by Malondialdehyde, a Marker of Lipid Peroxidation

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