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Free-radical Destruction of Sphingolipids Resulting in 2-hexadecenal Formation.

Shadyro O, Lisovskaya A, Semenkova G, Edimecheva I, Amaegberi N - Lipid Insights (2015)

Bottom Line: These findings prove the existence of a nonenzymatic pathway of sphingolipid destruction leading to the formation of Hex, which possesses a wide spectrum of biological activity.Analysis of the effect of HOCl on transplantable rat glioma C6 cells and human embryonic kidney 293 cells points to the formation of Hex.This suggests that the described mechanism of free-radical destruction of sphingolipids may be replicated on cell culture under the stress of active chlorine forms.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Belarusian State University, Minsk, Belarus.

ABSTRACT
The action of hypochlorous acid (HOCl) and γ-radiation on aqueous lysosphingolipid dispersions was found to produce 2-hexadecenal (Hex). This process includes the stages of formation of nitrogen-centered radicals from the starting molecules and the subsequent fragmentation of these radicals via the rupture of C-C and O-H bonds. These findings prove the existence of a nonenzymatic pathway of sphingolipid destruction leading to the formation of Hex, which possesses a wide spectrum of biological activity. Analysis of the effect of HOCl on transplantable rat glioma C6 cells and human embryonic kidney 293 cells points to the formation of Hex. This suggests that the described mechanism of free-radical destruction of sphingolipids may be replicated on cell culture under the stress of active chlorine forms.

No MeSH data available.


Related in: MedlinePlus

Formation of Hex in aqueous dispersions of SPH (A) and SPC (B) under the action of MPO/H2O2/Cl− system. 1—sphingolipid dispersion; 2—sphingolipid dispersion/0.3 mM H2O2; 3—sphingolipid dispersion/MPO; 4—sphingolipid dispersion/MPO/0.3 mM H2O2; 5—sphingolipid dispersion/MPO/0.6 mM H2O2; 6—sphingolipid dispersion/MPO/1.0 mM H2O2; 7—sphingolipid dispersion/MPO/1.2 mM H2O2. The reactions were conducted in 50 mM PBS, 140 mM NaCl, pH 4, T = 37°C, t = 60 minutes. The sphingolipid concentration in the system thus obtained was 5 mM, and that of MPO was 1.5 U/mL. Error bars indicate SD of the means (n ≥ 3).
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f4-lpi-8-2015-001: Formation of Hex in aqueous dispersions of SPH (A) and SPC (B) under the action of MPO/H2O2/Cl− system. 1—sphingolipid dispersion; 2—sphingolipid dispersion/0.3 mM H2O2; 3—sphingolipid dispersion/MPO; 4—sphingolipid dispersion/MPO/0.3 mM H2O2; 5—sphingolipid dispersion/MPO/0.6 mM H2O2; 6—sphingolipid dispersion/MPO/1.0 mM H2O2; 7—sphingolipid dispersion/MPO/1.2 mM H2O2. The reactions were conducted in 50 mM PBS, 140 mM NaCl, pH 4, T = 37°C, t = 60 minutes. The sphingolipid concentration in the system thus obtained was 5 mM, and that of MPO was 1.5 U/mL. Error bars indicate SD of the means (n ≥ 3).

Mentions: It has been found in this study that the respective chlorinated derivatives and Hex can also be formed from lysosphingolipids under the action of reactive chlorine species generated in the MPO-mediated halogenating cycle. Aqueous dispersions of SPH and SPC prepared as indicated in “Methods” were incubated for 60 minutes at 37°C with the hypochlorous acid formed from the MPO-catalyzed reaction in the presence of H2O2 at various concentrations (0.3–1.2 mM). The reaction was carried out at pH values ranging from 4 to 7.4. The sphingolipid dispersions were found to yield maximum amounts of Hex when the pH of the medium was ≤4.5, in accordance with the literature data showing that MPO acts mainly in the halogenating mode at acidic pH values, yielding maximum amounts of HOCl.26 The diagrams in Figure 4 show the concentrations of Hex formed in aqueous dispersions of SPH (A) and SPC (B) in reaction mixtures of various compositions.


