The Effect of Acetylsalicylic Acid, as a Representative Non-Steroidal Anti-Inflammatory Drug, on the Activity of Myeloperoxidase

Figures

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  Figure 1. (a) UV-Vis spectrum for 100 μM acetylsalicylic acid and (b) the spectra recorded during the oxidation of 100 μM ASA by 5 μg/mL (0.25 U/mL) myeloperoxidase in the presence of 100 μM H2O2 in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C. The spectra were recorded every 1 min for 10 min.

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  Figure 2. (a) Time spectra recorded for the oxidation of 130 μM o-dianisidine by 5 μg/mL (0.25 U/mL) myeloperoxidase in the presence of 60 μM H2O2 in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C; (b) spectra after 10 min for the enzymatic oxidation of 130 μM o-dianisidine in the presence of 60 μM H2O2 without ASA and in the presence of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C. The concentration of myeloperoxidase was 5 μg/mL (0.25 U/mL) in all reactions.

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  Figure 3. (a) Reaction progress curves at 460 nm wavelength for the enzymatic oxidation of 130 μM o-dianisidine in the presence of 60 μM H2O2 without ASA and in the presence of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C; (b) the % inhibition of individual concentrations of ASA after the enzymatic oxidation of 130 μM o-dianisidine in the presence of 60 μM H2O2 and after the addition of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C. The concentration of myeloperoxidase was 5 μg/mL (0.25 U/mL) in all reactions.

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  Figure 4. (a) Reaction progress curves at 290 nm for the enzymatic oxidation of 50 μM monochlorodimedone in the presence of 100 mM NaCl and 50 μM H2O2 without ASA and in the presence of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM acetate buffer, pH 5.0 at 25 °C; (b) the % inhibition for individual concentrations of ASA after enzymatic oxidation of 50 μM monochlorodimedone in the presence of 100 mM NaCl and 50 μM H2O2 and after the addition of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM acetate buffer, pH 5, 0 at 25 °C. The myeloperoxidase concentration was 5 μg/mL (0.25 U/mL) in all reactions.

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  Figure 5. (a) Time spectra recorded for the reaction of 50 μM 4-aminoantipyrine, 1 mM phenol, 100 μM H2O2, and 2.5 μg/mL (0.125 U/mL) myeloperoxidase in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C; (b) spectra after 10 min for the enzymatic oxidation reaction of 50 μM 4-aminoantipyrine and 1 mM phenol with 100 μM H2O2 without ASA and in the presence of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C.

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  Figure 6. (a) Reaction progress curves at 505 nm for the enzymatic oxidation of 50 μM 4-aminoantipyrine, 1 mM phenol, 100 μM H2O2 without ASA and in the presence of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C; (b) the % inhibition for individual concentrations of ASA after enzymatic oxidation of 50 μM 4-aminoantipyrine, 1 mM phenol, 100 μM H2O2 and after the addition of 10 mM, 20 mM, 30 mM, 40 mM and 50 mM ASA in 50 mM sodium phosphate buffer, pH 7.4 at 25 °C. The myeloperoxidase concentration was 2.5 μg/mL (0.125 U/mL) in all reactions.