Free-radical Destruction of Sphingolipids Resulting in 2-hexadecenal Formation.

Shadyro O, Lisovskaya A, Semenkova G, Edimecheva I, Amaegberi N - Lipid Insights (2015)

Formation of Hex in aqueous dispersions of SPH (A) and SPC (B) under the action of MPO/H2O2/Cl− system. 1—sphingolipid dispersion; 2—sphingolipid dispersion/0.3 mM H2O2; 3—sphingolipid dispersion/MPO; 4—sphingolipid dispersion/MPO/0.3 mM H2O2; 5—sphingolipid dispersion/MPO/0.6 mM H2O2; 6—sphingolipid dispersion/MPO/1.0 mM H2O2; 7—sphingolipid dispersion/MPO/1.2 mM H2O2. The reactions were conducted in 50 mM PBS, 140 mM NaCl, pH 4, T = 37°C, t = 60 minutes. The sphingolipid concentration in the system thus obtained was 5 mM, and that of MPO was 1.5 U/mL. Error bars indicate SD of the means (n ≥ 3).
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4376205&req=5

f4-lpi-8-2015-001: Formation of Hex in aqueous dispersions of SPH (A) and SPC (B) under the action of MPO/H2O2/Cl− system. 1—sphingolipid dispersion; 2—sphingolipid dispersion/0.3 mM H2O2; 3—sphingolipid dispersion/MPO; 4—sphingolipid dispersion/MPO/0.3 mM H2O2; 5—sphingolipid dispersion/MPO/0.6 mM H2O2; 6—sphingolipid dispersion/MPO/1.0 mM H2O2; 7—sphingolipid dispersion/MPO/1.2 mM H2O2. The reactions were conducted in 50 mM PBS, 140 mM NaCl, pH 4, T = 37°C, t = 60 minutes. The sphingolipid concentration in the system thus obtained was 5 mM, and that of MPO was 1.5 U/mL. Error bars indicate SD of the means (n ≥ 3).
Mentions: It has been found in this study that the respective chlorinated derivatives and Hex can also be formed from lysosphingolipids under the action of reactive chlorine species generated in the MPO-mediated halogenating cycle. Aqueous dispersions of SPH and SPC prepared as indicated in “Methods” were incubated for 60 minutes at 37°C with the hypochlorous acid formed from the MPO-catalyzed reaction in the presence of H2O2 at various concentrations (0.3–1.2 mM). The reaction was carried out at pH values ranging from 4 to 7.4. The sphingolipid dispersions were found to yield maximum amounts of Hex when the pH of the medium was ≤4.5, in accordance with the literature data showing that MPO acts mainly in the halogenating mode at acidic pH values, yielding maximum amounts of HOCl.26 The diagrams in Figure 4 show the concentrations of Hex formed in aqueous dispersions of SPH (A) and SPC (B) in reaction mixtures of various compositions.

Bottom Line: These findings prove the existence of a nonenzymatic pathway of sphingolipid destruction leading to the formation of Hex, which possesses a wide spectrum of biological activity.Analysis of the effect of HOCl on transplantable rat glioma C6 cells and human embryonic kidney 293 cells points to the formation of Hex.This suggests that the described mechanism of free-radical destruction of sphingolipids may be replicated on cell culture under the stress of active chlorine forms.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Belarusian State University, Minsk, Belarus.

ABSTRACT
The action of hypochlorous acid (HOCl) and γ-radiation on aqueous lysosphingolipid dispersions was found to produce 2-hexadecenal (Hex). This process includes the stages of formation of nitrogen-centered radicals from the starting molecules and the subsequent fragmentation of these radicals via the rupture of C-C and O-H bonds. These findings prove the existence of a nonenzymatic pathway of sphingolipid destruction leading to the formation of Hex, which possesses a wide spectrum of biological activity. Analysis of the effect of HOCl on transplantable rat glioma C6 cells and human embryonic kidney 293 cells points to the formation of Hex. This suggests that the described mechanism of free-radical destruction of sphingolipids may be replicated on cell culture under the stress of active chlorine forms.

No MeSH data available.


Related in: MedlinePlus